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, ck_ambig nor
115 ck_list. Please use the next_conversion function instead
116 of using this field directly. */
118 /* The expression at the beginning of the conversion chain. This
119 variant is used only if KIND is ck_identity or ck_ambig. */
121 /* The array of conversions for an initializer_list, so this
122 variant is used only when KIN D is ck_list. */
125 /* The function candidate corresponding to this conversion
126 sequence. This field is only used if KIND is ck_user. */
127 struct z_candidate *cand;
130 #define CONVERSION_RANK(NODE) \
131 ((NODE)->bad_p ? cr_bad \
132 : (NODE)->ellipsis_p ? cr_ellipsis \
133 : (NODE)->user_conv_p ? cr_user \
136 #define BAD_CONVERSION_RANK(NODE) \
137 ((NODE)->ellipsis_p ? cr_ellipsis \
138 : (NODE)->user_conv_p ? cr_user \
141 static struct obstack conversion_obstack;
142 static bool conversion_obstack_initialized;
143 struct rejection_reason;
145 static struct z_candidate * tourney (struct z_candidate *);
146 static int equal_functions (tree, tree);
147 static int joust (struct z_candidate *, struct z_candidate *, bool);
148 static int compare_ics (conversion *, conversion *);
149 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
150 static tree build_java_interface_fn_ref (tree, tree);
151 #define convert_like(CONV, EXPR, COMPLAIN) \
152 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
153 /*issue_conversion_warnings=*/true, \
154 /*c_cast_p=*/false, (COMPLAIN))
155 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
156 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
157 /*issue_conversion_warnings=*/true, \
158 /*c_cast_p=*/false, (COMPLAIN))
159 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
160 bool, tsubst_flags_t);
161 static void op_error (enum tree_code, enum tree_code, tree, tree,
163 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
164 static void print_z_candidate (const char *, struct z_candidate *);
165 static void print_z_candidates (location_t, struct z_candidate *);
166 static tree build_this (tree);
167 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
168 static bool any_strictly_viable (struct z_candidate *);
169 static struct z_candidate *add_template_candidate
170 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
171 tree, tree, tree, int, unification_kind_t);
172 static struct z_candidate *add_template_candidate_real
173 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
174 tree, tree, tree, int, tree, unification_kind_t);
175 static struct z_candidate *add_template_conv_candidate
176 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
178 static void add_builtin_candidates
179 (struct z_candidate **, enum tree_code, enum tree_code,
181 static void add_builtin_candidate
182 (struct z_candidate **, enum tree_code, enum tree_code,
183 tree, tree, tree, tree *, tree *, int);
184 static bool is_complete (tree);
185 static void build_builtin_candidate
186 (struct z_candidate **, tree, tree, tree, tree *, tree *,
188 static struct z_candidate *add_conv_candidate
189 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
191 static struct z_candidate *add_function_candidate
192 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
194 static conversion *implicit_conversion (tree, tree, tree, bool, int);
195 static conversion *standard_conversion (tree, tree, tree, bool, int);
196 static conversion *reference_binding (tree, tree, tree, bool, int);
197 static conversion *build_conv (conversion_kind, tree, conversion *);
198 static conversion *build_list_conv (tree, tree, int);
199 static conversion *next_conversion (conversion *);
200 static bool is_subseq (conversion *, conversion *);
201 static conversion *maybe_handle_ref_bind (conversion **);
202 static void maybe_handle_implicit_object (conversion **);
203 static struct z_candidate *add_candidate
204 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
205 conversion **, tree, tree, int, struct rejection_reason *);
206 static tree source_type (conversion *);
207 static void add_warning (struct z_candidate *, struct z_candidate *);
208 static bool reference_compatible_p (tree, tree);
209 static conversion *direct_reference_binding (tree, conversion *);
210 static bool promoted_arithmetic_type_p (tree);
211 static conversion *conditional_conversion (tree, tree);
212 static char *name_as_c_string (tree, tree, bool *);
213 static tree prep_operand (tree);
214 static void add_candidates (tree, tree, const VEC(tree,gc) *, tree, tree, bool,
215 tree, tree, int, struct z_candidate **);
216 static conversion *merge_conversion_sequences (conversion *, conversion *);
217 static bool magic_varargs_p (tree);
218 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
220 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
221 NAME can take many forms... */
224 check_dtor_name (tree basetype, tree name)
226 /* Just accept something we've already complained about. */
227 if (name == error_mark_node)
230 if (TREE_CODE (name) == TYPE_DECL)
231 name = TREE_TYPE (name);
232 else if (TYPE_P (name))
234 else if (TREE_CODE (name) == IDENTIFIER_NODE)
236 if ((MAYBE_CLASS_TYPE_P (basetype)
237 && name == constructor_name (basetype))
238 || (TREE_CODE (basetype) == ENUMERAL_TYPE
239 && name == TYPE_IDENTIFIER (basetype)))
242 name = get_type_value (name);
248 template <class T> struct S { ~S(); };
252 NAME will be a class template. */
253 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
257 if (!name || name == error_mark_node)
259 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
262 /* We want the address of a function or method. We avoid creating a
263 pointer-to-member function. */
266 build_addr_func (tree function)
268 tree type = TREE_TYPE (function);
270 /* We have to do these by hand to avoid real pointer to member
272 if (TREE_CODE (type) == METHOD_TYPE)
274 if (TREE_CODE (function) == OFFSET_REF)
276 tree object = build_address (TREE_OPERAND (function, 0));
277 return get_member_function_from_ptrfunc (&object,
278 TREE_OPERAND (function, 1));
280 function = build_address (function);
283 function = decay_conversion (function);
288 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
289 POINTER_TYPE to those. Note, pointer to member function types
290 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
291 two variants. build_call_a is the primitive taking an array of
292 arguments, while build_call_n is a wrapper that handles varargs. */
295 build_call_n (tree function, int n, ...)
298 return build_call_a (function, 0, NULL);
301 tree *argarray = XALLOCAVEC (tree, n);
306 for (i = 0; i < n; i++)
307 argarray[i] = va_arg (ap, tree);
309 return build_call_a (function, n, argarray);
313 /* Update various flags in cfun and the call itself based on what is being
314 called. Split out of build_call_a so that bot_manip can use it too. */
317 set_flags_from_callee (tree call)
320 tree decl = get_callee_fndecl (call);
322 /* We check both the decl and the type; a function may be known not to
323 throw without being declared throw(). */
324 nothrow = ((decl && TREE_NOTHROW (decl))
325 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call)))));
327 if (!nothrow && at_function_scope_p () && cfun && cp_function_chain)
328 cp_function_chain->can_throw = 1;
330 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
331 current_function_returns_abnormally = 1;
333 TREE_NOTHROW (call) = nothrow;
337 build_call_a (tree function, int n, tree *argarray)
344 function = build_addr_func (function);
346 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
347 fntype = TREE_TYPE (TREE_TYPE (function));
348 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
349 || TREE_CODE (fntype) == METHOD_TYPE);
350 result_type = TREE_TYPE (fntype);
351 /* An rvalue has no cv-qualifiers. */
352 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
353 result_type = cv_unqualified (result_type);
355 function = build_call_array_loc (input_location,
356 result_type, function, n, argarray);
357 set_flags_from_callee (function);
359 decl = get_callee_fndecl (function);
361 if (decl && !TREE_USED (decl))
363 /* We invoke build_call directly for several library
364 functions. These may have been declared normally if
365 we're building libgcc, so we can't just check
367 gcc_assert (DECL_ARTIFICIAL (decl)
368 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
373 if (decl && TREE_DEPRECATED (decl))
374 warn_deprecated_use (decl, NULL_TREE);
375 require_complete_eh_spec_types (fntype, decl);
377 TREE_HAS_CONSTRUCTOR (function) = (decl && DECL_CONSTRUCTOR_P (decl));
379 /* Don't pass empty class objects by value. This is useful
380 for tags in STL, which are used to control overload resolution.
381 We don't need to handle other cases of copying empty classes. */
382 if (! decl || ! DECL_BUILT_IN (decl))
383 for (i = 0; i < n; i++)
385 tree arg = CALL_EXPR_ARG (function, i);
386 if (is_empty_class (TREE_TYPE (arg))
387 && ! TREE_ADDRESSABLE (TREE_TYPE (arg)))
389 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (arg));
390 arg = build2 (COMPOUND_EXPR, TREE_TYPE (t), arg, t);
391 CALL_EXPR_ARG (function, i) = arg;
398 /* Build something of the form ptr->method (args)
399 or object.method (args). This can also build
400 calls to constructors, and find friends.
402 Member functions always take their class variable
405 INSTANCE is a class instance.
407 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
409 PARMS help to figure out what that NAME really refers to.
411 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
412 down to the real instance type to use for access checking. We need this
413 information to get protected accesses correct.
415 FLAGS is the logical disjunction of zero or more LOOKUP_
416 flags. See cp-tree.h for more info.
418 If this is all OK, calls build_function_call with the resolved
421 This function must also handle being called to perform
422 initialization, promotion/coercion of arguments, and
423 instantiation of default parameters.
425 Note that NAME may refer to an instance variable name. If
426 `operator()()' is defined for the type of that field, then we return
429 /* New overloading code. */
431 typedef struct z_candidate z_candidate;
433 typedef struct candidate_warning candidate_warning;
434 struct candidate_warning {
436 candidate_warning *next;
439 /* Information for providing diagnostics about why overloading failed. */
441 enum rejection_reason_code {
444 rr_explicit_conversion,
445 rr_template_conversion,
447 rr_bad_arg_conversion,
448 rr_template_unification,
449 rr_template_instantiation,
453 struct conversion_info {
454 /* The index of the argument, 0-based. */
456 /* The type of the actual argument. */
458 /* The type of the formal argument. */
462 struct rejection_reason {
463 enum rejection_reason_code code;
465 /* Information about an arity mismatch. */
467 /* The expected number of arguments. */
469 /* The actual number of arguments in the call. */
471 /* Whether the call was a varargs call. */
474 /* Information about an argument conversion mismatch. */
475 struct conversion_info conversion;
476 /* Same, but for bad argument conversions. */
477 struct conversion_info bad_conversion;
478 /* Information about template unification failures. These are the
479 parameters passed to fn_type_unification. */
487 unification_kind_t strict;
489 } template_unification;
490 /* Information about template instantiation failures. These are the
491 parameters passed to instantiate_template. */
495 } template_instantiation;
500 /* The FUNCTION_DECL that will be called if this candidate is
501 selected by overload resolution. */
503 /* If not NULL_TREE, the first argument to use when calling this
506 /* The rest of the arguments to use when calling this function. If
507 there are no further arguments this may be NULL or it may be an
509 const VEC(tree,gc) *args;
510 /* The implicit conversion sequences for each of the arguments to
513 /* The number of implicit conversion sequences. */
515 /* If FN is a user-defined conversion, the standard conversion
516 sequence from the type returned by FN to the desired destination
518 conversion *second_conv;
520 struct rejection_reason *reason;
521 /* If FN is a member function, the binfo indicating the path used to
522 qualify the name of FN at the call site. This path is used to
523 determine whether or not FN is accessible if it is selected by
524 overload resolution. The DECL_CONTEXT of FN will always be a
525 (possibly improper) base of this binfo. */
527 /* If FN is a non-static member function, the binfo indicating the
528 subobject to which the `this' pointer should be converted if FN
529 is selected by overload resolution. The type pointed to by
530 the `this' pointer must correspond to the most derived class
531 indicated by the CONVERSION_PATH. */
532 tree conversion_path;
535 candidate_warning *warnings;
539 /* Returns true iff T is a null pointer constant in the sense of
543 null_ptr_cst_p (tree t)
547 A null pointer constant is an integral constant expression
548 (_expr.const_) rvalue of integer type that evaluates to zero or
549 an rvalue of type std::nullptr_t. */
550 if (NULLPTR_TYPE_P (TREE_TYPE (t)))
552 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
554 /* Core issue 903 says only literal 0 is a null pointer constant. */
555 if (cxx_dialect < cxx0x)
556 t = integral_constant_value (t);
558 if (integer_zerop (t) && !TREE_OVERFLOW (t))
564 /* Returns true iff T is a null member pointer value (4.11). */
567 null_member_pointer_value_p (tree t)
569 tree type = TREE_TYPE (t);
572 else if (TYPE_PTRMEMFUNC_P (type))
573 return (TREE_CODE (t) == CONSTRUCTOR
574 && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value));
575 else if (TYPE_PTRMEM_P (type))
576 return integer_all_onesp (t);
581 /* Returns nonzero if PARMLIST consists of only default parms,
582 ellipsis, and/or undeduced parameter packs. */
585 sufficient_parms_p (const_tree parmlist)
587 for (; parmlist && parmlist != void_list_node;
588 parmlist = TREE_CHAIN (parmlist))
589 if (!TREE_PURPOSE (parmlist)
590 && !PACK_EXPANSION_P (TREE_VALUE (parmlist)))
595 /* Allocate N bytes of memory from the conversion obstack. The memory
596 is zeroed before being returned. */
599 conversion_obstack_alloc (size_t n)
602 if (!conversion_obstack_initialized)
604 gcc_obstack_init (&conversion_obstack);
605 conversion_obstack_initialized = true;
607 p = obstack_alloc (&conversion_obstack, n);
612 /* Allocate rejection reasons. */
614 static struct rejection_reason *
615 alloc_rejection (enum rejection_reason_code code)
617 struct rejection_reason *p;
618 p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p);
623 static struct rejection_reason *
624 arity_rejection (tree first_arg, int expected, int actual)
626 struct rejection_reason *r = alloc_rejection (rr_arity);
627 int adjust = first_arg != NULL_TREE;
628 r->u.arity.expected = expected - adjust;
629 r->u.arity.actual = actual - adjust;
633 static struct rejection_reason *
634 arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
636 struct rejection_reason *r = alloc_rejection (rr_arg_conversion);
637 int adjust = first_arg != NULL_TREE;
638 r->u.conversion.n_arg = n_arg - adjust;
639 r->u.conversion.from_type = from;
640 r->u.conversion.to_type = to;
644 static struct rejection_reason *
645 bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
647 struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion);
648 int adjust = first_arg != NULL_TREE;
649 r->u.bad_conversion.n_arg = n_arg - adjust;
650 r->u.bad_conversion.from_type = from;
651 r->u.bad_conversion.to_type = to;
655 static struct rejection_reason *
656 explicit_conversion_rejection (tree from, tree to)
658 struct rejection_reason *r = alloc_rejection (rr_explicit_conversion);
659 r->u.conversion.n_arg = 0;
660 r->u.conversion.from_type = from;
661 r->u.conversion.to_type = to;
665 static struct rejection_reason *
666 template_conversion_rejection (tree from, tree to)
668 struct rejection_reason *r = alloc_rejection (rr_template_conversion);
669 r->u.conversion.n_arg = 0;
670 r->u.conversion.from_type = from;
671 r->u.conversion.to_type = to;
675 static struct rejection_reason *
676 template_unification_rejection (tree tmpl, tree explicit_targs, tree targs,
677 const tree *args, unsigned int nargs,
678 tree return_type, unification_kind_t strict,
681 size_t args_n_bytes = sizeof (*args) * nargs;
682 tree *args1 = (tree *) conversion_obstack_alloc (args_n_bytes);
683 struct rejection_reason *r = alloc_rejection (rr_template_unification);
684 r->u.template_unification.tmpl = tmpl;
685 r->u.template_unification.explicit_targs = explicit_targs;
686 r->u.template_unification.targs = targs;
687 /* Copy args to our own storage. */
688 memcpy (args1, args, args_n_bytes);
689 r->u.template_unification.args = args1;
690 r->u.template_unification.nargs = nargs;
691 r->u.template_unification.return_type = return_type;
692 r->u.template_unification.strict = strict;
693 r->u.template_unification.flags = flags;
697 static struct rejection_reason *
698 template_unification_error_rejection (void)
700 return alloc_rejection (rr_template_unification);
703 static struct rejection_reason *
704 template_instantiation_rejection (tree tmpl, tree targs)
706 struct rejection_reason *r = alloc_rejection (rr_template_instantiation);
707 r->u.template_instantiation.tmpl = tmpl;
708 r->u.template_instantiation.targs = targs;
712 static struct rejection_reason *
713 invalid_copy_with_fn_template_rejection (void)
715 struct rejection_reason *r = alloc_rejection (rr_invalid_copy);
719 /* Dynamically allocate a conversion. */
722 alloc_conversion (conversion_kind kind)
725 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
730 #ifdef ENABLE_CHECKING
732 /* Make sure that all memory on the conversion obstack has been
736 validate_conversion_obstack (void)
738 if (conversion_obstack_initialized)
739 gcc_assert ((obstack_next_free (&conversion_obstack)
740 == obstack_base (&conversion_obstack)));
743 #endif /* ENABLE_CHECKING */
745 /* Dynamically allocate an array of N conversions. */
748 alloc_conversions (size_t n)
750 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
754 build_conv (conversion_kind code, tree type, conversion *from)
757 conversion_rank rank = CONVERSION_RANK (from);
759 /* Note that the caller is responsible for filling in t->cand for
760 user-defined conversions. */
761 t = alloc_conversion (code);
784 t->user_conv_p = (code == ck_user || from->user_conv_p);
785 t->bad_p = from->bad_p;
790 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
791 specialization of std::initializer_list<T>, if such a conversion is
795 build_list_conv (tree type, tree ctor, int flags)
797 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
798 unsigned len = CONSTRUCTOR_NELTS (ctor);
799 conversion **subconvs = alloc_conversions (len);
804 /* Within a list-initialization we can have more user-defined
806 flags &= ~LOOKUP_NO_CONVERSION;
807 /* But no narrowing conversions. */
808 flags |= LOOKUP_NO_NARROWING;
810 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
813 = implicit_conversion (elttype, TREE_TYPE (val), val,
821 t = alloc_conversion (ck_list);
823 t->u.list = subconvs;
826 for (i = 0; i < len; ++i)
828 conversion *sub = subconvs[i];
829 if (sub->rank > t->rank)
831 if (sub->user_conv_p)
832 t->user_conv_p = true;
840 /* Return the next conversion of the conversion chain (if applicable),
841 or NULL otherwise. Please use this function instead of directly
842 accessing fields of struct conversion. */
845 next_conversion (conversion *conv)
848 || conv->kind == ck_identity
849 || conv->kind == ck_ambig
850 || conv->kind == ck_list)
855 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
856 is a valid aggregate initializer for array type ATYPE. */
859 can_convert_array (tree atype, tree ctor, int flags)
862 tree elttype = TREE_TYPE (atype);
863 for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
865 tree val = CONSTRUCTOR_ELT (ctor, i)->value;
867 if (TREE_CODE (elttype) == ARRAY_TYPE
868 && TREE_CODE (val) == CONSTRUCTOR)
869 ok = can_convert_array (elttype, val, flags);
871 ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags);
878 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
879 aggregate class, if such a conversion is possible. */
882 build_aggr_conv (tree type, tree ctor, int flags)
884 unsigned HOST_WIDE_INT i = 0;
886 tree field = next_initializable_field (TYPE_FIELDS (type));
887 tree empty_ctor = NULL_TREE;
889 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
891 tree ftype = TREE_TYPE (field);
895 if (i < CONSTRUCTOR_NELTS (ctor))
896 val = CONSTRUCTOR_ELT (ctor, i)->value;
899 if (empty_ctor == NULL_TREE)
900 empty_ctor = build_constructor (init_list_type_node, NULL);
905 if (TREE_CODE (ftype) == ARRAY_TYPE
906 && TREE_CODE (val) == CONSTRUCTOR)
907 ok = can_convert_array (ftype, val, flags);
909 ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags);
914 if (TREE_CODE (type) == UNION_TYPE)
918 if (i < CONSTRUCTOR_NELTS (ctor))
921 c = alloc_conversion (ck_aggr);
924 c->user_conv_p = true;
929 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
930 array type, if such a conversion is possible. */
933 build_array_conv (tree type, tree ctor, int flags)
936 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
937 tree elttype = TREE_TYPE (type);
942 enum conversion_rank rank = cr_exact;
944 if (TYPE_DOMAIN (type))
946 unsigned HOST_WIDE_INT alen = tree_low_cst (array_type_nelts_top (type), 1);
951 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
954 = implicit_conversion (elttype, TREE_TYPE (val), val,
959 if (sub->rank > rank)
961 if (sub->user_conv_p)
967 c = alloc_conversion (ck_aggr);
970 c->user_conv_p = user;
976 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
977 complex type, if such a conversion is possible. */
980 build_complex_conv (tree type, tree ctor, int flags)
983 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
984 tree elttype = TREE_TYPE (type);
989 enum conversion_rank rank = cr_exact;
994 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
997 = implicit_conversion (elttype, TREE_TYPE (val), val,
1002 if (sub->rank > rank)
1004 if (sub->user_conv_p)
1010 c = alloc_conversion (ck_aggr);
1013 c->user_conv_p = user;
1019 /* Build a representation of the identity conversion from EXPR to
1020 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1023 build_identity_conv (tree type, tree expr)
1027 c = alloc_conversion (ck_identity);
1034 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1035 were multiple user-defined conversions to accomplish the job.
1036 Build a conversion that indicates that ambiguity. */
1039 build_ambiguous_conv (tree type, tree expr)
1043 c = alloc_conversion (ck_ambig);
1051 strip_top_quals (tree t)
1053 if (TREE_CODE (t) == ARRAY_TYPE)
1055 return cp_build_qualified_type (t, 0);
1058 /* Returns the standard conversion path (see [conv]) from type FROM to type
1059 TO, if any. For proper handling of null pointer constants, you must
1060 also pass the expression EXPR to convert from. If C_CAST_P is true,
1061 this conversion is coming from a C-style cast. */
1064 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
1067 enum tree_code fcode, tcode;
1069 bool fromref = false;
1072 to = non_reference (to);
1073 if (TREE_CODE (from) == REFERENCE_TYPE)
1076 from = TREE_TYPE (from);
1079 to = strip_top_quals (to);
1080 from = strip_top_quals (from);
1082 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
1083 && expr && type_unknown_p (expr))
1085 tsubst_flags_t tflags = tf_conv;
1086 if (!(flags & LOOKUP_PROTECT))
1087 tflags |= tf_no_access_control;
1088 expr = instantiate_type (to, expr, tflags);
1089 if (expr == error_mark_node)
1091 from = TREE_TYPE (expr);
1094 fcode = TREE_CODE (from);
1095 tcode = TREE_CODE (to);
1097 conv = build_identity_conv (from, expr);
1098 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
1100 from = type_decays_to (from);
1101 fcode = TREE_CODE (from);
1102 conv = build_conv (ck_lvalue, from, conv);
1104 else if (fromref || (expr && lvalue_p (expr)))
1109 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
1112 from = strip_top_quals (bitfield_type);
1113 fcode = TREE_CODE (from);
1116 conv = build_conv (ck_rvalue, from, conv);
1117 if (flags & LOOKUP_PREFER_RVALUE)
1118 conv->rvaluedness_matches_p = true;
1121 /* Allow conversion between `__complex__' data types. */
1122 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
1124 /* The standard conversion sequence to convert FROM to TO is
1125 the standard conversion sequence to perform componentwise
1127 conversion *part_conv = standard_conversion
1128 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
1132 conv = build_conv (part_conv->kind, to, conv);
1133 conv->rank = part_conv->rank;
1141 if (same_type_p (from, to))
1143 if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue)
1144 conv->type = qualified_to;
1149 A null pointer constant can be converted to a pointer type; ... A
1150 null pointer constant of integral type can be converted to an
1151 rvalue of type std::nullptr_t. */
1152 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to)
1153 || NULLPTR_TYPE_P (to))
1154 && expr && null_ptr_cst_p (expr))
1155 conv = build_conv (ck_std, to, conv);
1156 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
1157 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
1159 /* For backwards brain damage compatibility, allow interconversion of
1160 pointers and integers with a pedwarn. */
1161 conv = build_conv (ck_std, to, conv);
1164 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
1166 /* For backwards brain damage compatibility, allow interconversion of
1167 enums and integers with a pedwarn. */
1168 conv = build_conv (ck_std, to, conv);
1171 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
1172 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
1177 if (tcode == POINTER_TYPE
1178 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
1181 else if (VOID_TYPE_P (TREE_TYPE (to))
1182 && !TYPE_PTRMEM_P (from)
1183 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
1185 tree nfrom = TREE_TYPE (from);
1186 from = build_pointer_type
1187 (cp_build_qualified_type (void_type_node,
1188 cp_type_quals (nfrom)));
1189 conv = build_conv (ck_ptr, from, conv);
1191 else if (TYPE_PTRMEM_P (from))
1193 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
1194 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
1196 if (DERIVED_FROM_P (fbase, tbase)
1197 && (same_type_ignoring_top_level_qualifiers_p
1198 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
1199 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
1201 from = build_ptrmem_type (tbase,
1202 TYPE_PTRMEM_POINTED_TO_TYPE (from));
1203 conv = build_conv (ck_pmem, from, conv);
1205 else if (!same_type_p (fbase, tbase))
1208 else if (CLASS_TYPE_P (TREE_TYPE (from))
1209 && CLASS_TYPE_P (TREE_TYPE (to))
1212 An rvalue of type "pointer to cv D," where D is a
1213 class type, can be converted to an rvalue of type
1214 "pointer to cv B," where B is a base class (clause
1215 _class.derived_) of D. If B is an inaccessible
1216 (clause _class.access_) or ambiguous
1217 (_class.member.lookup_) base class of D, a program
1218 that necessitates this conversion is ill-formed.
1219 Therefore, we use DERIVED_FROM_P, and do not check
1220 access or uniqueness. */
1221 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
1224 cp_build_qualified_type (TREE_TYPE (to),
1225 cp_type_quals (TREE_TYPE (from)));
1226 from = build_pointer_type (from);
1227 conv = build_conv (ck_ptr, from, conv);
1228 conv->base_p = true;
1231 if (tcode == POINTER_TYPE)
1233 to_pointee = TREE_TYPE (to);
1234 from_pointee = TREE_TYPE (from);
1238 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
1239 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
1242 if (same_type_p (from, to))
1244 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
1245 /* In a C-style cast, we ignore CV-qualification because we
1246 are allowed to perform a static_cast followed by a
1248 conv = build_conv (ck_qual, to, conv);
1249 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
1250 conv = build_conv (ck_qual, to, conv);
1251 else if (expr && string_conv_p (to, expr, 0))
1252 /* converting from string constant to char *. */
1253 conv = build_conv (ck_qual, to, conv);
1254 /* Allow conversions among compatible ObjC pointer types (base
1255 conversions have been already handled above). */
1256 else if (c_dialect_objc ()
1257 && objc_compare_types (to, from, -4, NULL_TREE))
1258 conv = build_conv (ck_ptr, to, conv);
1259 else if (ptr_reasonably_similar (to_pointee, from_pointee))
1261 conv = build_conv (ck_ptr, to, conv);
1269 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
1271 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
1272 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
1273 tree fbase = class_of_this_parm (fromfn);
1274 tree tbase = class_of_this_parm (tofn);
1276 if (!DERIVED_FROM_P (fbase, tbase)
1277 || !same_type_p (static_fn_type (fromfn),
1278 static_fn_type (tofn)))
1281 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
1282 from = build_ptrmemfunc_type (build_pointer_type (from));
1283 conv = build_conv (ck_pmem, from, conv);
1284 conv->base_p = true;
1286 else if (tcode == BOOLEAN_TYPE)
1290 An rvalue of arithmetic, unscoped enumeration, pointer, or
1291 pointer to member type can be converted to an rvalue of type
1292 bool. ... An rvalue of type std::nullptr_t can be converted
1293 to an rvalue of type bool; */
1294 if (ARITHMETIC_TYPE_P (from)
1295 || UNSCOPED_ENUM_P (from)
1296 || fcode == POINTER_TYPE
1297 || TYPE_PTR_TO_MEMBER_P (from)
1298 || NULLPTR_TYPE_P (from))
1300 conv = build_conv (ck_std, to, conv);
1301 if (fcode == POINTER_TYPE
1302 || TYPE_PTRMEM_P (from)
1303 || (TYPE_PTRMEMFUNC_P (from)
1304 && conv->rank < cr_pbool)
1305 || NULLPTR_TYPE_P (from))
1306 conv->rank = cr_pbool;
1312 /* We don't check for ENUMERAL_TYPE here because there are no standard
1313 conversions to enum type. */
1314 /* As an extension, allow conversion to complex type. */
1315 else if (ARITHMETIC_TYPE_P (to))
1317 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
1318 || SCOPED_ENUM_P (from))
1320 conv = build_conv (ck_std, to, conv);
1322 /* Give this a better rank if it's a promotion. */
1323 if (same_type_p (to, type_promotes_to (from))
1324 && conv->u.next->rank <= cr_promotion)
1325 conv->rank = cr_promotion;
1327 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
1328 && vector_types_convertible_p (from, to, false))
1329 return build_conv (ck_std, to, conv);
1330 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
1331 && is_properly_derived_from (from, to))
1333 if (conv->kind == ck_rvalue)
1334 conv = conv->u.next;
1335 conv = build_conv (ck_base, to, conv);
1336 /* The derived-to-base conversion indicates the initialization
1337 of a parameter with base type from an object of a derived
1338 type. A temporary object is created to hold the result of
1339 the conversion unless we're binding directly to a reference. */
1340 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
1345 if (flags & LOOKUP_NO_NARROWING)
1346 conv->check_narrowing = true;
1351 /* Returns nonzero if T1 is reference-related to T2. */
1354 reference_related_p (tree t1, tree t2)
1356 if (t1 == error_mark_node || t2 == error_mark_node)
1359 t1 = TYPE_MAIN_VARIANT (t1);
1360 t2 = TYPE_MAIN_VARIANT (t2);
1364 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1365 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1367 return (same_type_p (t1, t2)
1368 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1369 && DERIVED_FROM_P (t1, t2)));
1372 /* Returns nonzero if T1 is reference-compatible with T2. */
1375 reference_compatible_p (tree t1, tree t2)
1379 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1380 reference-related to T2 and cv1 is the same cv-qualification as,
1381 or greater cv-qualification than, cv2. */
1382 return (reference_related_p (t1, t2)
1383 && at_least_as_qualified_p (t1, t2));
1386 /* A reference of the indicated TYPE is being bound directly to the
1387 expression represented by the implicit conversion sequence CONV.
1388 Return a conversion sequence for this binding. */
1391 direct_reference_binding (tree type, conversion *conv)
1395 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1396 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1398 t = TREE_TYPE (type);
1402 When a parameter of reference type binds directly
1403 (_dcl.init.ref_) to an argument expression, the implicit
1404 conversion sequence is the identity conversion, unless the
1405 argument expression has a type that is a derived class of the
1406 parameter type, in which case the implicit conversion sequence is
1407 a derived-to-base Conversion.
1409 If the parameter binds directly to the result of applying a
1410 conversion function to the argument expression, the implicit
1411 conversion sequence is a user-defined conversion sequence
1412 (_over.ics.user_), with the second standard conversion sequence
1413 either an identity conversion or, if the conversion function
1414 returns an entity of a type that is a derived class of the
1415 parameter type, a derived-to-base conversion. */
1416 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1418 /* Represent the derived-to-base conversion. */
1419 conv = build_conv (ck_base, t, conv);
1420 /* We will actually be binding to the base-class subobject in
1421 the derived class, so we mark this conversion appropriately.
1422 That way, convert_like knows not to generate a temporary. */
1423 conv->need_temporary_p = false;
1425 return build_conv (ck_ref_bind, type, conv);
1428 /* Returns the conversion path from type FROM to reference type TO for
1429 purposes of reference binding. For lvalue binding, either pass a
1430 reference type to FROM or an lvalue expression to EXPR. If the
1431 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1432 the conversion returned. If C_CAST_P is true, this
1433 conversion is coming from a C-style cast. */
1436 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1438 conversion *conv = NULL;
1439 tree to = TREE_TYPE (rto);
1444 cp_lvalue_kind gl_kind;
1447 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1449 expr = instantiate_type (to, expr, tf_none);
1450 if (expr == error_mark_node)
1452 from = TREE_TYPE (expr);
1455 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1457 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1458 conv = implicit_conversion (to, from, expr, c_cast_p,
1460 if (!CLASS_TYPE_P (to)
1461 && CONSTRUCTOR_NELTS (expr) == 1)
1463 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1464 if (error_operand_p (expr))
1466 from = TREE_TYPE (expr);
1470 if (TREE_CODE (from) == REFERENCE_TYPE)
1472 from = TREE_TYPE (from);
1473 if (!TYPE_REF_IS_RVALUE (rfrom)
1474 || TREE_CODE (from) == FUNCTION_TYPE)
1475 gl_kind = clk_ordinary;
1477 gl_kind = clk_rvalueref;
1481 gl_kind = lvalue_kind (expr);
1482 if (gl_kind & clk_class)
1483 /* A class prvalue is not a glvalue. */
1488 is_lvalue = gl_kind && !(gl_kind & clk_rvalueref);
1491 if ((gl_kind & clk_bitfield) != 0)
1492 tfrom = unlowered_expr_type (expr);
1494 /* Figure out whether or not the types are reference-related and
1495 reference compatible. We have do do this after stripping
1496 references from FROM. */
1497 related_p = reference_related_p (to, tfrom);
1498 /* If this is a C cast, first convert to an appropriately qualified
1499 type, so that we can later do a const_cast to the desired type. */
1500 if (related_p && c_cast_p
1501 && !at_least_as_qualified_p (to, tfrom))
1502 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1503 compatible_p = reference_compatible_p (to, tfrom);
1505 /* Directly bind reference when target expression's type is compatible with
1506 the reference and expression is an lvalue. In DR391, the wording in
1507 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1508 const and rvalue references to rvalues of compatible class type.
1509 We should also do direct bindings for non-class xvalues. */
1512 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1513 && !(flags & LOOKUP_NO_RVAL_BIND))
1514 || TYPE_REF_IS_RVALUE (rto))
1516 || (!(flags & LOOKUP_NO_TEMP_BIND)
1517 && (CLASS_TYPE_P (from)
1518 || TREE_CODE (from) == ARRAY_TYPE))))))
1522 If the initializer expression
1524 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1525 is reference-compatible with "cv2 T2,"
1527 the reference is bound directly to the initializer expression
1531 If the initializer expression is an rvalue, with T2 a class type,
1532 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1533 is bound to the object represented by the rvalue or to a sub-object
1534 within that object. */
1536 conv = build_identity_conv (tfrom, expr);
1537 conv = direct_reference_binding (rto, conv);
1539 if (flags & LOOKUP_PREFER_RVALUE)
1540 /* The top-level caller requested that we pretend that the lvalue
1541 be treated as an rvalue. */
1542 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1543 else if (TREE_CODE (rfrom) == REFERENCE_TYPE)
1544 /* Handle rvalue reference to function properly. */
1545 conv->rvaluedness_matches_p
1546 = (TYPE_REF_IS_RVALUE (rto) == TYPE_REF_IS_RVALUE (rfrom));
1548 conv->rvaluedness_matches_p
1549 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1551 if ((gl_kind & clk_bitfield) != 0
1552 || ((gl_kind & clk_packed) != 0 && !TYPE_PACKED (to)))
1553 /* For the purposes of overload resolution, we ignore the fact
1554 this expression is a bitfield or packed field. (In particular,
1555 [over.ics.ref] says specifically that a function with a
1556 non-const reference parameter is viable even if the
1557 argument is a bitfield.)
1559 However, when we actually call the function we must create
1560 a temporary to which to bind the reference. If the
1561 reference is volatile, or isn't const, then we cannot make
1562 a temporary, so we just issue an error when the conversion
1564 conv->need_temporary_p = true;
1566 /* Don't allow binding of lvalues (other than function lvalues) to
1567 rvalue references. */
1568 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1569 && TREE_CODE (to) != FUNCTION_TYPE
1570 && !(flags & LOOKUP_PREFER_RVALUE))
1575 /* [class.conv.fct] A conversion function is never used to convert a
1576 (possibly cv-qualified) object to the (possibly cv-qualified) same
1577 object type (or a reference to it), to a (possibly cv-qualified) base
1578 class of that type (or a reference to it).... */
1579 else if (CLASS_TYPE_P (from) && !related_p
1580 && !(flags & LOOKUP_NO_CONVERSION))
1584 If the initializer expression
1586 -- has a class type (i.e., T2 is a class type) can be
1587 implicitly converted to an lvalue of type "cv3 T3," where
1588 "cv1 T1" is reference-compatible with "cv3 T3". (this
1589 conversion is selected by enumerating the applicable
1590 conversion functions (_over.match.ref_) and choosing the
1591 best one through overload resolution. (_over.match_).
1593 the reference is bound to the lvalue result of the conversion
1594 in the second case. */
1595 z_candidate *cand = build_user_type_conversion_1 (rto, expr, flags);
1597 return cand->second_conv;
1600 /* From this point on, we conceptually need temporaries, even if we
1601 elide them. Only the cases above are "direct bindings". */
1602 if (flags & LOOKUP_NO_TEMP_BIND)
1607 When a parameter of reference type is not bound directly to an
1608 argument expression, the conversion sequence is the one required
1609 to convert the argument expression to the underlying type of the
1610 reference according to _over.best.ics_. Conceptually, this
1611 conversion sequence corresponds to copy-initializing a temporary
1612 of the underlying type with the argument expression. Any
1613 difference in top-level cv-qualification is subsumed by the
1614 initialization itself and does not constitute a conversion. */
1618 Otherwise, the reference shall be to a non-volatile const type.
1620 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1621 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1626 Otherwise, a temporary of type "cv1 T1" is created and
1627 initialized from the initializer expression using the rules for a
1628 non-reference copy initialization. If T1 is reference-related to
1629 T2, cv1 must be the same cv-qualification as, or greater
1630 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1631 if (related_p && !at_least_as_qualified_p (to, from))
1634 /* We're generating a temporary now, but don't bind any more in the
1635 conversion (specifically, don't slice the temporary returned by a
1636 conversion operator). */
1637 flags |= LOOKUP_NO_TEMP_BIND;
1639 /* Core issue 899: When [copy-]initializing a temporary to be bound
1640 to the first parameter of a copy constructor (12.8) called with
1641 a single argument in the context of direct-initialization,
1642 explicit conversion functions are also considered.
1644 So don't set LOOKUP_ONLYCONVERTING in that case. */
1645 if (!(flags & LOOKUP_COPY_PARM))
1646 flags |= LOOKUP_ONLYCONVERTING;
1649 conv = implicit_conversion (to, from, expr, c_cast_p,
1654 conv = build_conv (ck_ref_bind, rto, conv);
1655 /* This reference binding, unlike those above, requires the
1656 creation of a temporary. */
1657 conv->need_temporary_p = true;
1658 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1663 /* Returns the implicit conversion sequence (see [over.ics]) from type
1664 FROM to type TO. The optional expression EXPR may affect the
1665 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1666 true, this conversion is coming from a C-style cast. */
1669 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1674 if (from == error_mark_node || to == error_mark_node
1675 || expr == error_mark_node)
1678 /* Other flags only apply to the primary function in overload
1679 resolution, or after we've chosen one. */
1680 flags &= (LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION|LOOKUP_COPY_PARM
1681 |LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND|LOOKUP_PREFER_RVALUE
1682 |LOOKUP_NO_NARROWING|LOOKUP_PROTECT);
1684 if (TREE_CODE (to) == REFERENCE_TYPE)
1685 conv = reference_binding (to, from, expr, c_cast_p, flags);
1687 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1692 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1694 if (is_std_init_list (to))
1695 return build_list_conv (to, expr, flags);
1697 /* As an extension, allow list-initialization of _Complex. */
1698 if (TREE_CODE (to) == COMPLEX_TYPE)
1700 conv = build_complex_conv (to, expr, flags);
1705 /* Allow conversion from an initializer-list with one element to a
1707 if (SCALAR_TYPE_P (to))
1709 int nelts = CONSTRUCTOR_NELTS (expr);
1713 elt = build_value_init (to, tf_none);
1714 else if (nelts == 1)
1715 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1717 elt = error_mark_node;
1719 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1723 conv->check_narrowing = true;
1724 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1725 /* Too many levels of braces, i.e. '{{1}}'. */
1730 else if (TREE_CODE (to) == ARRAY_TYPE)
1731 return build_array_conv (to, expr, flags);
1734 if (expr != NULL_TREE
1735 && (MAYBE_CLASS_TYPE_P (from)
1736 || MAYBE_CLASS_TYPE_P (to))
1737 && (flags & LOOKUP_NO_CONVERSION) == 0)
1739 struct z_candidate *cand;
1741 if (CLASS_TYPE_P (to)
1742 && BRACE_ENCLOSED_INITIALIZER_P (expr)
1743 && !CLASSTYPE_NON_AGGREGATE (complete_type (to)))
1744 return build_aggr_conv (to, expr, flags);
1746 cand = build_user_type_conversion_1 (to, expr, flags);
1748 conv = cand->second_conv;
1750 /* We used to try to bind a reference to a temporary here, but that
1751 is now handled after the recursive call to this function at the end
1752 of reference_binding. */
1759 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1760 functions. ARGS will not be changed until a single candidate is
1763 static struct z_candidate *
1764 add_candidate (struct z_candidate **candidates,
1765 tree fn, tree first_arg, const VEC(tree,gc) *args,
1766 size_t num_convs, conversion **convs,
1767 tree access_path, tree conversion_path,
1768 int viable, struct rejection_reason *reason)
1770 struct z_candidate *cand = (struct z_candidate *)
1771 conversion_obstack_alloc (sizeof (struct z_candidate));
1774 cand->first_arg = first_arg;
1776 cand->convs = convs;
1777 cand->num_convs = num_convs;
1778 cand->access_path = access_path;
1779 cand->conversion_path = conversion_path;
1780 cand->viable = viable;
1781 cand->reason = reason;
1782 cand->next = *candidates;
1788 /* Return the number of remaining arguments in the parameter list
1789 beginning with ARG. */
1792 remaining_arguments (tree arg)
1796 for (n = 0; arg != NULL_TREE && arg != void_list_node;
1797 arg = TREE_CHAIN (arg))
1803 /* Create an overload candidate for the function or method FN called
1804 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1805 FLAGS is passed on to implicit_conversion.
1807 This does not change ARGS.
1809 CTYPE, if non-NULL, is the type we want to pretend this function
1810 comes from for purposes of overload resolution. */
1812 static struct z_candidate *
1813 add_function_candidate (struct z_candidate **candidates,
1814 tree fn, tree ctype, tree first_arg,
1815 const VEC(tree,gc) *args, tree access_path,
1816 tree conversion_path, int flags)
1818 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1822 tree orig_first_arg = first_arg;
1825 struct rejection_reason *reason = NULL;
1827 /* At this point we should not see any functions which haven't been
1828 explicitly declared, except for friend functions which will have
1829 been found using argument dependent lookup. */
1830 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1832 /* The `this', `in_chrg' and VTT arguments to constructors are not
1833 considered in overload resolution. */
1834 if (DECL_CONSTRUCTOR_P (fn))
1836 parmlist = skip_artificial_parms_for (fn, parmlist);
1837 skip = num_artificial_parms_for (fn);
1838 if (skip > 0 && first_arg != NULL_TREE)
1841 first_arg = NULL_TREE;
1847 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1848 convs = alloc_conversions (len);
1850 /* 13.3.2 - Viable functions [over.match.viable]
1851 First, to be a viable function, a candidate function shall have enough
1852 parameters to agree in number with the arguments in the list.
1854 We need to check this first; otherwise, checking the ICSes might cause
1855 us to produce an ill-formed template instantiation. */
1857 parmnode = parmlist;
1858 for (i = 0; i < len; ++i)
1860 if (parmnode == NULL_TREE || parmnode == void_list_node)
1862 parmnode = TREE_CHAIN (parmnode);
1865 if ((i < len && parmnode)
1866 || !sufficient_parms_p (parmnode))
1868 int remaining = remaining_arguments (parmnode);
1870 reason = arity_rejection (first_arg, i + remaining, len);
1872 /* When looking for a function from a subobject from an implicit
1873 copy/move constructor/operator=, don't consider anything that takes (a
1874 reference to) an unrelated type. See c++/44909 and core 1092. */
1875 else if (parmlist && (flags & LOOKUP_DEFAULTED))
1877 if (DECL_CONSTRUCTOR_P (fn))
1879 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
1880 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
1886 parmnode = chain_index (i-1, parmlist);
1887 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
1892 /* This only applies at the top level. */
1893 flags &= ~LOOKUP_DEFAULTED;
1899 /* Second, for F to be a viable function, there shall exist for each
1900 argument an implicit conversion sequence that converts that argument
1901 to the corresponding parameter of F. */
1903 parmnode = parmlist;
1905 for (i = 0; i < len; ++i)
1907 tree arg, argtype, to_type;
1911 if (parmnode == void_list_node)
1914 if (i == 0 && first_arg != NULL_TREE)
1917 arg = VEC_index (tree, args,
1918 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1919 argtype = lvalue_type (arg);
1921 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1922 && ! DECL_CONSTRUCTOR_P (fn));
1926 tree parmtype = TREE_VALUE (parmnode);
1929 parmnode = TREE_CHAIN (parmnode);
1931 /* The type of the implicit object parameter ('this') for
1932 overload resolution is not always the same as for the
1933 function itself; conversion functions are considered to
1934 be members of the class being converted, and functions
1935 introduced by a using-declaration are considered to be
1936 members of the class that uses them.
1938 Since build_over_call ignores the ICS for the `this'
1939 parameter, we can just change the parm type. */
1940 if (ctype && is_this)
1942 parmtype = cp_build_qualified_type
1943 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
1944 parmtype = build_pointer_type (parmtype);
1947 /* Core issue 899: When [copy-]initializing a temporary to be bound
1948 to the first parameter of a copy constructor (12.8) called with
1949 a single argument in the context of direct-initialization,
1950 explicit conversion functions are also considered.
1952 So set LOOKUP_COPY_PARM to let reference_binding know that
1953 it's being called in that context. We generalize the above
1954 to handle move constructors and template constructors as well;
1955 the standardese should soon be updated similarly. */
1956 if (ctype && i == 0 && (len-skip == 1)
1957 && DECL_CONSTRUCTOR_P (fn)
1958 && parmtype != error_mark_node
1959 && (same_type_ignoring_top_level_qualifiers_p
1960 (non_reference (parmtype), ctype)))
1962 if (!(flags & LOOKUP_ONLYCONVERTING))
1963 lflags |= LOOKUP_COPY_PARM;
1964 /* We allow user-defined conversions within init-lists, but
1965 don't list-initialize the copy parm, as that would mean
1966 using two levels of braces for the same type. */
1967 if ((flags & LOOKUP_LIST_INIT_CTOR)
1968 && BRACE_ENCLOSED_INITIALIZER_P (arg))
1969 lflags |= LOOKUP_NO_CONVERSION;
1972 lflags |= LOOKUP_ONLYCONVERTING;
1974 t = implicit_conversion (parmtype, argtype, arg,
1975 /*c_cast_p=*/false, lflags);
1980 t = build_identity_conv (argtype, arg);
1981 t->ellipsis_p = true;
1992 reason = arg_conversion_rejection (first_arg, i, argtype, to_type);
1999 reason = bad_arg_conversion_rejection (first_arg, i, argtype, to_type);
2004 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
2005 access_path, conversion_path, viable, reason);
2008 /* Create an overload candidate for the conversion function FN which will
2009 be invoked for expression OBJ, producing a pointer-to-function which
2010 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2011 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2012 passed on to implicit_conversion.
2014 Actually, we don't really care about FN; we care about the type it
2015 converts to. There may be multiple conversion functions that will
2016 convert to that type, and we rely on build_user_type_conversion_1 to
2017 choose the best one; so when we create our candidate, we record the type
2018 instead of the function. */
2020 static struct z_candidate *
2021 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
2022 tree first_arg, const VEC(tree,gc) *arglist,
2023 tree access_path, tree conversion_path)
2025 tree totype = TREE_TYPE (TREE_TYPE (fn));
2026 int i, len, viable, flags;
2027 tree parmlist, parmnode;
2029 struct rejection_reason *reason;
2031 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
2032 parmlist = TREE_TYPE (parmlist);
2033 parmlist = TYPE_ARG_TYPES (parmlist);
2035 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
2036 convs = alloc_conversions (len);
2037 parmnode = parmlist;
2039 flags = LOOKUP_IMPLICIT;
2042 /* Don't bother looking up the same type twice. */
2043 if (*candidates && (*candidates)->fn == totype)
2046 for (i = 0; i < len; ++i)
2048 tree arg, argtype, convert_type = NULL_TREE;
2053 else if (i == 1 && first_arg != NULL_TREE)
2056 arg = VEC_index (tree, arglist,
2057 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
2058 argtype = lvalue_type (arg);
2062 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
2064 convert_type = totype;
2066 else if (parmnode == void_list_node)
2070 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
2071 /*c_cast_p=*/false, flags);
2072 convert_type = TREE_VALUE (parmnode);
2076 t = build_identity_conv (argtype, arg);
2077 t->ellipsis_p = true;
2078 convert_type = argtype;
2088 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtype, convert_type);
2095 parmnode = TREE_CHAIN (parmnode);
2099 || ! sufficient_parms_p (parmnode))
2101 int remaining = remaining_arguments (parmnode);
2103 reason = arity_rejection (NULL_TREE, i + remaining, len);
2106 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
2107 access_path, conversion_path, viable, reason);
2111 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
2112 tree type1, tree type2, tree *args, tree *argtypes,
2120 struct rejection_reason *reason = NULL;
2125 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
2126 convs = alloc_conversions (num_convs);
2128 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2129 conversion ops are allowed. We handle that here by just checking for
2130 boolean_type_node because other operators don't ask for it. COND_EXPR
2131 also does contextual conversion to bool for the first operand, but we
2132 handle that in build_conditional_expr, and type1 here is operand 2. */
2133 if (type1 != boolean_type_node)
2134 flags |= LOOKUP_ONLYCONVERTING;
2136 for (i = 0; i < 2; ++i)
2141 t = implicit_conversion (types[i], argtypes[i], args[i],
2142 /*c_cast_p=*/false, flags);
2146 /* We need something for printing the candidate. */
2147 t = build_identity_conv (types[i], NULL_TREE);
2148 reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2153 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2158 /* For COND_EXPR we rearranged the arguments; undo that now. */
2161 convs[2] = convs[1];
2162 convs[1] = convs[0];
2163 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
2164 /*c_cast_p=*/false, flags);
2170 reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2],
2175 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
2177 /*access_path=*/NULL_TREE,
2178 /*conversion_path=*/NULL_TREE,
2183 is_complete (tree t)
2185 return COMPLETE_TYPE_P (complete_type (t));
2188 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2191 promoted_arithmetic_type_p (tree type)
2195 In this section, the term promoted integral type is used to refer
2196 to those integral types which are preserved by integral promotion
2197 (including e.g. int and long but excluding e.g. char).
2198 Similarly, the term promoted arithmetic type refers to promoted
2199 integral types plus floating types. */
2200 return ((CP_INTEGRAL_TYPE_P (type)
2201 && same_type_p (type_promotes_to (type), type))
2202 || TREE_CODE (type) == REAL_TYPE);
2205 /* Create any builtin operator overload candidates for the operator in
2206 question given the converted operand types TYPE1 and TYPE2. The other
2207 args are passed through from add_builtin_candidates to
2208 build_builtin_candidate.
2210 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2211 If CODE is requires candidates operands of the same type of the kind
2212 of which TYPE1 and TYPE2 are, we add both candidates
2213 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2216 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
2217 enum tree_code code2, tree fnname, tree type1,
2218 tree type2, tree *args, tree *argtypes, int flags)
2222 case POSTINCREMENT_EXPR:
2223 case POSTDECREMENT_EXPR:
2224 args[1] = integer_zero_node;
2225 type2 = integer_type_node;
2234 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2235 and VQ is either volatile or empty, there exist candidate operator
2236 functions of the form
2237 VQ T& operator++(VQ T&);
2238 T operator++(VQ T&, int);
2239 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2240 type other than bool, and VQ is either volatile or empty, there exist
2241 candidate operator functions of the form
2242 VQ T& operator--(VQ T&);
2243 T operator--(VQ T&, int);
2244 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2245 complete object type, and VQ is either volatile or empty, there exist
2246 candidate operator functions of the form
2247 T*VQ& operator++(T*VQ&);
2248 T*VQ& operator--(T*VQ&);
2249 T* operator++(T*VQ&, int);
2250 T* operator--(T*VQ&, int); */
2252 case POSTDECREMENT_EXPR:
2253 case PREDECREMENT_EXPR:
2254 if (TREE_CODE (type1) == BOOLEAN_TYPE)
2256 case POSTINCREMENT_EXPR:
2257 case PREINCREMENT_EXPR:
2258 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
2260 type1 = build_reference_type (type1);
2265 /* 7 For every cv-qualified or cv-unqualified object type T, there
2266 exist candidate operator functions of the form
2270 8 For every function type T, there exist candidate operator functions of
2272 T& operator*(T*); */
2275 if (TREE_CODE (type1) == POINTER_TYPE
2276 && !uses_template_parms (TREE_TYPE (type1))
2277 && (TYPE_PTROB_P (type1)
2278 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
2282 /* 9 For every type T, there exist candidate operator functions of the form
2285 10For every promoted arithmetic type T, there exist candidate operator
2286 functions of the form
2290 case UNARY_PLUS_EXPR: /* unary + */
2291 if (TREE_CODE (type1) == POINTER_TYPE)
2294 if (ARITHMETIC_TYPE_P (type1))
2298 /* 11For every promoted integral type T, there exist candidate operator
2299 functions of the form
2303 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2307 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2308 is the same type as C2 or is a derived class of C2, T is a complete
2309 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2310 there exist candidate operator functions of the form
2311 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2312 where CV12 is the union of CV1 and CV2. */
2315 if (TREE_CODE (type1) == POINTER_TYPE
2316 && TYPE_PTR_TO_MEMBER_P (type2))
2318 tree c1 = TREE_TYPE (type1);
2319 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2321 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2322 && (TYPE_PTRMEMFUNC_P (type2)
2323 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2328 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2329 didate operator functions of the form
2334 bool operator<(L, R);
2335 bool operator>(L, R);
2336 bool operator<=(L, R);
2337 bool operator>=(L, R);
2338 bool operator==(L, R);
2339 bool operator!=(L, R);
2340 where LR is the result of the usual arithmetic conversions between
2343 14For every pair of types T and I, where T is a cv-qualified or cv-
2344 unqualified complete object type and I is a promoted integral type,
2345 there exist candidate operator functions of the form
2346 T* operator+(T*, I);
2347 T& operator[](T*, I);
2348 T* operator-(T*, I);
2349 T* operator+(I, T*);
2350 T& operator[](I, T*);
2352 15For every T, where T is a pointer to complete object type, there exist
2353 candidate operator functions of the form112)
2354 ptrdiff_t operator-(T, T);
2356 16For every pointer or enumeration type T, there exist candidate operator
2357 functions of the form
2358 bool operator<(T, T);
2359 bool operator>(T, T);
2360 bool operator<=(T, T);
2361 bool operator>=(T, T);
2362 bool operator==(T, T);
2363 bool operator!=(T, T);
2365 17For every pointer to member type T, there exist candidate operator
2366 functions of the form
2367 bool operator==(T, T);
2368 bool operator!=(T, T); */
2371 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2373 if (TYPE_PTROB_P (type1)
2374 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2376 type2 = ptrdiff_type_node;
2380 case TRUNC_DIV_EXPR:
2381 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2387 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2388 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2390 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2395 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2407 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2409 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2411 if (TREE_CODE (type1) == ENUMERAL_TYPE
2412 && TREE_CODE (type2) == ENUMERAL_TYPE)
2414 if (TYPE_PTR_P (type1)
2415 && null_ptr_cst_p (args[1])
2416 && !uses_template_parms (type1))
2421 if (null_ptr_cst_p (args[0])
2422 && TYPE_PTR_P (type2)
2423 && !uses_template_parms (type2))
2431 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2434 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2436 type1 = ptrdiff_type_node;
2439 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2441 type2 = ptrdiff_type_node;
2446 /* 18For every pair of promoted integral types L and R, there exist candi-
2447 date operator functions of the form
2454 where LR is the result of the usual arithmetic conversions between
2457 case TRUNC_MOD_EXPR:
2463 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2467 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2468 type, VQ is either volatile or empty, and R is a promoted arithmetic
2469 type, there exist candidate operator functions of the form
2470 VQ L& operator=(VQ L&, R);
2471 VQ L& operator*=(VQ L&, R);
2472 VQ L& operator/=(VQ L&, R);
2473 VQ L& operator+=(VQ L&, R);
2474 VQ L& operator-=(VQ L&, R);
2476 20For every pair T, VQ), where T is any type and VQ is either volatile
2477 or empty, there exist candidate operator functions of the form
2478 T*VQ& operator=(T*VQ&, T*);
2480 21For every pair T, VQ), where T is a pointer to member type and VQ is
2481 either volatile or empty, there exist candidate operator functions of
2483 VQ T& operator=(VQ T&, T);
2485 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2486 unqualified complete object type, VQ is either volatile or empty, and
2487 I is a promoted integral type, there exist candidate operator func-
2489 T*VQ& operator+=(T*VQ&, I);
2490 T*VQ& operator-=(T*VQ&, I);
2492 23For every triple L, VQ, R), where L is an integral or enumeration
2493 type, VQ is either volatile or empty, and R is a promoted integral
2494 type, there exist candidate operator functions of the form
2496 VQ L& operator%=(VQ L&, R);
2497 VQ L& operator<<=(VQ L&, R);
2498 VQ L& operator>>=(VQ L&, R);
2499 VQ L& operator&=(VQ L&, R);
2500 VQ L& operator^=(VQ L&, R);
2501 VQ L& operator|=(VQ L&, R); */
2508 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2510 type2 = ptrdiff_type_node;
2514 case TRUNC_DIV_EXPR:
2515 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2519 case TRUNC_MOD_EXPR:
2525 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2530 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2532 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2533 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2534 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2535 || ((TYPE_PTRMEMFUNC_P (type1)
2536 || TREE_CODE (type1) == POINTER_TYPE)
2537 && null_ptr_cst_p (args[1])))
2547 type1 = build_reference_type (type1);
2553 For every pair of promoted arithmetic types L and R, there
2554 exist candidate operator functions of the form
2556 LR operator?(bool, L, R);
2558 where LR is the result of the usual arithmetic conversions
2559 between types L and R.
2561 For every type T, where T is a pointer or pointer-to-member
2562 type, there exist candidate operator functions of the form T
2563 operator?(bool, T, T); */
2565 if (promoted_arithmetic_type_p (type1)
2566 && promoted_arithmetic_type_p (type2))
2570 /* Otherwise, the types should be pointers. */
2571 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2572 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2575 /* We don't check that the two types are the same; the logic
2576 below will actually create two candidates; one in which both
2577 parameter types are TYPE1, and one in which both parameter
2583 if (ARITHMETIC_TYPE_P (type1))
2591 /* If we're dealing with two pointer types or two enumeral types,
2592 we need candidates for both of them. */
2593 if (type2 && !same_type_p (type1, type2)
2594 && TREE_CODE (type1) == TREE_CODE (type2)
2595 && (TREE_CODE (type1) == REFERENCE_TYPE
2596 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2597 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2598 || TYPE_PTRMEMFUNC_P (type1)
2599 || MAYBE_CLASS_TYPE_P (type1)
2600 || TREE_CODE (type1) == ENUMERAL_TYPE))
2602 if (TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2604 tree cptype = composite_pointer_type (type1, type2,
2609 if (cptype != error_mark_node)
2611 build_builtin_candidate
2612 (candidates, fnname, cptype, cptype, args, argtypes, flags);
2617 build_builtin_candidate
2618 (candidates, fnname, type1, type1, args, argtypes, flags);
2619 build_builtin_candidate
2620 (candidates, fnname, type2, type2, args, argtypes, flags);
2624 build_builtin_candidate
2625 (candidates, fnname, type1, type2, args, argtypes, flags);
2629 type_decays_to (tree type)
2631 if (TREE_CODE (type) == ARRAY_TYPE)
2632 return build_pointer_type (TREE_TYPE (type));
2633 if (TREE_CODE (type) == FUNCTION_TYPE)
2634 return build_pointer_type (type);
2638 /* There are three conditions of builtin candidates:
2640 1) bool-taking candidates. These are the same regardless of the input.
2641 2) pointer-pair taking candidates. These are generated for each type
2642 one of the input types converts to.
2643 3) arithmetic candidates. According to the standard, we should generate
2644 all of these, but I'm trying not to...
2646 Here we generate a superset of the possible candidates for this particular
2647 case. That is a subset of the full set the standard defines, plus some
2648 other cases which the standard disallows. add_builtin_candidate will
2649 filter out the invalid set. */
2652 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2653 enum tree_code code2, tree fnname, tree *args,
2658 tree type, argtypes[3], t;
2659 /* TYPES[i] is the set of possible builtin-operator parameter types
2660 we will consider for the Ith argument. */
2661 VEC(tree,gc) *types[2];
2664 for (i = 0; i < 3; ++i)
2667 argtypes[i] = unlowered_expr_type (args[i]);
2669 argtypes[i] = NULL_TREE;
2674 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2675 and VQ is either volatile or empty, there exist candidate operator
2676 functions of the form
2677 VQ T& operator++(VQ T&); */
2679 case POSTINCREMENT_EXPR:
2680 case PREINCREMENT_EXPR:
2681 case POSTDECREMENT_EXPR:
2682 case PREDECREMENT_EXPR:
2687 /* 24There also exist candidate operator functions of the form
2688 bool operator!(bool);
2689 bool operator&&(bool, bool);
2690 bool operator||(bool, bool); */
2692 case TRUTH_NOT_EXPR:
2693 build_builtin_candidate
2694 (candidates, fnname, boolean_type_node,
2695 NULL_TREE, args, argtypes, flags);
2698 case TRUTH_ORIF_EXPR:
2699 case TRUTH_ANDIF_EXPR:
2700 build_builtin_candidate
2701 (candidates, fnname, boolean_type_node,
2702 boolean_type_node, args, argtypes, flags);
2724 types[0] = make_tree_vector ();
2725 types[1] = make_tree_vector ();
2727 for (i = 0; i < 2; ++i)
2731 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2735 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2738 convs = lookup_conversions (argtypes[i]);
2740 if (code == COND_EXPR)
2742 if (real_lvalue_p (args[i]))
2743 VEC_safe_push (tree, gc, types[i],
2744 build_reference_type (argtypes[i]));
2746 VEC_safe_push (tree, gc, types[i],
2747 TYPE_MAIN_VARIANT (argtypes[i]));
2753 for (; convs; convs = TREE_CHAIN (convs))
2755 type = TREE_TYPE (convs);
2758 && (TREE_CODE (type) != REFERENCE_TYPE
2759 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2762 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2763 VEC_safe_push (tree, gc, types[i], type);
2765 type = non_reference (type);
2766 if (i != 0 || ! ref1)
2768 type = cv_unqualified (type_decays_to (type));
2769 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2770 VEC_safe_push (tree, gc, types[i], type);
2771 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2772 type = type_promotes_to (type);
2775 if (! vec_member (type, types[i]))
2776 VEC_safe_push (tree, gc, types[i], type);
2781 if (code == COND_EXPR && real_lvalue_p (args[i]))
2782 VEC_safe_push (tree, gc, types[i],
2783 build_reference_type (argtypes[i]));
2784 type = non_reference (argtypes[i]);
2785 if (i != 0 || ! ref1)
2787 type = cv_unqualified (type_decays_to (type));
2788 if (enum_p && UNSCOPED_ENUM_P (type))
2789 VEC_safe_push (tree, gc, types[i], type);
2790 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2791 type = type_promotes_to (type);
2793 VEC_safe_push (tree, gc, types[i], type);
2797 /* Run through the possible parameter types of both arguments,
2798 creating candidates with those parameter types. */
2799 FOR_EACH_VEC_ELT_REVERSE (tree, types[0], ix, t)
2804 if (!VEC_empty (tree, types[1]))
2805 FOR_EACH_VEC_ELT_REVERSE (tree, types[1], jx, u)
2806 add_builtin_candidate
2807 (candidates, code, code2, fnname, t,
2808 u, args, argtypes, flags);
2810 add_builtin_candidate
2811 (candidates, code, code2, fnname, t,
2812 NULL_TREE, args, argtypes, flags);
2815 release_tree_vector (types[0]);
2816 release_tree_vector (types[1]);
2820 /* If TMPL can be successfully instantiated as indicated by
2821 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2823 TMPL is the template. EXPLICIT_TARGS are any explicit template
2824 arguments. ARGLIST is the arguments provided at the call-site.
2825 This does not change ARGLIST. The RETURN_TYPE is the desired type
2826 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2827 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2828 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2830 static struct z_candidate*
2831 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2832 tree ctype, tree explicit_targs, tree first_arg,
2833 const VEC(tree,gc) *arglist, tree return_type,
2834 tree access_path, tree conversion_path,
2835 int flags, tree obj, unification_kind_t strict)
2837 int ntparms = DECL_NTPARMS (tmpl);
2838 tree targs = make_tree_vec (ntparms);
2839 unsigned int len = VEC_length (tree, arglist);
2840 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2841 unsigned int skip_without_in_chrg = 0;
2842 tree first_arg_without_in_chrg = first_arg;
2843 tree *args_without_in_chrg;
2844 unsigned int nargs_without_in_chrg;
2845 unsigned int ia, ix;
2847 struct z_candidate *cand;
2850 struct rejection_reason *reason = NULL;
2853 /* We don't do deduction on the in-charge parameter, the VTT
2854 parameter or 'this'. */
2855 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2857 if (first_arg_without_in_chrg != NULL_TREE)
2858 first_arg_without_in_chrg = NULL_TREE;
2860 ++skip_without_in_chrg;
2863 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2864 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2865 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2867 if (first_arg_without_in_chrg != NULL_TREE)
2868 first_arg_without_in_chrg = NULL_TREE;
2870 ++skip_without_in_chrg;
2873 if (len < skip_without_in_chrg)
2876 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2877 + (len - skip_without_in_chrg));
2878 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2880 if (first_arg_without_in_chrg != NULL_TREE)
2882 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2885 for (ix = skip_without_in_chrg;
2886 VEC_iterate (tree, arglist, ix, arg);
2889 args_without_in_chrg[ia] = arg;
2892 gcc_assert (ia == nargs_without_in_chrg);
2894 errs = errorcount+sorrycount;
2895 i = fn_type_unification (tmpl, explicit_targs, targs,
2896 args_without_in_chrg,
2897 nargs_without_in_chrg,
2898 return_type, strict, flags, false);
2902 /* Don't repeat unification later if it already resulted in errors. */
2903 if (errorcount+sorrycount == errs)
2904 reason = template_unification_rejection (tmpl, explicit_targs,
2905 targs, args_without_in_chrg,
2906 nargs_without_in_chrg,
2907 return_type, strict, flags);
2909 reason = template_unification_error_rejection ();
2913 fn = instantiate_template (tmpl, targs, tf_none);
2914 if (fn == error_mark_node)
2916 reason = template_instantiation_rejection (tmpl, targs);
2922 A member function template is never instantiated to perform the
2923 copy of a class object to an object of its class type.
2925 It's a little unclear what this means; the standard explicitly
2926 does allow a template to be used to copy a class. For example,
2931 template <class T> A(const T&);
2934 void g () { A a (f ()); }
2936 the member template will be used to make the copy. The section
2937 quoted above appears in the paragraph that forbids constructors
2938 whose only parameter is (a possibly cv-qualified variant of) the
2939 class type, and a logical interpretation is that the intent was
2940 to forbid the instantiation of member templates which would then
2942 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2944 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2945 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2948 reason = invalid_copy_with_fn_template_rejection ();
2953 if (obj != NULL_TREE)
2954 /* Aha, this is a conversion function. */
2955 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2956 access_path, conversion_path);
2958 cand = add_function_candidate (candidates, fn, ctype,
2959 first_arg, arglist, access_path,
2960 conversion_path, flags);
2961 if (DECL_TI_TEMPLATE (fn) != tmpl)
2962 /* This situation can occur if a member template of a template
2963 class is specialized. Then, instantiate_template might return
2964 an instantiation of the specialization, in which case the
2965 DECL_TI_TEMPLATE field will point at the original
2966 specialization. For example:
2968 template <class T> struct S { template <class U> void f(U);
2969 template <> void f(int) {}; };
2973 Here, TMPL will be template <class U> S<double>::f(U).
2974 And, instantiate template will give us the specialization
2975 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2976 for this will point at template <class T> template <> S<T>::f(int),
2977 so that we can find the definition. For the purposes of
2978 overload resolution, however, we want the original TMPL. */
2979 cand->template_decl = build_template_info (tmpl, targs);
2981 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2982 cand->explicit_targs = explicit_targs;
2986 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
2987 access_path, conversion_path, 0, reason);
2991 static struct z_candidate *
2992 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2993 tree explicit_targs, tree first_arg,
2994 const VEC(tree,gc) *arglist, tree return_type,
2995 tree access_path, tree conversion_path, int flags,
2996 unification_kind_t strict)
2999 add_template_candidate_real (candidates, tmpl, ctype,
3000 explicit_targs, first_arg, arglist,
3001 return_type, access_path, conversion_path,
3002 flags, NULL_TREE, strict);
3006 static struct z_candidate *
3007 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
3008 tree obj, tree first_arg,
3009 const VEC(tree,gc) *arglist,
3010 tree return_type, tree access_path,
3011 tree conversion_path)
3014 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
3015 first_arg, arglist, return_type, access_path,
3016 conversion_path, 0, obj, DEDUCE_CONV);
3019 /* The CANDS are the set of candidates that were considered for
3020 overload resolution. Return the set of viable candidates, or CANDS
3021 if none are viable. If any of the candidates were viable, set
3022 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3023 considered viable only if it is strictly viable. */
3025 static struct z_candidate*
3026 splice_viable (struct z_candidate *cands,
3030 struct z_candidate *viable;
3031 struct z_candidate **last_viable;
3032 struct z_candidate **cand;
3034 /* Be strict inside templates, since build_over_call won't actually
3035 do the conversions to get pedwarns. */
3036 if (processing_template_decl)
3040 last_viable = &viable;
3041 *any_viable_p = false;
3046 struct z_candidate *c = *cand;
3047 if (strict_p ? c->viable == 1 : c->viable)
3052 last_viable = &c->next;
3053 *any_viable_p = true;
3059 return viable ? viable : cands;
3063 any_strictly_viable (struct z_candidate *cands)
3065 for (; cands; cands = cands->next)
3066 if (cands->viable == 1)
3071 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3072 words, it is about to become the "this" pointer for a member
3073 function call. Take the address of the object. */
3076 build_this (tree obj)
3078 /* In a template, we are only concerned about the type of the
3079 expression, so we can take a shortcut. */
3080 if (processing_template_decl)
3081 return build_address (obj);
3083 return cp_build_addr_expr (obj, tf_warning_or_error);
3086 /* Returns true iff functions are equivalent. Equivalent functions are
3087 not '==' only if one is a function-local extern function or if
3088 both are extern "C". */
3091 equal_functions (tree fn1, tree fn2)
3093 if (TREE_CODE (fn1) != TREE_CODE (fn2))
3095 if (TREE_CODE (fn1) == TEMPLATE_DECL)
3097 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
3098 || DECL_EXTERN_C_FUNCTION_P (fn1))
3099 return decls_match (fn1, fn2);
3103 /* Print information about a candidate being rejected due to INFO. */
3106 print_conversion_rejection (location_t loc, struct conversion_info *info)
3108 if (info->n_arg == -1)
3109 /* Conversion of implicit `this' argument failed. */
3110 inform (loc, " no known conversion for implicit "
3111 "%<this%> parameter from %qT to %qT",
3112 info->from_type, info->to_type);
3114 inform (loc, " no known conversion for argument %d from %qT to %qT",
3115 info->n_arg+1, info->from_type, info->to_type);
3118 /* Print information about a candidate with WANT parameters and we found
3122 print_arity_information (location_t loc, unsigned int have, unsigned int want)
3124 inform_n (loc, want,
3125 " candidate expects %d argument, %d provided",
3126 " candidate expects %d arguments, %d provided",
3130 /* Print information about one overload candidate CANDIDATE. MSGSTR
3131 is the text to print before the candidate itself.
3133 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3134 to have been run through gettext by the caller. This wart makes
3135 life simpler in print_z_candidates and for the translators. */
3138 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
3140 const char *msg = (msgstr == NULL
3142 : ACONCAT ((msgstr, " ", NULL)));
3143 location_t loc = location_of (candidate->fn);
3145 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
3147 if (candidate->num_convs == 3)
3148 inform (input_location, "%s%D(%T, %T, %T) <built-in>", msg, candidate->fn,
3149 candidate->convs[0]->type,
3150 candidate->convs[1]->type,
3151 candidate->convs[2]->type);
3152 else if (candidate->num_convs == 2)
3153 inform (input_location, "%s%D(%T, %T) <built-in>", msg, candidate->fn,
3154 candidate->convs[0]->type,
3155 candidate->convs[1]->type);
3157 inform (input_location, "%s%D(%T) <built-in>", msg, candidate->fn,
3158 candidate->convs[0]->type);
3160 else if (TYPE_P (candidate->fn))
3161 inform (input_location, "%s%T <conversion>", msg, candidate->fn);
3162 else if (candidate->viable == -1)
3163 inform (loc, "%s%#D <near match>", msg, candidate->fn);
3164 else if (DECL_DELETED_FN (STRIP_TEMPLATE (candidate->fn)))
3165 inform (loc, "%s%#D <deleted>", msg, candidate->fn);
3167 inform (loc, "%s%#D", msg, candidate->fn);
3168 /* Give the user some information about why this candidate failed. */
3169 if (candidate->reason != NULL)
3171 struct rejection_reason *r = candidate->reason;
3176 print_arity_information (loc, r->u.arity.actual,
3177 r->u.arity.expected);
3179 case rr_arg_conversion:
3180 print_conversion_rejection (loc, &r->u.conversion);
3182 case rr_bad_arg_conversion:
3183 print_conversion_rejection (loc, &r->u.bad_conversion);
3185 case rr_explicit_conversion:
3186 inform (loc, " return type %qT of explicit conversion function "
3187 "cannot be converted to %qT with a qualification "
3188 "conversion", r->u.conversion.from_type,
3189 r->u.conversion.to_type);
3191 case rr_template_conversion:
3192 inform (loc, " conversion from return type %qT of template "
3193 "conversion function specialization to %qT is not an "
3194 "exact match", r->u.conversion.from_type,
3195 r->u.conversion.to_type);
3197 case rr_template_unification:
3198 /* We use template_unification_error_rejection if unification caused
3199 actual non-SFINAE errors, in which case we don't need to repeat
3201 if (r->u.template_unification.tmpl == NULL_TREE)
3203 inform (loc, " substitution of deduced template arguments "
3204 "resulted in errors seen above");
3207 /* Re-run template unification with diagnostics. */
3208 inform (loc, " template argument deduction/substitution failed:");
3209 fn_type_unification (r->u.template_unification.tmpl,
3210 r->u.template_unification.explicit_targs,
3211 r->u.template_unification.targs,
3212 r->u.template_unification.args,
3213 r->u.template_unification.nargs,
3214 r->u.template_unification.return_type,
3215 r->u.template_unification.strict,
3216 r->u.template_unification.flags,
3219 case rr_template_instantiation:
3220 /* Re-run template instantiation with diagnostics. */
3221 instantiate_template (r->u.template_instantiation.tmpl,
3222 r->u.template_instantiation.targs,
3223 tf_warning_or_error);
3225 case rr_invalid_copy:
3227 " a constructor taking a single argument of its own "
3228 "class type is invalid");
3232 /* This candidate didn't have any issues or we failed to
3233 handle a particular code. Either way... */
3240 print_z_candidates (location_t loc, struct z_candidate *candidates)
3242 struct z_candidate *cand1;
3243 struct z_candidate **cand2;
3249 /* Remove non-viable deleted candidates. */
3251 for (cand2 = &cand1; *cand2; )
3253 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
3254 && !(*cand2)->viable
3255 && DECL_DELETED_FN ((*cand2)->fn))
3256 *cand2 = (*cand2)->next;
3258 cand2 = &(*cand2)->next;
3260 /* ...if there are any non-deleted ones. */
3264 /* There may be duplicates in the set of candidates. We put off
3265 checking this condition as long as possible, since we have no way
3266 to eliminate duplicates from a set of functions in less than n^2
3267 time. Now we are about to emit an error message, so it is more
3268 permissible to go slowly. */
3269 for (cand1 = candidates; cand1; cand1 = cand1->next)
3271 tree fn = cand1->fn;
3272 /* Skip builtin candidates and conversion functions. */
3275 cand2 = &cand1->next;
3278 if (DECL_P ((*cand2)->fn)
3279 && equal_functions (fn, (*cand2)->fn))
3280 *cand2 = (*cand2)->next;
3282 cand2 = &(*cand2)->next;
3286 for (n_candidates = 0, cand1 = candidates; cand1; cand1 = cand1->next)
3289 inform_n (loc, n_candidates, "candidate is:", "candidates are:");
3290 for (; candidates; candidates = candidates->next)
3291 print_z_candidate (NULL, candidates);
3294 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3295 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3296 the result of the conversion function to convert it to the final
3297 desired type. Merge the two sequences into a single sequence,
3298 and return the merged sequence. */
3301 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
3304 bool bad = user_seq->bad_p;
3306 gcc_assert (user_seq->kind == ck_user);
3308 /* Find the end of the second conversion sequence. */
3309 for (t = &std_seq; (*t)->kind != ck_identity; t = &((*t)->u.next))
3311 /* The entire sequence is a user-conversion sequence. */
3312 (*t)->user_conv_p = true;
3317 /* Replace the identity conversion with the user conversion
3324 /* Handle overload resolution for initializing an object of class type from
3325 an initializer list. First we look for a suitable constructor that
3326 takes a std::initializer_list; if we don't find one, we then look for a
3327 non-list constructor.
3329 Parameters are as for add_candidates, except that the arguments are in
3330 the form of a CONSTRUCTOR (the initializer list) rather than a VEC, and
3331 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3334 add_list_candidates (tree fns, tree first_arg,
3335 tree init_list, tree totype,
3336 tree explicit_targs, bool template_only,
3337 tree conversion_path, tree access_path,
3339 struct z_candidate **candidates)
3343 gcc_assert (*candidates == NULL);
3345 /* We're looking for a ctor for list-initialization. */
3346 flags |= LOOKUP_LIST_INIT_CTOR;
3347 /* And we don't allow narrowing conversions. We also use this flag to
3348 avoid the copy constructor call for copy-list-initialization. */
3349 flags |= LOOKUP_NO_NARROWING;
3351 /* Always use the default constructor if the list is empty (DR 990). */
3352 if (CONSTRUCTOR_NELTS (init_list) == 0
3353 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
3355 /* If the class has a list ctor, try passing the list as a single
3356 argument first, but only consider list ctors. */
3357 else if (TYPE_HAS_LIST_CTOR (totype))
3359 flags |= LOOKUP_LIST_ONLY;
3360 args = make_tree_vector_single (init_list);
3361 add_candidates (fns, first_arg, args, NULL_TREE,
3362 explicit_targs, template_only, conversion_path,
3363 access_path, flags, candidates);
3364 if (any_strictly_viable (*candidates))
3368 args = ctor_to_vec (init_list);
3370 /* We aren't looking for list-ctors anymore. */
3371 flags &= ~LOOKUP_LIST_ONLY;
3372 /* We allow more user-defined conversions within an init-list. */
3373 flags &= ~LOOKUP_NO_CONVERSION;
3375 add_candidates (fns, first_arg, args, NULL_TREE,
3376 explicit_targs, template_only, conversion_path,
3377 access_path, flags, candidates);
3380 /* Returns the best overload candidate to perform the requested
3381 conversion. This function is used for three the overloading situations
3382 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3383 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3384 per [dcl.init.ref], so we ignore temporary bindings. */
3386 static struct z_candidate *
3387 build_user_type_conversion_1 (tree totype, tree expr, int flags)
3389 struct z_candidate *candidates, *cand;
3391 tree ctors = NULL_TREE;
3392 tree conv_fns = NULL_TREE;
3393 conversion *conv = NULL;
3394 tree first_arg = NULL_TREE;
3395 VEC(tree,gc) *args = NULL;
3402 fromtype = TREE_TYPE (expr);
3404 /* We represent conversion within a hierarchy using RVALUE_CONV and
3405 BASE_CONV, as specified by [over.best.ics]; these become plain
3406 constructor calls, as specified in [dcl.init]. */
3407 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
3408 || !DERIVED_FROM_P (totype, fromtype));
3410 if (MAYBE_CLASS_TYPE_P (totype))
3411 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3412 creating a garbage BASELINK; constructors can't be inherited. */
3413 ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
3415 if (MAYBE_CLASS_TYPE_P (fromtype))
3417 tree to_nonref = non_reference (totype);
3418 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
3419 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
3420 && DERIVED_FROM_P (to_nonref, fromtype)))
3422 /* [class.conv.fct] A conversion function is never used to
3423 convert a (possibly cv-qualified) object to the (possibly
3424 cv-qualified) same object type (or a reference to it), to a
3425 (possibly cv-qualified) base class of that type (or a
3426 reference to it)... */
3429 conv_fns = lookup_conversions (fromtype);
3433 flags |= LOOKUP_NO_CONVERSION;
3434 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3435 flags |= LOOKUP_NO_NARROWING;
3437 /* It's OK to bind a temporary for converting constructor arguments, but
3438 not in converting the return value of a conversion operator. */
3439 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
3440 flags &= ~LOOKUP_NO_TEMP_BIND;
3444 int ctorflags = flags;
3446 first_arg = build_int_cst (build_pointer_type (totype), 0);
3448 /* We should never try to call the abstract or base constructor
3450 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3451 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3453 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3455 /* List-initialization. */
3456 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3457 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3458 ctorflags, &candidates);
3462 args = make_tree_vector_single (expr);
3463 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3464 TYPE_BINFO (totype), TYPE_BINFO (totype),
3465 ctorflags, &candidates);
3468 for (cand = candidates; cand; cand = cand->next)
3470 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3472 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3473 set, then this is copy-initialization. In that case, "The
3474 result of the call is then used to direct-initialize the
3475 object that is the destination of the copy-initialization."
3478 We represent this in the conversion sequence with an
3479 rvalue conversion, which means a constructor call. */
3480 if (TREE_CODE (totype) != REFERENCE_TYPE
3481 && !(convflags & LOOKUP_NO_TEMP_BIND))
3483 = build_conv (ck_rvalue, totype, cand->second_conv);
3488 first_arg = build_this (expr);
3490 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3492 tree conversion_path = TREE_PURPOSE (conv_fns);
3493 struct z_candidate *old_candidates;
3495 /* If we are called to convert to a reference type, we are trying to
3496 find a direct binding, so don't even consider temporaries. If
3497 we don't find a direct binding, the caller will try again to
3498 look for a temporary binding. */
3499 if (TREE_CODE (totype) == REFERENCE_TYPE)
3500 convflags |= LOOKUP_NO_TEMP_BIND;
3502 old_candidates = candidates;
3503 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3505 conversion_path, TYPE_BINFO (fromtype),
3506 flags, &candidates);
3508 for (cand = candidates; cand != old_candidates; cand = cand->next)
3510 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3512 = implicit_conversion (totype,
3515 /*c_cast_p=*/false, convflags);
3517 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3518 copy-initialization. In that case, "The result of the
3519 call is then used to direct-initialize the object that is
3520 the destination of the copy-initialization." [dcl.init]
3522 We represent this in the conversion sequence with an
3523 rvalue conversion, which means a constructor call. But
3524 don't add a second rvalue conversion if there's already
3525 one there. Which there really shouldn't be, but it's
3526 harmless since we'd add it here anyway. */
3527 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3528 && !(convflags & LOOKUP_NO_TEMP_BIND))
3529 ics = build_conv (ck_rvalue, totype, ics);
3531 cand->second_conv = ics;
3536 cand->reason = arg_conversion_rejection (NULL_TREE, -1,
3539 else if (DECL_NONCONVERTING_P (cand->fn)
3540 && ics->rank > cr_exact)
3542 /* 13.3.1.5: For direct-initialization, those explicit
3543 conversion functions that are not hidden within S and
3544 yield type T or a type that can be converted to type T
3545 with a qualification conversion (4.4) are also candidate
3547 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3548 I've raised this issue with the committee. --jason 9/2011 */
3550 cand->reason = explicit_conversion_rejection (rettype, totype);
3552 else if (cand->viable == 1 && ics->bad_p)
3556 = bad_arg_conversion_rejection (NULL_TREE, -1,
3559 else if (primary_template_instantiation_p (cand->fn)
3560 && ics->rank > cr_exact)
3562 /* 13.3.3.1.2: If the user-defined conversion is specified by
3563 a specialization of a conversion function template, the
3564 second standard conversion sequence shall have exact match
3567 cand->reason = template_conversion_rejection (rettype, totype);
3572 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3576 release_tree_vector (args);
3580 cand = tourney (candidates);
3583 if (flags & LOOKUP_COMPLAIN)
3585 error ("conversion from %qT to %qT is ambiguous",
3587 print_z_candidates (location_of (expr), candidates);
3590 cand = candidates; /* any one will do */
3591 cand->second_conv = build_ambiguous_conv (totype, expr);
3592 cand->second_conv->user_conv_p = true;
3593 if (!any_strictly_viable (candidates))
3594 cand->second_conv->bad_p = true;
3595 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3596 ambiguous conversion is no worse than another user-defined
3602 /* Build the user conversion sequence. */
3605 (DECL_CONSTRUCTOR_P (cand->fn)
3606 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3607 build_identity_conv (TREE_TYPE (expr), expr));
3609 if (cand->viable == -1)
3612 /* Remember that this was a list-initialization. */
3613 if (flags & LOOKUP_NO_NARROWING)
3614 conv->check_narrowing = true;
3616 /* Combine it with the second conversion sequence. */
3617 cand->second_conv = merge_conversion_sequences (conv,
3623 /* Wrapper for above. */
3626 build_user_type_conversion (tree totype, tree expr, int flags)
3628 struct z_candidate *cand;
3631 bool subtime = timevar_cond_start (TV_OVERLOAD);
3632 cand = build_user_type_conversion_1 (totype, expr, flags);
3636 if (cand->second_conv->kind == ck_ambig)
3637 ret = error_mark_node;
3640 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3641 ret = convert_from_reference (expr);
3647 timevar_cond_stop (TV_OVERLOAD, subtime);
3651 /* Subroutine of convert_nontype_argument.
3653 EXPR is an argument for a template non-type parameter of integral or
3654 enumeration type. Do any necessary conversions (that are permitted for
3655 non-type arguments) to convert it to the parameter type.
3657 If conversion is successful, returns the converted expression;
3658 otherwise, returns error_mark_node. */
3661 build_integral_nontype_arg_conv (tree type, tree expr, tsubst_flags_t complain)
3667 if (error_operand_p (expr))
3668 return error_mark_node;
3670 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
3672 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3673 p = conversion_obstack_alloc (0);
3675 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
3679 /* for a non-type template-parameter of integral or
3680 enumeration type, integral promotions (4.5) and integral
3681 conversions (4.7) are applied. */
3682 /* It should be sufficient to check the outermost conversion step, since
3683 there are no qualification conversions to integer type. */
3687 /* A conversion function is OK. If it isn't constexpr, we'll
3688 complain later that the argument isn't constant. */
3690 /* The lvalue-to-rvalue conversion is OK. */
3696 t = conv->u.next->type;
3697 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t))
3700 if (complain & tf_error)
3701 error ("conversion from %qT to %qT not considered for "
3702 "non-type template argument", t, type);
3703 /* and fall through. */
3711 expr = convert_like (conv, expr, complain);
3713 expr = error_mark_node;
3715 /* Free all the conversions we allocated. */
3716 obstack_free (&conversion_obstack, p);
3721 /* Do any initial processing on the arguments to a function call. */
3723 static VEC(tree,gc) *
3724 resolve_args (VEC(tree,gc) *args, tsubst_flags_t complain)
3729 FOR_EACH_VEC_ELT (tree, args, ix, arg)
3731 if (error_operand_p (arg))
3733 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3735 if (complain & tf_error)
3736 error ("invalid use of void expression");
3739 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3745 /* Perform overload resolution on FN, which is called with the ARGS.
3747 Return the candidate function selected by overload resolution, or
3748 NULL if the event that overload resolution failed. In the case
3749 that overload resolution fails, *CANDIDATES will be the set of
3750 candidates considered, and ANY_VIABLE_P will be set to true or
3751 false to indicate whether or not any of the candidates were
3754 The ARGS should already have gone through RESOLVE_ARGS before this
3755 function is called. */
3757 static struct z_candidate *
3758 perform_overload_resolution (tree fn,
3759 const VEC(tree,gc) *args,
3760 struct z_candidate **candidates,
3763 struct z_candidate *cand;
3764 tree explicit_targs;
3767 bool subtime = timevar_cond_start (TV_OVERLOAD);
3769 explicit_targs = NULL_TREE;
3773 *any_viable_p = true;
3776 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3777 || TREE_CODE (fn) == TEMPLATE_DECL
3778 || TREE_CODE (fn) == OVERLOAD
3779 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3781 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3783 explicit_targs = TREE_OPERAND (fn, 1);
3784 fn = TREE_OPERAND (fn, 0);
3788 /* Add the various candidate functions. */
3789 add_candidates (fn, NULL_TREE, args, NULL_TREE,
3790 explicit_targs, template_only,
3791 /*conversion_path=*/NULL_TREE,
3792 /*access_path=*/NULL_TREE,
3796 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3798 cand = tourney (*candidates);
3802 timevar_cond_stop (TV_OVERLOAD, subtime);
3806 /* Print an error message about being unable to build a call to FN with
3807 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
3808 be located; CANDIDATES is a possibly empty list of such
3812 print_error_for_call_failure (tree fn, VEC(tree,gc) *args, bool any_viable_p,
3813 struct z_candidate *candidates)
3815 tree name = DECL_NAME (OVL_CURRENT (fn));
3816 location_t loc = location_of (name);
3819 error_at (loc, "no matching function for call to %<%D(%A)%>",
3820 name, build_tree_list_vec (args));
3822 error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous",
3823 name, build_tree_list_vec (args));
3825 print_z_candidates (loc, candidates);
3828 /* Return an expression for a call to FN (a namespace-scope function,
3829 or a static member function) with the ARGS. This may change
3833 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3834 tsubst_flags_t complain)
3836 struct z_candidate *candidates, *cand;
3841 if (args != NULL && *args != NULL)
3843 *args = resolve_args (*args, complain);
3845 return error_mark_node;
3849 tm_malloc_replacement (fn);
3851 /* If this function was found without using argument dependent
3852 lookup, then we want to ignore any undeclared friend
3858 fn = remove_hidden_names (fn);
3861 if (complain & tf_error)
3862 print_error_for_call_failure (orig_fn, *args, false, NULL);
3863 return error_mark_node;
3867 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3868 p = conversion_obstack_alloc (0);
3870 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3874 if (complain & tf_error)
3876 if (!any_viable_p && candidates && ! candidates->next
3877 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
3878 return cp_build_function_call_vec (candidates->fn, args, complain);
3879 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3880 fn = TREE_OPERAND (fn, 0);
3881 print_error_for_call_failure (fn, *args, any_viable_p, candidates);
3883 result = error_mark_node;
3887 int flags = LOOKUP_NORMAL;
3888 /* If fn is template_id_expr, the call has explicit template arguments
3889 (e.g. func<int>(5)), communicate this info to build_over_call
3890 through flags so that later we can use it to decide whether to warn
3891 about peculiar null pointer conversion. */
3892 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3893 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
3894 result = build_over_call (cand, flags, complain);
3897 /* Free all the conversions we allocated. */
3898 obstack_free (&conversion_obstack, p);
3903 /* Build a call to a global operator new. FNNAME is the name of the
3904 operator (either "operator new" or "operator new[]") and ARGS are
3905 the arguments provided. This may change ARGS. *SIZE points to the
3906 total number of bytes required by the allocation, and is updated if
3907 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3908 be used. If this function determines that no cookie should be
3909 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3910 non-NULL, it will be set, upon return, to the allocation function
3914 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3915 tree *size, tree *cookie_size,
3919 struct z_candidate *candidates;
3920 struct z_candidate *cand;
3925 VEC_safe_insert (tree, gc, *args, 0, *size);
3926 *args = resolve_args (*args, tf_warning_or_error);
3928 return error_mark_node;
3934 If this lookup fails to find the name, or if the allocated type
3935 is not a class type, the allocation function's name is looked
3936 up in the global scope.
3938 we disregard block-scope declarations of "operator new". */
3939 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3941 /* Figure out what function is being called. */
3942 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3944 /* If no suitable function could be found, issue an error message
3948 print_error_for_call_failure (fns, *args, any_viable_p, candidates);
3949 return error_mark_node;
3952 /* If a cookie is required, add some extra space. Whether
3953 or not a cookie is required cannot be determined until
3954 after we know which function was called. */
3957 bool use_cookie = true;
3958 if (!abi_version_at_least (2))
3960 /* In G++ 3.2, the check was implemented incorrectly; it
3961 looked at the placement expression, rather than the
3962 type of the function. */
3963 if (VEC_length (tree, *args) == 2
3964 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3972 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3973 /* Skip the size_t parameter. */
3974 arg_types = TREE_CHAIN (arg_types);
3975 /* Check the remaining parameters (if any). */
3977 && TREE_CHAIN (arg_types) == void_list_node
3978 && same_type_p (TREE_VALUE (arg_types),
3982 /* If we need a cookie, adjust the number of bytes allocated. */
3985 /* Update the total size. */
3986 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3987 /* Update the argument list to reflect the adjusted size. */
3988 VEC_replace (tree, *args, 0, *size);
3991 *cookie_size = NULL_TREE;
3994 /* Tell our caller which function we decided to call. */
3998 /* Build the CALL_EXPR. */
3999 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
4002 /* Build a new call to operator(). This may change ARGS. */
4005 build_op_call_1 (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
4007 struct z_candidate *candidates = 0, *cand;
4008 tree fns, convs, first_mem_arg = NULL_TREE;
4009 tree type = TREE_TYPE (obj);
4011 tree result = NULL_TREE;
4014 if (error_operand_p (obj))
4015 return error_mark_node;
4017 obj = prep_operand (obj);
4019 if (TYPE_PTRMEMFUNC_P (type))
4021 if (complain & tf_error)
4022 /* It's no good looking for an overloaded operator() on a
4023 pointer-to-member-function. */
4024 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
4025 return error_mark_node;
4028 if (TYPE_BINFO (type))
4030 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
4031 if (fns == error_mark_node)
4032 return error_mark_node;
4037 if (args != NULL && *args != NULL)
4039 *args = resolve_args (*args, complain);
4041 return error_mark_node;
4044 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4045 p = conversion_obstack_alloc (0);
4049 first_mem_arg = build_this (obj);
4051 add_candidates (BASELINK_FUNCTIONS (fns),
4052 first_mem_arg, *args, NULL_TREE,
4054 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
4055 LOOKUP_NORMAL, &candidates);
4058 convs = lookup_conversions (type);
4060 for (; convs; convs = TREE_CHAIN (convs))
4062 tree fns = TREE_VALUE (convs);
4063 tree totype = TREE_TYPE (convs);
4065 if ((TREE_CODE (totype) == POINTER_TYPE
4066 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
4067 || (TREE_CODE (totype) == REFERENCE_TYPE
4068 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
4069 || (TREE_CODE (totype) == REFERENCE_TYPE
4070 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
4071 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
4072 for (; fns; fns = OVL_NEXT (fns))
4074 tree fn = OVL_CURRENT (fns);
4076 if (DECL_NONCONVERTING_P (fn))
4079 if (TREE_CODE (fn) == TEMPLATE_DECL)
4080 add_template_conv_candidate
4081 (&candidates, fn, obj, NULL_TREE, *args, totype,
4082 /*access_path=*/NULL_TREE,
4083 /*conversion_path=*/NULL_TREE);
4085 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
4086 *args, /*conversion_path=*/NULL_TREE,
4087 /*access_path=*/NULL_TREE);
4091 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4094 if (complain & tf_error)
4096 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
4097 build_tree_list_vec (*args));
4098 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4100 result = error_mark_node;
4104 cand = tourney (candidates);
4107 if (complain & tf_error)
4109 error ("call of %<(%T) (%A)%> is ambiguous",
4110 TREE_TYPE (obj), build_tree_list_vec (*args));
4111 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4113 result = error_mark_node;
4115 /* Since cand->fn will be a type, not a function, for a conversion
4116 function, we must be careful not to unconditionally look at
4118 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
4119 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
4120 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4123 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
4125 obj = convert_from_reference (obj);
4126 result = cp_build_function_call_vec (obj, args, complain);
4130 /* Free all the conversions we allocated. */
4131 obstack_free (&conversion_obstack, p);
4136 /* Wrapper for above. */
4139 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
4142 bool subtime = timevar_cond_start (TV_OVERLOAD);
4143 ret = build_op_call_1 (obj, args, complain);
4144 timevar_cond_stop (TV_OVERLOAD, subtime);
4149 op_error (enum tree_code code, enum tree_code code2,
4150 tree arg1, tree arg2, tree arg3, bool match)
4154 if (code == MODIFY_EXPR)
4155 opname = assignment_operator_name_info[code2].name;
4157 opname = operator_name_info[code].name;
4163 error ("ambiguous overload for ternary %<operator?:%> "
4164 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4166 error ("no match for ternary %<operator?:%> "
4167 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4170 case POSTINCREMENT_EXPR:
4171 case POSTDECREMENT_EXPR:
4173 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
4174 opname, arg1, opname);
4176 error ("no match for %<operator%s%> in %<%E%s%>",
4177 opname, arg1, opname);
4182 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
4185 error ("no match for %<operator[]%> in %<%E[%E]%>",
4192 error ("ambiguous overload for %qs in %<%s %E%>",
4193 opname, opname, arg1);
4195 error ("no match for %qs in %<%s %E%>",
4196 opname, opname, arg1);
4202 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
4203 opname, arg1, opname, arg2);
4205 error ("no match for %<operator%s%> in %<%E %s %E%>",
4206 opname, arg1, opname, arg2);
4209 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
4210 opname, opname, arg1);
4212 error ("no match for %<operator%s%> in %<%s%E%>",
4213 opname, opname, arg1);
4218 /* Return the implicit conversion sequence that could be used to
4219 convert E1 to E2 in [expr.cond]. */
4222 conditional_conversion (tree e1, tree e2)
4224 tree t1 = non_reference (TREE_TYPE (e1));
4225 tree t2 = non_reference (TREE_TYPE (e2));
4231 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4232 implicitly converted (clause _conv_) to the type "lvalue reference to
4233 T2", subject to the constraint that in the conversion the
4234 reference must bind directly (_dcl.init.ref_) to an lvalue. */
4235 if (real_lvalue_p (e2))
4237 conv = implicit_conversion (build_reference_type (t2),
4241 LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND
4242 |LOOKUP_ONLYCONVERTING);
4249 If E1 and E2 have class type, and the underlying class types are
4250 the same or one is a base class of the other: E1 can be converted
4251 to match E2 if the class of T2 is the same type as, or a base
4252 class of, the class of T1, and the cv-qualification of T2 is the
4253 same cv-qualification as, or a greater cv-qualification than, the
4254 cv-qualification of T1. If the conversion is applied, E1 is
4255 changed to an rvalue of type T2 that still refers to the original
4256 source class object (or the appropriate subobject thereof). */
4257 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
4258 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
4260 if (good_base && at_least_as_qualified_p (t2, t1))
4262 conv = build_identity_conv (t1, e1);
4263 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
4264 TYPE_MAIN_VARIANT (t2)))
4265 conv = build_conv (ck_base, t2, conv);
4267 conv = build_conv (ck_rvalue, t2, conv);
4276 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4277 converted to the type that expression E2 would have if E2 were
4278 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4279 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
4283 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4284 arguments to the conditional expression. */
4287 build_conditional_expr_1 (tree arg1, tree arg2, tree arg3,
4288 tsubst_flags_t complain)
4292 tree result = NULL_TREE;
4293 tree result_type = NULL_TREE;
4294 bool lvalue_p = true;
4295 struct z_candidate *candidates = 0;
4296 struct z_candidate *cand;
4299 /* As a G++ extension, the second argument to the conditional can be
4300 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4301 c'.) If the second operand is omitted, make sure it is
4302 calculated only once. */
4305 if (complain & tf_error)
4306 pedwarn (input_location, OPT_pedantic,
4307 "ISO C++ forbids omitting the middle term of a ?: expression");
4309 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4310 if (real_lvalue_p (arg1))
4311 arg2 = arg1 = stabilize_reference (arg1);
4313 arg2 = arg1 = save_expr (arg1);
4318 The first expression is implicitly converted to bool (clause
4320 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
4323 /* If something has already gone wrong, just pass that fact up the
4325 if (error_operand_p (arg1)
4326 || error_operand_p (arg2)
4327 || error_operand_p (arg3))
4328 return error_mark_node;
4332 If either the second or the third operand has type (possibly
4333 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4334 array-to-pointer (_conv.array_), and function-to-pointer
4335 (_conv.func_) standard conversions are performed on the second
4336 and third operands. */
4337 arg2_type = unlowered_expr_type (arg2);
4338 arg3_type = unlowered_expr_type (arg3);
4339 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
4341 /* Do the conversions. We don't these for `void' type arguments
4342 since it can't have any effect and since decay_conversion
4343 does not handle that case gracefully. */
4344 if (!VOID_TYPE_P (arg2_type))
4345 arg2 = decay_conversion (arg2);
4346 if (!VOID_TYPE_P (arg3_type))
4347 arg3 = decay_conversion (arg3);
4348 arg2_type = TREE_TYPE (arg2);
4349 arg3_type = TREE_TYPE (arg3);
4353 One of the following shall hold:
4355 --The second or the third operand (but not both) is a
4356 throw-expression (_except.throw_); the result is of the
4357 type of the other and is an rvalue.
4359 --Both the second and the third operands have type void; the
4360 result is of type void and is an rvalue.
4362 We must avoid calling force_rvalue for expressions of type
4363 "void" because it will complain that their value is being
4365 if (TREE_CODE (arg2) == THROW_EXPR
4366 && TREE_CODE (arg3) != THROW_EXPR)
4368 if (!VOID_TYPE_P (arg3_type))
4370 arg3 = force_rvalue (arg3, complain);
4371 if (arg3 == error_mark_node)
4372 return error_mark_node;
4374 arg3_type = TREE_TYPE (arg3);
4375 result_type = arg3_type;
4377 else if (TREE_CODE (arg2) != THROW_EXPR
4378 && TREE_CODE (arg3) == THROW_EXPR)
4380 if (!VOID_TYPE_P (arg2_type))
4382 arg2 = force_rvalue (arg2, complain);
4383 if (arg2 == error_mark_node)
4384 return error_mark_node;
4386 arg2_type = TREE_TYPE (arg2);
4387 result_type = arg2_type;
4389 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
4390 result_type = void_type_node;
4393 if (complain & tf_error)
4395 if (VOID_TYPE_P (arg2_type))
4396 error ("second operand to the conditional operator "
4397 "is of type %<void%>, "
4398 "but the third operand is neither a throw-expression "
4399 "nor of type %<void%>");
4401 error ("third operand to the conditional operator "
4402 "is of type %<void%>, "
4403 "but the second operand is neither a throw-expression "
4404 "nor of type %<void%>");
4406 return error_mark_node;
4410 goto valid_operands;
4414 Otherwise, if the second and third operand have different types,
4415 and either has (possibly cv-qualified) class type, an attempt is
4416 made to convert each of those operands to the type of the other. */
4417 else if (!same_type_p (arg2_type, arg3_type)
4418 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4423 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4424 p = conversion_obstack_alloc (0);
4426 conv2 = conditional_conversion (arg2, arg3);
4427 conv3 = conditional_conversion (arg3, arg2);
4431 If both can be converted, or one can be converted but the
4432 conversion is ambiguous, the program is ill-formed. If
4433 neither can be converted, the operands are left unchanged and
4434 further checking is performed as described below. If exactly
4435 one conversion is possible, that conversion is applied to the
4436 chosen operand and the converted operand is used in place of
4437 the original operand for the remainder of this section. */
4438 if ((conv2 && !conv2->bad_p
4439 && conv3 && !conv3->bad_p)
4440 || (conv2 && conv2->kind == ck_ambig)
4441 || (conv3 && conv3->kind == ck_ambig))
4443 error ("operands to ?: have different types %qT and %qT",
4444 arg2_type, arg3_type);
4445 result = error_mark_node;
4447 else if (conv2 && (!conv2->bad_p || !conv3))
4449 arg2 = convert_like (conv2, arg2, complain);
4450 arg2 = convert_from_reference (arg2);
4451 arg2_type = TREE_TYPE (arg2);
4452 /* Even if CONV2 is a valid conversion, the result of the
4453 conversion may be invalid. For example, if ARG3 has type
4454 "volatile X", and X does not have a copy constructor
4455 accepting a "volatile X&", then even if ARG2 can be
4456 converted to X, the conversion will fail. */
4457 if (error_operand_p (arg2))
4458 result = error_mark_node;
4460 else if (conv3 && (!conv3->bad_p || !conv2))
4462 arg3 = convert_like (conv3, arg3, complain);
4463 arg3 = convert_from_reference (arg3);
4464 arg3_type = TREE_TYPE (arg3);
4465 if (error_operand_p (arg3))
4466 result = error_mark_node;
4469 /* Free all the conversions we allocated. */
4470 obstack_free (&conversion_obstack, p);
4475 /* If, after the conversion, both operands have class type,
4476 treat the cv-qualification of both operands as if it were the
4477 union of the cv-qualification of the operands.
4479 The standard is not clear about what to do in this
4480 circumstance. For example, if the first operand has type
4481 "const X" and the second operand has a user-defined
4482 conversion to "volatile X", what is the type of the second
4483 operand after this step? Making it be "const X" (matching
4484 the first operand) seems wrong, as that discards the
4485 qualification without actually performing a copy. Leaving it
4486 as "volatile X" seems wrong as that will result in the
4487 conditional expression failing altogether, even though,
4488 according to this step, the one operand could be converted to
4489 the type of the other. */
4490 if ((conv2 || conv3)
4491 && CLASS_TYPE_P (arg2_type)
4492 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
4493 arg2_type = arg3_type =
4494 cp_build_qualified_type (arg2_type,
4495 cp_type_quals (arg2_type)
4496 | cp_type_quals (arg3_type));
4501 If the second and third operands are lvalues and have the same
4502 type, the result is of that type and is an lvalue. */
4503 if (real_lvalue_p (arg2)
4504 && real_lvalue_p (arg3)
4505 && same_type_p (arg2_type, arg3_type))
4507 result_type = arg2_type;
4508 arg2 = mark_lvalue_use (arg2);
4509 arg3 = mark_lvalue_use (arg3);
4510 goto valid_operands;
4515 Otherwise, the result is an rvalue. If the second and third
4516 operand do not have the same type, and either has (possibly
4517 cv-qualified) class type, overload resolution is used to
4518 determine the conversions (if any) to be applied to the operands
4519 (_over.match.oper_, _over.built_). */
4521 if (!same_type_p (arg2_type, arg3_type)
4522 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4528 /* Rearrange the arguments so that add_builtin_candidate only has
4529 to know about two args. In build_builtin_candidate, the
4530 arguments are unscrambled. */
4534 add_builtin_candidates (&candidates,
4537 ansi_opname (COND_EXPR),
4543 If the overload resolution fails, the program is
4545 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4548 if (complain & tf_error)
4550 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4551 print_z_candidates (location_of (arg1), candidates);
4553 return error_mark_node;
4555 cand = tourney (candidates);
4558 if (complain & tf_error)
4560 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4561 print_z_candidates (location_of (arg1), candidates);
4563 return error_mark_node;
4568 Otherwise, the conversions thus determined are applied, and
4569 the converted operands are used in place of the original
4570 operands for the remainder of this section. */
4571 conv = cand->convs[0];
4572 arg1 = convert_like (conv, arg1, complain);
4573 conv = cand->convs[1];
4574 arg2 = convert_like (conv, arg2, complain);
4575 arg2_type = TREE_TYPE (arg2);
4576 conv = cand->convs[2];
4577 arg3 = convert_like (conv, arg3, complain);
4578 arg3_type = TREE_TYPE (arg3);
4583 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
4584 and function-to-pointer (_conv.func_) standard conversions are
4585 performed on the second and third operands.
4587 We need to force the lvalue-to-rvalue conversion here for class types,
4588 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
4589 that isn't wrapped with a TARGET_EXPR plays havoc with exception
4592 arg2 = force_rvalue (arg2, complain);
4593 if (!CLASS_TYPE_P (arg2_type))
4594 arg2_type = TREE_TYPE (arg2);
4596 arg3 = force_rvalue (arg3, complain);
4597 if (!CLASS_TYPE_P (arg3_type))
4598 arg3_type = TREE_TYPE (arg3);
4600 if (arg2 == error_mark_node || arg3 == error_mark_node)
4601 return error_mark_node;
4605 After those conversions, one of the following shall hold:
4607 --The second and third operands have the same type; the result is of
4609 if (same_type_p (arg2_type, arg3_type))
4610 result_type = arg2_type;
4613 --The second and third operands have arithmetic or enumeration
4614 type; the usual arithmetic conversions are performed to bring
4615 them to a common type, and the result is of that type. */
4616 else if ((ARITHMETIC_TYPE_P (arg2_type)
4617 || UNSCOPED_ENUM_P (arg2_type))
4618 && (ARITHMETIC_TYPE_P (arg3_type)
4619 || UNSCOPED_ENUM_P (arg3_type)))
4621 /* In this case, there is always a common type. */
4622 result_type = type_after_usual_arithmetic_conversions (arg2_type,
4624 do_warn_double_promotion (result_type, arg2_type, arg3_type,
4625 "implicit conversion from %qT to %qT to "
4626 "match other result of conditional",
4629 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
4630 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
4632 if (complain & tf_warning)
4634 "enumeral mismatch in conditional expression: %qT vs %qT",
4635 arg2_type, arg3_type);
4637 else if (extra_warnings
4638 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
4639 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
4640 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
4641 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
4643 if (complain & tf_warning)
4645 "enumeral and non-enumeral type in conditional expression");
4648 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4649 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4653 --The second and third operands have pointer type, or one has
4654 pointer type and the other is a null pointer constant; pointer
4655 conversions (_conv.ptr_) and qualification conversions
4656 (_conv.qual_) are performed to bring them to their composite
4657 pointer type (_expr.rel_). The result is of the composite
4660 --The second and third operands have pointer to member type, or
4661 one has pointer to member type and the other is a null pointer
4662 constant; pointer to member conversions (_conv.mem_) and
4663 qualification conversions (_conv.qual_) are performed to bring
4664 them to a common type, whose cv-qualification shall match the
4665 cv-qualification of either the second or the third operand.
4666 The result is of the common type. */
4667 else if ((null_ptr_cst_p (arg2)
4668 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
4669 || (null_ptr_cst_p (arg3)
4670 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
4671 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
4672 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
4673 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
4675 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
4676 arg3, CPO_CONDITIONAL_EXPR,
4678 if (result_type == error_mark_node)
4679 return error_mark_node;
4680 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4681 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4686 if (complain & tf_error)
4687 error ("operands to ?: have different types %qT and %qT",
4688 arg2_type, arg3_type);
4689 return error_mark_node;
4693 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4694 if (!cp_unevaluated_operand)
4695 /* Avoid folding within decltype (c++/42013) and noexcept. */
4696 result = fold_if_not_in_template (result);
4698 /* We can't use result_type below, as fold might have returned a
4703 /* Expand both sides into the same slot, hopefully the target of
4704 the ?: expression. We used to check for TARGET_EXPRs here,
4705 but now we sometimes wrap them in NOP_EXPRs so the test would
4707 if (CLASS_TYPE_P (TREE_TYPE (result)))
4708 result = get_target_expr (result);
4709 /* If this expression is an rvalue, but might be mistaken for an
4710 lvalue, we must add a NON_LVALUE_EXPR. */
4711 result = rvalue (result);
4717 /* Wrapper for above. */
4720 build_conditional_expr (tree arg1, tree arg2, tree arg3,
4721 tsubst_flags_t complain)
4724 bool subtime = timevar_cond_start (TV_OVERLOAD);
4725 ret = build_conditional_expr_1 (arg1, arg2, arg3, complain);
4726 timevar_cond_stop (TV_OVERLOAD, subtime);
4730 /* OPERAND is an operand to an expression. Perform necessary steps
4731 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4735 prep_operand (tree operand)
4739 if (CLASS_TYPE_P (TREE_TYPE (operand))
4740 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4741 /* Make sure the template type is instantiated now. */
4742 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4748 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4749 OVERLOAD) to the CANDIDATES, returning an updated list of
4750 CANDIDATES. The ARGS are the arguments provided to the call;
4751 if FIRST_ARG is non-null it is the implicit object argument,
4752 otherwise the first element of ARGS is used if needed. The
4753 EXPLICIT_TARGS are explicit template arguments provided.
4754 TEMPLATE_ONLY is true if only template functions should be
4755 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4756 add_function_candidate. */
4759 add_candidates (tree fns, tree first_arg, const VEC(tree,gc) *args,
4761 tree explicit_targs, bool template_only,
4762 tree conversion_path, tree access_path,
4764 struct z_candidate **candidates)
4767 const VEC(tree,gc) *non_static_args;
4768 bool check_list_ctor;
4769 bool check_converting;
4770 unification_kind_t strict;
4776 /* Precalculate special handling of constructors and conversion ops. */
4777 fn = OVL_CURRENT (fns);
4778 if (DECL_CONV_FN_P (fn))
4780 check_list_ctor = false;
4781 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4782 if (flags & LOOKUP_NO_CONVERSION)
4783 /* We're doing return_type(x). */
4784 strict = DEDUCE_CONV;
4786 /* We're doing x.operator return_type(). */
4787 strict = DEDUCE_EXACT;
4788 /* [over.match.funcs] For conversion functions, the function
4789 is considered to be a member of the class of the implicit
4790 object argument for the purpose of defining the type of
4791 the implicit object parameter. */
4792 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (first_arg)));
4796 if (DECL_CONSTRUCTOR_P (fn))
4798 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
4799 /* For list-initialization we consider explicit constructors
4800 and complain if one is chosen. */
4802 = ((flags & (LOOKUP_ONLYCONVERTING|LOOKUP_LIST_INIT_CTOR))
4803 == LOOKUP_ONLYCONVERTING);
4807 check_list_ctor = false;
4808 check_converting = false;
4810 strict = DEDUCE_CALL;
4811 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4815 non_static_args = args;
4817 /* Delay creating the implicit this parameter until it is needed. */
4818 non_static_args = NULL;
4820 for (; fns; fns = OVL_NEXT (fns))
4823 const VEC(tree,gc) *fn_args;
4825 fn = OVL_CURRENT (fns);
4827 if (check_converting && DECL_NONCONVERTING_P (fn))
4829 if (check_list_ctor && !is_list_ctor (fn))
4832 /* Figure out which set of arguments to use. */
4833 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4835 /* If this function is a non-static member and we didn't get an
4836 implicit object argument, move it out of args. */
4837 if (first_arg == NULL_TREE)
4841 VEC(tree,gc) *tempvec
4842 = VEC_alloc (tree, gc, VEC_length (tree, args) - 1);
4843 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4844 VEC_quick_push (tree, tempvec, arg);
4845 non_static_args = tempvec;
4846 first_arg = build_this (VEC_index (tree, args, 0));
4849 fn_first_arg = first_arg;
4850 fn_args = non_static_args;
4854 /* Otherwise, just use the list of arguments provided. */
4855 fn_first_arg = NULL_TREE;
4859 if (TREE_CODE (fn) == TEMPLATE_DECL)
4860 add_template_candidate (candidates,
4871 else if (!template_only)
4872 add_function_candidate (candidates,
4883 /* Even unsigned enum types promote to signed int. We don't want to
4884 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4885 original argument and ARG is the argument after any conversions
4886 have been applied. We set TREE_NO_WARNING if we have added a cast
4887 from an unsigned enum type to a signed integer type. */
4890 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4892 if (orig_arg != NULL_TREE
4895 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4896 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4897 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4898 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4899 TREE_NO_WARNING (arg) = 1;
4903 build_new_op_1 (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4904 tree *overload, tsubst_flags_t complain)
4906 tree orig_arg1 = arg1;
4907 tree orig_arg2 = arg2;
4908 tree orig_arg3 = arg3;
4909 struct z_candidate *candidates = 0, *cand;
4910 VEC(tree,gc) *arglist;
4913 tree result = NULL_TREE;
4914 bool result_valid_p = false;
4915 enum tree_code code2 = NOP_EXPR;
4916 enum tree_code code_orig_arg1 = ERROR_MARK;
4917 enum tree_code code_orig_arg2 = ERROR_MARK;
4923 if (error_operand_p (arg1)
4924 || error_operand_p (arg2)
4925 || error_operand_p (arg3))
4926 return error_mark_node;
4928 if (code == MODIFY_EXPR)
4930 code2 = TREE_CODE (arg3);
4932 fnname = ansi_assopname (code2);
4935 fnname = ansi_opname (code);
4937 arg1 = prep_operand (arg1);
4943 case VEC_DELETE_EXPR:
4945 /* Use build_op_new_call and build_op_delete_call instead. */
4949 /* Use build_op_call instead. */
4952 case TRUTH_ORIF_EXPR:
4953 case TRUTH_ANDIF_EXPR:
4954 case TRUTH_AND_EXPR:
4956 /* These are saved for the sake of warn_logical_operator. */
4957 code_orig_arg1 = TREE_CODE (arg1);
4958 code_orig_arg2 = TREE_CODE (arg2);
4964 arg2 = prep_operand (arg2);
4965 arg3 = prep_operand (arg3);
4967 if (code == COND_EXPR)
4968 /* Use build_conditional_expr instead. */
4970 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4971 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4974 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4975 arg2 = integer_zero_node;
4977 arglist = VEC_alloc (tree, gc, 3);
4978 VEC_quick_push (tree, arglist, arg1);
4979 if (arg2 != NULL_TREE)
4980 VEC_quick_push (tree, arglist, arg2);
4981 if (arg3 != NULL_TREE)
4982 VEC_quick_push (tree, arglist, arg3);
4984 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4985 p = conversion_obstack_alloc (0);
4987 /* Add namespace-scope operators to the list of functions to
4989 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4990 NULL_TREE, arglist, NULL_TREE,
4991 NULL_TREE, false, NULL_TREE, NULL_TREE,
4992 flags, &candidates);
4993 /* Add class-member operators to the candidate set. */
4994 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4998 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4999 if (fns == error_mark_node)
5001 result = error_mark_node;
5002 goto user_defined_result_ready;
5005 add_candidates (BASELINK_FUNCTIONS (fns),
5006 NULL_TREE, arglist, NULL_TREE,
5008 BASELINK_BINFO (fns),
5009 BASELINK_ACCESS_BINFO (fns),
5010 flags, &candidates);
5015 args[2] = NULL_TREE;
5017 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
5023 /* For these, the built-in candidates set is empty
5024 [over.match.oper]/3. We don't want non-strict matches
5025 because exact matches are always possible with built-in
5026 operators. The built-in candidate set for COMPONENT_REF
5027 would be empty too, but since there are no such built-in
5028 operators, we accept non-strict matches for them. */
5033 strict_p = pedantic;
5037 candidates = splice_viable (candidates, strict_p, &any_viable_p);
5042 case POSTINCREMENT_EXPR:
5043 case POSTDECREMENT_EXPR:
5044 /* Don't try anything fancy if we're not allowed to produce
5046 if (!(complain & tf_error))
5047 return error_mark_node;
5049 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5050 distinguish between prefix and postfix ++ and
5051 operator++() was used for both, so we allow this with
5053 if (flags & LOOKUP_COMPLAIN)
5055 const char *msg = (flag_permissive)
5056 ? G_("no %<%D(int)%> declared for postfix %qs,"
5057 " trying prefix operator instead")
5058 : G_("no %<%D(int)%> declared for postfix %qs");
5059 permerror (input_location, msg, fnname,
5060 operator_name_info[code].name);
5063 if (!flag_permissive)
5064 return error_mark_node;
5066 if (code == POSTINCREMENT_EXPR)
5067 code = PREINCREMENT_EXPR;
5069 code = PREDECREMENT_EXPR;
5070 result = build_new_op_1 (code, flags, arg1, NULL_TREE, NULL_TREE,
5071 overload, complain);
5074 /* The caller will deal with these. */
5079 result_valid_p = true;
5083 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5085 /* If one of the arguments of the operator represents
5086 an invalid use of member function pointer, try to report
5087 a meaningful error ... */
5088 if (invalid_nonstatic_memfn_p (arg1, tf_error)
5089 || invalid_nonstatic_memfn_p (arg2, tf_error)
5090 || invalid_nonstatic_memfn_p (arg3, tf_error))
5091 /* We displayed the error message. */;
5094 /* ... Otherwise, report the more generic
5095 "no matching operator found" error */
5096 op_error (code, code2, arg1, arg2, arg3, FALSE);
5097 print_z_candidates (input_location, candidates);
5100 result = error_mark_node;
5106 cand = tourney (candidates);
5109 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5111 op_error (code, code2, arg1, arg2, arg3, TRUE);
5112 print_z_candidates (input_location, candidates);
5114 result = error_mark_node;
5116 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
5119 *overload = cand->fn;
5121 if (resolve_args (arglist, complain) == NULL)
5122 result = error_mark_node;
5124 result = build_over_call (cand, LOOKUP_NORMAL, complain);
5128 /* Give any warnings we noticed during overload resolution. */
5129 if (cand->warnings && (complain & tf_warning))
5131 struct candidate_warning *w;
5132 for (w = cand->warnings; w; w = w->next)
5133 joust (cand, w->loser, 1);
5136 /* Check for comparison of different enum types. */
5145 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
5146 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
5147 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
5148 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
5149 && (complain & tf_warning))
5151 warning (OPT_Wenum_compare,
5152 "comparison between %q#T and %q#T",
5153 TREE_TYPE (arg1), TREE_TYPE (arg2));
5160 /* We need to strip any leading REF_BIND so that bitfields
5161 don't cause errors. This should not remove any important
5162 conversions, because builtins don't apply to class
5163 objects directly. */
5164 conv = cand->convs[0];
5165 if (conv->kind == ck_ref_bind)
5166 conv = conv->u.next;
5167 arg1 = convert_like (conv, arg1, complain);
5171 /* We need to call warn_logical_operator before
5172 converting arg2 to a boolean_type. */
5173 if (complain & tf_warning)
5174 warn_logical_operator (input_location, code, boolean_type_node,
5175 code_orig_arg1, arg1,
5176 code_orig_arg2, arg2);
5178 conv = cand->convs[1];
5179 if (conv->kind == ck_ref_bind)
5180 conv = conv->u.next;
5181 arg2 = convert_like (conv, arg2, complain);
5185 conv = cand->convs[2];
5186 if (conv->kind == ck_ref_bind)
5187 conv = conv->u.next;
5188 arg3 = convert_like (conv, arg3, complain);
5194 user_defined_result_ready:
5196 /* Free all the conversions we allocated. */
5197 obstack_free (&conversion_obstack, p);
5199 if (result || result_valid_p)
5203 avoid_sign_compare_warnings (orig_arg1, arg1);
5204 avoid_sign_compare_warnings (orig_arg2, arg2);
5205 avoid_sign_compare_warnings (orig_arg3, arg3);
5210 return cp_build_modify_expr (arg1, code2, arg2, complain);
5213 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
5215 case TRUTH_ANDIF_EXPR:
5216 case TRUTH_ORIF_EXPR:
5217 case TRUTH_AND_EXPR:
5219 warn_logical_operator (input_location, code, boolean_type_node,
5220 code_orig_arg1, arg1, code_orig_arg2, arg2);
5225 case TRUNC_DIV_EXPR:
5236 case TRUNC_MOD_EXPR:
5240 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
5242 case UNARY_PLUS_EXPR:
5245 case TRUTH_NOT_EXPR:
5246 case PREINCREMENT_EXPR:
5247 case POSTINCREMENT_EXPR:
5248 case PREDECREMENT_EXPR:
5249 case POSTDECREMENT_EXPR:
5253 return cp_build_unary_op (code, arg1, candidates != 0, complain);
5256 return cp_build_array_ref (input_location, arg1, arg2, complain);
5259 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
5263 /* The caller will deal with these. */
5275 /* Wrapper for above. */
5278 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
5279 tree *overload, tsubst_flags_t complain)
5282 bool subtime = timevar_cond_start (TV_OVERLOAD);
5283 ret = build_new_op_1 (code, flags, arg1, arg2, arg3, overload, complain);
5284 timevar_cond_stop (TV_OVERLOAD, subtime);
5288 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5289 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5292 non_placement_deallocation_fn_p (tree t)
5294 /* A template instance is never a usual deallocation function,
5295 regardless of its signature. */
5296 if (TREE_CODE (t) == TEMPLATE_DECL
5297 || primary_template_instantiation_p (t))
5300 /* If a class T has a member deallocation function named operator delete
5301 with exactly one parameter, then that function is a usual
5302 (non-placement) deallocation function. If class T does not declare
5303 such an operator delete but does declare a member deallocation
5304 function named operator delete with exactly two parameters, the second
5305 of which has type std::size_t (18.2), then this function is a usual
5306 deallocation function. */
5307 t = FUNCTION_ARG_CHAIN (t);
5308 if (t == void_list_node
5309 || (t && same_type_p (TREE_VALUE (t), size_type_node)
5310 && TREE_CHAIN (t) == void_list_node))
5315 /* Build a call to operator delete. This has to be handled very specially,
5316 because the restrictions on what signatures match are different from all
5317 other call instances. For a normal delete, only a delete taking (void *)
5318 or (void *, size_t) is accepted. For a placement delete, only an exact
5319 match with the placement new is accepted.
5321 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5322 ADDR is the pointer to be deleted.
5323 SIZE is the size of the memory block to be deleted.
5324 GLOBAL_P is true if the delete-expression should not consider
5325 class-specific delete operators.
5326 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5328 If this call to "operator delete" is being generated as part to
5329 deallocate memory allocated via a new-expression (as per [expr.new]
5330 which requires that if the initialization throws an exception then
5331 we call a deallocation function), then ALLOC_FN is the allocation
5335 build_op_delete_call (enum tree_code code, tree addr, tree size,
5336 bool global_p, tree placement,
5339 tree fn = NULL_TREE;
5340 tree fns, fnname, type, t;
5342 if (addr == error_mark_node)
5343 return error_mark_node;
5345 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
5347 fnname = ansi_opname (code);
5349 if (CLASS_TYPE_P (type)
5350 && COMPLETE_TYPE_P (complete_type (type))
5354 If the result of the lookup is ambiguous or inaccessible, or if
5355 the lookup selects a placement deallocation function, the
5356 program is ill-formed.
5358 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5360 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
5361 if (fns == error_mark_node)
5362 return error_mark_node;
5367 if (fns == NULL_TREE)
5368 fns = lookup_name_nonclass (fnname);
5370 /* Strip const and volatile from addr. */
5371 addr = cp_convert (ptr_type_node, addr);
5375 /* "A declaration of a placement deallocation function matches the
5376 declaration of a placement allocation function if it has the same
5377 number of parameters and, after parameter transformations (8.3.5),
5378 all parameter types except the first are identical."
5380 So we build up the function type we want and ask instantiate_type
5381 to get it for us. */
5382 t = FUNCTION_ARG_CHAIN (alloc_fn);
5383 t = tree_cons (NULL_TREE, ptr_type_node, t);
5384 t = build_function_type (void_type_node, t);
5386 fn = instantiate_type (t, fns, tf_none);
5387 if (fn == error_mark_node)
5390 if (BASELINK_P (fn))
5391 fn = BASELINK_FUNCTIONS (fn);
5393 /* "If the lookup finds the two-parameter form of a usual deallocation
5394 function (3.7.4.2) and that function, considered as a placement
5395 deallocation function, would have been selected as a match for the
5396 allocation function, the program is ill-formed." */
5397 if (non_placement_deallocation_fn_p (fn))
5399 /* But if the class has an operator delete (void *), then that is
5400 the usual deallocation function, so we shouldn't complain
5401 about using the operator delete (void *, size_t). */
5402 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5403 t; t = OVL_NEXT (t))
5405 tree elt = OVL_CURRENT (t);
5406 if (non_placement_deallocation_fn_p (elt)
5407 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
5410 permerror (0, "non-placement deallocation function %q+D", fn);
5411 permerror (input_location, "selected for placement delete");
5416 /* "Any non-placement deallocation function matches a non-placement
5417 allocation function. If the lookup finds a single matching
5418 deallocation function, that function will be called; otherwise, no
5419 deallocation function will be called." */
5420 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5421 t; t = OVL_NEXT (t))
5423 tree elt = OVL_CURRENT (t);
5424 if (non_placement_deallocation_fn_p (elt))
5427 /* "If a class T has a member deallocation function named
5428 operator delete with exactly one parameter, then that
5429 function is a usual (non-placement) deallocation
5430 function. If class T does not declare such an operator
5431 delete but does declare a member deallocation function named
5432 operator delete with exactly two parameters, the second of
5433 which has type std::size_t (18.2), then this function is a
5434 usual deallocation function."
5436 So (void*) beats (void*, size_t). */
5437 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
5442 /* If we have a matching function, call it. */
5445 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5447 /* If the FN is a member function, make sure that it is
5449 if (BASELINK_P (fns))
5450 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
5452 /* Core issue 901: It's ok to new a type with deleted delete. */
5453 if (DECL_DELETED_FN (fn) && alloc_fn)
5458 /* The placement args might not be suitable for overload
5459 resolution at this point, so build the call directly. */
5460 int nargs = call_expr_nargs (placement);
5461 tree *argarray = XALLOCAVEC (tree, nargs);
5464 for (i = 1; i < nargs; i++)
5465 argarray[i] = CALL_EXPR_ARG (placement, i);
5467 return build_cxx_call (fn, nargs, argarray);
5472 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
5473 VEC_quick_push (tree, args, addr);
5474 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
5475 VEC_quick_push (tree, args, size);
5476 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
5477 VEC_free (tree, gc, args);
5484 If no unambiguous matching deallocation function can be found,
5485 propagating the exception does not cause the object's memory to
5490 warning (0, "no corresponding deallocation function for %qD",
5495 error ("no suitable %<operator %s%> for %qT",
5496 operator_name_info[(int)code].name, type);
5497 return error_mark_node;
5500 /* If the current scope isn't allowed to access DECL along
5501 BASETYPE_PATH, give an error. The most derived class in
5502 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
5503 the declaration to use in the error diagnostic. */
5506 enforce_access (tree basetype_path, tree decl, tree diag_decl)
5508 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
5510 if (!accessible_p (basetype_path, decl, true))
5512 if (TREE_PRIVATE (decl))
5513 error ("%q+#D is private", diag_decl);
5514 else if (TREE_PROTECTED (decl))
5515 error ("%q+#D is protected", diag_decl);
5517 error ("%q+#D is inaccessible", diag_decl);
5518 error ("within this context");
5525 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
5526 bitwise or of LOOKUP_* values. If any errors are warnings are
5527 generated, set *DIAGNOSTIC_FN to "error" or "warning",
5528 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
5532 build_temp (tree expr, tree type, int flags,
5533 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
5538 savew = warningcount, savee = errorcount;
5539 args = make_tree_vector_single (expr);
5540 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
5541 &args, type, flags, complain);
5542 release_tree_vector (args);
5543 if (warningcount > savew)
5544 *diagnostic_kind = DK_WARNING;
5545 else if (errorcount > savee)
5546 *diagnostic_kind = DK_ERROR;
5548 *diagnostic_kind = DK_UNSPECIFIED;
5552 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
5553 EXPR is implicitly converted to type TOTYPE.
5554 FN and ARGNUM are used for diagnostics. */
5557 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
5559 /* Issue warnings about peculiar, but valid, uses of NULL. */
5560 if (expr == null_node && TREE_CODE (totype) != BOOLEAN_TYPE
5561 && ARITHMETIC_TYPE_P (totype))
5564 warning_at (input_location, OPT_Wconversion_null,
5565 "passing NULL to non-pointer argument %P of %qD",
5568 warning_at (input_location, OPT_Wconversion_null,
5569 "converting to non-pointer type %qT from NULL", totype);
5572 /* Issue warnings if "false" is converted to a NULL pointer */
5573 else if (TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE
5574 && TYPE_PTR_P (totype))
5577 warning_at (input_location, OPT_Wconversion_null,
5578 "converting %<false%> to pointer type for argument %P "
5579 "of %qD", argnum, fn);
5581 warning_at (input_location, OPT_Wconversion_null,
5582 "converting %<false%> to pointer type %qT", totype);
5586 /* Perform the conversions in CONVS on the expression EXPR. FN and
5587 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
5588 indicates the `this' argument of a method. INNER is nonzero when
5589 being called to continue a conversion chain. It is negative when a
5590 reference binding will be applied, positive otherwise. If
5591 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
5592 conversions will be emitted if appropriate. If C_CAST_P is true,
5593 this conversion is coming from a C-style cast; in that case,
5594 conversions to inaccessible bases are permitted. */
5597 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
5598 int inner, bool issue_conversion_warnings,
5599 bool c_cast_p, tsubst_flags_t complain)
5601 tree totype = convs->type;
5602 diagnostic_t diag_kind;
5605 if (convs->bad_p && !(complain & tf_error))
5606 return error_mark_node;
5609 && convs->kind != ck_user
5610 && convs->kind != ck_list
5611 && convs->kind != ck_ambig
5612 && (convs->kind != ck_ref_bind
5613 || convs->user_conv_p)
5614 && convs->kind != ck_rvalue
5615 && convs->kind != ck_base)
5617 conversion *t = convs;
5619 /* Give a helpful error if this is bad because of excess braces. */
5620 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5621 && SCALAR_TYPE_P (totype)
5622 && CONSTRUCTOR_NELTS (expr) > 0
5623 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
5624 permerror (input_location, "too many braces around initializer for %qT", totype);
5626 for (; t ; t = next_conversion (t))
5628 if (t->kind == ck_user && t->cand->reason)
5630 permerror (input_location, "invalid user-defined conversion "
5631 "from %qT to %qT", TREE_TYPE (expr), totype);
5632 print_z_candidate ("candidate is:", t->cand);
5633 expr = convert_like_real (t, expr, fn, argnum, 1,
5634 /*issue_conversion_warnings=*/false,
5637 if (convs->kind == ck_ref_bind)
5638 return convert_to_reference (totype, expr, CONV_IMPLICIT,
5639 LOOKUP_NORMAL, NULL_TREE);
5641 return cp_convert (totype, expr);
5643 else if (t->kind == ck_user || !t->bad_p)
5645 expr = convert_like_real (t, expr, fn, argnum, 1,
5646 /*issue_conversion_warnings=*/false,
5651 else if (t->kind == ck_ambig)
5652 return convert_like_real (t, expr, fn, argnum, 1,
5653 /*issue_conversion_warnings=*/false,
5656 else if (t->kind == ck_identity)
5660 permerror (input_location, "invalid conversion from %qT to %qT",
5661 TREE_TYPE (expr), totype);
5663 permerror (DECL_SOURCE_LOCATION (fn),
5664 " initializing argument %P of %qD", argnum, fn);
5666 return cp_convert (totype, expr);
5669 if (issue_conversion_warnings && (complain & tf_warning))
5670 conversion_null_warnings (totype, expr, fn, argnum);
5672 switch (convs->kind)
5676 struct z_candidate *cand = convs->cand;
5677 tree convfn = cand->fn;
5680 /* If we're initializing from {}, it's value-initialization. */
5681 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5682 && CONSTRUCTOR_NELTS (expr) == 0
5683 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
5685 bool direct = CONSTRUCTOR_IS_DIRECT_INIT (expr);
5686 expr = build_value_init (totype, complain);
5687 expr = get_target_expr_sfinae (expr, complain);
5688 if (expr != error_mark_node)
5690 TARGET_EXPR_LIST_INIT_P (expr) = true;
5691 TARGET_EXPR_DIRECT_INIT_P (expr) = direct;
5696 expr = mark_rvalue_use (expr);
5698 /* When converting from an init list we consider explicit
5699 constructors, but actually trying to call one is an error. */
5700 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
5701 /* Unless this is for direct-list-initialization. */
5702 && !(BRACE_ENCLOSED_INITIALIZER_P (expr)
5703 && CONSTRUCTOR_IS_DIRECT_INIT (expr))
5704 /* Unless we're calling it for value-initialization from an
5705 empty list, since that is handled separately in 8.5.4. */
5706 && cand->num_convs > 0)
5708 error ("converting to %qT from initializer list would use "
5709 "explicit constructor %qD", totype, convfn);
5712 /* Set user_conv_p on the argument conversions, so rvalue/base
5713 handling knows not to allow any more UDCs. */
5714 for (i = 0; i < cand->num_convs; ++i)
5715 cand->convs[i]->user_conv_p = true;
5717 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
5719 /* If this is a constructor or a function returning an aggr type,
5720 we need to build up a TARGET_EXPR. */
5721 if (DECL_CONSTRUCTOR_P (convfn))
5723 expr = build_cplus_new (totype, expr, complain);
5725 /* Remember that this was list-initialization. */
5726 if (convs->check_narrowing && expr != error_mark_node)
5727 TARGET_EXPR_LIST_INIT_P (expr) = true;
5733 expr = mark_rvalue_use (expr);
5734 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
5736 int nelts = CONSTRUCTOR_NELTS (expr);
5738 expr = build_value_init (totype, complain);
5739 else if (nelts == 1)
5740 expr = CONSTRUCTOR_ELT (expr, 0)->value;
5745 if (type_unknown_p (expr))
5746 expr = instantiate_type (totype, expr, complain);
5747 /* Convert a constant to its underlying value, unless we are
5748 about to bind it to a reference, in which case we need to
5749 leave it as an lvalue. */
5752 expr = decl_constant_value_safe (expr);
5753 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
5754 /* If __null has been converted to an integer type, we do not
5755 want to warn about uses of EXPR as an integer, rather than
5757 expr = build_int_cst (totype, 0);
5761 /* We leave bad_p off ck_ambig because overload resolution considers
5762 it valid, it just fails when we try to perform it. So we need to
5763 check complain here, too. */
5764 if (complain & tf_error)
5766 /* Call build_user_type_conversion again for the error. */
5767 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL);
5769 error (" initializing argument %P of %q+D", argnum, fn);
5771 return error_mark_node;
5775 /* Conversion to std::initializer_list<T>. */
5776 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
5777 tree new_ctor = build_constructor (init_list_type_node, NULL);
5778 unsigned len = CONSTRUCTOR_NELTS (expr);
5779 tree array, val, field;
5780 VEC(constructor_elt,gc) *vec = NULL;
5783 /* Convert all the elements. */
5784 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
5786 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
5787 1, false, false, complain);
5788 if (sub == error_mark_node)
5790 if (!BRACE_ENCLOSED_INITIALIZER_P (val))
5791 check_narrowing (TREE_TYPE (sub), val);
5792 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
5793 if (!TREE_CONSTANT (sub))
5794 TREE_CONSTANT (new_ctor) = false;
5796 /* Build up the array. */
5797 elttype = cp_build_qualified_type
5798 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
5799 array = build_array_of_n_type (elttype, len);
5800 array = finish_compound_literal (array, new_ctor, complain);
5802 /* Build up the initializer_list object. */
5803 totype = complete_type (totype);
5804 field = next_initializable_field (TYPE_FIELDS (totype));
5805 CONSTRUCTOR_APPEND_ELT (vec, field, decay_conversion (array));
5806 field = next_initializable_field (DECL_CHAIN (field));
5807 CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len));
5808 new_ctor = build_constructor (totype, vec);
5809 return get_target_expr (new_ctor);
5813 if (TREE_CODE (totype) == COMPLEX_TYPE)
5815 tree real = CONSTRUCTOR_ELT (expr, 0)->value;
5816 tree imag = CONSTRUCTOR_ELT (expr, 1)->value;
5817 real = perform_implicit_conversion (TREE_TYPE (totype),
5819 imag = perform_implicit_conversion (TREE_TYPE (totype),
5821 expr = build2 (COMPLEX_EXPR, totype, real, imag);
5822 return fold_if_not_in_template (expr);
5824 return get_target_expr (digest_init (totype, expr, complain));
5830 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5831 convs->kind == ck_ref_bind ? -1 : 1,
5832 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5835 if (expr == error_mark_node)
5836 return error_mark_node;
5838 switch (convs->kind)
5841 expr = decay_conversion (expr);
5842 if (! MAYBE_CLASS_TYPE_P (totype))
5844 /* Else fall through. */
5846 if (convs->kind == ck_base && !convs->need_temporary_p)
5848 /* We are going to bind a reference directly to a base-class
5849 subobject of EXPR. */
5850 /* Build an expression for `*((base*) &expr)'. */
5851 expr = cp_build_addr_expr (expr, complain);
5852 expr = convert_to_base (expr, build_pointer_type (totype),
5853 !c_cast_p, /*nonnull=*/true, complain);
5854 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5858 /* Copy-initialization where the cv-unqualified version of the source
5859 type is the same class as, or a derived class of, the class of the
5860 destination [is treated as direct-initialization]. [dcl.init] */
5861 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5862 if (convs->user_conv_p)
5863 /* This conversion is being done in the context of a user-defined
5864 conversion (i.e. the second step of copy-initialization), so
5865 don't allow any more. */
5866 flags |= LOOKUP_NO_CONVERSION;
5867 if (convs->rvaluedness_matches_p)
5868 flags |= LOOKUP_PREFER_RVALUE;
5869 if (TREE_CODE (expr) == TARGET_EXPR
5870 && TARGET_EXPR_LIST_INIT_P (expr))
5871 /* Copy-list-initialization doesn't actually involve a copy. */
5873 expr = build_temp (expr, totype, flags, &diag_kind, complain);
5874 if (diag_kind && fn && complain)
5875 emit_diagnostic (diag_kind, DECL_SOURCE_LOCATION (fn), 0,
5876 " initializing argument %P of %qD", argnum, fn);
5877 return build_cplus_new (totype, expr, complain);
5881 tree ref_type = totype;
5883 if (convs->bad_p && !convs->u.next->bad_p)
5885 gcc_assert (TYPE_REF_IS_RVALUE (ref_type)
5886 && real_lvalue_p (expr));
5888 error ("cannot bind %qT lvalue to %qT",
5889 TREE_TYPE (expr), totype);
5891 error (" initializing argument %P of %q+D", argnum, fn);
5892 return error_mark_node;
5895 /* If necessary, create a temporary.
5897 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5898 that need temporaries, even when their types are reference
5899 compatible with the type of reference being bound, so the
5900 upcoming call to cp_build_addr_expr doesn't fail. */
5901 if (convs->need_temporary_p
5902 || TREE_CODE (expr) == CONSTRUCTOR
5903 || TREE_CODE (expr) == VA_ARG_EXPR)
5905 /* Otherwise, a temporary of type "cv1 T1" is created and
5906 initialized from the initializer expression using the rules
5907 for a non-reference copy-initialization (8.5). */
5909 tree type = TREE_TYPE (ref_type);
5910 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5912 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5913 (type, convs->u.next->type));
5914 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
5915 && !TYPE_REF_IS_RVALUE (ref_type))
5917 /* If the reference is volatile or non-const, we
5918 cannot create a temporary. */
5919 if (lvalue & clk_bitfield)
5920 error ("cannot bind bitfield %qE to %qT",
5922 else if (lvalue & clk_packed)
5923 error ("cannot bind packed field %qE to %qT",
5926 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5927 return error_mark_node;
5929 /* If the source is a packed field, and we must use a copy
5930 constructor, then building the target expr will require
5931 binding the field to the reference parameter to the
5932 copy constructor, and we'll end up with an infinite
5933 loop. If we can use a bitwise copy, then we'll be
5935 if ((lvalue & clk_packed)
5936 && CLASS_TYPE_P (type)
5937 && type_has_nontrivial_copy_init (type))
5939 error ("cannot bind packed field %qE to %qT",
5941 return error_mark_node;
5943 if (lvalue & clk_bitfield)
5945 expr = convert_bitfield_to_declared_type (expr);
5946 expr = fold_convert (type, expr);
5948 expr = build_target_expr_with_type (expr, type, complain);
5951 /* Take the address of the thing to which we will bind the
5953 expr = cp_build_addr_expr (expr, complain);
5954 if (expr == error_mark_node)
5955 return error_mark_node;
5957 /* Convert it to a pointer to the type referred to by the
5958 reference. This will adjust the pointer if a derived to
5959 base conversion is being performed. */
5960 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5962 /* Convert the pointer to the desired reference type. */
5963 return build_nop (ref_type, expr);
5967 return decay_conversion (expr);
5970 /* Warn about deprecated conversion if appropriate. */
5971 string_conv_p (totype, expr, 1);
5976 expr = convert_to_base (expr, totype, !c_cast_p,
5977 /*nonnull=*/false, complain);
5978 return build_nop (totype, expr);
5981 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5982 c_cast_p, complain);
5988 if (convs->check_narrowing)
5989 check_narrowing (totype, expr);
5991 if (issue_conversion_warnings && (complain & tf_warning))
5992 expr = convert_and_check (totype, expr);
5994 expr = convert (totype, expr);
5999 /* ARG is being passed to a varargs function. Perform any conversions
6000 required. Return the converted value. */
6003 convert_arg_to_ellipsis (tree arg)
6009 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6010 standard conversions are performed. */
6011 arg = decay_conversion (arg);
6012 arg_type = TREE_TYPE (arg);
6015 If the argument has integral or enumeration type that is subject
6016 to the integral promotions (_conv.prom_), or a floating point
6017 type that is subject to the floating point promotion
6018 (_conv.fpprom_), the value of the argument is converted to the
6019 promoted type before the call. */
6020 if (TREE_CODE (arg_type) == REAL_TYPE
6021 && (TYPE_PRECISION (arg_type)
6022 < TYPE_PRECISION (double_type_node))
6023 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
6025 if (warn_double_promotion && !c_inhibit_evaluation_warnings)
6026 warning (OPT_Wdouble_promotion,
6027 "implicit conversion from %qT to %qT when passing "
6028 "argument to function",
6029 arg_type, double_type_node);
6030 arg = convert_to_real (double_type_node, arg);
6032 else if (NULLPTR_TYPE_P (arg_type))
6033 arg = null_pointer_node;
6034 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
6036 if (SCOPED_ENUM_P (arg_type) && !abi_version_at_least (6))
6038 warning (OPT_Wabi, "scoped enum %qT will not promote to an "
6039 "integral type in a future version of GCC", arg_type);
6040 arg = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg);
6042 arg = perform_integral_promotions (arg);
6045 arg = require_complete_type (arg);
6046 arg_type = TREE_TYPE (arg);
6048 if (arg != error_mark_node
6049 /* In a template (or ill-formed code), we can have an incomplete type
6050 even after require_complete_type, in which case we don't know
6051 whether it has trivial copy or not. */
6052 && COMPLETE_TYPE_P (arg_type))
6054 /* Build up a real lvalue-to-rvalue conversion in case the
6055 copy constructor is trivial but not callable. */
6056 if (!cp_unevaluated_operand && CLASS_TYPE_P (arg_type))
6057 force_rvalue (arg, tf_warning_or_error);
6059 /* [expr.call] 5.2.2/7:
6060 Passing a potentially-evaluated argument of class type (Clause 9)
6061 with a non-trivial copy constructor or a non-trivial destructor
6062 with no corresponding parameter is conditionally-supported, with
6063 implementation-defined semantics.
6065 We used to just warn here and do a bitwise copy, but now
6066 cp_expr_size will abort if we try to do that.
6068 If the call appears in the context of a sizeof expression,
6069 it is not potentially-evaluated. */
6070 if (cp_unevaluated_operand == 0
6071 && (type_has_nontrivial_copy_init (arg_type)
6072 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
6073 error ("cannot pass objects of non-trivially-copyable "
6074 "type %q#T through %<...%>", arg_type);
6080 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6083 build_x_va_arg (tree expr, tree type)
6085 if (processing_template_decl)
6086 return build_min (VA_ARG_EXPR, type, expr);
6088 type = complete_type_or_else (type, NULL_TREE);
6090 if (expr == error_mark_node || !type)
6091 return error_mark_node;
6093 expr = mark_lvalue_use (expr);
6095 if (type_has_nontrivial_copy_init (type)
6096 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
6097 || TREE_CODE (type) == REFERENCE_TYPE)
6099 /* Remove reference types so we don't ICE later on. */
6100 tree type1 = non_reference (type);
6101 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
6102 error ("cannot receive objects of non-trivially-copyable type %q#T "
6103 "through %<...%>; ", type);
6104 expr = convert (build_pointer_type (type1), null_node);
6105 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
6109 return build_va_arg (input_location, expr, type);
6112 /* TYPE has been given to va_arg. Apply the default conversions which
6113 would have happened when passed via ellipsis. Return the promoted
6114 type, or the passed type if there is no change. */
6117 cxx_type_promotes_to (tree type)
6121 /* Perform the array-to-pointer and function-to-pointer
6123 type = type_decays_to (type);
6125 promote = type_promotes_to (type);
6126 if (same_type_p (type, promote))
6132 /* ARG is a default argument expression being passed to a parameter of
6133 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6134 zero-based argument number. Do any required conversions. Return
6135 the converted value. */
6137 static GTY(()) VEC(tree,gc) *default_arg_context;
6139 push_defarg_context (tree fn)
6140 { VEC_safe_push (tree, gc, default_arg_context, fn); }
6142 pop_defarg_context (void)
6143 { VEC_pop (tree, default_arg_context); }
6146 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
6151 /* See through clones. */
6152 fn = DECL_ORIGIN (fn);
6154 /* Detect recursion. */
6155 FOR_EACH_VEC_ELT (tree, default_arg_context, i, t)
6158 error ("recursive evaluation of default argument for %q#D", fn);
6159 return error_mark_node;
6162 /* If the ARG is an unparsed default argument expression, the
6163 conversion cannot be performed. */
6164 if (TREE_CODE (arg) == DEFAULT_ARG)
6166 error ("call to %qD uses the default argument for parameter %P, which "
6167 "is not yet defined", fn, parmnum);
6168 return error_mark_node;
6171 push_defarg_context (fn);
6173 if (fn && DECL_TEMPLATE_INFO (fn))
6174 arg = tsubst_default_argument (fn, type, arg);
6180 The names in the expression are bound, and the semantic
6181 constraints are checked, at the point where the default
6182 expressions appears.
6184 we must not perform access checks here. */
6185 push_deferring_access_checks (dk_no_check);
6186 /* We must make a copy of ARG, in case subsequent processing
6187 alters any part of it. */
6188 arg = break_out_target_exprs (arg);
6189 if (TREE_CODE (arg) == CONSTRUCTOR)
6191 arg = digest_init (type, arg, tf_warning_or_error);
6192 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6193 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6194 tf_warning_or_error);
6198 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6199 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6200 tf_warning_or_error);
6201 arg = convert_for_arg_passing (type, arg);
6203 pop_deferring_access_checks();
6205 pop_defarg_context ();
6210 /* Returns the type which will really be used for passing an argument of
6214 type_passed_as (tree type)
6216 /* Pass classes with copy ctors by invisible reference. */
6217 if (TREE_ADDRESSABLE (type))
6219 type = build_reference_type (type);
6220 /* There are no other pointers to this temporary. */
6221 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
6223 else if (targetm.calls.promote_prototypes (type)
6224 && INTEGRAL_TYPE_P (type)
6225 && COMPLETE_TYPE_P (type)
6226 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6227 TYPE_SIZE (integer_type_node)))
6228 type = integer_type_node;
6233 /* Actually perform the appropriate conversion. */
6236 convert_for_arg_passing (tree type, tree val)
6240 /* If VAL is a bitfield, then -- since it has already been converted
6241 to TYPE -- it cannot have a precision greater than TYPE.
6243 If it has a smaller precision, we must widen it here. For
6244 example, passing "int f:3;" to a function expecting an "int" will
6245 not result in any conversion before this point.
6247 If the precision is the same we must not risk widening. For
6248 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6249 often have type "int", even though the C++ type for the field is
6250 "long long". If the value is being passed to a function
6251 expecting an "int", then no conversions will be required. But,
6252 if we call convert_bitfield_to_declared_type, the bitfield will
6253 be converted to "long long". */
6254 bitfield_type = is_bitfield_expr_with_lowered_type (val);
6256 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
6257 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
6259 if (val == error_mark_node)
6261 /* Pass classes with copy ctors by invisible reference. */
6262 else if (TREE_ADDRESSABLE (type))
6263 val = build1 (ADDR_EXPR, build_reference_type (type), val);
6264 else if (targetm.calls.promote_prototypes (type)
6265 && INTEGRAL_TYPE_P (type)
6266 && COMPLETE_TYPE_P (type)
6267 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6268 TYPE_SIZE (integer_type_node)))
6269 val = perform_integral_promotions (val);
6270 if (warn_missing_format_attribute)
6272 tree rhstype = TREE_TYPE (val);
6273 const enum tree_code coder = TREE_CODE (rhstype);
6274 const enum tree_code codel = TREE_CODE (type);
6275 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6277 && check_missing_format_attribute (type, rhstype))
6278 warning (OPT_Wmissing_format_attribute,
6279 "argument of function call might be a candidate for a format attribute");
6284 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6285 which no conversions at all should be done. This is true for some
6286 builtins which don't act like normal functions. */
6289 magic_varargs_p (tree fn)
6291 if (DECL_BUILT_IN (fn))
6292 switch (DECL_FUNCTION_CODE (fn))
6294 case BUILT_IN_CLASSIFY_TYPE:
6295 case BUILT_IN_CONSTANT_P:
6296 case BUILT_IN_NEXT_ARG:
6297 case BUILT_IN_VA_START:
6301 return lookup_attribute ("type generic",
6302 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
6308 /* Subroutine of the various build_*_call functions. Overload resolution
6309 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
6310 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
6311 bitmask of various LOOKUP_* flags which apply to the call itself. */
6314 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
6317 const VEC(tree,gc) *args = cand->args;
6318 tree first_arg = cand->first_arg;
6319 conversion **convs = cand->convs;
6321 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
6326 unsigned int arg_index = 0;
6330 bool already_used = false;
6332 /* In a template, there is no need to perform all of the work that
6333 is normally done. We are only interested in the type of the call
6334 expression, i.e., the return type of the function. Any semantic
6335 errors will be deferred until the template is instantiated. */
6336 if (processing_template_decl)
6340 const tree *argarray;
6343 return_type = TREE_TYPE (TREE_TYPE (fn));
6344 nargs = VEC_length (tree, args);
6345 if (first_arg == NULL_TREE)
6346 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
6354 alcarray = XALLOCAVEC (tree, nargs);
6355 alcarray[0] = first_arg;
6356 FOR_EACH_VEC_ELT (tree, args, ix, arg)
6357 alcarray[ix + 1] = arg;
6358 argarray = alcarray;
6360 expr = build_call_array_loc (input_location,
6361 return_type, build_addr_func (fn), nargs,
6363 if (TREE_THIS_VOLATILE (fn) && cfun)
6364 current_function_returns_abnormally = 1;
6365 return convert_from_reference (expr);
6368 /* Give any warnings we noticed during overload resolution. */
6369 if (cand->warnings && (complain & tf_warning))
6371 struct candidate_warning *w;
6372 for (w = cand->warnings; w; w = w->next)
6373 joust (cand, w->loser, 1);
6376 /* Make =delete work with SFINAE. */
6377 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
6378 return error_mark_node;
6380 if (DECL_FUNCTION_MEMBER_P (fn))
6383 /* If FN is a template function, two cases must be considered.
6388 template <class T> void f();
6390 template <class T> struct B {
6394 struct C : A, B<int> {
6396 using B<int>::g; // #2
6399 In case #1 where `A::f' is a member template, DECL_ACCESS is
6400 recorded in the primary template but not in its specialization.
6401 We check access of FN using its primary template.
6403 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
6404 because it is a member of class template B, DECL_ACCESS is
6405 recorded in the specialization `B<int>::g'. We cannot use its
6406 primary template because `B<T>::g' and `B<int>::g' may have
6407 different access. */
6408 if (DECL_TEMPLATE_INFO (fn)
6409 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
6410 access_fn = DECL_TI_TEMPLATE (fn);
6413 if (flags & LOOKUP_SPECULATIVE)
6415 if (!speculative_access_check (cand->access_path, access_fn, fn,
6416 !!(flags & LOOKUP_COMPLAIN)))
6417 return error_mark_node;
6420 perform_or_defer_access_check (cand->access_path, access_fn, fn);
6423 /* If we're checking for implicit delete, don't bother with argument
6425 if (flags & LOOKUP_SPECULATIVE)
6427 if (DECL_DELETED_FN (fn))
6429 if (flags & LOOKUP_COMPLAIN)
6431 return error_mark_node;
6433 if (cand->viable == 1)
6435 else if (!(flags & LOOKUP_COMPLAIN))
6436 /* Reject bad conversions now. */
6437 return error_mark_node;
6438 /* else continue to get conversion error. */
6441 /* Find maximum size of vector to hold converted arguments. */
6442 parmlen = list_length (parm);
6443 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
6444 if (parmlen > nargs)
6446 argarray = XALLOCAVEC (tree, nargs);
6448 /* The implicit parameters to a constructor are not considered by overload
6449 resolution, and must be of the proper type. */
6450 if (DECL_CONSTRUCTOR_P (fn))
6452 if (first_arg != NULL_TREE)
6454 argarray[j++] = first_arg;
6455 first_arg = NULL_TREE;
6459 argarray[j++] = VEC_index (tree, args, arg_index);
6462 parm = TREE_CHAIN (parm);
6463 /* We should never try to call the abstract constructor. */
6464 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
6466 if (DECL_HAS_VTT_PARM_P (fn))
6468 argarray[j++] = VEC_index (tree, args, arg_index);
6470 parm = TREE_CHAIN (parm);
6473 /* Bypass access control for 'this' parameter. */
6474 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6476 tree parmtype = TREE_VALUE (parm);
6477 tree arg = (first_arg != NULL_TREE
6479 : VEC_index (tree, args, arg_index));
6480 tree argtype = TREE_TYPE (arg);
6484 if (convs[i]->bad_p)
6486 if (complain & tf_error)
6487 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
6488 TREE_TYPE (argtype), fn);
6490 return error_mark_node;
6493 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
6494 X is called for an object that is not of type X, or of a type
6495 derived from X, the behavior is undefined.
6497 So we can assume that anything passed as 'this' is non-null, and
6498 optimize accordingly. */
6499 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
6500 /* Convert to the base in which the function was declared. */
6501 gcc_assert (cand->conversion_path != NULL_TREE);
6502 converted_arg = build_base_path (PLUS_EXPR,
6504 cand->conversion_path,
6506 /* Check that the base class is accessible. */
6507 if (!accessible_base_p (TREE_TYPE (argtype),
6508 BINFO_TYPE (cand->conversion_path), true))
6509 error ("%qT is not an accessible base of %qT",
6510 BINFO_TYPE (cand->conversion_path),
6511 TREE_TYPE (argtype));
6512 /* If fn was found by a using declaration, the conversion path
6513 will be to the derived class, not the base declaring fn. We
6514 must convert from derived to base. */
6515 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
6516 TREE_TYPE (parmtype), ba_unique, NULL);
6517 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
6518 base_binfo, 1, complain);
6520 argarray[j++] = converted_arg;
6521 parm = TREE_CHAIN (parm);
6522 if (first_arg != NULL_TREE)
6523 first_arg = NULL_TREE;
6530 gcc_assert (first_arg == NULL_TREE);
6531 for (; arg_index < VEC_length (tree, args) && parm;
6532 parm = TREE_CHAIN (parm), ++arg_index, ++i)
6534 tree type = TREE_VALUE (parm);
6535 tree arg = VEC_index (tree, args, arg_index);
6536 bool conversion_warning = true;
6540 /* If the argument is NULL and used to (implicitly) instantiate a
6541 template function (and bind one of the template arguments to
6542 the type of 'long int'), we don't want to warn about passing NULL
6543 to non-pointer argument.
6544 For example, if we have this template function:
6546 template<typename T> void func(T x) {}
6548 we want to warn (when -Wconversion is enabled) in this case:
6554 but not in this case:
6560 if (arg == null_node
6561 && DECL_TEMPLATE_INFO (fn)
6562 && cand->template_decl
6563 && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS))
6564 conversion_warning = false;
6566 /* Warn about initializer_list deduction that isn't currently in the
6568 if (cxx_dialect > cxx98
6569 && flag_deduce_init_list
6570 && cand->template_decl
6571 && is_std_init_list (non_reference (type))
6572 && BRACE_ENCLOSED_INITIALIZER_P (arg))
6574 tree tmpl = TI_TEMPLATE (cand->template_decl);
6575 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
6576 tree patparm = get_pattern_parm (realparm, tmpl);
6577 tree pattype = TREE_TYPE (patparm);
6578 if (PACK_EXPANSION_P (pattype))
6579 pattype = PACK_EXPANSION_PATTERN (pattype);
6580 pattype = non_reference (pattype);
6582 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
6583 && (cand->explicit_targs == NULL_TREE
6584 || (TREE_VEC_LENGTH (cand->explicit_targs)
6585 <= TEMPLATE_TYPE_IDX (pattype))))
6587 pedwarn (input_location, 0, "deducing %qT as %qT",
6588 non_reference (TREE_TYPE (patparm)),
6589 non_reference (type));
6590 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
6591 pedwarn (input_location, 0,
6592 " (you can disable this with -fno-deduce-init-list)");
6596 val = convert_like_with_context (conv, arg, fn, i-is_method,
6599 : complain & (~tf_warning));
6601 val = convert_for_arg_passing (type, val);
6602 if (val == error_mark_node)
6603 return error_mark_node;
6605 argarray[j++] = val;
6608 /* Default arguments */
6609 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
6610 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
6611 TREE_PURPOSE (parm),
6614 for (; arg_index < VEC_length (tree, args); ++arg_index)
6616 tree a = VEC_index (tree, args, arg_index);
6617 if (magic_varargs_p (fn))
6618 /* Do no conversions for magic varargs. */
6619 a = mark_type_use (a);
6621 a = convert_arg_to_ellipsis (a);
6625 gcc_assert (j <= nargs);
6628 check_function_arguments (TREE_TYPE (fn), nargs, argarray);
6630 /* Avoid actually calling copy constructors and copy assignment operators,
6633 if (! flag_elide_constructors)
6634 /* Do things the hard way. */;
6635 else if (cand->num_convs == 1
6636 && (DECL_COPY_CONSTRUCTOR_P (fn)
6637 || DECL_MOVE_CONSTRUCTOR_P (fn)))
6640 tree arg = argarray[num_artificial_parms_for (fn)];
6642 bool trivial = trivial_fn_p (fn);
6644 /* Pull out the real argument, disregarding const-correctness. */
6646 while (CONVERT_EXPR_P (targ)
6647 || TREE_CODE (targ) == NON_LVALUE_EXPR)
6648 targ = TREE_OPERAND (targ, 0);
6649 if (TREE_CODE (targ) == ADDR_EXPR)
6651 targ = TREE_OPERAND (targ, 0);
6652 if (!same_type_ignoring_top_level_qualifiers_p
6653 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
6662 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6664 /* [class.copy]: the copy constructor is implicitly defined even if
6665 the implementation elided its use. */
6666 if (!trivial || DECL_DELETED_FN (fn))
6669 already_used = true;
6672 /* If we're creating a temp and we already have one, don't create a
6673 new one. If we're not creating a temp but we get one, use
6674 INIT_EXPR to collapse the temp into our target. Otherwise, if the
6675 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
6676 temp or an INIT_EXPR otherwise. */
6678 if (integer_zerop (fa))
6680 if (TREE_CODE (arg) == TARGET_EXPR)
6683 return force_target_expr (DECL_CONTEXT (fn), arg, complain);
6685 else if (TREE_CODE (arg) == TARGET_EXPR || trivial)
6687 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
6690 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
6694 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
6695 && trivial_fn_p (fn)
6696 && !DECL_DELETED_FN (fn))
6698 tree to = stabilize_reference
6699 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
6700 tree type = TREE_TYPE (to);
6701 tree as_base = CLASSTYPE_AS_BASE (type);
6702 tree arg = argarray[1];
6704 if (is_really_empty_class (type))
6706 /* Avoid copying empty classes. */
6707 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
6708 TREE_NO_WARNING (val) = 1;
6709 val = build2 (COMPOUND_EXPR, type, val, to);
6710 TREE_NO_WARNING (val) = 1;
6712 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
6714 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6715 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
6719 /* We must only copy the non-tail padding parts. */
6721 tree array_type, alias_set;
6723 arg2 = TYPE_SIZE_UNIT (as_base);
6724 arg0 = cp_build_addr_expr (to, complain);
6726 array_type = build_array_type (char_type_node,
6728 (size_binop (MINUS_EXPR,
6729 arg2, size_int (1))));
6730 alias_set = build_int_cst (build_pointer_type (type), 0);
6731 t = build2 (MODIFY_EXPR, void_type_node,
6732 build2 (MEM_REF, array_type, arg0, alias_set),
6733 build2 (MEM_REF, array_type, arg, alias_set));
6734 val = build2 (COMPOUND_EXPR, TREE_TYPE (to), t, to);
6735 TREE_NO_WARNING (val) = 1;
6740 else if (DECL_DESTRUCTOR_P (fn)
6741 && trivial_fn_p (fn)
6742 && !DECL_DELETED_FN (fn))
6743 return fold_convert (void_type_node, argarray[0]);
6744 /* FIXME handle trivial default constructor, too. */
6749 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
6752 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
6755 gcc_assert (binfo && binfo != error_mark_node);
6757 /* Warn about deprecated virtual functions now, since we're about
6758 to throw away the decl. */
6759 if (TREE_DEPRECATED (fn))
6760 warn_deprecated_use (fn, NULL_TREE);
6762 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1,
6764 if (TREE_SIDE_EFFECTS (argarray[0]))
6765 argarray[0] = save_expr (argarray[0]);
6766 t = build_pointer_type (TREE_TYPE (fn));
6767 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
6768 fn = build_java_interface_fn_ref (fn, argarray[0]);
6770 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
6774 fn = build_addr_func (fn);
6776 return build_cxx_call (fn, nargs, argarray);
6779 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
6780 This function performs no overload resolution, conversion, or other
6781 high-level operations. */
6784 build_cxx_call (tree fn, int nargs, tree *argarray)
6788 /* Remember roughly where this call is. */
6789 location_t loc = EXPR_LOC_OR_HERE (fn);
6790 fn = build_call_a (fn, nargs, argarray);
6791 SET_EXPR_LOCATION (fn, loc);
6793 fndecl = get_callee_fndecl (fn);
6795 /* Check that arguments to builtin functions match the expectations. */
6797 && DECL_BUILT_IN (fndecl)
6798 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6799 && !check_builtin_function_arguments (fndecl, nargs, argarray))
6800 return error_mark_node;
6802 /* Some built-in function calls will be evaluated at compile-time in
6804 fn = fold_if_not_in_template (fn);
6806 if (VOID_TYPE_P (TREE_TYPE (fn)))
6809 fn = require_complete_type (fn);
6810 if (fn == error_mark_node)
6811 return error_mark_node;
6813 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
6814 fn = build_cplus_new (TREE_TYPE (fn), fn, tf_warning_or_error);
6815 return convert_from_reference (fn);
6818 static GTY(()) tree java_iface_lookup_fn;
6820 /* Make an expression which yields the address of the Java interface
6821 method FN. This is achieved by generating a call to libjava's
6822 _Jv_LookupInterfaceMethodIdx(). */
6825 build_java_interface_fn_ref (tree fn, tree instance)
6827 tree lookup_fn, method, idx;
6828 tree klass_ref, iface, iface_ref;
6831 if (!java_iface_lookup_fn)
6833 tree ftype = build_function_type_list (ptr_type_node,
6834 ptr_type_node, ptr_type_node,
6835 java_int_type_node, NULL_TREE);
6836 java_iface_lookup_fn
6837 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
6838 0, NOT_BUILT_IN, NULL, NULL_TREE);
6841 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
6842 This is the first entry in the vtable. */
6843 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
6844 tf_warning_or_error),
6847 /* Get the java.lang.Class pointer for the interface being called. */
6848 iface = DECL_CONTEXT (fn);
6849 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
6850 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
6851 || DECL_CONTEXT (iface_ref) != iface)
6853 error ("could not find class$ field in java interface type %qT",
6855 return error_mark_node;
6857 iface_ref = build_address (iface_ref);
6858 iface_ref = convert (build_pointer_type (iface), iface_ref);
6860 /* Determine the itable index of FN. */
6862 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
6864 if (!DECL_VIRTUAL_P (method))
6870 idx = build_int_cst (NULL_TREE, i);
6872 lookup_fn = build1 (ADDR_EXPR,
6873 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
6874 java_iface_lookup_fn);
6875 return build_call_nary (ptr_type_node, lookup_fn,
6876 3, klass_ref, iface_ref, idx);
6879 /* Returns the value to use for the in-charge parameter when making a
6880 call to a function with the indicated NAME.
6882 FIXME:Can't we find a neater way to do this mapping? */
6885 in_charge_arg_for_name (tree name)
6887 if (name == base_ctor_identifier
6888 || name == base_dtor_identifier)
6889 return integer_zero_node;
6890 else if (name == complete_ctor_identifier)
6891 return integer_one_node;
6892 else if (name == complete_dtor_identifier)
6893 return integer_two_node;
6894 else if (name == deleting_dtor_identifier)
6895 return integer_three_node;
6897 /* This function should only be called with one of the names listed
6903 /* Build a call to a constructor, destructor, or an assignment
6904 operator for INSTANCE, an expression with class type. NAME
6905 indicates the special member function to call; *ARGS are the
6906 arguments. ARGS may be NULL. This may change ARGS. BINFO
6907 indicates the base of INSTANCE that is to be passed as the `this'
6908 parameter to the member function called.
6910 FLAGS are the LOOKUP_* flags to use when processing the call.
6912 If NAME indicates a complete object constructor, INSTANCE may be
6913 NULL_TREE. In this case, the caller will call build_cplus_new to
6914 store the newly constructed object into a VAR_DECL. */
6917 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6918 tree binfo, int flags, tsubst_flags_t complain)
6921 /* The type of the subobject to be constructed or destroyed. */
6923 VEC(tree,gc) *allocated = NULL;
6926 gcc_assert (name == complete_ctor_identifier
6927 || name == base_ctor_identifier
6928 || name == complete_dtor_identifier
6929 || name == base_dtor_identifier
6930 || name == deleting_dtor_identifier
6931 || name == ansi_assopname (NOP_EXPR));
6934 /* Resolve the name. */
6935 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
6936 return error_mark_node;
6938 binfo = TYPE_BINFO (binfo);
6941 gcc_assert (binfo != NULL_TREE);
6943 class_type = BINFO_TYPE (binfo);
6945 /* Handle the special case where INSTANCE is NULL_TREE. */
6946 if (name == complete_ctor_identifier && !instance)
6948 instance = build_int_cst (build_pointer_type (class_type), 0);
6949 instance = build1 (INDIRECT_REF, class_type, instance);
6953 if (name == complete_dtor_identifier
6954 || name == base_dtor_identifier
6955 || name == deleting_dtor_identifier)
6956 gcc_assert (args == NULL || VEC_empty (tree, *args));
6958 /* Convert to the base class, if necessary. */
6959 if (!same_type_ignoring_top_level_qualifiers_p
6960 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6962 if (name != ansi_assopname (NOP_EXPR))
6963 /* For constructors and destructors, either the base is
6964 non-virtual, or it is virtual but we are doing the
6965 conversion from a constructor or destructor for the
6966 complete object. In either case, we can convert
6968 instance = convert_to_base_statically (instance, binfo);
6970 /* However, for assignment operators, we must convert
6971 dynamically if the base is virtual. */
6972 instance = build_base_path (PLUS_EXPR, instance,
6973 binfo, /*nonnull=*/1, complain);
6977 gcc_assert (instance != NULL_TREE);
6979 fns = lookup_fnfields (binfo, name, 1);
6981 /* When making a call to a constructor or destructor for a subobject
6982 that uses virtual base classes, pass down a pointer to a VTT for
6984 if ((name == base_ctor_identifier
6985 || name == base_dtor_identifier)
6986 && CLASSTYPE_VBASECLASSES (class_type))
6991 /* If the current function is a complete object constructor
6992 or destructor, then we fetch the VTT directly.
6993 Otherwise, we look it up using the VTT we were given. */
6994 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6995 vtt = decay_conversion (vtt);
6996 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6997 build2 (EQ_EXPR, boolean_type_node,
6998 current_in_charge_parm, integer_zero_node),
7001 if (BINFO_SUBVTT_INDEX (binfo))
7002 sub_vtt = fold_build_pointer_plus (vtt, BINFO_SUBVTT_INDEX (binfo));
7008 allocated = make_tree_vector ();
7012 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
7015 ret = build_new_method_call (instance, fns, args,
7016 TYPE_BINFO (BINFO_TYPE (binfo)),
7020 if (allocated != NULL)
7021 release_tree_vector (allocated);
7026 /* Return the NAME, as a C string. The NAME indicates a function that
7027 is a member of TYPE. *FREE_P is set to true if the caller must
7028 free the memory returned.
7030 Rather than go through all of this, we should simply set the names
7031 of constructors and destructors appropriately, and dispense with
7032 ctor_identifier, dtor_identifier, etc. */
7035 name_as_c_string (tree name, tree type, bool *free_p)
7039 /* Assume that we will not allocate memory. */
7041 /* Constructors and destructors are special. */
7042 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7045 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
7046 /* For a destructor, add the '~'. */
7047 if (name == complete_dtor_identifier
7048 || name == base_dtor_identifier
7049 || name == deleting_dtor_identifier)
7051 pretty_name = concat ("~", pretty_name, NULL);
7052 /* Remember that we need to free the memory allocated. */
7056 else if (IDENTIFIER_TYPENAME_P (name))
7058 pretty_name = concat ("operator ",
7059 type_as_string_translate (TREE_TYPE (name),
7060 TFF_PLAIN_IDENTIFIER),
7062 /* Remember that we need to free the memory allocated. */
7066 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
7071 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
7072 be set, upon return, to the function called. ARGS may be NULL.
7073 This may change ARGS. */
7076 build_new_method_call_1 (tree instance, tree fns, VEC(tree,gc) **args,
7077 tree conversion_path, int flags,
7078 tree *fn_p, tsubst_flags_t complain)
7080 struct z_candidate *candidates = 0, *cand;
7081 tree explicit_targs = NULL_TREE;
7082 tree basetype = NULL_TREE;
7085 tree first_mem_arg = NULL_TREE;
7088 bool skip_first_for_error;
7089 VEC(tree,gc) *user_args;
7092 int template_only = 0;
7096 VEC(tree,gc) *orig_args = NULL;
7099 gcc_assert (instance != NULL_TREE);
7101 /* We don't know what function we're going to call, yet. */
7105 if (error_operand_p (instance)
7106 || !fns || error_operand_p (fns))
7107 return error_mark_node;
7109 if (!BASELINK_P (fns))
7111 if (complain & tf_error)
7112 error ("call to non-function %qD", fns);
7113 return error_mark_node;
7116 orig_instance = instance;
7119 /* Dismantle the baselink to collect all the information we need. */
7120 if (!conversion_path)
7121 conversion_path = BASELINK_BINFO (fns);
7122 access_binfo = BASELINK_ACCESS_BINFO (fns);
7123 optype = BASELINK_OPTYPE (fns);
7124 fns = BASELINK_FUNCTIONS (fns);
7125 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7127 explicit_targs = TREE_OPERAND (fns, 1);
7128 fns = TREE_OPERAND (fns, 0);
7131 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
7132 || TREE_CODE (fns) == TEMPLATE_DECL
7133 || TREE_CODE (fns) == OVERLOAD);
7134 fn = get_first_fn (fns);
7135 name = DECL_NAME (fn);
7137 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
7138 gcc_assert (CLASS_TYPE_P (basetype));
7140 if (processing_template_decl)
7142 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
7143 instance = build_non_dependent_expr (instance);
7145 make_args_non_dependent (*args);
7148 user_args = args == NULL ? NULL : *args;
7149 /* Under DR 147 A::A() is an invalid constructor call,
7150 not a functional cast. */
7151 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
7153 if (! (complain & tf_error))
7154 return error_mark_node;
7156 permerror (input_location,
7157 "cannot call constructor %<%T::%D%> directly",
7159 permerror (input_location, " for a function-style cast, remove the "
7160 "redundant %<::%D%>", name);
7161 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
7166 /* Figure out whether to skip the first argument for the error
7167 message we will display to users if an error occurs. We don't
7168 want to display any compiler-generated arguments. The "this"
7169 pointer hasn't been added yet. However, we must remove the VTT
7170 pointer if this is a call to a base-class constructor or
7172 skip_first_for_error = false;
7173 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7175 /* Callers should explicitly indicate whether they want to construct
7176 the complete object or just the part without virtual bases. */
7177 gcc_assert (name != ctor_identifier);
7178 /* Similarly for destructors. */
7179 gcc_assert (name != dtor_identifier);
7180 /* Remove the VTT pointer, if present. */
7181 if ((name == base_ctor_identifier || name == base_dtor_identifier)
7182 && CLASSTYPE_VBASECLASSES (basetype))
7183 skip_first_for_error = true;
7186 /* Process the argument list. */
7187 if (args != NULL && *args != NULL)
7189 *args = resolve_args (*args, complain);
7191 return error_mark_node;
7194 instance_ptr = build_this (instance);
7196 /* It's OK to call destructors and constructors on cv-qualified objects.
7197 Therefore, convert the INSTANCE_PTR to the unqualified type, if
7199 if (DECL_DESTRUCTOR_P (fn)
7200 || DECL_CONSTRUCTOR_P (fn))
7202 tree type = build_pointer_type (basetype);
7203 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
7204 instance_ptr = build_nop (type, instance_ptr);
7206 if (DECL_DESTRUCTOR_P (fn))
7207 name = complete_dtor_identifier;
7209 first_mem_arg = instance_ptr;
7211 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7212 p = conversion_obstack_alloc (0);
7214 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
7215 initializer, not T({ }). */
7216 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
7217 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
7218 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0)))
7220 tree init_list = VEC_index (tree, *args, 0);
7221 tree init = NULL_TREE;
7223 gcc_assert (VEC_length (tree, *args) == 1
7224 && !(flags & LOOKUP_ONLYCONVERTING));
7226 /* If the initializer list has no elements and T is a class type with
7227 a default constructor, the object is value-initialized. Handle
7228 this here so we don't need to handle it wherever we use
7229 build_special_member_call. */
7230 if (CONSTRUCTOR_NELTS (init_list) == 0
7231 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
7232 && !processing_template_decl)
7233 init = build_value_init (basetype, complain);
7235 /* If BASETYPE is an aggregate, we need to do aggregate
7237 else if (CP_AGGREGATE_TYPE_P (basetype))
7238 init = digest_init (basetype, init_list, complain);
7243 if (integer_zerop (instance_ptr))
7244 return get_target_expr_sfinae (init, complain);
7245 ob = build_fold_indirect_ref (instance_ptr);
7246 init = build2 (INIT_EXPR, TREE_TYPE (ob), ob, init);
7247 TREE_SIDE_EFFECTS (init) = true;
7251 /* Otherwise go ahead with overload resolution. */
7252 add_list_candidates (fns, first_mem_arg, init_list,
7253 basetype, explicit_targs, template_only,
7254 conversion_path, access_binfo, flags, &candidates);
7258 add_candidates (fns, first_mem_arg, user_args, optype,
7259 explicit_targs, template_only, conversion_path,
7260 access_binfo, flags, &candidates);
7262 any_viable_p = false;
7263 candidates = splice_viable (candidates, pedantic, &any_viable_p);
7267 if (complain & tf_error)
7269 if (!COMPLETE_OR_OPEN_TYPE_P (basetype))
7270 cxx_incomplete_type_error (instance_ptr, basetype);
7272 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
7273 basetype, optype, build_tree_list_vec (user_args),
7274 TREE_TYPE (TREE_TYPE (instance_ptr)));
7281 pretty_name = name_as_c_string (name, basetype, &free_p);
7282 arglist = build_tree_list_vec (user_args);
7283 if (skip_first_for_error)
7284 arglist = TREE_CHAIN (arglist);
7285 error ("no matching function for call to %<%T::%s(%A)%#V%>",
7286 basetype, pretty_name, arglist,
7287 TREE_TYPE (TREE_TYPE (instance_ptr)));
7291 print_z_candidates (location_of (name), candidates);
7293 call = error_mark_node;
7297 cand = tourney (candidates);
7304 if (complain & tf_error)
7306 pretty_name = name_as_c_string (name, basetype, &free_p);
7307 arglist = build_tree_list_vec (user_args);
7308 if (skip_first_for_error)
7309 arglist = TREE_CHAIN (arglist);
7310 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
7312 print_z_candidates (location_of (name), candidates);
7316 call = error_mark_node;
7322 if (!(flags & LOOKUP_NONVIRTUAL)
7323 && DECL_PURE_VIRTUAL_P (fn)
7324 && instance == current_class_ref
7325 && (DECL_CONSTRUCTOR_P (current_function_decl)
7326 || DECL_DESTRUCTOR_P (current_function_decl))
7327 && (complain & tf_warning))
7328 /* This is not an error, it is runtime undefined
7330 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
7331 "pure virtual %q#D called from constructor"
7332 : "pure virtual %q#D called from destructor"),
7335 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
7336 && is_dummy_object (instance_ptr))
7338 if (complain & tf_error)
7339 error ("cannot call member function %qD without object",
7341 call = error_mark_node;
7345 /* Optimize away vtable lookup if we know that this function
7346 can't be overridden. */
7347 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
7348 && (resolves_to_fixed_type_p (instance, 0)
7349 || DECL_FINAL_P (fn) || CLASSTYPE_FINAL (basetype)))
7350 flags |= LOOKUP_NONVIRTUAL;
7352 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
7353 /* Now we know what function is being called. */
7356 /* Build the actual CALL_EXPR. */
7357 call = build_over_call (cand, flags, complain);
7358 /* In an expression of the form `a->f()' where `f' turns
7359 out to be a static member function, `a' is
7360 none-the-less evaluated. */
7361 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
7362 && !is_dummy_object (instance_ptr)
7363 && TREE_SIDE_EFFECTS (instance_ptr))
7364 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
7365 instance_ptr, call);
7366 else if (call != error_mark_node
7367 && DECL_DESTRUCTOR_P (cand->fn)
7368 && !VOID_TYPE_P (TREE_TYPE (call)))
7369 /* An explicit call of the form "x->~X()" has type
7370 "void". However, on platforms where destructors
7371 return "this" (i.e., those where
7372 targetm.cxx.cdtor_returns_this is true), such calls
7373 will appear to have a return value of pointer type
7374 to the low-level call machinery. We do not want to
7375 change the low-level machinery, since we want to be
7376 able to optimize "delete f()" on such platforms as
7377 "operator delete(~X(f()))" (rather than generating
7378 "t = f(), ~X(t), operator delete (t)"). */
7379 call = build_nop (void_type_node, call);
7384 if (processing_template_decl && call != error_mark_node)
7386 bool cast_to_void = false;
7388 if (TREE_CODE (call) == COMPOUND_EXPR)
7389 call = TREE_OPERAND (call, 1);
7390 else if (TREE_CODE (call) == NOP_EXPR)
7392 cast_to_void = true;
7393 call = TREE_OPERAND (call, 0);
7395 if (TREE_CODE (call) == INDIRECT_REF)
7396 call = TREE_OPERAND (call, 0);
7397 call = (build_min_non_dep_call_vec
7399 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
7400 orig_instance, orig_fns, NULL_TREE),
7402 call = convert_from_reference (call);
7404 call = build_nop (void_type_node, call);
7407 /* Free all the conversions we allocated. */
7408 obstack_free (&conversion_obstack, p);
7410 if (orig_args != NULL)
7411 release_tree_vector (orig_args);
7416 /* Wrapper for above. */
7419 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
7420 tree conversion_path, int flags,
7421 tree *fn_p, tsubst_flags_t complain)
7424 bool subtime = timevar_cond_start (TV_OVERLOAD);
7425 ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags,
7427 timevar_cond_stop (TV_OVERLOAD, subtime);
7431 /* Returns true iff standard conversion sequence ICS1 is a proper
7432 subsequence of ICS2. */
7435 is_subseq (conversion *ics1, conversion *ics2)
7437 /* We can assume that a conversion of the same code
7438 between the same types indicates a subsequence since we only get
7439 here if the types we are converting from are the same. */
7441 while (ics1->kind == ck_rvalue
7442 || ics1->kind == ck_lvalue)
7443 ics1 = ics1->u.next;
7447 while (ics2->kind == ck_rvalue
7448 || ics2->kind == ck_lvalue)
7449 ics2 = ics2->u.next;
7451 if (ics2->kind == ck_user
7452 || ics2->kind == ck_ambig
7453 || ics2->kind == ck_aggr
7454 || ics2->kind == ck_list
7455 || ics2->kind == ck_identity)
7456 /* At this point, ICS1 cannot be a proper subsequence of
7457 ICS2. We can get a USER_CONV when we are comparing the
7458 second standard conversion sequence of two user conversion
7462 ics2 = ics2->u.next;
7464 if (ics2->kind == ics1->kind
7465 && same_type_p (ics2->type, ics1->type)
7466 && same_type_p (ics2->u.next->type,
7467 ics1->u.next->type))
7472 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
7473 be any _TYPE nodes. */
7476 is_properly_derived_from (tree derived, tree base)
7478 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
7481 /* We only allow proper derivation here. The DERIVED_FROM_P macro
7482 considers every class derived from itself. */
7483 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
7484 && DERIVED_FROM_P (base, derived));
7487 /* We build the ICS for an implicit object parameter as a pointer
7488 conversion sequence. However, such a sequence should be compared
7489 as if it were a reference conversion sequence. If ICS is the
7490 implicit conversion sequence for an implicit object parameter,
7491 modify it accordingly. */
7494 maybe_handle_implicit_object (conversion **ics)
7498 /* [over.match.funcs]
7500 For non-static member functions, the type of the
7501 implicit object parameter is "reference to cv X"
7502 where X is the class of which the function is a
7503 member and cv is the cv-qualification on the member
7504 function declaration. */
7505 conversion *t = *ics;
7506 tree reference_type;
7508 /* The `this' parameter is a pointer to a class type. Make the
7509 implicit conversion talk about a reference to that same class
7511 reference_type = TREE_TYPE (t->type);
7512 reference_type = build_reference_type (reference_type);
7514 if (t->kind == ck_qual)
7516 if (t->kind == ck_ptr)
7518 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
7519 t = direct_reference_binding (reference_type, t);
7521 t->rvaluedness_matches_p = 0;
7526 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
7527 and return the initial reference binding conversion. Otherwise,
7528 leave *ICS unchanged and return NULL. */
7531 maybe_handle_ref_bind (conversion **ics)
7533 if ((*ics)->kind == ck_ref_bind)
7535 conversion *old_ics = *ics;
7536 *ics = old_ics->u.next;
7537 (*ics)->user_conv_p = old_ics->user_conv_p;
7544 /* Compare two implicit conversion sequences according to the rules set out in
7545 [over.ics.rank]. Return values:
7547 1: ics1 is better than ics2
7548 -1: ics2 is better than ics1
7549 0: ics1 and ics2 are indistinguishable */
7552 compare_ics (conversion *ics1, conversion *ics2)
7558 tree deref_from_type1 = NULL_TREE;
7559 tree deref_from_type2 = NULL_TREE;
7560 tree deref_to_type1 = NULL_TREE;
7561 tree deref_to_type2 = NULL_TREE;
7562 conversion_rank rank1, rank2;
7564 /* REF_BINDING is nonzero if the result of the conversion sequence
7565 is a reference type. In that case REF_CONV is the reference
7566 binding conversion. */
7567 conversion *ref_conv1;
7568 conversion *ref_conv2;
7570 /* Handle implicit object parameters. */
7571 maybe_handle_implicit_object (&ics1);
7572 maybe_handle_implicit_object (&ics2);
7574 /* Handle reference parameters. */
7575 ref_conv1 = maybe_handle_ref_bind (&ics1);
7576 ref_conv2 = maybe_handle_ref_bind (&ics2);
7578 /* List-initialization sequence L1 is a better conversion sequence than
7579 list-initialization sequence L2 if L1 converts to
7580 std::initializer_list<X> for some X and L2 does not. */
7581 if (ics1->kind == ck_list && ics2->kind != ck_list)
7583 if (ics2->kind == ck_list && ics1->kind != ck_list)
7588 When comparing the basic forms of implicit conversion sequences (as
7589 defined in _over.best.ics_)
7591 --a standard conversion sequence (_over.ics.scs_) is a better
7592 conversion sequence than a user-defined conversion sequence
7593 or an ellipsis conversion sequence, and
7595 --a user-defined conversion sequence (_over.ics.user_) is a
7596 better conversion sequence than an ellipsis conversion sequence
7597 (_over.ics.ellipsis_). */
7598 rank1 = CONVERSION_RANK (ics1);
7599 rank2 = CONVERSION_RANK (ics2);
7603 else if (rank1 < rank2)
7606 if (rank1 == cr_bad)
7608 /* Both ICS are bad. We try to make a decision based on what would
7609 have happened if they'd been good. This is not an extension,
7610 we'll still give an error when we build up the call; this just
7611 helps us give a more helpful error message. */
7612 rank1 = BAD_CONVERSION_RANK (ics1);
7613 rank2 = BAD_CONVERSION_RANK (ics2);
7617 else if (rank1 < rank2)
7620 /* We couldn't make up our minds; try to figure it out below. */
7623 if (ics1->ellipsis_p)
7624 /* Both conversions are ellipsis conversions. */
7627 /* User-defined conversion sequence U1 is a better conversion sequence
7628 than another user-defined conversion sequence U2 if they contain the
7629 same user-defined conversion operator or constructor and if the sec-
7630 ond standard conversion sequence of U1 is better than the second
7631 standard conversion sequence of U2. */
7633 /* Handle list-conversion with the same code even though it isn't always
7634 ranked as a user-defined conversion and it doesn't have a second
7635 standard conversion sequence; it will still have the desired effect.
7636 Specifically, we need to do the reference binding comparison at the
7637 end of this function. */
7639 if (ics1->user_conv_p || ics1->kind == ck_list)
7644 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
7645 if (t1->kind == ck_ambig || t1->kind == ck_aggr
7646 || t1->kind == ck_list)
7648 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
7649 if (t2->kind == ck_ambig || t2->kind == ck_aggr
7650 || t2->kind == ck_list)
7653 if (t1->kind != t2->kind)
7655 else if (t1->kind == ck_user)
7657 if (t1->cand->fn != t2->cand->fn)
7662 /* For ambiguous or aggregate conversions, use the target type as
7663 a proxy for the conversion function. */
7664 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
7668 /* We can just fall through here, after setting up
7669 FROM_TYPE1 and FROM_TYPE2. */
7670 from_type1 = t1->type;
7671 from_type2 = t2->type;
7678 /* We're dealing with two standard conversion sequences.
7682 Standard conversion sequence S1 is a better conversion
7683 sequence than standard conversion sequence S2 if
7685 --S1 is a proper subsequence of S2 (comparing the conversion
7686 sequences in the canonical form defined by _over.ics.scs_,
7687 excluding any Lvalue Transformation; the identity
7688 conversion sequence is considered to be a subsequence of
7689 any non-identity conversion sequence */
7692 while (t1->kind != ck_identity)
7694 from_type1 = t1->type;
7697 while (t2->kind != ck_identity)
7699 from_type2 = t2->type;
7702 /* One sequence can only be a subsequence of the other if they start with
7703 the same type. They can start with different types when comparing the
7704 second standard conversion sequence in two user-defined conversion
7706 if (same_type_p (from_type1, from_type2))
7708 if (is_subseq (ics1, ics2))
7710 if (is_subseq (ics2, ics1))
7718 --the rank of S1 is better than the rank of S2 (by the rules
7721 Standard conversion sequences are ordered by their ranks: an Exact
7722 Match is a better conversion than a Promotion, which is a better
7723 conversion than a Conversion.
7725 Two conversion sequences with the same rank are indistinguishable
7726 unless one of the following rules applies:
7728 --A conversion that does not a convert a pointer, pointer to member,
7729 or std::nullptr_t to bool is better than one that does.
7731 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
7732 so that we do not have to check it explicitly. */
7733 if (ics1->rank < ics2->rank)
7735 else if (ics2->rank < ics1->rank)
7738 to_type1 = ics1->type;
7739 to_type2 = ics2->type;
7741 /* A conversion from scalar arithmetic type to complex is worse than a
7742 conversion between scalar arithmetic types. */
7743 if (same_type_p (from_type1, from_type2)
7744 && ARITHMETIC_TYPE_P (from_type1)
7745 && ARITHMETIC_TYPE_P (to_type1)
7746 && ARITHMETIC_TYPE_P (to_type2)
7747 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
7748 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
7750 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
7756 if (TYPE_PTR_P (from_type1)
7757 && TYPE_PTR_P (from_type2)
7758 && TYPE_PTR_P (to_type1)
7759 && TYPE_PTR_P (to_type2))
7761 deref_from_type1 = TREE_TYPE (from_type1);
7762 deref_from_type2 = TREE_TYPE (from_type2);
7763 deref_to_type1 = TREE_TYPE (to_type1);
7764 deref_to_type2 = TREE_TYPE (to_type2);
7766 /* The rules for pointers to members A::* are just like the rules
7767 for pointers A*, except opposite: if B is derived from A then
7768 A::* converts to B::*, not vice versa. For that reason, we
7769 switch the from_ and to_ variables here. */
7770 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
7771 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
7772 || (TYPE_PTRMEMFUNC_P (from_type1)
7773 && TYPE_PTRMEMFUNC_P (from_type2)
7774 && TYPE_PTRMEMFUNC_P (to_type1)
7775 && TYPE_PTRMEMFUNC_P (to_type2)))
7777 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
7778 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
7779 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
7780 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
7783 if (deref_from_type1 != NULL_TREE
7784 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
7785 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
7787 /* This was one of the pointer or pointer-like conversions.
7791 --If class B is derived directly or indirectly from class A,
7792 conversion of B* to A* is better than conversion of B* to
7793 void*, and conversion of A* to void* is better than
7794 conversion of B* to void*. */
7795 if (TREE_CODE (deref_to_type1) == VOID_TYPE
7796 && TREE_CODE (deref_to_type2) == VOID_TYPE)
7798 if (is_properly_derived_from (deref_from_type1,
7801 else if (is_properly_derived_from (deref_from_type2,
7805 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
7806 || TREE_CODE (deref_to_type2) == VOID_TYPE)
7808 if (same_type_p (deref_from_type1, deref_from_type2))
7810 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
7812 if (is_properly_derived_from (deref_from_type1,
7816 /* We know that DEREF_TO_TYPE1 is `void' here. */
7817 else if (is_properly_derived_from (deref_from_type1,
7822 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
7823 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
7827 --If class B is derived directly or indirectly from class A
7828 and class C is derived directly or indirectly from B,
7830 --conversion of C* to B* is better than conversion of C* to
7833 --conversion of B* to A* is better than conversion of C* to
7835 if (same_type_p (deref_from_type1, deref_from_type2))
7837 if (is_properly_derived_from (deref_to_type1,
7840 else if (is_properly_derived_from (deref_to_type2,
7844 else if (same_type_p (deref_to_type1, deref_to_type2))
7846 if (is_properly_derived_from (deref_from_type2,
7849 else if (is_properly_derived_from (deref_from_type1,
7855 else if (CLASS_TYPE_P (non_reference (from_type1))
7856 && same_type_p (from_type1, from_type2))
7858 tree from = non_reference (from_type1);
7862 --binding of an expression of type C to a reference of type
7863 B& is better than binding an expression of type C to a
7864 reference of type A&
7866 --conversion of C to B is better than conversion of C to A, */
7867 if (is_properly_derived_from (from, to_type1)
7868 && is_properly_derived_from (from, to_type2))
7870 if (is_properly_derived_from (to_type1, to_type2))
7872 else if (is_properly_derived_from (to_type2, to_type1))
7876 else if (CLASS_TYPE_P (non_reference (to_type1))
7877 && same_type_p (to_type1, to_type2))
7879 tree to = non_reference (to_type1);
7883 --binding of an expression of type B to a reference of type
7884 A& is better than binding an expression of type C to a
7885 reference of type A&,
7887 --conversion of B to A is better than conversion of C to A */
7888 if (is_properly_derived_from (from_type1, to)
7889 && is_properly_derived_from (from_type2, to))
7891 if (is_properly_derived_from (from_type2, from_type1))
7893 else if (is_properly_derived_from (from_type1, from_type2))
7900 --S1 and S2 differ only in their qualification conversion and yield
7901 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
7902 qualification signature of type T1 is a proper subset of the cv-
7903 qualification signature of type T2 */
7904 if (ics1->kind == ck_qual
7905 && ics2->kind == ck_qual
7906 && same_type_p (from_type1, from_type2))
7908 int result = comp_cv_qual_signature (to_type1, to_type2);
7915 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
7916 to an implicit object parameter, and either S1 binds an lvalue reference
7917 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
7918 reference to an rvalue and S2 binds an lvalue reference
7919 (C++0x draft standard, 13.3.3.2)
7921 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
7922 types to which the references refer are the same type except for
7923 top-level cv-qualifiers, and the type to which the reference
7924 initialized by S2 refers is more cv-qualified than the type to
7925 which the reference initialized by S1 refers.
7927 DR 1328 [over.match.best]: the context is an initialization by
7928 conversion function for direct reference binding (13.3.1.6) of a
7929 reference to function type, the return type of F1 is the same kind of
7930 reference (i.e. lvalue or rvalue) as the reference being initialized,
7931 and the return type of F2 is not. */
7933 if (ref_conv1 && ref_conv2)
7935 if (!ref_conv1->this_p && !ref_conv2->this_p
7936 && (ref_conv1->rvaluedness_matches_p
7937 != ref_conv2->rvaluedness_matches_p)
7938 && (same_type_p (ref_conv1->type, ref_conv2->type)
7939 || (TYPE_REF_IS_RVALUE (ref_conv1->type)
7940 != TYPE_REF_IS_RVALUE (ref_conv2->type))))
7942 return (ref_conv1->rvaluedness_matches_p
7943 - ref_conv2->rvaluedness_matches_p);
7946 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
7947 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
7948 TREE_TYPE (ref_conv1->type));
7951 /* Neither conversion sequence is better than the other. */
7955 /* The source type for this standard conversion sequence. */
7958 source_type (conversion *t)
7960 for (;; t = t->u.next)
7962 if (t->kind == ck_user
7963 || t->kind == ck_ambig
7964 || t->kind == ck_identity)
7970 /* Note a warning about preferring WINNER to LOSER. We do this by storing
7971 a pointer to LOSER and re-running joust to produce the warning if WINNER
7972 is actually used. */
7975 add_warning (struct z_candidate *winner, struct z_candidate *loser)
7977 candidate_warning *cw = (candidate_warning *)
7978 conversion_obstack_alloc (sizeof (candidate_warning));
7980 cw->next = winner->warnings;
7981 winner->warnings = cw;
7984 /* Compare two candidates for overloading as described in
7985 [over.match.best]. Return values:
7987 1: cand1 is better than cand2
7988 -1: cand2 is better than cand1
7989 0: cand1 and cand2 are indistinguishable */
7992 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7995 int off1 = 0, off2 = 0;
7999 /* Candidates that involve bad conversions are always worse than those
8001 if (cand1->viable > cand2->viable)
8003 if (cand1->viable < cand2->viable)
8006 /* If we have two pseudo-candidates for conversions to the same type,
8007 or two candidates for the same function, arbitrarily pick one. */
8008 if (cand1->fn == cand2->fn
8009 && (IS_TYPE_OR_DECL_P (cand1->fn)))
8012 /* a viable function F1
8013 is defined to be a better function than another viable function F2 if
8014 for all arguments i, ICSi(F1) is not a worse conversion sequence than
8015 ICSi(F2), and then */
8017 /* for some argument j, ICSj(F1) is a better conversion sequence than
8020 /* For comparing static and non-static member functions, we ignore
8021 the implicit object parameter of the non-static function. The
8022 standard says to pretend that the static function has an object
8023 parm, but that won't work with operator overloading. */
8024 len = cand1->num_convs;
8025 if (len != cand2->num_convs)
8027 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
8028 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
8030 gcc_assert (static_1 != static_2);
8041 for (i = 0; i < len; ++i)
8043 conversion *t1 = cand1->convs[i + off1];
8044 conversion *t2 = cand2->convs[i + off2];
8045 int comp = compare_ics (t1, t2);
8050 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
8051 == cr_std + cr_promotion)
8052 && t1->kind == ck_std
8053 && t2->kind == ck_std
8054 && TREE_CODE (t1->type) == INTEGER_TYPE
8055 && TREE_CODE (t2->type) == INTEGER_TYPE
8056 && (TYPE_PRECISION (t1->type)
8057 == TYPE_PRECISION (t2->type))
8058 && (TYPE_UNSIGNED (t1->u.next->type)
8059 || (TREE_CODE (t1->u.next->type)
8062 tree type = t1->u.next->type;
8064 struct z_candidate *w, *l;
8066 type1 = t1->type, type2 = t2->type,
8067 w = cand1, l = cand2;
8069 type1 = t2->type, type2 = t1->type,
8070 w = cand2, l = cand1;
8074 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
8075 type, type1, type2);
8076 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
8082 if (winner && comp != winner)
8091 /* warn about confusing overload resolution for user-defined conversions,
8092 either between a constructor and a conversion op, or between two
8094 if (winner && warn_conversion && cand1->second_conv
8095 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
8096 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
8098 struct z_candidate *w, *l;
8099 bool give_warning = false;
8102 w = cand1, l = cand2;
8104 w = cand2, l = cand1;
8106 /* We don't want to complain about `X::operator T1 ()'
8107 beating `X::operator T2 () const', when T2 is a no less
8108 cv-qualified version of T1. */
8109 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
8110 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
8112 tree t = TREE_TYPE (TREE_TYPE (l->fn));
8113 tree f = TREE_TYPE (TREE_TYPE (w->fn));
8115 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
8120 if (!comp_ptr_ttypes (t, f))
8121 give_warning = true;
8124 give_warning = true;
8130 tree source = source_type (w->convs[0]);
8131 if (! DECL_CONSTRUCTOR_P (w->fn))
8132 source = TREE_TYPE (source);
8133 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
8134 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
8135 source, w->second_conv->type))
8137 inform (input_location, " because conversion sequence for the argument is better");
8147 /* DR 495 moved this tiebreaker above the template ones. */
8149 the context is an initialization by user-defined conversion (see
8150 _dcl.init_ and _over.match.user_) and the standard conversion
8151 sequence from the return type of F1 to the destination type (i.e.,
8152 the type of the entity being initialized) is a better conversion
8153 sequence than the standard conversion sequence from the return type
8154 of F2 to the destination type. */
8156 if (cand1->second_conv)
8158 winner = compare_ics (cand1->second_conv, cand2->second_conv);
8164 F1 is a non-template function and F2 is a template function
8167 if (!cand1->template_decl && cand2->template_decl)
8169 else if (cand1->template_decl && !cand2->template_decl)
8173 F1 and F2 are template functions and the function template for F1 is
8174 more specialized than the template for F2 according to the partial
8177 if (cand1->template_decl && cand2->template_decl)
8179 winner = more_specialized_fn
8180 (TI_TEMPLATE (cand1->template_decl),
8181 TI_TEMPLATE (cand2->template_decl),
8182 /* [temp.func.order]: The presence of unused ellipsis and default
8183 arguments has no effect on the partial ordering of function
8184 templates. add_function_candidate() will not have
8185 counted the "this" argument for constructors. */
8186 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
8191 /* Check whether we can discard a builtin candidate, either because we
8192 have two identical ones or matching builtin and non-builtin candidates.
8194 (Pedantically in the latter case the builtin which matched the user
8195 function should not be added to the overload set, but we spot it here.
8198 ... the builtin candidates include ...
8199 - do not have the same parameter type list as any non-template
8200 non-member candidate. */
8202 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
8203 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
8205 for (i = 0; i < len; ++i)
8206 if (!same_type_p (cand1->convs[i]->type,
8207 cand2->convs[i]->type))
8209 if (i == cand1->num_convs)
8211 if (cand1->fn == cand2->fn)
8212 /* Two built-in candidates; arbitrarily pick one. */
8214 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
8215 /* cand1 is built-in; prefer cand2. */
8218 /* cand2 is built-in; prefer cand1. */
8223 /* If the two function declarations represent the same function (this can
8224 happen with declarations in multiple scopes and arg-dependent lookup),
8225 arbitrarily choose one. But first make sure the default args we're
8227 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
8228 && equal_functions (cand1->fn, cand2->fn))
8230 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
8231 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
8233 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
8235 for (i = 0; i < len; ++i)
8237 /* Don't crash if the fn is variadic. */
8240 parms1 = TREE_CHAIN (parms1);
8241 parms2 = TREE_CHAIN (parms2);
8245 parms1 = TREE_CHAIN (parms1);
8247 parms2 = TREE_CHAIN (parms2);
8251 if (!cp_tree_equal (TREE_PURPOSE (parms1),
8252 TREE_PURPOSE (parms2)))
8256 permerror (input_location, "default argument mismatch in "
8257 "overload resolution");
8258 inform (input_location,
8259 " candidate 1: %q+#F", cand1->fn);
8260 inform (input_location,
8261 " candidate 2: %q+#F", cand2->fn);
8264 add_warning (cand1, cand2);
8267 parms1 = TREE_CHAIN (parms1);
8268 parms2 = TREE_CHAIN (parms2);
8276 /* Extension: If the worst conversion for one candidate is worse than the
8277 worst conversion for the other, take the first. */
8280 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
8281 struct z_candidate *w = 0, *l = 0;
8283 for (i = 0; i < len; ++i)
8285 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
8286 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
8287 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
8288 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
8291 winner = 1, w = cand1, l = cand2;
8293 winner = -1, w = cand2, l = cand1;
8296 /* Don't choose a deleted function over ambiguity. */
8297 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
8301 pedwarn (input_location, 0,
8302 "ISO C++ says that these are ambiguous, even "
8303 "though the worst conversion for the first is better than "
8304 "the worst conversion for the second:");
8305 print_z_candidate (_("candidate 1:"), w);
8306 print_z_candidate (_("candidate 2:"), l);
8314 gcc_assert (!winner);
8318 /* Given a list of candidates for overloading, find the best one, if any.
8319 This algorithm has a worst case of O(2n) (winner is last), and a best
8320 case of O(n/2) (totally ambiguous); much better than a sorting
8323 static struct z_candidate *
8324 tourney (struct z_candidate *candidates)
8326 struct z_candidate *champ = candidates, *challenger;
8328 int champ_compared_to_predecessor = 0;
8330 /* Walk through the list once, comparing each current champ to the next
8331 candidate, knocking out a candidate or two with each comparison. */
8333 for (challenger = champ->next; challenger; )
8335 fate = joust (champ, challenger, 0);
8337 challenger = challenger->next;
8342 champ = challenger->next;
8345 champ_compared_to_predecessor = 0;
8350 champ_compared_to_predecessor = 1;
8353 challenger = champ->next;
8357 /* Make sure the champ is better than all the candidates it hasn't yet
8358 been compared to. */
8360 for (challenger = candidates;
8362 && !(champ_compared_to_predecessor && challenger->next == champ);
8363 challenger = challenger->next)
8365 fate = joust (champ, challenger, 0);
8373 /* Returns nonzero if things of type FROM can be converted to TO. */
8376 can_convert (tree to, tree from)
8378 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
8381 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
8384 can_convert_arg (tree to, tree from, tree arg, int flags)
8390 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8391 p = conversion_obstack_alloc (0);
8393 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8395 ok_p = (t && !t->bad_p);
8397 /* Free all the conversions we allocated. */
8398 obstack_free (&conversion_obstack, p);
8403 /* Like can_convert_arg, but allows dubious conversions as well. */
8406 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
8411 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8412 p = conversion_obstack_alloc (0);
8413 /* Try to perform the conversion. */
8414 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8416 /* Free all the conversions we allocated. */
8417 obstack_free (&conversion_obstack, p);
8422 /* Convert EXPR to TYPE. Return the converted expression.
8424 Note that we allow bad conversions here because by the time we get to
8425 this point we are committed to doing the conversion. If we end up
8426 doing a bad conversion, convert_like will complain. */
8429 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
8434 if (error_operand_p (expr))
8435 return error_mark_node;
8437 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8438 p = conversion_obstack_alloc (0);
8440 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8446 if (complain & tf_error)
8448 /* If expr has unknown type, then it is an overloaded function.
8449 Call instantiate_type to get good error messages. */
8450 if (TREE_TYPE (expr) == unknown_type_node)
8451 instantiate_type (type, expr, complain);
8452 else if (invalid_nonstatic_memfn_p (expr, complain))
8453 /* We gave an error. */;
8455 error ("could not convert %qE from %qT to %qT", expr,
8456 TREE_TYPE (expr), type);
8458 expr = error_mark_node;
8460 else if (processing_template_decl && conv->kind != ck_identity)
8462 /* In a template, we are only concerned about determining the
8463 type of non-dependent expressions, so we do not have to
8464 perform the actual conversion. But for initializers, we
8465 need to be able to perform it at instantiation
8466 (or fold_non_dependent_expr) time. */
8467 expr = build1 (IMPLICIT_CONV_EXPR, type, expr);
8468 if (!(flags & LOOKUP_ONLYCONVERTING))
8469 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr) = true;
8472 expr = convert_like (conv, expr, complain);
8474 /* Free all the conversions we allocated. */
8475 obstack_free (&conversion_obstack, p);
8481 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
8483 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
8486 /* Convert EXPR to TYPE (as a direct-initialization) if that is
8487 permitted. If the conversion is valid, the converted expression is
8488 returned. Otherwise, NULL_TREE is returned, except in the case
8489 that TYPE is a class type; in that case, an error is issued. If
8490 C_CAST_P is true, then this direct-initialization is taking
8491 place as part of a static_cast being attempted as part of a C-style
8495 perform_direct_initialization_if_possible (tree type,
8498 tsubst_flags_t complain)
8503 if (type == error_mark_node || error_operand_p (expr))
8504 return error_mark_node;
8507 If the destination type is a (possibly cv-qualified) class type:
8509 -- If the initialization is direct-initialization ...,
8510 constructors are considered. ... If no constructor applies, or
8511 the overload resolution is ambiguous, the initialization is
8513 if (CLASS_TYPE_P (type))
8515 VEC(tree,gc) *args = make_tree_vector_single (expr);
8516 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
8517 &args, type, LOOKUP_NORMAL, complain);
8518 release_tree_vector (args);
8519 return build_cplus_new (type, expr, complain);
8522 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8523 p = conversion_obstack_alloc (0);
8525 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8528 if (!conv || conv->bad_p)
8531 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
8532 /*issue_conversion_warnings=*/false,
8536 /* Free all the conversions we allocated. */
8537 obstack_free (&conversion_obstack, p);
8542 /* When initializing a reference that lasts longer than a full-expression,
8543 this special rule applies:
8547 The temporary to which the reference is bound or the temporary
8548 that is the complete object to which the reference is bound
8549 persists for the lifetime of the reference.
8551 The temporaries created during the evaluation of the expression
8552 initializing the reference, except the temporary to which the
8553 reference is bound, are destroyed at the end of the
8554 full-expression in which they are created.
8556 In that case, we store the converted expression into a new
8557 VAR_DECL in a new scope.
8559 However, we want to be careful not to create temporaries when
8560 they are not required. For example, given:
8563 struct D : public B {};
8567 there is no need to copy the return value from "f"; we can just
8568 extend its lifetime. Similarly, given:
8571 struct T { operator S(); };
8575 we can extend the lifetime of the return value of the conversion
8578 The next several functions are involved in this lifetime extension. */
8580 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
8581 is being bound to a temporary. Create and return a new VAR_DECL
8582 with the indicated TYPE; this variable will store the value to
8583 which the reference is bound. */
8586 make_temporary_var_for_ref_to_temp (tree decl, tree type)
8590 /* Create the variable. */
8591 var = create_temporary_var (type);
8593 /* Register the variable. */
8594 if (TREE_STATIC (decl))
8596 /* Namespace-scope or local static; give it a mangled name. */
8597 /* FIXME share comdat with decl? */
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, VEC(tree,gc) **cleanups,
8627 /* Create the temporary variable. */
8628 type = TREE_TYPE (expr);
8629 var = make_temporary_var_for_ref_to_temp (decl, type);
8630 layout_decl (var, 0);
8631 /* If the rvalue is the result of a function call it will be
8632 a TARGET_EXPR. If it is some other construct (such as a
8633 member access expression where the underlying object is
8634 itself the result of a function call), turn it into a
8635 TARGET_EXPR here. It is important that EXPR be a
8636 TARGET_EXPR below since otherwise the INIT_EXPR will
8637 attempt to make a bitwise copy of EXPR to initialize
8639 if (TREE_CODE (expr) != TARGET_EXPR)
8640 expr = get_target_expr (expr);
8642 if (TREE_CODE (decl) == FIELD_DECL
8643 && extra_warnings && !TREE_NO_WARNING (decl))
8645 warning (OPT_Wextra, "a temporary bound to %qD only persists "
8646 "until the constructor exits", decl);
8647 TREE_NO_WARNING (decl) = true;
8650 /* Recursively extend temps in this initializer. */
8651 TARGET_EXPR_INITIAL (expr)
8652 = extend_ref_init_temps (decl, TARGET_EXPR_INITIAL (expr), cleanups);
8654 /* If the initializer is constant, put it in DECL_INITIAL so we get
8655 static initialization and use in constant expressions. */
8656 init = maybe_constant_init (expr);
8657 if (TREE_CONSTANT (init))
8659 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
8661 /* 5.19 says that a constant expression can include an
8662 lvalue-rvalue conversion applied to "a glvalue of literal type
8663 that refers to a non-volatile temporary object initialized
8664 with a constant expression". Rather than try to communicate
8665 that this VAR_DECL is a temporary, just mark it constexpr.
8667 Currently this is only useful for initializer_list temporaries,
8668 since reference vars can't appear in constant expressions. */
8669 DECL_DECLARED_CONSTEXPR_P (var) = true;
8670 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
8671 TREE_CONSTANT (var) = true;
8673 DECL_INITIAL (var) = init;
8677 /* Create the INIT_EXPR that will initialize the temporary
8679 init = build2 (INIT_EXPR, type, var, expr);
8680 if (at_function_scope_p ())
8682 add_decl_expr (var);
8684 if (TREE_STATIC (var))
8685 init = add_stmt_to_compound (init, register_dtor_fn (var));
8688 tree cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error);
8690 VEC_safe_push (tree, gc, *cleanups, cleanup);
8693 /* We must be careful to destroy the temporary only
8694 after its initialization has taken place. If the
8695 initialization throws an exception, then the
8696 destructor should not be run. We cannot simply
8697 transform INIT into something like:
8699 (INIT, ({ CLEANUP_STMT; }))
8701 because emit_local_var always treats the
8702 initializer as a full-expression. Thus, the
8703 destructor would run too early; it would run at the
8704 end of initializing the reference variable, rather
8705 than at the end of the block enclosing the
8708 The solution is to pass back a cleanup expression
8709 which the caller is responsible for attaching to
8710 the statement tree. */
8714 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
8715 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
8716 static_aggregates = tree_cons (NULL_TREE, var,
8724 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
8725 initializing a variable of that TYPE. */
8728 initialize_reference (tree type, tree expr,
8729 int flags, tsubst_flags_t complain)
8734 if (type == error_mark_node || error_operand_p (expr))
8735 return error_mark_node;
8737 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8738 p = conversion_obstack_alloc (0);
8740 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
8742 if (!conv || conv->bad_p)
8744 if (complain & tf_error)
8747 convert_like (conv, expr, complain);
8748 else if (!CP_TYPE_CONST_P (TREE_TYPE (type))
8749 && !TYPE_REF_IS_RVALUE (type)
8750 && !real_lvalue_p (expr))
8751 error ("invalid initialization of non-const reference of "
8752 "type %qT from an rvalue of type %qT",
8753 type, TREE_TYPE (expr));
8755 error ("invalid initialization of reference of type "
8756 "%qT from expression of type %qT", type,
8759 return error_mark_node;
8762 gcc_assert (conv->kind == ck_ref_bind);
8764 /* Perform the conversion. */
8765 expr = convert_like (conv, expr, complain);
8767 /* Free all the conversions we allocated. */
8768 obstack_free (&conversion_obstack, p);
8773 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
8774 which is bound either to a reference or a std::initializer_list. */
8777 extend_ref_init_temps_1 (tree decl, tree init, VEC(tree,gc) **cleanups)
8782 if (TREE_CODE (sub) != ADDR_EXPR)
8784 /* Deal with binding to a subobject. */
8785 for (p = &TREE_OPERAND (sub, 0); TREE_CODE (*p) == COMPONENT_REF; )
8786 p = &TREE_OPERAND (*p, 0);
8787 if (TREE_CODE (*p) == TARGET_EXPR)
8789 tree subinit = NULL_TREE;
8790 *p = set_up_extended_ref_temp (decl, *p, cleanups, &subinit);
8792 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), subinit, init);
8797 /* INIT is part of the initializer for DECL. If there are any
8798 reference or initializer lists being initialized, extend their
8799 lifetime to match that of DECL. */
8802 extend_ref_init_temps (tree decl, tree init, VEC(tree,gc) **cleanups)
8804 tree type = TREE_TYPE (init);
8805 if (processing_template_decl)
8807 if (TREE_CODE (type) == REFERENCE_TYPE)
8808 init = extend_ref_init_temps_1 (decl, init, cleanups);
8809 else if (is_std_init_list (type))
8811 /* The temporary array underlying a std::initializer_list
8812 is handled like a reference temporary. */
8814 if (TREE_CODE (ctor) == TARGET_EXPR)
8815 ctor = TARGET_EXPR_INITIAL (ctor);
8816 if (TREE_CODE (ctor) == CONSTRUCTOR)
8818 tree array = CONSTRUCTOR_ELT (ctor, 0)->value;
8819 array = extend_ref_init_temps_1 (decl, array, cleanups);
8820 CONSTRUCTOR_ELT (ctor, 0)->value = array;
8823 else if (TREE_CODE (init) == CONSTRUCTOR)
8827 VEC(constructor_elt,gc) *elts = CONSTRUCTOR_ELTS (init);
8828 FOR_EACH_VEC_ELT (constructor_elt, elts, i, p)
8829 p->value = extend_ref_init_temps (decl, p->value, cleanups);
8835 /* Returns true iff TYPE is some variant of std::initializer_list. */
8838 is_std_init_list (tree type)
8840 /* Look through typedefs. */
8843 type = TYPE_MAIN_VARIANT (type);
8844 return (CLASS_TYPE_P (type)
8845 && CP_TYPE_CONTEXT (type) == std_node
8846 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
8849 /* Returns true iff DECL is a list constructor: i.e. a constructor which
8850 will accept an argument list of a single std::initializer_list<T>. */
8853 is_list_ctor (tree decl)
8855 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
8858 if (!args || args == void_list_node)
8861 arg = non_reference (TREE_VALUE (args));
8862 if (!is_std_init_list (arg))
8865 args = TREE_CHAIN (args);
8867 if (args && args != void_list_node && !TREE_PURPOSE (args))
8868 /* There are more non-defaulted parms. */
8874 #include "gt-cp-call.h"