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,
5 Free Software Foundation, Inc.
6 Contributed by Michael Tiemann (tiemann@cygnus.com) and
7 modified by Brendan Kehoe (brendan@cygnus.com).
9 This file is part of GCC.
11 GCC is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 3, or (at your option)
16 GCC is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
26 /* High-level class interface. */
30 #include "coretypes.h"
37 #include "diagnostic-core.h"
41 #include "langhooks.h"
42 #include "c-family/c-objc.h"
45 /* The various kinds of conversion. */
47 typedef enum conversion_kind {
63 /* The rank of the conversion. Order of the enumerals matters; better
64 conversions should come earlier in the list. */
66 typedef enum conversion_rank {
77 /* An implicit conversion sequence, in the sense of [over.best.ics].
78 The first conversion to be performed is at the end of the chain.
79 That conversion is always a cr_identity conversion. */
81 typedef struct conversion conversion;
83 /* The kind of conversion represented by this step. */
85 /* The rank of this conversion. */
87 BOOL_BITFIELD user_conv_p : 1;
88 BOOL_BITFIELD ellipsis_p : 1;
89 BOOL_BITFIELD this_p : 1;
90 /* True if this conversion would be permitted with a bending of
91 language standards, e.g. disregarding pointer qualifiers or
92 converting integers to pointers. */
93 BOOL_BITFIELD bad_p : 1;
94 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
95 temporary should be created to hold the result of the
97 BOOL_BITFIELD need_temporary_p : 1;
98 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
99 from a pointer-to-derived to pointer-to-base is being performed. */
100 BOOL_BITFIELD base_p : 1;
101 /* If KIND is ck_ref_bind, true when either an lvalue reference is
102 being bound to an lvalue expression or an rvalue reference is
103 being bound to an rvalue expression. If KIND is ck_rvalue,
104 true when we should treat an lvalue as an rvalue (12.8p33). If
105 KIND is ck_base, always false. */
106 BOOL_BITFIELD rvaluedness_matches_p: 1;
107 BOOL_BITFIELD check_narrowing: 1;
108 /* The type of the expression resulting from the conversion. */
111 /* The next conversion in the chain. Since the conversions are
112 arranged from outermost to innermost, the NEXT conversion will
113 actually be performed before this conversion. This variant is
114 used only when KIND is neither ck_identity nor ck_ambig. */
116 /* The expression at the beginning of the conversion chain. This
117 variant is used only if KIND is ck_identity or ck_ambig. */
119 /* The array of conversions for an initializer_list. */
122 /* The function candidate corresponding to this conversion
123 sequence. This field is only used if KIND is ck_user. */
124 struct z_candidate *cand;
127 #define CONVERSION_RANK(NODE) \
128 ((NODE)->bad_p ? cr_bad \
129 : (NODE)->ellipsis_p ? cr_ellipsis \
130 : (NODE)->user_conv_p ? cr_user \
133 #define BAD_CONVERSION_RANK(NODE) \
134 ((NODE)->ellipsis_p ? cr_ellipsis \
135 : (NODE)->user_conv_p ? cr_user \
138 static struct obstack conversion_obstack;
139 static bool conversion_obstack_initialized;
140 struct rejection_reason;
142 static struct z_candidate * tourney (struct z_candidate *);
143 static int equal_functions (tree, tree);
144 static int joust (struct z_candidate *, struct z_candidate *, bool);
145 static int compare_ics (conversion *, conversion *);
146 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
147 static tree build_java_interface_fn_ref (tree, tree);
148 #define convert_like(CONV, EXPR, COMPLAIN) \
149 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
150 /*issue_conversion_warnings=*/true, \
151 /*c_cast_p=*/false, (COMPLAIN))
152 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
153 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
154 /*issue_conversion_warnings=*/true, \
155 /*c_cast_p=*/false, (COMPLAIN))
156 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
157 bool, tsubst_flags_t);
158 static void op_error (enum tree_code, enum tree_code, tree, tree,
160 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
161 static void print_z_candidate (const char *, struct z_candidate *);
162 static void print_z_candidates (location_t, struct z_candidate *);
163 static tree build_this (tree);
164 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
165 static bool any_strictly_viable (struct z_candidate *);
166 static struct z_candidate *add_template_candidate
167 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
168 tree, tree, tree, int, unification_kind_t);
169 static struct z_candidate *add_template_candidate_real
170 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
171 tree, tree, tree, int, tree, unification_kind_t);
172 static struct z_candidate *add_template_conv_candidate
173 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
175 static void add_builtin_candidates
176 (struct z_candidate **, enum tree_code, enum tree_code,
178 static void add_builtin_candidate
179 (struct z_candidate **, enum tree_code, enum tree_code,
180 tree, tree, tree, tree *, tree *, int);
181 static bool is_complete (tree);
182 static void build_builtin_candidate
183 (struct z_candidate **, tree, tree, tree, tree *, tree *,
185 static struct z_candidate *add_conv_candidate
186 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
188 static struct z_candidate *add_function_candidate
189 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
191 static conversion *implicit_conversion (tree, tree, tree, bool, int);
192 static conversion *standard_conversion (tree, tree, tree, bool, int);
193 static conversion *reference_binding (tree, tree, tree, bool, int);
194 static conversion *build_conv (conversion_kind, tree, conversion *);
195 static conversion *build_list_conv (tree, tree, int);
196 static bool is_subseq (conversion *, conversion *);
197 static conversion *maybe_handle_ref_bind (conversion **);
198 static void maybe_handle_implicit_object (conversion **);
199 static struct z_candidate *add_candidate
200 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
201 conversion **, tree, tree, int, struct rejection_reason *);
202 static tree source_type (conversion *);
203 static void add_warning (struct z_candidate *, struct z_candidate *);
204 static bool reference_compatible_p (tree, tree);
205 static conversion *convert_class_to_reference (tree, tree, tree, int);
206 static conversion *direct_reference_binding (tree, conversion *);
207 static bool promoted_arithmetic_type_p (tree);
208 static conversion *conditional_conversion (tree, tree);
209 static char *name_as_c_string (tree, tree, bool *);
210 static tree prep_operand (tree);
211 static void add_candidates (tree, tree, const VEC(tree,gc) *, tree, tree, bool,
212 tree, tree, int, struct z_candidate **);
213 static conversion *merge_conversion_sequences (conversion *, conversion *);
214 static bool magic_varargs_p (tree);
215 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
217 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
218 NAME can take many forms... */
221 check_dtor_name (tree basetype, tree name)
223 /* Just accept something we've already complained about. */
224 if (name == error_mark_node)
227 if (TREE_CODE (name) == TYPE_DECL)
228 name = TREE_TYPE (name);
229 else if (TYPE_P (name))
231 else if (TREE_CODE (name) == IDENTIFIER_NODE)
233 if ((MAYBE_CLASS_TYPE_P (basetype)
234 && name == constructor_name (basetype))
235 || (TREE_CODE (basetype) == ENUMERAL_TYPE
236 && name == TYPE_IDENTIFIER (basetype)))
239 name = get_type_value (name);
245 template <class T> struct S { ~S(); };
249 NAME will be a class template. */
250 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
254 if (!name || name == error_mark_node)
256 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
259 /* We want the address of a function or method. We avoid creating a
260 pointer-to-member function. */
263 build_addr_func (tree function)
265 tree type = TREE_TYPE (function);
267 /* We have to do these by hand to avoid real pointer to member
269 if (TREE_CODE (type) == METHOD_TYPE)
271 if (TREE_CODE (function) == OFFSET_REF)
273 tree object = build_address (TREE_OPERAND (function, 0));
274 return get_member_function_from_ptrfunc (&object,
275 TREE_OPERAND (function, 1));
277 function = build_address (function);
280 function = decay_conversion (function);
285 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
286 POINTER_TYPE to those. Note, pointer to member function types
287 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
288 two variants. build_call_a is the primitive taking an array of
289 arguments, while build_call_n is a wrapper that handles varargs. */
292 build_call_n (tree function, int n, ...)
295 return build_call_a (function, 0, NULL);
298 tree *argarray = XALLOCAVEC (tree, n);
303 for (i = 0; i < n; i++)
304 argarray[i] = va_arg (ap, tree);
306 return build_call_a (function, n, argarray);
311 build_call_a (tree function, int n, tree *argarray)
313 int is_constructor = 0;
320 function = build_addr_func (function);
322 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
323 fntype = TREE_TYPE (TREE_TYPE (function));
324 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
325 || TREE_CODE (fntype) == METHOD_TYPE);
326 result_type = TREE_TYPE (fntype);
327 /* An rvalue has no cv-qualifiers. */
328 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
329 result_type = cv_unqualified (result_type);
331 if (TREE_CODE (function) == ADDR_EXPR
332 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
334 decl = TREE_OPERAND (function, 0);
335 if (!TREE_USED (decl))
337 /* We invoke build_call directly for several library
338 functions. These may have been declared normally if
339 we're building libgcc, so we can't just check
341 gcc_assert (DECL_ARTIFICIAL (decl)
342 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
350 /* We check both the decl and the type; a function may be known not to
351 throw without being declared throw(). */
352 nothrow = ((decl && TREE_NOTHROW (decl))
353 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
355 if (!nothrow && at_function_scope_p () && cfun && cp_function_chain)
356 cp_function_chain->can_throw = 1;
358 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
359 current_function_returns_abnormally = 1;
361 if (decl && TREE_DEPRECATED (decl))
362 warn_deprecated_use (decl, NULL_TREE);
363 require_complete_eh_spec_types (fntype, decl);
365 if (decl && DECL_CONSTRUCTOR_P (decl))
368 /* Don't pass empty class objects by value. This is useful
369 for tags in STL, which are used to control overload resolution.
370 We don't need to handle other cases of copying empty classes. */
371 if (! decl || ! DECL_BUILT_IN (decl))
372 for (i = 0; i < n; i++)
373 if (is_empty_class (TREE_TYPE (argarray[i]))
374 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
376 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
377 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
381 function = build_call_array_loc (input_location,
382 result_type, function, n, argarray);
383 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
384 TREE_NOTHROW (function) = nothrow;
389 /* Build something of the form ptr->method (args)
390 or object.method (args). This can also build
391 calls to constructors, and find friends.
393 Member functions always take their class variable
396 INSTANCE is a class instance.
398 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
400 PARMS help to figure out what that NAME really refers to.
402 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
403 down to the real instance type to use for access checking. We need this
404 information to get protected accesses correct.
406 FLAGS is the logical disjunction of zero or more LOOKUP_
407 flags. See cp-tree.h for more info.
409 If this is all OK, calls build_function_call with the resolved
412 This function must also handle being called to perform
413 initialization, promotion/coercion of arguments, and
414 instantiation of default parameters.
416 Note that NAME may refer to an instance variable name. If
417 `operator()()' is defined for the type of that field, then we return
420 /* New overloading code. */
422 typedef struct z_candidate z_candidate;
424 typedef struct candidate_warning candidate_warning;
425 struct candidate_warning {
427 candidate_warning *next;
430 /* Information for providing diagnostics about why overloading failed. */
432 enum rejection_reason_code {
435 rr_explicit_conversion,
437 rr_bad_arg_conversion,
438 rr_template_unification,
439 rr_template_instantiation,
443 struct conversion_info {
444 /* The index of the argument, 0-based. */
446 /* The type of the actual argument. */
448 /* The type of the formal argument. */
452 struct rejection_reason {
453 enum rejection_reason_code code;
455 /* Information about an arity mismatch. */
457 /* The expected number of arguments. */
459 /* The actual number of arguments in the call. */
461 /* Whether the call was a varargs call. */
464 /* Information about an argument conversion mismatch. */
465 struct conversion_info conversion;
466 /* Same, but for bad argument conversions. */
467 struct conversion_info bad_conversion;
468 /* Information about template unification failures. These are the
469 parameters passed to fn_type_unification. */
477 unification_kind_t strict;
479 } template_unification;
480 /* Information about template instantiation failures. These are the
481 parameters passed to instantiate_template. */
485 } template_instantiation;
490 /* The FUNCTION_DECL that will be called if this candidate is
491 selected by overload resolution. */
493 /* If not NULL_TREE, the first argument to use when calling this
496 /* The rest of the arguments to use when calling this function. If
497 there are no further arguments this may be NULL or it may be an
499 const VEC(tree,gc) *args;
500 /* The implicit conversion sequences for each of the arguments to
503 /* The number of implicit conversion sequences. */
505 /* If FN is a user-defined conversion, the standard conversion
506 sequence from the type returned by FN to the desired destination
508 conversion *second_conv;
510 struct rejection_reason *reason;
511 /* If FN is a member function, the binfo indicating the path used to
512 qualify the name of FN at the call site. This path is used to
513 determine whether or not FN is accessible if it is selected by
514 overload resolution. The DECL_CONTEXT of FN will always be a
515 (possibly improper) base of this binfo. */
517 /* If FN is a non-static member function, the binfo indicating the
518 subobject to which the `this' pointer should be converted if FN
519 is selected by overload resolution. The type pointed to the by
520 the `this' pointer must correspond to the most derived class
521 indicated by the CONVERSION_PATH. */
522 tree conversion_path;
525 candidate_warning *warnings;
529 /* Returns true iff T is a null pointer constant in the sense of
533 null_ptr_cst_p (tree t)
537 A null pointer constant is an integral constant expression
538 (_expr.const_) rvalue of integer type that evaluates to zero or
539 an rvalue of type std::nullptr_t. */
540 if (NULLPTR_TYPE_P (TREE_TYPE (t)))
542 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
544 /* Core issue 903 says only literal 0 is a null pointer constant. */
545 if (cxx_dialect < cxx0x)
547 t = integral_constant_value (t);
550 if (integer_zerop (t) && !TREE_OVERFLOW (t))
556 /* Returns true iff T is a null member pointer value (4.11). */
559 null_member_pointer_value_p (tree t)
561 tree type = TREE_TYPE (t);
564 else if (TYPE_PTRMEMFUNC_P (type))
565 return (TREE_CODE (t) == CONSTRUCTOR
566 && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value));
567 else if (TYPE_PTRMEM_P (type))
568 return integer_all_onesp (t);
573 /* Returns nonzero if PARMLIST consists of only default parms,
574 ellipsis, and/or undeduced parameter packs. */
577 sufficient_parms_p (const_tree parmlist)
579 for (; parmlist && parmlist != void_list_node;
580 parmlist = TREE_CHAIN (parmlist))
581 if (!TREE_PURPOSE (parmlist)
582 && !PACK_EXPANSION_P (TREE_VALUE (parmlist)))
587 /* Allocate N bytes of memory from the conversion obstack. The memory
588 is zeroed before being returned. */
591 conversion_obstack_alloc (size_t n)
594 if (!conversion_obstack_initialized)
596 gcc_obstack_init (&conversion_obstack);
597 conversion_obstack_initialized = true;
599 p = obstack_alloc (&conversion_obstack, n);
604 /* Allocate rejection reasons. */
606 static struct rejection_reason *
607 alloc_rejection (enum rejection_reason_code code)
609 struct rejection_reason *p;
610 p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p);
615 static struct rejection_reason *
616 arity_rejection (tree first_arg, int expected, int actual)
618 struct rejection_reason *r = alloc_rejection (rr_arity);
619 int adjust = first_arg != NULL_TREE;
620 r->u.arity.expected = expected - adjust;
621 r->u.arity.actual = actual - adjust;
625 static struct rejection_reason *
626 arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
628 struct rejection_reason *r = alloc_rejection (rr_arg_conversion);
629 int adjust = first_arg != NULL_TREE;
630 r->u.conversion.n_arg = n_arg - adjust;
631 r->u.conversion.from_type = from;
632 r->u.conversion.to_type = to;
636 static struct rejection_reason *
637 bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
639 struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion);
640 int adjust = first_arg != NULL_TREE;
641 r->u.bad_conversion.n_arg = n_arg - adjust;
642 r->u.bad_conversion.from_type = from;
643 r->u.bad_conversion.to_type = to;
647 static struct rejection_reason *
648 explicit_conversion_rejection (tree from, tree to)
650 struct rejection_reason *r = alloc_rejection (rr_explicit_conversion);
651 r->u.conversion.n_arg = 0;
652 r->u.conversion.from_type = from;
653 r->u.conversion.to_type = to;
657 static struct rejection_reason *
658 template_unification_rejection (tree tmpl, tree explicit_targs, tree targs,
659 const tree *args, unsigned int nargs,
660 tree return_type, unification_kind_t strict,
663 size_t args_n_bytes = sizeof (*args) * nargs;
664 tree *args1 = (tree *) conversion_obstack_alloc (args_n_bytes);
665 struct rejection_reason *r = alloc_rejection (rr_template_unification);
666 r->u.template_unification.tmpl = tmpl;
667 r->u.template_unification.explicit_targs = explicit_targs;
668 r->u.template_unification.targs = targs;
669 /* Copy args to our own storage. */
670 memcpy (args1, args, args_n_bytes);
671 r->u.template_unification.args = args1;
672 r->u.template_unification.nargs = nargs;
673 r->u.template_unification.return_type = return_type;
674 r->u.template_unification.strict = strict;
675 r->u.template_unification.flags = flags;
679 static struct rejection_reason *
680 template_unification_error_rejection (void)
682 return alloc_rejection (rr_template_unification);
685 static struct rejection_reason *
686 template_instantiation_rejection (tree tmpl, tree targs)
688 struct rejection_reason *r = alloc_rejection (rr_template_instantiation);
689 r->u.template_instantiation.tmpl = tmpl;
690 r->u.template_instantiation.targs = targs;
694 static struct rejection_reason *
695 invalid_copy_with_fn_template_rejection (void)
697 struct rejection_reason *r = alloc_rejection (rr_invalid_copy);
701 /* Dynamically allocate a conversion. */
704 alloc_conversion (conversion_kind kind)
707 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
712 #ifdef ENABLE_CHECKING
714 /* Make sure that all memory on the conversion obstack has been
718 validate_conversion_obstack (void)
720 if (conversion_obstack_initialized)
721 gcc_assert ((obstack_next_free (&conversion_obstack)
722 == obstack_base (&conversion_obstack)));
725 #endif /* ENABLE_CHECKING */
727 /* Dynamically allocate an array of N conversions. */
730 alloc_conversions (size_t n)
732 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
736 build_conv (conversion_kind code, tree type, conversion *from)
739 conversion_rank rank = CONVERSION_RANK (from);
741 /* Note that the caller is responsible for filling in t->cand for
742 user-defined conversions. */
743 t = alloc_conversion (code);
766 t->user_conv_p = (code == ck_user || from->user_conv_p);
767 t->bad_p = from->bad_p;
772 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
773 specialization of std::initializer_list<T>, if such a conversion is
777 build_list_conv (tree type, tree ctor, int flags)
779 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
780 unsigned len = CONSTRUCTOR_NELTS (ctor);
781 conversion **subconvs = alloc_conversions (len);
786 /* Within a list-initialization we can have more user-defined
788 flags &= ~LOOKUP_NO_CONVERSION;
789 /* But no narrowing conversions. */
790 flags |= LOOKUP_NO_NARROWING;
792 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
795 = implicit_conversion (elttype, TREE_TYPE (val), val,
803 t = alloc_conversion (ck_list);
805 t->u.list = subconvs;
808 for (i = 0; i < len; ++i)
810 conversion *sub = subconvs[i];
811 if (sub->rank > t->rank)
813 if (sub->user_conv_p)
814 t->user_conv_p = true;
822 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
823 is a valid aggregate initializer for array type ATYPE. */
826 can_convert_array (tree atype, tree ctor, int flags)
829 tree elttype = TREE_TYPE (atype);
830 for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
832 tree val = CONSTRUCTOR_ELT (ctor, i)->value;
834 if (TREE_CODE (elttype) == ARRAY_TYPE
835 && TREE_CODE (val) == CONSTRUCTOR)
836 ok = can_convert_array (elttype, val, flags);
838 ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags);
845 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
846 aggregate class, if such a conversion is possible. */
849 build_aggr_conv (tree type, tree ctor, int flags)
851 unsigned HOST_WIDE_INT i = 0;
853 tree field = next_initializable_field (TYPE_FIELDS (type));
854 tree empty_ctor = NULL_TREE;
856 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
858 tree ftype = TREE_TYPE (field);
862 if (i < CONSTRUCTOR_NELTS (ctor))
863 val = CONSTRUCTOR_ELT (ctor, i)->value;
866 if (empty_ctor == NULL_TREE)
867 empty_ctor = build_constructor (init_list_type_node, NULL);
872 if (TREE_CODE (ftype) == ARRAY_TYPE
873 && TREE_CODE (val) == CONSTRUCTOR)
874 ok = can_convert_array (ftype, val, flags);
876 ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags);
881 if (TREE_CODE (type) == UNION_TYPE)
885 if (i < CONSTRUCTOR_NELTS (ctor))
888 c = alloc_conversion (ck_aggr);
891 c->user_conv_p = true;
896 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
897 array type, if such a conversion is possible. */
900 build_array_conv (tree type, tree ctor, int flags)
903 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
904 tree elttype = TREE_TYPE (type);
909 enum conversion_rank rank = cr_exact;
911 if (TYPE_DOMAIN (type))
913 unsigned HOST_WIDE_INT alen = tree_low_cst (array_type_nelts_top (type), 1);
918 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
921 = implicit_conversion (elttype, TREE_TYPE (val), val,
926 if (sub->rank > rank)
928 if (sub->user_conv_p)
934 c = alloc_conversion (ck_aggr);
937 c->user_conv_p = user;
943 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
944 complex type, if such a conversion is possible. */
947 build_complex_conv (tree type, tree ctor, int flags)
950 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
951 tree elttype = TREE_TYPE (type);
956 enum conversion_rank rank = cr_exact;
961 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
964 = implicit_conversion (elttype, TREE_TYPE (val), val,
969 if (sub->rank > rank)
971 if (sub->user_conv_p)
977 c = alloc_conversion (ck_aggr);
980 c->user_conv_p = user;
986 /* Build a representation of the identity conversion from EXPR to
987 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
990 build_identity_conv (tree type, tree expr)
994 c = alloc_conversion (ck_identity);
1001 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1002 were multiple user-defined conversions to accomplish the job.
1003 Build a conversion that indicates that ambiguity. */
1006 build_ambiguous_conv (tree type, tree expr)
1010 c = alloc_conversion (ck_ambig);
1018 strip_top_quals (tree t)
1020 if (TREE_CODE (t) == ARRAY_TYPE)
1022 return cp_build_qualified_type (t, 0);
1025 /* Returns the standard conversion path (see [conv]) from type FROM to type
1026 TO, if any. For proper handling of null pointer constants, you must
1027 also pass the expression EXPR to convert from. If C_CAST_P is true,
1028 this conversion is coming from a C-style cast. */
1031 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
1034 enum tree_code fcode, tcode;
1036 bool fromref = false;
1039 to = non_reference (to);
1040 if (TREE_CODE (from) == REFERENCE_TYPE)
1043 from = TREE_TYPE (from);
1046 to = strip_top_quals (to);
1047 from = strip_top_quals (from);
1049 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
1050 && expr && type_unknown_p (expr))
1052 tsubst_flags_t tflags = tf_conv;
1053 if (!(flags & LOOKUP_PROTECT))
1054 tflags |= tf_no_access_control;
1055 expr = instantiate_type (to, expr, tflags);
1056 if (expr == error_mark_node)
1058 from = TREE_TYPE (expr);
1061 fcode = TREE_CODE (from);
1062 tcode = TREE_CODE (to);
1064 conv = build_identity_conv (from, expr);
1065 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
1067 from = type_decays_to (from);
1068 fcode = TREE_CODE (from);
1069 conv = build_conv (ck_lvalue, from, conv);
1071 else if (fromref || (expr && lvalue_p (expr)))
1076 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
1079 from = strip_top_quals (bitfield_type);
1080 fcode = TREE_CODE (from);
1083 conv = build_conv (ck_rvalue, from, conv);
1084 if (flags & LOOKUP_PREFER_RVALUE)
1085 conv->rvaluedness_matches_p = true;
1088 /* Allow conversion between `__complex__' data types. */
1089 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
1091 /* The standard conversion sequence to convert FROM to TO is
1092 the standard conversion sequence to perform componentwise
1094 conversion *part_conv = standard_conversion
1095 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
1099 conv = build_conv (part_conv->kind, to, conv);
1100 conv->rank = part_conv->rank;
1108 if (same_type_p (from, to))
1110 if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue)
1111 conv->type = qualified_to;
1116 A null pointer constant can be converted to a pointer type; ... A
1117 null pointer constant of integral type can be converted to an
1118 rvalue of type std::nullptr_t. */
1119 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to)
1120 || NULLPTR_TYPE_P (to))
1121 && expr && null_ptr_cst_p (expr))
1122 conv = build_conv (ck_std, to, conv);
1123 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
1124 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
1126 /* For backwards brain damage compatibility, allow interconversion of
1127 pointers and integers with a pedwarn. */
1128 conv = build_conv (ck_std, to, conv);
1131 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
1133 /* For backwards brain damage compatibility, allow interconversion of
1134 enums and integers with a pedwarn. */
1135 conv = build_conv (ck_std, to, conv);
1138 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
1139 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
1144 if (tcode == POINTER_TYPE
1145 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
1148 else if (VOID_TYPE_P (TREE_TYPE (to))
1149 && !TYPE_PTRMEM_P (from)
1150 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
1152 tree nfrom = TREE_TYPE (from);
1153 from = build_pointer_type
1154 (cp_build_qualified_type (void_type_node,
1155 cp_type_quals (nfrom)));
1156 conv = build_conv (ck_ptr, from, conv);
1158 else if (TYPE_PTRMEM_P (from))
1160 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
1161 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
1163 if (DERIVED_FROM_P (fbase, tbase)
1164 && (same_type_ignoring_top_level_qualifiers_p
1165 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
1166 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
1168 from = build_ptrmem_type (tbase,
1169 TYPE_PTRMEM_POINTED_TO_TYPE (from));
1170 conv = build_conv (ck_pmem, from, conv);
1172 else if (!same_type_p (fbase, tbase))
1175 else if (CLASS_TYPE_P (TREE_TYPE (from))
1176 && CLASS_TYPE_P (TREE_TYPE (to))
1179 An rvalue of type "pointer to cv D," where D is a
1180 class type, can be converted to an rvalue of type
1181 "pointer to cv B," where B is a base class (clause
1182 _class.derived_) of D. If B is an inaccessible
1183 (clause _class.access_) or ambiguous
1184 (_class.member.lookup_) base class of D, a program
1185 that necessitates this conversion is ill-formed.
1186 Therefore, we use DERIVED_FROM_P, and do not check
1187 access or uniqueness. */
1188 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
1191 cp_build_qualified_type (TREE_TYPE (to),
1192 cp_type_quals (TREE_TYPE (from)));
1193 from = build_pointer_type (from);
1194 conv = build_conv (ck_ptr, from, conv);
1195 conv->base_p = true;
1198 if (tcode == POINTER_TYPE)
1200 to_pointee = TREE_TYPE (to);
1201 from_pointee = TREE_TYPE (from);
1205 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
1206 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
1209 if (same_type_p (from, to))
1211 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
1212 /* In a C-style cast, we ignore CV-qualification because we
1213 are allowed to perform a static_cast followed by a
1215 conv = build_conv (ck_qual, to, conv);
1216 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
1217 conv = build_conv (ck_qual, to, conv);
1218 else if (expr && string_conv_p (to, expr, 0))
1219 /* converting from string constant to char *. */
1220 conv = build_conv (ck_qual, to, conv);
1221 /* Allow conversions among compatible ObjC pointer types (base
1222 conversions have been already handled above). */
1223 else if (c_dialect_objc ()
1224 && objc_compare_types (to, from, -4, NULL_TREE))
1225 conv = build_conv (ck_ptr, to, conv);
1226 else if (ptr_reasonably_similar (to_pointee, from_pointee))
1228 conv = build_conv (ck_ptr, to, conv);
1236 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
1238 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
1239 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
1240 tree fbase = class_of_this_parm (fromfn);
1241 tree tbase = class_of_this_parm (tofn);
1243 if (!DERIVED_FROM_P (fbase, tbase)
1244 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
1245 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
1246 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
1247 || cp_type_quals (fbase) != cp_type_quals (tbase))
1250 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
1251 from = build_ptrmemfunc_type (build_pointer_type (from));
1252 conv = build_conv (ck_pmem, from, conv);
1253 conv->base_p = true;
1255 else if (tcode == BOOLEAN_TYPE)
1259 An rvalue of arithmetic, unscoped enumeration, pointer, or
1260 pointer to member type can be converted to an rvalue of type
1261 bool. ... An rvalue of type std::nullptr_t can be converted
1262 to an rvalue of type bool; */
1263 if (ARITHMETIC_TYPE_P (from)
1264 || UNSCOPED_ENUM_P (from)
1265 || fcode == POINTER_TYPE
1266 || TYPE_PTR_TO_MEMBER_P (from)
1267 || NULLPTR_TYPE_P (from))
1269 conv = build_conv (ck_std, to, conv);
1270 if (fcode == POINTER_TYPE
1271 || TYPE_PTRMEM_P (from)
1272 || (TYPE_PTRMEMFUNC_P (from)
1273 && conv->rank < cr_pbool)
1274 || NULLPTR_TYPE_P (from))
1275 conv->rank = cr_pbool;
1281 /* We don't check for ENUMERAL_TYPE here because there are no standard
1282 conversions to enum type. */
1283 /* As an extension, allow conversion to complex type. */
1284 else if (ARITHMETIC_TYPE_P (to))
1286 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
1287 || SCOPED_ENUM_P (from))
1289 conv = build_conv (ck_std, to, conv);
1291 /* Give this a better rank if it's a promotion. */
1292 if (same_type_p (to, type_promotes_to (from))
1293 && conv->u.next->rank <= cr_promotion)
1294 conv->rank = cr_promotion;
1296 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
1297 && vector_types_convertible_p (from, to, false))
1298 return build_conv (ck_std, to, conv);
1299 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
1300 && is_properly_derived_from (from, to))
1302 if (conv->kind == ck_rvalue)
1303 conv = conv->u.next;
1304 conv = build_conv (ck_base, to, conv);
1305 /* The derived-to-base conversion indicates the initialization
1306 of a parameter with base type from an object of a derived
1307 type. A temporary object is created to hold the result of
1308 the conversion unless we're binding directly to a reference. */
1309 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
1314 if (flags & LOOKUP_NO_NARROWING)
1315 conv->check_narrowing = true;
1320 /* Returns nonzero if T1 is reference-related to T2. */
1323 reference_related_p (tree t1, tree t2)
1325 if (t1 == error_mark_node || t2 == error_mark_node)
1328 t1 = TYPE_MAIN_VARIANT (t1);
1329 t2 = TYPE_MAIN_VARIANT (t2);
1333 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1334 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1336 return (same_type_p (t1, t2)
1337 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1338 && DERIVED_FROM_P (t1, t2)));
1341 /* Returns nonzero if T1 is reference-compatible with T2. */
1344 reference_compatible_p (tree t1, tree t2)
1348 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1349 reference-related to T2 and cv1 is the same cv-qualification as,
1350 or greater cv-qualification than, cv2. */
1351 return (reference_related_p (t1, t2)
1352 && at_least_as_qualified_p (t1, t2));
1355 /* Determine whether or not the EXPR (of class type S) can be
1356 converted to T as in [over.match.ref]. */
1359 convert_class_to_reference_1 (tree reference_type, tree s, tree expr, int flags)
1365 struct z_candidate *candidates;
1366 struct z_candidate *cand;
1372 conversions = lookup_conversions (s);
1378 Assuming that "cv1 T" is the underlying type of the reference
1379 being initialized, and "cv S" is the type of the initializer
1380 expression, with S a class type, the candidate functions are
1381 selected as follows:
1383 --The conversion functions of S and its base classes are
1384 considered. Those that are not hidden within S and yield type
1385 "reference to cv2 T2", where "cv1 T" is reference-compatible
1386 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1388 The argument list has one argument, which is the initializer
1393 /* Conceptually, we should take the address of EXPR and put it in
1394 the argument list. Unfortunately, however, that can result in
1395 error messages, which we should not issue now because we are just
1396 trying to find a conversion operator. Therefore, we use NULL,
1397 cast to the appropriate type. */
1398 first_arg = build_int_cst (build_pointer_type (s), 0);
1400 t = TREE_TYPE (reference_type);
1402 /* We're performing a user-defined conversion to a desired type, so set
1403 this for the benefit of add_candidates. */
1404 flags |= LOOKUP_NO_CONVERSION;
1406 for (; conversions; conversions = TREE_CHAIN (conversions))
1408 tree fns = TREE_VALUE (conversions);
1409 tree binfo = TREE_PURPOSE (conversions);
1410 struct z_candidate *old_candidates = candidates;;
1412 add_candidates (fns, first_arg, NULL, reference_type,
1414 binfo, TYPE_BINFO (s),
1415 flags, &candidates);
1417 for (cand = candidates; cand != old_candidates; cand = cand->next)
1419 /* Now, see if the conversion function really returns
1420 an lvalue of the appropriate type. From the
1421 point of view of unification, simply returning an
1422 rvalue of the right type is good enough. */
1424 tree t2 = TREE_TYPE (TREE_TYPE (f));
1425 if (cand->viable == 0)
1426 /* Don't bother looking more closely. */;
1427 else if (TREE_CODE (t2) != REFERENCE_TYPE
1428 || !reference_compatible_p (t, TREE_TYPE (t2)))
1430 /* No need to set cand->reason here; this is most likely
1431 an ambiguous match. If it's not, either this candidate
1432 will win, or we will have identified a reason for it
1438 conversion *identity_conv;
1439 /* Build a standard conversion sequence indicating the
1440 binding from the reference type returned by the
1441 function to the desired REFERENCE_TYPE. */
1443 = build_identity_conv (TREE_TYPE (TREE_TYPE
1444 (TREE_TYPE (cand->fn))),
1447 = (direct_reference_binding
1448 (reference_type, identity_conv));
1449 cand->second_conv->rvaluedness_matches_p
1450 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1451 == TYPE_REF_IS_RVALUE (reference_type);
1452 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1454 /* Don't allow binding of lvalues to rvalue references. */
1455 if (TYPE_REF_IS_RVALUE (reference_type)
1456 /* Function lvalues are OK, though. */
1457 && TREE_CODE (TREE_TYPE (reference_type)) != FUNCTION_TYPE
1458 && !TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn))))
1459 cand->second_conv->bad_p = true;
1464 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1465 /* If none of the conversion functions worked out, let our caller
1470 cand = tourney (candidates);
1474 /* Now that we know that this is the function we're going to use fix
1475 the dummy first argument. */
1476 gcc_assert (cand->first_arg == NULL_TREE
1477 || integer_zerop (cand->first_arg));
1478 cand->first_arg = build_this (expr);
1480 /* Build a user-defined conversion sequence representing the
1482 conv = build_conv (ck_user,
1483 TREE_TYPE (TREE_TYPE (cand->fn)),
1484 build_identity_conv (TREE_TYPE (expr), expr));
1487 if (cand->viable == -1)
1490 /* Merge it with the standard conversion sequence from the
1491 conversion function's return type to the desired type. */
1492 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1494 return cand->second_conv;
1497 /* Wrapper for above. */
1500 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1503 bool subtime = timevar_cond_start (TV_OVERLOAD);
1504 ret = convert_class_to_reference_1 (reference_type, s, expr, flags);
1505 timevar_cond_stop (TV_OVERLOAD, subtime);
1509 /* A reference of the indicated TYPE is being bound directly to the
1510 expression represented by the implicit conversion sequence CONV.
1511 Return a conversion sequence for this binding. */
1514 direct_reference_binding (tree type, conversion *conv)
1518 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1519 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1521 t = TREE_TYPE (type);
1525 When a parameter of reference type binds directly
1526 (_dcl.init.ref_) to an argument expression, the implicit
1527 conversion sequence is the identity conversion, unless the
1528 argument expression has a type that is a derived class of the
1529 parameter type, in which case the implicit conversion sequence is
1530 a derived-to-base Conversion.
1532 If the parameter binds directly to the result of applying a
1533 conversion function to the argument expression, the implicit
1534 conversion sequence is a user-defined conversion sequence
1535 (_over.ics.user_), with the second standard conversion sequence
1536 either an identity conversion or, if the conversion function
1537 returns an entity of a type that is a derived class of the
1538 parameter type, a derived-to-base conversion. */
1539 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1541 /* Represent the derived-to-base conversion. */
1542 conv = build_conv (ck_base, t, conv);
1543 /* We will actually be binding to the base-class subobject in
1544 the derived class, so we mark this conversion appropriately.
1545 That way, convert_like knows not to generate a temporary. */
1546 conv->need_temporary_p = false;
1548 return build_conv (ck_ref_bind, type, conv);
1551 /* Returns the conversion path from type FROM to reference type TO for
1552 purposes of reference binding. For lvalue binding, either pass a
1553 reference type to FROM or an lvalue expression to EXPR. If the
1554 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1555 the conversion returned. If C_CAST_P is true, this
1556 conversion is coming from a C-style cast. */
1559 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1561 conversion *conv = NULL;
1562 tree to = TREE_TYPE (rto);
1567 cp_lvalue_kind gl_kind;
1570 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1572 expr = instantiate_type (to, expr, tf_none);
1573 if (expr == error_mark_node)
1575 from = TREE_TYPE (expr);
1578 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1580 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1581 conv = implicit_conversion (to, from, expr, c_cast_p,
1583 if (!CLASS_TYPE_P (to)
1584 && CONSTRUCTOR_NELTS (expr) == 1)
1586 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1587 if (error_operand_p (expr))
1589 from = TREE_TYPE (expr);
1593 if (TREE_CODE (from) == REFERENCE_TYPE)
1595 from = TREE_TYPE (from);
1596 if (!TYPE_REF_IS_RVALUE (rfrom)
1597 || TREE_CODE (from) == FUNCTION_TYPE)
1598 gl_kind = clk_ordinary;
1600 gl_kind = clk_rvalueref;
1604 gl_kind = lvalue_kind (expr);
1605 if (gl_kind & clk_class)
1606 /* A class prvalue is not a glvalue. */
1611 is_lvalue = gl_kind && !(gl_kind & clk_rvalueref);
1614 if ((gl_kind & clk_bitfield) != 0)
1615 tfrom = unlowered_expr_type (expr);
1617 /* Figure out whether or not the types are reference-related and
1618 reference compatible. We have do do this after stripping
1619 references from FROM. */
1620 related_p = reference_related_p (to, tfrom);
1621 /* If this is a C cast, first convert to an appropriately qualified
1622 type, so that we can later do a const_cast to the desired type. */
1623 if (related_p && c_cast_p
1624 && !at_least_as_qualified_p (to, tfrom))
1625 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1626 compatible_p = reference_compatible_p (to, tfrom);
1628 /* Directly bind reference when target expression's type is compatible with
1629 the reference and expression is an lvalue. In DR391, the wording in
1630 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1631 const and rvalue references to rvalues of compatible class type.
1632 We should also do direct bindings for non-class xvalues. */
1635 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1636 && !(flags & LOOKUP_NO_RVAL_BIND))
1637 || TYPE_REF_IS_RVALUE (rto))
1639 || (!(flags & LOOKUP_NO_TEMP_BIND)
1640 && (CLASS_TYPE_P (from)
1641 || TREE_CODE (from) == ARRAY_TYPE))))))
1645 If the initializer expression
1647 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1648 is reference-compatible with "cv2 T2,"
1650 the reference is bound directly to the initializer expression
1654 If the initializer expression is an rvalue, with T2 a class type,
1655 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1656 is bound to the object represented by the rvalue or to a sub-object
1657 within that object. */
1659 conv = build_identity_conv (tfrom, expr);
1660 conv = direct_reference_binding (rto, conv);
1662 if (flags & LOOKUP_PREFER_RVALUE)
1663 /* The top-level caller requested that we pretend that the lvalue
1664 be treated as an rvalue. */
1665 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1666 else if (TREE_CODE (rfrom) == REFERENCE_TYPE)
1667 /* Handle rvalue reference to function properly. */
1668 conv->rvaluedness_matches_p
1669 = (TYPE_REF_IS_RVALUE (rto) == TYPE_REF_IS_RVALUE (rfrom));
1671 conv->rvaluedness_matches_p
1672 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1674 if ((gl_kind & clk_bitfield) != 0
1675 || ((gl_kind & clk_packed) != 0 && !TYPE_PACKED (to)))
1676 /* For the purposes of overload resolution, we ignore the fact
1677 this expression is a bitfield or packed field. (In particular,
1678 [over.ics.ref] says specifically that a function with a
1679 non-const reference parameter is viable even if the
1680 argument is a bitfield.)
1682 However, when we actually call the function we must create
1683 a temporary to which to bind the reference. If the
1684 reference is volatile, or isn't const, then we cannot make
1685 a temporary, so we just issue an error when the conversion
1687 conv->need_temporary_p = true;
1689 /* Don't allow binding of lvalues (other than function lvalues) to
1690 rvalue references. */
1691 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1692 && TREE_CODE (to) != FUNCTION_TYPE
1693 && !(flags & LOOKUP_PREFER_RVALUE))
1698 /* [class.conv.fct] A conversion function is never used to convert a
1699 (possibly cv-qualified) object to the (possibly cv-qualified) same
1700 object type (or a reference to it), to a (possibly cv-qualified) base
1701 class of that type (or a reference to it).... */
1702 else if (CLASS_TYPE_P (from) && !related_p
1703 && !(flags & LOOKUP_NO_CONVERSION))
1707 If the initializer expression
1709 -- has a class type (i.e., T2 is a class type) can be
1710 implicitly converted to an lvalue of type "cv3 T3," where
1711 "cv1 T1" is reference-compatible with "cv3 T3". (this
1712 conversion is selected by enumerating the applicable
1713 conversion functions (_over.match.ref_) and choosing the
1714 best one through overload resolution. (_over.match_).
1716 the reference is bound to the lvalue result of the conversion
1717 in the second case. */
1718 conv = convert_class_to_reference (rto, from, expr, flags);
1723 /* From this point on, we conceptually need temporaries, even if we
1724 elide them. Only the cases above are "direct bindings". */
1725 if (flags & LOOKUP_NO_TEMP_BIND)
1730 When a parameter of reference type is not bound directly to an
1731 argument expression, the conversion sequence is the one required
1732 to convert the argument expression to the underlying type of the
1733 reference according to _over.best.ics_. Conceptually, this
1734 conversion sequence corresponds to copy-initializing a temporary
1735 of the underlying type with the argument expression. Any
1736 difference in top-level cv-qualification is subsumed by the
1737 initialization itself and does not constitute a conversion. */
1741 Otherwise, the reference shall be to a non-volatile const type.
1743 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1744 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1749 Otherwise, a temporary of type "cv1 T1" is created and
1750 initialized from the initializer expression using the rules for a
1751 non-reference copy initialization. If T1 is reference-related to
1752 T2, cv1 must be the same cv-qualification as, or greater
1753 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1754 if (related_p && !at_least_as_qualified_p (to, from))
1757 /* We're generating a temporary now, but don't bind any more in the
1758 conversion (specifically, don't slice the temporary returned by a
1759 conversion operator). */
1760 flags |= LOOKUP_NO_TEMP_BIND;
1762 /* Core issue 899: When [copy-]initializing a temporary to be bound
1763 to the first parameter of a copy constructor (12.8) called with
1764 a single argument in the context of direct-initialization,
1765 explicit conversion functions are also considered.
1767 So don't set LOOKUP_ONLYCONVERTING in that case. */
1768 if (!(flags & LOOKUP_COPY_PARM))
1769 flags |= LOOKUP_ONLYCONVERTING;
1772 conv = implicit_conversion (to, from, expr, c_cast_p,
1777 conv = build_conv (ck_ref_bind, rto, conv);
1778 /* This reference binding, unlike those above, requires the
1779 creation of a temporary. */
1780 conv->need_temporary_p = true;
1781 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1786 /* Returns the implicit conversion sequence (see [over.ics]) from type
1787 FROM to type TO. The optional expression EXPR may affect the
1788 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1789 true, this conversion is coming from a C-style cast. */
1792 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1797 if (from == error_mark_node || to == error_mark_node
1798 || expr == error_mark_node)
1801 if (TREE_CODE (to) == REFERENCE_TYPE)
1802 conv = reference_binding (to, from, expr, c_cast_p, flags);
1804 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1809 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1811 if (is_std_init_list (to))
1812 return build_list_conv (to, expr, flags);
1814 /* As an extension, allow list-initialization of _Complex. */
1815 if (TREE_CODE (to) == COMPLEX_TYPE)
1817 conv = build_complex_conv (to, expr, flags);
1822 /* Allow conversion from an initializer-list with one element to a
1824 if (SCALAR_TYPE_P (to))
1826 int nelts = CONSTRUCTOR_NELTS (expr);
1830 elt = build_value_init (to, tf_none);
1831 else if (nelts == 1)
1832 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1834 elt = error_mark_node;
1836 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1840 conv->check_narrowing = true;
1841 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1842 /* Too many levels of braces, i.e. '{{1}}'. */
1847 else if (TREE_CODE (to) == ARRAY_TYPE)
1848 return build_array_conv (to, expr, flags);
1851 if (expr != NULL_TREE
1852 && (MAYBE_CLASS_TYPE_P (from)
1853 || MAYBE_CLASS_TYPE_P (to))
1854 && (flags & LOOKUP_NO_CONVERSION) == 0)
1856 struct z_candidate *cand;
1857 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING
1858 |LOOKUP_NO_NARROWING));
1860 if (CLASS_TYPE_P (to)
1861 && BRACE_ENCLOSED_INITIALIZER_P (expr)
1862 && !CLASSTYPE_NON_AGGREGATE (complete_type (to)))
1863 return build_aggr_conv (to, expr, flags);
1865 cand = build_user_type_conversion_1 (to, expr, convflags);
1867 conv = cand->second_conv;
1869 /* We used to try to bind a reference to a temporary here, but that
1870 is now handled after the recursive call to this function at the end
1871 of reference_binding. */
1878 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1879 functions. ARGS will not be changed until a single candidate is
1882 static struct z_candidate *
1883 add_candidate (struct z_candidate **candidates,
1884 tree fn, tree first_arg, const VEC(tree,gc) *args,
1885 size_t num_convs, conversion **convs,
1886 tree access_path, tree conversion_path,
1887 int viable, struct rejection_reason *reason)
1889 struct z_candidate *cand = (struct z_candidate *)
1890 conversion_obstack_alloc (sizeof (struct z_candidate));
1893 cand->first_arg = first_arg;
1895 cand->convs = convs;
1896 cand->num_convs = num_convs;
1897 cand->access_path = access_path;
1898 cand->conversion_path = conversion_path;
1899 cand->viable = viable;
1900 cand->reason = reason;
1901 cand->next = *candidates;
1907 /* Return the number of remaining arguments in the parameter list
1908 beginning with ARG. */
1911 remaining_arguments (tree arg)
1915 for (n = 0; arg != NULL_TREE && arg != void_list_node;
1916 arg = TREE_CHAIN (arg))
1922 /* Create an overload candidate for the function or method FN called
1923 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1924 FLAGS is passed on to implicit_conversion.
1926 This does not change ARGS.
1928 CTYPE, if non-NULL, is the type we want to pretend this function
1929 comes from for purposes of overload resolution. */
1931 static struct z_candidate *
1932 add_function_candidate (struct z_candidate **candidates,
1933 tree fn, tree ctype, tree first_arg,
1934 const VEC(tree,gc) *args, tree access_path,
1935 tree conversion_path, int flags)
1937 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1941 tree orig_first_arg = first_arg;
1944 struct rejection_reason *reason = NULL;
1946 /* At this point we should not see any functions which haven't been
1947 explicitly declared, except for friend functions which will have
1948 been found using argument dependent lookup. */
1949 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1951 /* The `this', `in_chrg' and VTT arguments to constructors are not
1952 considered in overload resolution. */
1953 if (DECL_CONSTRUCTOR_P (fn))
1955 parmlist = skip_artificial_parms_for (fn, parmlist);
1956 skip = num_artificial_parms_for (fn);
1957 if (skip > 0 && first_arg != NULL_TREE)
1960 first_arg = NULL_TREE;
1966 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1967 convs = alloc_conversions (len);
1969 /* 13.3.2 - Viable functions [over.match.viable]
1970 First, to be a viable function, a candidate function shall have enough
1971 parameters to agree in number with the arguments in the list.
1973 We need to check this first; otherwise, checking the ICSes might cause
1974 us to produce an ill-formed template instantiation. */
1976 parmnode = parmlist;
1977 for (i = 0; i < len; ++i)
1979 if (parmnode == NULL_TREE || parmnode == void_list_node)
1981 parmnode = TREE_CHAIN (parmnode);
1984 if ((i < len && parmnode)
1985 || !sufficient_parms_p (parmnode))
1987 int remaining = remaining_arguments (parmnode);
1989 reason = arity_rejection (first_arg, i + remaining, len);
1991 /* When looking for a function from a subobject from an implicit
1992 copy/move constructor/operator=, don't consider anything that takes (a
1993 reference to) an unrelated type. See c++/44909 and core 1092. */
1994 else if (parmlist && (flags & LOOKUP_DEFAULTED))
1996 if (DECL_CONSTRUCTOR_P (fn))
1998 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
1999 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
2005 parmnode = chain_index (i-1, parmlist);
2006 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
2011 /* This only applies at the top level. */
2012 flags &= ~LOOKUP_DEFAULTED;
2018 /* Second, for F to be a viable function, there shall exist for each
2019 argument an implicit conversion sequence that converts that argument
2020 to the corresponding parameter of F. */
2022 parmnode = parmlist;
2024 for (i = 0; i < len; ++i)
2026 tree arg, argtype, to_type;
2030 if (parmnode == void_list_node)
2033 if (i == 0 && first_arg != NULL_TREE)
2036 arg = VEC_index (tree, args,
2037 i + skip - (first_arg != NULL_TREE ? 1 : 0));
2038 argtype = lvalue_type (arg);
2040 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
2041 && ! DECL_CONSTRUCTOR_P (fn));
2045 tree parmtype = TREE_VALUE (parmnode);
2048 parmnode = TREE_CHAIN (parmnode);
2050 /* The type of the implicit object parameter ('this') for
2051 overload resolution is not always the same as for the
2052 function itself; conversion functions are considered to
2053 be members of the class being converted, and functions
2054 introduced by a using-declaration are considered to be
2055 members of the class that uses them.
2057 Since build_over_call ignores the ICS for the `this'
2058 parameter, we can just change the parm type. */
2059 if (ctype && is_this)
2061 parmtype = cp_build_qualified_type
2062 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
2063 parmtype = build_pointer_type (parmtype);
2066 /* Core issue 899: When [copy-]initializing a temporary to be bound
2067 to the first parameter of a copy constructor (12.8) called with
2068 a single argument in the context of direct-initialization,
2069 explicit conversion functions are also considered.
2071 So set LOOKUP_COPY_PARM to let reference_binding know that
2072 it's being called in that context. We generalize the above
2073 to handle move constructors and template constructors as well;
2074 the standardese should soon be updated similarly. */
2075 if (ctype && i == 0 && (len-skip == 1)
2076 && !(flags & LOOKUP_ONLYCONVERTING)
2077 && DECL_CONSTRUCTOR_P (fn)
2078 && parmtype != error_mark_node
2079 && (same_type_ignoring_top_level_qualifiers_p
2080 (non_reference (parmtype), ctype)))
2082 lflags |= LOOKUP_COPY_PARM;
2083 /* We allow user-defined conversions within init-lists, but
2084 not for the copy constructor. */
2085 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
2086 lflags |= LOOKUP_NO_CONVERSION;
2089 lflags |= LOOKUP_ONLYCONVERTING;
2091 t = implicit_conversion (parmtype, argtype, arg,
2092 /*c_cast_p=*/false, lflags);
2097 t = build_identity_conv (argtype, arg);
2098 t->ellipsis_p = true;
2109 reason = arg_conversion_rejection (first_arg, i, argtype, to_type);
2116 reason = bad_arg_conversion_rejection (first_arg, i, argtype, to_type);
2121 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
2122 access_path, conversion_path, viable, reason);
2125 /* Create an overload candidate for the conversion function FN which will
2126 be invoked for expression OBJ, producing a pointer-to-function which
2127 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2128 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2129 passed on to implicit_conversion.
2131 Actually, we don't really care about FN; we care about the type it
2132 converts to. There may be multiple conversion functions that will
2133 convert to that type, and we rely on build_user_type_conversion_1 to
2134 choose the best one; so when we create our candidate, we record the type
2135 instead of the function. */
2137 static struct z_candidate *
2138 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
2139 tree first_arg, const VEC(tree,gc) *arglist,
2140 tree access_path, tree conversion_path)
2142 tree totype = TREE_TYPE (TREE_TYPE (fn));
2143 int i, len, viable, flags;
2144 tree parmlist, parmnode;
2146 struct rejection_reason *reason;
2148 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
2149 parmlist = TREE_TYPE (parmlist);
2150 parmlist = TYPE_ARG_TYPES (parmlist);
2152 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
2153 convs = alloc_conversions (len);
2154 parmnode = parmlist;
2156 flags = LOOKUP_IMPLICIT;
2159 /* Don't bother looking up the same type twice. */
2160 if (*candidates && (*candidates)->fn == totype)
2163 for (i = 0; i < len; ++i)
2165 tree arg, argtype, convert_type = NULL_TREE;
2170 else if (i == 1 && first_arg != NULL_TREE)
2173 arg = VEC_index (tree, arglist,
2174 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
2175 argtype = lvalue_type (arg);
2179 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
2181 convert_type = totype;
2183 else if (parmnode == void_list_node)
2187 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
2188 /*c_cast_p=*/false, flags);
2189 convert_type = TREE_VALUE (parmnode);
2193 t = build_identity_conv (argtype, arg);
2194 t->ellipsis_p = true;
2195 convert_type = argtype;
2205 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtype, convert_type);
2212 parmnode = TREE_CHAIN (parmnode);
2216 || ! sufficient_parms_p (parmnode))
2218 int remaining = remaining_arguments (parmnode);
2220 reason = arity_rejection (NULL_TREE, i + remaining, len);
2223 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
2224 access_path, conversion_path, viable, reason);
2228 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
2229 tree type1, tree type2, tree *args, tree *argtypes,
2237 struct rejection_reason *reason = NULL;
2242 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
2243 convs = alloc_conversions (num_convs);
2245 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2246 conversion ops are allowed. We handle that here by just checking for
2247 boolean_type_node because other operators don't ask for it. COND_EXPR
2248 also does contextual conversion to bool for the first operand, but we
2249 handle that in build_conditional_expr, and type1 here is operand 2. */
2250 if (type1 != boolean_type_node)
2251 flags |= LOOKUP_ONLYCONVERTING;
2253 for (i = 0; i < 2; ++i)
2258 t = implicit_conversion (types[i], argtypes[i], args[i],
2259 /*c_cast_p=*/false, flags);
2263 /* We need something for printing the candidate. */
2264 t = build_identity_conv (types[i], NULL_TREE);
2265 reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2270 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2275 /* For COND_EXPR we rearranged the arguments; undo that now. */
2278 convs[2] = convs[1];
2279 convs[1] = convs[0];
2280 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
2281 /*c_cast_p=*/false, flags);
2287 reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2],
2292 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
2294 /*access_path=*/NULL_TREE,
2295 /*conversion_path=*/NULL_TREE,
2300 is_complete (tree t)
2302 return COMPLETE_TYPE_P (complete_type (t));
2305 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2308 promoted_arithmetic_type_p (tree type)
2312 In this section, the term promoted integral type is used to refer
2313 to those integral types which are preserved by integral promotion
2314 (including e.g. int and long but excluding e.g. char).
2315 Similarly, the term promoted arithmetic type refers to promoted
2316 integral types plus floating types. */
2317 return ((CP_INTEGRAL_TYPE_P (type)
2318 && same_type_p (type_promotes_to (type), type))
2319 || TREE_CODE (type) == REAL_TYPE);
2322 /* Create any builtin operator overload candidates for the operator in
2323 question given the converted operand types TYPE1 and TYPE2. The other
2324 args are passed through from add_builtin_candidates to
2325 build_builtin_candidate.
2327 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2328 If CODE is requires candidates operands of the same type of the kind
2329 of which TYPE1 and TYPE2 are, we add both candidates
2330 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2333 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
2334 enum tree_code code2, tree fnname, tree type1,
2335 tree type2, tree *args, tree *argtypes, int flags)
2339 case POSTINCREMENT_EXPR:
2340 case POSTDECREMENT_EXPR:
2341 args[1] = integer_zero_node;
2342 type2 = integer_type_node;
2351 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2352 and VQ is either volatile or empty, there exist candidate operator
2353 functions of the form
2354 VQ T& operator++(VQ T&);
2355 T operator++(VQ T&, int);
2356 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2357 type other than bool, and VQ is either volatile or empty, there exist
2358 candidate operator functions of the form
2359 VQ T& operator--(VQ T&);
2360 T operator--(VQ T&, int);
2361 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2362 complete object type, and VQ is either volatile or empty, there exist
2363 candidate operator functions of the form
2364 T*VQ& operator++(T*VQ&);
2365 T*VQ& operator--(T*VQ&);
2366 T* operator++(T*VQ&, int);
2367 T* operator--(T*VQ&, int); */
2369 case POSTDECREMENT_EXPR:
2370 case PREDECREMENT_EXPR:
2371 if (TREE_CODE (type1) == BOOLEAN_TYPE)
2373 case POSTINCREMENT_EXPR:
2374 case PREINCREMENT_EXPR:
2375 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
2377 type1 = build_reference_type (type1);
2382 /* 7 For every cv-qualified or cv-unqualified object type T, there
2383 exist candidate operator functions of the form
2387 8 For every function type T, there exist candidate operator functions of
2389 T& operator*(T*); */
2392 if (TREE_CODE (type1) == POINTER_TYPE
2393 && !uses_template_parms (TREE_TYPE (type1))
2394 && (TYPE_PTROB_P (type1)
2395 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
2399 /* 9 For every type T, there exist candidate operator functions of the form
2402 10For every promoted arithmetic type T, there exist candidate operator
2403 functions of the form
2407 case UNARY_PLUS_EXPR: /* unary + */
2408 if (TREE_CODE (type1) == POINTER_TYPE)
2411 if (ARITHMETIC_TYPE_P (type1))
2415 /* 11For every promoted integral type T, there exist candidate operator
2416 functions of the form
2420 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2424 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2425 is the same type as C2 or is a derived class of C2, T is a complete
2426 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2427 there exist candidate operator functions of the form
2428 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2429 where CV12 is the union of CV1 and CV2. */
2432 if (TREE_CODE (type1) == POINTER_TYPE
2433 && TYPE_PTR_TO_MEMBER_P (type2))
2435 tree c1 = TREE_TYPE (type1);
2436 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2438 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2439 && (TYPE_PTRMEMFUNC_P (type2)
2440 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2445 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2446 didate operator functions of the form
2451 bool operator<(L, R);
2452 bool operator>(L, R);
2453 bool operator<=(L, R);
2454 bool operator>=(L, R);
2455 bool operator==(L, R);
2456 bool operator!=(L, R);
2457 where LR is the result of the usual arithmetic conversions between
2460 14For every pair of types T and I, where T is a cv-qualified or cv-
2461 unqualified complete object type and I is a promoted integral type,
2462 there exist candidate operator functions of the form
2463 T* operator+(T*, I);
2464 T& operator[](T*, I);
2465 T* operator-(T*, I);
2466 T* operator+(I, T*);
2467 T& operator[](I, T*);
2469 15For every T, where T is a pointer to complete object type, there exist
2470 candidate operator functions of the form112)
2471 ptrdiff_t operator-(T, T);
2473 16For every pointer or enumeration type T, there exist candidate operator
2474 functions of the form
2475 bool operator<(T, T);
2476 bool operator>(T, T);
2477 bool operator<=(T, T);
2478 bool operator>=(T, T);
2479 bool operator==(T, T);
2480 bool operator!=(T, T);
2482 17For every pointer to member type T, there exist candidate operator
2483 functions of the form
2484 bool operator==(T, T);
2485 bool operator!=(T, T); */
2488 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2490 if (TYPE_PTROB_P (type1)
2491 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2493 type2 = ptrdiff_type_node;
2497 case TRUNC_DIV_EXPR:
2498 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2504 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2505 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2507 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2512 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2524 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2526 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2528 if (TREE_CODE (type1) == ENUMERAL_TYPE
2529 && TREE_CODE (type2) == ENUMERAL_TYPE)
2531 if (TYPE_PTR_P (type1)
2532 && null_ptr_cst_p (args[1])
2533 && !uses_template_parms (type1))
2538 if (null_ptr_cst_p (args[0])
2539 && TYPE_PTR_P (type2)
2540 && !uses_template_parms (type2))
2548 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2551 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2553 type1 = ptrdiff_type_node;
2556 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2558 type2 = ptrdiff_type_node;
2563 /* 18For every pair of promoted integral types L and R, there exist candi-
2564 date operator functions of the form
2571 where LR is the result of the usual arithmetic conversions between
2574 case TRUNC_MOD_EXPR:
2580 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2584 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2585 type, VQ is either volatile or empty, and R is a promoted arithmetic
2586 type, there exist candidate operator functions of the form
2587 VQ L& operator=(VQ L&, R);
2588 VQ L& operator*=(VQ L&, R);
2589 VQ L& operator/=(VQ L&, R);
2590 VQ L& operator+=(VQ L&, R);
2591 VQ L& operator-=(VQ L&, R);
2593 20For every pair T, VQ), where T is any type and VQ is either volatile
2594 or empty, there exist candidate operator functions of the form
2595 T*VQ& operator=(T*VQ&, T*);
2597 21For every pair T, VQ), where T is a pointer to member type and VQ is
2598 either volatile or empty, there exist candidate operator functions of
2600 VQ T& operator=(VQ T&, T);
2602 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2603 unqualified complete object type, VQ is either volatile or empty, and
2604 I is a promoted integral type, there exist candidate operator func-
2606 T*VQ& operator+=(T*VQ&, I);
2607 T*VQ& operator-=(T*VQ&, I);
2609 23For every triple L, VQ, R), where L is an integral or enumeration
2610 type, VQ is either volatile or empty, and R is a promoted integral
2611 type, there exist candidate operator functions of the form
2613 VQ L& operator%=(VQ L&, R);
2614 VQ L& operator<<=(VQ L&, R);
2615 VQ L& operator>>=(VQ L&, R);
2616 VQ L& operator&=(VQ L&, R);
2617 VQ L& operator^=(VQ L&, R);
2618 VQ L& operator|=(VQ L&, R); */
2625 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2627 type2 = ptrdiff_type_node;
2631 case TRUNC_DIV_EXPR:
2632 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2636 case TRUNC_MOD_EXPR:
2642 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2647 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2649 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2650 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2651 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2652 || ((TYPE_PTRMEMFUNC_P (type1)
2653 || TREE_CODE (type1) == POINTER_TYPE)
2654 && null_ptr_cst_p (args[1])))
2664 type1 = build_reference_type (type1);
2670 For every pair of promoted arithmetic types L and R, there
2671 exist candidate operator functions of the form
2673 LR operator?(bool, L, R);
2675 where LR is the result of the usual arithmetic conversions
2676 between types L and R.
2678 For every type T, where T is a pointer or pointer-to-member
2679 type, there exist candidate operator functions of the form T
2680 operator?(bool, T, T); */
2682 if (promoted_arithmetic_type_p (type1)
2683 && promoted_arithmetic_type_p (type2))
2687 /* Otherwise, the types should be pointers. */
2688 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2689 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2692 /* We don't check that the two types are the same; the logic
2693 below will actually create two candidates; one in which both
2694 parameter types are TYPE1, and one in which both parameter
2700 if (ARITHMETIC_TYPE_P (type1))
2708 /* If we're dealing with two pointer types or two enumeral types,
2709 we need candidates for both of them. */
2710 if (type2 && !same_type_p (type1, type2)
2711 && TREE_CODE (type1) == TREE_CODE (type2)
2712 && (TREE_CODE (type1) == REFERENCE_TYPE
2713 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2714 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2715 || TYPE_PTRMEMFUNC_P (type1)
2716 || MAYBE_CLASS_TYPE_P (type1)
2717 || TREE_CODE (type1) == ENUMERAL_TYPE))
2719 build_builtin_candidate
2720 (candidates, fnname, type1, type1, args, argtypes, flags);
2721 build_builtin_candidate
2722 (candidates, fnname, type2, type2, args, argtypes, flags);
2726 build_builtin_candidate
2727 (candidates, fnname, type1, type2, args, argtypes, flags);
2731 type_decays_to (tree type)
2733 if (TREE_CODE (type) == ARRAY_TYPE)
2734 return build_pointer_type (TREE_TYPE (type));
2735 if (TREE_CODE (type) == FUNCTION_TYPE)
2736 return build_pointer_type (type);
2740 /* There are three conditions of builtin candidates:
2742 1) bool-taking candidates. These are the same regardless of the input.
2743 2) pointer-pair taking candidates. These are generated for each type
2744 one of the input types converts to.
2745 3) arithmetic candidates. According to the standard, we should generate
2746 all of these, but I'm trying not to...
2748 Here we generate a superset of the possible candidates for this particular
2749 case. That is a subset of the full set the standard defines, plus some
2750 other cases which the standard disallows. add_builtin_candidate will
2751 filter out the invalid set. */
2754 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2755 enum tree_code code2, tree fnname, tree *args,
2760 tree type, argtypes[3], t;
2761 /* TYPES[i] is the set of possible builtin-operator parameter types
2762 we will consider for the Ith argument. */
2763 VEC(tree,gc) *types[2];
2766 for (i = 0; i < 3; ++i)
2769 argtypes[i] = unlowered_expr_type (args[i]);
2771 argtypes[i] = NULL_TREE;
2776 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2777 and VQ is either volatile or empty, there exist candidate operator
2778 functions of the form
2779 VQ T& operator++(VQ T&); */
2781 case POSTINCREMENT_EXPR:
2782 case PREINCREMENT_EXPR:
2783 case POSTDECREMENT_EXPR:
2784 case PREDECREMENT_EXPR:
2789 /* 24There also exist candidate operator functions of the form
2790 bool operator!(bool);
2791 bool operator&&(bool, bool);
2792 bool operator||(bool, bool); */
2794 case TRUTH_NOT_EXPR:
2795 build_builtin_candidate
2796 (candidates, fnname, boolean_type_node,
2797 NULL_TREE, args, argtypes, flags);
2800 case TRUTH_ORIF_EXPR:
2801 case TRUTH_ANDIF_EXPR:
2802 build_builtin_candidate
2803 (candidates, fnname, boolean_type_node,
2804 boolean_type_node, args, argtypes, flags);
2826 types[0] = make_tree_vector ();
2827 types[1] = make_tree_vector ();
2829 for (i = 0; i < 2; ++i)
2833 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2837 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2840 convs = lookup_conversions (argtypes[i]);
2842 if (code == COND_EXPR)
2844 if (real_lvalue_p (args[i]))
2845 VEC_safe_push (tree, gc, types[i],
2846 build_reference_type (argtypes[i]));
2848 VEC_safe_push (tree, gc, types[i],
2849 TYPE_MAIN_VARIANT (argtypes[i]));
2855 for (; convs; convs = TREE_CHAIN (convs))
2857 type = TREE_TYPE (convs);
2860 && (TREE_CODE (type) != REFERENCE_TYPE
2861 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2864 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2865 VEC_safe_push (tree, gc, types[i], type);
2867 type = non_reference (type);
2868 if (i != 0 || ! ref1)
2870 type = cv_unqualified (type_decays_to (type));
2871 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2872 VEC_safe_push (tree, gc, types[i], type);
2873 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2874 type = type_promotes_to (type);
2877 if (! vec_member (type, types[i]))
2878 VEC_safe_push (tree, gc, types[i], type);
2883 if (code == COND_EXPR && real_lvalue_p (args[i]))
2884 VEC_safe_push (tree, gc, types[i],
2885 build_reference_type (argtypes[i]));
2886 type = non_reference (argtypes[i]);
2887 if (i != 0 || ! ref1)
2889 type = cv_unqualified (type_decays_to (type));
2890 if (enum_p && UNSCOPED_ENUM_P (type))
2891 VEC_safe_push (tree, gc, types[i], type);
2892 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2893 type = type_promotes_to (type);
2895 VEC_safe_push (tree, gc, types[i], type);
2899 /* Run through the possible parameter types of both arguments,
2900 creating candidates with those parameter types. */
2901 FOR_EACH_VEC_ELT_REVERSE (tree, types[0], ix, t)
2906 if (!VEC_empty (tree, types[1]))
2907 FOR_EACH_VEC_ELT_REVERSE (tree, types[1], jx, u)
2908 add_builtin_candidate
2909 (candidates, code, code2, fnname, t,
2910 u, args, argtypes, flags);
2912 add_builtin_candidate
2913 (candidates, code, code2, fnname, t,
2914 NULL_TREE, args, argtypes, flags);
2917 release_tree_vector (types[0]);
2918 release_tree_vector (types[1]);
2922 /* If TMPL can be successfully instantiated as indicated by
2923 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2925 TMPL is the template. EXPLICIT_TARGS are any explicit template
2926 arguments. ARGLIST is the arguments provided at the call-site.
2927 This does not change ARGLIST. The RETURN_TYPE is the desired type
2928 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2929 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2930 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2932 static struct z_candidate*
2933 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2934 tree ctype, tree explicit_targs, tree first_arg,
2935 const VEC(tree,gc) *arglist, tree return_type,
2936 tree access_path, tree conversion_path,
2937 int flags, tree obj, unification_kind_t strict)
2939 int ntparms = DECL_NTPARMS (tmpl);
2940 tree targs = make_tree_vec (ntparms);
2941 unsigned int len = VEC_length (tree, arglist);
2942 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2943 unsigned int skip_without_in_chrg = 0;
2944 tree first_arg_without_in_chrg = first_arg;
2945 tree *args_without_in_chrg;
2946 unsigned int nargs_without_in_chrg;
2947 unsigned int ia, ix;
2949 struct z_candidate *cand;
2952 struct rejection_reason *reason = NULL;
2955 /* We don't do deduction on the in-charge parameter, the VTT
2956 parameter or 'this'. */
2957 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2959 if (first_arg_without_in_chrg != NULL_TREE)
2960 first_arg_without_in_chrg = NULL_TREE;
2962 ++skip_without_in_chrg;
2965 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2966 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2967 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2969 if (first_arg_without_in_chrg != NULL_TREE)
2970 first_arg_without_in_chrg = NULL_TREE;
2972 ++skip_without_in_chrg;
2975 if (len < skip_without_in_chrg)
2978 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2979 + (len - skip_without_in_chrg));
2980 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2982 if (first_arg_without_in_chrg != NULL_TREE)
2984 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2987 for (ix = skip_without_in_chrg;
2988 VEC_iterate (tree, arglist, ix, arg);
2991 args_without_in_chrg[ia] = arg;
2994 gcc_assert (ia == nargs_without_in_chrg);
2996 errs = errorcount+sorrycount;
2997 i = fn_type_unification (tmpl, explicit_targs, targs,
2998 args_without_in_chrg,
2999 nargs_without_in_chrg,
3000 return_type, strict, flags, false);
3004 /* Don't repeat unification later if it already resulted in errors. */
3005 if (errorcount+sorrycount == errs)
3006 reason = template_unification_rejection (tmpl, explicit_targs,
3007 targs, args_without_in_chrg,
3008 nargs_without_in_chrg,
3009 return_type, strict, flags);
3011 reason = template_unification_error_rejection ();
3015 fn = instantiate_template (tmpl, targs, tf_none);
3016 if (fn == error_mark_node)
3018 reason = template_instantiation_rejection (tmpl, targs);
3024 A member function template is never instantiated to perform the
3025 copy of a class object to an object of its class type.
3027 It's a little unclear what this means; the standard explicitly
3028 does allow a template to be used to copy a class. For example,
3033 template <class T> A(const T&);
3036 void g () { A a (f ()); }
3038 the member template will be used to make the copy. The section
3039 quoted above appears in the paragraph that forbids constructors
3040 whose only parameter is (a possibly cv-qualified variant of) the
3041 class type, and a logical interpretation is that the intent was
3042 to forbid the instantiation of member templates which would then
3044 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
3046 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
3047 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
3050 reason = invalid_copy_with_fn_template_rejection ();
3055 if (obj != NULL_TREE)
3056 /* Aha, this is a conversion function. */
3057 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
3058 access_path, conversion_path);
3060 cand = add_function_candidate (candidates, fn, ctype,
3061 first_arg, arglist, access_path,
3062 conversion_path, flags);
3063 if (DECL_TI_TEMPLATE (fn) != tmpl)
3064 /* This situation can occur if a member template of a template
3065 class is specialized. Then, instantiate_template might return
3066 an instantiation of the specialization, in which case the
3067 DECL_TI_TEMPLATE field will point at the original
3068 specialization. For example:
3070 template <class T> struct S { template <class U> void f(U);
3071 template <> void f(int) {}; };
3075 Here, TMPL will be template <class U> S<double>::f(U).
3076 And, instantiate template will give us the specialization
3077 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3078 for this will point at template <class T> template <> S<T>::f(int),
3079 so that we can find the definition. For the purposes of
3080 overload resolution, however, we want the original TMPL. */
3081 cand->template_decl = build_template_info (tmpl, targs);
3083 cand->template_decl = DECL_TEMPLATE_INFO (fn);
3084 cand->explicit_targs = explicit_targs;
3088 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
3089 access_path, conversion_path, 0, reason);
3093 static struct z_candidate *
3094 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
3095 tree explicit_targs, tree first_arg,
3096 const VEC(tree,gc) *arglist, tree return_type,
3097 tree access_path, tree conversion_path, int flags,
3098 unification_kind_t strict)
3101 add_template_candidate_real (candidates, tmpl, ctype,
3102 explicit_targs, first_arg, arglist,
3103 return_type, access_path, conversion_path,
3104 flags, NULL_TREE, strict);
3108 static struct z_candidate *
3109 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
3110 tree obj, tree first_arg,
3111 const VEC(tree,gc) *arglist,
3112 tree return_type, tree access_path,
3113 tree conversion_path)
3116 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
3117 first_arg, arglist, return_type, access_path,
3118 conversion_path, 0, obj, DEDUCE_CONV);
3121 /* The CANDS are the set of candidates that were considered for
3122 overload resolution. Return the set of viable candidates, or CANDS
3123 if none are viable. If any of the candidates were viable, set
3124 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3125 considered viable only if it is strictly viable. */
3127 static struct z_candidate*
3128 splice_viable (struct z_candidate *cands,
3132 struct z_candidate *viable;
3133 struct z_candidate **last_viable;
3134 struct z_candidate **cand;
3136 /* Be strict inside templates, since build_over_call won't actually
3137 do the conversions to get pedwarns. */
3138 if (processing_template_decl)
3142 last_viable = &viable;
3143 *any_viable_p = false;
3148 struct z_candidate *c = *cand;
3149 if (strict_p ? c->viable == 1 : c->viable)
3154 last_viable = &c->next;
3155 *any_viable_p = true;
3161 return viable ? viable : cands;
3165 any_strictly_viable (struct z_candidate *cands)
3167 for (; cands; cands = cands->next)
3168 if (cands->viable == 1)
3173 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3174 words, it is about to become the "this" pointer for a member
3175 function call. Take the address of the object. */
3178 build_this (tree obj)
3180 /* In a template, we are only concerned about the type of the
3181 expression, so we can take a shortcut. */
3182 if (processing_template_decl)
3183 return build_address (obj);
3185 return cp_build_addr_expr (obj, tf_warning_or_error);
3188 /* Returns true iff functions are equivalent. Equivalent functions are
3189 not '==' only if one is a function-local extern function or if
3190 both are extern "C". */
3193 equal_functions (tree fn1, tree fn2)
3195 if (TREE_CODE (fn1) != TREE_CODE (fn2))
3197 if (TREE_CODE (fn1) == TEMPLATE_DECL)
3199 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
3200 || DECL_EXTERN_C_FUNCTION_P (fn1))
3201 return decls_match (fn1, fn2);
3205 /* Print information about a candidate being rejected due to INFO. */
3208 print_conversion_rejection (location_t loc, struct conversion_info *info)
3210 if (info->n_arg == -1)
3211 /* Conversion of implicit `this' argument failed. */
3212 inform (loc, " no known conversion for implicit "
3213 "%<this%> parameter from %qT to %qT",
3214 info->from_type, info->to_type);
3216 inform (loc, " no known conversion for argument %d from %qT to %qT",
3217 info->n_arg+1, info->from_type, info->to_type);
3220 /* Print information about a candidate with WANT parameters and we found
3224 print_arity_information (location_t loc, unsigned int have, unsigned int want)
3226 inform_n (loc, want,
3227 " candidate expects %d argument, %d provided",
3228 " candidate expects %d arguments, %d provided",
3232 /* Print information about one overload candidate CANDIDATE. MSGSTR
3233 is the text to print before the candidate itself.
3235 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3236 to have been run through gettext by the caller. This wart makes
3237 life simpler in print_z_candidates and for the translators. */
3240 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
3242 const char *msg = (msgstr == NULL
3244 : ACONCAT ((msgstr, " ", NULL)));
3245 location_t loc = location_of (candidate->fn);
3247 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
3249 if (candidate->num_convs == 3)
3250 inform (input_location, "%s%D(%T, %T, %T) <built-in>", msg, candidate->fn,
3251 candidate->convs[0]->type,
3252 candidate->convs[1]->type,
3253 candidate->convs[2]->type);
3254 else if (candidate->num_convs == 2)
3255 inform (input_location, "%s%D(%T, %T) <built-in>", msg, candidate->fn,
3256 candidate->convs[0]->type,
3257 candidate->convs[1]->type);
3259 inform (input_location, "%s%D(%T) <built-in>", msg, candidate->fn,
3260 candidate->convs[0]->type);
3262 else if (TYPE_P (candidate->fn))
3263 inform (input_location, "%s%T <conversion>", msg, candidate->fn);
3264 else if (candidate->viable == -1)
3265 inform (loc, "%s%#D <near match>", msg, candidate->fn);
3266 else if (DECL_DELETED_FN (STRIP_TEMPLATE (candidate->fn)))
3267 inform (loc, "%s%#D <deleted>", msg, candidate->fn);
3269 inform (loc, "%s%#D", msg, candidate->fn);
3270 /* Give the user some information about why this candidate failed. */
3271 if (candidate->reason != NULL)
3273 struct rejection_reason *r = candidate->reason;
3278 print_arity_information (loc, r->u.arity.actual,
3279 r->u.arity.expected);
3281 case rr_arg_conversion:
3282 print_conversion_rejection (loc, &r->u.conversion);
3284 case rr_bad_arg_conversion:
3285 print_conversion_rejection (loc, &r->u.bad_conversion);
3287 case rr_explicit_conversion:
3288 inform (loc, " return type %qT of explicit conversion function "
3289 "cannot be converted to %qT with a qualification "
3290 "conversion", r->u.conversion.from_type,
3291 r->u.conversion.to_type);
3293 case rr_template_unification:
3294 /* We use template_unification_error_rejection if unification caused
3295 actual non-SFINAE errors, in which case we don't need to repeat
3297 if (r->u.template_unification.tmpl == NULL_TREE)
3299 inform (loc, " substitution of deduced template arguments "
3300 "resulted in errors seen above");
3303 /* Re-run template unification with diagnostics. */
3304 inform (loc, " template argument deduction/substitution failed:");
3305 fn_type_unification (r->u.template_unification.tmpl,
3306 r->u.template_unification.explicit_targs,
3307 r->u.template_unification.targs,
3308 r->u.template_unification.args,
3309 r->u.template_unification.nargs,
3310 r->u.template_unification.return_type,
3311 r->u.template_unification.strict,
3312 r->u.template_unification.flags,
3315 case rr_template_instantiation:
3316 /* Re-run template instantiation with diagnostics. */
3317 instantiate_template (r->u.template_instantiation.tmpl,
3318 r->u.template_instantiation.targs,
3319 tf_warning_or_error);
3321 case rr_invalid_copy:
3323 " a constructor taking a single argument of its own "
3324 "class type is invalid");
3328 /* This candidate didn't have any issues or we failed to
3329 handle a particular code. Either way... */
3336 print_z_candidates (location_t loc, struct z_candidate *candidates)
3338 struct z_candidate *cand1;
3339 struct z_candidate **cand2;
3345 /* Remove non-viable deleted candidates. */
3347 for (cand2 = &cand1; *cand2; )
3349 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
3350 && !(*cand2)->viable
3351 && DECL_DELETED_FN ((*cand2)->fn))
3352 *cand2 = (*cand2)->next;
3354 cand2 = &(*cand2)->next;
3356 /* ...if there are any non-deleted ones. */
3360 /* There may be duplicates in the set of candidates. We put off
3361 checking this condition as long as possible, since we have no way
3362 to eliminate duplicates from a set of functions in less than n^2
3363 time. Now we are about to emit an error message, so it is more
3364 permissible to go slowly. */
3365 for (cand1 = candidates; cand1; cand1 = cand1->next)
3367 tree fn = cand1->fn;
3368 /* Skip builtin candidates and conversion functions. */
3371 cand2 = &cand1->next;
3374 if (DECL_P ((*cand2)->fn)
3375 && equal_functions (fn, (*cand2)->fn))
3376 *cand2 = (*cand2)->next;
3378 cand2 = &(*cand2)->next;
3382 for (n_candidates = 0, cand1 = candidates; cand1; cand1 = cand1->next)
3385 inform_n (loc, n_candidates, "candidate is:", "candidates are:");
3386 for (; candidates; candidates = candidates->next)
3387 print_z_candidate (NULL, candidates);
3390 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3391 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3392 the result of the conversion function to convert it to the final
3393 desired type. Merge the two sequences into a single sequence,
3394 and return the merged sequence. */
3397 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
3401 gcc_assert (user_seq->kind == ck_user);
3403 /* Find the end of the second conversion sequence. */
3405 while ((*t)->kind != ck_identity)
3406 t = &((*t)->u.next);
3408 /* Replace the identity conversion with the user conversion
3412 /* The entire sequence is a user-conversion sequence. */
3413 std_seq->user_conv_p = true;
3418 /* Handle overload resolution for initializing an object of class type from
3419 an initializer list. First we look for a suitable constructor that
3420 takes a std::initializer_list; if we don't find one, we then look for a
3421 non-list constructor.
3423 Parameters are as for add_candidates, except that the arguments are in
3424 the form of a CONSTRUCTOR (the initializer list) rather than a VEC, and
3425 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3428 add_list_candidates (tree fns, tree first_arg,
3429 tree init_list, tree totype,
3430 tree explicit_targs, bool template_only,
3431 tree conversion_path, tree access_path,
3433 struct z_candidate **candidates)
3437 gcc_assert (*candidates == NULL);
3439 /* For list-initialization we consider explicit constructors, but
3440 give an error if one is selected. */
3441 flags &= ~LOOKUP_ONLYCONVERTING;
3442 /* And we don't allow narrowing conversions. We also use this flag to
3443 avoid the copy constructor call for copy-list-initialization. */
3444 flags |= LOOKUP_NO_NARROWING;
3446 /* Always use the default constructor if the list is empty (DR 990). */
3447 if (CONSTRUCTOR_NELTS (init_list) == 0
3448 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
3450 /* If the class has a list ctor, try passing the list as a single
3451 argument first, but only consider list ctors. */
3452 else if (TYPE_HAS_LIST_CTOR (totype))
3454 flags |= LOOKUP_LIST_ONLY;
3455 args = make_tree_vector_single (init_list);
3456 add_candidates (fns, first_arg, args, NULL_TREE,
3457 explicit_targs, template_only, conversion_path,
3458 access_path, flags, candidates);
3459 if (any_strictly_viable (*candidates))
3463 args = ctor_to_vec (init_list);
3465 /* We aren't looking for list-ctors anymore. */
3466 flags &= ~LOOKUP_LIST_ONLY;
3467 /* We allow more user-defined conversions within an init-list. */
3468 flags &= ~LOOKUP_NO_CONVERSION;
3469 /* But not for the copy ctor. */
3470 flags |= LOOKUP_NO_COPY_CTOR_CONVERSION;
3472 add_candidates (fns, first_arg, args, NULL_TREE,
3473 explicit_targs, template_only, conversion_path,
3474 access_path, flags, candidates);
3477 /* Returns the best overload candidate to perform the requested
3478 conversion. This function is used for three the overloading situations
3479 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3480 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
3481 per [dcl.init.ref], so we ignore temporary bindings. */
3483 static struct z_candidate *
3484 build_user_type_conversion_1 (tree totype, tree expr, int flags)
3486 struct z_candidate *candidates, *cand;
3487 tree fromtype = TREE_TYPE (expr);
3488 tree ctors = NULL_TREE;
3489 tree conv_fns = NULL_TREE;
3490 conversion *conv = NULL;
3491 tree first_arg = NULL_TREE;
3492 VEC(tree,gc) *args = NULL;
3496 /* We represent conversion within a hierarchy using RVALUE_CONV and
3497 BASE_CONV, as specified by [over.best.ics]; these become plain
3498 constructor calls, as specified in [dcl.init]. */
3499 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
3500 || !DERIVED_FROM_P (totype, fromtype));
3502 if (MAYBE_CLASS_TYPE_P (totype))
3503 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3504 creating a garbage BASELINK; constructors can't be inherited. */
3505 ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
3507 if (MAYBE_CLASS_TYPE_P (fromtype))
3509 tree to_nonref = non_reference (totype);
3510 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
3511 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
3512 && DERIVED_FROM_P (to_nonref, fromtype)))
3514 /* [class.conv.fct] A conversion function is never used to
3515 convert a (possibly cv-qualified) object to the (possibly
3516 cv-qualified) same object type (or a reference to it), to a
3517 (possibly cv-qualified) base class of that type (or a
3518 reference to it)... */
3521 conv_fns = lookup_conversions (fromtype);
3525 flags |= LOOKUP_NO_CONVERSION;
3526 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3527 flags |= LOOKUP_NO_NARROWING;
3529 /* It's OK to bind a temporary for converting constructor arguments, but
3530 not in converting the return value of a conversion operator. */
3531 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
3532 flags &= ~LOOKUP_NO_TEMP_BIND;
3536 int ctorflags = flags;
3538 first_arg = build_int_cst (build_pointer_type (totype), 0);
3540 /* We should never try to call the abstract or base constructor
3542 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3543 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3545 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3547 /* List-initialization. */
3548 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3549 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3550 ctorflags, &candidates);
3554 args = make_tree_vector_single (expr);
3555 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3556 TYPE_BINFO (totype), TYPE_BINFO (totype),
3557 ctorflags, &candidates);
3560 for (cand = candidates; cand; cand = cand->next)
3562 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3564 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3565 set, then this is copy-initialization. In that case, "The
3566 result of the call is then used to direct-initialize the
3567 object that is the destination of the copy-initialization."
3570 We represent this in the conversion sequence with an
3571 rvalue conversion, which means a constructor call. */
3572 if (TREE_CODE (totype) != REFERENCE_TYPE
3573 && !(convflags & LOOKUP_NO_TEMP_BIND))
3575 = build_conv (ck_rvalue, totype, cand->second_conv);
3580 first_arg = build_this (expr);
3582 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3584 tree conversion_path = TREE_PURPOSE (conv_fns);
3585 struct z_candidate *old_candidates;
3587 /* If we are called to convert to a reference type, we are trying to
3588 find a direct binding, so don't even consider temporaries. If
3589 we don't find a direct binding, the caller will try again to
3590 look for a temporary binding. */
3591 if (TREE_CODE (totype) == REFERENCE_TYPE)
3592 convflags |= LOOKUP_NO_TEMP_BIND;
3594 old_candidates = candidates;
3595 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3597 conversion_path, TYPE_BINFO (fromtype),
3598 flags, &candidates);
3600 for (cand = candidates; cand != old_candidates; cand = cand->next)
3602 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3604 = implicit_conversion (totype,
3607 /*c_cast_p=*/false, convflags);
3609 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3610 copy-initialization. In that case, "The result of the
3611 call is then used to direct-initialize the object that is
3612 the destination of the copy-initialization." [dcl.init]
3614 We represent this in the conversion sequence with an
3615 rvalue conversion, which means a constructor call. But
3616 don't add a second rvalue conversion if there's already
3617 one there. Which there really shouldn't be, but it's
3618 harmless since we'd add it here anyway. */
3619 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3620 && !(convflags & LOOKUP_NO_TEMP_BIND))
3621 ics = build_conv (ck_rvalue, totype, ics);
3623 cand->second_conv = ics;
3628 cand->reason = arg_conversion_rejection (NULL_TREE, -1,
3631 else if (DECL_NONCONVERTING_P (cand->fn)
3632 && ics->rank > cr_exact)
3634 /* 13.3.1.5: For direct-initialization, those explicit
3635 conversion functions that are not hidden within S and
3636 yield type T or a type that can be converted to type T
3637 with a qualification conversion (4.4) are also candidate
3640 cand->reason = explicit_conversion_rejection (rettype, totype);
3642 else if (cand->viable == 1 && ics->bad_p)
3646 = bad_arg_conversion_rejection (NULL_TREE, -1,
3652 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3656 release_tree_vector (args);
3660 cand = tourney (candidates);
3663 if (flags & LOOKUP_COMPLAIN)
3665 error ("conversion from %qT to %qT is ambiguous",
3667 print_z_candidates (location_of (expr), candidates);
3670 cand = candidates; /* any one will do */
3671 cand->second_conv = build_ambiguous_conv (totype, expr);
3672 cand->second_conv->user_conv_p = true;
3673 if (!any_strictly_viable (candidates))
3674 cand->second_conv->bad_p = true;
3675 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3676 ambiguous conversion is no worse than another user-defined
3682 /* Build the user conversion sequence. */
3685 (DECL_CONSTRUCTOR_P (cand->fn)
3686 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3687 build_identity_conv (TREE_TYPE (expr), expr));
3690 /* Remember that this was a list-initialization. */
3691 if (flags & LOOKUP_NO_NARROWING)
3692 conv->check_narrowing = true;
3694 /* Combine it with the second conversion sequence. */
3695 cand->second_conv = merge_conversion_sequences (conv,
3698 if (cand->viable == -1)
3699 cand->second_conv->bad_p = true;
3704 /* Wrapper for above. */
3707 build_user_type_conversion (tree totype, tree expr, int flags)
3709 struct z_candidate *cand;
3712 bool subtime = timevar_cond_start (TV_OVERLOAD);
3713 cand = build_user_type_conversion_1 (totype, expr, flags);
3717 if (cand->second_conv->kind == ck_ambig)
3718 ret = error_mark_node;
3721 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3722 ret = convert_from_reference (expr);
3728 timevar_cond_stop (TV_OVERLOAD, subtime);
3732 /* Subroutine of convert_nontype_argument.
3734 EXPR is an argument for a template non-type parameter of integral or
3735 enumeration type. Do any necessary conversions (that are permitted for
3736 non-type arguments) to convert it to the parameter type.
3738 If conversion is successful, returns the converted expression;
3739 otherwise, returns error_mark_node. */
3742 build_integral_nontype_arg_conv (tree type, tree expr, tsubst_flags_t complain)
3748 if (error_operand_p (expr))
3749 return error_mark_node;
3751 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
3753 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3754 p = conversion_obstack_alloc (0);
3756 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
3760 /* for a non-type template-parameter of integral or
3761 enumeration type, integral promotions (4.5) and integral
3762 conversions (4.7) are applied. */
3763 /* It should be sufficient to check the outermost conversion step, since
3764 there are no qualification conversions to integer type. */
3768 /* A conversion function is OK. If it isn't constexpr, we'll
3769 complain later that the argument isn't constant. */
3771 /* The lvalue-to-rvalue conversion is OK. */
3777 t = conv->u.next->type;
3778 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t))
3781 if (complain & tf_error)
3782 error ("conversion from %qT to %qT not considered for "
3783 "non-type template argument", t, type);
3784 /* and fall through. */
3792 expr = convert_like (conv, expr, complain);
3794 expr = error_mark_node;
3796 /* Free all the conversions we allocated. */
3797 obstack_free (&conversion_obstack, p);
3802 /* Do any initial processing on the arguments to a function call. */
3804 static VEC(tree,gc) *
3805 resolve_args (VEC(tree,gc) *args, tsubst_flags_t complain)
3810 FOR_EACH_VEC_ELT (tree, args, ix, arg)
3812 if (error_operand_p (arg))
3814 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3816 if (complain & tf_error)
3817 error ("invalid use of void expression");
3820 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3826 /* Perform overload resolution on FN, which is called with the ARGS.
3828 Return the candidate function selected by overload resolution, or
3829 NULL if the event that overload resolution failed. In the case
3830 that overload resolution fails, *CANDIDATES will be the set of
3831 candidates considered, and ANY_VIABLE_P will be set to true or
3832 false to indicate whether or not any of the candidates were
3835 The ARGS should already have gone through RESOLVE_ARGS before this
3836 function is called. */
3838 static struct z_candidate *
3839 perform_overload_resolution (tree fn,
3840 const VEC(tree,gc) *args,
3841 struct z_candidate **candidates,
3844 struct z_candidate *cand;
3845 tree explicit_targs;
3848 bool subtime = timevar_cond_start (TV_OVERLOAD);
3850 explicit_targs = NULL_TREE;
3854 *any_viable_p = true;
3857 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3858 || TREE_CODE (fn) == TEMPLATE_DECL
3859 || TREE_CODE (fn) == OVERLOAD
3860 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3862 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3864 explicit_targs = TREE_OPERAND (fn, 1);
3865 fn = TREE_OPERAND (fn, 0);
3869 /* Add the various candidate functions. */
3870 add_candidates (fn, NULL_TREE, args, NULL_TREE,
3871 explicit_targs, template_only,
3872 /*conversion_path=*/NULL_TREE,
3873 /*access_path=*/NULL_TREE,
3877 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3879 cand = tourney (*candidates);
3883 timevar_cond_stop (TV_OVERLOAD, subtime);
3887 /* Print an error message about being unable to build a call to FN with
3888 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
3889 be located; CANDIDATES is a possibly empty list of such
3893 print_error_for_call_failure (tree fn, VEC(tree,gc) *args, bool any_viable_p,
3894 struct z_candidate *candidates)
3896 tree name = DECL_NAME (OVL_CURRENT (fn));
3897 location_t loc = location_of (name);
3900 error_at (loc, "no matching function for call to %<%D(%A)%>",
3901 name, build_tree_list_vec (args));
3903 error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous",
3904 name, build_tree_list_vec (args));
3906 print_z_candidates (loc, candidates);
3909 /* Return an expression for a call to FN (a namespace-scope function,
3910 or a static member function) with the ARGS. This may change
3914 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3915 tsubst_flags_t complain)
3917 struct z_candidate *candidates, *cand;
3922 if (args != NULL && *args != NULL)
3924 *args = resolve_args (*args, complain);
3926 return error_mark_node;
3929 /* If this function was found without using argument dependent
3930 lookup, then we want to ignore any undeclared friend
3936 fn = remove_hidden_names (fn);
3939 if (complain & tf_error)
3940 print_error_for_call_failure (orig_fn, *args, false, NULL);
3941 return error_mark_node;
3945 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3946 p = conversion_obstack_alloc (0);
3948 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3952 if (complain & tf_error)
3954 if (!any_viable_p && candidates && ! candidates->next
3955 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
3956 return cp_build_function_call_vec (candidates->fn, args, complain);
3957 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3958 fn = TREE_OPERAND (fn, 0);
3959 print_error_for_call_failure (fn, *args, any_viable_p, candidates);
3961 result = error_mark_node;
3965 int flags = LOOKUP_NORMAL;
3966 /* If fn is template_id_expr, the call has explicit template arguments
3967 (e.g. func<int>(5)), communicate this info to build_over_call
3968 through flags so that later we can use it to decide whether to warn
3969 about peculiar null pointer conversion. */
3970 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3971 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
3972 result = build_over_call (cand, flags, complain);
3975 /* Free all the conversions we allocated. */
3976 obstack_free (&conversion_obstack, p);
3981 /* Build a call to a global operator new. FNNAME is the name of the
3982 operator (either "operator new" or "operator new[]") and ARGS are
3983 the arguments provided. This may change ARGS. *SIZE points to the
3984 total number of bytes required by the allocation, and is updated if
3985 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3986 be used. If this function determines that no cookie should be
3987 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3988 non-NULL, it will be set, upon return, to the allocation function
3992 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3993 tree *size, tree *cookie_size,
3997 struct z_candidate *candidates;
3998 struct z_candidate *cand;
4003 VEC_safe_insert (tree, gc, *args, 0, *size);
4004 *args = resolve_args (*args, tf_warning_or_error);
4006 return error_mark_node;
4012 If this lookup fails to find the name, or if the allocated type
4013 is not a class type, the allocation function's name is looked
4014 up in the global scope.
4016 we disregard block-scope declarations of "operator new". */
4017 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
4019 /* Figure out what function is being called. */
4020 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
4022 /* If no suitable function could be found, issue an error message
4026 print_error_for_call_failure (fns, *args, any_viable_p, candidates);
4027 return error_mark_node;
4030 /* If a cookie is required, add some extra space. Whether
4031 or not a cookie is required cannot be determined until
4032 after we know which function was called. */
4035 bool use_cookie = true;
4036 if (!abi_version_at_least (2))
4038 /* In G++ 3.2, the check was implemented incorrectly; it
4039 looked at the placement expression, rather than the
4040 type of the function. */
4041 if (VEC_length (tree, *args) == 2
4042 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
4050 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
4051 /* Skip the size_t parameter. */
4052 arg_types = TREE_CHAIN (arg_types);
4053 /* Check the remaining parameters (if any). */
4055 && TREE_CHAIN (arg_types) == void_list_node
4056 && same_type_p (TREE_VALUE (arg_types),
4060 /* If we need a cookie, adjust the number of bytes allocated. */
4063 /* Update the total size. */
4064 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
4065 /* Update the argument list to reflect the adjusted size. */
4066 VEC_replace (tree, *args, 0, *size);
4069 *cookie_size = NULL_TREE;
4072 /* Tell our caller which function we decided to call. */
4076 /* Build the CALL_EXPR. */
4077 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
4080 /* Build a new call to operator(). This may change ARGS. */
4083 build_op_call_1 (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
4085 struct z_candidate *candidates = 0, *cand;
4086 tree fns, convs, first_mem_arg = NULL_TREE;
4087 tree type = TREE_TYPE (obj);
4089 tree result = NULL_TREE;
4092 if (error_operand_p (obj))
4093 return error_mark_node;
4095 obj = prep_operand (obj);
4097 if (TYPE_PTRMEMFUNC_P (type))
4099 if (complain & tf_error)
4100 /* It's no good looking for an overloaded operator() on a
4101 pointer-to-member-function. */
4102 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
4103 return error_mark_node;
4106 if (TYPE_BINFO (type))
4108 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
4109 if (fns == error_mark_node)
4110 return error_mark_node;
4115 if (args != NULL && *args != NULL)
4117 *args = resolve_args (*args, complain);
4119 return error_mark_node;
4122 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4123 p = conversion_obstack_alloc (0);
4127 first_mem_arg = build_this (obj);
4129 add_candidates (BASELINK_FUNCTIONS (fns),
4130 first_mem_arg, *args, NULL_TREE,
4132 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
4133 LOOKUP_NORMAL, &candidates);
4136 convs = lookup_conversions (type);
4138 for (; convs; convs = TREE_CHAIN (convs))
4140 tree fns = TREE_VALUE (convs);
4141 tree totype = TREE_TYPE (convs);
4143 if ((TREE_CODE (totype) == POINTER_TYPE
4144 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
4145 || (TREE_CODE (totype) == REFERENCE_TYPE
4146 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
4147 || (TREE_CODE (totype) == REFERENCE_TYPE
4148 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
4149 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
4150 for (; fns; fns = OVL_NEXT (fns))
4152 tree fn = OVL_CURRENT (fns);
4154 if (DECL_NONCONVERTING_P (fn))
4157 if (TREE_CODE (fn) == TEMPLATE_DECL)
4158 add_template_conv_candidate
4159 (&candidates, fn, obj, NULL_TREE, *args, totype,
4160 /*access_path=*/NULL_TREE,
4161 /*conversion_path=*/NULL_TREE);
4163 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
4164 *args, /*conversion_path=*/NULL_TREE,
4165 /*access_path=*/NULL_TREE);
4169 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4172 if (complain & tf_error)
4174 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
4175 build_tree_list_vec (*args));
4176 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4178 result = error_mark_node;
4182 cand = tourney (candidates);
4185 if (complain & tf_error)
4187 error ("call of %<(%T) (%A)%> is ambiguous",
4188 TREE_TYPE (obj), build_tree_list_vec (*args));
4189 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4191 result = error_mark_node;
4193 /* Since cand->fn will be a type, not a function, for a conversion
4194 function, we must be careful not to unconditionally look at
4196 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
4197 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
4198 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4201 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
4203 obj = convert_from_reference (obj);
4204 result = cp_build_function_call_vec (obj, args, complain);
4208 /* Free all the conversions we allocated. */
4209 obstack_free (&conversion_obstack, p);
4214 /* Wrapper for above. */
4217 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
4220 bool subtime = timevar_cond_start (TV_OVERLOAD);
4221 ret = build_op_call_1 (obj, args, complain);
4222 timevar_cond_stop (TV_OVERLOAD, subtime);
4227 op_error (enum tree_code code, enum tree_code code2,
4228 tree arg1, tree arg2, tree arg3, bool match)
4232 if (code == MODIFY_EXPR)
4233 opname = assignment_operator_name_info[code2].name;
4235 opname = operator_name_info[code].name;
4241 error ("ambiguous overload for ternary %<operator?:%> "
4242 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4244 error ("no match for ternary %<operator?:%> "
4245 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4248 case POSTINCREMENT_EXPR:
4249 case POSTDECREMENT_EXPR:
4251 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
4252 opname, arg1, opname);
4254 error ("no match for %<operator%s%> in %<%E%s%>",
4255 opname, arg1, opname);
4260 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
4263 error ("no match for %<operator[]%> in %<%E[%E]%>",
4270 error ("ambiguous overload for %qs in %<%s %E%>",
4271 opname, opname, arg1);
4273 error ("no match for %qs in %<%s %E%>",
4274 opname, opname, arg1);
4280 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
4281 opname, arg1, opname, arg2);
4283 error ("no match for %<operator%s%> in %<%E %s %E%>",
4284 opname, arg1, opname, arg2);
4287 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
4288 opname, opname, arg1);
4290 error ("no match for %<operator%s%> in %<%s%E%>",
4291 opname, opname, arg1);
4296 /* Return the implicit conversion sequence that could be used to
4297 convert E1 to E2 in [expr.cond]. */
4300 conditional_conversion (tree e1, tree e2)
4302 tree t1 = non_reference (TREE_TYPE (e1));
4303 tree t2 = non_reference (TREE_TYPE (e2));
4309 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4310 implicitly converted (clause _conv_) to the type "lvalue reference to
4311 T2", subject to the constraint that in the conversion the
4312 reference must bind directly (_dcl.init.ref_) to an lvalue. */
4313 if (real_lvalue_p (e2))
4315 conv = implicit_conversion (build_reference_type (t2),
4319 LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND
4320 |LOOKUP_ONLYCONVERTING);
4327 If E1 and E2 have class type, and the underlying class types are
4328 the same or one is a base class of the other: E1 can be converted
4329 to match E2 if the class of T2 is the same type as, or a base
4330 class of, the class of T1, and the cv-qualification of T2 is the
4331 same cv-qualification as, or a greater cv-qualification than, the
4332 cv-qualification of T1. If the conversion is applied, E1 is
4333 changed to an rvalue of type T2 that still refers to the original
4334 source class object (or the appropriate subobject thereof). */
4335 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
4336 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
4338 if (good_base && at_least_as_qualified_p (t2, t1))
4340 conv = build_identity_conv (t1, e1);
4341 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
4342 TYPE_MAIN_VARIANT (t2)))
4343 conv = build_conv (ck_base, t2, conv);
4345 conv = build_conv (ck_rvalue, t2, conv);
4354 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4355 converted to the type that expression E2 would have if E2 were
4356 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4357 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
4361 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4362 arguments to the conditional expression. */
4365 build_conditional_expr_1 (tree arg1, tree arg2, tree arg3,
4366 tsubst_flags_t complain)
4370 tree result = NULL_TREE;
4371 tree result_type = NULL_TREE;
4372 bool lvalue_p = true;
4373 struct z_candidate *candidates = 0;
4374 struct z_candidate *cand;
4377 /* As a G++ extension, the second argument to the conditional can be
4378 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4379 c'.) If the second operand is omitted, make sure it is
4380 calculated only once. */
4383 if (complain & tf_error)
4384 pedwarn (input_location, OPT_pedantic,
4385 "ISO C++ forbids omitting the middle term of a ?: expression");
4387 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4388 if (real_lvalue_p (arg1))
4389 arg2 = arg1 = stabilize_reference (arg1);
4391 arg2 = arg1 = save_expr (arg1);
4396 The first expression is implicitly converted to bool (clause
4398 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
4401 /* If something has already gone wrong, just pass that fact up the
4403 if (error_operand_p (arg1)
4404 || error_operand_p (arg2)
4405 || error_operand_p (arg3))
4406 return error_mark_node;
4410 If either the second or the third operand has type (possibly
4411 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4412 array-to-pointer (_conv.array_), and function-to-pointer
4413 (_conv.func_) standard conversions are performed on the second
4414 and third operands. */
4415 arg2_type = unlowered_expr_type (arg2);
4416 arg3_type = unlowered_expr_type (arg3);
4417 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
4419 /* Do the conversions. We don't these for `void' type arguments
4420 since it can't have any effect and since decay_conversion
4421 does not handle that case gracefully. */
4422 if (!VOID_TYPE_P (arg2_type))
4423 arg2 = decay_conversion (arg2);
4424 if (!VOID_TYPE_P (arg3_type))
4425 arg3 = decay_conversion (arg3);
4426 arg2_type = TREE_TYPE (arg2);
4427 arg3_type = TREE_TYPE (arg3);
4431 One of the following shall hold:
4433 --The second or the third operand (but not both) is a
4434 throw-expression (_except.throw_); the result is of the
4435 type of the other and is an rvalue.
4437 --Both the second and the third operands have type void; the
4438 result is of type void and is an rvalue.
4440 We must avoid calling force_rvalue for expressions of type
4441 "void" because it will complain that their value is being
4443 if (TREE_CODE (arg2) == THROW_EXPR
4444 && TREE_CODE (arg3) != THROW_EXPR)
4446 if (!VOID_TYPE_P (arg3_type))
4448 arg3 = force_rvalue (arg3, complain);
4449 if (arg3 == error_mark_node)
4450 return error_mark_node;
4452 arg3_type = TREE_TYPE (arg3);
4453 result_type = arg3_type;
4455 else if (TREE_CODE (arg2) != THROW_EXPR
4456 && TREE_CODE (arg3) == THROW_EXPR)
4458 if (!VOID_TYPE_P (arg2_type))
4460 arg2 = force_rvalue (arg2, complain);
4461 if (arg2 == error_mark_node)
4462 return error_mark_node;
4464 arg2_type = TREE_TYPE (arg2);
4465 result_type = arg2_type;
4467 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
4468 result_type = void_type_node;
4471 if (complain & tf_error)
4473 if (VOID_TYPE_P (arg2_type))
4474 error ("second operand to the conditional operator "
4475 "is of type %<void%>, "
4476 "but the third operand is neither a throw-expression "
4477 "nor of type %<void%>");
4479 error ("third operand to the conditional operator "
4480 "is of type %<void%>, "
4481 "but the second operand is neither a throw-expression "
4482 "nor of type %<void%>");
4484 return error_mark_node;
4488 goto valid_operands;
4492 Otherwise, if the second and third operand have different types,
4493 and either has (possibly cv-qualified) class type, an attempt is
4494 made to convert each of those operands to the type of the other. */
4495 else if (!same_type_p (arg2_type, arg3_type)
4496 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4501 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4502 p = conversion_obstack_alloc (0);
4504 conv2 = conditional_conversion (arg2, arg3);
4505 conv3 = conditional_conversion (arg3, arg2);
4509 If both can be converted, or one can be converted but the
4510 conversion is ambiguous, the program is ill-formed. If
4511 neither can be converted, the operands are left unchanged and
4512 further checking is performed as described below. If exactly
4513 one conversion is possible, that conversion is applied to the
4514 chosen operand and the converted operand is used in place of
4515 the original operand for the remainder of this section. */
4516 if ((conv2 && !conv2->bad_p
4517 && conv3 && !conv3->bad_p)
4518 || (conv2 && conv2->kind == ck_ambig)
4519 || (conv3 && conv3->kind == ck_ambig))
4521 error ("operands to ?: have different types %qT and %qT",
4522 arg2_type, arg3_type);
4523 result = error_mark_node;
4525 else if (conv2 && (!conv2->bad_p || !conv3))
4527 arg2 = convert_like (conv2, arg2, complain);
4528 arg2 = convert_from_reference (arg2);
4529 arg2_type = TREE_TYPE (arg2);
4530 /* Even if CONV2 is a valid conversion, the result of the
4531 conversion may be invalid. For example, if ARG3 has type
4532 "volatile X", and X does not have a copy constructor
4533 accepting a "volatile X&", then even if ARG2 can be
4534 converted to X, the conversion will fail. */
4535 if (error_operand_p (arg2))
4536 result = error_mark_node;
4538 else if (conv3 && (!conv3->bad_p || !conv2))
4540 arg3 = convert_like (conv3, arg3, complain);
4541 arg3 = convert_from_reference (arg3);
4542 arg3_type = TREE_TYPE (arg3);
4543 if (error_operand_p (arg3))
4544 result = error_mark_node;
4547 /* Free all the conversions we allocated. */
4548 obstack_free (&conversion_obstack, p);
4553 /* If, after the conversion, both operands have class type,
4554 treat the cv-qualification of both operands as if it were the
4555 union of the cv-qualification of the operands.
4557 The standard is not clear about what to do in this
4558 circumstance. For example, if the first operand has type
4559 "const X" and the second operand has a user-defined
4560 conversion to "volatile X", what is the type of the second
4561 operand after this step? Making it be "const X" (matching
4562 the first operand) seems wrong, as that discards the
4563 qualification without actually performing a copy. Leaving it
4564 as "volatile X" seems wrong as that will result in the
4565 conditional expression failing altogether, even though,
4566 according to this step, the one operand could be converted to
4567 the type of the other. */
4568 if ((conv2 || conv3)
4569 && CLASS_TYPE_P (arg2_type)
4570 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
4571 arg2_type = arg3_type =
4572 cp_build_qualified_type (arg2_type,
4573 cp_type_quals (arg2_type)
4574 | cp_type_quals (arg3_type));
4579 If the second and third operands are lvalues and have the same
4580 type, the result is of that type and is an lvalue. */
4581 if (real_lvalue_p (arg2)
4582 && real_lvalue_p (arg3)
4583 && same_type_p (arg2_type, arg3_type))
4585 result_type = arg2_type;
4586 arg2 = mark_lvalue_use (arg2);
4587 arg3 = mark_lvalue_use (arg3);
4588 goto valid_operands;
4593 Otherwise, the result is an rvalue. If the second and third
4594 operand do not have the same type, and either has (possibly
4595 cv-qualified) class type, overload resolution is used to
4596 determine the conversions (if any) to be applied to the operands
4597 (_over.match.oper_, _over.built_). */
4599 if (!same_type_p (arg2_type, arg3_type)
4600 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4606 /* Rearrange the arguments so that add_builtin_candidate only has
4607 to know about two args. In build_builtin_candidate, the
4608 arguments are unscrambled. */
4612 add_builtin_candidates (&candidates,
4615 ansi_opname (COND_EXPR),
4621 If the overload resolution fails, the program is
4623 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4626 if (complain & tf_error)
4628 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4629 print_z_candidates (location_of (arg1), candidates);
4631 return error_mark_node;
4633 cand = tourney (candidates);
4636 if (complain & tf_error)
4638 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4639 print_z_candidates (location_of (arg1), candidates);
4641 return error_mark_node;
4646 Otherwise, the conversions thus determined are applied, and
4647 the converted operands are used in place of the original
4648 operands for the remainder of this section. */
4649 conv = cand->convs[0];
4650 arg1 = convert_like (conv, arg1, complain);
4651 conv = cand->convs[1];
4652 arg2 = convert_like (conv, arg2, complain);
4653 arg2_type = TREE_TYPE (arg2);
4654 conv = cand->convs[2];
4655 arg3 = convert_like (conv, arg3, complain);
4656 arg3_type = TREE_TYPE (arg3);
4661 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
4662 and function-to-pointer (_conv.func_) standard conversions are
4663 performed on the second and third operands.
4665 We need to force the lvalue-to-rvalue conversion here for class types,
4666 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
4667 that isn't wrapped with a TARGET_EXPR plays havoc with exception
4670 arg2 = force_rvalue (arg2, complain);
4671 if (!CLASS_TYPE_P (arg2_type))
4672 arg2_type = TREE_TYPE (arg2);
4674 arg3 = force_rvalue (arg3, complain);
4675 if (!CLASS_TYPE_P (arg3_type))
4676 arg3_type = TREE_TYPE (arg3);
4678 if (arg2 == error_mark_node || arg3 == error_mark_node)
4679 return error_mark_node;
4683 After those conversions, one of the following shall hold:
4685 --The second and third operands have the same type; the result is of
4687 if (same_type_p (arg2_type, arg3_type))
4688 result_type = arg2_type;
4691 --The second and third operands have arithmetic or enumeration
4692 type; the usual arithmetic conversions are performed to bring
4693 them to a common type, and the result is of that type. */
4694 else if ((ARITHMETIC_TYPE_P (arg2_type)
4695 || UNSCOPED_ENUM_P (arg2_type))
4696 && (ARITHMETIC_TYPE_P (arg3_type)
4697 || UNSCOPED_ENUM_P (arg3_type)))
4699 /* In this case, there is always a common type. */
4700 result_type = type_after_usual_arithmetic_conversions (arg2_type,
4702 do_warn_double_promotion (result_type, arg2_type, arg3_type,
4703 "implicit conversion from %qT to %qT to "
4704 "match other result of conditional",
4707 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
4708 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
4710 if (complain & tf_warning)
4712 "enumeral mismatch in conditional expression: %qT vs %qT",
4713 arg2_type, arg3_type);
4715 else if (extra_warnings
4716 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
4717 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
4718 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
4719 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
4721 if (complain & tf_warning)
4723 "enumeral and non-enumeral type in conditional expression");
4726 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4727 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4731 --The second and third operands have pointer type, or one has
4732 pointer type and the other is a null pointer constant; pointer
4733 conversions (_conv.ptr_) and qualification conversions
4734 (_conv.qual_) are performed to bring them to their composite
4735 pointer type (_expr.rel_). The result is of the composite
4738 --The second and third operands have pointer to member type, or
4739 one has pointer to member type and the other is a null pointer
4740 constant; pointer to member conversions (_conv.mem_) and
4741 qualification conversions (_conv.qual_) are performed to bring
4742 them to a common type, whose cv-qualification shall match the
4743 cv-qualification of either the second or the third operand.
4744 The result is of the common type. */
4745 else if ((null_ptr_cst_p (arg2)
4746 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
4747 || (null_ptr_cst_p (arg3)
4748 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
4749 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
4750 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
4751 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
4753 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
4754 arg3, CPO_CONDITIONAL_EXPR,
4756 if (result_type == error_mark_node)
4757 return error_mark_node;
4758 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4759 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4764 if (complain & tf_error)
4765 error ("operands to ?: have different types %qT and %qT",
4766 arg2_type, arg3_type);
4767 return error_mark_node;
4771 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4772 if (!cp_unevaluated_operand)
4773 /* Avoid folding within decltype (c++/42013) and noexcept. */
4774 result = fold_if_not_in_template (result);
4776 /* We can't use result_type below, as fold might have returned a
4781 /* Expand both sides into the same slot, hopefully the target of
4782 the ?: expression. We used to check for TARGET_EXPRs here,
4783 but now we sometimes wrap them in NOP_EXPRs so the test would
4785 if (CLASS_TYPE_P (TREE_TYPE (result)))
4786 result = get_target_expr (result);
4787 /* If this expression is an rvalue, but might be mistaken for an
4788 lvalue, we must add a NON_LVALUE_EXPR. */
4789 result = rvalue (result);
4795 /* Wrapper for above. */
4798 build_conditional_expr (tree arg1, tree arg2, tree arg3,
4799 tsubst_flags_t complain)
4802 bool subtime = timevar_cond_start (TV_OVERLOAD);
4803 ret = build_conditional_expr_1 (arg1, arg2, arg3, complain);
4804 timevar_cond_stop (TV_OVERLOAD, subtime);
4808 /* OPERAND is an operand to an expression. Perform necessary steps
4809 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4813 prep_operand (tree operand)
4817 if (CLASS_TYPE_P (TREE_TYPE (operand))
4818 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4819 /* Make sure the template type is instantiated now. */
4820 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4826 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4827 OVERLOAD) to the CANDIDATES, returning an updated list of
4828 CANDIDATES. The ARGS are the arguments provided to the call;
4829 if FIRST_ARG is non-null it is the implicit object argument,
4830 otherwise the first element of ARGS is used if needed. The
4831 EXPLICIT_TARGS are explicit template arguments provided.
4832 TEMPLATE_ONLY is true if only template functions should be
4833 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4834 add_function_candidate. */
4837 add_candidates (tree fns, tree first_arg, const VEC(tree,gc) *args,
4839 tree explicit_targs, bool template_only,
4840 tree conversion_path, tree access_path,
4842 struct z_candidate **candidates)
4845 const VEC(tree,gc) *non_static_args;
4846 bool check_list_ctor;
4847 bool check_converting;
4848 unification_kind_t strict;
4854 /* Precalculate special handling of constructors and conversion ops. */
4855 fn = OVL_CURRENT (fns);
4856 if (DECL_CONV_FN_P (fn))
4858 check_list_ctor = false;
4859 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4860 if (flags & LOOKUP_NO_CONVERSION)
4861 /* We're doing return_type(x). */
4862 strict = DEDUCE_CONV;
4864 /* We're doing x.operator return_type(). */
4865 strict = DEDUCE_EXACT;
4866 /* [over.match.funcs] For conversion functions, the function
4867 is considered to be a member of the class of the implicit
4868 object argument for the purpose of defining the type of
4869 the implicit object parameter. */
4870 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (first_arg)));
4874 if (DECL_CONSTRUCTOR_P (fn))
4876 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
4877 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4881 check_list_ctor = false;
4882 check_converting = false;
4884 strict = DEDUCE_CALL;
4885 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4889 non_static_args = args;
4891 /* Delay creating the implicit this parameter until it is needed. */
4892 non_static_args = NULL;
4894 for (; fns; fns = OVL_NEXT (fns))
4897 const VEC(tree,gc) *fn_args;
4899 fn = OVL_CURRENT (fns);
4901 if (check_converting && DECL_NONCONVERTING_P (fn))
4903 if (check_list_ctor && !is_list_ctor (fn))
4906 /* Figure out which set of arguments to use. */
4907 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4909 /* If this function is a non-static member and we didn't get an
4910 implicit object argument, move it out of args. */
4911 if (first_arg == NULL_TREE)
4915 VEC(tree,gc) *tempvec
4916 = VEC_alloc (tree, gc, VEC_length (tree, args) - 1);
4917 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4918 VEC_quick_push (tree, tempvec, arg);
4919 non_static_args = tempvec;
4920 first_arg = build_this (VEC_index (tree, args, 0));
4923 fn_first_arg = first_arg;
4924 fn_args = non_static_args;
4928 /* Otherwise, just use the list of arguments provided. */
4929 fn_first_arg = NULL_TREE;
4933 if (TREE_CODE (fn) == TEMPLATE_DECL)
4934 add_template_candidate (candidates,
4945 else if (!template_only)
4946 add_function_candidate (candidates,
4957 /* Even unsigned enum types promote to signed int. We don't want to
4958 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4959 original argument and ARG is the argument after any conversions
4960 have been applied. We set TREE_NO_WARNING if we have added a cast
4961 from an unsigned enum type to a signed integer type. */
4964 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4966 if (orig_arg != NULL_TREE
4969 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4970 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4971 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4972 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4973 TREE_NO_WARNING (arg) = 1;
4977 build_new_op_1 (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4978 tree *overload, tsubst_flags_t complain)
4980 tree orig_arg1 = arg1;
4981 tree orig_arg2 = arg2;
4982 tree orig_arg3 = arg3;
4983 struct z_candidate *candidates = 0, *cand;
4984 VEC(tree,gc) *arglist;
4987 tree result = NULL_TREE;
4988 bool result_valid_p = false;
4989 enum tree_code code2 = NOP_EXPR;
4990 enum tree_code code_orig_arg1 = ERROR_MARK;
4991 enum tree_code code_orig_arg2 = ERROR_MARK;
4997 if (error_operand_p (arg1)
4998 || error_operand_p (arg2)
4999 || error_operand_p (arg3))
5000 return error_mark_node;
5002 if (code == MODIFY_EXPR)
5004 code2 = TREE_CODE (arg3);
5006 fnname = ansi_assopname (code2);
5009 fnname = ansi_opname (code);
5011 arg1 = prep_operand (arg1);
5017 case VEC_DELETE_EXPR:
5019 /* Use build_op_new_call and build_op_delete_call instead. */
5023 /* Use build_op_call instead. */
5026 case TRUTH_ORIF_EXPR:
5027 case TRUTH_ANDIF_EXPR:
5028 case TRUTH_AND_EXPR:
5030 /* These are saved for the sake of warn_logical_operator. */
5031 code_orig_arg1 = TREE_CODE (arg1);
5032 code_orig_arg2 = TREE_CODE (arg2);
5038 arg2 = prep_operand (arg2);
5039 arg3 = prep_operand (arg3);
5041 if (code == COND_EXPR)
5042 /* Use build_conditional_expr instead. */
5044 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
5045 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
5048 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
5049 arg2 = integer_zero_node;
5051 arglist = VEC_alloc (tree, gc, 3);
5052 VEC_quick_push (tree, arglist, arg1);
5053 if (arg2 != NULL_TREE)
5054 VEC_quick_push (tree, arglist, arg2);
5055 if (arg3 != NULL_TREE)
5056 VEC_quick_push (tree, arglist, arg3);
5058 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5059 p = conversion_obstack_alloc (0);
5061 /* Add namespace-scope operators to the list of functions to
5063 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
5064 NULL_TREE, arglist, NULL_TREE,
5065 NULL_TREE, false, NULL_TREE, NULL_TREE,
5066 flags, &candidates);
5067 /* Add class-member operators to the candidate set. */
5068 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
5072 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
5073 if (fns == error_mark_node)
5075 result = error_mark_node;
5076 goto user_defined_result_ready;
5079 add_candidates (BASELINK_FUNCTIONS (fns),
5080 NULL_TREE, arglist, NULL_TREE,
5082 BASELINK_BINFO (fns),
5083 BASELINK_ACCESS_BINFO (fns),
5084 flags, &candidates);
5089 args[2] = NULL_TREE;
5091 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
5097 /* For these, the built-in candidates set is empty
5098 [over.match.oper]/3. We don't want non-strict matches
5099 because exact matches are always possible with built-in
5100 operators. The built-in candidate set for COMPONENT_REF
5101 would be empty too, but since there are no such built-in
5102 operators, we accept non-strict matches for them. */
5107 strict_p = pedantic;
5111 candidates = splice_viable (candidates, strict_p, &any_viable_p);
5116 case POSTINCREMENT_EXPR:
5117 case POSTDECREMENT_EXPR:
5118 /* Don't try anything fancy if we're not allowed to produce
5120 if (!(complain & tf_error))
5121 return error_mark_node;
5123 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5124 distinguish between prefix and postfix ++ and
5125 operator++() was used for both, so we allow this with
5127 if (flags & LOOKUP_COMPLAIN)
5129 const char *msg = (flag_permissive)
5130 ? G_("no %<%D(int)%> declared for postfix %qs,"
5131 " trying prefix operator instead")
5132 : G_("no %<%D(int)%> declared for postfix %qs");
5133 permerror (input_location, msg, fnname,
5134 operator_name_info[code].name);
5137 if (!flag_permissive)
5138 return error_mark_node;
5140 if (code == POSTINCREMENT_EXPR)
5141 code = PREINCREMENT_EXPR;
5143 code = PREDECREMENT_EXPR;
5144 result = build_new_op_1 (code, flags, arg1, NULL_TREE, NULL_TREE,
5145 overload, complain);
5148 /* The caller will deal with these. */
5153 result_valid_p = true;
5157 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5159 /* If one of the arguments of the operator represents
5160 an invalid use of member function pointer, try to report
5161 a meaningful error ... */
5162 if (invalid_nonstatic_memfn_p (arg1, tf_error)
5163 || invalid_nonstatic_memfn_p (arg2, tf_error)
5164 || invalid_nonstatic_memfn_p (arg3, tf_error))
5165 /* We displayed the error message. */;
5168 /* ... Otherwise, report the more generic
5169 "no matching operator found" error */
5170 op_error (code, code2, arg1, arg2, arg3, FALSE);
5171 print_z_candidates (input_location, candidates);
5174 result = error_mark_node;
5180 cand = tourney (candidates);
5183 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5185 op_error (code, code2, arg1, arg2, arg3, TRUE);
5186 print_z_candidates (input_location, candidates);
5188 result = error_mark_node;
5190 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
5193 *overload = cand->fn;
5195 if (resolve_args (arglist, complain) == NULL)
5196 result = error_mark_node;
5198 result = build_over_call (cand, LOOKUP_NORMAL, complain);
5202 /* Give any warnings we noticed during overload resolution. */
5203 if (cand->warnings && (complain & tf_warning))
5205 struct candidate_warning *w;
5206 for (w = cand->warnings; w; w = w->next)
5207 joust (cand, w->loser, 1);
5210 /* Check for comparison of different enum types. */
5219 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
5220 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
5221 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
5222 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
5223 && (complain & tf_warning))
5225 warning (OPT_Wenum_compare,
5226 "comparison between %q#T and %q#T",
5227 TREE_TYPE (arg1), TREE_TYPE (arg2));
5234 /* We need to strip any leading REF_BIND so that bitfields
5235 don't cause errors. This should not remove any important
5236 conversions, because builtins don't apply to class
5237 objects directly. */
5238 conv = cand->convs[0];
5239 if (conv->kind == ck_ref_bind)
5240 conv = conv->u.next;
5241 arg1 = convert_like (conv, arg1, complain);
5245 /* We need to call warn_logical_operator before
5246 converting arg2 to a boolean_type. */
5247 if (complain & tf_warning)
5248 warn_logical_operator (input_location, code, boolean_type_node,
5249 code_orig_arg1, arg1,
5250 code_orig_arg2, arg2);
5252 conv = cand->convs[1];
5253 if (conv->kind == ck_ref_bind)
5254 conv = conv->u.next;
5255 arg2 = convert_like (conv, arg2, complain);
5259 conv = cand->convs[2];
5260 if (conv->kind == ck_ref_bind)
5261 conv = conv->u.next;
5262 arg3 = convert_like (conv, arg3, complain);
5268 user_defined_result_ready:
5270 /* Free all the conversions we allocated. */
5271 obstack_free (&conversion_obstack, p);
5273 if (result || result_valid_p)
5277 avoid_sign_compare_warnings (orig_arg1, arg1);
5278 avoid_sign_compare_warnings (orig_arg2, arg2);
5279 avoid_sign_compare_warnings (orig_arg3, arg3);
5284 return cp_build_modify_expr (arg1, code2, arg2, complain);
5287 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
5289 case TRUTH_ANDIF_EXPR:
5290 case TRUTH_ORIF_EXPR:
5291 case TRUTH_AND_EXPR:
5293 warn_logical_operator (input_location, code, boolean_type_node,
5294 code_orig_arg1, arg1, code_orig_arg2, arg2);
5299 case TRUNC_DIV_EXPR:
5310 case TRUNC_MOD_EXPR:
5314 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
5316 case UNARY_PLUS_EXPR:
5319 case TRUTH_NOT_EXPR:
5320 case PREINCREMENT_EXPR:
5321 case POSTINCREMENT_EXPR:
5322 case PREDECREMENT_EXPR:
5323 case POSTDECREMENT_EXPR:
5326 return cp_build_unary_op (code, arg1, candidates != 0, complain);
5329 return cp_build_array_ref (input_location, arg1, arg2, complain);
5332 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
5336 /* The caller will deal with these. */
5348 /* Wrapper for above. */
5351 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
5352 tree *overload, tsubst_flags_t complain)
5355 bool subtime = timevar_cond_start (TV_OVERLOAD);
5356 ret = build_new_op_1 (code, flags, arg1, arg2, arg3, overload, complain);
5357 timevar_cond_stop (TV_OVERLOAD, subtime);
5361 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5362 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5365 non_placement_deallocation_fn_p (tree t)
5367 /* A template instance is never a usual deallocation function,
5368 regardless of its signature. */
5369 if (TREE_CODE (t) == TEMPLATE_DECL
5370 || primary_template_instantiation_p (t))
5373 /* If a class T has a member deallocation function named operator delete
5374 with exactly one parameter, then that function is a usual
5375 (non-placement) deallocation function. If class T does not declare
5376 such an operator delete but does declare a member deallocation
5377 function named operator delete with exactly two parameters, the second
5378 of which has type std::size_t (18.2), then this function is a usual
5379 deallocation function. */
5380 t = FUNCTION_ARG_CHAIN (t);
5381 if (t == void_list_node
5382 || (t && same_type_p (TREE_VALUE (t), size_type_node)
5383 && TREE_CHAIN (t) == void_list_node))
5388 /* Build a call to operator delete. This has to be handled very specially,
5389 because the restrictions on what signatures match are different from all
5390 other call instances. For a normal delete, only a delete taking (void *)
5391 or (void *, size_t) is accepted. For a placement delete, only an exact
5392 match with the placement new is accepted.
5394 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5395 ADDR is the pointer to be deleted.
5396 SIZE is the size of the memory block to be deleted.
5397 GLOBAL_P is true if the delete-expression should not consider
5398 class-specific delete operators.
5399 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5401 If this call to "operator delete" is being generated as part to
5402 deallocate memory allocated via a new-expression (as per [expr.new]
5403 which requires that if the initialization throws an exception then
5404 we call a deallocation function), then ALLOC_FN is the allocation
5408 build_op_delete_call (enum tree_code code, tree addr, tree size,
5409 bool global_p, tree placement,
5412 tree fn = NULL_TREE;
5413 tree fns, fnname, type, t;
5415 if (addr == error_mark_node)
5416 return error_mark_node;
5418 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
5420 fnname = ansi_opname (code);
5422 if (CLASS_TYPE_P (type)
5423 && COMPLETE_TYPE_P (complete_type (type))
5427 If the result of the lookup is ambiguous or inaccessible, or if
5428 the lookup selects a placement deallocation function, the
5429 program is ill-formed.
5431 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5433 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
5434 if (fns == error_mark_node)
5435 return error_mark_node;
5440 if (fns == NULL_TREE)
5441 fns = lookup_name_nonclass (fnname);
5443 /* Strip const and volatile from addr. */
5444 addr = cp_convert (ptr_type_node, addr);
5448 /* "A declaration of a placement deallocation function matches the
5449 declaration of a placement allocation function if it has the same
5450 number of parameters and, after parameter transformations (8.3.5),
5451 all parameter types except the first are identical."
5453 So we build up the function type we want and ask instantiate_type
5454 to get it for us. */
5455 t = FUNCTION_ARG_CHAIN (alloc_fn);
5456 t = tree_cons (NULL_TREE, ptr_type_node, t);
5457 t = build_function_type (void_type_node, t);
5459 fn = instantiate_type (t, fns, tf_none);
5460 if (fn == error_mark_node)
5463 if (BASELINK_P (fn))
5464 fn = BASELINK_FUNCTIONS (fn);
5466 /* "If the lookup finds the two-parameter form of a usual deallocation
5467 function (3.7.4.2) and that function, considered as a placement
5468 deallocation function, would have been selected as a match for the
5469 allocation function, the program is ill-formed." */
5470 if (non_placement_deallocation_fn_p (fn))
5472 /* But if the class has an operator delete (void *), then that is
5473 the usual deallocation function, so we shouldn't complain
5474 about using the operator delete (void *, size_t). */
5475 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5476 t; t = OVL_NEXT (t))
5478 tree elt = OVL_CURRENT (t);
5479 if (non_placement_deallocation_fn_p (elt)
5480 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
5483 permerror (0, "non-placement deallocation function %q+D", fn);
5484 permerror (input_location, "selected for placement delete");
5489 /* "Any non-placement deallocation function matches a non-placement
5490 allocation function. If the lookup finds a single matching
5491 deallocation function, that function will be called; otherwise, no
5492 deallocation function will be called." */
5493 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5494 t; t = OVL_NEXT (t))
5496 tree elt = OVL_CURRENT (t);
5497 if (non_placement_deallocation_fn_p (elt))
5500 /* "If a class T has a member deallocation function named
5501 operator delete with exactly one parameter, then that
5502 function is a usual (non-placement) deallocation
5503 function. If class T does not declare such an operator
5504 delete but does declare a member deallocation function named
5505 operator delete with exactly two parameters, the second of
5506 which has type std::size_t (18.2), then this function is a
5507 usual deallocation function."
5509 So (void*) beats (void*, size_t). */
5510 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
5515 /* If we have a matching function, call it. */
5518 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5520 /* If the FN is a member function, make sure that it is
5522 if (BASELINK_P (fns))
5523 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
5525 /* Core issue 901: It's ok to new a type with deleted delete. */
5526 if (DECL_DELETED_FN (fn) && alloc_fn)
5531 /* The placement args might not be suitable for overload
5532 resolution at this point, so build the call directly. */
5533 int nargs = call_expr_nargs (placement);
5534 tree *argarray = XALLOCAVEC (tree, nargs);
5537 for (i = 1; i < nargs; i++)
5538 argarray[i] = CALL_EXPR_ARG (placement, i);
5540 return build_cxx_call (fn, nargs, argarray);
5545 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
5546 VEC_quick_push (tree, args, addr);
5547 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
5548 VEC_quick_push (tree, args, size);
5549 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
5550 VEC_free (tree, gc, args);
5557 If no unambiguous matching deallocation function can be found,
5558 propagating the exception does not cause the object's memory to
5563 warning (0, "no corresponding deallocation function for %qD",
5568 error ("no suitable %<operator %s%> for %qT",
5569 operator_name_info[(int)code].name, type);
5570 return error_mark_node;
5573 /* If the current scope isn't allowed to access DECL along
5574 BASETYPE_PATH, give an error. The most derived class in
5575 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
5576 the declaration to use in the error diagnostic. */
5579 enforce_access (tree basetype_path, tree decl, tree diag_decl)
5581 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
5583 if (!accessible_p (basetype_path, decl, true))
5585 if (TREE_PRIVATE (decl))
5586 error ("%q+#D is private", diag_decl);
5587 else if (TREE_PROTECTED (decl))
5588 error ("%q+#D is protected", diag_decl);
5590 error ("%q+#D is inaccessible", diag_decl);
5591 error ("within this context");
5598 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
5599 bitwise or of LOOKUP_* values. If any errors are warnings are
5600 generated, set *DIAGNOSTIC_FN to "error" or "warning",
5601 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
5605 build_temp (tree expr, tree type, int flags,
5606 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
5611 savew = warningcount, savee = errorcount;
5612 args = make_tree_vector_single (expr);
5613 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
5614 &args, type, flags, complain);
5615 release_tree_vector (args);
5616 if (warningcount > savew)
5617 *diagnostic_kind = DK_WARNING;
5618 else if (errorcount > savee)
5619 *diagnostic_kind = DK_ERROR;
5621 *diagnostic_kind = DK_UNSPECIFIED;
5625 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
5626 EXPR is implicitly converted to type TOTYPE.
5627 FN and ARGNUM are used for diagnostics. */
5630 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
5632 tree t = non_reference (totype);
5634 /* Issue warnings about peculiar, but valid, uses of NULL. */
5635 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
5638 warning_at (input_location, OPT_Wconversion_null,
5639 "passing NULL to non-pointer argument %P of %qD",
5642 warning_at (input_location, OPT_Wconversion_null,
5643 "converting to non-pointer type %qT from NULL", t);
5646 /* Issue warnings if "false" is converted to a NULL pointer */
5647 else if (expr == boolean_false_node && POINTER_TYPE_P (t))
5650 warning_at (input_location, OPT_Wconversion_null,
5651 "converting %<false%> to pointer type for argument %P "
5652 "of %qD", argnum, fn);
5654 warning_at (input_location, OPT_Wconversion_null,
5655 "converting %<false%> to pointer type %qT", t);
5659 /* Perform the conversions in CONVS on the expression EXPR. FN and
5660 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
5661 indicates the `this' argument of a method. INNER is nonzero when
5662 being called to continue a conversion chain. It is negative when a
5663 reference binding will be applied, positive otherwise. If
5664 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
5665 conversions will be emitted if appropriate. If C_CAST_P is true,
5666 this conversion is coming from a C-style cast; in that case,
5667 conversions to inaccessible bases are permitted. */
5670 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
5671 int inner, bool issue_conversion_warnings,
5672 bool c_cast_p, tsubst_flags_t complain)
5674 tree totype = convs->type;
5675 diagnostic_t diag_kind;
5678 if (convs->bad_p && !(complain & tf_error))
5679 return error_mark_node;
5682 && convs->kind != ck_user
5683 && convs->kind != ck_list
5684 && convs->kind != ck_ambig
5685 && convs->kind != ck_ref_bind
5686 && convs->kind != ck_rvalue
5687 && convs->kind != ck_base)
5689 conversion *t = convs;
5691 /* Give a helpful error if this is bad because of excess braces. */
5692 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5693 && SCALAR_TYPE_P (totype)
5694 && CONSTRUCTOR_NELTS (expr) > 0
5695 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
5696 permerror (input_location, "too many braces around initializer for %qT", totype);
5698 for (; t; t = convs->u.next)
5700 if (t->kind == ck_user && t->cand->reason)
5702 permerror (input_location, "invalid user-defined conversion "
5703 "from %qT to %qT", TREE_TYPE (expr), totype);
5704 print_z_candidate ("candidate is:", t->cand);
5705 expr = convert_like_real (t, expr, fn, argnum, 1,
5706 /*issue_conversion_warnings=*/false,
5709 return cp_convert (totype, expr);
5711 else if (t->kind == ck_user || !t->bad_p)
5713 expr = convert_like_real (t, expr, fn, argnum, 1,
5714 /*issue_conversion_warnings=*/false,
5719 else if (t->kind == ck_ambig)
5720 return convert_like_real (t, expr, fn, argnum, 1,
5721 /*issue_conversion_warnings=*/false,
5724 else if (t->kind == ck_identity)
5728 permerror (input_location, "invalid conversion from %qT to %qT",
5729 TREE_TYPE (expr), totype);
5731 permerror (DECL_SOURCE_LOCATION (fn),
5732 " initializing argument %P of %qD", argnum, fn);
5734 return cp_convert (totype, expr);
5737 if (issue_conversion_warnings && (complain & tf_warning))
5738 conversion_null_warnings (totype, expr, fn, argnum);
5740 switch (convs->kind)
5744 struct z_candidate *cand = convs->cand;
5745 tree convfn = cand->fn;
5748 /* If we're initializing from {}, it's value-initialization. */
5749 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5750 && CONSTRUCTOR_NELTS (expr) == 0
5751 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
5753 expr = build_value_init (totype, complain);
5754 expr = get_target_expr_sfinae (expr, complain);
5755 if (expr != error_mark_node)
5756 TARGET_EXPR_LIST_INIT_P (expr) = true;
5760 expr = mark_rvalue_use (expr);
5762 /* When converting from an init list we consider explicit
5763 constructors, but actually trying to call one is an error. */
5764 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
5765 /* Unless we're calling it for value-initialization from an
5766 empty list, since that is handled separately in 8.5.4. */
5767 && cand->num_convs > 0)
5769 error ("converting to %qT from initializer list would use "
5770 "explicit constructor %qD", totype, convfn);
5773 /* Set user_conv_p on the argument conversions, so rvalue/base
5774 handling knows not to allow any more UDCs. */
5775 for (i = 0; i < cand->num_convs; ++i)
5776 cand->convs[i]->user_conv_p = true;
5778 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
5780 /* If this is a constructor or a function returning an aggr type,
5781 we need to build up a TARGET_EXPR. */
5782 if (DECL_CONSTRUCTOR_P (convfn))
5784 expr = build_cplus_new (totype, expr, complain);
5786 /* Remember that this was list-initialization. */
5787 if (convs->check_narrowing && expr != error_mark_node)
5788 TARGET_EXPR_LIST_INIT_P (expr) = true;
5794 expr = mark_rvalue_use (expr);
5795 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
5797 int nelts = CONSTRUCTOR_NELTS (expr);
5799 expr = build_value_init (totype, complain);
5800 else if (nelts == 1)
5801 expr = CONSTRUCTOR_ELT (expr, 0)->value;
5806 if (type_unknown_p (expr))
5807 expr = instantiate_type (totype, expr, complain);
5808 /* Convert a constant to its underlying value, unless we are
5809 about to bind it to a reference, in which case we need to
5810 leave it as an lvalue. */
5813 expr = decl_constant_value (expr);
5814 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
5815 /* If __null has been converted to an integer type, we do not
5816 want to warn about uses of EXPR as an integer, rather than
5818 expr = build_int_cst (totype, 0);
5822 /* We leave bad_p off ck_ambig because overload resolution considers
5823 it valid, it just fails when we try to perform it. So we need to
5824 check complain here, too. */
5825 if (complain & tf_error)
5827 /* Call build_user_type_conversion again for the error. */
5828 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL);
5830 error (" initializing argument %P of %q+D", argnum, fn);
5832 return error_mark_node;
5836 /* Conversion to std::initializer_list<T>. */
5837 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
5838 tree new_ctor = build_constructor (init_list_type_node, NULL);
5839 unsigned len = CONSTRUCTOR_NELTS (expr);
5840 tree array, val, field;
5841 VEC(constructor_elt,gc) *vec = NULL;
5844 /* Convert all the elements. */
5845 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
5847 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
5848 1, false, false, complain);
5849 if (sub == error_mark_node)
5851 if (!BRACE_ENCLOSED_INITIALIZER_P (val))
5852 check_narrowing (TREE_TYPE (sub), val);
5853 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
5854 if (!TREE_CONSTANT (sub))
5855 TREE_CONSTANT (new_ctor) = false;
5857 /* Build up the array. */
5858 elttype = cp_build_qualified_type
5859 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
5860 array = build_array_of_n_type (elttype, len);
5861 array = finish_compound_literal (array, new_ctor, complain);
5863 /* Build up the initializer_list object. */
5864 totype = complete_type (totype);
5865 field = next_initializable_field (TYPE_FIELDS (totype));
5866 CONSTRUCTOR_APPEND_ELT (vec, field, decay_conversion (array));
5867 field = next_initializable_field (DECL_CHAIN (field));
5868 CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len));
5869 new_ctor = build_constructor (totype, vec);
5870 return get_target_expr (new_ctor);
5874 if (TREE_CODE (totype) == COMPLEX_TYPE)
5876 tree real = CONSTRUCTOR_ELT (expr, 0)->value;
5877 tree imag = CONSTRUCTOR_ELT (expr, 1)->value;
5878 real = perform_implicit_conversion (TREE_TYPE (totype),
5880 imag = perform_implicit_conversion (TREE_TYPE (totype),
5882 expr = build2 (COMPLEX_EXPR, totype, real, imag);
5883 return fold_if_not_in_template (expr);
5885 return get_target_expr (digest_init (totype, expr, complain));
5891 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5892 convs->kind == ck_ref_bind ? -1 : 1,
5893 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5896 if (expr == error_mark_node)
5897 return error_mark_node;
5899 switch (convs->kind)
5902 expr = decay_conversion (expr);
5903 if (! MAYBE_CLASS_TYPE_P (totype))
5905 /* Else fall through. */
5907 if (convs->kind == ck_base && !convs->need_temporary_p)
5909 /* We are going to bind a reference directly to a base-class
5910 subobject of EXPR. */
5911 /* Build an expression for `*((base*) &expr)'. */
5912 expr = cp_build_addr_expr (expr, complain);
5913 expr = convert_to_base (expr, build_pointer_type (totype),
5914 !c_cast_p, /*nonnull=*/true, complain);
5915 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5919 /* Copy-initialization where the cv-unqualified version of the source
5920 type is the same class as, or a derived class of, the class of the
5921 destination [is treated as direct-initialization]. [dcl.init] */
5922 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5923 if (convs->user_conv_p)
5924 /* This conversion is being done in the context of a user-defined
5925 conversion (i.e. the second step of copy-initialization), so
5926 don't allow any more. */
5927 flags |= LOOKUP_NO_CONVERSION;
5928 if (convs->rvaluedness_matches_p)
5929 flags |= LOOKUP_PREFER_RVALUE;
5930 if (TREE_CODE (expr) == TARGET_EXPR
5931 && TARGET_EXPR_LIST_INIT_P (expr))
5932 /* Copy-list-initialization doesn't actually involve a copy. */
5934 expr = build_temp (expr, totype, flags, &diag_kind, complain);
5935 if (diag_kind && fn && complain)
5936 emit_diagnostic (diag_kind, DECL_SOURCE_LOCATION (fn), 0,
5937 " initializing argument %P of %qD", argnum, fn);
5938 return build_cplus_new (totype, expr, complain);
5942 tree ref_type = totype;
5944 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
5945 && real_lvalue_p (expr))
5947 error ("cannot bind %qT lvalue to %qT",
5948 TREE_TYPE (expr), totype);
5950 error (" initializing argument %P of %q+D", argnum, fn);
5951 return error_mark_node;
5954 /* If necessary, create a temporary.
5956 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5957 that need temporaries, even when their types are reference
5958 compatible with the type of reference being bound, so the
5959 upcoming call to cp_build_addr_expr doesn't fail. */
5960 if (convs->need_temporary_p
5961 || TREE_CODE (expr) == CONSTRUCTOR
5962 || TREE_CODE (expr) == VA_ARG_EXPR)
5964 /* Otherwise, a temporary of type "cv1 T1" is created and
5965 initialized from the initializer expression using the rules
5966 for a non-reference copy-initialization (8.5). */
5968 tree type = TREE_TYPE (ref_type);
5969 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5971 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5972 (type, convs->u.next->type));
5973 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
5974 && !TYPE_REF_IS_RVALUE (ref_type))
5976 /* If the reference is volatile or non-const, we
5977 cannot create a temporary. */
5978 if (lvalue & clk_bitfield)
5979 error ("cannot bind bitfield %qE to %qT",
5981 else if (lvalue & clk_packed)
5982 error ("cannot bind packed field %qE to %qT",
5985 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5986 return error_mark_node;
5988 /* If the source is a packed field, and we must use a copy
5989 constructor, then building the target expr will require
5990 binding the field to the reference parameter to the
5991 copy constructor, and we'll end up with an infinite
5992 loop. If we can use a bitwise copy, then we'll be
5994 if ((lvalue & clk_packed)
5995 && CLASS_TYPE_P (type)
5996 && type_has_nontrivial_copy_init (type))
5998 error ("cannot bind packed field %qE to %qT",
6000 return error_mark_node;
6002 if (lvalue & clk_bitfield)
6004 expr = convert_bitfield_to_declared_type (expr);
6005 expr = fold_convert (type, expr);
6007 expr = build_target_expr_with_type (expr, type, complain);
6010 /* Take the address of the thing to which we will bind the
6012 expr = cp_build_addr_expr (expr, complain);
6013 if (expr == error_mark_node)
6014 return error_mark_node;
6016 /* Convert it to a pointer to the type referred to by the
6017 reference. This will adjust the pointer if a derived to
6018 base conversion is being performed. */
6019 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
6021 /* Convert the pointer to the desired reference type. */
6022 return build_nop (ref_type, expr);
6026 return decay_conversion (expr);
6029 /* Warn about deprecated conversion if appropriate. */
6030 string_conv_p (totype, expr, 1);
6035 expr = convert_to_base (expr, totype, !c_cast_p,
6036 /*nonnull=*/false, complain);
6037 return build_nop (totype, expr);
6040 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
6041 c_cast_p, complain);
6047 if (convs->check_narrowing)
6048 check_narrowing (totype, expr);
6050 if (issue_conversion_warnings && (complain & tf_warning))
6051 expr = convert_and_check (totype, expr);
6053 expr = convert (totype, expr);
6058 /* ARG is being passed to a varargs function. Perform any conversions
6059 required. Return the converted value. */
6062 convert_arg_to_ellipsis (tree arg)
6068 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6069 standard conversions are performed. */
6070 arg = decay_conversion (arg);
6071 arg_type = TREE_TYPE (arg);
6074 If the argument has integral or enumeration type that is subject
6075 to the integral promotions (_conv.prom_), or a floating point
6076 type that is subject to the floating point promotion
6077 (_conv.fpprom_), the value of the argument is converted to the
6078 promoted type before the call. */
6079 if (TREE_CODE (arg_type) == REAL_TYPE
6080 && (TYPE_PRECISION (arg_type)
6081 < TYPE_PRECISION (double_type_node))
6082 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
6084 if (warn_double_promotion && !c_inhibit_evaluation_warnings)
6085 warning (OPT_Wdouble_promotion,
6086 "implicit conversion from %qT to %qT when passing "
6087 "argument to function",
6088 arg_type, double_type_node);
6089 arg = convert_to_real (double_type_node, arg);
6091 else if (NULLPTR_TYPE_P (arg_type))
6092 arg = null_pointer_node;
6093 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
6095 if (SCOPED_ENUM_P (arg_type) && !abi_version_at_least (6))
6097 warning (OPT_Wabi, "scoped enum %qT will not promote to an "
6098 "integral type in a future version of GCC", arg_type);
6099 arg = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg);
6101 arg = perform_integral_promotions (arg);
6104 arg = require_complete_type (arg);
6105 arg_type = TREE_TYPE (arg);
6107 if (arg != error_mark_node
6108 /* In a template (or ill-formed code), we can have an incomplete type
6109 even after require_complete_type, in which case we don't know
6110 whether it has trivial copy or not. */
6111 && COMPLETE_TYPE_P (arg_type))
6113 /* Build up a real lvalue-to-rvalue conversion in case the
6114 copy constructor is trivial but not callable. */
6115 if (!cp_unevaluated_operand && CLASS_TYPE_P (arg_type))
6116 force_rvalue (arg, tf_warning_or_error);
6118 /* [expr.call] 5.2.2/7:
6119 Passing a potentially-evaluated argument of class type (Clause 9)
6120 with a non-trivial copy constructor or a non-trivial destructor
6121 with no corresponding parameter is conditionally-supported, with
6122 implementation-defined semantics.
6124 We used to just warn here and do a bitwise copy, but now
6125 cp_expr_size will abort if we try to do that.
6127 If the call appears in the context of a sizeof expression,
6128 it is not potentially-evaluated. */
6129 if (cp_unevaluated_operand == 0
6130 && (type_has_nontrivial_copy_init (arg_type)
6131 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
6132 error ("cannot pass objects of non-trivially-copyable "
6133 "type %q#T through %<...%>", arg_type);
6139 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6142 build_x_va_arg (tree expr, tree type)
6144 if (processing_template_decl)
6145 return build_min (VA_ARG_EXPR, type, expr);
6147 type = complete_type_or_else (type, NULL_TREE);
6149 if (expr == error_mark_node || !type)
6150 return error_mark_node;
6152 expr = mark_lvalue_use (expr);
6154 if (type_has_nontrivial_copy_init (type)
6155 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
6156 || TREE_CODE (type) == REFERENCE_TYPE)
6158 /* Remove reference types so we don't ICE later on. */
6159 tree type1 = non_reference (type);
6160 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
6161 error ("cannot receive objects of non-trivially-copyable type %q#T "
6162 "through %<...%>; ", type);
6163 expr = convert (build_pointer_type (type1), null_node);
6164 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
6168 return build_va_arg (input_location, expr, type);
6171 /* TYPE has been given to va_arg. Apply the default conversions which
6172 would have happened when passed via ellipsis. Return the promoted
6173 type, or the passed type if there is no change. */
6176 cxx_type_promotes_to (tree type)
6180 /* Perform the array-to-pointer and function-to-pointer
6182 type = type_decays_to (type);
6184 promote = type_promotes_to (type);
6185 if (same_type_p (type, promote))
6191 /* ARG is a default argument expression being passed to a parameter of
6192 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6193 zero-based argument number. Do any required conversions. Return
6194 the converted value. */
6196 static GTY(()) VEC(tree,gc) *default_arg_context;
6198 push_defarg_context (tree fn)
6199 { VEC_safe_push (tree, gc, default_arg_context, fn); }
6201 pop_defarg_context (void)
6202 { VEC_pop (tree, default_arg_context); }
6205 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
6210 /* See through clones. */
6211 fn = DECL_ORIGIN (fn);
6213 /* Detect recursion. */
6214 FOR_EACH_VEC_ELT (tree, default_arg_context, i, t)
6217 error ("recursive evaluation of default argument for %q#D", fn);
6218 return error_mark_node;
6221 /* If the ARG is an unparsed default argument expression, the
6222 conversion cannot be performed. */
6223 if (TREE_CODE (arg) == DEFAULT_ARG)
6225 error ("call to %qD uses the default argument for parameter %P, which "
6226 "is not yet defined", fn, parmnum);
6227 return error_mark_node;
6230 push_defarg_context (fn);
6232 if (fn && DECL_TEMPLATE_INFO (fn))
6233 arg = tsubst_default_argument (fn, type, arg);
6239 The names in the expression are bound, and the semantic
6240 constraints are checked, at the point where the default
6241 expressions appears.
6243 we must not perform access checks here. */
6244 push_deferring_access_checks (dk_no_check);
6245 arg = break_out_target_exprs (arg);
6246 if (TREE_CODE (arg) == CONSTRUCTOR)
6248 arg = digest_init (type, arg, tf_warning_or_error);
6249 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6250 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6251 tf_warning_or_error);
6255 /* We must make a copy of ARG, in case subsequent processing
6256 alters any part of it. For example, during gimplification a
6257 cast of the form (T) &X::f (where "f" is a member function)
6258 will lead to replacing the PTRMEM_CST for &X::f with a
6259 VAR_DECL. We can avoid the copy for constants, since they
6260 are never modified in place. */
6261 if (!CONSTANT_CLASS_P (arg))
6262 arg = unshare_expr (arg);
6263 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6264 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6265 tf_warning_or_error);
6266 arg = convert_for_arg_passing (type, arg);
6268 pop_deferring_access_checks();
6270 pop_defarg_context ();
6275 /* Returns the type which will really be used for passing an argument of
6279 type_passed_as (tree type)
6281 /* Pass classes with copy ctors by invisible reference. */
6282 if (TREE_ADDRESSABLE (type))
6284 type = build_reference_type (type);
6285 /* There are no other pointers to this temporary. */
6286 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
6288 else if (targetm.calls.promote_prototypes (type)
6289 && INTEGRAL_TYPE_P (type)
6290 && COMPLETE_TYPE_P (type)
6291 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6292 TYPE_SIZE (integer_type_node)))
6293 type = integer_type_node;
6298 /* Actually perform the appropriate conversion. */
6301 convert_for_arg_passing (tree type, tree val)
6305 /* If VAL is a bitfield, then -- since it has already been converted
6306 to TYPE -- it cannot have a precision greater than TYPE.
6308 If it has a smaller precision, we must widen it here. For
6309 example, passing "int f:3;" to a function expecting an "int" will
6310 not result in any conversion before this point.
6312 If the precision is the same we must not risk widening. For
6313 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6314 often have type "int", even though the C++ type for the field is
6315 "long long". If the value is being passed to a function
6316 expecting an "int", then no conversions will be required. But,
6317 if we call convert_bitfield_to_declared_type, the bitfield will
6318 be converted to "long long". */
6319 bitfield_type = is_bitfield_expr_with_lowered_type (val);
6321 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
6322 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
6324 if (val == error_mark_node)
6326 /* Pass classes with copy ctors by invisible reference. */
6327 else if (TREE_ADDRESSABLE (type))
6328 val = build1 (ADDR_EXPR, build_reference_type (type), val);
6329 else if (targetm.calls.promote_prototypes (type)
6330 && INTEGRAL_TYPE_P (type)
6331 && COMPLETE_TYPE_P (type)
6332 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6333 TYPE_SIZE (integer_type_node)))
6334 val = perform_integral_promotions (val);
6335 if (warn_missing_format_attribute)
6337 tree rhstype = TREE_TYPE (val);
6338 const enum tree_code coder = TREE_CODE (rhstype);
6339 const enum tree_code codel = TREE_CODE (type);
6340 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6342 && check_missing_format_attribute (type, rhstype))
6343 warning (OPT_Wmissing_format_attribute,
6344 "argument of function call might be a candidate for a format attribute");
6349 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6350 which no conversions at all should be done. This is true for some
6351 builtins which don't act like normal functions. */
6354 magic_varargs_p (tree fn)
6356 if (DECL_BUILT_IN (fn))
6357 switch (DECL_FUNCTION_CODE (fn))
6359 case BUILT_IN_CLASSIFY_TYPE:
6360 case BUILT_IN_CONSTANT_P:
6361 case BUILT_IN_NEXT_ARG:
6362 case BUILT_IN_VA_START:
6366 return lookup_attribute ("type generic",
6367 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
6373 /* Subroutine of the various build_*_call functions. Overload resolution
6374 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
6375 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
6376 bitmask of various LOOKUP_* flags which apply to the call itself. */
6379 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
6382 const VEC(tree,gc) *args = cand->args;
6383 tree first_arg = cand->first_arg;
6384 conversion **convs = cand->convs;
6386 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
6391 unsigned int arg_index = 0;
6395 bool already_used = false;
6397 /* In a template, there is no need to perform all of the work that
6398 is normally done. We are only interested in the type of the call
6399 expression, i.e., the return type of the function. Any semantic
6400 errors will be deferred until the template is instantiated. */
6401 if (processing_template_decl)
6405 const tree *argarray;
6408 return_type = TREE_TYPE (TREE_TYPE (fn));
6409 nargs = VEC_length (tree, args);
6410 if (first_arg == NULL_TREE)
6411 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
6419 alcarray = XALLOCAVEC (tree, nargs);
6420 alcarray[0] = first_arg;
6421 FOR_EACH_VEC_ELT (tree, args, ix, arg)
6422 alcarray[ix + 1] = arg;
6423 argarray = alcarray;
6425 expr = build_call_array_loc (input_location,
6426 return_type, build_addr_func (fn), nargs,
6428 if (TREE_THIS_VOLATILE (fn) && cfun)
6429 current_function_returns_abnormally = 1;
6430 return convert_from_reference (expr);
6433 /* Give any warnings we noticed during overload resolution. */
6434 if (cand->warnings && (complain & tf_warning))
6436 struct candidate_warning *w;
6437 for (w = cand->warnings; w; w = w->next)
6438 joust (cand, w->loser, 1);
6441 /* Make =delete work with SFINAE. */
6442 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
6443 return error_mark_node;
6445 if (DECL_FUNCTION_MEMBER_P (fn))
6448 /* If FN is a template function, two cases must be considered.
6453 template <class T> void f();
6455 template <class T> struct B {
6459 struct C : A, B<int> {
6461 using B<int>::g; // #2
6464 In case #1 where `A::f' is a member template, DECL_ACCESS is
6465 recorded in the primary template but not in its specialization.
6466 We check access of FN using its primary template.
6468 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
6469 because it is a member of class template B, DECL_ACCESS is
6470 recorded in the specialization `B<int>::g'. We cannot use its
6471 primary template because `B<T>::g' and `B<int>::g' may have
6472 different access. */
6473 if (DECL_TEMPLATE_INFO (fn)
6474 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
6475 access_fn = DECL_TI_TEMPLATE (fn);
6478 if (flags & LOOKUP_SPECULATIVE)
6480 if (!speculative_access_check (cand->access_path, access_fn, fn,
6481 !!(flags & LOOKUP_COMPLAIN)))
6482 return error_mark_node;
6485 perform_or_defer_access_check (cand->access_path, access_fn, fn);
6488 /* If we're checking for implicit delete, don't bother with argument
6490 if (flags & LOOKUP_SPECULATIVE)
6492 if (DECL_DELETED_FN (fn))
6494 if (flags & LOOKUP_COMPLAIN)
6496 return error_mark_node;
6498 if (cand->viable == 1)
6500 else if (!(flags & LOOKUP_COMPLAIN))
6501 /* Reject bad conversions now. */
6502 return error_mark_node;
6503 /* else continue to get conversion error. */
6506 /* Find maximum size of vector to hold converted arguments. */
6507 parmlen = list_length (parm);
6508 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
6509 if (parmlen > nargs)
6511 argarray = XALLOCAVEC (tree, nargs);
6513 /* The implicit parameters to a constructor are not considered by overload
6514 resolution, and must be of the proper type. */
6515 if (DECL_CONSTRUCTOR_P (fn))
6517 if (first_arg != NULL_TREE)
6519 argarray[j++] = first_arg;
6520 first_arg = NULL_TREE;
6524 argarray[j++] = VEC_index (tree, args, arg_index);
6527 parm = TREE_CHAIN (parm);
6528 /* We should never try to call the abstract constructor. */
6529 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
6531 if (DECL_HAS_VTT_PARM_P (fn))
6533 argarray[j++] = VEC_index (tree, args, arg_index);
6535 parm = TREE_CHAIN (parm);
6538 /* Bypass access control for 'this' parameter. */
6539 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6541 tree parmtype = TREE_VALUE (parm);
6542 tree arg = (first_arg != NULL_TREE
6544 : VEC_index (tree, args, arg_index));
6545 tree argtype = TREE_TYPE (arg);
6549 if (convs[i]->bad_p)
6551 if (complain & tf_error)
6552 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
6553 TREE_TYPE (argtype), fn);
6555 return error_mark_node;
6558 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
6559 X is called for an object that is not of type X, or of a type
6560 derived from X, the behavior is undefined.
6562 So we can assume that anything passed as 'this' is non-null, and
6563 optimize accordingly. */
6564 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
6565 /* Convert to the base in which the function was declared. */
6566 gcc_assert (cand->conversion_path != NULL_TREE);
6567 converted_arg = build_base_path (PLUS_EXPR,
6569 cand->conversion_path,
6571 /* Check that the base class is accessible. */
6572 if (!accessible_base_p (TREE_TYPE (argtype),
6573 BINFO_TYPE (cand->conversion_path), true))
6574 error ("%qT is not an accessible base of %qT",
6575 BINFO_TYPE (cand->conversion_path),
6576 TREE_TYPE (argtype));
6577 /* If fn was found by a using declaration, the conversion path
6578 will be to the derived class, not the base declaring fn. We
6579 must convert from derived to base. */
6580 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
6581 TREE_TYPE (parmtype), ba_unique, NULL);
6582 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
6585 argarray[j++] = converted_arg;
6586 parm = TREE_CHAIN (parm);
6587 if (first_arg != NULL_TREE)
6588 first_arg = NULL_TREE;
6595 gcc_assert (first_arg == NULL_TREE);
6596 for (; arg_index < VEC_length (tree, args) && parm;
6597 parm = TREE_CHAIN (parm), ++arg_index, ++i)
6599 tree type = TREE_VALUE (parm);
6600 tree arg = VEC_index (tree, args, arg_index);
6601 bool conversion_warning = true;
6605 /* If the argument is NULL and used to (implicitly) instantiate a
6606 template function (and bind one of the template arguments to
6607 the type of 'long int'), we don't want to warn about passing NULL
6608 to non-pointer argument.
6609 For example, if we have this template function:
6611 template<typename T> void func(T x) {}
6613 we want to warn (when -Wconversion is enabled) in this case:
6619 but not in this case:
6625 if (arg == null_node
6626 && DECL_TEMPLATE_INFO (fn)
6627 && cand->template_decl
6628 && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS))
6629 conversion_warning = false;
6631 /* Warn about initializer_list deduction that isn't currently in the
6633 if (cxx_dialect > cxx98
6634 && flag_deduce_init_list
6635 && cand->template_decl
6636 && is_std_init_list (non_reference (type))
6637 && BRACE_ENCLOSED_INITIALIZER_P (arg))
6639 tree tmpl = TI_TEMPLATE (cand->template_decl);
6640 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
6641 tree patparm = get_pattern_parm (realparm, tmpl);
6642 tree pattype = TREE_TYPE (patparm);
6643 if (PACK_EXPANSION_P (pattype))
6644 pattype = PACK_EXPANSION_PATTERN (pattype);
6645 pattype = non_reference (pattype);
6647 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
6648 && (cand->explicit_targs == NULL_TREE
6649 || (TREE_VEC_LENGTH (cand->explicit_targs)
6650 <= TEMPLATE_TYPE_IDX (pattype))))
6652 pedwarn (input_location, 0, "deducing %qT as %qT",
6653 non_reference (TREE_TYPE (patparm)),
6654 non_reference (type));
6655 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
6656 pedwarn (input_location, 0,
6657 " (you can disable this with -fno-deduce-init-list)");
6661 val = convert_like_with_context (conv, arg, fn, i-is_method,
6664 : complain & (~tf_warning));
6666 val = convert_for_arg_passing (type, val);
6667 if (val == error_mark_node)
6668 return error_mark_node;
6670 argarray[j++] = val;
6673 /* Default arguments */
6674 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
6675 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
6676 TREE_PURPOSE (parm),
6679 for (; arg_index < VEC_length (tree, args); ++arg_index)
6681 tree a = VEC_index (tree, args, arg_index);
6682 if (magic_varargs_p (fn))
6683 /* Do no conversions for magic varargs. */
6684 a = mark_type_use (a);
6686 a = convert_arg_to_ellipsis (a);
6690 gcc_assert (j <= nargs);
6693 check_function_arguments (TREE_TYPE (fn), nargs, argarray);
6695 /* Avoid actually calling copy constructors and copy assignment operators,
6698 if (! flag_elide_constructors)
6699 /* Do things the hard way. */;
6700 else if (cand->num_convs == 1
6701 && (DECL_COPY_CONSTRUCTOR_P (fn)
6702 || DECL_MOVE_CONSTRUCTOR_P (fn)))
6705 tree arg = argarray[num_artificial_parms_for (fn)];
6707 bool trivial = trivial_fn_p (fn);
6709 /* Pull out the real argument, disregarding const-correctness. */
6711 while (CONVERT_EXPR_P (targ)
6712 || TREE_CODE (targ) == NON_LVALUE_EXPR)
6713 targ = TREE_OPERAND (targ, 0);
6714 if (TREE_CODE (targ) == ADDR_EXPR)
6716 targ = TREE_OPERAND (targ, 0);
6717 if (!same_type_ignoring_top_level_qualifiers_p
6718 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
6727 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6729 /* [class.copy]: the copy constructor is implicitly defined even if
6730 the implementation elided its use. */
6731 if (!trivial || DECL_DELETED_FN (fn))
6734 already_used = true;
6737 /* If we're creating a temp and we already have one, don't create a
6738 new one. If we're not creating a temp but we get one, use
6739 INIT_EXPR to collapse the temp into our target. Otherwise, if the
6740 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
6741 temp or an INIT_EXPR otherwise. */
6743 if (integer_zerop (fa))
6745 if (TREE_CODE (arg) == TARGET_EXPR)
6748 return force_target_expr (DECL_CONTEXT (fn), arg, complain);
6750 else if (TREE_CODE (arg) == TARGET_EXPR || trivial)
6752 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
6755 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
6759 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
6760 && trivial_fn_p (fn)
6761 && !DECL_DELETED_FN (fn))
6763 tree to = stabilize_reference
6764 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
6765 tree type = TREE_TYPE (to);
6766 tree as_base = CLASSTYPE_AS_BASE (type);
6767 tree arg = argarray[1];
6769 if (is_really_empty_class (type))
6771 /* Avoid copying empty classes. */
6772 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
6773 TREE_NO_WARNING (val) = 1;
6774 val = build2 (COMPOUND_EXPR, type, val, to);
6775 TREE_NO_WARNING (val) = 1;
6777 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
6779 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6780 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
6784 /* We must only copy the non-tail padding parts. */
6786 tree array_type, alias_set;
6788 arg2 = TYPE_SIZE_UNIT (as_base);
6789 arg0 = cp_build_addr_expr (to, complain);
6791 array_type = build_array_type (char_type_node,
6793 (size_binop (MINUS_EXPR,
6794 arg2, size_int (1))));
6795 alias_set = build_int_cst (build_pointer_type (type), 0);
6796 t = build2 (MODIFY_EXPR, void_type_node,
6797 build2 (MEM_REF, array_type, arg0, alias_set),
6798 build2 (MEM_REF, array_type, arg, alias_set));
6799 val = build2 (COMPOUND_EXPR, TREE_TYPE (to), t, to);
6800 TREE_NO_WARNING (val) = 1;
6805 else if (DECL_DESTRUCTOR_P (fn)
6806 && trivial_fn_p (fn)
6807 && !DECL_DELETED_FN (fn))
6808 return fold_convert (void_type_node, argarray[0]);
6809 /* FIXME handle trivial default constructor, too. */
6814 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
6817 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
6820 gcc_assert (binfo && binfo != error_mark_node);
6822 /* Warn about deprecated virtual functions now, since we're about
6823 to throw away the decl. */
6824 if (TREE_DEPRECATED (fn))
6825 warn_deprecated_use (fn, NULL_TREE);
6827 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
6828 if (TREE_SIDE_EFFECTS (argarray[0]))
6829 argarray[0] = save_expr (argarray[0]);
6830 t = build_pointer_type (TREE_TYPE (fn));
6831 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
6832 fn = build_java_interface_fn_ref (fn, argarray[0]);
6834 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
6838 fn = build_addr_func (fn);
6840 return build_cxx_call (fn, nargs, argarray);
6843 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
6844 This function performs no overload resolution, conversion, or other
6845 high-level operations. */
6848 build_cxx_call (tree fn, int nargs, tree *argarray)
6852 /* Remember roughly where this call is. */
6853 location_t loc = EXPR_LOC_OR_HERE (fn);
6854 fn = build_call_a (fn, nargs, argarray);
6855 SET_EXPR_LOCATION (fn, loc);
6857 /* If this call might throw an exception, note that fact. */
6858 fndecl = get_callee_fndecl (fn);
6860 /* Check that arguments to builtin functions match the expectations. */
6862 && DECL_BUILT_IN (fndecl)
6863 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6864 && !check_builtin_function_arguments (fndecl, nargs, argarray))
6865 return error_mark_node;
6867 /* Some built-in function calls will be evaluated at compile-time in
6869 fn = fold_if_not_in_template (fn);
6871 if (VOID_TYPE_P (TREE_TYPE (fn)))
6874 fn = require_complete_type (fn);
6875 if (fn == error_mark_node)
6876 return error_mark_node;
6878 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
6879 fn = build_cplus_new (TREE_TYPE (fn), fn, tf_warning_or_error);
6880 return convert_from_reference (fn);
6883 static GTY(()) tree java_iface_lookup_fn;
6885 /* Make an expression which yields the address of the Java interface
6886 method FN. This is achieved by generating a call to libjava's
6887 _Jv_LookupInterfaceMethodIdx(). */
6890 build_java_interface_fn_ref (tree fn, tree instance)
6892 tree lookup_fn, method, idx;
6893 tree klass_ref, iface, iface_ref;
6896 if (!java_iface_lookup_fn)
6898 tree ftype = build_function_type_list (ptr_type_node,
6899 ptr_type_node, ptr_type_node,
6900 java_int_type_node, NULL_TREE);
6901 java_iface_lookup_fn
6902 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
6903 0, NOT_BUILT_IN, NULL, NULL_TREE);
6906 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
6907 This is the first entry in the vtable. */
6908 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
6909 tf_warning_or_error),
6912 /* Get the java.lang.Class pointer for the interface being called. */
6913 iface = DECL_CONTEXT (fn);
6914 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
6915 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
6916 || DECL_CONTEXT (iface_ref) != iface)
6918 error ("could not find class$ field in java interface type %qT",
6920 return error_mark_node;
6922 iface_ref = build_address (iface_ref);
6923 iface_ref = convert (build_pointer_type (iface), iface_ref);
6925 /* Determine the itable index of FN. */
6927 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
6929 if (!DECL_VIRTUAL_P (method))
6935 idx = build_int_cst (NULL_TREE, i);
6937 lookup_fn = build1 (ADDR_EXPR,
6938 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
6939 java_iface_lookup_fn);
6940 return build_call_nary (ptr_type_node, lookup_fn,
6941 3, klass_ref, iface_ref, idx);
6944 /* Returns the value to use for the in-charge parameter when making a
6945 call to a function with the indicated NAME.
6947 FIXME:Can't we find a neater way to do this mapping? */
6950 in_charge_arg_for_name (tree name)
6952 if (name == base_ctor_identifier
6953 || name == base_dtor_identifier)
6954 return integer_zero_node;
6955 else if (name == complete_ctor_identifier)
6956 return integer_one_node;
6957 else if (name == complete_dtor_identifier)
6958 return integer_two_node;
6959 else if (name == deleting_dtor_identifier)
6960 return integer_three_node;
6962 /* This function should only be called with one of the names listed
6968 /* Build a call to a constructor, destructor, or an assignment
6969 operator for INSTANCE, an expression with class type. NAME
6970 indicates the special member function to call; *ARGS are the
6971 arguments. ARGS may be NULL. This may change ARGS. BINFO
6972 indicates the base of INSTANCE that is to be passed as the `this'
6973 parameter to the member function called.
6975 FLAGS are the LOOKUP_* flags to use when processing the call.
6977 If NAME indicates a complete object constructor, INSTANCE may be
6978 NULL_TREE. In this case, the caller will call build_cplus_new to
6979 store the newly constructed object into a VAR_DECL. */
6982 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6983 tree binfo, int flags, tsubst_flags_t complain)
6986 /* The type of the subobject to be constructed or destroyed. */
6988 VEC(tree,gc) *allocated = NULL;
6991 gcc_assert (name == complete_ctor_identifier
6992 || name == base_ctor_identifier
6993 || name == complete_dtor_identifier
6994 || name == base_dtor_identifier
6995 || name == deleting_dtor_identifier
6996 || name == ansi_assopname (NOP_EXPR));
6999 /* Resolve the name. */
7000 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
7001 return error_mark_node;
7003 binfo = TYPE_BINFO (binfo);
7006 gcc_assert (binfo != NULL_TREE);
7008 class_type = BINFO_TYPE (binfo);
7010 /* Handle the special case where INSTANCE is NULL_TREE. */
7011 if (name == complete_ctor_identifier && !instance)
7013 instance = build_int_cst (build_pointer_type (class_type), 0);
7014 instance = build1 (INDIRECT_REF, class_type, instance);
7018 if (name == complete_dtor_identifier
7019 || name == base_dtor_identifier
7020 || name == deleting_dtor_identifier)
7021 gcc_assert (args == NULL || VEC_empty (tree, *args));
7023 /* Convert to the base class, if necessary. */
7024 if (!same_type_ignoring_top_level_qualifiers_p
7025 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
7027 if (name != ansi_assopname (NOP_EXPR))
7028 /* For constructors and destructors, either the base is
7029 non-virtual, or it is virtual but we are doing the
7030 conversion from a constructor or destructor for the
7031 complete object. In either case, we can convert
7033 instance = convert_to_base_statically (instance, binfo);
7035 /* However, for assignment operators, we must convert
7036 dynamically if the base is virtual. */
7037 instance = build_base_path (PLUS_EXPR, instance,
7038 binfo, /*nonnull=*/1);
7042 gcc_assert (instance != NULL_TREE);
7044 fns = lookup_fnfields (binfo, name, 1);
7046 /* When making a call to a constructor or destructor for a subobject
7047 that uses virtual base classes, pass down a pointer to a VTT for
7049 if ((name == base_ctor_identifier
7050 || name == base_dtor_identifier)
7051 && CLASSTYPE_VBASECLASSES (class_type))
7056 /* If the current function is a complete object constructor
7057 or destructor, then we fetch the VTT directly.
7058 Otherwise, we look it up using the VTT we were given. */
7059 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
7060 vtt = decay_conversion (vtt);
7061 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
7062 build2 (EQ_EXPR, boolean_type_node,
7063 current_in_charge_parm, integer_zero_node),
7066 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
7067 sub_vtt = fold_build_pointer_plus (vtt, BINFO_SUBVTT_INDEX (binfo));
7071 allocated = make_tree_vector ();
7075 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
7078 ret = build_new_method_call (instance, fns, args,
7079 TYPE_BINFO (BINFO_TYPE (binfo)),
7083 if (allocated != NULL)
7084 release_tree_vector (allocated);
7089 /* Return the NAME, as a C string. The NAME indicates a function that
7090 is a member of TYPE. *FREE_P is set to true if the caller must
7091 free the memory returned.
7093 Rather than go through all of this, we should simply set the names
7094 of constructors and destructors appropriately, and dispense with
7095 ctor_identifier, dtor_identifier, etc. */
7098 name_as_c_string (tree name, tree type, bool *free_p)
7102 /* Assume that we will not allocate memory. */
7104 /* Constructors and destructors are special. */
7105 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7108 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
7109 /* For a destructor, add the '~'. */
7110 if (name == complete_dtor_identifier
7111 || name == base_dtor_identifier
7112 || name == deleting_dtor_identifier)
7114 pretty_name = concat ("~", pretty_name, NULL);
7115 /* Remember that we need to free the memory allocated. */
7119 else if (IDENTIFIER_TYPENAME_P (name))
7121 pretty_name = concat ("operator ",
7122 type_as_string_translate (TREE_TYPE (name),
7123 TFF_PLAIN_IDENTIFIER),
7125 /* Remember that we need to free the memory allocated. */
7129 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
7134 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
7135 be set, upon return, to the function called. ARGS may be NULL.
7136 This may change ARGS. */
7139 build_new_method_call_1 (tree instance, tree fns, VEC(tree,gc) **args,
7140 tree conversion_path, int flags,
7141 tree *fn_p, tsubst_flags_t complain)
7143 struct z_candidate *candidates = 0, *cand;
7144 tree explicit_targs = NULL_TREE;
7145 tree basetype = NULL_TREE;
7148 tree first_mem_arg = NULL_TREE;
7151 bool skip_first_for_error;
7152 VEC(tree,gc) *user_args;
7155 int template_only = 0;
7159 VEC(tree,gc) *orig_args = NULL;
7162 gcc_assert (instance != NULL_TREE);
7164 /* We don't know what function we're going to call, yet. */
7168 if (error_operand_p (instance)
7169 || !fns || error_operand_p (fns))
7170 return error_mark_node;
7172 if (!BASELINK_P (fns))
7174 if (complain & tf_error)
7175 error ("call to non-function %qD", fns);
7176 return error_mark_node;
7179 orig_instance = instance;
7182 /* Dismantle the baselink to collect all the information we need. */
7183 if (!conversion_path)
7184 conversion_path = BASELINK_BINFO (fns);
7185 access_binfo = BASELINK_ACCESS_BINFO (fns);
7186 optype = BASELINK_OPTYPE (fns);
7187 fns = BASELINK_FUNCTIONS (fns);
7188 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7190 explicit_targs = TREE_OPERAND (fns, 1);
7191 fns = TREE_OPERAND (fns, 0);
7194 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
7195 || TREE_CODE (fns) == TEMPLATE_DECL
7196 || TREE_CODE (fns) == OVERLOAD);
7197 fn = get_first_fn (fns);
7198 name = DECL_NAME (fn);
7200 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
7201 gcc_assert (CLASS_TYPE_P (basetype));
7203 if (processing_template_decl)
7205 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
7206 instance = build_non_dependent_expr (instance);
7208 make_args_non_dependent (*args);
7211 user_args = args == NULL ? NULL : *args;
7212 /* Under DR 147 A::A() is an invalid constructor call,
7213 not a functional cast. */
7214 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
7216 if (! (complain & tf_error))
7217 return error_mark_node;
7219 permerror (input_location,
7220 "cannot call constructor %<%T::%D%> directly",
7222 permerror (input_location, " for a function-style cast, remove the "
7223 "redundant %<::%D%>", name);
7224 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
7229 /* Figure out whether to skip the first argument for the error
7230 message we will display to users if an error occurs. We don't
7231 want to display any compiler-generated arguments. The "this"
7232 pointer hasn't been added yet. However, we must remove the VTT
7233 pointer if this is a call to a base-class constructor or
7235 skip_first_for_error = false;
7236 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7238 /* Callers should explicitly indicate whether they want to construct
7239 the complete object or just the part without virtual bases. */
7240 gcc_assert (name != ctor_identifier);
7241 /* Similarly for destructors. */
7242 gcc_assert (name != dtor_identifier);
7243 /* Remove the VTT pointer, if present. */
7244 if ((name == base_ctor_identifier || name == base_dtor_identifier)
7245 && CLASSTYPE_VBASECLASSES (basetype))
7246 skip_first_for_error = true;
7249 /* Process the argument list. */
7250 if (args != NULL && *args != NULL)
7252 *args = resolve_args (*args, complain);
7254 return error_mark_node;
7257 instance_ptr = build_this (instance);
7259 /* It's OK to call destructors and constructors on cv-qualified objects.
7260 Therefore, convert the INSTANCE_PTR to the unqualified type, if
7262 if (DECL_DESTRUCTOR_P (fn)
7263 || DECL_CONSTRUCTOR_P (fn))
7265 tree type = build_pointer_type (basetype);
7266 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
7267 instance_ptr = build_nop (type, instance_ptr);
7269 if (DECL_DESTRUCTOR_P (fn))
7270 name = complete_dtor_identifier;
7272 first_mem_arg = instance_ptr;
7274 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7275 p = conversion_obstack_alloc (0);
7277 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
7278 initializer, not T({ }). */
7279 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
7280 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
7281 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0)))
7283 tree init_list = VEC_index (tree, *args, 0);
7285 gcc_assert (VEC_length (tree, *args) == 1
7286 && !(flags & LOOKUP_ONLYCONVERTING));
7288 /* If the initializer list has no elements and T is a class type with
7289 a default constructor, the object is value-initialized. Handle
7290 this here so we don't need to handle it wherever we use
7291 build_special_member_call. */
7292 if (CONSTRUCTOR_NELTS (init_list) == 0
7293 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
7294 && !processing_template_decl)
7296 tree ob, init = build_value_init (basetype, complain);
7297 if (integer_zerop (instance_ptr))
7298 return get_target_expr_sfinae (init, complain);
7299 ob = build_fold_indirect_ref (instance_ptr);
7300 init = build2 (INIT_EXPR, TREE_TYPE (ob), ob, init);
7301 TREE_SIDE_EFFECTS (init) = true;
7305 add_list_candidates (fns, first_mem_arg, init_list,
7306 basetype, explicit_targs, template_only,
7307 conversion_path, access_binfo, flags, &candidates);
7311 add_candidates (fns, first_mem_arg, user_args, optype,
7312 explicit_targs, template_only, conversion_path,
7313 access_binfo, flags, &candidates);
7315 any_viable_p = false;
7316 candidates = splice_viable (candidates, pedantic, &any_viable_p);
7320 if (complain & tf_error)
7322 if (!COMPLETE_OR_OPEN_TYPE_P (basetype))
7323 cxx_incomplete_type_error (instance_ptr, basetype);
7325 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
7326 basetype, optype, build_tree_list_vec (user_args),
7327 TREE_TYPE (TREE_TYPE (instance_ptr)));
7334 pretty_name = name_as_c_string (name, basetype, &free_p);
7335 arglist = build_tree_list_vec (user_args);
7336 if (skip_first_for_error)
7337 arglist = TREE_CHAIN (arglist);
7338 error ("no matching function for call to %<%T::%s(%A)%#V%>",
7339 basetype, pretty_name, arglist,
7340 TREE_TYPE (TREE_TYPE (instance_ptr)));
7344 print_z_candidates (location_of (name), candidates);
7346 call = error_mark_node;
7350 cand = tourney (candidates);
7357 if (complain & tf_error)
7359 pretty_name = name_as_c_string (name, basetype, &free_p);
7360 arglist = build_tree_list_vec (user_args);
7361 if (skip_first_for_error)
7362 arglist = TREE_CHAIN (arglist);
7363 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
7365 print_z_candidates (location_of (name), candidates);
7369 call = error_mark_node;
7375 if (!(flags & LOOKUP_NONVIRTUAL)
7376 && DECL_PURE_VIRTUAL_P (fn)
7377 && instance == current_class_ref
7378 && (DECL_CONSTRUCTOR_P (current_function_decl)
7379 || DECL_DESTRUCTOR_P (current_function_decl))
7380 && (complain & tf_warning))
7381 /* This is not an error, it is runtime undefined
7383 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
7384 "pure virtual %q#D called from constructor"
7385 : "pure virtual %q#D called from destructor"),
7388 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
7389 && is_dummy_object (instance_ptr))
7391 if (complain & tf_error)
7392 error ("cannot call member function %qD without object",
7394 call = error_mark_node;
7398 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
7399 && resolves_to_fixed_type_p (instance, 0))
7400 flags |= LOOKUP_NONVIRTUAL;
7402 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
7403 /* Now we know what function is being called. */
7406 /* Build the actual CALL_EXPR. */
7407 call = build_over_call (cand, flags, complain);
7408 /* In an expression of the form `a->f()' where `f' turns
7409 out to be a static member function, `a' is
7410 none-the-less evaluated. */
7411 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
7412 && !is_dummy_object (instance_ptr)
7413 && TREE_SIDE_EFFECTS (instance_ptr))
7414 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
7415 instance_ptr, call);
7416 else if (call != error_mark_node
7417 && DECL_DESTRUCTOR_P (cand->fn)
7418 && !VOID_TYPE_P (TREE_TYPE (call)))
7419 /* An explicit call of the form "x->~X()" has type
7420 "void". However, on platforms where destructors
7421 return "this" (i.e., those where
7422 targetm.cxx.cdtor_returns_this is true), such calls
7423 will appear to have a return value of pointer type
7424 to the low-level call machinery. We do not want to
7425 change the low-level machinery, since we want to be
7426 able to optimize "delete f()" on such platforms as
7427 "operator delete(~X(f()))" (rather than generating
7428 "t = f(), ~X(t), operator delete (t)"). */
7429 call = build_nop (void_type_node, call);
7434 if (processing_template_decl && call != error_mark_node)
7436 bool cast_to_void = false;
7438 if (TREE_CODE (call) == COMPOUND_EXPR)
7439 call = TREE_OPERAND (call, 1);
7440 else if (TREE_CODE (call) == NOP_EXPR)
7442 cast_to_void = true;
7443 call = TREE_OPERAND (call, 0);
7445 if (TREE_CODE (call) == INDIRECT_REF)
7446 call = TREE_OPERAND (call, 0);
7447 call = (build_min_non_dep_call_vec
7449 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
7450 orig_instance, orig_fns, NULL_TREE),
7452 call = convert_from_reference (call);
7454 call = build_nop (void_type_node, call);
7457 /* Free all the conversions we allocated. */
7458 obstack_free (&conversion_obstack, p);
7460 if (orig_args != NULL)
7461 release_tree_vector (orig_args);
7466 /* Wrapper for above. */
7469 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
7470 tree conversion_path, int flags,
7471 tree *fn_p, tsubst_flags_t complain)
7474 bool subtime = timevar_cond_start (TV_OVERLOAD);
7475 ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags,
7477 timevar_cond_stop (TV_OVERLOAD, subtime);
7481 /* Returns true iff standard conversion sequence ICS1 is a proper
7482 subsequence of ICS2. */
7485 is_subseq (conversion *ics1, conversion *ics2)
7487 /* We can assume that a conversion of the same code
7488 between the same types indicates a subsequence since we only get
7489 here if the types we are converting from are the same. */
7491 while (ics1->kind == ck_rvalue
7492 || ics1->kind == ck_lvalue)
7493 ics1 = ics1->u.next;
7497 while (ics2->kind == ck_rvalue
7498 || ics2->kind == ck_lvalue)
7499 ics2 = ics2->u.next;
7501 if (ics2->kind == ck_user
7502 || ics2->kind == ck_ambig
7503 || ics2->kind == ck_aggr
7504 || ics2->kind == ck_list
7505 || ics2->kind == ck_identity)
7506 /* At this point, ICS1 cannot be a proper subsequence of
7507 ICS2. We can get a USER_CONV when we are comparing the
7508 second standard conversion sequence of two user conversion
7512 ics2 = ics2->u.next;
7514 if (ics2->kind == ics1->kind
7515 && same_type_p (ics2->type, ics1->type)
7516 && same_type_p (ics2->u.next->type,
7517 ics1->u.next->type))
7522 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
7523 be any _TYPE nodes. */
7526 is_properly_derived_from (tree derived, tree base)
7528 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
7531 /* We only allow proper derivation here. The DERIVED_FROM_P macro
7532 considers every class derived from itself. */
7533 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
7534 && DERIVED_FROM_P (base, derived));
7537 /* We build the ICS for an implicit object parameter as a pointer
7538 conversion sequence. However, such a sequence should be compared
7539 as if it were a reference conversion sequence. If ICS is the
7540 implicit conversion sequence for an implicit object parameter,
7541 modify it accordingly. */
7544 maybe_handle_implicit_object (conversion **ics)
7548 /* [over.match.funcs]
7550 For non-static member functions, the type of the
7551 implicit object parameter is "reference to cv X"
7552 where X is the class of which the function is a
7553 member and cv is the cv-qualification on the member
7554 function declaration. */
7555 conversion *t = *ics;
7556 tree reference_type;
7558 /* The `this' parameter is a pointer to a class type. Make the
7559 implicit conversion talk about a reference to that same class
7561 reference_type = TREE_TYPE (t->type);
7562 reference_type = build_reference_type (reference_type);
7564 if (t->kind == ck_qual)
7566 if (t->kind == ck_ptr)
7568 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
7569 t = direct_reference_binding (reference_type, t);
7571 t->rvaluedness_matches_p = 0;
7576 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
7577 and return the initial reference binding conversion. Otherwise,
7578 leave *ICS unchanged and return NULL. */
7581 maybe_handle_ref_bind (conversion **ics)
7583 if ((*ics)->kind == ck_ref_bind)
7585 conversion *old_ics = *ics;
7586 *ics = old_ics->u.next;
7587 (*ics)->user_conv_p = old_ics->user_conv_p;
7594 /* Compare two implicit conversion sequences according to the rules set out in
7595 [over.ics.rank]. Return values:
7597 1: ics1 is better than ics2
7598 -1: ics2 is better than ics1
7599 0: ics1 and ics2 are indistinguishable */
7602 compare_ics (conversion *ics1, conversion *ics2)
7608 tree deref_from_type1 = NULL_TREE;
7609 tree deref_from_type2 = NULL_TREE;
7610 tree deref_to_type1 = NULL_TREE;
7611 tree deref_to_type2 = NULL_TREE;
7612 conversion_rank rank1, rank2;
7614 /* REF_BINDING is nonzero if the result of the conversion sequence
7615 is a reference type. In that case REF_CONV is the reference
7616 binding conversion. */
7617 conversion *ref_conv1;
7618 conversion *ref_conv2;
7620 /* Handle implicit object parameters. */
7621 maybe_handle_implicit_object (&ics1);
7622 maybe_handle_implicit_object (&ics2);
7624 /* Handle reference parameters. */
7625 ref_conv1 = maybe_handle_ref_bind (&ics1);
7626 ref_conv2 = maybe_handle_ref_bind (&ics2);
7628 /* List-initialization sequence L1 is a better conversion sequence than
7629 list-initialization sequence L2 if L1 converts to
7630 std::initializer_list<X> for some X and L2 does not. */
7631 if (ics1->kind == ck_list && ics2->kind != ck_list)
7633 if (ics2->kind == ck_list && ics1->kind != ck_list)
7638 When comparing the basic forms of implicit conversion sequences (as
7639 defined in _over.best.ics_)
7641 --a standard conversion sequence (_over.ics.scs_) is a better
7642 conversion sequence than a user-defined conversion sequence
7643 or an ellipsis conversion sequence, and
7645 --a user-defined conversion sequence (_over.ics.user_) is a
7646 better conversion sequence than an ellipsis conversion sequence
7647 (_over.ics.ellipsis_). */
7648 rank1 = CONVERSION_RANK (ics1);
7649 rank2 = CONVERSION_RANK (ics2);
7653 else if (rank1 < rank2)
7656 if (rank1 == cr_bad)
7658 /* Both ICS are bad. We try to make a decision based on what would
7659 have happened if they'd been good. This is not an extension,
7660 we'll still give an error when we build up the call; this just
7661 helps us give a more helpful error message. */
7662 rank1 = BAD_CONVERSION_RANK (ics1);
7663 rank2 = BAD_CONVERSION_RANK (ics2);
7667 else if (rank1 < rank2)
7670 /* We couldn't make up our minds; try to figure it out below. */
7673 if (ics1->ellipsis_p)
7674 /* Both conversions are ellipsis conversions. */
7677 /* User-defined conversion sequence U1 is a better conversion sequence
7678 than another user-defined conversion sequence U2 if they contain the
7679 same user-defined conversion operator or constructor and if the sec-
7680 ond standard conversion sequence of U1 is better than the second
7681 standard conversion sequence of U2. */
7683 /* Handle list-conversion with the same code even though it isn't always
7684 ranked as a user-defined conversion and it doesn't have a second
7685 standard conversion sequence; it will still have the desired effect.
7686 Specifically, we need to do the reference binding comparison at the
7687 end of this function. */
7689 if (ics1->user_conv_p || ics1->kind == ck_list)
7694 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
7695 if (t1->kind == ck_ambig || t1->kind == ck_aggr
7696 || t1->kind == ck_list)
7698 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
7699 if (t2->kind == ck_ambig || t2->kind == ck_aggr
7700 || t2->kind == ck_list)
7703 if (t1->kind != t2->kind)
7705 else if (t1->kind == ck_user)
7707 if (t1->cand->fn != t2->cand->fn)
7712 /* For ambiguous or aggregate conversions, use the target type as
7713 a proxy for the conversion function. */
7714 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
7718 /* We can just fall through here, after setting up
7719 FROM_TYPE1 and FROM_TYPE2. */
7720 from_type1 = t1->type;
7721 from_type2 = t2->type;
7728 /* We're dealing with two standard conversion sequences.
7732 Standard conversion sequence S1 is a better conversion
7733 sequence than standard conversion sequence S2 if
7735 --S1 is a proper subsequence of S2 (comparing the conversion
7736 sequences in the canonical form defined by _over.ics.scs_,
7737 excluding any Lvalue Transformation; the identity
7738 conversion sequence is considered to be a subsequence of
7739 any non-identity conversion sequence */
7742 while (t1->kind != ck_identity)
7744 from_type1 = t1->type;
7747 while (t2->kind != ck_identity)
7749 from_type2 = t2->type;
7752 /* One sequence can only be a subsequence of the other if they start with
7753 the same type. They can start with different types when comparing the
7754 second standard conversion sequence in two user-defined conversion
7756 if (same_type_p (from_type1, from_type2))
7758 if (is_subseq (ics1, ics2))
7760 if (is_subseq (ics2, ics1))
7768 --the rank of S1 is better than the rank of S2 (by the rules
7771 Standard conversion sequences are ordered by their ranks: an Exact
7772 Match is a better conversion than a Promotion, which is a better
7773 conversion than a Conversion.
7775 Two conversion sequences with the same rank are indistinguishable
7776 unless one of the following rules applies:
7778 --A conversion that does not a convert a pointer, pointer to member,
7779 or std::nullptr_t to bool is better than one that does.
7781 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
7782 so that we do not have to check it explicitly. */
7783 if (ics1->rank < ics2->rank)
7785 else if (ics2->rank < ics1->rank)
7788 to_type1 = ics1->type;
7789 to_type2 = ics2->type;
7791 /* A conversion from scalar arithmetic type to complex is worse than a
7792 conversion between scalar arithmetic types. */
7793 if (same_type_p (from_type1, from_type2)
7794 && ARITHMETIC_TYPE_P (from_type1)
7795 && ARITHMETIC_TYPE_P (to_type1)
7796 && ARITHMETIC_TYPE_P (to_type2)
7797 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
7798 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
7800 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
7806 if (TYPE_PTR_P (from_type1)
7807 && TYPE_PTR_P (from_type2)
7808 && TYPE_PTR_P (to_type1)
7809 && TYPE_PTR_P (to_type2))
7811 deref_from_type1 = TREE_TYPE (from_type1);
7812 deref_from_type2 = TREE_TYPE (from_type2);
7813 deref_to_type1 = TREE_TYPE (to_type1);
7814 deref_to_type2 = TREE_TYPE (to_type2);
7816 /* The rules for pointers to members A::* are just like the rules
7817 for pointers A*, except opposite: if B is derived from A then
7818 A::* converts to B::*, not vice versa. For that reason, we
7819 switch the from_ and to_ variables here. */
7820 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
7821 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
7822 || (TYPE_PTRMEMFUNC_P (from_type1)
7823 && TYPE_PTRMEMFUNC_P (from_type2)
7824 && TYPE_PTRMEMFUNC_P (to_type1)
7825 && TYPE_PTRMEMFUNC_P (to_type2)))
7827 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
7828 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
7829 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
7830 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
7833 if (deref_from_type1 != NULL_TREE
7834 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
7835 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
7837 /* This was one of the pointer or pointer-like conversions.
7841 --If class B is derived directly or indirectly from class A,
7842 conversion of B* to A* is better than conversion of B* to
7843 void*, and conversion of A* to void* is better than
7844 conversion of B* to void*. */
7845 if (TREE_CODE (deref_to_type1) == VOID_TYPE
7846 && TREE_CODE (deref_to_type2) == VOID_TYPE)
7848 if (is_properly_derived_from (deref_from_type1,
7851 else if (is_properly_derived_from (deref_from_type2,
7855 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
7856 || TREE_CODE (deref_to_type2) == VOID_TYPE)
7858 if (same_type_p (deref_from_type1, deref_from_type2))
7860 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
7862 if (is_properly_derived_from (deref_from_type1,
7866 /* We know that DEREF_TO_TYPE1 is `void' here. */
7867 else if (is_properly_derived_from (deref_from_type1,
7872 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
7873 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
7877 --If class B is derived directly or indirectly from class A
7878 and class C is derived directly or indirectly from B,
7880 --conversion of C* to B* is better than conversion of C* to
7883 --conversion of B* to A* is better than conversion of C* to
7885 if (same_type_p (deref_from_type1, deref_from_type2))
7887 if (is_properly_derived_from (deref_to_type1,
7890 else if (is_properly_derived_from (deref_to_type2,
7894 else if (same_type_p (deref_to_type1, deref_to_type2))
7896 if (is_properly_derived_from (deref_from_type2,
7899 else if (is_properly_derived_from (deref_from_type1,
7905 else if (CLASS_TYPE_P (non_reference (from_type1))
7906 && same_type_p (from_type1, from_type2))
7908 tree from = non_reference (from_type1);
7912 --binding of an expression of type C to a reference of type
7913 B& is better than binding an expression of type C to a
7914 reference of type A&
7916 --conversion of C to B is better than conversion of C to A, */
7917 if (is_properly_derived_from (from, to_type1)
7918 && is_properly_derived_from (from, to_type2))
7920 if (is_properly_derived_from (to_type1, to_type2))
7922 else if (is_properly_derived_from (to_type2, to_type1))
7926 else if (CLASS_TYPE_P (non_reference (to_type1))
7927 && same_type_p (to_type1, to_type2))
7929 tree to = non_reference (to_type1);
7933 --binding of an expression of type B to a reference of type
7934 A& is better than binding an expression of type C to a
7935 reference of type A&,
7937 --conversion of B to A is better than conversion of C to A */
7938 if (is_properly_derived_from (from_type1, to)
7939 && is_properly_derived_from (from_type2, to))
7941 if (is_properly_derived_from (from_type2, from_type1))
7943 else if (is_properly_derived_from (from_type1, from_type2))
7950 --S1 and S2 differ only in their qualification conversion and yield
7951 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
7952 qualification signature of type T1 is a proper subset of the cv-
7953 qualification signature of type T2 */
7954 if (ics1->kind == ck_qual
7955 && ics2->kind == ck_qual
7956 && same_type_p (from_type1, from_type2))
7958 int result = comp_cv_qual_signature (to_type1, to_type2);
7965 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
7966 to an implicit object parameter, and either S1 binds an lvalue reference
7967 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
7968 reference to an rvalue and S2 binds an lvalue reference
7969 (C++0x draft standard, 13.3.3.2)
7971 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
7972 types to which the references refer are the same type except for
7973 top-level cv-qualifiers, and the type to which the reference
7974 initialized by S2 refers is more cv-qualified than the type to
7975 which the reference initialized by S1 refers */
7977 if (ref_conv1 && ref_conv2)
7979 if (!ref_conv1->this_p && !ref_conv2->this_p)
7981 if (ref_conv1->rvaluedness_matches_p
7982 > ref_conv2->rvaluedness_matches_p)
7984 if (ref_conv2->rvaluedness_matches_p
7985 > ref_conv1->rvaluedness_matches_p)
7989 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
7990 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
7991 TREE_TYPE (ref_conv1->type));
7994 /* Neither conversion sequence is better than the other. */
7998 /* The source type for this standard conversion sequence. */
8001 source_type (conversion *t)
8003 for (;; t = t->u.next)
8005 if (t->kind == ck_user
8006 || t->kind == ck_ambig
8007 || t->kind == ck_identity)
8013 /* Note a warning about preferring WINNER to LOSER. We do this by storing
8014 a pointer to LOSER and re-running joust to produce the warning if WINNER
8015 is actually used. */
8018 add_warning (struct z_candidate *winner, struct z_candidate *loser)
8020 candidate_warning *cw = (candidate_warning *)
8021 conversion_obstack_alloc (sizeof (candidate_warning));
8023 cw->next = winner->warnings;
8024 winner->warnings = cw;
8027 /* Compare two candidates for overloading as described in
8028 [over.match.best]. Return values:
8030 1: cand1 is better than cand2
8031 -1: cand2 is better than cand1
8032 0: cand1 and cand2 are indistinguishable */
8035 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
8038 int off1 = 0, off2 = 0;
8042 /* Candidates that involve bad conversions are always worse than those
8044 if (cand1->viable > cand2->viable)
8046 if (cand1->viable < cand2->viable)
8049 /* If we have two pseudo-candidates for conversions to the same type,
8050 or two candidates for the same function, arbitrarily pick one. */
8051 if (cand1->fn == cand2->fn
8052 && (IS_TYPE_OR_DECL_P (cand1->fn)))
8055 /* a viable function F1
8056 is defined to be a better function than another viable function F2 if
8057 for all arguments i, ICSi(F1) is not a worse conversion sequence than
8058 ICSi(F2), and then */
8060 /* for some argument j, ICSj(F1) is a better conversion sequence than
8063 /* For comparing static and non-static member functions, we ignore
8064 the implicit object parameter of the non-static function. The
8065 standard says to pretend that the static function has an object
8066 parm, but that won't work with operator overloading. */
8067 len = cand1->num_convs;
8068 if (len != cand2->num_convs)
8070 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
8071 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
8073 gcc_assert (static_1 != static_2);
8084 for (i = 0; i < len; ++i)
8086 conversion *t1 = cand1->convs[i + off1];
8087 conversion *t2 = cand2->convs[i + off2];
8088 int comp = compare_ics (t1, t2);
8093 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
8094 == cr_std + cr_promotion)
8095 && t1->kind == ck_std
8096 && t2->kind == ck_std
8097 && TREE_CODE (t1->type) == INTEGER_TYPE
8098 && TREE_CODE (t2->type) == INTEGER_TYPE
8099 && (TYPE_PRECISION (t1->type)
8100 == TYPE_PRECISION (t2->type))
8101 && (TYPE_UNSIGNED (t1->u.next->type)
8102 || (TREE_CODE (t1->u.next->type)
8105 tree type = t1->u.next->type;
8107 struct z_candidate *w, *l;
8109 type1 = t1->type, type2 = t2->type,
8110 w = cand1, l = cand2;
8112 type1 = t2->type, type2 = t1->type,
8113 w = cand2, l = cand1;
8117 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
8118 type, type1, type2);
8119 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
8125 if (winner && comp != winner)
8134 /* warn about confusing overload resolution for user-defined conversions,
8135 either between a constructor and a conversion op, or between two
8137 if (winner && warn_conversion && cand1->second_conv
8138 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
8139 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
8141 struct z_candidate *w, *l;
8142 bool give_warning = false;
8145 w = cand1, l = cand2;
8147 w = cand2, l = cand1;
8149 /* We don't want to complain about `X::operator T1 ()'
8150 beating `X::operator T2 () const', when T2 is a no less
8151 cv-qualified version of T1. */
8152 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
8153 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
8155 tree t = TREE_TYPE (TREE_TYPE (l->fn));
8156 tree f = TREE_TYPE (TREE_TYPE (w->fn));
8158 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
8163 if (!comp_ptr_ttypes (t, f))
8164 give_warning = true;
8167 give_warning = true;
8173 tree source = source_type (w->convs[0]);
8174 if (! DECL_CONSTRUCTOR_P (w->fn))
8175 source = TREE_TYPE (source);
8176 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
8177 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
8178 source, w->second_conv->type))
8180 inform (input_location, " because conversion sequence for the argument is better");
8191 F1 is a non-template function and F2 is a template function
8194 if (!cand1->template_decl && cand2->template_decl)
8196 else if (cand1->template_decl && !cand2->template_decl)
8200 F1 and F2 are template functions and the function template for F1 is
8201 more specialized than the template for F2 according to the partial
8204 if (cand1->template_decl && cand2->template_decl)
8206 winner = more_specialized_fn
8207 (TI_TEMPLATE (cand1->template_decl),
8208 TI_TEMPLATE (cand2->template_decl),
8209 /* [temp.func.order]: The presence of unused ellipsis and default
8210 arguments has no effect on the partial ordering of function
8211 templates. add_function_candidate() will not have
8212 counted the "this" argument for constructors. */
8213 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
8219 the context is an initialization by user-defined conversion (see
8220 _dcl.init_ and _over.match.user_) and the standard conversion
8221 sequence from the return type of F1 to the destination type (i.e.,
8222 the type of the entity being initialized) is a better conversion
8223 sequence than the standard conversion sequence from the return type
8224 of F2 to the destination type. */
8226 if (cand1->second_conv)
8228 winner = compare_ics (cand1->second_conv, cand2->second_conv);
8233 /* Check whether we can discard a builtin candidate, either because we
8234 have two identical ones or matching builtin and non-builtin candidates.
8236 (Pedantically in the latter case the builtin which matched the user
8237 function should not be added to the overload set, but we spot it here.
8240 ... the builtin candidates include ...
8241 - do not have the same parameter type list as any non-template
8242 non-member candidate. */
8244 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
8245 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
8247 for (i = 0; i < len; ++i)
8248 if (!same_type_p (cand1->convs[i]->type,
8249 cand2->convs[i]->type))
8251 if (i == cand1->num_convs)
8253 if (cand1->fn == cand2->fn)
8254 /* Two built-in candidates; arbitrarily pick one. */
8256 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
8257 /* cand1 is built-in; prefer cand2. */
8260 /* cand2 is built-in; prefer cand1. */
8265 /* If the two function declarations represent the same function (this can
8266 happen with declarations in multiple scopes and arg-dependent lookup),
8267 arbitrarily choose one. But first make sure the default args we're
8269 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
8270 && equal_functions (cand1->fn, cand2->fn))
8272 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
8273 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
8275 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
8277 for (i = 0; i < len; ++i)
8279 /* Don't crash if the fn is variadic. */
8282 parms1 = TREE_CHAIN (parms1);
8283 parms2 = TREE_CHAIN (parms2);
8287 parms1 = TREE_CHAIN (parms1);
8289 parms2 = TREE_CHAIN (parms2);
8293 if (!cp_tree_equal (TREE_PURPOSE (parms1),
8294 TREE_PURPOSE (parms2)))
8298 permerror (input_location, "default argument mismatch in "
8299 "overload resolution");
8300 inform (input_location,
8301 " candidate 1: %q+#F", cand1->fn);
8302 inform (input_location,
8303 " candidate 2: %q+#F", cand2->fn);
8306 add_warning (cand1, cand2);
8309 parms1 = TREE_CHAIN (parms1);
8310 parms2 = TREE_CHAIN (parms2);
8318 /* Extension: If the worst conversion for one candidate is worse than the
8319 worst conversion for the other, take the first. */
8322 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
8323 struct z_candidate *w = 0, *l = 0;
8325 for (i = 0; i < len; ++i)
8327 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
8328 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
8329 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
8330 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
8333 winner = 1, w = cand1, l = cand2;
8335 winner = -1, w = cand2, l = cand1;
8338 /* Don't choose a deleted function over ambiguity. */
8339 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
8343 pedwarn (input_location, 0,
8344 "ISO C++ says that these are ambiguous, even "
8345 "though the worst conversion for the first is better than "
8346 "the worst conversion for the second:");
8347 print_z_candidate (_("candidate 1:"), w);
8348 print_z_candidate (_("candidate 2:"), l);
8356 gcc_assert (!winner);
8360 /* Given a list of candidates for overloading, find the best one, if any.
8361 This algorithm has a worst case of O(2n) (winner is last), and a best
8362 case of O(n/2) (totally ambiguous); much better than a sorting
8365 static struct z_candidate *
8366 tourney (struct z_candidate *candidates)
8368 struct z_candidate *champ = candidates, *challenger;
8370 int champ_compared_to_predecessor = 0;
8372 /* Walk through the list once, comparing each current champ to the next
8373 candidate, knocking out a candidate or two with each comparison. */
8375 for (challenger = champ->next; challenger; )
8377 fate = joust (champ, challenger, 0);
8379 challenger = challenger->next;
8384 champ = challenger->next;
8387 champ_compared_to_predecessor = 0;
8392 champ_compared_to_predecessor = 1;
8395 challenger = champ->next;
8399 /* Make sure the champ is better than all the candidates it hasn't yet
8400 been compared to. */
8402 for (challenger = candidates;
8404 && !(champ_compared_to_predecessor && challenger->next == champ);
8405 challenger = challenger->next)
8407 fate = joust (champ, challenger, 0);
8415 /* Returns nonzero if things of type FROM can be converted to TO. */
8418 can_convert (tree to, tree from)
8420 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
8423 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
8426 can_convert_arg (tree to, tree from, tree arg, int flags)
8432 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8433 p = conversion_obstack_alloc (0);
8435 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8437 ok_p = (t && !t->bad_p);
8439 /* Free all the conversions we allocated. */
8440 obstack_free (&conversion_obstack, p);
8445 /* Like can_convert_arg, but allows dubious conversions as well. */
8448 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
8453 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8454 p = conversion_obstack_alloc (0);
8455 /* Try to perform the conversion. */
8456 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8458 /* Free all the conversions we allocated. */
8459 obstack_free (&conversion_obstack, p);
8464 /* Convert EXPR to TYPE. Return the converted expression.
8466 Note that we allow bad conversions here because by the time we get to
8467 this point we are committed to doing the conversion. If we end up
8468 doing a bad conversion, convert_like will complain. */
8471 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
8476 if (error_operand_p (expr))
8477 return error_mark_node;
8479 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8480 p = conversion_obstack_alloc (0);
8482 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8488 if (complain & tf_error)
8490 /* If expr has unknown type, then it is an overloaded function.
8491 Call instantiate_type to get good error messages. */
8492 if (TREE_TYPE (expr) == unknown_type_node)
8493 instantiate_type (type, expr, complain);
8494 else if (invalid_nonstatic_memfn_p (expr, complain))
8495 /* We gave an error. */;
8497 error ("could not convert %qE from %qT to %qT", expr,
8498 TREE_TYPE (expr), type);
8500 expr = error_mark_node;
8502 else if (processing_template_decl)
8504 /* In a template, we are only concerned about determining the
8505 type of non-dependent expressions, so we do not have to
8506 perform the actual conversion. */
8507 if (TREE_TYPE (expr) != type)
8508 expr = build_nop (type, expr);
8511 expr = convert_like (conv, expr, complain);
8513 /* Free all the conversions we allocated. */
8514 obstack_free (&conversion_obstack, p);
8520 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
8522 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
8525 /* Convert EXPR to TYPE (as a direct-initialization) if that is
8526 permitted. If the conversion is valid, the converted expression is
8527 returned. Otherwise, NULL_TREE is returned, except in the case
8528 that TYPE is a class type; in that case, an error is issued. If
8529 C_CAST_P is true, then this direct-initialization is taking
8530 place as part of a static_cast being attempted as part of a C-style
8534 perform_direct_initialization_if_possible (tree type,
8537 tsubst_flags_t complain)
8542 if (type == error_mark_node || error_operand_p (expr))
8543 return error_mark_node;
8546 If the destination type is a (possibly cv-qualified) class type:
8548 -- If the initialization is direct-initialization ...,
8549 constructors are considered. ... If no constructor applies, or
8550 the overload resolution is ambiguous, the initialization is
8552 if (CLASS_TYPE_P (type))
8554 VEC(tree,gc) *args = make_tree_vector_single (expr);
8555 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
8556 &args, type, LOOKUP_NORMAL, complain);
8557 release_tree_vector (args);
8558 return build_cplus_new (type, expr, complain);
8561 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8562 p = conversion_obstack_alloc (0);
8564 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8567 if (!conv || conv->bad_p)
8570 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
8571 /*issue_conversion_warnings=*/false,
8575 /* Free all the conversions we allocated. */
8576 obstack_free (&conversion_obstack, p);
8581 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
8582 is being bound to a temporary. Create and return a new VAR_DECL
8583 with the indicated TYPE; this variable will store the value to
8584 which the reference is bound. */
8587 make_temporary_var_for_ref_to_temp (tree decl, tree type)
8591 /* Create the variable. */
8592 var = create_temporary_var (type);
8594 /* Register the variable. */
8595 if (TREE_STATIC (decl))
8597 /* Namespace-scope or local static; give it a mangled name. */
8600 TREE_STATIC (var) = 1;
8601 name = mangle_ref_init_variable (decl);
8602 DECL_NAME (var) = name;
8603 SET_DECL_ASSEMBLER_NAME (var, name);
8604 var = pushdecl_top_level (var);
8607 /* Create a new cleanup level if necessary. */
8608 maybe_push_cleanup_level (type);
8613 /* EXPR is the initializer for a variable DECL of reference or
8614 std::initializer_list type. Create, push and return a new VAR_DECL
8615 for the initializer so that it will live as long as DECL. Any
8616 cleanup for the new variable is returned through CLEANUP, and the
8617 code to initialize the new variable is returned through INITP. */
8620 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
8626 /* Create the temporary variable. */
8627 type = TREE_TYPE (expr);
8628 var = make_temporary_var_for_ref_to_temp (decl, type);
8629 layout_decl (var, 0);
8630 /* If the rvalue is the result of a function call it will be
8631 a TARGET_EXPR. If it is some other construct (such as a
8632 member access expression where the underlying object is
8633 itself the result of a function call), turn it into a
8634 TARGET_EXPR here. It is important that EXPR be a
8635 TARGET_EXPR below since otherwise the INIT_EXPR will
8636 attempt to make a bitwise copy of EXPR to initialize
8638 if (TREE_CODE (expr) != TARGET_EXPR)
8639 expr = get_target_expr (expr);
8641 /* If the initializer is constant, put it in DECL_INITIAL so we get
8642 static initialization and use in constant expressions. */
8643 init = maybe_constant_init (expr);
8644 if (TREE_CONSTANT (init))
8646 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
8648 /* 5.19 says that a constant expression can include an
8649 lvalue-rvalue conversion applied to "a glvalue of literal type
8650 that refers to a non-volatile temporary object initialized
8651 with a constant expression". Rather than try to communicate
8652 that this VAR_DECL is a temporary, just mark it constexpr.
8654 Currently this is only useful for initializer_list temporaries,
8655 since reference vars can't appear in constant expressions. */
8656 DECL_DECLARED_CONSTEXPR_P (var) = true;
8657 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
8658 TREE_CONSTANT (var) = true;
8660 DECL_INITIAL (var) = init;
8664 /* Create the INIT_EXPR that will initialize the temporary
8666 init = build2 (INIT_EXPR, type, var, expr);
8667 if (at_function_scope_p ())
8669 add_decl_expr (var);
8671 if (TREE_STATIC (var))
8672 init = add_stmt_to_compound (init, register_dtor_fn (var));
8674 *cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error);
8676 /* We must be careful to destroy the temporary only
8677 after its initialization has taken place. If the
8678 initialization throws an exception, then the
8679 destructor should not be run. We cannot simply
8680 transform INIT into something like:
8682 (INIT, ({ CLEANUP_STMT; }))
8684 because emit_local_var always treats the
8685 initializer as a full-expression. Thus, the
8686 destructor would run too early; it would run at the
8687 end of initializing the reference variable, rather
8688 than at the end of the block enclosing the
8691 The solution is to pass back a cleanup expression
8692 which the caller is responsible for attaching to
8693 the statement tree. */
8697 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
8698 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
8699 static_aggregates = tree_cons (NULL_TREE, var,
8707 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
8708 initializing a variable of that TYPE. If DECL is non-NULL, it is
8709 the VAR_DECL being initialized with the EXPR. (In that case, the
8710 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
8711 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
8712 return, if *CLEANUP is no longer NULL, it will be an expression
8713 that should be pushed as a cleanup after the returned expression
8714 is used to initialize DECL.
8716 Return the converted expression. */
8719 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
8720 tsubst_flags_t complain)
8725 if (type == error_mark_node || error_operand_p (expr))
8726 return error_mark_node;
8728 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8729 p = conversion_obstack_alloc (0);
8731 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
8733 if (!conv || conv->bad_p)
8735 if (complain & tf_error)
8737 if (!CP_TYPE_CONST_P (TREE_TYPE (type))
8738 && !TYPE_REF_IS_RVALUE (type)
8739 && !real_lvalue_p (expr))
8740 error ("invalid initialization of non-const reference of "
8741 "type %qT from an rvalue of type %qT",
8742 type, TREE_TYPE (expr));
8744 error ("invalid initialization of reference of type "
8745 "%qT from expression of type %qT", type,
8748 return error_mark_node;
8751 /* If DECL is non-NULL, then this special rule applies:
8755 The temporary to which the reference is bound or the temporary
8756 that is the complete object to which the reference is bound
8757 persists for the lifetime of the reference.
8759 The temporaries created during the evaluation of the expression
8760 initializing the reference, except the temporary to which the
8761 reference is bound, are destroyed at the end of the
8762 full-expression in which they are created.
8764 In that case, we store the converted expression into a new
8765 VAR_DECL in a new scope.
8767 However, we want to be careful not to create temporaries when
8768 they are not required. For example, given:
8771 struct D : public B {};
8775 there is no need to copy the return value from "f"; we can just
8776 extend its lifetime. Similarly, given:
8779 struct T { operator S(); };
8783 we can extend the lifetime of the return value of the conversion
8785 gcc_assert (conv->kind == ck_ref_bind);
8789 tree base_conv_type;
8791 gcc_assert (complain == tf_warning_or_error);
8793 /* Skip over the REF_BIND. */
8794 conv = conv->u.next;
8795 /* If the next conversion is a BASE_CONV, skip that too -- but
8796 remember that the conversion was required. */
8797 if (conv->kind == ck_base)
8799 base_conv_type = conv->type;
8800 conv = conv->u.next;
8803 base_conv_type = NULL_TREE;
8804 /* Perform the remainder of the conversion. */
8805 expr = convert_like_real (conv, expr,
8806 /*fn=*/NULL_TREE, /*argnum=*/0,
8808 /*issue_conversion_warnings=*/true,
8811 if (error_operand_p (expr))
8812 expr = error_mark_node;
8815 if (!lvalue_or_rvalue_with_address_p (expr))
8818 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
8819 /* Use its address to initialize the reference variable. */
8820 expr = build_address (var);
8822 expr = convert_to_base (expr,
8823 build_pointer_type (base_conv_type),
8824 /*check_access=*/true,
8825 /*nonnull=*/true, complain);
8827 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
8830 /* Take the address of EXPR. */
8831 expr = cp_build_addr_expr (expr, complain);
8832 /* If a BASE_CONV was required, perform it now. */
8834 expr = (perform_implicit_conversion
8835 (build_pointer_type (base_conv_type), expr,
8837 expr = build_nop (type, expr);
8841 /* Perform the conversion. */
8842 expr = convert_like (conv, expr, complain);
8844 /* Free all the conversions we allocated. */
8845 obstack_free (&conversion_obstack, p);
8850 /* Returns true iff TYPE is some variant of std::initializer_list. */
8853 is_std_init_list (tree type)
8855 /* Look through typedefs. */
8858 type = TYPE_MAIN_VARIANT (type);
8859 return (CLASS_TYPE_P (type)
8860 && CP_TYPE_CONTEXT (type) == std_node
8861 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
8864 /* Returns true iff DECL is a list constructor: i.e. a constructor which
8865 will accept an argument list of a single std::initializer_list<T>. */
8868 is_list_ctor (tree decl)
8870 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
8873 if (!args || args == void_list_node)
8876 arg = non_reference (TREE_VALUE (args));
8877 if (!is_std_init_list (arg))
8880 args = TREE_CHAIN (args);
8882 if (args && args != void_list_node && !TREE_PURPOSE (args))
8883 /* There are more non-defaulted parms. */
8889 #include "gt-cp-call.h"