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));
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 (is_std_init_list (to) && expr
1404 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1405 return build_list_conv (to, expr, flags);
1407 if (expr != NULL_TREE
1408 && (MAYBE_CLASS_TYPE_P (from)
1409 || MAYBE_CLASS_TYPE_P (to))
1410 && (flags & LOOKUP_NO_CONVERSION) == 0)
1412 struct z_candidate *cand;
1413 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING));
1415 if (CLASS_TYPE_P (to)
1416 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1417 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1418 return build_aggr_conv (to, expr, flags);
1420 cand = build_user_type_conversion_1 (to, expr, convflags);
1422 conv = cand->second_conv;
1424 /* We used to try to bind a reference to a temporary here, but that
1425 is now handled after the recursive call to this function at the end
1426 of reference_binding. */
1433 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1434 functions. ARGS will not be changed until a single candidate is
1437 static struct z_candidate *
1438 add_candidate (struct z_candidate **candidates,
1439 tree fn, tree first_arg, const VEC(tree,gc) *args,
1440 size_t num_convs, conversion **convs,
1441 tree access_path, tree conversion_path,
1444 struct z_candidate *cand = (struct z_candidate *)
1445 conversion_obstack_alloc (sizeof (struct z_candidate));
1448 cand->first_arg = first_arg;
1450 cand->convs = convs;
1451 cand->num_convs = num_convs;
1452 cand->access_path = access_path;
1453 cand->conversion_path = conversion_path;
1454 cand->viable = viable;
1455 cand->next = *candidates;
1461 /* Create an overload candidate for the function or method FN called
1462 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1463 FLAGS is passed on to implicit_conversion.
1465 This does not change ARGS.
1467 CTYPE, if non-NULL, is the type we want to pretend this function
1468 comes from for purposes of overload resolution. */
1470 static struct z_candidate *
1471 add_function_candidate (struct z_candidate **candidates,
1472 tree fn, tree ctype, tree first_arg,
1473 const VEC(tree,gc) *args, tree access_path,
1474 tree conversion_path, int flags)
1476 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1480 tree orig_first_arg = first_arg;
1484 /* At this point we should not see any functions which haven't been
1485 explicitly declared, except for friend functions which will have
1486 been found using argument dependent lookup. */
1487 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1489 /* The `this', `in_chrg' and VTT arguments to constructors are not
1490 considered in overload resolution. */
1491 if (DECL_CONSTRUCTOR_P (fn))
1493 parmlist = skip_artificial_parms_for (fn, parmlist);
1494 skip = num_artificial_parms_for (fn);
1495 if (skip > 0 && first_arg != NULL_TREE)
1498 first_arg = NULL_TREE;
1504 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1505 convs = alloc_conversions (len);
1507 /* 13.3.2 - Viable functions [over.match.viable]
1508 First, to be a viable function, a candidate function shall have enough
1509 parameters to agree in number with the arguments in the list.
1511 We need to check this first; otherwise, checking the ICSes might cause
1512 us to produce an ill-formed template instantiation. */
1514 parmnode = parmlist;
1515 for (i = 0; i < len; ++i)
1517 if (parmnode == NULL_TREE || parmnode == void_list_node)
1519 parmnode = TREE_CHAIN (parmnode);
1522 if (i < len && parmnode)
1525 /* Make sure there are default args for the rest of the parms. */
1526 else if (!sufficient_parms_p (parmnode))
1532 /* Second, for F to be a viable function, there shall exist for each
1533 argument an implicit conversion sequence that converts that argument
1534 to the corresponding parameter of F. */
1536 parmnode = parmlist;
1538 for (i = 0; i < len; ++i)
1544 if (parmnode == void_list_node)
1547 if (i == 0 && first_arg != NULL_TREE)
1550 arg = VEC_index (tree, args,
1551 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1552 argtype = lvalue_type (arg);
1554 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1555 && ! DECL_CONSTRUCTOR_P (fn));
1559 tree parmtype = TREE_VALUE (parmnode);
1562 /* The type of the implicit object parameter ('this') for
1563 overload resolution is not always the same as for the
1564 function itself; conversion functions are considered to
1565 be members of the class being converted, and functions
1566 introduced by a using-declaration are considered to be
1567 members of the class that uses them.
1569 Since build_over_call ignores the ICS for the `this'
1570 parameter, we can just change the parm type. */
1571 if (ctype && is_this)
1574 = build_qualified_type (ctype,
1575 TYPE_QUALS (TREE_TYPE (parmtype)));
1576 parmtype = build_pointer_type (parmtype);
1579 if (ctype && i == 0 && DECL_COPY_CONSTRUCTOR_P (fn))
1581 /* Hack: Direct-initialize copy parm (i.e. suppress
1582 LOOKUP_ONLYCONVERTING) to make explicit conversion ops
1583 work. See also reference_binding. */
1584 lflags |= LOOKUP_COPY_PARM;
1585 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1586 lflags |= LOOKUP_NO_CONVERSION;
1589 lflags |= LOOKUP_ONLYCONVERTING;
1591 t = implicit_conversion (parmtype, argtype, arg,
1592 /*c_cast_p=*/false, lflags);
1596 t = build_identity_conv (argtype, arg);
1597 t->ellipsis_p = true;
1614 parmnode = TREE_CHAIN (parmnode);
1618 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1619 access_path, conversion_path, viable);
1622 /* Create an overload candidate for the conversion function FN which will
1623 be invoked for expression OBJ, producing a pointer-to-function which
1624 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1625 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1626 passed on to implicit_conversion.
1628 Actually, we don't really care about FN; we care about the type it
1629 converts to. There may be multiple conversion functions that will
1630 convert to that type, and we rely on build_user_type_conversion_1 to
1631 choose the best one; so when we create our candidate, we record the type
1632 instead of the function. */
1634 static struct z_candidate *
1635 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1636 tree first_arg, const VEC(tree,gc) *arglist,
1637 tree access_path, tree conversion_path)
1639 tree totype = TREE_TYPE (TREE_TYPE (fn));
1640 int i, len, viable, flags;
1641 tree parmlist, parmnode;
1644 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1645 parmlist = TREE_TYPE (parmlist);
1646 parmlist = TYPE_ARG_TYPES (parmlist);
1648 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
1649 convs = alloc_conversions (len);
1650 parmnode = parmlist;
1652 flags = LOOKUP_IMPLICIT;
1654 /* Don't bother looking up the same type twice. */
1655 if (*candidates && (*candidates)->fn == totype)
1658 for (i = 0; i < len; ++i)
1665 else if (i == 1 && first_arg != NULL_TREE)
1668 arg = VEC_index (tree, arglist,
1669 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
1670 argtype = lvalue_type (arg);
1673 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1675 else if (parmnode == void_list_node)
1678 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1679 /*c_cast_p=*/false, flags);
1682 t = build_identity_conv (argtype, arg);
1683 t->ellipsis_p = true;
1697 parmnode = TREE_CHAIN (parmnode);
1703 if (!sufficient_parms_p (parmnode))
1706 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
1707 access_path, conversion_path, viable);
1711 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1712 tree type1, tree type2, tree *args, tree *argtypes,
1724 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1725 convs = alloc_conversions (num_convs);
1726 flags |= LOOKUP_ONLYCONVERTING;
1728 for (i = 0; i < 2; ++i)
1733 t = implicit_conversion (types[i], argtypes[i], args[i],
1734 /*c_cast_p=*/false, flags);
1738 /* We need something for printing the candidate. */
1739 t = build_identity_conv (types[i], NULL_TREE);
1746 /* For COND_EXPR we rearranged the arguments; undo that now. */
1749 convs[2] = convs[1];
1750 convs[1] = convs[0];
1751 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1752 /*c_cast_p=*/false, flags);
1759 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
1761 /*access_path=*/NULL_TREE,
1762 /*conversion_path=*/NULL_TREE,
1767 is_complete (tree t)
1769 return COMPLETE_TYPE_P (complete_type (t));
1772 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1775 promoted_arithmetic_type_p (tree type)
1779 In this section, the term promoted integral type is used to refer
1780 to those integral types which are preserved by integral promotion
1781 (including e.g. int and long but excluding e.g. char).
1782 Similarly, the term promoted arithmetic type refers to promoted
1783 integral types plus floating types. */
1784 return ((CP_INTEGRAL_TYPE_P (type)
1785 && same_type_p (type_promotes_to (type), type))
1786 || TREE_CODE (type) == REAL_TYPE);
1789 /* Create any builtin operator overload candidates for the operator in
1790 question given the converted operand types TYPE1 and TYPE2. The other
1791 args are passed through from add_builtin_candidates to
1792 build_builtin_candidate.
1794 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1795 If CODE is requires candidates operands of the same type of the kind
1796 of which TYPE1 and TYPE2 are, we add both candidates
1797 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1800 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1801 enum tree_code code2, tree fnname, tree type1,
1802 tree type2, tree *args, tree *argtypes, int flags)
1806 case POSTINCREMENT_EXPR:
1807 case POSTDECREMENT_EXPR:
1808 args[1] = integer_zero_node;
1809 type2 = integer_type_node;
1818 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1819 and VQ is either volatile or empty, there exist candidate operator
1820 functions of the form
1821 VQ T& operator++(VQ T&);
1822 T operator++(VQ T&, int);
1823 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1824 type other than bool, and VQ is either volatile or empty, there exist
1825 candidate operator functions of the form
1826 VQ T& operator--(VQ T&);
1827 T operator--(VQ T&, int);
1828 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1829 complete object type, and VQ is either volatile or empty, there exist
1830 candidate operator functions of the form
1831 T*VQ& operator++(T*VQ&);
1832 T*VQ& operator--(T*VQ&);
1833 T* operator++(T*VQ&, int);
1834 T* operator--(T*VQ&, int); */
1836 case POSTDECREMENT_EXPR:
1837 case PREDECREMENT_EXPR:
1838 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1840 case POSTINCREMENT_EXPR:
1841 case PREINCREMENT_EXPR:
1842 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1844 type1 = build_reference_type (type1);
1849 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1850 exist candidate operator functions of the form
1854 8 For every function type T, there exist candidate operator functions of
1856 T& operator*(T*); */
1859 if (TREE_CODE (type1) == POINTER_TYPE
1860 && (TYPE_PTROB_P (type1)
1861 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1865 /* 9 For every type T, there exist candidate operator functions of the form
1868 10For every promoted arithmetic type T, there exist candidate operator
1869 functions of the form
1873 case UNARY_PLUS_EXPR: /* unary + */
1874 if (TREE_CODE (type1) == POINTER_TYPE)
1877 if (ARITHMETIC_TYPE_P (type1))
1881 /* 11For every promoted integral type T, there exist candidate operator
1882 functions of the form
1886 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
1890 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1891 is the same type as C2 or is a derived class of C2, T is a complete
1892 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1893 there exist candidate operator functions of the form
1894 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1895 where CV12 is the union of CV1 and CV2. */
1898 if (TREE_CODE (type1) == POINTER_TYPE
1899 && TYPE_PTR_TO_MEMBER_P (type2))
1901 tree c1 = TREE_TYPE (type1);
1902 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1904 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
1905 && (TYPE_PTRMEMFUNC_P (type2)
1906 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1911 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1912 didate operator functions of the form
1917 bool operator<(L, R);
1918 bool operator>(L, R);
1919 bool operator<=(L, R);
1920 bool operator>=(L, R);
1921 bool operator==(L, R);
1922 bool operator!=(L, R);
1923 where LR is the result of the usual arithmetic conversions between
1926 14For every pair of types T and I, where T is a cv-qualified or cv-
1927 unqualified complete object type and I is a promoted integral type,
1928 there exist candidate operator functions of the form
1929 T* operator+(T*, I);
1930 T& operator[](T*, I);
1931 T* operator-(T*, I);
1932 T* operator+(I, T*);
1933 T& operator[](I, T*);
1935 15For every T, where T is a pointer to complete object type, there exist
1936 candidate operator functions of the form112)
1937 ptrdiff_t operator-(T, T);
1939 16For every pointer or enumeration type T, there exist candidate operator
1940 functions of the form
1941 bool operator<(T, T);
1942 bool operator>(T, T);
1943 bool operator<=(T, T);
1944 bool operator>=(T, T);
1945 bool operator==(T, T);
1946 bool operator!=(T, T);
1948 17For every pointer to member type T, there exist candidate operator
1949 functions of the form
1950 bool operator==(T, T);
1951 bool operator!=(T, T); */
1954 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1956 if (TYPE_PTROB_P (type1)
1957 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
1959 type2 = ptrdiff_type_node;
1963 case TRUNC_DIV_EXPR:
1964 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1970 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1971 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1973 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1978 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1990 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1992 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1994 if (TREE_CODE (type1) == ENUMERAL_TYPE
1995 && TREE_CODE (type2) == ENUMERAL_TYPE)
1997 if (TYPE_PTR_P (type1)
1998 && null_ptr_cst_p (args[1])
1999 && !uses_template_parms (type1))
2004 if (null_ptr_cst_p (args[0])
2005 && TYPE_PTR_P (type2)
2006 && !uses_template_parms (type2))
2014 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2017 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2019 type1 = ptrdiff_type_node;
2022 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2024 type2 = ptrdiff_type_node;
2029 /* 18For every pair of promoted integral types L and R, there exist candi-
2030 date operator functions of the form
2037 where LR is the result of the usual arithmetic conversions between
2040 case TRUNC_MOD_EXPR:
2046 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2050 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2051 type, VQ is either volatile or empty, and R is a promoted arithmetic
2052 type, there exist candidate operator functions of the form
2053 VQ L& operator=(VQ L&, R);
2054 VQ L& operator*=(VQ L&, R);
2055 VQ L& operator/=(VQ L&, R);
2056 VQ L& operator+=(VQ L&, R);
2057 VQ L& operator-=(VQ L&, R);
2059 20For every pair T, VQ), where T is any type and VQ is either volatile
2060 or empty, there exist candidate operator functions of the form
2061 T*VQ& operator=(T*VQ&, T*);
2063 21For every pair T, VQ), where T is a pointer to member type and VQ is
2064 either volatile or empty, there exist candidate operator functions of
2066 VQ T& operator=(VQ T&, T);
2068 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2069 unqualified complete object type, VQ is either volatile or empty, and
2070 I is a promoted integral type, there exist candidate operator func-
2072 T*VQ& operator+=(T*VQ&, I);
2073 T*VQ& operator-=(T*VQ&, I);
2075 23For every triple L, VQ, R), where L is an integral or enumeration
2076 type, VQ is either volatile or empty, and R is a promoted integral
2077 type, there exist candidate operator functions of the form
2079 VQ L& operator%=(VQ L&, R);
2080 VQ L& operator<<=(VQ L&, R);
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); */
2091 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2093 type2 = ptrdiff_type_node;
2097 case TRUNC_DIV_EXPR:
2098 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2102 case TRUNC_MOD_EXPR:
2108 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2113 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2115 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2116 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2117 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2118 || ((TYPE_PTRMEMFUNC_P (type1)
2119 || TREE_CODE (type1) == POINTER_TYPE)
2120 && null_ptr_cst_p (args[1])))
2130 type1 = build_reference_type (type1);
2136 For every pair of promoted arithmetic types L and R, there
2137 exist candidate operator functions of the form
2139 LR operator?(bool, L, R);
2141 where LR is the result of the usual arithmetic conversions
2142 between types L and R.
2144 For every type T, where T is a pointer or pointer-to-member
2145 type, there exist candidate operator functions of the form T
2146 operator?(bool, T, T); */
2148 if (promoted_arithmetic_type_p (type1)
2149 && promoted_arithmetic_type_p (type2))
2153 /* Otherwise, the types should be pointers. */
2154 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2155 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2158 /* We don't check that the two types are the same; the logic
2159 below will actually create two candidates; one in which both
2160 parameter types are TYPE1, and one in which both parameter
2168 /* If we're dealing with two pointer types or two enumeral types,
2169 we need candidates for both of them. */
2170 if (type2 && !same_type_p (type1, type2)
2171 && TREE_CODE (type1) == TREE_CODE (type2)
2172 && (TREE_CODE (type1) == REFERENCE_TYPE
2173 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2174 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2175 || TYPE_PTRMEMFUNC_P (type1)
2176 || MAYBE_CLASS_TYPE_P (type1)
2177 || TREE_CODE (type1) == ENUMERAL_TYPE))
2179 build_builtin_candidate
2180 (candidates, fnname, type1, type1, args, argtypes, flags);
2181 build_builtin_candidate
2182 (candidates, fnname, type2, type2, args, argtypes, flags);
2186 build_builtin_candidate
2187 (candidates, fnname, type1, type2, args, argtypes, flags);
2191 type_decays_to (tree type)
2193 if (TREE_CODE (type) == ARRAY_TYPE)
2194 return build_pointer_type (TREE_TYPE (type));
2195 if (TREE_CODE (type) == FUNCTION_TYPE)
2196 return build_pointer_type (type);
2200 /* There are three conditions of builtin candidates:
2202 1) bool-taking candidates. These are the same regardless of the input.
2203 2) pointer-pair taking candidates. These are generated for each type
2204 one of the input types converts to.
2205 3) arithmetic candidates. According to the standard, we should generate
2206 all of these, but I'm trying not to...
2208 Here we generate a superset of the possible candidates for this particular
2209 case. That is a subset of the full set the standard defines, plus some
2210 other cases which the standard disallows. add_builtin_candidate will
2211 filter out the invalid set. */
2214 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2215 enum tree_code code2, tree fnname, tree *args,
2220 tree type, argtypes[3];
2221 /* TYPES[i] is the set of possible builtin-operator parameter types
2222 we will consider for the Ith argument. These are represented as
2223 a TREE_LIST; the TREE_VALUE of each node is the potential
2227 for (i = 0; i < 3; ++i)
2230 argtypes[i] = unlowered_expr_type (args[i]);
2232 argtypes[i] = NULL_TREE;
2237 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2238 and VQ is either volatile or empty, there exist candidate operator
2239 functions of the form
2240 VQ T& operator++(VQ T&); */
2242 case POSTINCREMENT_EXPR:
2243 case PREINCREMENT_EXPR:
2244 case POSTDECREMENT_EXPR:
2245 case PREDECREMENT_EXPR:
2250 /* 24There also exist candidate operator functions of the form
2251 bool operator!(bool);
2252 bool operator&&(bool, bool);
2253 bool operator||(bool, bool); */
2255 case TRUTH_NOT_EXPR:
2256 build_builtin_candidate
2257 (candidates, fnname, boolean_type_node,
2258 NULL_TREE, args, argtypes, flags);
2261 case TRUTH_ORIF_EXPR:
2262 case TRUTH_ANDIF_EXPR:
2263 build_builtin_candidate
2264 (candidates, fnname, boolean_type_node,
2265 boolean_type_node, args, argtypes, flags);
2287 types[0] = types[1] = NULL_TREE;
2289 for (i = 0; i < 2; ++i)
2293 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2297 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2300 convs = lookup_conversions (argtypes[i]);
2302 if (code == COND_EXPR)
2304 if (real_lvalue_p (args[i]))
2305 types[i] = tree_cons
2306 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2308 types[i] = tree_cons
2309 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2315 for (; convs; convs = TREE_CHAIN (convs))
2317 type = TREE_TYPE (convs);
2320 && (TREE_CODE (type) != REFERENCE_TYPE
2321 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2324 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2325 types[i] = tree_cons (NULL_TREE, type, types[i]);
2327 type = non_reference (type);
2328 if (i != 0 || ! ref1)
2330 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2331 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2332 types[i] = tree_cons (NULL_TREE, type, types[i]);
2333 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2334 type = type_promotes_to (type);
2337 if (! value_member (type, types[i]))
2338 types[i] = tree_cons (NULL_TREE, type, types[i]);
2343 if (code == COND_EXPR && real_lvalue_p (args[i]))
2344 types[i] = tree_cons
2345 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2346 type = non_reference (argtypes[i]);
2347 if (i != 0 || ! ref1)
2349 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2350 if (enum_p && UNSCOPED_ENUM_P (type))
2351 types[i] = tree_cons (NULL_TREE, type, types[i]);
2352 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2353 type = type_promotes_to (type);
2355 types[i] = tree_cons (NULL_TREE, type, types[i]);
2359 /* Run through the possible parameter types of both arguments,
2360 creating candidates with those parameter types. */
2361 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2364 for (type = types[1]; type; type = TREE_CHAIN (type))
2365 add_builtin_candidate
2366 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2367 TREE_VALUE (type), args, argtypes, flags);
2369 add_builtin_candidate
2370 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2371 NULL_TREE, args, argtypes, flags);
2376 /* If TMPL can be successfully instantiated as indicated by
2377 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2379 TMPL is the template. EXPLICIT_TARGS are any explicit template
2380 arguments. ARGLIST is the arguments provided at the call-site.
2381 This does not change ARGLIST. The RETURN_TYPE is the desired type
2382 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2383 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2384 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2386 static struct z_candidate*
2387 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2388 tree ctype, tree explicit_targs, tree first_arg,
2389 const VEC(tree,gc) *arglist, tree return_type,
2390 tree access_path, tree conversion_path,
2391 int flags, tree obj, unification_kind_t strict)
2393 int ntparms = DECL_NTPARMS (tmpl);
2394 tree targs = make_tree_vec (ntparms);
2396 int skip_without_in_chrg;
2397 tree first_arg_without_in_chrg;
2398 tree *args_without_in_chrg;
2399 unsigned int nargs_without_in_chrg;
2400 unsigned int ia, ix;
2402 struct z_candidate *cand;
2406 nargs = (first_arg == NULL_TREE ? 0 : 1) + VEC_length (tree, arglist);
2408 skip_without_in_chrg = 0;
2410 first_arg_without_in_chrg = first_arg;
2412 /* We don't do deduction on the in-charge parameter, the VTT
2413 parameter or 'this'. */
2414 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2416 if (first_arg_without_in_chrg != NULL_TREE)
2417 first_arg_without_in_chrg = NULL_TREE;
2419 ++skip_without_in_chrg;
2422 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2423 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2424 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2426 if (first_arg_without_in_chrg != NULL_TREE)
2427 first_arg_without_in_chrg = NULL_TREE;
2429 ++skip_without_in_chrg;
2432 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2433 + (VEC_length (tree, arglist)
2434 - skip_without_in_chrg));
2435 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2437 if (first_arg_without_in_chrg != NULL_TREE)
2439 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2442 for (ix = skip_without_in_chrg;
2443 VEC_iterate (tree, arglist, ix, arg);
2446 args_without_in_chrg[ia] = arg;
2449 gcc_assert (ia == nargs_without_in_chrg);
2451 i = fn_type_unification (tmpl, explicit_targs, targs,
2452 args_without_in_chrg,
2453 nargs_without_in_chrg,
2454 return_type, strict, flags);
2459 fn = instantiate_template (tmpl, targs, tf_none);
2460 if (fn == error_mark_node)
2465 A member function template is never instantiated to perform the
2466 copy of a class object to an object of its class type.
2468 It's a little unclear what this means; the standard explicitly
2469 does allow a template to be used to copy a class. For example,
2474 template <class T> A(const T&);
2477 void g () { A a (f ()); }
2479 the member template will be used to make the copy. The section
2480 quoted above appears in the paragraph that forbids constructors
2481 whose only parameter is (a possibly cv-qualified variant of) the
2482 class type, and a logical interpretation is that the intent was
2483 to forbid the instantiation of member templates which would then
2485 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2487 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2488 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2493 if (obj != NULL_TREE)
2494 /* Aha, this is a conversion function. */
2495 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2496 access_path, conversion_path);
2498 cand = add_function_candidate (candidates, fn, ctype,
2499 first_arg, arglist, access_path,
2500 conversion_path, flags);
2501 if (DECL_TI_TEMPLATE (fn) != tmpl)
2502 /* This situation can occur if a member template of a template
2503 class is specialized. Then, instantiate_template might return
2504 an instantiation of the specialization, in which case the
2505 DECL_TI_TEMPLATE field will point at the original
2506 specialization. For example:
2508 template <class T> struct S { template <class U> void f(U);
2509 template <> void f(int) {}; };
2513 Here, TMPL will be template <class U> S<double>::f(U).
2514 And, instantiate template will give us the specialization
2515 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2516 for this will point at template <class T> template <> S<T>::f(int),
2517 so that we can find the definition. For the purposes of
2518 overload resolution, however, we want the original TMPL. */
2519 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2521 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2527 static struct z_candidate *
2528 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2529 tree explicit_targs, tree first_arg,
2530 const VEC(tree,gc) *arglist, tree return_type,
2531 tree access_path, tree conversion_path, int flags,
2532 unification_kind_t strict)
2535 add_template_candidate_real (candidates, tmpl, ctype,
2536 explicit_targs, first_arg, arglist,
2537 return_type, access_path, conversion_path,
2538 flags, NULL_TREE, strict);
2542 static struct z_candidate *
2543 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2544 tree obj, tree first_arg,
2545 const VEC(tree,gc) *arglist,
2546 tree return_type, tree access_path,
2547 tree conversion_path)
2550 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2551 first_arg, arglist, return_type, access_path,
2552 conversion_path, 0, obj, DEDUCE_CONV);
2555 /* The CANDS are the set of candidates that were considered for
2556 overload resolution. Return the set of viable candidates. If none
2557 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2558 is true if a candidate should be considered viable only if it is
2561 static struct z_candidate*
2562 splice_viable (struct z_candidate *cands,
2566 struct z_candidate *viable;
2567 struct z_candidate **last_viable;
2568 struct z_candidate **cand;
2571 last_viable = &viable;
2572 *any_viable_p = false;
2577 struct z_candidate *c = *cand;
2578 if (strict_p ? c->viable == 1 : c->viable)
2583 last_viable = &c->next;
2584 *any_viable_p = true;
2590 return viable ? viable : cands;
2594 any_strictly_viable (struct z_candidate *cands)
2596 for (; cands; cands = cands->next)
2597 if (cands->viable == 1)
2602 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2603 words, it is about to become the "this" pointer for a member
2604 function call. Take the address of the object. */
2607 build_this (tree obj)
2609 /* In a template, we are only concerned about the type of the
2610 expression, so we can take a shortcut. */
2611 if (processing_template_decl)
2612 return build_address (obj);
2614 return cp_build_unary_op (ADDR_EXPR, obj, 0, tf_warning_or_error);
2617 /* Returns true iff functions are equivalent. Equivalent functions are
2618 not '==' only if one is a function-local extern function or if
2619 both are extern "C". */
2622 equal_functions (tree fn1, tree fn2)
2624 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2625 || DECL_EXTERN_C_FUNCTION_P (fn1))
2626 return decls_match (fn1, fn2);
2630 /* Print information about one overload candidate CANDIDATE. MSGSTR
2631 is the text to print before the candidate itself.
2633 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2634 to have been run through gettext by the caller. This wart makes
2635 life simpler in print_z_candidates and for the translators. */
2638 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2640 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2642 if (candidate->num_convs == 3)
2643 inform (input_location, "%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2644 candidate->convs[0]->type,
2645 candidate->convs[1]->type,
2646 candidate->convs[2]->type);
2647 else if (candidate->num_convs == 2)
2648 inform (input_location, "%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2649 candidate->convs[0]->type,
2650 candidate->convs[1]->type);
2652 inform (input_location, "%s %D(%T) <built-in>", msgstr, candidate->fn,
2653 candidate->convs[0]->type);
2655 else if (TYPE_P (candidate->fn))
2656 inform (input_location, "%s %T <conversion>", msgstr, candidate->fn);
2657 else if (candidate->viable == -1)
2658 inform (input_location, "%s %+#D <near match>", msgstr, candidate->fn);
2660 inform (input_location, "%s %+#D", msgstr, candidate->fn);
2664 print_z_candidates (struct z_candidate *candidates)
2667 struct z_candidate *cand1;
2668 struct z_candidate **cand2;
2670 /* There may be duplicates in the set of candidates. We put off
2671 checking this condition as long as possible, since we have no way
2672 to eliminate duplicates from a set of functions in less than n^2
2673 time. Now we are about to emit an error message, so it is more
2674 permissible to go slowly. */
2675 for (cand1 = candidates; cand1; cand1 = cand1->next)
2677 tree fn = cand1->fn;
2678 /* Skip builtin candidates and conversion functions. */
2679 if (TREE_CODE (fn) != FUNCTION_DECL)
2681 cand2 = &cand1->next;
2684 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2685 && equal_functions (fn, (*cand2)->fn))
2686 *cand2 = (*cand2)->next;
2688 cand2 = &(*cand2)->next;
2695 str = _("candidates are:");
2696 print_z_candidate (str, candidates);
2697 if (candidates->next)
2699 /* Indent successive candidates by the width of the translation
2700 of the above string. */
2701 size_t len = gcc_gettext_width (str) + 1;
2702 char *spaces = (char *) alloca (len);
2703 memset (spaces, ' ', len-1);
2704 spaces[len - 1] = '\0';
2706 candidates = candidates->next;
2709 print_z_candidate (spaces, candidates);
2710 candidates = candidates->next;
2716 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2717 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2718 the result of the conversion function to convert it to the final
2719 desired type. Merge the two sequences into a single sequence,
2720 and return the merged sequence. */
2723 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2727 gcc_assert (user_seq->kind == ck_user);
2729 /* Find the end of the second conversion sequence. */
2731 while ((*t)->kind != ck_identity)
2732 t = &((*t)->u.next);
2734 /* Replace the identity conversion with the user conversion
2738 /* The entire sequence is a user-conversion sequence. */
2739 std_seq->user_conv_p = true;
2744 /* Returns the best overload candidate to perform the requested
2745 conversion. This function is used for three the overloading situations
2746 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2747 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2748 per [dcl.init.ref], so we ignore temporary bindings. */
2750 static struct z_candidate *
2751 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2753 struct z_candidate *candidates, *cand;
2754 tree fromtype = TREE_TYPE (expr);
2755 tree ctors = NULL_TREE;
2756 tree conv_fns = NULL_TREE;
2757 conversion *conv = NULL;
2758 tree first_arg = NULL_TREE;
2759 VEC(tree,gc) *args = NULL;
2763 /* We represent conversion within a hierarchy using RVALUE_CONV and
2764 BASE_CONV, as specified by [over.best.ics]; these become plain
2765 constructor calls, as specified in [dcl.init]. */
2766 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
2767 || !DERIVED_FROM_P (totype, fromtype));
2769 if (MAYBE_CLASS_TYPE_P (totype))
2770 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2772 if (MAYBE_CLASS_TYPE_P (fromtype))
2774 tree to_nonref = non_reference (totype);
2775 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
2776 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
2777 && DERIVED_FROM_P (to_nonref, fromtype)))
2779 /* [class.conv.fct] A conversion function is never used to
2780 convert a (possibly cv-qualified) object to the (possibly
2781 cv-qualified) same object type (or a reference to it), to a
2782 (possibly cv-qualified) base class of that type (or a
2783 reference to it)... */
2786 conv_fns = lookup_conversions (fromtype);
2790 flags |= LOOKUP_NO_CONVERSION;
2792 /* It's OK to bind a temporary for converting constructor arguments, but
2793 not in converting the return value of a conversion operator. */
2794 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
2795 flags &= ~LOOKUP_NO_TEMP_BIND;
2799 ctors = BASELINK_FUNCTIONS (ctors);
2801 first_arg = build_int_cst (build_pointer_type (totype), 0);
2802 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
2803 && !TYPE_HAS_LIST_CTOR (totype))
2805 args = ctor_to_vec (expr);
2806 /* We still allow more conversions within an init-list. */
2807 flags = ((flags & ~LOOKUP_NO_CONVERSION)
2808 /* But not for the copy ctor. */
2809 |LOOKUP_NO_COPY_CTOR_CONVERSION
2810 |LOOKUP_NO_NARROWING);
2813 args = make_tree_vector_single (expr);
2815 /* We should never try to call the abstract or base constructor
2817 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2818 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2820 for (; ctors; ctors = OVL_NEXT (ctors))
2822 tree ctor = OVL_CURRENT (ctors);
2823 if (DECL_NONCONVERTING_P (ctor)
2824 && !BRACE_ENCLOSED_INITIALIZER_P (expr))
2827 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2828 cand = add_template_candidate (&candidates, ctor, totype,
2829 NULL_TREE, first_arg, args, NULL_TREE,
2830 TYPE_BINFO (totype),
2831 TYPE_BINFO (totype),
2835 cand = add_function_candidate (&candidates, ctor, totype,
2836 first_arg, args, TYPE_BINFO (totype),
2837 TYPE_BINFO (totype),
2842 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2844 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2845 set, then this is copy-initialization. In that case, "The
2846 result of the call is then used to direct-initialize the
2847 object that is the destination of the copy-initialization."
2850 We represent this in the conversion sequence with an
2851 rvalue conversion, which means a constructor call. */
2852 if (TREE_CODE (totype) != REFERENCE_TYPE
2853 && !(convflags & LOOKUP_NO_TEMP_BIND))
2855 = build_conv (ck_rvalue, totype, cand->second_conv);
2860 first_arg = build_this (expr);
2862 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2865 tree conversion_path = TREE_PURPOSE (conv_fns);
2867 /* If we are called to convert to a reference type, we are trying to
2868 find an lvalue binding, so don't even consider temporaries. If
2869 we don't find an lvalue binding, the caller will try again to
2870 look for a temporary binding. */
2871 if (TREE_CODE (totype) == REFERENCE_TYPE)
2872 convflags |= LOOKUP_NO_TEMP_BIND;
2874 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2876 tree fn = OVL_CURRENT (fns);
2878 if (DECL_NONCONVERTING_P (fn)
2879 && (flags & LOOKUP_ONLYCONVERTING))
2882 /* [over.match.funcs] For conversion functions, the function
2883 is considered to be a member of the class of the implicit
2884 object argument for the purpose of defining the type of
2885 the implicit object parameter.
2887 So we pass fromtype as CTYPE to add_*_candidate. */
2889 if (TREE_CODE (fn) == TEMPLATE_DECL)
2890 cand = add_template_candidate (&candidates, fn, fromtype,
2892 first_arg, NULL, totype,
2893 TYPE_BINFO (fromtype),
2898 cand = add_function_candidate (&candidates, fn, fromtype,
2900 TYPE_BINFO (fromtype),
2907 = implicit_conversion (totype,
2908 TREE_TYPE (TREE_TYPE (cand->fn)),
2910 /*c_cast_p=*/false, convflags);
2912 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2913 copy-initialization. In that case, "The result of the
2914 call is then used to direct-initialize the object that is
2915 the destination of the copy-initialization." [dcl.init]
2917 We represent this in the conversion sequence with an
2918 rvalue conversion, which means a constructor call. But
2919 don't add a second rvalue conversion if there's already
2920 one there. Which there really shouldn't be, but it's
2921 harmless since we'd add it here anyway. */
2922 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
2923 && !(convflags & LOOKUP_NO_TEMP_BIND))
2924 ics = build_conv (ck_rvalue, totype, ics);
2926 cand->second_conv = ics;
2930 else if (candidates->viable == 1 && ics->bad_p)
2936 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2940 cand = tourney (candidates);
2943 if (flags & LOOKUP_COMPLAIN)
2945 error ("conversion from %qT to %qT is ambiguous",
2947 print_z_candidates (candidates);
2950 cand = candidates; /* any one will do */
2951 cand->second_conv = build_ambiguous_conv (totype, expr);
2952 cand->second_conv->user_conv_p = true;
2953 if (!any_strictly_viable (candidates))
2954 cand->second_conv->bad_p = true;
2955 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2956 ambiguous conversion is no worse than another user-defined
2962 /* Build the user conversion sequence. */
2965 (DECL_CONSTRUCTOR_P (cand->fn)
2966 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2967 build_identity_conv (TREE_TYPE (expr), expr));
2970 /* Remember that this was a list-initialization. */
2971 if (flags & LOOKUP_NO_NARROWING)
2972 conv->check_narrowing = true;
2974 /* Combine it with the second conversion sequence. */
2975 cand->second_conv = merge_conversion_sequences (conv,
2978 if (cand->viable == -1)
2979 cand->second_conv->bad_p = true;
2985 build_user_type_conversion (tree totype, tree expr, int flags)
2987 struct z_candidate *cand
2988 = build_user_type_conversion_1 (totype, expr, flags);
2992 if (cand->second_conv->kind == ck_ambig)
2993 return error_mark_node;
2994 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
2995 return convert_from_reference (expr);
3000 /* Do any initial processing on the arguments to a function call. */
3002 static VEC(tree,gc) *
3003 resolve_args (VEC(tree,gc) *args)
3008 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
3010 if (error_operand_p (arg))
3012 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3014 error ("invalid use of void expression");
3017 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3023 /* Perform overload resolution on FN, which is called with the ARGS.
3025 Return the candidate function selected by overload resolution, or
3026 NULL if the event that overload resolution failed. In the case
3027 that overload resolution fails, *CANDIDATES will be the set of
3028 candidates considered, and ANY_VIABLE_P will be set to true or
3029 false to indicate whether or not any of the candidates were
3032 The ARGS should already have gone through RESOLVE_ARGS before this
3033 function is called. */
3035 static struct z_candidate *
3036 perform_overload_resolution (tree fn,
3037 const VEC(tree,gc) *args,
3038 struct z_candidate **candidates,
3041 struct z_candidate *cand;
3042 tree explicit_targs = NULL_TREE;
3043 int template_only = 0;
3046 *any_viable_p = true;
3049 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3050 || TREE_CODE (fn) == TEMPLATE_DECL
3051 || TREE_CODE (fn) == OVERLOAD
3052 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3054 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3056 explicit_targs = TREE_OPERAND (fn, 1);
3057 fn = TREE_OPERAND (fn, 0);
3061 /* Add the various candidate functions. */
3062 add_candidates (fn, args, explicit_targs, template_only,
3063 /*conversion_path=*/NULL_TREE,
3064 /*access_path=*/NULL_TREE,
3068 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3072 cand = tourney (*candidates);
3076 /* Return an expression for a call to FN (a namespace-scope function,
3077 or a static member function) with the ARGS. This may change
3081 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3082 tsubst_flags_t complain)
3084 struct z_candidate *candidates, *cand;
3089 if (args != NULL && *args != NULL)
3091 *args = resolve_args (*args);
3093 return error_mark_node;
3096 /* If this function was found without using argument dependent
3097 lookup, then we want to ignore any undeclared friend
3103 fn = remove_hidden_names (fn);
3106 if (complain & tf_error)
3107 error ("no matching function for call to %<%D(%A)%>",
3108 DECL_NAME (OVL_CURRENT (orig_fn)),
3109 build_tree_list_vec (*args));
3110 return error_mark_node;
3114 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3115 p = conversion_obstack_alloc (0);
3117 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3121 if (complain & tf_error)
3123 if (!any_viable_p && candidates && ! candidates->next)
3124 return cp_build_function_call_vec (candidates->fn, args, complain);
3125 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3126 fn = TREE_OPERAND (fn, 0);
3128 error ("no matching function for call to %<%D(%A)%>",
3129 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3131 error ("call of overloaded %<%D(%A)%> is ambiguous",
3132 DECL_NAME (OVL_CURRENT (fn)), build_tree_list_vec (*args));
3134 print_z_candidates (candidates);
3136 result = error_mark_node;
3139 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3141 /* Free all the conversions we allocated. */
3142 obstack_free (&conversion_obstack, p);
3147 /* Build a call to a global operator new. FNNAME is the name of the
3148 operator (either "operator new" or "operator new[]") and ARGS are
3149 the arguments provided. This may change ARGS. *SIZE points to the
3150 total number of bytes required by the allocation, and is updated if
3151 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3152 be used. If this function determines that no cookie should be
3153 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3154 non-NULL, it will be set, upon return, to the allocation function
3158 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3159 tree *size, tree *cookie_size,
3163 struct z_candidate *candidates;
3164 struct z_candidate *cand;
3169 VEC_safe_insert (tree, gc, *args, 0, *size);
3170 *args = resolve_args (*args);
3172 return error_mark_node;
3178 If this lookup fails to find the name, or if the allocated type
3179 is not a class type, the allocation function's name is looked
3180 up in the global scope.
3182 we disregard block-scope declarations of "operator new". */
3183 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3185 /* Figure out what function is being called. */
3186 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3188 /* If no suitable function could be found, issue an error message
3193 error ("no matching function for call to %<%D(%A)%>",
3194 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3196 error ("call of overloaded %<%D(%A)%> is ambiguous",
3197 DECL_NAME (OVL_CURRENT (fns)), build_tree_list_vec (*args));
3199 print_z_candidates (candidates);
3200 return error_mark_node;
3203 /* If a cookie is required, add some extra space. Whether
3204 or not a cookie is required cannot be determined until
3205 after we know which function was called. */
3208 bool use_cookie = true;
3209 if (!abi_version_at_least (2))
3211 /* In G++ 3.2, the check was implemented incorrectly; it
3212 looked at the placement expression, rather than the
3213 type of the function. */
3214 if (VEC_length (tree, *args) == 2
3215 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3223 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3224 /* Skip the size_t parameter. */
3225 arg_types = TREE_CHAIN (arg_types);
3226 /* Check the remaining parameters (if any). */
3228 && TREE_CHAIN (arg_types) == void_list_node
3229 && same_type_p (TREE_VALUE (arg_types),
3233 /* If we need a cookie, adjust the number of bytes allocated. */
3236 /* Update the total size. */
3237 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3238 /* Update the argument list to reflect the adjusted size. */
3239 VEC_replace (tree, *args, 0, *size);
3242 *cookie_size = NULL_TREE;
3245 /* Tell our caller which function we decided to call. */
3249 /* Build the CALL_EXPR. */
3250 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3253 /* Build a new call to operator(). This may change ARGS. */
3256 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3258 struct z_candidate *candidates = 0, *cand;
3259 tree fns, convs, first_mem_arg = NULL_TREE;
3260 tree type = TREE_TYPE (obj);
3262 tree result = NULL_TREE;
3265 if (error_operand_p (obj))
3266 return error_mark_node;
3268 obj = prep_operand (obj);
3270 if (TYPE_PTRMEMFUNC_P (type))
3272 if (complain & tf_error)
3273 /* It's no good looking for an overloaded operator() on a
3274 pointer-to-member-function. */
3275 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3276 return error_mark_node;
3279 if (TYPE_BINFO (type))
3281 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3282 if (fns == error_mark_node)
3283 return error_mark_node;
3288 if (args != NULL && *args != NULL)
3290 *args = resolve_args (*args);
3292 return error_mark_node;
3295 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3296 p = conversion_obstack_alloc (0);
3300 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3301 first_mem_arg = build_this (obj);
3303 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3305 tree fn = OVL_CURRENT (fns);
3306 if (TREE_CODE (fn) == TEMPLATE_DECL)
3307 add_template_candidate (&candidates, fn, base, NULL_TREE,
3308 first_mem_arg, *args, NULL_TREE,
3311 LOOKUP_NORMAL, DEDUCE_CALL);
3313 add_function_candidate
3314 (&candidates, fn, base, first_mem_arg, *args, TYPE_BINFO (type),
3315 TYPE_BINFO (type), LOOKUP_NORMAL);
3319 convs = lookup_conversions (type);
3321 for (; convs; convs = TREE_CHAIN (convs))
3323 tree fns = TREE_VALUE (convs);
3324 tree totype = TREE_TYPE (convs);
3326 if ((TREE_CODE (totype) == POINTER_TYPE
3327 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3328 || (TREE_CODE (totype) == REFERENCE_TYPE
3329 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3330 || (TREE_CODE (totype) == REFERENCE_TYPE
3331 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3332 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3333 for (; fns; fns = OVL_NEXT (fns))
3335 tree fn = OVL_CURRENT (fns);
3337 if (DECL_NONCONVERTING_P (fn))
3340 if (TREE_CODE (fn) == TEMPLATE_DECL)
3341 add_template_conv_candidate
3342 (&candidates, fn, obj, NULL_TREE, *args, totype,
3343 /*access_path=*/NULL_TREE,
3344 /*conversion_path=*/NULL_TREE);
3346 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3347 *args, /*conversion_path=*/NULL_TREE,
3348 /*access_path=*/NULL_TREE);
3352 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3355 if (complain & tf_error)
3357 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3358 build_tree_list_vec (*args));
3359 print_z_candidates (candidates);
3361 result = error_mark_node;
3365 cand = tourney (candidates);
3368 if (complain & tf_error)
3370 error ("call of %<(%T) (%A)%> is ambiguous",
3371 TREE_TYPE (obj), build_tree_list_vec (*args));
3372 print_z_candidates (candidates);
3374 result = error_mark_node;
3376 /* Since cand->fn will be a type, not a function, for a conversion
3377 function, we must be careful not to unconditionally look at
3379 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3380 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3381 result = build_over_call (cand, LOOKUP_NORMAL, complain);
3384 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
3386 obj = convert_from_reference (obj);
3387 result = cp_build_function_call_vec (obj, args, complain);
3391 /* Free all the conversions we allocated. */
3392 obstack_free (&conversion_obstack, p);
3398 op_error (enum tree_code code, enum tree_code code2,
3399 tree arg1, tree arg2, tree arg3, const char *problem)
3403 if (code == MODIFY_EXPR)
3404 opname = assignment_operator_name_info[code2].name;
3406 opname = operator_name_info[code].name;
3411 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3412 problem, arg1, arg2, arg3);
3415 case POSTINCREMENT_EXPR:
3416 case POSTDECREMENT_EXPR:
3417 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3421 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3426 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3431 error ("%s for %<operator%s%> in %<%E %s %E%>",
3432 problem, opname, arg1, opname, arg2);
3434 error ("%s for %<operator%s%> in %<%s%E%>",
3435 problem, opname, opname, arg1);
3440 /* Return the implicit conversion sequence that could be used to
3441 convert E1 to E2 in [expr.cond]. */
3444 conditional_conversion (tree e1, tree e2)
3446 tree t1 = non_reference (TREE_TYPE (e1));
3447 tree t2 = non_reference (TREE_TYPE (e2));
3453 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3454 implicitly converted (clause _conv_) to the type "reference to
3455 T2", subject to the constraint that in the conversion the
3456 reference must bind directly (_dcl.init.ref_) to E1. */
3457 if (real_lvalue_p (e2))
3459 conv = implicit_conversion (build_reference_type (t2),
3463 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
3470 If E1 and E2 have class type, and the underlying class types are
3471 the same or one is a base class of the other: E1 can be converted
3472 to match E2 if the class of T2 is the same type as, or a base
3473 class of, the class of T1, and the cv-qualification of T2 is the
3474 same cv-qualification as, or a greater cv-qualification than, the
3475 cv-qualification of T1. If the conversion is applied, E1 is
3476 changed to an rvalue of type T2 that still refers to the original
3477 source class object (or the appropriate subobject thereof). */
3478 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3479 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3481 if (good_base && at_least_as_qualified_p (t2, t1))
3483 conv = build_identity_conv (t1, e1);
3484 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3485 TYPE_MAIN_VARIANT (t2)))
3486 conv = build_conv (ck_base, t2, conv);
3488 conv = build_conv (ck_rvalue, t2, conv);
3497 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3498 converted to the type that expression E2 would have if E2 were
3499 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3500 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3504 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3505 arguments to the conditional expression. */
3508 build_conditional_expr (tree arg1, tree arg2, tree arg3,
3509 tsubst_flags_t complain)
3513 tree result = NULL_TREE;
3514 tree result_type = NULL_TREE;
3515 bool lvalue_p = true;
3516 struct z_candidate *candidates = 0;
3517 struct z_candidate *cand;
3520 /* As a G++ extension, the second argument to the conditional can be
3521 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3522 c'.) If the second operand is omitted, make sure it is
3523 calculated only once. */
3526 if (complain & tf_error)
3527 pedwarn (input_location, OPT_pedantic,
3528 "ISO C++ forbids omitting the middle term of a ?: expression");
3530 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3531 if (real_lvalue_p (arg1))
3532 arg2 = arg1 = stabilize_reference (arg1);
3534 arg2 = arg1 = save_expr (arg1);
3539 The first expression is implicitly converted to bool (clause
3541 arg1 = perform_implicit_conversion (boolean_type_node, arg1, complain);
3543 /* If something has already gone wrong, just pass that fact up the
3545 if (error_operand_p (arg1)
3546 || error_operand_p (arg2)
3547 || error_operand_p (arg3))
3548 return error_mark_node;
3552 If either the second or the third operand has type (possibly
3553 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3554 array-to-pointer (_conv.array_), and function-to-pointer
3555 (_conv.func_) standard conversions are performed on the second
3556 and third operands. */
3557 arg2_type = unlowered_expr_type (arg2);
3558 arg3_type = unlowered_expr_type (arg3);
3559 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3561 /* Do the conversions. We don't these for `void' type arguments
3562 since it can't have any effect and since decay_conversion
3563 does not handle that case gracefully. */
3564 if (!VOID_TYPE_P (arg2_type))
3565 arg2 = decay_conversion (arg2);
3566 if (!VOID_TYPE_P (arg3_type))
3567 arg3 = decay_conversion (arg3);
3568 arg2_type = TREE_TYPE (arg2);
3569 arg3_type = TREE_TYPE (arg3);
3573 One of the following shall hold:
3575 --The second or the third operand (but not both) is a
3576 throw-expression (_except.throw_); the result is of the
3577 type of the other and is an rvalue.
3579 --Both the second and the third operands have type void; the
3580 result is of type void and is an rvalue.
3582 We must avoid calling force_rvalue for expressions of type
3583 "void" because it will complain that their value is being
3585 if (TREE_CODE (arg2) == THROW_EXPR
3586 && TREE_CODE (arg3) != THROW_EXPR)
3588 if (!VOID_TYPE_P (arg3_type))
3589 arg3 = force_rvalue (arg3);
3590 arg3_type = TREE_TYPE (arg3);
3591 result_type = arg3_type;
3593 else if (TREE_CODE (arg2) != THROW_EXPR
3594 && TREE_CODE (arg3) == THROW_EXPR)
3596 if (!VOID_TYPE_P (arg2_type))
3597 arg2 = force_rvalue (arg2);
3598 arg2_type = TREE_TYPE (arg2);
3599 result_type = arg2_type;
3601 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3602 result_type = void_type_node;
3605 if (complain & tf_error)
3607 if (VOID_TYPE_P (arg2_type))
3608 error ("second operand to the conditional operator "
3609 "is of type %<void%>, "
3610 "but the third operand is neither a throw-expression "
3611 "nor of type %<void%>");
3613 error ("third operand to the conditional operator "
3614 "is of type %<void%>, "
3615 "but the second operand is neither a throw-expression "
3616 "nor of type %<void%>");
3618 return error_mark_node;
3622 goto valid_operands;
3626 Otherwise, if the second and third operand have different types,
3627 and either has (possibly cv-qualified) class type, an attempt is
3628 made to convert each of those operands to the type of the other. */
3629 else if (!same_type_p (arg2_type, arg3_type)
3630 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3635 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3636 p = conversion_obstack_alloc (0);
3638 conv2 = conditional_conversion (arg2, arg3);
3639 conv3 = conditional_conversion (arg3, arg2);
3643 If both can be converted, or one can be converted but the
3644 conversion is ambiguous, the program is ill-formed. If
3645 neither can be converted, the operands are left unchanged and
3646 further checking is performed as described below. If exactly
3647 one conversion is possible, that conversion is applied to the
3648 chosen operand and the converted operand is used in place of
3649 the original operand for the remainder of this section. */
3650 if ((conv2 && !conv2->bad_p
3651 && conv3 && !conv3->bad_p)
3652 || (conv2 && conv2->kind == ck_ambig)
3653 || (conv3 && conv3->kind == ck_ambig))
3655 error ("operands to ?: have different types %qT and %qT",
3656 arg2_type, arg3_type);
3657 result = error_mark_node;
3659 else if (conv2 && (!conv2->bad_p || !conv3))
3661 arg2 = convert_like (conv2, arg2, complain);
3662 arg2 = convert_from_reference (arg2);
3663 arg2_type = TREE_TYPE (arg2);
3664 /* Even if CONV2 is a valid conversion, the result of the
3665 conversion may be invalid. For example, if ARG3 has type
3666 "volatile X", and X does not have a copy constructor
3667 accepting a "volatile X&", then even if ARG2 can be
3668 converted to X, the conversion will fail. */
3669 if (error_operand_p (arg2))
3670 result = error_mark_node;
3672 else if (conv3 && (!conv3->bad_p || !conv2))
3674 arg3 = convert_like (conv3, arg3, complain);
3675 arg3 = convert_from_reference (arg3);
3676 arg3_type = TREE_TYPE (arg3);
3677 if (error_operand_p (arg3))
3678 result = error_mark_node;
3681 /* Free all the conversions we allocated. */
3682 obstack_free (&conversion_obstack, p);
3687 /* If, after the conversion, both operands have class type,
3688 treat the cv-qualification of both operands as if it were the
3689 union of the cv-qualification of the operands.
3691 The standard is not clear about what to do in this
3692 circumstance. For example, if the first operand has type
3693 "const X" and the second operand has a user-defined
3694 conversion to "volatile X", what is the type of the second
3695 operand after this step? Making it be "const X" (matching
3696 the first operand) seems wrong, as that discards the
3697 qualification without actually performing a copy. Leaving it
3698 as "volatile X" seems wrong as that will result in the
3699 conditional expression failing altogether, even though,
3700 according to this step, the one operand could be converted to
3701 the type of the other. */
3702 if ((conv2 || conv3)
3703 && CLASS_TYPE_P (arg2_type)
3704 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3705 arg2_type = arg3_type =
3706 cp_build_qualified_type (arg2_type,
3707 TYPE_QUALS (arg2_type)
3708 | TYPE_QUALS (arg3_type));
3713 If the second and third operands are lvalues and have the same
3714 type, the result is of that type and is an lvalue. */
3715 if (real_lvalue_p (arg2)
3716 && real_lvalue_p (arg3)
3717 && same_type_p (arg2_type, arg3_type))
3719 result_type = arg2_type;
3720 goto valid_operands;
3725 Otherwise, the result is an rvalue. If the second and third
3726 operand do not have the same type, and either has (possibly
3727 cv-qualified) class type, overload resolution is used to
3728 determine the conversions (if any) to be applied to the operands
3729 (_over.match.oper_, _over.built_). */
3731 if (!same_type_p (arg2_type, arg3_type)
3732 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3738 /* Rearrange the arguments so that add_builtin_candidate only has
3739 to know about two args. In build_builtin_candidates, the
3740 arguments are unscrambled. */
3744 add_builtin_candidates (&candidates,
3747 ansi_opname (COND_EXPR),
3753 If the overload resolution fails, the program is
3755 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3758 if (complain & tf_error)
3760 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3761 print_z_candidates (candidates);
3763 return error_mark_node;
3765 cand = tourney (candidates);
3768 if (complain & tf_error)
3770 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3771 print_z_candidates (candidates);
3773 return error_mark_node;
3778 Otherwise, the conversions thus determined are applied, and
3779 the converted operands are used in place of the original
3780 operands for the remainder of this section. */
3781 conv = cand->convs[0];
3782 arg1 = convert_like (conv, arg1, complain);
3783 conv = cand->convs[1];
3784 arg2 = convert_like (conv, arg2, complain);
3785 conv = cand->convs[2];
3786 arg3 = convert_like (conv, arg3, complain);
3791 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3792 and function-to-pointer (_conv.func_) standard conversions are
3793 performed on the second and third operands.
3795 We need to force the lvalue-to-rvalue conversion here for class types,
3796 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3797 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3800 arg2 = force_rvalue (arg2);
3801 if (!CLASS_TYPE_P (arg2_type))
3802 arg2_type = TREE_TYPE (arg2);
3804 arg3 = force_rvalue (arg3);
3805 if (!CLASS_TYPE_P (arg2_type))
3806 arg3_type = TREE_TYPE (arg3);
3808 if (arg2 == error_mark_node || arg3 == error_mark_node)
3809 return error_mark_node;
3813 After those conversions, one of the following shall hold:
3815 --The second and third operands have the same type; the result is of
3817 if (same_type_p (arg2_type, arg3_type))
3818 result_type = arg2_type;
3821 --The second and third operands have arithmetic or enumeration
3822 type; the usual arithmetic conversions are performed to bring
3823 them to a common type, and the result is of that type. */
3824 else if ((ARITHMETIC_TYPE_P (arg2_type)
3825 || UNSCOPED_ENUM_P (arg2_type))
3826 && (ARITHMETIC_TYPE_P (arg3_type)
3827 || UNSCOPED_ENUM_P (arg3_type)))
3829 /* In this case, there is always a common type. */
3830 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3833 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3834 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3836 if (complain & tf_warning)
3838 "enumeral mismatch in conditional expression: %qT vs %qT",
3839 arg2_type, arg3_type);
3841 else if (extra_warnings
3842 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3843 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3844 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3845 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3847 if (complain & tf_warning)
3849 "enumeral and non-enumeral type in conditional expression");
3852 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3853 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3857 --The second and third operands have pointer type, or one has
3858 pointer type and the other is a null pointer constant; pointer
3859 conversions (_conv.ptr_) and qualification conversions
3860 (_conv.qual_) are performed to bring them to their composite
3861 pointer type (_expr.rel_). The result is of the composite
3864 --The second and third operands have pointer to member type, or
3865 one has pointer to member type and the other is a null pointer
3866 constant; pointer to member conversions (_conv.mem_) and
3867 qualification conversions (_conv.qual_) are performed to bring
3868 them to a common type, whose cv-qualification shall match the
3869 cv-qualification of either the second or the third operand.
3870 The result is of the common type. */
3871 else if ((null_ptr_cst_p (arg2)
3872 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3873 || (null_ptr_cst_p (arg3)
3874 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3875 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3876 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3877 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3879 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3880 arg3, "conditional expression",
3882 if (result_type == error_mark_node)
3883 return error_mark_node;
3884 arg2 = perform_implicit_conversion (result_type, arg2, complain);
3885 arg3 = perform_implicit_conversion (result_type, arg3, complain);
3890 if (complain & tf_error)
3891 error ("operands to ?: have different types %qT and %qT",
3892 arg2_type, arg3_type);
3893 return error_mark_node;
3897 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3899 /* We can't use result_type below, as fold might have returned a
3904 /* Expand both sides into the same slot, hopefully the target of
3905 the ?: expression. We used to check for TARGET_EXPRs here,
3906 but now we sometimes wrap them in NOP_EXPRs so the test would
3908 if (CLASS_TYPE_P (TREE_TYPE (result)))
3909 result = get_target_expr (result);
3910 /* If this expression is an rvalue, but might be mistaken for an
3911 lvalue, we must add a NON_LVALUE_EXPR. */
3912 result = rvalue (result);
3918 /* OPERAND is an operand to an expression. Perform necessary steps
3919 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3923 prep_operand (tree operand)
3927 if (CLASS_TYPE_P (TREE_TYPE (operand))
3928 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3929 /* Make sure the template type is instantiated now. */
3930 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3936 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3937 OVERLOAD) to the CANDIDATES, returning an updated list of
3938 CANDIDATES. The ARGS are the arguments provided to the call,
3939 without any implicit object parameter. This may change ARGS. The
3940 EXPLICIT_TARGS are explicit template arguments provided.
3941 TEMPLATE_ONLY is true if only template functions should be
3942 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
3943 add_function_candidate. */
3946 add_candidates (tree fns, const VEC(tree,gc) *args,
3947 tree explicit_targs, bool template_only,
3948 tree conversion_path, tree access_path,
3950 struct z_candidate **candidates)
3953 VEC(tree,gc) *non_static_args;
3956 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3957 /* Delay creating the implicit this parameter until it is needed. */
3958 non_static_args = NULL;
3959 first_arg = NULL_TREE;
3965 const VEC(tree,gc) *fn_args;
3967 fn = OVL_CURRENT (fns);
3968 /* Figure out which set of arguments to use. */
3969 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3971 /* If this function is a non-static member, prepend the implicit
3972 object parameter. */
3973 if (non_static_args == NULL)
3978 non_static_args = VEC_alloc (tree, gc,
3979 VEC_length (tree, args) - 1);
3980 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
3981 VEC_quick_push (tree, non_static_args, arg);
3983 if (first_arg == NULL_TREE)
3984 first_arg = build_this (VEC_index (tree, args, 0));
3985 fn_first_arg = first_arg;
3986 fn_args = non_static_args;
3990 /* Otherwise, just use the list of arguments provided. */
3991 fn_first_arg = NULL_TREE;
3995 if (TREE_CODE (fn) == TEMPLATE_DECL)
3996 add_template_candidate (candidates,
4007 else if (!template_only)
4008 add_function_candidate (candidates,
4016 fns = OVL_NEXT (fns);
4021 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4022 bool *overloaded_p, tsubst_flags_t complain)
4024 struct z_candidate *candidates = 0, *cand;
4025 VEC(tree,gc) *arglist;
4028 tree result = NULL_TREE;
4029 bool result_valid_p = false;
4030 enum tree_code code2 = NOP_EXPR;
4031 enum tree_code code_orig_arg1 = ERROR_MARK;
4032 enum tree_code code_orig_arg2 = ERROR_MARK;
4038 if (error_operand_p (arg1)
4039 || error_operand_p (arg2)
4040 || error_operand_p (arg3))
4041 return error_mark_node;
4043 if (code == MODIFY_EXPR)
4045 code2 = TREE_CODE (arg3);
4047 fnname = ansi_assopname (code2);
4050 fnname = ansi_opname (code);
4052 arg1 = prep_operand (arg1);
4058 case VEC_DELETE_EXPR:
4060 /* Use build_op_new_call and build_op_delete_call instead. */
4064 /* Use build_op_call instead. */
4067 case TRUTH_ORIF_EXPR:
4068 case TRUTH_ANDIF_EXPR:
4069 case TRUTH_AND_EXPR:
4071 /* These are saved for the sake of warn_logical_operator. */
4072 code_orig_arg1 = TREE_CODE (arg1);
4073 code_orig_arg2 = TREE_CODE (arg2);
4079 arg2 = prep_operand (arg2);
4080 arg3 = prep_operand (arg3);
4082 if (code == COND_EXPR)
4084 if (arg2 == NULL_TREE
4085 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
4086 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
4087 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
4088 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
4091 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4092 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4095 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4096 arg2 = integer_zero_node;
4098 arglist = VEC_alloc (tree, gc, 3);
4099 VEC_quick_push (tree, arglist, arg1);
4100 if (arg2 != NULL_TREE)
4101 VEC_quick_push (tree, arglist, arg2);
4102 if (arg3 != NULL_TREE)
4103 VEC_quick_push (tree, arglist, arg3);
4105 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4106 p = conversion_obstack_alloc (0);
4108 /* Add namespace-scope operators to the list of functions to
4110 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4111 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
4112 flags, &candidates);
4113 /* Add class-member operators to the candidate set. */
4114 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4118 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4119 if (fns == error_mark_node)
4121 result = error_mark_node;
4122 goto user_defined_result_ready;
4125 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
4127 BASELINK_BINFO (fns),
4128 TYPE_BINFO (TREE_TYPE (arg1)),
4129 flags, &candidates);
4132 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
4133 to know about two args; a builtin candidate will always have a first
4134 parameter of type bool. We'll handle that in
4135 build_builtin_candidate. */
4136 if (code == COND_EXPR)
4146 args[2] = NULL_TREE;
4149 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4155 /* For these, the built-in candidates set is empty
4156 [over.match.oper]/3. We don't want non-strict matches
4157 because exact matches are always possible with built-in
4158 operators. The built-in candidate set for COMPONENT_REF
4159 would be empty too, but since there are no such built-in
4160 operators, we accept non-strict matches for them. */
4165 strict_p = pedantic;
4169 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4174 case POSTINCREMENT_EXPR:
4175 case POSTDECREMENT_EXPR:
4176 /* Don't try anything fancy if we're not allowed to produce
4178 if (!(complain & tf_error))
4179 return error_mark_node;
4181 /* Look for an `operator++ (int)'. If they didn't have
4182 one, then we fall back to the old way of doing things. */
4183 if (flags & LOOKUP_COMPLAIN)
4184 permerror (input_location, "no %<%D(int)%> declared for postfix %qs, "
4185 "trying prefix operator instead",
4187 operator_name_info[code].name);
4188 if (code == POSTINCREMENT_EXPR)
4189 code = PREINCREMENT_EXPR;
4191 code = PREDECREMENT_EXPR;
4192 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
4193 overloaded_p, complain);
4196 /* The caller will deal with these. */
4201 result_valid_p = true;
4205 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4207 /* If one of the arguments of the operator represents
4208 an invalid use of member function pointer, try to report
4209 a meaningful error ... */
4210 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4211 || invalid_nonstatic_memfn_p (arg2, tf_error)
4212 || invalid_nonstatic_memfn_p (arg3, tf_error))
4213 /* We displayed the error message. */;
4216 /* ... Otherwise, report the more generic
4217 "no matching operator found" error */
4218 op_error (code, code2, arg1, arg2, arg3, "no match");
4219 print_z_candidates (candidates);
4222 result = error_mark_node;
4228 cand = tourney (candidates);
4231 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4233 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
4234 print_z_candidates (candidates);
4236 result = error_mark_node;
4238 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
4241 *overloaded_p = true;
4243 if (resolve_args (arglist) == NULL)
4244 result = error_mark_node;
4246 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4250 /* Give any warnings we noticed during overload resolution. */
4251 if (cand->warnings && (complain & tf_warning))
4253 struct candidate_warning *w;
4254 for (w = cand->warnings; w; w = w->next)
4255 joust (cand, w->loser, 1);
4258 /* Check for comparison of different enum types. */
4267 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
4268 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
4269 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
4270 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
4271 && (complain & tf_warning))
4273 warning (OPT_Wenum_compare,
4274 "comparison between %q#T and %q#T",
4275 TREE_TYPE (arg1), TREE_TYPE (arg2));
4282 /* We need to strip any leading REF_BIND so that bitfields
4283 don't cause errors. This should not remove any important
4284 conversions, because builtins don't apply to class
4285 objects directly. */
4286 conv = cand->convs[0];
4287 if (conv->kind == ck_ref_bind)
4288 conv = conv->u.next;
4289 arg1 = convert_like (conv, arg1, complain);
4293 /* We need to call warn_logical_operator before
4294 converting arg2 to a boolean_type. */
4295 if (complain & tf_warning)
4296 warn_logical_operator (input_location, code, boolean_type_node,
4297 code_orig_arg1, arg1,
4298 code_orig_arg2, arg2);
4300 conv = cand->convs[1];
4301 if (conv->kind == ck_ref_bind)
4302 conv = conv->u.next;
4303 arg2 = convert_like (conv, arg2, complain);
4307 conv = cand->convs[2];
4308 if (conv->kind == ck_ref_bind)
4309 conv = conv->u.next;
4310 arg3 = convert_like (conv, arg3, complain);
4316 user_defined_result_ready:
4318 /* Free all the conversions we allocated. */
4319 obstack_free (&conversion_obstack, p);
4321 if (result || result_valid_p)
4328 return cp_build_modify_expr (arg1, code2, arg2, complain);
4331 return cp_build_indirect_ref (arg1, "unary *", complain);
4333 case TRUTH_ANDIF_EXPR:
4334 case TRUTH_ORIF_EXPR:
4335 case TRUTH_AND_EXPR:
4337 warn_logical_operator (input_location, code, boolean_type_node,
4338 code_orig_arg1, arg1, code_orig_arg2, arg2);
4343 case TRUNC_DIV_EXPR:
4354 case TRUNC_MOD_EXPR:
4358 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
4360 case UNARY_PLUS_EXPR:
4363 case TRUTH_NOT_EXPR:
4364 case PREINCREMENT_EXPR:
4365 case POSTINCREMENT_EXPR:
4366 case PREDECREMENT_EXPR:
4367 case POSTDECREMENT_EXPR:
4370 return cp_build_unary_op (code, arg1, candidates != 0, complain);
4373 return build_array_ref (arg1, arg2, input_location);
4376 return build_conditional_expr (arg1, arg2, arg3, complain);
4379 return build_m_component_ref (cp_build_indirect_ref (arg1, NULL,
4383 /* The caller will deal with these. */
4395 /* Build a call to operator delete. This has to be handled very specially,
4396 because the restrictions on what signatures match are different from all
4397 other call instances. For a normal delete, only a delete taking (void *)
4398 or (void *, size_t) is accepted. For a placement delete, only an exact
4399 match with the placement new is accepted.
4401 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4402 ADDR is the pointer to be deleted.
4403 SIZE is the size of the memory block to be deleted.
4404 GLOBAL_P is true if the delete-expression should not consider
4405 class-specific delete operators.
4406 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4408 If this call to "operator delete" is being generated as part to
4409 deallocate memory allocated via a new-expression (as per [expr.new]
4410 which requires that if the initialization throws an exception then
4411 we call a deallocation function), then ALLOC_FN is the allocation
4415 build_op_delete_call (enum tree_code code, tree addr, tree size,
4416 bool global_p, tree placement,
4419 tree fn = NULL_TREE;
4420 tree fns, fnname, argtypes, type;
4423 if (addr == error_mark_node)
4424 return error_mark_node;
4426 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4428 fnname = ansi_opname (code);
4430 if (CLASS_TYPE_P (type)
4431 && COMPLETE_TYPE_P (complete_type (type))
4435 If the result of the lookup is ambiguous or inaccessible, or if
4436 the lookup selects a placement deallocation function, the
4437 program is ill-formed.
4439 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4441 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4442 if (fns == error_mark_node)
4443 return error_mark_node;
4448 if (fns == NULL_TREE)
4449 fns = lookup_name_nonclass (fnname);
4451 /* Strip const and volatile from addr. */
4452 addr = cp_convert (ptr_type_node, addr);
4456 /* Get the parameter types for the allocation function that is
4458 gcc_assert (alloc_fn != NULL_TREE);
4459 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4463 /* First try it without the size argument. */
4464 argtypes = void_list_node;
4467 /* We make two tries at finding a matching `operator delete'. On
4468 the first pass, we look for a one-operator (or placement)
4469 operator delete. If we're not doing placement delete, then on
4470 the second pass we look for a two-argument delete. */
4471 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4473 /* Go through the `operator delete' functions looking for one
4474 with a matching type. */
4475 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4481 /* The first argument must be "void *". */
4482 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4483 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4486 /* On the first pass, check the rest of the arguments. */
4492 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4500 /* On the second pass, look for a function with exactly two
4501 arguments: "void *" and "size_t". */
4503 /* For "operator delete(void *, ...)" there will be
4504 no second argument, but we will not get an exact
4507 && same_type_p (TREE_VALUE (t), size_type_node)
4508 && TREE_CHAIN (t) == void_list_node)
4512 /* If we found a match, we're done. */
4517 /* If we have a matching function, call it. */
4520 /* Make sure we have the actual function, and not an
4522 fn = OVL_CURRENT (fn);
4524 /* If the FN is a member function, make sure that it is
4526 if (DECL_CLASS_SCOPE_P (fn))
4527 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4531 /* The placement args might not be suitable for overload
4532 resolution at this point, so build the call directly. */
4533 int nargs = call_expr_nargs (placement);
4534 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4537 for (i = 1; i < nargs; i++)
4538 argarray[i] = CALL_EXPR_ARG (placement, i);
4540 return build_cxx_call (fn, nargs, argarray);
4545 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
4546 VEC_quick_push (tree, args, addr);
4548 VEC_quick_push (tree, args, size);
4549 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
4550 VEC_free (tree, gc, args);
4557 If no unambiguous matching deallocation function can be found,
4558 propagating the exception does not cause the object's memory to
4563 warning (0, "no corresponding deallocation function for %qD",
4568 error ("no suitable %<operator %s%> for %qT",
4569 operator_name_info[(int)code].name, type);
4570 return error_mark_node;
4573 /* If the current scope isn't allowed to access DECL along
4574 BASETYPE_PATH, give an error. The most derived class in
4575 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4576 the declaration to use in the error diagnostic. */
4579 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4581 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4583 if (!accessible_p (basetype_path, decl, true))
4585 if (TREE_PRIVATE (decl))
4586 error ("%q+#D is private", diag_decl);
4587 else if (TREE_PROTECTED (decl))
4588 error ("%q+#D is protected", diag_decl);
4590 error ("%q+#D is inaccessible", diag_decl);
4591 error ("within this context");
4598 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4599 bitwise or of LOOKUP_* values. If any errors are warnings are
4600 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4601 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4605 build_temp (tree expr, tree type, int flags,
4606 diagnostic_t *diagnostic_kind)
4611 savew = warningcount, savee = errorcount;
4612 args = make_tree_vector_single (expr);
4613 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4614 &args, type, flags, tf_warning_or_error);
4615 release_tree_vector (args);
4616 if (warningcount > savew)
4617 *diagnostic_kind = DK_WARNING;
4618 else if (errorcount > savee)
4619 *diagnostic_kind = DK_ERROR;
4621 *diagnostic_kind = DK_UNSPECIFIED;
4625 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4626 EXPR is implicitly converted to type TOTYPE.
4627 FN and ARGNUM are used for diagnostics. */
4630 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4632 tree t = non_reference (totype);
4634 /* Issue warnings about peculiar, but valid, uses of NULL. */
4635 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4638 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4641 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4644 /* Issue warnings if "false" is converted to a NULL pointer */
4645 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4646 warning (OPT_Wconversion,
4647 "converting %<false%> to pointer type for argument %P of %qD",
4651 /* Perform the conversions in CONVS on the expression EXPR. FN and
4652 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4653 indicates the `this' argument of a method. INNER is nonzero when
4654 being called to continue a conversion chain. It is negative when a
4655 reference binding will be applied, positive otherwise. If
4656 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4657 conversions will be emitted if appropriate. If C_CAST_P is true,
4658 this conversion is coming from a C-style cast; in that case,
4659 conversions to inaccessible bases are permitted. */
4662 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4663 int inner, bool issue_conversion_warnings,
4664 bool c_cast_p, tsubst_flags_t complain)
4666 tree totype = convs->type;
4667 diagnostic_t diag_kind;
4671 && convs->kind != ck_user
4672 && convs->kind != ck_ambig
4673 && convs->kind != ck_ref_bind
4674 && convs->kind != ck_rvalue
4675 && convs->kind != ck_base)
4677 conversion *t = convs;
4678 for (; t; t = convs->u.next)
4680 if (t->kind == ck_user || !t->bad_p)
4682 expr = convert_like_real (t, expr, fn, argnum, 1,
4683 /*issue_conversion_warnings=*/false,
4688 else if (t->kind == ck_ambig)
4689 return convert_like_real (t, expr, fn, argnum, 1,
4690 /*issue_conversion_warnings=*/false,
4693 else if (t->kind == ck_identity)
4696 if (complain & tf_error)
4698 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4700 permerror (input_location, " initializing argument %P of %qD", argnum, fn);
4703 return error_mark_node;
4705 return cp_convert (totype, expr);
4708 if (issue_conversion_warnings && (complain & tf_warning))
4709 conversion_null_warnings (totype, expr, fn, argnum);
4711 switch (convs->kind)
4715 struct z_candidate *cand = convs->cand;
4716 tree convfn = cand->fn;
4719 /* When converting from an init list we consider explicit
4720 constructors, but actually trying to call one is an error. */
4721 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn))
4723 if (complain & tf_error)
4724 error ("converting to %qT from initializer list would use "
4725 "explicit constructor %qD", totype, convfn);
4727 return error_mark_node;
4730 /* Set user_conv_p on the argument conversions, so rvalue/base
4731 handling knows not to allow any more UDCs. */
4732 for (i = 0; i < cand->num_convs; ++i)
4733 cand->convs[i]->user_conv_p = true;
4735 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
4737 /* If this is a constructor or a function returning an aggr type,
4738 we need to build up a TARGET_EXPR. */
4739 if (DECL_CONSTRUCTOR_P (convfn))
4741 expr = build_cplus_new (totype, expr);
4743 /* Remember that this was list-initialization. */
4744 if (convs->check_narrowing)
4745 TARGET_EXPR_LIST_INIT_P (expr) = true;
4751 if (type_unknown_p (expr))
4752 expr = instantiate_type (totype, expr, complain);
4753 /* Convert a constant to its underlying value, unless we are
4754 about to bind it to a reference, in which case we need to
4755 leave it as an lvalue. */
4758 expr = decl_constant_value (expr);
4759 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
4760 /* If __null has been converted to an integer type, we do not
4761 want to warn about uses of EXPR as an integer, rather than
4763 expr = build_int_cst (totype, 0);
4767 /* Call build_user_type_conversion again for the error. */
4768 return build_user_type_conversion
4769 (totype, convs->u.expr, LOOKUP_NORMAL);
4773 /* Conversion to std::initializer_list<T>. */
4774 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
4775 tree new_ctor = build_constructor (init_list_type_node, NULL);
4776 unsigned len = CONSTRUCTOR_NELTS (expr);
4778 VEC(tree,gc) *parms;
4781 /* Convert all the elements. */
4782 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
4784 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
4785 1, false, false, complain);
4786 if (sub == error_mark_node)
4788 check_narrowing (TREE_TYPE (sub), val);
4789 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
4791 /* Build up the array. */
4792 elttype = cp_build_qualified_type
4793 (elttype, TYPE_QUALS (elttype) | TYPE_QUAL_CONST);
4794 array = build_array_of_n_type (elttype, len);
4795 array = finish_compound_literal (array, new_ctor);
4797 parms = make_tree_vector ();
4798 VEC_safe_push (tree, gc, parms, decay_conversion (array));
4799 VEC_safe_push (tree, gc, parms, size_int (len));
4800 /* Call the private constructor. */
4801 push_deferring_access_checks (dk_no_check);
4802 new_ctor = build_special_member_call
4803 (NULL_TREE, complete_ctor_identifier, &parms, totype, 0, complain);
4804 release_tree_vector (parms);
4805 pop_deferring_access_checks ();
4806 return build_cplus_new (totype, new_ctor);
4810 return get_target_expr (digest_init (totype, expr));
4816 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4817 convs->kind == ck_ref_bind ? -1 : 1,
4818 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4821 if (expr == error_mark_node)
4822 return error_mark_node;
4824 switch (convs->kind)
4827 expr = convert_bitfield_to_declared_type (expr);
4828 if (! MAYBE_CLASS_TYPE_P (totype))
4830 /* Else fall through. */
4832 if (convs->kind == ck_base && !convs->need_temporary_p)
4834 /* We are going to bind a reference directly to a base-class
4835 subobject of EXPR. */
4836 /* Build an expression for `*((base*) &expr)'. */
4837 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
4838 expr = convert_to_base (expr, build_pointer_type (totype),
4839 !c_cast_p, /*nonnull=*/true);
4840 expr = cp_build_indirect_ref (expr, "implicit conversion", complain);
4844 /* Copy-initialization where the cv-unqualified version of the source
4845 type is the same class as, or a derived class of, the class of the
4846 destination [is treated as direct-initialization]. [dcl.init] */
4847 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
4848 if (convs->user_conv_p)
4849 /* This conversion is being done in the context of a user-defined
4850 conversion (i.e. the second step of copy-initialization), so
4851 don't allow any more. */
4852 flags |= LOOKUP_NO_CONVERSION;
4853 expr = build_temp (expr, totype, flags, &diag_kind);
4854 if (diag_kind && fn)
4856 if ((complain & tf_error))
4857 emit_diagnostic (diag_kind, input_location, 0,
4858 " initializing argument %P of %qD", argnum, fn);
4859 else if (diag_kind == DK_ERROR)
4860 return error_mark_node;
4862 return build_cplus_new (totype, expr);
4866 tree ref_type = totype;
4868 /* If necessary, create a temporary.
4870 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4871 that need temporaries, even when their types are reference
4872 compatible with the type of reference being bound, so the
4873 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
4875 if (convs->need_temporary_p
4876 || TREE_CODE (expr) == CONSTRUCTOR
4877 || TREE_CODE (expr) == VA_ARG_EXPR)
4879 tree type = convs->u.next->type;
4880 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4882 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
4883 && !TYPE_REF_IS_RVALUE (ref_type))
4885 if (complain & tf_error)
4887 /* If the reference is volatile or non-const, we
4888 cannot create a temporary. */
4889 if (lvalue & clk_bitfield)
4890 error ("cannot bind bitfield %qE to %qT",
4892 else if (lvalue & clk_packed)
4893 error ("cannot bind packed field %qE to %qT",
4896 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4898 return error_mark_node;
4900 /* If the source is a packed field, and we must use a copy
4901 constructor, then building the target expr will require
4902 binding the field to the reference parameter to the
4903 copy constructor, and we'll end up with an infinite
4904 loop. If we can use a bitwise copy, then we'll be
4906 if ((lvalue & clk_packed)
4907 && CLASS_TYPE_P (type)
4908 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4910 if (complain & tf_error)
4911 error ("cannot bind packed field %qE to %qT",
4913 return error_mark_node;
4915 if (lvalue & clk_bitfield)
4917 expr = convert_bitfield_to_declared_type (expr);
4918 expr = fold_convert (type, expr);
4920 expr = build_target_expr_with_type (expr, type);
4923 /* Take the address of the thing to which we will bind the
4925 expr = cp_build_unary_op (ADDR_EXPR, expr, 1, complain);
4926 if (expr == error_mark_node)
4927 return error_mark_node;
4929 /* Convert it to a pointer to the type referred to by the
4930 reference. This will adjust the pointer if a derived to
4931 base conversion is being performed. */
4932 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4934 /* Convert the pointer to the desired reference type. */
4935 return build_nop (ref_type, expr);
4939 return decay_conversion (expr);
4942 /* Warn about deprecated conversion if appropriate. */
4943 string_conv_p (totype, expr, 1);
4948 expr = convert_to_base (expr, totype, !c_cast_p,
4950 return build_nop (totype, expr);
4953 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4960 if (convs->check_narrowing)
4961 check_narrowing (totype, expr);
4963 if (issue_conversion_warnings && (complain & tf_warning))
4964 expr = convert_and_check (totype, expr);
4966 expr = convert (totype, expr);
4971 /* Build a call to __builtin_trap. */
4974 call_builtin_trap (void)
4976 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4978 gcc_assert (fn != NULL);
4979 fn = build_call_n (fn, 0);
4983 /* ARG is being passed to a varargs function. Perform any conversions
4984 required. Return the converted value. */
4987 convert_arg_to_ellipsis (tree arg)
4991 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4992 standard conversions are performed. */
4993 arg = decay_conversion (arg);
4996 If the argument has integral or enumeration type that is subject
4997 to the integral promotions (_conv.prom_), or a floating point
4998 type that is subject to the floating point promotion
4999 (_conv.fpprom_), the value of the argument is converted to the
5000 promoted type before the call. */
5001 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
5002 && (TYPE_PRECISION (TREE_TYPE (arg))
5003 < TYPE_PRECISION (double_type_node)))
5004 arg = convert_to_real (double_type_node, arg);
5005 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
5006 arg = perform_integral_promotions (arg);
5008 arg = require_complete_type (arg);
5010 if (arg != error_mark_node
5011 && !pod_type_p (TREE_TYPE (arg)))
5013 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
5014 here and do a bitwise copy, but now cp_expr_size will abort if we
5016 If the call appears in the context of a sizeof expression,
5017 there is no need to emit a warning, since the expression won't be
5018 evaluated. We keep the builtin_trap just as a safety check. */
5019 if (!skip_evaluation)
5020 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
5021 "call will abort at runtime", TREE_TYPE (arg));
5022 arg = call_builtin_trap ();
5023 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
5030 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5033 build_x_va_arg (tree expr, tree type)
5035 if (processing_template_decl)
5036 return build_min (VA_ARG_EXPR, type, expr);
5038 type = complete_type_or_else (type, NULL_TREE);
5040 if (expr == error_mark_node || !type)
5041 return error_mark_node;
5043 if (! pod_type_p (type))
5045 /* Remove reference types so we don't ICE later on. */
5046 tree type1 = non_reference (type);
5047 /* Undefined behavior [expr.call] 5.2.2/7. */
5048 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
5049 "call will abort at runtime", type);
5050 expr = convert (build_pointer_type (type1), null_node);
5051 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
5052 call_builtin_trap (), expr);
5053 expr = cp_build_indirect_ref (expr, NULL, tf_warning_or_error);
5057 return build_va_arg (expr, type);
5060 /* TYPE has been given to va_arg. Apply the default conversions which
5061 would have happened when passed via ellipsis. Return the promoted
5062 type, or the passed type if there is no change. */
5065 cxx_type_promotes_to (tree type)
5069 /* Perform the array-to-pointer and function-to-pointer
5071 type = type_decays_to (type);
5073 promote = type_promotes_to (type);
5074 if (same_type_p (type, promote))
5080 /* ARG is a default argument expression being passed to a parameter of
5081 the indicated TYPE, which is a parameter to FN. Do any required
5082 conversions. Return the converted value. */
5084 static GTY(()) VEC(tree,gc) *default_arg_context;
5087 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
5092 /* If the ARG is an unparsed default argument expression, the
5093 conversion cannot be performed. */
5094 if (TREE_CODE (arg) == DEFAULT_ARG)
5096 error ("the default argument for parameter %d of %qD has "
5097 "not yet been parsed",
5099 return error_mark_node;
5102 /* Detect recursion. */
5103 for (i = 0; VEC_iterate (tree, default_arg_context, i, t); ++i)
5106 error ("recursive evaluation of default argument for %q#D", fn);
5107 return error_mark_node;
5109 VEC_safe_push (tree, gc, default_arg_context, fn);
5111 if (fn && DECL_TEMPLATE_INFO (fn))
5112 arg = tsubst_default_argument (fn, type, arg);
5118 The names in the expression are bound, and the semantic
5119 constraints are checked, at the point where the default
5120 expressions appears.
5122 we must not perform access checks here. */
5123 push_deferring_access_checks (dk_no_check);
5124 arg = break_out_target_exprs (arg);
5125 if (TREE_CODE (arg) == CONSTRUCTOR)
5127 arg = digest_init (type, arg);
5128 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5129 "default argument", fn, parmnum,
5130 tf_warning_or_error);
5134 /* We must make a copy of ARG, in case subsequent processing
5135 alters any part of it. For example, during gimplification a
5136 cast of the form (T) &X::f (where "f" is a member function)
5137 will lead to replacing the PTRMEM_CST for &X::f with a
5138 VAR_DECL. We can avoid the copy for constants, since they
5139 are never modified in place. */
5140 if (!CONSTANT_CLASS_P (arg))
5141 arg = unshare_expr (arg);
5142 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
5143 "default argument", fn, parmnum,
5144 tf_warning_or_error);
5145 arg = convert_for_arg_passing (type, arg);
5147 pop_deferring_access_checks();
5149 VEC_pop (tree, default_arg_context);
5154 /* Returns the type which will really be used for passing an argument of
5158 type_passed_as (tree type)
5160 /* Pass classes with copy ctors by invisible reference. */
5161 if (TREE_ADDRESSABLE (type))
5163 type = build_reference_type (type);
5164 /* There are no other pointers to this temporary. */
5165 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
5167 else if (targetm.calls.promote_prototypes (type)
5168 && INTEGRAL_TYPE_P (type)
5169 && COMPLETE_TYPE_P (type)
5170 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5171 TYPE_SIZE (integer_type_node)))
5172 type = integer_type_node;
5177 /* Actually perform the appropriate conversion. */
5180 convert_for_arg_passing (tree type, tree val)
5184 /* If VAL is a bitfield, then -- since it has already been converted
5185 to TYPE -- it cannot have a precision greater than TYPE.
5187 If it has a smaller precision, we must widen it here. For
5188 example, passing "int f:3;" to a function expecting an "int" will
5189 not result in any conversion before this point.
5191 If the precision is the same we must not risk widening. For
5192 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5193 often have type "int", even though the C++ type for the field is
5194 "long long". If the value is being passed to a function
5195 expecting an "int", then no conversions will be required. But,
5196 if we call convert_bitfield_to_declared_type, the bitfield will
5197 be converted to "long long". */
5198 bitfield_type = is_bitfield_expr_with_lowered_type (val);
5200 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
5201 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
5203 if (val == error_mark_node)
5205 /* Pass classes with copy ctors by invisible reference. */
5206 else if (TREE_ADDRESSABLE (type))
5207 val = build1 (ADDR_EXPR, build_reference_type (type), val);
5208 else if (targetm.calls.promote_prototypes (type)
5209 && INTEGRAL_TYPE_P (type)
5210 && COMPLETE_TYPE_P (type)
5211 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
5212 TYPE_SIZE (integer_type_node)))
5213 val = perform_integral_promotions (val);
5214 if (warn_missing_format_attribute)
5216 tree rhstype = TREE_TYPE (val);
5217 const enum tree_code coder = TREE_CODE (rhstype);
5218 const enum tree_code codel = TREE_CODE (type);
5219 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5221 && check_missing_format_attribute (type, rhstype))
5222 warning (OPT_Wmissing_format_attribute,
5223 "argument of function call might be a candidate for a format attribute");
5228 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5229 which no conversions at all should be done. This is true for some
5230 builtins which don't act like normal functions. */
5233 magic_varargs_p (tree fn)
5235 if (DECL_BUILT_IN (fn))
5236 switch (DECL_FUNCTION_CODE (fn))
5238 case BUILT_IN_CLASSIFY_TYPE:
5239 case BUILT_IN_CONSTANT_P:
5240 case BUILT_IN_NEXT_ARG:
5241 case BUILT_IN_VA_START:
5245 return lookup_attribute ("type generic",
5246 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
5252 /* Subroutine of the various build_*_call functions. Overload resolution
5253 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5254 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5255 bitmask of various LOOKUP_* flags which apply to the call itself. */
5258 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
5261 const VEC(tree,gc) *args = cand->args;
5262 tree first_arg = cand->first_arg;
5263 conversion **convs = cand->convs;
5265 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
5270 unsigned int arg_index = 0;
5274 bool already_used = false;
5276 /* In a template, there is no need to perform all of the work that
5277 is normally done. We are only interested in the type of the call
5278 expression, i.e., the return type of the function. Any semantic
5279 errors will be deferred until the template is instantiated. */
5280 if (processing_template_decl)
5284 const tree *argarray;
5287 return_type = TREE_TYPE (TREE_TYPE (fn));
5288 nargs = VEC_length (tree, args);
5289 if (first_arg == NULL_TREE)
5290 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
5298 alcarray = XALLOCAVEC (tree, nargs);
5299 alcarray[0] = first_arg;
5300 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
5301 alcarray[ix + 1] = arg;
5302 argarray = alcarray;
5304 expr = build_call_array (return_type, build_addr_func (fn), nargs,
5306 if (TREE_THIS_VOLATILE (fn) && cfun)
5307 current_function_returns_abnormally = 1;
5308 if (!VOID_TYPE_P (return_type))
5309 require_complete_type (return_type);
5310 return convert_from_reference (expr);
5313 /* Give any warnings we noticed during overload resolution. */
5316 struct candidate_warning *w;
5317 for (w = cand->warnings; w; w = w->next)
5318 joust (cand, w->loser, 1);
5321 /* Make =delete work with SFINAE. */
5322 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
5323 return error_mark_node;
5325 if (DECL_FUNCTION_MEMBER_P (fn))
5327 /* If FN is a template function, two cases must be considered.
5332 template <class T> void f();
5334 template <class T> struct B {
5338 struct C : A, B<int> {
5340 using B<int>::g; // #2
5343 In case #1 where `A::f' is a member template, DECL_ACCESS is
5344 recorded in the primary template but not in its specialization.
5345 We check access of FN using its primary template.
5347 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5348 because it is a member of class template B, DECL_ACCESS is
5349 recorded in the specialization `B<int>::g'. We cannot use its
5350 primary template because `B<T>::g' and `B<int>::g' may have
5351 different access. */
5352 if (DECL_TEMPLATE_INFO (fn)
5353 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
5354 perform_or_defer_access_check (cand->access_path,
5355 DECL_TI_TEMPLATE (fn), fn);
5357 perform_or_defer_access_check (cand->access_path, fn, fn);
5360 /* Find maximum size of vector to hold converted arguments. */
5361 parmlen = list_length (parm);
5362 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
5363 if (parmlen > nargs)
5365 argarray = (tree *) alloca (nargs * sizeof (tree));
5367 /* The implicit parameters to a constructor are not considered by overload
5368 resolution, and must be of the proper type. */
5369 if (DECL_CONSTRUCTOR_P (fn))
5371 if (first_arg != NULL_TREE)
5373 argarray[j++] = first_arg;
5374 first_arg = NULL_TREE;
5378 argarray[j++] = VEC_index (tree, args, arg_index);
5381 parm = TREE_CHAIN (parm);
5382 /* We should never try to call the abstract constructor. */
5383 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
5385 if (DECL_HAS_VTT_PARM_P (fn))
5387 argarray[j++] = VEC_index (tree, args, arg_index);
5389 parm = TREE_CHAIN (parm);
5392 /* Bypass access control for 'this' parameter. */
5393 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5395 tree parmtype = TREE_VALUE (parm);
5396 tree arg = (first_arg != NULL_TREE
5398 : VEC_index (tree, args, arg_index));
5399 tree argtype = TREE_TYPE (arg);
5403 if (convs[i]->bad_p)
5405 if (complain & tf_error)
5406 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
5407 TREE_TYPE (argtype), fn);
5409 return error_mark_node;
5412 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5413 X is called for an object that is not of type X, or of a type
5414 derived from X, the behavior is undefined.
5416 So we can assume that anything passed as 'this' is non-null, and
5417 optimize accordingly. */
5418 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
5419 /* Convert to the base in which the function was declared. */
5420 gcc_assert (cand->conversion_path != NULL_TREE);
5421 converted_arg = build_base_path (PLUS_EXPR,
5423 cand->conversion_path,
5425 /* Check that the base class is accessible. */
5426 if (!accessible_base_p (TREE_TYPE (argtype),
5427 BINFO_TYPE (cand->conversion_path), true))
5428 error ("%qT is not an accessible base of %qT",
5429 BINFO_TYPE (cand->conversion_path),
5430 TREE_TYPE (argtype));
5431 /* If fn was found by a using declaration, the conversion path
5432 will be to the derived class, not the base declaring fn. We
5433 must convert from derived to base. */
5434 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
5435 TREE_TYPE (parmtype), ba_unique, NULL);
5436 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
5439 argarray[j++] = converted_arg;
5440 parm = TREE_CHAIN (parm);
5441 if (first_arg != NULL_TREE)
5442 first_arg = NULL_TREE;
5449 gcc_assert (first_arg == NULL_TREE);
5450 for (; arg_index < VEC_length (tree, args) && parm;
5451 parm = TREE_CHAIN (parm), ++arg_index, ++i)
5453 tree type = TREE_VALUE (parm);
5457 /* Don't make a copy here if build_call is going to. */
5458 if (conv->kind == ck_rvalue
5459 && COMPLETE_TYPE_P (complete_type (type))
5460 && !TREE_ADDRESSABLE (type))
5461 conv = conv->u.next;
5463 val = convert_like_with_context
5464 (conv, VEC_index (tree, args, arg_index), fn, i - is_method,
5467 val = convert_for_arg_passing (type, val);
5468 if (val == error_mark_node)
5469 return error_mark_node;
5471 argarray[j++] = val;
5474 /* Default arguments */
5475 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
5476 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
5477 TREE_PURPOSE (parm),
5480 for (; arg_index < VEC_length (tree, args); ++arg_index)
5482 tree a = VEC_index (tree, args, arg_index);
5483 if (magic_varargs_p (fn))
5484 /* Do no conversions for magic varargs. */;
5486 a = convert_arg_to_ellipsis (a);
5490 gcc_assert (j <= nargs);
5493 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
5494 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5496 /* Avoid actually calling copy constructors and copy assignment operators,
5499 if (! flag_elide_constructors)
5500 /* Do things the hard way. */;
5501 else if (cand->num_convs == 1
5502 && (DECL_COPY_CONSTRUCTOR_P (fn)
5503 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5506 tree arg = argarray[num_artificial_parms_for (fn)];
5509 /* Pull out the real argument, disregarding const-correctness. */
5511 while (CONVERT_EXPR_P (targ)
5512 || TREE_CODE (targ) == NON_LVALUE_EXPR)
5513 targ = TREE_OPERAND (targ, 0);
5514 if (TREE_CODE (targ) == ADDR_EXPR)
5516 targ = TREE_OPERAND (targ, 0);
5517 if (!same_type_ignoring_top_level_qualifiers_p
5518 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5527 arg = cp_build_indirect_ref (arg, 0, complain);
5529 if (TREE_CODE (arg) == TARGET_EXPR
5530 && TARGET_EXPR_LIST_INIT_P (arg))
5532 /* Copy-list-initialization doesn't require the copy constructor
5535 /* [class.copy]: the copy constructor is implicitly defined even if
5536 the implementation elided its use. */
5537 else if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5540 already_used = true;
5543 /* If we're creating a temp and we already have one, don't create a
5544 new one. If we're not creating a temp but we get one, use
5545 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5546 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5547 temp or an INIT_EXPR otherwise. */
5548 fa = (cand->first_arg != NULL_TREE
5550 : VEC_index (tree, args, 0));
5551 if (integer_zerop (fa))
5553 if (TREE_CODE (arg) == TARGET_EXPR)
5555 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5556 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5558 else if (TREE_CODE (arg) == TARGET_EXPR
5559 || (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn))
5560 && !move_fn_p (fn)))
5562 tree to = stabilize_reference (cp_build_indirect_ref (fa, 0,
5565 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5569 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5571 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5573 tree to = stabilize_reference
5574 (cp_build_indirect_ref (argarray[0], 0, complain));
5575 tree type = TREE_TYPE (to);
5576 tree as_base = CLASSTYPE_AS_BASE (type);
5577 tree arg = argarray[1];
5579 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5581 arg = cp_build_indirect_ref (arg, 0, complain);
5582 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5586 /* We must only copy the non-tail padding parts.
5587 Use __builtin_memcpy for the bitwise copy.
5588 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5589 instead of an explicit call to memcpy. */
5591 tree arg0, arg1, arg2, t;
5592 tree test = NULL_TREE;
5594 arg2 = TYPE_SIZE_UNIT (as_base);
5596 arg0 = cp_build_unary_op (ADDR_EXPR, to, 0, complain);
5598 if (!(optimize && flag_tree_ter))
5600 /* When TER is off get_pointer_alignment returns 0, so a call
5601 to __builtin_memcpy is expanded as a call to memcpy, which
5602 is invalid with identical args. When TER is on it is
5603 expanded as a block move, which should be safe. */
5604 arg0 = save_expr (arg0);
5605 arg1 = save_expr (arg1);
5606 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
5608 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5609 t = build_call_n (t, 3, arg0, arg1, arg2);
5611 t = convert (TREE_TYPE (arg0), t);
5613 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
5614 val = cp_build_indirect_ref (t, 0, complain);
5615 TREE_NO_WARNING (val) = 1;
5624 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5627 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5630 gcc_assert (binfo && binfo != error_mark_node);
5632 /* Warn about deprecated virtual functions now, since we're about
5633 to throw away the decl. */
5634 if (TREE_DEPRECATED (fn))
5635 warn_deprecated_use (fn, NULL_TREE);
5637 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5638 if (TREE_SIDE_EFFECTS (argarray[0]))
5639 argarray[0] = save_expr (argarray[0]);
5640 t = build_pointer_type (TREE_TYPE (fn));
5641 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5642 fn = build_java_interface_fn_ref (fn, argarray[0]);
5644 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5648 fn = build_addr_func (fn);
5650 return build_cxx_call (fn, nargs, argarray);
5653 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5654 This function performs no overload resolution, conversion, or other
5655 high-level operations. */
5658 build_cxx_call (tree fn, int nargs, tree *argarray)
5662 fn = build_call_a (fn, nargs, argarray);
5664 /* If this call might throw an exception, note that fact. */
5665 fndecl = get_callee_fndecl (fn);
5666 if ((!fndecl || !TREE_NOTHROW (fndecl))
5667 && at_function_scope_p ()
5669 cp_function_chain->can_throw = 1;
5671 /* Check that arguments to builtin functions match the expectations. */
5673 && DECL_BUILT_IN (fndecl)
5674 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5675 && !check_builtin_function_arguments (fndecl, nargs, argarray))
5676 return error_mark_node;
5678 /* Some built-in function calls will be evaluated at compile-time in
5680 fn = fold_if_not_in_template (fn);
5682 if (VOID_TYPE_P (TREE_TYPE (fn)))
5685 fn = require_complete_type (fn);
5686 if (fn == error_mark_node)
5687 return error_mark_node;
5689 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
5690 fn = build_cplus_new (TREE_TYPE (fn), fn);
5691 return convert_from_reference (fn);
5694 static GTY(()) tree java_iface_lookup_fn;
5696 /* Make an expression which yields the address of the Java interface
5697 method FN. This is achieved by generating a call to libjava's
5698 _Jv_LookupInterfaceMethodIdx(). */
5701 build_java_interface_fn_ref (tree fn, tree instance)
5703 tree lookup_fn, method, idx;
5704 tree klass_ref, iface, iface_ref;
5707 if (!java_iface_lookup_fn)
5709 tree endlink = build_void_list_node ();
5710 tree t = tree_cons (NULL_TREE, ptr_type_node,
5711 tree_cons (NULL_TREE, ptr_type_node,
5712 tree_cons (NULL_TREE, java_int_type_node,
5714 java_iface_lookup_fn
5715 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5716 build_function_type (ptr_type_node, t),
5717 0, NOT_BUILT_IN, NULL, NULL_TREE);
5720 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5721 This is the first entry in the vtable. */
5722 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, 0,
5723 tf_warning_or_error),
5726 /* Get the java.lang.Class pointer for the interface being called. */
5727 iface = DECL_CONTEXT (fn);
5728 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5729 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5730 || DECL_CONTEXT (iface_ref) != iface)
5732 error ("could not find class$ field in java interface type %qT",
5734 return error_mark_node;
5736 iface_ref = build_address (iface_ref);
5737 iface_ref = convert (build_pointer_type (iface), iface_ref);
5739 /* Determine the itable index of FN. */
5741 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5743 if (!DECL_VIRTUAL_P (method))
5749 idx = build_int_cst (NULL_TREE, i);
5751 lookup_fn = build1 (ADDR_EXPR,
5752 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5753 java_iface_lookup_fn);
5754 return build_call_nary (ptr_type_node, lookup_fn,
5755 3, klass_ref, iface_ref, idx);
5758 /* Returns the value to use for the in-charge parameter when making a
5759 call to a function with the indicated NAME.
5761 FIXME:Can't we find a neater way to do this mapping? */
5764 in_charge_arg_for_name (tree name)
5766 if (name == base_ctor_identifier
5767 || name == base_dtor_identifier)
5768 return integer_zero_node;
5769 else if (name == complete_ctor_identifier)
5770 return integer_one_node;
5771 else if (name == complete_dtor_identifier)
5772 return integer_two_node;
5773 else if (name == deleting_dtor_identifier)
5774 return integer_three_node;
5776 /* This function should only be called with one of the names listed
5782 /* Build a call to a constructor, destructor, or an assignment
5783 operator for INSTANCE, an expression with class type. NAME
5784 indicates the special member function to call; *ARGS are the
5785 arguments. ARGS may be NULL. This may change ARGS. BINFO
5786 indicates the base of INSTANCE that is to be passed as the `this'
5787 parameter to the member function called.
5789 FLAGS are the LOOKUP_* flags to use when processing the call.
5791 If NAME indicates a complete object constructor, INSTANCE may be
5792 NULL_TREE. In this case, the caller will call build_cplus_new to
5793 store the newly constructed object into a VAR_DECL. */
5796 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
5797 tree binfo, int flags, tsubst_flags_t complain)
5800 /* The type of the subobject to be constructed or destroyed. */
5802 VEC(tree,gc) *allocated = NULL;
5805 gcc_assert (name == complete_ctor_identifier
5806 || name == base_ctor_identifier
5807 || name == complete_dtor_identifier
5808 || name == base_dtor_identifier
5809 || name == deleting_dtor_identifier
5810 || name == ansi_assopname (NOP_EXPR));
5813 /* Resolve the name. */
5814 if (!complete_type_or_else (binfo, NULL_TREE))
5815 return error_mark_node;
5817 binfo = TYPE_BINFO (binfo);
5820 gcc_assert (binfo != NULL_TREE);
5822 class_type = BINFO_TYPE (binfo);
5824 /* Handle the special case where INSTANCE is NULL_TREE. */
5825 if (name == complete_ctor_identifier && !instance)
5827 instance = build_int_cst (build_pointer_type (class_type), 0);
5828 instance = build1 (INDIRECT_REF, class_type, instance);
5832 if (name == complete_dtor_identifier
5833 || name == base_dtor_identifier
5834 || name == deleting_dtor_identifier)
5835 gcc_assert (args == NULL || VEC_empty (tree, *args));
5837 /* Convert to the base class, if necessary. */
5838 if (!same_type_ignoring_top_level_qualifiers_p
5839 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5841 if (name != ansi_assopname (NOP_EXPR))
5842 /* For constructors and destructors, either the base is
5843 non-virtual, or it is virtual but we are doing the
5844 conversion from a constructor or destructor for the
5845 complete object. In either case, we can convert
5847 instance = convert_to_base_statically (instance, binfo);
5849 /* However, for assignment operators, we must convert
5850 dynamically if the base is virtual. */
5851 instance = build_base_path (PLUS_EXPR, instance,
5852 binfo, /*nonnull=*/1);
5856 gcc_assert (instance != NULL_TREE);
5858 fns = lookup_fnfields (binfo, name, 1);
5860 /* When making a call to a constructor or destructor for a subobject
5861 that uses virtual base classes, pass down a pointer to a VTT for
5863 if ((name == base_ctor_identifier
5864 || name == base_dtor_identifier)
5865 && CLASSTYPE_VBASECLASSES (class_type))
5870 /* If the current function is a complete object constructor
5871 or destructor, then we fetch the VTT directly.
5872 Otherwise, we look it up using the VTT we were given. */
5873 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5874 vtt = decay_conversion (vtt);
5875 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5876 build2 (EQ_EXPR, boolean_type_node,
5877 current_in_charge_parm, integer_zero_node),
5880 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5881 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
5882 BINFO_SUBVTT_INDEX (binfo));
5886 allocated = make_tree_vector ();
5890 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
5893 ret = build_new_method_call (instance, fns, args,
5894 TYPE_BINFO (BINFO_TYPE (binfo)),
5898 if (allocated != NULL)
5899 release_tree_vector (allocated);
5904 /* Return the NAME, as a C string. The NAME indicates a function that
5905 is a member of TYPE. *FREE_P is set to true if the caller must
5906 free the memory returned.
5908 Rather than go through all of this, we should simply set the names
5909 of constructors and destructors appropriately, and dispense with
5910 ctor_identifier, dtor_identifier, etc. */
5913 name_as_c_string (tree name, tree type, bool *free_p)
5917 /* Assume that we will not allocate memory. */
5919 /* Constructors and destructors are special. */
5920 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5923 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
5924 /* For a destructor, add the '~'. */
5925 if (name == complete_dtor_identifier
5926 || name == base_dtor_identifier
5927 || name == deleting_dtor_identifier)
5929 pretty_name = concat ("~", pretty_name, NULL);
5930 /* Remember that we need to free the memory allocated. */
5934 else if (IDENTIFIER_TYPENAME_P (name))
5936 pretty_name = concat ("operator ",
5937 type_as_string_translate (TREE_TYPE (name),
5938 TFF_PLAIN_IDENTIFIER),
5940 /* Remember that we need to free the memory allocated. */
5944 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
5949 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
5950 be set, upon return, to the function called. ARGS may be NULL.
5951 This may change ARGS. */
5954 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
5955 tree conversion_path, int flags,
5956 tree *fn_p, tsubst_flags_t complain)
5958 struct z_candidate *candidates = 0, *cand;
5959 tree explicit_targs = NULL_TREE;
5960 tree basetype = NULL_TREE;
5963 tree first_mem_arg = NULL_TREE;
5966 bool skip_first_for_error;
5967 VEC(tree,gc) *user_args;
5971 int template_only = 0;
5975 VEC(tree,gc) *orig_args = NULL;
5978 gcc_assert (instance != NULL_TREE);
5980 /* We don't know what function we're going to call, yet. */
5984 if (error_operand_p (instance)
5985 || error_operand_p (fns))
5986 return error_mark_node;
5988 if (!BASELINK_P (fns))
5990 if (complain & tf_error)
5991 error ("call to non-function %qD", fns);
5992 return error_mark_node;
5995 orig_instance = instance;
5998 /* Dismantle the baselink to collect all the information we need. */
5999 if (!conversion_path)
6000 conversion_path = BASELINK_BINFO (fns);
6001 access_binfo = BASELINK_ACCESS_BINFO (fns);
6002 optype = BASELINK_OPTYPE (fns);
6003 fns = BASELINK_FUNCTIONS (fns);
6004 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
6006 explicit_targs = TREE_OPERAND (fns, 1);
6007 fns = TREE_OPERAND (fns, 0);
6010 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
6011 || TREE_CODE (fns) == TEMPLATE_DECL
6012 || TREE_CODE (fns) == OVERLOAD);
6013 fn = get_first_fn (fns);
6014 name = DECL_NAME (fn);
6016 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
6017 gcc_assert (CLASS_TYPE_P (basetype));
6019 if (processing_template_decl)
6021 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
6022 instance = build_non_dependent_expr (instance);
6024 make_args_non_dependent (*args);
6027 /* Figure out whether to skip the first argument for the error
6028 message we will display to users if an error occurs. We don't
6029 want to display any compiler-generated arguments. The "this"
6030 pointer hasn't been added yet. However, we must remove the VTT
6031 pointer if this is a call to a base-class constructor or
6033 skip_first_for_error = false;
6034 user_args = args == NULL ? NULL : *args;
6035 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6037 /* Callers should explicitly indicate whether they want to construct
6038 the complete object or just the part without virtual bases. */
6039 gcc_assert (name != ctor_identifier);
6040 /* Similarly for destructors. */
6041 gcc_assert (name != dtor_identifier);
6042 /* Remove the VTT pointer, if present. */
6043 if ((name == base_ctor_identifier || name == base_dtor_identifier)
6044 && CLASSTYPE_VBASECLASSES (basetype))
6045 skip_first_for_error = true;
6048 /* Process the argument list. */
6049 if (args != NULL && *args != NULL)
6051 *args = resolve_args (*args);
6053 return error_mark_node;
6056 instance_ptr = build_this (instance);
6058 /* It's OK to call destructors and constructors on cv-qualified objects.
6059 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6061 if (DECL_DESTRUCTOR_P (fn)
6062 || DECL_CONSTRUCTOR_P (fn))
6064 tree type = build_pointer_type (basetype);
6065 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
6066 instance_ptr = build_nop (type, instance_ptr);
6068 if (DECL_DESTRUCTOR_P (fn))
6069 name = complete_dtor_identifier;
6071 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6072 initializer, not T({ }). If the type doesn't have a list ctor,
6073 break apart the list into separate ctor args. */
6074 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
6075 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
6076 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0))
6077 && !TYPE_HAS_LIST_CTOR (basetype))
6079 gcc_assert (VEC_length (tree, *args) == 1);
6080 *args = ctor_to_vec (VEC_index (tree, *args, 0));
6083 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
6084 first_mem_arg = instance_ptr;
6086 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6087 p = conversion_obstack_alloc (0);
6089 for (fn = fns; fn; fn = OVL_NEXT (fn))
6091 tree t = OVL_CURRENT (fn);
6092 tree this_first_arg;
6094 /* We can end up here for copy-init of same or base class. */
6095 if ((flags & LOOKUP_ONLYCONVERTING)
6096 && DECL_NONCONVERTING_P (t))
6099 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
6100 this_first_arg = first_mem_arg;
6102 this_first_arg = NULL_TREE;
6104 if (TREE_CODE (t) == TEMPLATE_DECL)
6105 /* A member template. */
6106 add_template_candidate (&candidates, t,
6110 args == NULL ? NULL : *args,
6116 else if (! template_only)
6117 add_function_candidate (&candidates, t,
6120 args == NULL ? NULL : *args,
6126 candidates = splice_viable (candidates, pedantic, &any_viable_p);
6129 if (complain & tf_error)
6131 if (!COMPLETE_TYPE_P (basetype))
6132 cxx_incomplete_type_error (instance_ptr, basetype);
6139 pretty_name = name_as_c_string (name, basetype, &free_p);
6140 arglist = build_tree_list_vec (user_args);
6141 if (skip_first_for_error)
6142 arglist = TREE_CHAIN (arglist);
6143 error ("no matching function for call to %<%T::%s(%A)%#V%>",
6144 basetype, pretty_name, arglist,
6145 TREE_TYPE (TREE_TYPE (instance_ptr)));
6149 print_z_candidates (candidates);
6151 call = error_mark_node;
6155 cand = tourney (candidates);
6162 if (complain & tf_error)
6164 pretty_name = name_as_c_string (name, basetype, &free_p);
6165 arglist = build_tree_list_vec (user_args);
6166 if (skip_first_for_error)
6167 arglist = TREE_CHAIN (arglist);
6168 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
6170 print_z_candidates (candidates);
6174 call = error_mark_node;
6180 if (!(flags & LOOKUP_NONVIRTUAL)
6181 && DECL_PURE_VIRTUAL_P (fn)
6182 && instance == current_class_ref
6183 && (DECL_CONSTRUCTOR_P (current_function_decl)
6184 || DECL_DESTRUCTOR_P (current_function_decl))
6185 && (complain & tf_warning))
6186 /* This is not an error, it is runtime undefined
6188 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
6189 "abstract virtual %q#D called from constructor"
6190 : "abstract virtual %q#D called from destructor"),
6193 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
6194 && is_dummy_object (instance_ptr))
6196 if (complain & tf_error)
6197 error ("cannot call member function %qD without object",
6199 call = error_mark_node;
6203 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
6204 && resolves_to_fixed_type_p (instance, 0))
6205 flags |= LOOKUP_NONVIRTUAL;
6206 /* Now we know what function is being called. */
6209 /* Build the actual CALL_EXPR. */
6210 call = build_over_call (cand, flags, complain);
6211 /* In an expression of the form `a->f()' where `f' turns
6212 out to be a static member function, `a' is
6213 none-the-less evaluated. */
6214 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
6215 && !is_dummy_object (instance_ptr)
6216 && TREE_SIDE_EFFECTS (instance_ptr))
6217 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
6218 instance_ptr, call);
6219 else if (call != error_mark_node
6220 && DECL_DESTRUCTOR_P (cand->fn)
6221 && !VOID_TYPE_P (TREE_TYPE (call)))
6222 /* An explicit call of the form "x->~X()" has type
6223 "void". However, on platforms where destructors
6224 return "this" (i.e., those where
6225 targetm.cxx.cdtor_returns_this is true), such calls
6226 will appear to have a return value of pointer type
6227 to the low-level call machinery. We do not want to
6228 change the low-level machinery, since we want to be
6229 able to optimize "delete f()" on such platforms as
6230 "operator delete(~X(f()))" (rather than generating
6231 "t = f(), ~X(t), operator delete (t)"). */
6232 call = build_nop (void_type_node, call);
6237 if (processing_template_decl && call != error_mark_node)
6239 bool cast_to_void = false;
6241 if (TREE_CODE (call) == COMPOUND_EXPR)
6242 call = TREE_OPERAND (call, 1);
6243 else if (TREE_CODE (call) == NOP_EXPR)
6245 cast_to_void = true;
6246 call = TREE_OPERAND (call, 0);
6248 if (TREE_CODE (call) == INDIRECT_REF)
6249 call = TREE_OPERAND (call, 0);
6250 call = (build_min_non_dep_call_vec
6252 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
6253 orig_instance, orig_fns, NULL_TREE),
6255 call = convert_from_reference (call);
6257 call = build_nop (void_type_node, call);
6260 /* Free all the conversions we allocated. */
6261 obstack_free (&conversion_obstack, p);
6263 if (orig_args != NULL)
6264 release_tree_vector (orig_args);
6269 /* Returns true iff standard conversion sequence ICS1 is a proper
6270 subsequence of ICS2. */
6273 is_subseq (conversion *ics1, conversion *ics2)
6275 /* We can assume that a conversion of the same code
6276 between the same types indicates a subsequence since we only get
6277 here if the types we are converting from are the same. */
6279 while (ics1->kind == ck_rvalue
6280 || ics1->kind == ck_lvalue)
6281 ics1 = ics1->u.next;
6285 while (ics2->kind == ck_rvalue
6286 || ics2->kind == ck_lvalue)
6287 ics2 = ics2->u.next;
6289 if (ics2->kind == ck_user
6290 || ics2->kind == ck_ambig
6291 || ics2->kind == ck_identity)
6292 /* At this point, ICS1 cannot be a proper subsequence of
6293 ICS2. We can get a USER_CONV when we are comparing the
6294 second standard conversion sequence of two user conversion
6298 ics2 = ics2->u.next;
6300 if (ics2->kind == ics1->kind
6301 && same_type_p (ics2->type, ics1->type)
6302 && same_type_p (ics2->u.next->type,
6303 ics1->u.next->type))
6308 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6309 be any _TYPE nodes. */
6312 is_properly_derived_from (tree derived, tree base)
6314 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
6317 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6318 considers every class derived from itself. */
6319 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
6320 && DERIVED_FROM_P (base, derived));
6323 /* We build the ICS for an implicit object parameter as a pointer
6324 conversion sequence. However, such a sequence should be compared
6325 as if it were a reference conversion sequence. If ICS is the
6326 implicit conversion sequence for an implicit object parameter,
6327 modify it accordingly. */
6330 maybe_handle_implicit_object (conversion **ics)
6334 /* [over.match.funcs]
6336 For non-static member functions, the type of the
6337 implicit object parameter is "reference to cv X"
6338 where X is the class of which the function is a
6339 member and cv is the cv-qualification on the member
6340 function declaration. */
6341 conversion *t = *ics;
6342 tree reference_type;
6344 /* The `this' parameter is a pointer to a class type. Make the
6345 implicit conversion talk about a reference to that same class
6347 reference_type = TREE_TYPE (t->type);
6348 reference_type = build_reference_type (reference_type);
6350 if (t->kind == ck_qual)
6352 if (t->kind == ck_ptr)
6354 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
6355 t = direct_reference_binding (reference_type, t);
6357 t->rvaluedness_matches_p = 0;
6362 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6363 and return the initial reference binding conversion. Otherwise,
6364 leave *ICS unchanged and return NULL. */
6367 maybe_handle_ref_bind (conversion **ics)
6369 if ((*ics)->kind == ck_ref_bind)
6371 conversion *old_ics = *ics;
6372 *ics = old_ics->u.next;
6373 (*ics)->user_conv_p = old_ics->user_conv_p;
6374 (*ics)->bad_p = old_ics->bad_p;
6381 /* Compare two implicit conversion sequences according to the rules set out in
6382 [over.ics.rank]. Return values:
6384 1: ics1 is better than ics2
6385 -1: ics2 is better than ics1
6386 0: ics1 and ics2 are indistinguishable */
6389 compare_ics (conversion *ics1, conversion *ics2)
6395 tree deref_from_type1 = NULL_TREE;
6396 tree deref_from_type2 = NULL_TREE;
6397 tree deref_to_type1 = NULL_TREE;
6398 tree deref_to_type2 = NULL_TREE;
6399 conversion_rank rank1, rank2;
6401 /* REF_BINDING is nonzero if the result of the conversion sequence
6402 is a reference type. In that case REF_CONV is the reference
6403 binding conversion. */
6404 conversion *ref_conv1;
6405 conversion *ref_conv2;
6407 /* Handle implicit object parameters. */
6408 maybe_handle_implicit_object (&ics1);
6409 maybe_handle_implicit_object (&ics2);
6411 /* Handle reference parameters. */
6412 ref_conv1 = maybe_handle_ref_bind (&ics1);
6413 ref_conv2 = maybe_handle_ref_bind (&ics2);
6417 When comparing the basic forms of implicit conversion sequences (as
6418 defined in _over.best.ics_)
6420 --a standard conversion sequence (_over.ics.scs_) is a better
6421 conversion sequence than a user-defined conversion sequence
6422 or an ellipsis conversion sequence, and
6424 --a user-defined conversion sequence (_over.ics.user_) is a
6425 better conversion sequence than an ellipsis conversion sequence
6426 (_over.ics.ellipsis_). */
6427 rank1 = CONVERSION_RANK (ics1);
6428 rank2 = CONVERSION_RANK (ics2);
6432 else if (rank1 < rank2)
6435 if (rank1 == cr_bad)
6437 /* XXX Isn't this an extension? */
6438 /* Both ICS are bad. We try to make a decision based on what
6439 would have happened if they'd been good. */
6440 if (ics1->user_conv_p > ics2->user_conv_p
6441 || ics1->rank > ics2->rank)
6443 else if (ics1->user_conv_p < ics2->user_conv_p
6444 || ics1->rank < ics2->rank)
6447 /* We couldn't make up our minds; try to figure it out below. */
6450 if (ics1->ellipsis_p)
6451 /* Both conversions are ellipsis conversions. */
6454 /* User-defined conversion sequence U1 is a better conversion sequence
6455 than another user-defined conversion sequence U2 if they contain the
6456 same user-defined conversion operator or constructor and if the sec-
6457 ond standard conversion sequence of U1 is better than the second
6458 standard conversion sequence of U2. */
6460 if (ics1->user_conv_p)
6465 for (t1 = ics1; t1->kind != ck_user && t1->kind != ck_list; t1 = t1->u.next)
6466 if (t1->kind == ck_ambig || t1->kind == ck_aggr)
6468 for (t2 = ics2; t2->kind != ck_user && t2->kind != ck_list; t2 = t2->u.next)
6469 if (t2->kind == ck_ambig || t2->kind == ck_aggr)
6472 /* Conversion to std::initializer_list is better than other
6473 user-defined conversions. */
6474 if (t1->kind == ck_list
6475 || t2->kind == ck_list)
6477 if (t2->kind != ck_list)
6479 else if (t1->kind != ck_list)
6485 if (t1->cand->fn != t2->cand->fn)
6488 /* We can just fall through here, after setting up
6489 FROM_TYPE1 and FROM_TYPE2. */
6490 from_type1 = t1->type;
6491 from_type2 = t2->type;
6498 /* We're dealing with two standard conversion sequences.
6502 Standard conversion sequence S1 is a better conversion
6503 sequence than standard conversion sequence S2 if
6505 --S1 is a proper subsequence of S2 (comparing the conversion
6506 sequences in the canonical form defined by _over.ics.scs_,
6507 excluding any Lvalue Transformation; the identity
6508 conversion sequence is considered to be a subsequence of
6509 any non-identity conversion sequence */
6512 while (t1->kind != ck_identity)
6514 from_type1 = t1->type;
6517 while (t2->kind != ck_identity)
6519 from_type2 = t2->type;
6522 /* One sequence can only be a subsequence of the other if they start with
6523 the same type. They can start with different types when comparing the
6524 second standard conversion sequence in two user-defined conversion
6526 if (same_type_p (from_type1, from_type2))
6528 if (is_subseq (ics1, ics2))
6530 if (is_subseq (ics2, ics1))
6538 --the rank of S1 is better than the rank of S2 (by the rules
6541 Standard conversion sequences are ordered by their ranks: an Exact
6542 Match is a better conversion than a Promotion, which is a better
6543 conversion than a Conversion.
6545 Two conversion sequences with the same rank are indistinguishable
6546 unless one of the following rules applies:
6548 --A conversion that is not a conversion of a pointer, or pointer
6549 to member, to bool is better than another conversion that is such
6552 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6553 so that we do not have to check it explicitly. */
6554 if (ics1->rank < ics2->rank)
6556 else if (ics2->rank < ics1->rank)
6559 to_type1 = ics1->type;
6560 to_type2 = ics2->type;
6562 /* A conversion from scalar arithmetic type to complex is worse than a
6563 conversion between scalar arithmetic types. */
6564 if (same_type_p (from_type1, from_type2)
6565 && ARITHMETIC_TYPE_P (from_type1)
6566 && ARITHMETIC_TYPE_P (to_type1)
6567 && ARITHMETIC_TYPE_P (to_type2)
6568 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
6569 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
6571 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
6577 if (TYPE_PTR_P (from_type1)
6578 && TYPE_PTR_P (from_type2)
6579 && TYPE_PTR_P (to_type1)
6580 && TYPE_PTR_P (to_type2))
6582 deref_from_type1 = TREE_TYPE (from_type1);
6583 deref_from_type2 = TREE_TYPE (from_type2);
6584 deref_to_type1 = TREE_TYPE (to_type1);
6585 deref_to_type2 = TREE_TYPE (to_type2);
6587 /* The rules for pointers to members A::* are just like the rules
6588 for pointers A*, except opposite: if B is derived from A then
6589 A::* converts to B::*, not vice versa. For that reason, we
6590 switch the from_ and to_ variables here. */
6591 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
6592 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
6593 || (TYPE_PTRMEMFUNC_P (from_type1)
6594 && TYPE_PTRMEMFUNC_P (from_type2)
6595 && TYPE_PTRMEMFUNC_P (to_type1)
6596 && TYPE_PTRMEMFUNC_P (to_type2)))
6598 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
6599 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
6600 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
6601 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
6604 if (deref_from_type1 != NULL_TREE
6605 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
6606 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
6608 /* This was one of the pointer or pointer-like conversions.
6612 --If class B is derived directly or indirectly from class A,
6613 conversion of B* to A* is better than conversion of B* to
6614 void*, and conversion of A* to void* is better than
6615 conversion of B* to void*. */
6616 if (TREE_CODE (deref_to_type1) == VOID_TYPE
6617 && TREE_CODE (deref_to_type2) == VOID_TYPE)
6619 if (is_properly_derived_from (deref_from_type1,
6622 else if (is_properly_derived_from (deref_from_type2,
6626 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
6627 || TREE_CODE (deref_to_type2) == VOID_TYPE)
6629 if (same_type_p (deref_from_type1, deref_from_type2))
6631 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
6633 if (is_properly_derived_from (deref_from_type1,
6637 /* We know that DEREF_TO_TYPE1 is `void' here. */
6638 else if (is_properly_derived_from (deref_from_type1,
6643 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
6644 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
6648 --If class B is derived directly or indirectly from class A
6649 and class C is derived directly or indirectly from B,
6651 --conversion of C* to B* is better than conversion of C* to
6654 --conversion of B* to A* is better than conversion of C* to
6656 if (same_type_p (deref_from_type1, deref_from_type2))
6658 if (is_properly_derived_from (deref_to_type1,
6661 else if (is_properly_derived_from (deref_to_type2,
6665 else if (same_type_p (deref_to_type1, deref_to_type2))
6667 if (is_properly_derived_from (deref_from_type2,
6670 else if (is_properly_derived_from (deref_from_type1,
6676 else if (CLASS_TYPE_P (non_reference (from_type1))
6677 && same_type_p (from_type1, from_type2))
6679 tree from = non_reference (from_type1);
6683 --binding of an expression of type C to a reference of type
6684 B& is better than binding an expression of type C to a
6685 reference of type A&
6687 --conversion of C to B is better than conversion of C to A, */
6688 if (is_properly_derived_from (from, to_type1)
6689 && is_properly_derived_from (from, to_type2))
6691 if (is_properly_derived_from (to_type1, to_type2))
6693 else if (is_properly_derived_from (to_type2, to_type1))
6697 else if (CLASS_TYPE_P (non_reference (to_type1))
6698 && same_type_p (to_type1, to_type2))
6700 tree to = non_reference (to_type1);
6704 --binding of an expression of type B to a reference of type
6705 A& is better than binding an expression of type C to a
6706 reference of type A&,
6708 --conversion of B to A is better than conversion of C to A */
6709 if (is_properly_derived_from (from_type1, to)
6710 && is_properly_derived_from (from_type2, to))
6712 if (is_properly_derived_from (from_type2, from_type1))
6714 else if (is_properly_derived_from (from_type1, from_type2))
6721 --S1 and S2 differ only in their qualification conversion and yield
6722 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6723 qualification signature of type T1 is a proper subset of the cv-
6724 qualification signature of type T2 */
6725 if (ics1->kind == ck_qual
6726 && ics2->kind == ck_qual
6727 && same_type_p (from_type1, from_type2))
6729 int result = comp_cv_qual_signature (to_type1, to_type2);
6736 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6737 to an implicit object parameter, and either S1 binds an lvalue reference
6738 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6739 reference to an rvalue and S2 binds an lvalue reference
6740 (C++0x draft standard, 13.3.3.2)
6742 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6743 types to which the references refer are the same type except for
6744 top-level cv-qualifiers, and the type to which the reference
6745 initialized by S2 refers is more cv-qualified than the type to
6746 which the reference initialized by S1 refers */
6748 if (ref_conv1 && ref_conv2)
6750 if (!ref_conv1->this_p && !ref_conv2->this_p
6751 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
6752 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
6754 if (ref_conv1->rvaluedness_matches_p)
6756 if (ref_conv2->rvaluedness_matches_p)
6760 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6761 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6762 TREE_TYPE (ref_conv1->type));
6765 /* Neither conversion sequence is better than the other. */
6769 /* The source type for this standard conversion sequence. */
6772 source_type (conversion *t)
6774 for (;; t = t->u.next)
6776 if (t->kind == ck_user
6777 || t->kind == ck_ambig
6778 || t->kind == ck_identity)
6784 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6785 a pointer to LOSER and re-running joust to produce the warning if WINNER
6786 is actually used. */
6789 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6791 candidate_warning *cw = (candidate_warning *)
6792 conversion_obstack_alloc (sizeof (candidate_warning));
6794 cw->next = winner->warnings;
6795 winner->warnings = cw;
6798 /* Compare two candidates for overloading as described in
6799 [over.match.best]. Return values:
6801 1: cand1 is better than cand2
6802 -1: cand2 is better than cand1
6803 0: cand1 and cand2 are indistinguishable */
6806 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6809 int off1 = 0, off2 = 0;
6813 /* Candidates that involve bad conversions are always worse than those
6815 if (cand1->viable > cand2->viable)
6817 if (cand1->viable < cand2->viable)
6820 /* If we have two pseudo-candidates for conversions to the same type,
6821 or two candidates for the same function, arbitrarily pick one. */
6822 if (cand1->fn == cand2->fn
6823 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6826 /* a viable function F1
6827 is defined to be a better function than another viable function F2 if
6828 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6829 ICSi(F2), and then */
6831 /* for some argument j, ICSj(F1) is a better conversion sequence than
6834 /* For comparing static and non-static member functions, we ignore
6835 the implicit object parameter of the non-static function. The
6836 standard says to pretend that the static function has an object
6837 parm, but that won't work with operator overloading. */
6838 len = cand1->num_convs;
6839 if (len != cand2->num_convs)
6841 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6842 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6844 gcc_assert (static_1 != static_2);
6855 for (i = 0; i < len; ++i)
6857 conversion *t1 = cand1->convs[i + off1];
6858 conversion *t2 = cand2->convs[i + off2];
6859 int comp = compare_ics (t1, t2);
6864 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6865 == cr_std + cr_promotion)
6866 && t1->kind == ck_std
6867 && t2->kind == ck_std
6868 && TREE_CODE (t1->type) == INTEGER_TYPE
6869 && TREE_CODE (t2->type) == INTEGER_TYPE
6870 && (TYPE_PRECISION (t1->type)
6871 == TYPE_PRECISION (t2->type))
6872 && (TYPE_UNSIGNED (t1->u.next->type)
6873 || (TREE_CODE (t1->u.next->type)
6876 tree type = t1->u.next->type;
6878 struct z_candidate *w, *l;
6880 type1 = t1->type, type2 = t2->type,
6881 w = cand1, l = cand2;
6883 type1 = t2->type, type2 = t1->type,
6884 w = cand2, l = cand1;
6888 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
6889 type, type1, type2);
6890 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
6896 if (winner && comp != winner)
6905 /* warn about confusing overload resolution for user-defined conversions,
6906 either between a constructor and a conversion op, or between two
6908 if (winner && warn_conversion && cand1->second_conv
6909 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6910 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6912 struct z_candidate *w, *l;
6913 bool give_warning = false;
6916 w = cand1, l = cand2;
6918 w = cand2, l = cand1;
6920 /* We don't want to complain about `X::operator T1 ()'
6921 beating `X::operator T2 () const', when T2 is a no less
6922 cv-qualified version of T1. */
6923 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6924 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6926 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6927 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6929 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6934 if (!comp_ptr_ttypes (t, f))
6935 give_warning = true;
6938 give_warning = true;
6944 tree source = source_type (w->convs[0]);
6945 if (! DECL_CONSTRUCTOR_P (w->fn))
6946 source = TREE_TYPE (source);
6947 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
6948 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
6949 source, w->second_conv->type))
6951 inform (input_location, " because conversion sequence for the argument is better");
6962 F1 is a non-template function and F2 is a template function
6965 if (!cand1->template_decl && cand2->template_decl)
6967 else if (cand1->template_decl && !cand2->template_decl)
6971 F1 and F2 are template functions and the function template for F1 is
6972 more specialized than the template for F2 according to the partial
6975 if (cand1->template_decl && cand2->template_decl)
6977 winner = more_specialized_fn
6978 (TI_TEMPLATE (cand1->template_decl),
6979 TI_TEMPLATE (cand2->template_decl),
6980 /* [temp.func.order]: The presence of unused ellipsis and default
6981 arguments has no effect on the partial ordering of function
6982 templates. add_function_candidate() will not have
6983 counted the "this" argument for constructors. */
6984 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6990 the context is an initialization by user-defined conversion (see
6991 _dcl.init_ and _over.match.user_) and the standard conversion
6992 sequence from the return type of F1 to the destination type (i.e.,
6993 the type of the entity being initialized) is a better conversion
6994 sequence than the standard conversion sequence from the return type
6995 of F2 to the destination type. */
6997 if (cand1->second_conv)
6999 winner = compare_ics (cand1->second_conv, cand2->second_conv);
7004 /* Check whether we can discard a builtin candidate, either because we
7005 have two identical ones or matching builtin and non-builtin candidates.
7007 (Pedantically in the latter case the builtin which matched the user
7008 function should not be added to the overload set, but we spot it here.
7011 ... the builtin candidates include ...
7012 - do not have the same parameter type list as any non-template
7013 non-member candidate. */
7015 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
7016 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
7018 for (i = 0; i < len; ++i)
7019 if (!same_type_p (cand1->convs[i]->type,
7020 cand2->convs[i]->type))
7022 if (i == cand1->num_convs)
7024 if (cand1->fn == cand2->fn)
7025 /* Two built-in candidates; arbitrarily pick one. */
7027 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
7028 /* cand1 is built-in; prefer cand2. */
7031 /* cand2 is built-in; prefer cand1. */
7036 /* If the two function declarations represent the same function (this can
7037 happen with declarations in multiple scopes and arg-dependent lookup),
7038 arbitrarily choose one. But first make sure the default args we're
7040 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
7041 && equal_functions (cand1->fn, cand2->fn))
7043 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
7044 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
7046 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
7048 for (i = 0; i < len; ++i)
7050 /* Don't crash if the fn is variadic. */
7053 parms1 = TREE_CHAIN (parms1);
7054 parms2 = TREE_CHAIN (parms2);
7058 parms1 = TREE_CHAIN (parms1);
7060 parms2 = TREE_CHAIN (parms2);
7064 if (!cp_tree_equal (TREE_PURPOSE (parms1),
7065 TREE_PURPOSE (parms2)))
7069 permerror (input_location, "default argument mismatch in "
7070 "overload resolution");
7071 inform (input_location,
7072 " candidate 1: %q+#F", cand1->fn);
7073 inform (input_location,
7074 " candidate 2: %q+#F", cand2->fn);
7077 add_warning (cand1, cand2);
7080 parms1 = TREE_CHAIN (parms1);
7081 parms2 = TREE_CHAIN (parms2);
7089 /* Extension: If the worst conversion for one candidate is worse than the
7090 worst conversion for the other, take the first. */
7093 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
7094 struct z_candidate *w = 0, *l = 0;
7096 for (i = 0; i < len; ++i)
7098 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
7099 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
7100 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
7101 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
7104 winner = 1, w = cand1, l = cand2;
7106 winner = -1, w = cand2, l = cand1;
7111 pedwarn (input_location, 0,
7112 "ISO C++ says that these are ambiguous, even "
7113 "though the worst conversion for the first is better than "
7114 "the worst conversion for the second:");
7115 print_z_candidate (_("candidate 1:"), w);
7116 print_z_candidate (_("candidate 2:"), l);
7124 gcc_assert (!winner);
7128 /* Given a list of candidates for overloading, find the best one, if any.
7129 This algorithm has a worst case of O(2n) (winner is last), and a best
7130 case of O(n/2) (totally ambiguous); much better than a sorting
7133 static struct z_candidate *
7134 tourney (struct z_candidate *candidates)
7136 struct z_candidate *champ = candidates, *challenger;
7138 int champ_compared_to_predecessor = 0;
7140 /* Walk through the list once, comparing each current champ to the next
7141 candidate, knocking out a candidate or two with each comparison. */
7143 for (challenger = champ->next; challenger; )
7145 fate = joust (champ, challenger, 0);
7147 challenger = challenger->next;
7152 champ = challenger->next;
7155 champ_compared_to_predecessor = 0;
7160 champ_compared_to_predecessor = 1;
7163 challenger = champ->next;
7167 /* Make sure the champ is better than all the candidates it hasn't yet
7168 been compared to. */
7170 for (challenger = candidates;
7172 && !(champ_compared_to_predecessor && challenger->next == champ);
7173 challenger = challenger->next)
7175 fate = joust (champ, challenger, 0);
7183 /* Returns nonzero if things of type FROM can be converted to TO. */
7186 can_convert (tree to, tree from)
7188 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
7191 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7194 can_convert_arg (tree to, tree from, tree arg, int flags)
7200 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7201 p = conversion_obstack_alloc (0);
7203 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7205 ok_p = (t && !t->bad_p);
7207 /* Free all the conversions we allocated. */
7208 obstack_free (&conversion_obstack, p);
7213 /* Like can_convert_arg, but allows dubious conversions as well. */
7216 can_convert_arg_bad (tree to, tree from, tree arg)
7221 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7222 p = conversion_obstack_alloc (0);
7223 /* Try to perform the conversion. */
7224 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
7226 /* Free all the conversions we allocated. */
7227 obstack_free (&conversion_obstack, p);
7232 /* Convert EXPR to TYPE. Return the converted expression.
7234 Note that we allow bad conversions here because by the time we get to
7235 this point we are committed to doing the conversion. If we end up
7236 doing a bad conversion, convert_like will complain. */
7239 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
7244 if (error_operand_p (expr))
7245 return error_mark_node;
7247 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7248 p = conversion_obstack_alloc (0);
7250 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7256 if (complain & tf_error)
7258 /* If expr has unknown type, then it is an overloaded function.
7259 Call instantiate_type to get good error messages. */
7260 if (TREE_TYPE (expr) == unknown_type_node)
7261 instantiate_type (type, expr, complain);
7262 else if (invalid_nonstatic_memfn_p (expr, complain))
7263 /* We gave an error. */;
7265 error ("could not convert %qE to %qT", expr, type);
7267 expr = error_mark_node;
7269 else if (processing_template_decl)
7271 /* In a template, we are only concerned about determining the
7272 type of non-dependent expressions, so we do not have to
7273 perform the actual conversion. */
7274 if (TREE_TYPE (expr) != type)
7275 expr = build_nop (type, expr);
7278 expr = convert_like (conv, expr, complain);
7280 /* Free all the conversions we allocated. */
7281 obstack_free (&conversion_obstack, p);
7287 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
7289 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
7292 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7293 permitted. If the conversion is valid, the converted expression is
7294 returned. Otherwise, NULL_TREE is returned, except in the case
7295 that TYPE is a class type; in that case, an error is issued. If
7296 C_CAST_P is true, then this direction initialization is taking
7297 place as part of a static_cast being attempted as part of a C-style
7301 perform_direct_initialization_if_possible (tree type,
7304 tsubst_flags_t complain)
7309 if (type == error_mark_node || error_operand_p (expr))
7310 return error_mark_node;
7313 If the destination type is a (possibly cv-qualified) class type:
7315 -- If the initialization is direct-initialization ...,
7316 constructors are considered. ... If no constructor applies, or
7317 the overload resolution is ambiguous, the initialization is
7319 if (CLASS_TYPE_P (type))
7321 VEC(tree,gc) *args = make_tree_vector_single (expr);
7322 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7323 &args, type, LOOKUP_NORMAL, complain);
7324 release_tree_vector (args);
7325 return build_cplus_new (type, expr);
7328 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7329 p = conversion_obstack_alloc (0);
7331 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
7334 if (!conv || conv->bad_p)
7337 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
7338 /*issue_conversion_warnings=*/false,
7340 tf_warning_or_error);
7342 /* Free all the conversions we allocated. */
7343 obstack_free (&conversion_obstack, p);
7348 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7349 is being bound to a temporary. Create and return a new VAR_DECL
7350 with the indicated TYPE; this variable will store the value to
7351 which the reference is bound. */
7354 make_temporary_var_for_ref_to_temp (tree decl, tree type)
7358 /* Create the variable. */
7359 var = create_temporary_var (type);
7361 /* Register the variable. */
7362 if (TREE_STATIC (decl))
7364 /* Namespace-scope or local static; give it a mangled name. */
7367 TREE_STATIC (var) = 1;
7368 name = mangle_ref_init_variable (decl);
7369 DECL_NAME (var) = name;
7370 SET_DECL_ASSEMBLER_NAME (var, name);
7371 var = pushdecl_top_level (var);
7374 /* Create a new cleanup level if necessary. */
7375 maybe_push_cleanup_level (type);
7380 /* EXPR is the initializer for a variable DECL of reference or
7381 std::initializer_list type. Create, push and return a new VAR_DECL
7382 for the initializer so that it will live as long as DECL. Any
7383 cleanup for the new variable is returned through CLEANUP, and the
7384 code to initialize the new variable is returned through INITP. */
7387 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
7393 /* Create the temporary variable. */
7394 type = TREE_TYPE (expr);
7395 var = make_temporary_var_for_ref_to_temp (decl, type);
7396 layout_decl (var, 0);
7397 /* If the rvalue is the result of a function call it will be
7398 a TARGET_EXPR. If it is some other construct (such as a
7399 member access expression where the underlying object is
7400 itself the result of a function call), turn it into a
7401 TARGET_EXPR here. It is important that EXPR be a
7402 TARGET_EXPR below since otherwise the INIT_EXPR will
7403 attempt to make a bitwise copy of EXPR to initialize
7405 if (TREE_CODE (expr) != TARGET_EXPR)
7406 expr = get_target_expr (expr);
7407 /* Create the INIT_EXPR that will initialize the temporary
7409 init = build2 (INIT_EXPR, type, var, expr);
7410 if (at_function_scope_p ())
7412 add_decl_expr (var);
7414 if (TREE_STATIC (var))
7415 init = add_stmt_to_compound (init, register_dtor_fn (var));
7417 *cleanup = cxx_maybe_build_cleanup (var);
7419 /* We must be careful to destroy the temporary only
7420 after its initialization has taken place. If the
7421 initialization throws an exception, then the
7422 destructor should not be run. We cannot simply
7423 transform INIT into something like:
7425 (INIT, ({ CLEANUP_STMT; }))
7427 because emit_local_var always treats the
7428 initializer as a full-expression. Thus, the
7429 destructor would run too early; it would run at the
7430 end of initializing the reference variable, rather
7431 than at the end of the block enclosing the
7434 The solution is to pass back a cleanup expression
7435 which the caller is responsible for attaching to
7436 the statement tree. */
7440 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
7441 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7442 static_aggregates = tree_cons (NULL_TREE, var,
7450 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7451 initializing a variable of that TYPE. If DECL is non-NULL, it is
7452 the VAR_DECL being initialized with the EXPR. (In that case, the
7453 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7454 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7455 return, if *CLEANUP is no longer NULL, it will be an expression
7456 that should be pushed as a cleanup after the returned expression
7457 is used to initialize DECL.
7459 Return the converted expression. */
7462 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
7467 if (type == error_mark_node || error_operand_p (expr))
7468 return error_mark_node;
7470 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7471 p = conversion_obstack_alloc (0);
7473 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
7475 if (!conv || conv->bad_p)
7477 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
7478 && !real_lvalue_p (expr))
7479 error ("invalid initialization of non-const reference of "
7480 "type %qT from a temporary of type %qT",
7481 type, TREE_TYPE (expr));
7483 error ("invalid initialization of reference of type "
7484 "%qT from expression of type %qT", type,
7486 return error_mark_node;
7489 /* If DECL is non-NULL, then this special rule applies:
7493 The temporary to which the reference is bound or the temporary
7494 that is the complete object to which the reference is bound
7495 persists for the lifetime of the reference.
7497 The temporaries created during the evaluation of the expression
7498 initializing the reference, except the temporary to which the
7499 reference is bound, are destroyed at the end of the
7500 full-expression in which they are created.
7502 In that case, we store the converted expression into a new
7503 VAR_DECL in a new scope.
7505 However, we want to be careful not to create temporaries when
7506 they are not required. For example, given:
7509 struct D : public B {};
7513 there is no need to copy the return value from "f"; we can just
7514 extend its lifetime. Similarly, given:
7517 struct T { operator S(); };
7521 we can extend the lifetime of the return value of the conversion
7523 gcc_assert (conv->kind == ck_ref_bind);
7527 tree base_conv_type;
7529 /* Skip over the REF_BIND. */
7530 conv = conv->u.next;
7531 /* If the next conversion is a BASE_CONV, skip that too -- but
7532 remember that the conversion was required. */
7533 if (conv->kind == ck_base)
7535 base_conv_type = conv->type;
7536 conv = conv->u.next;
7539 base_conv_type = NULL_TREE;
7540 /* Perform the remainder of the conversion. */
7541 expr = convert_like_real (conv, expr,
7542 /*fn=*/NULL_TREE, /*argnum=*/0,
7544 /*issue_conversion_warnings=*/true,
7546 tf_warning_or_error);
7547 if (error_operand_p (expr))
7548 expr = error_mark_node;
7551 if (!real_lvalue_p (expr))
7554 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
7555 /* Use its address to initialize the reference variable. */
7556 expr = build_address (var);
7558 expr = convert_to_base (expr,
7559 build_pointer_type (base_conv_type),
7560 /*check_access=*/true,
7562 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
7565 /* Take the address of EXPR. */
7566 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
7567 /* If a BASE_CONV was required, perform it now. */
7569 expr = (perform_implicit_conversion
7570 (build_pointer_type (base_conv_type), expr,
7571 tf_warning_or_error));
7572 expr = build_nop (type, expr);
7576 /* Perform the conversion. */
7577 expr = convert_like (conv, expr, tf_warning_or_error);
7579 /* Free all the conversions we allocated. */
7580 obstack_free (&conversion_obstack, p);
7585 /* Returns true iff TYPE is some variant of std::initializer_list. */
7588 is_std_init_list (tree type)
7590 return (CLASS_TYPE_P (type)
7591 && CP_TYPE_CONTEXT (type) == std_node
7592 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
7595 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7596 will accept an argument list of a single std::initializer_list<T>. */
7599 is_list_ctor (tree decl)
7601 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
7604 if (!args || args == void_list_node)
7607 arg = non_reference (TREE_VALUE (args));
7608 if (!is_std_init_list (arg))
7611 args = TREE_CHAIN (args);
7613 if (args && args != void_list_node && !TREE_PURPOSE (args))
7614 /* There are more non-defaulted parms. */
7620 #include "gt-cp-call.h"