1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
5 Free Software Foundation, Inc.
6 Contributed by Michael Tiemann (tiemann@cygnus.com) and
7 modified by Brendan Kehoe (brendan@cygnus.com).
9 This file is part of GCC.
11 GCC is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 3, or (at your option)
16 GCC is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
26 /* High-level class interface. */
30 #include "coretypes.h"
37 #include "diagnostic-core.h"
41 #include "langhooks.h"
42 #include "c-family/c-objc.h"
45 /* The various kinds of conversion. */
47 typedef enum conversion_kind {
63 /* The rank of the conversion. Order of the enumerals matters; better
64 conversions should come earlier in the list. */
66 typedef enum conversion_rank {
77 /* An implicit conversion sequence, in the sense of [over.best.ics].
78 The first conversion to be performed is at the end of the chain.
79 That conversion is always a cr_identity conversion. */
81 typedef struct conversion conversion;
83 /* The kind of conversion represented by this step. */
85 /* The rank of this conversion. */
87 BOOL_BITFIELD user_conv_p : 1;
88 BOOL_BITFIELD ellipsis_p : 1;
89 BOOL_BITFIELD this_p : 1;
90 /* True if this conversion would be permitted with a bending of
91 language standards, e.g. disregarding pointer qualifiers or
92 converting integers to pointers. */
93 BOOL_BITFIELD bad_p : 1;
94 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
95 temporary should be created to hold the result of the
97 BOOL_BITFIELD need_temporary_p : 1;
98 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
99 from a pointer-to-derived to pointer-to-base is being performed. */
100 BOOL_BITFIELD base_p : 1;
101 /* If KIND is ck_ref_bind, true when either an lvalue reference is
102 being bound to an lvalue expression or an rvalue reference is
103 being bound to an rvalue expression. If KIND is ck_rvalue,
104 true when we should treat an lvalue as an rvalue (12.8p33). If
105 KIND is ck_base, always false. */
106 BOOL_BITFIELD rvaluedness_matches_p: 1;
107 BOOL_BITFIELD check_narrowing: 1;
108 /* The type of the expression resulting from the conversion. */
111 /* The next conversion in the chain. Since the conversions are
112 arranged from outermost to innermost, the NEXT conversion will
113 actually be performed before this conversion. This variant is
114 used only when KIND is neither ck_identity nor ck_ambig. */
116 /* The expression at the beginning of the conversion chain. This
117 variant is used only if KIND is ck_identity or ck_ambig. */
119 /* The array of conversions for an initializer_list. */
122 /* The function candidate corresponding to this conversion
123 sequence. This field is only used if KIND is ck_user. */
124 struct z_candidate *cand;
127 #define CONVERSION_RANK(NODE) \
128 ((NODE)->bad_p ? cr_bad \
129 : (NODE)->ellipsis_p ? cr_ellipsis \
130 : (NODE)->user_conv_p ? cr_user \
133 #define BAD_CONVERSION_RANK(NODE) \
134 ((NODE)->ellipsis_p ? cr_ellipsis \
135 : (NODE)->user_conv_p ? cr_user \
138 static struct obstack conversion_obstack;
139 static bool conversion_obstack_initialized;
140 struct rejection_reason;
142 static struct z_candidate * tourney (struct z_candidate *);
143 static int equal_functions (tree, tree);
144 static int joust (struct z_candidate *, struct z_candidate *, bool);
145 static int compare_ics (conversion *, conversion *);
146 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
147 static tree build_java_interface_fn_ref (tree, tree);
148 #define convert_like(CONV, EXPR, COMPLAIN) \
149 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
150 /*issue_conversion_warnings=*/true, \
151 /*c_cast_p=*/false, (COMPLAIN))
152 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
153 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
154 /*issue_conversion_warnings=*/true, \
155 /*c_cast_p=*/false, (COMPLAIN))
156 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
157 bool, tsubst_flags_t);
158 static void op_error (enum tree_code, enum tree_code, tree, tree,
160 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
161 static void print_z_candidate (const char *, struct z_candidate *);
162 static void print_z_candidates (location_t, struct z_candidate *);
163 static tree build_this (tree);
164 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
165 static bool any_strictly_viable (struct z_candidate *);
166 static struct z_candidate *add_template_candidate
167 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
168 tree, tree, tree, int, unification_kind_t);
169 static struct z_candidate *add_template_candidate_real
170 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
171 tree, tree, tree, int, tree, unification_kind_t);
172 static struct z_candidate *add_template_conv_candidate
173 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
175 static void add_builtin_candidates
176 (struct z_candidate **, enum tree_code, enum tree_code,
178 static void add_builtin_candidate
179 (struct z_candidate **, enum tree_code, enum tree_code,
180 tree, tree, tree, tree *, tree *, int);
181 static bool is_complete (tree);
182 static void build_builtin_candidate
183 (struct z_candidate **, tree, tree, tree, tree *, tree *,
185 static struct z_candidate *add_conv_candidate
186 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
188 static struct z_candidate *add_function_candidate
189 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
191 static conversion *implicit_conversion (tree, tree, tree, bool, int);
192 static conversion *standard_conversion (tree, tree, tree, bool, int);
193 static conversion *reference_binding (tree, tree, tree, bool, int);
194 static conversion *build_conv (conversion_kind, tree, conversion *);
195 static conversion *build_list_conv (tree, tree, int);
196 static bool is_subseq (conversion *, conversion *);
197 static conversion *maybe_handle_ref_bind (conversion **);
198 static void maybe_handle_implicit_object (conversion **);
199 static struct z_candidate *add_candidate
200 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
201 conversion **, tree, tree, int, struct rejection_reason *);
202 static tree source_type (conversion *);
203 static void add_warning (struct z_candidate *, struct z_candidate *);
204 static bool reference_compatible_p (tree, tree);
205 static conversion *direct_reference_binding (tree, conversion *);
206 static bool promoted_arithmetic_type_p (tree);
207 static conversion *conditional_conversion (tree, tree);
208 static char *name_as_c_string (tree, tree, bool *);
209 static tree prep_operand (tree);
210 static void add_candidates (tree, tree, const VEC(tree,gc) *, tree, tree, bool,
211 tree, tree, int, struct z_candidate **);
212 static conversion *merge_conversion_sequences (conversion *, conversion *);
213 static bool magic_varargs_p (tree);
214 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
216 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
217 NAME can take many forms... */
220 check_dtor_name (tree basetype, tree name)
222 /* Just accept something we've already complained about. */
223 if (name == error_mark_node)
226 if (TREE_CODE (name) == TYPE_DECL)
227 name = TREE_TYPE (name);
228 else if (TYPE_P (name))
230 else if (TREE_CODE (name) == IDENTIFIER_NODE)
232 if ((MAYBE_CLASS_TYPE_P (basetype)
233 && name == constructor_name (basetype))
234 || (TREE_CODE (basetype) == ENUMERAL_TYPE
235 && name == TYPE_IDENTIFIER (basetype)))
238 name = get_type_value (name);
244 template <class T> struct S { ~S(); };
248 NAME will be a class template. */
249 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
253 if (!name || name == error_mark_node)
255 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
258 /* We want the address of a function or method. We avoid creating a
259 pointer-to-member function. */
262 build_addr_func (tree function)
264 tree type = TREE_TYPE (function);
266 /* We have to do these by hand to avoid real pointer to member
268 if (TREE_CODE (type) == METHOD_TYPE)
270 if (TREE_CODE (function) == OFFSET_REF)
272 tree object = build_address (TREE_OPERAND (function, 0));
273 return get_member_function_from_ptrfunc (&object,
274 TREE_OPERAND (function, 1));
276 function = build_address (function);
279 function = decay_conversion (function);
284 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
285 POINTER_TYPE to those. Note, pointer to member function types
286 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
287 two variants. build_call_a is the primitive taking an array of
288 arguments, while build_call_n is a wrapper that handles varargs. */
291 build_call_n (tree function, int n, ...)
294 return build_call_a (function, 0, NULL);
297 tree *argarray = XALLOCAVEC (tree, n);
302 for (i = 0; i < n; i++)
303 argarray[i] = va_arg (ap, tree);
305 return build_call_a (function, n, argarray);
309 /* Update various flags in cfun and the call itself based on what is being
310 called. Split out of build_call_a so that bot_manip can use it too. */
313 set_flags_from_callee (tree call)
316 tree decl = get_callee_fndecl (call);
318 /* We check both the decl and the type; a function may be known not to
319 throw without being declared throw(). */
320 nothrow = ((decl && TREE_NOTHROW (decl))
321 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call)))));
323 if (!nothrow && at_function_scope_p () && cfun && cp_function_chain)
324 cp_function_chain->can_throw = 1;
326 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
327 current_function_returns_abnormally = 1;
329 TREE_NOTHROW (call) = nothrow;
333 build_call_a (tree function, int n, tree *argarray)
340 function = build_addr_func (function);
342 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
343 fntype = TREE_TYPE (TREE_TYPE (function));
344 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
345 || TREE_CODE (fntype) == METHOD_TYPE);
346 result_type = TREE_TYPE (fntype);
347 /* An rvalue has no cv-qualifiers. */
348 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
349 result_type = cv_unqualified (result_type);
351 function = build_call_array_loc (input_location,
352 result_type, function, n, argarray);
353 set_flags_from_callee (function);
355 decl = get_callee_fndecl (function);
357 if (decl && !TREE_USED (decl))
359 /* We invoke build_call directly for several library
360 functions. These may have been declared normally if
361 we're building libgcc, so we can't just check
363 gcc_assert (DECL_ARTIFICIAL (decl)
364 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
369 if (decl && TREE_DEPRECATED (decl))
370 warn_deprecated_use (decl, NULL_TREE);
371 require_complete_eh_spec_types (fntype, decl);
373 TREE_HAS_CONSTRUCTOR (function) = (decl && DECL_CONSTRUCTOR_P (decl));
375 /* Don't pass empty class objects by value. This is useful
376 for tags in STL, which are used to control overload resolution.
377 We don't need to handle other cases of copying empty classes. */
378 if (! decl || ! DECL_BUILT_IN (decl))
379 for (i = 0; i < n; i++)
381 tree arg = CALL_EXPR_ARG (function, i);
382 if (is_empty_class (TREE_TYPE (arg))
383 && ! TREE_ADDRESSABLE (TREE_TYPE (arg)))
385 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (arg));
386 arg = build2 (COMPOUND_EXPR, TREE_TYPE (t), arg, t);
387 CALL_EXPR_ARG (function, i) = arg;
394 /* Build something of the form ptr->method (args)
395 or object.method (args). This can also build
396 calls to constructors, and find friends.
398 Member functions always take their class variable
401 INSTANCE is a class instance.
403 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
405 PARMS help to figure out what that NAME really refers to.
407 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
408 down to the real instance type to use for access checking. We need this
409 information to get protected accesses correct.
411 FLAGS is the logical disjunction of zero or more LOOKUP_
412 flags. See cp-tree.h for more info.
414 If this is all OK, calls build_function_call with the resolved
417 This function must also handle being called to perform
418 initialization, promotion/coercion of arguments, and
419 instantiation of default parameters.
421 Note that NAME may refer to an instance variable name. If
422 `operator()()' is defined for the type of that field, then we return
425 /* New overloading code. */
427 typedef struct z_candidate z_candidate;
429 typedef struct candidate_warning candidate_warning;
430 struct candidate_warning {
432 candidate_warning *next;
435 /* Information for providing diagnostics about why overloading failed. */
437 enum rejection_reason_code {
440 rr_explicit_conversion,
441 rr_template_conversion,
443 rr_bad_arg_conversion,
444 rr_template_unification,
445 rr_template_instantiation,
449 struct conversion_info {
450 /* The index of the argument, 0-based. */
452 /* The type of the actual argument. */
454 /* The type of the formal argument. */
458 struct rejection_reason {
459 enum rejection_reason_code code;
461 /* Information about an arity mismatch. */
463 /* The expected number of arguments. */
465 /* The actual number of arguments in the call. */
467 /* Whether the call was a varargs call. */
470 /* Information about an argument conversion mismatch. */
471 struct conversion_info conversion;
472 /* Same, but for bad argument conversions. */
473 struct conversion_info bad_conversion;
474 /* Information about template unification failures. These are the
475 parameters passed to fn_type_unification. */
483 unification_kind_t strict;
485 } template_unification;
486 /* Information about template instantiation failures. These are the
487 parameters passed to instantiate_template. */
491 } template_instantiation;
496 /* The FUNCTION_DECL that will be called if this candidate is
497 selected by overload resolution. */
499 /* If not NULL_TREE, the first argument to use when calling this
502 /* The rest of the arguments to use when calling this function. If
503 there are no further arguments this may be NULL or it may be an
505 const VEC(tree,gc) *args;
506 /* The implicit conversion sequences for each of the arguments to
509 /* The number of implicit conversion sequences. */
511 /* If FN is a user-defined conversion, the standard conversion
512 sequence from the type returned by FN to the desired destination
514 conversion *second_conv;
516 struct rejection_reason *reason;
517 /* If FN is a member function, the binfo indicating the path used to
518 qualify the name of FN at the call site. This path is used to
519 determine whether or not FN is accessible if it is selected by
520 overload resolution. The DECL_CONTEXT of FN will always be a
521 (possibly improper) base of this binfo. */
523 /* If FN is a non-static member function, the binfo indicating the
524 subobject to which the `this' pointer should be converted if FN
525 is selected by overload resolution. The type pointed to the by
526 the `this' pointer must correspond to the most derived class
527 indicated by the CONVERSION_PATH. */
528 tree conversion_path;
531 candidate_warning *warnings;
535 /* Returns true iff T is a null pointer constant in the sense of
539 null_ptr_cst_p (tree t)
543 A null pointer constant is an integral constant expression
544 (_expr.const_) rvalue of integer type that evaluates to zero or
545 an rvalue of type std::nullptr_t. */
546 if (NULLPTR_TYPE_P (TREE_TYPE (t)))
548 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
550 /* Core issue 903 says only literal 0 is a null pointer constant. */
551 if (cxx_dialect < cxx0x)
553 t = integral_constant_value (t);
556 if (integer_zerop (t) && !TREE_OVERFLOW (t))
562 /* Returns true iff T is a null member pointer value (4.11). */
565 null_member_pointer_value_p (tree t)
567 tree type = TREE_TYPE (t);
570 else if (TYPE_PTRMEMFUNC_P (type))
571 return (TREE_CODE (t) == CONSTRUCTOR
572 && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value));
573 else if (TYPE_PTRMEM_P (type))
574 return integer_all_onesp (t);
579 /* Returns nonzero if PARMLIST consists of only default parms,
580 ellipsis, and/or undeduced parameter packs. */
583 sufficient_parms_p (const_tree parmlist)
585 for (; parmlist && parmlist != void_list_node;
586 parmlist = TREE_CHAIN (parmlist))
587 if (!TREE_PURPOSE (parmlist)
588 && !PACK_EXPANSION_P (TREE_VALUE (parmlist)))
593 /* Allocate N bytes of memory from the conversion obstack. The memory
594 is zeroed before being returned. */
597 conversion_obstack_alloc (size_t n)
600 if (!conversion_obstack_initialized)
602 gcc_obstack_init (&conversion_obstack);
603 conversion_obstack_initialized = true;
605 p = obstack_alloc (&conversion_obstack, n);
610 /* Allocate rejection reasons. */
612 static struct rejection_reason *
613 alloc_rejection (enum rejection_reason_code code)
615 struct rejection_reason *p;
616 p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p);
621 static struct rejection_reason *
622 arity_rejection (tree first_arg, int expected, int actual)
624 struct rejection_reason *r = alloc_rejection (rr_arity);
625 int adjust = first_arg != NULL_TREE;
626 r->u.arity.expected = expected - adjust;
627 r->u.arity.actual = actual - adjust;
631 static struct rejection_reason *
632 arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
634 struct rejection_reason *r = alloc_rejection (rr_arg_conversion);
635 int adjust = first_arg != NULL_TREE;
636 r->u.conversion.n_arg = n_arg - adjust;
637 r->u.conversion.from_type = from;
638 r->u.conversion.to_type = to;
642 static struct rejection_reason *
643 bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
645 struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion);
646 int adjust = first_arg != NULL_TREE;
647 r->u.bad_conversion.n_arg = n_arg - adjust;
648 r->u.bad_conversion.from_type = from;
649 r->u.bad_conversion.to_type = to;
653 static struct rejection_reason *
654 explicit_conversion_rejection (tree from, tree to)
656 struct rejection_reason *r = alloc_rejection (rr_explicit_conversion);
657 r->u.conversion.n_arg = 0;
658 r->u.conversion.from_type = from;
659 r->u.conversion.to_type = to;
663 static struct rejection_reason *
664 template_conversion_rejection (tree from, tree to)
666 struct rejection_reason *r = alloc_rejection (rr_template_conversion);
667 r->u.conversion.n_arg = 0;
668 r->u.conversion.from_type = from;
669 r->u.conversion.to_type = to;
673 static struct rejection_reason *
674 template_unification_rejection (tree tmpl, tree explicit_targs, tree targs,
675 const tree *args, unsigned int nargs,
676 tree return_type, unification_kind_t strict,
679 size_t args_n_bytes = sizeof (*args) * nargs;
680 tree *args1 = (tree *) conversion_obstack_alloc (args_n_bytes);
681 struct rejection_reason *r = alloc_rejection (rr_template_unification);
682 r->u.template_unification.tmpl = tmpl;
683 r->u.template_unification.explicit_targs = explicit_targs;
684 r->u.template_unification.targs = targs;
685 /* Copy args to our own storage. */
686 memcpy (args1, args, args_n_bytes);
687 r->u.template_unification.args = args1;
688 r->u.template_unification.nargs = nargs;
689 r->u.template_unification.return_type = return_type;
690 r->u.template_unification.strict = strict;
691 r->u.template_unification.flags = flags;
695 static struct rejection_reason *
696 template_unification_error_rejection (void)
698 return alloc_rejection (rr_template_unification);
701 static struct rejection_reason *
702 template_instantiation_rejection (tree tmpl, tree targs)
704 struct rejection_reason *r = alloc_rejection (rr_template_instantiation);
705 r->u.template_instantiation.tmpl = tmpl;
706 r->u.template_instantiation.targs = targs;
710 static struct rejection_reason *
711 invalid_copy_with_fn_template_rejection (void)
713 struct rejection_reason *r = alloc_rejection (rr_invalid_copy);
717 /* Dynamically allocate a conversion. */
720 alloc_conversion (conversion_kind kind)
723 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
728 #ifdef ENABLE_CHECKING
730 /* Make sure that all memory on the conversion obstack has been
734 validate_conversion_obstack (void)
736 if (conversion_obstack_initialized)
737 gcc_assert ((obstack_next_free (&conversion_obstack)
738 == obstack_base (&conversion_obstack)));
741 #endif /* ENABLE_CHECKING */
743 /* Dynamically allocate an array of N conversions. */
746 alloc_conversions (size_t n)
748 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
752 build_conv (conversion_kind code, tree type, conversion *from)
755 conversion_rank rank = CONVERSION_RANK (from);
757 /* Note that the caller is responsible for filling in t->cand for
758 user-defined conversions. */
759 t = alloc_conversion (code);
782 t->user_conv_p = (code == ck_user || from->user_conv_p);
783 t->bad_p = from->bad_p;
788 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
789 specialization of std::initializer_list<T>, if such a conversion is
793 build_list_conv (tree type, tree ctor, int flags)
795 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
796 unsigned len = CONSTRUCTOR_NELTS (ctor);
797 conversion **subconvs = alloc_conversions (len);
802 /* Within a list-initialization we can have more user-defined
804 flags &= ~LOOKUP_NO_CONVERSION;
805 /* But no narrowing conversions. */
806 flags |= LOOKUP_NO_NARROWING;
808 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
811 = implicit_conversion (elttype, TREE_TYPE (val), val,
819 t = alloc_conversion (ck_list);
821 t->u.list = subconvs;
824 for (i = 0; i < len; ++i)
826 conversion *sub = subconvs[i];
827 if (sub->rank > t->rank)
829 if (sub->user_conv_p)
830 t->user_conv_p = true;
838 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
839 is a valid aggregate initializer for array type ATYPE. */
842 can_convert_array (tree atype, tree ctor, int flags)
845 tree elttype = TREE_TYPE (atype);
846 for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
848 tree val = CONSTRUCTOR_ELT (ctor, i)->value;
850 if (TREE_CODE (elttype) == ARRAY_TYPE
851 && TREE_CODE (val) == CONSTRUCTOR)
852 ok = can_convert_array (elttype, val, flags);
854 ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags);
861 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
862 aggregate class, if such a conversion is possible. */
865 build_aggr_conv (tree type, tree ctor, int flags)
867 unsigned HOST_WIDE_INT i = 0;
869 tree field = next_initializable_field (TYPE_FIELDS (type));
870 tree empty_ctor = NULL_TREE;
872 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
874 tree ftype = TREE_TYPE (field);
878 if (i < CONSTRUCTOR_NELTS (ctor))
879 val = CONSTRUCTOR_ELT (ctor, i)->value;
882 if (empty_ctor == NULL_TREE)
883 empty_ctor = build_constructor (init_list_type_node, NULL);
888 if (TREE_CODE (ftype) == ARRAY_TYPE
889 && TREE_CODE (val) == CONSTRUCTOR)
890 ok = can_convert_array (ftype, val, flags);
892 ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags);
897 if (TREE_CODE (type) == UNION_TYPE)
901 if (i < CONSTRUCTOR_NELTS (ctor))
904 c = alloc_conversion (ck_aggr);
907 c->user_conv_p = true;
912 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
913 array type, if such a conversion is possible. */
916 build_array_conv (tree type, tree ctor, int flags)
919 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
920 tree elttype = TREE_TYPE (type);
925 enum conversion_rank rank = cr_exact;
927 if (TYPE_DOMAIN (type))
929 unsigned HOST_WIDE_INT alen = tree_low_cst (array_type_nelts_top (type), 1);
934 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
937 = implicit_conversion (elttype, TREE_TYPE (val), val,
942 if (sub->rank > rank)
944 if (sub->user_conv_p)
950 c = alloc_conversion (ck_aggr);
953 c->user_conv_p = user;
959 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
960 complex type, if such a conversion is possible. */
963 build_complex_conv (tree type, tree ctor, int flags)
966 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
967 tree elttype = TREE_TYPE (type);
972 enum conversion_rank rank = cr_exact;
977 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
980 = implicit_conversion (elttype, TREE_TYPE (val), val,
985 if (sub->rank > rank)
987 if (sub->user_conv_p)
993 c = alloc_conversion (ck_aggr);
996 c->user_conv_p = user;
1002 /* Build a representation of the identity conversion from EXPR to
1003 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1006 build_identity_conv (tree type, tree expr)
1010 c = alloc_conversion (ck_identity);
1017 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1018 were multiple user-defined conversions to accomplish the job.
1019 Build a conversion that indicates that ambiguity. */
1022 build_ambiguous_conv (tree type, tree expr)
1026 c = alloc_conversion (ck_ambig);
1034 strip_top_quals (tree t)
1036 if (TREE_CODE (t) == ARRAY_TYPE)
1038 return cp_build_qualified_type (t, 0);
1041 /* Returns the standard conversion path (see [conv]) from type FROM to type
1042 TO, if any. For proper handling of null pointer constants, you must
1043 also pass the expression EXPR to convert from. If C_CAST_P is true,
1044 this conversion is coming from a C-style cast. */
1047 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
1050 enum tree_code fcode, tcode;
1052 bool fromref = false;
1055 to = non_reference (to);
1056 if (TREE_CODE (from) == REFERENCE_TYPE)
1059 from = TREE_TYPE (from);
1062 to = strip_top_quals (to);
1063 from = strip_top_quals (from);
1065 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
1066 && expr && type_unknown_p (expr))
1068 tsubst_flags_t tflags = tf_conv;
1069 if (!(flags & LOOKUP_PROTECT))
1070 tflags |= tf_no_access_control;
1071 expr = instantiate_type (to, expr, tflags);
1072 if (expr == error_mark_node)
1074 from = TREE_TYPE (expr);
1077 fcode = TREE_CODE (from);
1078 tcode = TREE_CODE (to);
1080 conv = build_identity_conv (from, expr);
1081 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
1083 from = type_decays_to (from);
1084 fcode = TREE_CODE (from);
1085 conv = build_conv (ck_lvalue, from, conv);
1087 else if (fromref || (expr && lvalue_p (expr)))
1092 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
1095 from = strip_top_quals (bitfield_type);
1096 fcode = TREE_CODE (from);
1099 conv = build_conv (ck_rvalue, from, conv);
1100 if (flags & LOOKUP_PREFER_RVALUE)
1101 conv->rvaluedness_matches_p = true;
1104 /* Allow conversion between `__complex__' data types. */
1105 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
1107 /* The standard conversion sequence to convert FROM to TO is
1108 the standard conversion sequence to perform componentwise
1110 conversion *part_conv = standard_conversion
1111 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
1115 conv = build_conv (part_conv->kind, to, conv);
1116 conv->rank = part_conv->rank;
1124 if (same_type_p (from, to))
1126 if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue)
1127 conv->type = qualified_to;
1132 A null pointer constant can be converted to a pointer type; ... A
1133 null pointer constant of integral type can be converted to an
1134 rvalue of type std::nullptr_t. */
1135 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to)
1136 || NULLPTR_TYPE_P (to))
1137 && expr && null_ptr_cst_p (expr))
1138 conv = build_conv (ck_std, to, conv);
1139 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
1140 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
1142 /* For backwards brain damage compatibility, allow interconversion of
1143 pointers and integers with a pedwarn. */
1144 conv = build_conv (ck_std, to, conv);
1147 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
1149 /* For backwards brain damage compatibility, allow interconversion of
1150 enums and integers with a pedwarn. */
1151 conv = build_conv (ck_std, to, conv);
1154 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
1155 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
1160 if (tcode == POINTER_TYPE
1161 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
1164 else if (VOID_TYPE_P (TREE_TYPE (to))
1165 && !TYPE_PTRMEM_P (from)
1166 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
1168 tree nfrom = TREE_TYPE (from);
1169 from = build_pointer_type
1170 (cp_build_qualified_type (void_type_node,
1171 cp_type_quals (nfrom)));
1172 conv = build_conv (ck_ptr, from, conv);
1174 else if (TYPE_PTRMEM_P (from))
1176 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
1177 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
1179 if (DERIVED_FROM_P (fbase, tbase)
1180 && (same_type_ignoring_top_level_qualifiers_p
1181 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
1182 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
1184 from = build_ptrmem_type (tbase,
1185 TYPE_PTRMEM_POINTED_TO_TYPE (from));
1186 conv = build_conv (ck_pmem, from, conv);
1188 else if (!same_type_p (fbase, tbase))
1191 else if (CLASS_TYPE_P (TREE_TYPE (from))
1192 && CLASS_TYPE_P (TREE_TYPE (to))
1195 An rvalue of type "pointer to cv D," where D is a
1196 class type, can be converted to an rvalue of type
1197 "pointer to cv B," where B is a base class (clause
1198 _class.derived_) of D. If B is an inaccessible
1199 (clause _class.access_) or ambiguous
1200 (_class.member.lookup_) base class of D, a program
1201 that necessitates this conversion is ill-formed.
1202 Therefore, we use DERIVED_FROM_P, and do not check
1203 access or uniqueness. */
1204 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
1207 cp_build_qualified_type (TREE_TYPE (to),
1208 cp_type_quals (TREE_TYPE (from)));
1209 from = build_pointer_type (from);
1210 conv = build_conv (ck_ptr, from, conv);
1211 conv->base_p = true;
1214 if (tcode == POINTER_TYPE)
1216 to_pointee = TREE_TYPE (to);
1217 from_pointee = TREE_TYPE (from);
1221 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
1222 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
1225 if (same_type_p (from, to))
1227 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
1228 /* In a C-style cast, we ignore CV-qualification because we
1229 are allowed to perform a static_cast followed by a
1231 conv = build_conv (ck_qual, to, conv);
1232 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
1233 conv = build_conv (ck_qual, to, conv);
1234 else if (expr && string_conv_p (to, expr, 0))
1235 /* converting from string constant to char *. */
1236 conv = build_conv (ck_qual, to, conv);
1237 /* Allow conversions among compatible ObjC pointer types (base
1238 conversions have been already handled above). */
1239 else if (c_dialect_objc ()
1240 && objc_compare_types (to, from, -4, NULL_TREE))
1241 conv = build_conv (ck_ptr, to, conv);
1242 else if (ptr_reasonably_similar (to_pointee, from_pointee))
1244 conv = build_conv (ck_ptr, to, conv);
1252 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
1254 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
1255 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
1256 tree fbase = class_of_this_parm (fromfn);
1257 tree tbase = class_of_this_parm (tofn);
1259 if (!DERIVED_FROM_P (fbase, tbase)
1260 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
1261 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
1262 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
1263 || cp_type_quals (fbase) != cp_type_quals (tbase))
1266 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
1267 from = build_ptrmemfunc_type (build_pointer_type (from));
1268 conv = build_conv (ck_pmem, from, conv);
1269 conv->base_p = true;
1271 else if (tcode == BOOLEAN_TYPE)
1275 An rvalue of arithmetic, unscoped enumeration, pointer, or
1276 pointer to member type can be converted to an rvalue of type
1277 bool. ... An rvalue of type std::nullptr_t can be converted
1278 to an rvalue of type bool; */
1279 if (ARITHMETIC_TYPE_P (from)
1280 || UNSCOPED_ENUM_P (from)
1281 || fcode == POINTER_TYPE
1282 || TYPE_PTR_TO_MEMBER_P (from)
1283 || NULLPTR_TYPE_P (from))
1285 conv = build_conv (ck_std, to, conv);
1286 if (fcode == POINTER_TYPE
1287 || TYPE_PTRMEM_P (from)
1288 || (TYPE_PTRMEMFUNC_P (from)
1289 && conv->rank < cr_pbool)
1290 || NULLPTR_TYPE_P (from))
1291 conv->rank = cr_pbool;
1297 /* We don't check for ENUMERAL_TYPE here because there are no standard
1298 conversions to enum type. */
1299 /* As an extension, allow conversion to complex type. */
1300 else if (ARITHMETIC_TYPE_P (to))
1302 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
1303 || SCOPED_ENUM_P (from))
1305 conv = build_conv (ck_std, to, conv);
1307 /* Give this a better rank if it's a promotion. */
1308 if (same_type_p (to, type_promotes_to (from))
1309 && conv->u.next->rank <= cr_promotion)
1310 conv->rank = cr_promotion;
1312 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
1313 && vector_types_convertible_p (from, to, false))
1314 return build_conv (ck_std, to, conv);
1315 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
1316 && is_properly_derived_from (from, to))
1318 if (conv->kind == ck_rvalue)
1319 conv = conv->u.next;
1320 conv = build_conv (ck_base, to, conv);
1321 /* The derived-to-base conversion indicates the initialization
1322 of a parameter with base type from an object of a derived
1323 type. A temporary object is created to hold the result of
1324 the conversion unless we're binding directly to a reference. */
1325 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
1330 if (flags & LOOKUP_NO_NARROWING)
1331 conv->check_narrowing = true;
1336 /* Returns nonzero if T1 is reference-related to T2. */
1339 reference_related_p (tree t1, tree t2)
1341 if (t1 == error_mark_node || t2 == error_mark_node)
1344 t1 = TYPE_MAIN_VARIANT (t1);
1345 t2 = TYPE_MAIN_VARIANT (t2);
1349 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1350 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1352 return (same_type_p (t1, t2)
1353 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1354 && DERIVED_FROM_P (t1, t2)));
1357 /* Returns nonzero if T1 is reference-compatible with T2. */
1360 reference_compatible_p (tree t1, tree t2)
1364 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1365 reference-related to T2 and cv1 is the same cv-qualification as,
1366 or greater cv-qualification than, cv2. */
1367 return (reference_related_p (t1, t2)
1368 && at_least_as_qualified_p (t1, t2));
1371 /* A reference of the indicated TYPE is being bound directly to the
1372 expression represented by the implicit conversion sequence CONV.
1373 Return a conversion sequence for this binding. */
1376 direct_reference_binding (tree type, conversion *conv)
1380 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1381 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1383 t = TREE_TYPE (type);
1387 When a parameter of reference type binds directly
1388 (_dcl.init.ref_) to an argument expression, the implicit
1389 conversion sequence is the identity conversion, unless the
1390 argument expression has a type that is a derived class of the
1391 parameter type, in which case the implicit conversion sequence is
1392 a derived-to-base Conversion.
1394 If the parameter binds directly to the result of applying a
1395 conversion function to the argument expression, the implicit
1396 conversion sequence is a user-defined conversion sequence
1397 (_over.ics.user_), with the second standard conversion sequence
1398 either an identity conversion or, if the conversion function
1399 returns an entity of a type that is a derived class of the
1400 parameter type, a derived-to-base conversion. */
1401 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1403 /* Represent the derived-to-base conversion. */
1404 conv = build_conv (ck_base, t, conv);
1405 /* We will actually be binding to the base-class subobject in
1406 the derived class, so we mark this conversion appropriately.
1407 That way, convert_like knows not to generate a temporary. */
1408 conv->need_temporary_p = false;
1410 return build_conv (ck_ref_bind, type, conv);
1413 /* Returns the conversion path from type FROM to reference type TO for
1414 purposes of reference binding. For lvalue binding, either pass a
1415 reference type to FROM or an lvalue expression to EXPR. If the
1416 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1417 the conversion returned. If C_CAST_P is true, this
1418 conversion is coming from a C-style cast. */
1421 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1423 conversion *conv = NULL;
1424 tree to = TREE_TYPE (rto);
1429 cp_lvalue_kind gl_kind;
1432 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1434 expr = instantiate_type (to, expr, tf_none);
1435 if (expr == error_mark_node)
1437 from = TREE_TYPE (expr);
1440 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1442 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1443 conv = implicit_conversion (to, from, expr, c_cast_p,
1445 if (!CLASS_TYPE_P (to)
1446 && CONSTRUCTOR_NELTS (expr) == 1)
1448 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1449 if (error_operand_p (expr))
1451 from = TREE_TYPE (expr);
1455 if (TREE_CODE (from) == REFERENCE_TYPE)
1457 from = TREE_TYPE (from);
1458 if (!TYPE_REF_IS_RVALUE (rfrom)
1459 || TREE_CODE (from) == FUNCTION_TYPE)
1460 gl_kind = clk_ordinary;
1462 gl_kind = clk_rvalueref;
1466 gl_kind = lvalue_kind (expr);
1467 if (gl_kind & clk_class)
1468 /* A class prvalue is not a glvalue. */
1473 is_lvalue = gl_kind && !(gl_kind & clk_rvalueref);
1476 if ((gl_kind & clk_bitfield) != 0)
1477 tfrom = unlowered_expr_type (expr);
1479 /* Figure out whether or not the types are reference-related and
1480 reference compatible. We have do do this after stripping
1481 references from FROM. */
1482 related_p = reference_related_p (to, tfrom);
1483 /* If this is a C cast, first convert to an appropriately qualified
1484 type, so that we can later do a const_cast to the desired type. */
1485 if (related_p && c_cast_p
1486 && !at_least_as_qualified_p (to, tfrom))
1487 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1488 compatible_p = reference_compatible_p (to, tfrom);
1490 /* Directly bind reference when target expression's type is compatible with
1491 the reference and expression is an lvalue. In DR391, the wording in
1492 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1493 const and rvalue references to rvalues of compatible class type.
1494 We should also do direct bindings for non-class xvalues. */
1497 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1498 && !(flags & LOOKUP_NO_RVAL_BIND))
1499 || TYPE_REF_IS_RVALUE (rto))
1501 || (!(flags & LOOKUP_NO_TEMP_BIND)
1502 && (CLASS_TYPE_P (from)
1503 || TREE_CODE (from) == ARRAY_TYPE))))))
1507 If the initializer expression
1509 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1510 is reference-compatible with "cv2 T2,"
1512 the reference is bound directly to the initializer expression
1516 If the initializer expression is an rvalue, with T2 a class type,
1517 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1518 is bound to the object represented by the rvalue or to a sub-object
1519 within that object. */
1521 conv = build_identity_conv (tfrom, expr);
1522 conv = direct_reference_binding (rto, conv);
1524 if (flags & LOOKUP_PREFER_RVALUE)
1525 /* The top-level caller requested that we pretend that the lvalue
1526 be treated as an rvalue. */
1527 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1528 else if (TREE_CODE (rfrom) == REFERENCE_TYPE)
1529 /* Handle rvalue reference to function properly. */
1530 conv->rvaluedness_matches_p
1531 = (TYPE_REF_IS_RVALUE (rto) == TYPE_REF_IS_RVALUE (rfrom));
1533 conv->rvaluedness_matches_p
1534 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1536 if ((gl_kind & clk_bitfield) != 0
1537 || ((gl_kind & clk_packed) != 0 && !TYPE_PACKED (to)))
1538 /* For the purposes of overload resolution, we ignore the fact
1539 this expression is a bitfield or packed field. (In particular,
1540 [over.ics.ref] says specifically that a function with a
1541 non-const reference parameter is viable even if the
1542 argument is a bitfield.)
1544 However, when we actually call the function we must create
1545 a temporary to which to bind the reference. If the
1546 reference is volatile, or isn't const, then we cannot make
1547 a temporary, so we just issue an error when the conversion
1549 conv->need_temporary_p = true;
1551 /* Don't allow binding of lvalues (other than function lvalues) to
1552 rvalue references. */
1553 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1554 && TREE_CODE (to) != FUNCTION_TYPE
1555 && !(flags & LOOKUP_PREFER_RVALUE))
1560 /* [class.conv.fct] A conversion function is never used to convert a
1561 (possibly cv-qualified) object to the (possibly cv-qualified) same
1562 object type (or a reference to it), to a (possibly cv-qualified) base
1563 class of that type (or a reference to it).... */
1564 else if (CLASS_TYPE_P (from) && !related_p
1565 && !(flags & LOOKUP_NO_CONVERSION))
1569 If the initializer expression
1571 -- has a class type (i.e., T2 is a class type) can be
1572 implicitly converted to an lvalue of type "cv3 T3," where
1573 "cv1 T1" is reference-compatible with "cv3 T3". (this
1574 conversion is selected by enumerating the applicable
1575 conversion functions (_over.match.ref_) and choosing the
1576 best one through overload resolution. (_over.match_).
1578 the reference is bound to the lvalue result of the conversion
1579 in the second case. */
1580 z_candidate *cand = build_user_type_conversion_1 (rto, expr, flags);
1582 return cand->second_conv;
1585 /* From this point on, we conceptually need temporaries, even if we
1586 elide them. Only the cases above are "direct bindings". */
1587 if (flags & LOOKUP_NO_TEMP_BIND)
1592 When a parameter of reference type is not bound directly to an
1593 argument expression, the conversion sequence is the one required
1594 to convert the argument expression to the underlying type of the
1595 reference according to _over.best.ics_. Conceptually, this
1596 conversion sequence corresponds to copy-initializing a temporary
1597 of the underlying type with the argument expression. Any
1598 difference in top-level cv-qualification is subsumed by the
1599 initialization itself and does not constitute a conversion. */
1603 Otherwise, the reference shall be to a non-volatile const type.
1605 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1606 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1611 Otherwise, a temporary of type "cv1 T1" is created and
1612 initialized from the initializer expression using the rules for a
1613 non-reference copy initialization. If T1 is reference-related to
1614 T2, cv1 must be the same cv-qualification as, or greater
1615 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1616 if (related_p && !at_least_as_qualified_p (to, from))
1619 /* We're generating a temporary now, but don't bind any more in the
1620 conversion (specifically, don't slice the temporary returned by a
1621 conversion operator). */
1622 flags |= LOOKUP_NO_TEMP_BIND;
1624 /* Core issue 899: When [copy-]initializing a temporary to be bound
1625 to the first parameter of a copy constructor (12.8) called with
1626 a single argument in the context of direct-initialization,
1627 explicit conversion functions are also considered.
1629 So don't set LOOKUP_ONLYCONVERTING in that case. */
1630 if (!(flags & LOOKUP_COPY_PARM))
1631 flags |= LOOKUP_ONLYCONVERTING;
1634 conv = implicit_conversion (to, from, expr, c_cast_p,
1639 conv = build_conv (ck_ref_bind, rto, conv);
1640 /* This reference binding, unlike those above, requires the
1641 creation of a temporary. */
1642 conv->need_temporary_p = true;
1643 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1648 /* Returns the implicit conversion sequence (see [over.ics]) from type
1649 FROM to type TO. The optional expression EXPR may affect the
1650 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1651 true, this conversion is coming from a C-style cast. */
1654 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1659 if (from == error_mark_node || to == error_mark_node
1660 || expr == error_mark_node)
1663 if (TREE_CODE (to) == REFERENCE_TYPE)
1664 conv = reference_binding (to, from, expr, c_cast_p, flags);
1666 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1671 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1673 if (is_std_init_list (to))
1674 return build_list_conv (to, expr, flags);
1676 /* As an extension, allow list-initialization of _Complex. */
1677 if (TREE_CODE (to) == COMPLEX_TYPE)
1679 conv = build_complex_conv (to, expr, flags);
1684 /* Allow conversion from an initializer-list with one element to a
1686 if (SCALAR_TYPE_P (to))
1688 int nelts = CONSTRUCTOR_NELTS (expr);
1692 elt = build_value_init (to, tf_none);
1693 else if (nelts == 1)
1694 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1696 elt = error_mark_node;
1698 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1702 conv->check_narrowing = true;
1703 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1704 /* Too many levels of braces, i.e. '{{1}}'. */
1709 else if (TREE_CODE (to) == ARRAY_TYPE)
1710 return build_array_conv (to, expr, flags);
1713 if (expr != NULL_TREE
1714 && (MAYBE_CLASS_TYPE_P (from)
1715 || MAYBE_CLASS_TYPE_P (to))
1716 && (flags & LOOKUP_NO_CONVERSION) == 0)
1718 struct z_candidate *cand;
1719 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING
1720 |LOOKUP_NO_NARROWING));
1722 if (CLASS_TYPE_P (to)
1723 && BRACE_ENCLOSED_INITIALIZER_P (expr)
1724 && !CLASSTYPE_NON_AGGREGATE (complete_type (to)))
1725 return build_aggr_conv (to, expr, flags);
1727 cand = build_user_type_conversion_1 (to, expr, convflags);
1729 conv = cand->second_conv;
1731 /* We used to try to bind a reference to a temporary here, but that
1732 is now handled after the recursive call to this function at the end
1733 of reference_binding. */
1740 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1741 functions. ARGS will not be changed until a single candidate is
1744 static struct z_candidate *
1745 add_candidate (struct z_candidate **candidates,
1746 tree fn, tree first_arg, const VEC(tree,gc) *args,
1747 size_t num_convs, conversion **convs,
1748 tree access_path, tree conversion_path,
1749 int viable, struct rejection_reason *reason)
1751 struct z_candidate *cand = (struct z_candidate *)
1752 conversion_obstack_alloc (sizeof (struct z_candidate));
1755 cand->first_arg = first_arg;
1757 cand->convs = convs;
1758 cand->num_convs = num_convs;
1759 cand->access_path = access_path;
1760 cand->conversion_path = conversion_path;
1761 cand->viable = viable;
1762 cand->reason = reason;
1763 cand->next = *candidates;
1769 /* Return the number of remaining arguments in the parameter list
1770 beginning with ARG. */
1773 remaining_arguments (tree arg)
1777 for (n = 0; arg != NULL_TREE && arg != void_list_node;
1778 arg = TREE_CHAIN (arg))
1784 /* Create an overload candidate for the function or method FN called
1785 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1786 FLAGS is passed on to implicit_conversion.
1788 This does not change ARGS.
1790 CTYPE, if non-NULL, is the type we want to pretend this function
1791 comes from for purposes of overload resolution. */
1793 static struct z_candidate *
1794 add_function_candidate (struct z_candidate **candidates,
1795 tree fn, tree ctype, tree first_arg,
1796 const VEC(tree,gc) *args, tree access_path,
1797 tree conversion_path, int flags)
1799 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1803 tree orig_first_arg = first_arg;
1806 struct rejection_reason *reason = NULL;
1808 /* At this point we should not see any functions which haven't been
1809 explicitly declared, except for friend functions which will have
1810 been found using argument dependent lookup. */
1811 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1813 /* The `this', `in_chrg' and VTT arguments to constructors are not
1814 considered in overload resolution. */
1815 if (DECL_CONSTRUCTOR_P (fn))
1817 parmlist = skip_artificial_parms_for (fn, parmlist);
1818 skip = num_artificial_parms_for (fn);
1819 if (skip > 0 && first_arg != NULL_TREE)
1822 first_arg = NULL_TREE;
1828 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1829 convs = alloc_conversions (len);
1831 /* 13.3.2 - Viable functions [over.match.viable]
1832 First, to be a viable function, a candidate function shall have enough
1833 parameters to agree in number with the arguments in the list.
1835 We need to check this first; otherwise, checking the ICSes might cause
1836 us to produce an ill-formed template instantiation. */
1838 parmnode = parmlist;
1839 for (i = 0; i < len; ++i)
1841 if (parmnode == NULL_TREE || parmnode == void_list_node)
1843 parmnode = TREE_CHAIN (parmnode);
1846 if ((i < len && parmnode)
1847 || !sufficient_parms_p (parmnode))
1849 int remaining = remaining_arguments (parmnode);
1851 reason = arity_rejection (first_arg, i + remaining, len);
1853 /* When looking for a function from a subobject from an implicit
1854 copy/move constructor/operator=, don't consider anything that takes (a
1855 reference to) an unrelated type. See c++/44909 and core 1092. */
1856 else if (parmlist && (flags & LOOKUP_DEFAULTED))
1858 if (DECL_CONSTRUCTOR_P (fn))
1860 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
1861 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
1867 parmnode = chain_index (i-1, parmlist);
1868 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
1873 /* This only applies at the top level. */
1874 flags &= ~LOOKUP_DEFAULTED;
1880 /* Second, for F to be a viable function, there shall exist for each
1881 argument an implicit conversion sequence that converts that argument
1882 to the corresponding parameter of F. */
1884 parmnode = parmlist;
1886 for (i = 0; i < len; ++i)
1888 tree arg, argtype, to_type;
1892 if (parmnode == void_list_node)
1895 if (i == 0 && first_arg != NULL_TREE)
1898 arg = VEC_index (tree, args,
1899 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1900 argtype = lvalue_type (arg);
1902 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1903 && ! DECL_CONSTRUCTOR_P (fn));
1907 tree parmtype = TREE_VALUE (parmnode);
1910 parmnode = TREE_CHAIN (parmnode);
1912 /* The type of the implicit object parameter ('this') for
1913 overload resolution is not always the same as for the
1914 function itself; conversion functions are considered to
1915 be members of the class being converted, and functions
1916 introduced by a using-declaration are considered to be
1917 members of the class that uses them.
1919 Since build_over_call ignores the ICS for the `this'
1920 parameter, we can just change the parm type. */
1921 if (ctype && is_this)
1923 parmtype = cp_build_qualified_type
1924 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
1925 parmtype = build_pointer_type (parmtype);
1928 /* Core issue 899: When [copy-]initializing a temporary to be bound
1929 to the first parameter of a copy constructor (12.8) called with
1930 a single argument in the context of direct-initialization,
1931 explicit conversion functions are also considered.
1933 So set LOOKUP_COPY_PARM to let reference_binding know that
1934 it's being called in that context. We generalize the above
1935 to handle move constructors and template constructors as well;
1936 the standardese should soon be updated similarly. */
1937 if (ctype && i == 0 && (len-skip == 1)
1938 && !(flags & LOOKUP_ONLYCONVERTING)
1939 && DECL_CONSTRUCTOR_P (fn)
1940 && parmtype != error_mark_node
1941 && (same_type_ignoring_top_level_qualifiers_p
1942 (non_reference (parmtype), ctype)))
1944 lflags |= LOOKUP_COPY_PARM;
1945 /* We allow user-defined conversions within init-lists, but
1946 not for the copy constructor. */
1947 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1948 lflags |= LOOKUP_NO_CONVERSION;
1951 lflags |= LOOKUP_ONLYCONVERTING;
1953 t = implicit_conversion (parmtype, argtype, arg,
1954 /*c_cast_p=*/false, lflags);
1959 t = build_identity_conv (argtype, arg);
1960 t->ellipsis_p = true;
1971 reason = arg_conversion_rejection (first_arg, i, argtype, to_type);
1978 reason = bad_arg_conversion_rejection (first_arg, i, argtype, to_type);
1983 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
1984 access_path, conversion_path, viable, reason);
1987 /* Create an overload candidate for the conversion function FN which will
1988 be invoked for expression OBJ, producing a pointer-to-function which
1989 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1990 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1991 passed on to implicit_conversion.
1993 Actually, we don't really care about FN; we care about the type it
1994 converts to. There may be multiple conversion functions that will
1995 convert to that type, and we rely on build_user_type_conversion_1 to
1996 choose the best one; so when we create our candidate, we record the type
1997 instead of the function. */
1999 static struct z_candidate *
2000 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
2001 tree first_arg, const VEC(tree,gc) *arglist,
2002 tree access_path, tree conversion_path)
2004 tree totype = TREE_TYPE (TREE_TYPE (fn));
2005 int i, len, viable, flags;
2006 tree parmlist, parmnode;
2008 struct rejection_reason *reason;
2010 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
2011 parmlist = TREE_TYPE (parmlist);
2012 parmlist = TYPE_ARG_TYPES (parmlist);
2014 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
2015 convs = alloc_conversions (len);
2016 parmnode = parmlist;
2018 flags = LOOKUP_IMPLICIT;
2021 /* Don't bother looking up the same type twice. */
2022 if (*candidates && (*candidates)->fn == totype)
2025 for (i = 0; i < len; ++i)
2027 tree arg, argtype, convert_type = NULL_TREE;
2032 else if (i == 1 && first_arg != NULL_TREE)
2035 arg = VEC_index (tree, arglist,
2036 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
2037 argtype = lvalue_type (arg);
2041 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
2043 convert_type = totype;
2045 else if (parmnode == void_list_node)
2049 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
2050 /*c_cast_p=*/false, flags);
2051 convert_type = TREE_VALUE (parmnode);
2055 t = build_identity_conv (argtype, arg);
2056 t->ellipsis_p = true;
2057 convert_type = argtype;
2067 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtype, convert_type);
2074 parmnode = TREE_CHAIN (parmnode);
2078 || ! sufficient_parms_p (parmnode))
2080 int remaining = remaining_arguments (parmnode);
2082 reason = arity_rejection (NULL_TREE, i + remaining, len);
2085 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
2086 access_path, conversion_path, viable, reason);
2090 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
2091 tree type1, tree type2, tree *args, tree *argtypes,
2099 struct rejection_reason *reason = NULL;
2104 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
2105 convs = alloc_conversions (num_convs);
2107 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2108 conversion ops are allowed. We handle that here by just checking for
2109 boolean_type_node because other operators don't ask for it. COND_EXPR
2110 also does contextual conversion to bool for the first operand, but we
2111 handle that in build_conditional_expr, and type1 here is operand 2. */
2112 if (type1 != boolean_type_node)
2113 flags |= LOOKUP_ONLYCONVERTING;
2115 for (i = 0; i < 2; ++i)
2120 t = implicit_conversion (types[i], argtypes[i], args[i],
2121 /*c_cast_p=*/false, flags);
2125 /* We need something for printing the candidate. */
2126 t = build_identity_conv (types[i], NULL_TREE);
2127 reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2132 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2137 /* For COND_EXPR we rearranged the arguments; undo that now. */
2140 convs[2] = convs[1];
2141 convs[1] = convs[0];
2142 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
2143 /*c_cast_p=*/false, flags);
2149 reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2],
2154 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
2156 /*access_path=*/NULL_TREE,
2157 /*conversion_path=*/NULL_TREE,
2162 is_complete (tree t)
2164 return COMPLETE_TYPE_P (complete_type (t));
2167 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2170 promoted_arithmetic_type_p (tree type)
2174 In this section, the term promoted integral type is used to refer
2175 to those integral types which are preserved by integral promotion
2176 (including e.g. int and long but excluding e.g. char).
2177 Similarly, the term promoted arithmetic type refers to promoted
2178 integral types plus floating types. */
2179 return ((CP_INTEGRAL_TYPE_P (type)
2180 && same_type_p (type_promotes_to (type), type))
2181 || TREE_CODE (type) == REAL_TYPE);
2184 /* Create any builtin operator overload candidates for the operator in
2185 question given the converted operand types TYPE1 and TYPE2. The other
2186 args are passed through from add_builtin_candidates to
2187 build_builtin_candidate.
2189 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2190 If CODE is requires candidates operands of the same type of the kind
2191 of which TYPE1 and TYPE2 are, we add both candidates
2192 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2195 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
2196 enum tree_code code2, tree fnname, tree type1,
2197 tree type2, tree *args, tree *argtypes, int flags)
2201 case POSTINCREMENT_EXPR:
2202 case POSTDECREMENT_EXPR:
2203 args[1] = integer_zero_node;
2204 type2 = integer_type_node;
2213 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2214 and VQ is either volatile or empty, there exist candidate operator
2215 functions of the form
2216 VQ T& operator++(VQ T&);
2217 T operator++(VQ T&, int);
2218 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2219 type other than bool, and VQ is either volatile or empty, there exist
2220 candidate operator functions of the form
2221 VQ T& operator--(VQ T&);
2222 T operator--(VQ T&, int);
2223 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2224 complete object type, and VQ is either volatile or empty, there exist
2225 candidate operator functions of the form
2226 T*VQ& operator++(T*VQ&);
2227 T*VQ& operator--(T*VQ&);
2228 T* operator++(T*VQ&, int);
2229 T* operator--(T*VQ&, int); */
2231 case POSTDECREMENT_EXPR:
2232 case PREDECREMENT_EXPR:
2233 if (TREE_CODE (type1) == BOOLEAN_TYPE)
2235 case POSTINCREMENT_EXPR:
2236 case PREINCREMENT_EXPR:
2237 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
2239 type1 = build_reference_type (type1);
2244 /* 7 For every cv-qualified or cv-unqualified object type T, there
2245 exist candidate operator functions of the form
2249 8 For every function type T, there exist candidate operator functions of
2251 T& operator*(T*); */
2254 if (TREE_CODE (type1) == POINTER_TYPE
2255 && !uses_template_parms (TREE_TYPE (type1))
2256 && (TYPE_PTROB_P (type1)
2257 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
2261 /* 9 For every type T, there exist candidate operator functions of the form
2264 10For every promoted arithmetic type T, there exist candidate operator
2265 functions of the form
2269 case UNARY_PLUS_EXPR: /* unary + */
2270 if (TREE_CODE (type1) == POINTER_TYPE)
2273 if (ARITHMETIC_TYPE_P (type1))
2277 /* 11For every promoted integral type T, there exist candidate operator
2278 functions of the form
2282 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2286 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2287 is the same type as C2 or is a derived class of C2, T is a complete
2288 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2289 there exist candidate operator functions of the form
2290 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2291 where CV12 is the union of CV1 and CV2. */
2294 if (TREE_CODE (type1) == POINTER_TYPE
2295 && TYPE_PTR_TO_MEMBER_P (type2))
2297 tree c1 = TREE_TYPE (type1);
2298 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2300 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2301 && (TYPE_PTRMEMFUNC_P (type2)
2302 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2307 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2308 didate operator functions of the form
2313 bool operator<(L, R);
2314 bool operator>(L, R);
2315 bool operator<=(L, R);
2316 bool operator>=(L, R);
2317 bool operator==(L, R);
2318 bool operator!=(L, R);
2319 where LR is the result of the usual arithmetic conversions between
2322 14For every pair of types T and I, where T is a cv-qualified or cv-
2323 unqualified complete object type and I is a promoted integral type,
2324 there exist candidate operator functions of the form
2325 T* operator+(T*, I);
2326 T& operator[](T*, I);
2327 T* operator-(T*, I);
2328 T* operator+(I, T*);
2329 T& operator[](I, T*);
2331 15For every T, where T is a pointer to complete object type, there exist
2332 candidate operator functions of the form112)
2333 ptrdiff_t operator-(T, T);
2335 16For every pointer or enumeration type T, there exist candidate operator
2336 functions of the form
2337 bool operator<(T, T);
2338 bool operator>(T, T);
2339 bool operator<=(T, T);
2340 bool operator>=(T, T);
2341 bool operator==(T, T);
2342 bool operator!=(T, T);
2344 17For every pointer to member type T, there exist candidate operator
2345 functions of the form
2346 bool operator==(T, T);
2347 bool operator!=(T, T); */
2350 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2352 if (TYPE_PTROB_P (type1)
2353 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2355 type2 = ptrdiff_type_node;
2359 case TRUNC_DIV_EXPR:
2360 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2366 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2367 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2369 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2374 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2386 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2388 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2390 if (TREE_CODE (type1) == ENUMERAL_TYPE
2391 && TREE_CODE (type2) == ENUMERAL_TYPE)
2393 if (TYPE_PTR_P (type1)
2394 && null_ptr_cst_p (args[1])
2395 && !uses_template_parms (type1))
2400 if (null_ptr_cst_p (args[0])
2401 && TYPE_PTR_P (type2)
2402 && !uses_template_parms (type2))
2410 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2413 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2415 type1 = ptrdiff_type_node;
2418 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2420 type2 = ptrdiff_type_node;
2425 /* 18For every pair of promoted integral types L and R, there exist candi-
2426 date operator functions of the form
2433 where LR is the result of the usual arithmetic conversions between
2436 case TRUNC_MOD_EXPR:
2442 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2446 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2447 type, VQ is either volatile or empty, and R is a promoted arithmetic
2448 type, there exist candidate operator functions of the form
2449 VQ L& operator=(VQ L&, R);
2450 VQ L& operator*=(VQ L&, R);
2451 VQ L& operator/=(VQ L&, R);
2452 VQ L& operator+=(VQ L&, R);
2453 VQ L& operator-=(VQ L&, R);
2455 20For every pair T, VQ), where T is any type and VQ is either volatile
2456 or empty, there exist candidate operator functions of the form
2457 T*VQ& operator=(T*VQ&, T*);
2459 21For every pair T, VQ), where T is a pointer to member type and VQ is
2460 either volatile or empty, there exist candidate operator functions of
2462 VQ T& operator=(VQ T&, T);
2464 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2465 unqualified complete object type, VQ is either volatile or empty, and
2466 I is a promoted integral type, there exist candidate operator func-
2468 T*VQ& operator+=(T*VQ&, I);
2469 T*VQ& operator-=(T*VQ&, I);
2471 23For every triple L, VQ, R), where L is an integral or enumeration
2472 type, VQ is either volatile or empty, and R is a promoted integral
2473 type, there exist candidate operator functions of the form
2475 VQ L& operator%=(VQ L&, R);
2476 VQ L& operator<<=(VQ L&, R);
2477 VQ L& operator>>=(VQ L&, R);
2478 VQ L& operator&=(VQ L&, R);
2479 VQ L& operator^=(VQ L&, R);
2480 VQ L& operator|=(VQ L&, R); */
2487 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2489 type2 = ptrdiff_type_node;
2493 case TRUNC_DIV_EXPR:
2494 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2498 case TRUNC_MOD_EXPR:
2504 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2509 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2511 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2512 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2513 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2514 || ((TYPE_PTRMEMFUNC_P (type1)
2515 || TREE_CODE (type1) == POINTER_TYPE)
2516 && null_ptr_cst_p (args[1])))
2526 type1 = build_reference_type (type1);
2532 For every pair of promoted arithmetic types L and R, there
2533 exist candidate operator functions of the form
2535 LR operator?(bool, L, R);
2537 where LR is the result of the usual arithmetic conversions
2538 between types L and R.
2540 For every type T, where T is a pointer or pointer-to-member
2541 type, there exist candidate operator functions of the form T
2542 operator?(bool, T, T); */
2544 if (promoted_arithmetic_type_p (type1)
2545 && promoted_arithmetic_type_p (type2))
2549 /* Otherwise, the types should be pointers. */
2550 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2551 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2554 /* We don't check that the two types are the same; the logic
2555 below will actually create two candidates; one in which both
2556 parameter types are TYPE1, and one in which both parameter
2562 if (ARITHMETIC_TYPE_P (type1))
2570 /* If we're dealing with two pointer types or two enumeral types,
2571 we need candidates for both of them. */
2572 if (type2 && !same_type_p (type1, type2)
2573 && TREE_CODE (type1) == TREE_CODE (type2)
2574 && (TREE_CODE (type1) == REFERENCE_TYPE
2575 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2576 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2577 || TYPE_PTRMEMFUNC_P (type1)
2578 || MAYBE_CLASS_TYPE_P (type1)
2579 || TREE_CODE (type1) == ENUMERAL_TYPE))
2581 build_builtin_candidate
2582 (candidates, fnname, type1, type1, args, argtypes, flags);
2583 build_builtin_candidate
2584 (candidates, fnname, type2, type2, args, argtypes, flags);
2588 build_builtin_candidate
2589 (candidates, fnname, type1, type2, args, argtypes, flags);
2593 type_decays_to (tree type)
2595 if (TREE_CODE (type) == ARRAY_TYPE)
2596 return build_pointer_type (TREE_TYPE (type));
2597 if (TREE_CODE (type) == FUNCTION_TYPE)
2598 return build_pointer_type (type);
2602 /* There are three conditions of builtin candidates:
2604 1) bool-taking candidates. These are the same regardless of the input.
2605 2) pointer-pair taking candidates. These are generated for each type
2606 one of the input types converts to.
2607 3) arithmetic candidates. According to the standard, we should generate
2608 all of these, but I'm trying not to...
2610 Here we generate a superset of the possible candidates for this particular
2611 case. That is a subset of the full set the standard defines, plus some
2612 other cases which the standard disallows. add_builtin_candidate will
2613 filter out the invalid set. */
2616 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2617 enum tree_code code2, tree fnname, tree *args,
2622 tree type, argtypes[3], t;
2623 /* TYPES[i] is the set of possible builtin-operator parameter types
2624 we will consider for the Ith argument. */
2625 VEC(tree,gc) *types[2];
2628 for (i = 0; i < 3; ++i)
2631 argtypes[i] = unlowered_expr_type (args[i]);
2633 argtypes[i] = NULL_TREE;
2638 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2639 and VQ is either volatile or empty, there exist candidate operator
2640 functions of the form
2641 VQ T& operator++(VQ T&); */
2643 case POSTINCREMENT_EXPR:
2644 case PREINCREMENT_EXPR:
2645 case POSTDECREMENT_EXPR:
2646 case PREDECREMENT_EXPR:
2651 /* 24There also exist candidate operator functions of the form
2652 bool operator!(bool);
2653 bool operator&&(bool, bool);
2654 bool operator||(bool, bool); */
2656 case TRUTH_NOT_EXPR:
2657 build_builtin_candidate
2658 (candidates, fnname, boolean_type_node,
2659 NULL_TREE, args, argtypes, flags);
2662 case TRUTH_ORIF_EXPR:
2663 case TRUTH_ANDIF_EXPR:
2664 build_builtin_candidate
2665 (candidates, fnname, boolean_type_node,
2666 boolean_type_node, args, argtypes, flags);
2688 types[0] = make_tree_vector ();
2689 types[1] = make_tree_vector ();
2691 for (i = 0; i < 2; ++i)
2695 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2699 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2702 convs = lookup_conversions (argtypes[i]);
2704 if (code == COND_EXPR)
2706 if (real_lvalue_p (args[i]))
2707 VEC_safe_push (tree, gc, types[i],
2708 build_reference_type (argtypes[i]));
2710 VEC_safe_push (tree, gc, types[i],
2711 TYPE_MAIN_VARIANT (argtypes[i]));
2717 for (; convs; convs = TREE_CHAIN (convs))
2719 type = TREE_TYPE (convs);
2722 && (TREE_CODE (type) != REFERENCE_TYPE
2723 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2726 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2727 VEC_safe_push (tree, gc, types[i], type);
2729 type = non_reference (type);
2730 if (i != 0 || ! ref1)
2732 type = cv_unqualified (type_decays_to (type));
2733 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2734 VEC_safe_push (tree, gc, types[i], type);
2735 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2736 type = type_promotes_to (type);
2739 if (! vec_member (type, types[i]))
2740 VEC_safe_push (tree, gc, types[i], type);
2745 if (code == COND_EXPR && real_lvalue_p (args[i]))
2746 VEC_safe_push (tree, gc, types[i],
2747 build_reference_type (argtypes[i]));
2748 type = non_reference (argtypes[i]);
2749 if (i != 0 || ! ref1)
2751 type = cv_unqualified (type_decays_to (type));
2752 if (enum_p && UNSCOPED_ENUM_P (type))
2753 VEC_safe_push (tree, gc, types[i], type);
2754 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2755 type = type_promotes_to (type);
2757 VEC_safe_push (tree, gc, types[i], type);
2761 /* Run through the possible parameter types of both arguments,
2762 creating candidates with those parameter types. */
2763 FOR_EACH_VEC_ELT_REVERSE (tree, types[0], ix, t)
2768 if (!VEC_empty (tree, types[1]))
2769 FOR_EACH_VEC_ELT_REVERSE (tree, types[1], jx, u)
2770 add_builtin_candidate
2771 (candidates, code, code2, fnname, t,
2772 u, args, argtypes, flags);
2774 add_builtin_candidate
2775 (candidates, code, code2, fnname, t,
2776 NULL_TREE, args, argtypes, flags);
2779 release_tree_vector (types[0]);
2780 release_tree_vector (types[1]);
2784 /* If TMPL can be successfully instantiated as indicated by
2785 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2787 TMPL is the template. EXPLICIT_TARGS are any explicit template
2788 arguments. ARGLIST is the arguments provided at the call-site.
2789 This does not change ARGLIST. The RETURN_TYPE is the desired type
2790 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2791 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2792 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2794 static struct z_candidate*
2795 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2796 tree ctype, tree explicit_targs, tree first_arg,
2797 const VEC(tree,gc) *arglist, tree return_type,
2798 tree access_path, tree conversion_path,
2799 int flags, tree obj, unification_kind_t strict)
2801 int ntparms = DECL_NTPARMS (tmpl);
2802 tree targs = make_tree_vec (ntparms);
2803 unsigned int len = VEC_length (tree, arglist);
2804 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2805 unsigned int skip_without_in_chrg = 0;
2806 tree first_arg_without_in_chrg = first_arg;
2807 tree *args_without_in_chrg;
2808 unsigned int nargs_without_in_chrg;
2809 unsigned int ia, ix;
2811 struct z_candidate *cand;
2814 struct rejection_reason *reason = NULL;
2817 /* We don't do deduction on the in-charge parameter, the VTT
2818 parameter or 'this'. */
2819 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2821 if (first_arg_without_in_chrg != NULL_TREE)
2822 first_arg_without_in_chrg = NULL_TREE;
2824 ++skip_without_in_chrg;
2827 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2828 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2829 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2831 if (first_arg_without_in_chrg != NULL_TREE)
2832 first_arg_without_in_chrg = NULL_TREE;
2834 ++skip_without_in_chrg;
2837 if (len < skip_without_in_chrg)
2840 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2841 + (len - skip_without_in_chrg));
2842 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2844 if (first_arg_without_in_chrg != NULL_TREE)
2846 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2849 for (ix = skip_without_in_chrg;
2850 VEC_iterate (tree, arglist, ix, arg);
2853 args_without_in_chrg[ia] = arg;
2856 gcc_assert (ia == nargs_without_in_chrg);
2858 errs = errorcount+sorrycount;
2859 i = fn_type_unification (tmpl, explicit_targs, targs,
2860 args_without_in_chrg,
2861 nargs_without_in_chrg,
2862 return_type, strict, flags, false);
2866 /* Don't repeat unification later if it already resulted in errors. */
2867 if (errorcount+sorrycount == errs)
2868 reason = template_unification_rejection (tmpl, explicit_targs,
2869 targs, args_without_in_chrg,
2870 nargs_without_in_chrg,
2871 return_type, strict, flags);
2873 reason = template_unification_error_rejection ();
2877 fn = instantiate_template (tmpl, targs, tf_none);
2878 if (fn == error_mark_node)
2880 reason = template_instantiation_rejection (tmpl, targs);
2886 A member function template is never instantiated to perform the
2887 copy of a class object to an object of its class type.
2889 It's a little unclear what this means; the standard explicitly
2890 does allow a template to be used to copy a class. For example,
2895 template <class T> A(const T&);
2898 void g () { A a (f ()); }
2900 the member template will be used to make the copy. The section
2901 quoted above appears in the paragraph that forbids constructors
2902 whose only parameter is (a possibly cv-qualified variant of) the
2903 class type, and a logical interpretation is that the intent was
2904 to forbid the instantiation of member templates which would then
2906 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2908 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2909 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2912 reason = invalid_copy_with_fn_template_rejection ();
2917 if (obj != NULL_TREE)
2918 /* Aha, this is a conversion function. */
2919 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2920 access_path, conversion_path);
2922 cand = add_function_candidate (candidates, fn, ctype,
2923 first_arg, arglist, access_path,
2924 conversion_path, flags);
2925 if (DECL_TI_TEMPLATE (fn) != tmpl)
2926 /* This situation can occur if a member template of a template
2927 class is specialized. Then, instantiate_template might return
2928 an instantiation of the specialization, in which case the
2929 DECL_TI_TEMPLATE field will point at the original
2930 specialization. For example:
2932 template <class T> struct S { template <class U> void f(U);
2933 template <> void f(int) {}; };
2937 Here, TMPL will be template <class U> S<double>::f(U).
2938 And, instantiate template will give us the specialization
2939 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2940 for this will point at template <class T> template <> S<T>::f(int),
2941 so that we can find the definition. For the purposes of
2942 overload resolution, however, we want the original TMPL. */
2943 cand->template_decl = build_template_info (tmpl, targs);
2945 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2946 cand->explicit_targs = explicit_targs;
2950 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
2951 access_path, conversion_path, 0, reason);
2955 static struct z_candidate *
2956 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2957 tree explicit_targs, tree first_arg,
2958 const VEC(tree,gc) *arglist, tree return_type,
2959 tree access_path, tree conversion_path, int flags,
2960 unification_kind_t strict)
2963 add_template_candidate_real (candidates, tmpl, ctype,
2964 explicit_targs, first_arg, arglist,
2965 return_type, access_path, conversion_path,
2966 flags, NULL_TREE, strict);
2970 static struct z_candidate *
2971 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2972 tree obj, tree first_arg,
2973 const VEC(tree,gc) *arglist,
2974 tree return_type, tree access_path,
2975 tree conversion_path)
2978 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2979 first_arg, arglist, return_type, access_path,
2980 conversion_path, 0, obj, DEDUCE_CONV);
2983 /* The CANDS are the set of candidates that were considered for
2984 overload resolution. Return the set of viable candidates, or CANDS
2985 if none are viable. If any of the candidates were viable, set
2986 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
2987 considered viable only if it is strictly viable. */
2989 static struct z_candidate*
2990 splice_viable (struct z_candidate *cands,
2994 struct z_candidate *viable;
2995 struct z_candidate **last_viable;
2996 struct z_candidate **cand;
2998 /* Be strict inside templates, since build_over_call won't actually
2999 do the conversions to get pedwarns. */
3000 if (processing_template_decl)
3004 last_viable = &viable;
3005 *any_viable_p = false;
3010 struct z_candidate *c = *cand;
3011 if (strict_p ? c->viable == 1 : c->viable)
3016 last_viable = &c->next;
3017 *any_viable_p = true;
3023 return viable ? viable : cands;
3027 any_strictly_viable (struct z_candidate *cands)
3029 for (; cands; cands = cands->next)
3030 if (cands->viable == 1)
3035 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3036 words, it is about to become the "this" pointer for a member
3037 function call. Take the address of the object. */
3040 build_this (tree obj)
3042 /* In a template, we are only concerned about the type of the
3043 expression, so we can take a shortcut. */
3044 if (processing_template_decl)
3045 return build_address (obj);
3047 return cp_build_addr_expr (obj, tf_warning_or_error);
3050 /* Returns true iff functions are equivalent. Equivalent functions are
3051 not '==' only if one is a function-local extern function or if
3052 both are extern "C". */
3055 equal_functions (tree fn1, tree fn2)
3057 if (TREE_CODE (fn1) != TREE_CODE (fn2))
3059 if (TREE_CODE (fn1) == TEMPLATE_DECL)
3061 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
3062 || DECL_EXTERN_C_FUNCTION_P (fn1))
3063 return decls_match (fn1, fn2);
3067 /* Print information about a candidate being rejected due to INFO. */
3070 print_conversion_rejection (location_t loc, struct conversion_info *info)
3072 if (info->n_arg == -1)
3073 /* Conversion of implicit `this' argument failed. */
3074 inform (loc, " no known conversion for implicit "
3075 "%<this%> parameter from %qT to %qT",
3076 info->from_type, info->to_type);
3078 inform (loc, " no known conversion for argument %d from %qT to %qT",
3079 info->n_arg+1, info->from_type, info->to_type);
3082 /* Print information about a candidate with WANT parameters and we found
3086 print_arity_information (location_t loc, unsigned int have, unsigned int want)
3088 inform_n (loc, want,
3089 " candidate expects %d argument, %d provided",
3090 " candidate expects %d arguments, %d provided",
3094 /* Print information about one overload candidate CANDIDATE. MSGSTR
3095 is the text to print before the candidate itself.
3097 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3098 to have been run through gettext by the caller. This wart makes
3099 life simpler in print_z_candidates and for the translators. */
3102 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
3104 const char *msg = (msgstr == NULL
3106 : ACONCAT ((msgstr, " ", NULL)));
3107 location_t loc = location_of (candidate->fn);
3109 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
3111 if (candidate->num_convs == 3)
3112 inform (input_location, "%s%D(%T, %T, %T) <built-in>", msg, candidate->fn,
3113 candidate->convs[0]->type,
3114 candidate->convs[1]->type,
3115 candidate->convs[2]->type);
3116 else if (candidate->num_convs == 2)
3117 inform (input_location, "%s%D(%T, %T) <built-in>", msg, candidate->fn,
3118 candidate->convs[0]->type,
3119 candidate->convs[1]->type);
3121 inform (input_location, "%s%D(%T) <built-in>", msg, candidate->fn,
3122 candidate->convs[0]->type);
3124 else if (TYPE_P (candidate->fn))
3125 inform (input_location, "%s%T <conversion>", msg, candidate->fn);
3126 else if (candidate->viable == -1)
3127 inform (loc, "%s%#D <near match>", msg, candidate->fn);
3128 else if (DECL_DELETED_FN (STRIP_TEMPLATE (candidate->fn)))
3129 inform (loc, "%s%#D <deleted>", msg, candidate->fn);
3131 inform (loc, "%s%#D", msg, candidate->fn);
3132 /* Give the user some information about why this candidate failed. */
3133 if (candidate->reason != NULL)
3135 struct rejection_reason *r = candidate->reason;
3140 print_arity_information (loc, r->u.arity.actual,
3141 r->u.arity.expected);
3143 case rr_arg_conversion:
3144 print_conversion_rejection (loc, &r->u.conversion);
3146 case rr_bad_arg_conversion:
3147 print_conversion_rejection (loc, &r->u.bad_conversion);
3149 case rr_explicit_conversion:
3150 inform (loc, " return type %qT of explicit conversion function "
3151 "cannot be converted to %qT with a qualification "
3152 "conversion", r->u.conversion.from_type,
3153 r->u.conversion.to_type);
3155 case rr_template_conversion:
3156 inform (loc, " conversion from return type %qT of template "
3157 "conversion function specialization to %qT is not an "
3158 "exact match", r->u.conversion.from_type,
3159 r->u.conversion.to_type);
3161 case rr_template_unification:
3162 /* We use template_unification_error_rejection if unification caused
3163 actual non-SFINAE errors, in which case we don't need to repeat
3165 if (r->u.template_unification.tmpl == NULL_TREE)
3167 inform (loc, " substitution of deduced template arguments "
3168 "resulted in errors seen above");
3171 /* Re-run template unification with diagnostics. */
3172 inform (loc, " template argument deduction/substitution failed:");
3173 fn_type_unification (r->u.template_unification.tmpl,
3174 r->u.template_unification.explicit_targs,
3175 r->u.template_unification.targs,
3176 r->u.template_unification.args,
3177 r->u.template_unification.nargs,
3178 r->u.template_unification.return_type,
3179 r->u.template_unification.strict,
3180 r->u.template_unification.flags,
3183 case rr_template_instantiation:
3184 /* Re-run template instantiation with diagnostics. */
3185 instantiate_template (r->u.template_instantiation.tmpl,
3186 r->u.template_instantiation.targs,
3187 tf_warning_or_error);
3189 case rr_invalid_copy:
3191 " a constructor taking a single argument of its own "
3192 "class type is invalid");
3196 /* This candidate didn't have any issues or we failed to
3197 handle a particular code. Either way... */
3204 print_z_candidates (location_t loc, struct z_candidate *candidates)
3206 struct z_candidate *cand1;
3207 struct z_candidate **cand2;
3213 /* Remove non-viable deleted candidates. */
3215 for (cand2 = &cand1; *cand2; )
3217 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
3218 && !(*cand2)->viable
3219 && DECL_DELETED_FN ((*cand2)->fn))
3220 *cand2 = (*cand2)->next;
3222 cand2 = &(*cand2)->next;
3224 /* ...if there are any non-deleted ones. */
3228 /* There may be duplicates in the set of candidates. We put off
3229 checking this condition as long as possible, since we have no way
3230 to eliminate duplicates from a set of functions in less than n^2
3231 time. Now we are about to emit an error message, so it is more
3232 permissible to go slowly. */
3233 for (cand1 = candidates; cand1; cand1 = cand1->next)
3235 tree fn = cand1->fn;
3236 /* Skip builtin candidates and conversion functions. */
3239 cand2 = &cand1->next;
3242 if (DECL_P ((*cand2)->fn)
3243 && equal_functions (fn, (*cand2)->fn))
3244 *cand2 = (*cand2)->next;
3246 cand2 = &(*cand2)->next;
3250 for (n_candidates = 0, cand1 = candidates; cand1; cand1 = cand1->next)
3253 inform_n (loc, n_candidates, "candidate is:", "candidates are:");
3254 for (; candidates; candidates = candidates->next)
3255 print_z_candidate (NULL, candidates);
3258 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3259 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3260 the result of the conversion function to convert it to the final
3261 desired type. Merge the two sequences into a single sequence,
3262 and return the merged sequence. */
3265 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
3268 bool bad = user_seq->bad_p;
3270 gcc_assert (user_seq->kind == ck_user);
3272 /* Find the end of the second conversion sequence. */
3273 for (t = &std_seq; (*t)->kind != ck_identity; t = &((*t)->u.next))
3275 /* The entire sequence is a user-conversion sequence. */
3276 (*t)->user_conv_p = true;
3281 /* Replace the identity conversion with the user conversion
3288 /* Handle overload resolution for initializing an object of class type from
3289 an initializer list. First we look for a suitable constructor that
3290 takes a std::initializer_list; if we don't find one, we then look for a
3291 non-list constructor.
3293 Parameters are as for add_candidates, except that the arguments are in
3294 the form of a CONSTRUCTOR (the initializer list) rather than a VEC, and
3295 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3298 add_list_candidates (tree fns, tree first_arg,
3299 tree init_list, tree totype,
3300 tree explicit_targs, bool template_only,
3301 tree conversion_path, tree access_path,
3303 struct z_candidate **candidates)
3307 gcc_assert (*candidates == NULL);
3309 /* For list-initialization we consider explicit constructors, but
3310 give an error if one is selected. */
3311 flags &= ~LOOKUP_ONLYCONVERTING;
3312 /* And we don't allow narrowing conversions. We also use this flag to
3313 avoid the copy constructor call for copy-list-initialization. */
3314 flags |= LOOKUP_NO_NARROWING;
3316 /* Always use the default constructor if the list is empty (DR 990). */
3317 if (CONSTRUCTOR_NELTS (init_list) == 0
3318 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
3320 /* If the class has a list ctor, try passing the list as a single
3321 argument first, but only consider list ctors. */
3322 else if (TYPE_HAS_LIST_CTOR (totype))
3324 flags |= LOOKUP_LIST_ONLY;
3325 args = make_tree_vector_single (init_list);
3326 add_candidates (fns, first_arg, args, NULL_TREE,
3327 explicit_targs, template_only, conversion_path,
3328 access_path, flags, candidates);
3329 if (any_strictly_viable (*candidates))
3333 args = ctor_to_vec (init_list);
3335 /* We aren't looking for list-ctors anymore. */
3336 flags &= ~LOOKUP_LIST_ONLY;
3337 /* We allow more user-defined conversions within an init-list. */
3338 flags &= ~LOOKUP_NO_CONVERSION;
3339 /* But not for the copy ctor. */
3340 flags |= LOOKUP_NO_COPY_CTOR_CONVERSION;
3342 add_candidates (fns, first_arg, args, NULL_TREE,
3343 explicit_targs, template_only, conversion_path,
3344 access_path, flags, candidates);
3347 /* Returns the best overload candidate to perform the requested
3348 conversion. This function is used for three the overloading situations
3349 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3350 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3351 per [dcl.init.ref], so we ignore temporary bindings. */
3353 static struct z_candidate *
3354 build_user_type_conversion_1 (tree totype, tree expr, int flags)
3356 struct z_candidate *candidates, *cand;
3357 tree fromtype = TREE_TYPE (expr);
3358 tree ctors = NULL_TREE;
3359 tree conv_fns = NULL_TREE;
3360 conversion *conv = NULL;
3361 tree first_arg = NULL_TREE;
3362 VEC(tree,gc) *args = NULL;
3366 /* We represent conversion within a hierarchy using RVALUE_CONV and
3367 BASE_CONV, as specified by [over.best.ics]; these become plain
3368 constructor calls, as specified in [dcl.init]. */
3369 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
3370 || !DERIVED_FROM_P (totype, fromtype));
3372 if (MAYBE_CLASS_TYPE_P (totype))
3373 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3374 creating a garbage BASELINK; constructors can't be inherited. */
3375 ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
3377 if (MAYBE_CLASS_TYPE_P (fromtype))
3379 tree to_nonref = non_reference (totype);
3380 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
3381 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
3382 && DERIVED_FROM_P (to_nonref, fromtype)))
3384 /* [class.conv.fct] A conversion function is never used to
3385 convert a (possibly cv-qualified) object to the (possibly
3386 cv-qualified) same object type (or a reference to it), to a
3387 (possibly cv-qualified) base class of that type (or a
3388 reference to it)... */
3391 conv_fns = lookup_conversions (fromtype);
3395 flags |= LOOKUP_NO_CONVERSION;
3396 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3397 flags |= LOOKUP_NO_NARROWING;
3399 /* It's OK to bind a temporary for converting constructor arguments, but
3400 not in converting the return value of a conversion operator. */
3401 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
3402 flags &= ~LOOKUP_NO_TEMP_BIND;
3406 int ctorflags = flags;
3408 first_arg = build_int_cst (build_pointer_type (totype), 0);
3410 /* We should never try to call the abstract or base constructor
3412 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3413 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3415 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3417 /* List-initialization. */
3418 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3419 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3420 ctorflags, &candidates);
3424 args = make_tree_vector_single (expr);
3425 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3426 TYPE_BINFO (totype), TYPE_BINFO (totype),
3427 ctorflags, &candidates);
3430 for (cand = candidates; cand; cand = cand->next)
3432 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3434 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3435 set, then this is copy-initialization. In that case, "The
3436 result of the call is then used to direct-initialize the
3437 object that is the destination of the copy-initialization."
3440 We represent this in the conversion sequence with an
3441 rvalue conversion, which means a constructor call. */
3442 if (TREE_CODE (totype) != REFERENCE_TYPE
3443 && !(convflags & LOOKUP_NO_TEMP_BIND))
3445 = build_conv (ck_rvalue, totype, cand->second_conv);
3450 first_arg = build_this (expr);
3452 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3454 tree conversion_path = TREE_PURPOSE (conv_fns);
3455 struct z_candidate *old_candidates;
3457 /* If we are called to convert to a reference type, we are trying to
3458 find a direct binding, so don't even consider temporaries. If
3459 we don't find a direct binding, the caller will try again to
3460 look for a temporary binding. */
3461 if (TREE_CODE (totype) == REFERENCE_TYPE)
3462 convflags |= LOOKUP_NO_TEMP_BIND;
3464 old_candidates = candidates;
3465 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3467 conversion_path, TYPE_BINFO (fromtype),
3468 flags, &candidates);
3470 for (cand = candidates; cand != old_candidates; cand = cand->next)
3472 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3474 = implicit_conversion (totype,
3477 /*c_cast_p=*/false, convflags);
3479 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3480 copy-initialization. In that case, "The result of the
3481 call is then used to direct-initialize the object that is
3482 the destination of the copy-initialization." [dcl.init]
3484 We represent this in the conversion sequence with an
3485 rvalue conversion, which means a constructor call. But
3486 don't add a second rvalue conversion if there's already
3487 one there. Which there really shouldn't be, but it's
3488 harmless since we'd add it here anyway. */
3489 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3490 && !(convflags & LOOKUP_NO_TEMP_BIND))
3491 ics = build_conv (ck_rvalue, totype, ics);
3493 cand->second_conv = ics;
3498 cand->reason = arg_conversion_rejection (NULL_TREE, -1,
3501 else if (DECL_NONCONVERTING_P (cand->fn)
3502 && ics->rank > cr_exact)
3504 /* 13.3.1.5: For direct-initialization, those explicit
3505 conversion functions that are not hidden within S and
3506 yield type T or a type that can be converted to type T
3507 with a qualification conversion (4.4) are also candidate
3509 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3510 I've raised this issue with the committee. --jason 9/2011 */
3512 cand->reason = explicit_conversion_rejection (rettype, totype);
3514 else if (cand->viable == 1 && ics->bad_p)
3518 = bad_arg_conversion_rejection (NULL_TREE, -1,
3521 else if (primary_template_instantiation_p (cand->fn)
3522 && ics->rank > cr_exact)
3524 /* 13.3.3.1.2: If the user-defined conversion is specified by
3525 a specialization of a conversion function template, the
3526 second standard conversion sequence shall have exact match
3529 cand->reason = template_conversion_rejection (rettype, totype);
3534 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3538 release_tree_vector (args);
3542 cand = tourney (candidates);
3545 if (flags & LOOKUP_COMPLAIN)
3547 error ("conversion from %qT to %qT is ambiguous",
3549 print_z_candidates (location_of (expr), candidates);
3552 cand = candidates; /* any one will do */
3553 cand->second_conv = build_ambiguous_conv (totype, expr);
3554 cand->second_conv->user_conv_p = true;
3555 if (!any_strictly_viable (candidates))
3556 cand->second_conv->bad_p = true;
3557 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3558 ambiguous conversion is no worse than another user-defined
3564 /* Build the user conversion sequence. */
3567 (DECL_CONSTRUCTOR_P (cand->fn)
3568 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3569 build_identity_conv (TREE_TYPE (expr), expr));
3571 if (cand->viable == -1)
3574 /* Remember that this was a list-initialization. */
3575 if (flags & LOOKUP_NO_NARROWING)
3576 conv->check_narrowing = true;
3578 /* Combine it with the second conversion sequence. */
3579 cand->second_conv = merge_conversion_sequences (conv,
3585 /* Wrapper for above. */
3588 build_user_type_conversion (tree totype, tree expr, int flags)
3590 struct z_candidate *cand;
3593 bool subtime = timevar_cond_start (TV_OVERLOAD);
3594 cand = build_user_type_conversion_1 (totype, expr, flags);
3598 if (cand->second_conv->kind == ck_ambig)
3599 ret = error_mark_node;
3602 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3603 ret = convert_from_reference (expr);
3609 timevar_cond_stop (TV_OVERLOAD, subtime);
3613 /* Subroutine of convert_nontype_argument.
3615 EXPR is an argument for a template non-type parameter of integral or
3616 enumeration type. Do any necessary conversions (that are permitted for
3617 non-type arguments) to convert it to the parameter type.
3619 If conversion is successful, returns the converted expression;
3620 otherwise, returns error_mark_node. */
3623 build_integral_nontype_arg_conv (tree type, tree expr, tsubst_flags_t complain)
3629 if (error_operand_p (expr))
3630 return error_mark_node;
3632 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
3634 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3635 p = conversion_obstack_alloc (0);
3637 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
3641 /* for a non-type template-parameter of integral or
3642 enumeration type, integral promotions (4.5) and integral
3643 conversions (4.7) are applied. */
3644 /* It should be sufficient to check the outermost conversion step, since
3645 there are no qualification conversions to integer type. */
3649 /* A conversion function is OK. If it isn't constexpr, we'll
3650 complain later that the argument isn't constant. */
3652 /* The lvalue-to-rvalue conversion is OK. */
3658 t = conv->u.next->type;
3659 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t))
3662 if (complain & tf_error)
3663 error ("conversion from %qT to %qT not considered for "
3664 "non-type template argument", t, type);
3665 /* and fall through. */
3673 expr = convert_like (conv, expr, complain);
3675 expr = error_mark_node;
3677 /* Free all the conversions we allocated. */
3678 obstack_free (&conversion_obstack, p);
3683 /* Do any initial processing on the arguments to a function call. */
3685 static VEC(tree,gc) *
3686 resolve_args (VEC(tree,gc) *args, tsubst_flags_t complain)
3691 FOR_EACH_VEC_ELT (tree, args, ix, arg)
3693 if (error_operand_p (arg))
3695 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3697 if (complain & tf_error)
3698 error ("invalid use of void expression");
3701 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3707 /* Perform overload resolution on FN, which is called with the ARGS.
3709 Return the candidate function selected by overload resolution, or
3710 NULL if the event that overload resolution failed. In the case
3711 that overload resolution fails, *CANDIDATES will be the set of
3712 candidates considered, and ANY_VIABLE_P will be set to true or
3713 false to indicate whether or not any of the candidates were
3716 The ARGS should already have gone through RESOLVE_ARGS before this
3717 function is called. */
3719 static struct z_candidate *
3720 perform_overload_resolution (tree fn,
3721 const VEC(tree,gc) *args,
3722 struct z_candidate **candidates,
3725 struct z_candidate *cand;
3726 tree explicit_targs;
3729 bool subtime = timevar_cond_start (TV_OVERLOAD);
3731 explicit_targs = NULL_TREE;
3735 *any_viable_p = true;
3738 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3739 || TREE_CODE (fn) == TEMPLATE_DECL
3740 || TREE_CODE (fn) == OVERLOAD
3741 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3743 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3745 explicit_targs = TREE_OPERAND (fn, 1);
3746 fn = TREE_OPERAND (fn, 0);
3750 /* Add the various candidate functions. */
3751 add_candidates (fn, NULL_TREE, args, NULL_TREE,
3752 explicit_targs, template_only,
3753 /*conversion_path=*/NULL_TREE,
3754 /*access_path=*/NULL_TREE,
3758 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3760 cand = tourney (*candidates);
3764 timevar_cond_stop (TV_OVERLOAD, subtime);
3768 /* Print an error message about being unable to build a call to FN with
3769 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
3770 be located; CANDIDATES is a possibly empty list of such
3774 print_error_for_call_failure (tree fn, VEC(tree,gc) *args, bool any_viable_p,
3775 struct z_candidate *candidates)
3777 tree name = DECL_NAME (OVL_CURRENT (fn));
3778 location_t loc = location_of (name);
3781 error_at (loc, "no matching function for call to %<%D(%A)%>",
3782 name, build_tree_list_vec (args));
3784 error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous",
3785 name, build_tree_list_vec (args));
3787 print_z_candidates (loc, candidates);
3790 /* Return an expression for a call to FN (a namespace-scope function,
3791 or a static member function) with the ARGS. This may change
3795 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3796 tsubst_flags_t complain)
3798 struct z_candidate *candidates, *cand;
3803 if (args != NULL && *args != NULL)
3805 *args = resolve_args (*args, complain);
3807 return error_mark_node;
3810 /* If this function was found without using argument dependent
3811 lookup, then we want to ignore any undeclared friend
3817 fn = remove_hidden_names (fn);
3820 if (complain & tf_error)
3821 print_error_for_call_failure (orig_fn, *args, false, NULL);
3822 return error_mark_node;
3826 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3827 p = conversion_obstack_alloc (0);
3829 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3833 if (complain & tf_error)
3835 if (!any_viable_p && candidates && ! candidates->next
3836 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
3837 return cp_build_function_call_vec (candidates->fn, args, complain);
3838 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3839 fn = TREE_OPERAND (fn, 0);
3840 print_error_for_call_failure (fn, *args, any_viable_p, candidates);
3842 result = error_mark_node;
3846 int flags = LOOKUP_NORMAL;
3847 /* If fn is template_id_expr, the call has explicit template arguments
3848 (e.g. func<int>(5)), communicate this info to build_over_call
3849 through flags so that later we can use it to decide whether to warn
3850 about peculiar null pointer conversion. */
3851 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3852 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
3853 result = build_over_call (cand, flags, complain);
3856 /* Free all the conversions we allocated. */
3857 obstack_free (&conversion_obstack, p);
3862 /* Build a call to a global operator new. FNNAME is the name of the
3863 operator (either "operator new" or "operator new[]") and ARGS are
3864 the arguments provided. This may change ARGS. *SIZE points to the
3865 total number of bytes required by the allocation, and is updated if
3866 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3867 be used. If this function determines that no cookie should be
3868 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3869 non-NULL, it will be set, upon return, to the allocation function
3873 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3874 tree *size, tree *cookie_size,
3878 struct z_candidate *candidates;
3879 struct z_candidate *cand;
3884 VEC_safe_insert (tree, gc, *args, 0, *size);
3885 *args = resolve_args (*args, tf_warning_or_error);
3887 return error_mark_node;
3893 If this lookup fails to find the name, or if the allocated type
3894 is not a class type, the allocation function's name is looked
3895 up in the global scope.
3897 we disregard block-scope declarations of "operator new". */
3898 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3900 /* Figure out what function is being called. */
3901 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3903 /* If no suitable function could be found, issue an error message
3907 print_error_for_call_failure (fns, *args, any_viable_p, candidates);
3908 return error_mark_node;
3911 /* If a cookie is required, add some extra space. Whether
3912 or not a cookie is required cannot be determined until
3913 after we know which function was called. */
3916 bool use_cookie = true;
3917 if (!abi_version_at_least (2))
3919 /* In G++ 3.2, the check was implemented incorrectly; it
3920 looked at the placement expression, rather than the
3921 type of the function. */
3922 if (VEC_length (tree, *args) == 2
3923 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3931 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3932 /* Skip the size_t parameter. */
3933 arg_types = TREE_CHAIN (arg_types);
3934 /* Check the remaining parameters (if any). */
3936 && TREE_CHAIN (arg_types) == void_list_node
3937 && same_type_p (TREE_VALUE (arg_types),
3941 /* If we need a cookie, adjust the number of bytes allocated. */
3944 /* Update the total size. */
3945 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3946 /* Update the argument list to reflect the adjusted size. */
3947 VEC_replace (tree, *args, 0, *size);
3950 *cookie_size = NULL_TREE;
3953 /* Tell our caller which function we decided to call. */
3957 /* Build the CALL_EXPR. */
3958 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3961 /* Build a new call to operator(). This may change ARGS. */
3964 build_op_call_1 (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3966 struct z_candidate *candidates = 0, *cand;
3967 tree fns, convs, first_mem_arg = NULL_TREE;
3968 tree type = TREE_TYPE (obj);
3970 tree result = NULL_TREE;
3973 if (error_operand_p (obj))
3974 return error_mark_node;
3976 obj = prep_operand (obj);
3978 if (TYPE_PTRMEMFUNC_P (type))
3980 if (complain & tf_error)
3981 /* It's no good looking for an overloaded operator() on a
3982 pointer-to-member-function. */
3983 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3984 return error_mark_node;
3987 if (TYPE_BINFO (type))
3989 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3990 if (fns == error_mark_node)
3991 return error_mark_node;
3996 if (args != NULL && *args != NULL)
3998 *args = resolve_args (*args, complain);
4000 return error_mark_node;
4003 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4004 p = conversion_obstack_alloc (0);
4008 first_mem_arg = build_this (obj);
4010 add_candidates (BASELINK_FUNCTIONS (fns),
4011 first_mem_arg, *args, NULL_TREE,
4013 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
4014 LOOKUP_NORMAL, &candidates);
4017 convs = lookup_conversions (type);
4019 for (; convs; convs = TREE_CHAIN (convs))
4021 tree fns = TREE_VALUE (convs);
4022 tree totype = TREE_TYPE (convs);
4024 if ((TREE_CODE (totype) == POINTER_TYPE
4025 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
4026 || (TREE_CODE (totype) == REFERENCE_TYPE
4027 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
4028 || (TREE_CODE (totype) == REFERENCE_TYPE
4029 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
4030 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
4031 for (; fns; fns = OVL_NEXT (fns))
4033 tree fn = OVL_CURRENT (fns);
4035 if (DECL_NONCONVERTING_P (fn))
4038 if (TREE_CODE (fn) == TEMPLATE_DECL)
4039 add_template_conv_candidate
4040 (&candidates, fn, obj, NULL_TREE, *args, totype,
4041 /*access_path=*/NULL_TREE,
4042 /*conversion_path=*/NULL_TREE);
4044 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
4045 *args, /*conversion_path=*/NULL_TREE,
4046 /*access_path=*/NULL_TREE);
4050 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4053 if (complain & tf_error)
4055 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
4056 build_tree_list_vec (*args));
4057 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4059 result = error_mark_node;
4063 cand = tourney (candidates);
4066 if (complain & tf_error)
4068 error ("call of %<(%T) (%A)%> is ambiguous",
4069 TREE_TYPE (obj), build_tree_list_vec (*args));
4070 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4072 result = error_mark_node;
4074 /* Since cand->fn will be a type, not a function, for a conversion
4075 function, we must be careful not to unconditionally look at
4077 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
4078 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
4079 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4082 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
4084 obj = convert_from_reference (obj);
4085 result = cp_build_function_call_vec (obj, args, complain);
4089 /* Free all the conversions we allocated. */
4090 obstack_free (&conversion_obstack, p);
4095 /* Wrapper for above. */
4098 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
4101 bool subtime = timevar_cond_start (TV_OVERLOAD);
4102 ret = build_op_call_1 (obj, args, complain);
4103 timevar_cond_stop (TV_OVERLOAD, subtime);
4108 op_error (enum tree_code code, enum tree_code code2,
4109 tree arg1, tree arg2, tree arg3, bool match)
4113 if (code == MODIFY_EXPR)
4114 opname = assignment_operator_name_info[code2].name;
4116 opname = operator_name_info[code].name;
4122 error ("ambiguous overload for ternary %<operator?:%> "
4123 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4125 error ("no match for ternary %<operator?:%> "
4126 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4129 case POSTINCREMENT_EXPR:
4130 case POSTDECREMENT_EXPR:
4132 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
4133 opname, arg1, opname);
4135 error ("no match for %<operator%s%> in %<%E%s%>",
4136 opname, arg1, opname);
4141 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
4144 error ("no match for %<operator[]%> in %<%E[%E]%>",
4151 error ("ambiguous overload for %qs in %<%s %E%>",
4152 opname, opname, arg1);
4154 error ("no match for %qs in %<%s %E%>",
4155 opname, opname, arg1);
4161 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
4162 opname, arg1, opname, arg2);
4164 error ("no match for %<operator%s%> in %<%E %s %E%>",
4165 opname, arg1, opname, arg2);
4168 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
4169 opname, opname, arg1);
4171 error ("no match for %<operator%s%> in %<%s%E%>",
4172 opname, opname, arg1);
4177 /* Return the implicit conversion sequence that could be used to
4178 convert E1 to E2 in [expr.cond]. */
4181 conditional_conversion (tree e1, tree e2)
4183 tree t1 = non_reference (TREE_TYPE (e1));
4184 tree t2 = non_reference (TREE_TYPE (e2));
4190 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4191 implicitly converted (clause _conv_) to the type "lvalue reference to
4192 T2", subject to the constraint that in the conversion the
4193 reference must bind directly (_dcl.init.ref_) to an lvalue. */
4194 if (real_lvalue_p (e2))
4196 conv = implicit_conversion (build_reference_type (t2),
4200 LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND
4201 |LOOKUP_ONLYCONVERTING);
4208 If E1 and E2 have class type, and the underlying class types are
4209 the same or one is a base class of the other: E1 can be converted
4210 to match E2 if the class of T2 is the same type as, or a base
4211 class of, the class of T1, and the cv-qualification of T2 is the
4212 same cv-qualification as, or a greater cv-qualification than, the
4213 cv-qualification of T1. If the conversion is applied, E1 is
4214 changed to an rvalue of type T2 that still refers to the original
4215 source class object (or the appropriate subobject thereof). */
4216 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
4217 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
4219 if (good_base && at_least_as_qualified_p (t2, t1))
4221 conv = build_identity_conv (t1, e1);
4222 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
4223 TYPE_MAIN_VARIANT (t2)))
4224 conv = build_conv (ck_base, t2, conv);
4226 conv = build_conv (ck_rvalue, t2, conv);
4235 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4236 converted to the type that expression E2 would have if E2 were
4237 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4238 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
4242 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4243 arguments to the conditional expression. */
4246 build_conditional_expr_1 (tree arg1, tree arg2, tree arg3,
4247 tsubst_flags_t complain)
4251 tree result = NULL_TREE;
4252 tree result_type = NULL_TREE;
4253 bool lvalue_p = true;
4254 struct z_candidate *candidates = 0;
4255 struct z_candidate *cand;
4258 /* As a G++ extension, the second argument to the conditional can be
4259 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4260 c'.) If the second operand is omitted, make sure it is
4261 calculated only once. */
4264 if (complain & tf_error)
4265 pedwarn (input_location, OPT_pedantic,
4266 "ISO C++ forbids omitting the middle term of a ?: expression");
4268 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4269 if (real_lvalue_p (arg1))
4270 arg2 = arg1 = stabilize_reference (arg1);
4272 arg2 = arg1 = save_expr (arg1);
4277 The first expression is implicitly converted to bool (clause
4279 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
4282 /* If something has already gone wrong, just pass that fact up the
4284 if (error_operand_p (arg1)
4285 || error_operand_p (arg2)
4286 || error_operand_p (arg3))
4287 return error_mark_node;
4291 If either the second or the third operand has type (possibly
4292 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4293 array-to-pointer (_conv.array_), and function-to-pointer
4294 (_conv.func_) standard conversions are performed on the second
4295 and third operands. */
4296 arg2_type = unlowered_expr_type (arg2);
4297 arg3_type = unlowered_expr_type (arg3);
4298 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
4300 /* Do the conversions. We don't these for `void' type arguments
4301 since it can't have any effect and since decay_conversion
4302 does not handle that case gracefully. */
4303 if (!VOID_TYPE_P (arg2_type))
4304 arg2 = decay_conversion (arg2);
4305 if (!VOID_TYPE_P (arg3_type))
4306 arg3 = decay_conversion (arg3);
4307 arg2_type = TREE_TYPE (arg2);
4308 arg3_type = TREE_TYPE (arg3);
4312 One of the following shall hold:
4314 --The second or the third operand (but not both) is a
4315 throw-expression (_except.throw_); the result is of the
4316 type of the other and is an rvalue.
4318 --Both the second and the third operands have type void; the
4319 result is of type void and is an rvalue.
4321 We must avoid calling force_rvalue for expressions of type
4322 "void" because it will complain that their value is being
4324 if (TREE_CODE (arg2) == THROW_EXPR
4325 && TREE_CODE (arg3) != THROW_EXPR)
4327 if (!VOID_TYPE_P (arg3_type))
4329 arg3 = force_rvalue (arg3, complain);
4330 if (arg3 == error_mark_node)
4331 return error_mark_node;
4333 arg3_type = TREE_TYPE (arg3);
4334 result_type = arg3_type;
4336 else if (TREE_CODE (arg2) != THROW_EXPR
4337 && TREE_CODE (arg3) == THROW_EXPR)
4339 if (!VOID_TYPE_P (arg2_type))
4341 arg2 = force_rvalue (arg2, complain);
4342 if (arg2 == error_mark_node)
4343 return error_mark_node;
4345 arg2_type = TREE_TYPE (arg2);
4346 result_type = arg2_type;
4348 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
4349 result_type = void_type_node;
4352 if (complain & tf_error)
4354 if (VOID_TYPE_P (arg2_type))
4355 error ("second operand to the conditional operator "
4356 "is of type %<void%>, "
4357 "but the third operand is neither a throw-expression "
4358 "nor of type %<void%>");
4360 error ("third operand to the conditional operator "
4361 "is of type %<void%>, "
4362 "but the second operand is neither a throw-expression "
4363 "nor of type %<void%>");
4365 return error_mark_node;
4369 goto valid_operands;
4373 Otherwise, if the second and third operand have different types,
4374 and either has (possibly cv-qualified) class type, an attempt is
4375 made to convert each of those operands to the type of the other. */
4376 else if (!same_type_p (arg2_type, arg3_type)
4377 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4382 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4383 p = conversion_obstack_alloc (0);
4385 conv2 = conditional_conversion (arg2, arg3);
4386 conv3 = conditional_conversion (arg3, arg2);
4390 If both can be converted, or one can be converted but the
4391 conversion is ambiguous, the program is ill-formed. If
4392 neither can be converted, the operands are left unchanged and
4393 further checking is performed as described below. If exactly
4394 one conversion is possible, that conversion is applied to the
4395 chosen operand and the converted operand is used in place of
4396 the original operand for the remainder of this section. */
4397 if ((conv2 && !conv2->bad_p
4398 && conv3 && !conv3->bad_p)
4399 || (conv2 && conv2->kind == ck_ambig)
4400 || (conv3 && conv3->kind == ck_ambig))
4402 error ("operands to ?: have different types %qT and %qT",
4403 arg2_type, arg3_type);
4404 result = error_mark_node;
4406 else if (conv2 && (!conv2->bad_p || !conv3))
4408 arg2 = convert_like (conv2, arg2, complain);
4409 arg2 = convert_from_reference (arg2);
4410 arg2_type = TREE_TYPE (arg2);
4411 /* Even if CONV2 is a valid conversion, the result of the
4412 conversion may be invalid. For example, if ARG3 has type
4413 "volatile X", and X does not have a copy constructor
4414 accepting a "volatile X&", then even if ARG2 can be
4415 converted to X, the conversion will fail. */
4416 if (error_operand_p (arg2))
4417 result = error_mark_node;
4419 else if (conv3 && (!conv3->bad_p || !conv2))
4421 arg3 = convert_like (conv3, arg3, complain);
4422 arg3 = convert_from_reference (arg3);
4423 arg3_type = TREE_TYPE (arg3);
4424 if (error_operand_p (arg3))
4425 result = error_mark_node;
4428 /* Free all the conversions we allocated. */
4429 obstack_free (&conversion_obstack, p);
4434 /* If, after the conversion, both operands have class type,
4435 treat the cv-qualification of both operands as if it were the
4436 union of the cv-qualification of the operands.
4438 The standard is not clear about what to do in this
4439 circumstance. For example, if the first operand has type
4440 "const X" and the second operand has a user-defined
4441 conversion to "volatile X", what is the type of the second
4442 operand after this step? Making it be "const X" (matching
4443 the first operand) seems wrong, as that discards the
4444 qualification without actually performing a copy. Leaving it
4445 as "volatile X" seems wrong as that will result in the
4446 conditional expression failing altogether, even though,
4447 according to this step, the one operand could be converted to
4448 the type of the other. */
4449 if ((conv2 || conv3)
4450 && CLASS_TYPE_P (arg2_type)
4451 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
4452 arg2_type = arg3_type =
4453 cp_build_qualified_type (arg2_type,
4454 cp_type_quals (arg2_type)
4455 | cp_type_quals (arg3_type));
4460 If the second and third operands are lvalues and have the same
4461 type, the result is of that type and is an lvalue. */
4462 if (real_lvalue_p (arg2)
4463 && real_lvalue_p (arg3)
4464 && same_type_p (arg2_type, arg3_type))
4466 result_type = arg2_type;
4467 arg2 = mark_lvalue_use (arg2);
4468 arg3 = mark_lvalue_use (arg3);
4469 goto valid_operands;
4474 Otherwise, the result is an rvalue. If the second and third
4475 operand do not have the same type, and either has (possibly
4476 cv-qualified) class type, overload resolution is used to
4477 determine the conversions (if any) to be applied to the operands
4478 (_over.match.oper_, _over.built_). */
4480 if (!same_type_p (arg2_type, arg3_type)
4481 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4487 /* Rearrange the arguments so that add_builtin_candidate only has
4488 to know about two args. In build_builtin_candidate, the
4489 arguments are unscrambled. */
4493 add_builtin_candidates (&candidates,
4496 ansi_opname (COND_EXPR),
4502 If the overload resolution fails, the program is
4504 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4507 if (complain & tf_error)
4509 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4510 print_z_candidates (location_of (arg1), candidates);
4512 return error_mark_node;
4514 cand = tourney (candidates);
4517 if (complain & tf_error)
4519 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4520 print_z_candidates (location_of (arg1), candidates);
4522 return error_mark_node;
4527 Otherwise, the conversions thus determined are applied, and
4528 the converted operands are used in place of the original
4529 operands for the remainder of this section. */
4530 conv = cand->convs[0];
4531 arg1 = convert_like (conv, arg1, complain);
4532 conv = cand->convs[1];
4533 arg2 = convert_like (conv, arg2, complain);
4534 arg2_type = TREE_TYPE (arg2);
4535 conv = cand->convs[2];
4536 arg3 = convert_like (conv, arg3, complain);
4537 arg3_type = TREE_TYPE (arg3);
4542 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
4543 and function-to-pointer (_conv.func_) standard conversions are
4544 performed on the second and third operands.
4546 We need to force the lvalue-to-rvalue conversion here for class types,
4547 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
4548 that isn't wrapped with a TARGET_EXPR plays havoc with exception
4551 arg2 = force_rvalue (arg2, complain);
4552 if (!CLASS_TYPE_P (arg2_type))
4553 arg2_type = TREE_TYPE (arg2);
4555 arg3 = force_rvalue (arg3, complain);
4556 if (!CLASS_TYPE_P (arg3_type))
4557 arg3_type = TREE_TYPE (arg3);
4559 if (arg2 == error_mark_node || arg3 == error_mark_node)
4560 return error_mark_node;
4564 After those conversions, one of the following shall hold:
4566 --The second and third operands have the same type; the result is of
4568 if (same_type_p (arg2_type, arg3_type))
4569 result_type = arg2_type;
4572 --The second and third operands have arithmetic or enumeration
4573 type; the usual arithmetic conversions are performed to bring
4574 them to a common type, and the result is of that type. */
4575 else if ((ARITHMETIC_TYPE_P (arg2_type)
4576 || UNSCOPED_ENUM_P (arg2_type))
4577 && (ARITHMETIC_TYPE_P (arg3_type)
4578 || UNSCOPED_ENUM_P (arg3_type)))
4580 /* In this case, there is always a common type. */
4581 result_type = type_after_usual_arithmetic_conversions (arg2_type,
4583 do_warn_double_promotion (result_type, arg2_type, arg3_type,
4584 "implicit conversion from %qT to %qT to "
4585 "match other result of conditional",
4588 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
4589 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
4591 if (complain & tf_warning)
4593 "enumeral mismatch in conditional expression: %qT vs %qT",
4594 arg2_type, arg3_type);
4596 else if (extra_warnings
4597 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
4598 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
4599 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
4600 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
4602 if (complain & tf_warning)
4604 "enumeral and non-enumeral type in conditional expression");
4607 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4608 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4612 --The second and third operands have pointer type, or one has
4613 pointer type and the other is a null pointer constant; pointer
4614 conversions (_conv.ptr_) and qualification conversions
4615 (_conv.qual_) are performed to bring them to their composite
4616 pointer type (_expr.rel_). The result is of the composite
4619 --The second and third operands have pointer to member type, or
4620 one has pointer to member type and the other is a null pointer
4621 constant; pointer to member conversions (_conv.mem_) and
4622 qualification conversions (_conv.qual_) are performed to bring
4623 them to a common type, whose cv-qualification shall match the
4624 cv-qualification of either the second or the third operand.
4625 The result is of the common type. */
4626 else if ((null_ptr_cst_p (arg2)
4627 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
4628 || (null_ptr_cst_p (arg3)
4629 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
4630 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
4631 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
4632 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
4634 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
4635 arg3, CPO_CONDITIONAL_EXPR,
4637 if (result_type == error_mark_node)
4638 return error_mark_node;
4639 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4640 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4645 if (complain & tf_error)
4646 error ("operands to ?: have different types %qT and %qT",
4647 arg2_type, arg3_type);
4648 return error_mark_node;
4652 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4653 if (!cp_unevaluated_operand)
4654 /* Avoid folding within decltype (c++/42013) and noexcept. */
4655 result = fold_if_not_in_template (result);
4657 /* We can't use result_type below, as fold might have returned a
4662 /* Expand both sides into the same slot, hopefully the target of
4663 the ?: expression. We used to check for TARGET_EXPRs here,
4664 but now we sometimes wrap them in NOP_EXPRs so the test would
4666 if (CLASS_TYPE_P (TREE_TYPE (result)))
4667 result = get_target_expr (result);
4668 /* If this expression is an rvalue, but might be mistaken for an
4669 lvalue, we must add a NON_LVALUE_EXPR. */
4670 result = rvalue (result);
4676 /* Wrapper for above. */
4679 build_conditional_expr (tree arg1, tree arg2, tree arg3,
4680 tsubst_flags_t complain)
4683 bool subtime = timevar_cond_start (TV_OVERLOAD);
4684 ret = build_conditional_expr_1 (arg1, arg2, arg3, complain);
4685 timevar_cond_stop (TV_OVERLOAD, subtime);
4689 /* OPERAND is an operand to an expression. Perform necessary steps
4690 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4694 prep_operand (tree operand)
4698 if (CLASS_TYPE_P (TREE_TYPE (operand))
4699 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4700 /* Make sure the template type is instantiated now. */
4701 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4707 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4708 OVERLOAD) to the CANDIDATES, returning an updated list of
4709 CANDIDATES. The ARGS are the arguments provided to the call;
4710 if FIRST_ARG is non-null it is the implicit object argument,
4711 otherwise the first element of ARGS is used if needed. The
4712 EXPLICIT_TARGS are explicit template arguments provided.
4713 TEMPLATE_ONLY is true if only template functions should be
4714 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4715 add_function_candidate. */
4718 add_candidates (tree fns, tree first_arg, const VEC(tree,gc) *args,
4720 tree explicit_targs, bool template_only,
4721 tree conversion_path, tree access_path,
4723 struct z_candidate **candidates)
4726 const VEC(tree,gc) *non_static_args;
4727 bool check_list_ctor;
4728 bool check_converting;
4729 unification_kind_t strict;
4735 /* Precalculate special handling of constructors and conversion ops. */
4736 fn = OVL_CURRENT (fns);
4737 if (DECL_CONV_FN_P (fn))
4739 check_list_ctor = false;
4740 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4741 if (flags & LOOKUP_NO_CONVERSION)
4742 /* We're doing return_type(x). */
4743 strict = DEDUCE_CONV;
4745 /* We're doing x.operator return_type(). */
4746 strict = DEDUCE_EXACT;
4747 /* [over.match.funcs] For conversion functions, the function
4748 is considered to be a member of the class of the implicit
4749 object argument for the purpose of defining the type of
4750 the implicit object parameter. */
4751 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (first_arg)));
4755 if (DECL_CONSTRUCTOR_P (fn))
4757 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
4758 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4762 check_list_ctor = false;
4763 check_converting = false;
4765 strict = DEDUCE_CALL;
4766 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4770 non_static_args = args;
4772 /* Delay creating the implicit this parameter until it is needed. */
4773 non_static_args = NULL;
4775 for (; fns; fns = OVL_NEXT (fns))
4778 const VEC(tree,gc) *fn_args;
4780 fn = OVL_CURRENT (fns);
4782 if (check_converting && DECL_NONCONVERTING_P (fn))
4784 if (check_list_ctor && !is_list_ctor (fn))
4787 /* Figure out which set of arguments to use. */
4788 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4790 /* If this function is a non-static member and we didn't get an
4791 implicit object argument, move it out of args. */
4792 if (first_arg == NULL_TREE)
4796 VEC(tree,gc) *tempvec
4797 = VEC_alloc (tree, gc, VEC_length (tree, args) - 1);
4798 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4799 VEC_quick_push (tree, tempvec, arg);
4800 non_static_args = tempvec;
4801 first_arg = build_this (VEC_index (tree, args, 0));
4804 fn_first_arg = first_arg;
4805 fn_args = non_static_args;
4809 /* Otherwise, just use the list of arguments provided. */
4810 fn_first_arg = NULL_TREE;
4814 if (TREE_CODE (fn) == TEMPLATE_DECL)
4815 add_template_candidate (candidates,
4826 else if (!template_only)
4827 add_function_candidate (candidates,
4838 /* Even unsigned enum types promote to signed int. We don't want to
4839 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4840 original argument and ARG is the argument after any conversions
4841 have been applied. We set TREE_NO_WARNING if we have added a cast
4842 from an unsigned enum type to a signed integer type. */
4845 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4847 if (orig_arg != NULL_TREE
4850 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4851 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4852 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4853 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4854 TREE_NO_WARNING (arg) = 1;
4858 build_new_op_1 (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4859 tree *overload, tsubst_flags_t complain)
4861 tree orig_arg1 = arg1;
4862 tree orig_arg2 = arg2;
4863 tree orig_arg3 = arg3;
4864 struct z_candidate *candidates = 0, *cand;
4865 VEC(tree,gc) *arglist;
4868 tree result = NULL_TREE;
4869 bool result_valid_p = false;
4870 enum tree_code code2 = NOP_EXPR;
4871 enum tree_code code_orig_arg1 = ERROR_MARK;
4872 enum tree_code code_orig_arg2 = ERROR_MARK;
4878 if (error_operand_p (arg1)
4879 || error_operand_p (arg2)
4880 || error_operand_p (arg3))
4881 return error_mark_node;
4883 if (code == MODIFY_EXPR)
4885 code2 = TREE_CODE (arg3);
4887 fnname = ansi_assopname (code2);
4890 fnname = ansi_opname (code);
4892 arg1 = prep_operand (arg1);
4898 case VEC_DELETE_EXPR:
4900 /* Use build_op_new_call and build_op_delete_call instead. */
4904 /* Use build_op_call instead. */
4907 case TRUTH_ORIF_EXPR:
4908 case TRUTH_ANDIF_EXPR:
4909 case TRUTH_AND_EXPR:
4911 /* These are saved for the sake of warn_logical_operator. */
4912 code_orig_arg1 = TREE_CODE (arg1);
4913 code_orig_arg2 = TREE_CODE (arg2);
4919 arg2 = prep_operand (arg2);
4920 arg3 = prep_operand (arg3);
4922 if (code == COND_EXPR)
4923 /* Use build_conditional_expr instead. */
4925 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4926 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4929 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4930 arg2 = integer_zero_node;
4932 arglist = VEC_alloc (tree, gc, 3);
4933 VEC_quick_push (tree, arglist, arg1);
4934 if (arg2 != NULL_TREE)
4935 VEC_quick_push (tree, arglist, arg2);
4936 if (arg3 != NULL_TREE)
4937 VEC_quick_push (tree, arglist, arg3);
4939 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4940 p = conversion_obstack_alloc (0);
4942 /* Add namespace-scope operators to the list of functions to
4944 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4945 NULL_TREE, arglist, NULL_TREE,
4946 NULL_TREE, false, NULL_TREE, NULL_TREE,
4947 flags, &candidates);
4948 /* Add class-member operators to the candidate set. */
4949 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4953 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4954 if (fns == error_mark_node)
4956 result = error_mark_node;
4957 goto user_defined_result_ready;
4960 add_candidates (BASELINK_FUNCTIONS (fns),
4961 NULL_TREE, arglist, NULL_TREE,
4963 BASELINK_BINFO (fns),
4964 BASELINK_ACCESS_BINFO (fns),
4965 flags, &candidates);
4970 args[2] = NULL_TREE;
4972 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4978 /* For these, the built-in candidates set is empty
4979 [over.match.oper]/3. We don't want non-strict matches
4980 because exact matches are always possible with built-in
4981 operators. The built-in candidate set for COMPONENT_REF
4982 would be empty too, but since there are no such built-in
4983 operators, we accept non-strict matches for them. */
4988 strict_p = pedantic;
4992 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4997 case POSTINCREMENT_EXPR:
4998 case POSTDECREMENT_EXPR:
4999 /* Don't try anything fancy if we're not allowed to produce
5001 if (!(complain & tf_error))
5002 return error_mark_node;
5004 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5005 distinguish between prefix and postfix ++ and
5006 operator++() was used for both, so we allow this with
5008 if (flags & LOOKUP_COMPLAIN)
5010 const char *msg = (flag_permissive)
5011 ? G_("no %<%D(int)%> declared for postfix %qs,"
5012 " trying prefix operator instead")
5013 : G_("no %<%D(int)%> declared for postfix %qs");
5014 permerror (input_location, msg, fnname,
5015 operator_name_info[code].name);
5018 if (!flag_permissive)
5019 return error_mark_node;
5021 if (code == POSTINCREMENT_EXPR)
5022 code = PREINCREMENT_EXPR;
5024 code = PREDECREMENT_EXPR;
5025 result = build_new_op_1 (code, flags, arg1, NULL_TREE, NULL_TREE,
5026 overload, complain);
5029 /* The caller will deal with these. */
5034 result_valid_p = true;
5038 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5040 /* If one of the arguments of the operator represents
5041 an invalid use of member function pointer, try to report
5042 a meaningful error ... */
5043 if (invalid_nonstatic_memfn_p (arg1, tf_error)
5044 || invalid_nonstatic_memfn_p (arg2, tf_error)
5045 || invalid_nonstatic_memfn_p (arg3, tf_error))
5046 /* We displayed the error message. */;
5049 /* ... Otherwise, report the more generic
5050 "no matching operator found" error */
5051 op_error (code, code2, arg1, arg2, arg3, FALSE);
5052 print_z_candidates (input_location, candidates);
5055 result = error_mark_node;
5061 cand = tourney (candidates);
5064 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5066 op_error (code, code2, arg1, arg2, arg3, TRUE);
5067 print_z_candidates (input_location, candidates);
5069 result = error_mark_node;
5071 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
5074 *overload = cand->fn;
5076 if (resolve_args (arglist, complain) == NULL)
5077 result = error_mark_node;
5079 result = build_over_call (cand, LOOKUP_NORMAL, complain);
5083 /* Give any warnings we noticed during overload resolution. */
5084 if (cand->warnings && (complain & tf_warning))
5086 struct candidate_warning *w;
5087 for (w = cand->warnings; w; w = w->next)
5088 joust (cand, w->loser, 1);
5091 /* Check for comparison of different enum types. */
5100 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
5101 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
5102 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
5103 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
5104 && (complain & tf_warning))
5106 warning (OPT_Wenum_compare,
5107 "comparison between %q#T and %q#T",
5108 TREE_TYPE (arg1), TREE_TYPE (arg2));
5115 /* We need to strip any leading REF_BIND so that bitfields
5116 don't cause errors. This should not remove any important
5117 conversions, because builtins don't apply to class
5118 objects directly. */
5119 conv = cand->convs[0];
5120 if (conv->kind == ck_ref_bind)
5121 conv = conv->u.next;
5122 arg1 = convert_like (conv, arg1, complain);
5126 /* We need to call warn_logical_operator before
5127 converting arg2 to a boolean_type. */
5128 if (complain & tf_warning)
5129 warn_logical_operator (input_location, code, boolean_type_node,
5130 code_orig_arg1, arg1,
5131 code_orig_arg2, arg2);
5133 conv = cand->convs[1];
5134 if (conv->kind == ck_ref_bind)
5135 conv = conv->u.next;
5136 arg2 = convert_like (conv, arg2, complain);
5140 conv = cand->convs[2];
5141 if (conv->kind == ck_ref_bind)
5142 conv = conv->u.next;
5143 arg3 = convert_like (conv, arg3, complain);
5149 user_defined_result_ready:
5151 /* Free all the conversions we allocated. */
5152 obstack_free (&conversion_obstack, p);
5154 if (result || result_valid_p)
5158 avoid_sign_compare_warnings (orig_arg1, arg1);
5159 avoid_sign_compare_warnings (orig_arg2, arg2);
5160 avoid_sign_compare_warnings (orig_arg3, arg3);
5165 return cp_build_modify_expr (arg1, code2, arg2, complain);
5168 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
5170 case TRUTH_ANDIF_EXPR:
5171 case TRUTH_ORIF_EXPR:
5172 case TRUTH_AND_EXPR:
5174 warn_logical_operator (input_location, code, boolean_type_node,
5175 code_orig_arg1, arg1, code_orig_arg2, arg2);
5180 case TRUNC_DIV_EXPR:
5191 case TRUNC_MOD_EXPR:
5195 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
5197 case UNARY_PLUS_EXPR:
5200 case TRUTH_NOT_EXPR:
5201 case PREINCREMENT_EXPR:
5202 case POSTINCREMENT_EXPR:
5203 case PREDECREMENT_EXPR:
5204 case POSTDECREMENT_EXPR:
5207 return cp_build_unary_op (code, arg1, candidates != 0, complain);
5210 return cp_build_array_ref (input_location, arg1, arg2, complain);
5213 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
5217 /* The caller will deal with these. */
5229 /* Wrapper for above. */
5232 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
5233 tree *overload, tsubst_flags_t complain)
5236 bool subtime = timevar_cond_start (TV_OVERLOAD);
5237 ret = build_new_op_1 (code, flags, arg1, arg2, arg3, overload, complain);
5238 timevar_cond_stop (TV_OVERLOAD, subtime);
5242 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5243 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5246 non_placement_deallocation_fn_p (tree t)
5248 /* A template instance is never a usual deallocation function,
5249 regardless of its signature. */
5250 if (TREE_CODE (t) == TEMPLATE_DECL
5251 || primary_template_instantiation_p (t))
5254 /* If a class T has a member deallocation function named operator delete
5255 with exactly one parameter, then that function is a usual
5256 (non-placement) deallocation function. If class T does not declare
5257 such an operator delete but does declare a member deallocation
5258 function named operator delete with exactly two parameters, the second
5259 of which has type std::size_t (18.2), then this function is a usual
5260 deallocation function. */
5261 t = FUNCTION_ARG_CHAIN (t);
5262 if (t == void_list_node
5263 || (t && same_type_p (TREE_VALUE (t), size_type_node)
5264 && TREE_CHAIN (t) == void_list_node))
5269 /* Build a call to operator delete. This has to be handled very specially,
5270 because the restrictions on what signatures match are different from all
5271 other call instances. For a normal delete, only a delete taking (void *)
5272 or (void *, size_t) is accepted. For a placement delete, only an exact
5273 match with the placement new is accepted.
5275 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5276 ADDR is the pointer to be deleted.
5277 SIZE is the size of the memory block to be deleted.
5278 GLOBAL_P is true if the delete-expression should not consider
5279 class-specific delete operators.
5280 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5282 If this call to "operator delete" is being generated as part to
5283 deallocate memory allocated via a new-expression (as per [expr.new]
5284 which requires that if the initialization throws an exception then
5285 we call a deallocation function), then ALLOC_FN is the allocation
5289 build_op_delete_call (enum tree_code code, tree addr, tree size,
5290 bool global_p, tree placement,
5293 tree fn = NULL_TREE;
5294 tree fns, fnname, type, t;
5296 if (addr == error_mark_node)
5297 return error_mark_node;
5299 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
5301 fnname = ansi_opname (code);
5303 if (CLASS_TYPE_P (type)
5304 && COMPLETE_TYPE_P (complete_type (type))
5308 If the result of the lookup is ambiguous or inaccessible, or if
5309 the lookup selects a placement deallocation function, the
5310 program is ill-formed.
5312 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5314 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
5315 if (fns == error_mark_node)
5316 return error_mark_node;
5321 if (fns == NULL_TREE)
5322 fns = lookup_name_nonclass (fnname);
5324 /* Strip const and volatile from addr. */
5325 addr = cp_convert (ptr_type_node, addr);
5329 /* "A declaration of a placement deallocation function matches the
5330 declaration of a placement allocation function if it has the same
5331 number of parameters and, after parameter transformations (8.3.5),
5332 all parameter types except the first are identical."
5334 So we build up the function type we want and ask instantiate_type
5335 to get it for us. */
5336 t = FUNCTION_ARG_CHAIN (alloc_fn);
5337 t = tree_cons (NULL_TREE, ptr_type_node, t);
5338 t = build_function_type (void_type_node, t);
5340 fn = instantiate_type (t, fns, tf_none);
5341 if (fn == error_mark_node)
5344 if (BASELINK_P (fn))
5345 fn = BASELINK_FUNCTIONS (fn);
5347 /* "If the lookup finds the two-parameter form of a usual deallocation
5348 function (3.7.4.2) and that function, considered as a placement
5349 deallocation function, would have been selected as a match for the
5350 allocation function, the program is ill-formed." */
5351 if (non_placement_deallocation_fn_p (fn))
5353 /* But if the class has an operator delete (void *), then that is
5354 the usual deallocation function, so we shouldn't complain
5355 about using the operator delete (void *, size_t). */
5356 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5357 t; t = OVL_NEXT (t))
5359 tree elt = OVL_CURRENT (t);
5360 if (non_placement_deallocation_fn_p (elt)
5361 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
5364 permerror (0, "non-placement deallocation function %q+D", fn);
5365 permerror (input_location, "selected for placement delete");
5370 /* "Any non-placement deallocation function matches a non-placement
5371 allocation function. If the lookup finds a single matching
5372 deallocation function, that function will be called; otherwise, no
5373 deallocation function will be called." */
5374 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5375 t; t = OVL_NEXT (t))
5377 tree elt = OVL_CURRENT (t);
5378 if (non_placement_deallocation_fn_p (elt))
5381 /* "If a class T has a member deallocation function named
5382 operator delete with exactly one parameter, then that
5383 function is a usual (non-placement) deallocation
5384 function. If class T does not declare such an operator
5385 delete but does declare a member deallocation function named
5386 operator delete with exactly two parameters, the second of
5387 which has type std::size_t (18.2), then this function is a
5388 usual deallocation function."
5390 So (void*) beats (void*, size_t). */
5391 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
5396 /* If we have a matching function, call it. */
5399 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5401 /* If the FN is a member function, make sure that it is
5403 if (BASELINK_P (fns))
5404 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
5406 /* Core issue 901: It's ok to new a type with deleted delete. */
5407 if (DECL_DELETED_FN (fn) && alloc_fn)
5412 /* The placement args might not be suitable for overload
5413 resolution at this point, so build the call directly. */
5414 int nargs = call_expr_nargs (placement);
5415 tree *argarray = XALLOCAVEC (tree, nargs);
5418 for (i = 1; i < nargs; i++)
5419 argarray[i] = CALL_EXPR_ARG (placement, i);
5421 return build_cxx_call (fn, nargs, argarray);
5426 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
5427 VEC_quick_push (tree, args, addr);
5428 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
5429 VEC_quick_push (tree, args, size);
5430 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
5431 VEC_free (tree, gc, args);
5438 If no unambiguous matching deallocation function can be found,
5439 propagating the exception does not cause the object's memory to
5444 warning (0, "no corresponding deallocation function for %qD",
5449 error ("no suitable %<operator %s%> for %qT",
5450 operator_name_info[(int)code].name, type);
5451 return error_mark_node;
5454 /* If the current scope isn't allowed to access DECL along
5455 BASETYPE_PATH, give an error. The most derived class in
5456 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
5457 the declaration to use in the error diagnostic. */
5460 enforce_access (tree basetype_path, tree decl, tree diag_decl)
5462 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
5464 if (!accessible_p (basetype_path, decl, true))
5466 if (TREE_PRIVATE (decl))
5467 error ("%q+#D is private", diag_decl);
5468 else if (TREE_PROTECTED (decl))
5469 error ("%q+#D is protected", diag_decl);
5471 error ("%q+#D is inaccessible", diag_decl);
5472 error ("within this context");
5479 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
5480 bitwise or of LOOKUP_* values. If any errors are warnings are
5481 generated, set *DIAGNOSTIC_FN to "error" or "warning",
5482 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
5486 build_temp (tree expr, tree type, int flags,
5487 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
5492 savew = warningcount, savee = errorcount;
5493 args = make_tree_vector_single (expr);
5494 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
5495 &args, type, flags, complain);
5496 release_tree_vector (args);
5497 if (warningcount > savew)
5498 *diagnostic_kind = DK_WARNING;
5499 else if (errorcount > savee)
5500 *diagnostic_kind = DK_ERROR;
5502 *diagnostic_kind = DK_UNSPECIFIED;
5506 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
5507 EXPR is implicitly converted to type TOTYPE.
5508 FN and ARGNUM are used for diagnostics. */
5511 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
5513 tree t = non_reference (totype);
5515 /* Issue warnings about peculiar, but valid, uses of NULL. */
5516 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
5519 warning_at (input_location, OPT_Wconversion_null,
5520 "passing NULL to non-pointer argument %P of %qD",
5523 warning_at (input_location, OPT_Wconversion_null,
5524 "converting to non-pointer type %qT from NULL", t);
5527 /* Issue warnings if "false" is converted to a NULL pointer */
5528 else if (expr == boolean_false_node && POINTER_TYPE_P (t))
5531 warning_at (input_location, OPT_Wconversion_null,
5532 "converting %<false%> to pointer type for argument %P "
5533 "of %qD", argnum, fn);
5535 warning_at (input_location, OPT_Wconversion_null,
5536 "converting %<false%> to pointer type %qT", t);
5540 /* Perform the conversions in CONVS on the expression EXPR. FN and
5541 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
5542 indicates the `this' argument of a method. INNER is nonzero when
5543 being called to continue a conversion chain. It is negative when a
5544 reference binding will be applied, positive otherwise. If
5545 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
5546 conversions will be emitted if appropriate. If C_CAST_P is true,
5547 this conversion is coming from a C-style cast; in that case,
5548 conversions to inaccessible bases are permitted. */
5551 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
5552 int inner, bool issue_conversion_warnings,
5553 bool c_cast_p, tsubst_flags_t complain)
5555 tree totype = convs->type;
5556 diagnostic_t diag_kind;
5559 if (convs->bad_p && !(complain & tf_error))
5560 return error_mark_node;
5563 && convs->kind != ck_user
5564 && convs->kind != ck_list
5565 && convs->kind != ck_ambig
5566 && (convs->kind != ck_ref_bind
5567 || convs->user_conv_p)
5568 && convs->kind != ck_rvalue
5569 && convs->kind != ck_base)
5571 conversion *t = convs;
5573 /* Give a helpful error if this is bad because of excess braces. */
5574 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5575 && SCALAR_TYPE_P (totype)
5576 && CONSTRUCTOR_NELTS (expr) > 0
5577 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
5578 permerror (input_location, "too many braces around initializer for %qT", totype);
5580 for (; t; t = t->u.next)
5582 if (t->kind == ck_user && t->cand->reason)
5584 permerror (input_location, "invalid user-defined conversion "
5585 "from %qT to %qT", TREE_TYPE (expr), totype);
5586 print_z_candidate ("candidate is:", t->cand);
5587 expr = convert_like_real (t, expr, fn, argnum, 1,
5588 /*issue_conversion_warnings=*/false,
5591 if (convs->kind == ck_ref_bind)
5592 return convert_to_reference (totype, expr, CONV_IMPLICIT,
5593 LOOKUP_NORMAL, NULL_TREE);
5595 return cp_convert (totype, expr);
5597 else if (t->kind == ck_user || !t->bad_p)
5599 expr = convert_like_real (t, expr, fn, argnum, 1,
5600 /*issue_conversion_warnings=*/false,
5605 else if (t->kind == ck_ambig)
5606 return convert_like_real (t, expr, fn, argnum, 1,
5607 /*issue_conversion_warnings=*/false,
5610 else if (t->kind == ck_identity)
5614 permerror (input_location, "invalid conversion from %qT to %qT",
5615 TREE_TYPE (expr), totype);
5617 permerror (DECL_SOURCE_LOCATION (fn),
5618 " initializing argument %P of %qD", argnum, fn);
5620 return cp_convert (totype, expr);
5623 if (issue_conversion_warnings && (complain & tf_warning))
5624 conversion_null_warnings (totype, expr, fn, argnum);
5626 switch (convs->kind)
5630 struct z_candidate *cand = convs->cand;
5631 tree convfn = cand->fn;
5634 /* If we're initializing from {}, it's value-initialization. */
5635 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5636 && CONSTRUCTOR_NELTS (expr) == 0
5637 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
5639 expr = build_value_init (totype, complain);
5640 expr = get_target_expr_sfinae (expr, complain);
5641 if (expr != error_mark_node)
5642 TARGET_EXPR_LIST_INIT_P (expr) = true;
5646 expr = mark_rvalue_use (expr);
5648 /* When converting from an init list we consider explicit
5649 constructors, but actually trying to call one is an error. */
5650 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
5651 /* Unless we're calling it for value-initialization from an
5652 empty list, since that is handled separately in 8.5.4. */
5653 && cand->num_convs > 0)
5655 error ("converting to %qT from initializer list would use "
5656 "explicit constructor %qD", totype, convfn);
5659 /* Set user_conv_p on the argument conversions, so rvalue/base
5660 handling knows not to allow any more UDCs. */
5661 for (i = 0; i < cand->num_convs; ++i)
5662 cand->convs[i]->user_conv_p = true;
5664 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
5666 /* If this is a constructor or a function returning an aggr type,
5667 we need to build up a TARGET_EXPR. */
5668 if (DECL_CONSTRUCTOR_P (convfn))
5670 expr = build_cplus_new (totype, expr, complain);
5672 /* Remember that this was list-initialization. */
5673 if (convs->check_narrowing && expr != error_mark_node)
5674 TARGET_EXPR_LIST_INIT_P (expr) = true;
5680 expr = mark_rvalue_use (expr);
5681 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
5683 int nelts = CONSTRUCTOR_NELTS (expr);
5685 expr = build_value_init (totype, complain);
5686 else if (nelts == 1)
5687 expr = CONSTRUCTOR_ELT (expr, 0)->value;
5692 if (type_unknown_p (expr))
5693 expr = instantiate_type (totype, expr, complain);
5694 /* Convert a constant to its underlying value, unless we are
5695 about to bind it to a reference, in which case we need to
5696 leave it as an lvalue. */
5699 expr = decl_constant_value (expr);
5700 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
5701 /* If __null has been converted to an integer type, we do not
5702 want to warn about uses of EXPR as an integer, rather than
5704 expr = build_int_cst (totype, 0);
5708 /* We leave bad_p off ck_ambig because overload resolution considers
5709 it valid, it just fails when we try to perform it. So we need to
5710 check complain here, too. */
5711 if (complain & tf_error)
5713 /* Call build_user_type_conversion again for the error. */
5714 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL);
5716 error (" initializing argument %P of %q+D", argnum, fn);
5718 return error_mark_node;
5722 /* Conversion to std::initializer_list<T>. */
5723 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
5724 tree new_ctor = build_constructor (init_list_type_node, NULL);
5725 unsigned len = CONSTRUCTOR_NELTS (expr);
5726 tree array, val, field;
5727 VEC(constructor_elt,gc) *vec = NULL;
5730 /* Convert all the elements. */
5731 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
5733 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
5734 1, false, false, complain);
5735 if (sub == error_mark_node)
5737 if (!BRACE_ENCLOSED_INITIALIZER_P (val))
5738 check_narrowing (TREE_TYPE (sub), val);
5739 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
5740 if (!TREE_CONSTANT (sub))
5741 TREE_CONSTANT (new_ctor) = false;
5743 /* Build up the array. */
5744 elttype = cp_build_qualified_type
5745 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
5746 array = build_array_of_n_type (elttype, len);
5747 array = finish_compound_literal (array, new_ctor, complain);
5749 /* Build up the initializer_list object. */
5750 totype = complete_type (totype);
5751 field = next_initializable_field (TYPE_FIELDS (totype));
5752 CONSTRUCTOR_APPEND_ELT (vec, field, decay_conversion (array));
5753 field = next_initializable_field (DECL_CHAIN (field));
5754 CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len));
5755 new_ctor = build_constructor (totype, vec);
5756 return get_target_expr (new_ctor);
5760 if (TREE_CODE (totype) == COMPLEX_TYPE)
5762 tree real = CONSTRUCTOR_ELT (expr, 0)->value;
5763 tree imag = CONSTRUCTOR_ELT (expr, 1)->value;
5764 real = perform_implicit_conversion (TREE_TYPE (totype),
5766 imag = perform_implicit_conversion (TREE_TYPE (totype),
5768 expr = build2 (COMPLEX_EXPR, totype, real, imag);
5769 return fold_if_not_in_template (expr);
5771 return get_target_expr (digest_init (totype, expr, complain));
5777 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5778 convs->kind == ck_ref_bind ? -1 : 1,
5779 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5782 if (expr == error_mark_node)
5783 return error_mark_node;
5785 switch (convs->kind)
5788 expr = decay_conversion (expr);
5789 if (! MAYBE_CLASS_TYPE_P (totype))
5791 /* Else fall through. */
5793 if (convs->kind == ck_base && !convs->need_temporary_p)
5795 /* We are going to bind a reference directly to a base-class
5796 subobject of EXPR. */
5797 /* Build an expression for `*((base*) &expr)'. */
5798 expr = cp_build_addr_expr (expr, complain);
5799 expr = convert_to_base (expr, build_pointer_type (totype),
5800 !c_cast_p, /*nonnull=*/true, complain);
5801 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5805 /* Copy-initialization where the cv-unqualified version of the source
5806 type is the same class as, or a derived class of, the class of the
5807 destination [is treated as direct-initialization]. [dcl.init] */
5808 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5809 if (convs->user_conv_p)
5810 /* This conversion is being done in the context of a user-defined
5811 conversion (i.e. the second step of copy-initialization), so
5812 don't allow any more. */
5813 flags |= LOOKUP_NO_CONVERSION;
5814 if (convs->rvaluedness_matches_p)
5815 flags |= LOOKUP_PREFER_RVALUE;
5816 if (TREE_CODE (expr) == TARGET_EXPR
5817 && TARGET_EXPR_LIST_INIT_P (expr))
5818 /* Copy-list-initialization doesn't actually involve a copy. */
5820 expr = build_temp (expr, totype, flags, &diag_kind, complain);
5821 if (diag_kind && fn && complain)
5822 emit_diagnostic (diag_kind, DECL_SOURCE_LOCATION (fn), 0,
5823 " initializing argument %P of %qD", argnum, fn);
5824 return build_cplus_new (totype, expr, complain);
5828 tree ref_type = totype;
5830 if (convs->bad_p && !convs->u.next->bad_p)
5832 gcc_assert (TYPE_REF_IS_RVALUE (ref_type)
5833 && real_lvalue_p (expr));
5835 error ("cannot bind %qT lvalue to %qT",
5836 TREE_TYPE (expr), totype);
5838 error (" initializing argument %P of %q+D", argnum, fn);
5839 return error_mark_node;
5842 /* If necessary, create a temporary.
5844 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5845 that need temporaries, even when their types are reference
5846 compatible with the type of reference being bound, so the
5847 upcoming call to cp_build_addr_expr doesn't fail. */
5848 if (convs->need_temporary_p
5849 || TREE_CODE (expr) == CONSTRUCTOR
5850 || TREE_CODE (expr) == VA_ARG_EXPR)
5852 /* Otherwise, a temporary of type "cv1 T1" is created and
5853 initialized from the initializer expression using the rules
5854 for a non-reference copy-initialization (8.5). */
5856 tree type = TREE_TYPE (ref_type);
5857 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5859 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5860 (type, convs->u.next->type));
5861 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
5862 && !TYPE_REF_IS_RVALUE (ref_type))
5864 /* If the reference is volatile or non-const, we
5865 cannot create a temporary. */
5866 if (lvalue & clk_bitfield)
5867 error ("cannot bind bitfield %qE to %qT",
5869 else if (lvalue & clk_packed)
5870 error ("cannot bind packed field %qE to %qT",
5873 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5874 return error_mark_node;
5876 /* If the source is a packed field, and we must use a copy
5877 constructor, then building the target expr will require
5878 binding the field to the reference parameter to the
5879 copy constructor, and we'll end up with an infinite
5880 loop. If we can use a bitwise copy, then we'll be
5882 if ((lvalue & clk_packed)
5883 && CLASS_TYPE_P (type)
5884 && type_has_nontrivial_copy_init (type))
5886 error ("cannot bind packed field %qE to %qT",
5888 return error_mark_node;
5890 if (lvalue & clk_bitfield)
5892 expr = convert_bitfield_to_declared_type (expr);
5893 expr = fold_convert (type, expr);
5895 expr = build_target_expr_with_type (expr, type, complain);
5898 /* Take the address of the thing to which we will bind the
5900 expr = cp_build_addr_expr (expr, complain);
5901 if (expr == error_mark_node)
5902 return error_mark_node;
5904 /* Convert it to a pointer to the type referred to by the
5905 reference. This will adjust the pointer if a derived to
5906 base conversion is being performed. */
5907 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5909 /* Convert the pointer to the desired reference type. */
5910 return build_nop (ref_type, expr);
5914 return decay_conversion (expr);
5917 /* Warn about deprecated conversion if appropriate. */
5918 string_conv_p (totype, expr, 1);
5923 expr = convert_to_base (expr, totype, !c_cast_p,
5924 /*nonnull=*/false, complain);
5925 return build_nop (totype, expr);
5928 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5929 c_cast_p, complain);
5935 if (convs->check_narrowing)
5936 check_narrowing (totype, expr);
5938 if (issue_conversion_warnings && (complain & tf_warning))
5939 expr = convert_and_check (totype, expr);
5941 expr = convert (totype, expr);
5946 /* ARG is being passed to a varargs function. Perform any conversions
5947 required. Return the converted value. */
5950 convert_arg_to_ellipsis (tree arg)
5956 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5957 standard conversions are performed. */
5958 arg = decay_conversion (arg);
5959 arg_type = TREE_TYPE (arg);
5962 If the argument has integral or enumeration type that is subject
5963 to the integral promotions (_conv.prom_), or a floating point
5964 type that is subject to the floating point promotion
5965 (_conv.fpprom_), the value of the argument is converted to the
5966 promoted type before the call. */
5967 if (TREE_CODE (arg_type) == REAL_TYPE
5968 && (TYPE_PRECISION (arg_type)
5969 < TYPE_PRECISION (double_type_node))
5970 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
5972 if (warn_double_promotion && !c_inhibit_evaluation_warnings)
5973 warning (OPT_Wdouble_promotion,
5974 "implicit conversion from %qT to %qT when passing "
5975 "argument to function",
5976 arg_type, double_type_node);
5977 arg = convert_to_real (double_type_node, arg);
5979 else if (NULLPTR_TYPE_P (arg_type))
5980 arg = null_pointer_node;
5981 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
5983 if (SCOPED_ENUM_P (arg_type) && !abi_version_at_least (6))
5985 warning (OPT_Wabi, "scoped enum %qT will not promote to an "
5986 "integral type in a future version of GCC", arg_type);
5987 arg = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg);
5989 arg = perform_integral_promotions (arg);
5992 arg = require_complete_type (arg);
5993 arg_type = TREE_TYPE (arg);
5995 if (arg != error_mark_node
5996 /* In a template (or ill-formed code), we can have an incomplete type
5997 even after require_complete_type, in which case we don't know
5998 whether it has trivial copy or not. */
5999 && COMPLETE_TYPE_P (arg_type))
6001 /* Build up a real lvalue-to-rvalue conversion in case the
6002 copy constructor is trivial but not callable. */
6003 if (!cp_unevaluated_operand && CLASS_TYPE_P (arg_type))
6004 force_rvalue (arg, tf_warning_or_error);
6006 /* [expr.call] 5.2.2/7:
6007 Passing a potentially-evaluated argument of class type (Clause 9)
6008 with a non-trivial copy constructor or a non-trivial destructor
6009 with no corresponding parameter is conditionally-supported, with
6010 implementation-defined semantics.
6012 We used to just warn here and do a bitwise copy, but now
6013 cp_expr_size will abort if we try to do that.
6015 If the call appears in the context of a sizeof expression,
6016 it is not potentially-evaluated. */
6017 if (cp_unevaluated_operand == 0
6018 && (type_has_nontrivial_copy_init (arg_type)
6019 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
6020 error ("cannot pass objects of non-trivially-copyable "
6021 "type %q#T through %<...%>", arg_type);
6027 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6030 build_x_va_arg (tree expr, tree type)
6032 if (processing_template_decl)
6033 return build_min (VA_ARG_EXPR, type, expr);
6035 type = complete_type_or_else (type, NULL_TREE);
6037 if (expr == error_mark_node || !type)
6038 return error_mark_node;
6040 expr = mark_lvalue_use (expr);
6042 if (type_has_nontrivial_copy_init (type)
6043 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
6044 || TREE_CODE (type) == REFERENCE_TYPE)
6046 /* Remove reference types so we don't ICE later on. */
6047 tree type1 = non_reference (type);
6048 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
6049 error ("cannot receive objects of non-trivially-copyable type %q#T "
6050 "through %<...%>; ", type);
6051 expr = convert (build_pointer_type (type1), null_node);
6052 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
6056 return build_va_arg (input_location, expr, type);
6059 /* TYPE has been given to va_arg. Apply the default conversions which
6060 would have happened when passed via ellipsis. Return the promoted
6061 type, or the passed type if there is no change. */
6064 cxx_type_promotes_to (tree type)
6068 /* Perform the array-to-pointer and function-to-pointer
6070 type = type_decays_to (type);
6072 promote = type_promotes_to (type);
6073 if (same_type_p (type, promote))
6079 /* ARG is a default argument expression being passed to a parameter of
6080 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6081 zero-based argument number. Do any required conversions. Return
6082 the converted value. */
6084 static GTY(()) VEC(tree,gc) *default_arg_context;
6086 push_defarg_context (tree fn)
6087 { VEC_safe_push (tree, gc, default_arg_context, fn); }
6089 pop_defarg_context (void)
6090 { VEC_pop (tree, default_arg_context); }
6093 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
6098 /* See through clones. */
6099 fn = DECL_ORIGIN (fn);
6101 /* Detect recursion. */
6102 FOR_EACH_VEC_ELT (tree, default_arg_context, i, t)
6105 error ("recursive evaluation of default argument for %q#D", fn);
6106 return error_mark_node;
6109 /* If the ARG is an unparsed default argument expression, the
6110 conversion cannot be performed. */
6111 if (TREE_CODE (arg) == DEFAULT_ARG)
6113 error ("call to %qD uses the default argument for parameter %P, which "
6114 "is not yet defined", fn, parmnum);
6115 return error_mark_node;
6118 push_defarg_context (fn);
6120 if (fn && DECL_TEMPLATE_INFO (fn))
6121 arg = tsubst_default_argument (fn, type, arg);
6127 The names in the expression are bound, and the semantic
6128 constraints are checked, at the point where the default
6129 expressions appears.
6131 we must not perform access checks here. */
6132 push_deferring_access_checks (dk_no_check);
6133 /* We must make a copy of ARG, in case subsequent processing
6134 alters any part of it. */
6135 arg = break_out_target_exprs (arg);
6136 if (TREE_CODE (arg) == CONSTRUCTOR)
6138 arg = digest_init (type, arg, tf_warning_or_error);
6139 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6140 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6141 tf_warning_or_error);
6145 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6146 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6147 tf_warning_or_error);
6148 arg = convert_for_arg_passing (type, arg);
6150 pop_deferring_access_checks();
6152 pop_defarg_context ();
6157 /* Returns the type which will really be used for passing an argument of
6161 type_passed_as (tree type)
6163 /* Pass classes with copy ctors by invisible reference. */
6164 if (TREE_ADDRESSABLE (type))
6166 type = build_reference_type (type);
6167 /* There are no other pointers to this temporary. */
6168 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
6170 else if (targetm.calls.promote_prototypes (type)
6171 && INTEGRAL_TYPE_P (type)
6172 && COMPLETE_TYPE_P (type)
6173 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6174 TYPE_SIZE (integer_type_node)))
6175 type = integer_type_node;
6180 /* Actually perform the appropriate conversion. */
6183 convert_for_arg_passing (tree type, tree val)
6187 /* If VAL is a bitfield, then -- since it has already been converted
6188 to TYPE -- it cannot have a precision greater than TYPE.
6190 If it has a smaller precision, we must widen it here. For
6191 example, passing "int f:3;" to a function expecting an "int" will
6192 not result in any conversion before this point.
6194 If the precision is the same we must not risk widening. For
6195 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6196 often have type "int", even though the C++ type for the field is
6197 "long long". If the value is being passed to a function
6198 expecting an "int", then no conversions will be required. But,
6199 if we call convert_bitfield_to_declared_type, the bitfield will
6200 be converted to "long long". */
6201 bitfield_type = is_bitfield_expr_with_lowered_type (val);
6203 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
6204 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
6206 if (val == error_mark_node)
6208 /* Pass classes with copy ctors by invisible reference. */
6209 else if (TREE_ADDRESSABLE (type))
6210 val = build1 (ADDR_EXPR, build_reference_type (type), val);
6211 else if (targetm.calls.promote_prototypes (type)
6212 && INTEGRAL_TYPE_P (type)
6213 && COMPLETE_TYPE_P (type)
6214 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6215 TYPE_SIZE (integer_type_node)))
6216 val = perform_integral_promotions (val);
6217 if (warn_missing_format_attribute)
6219 tree rhstype = TREE_TYPE (val);
6220 const enum tree_code coder = TREE_CODE (rhstype);
6221 const enum tree_code codel = TREE_CODE (type);
6222 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6224 && check_missing_format_attribute (type, rhstype))
6225 warning (OPT_Wmissing_format_attribute,
6226 "argument of function call might be a candidate for a format attribute");
6231 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6232 which no conversions at all should be done. This is true for some
6233 builtins which don't act like normal functions. */
6236 magic_varargs_p (tree fn)
6238 if (DECL_BUILT_IN (fn))
6239 switch (DECL_FUNCTION_CODE (fn))
6241 case BUILT_IN_CLASSIFY_TYPE:
6242 case BUILT_IN_CONSTANT_P:
6243 case BUILT_IN_NEXT_ARG:
6244 case BUILT_IN_VA_START:
6248 return lookup_attribute ("type generic",
6249 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
6255 /* Subroutine of the various build_*_call functions. Overload resolution
6256 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
6257 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
6258 bitmask of various LOOKUP_* flags which apply to the call itself. */
6261 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
6264 const VEC(tree,gc) *args = cand->args;
6265 tree first_arg = cand->first_arg;
6266 conversion **convs = cand->convs;
6268 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
6273 unsigned int arg_index = 0;
6277 bool already_used = false;
6279 /* In a template, there is no need to perform all of the work that
6280 is normally done. We are only interested in the type of the call
6281 expression, i.e., the return type of the function. Any semantic
6282 errors will be deferred until the template is instantiated. */
6283 if (processing_template_decl)
6287 const tree *argarray;
6290 return_type = TREE_TYPE (TREE_TYPE (fn));
6291 nargs = VEC_length (tree, args);
6292 if (first_arg == NULL_TREE)
6293 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
6301 alcarray = XALLOCAVEC (tree, nargs);
6302 alcarray[0] = first_arg;
6303 FOR_EACH_VEC_ELT (tree, args, ix, arg)
6304 alcarray[ix + 1] = arg;
6305 argarray = alcarray;
6307 expr = build_call_array_loc (input_location,
6308 return_type, build_addr_func (fn), nargs,
6310 if (TREE_THIS_VOLATILE (fn) && cfun)
6311 current_function_returns_abnormally = 1;
6312 return convert_from_reference (expr);
6315 /* Give any warnings we noticed during overload resolution. */
6316 if (cand->warnings && (complain & tf_warning))
6318 struct candidate_warning *w;
6319 for (w = cand->warnings; w; w = w->next)
6320 joust (cand, w->loser, 1);
6323 /* Make =delete work with SFINAE. */
6324 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
6325 return error_mark_node;
6327 if (DECL_FUNCTION_MEMBER_P (fn))
6330 /* If FN is a template function, two cases must be considered.
6335 template <class T> void f();
6337 template <class T> struct B {
6341 struct C : A, B<int> {
6343 using B<int>::g; // #2
6346 In case #1 where `A::f' is a member template, DECL_ACCESS is
6347 recorded in the primary template but not in its specialization.
6348 We check access of FN using its primary template.
6350 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
6351 because it is a member of class template B, DECL_ACCESS is
6352 recorded in the specialization `B<int>::g'. We cannot use its
6353 primary template because `B<T>::g' and `B<int>::g' may have
6354 different access. */
6355 if (DECL_TEMPLATE_INFO (fn)
6356 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
6357 access_fn = DECL_TI_TEMPLATE (fn);
6360 if (flags & LOOKUP_SPECULATIVE)
6362 if (!speculative_access_check (cand->access_path, access_fn, fn,
6363 !!(flags & LOOKUP_COMPLAIN)))
6364 return error_mark_node;
6367 perform_or_defer_access_check (cand->access_path, access_fn, fn);
6370 /* If we're checking for implicit delete, don't bother with argument
6372 if (flags & LOOKUP_SPECULATIVE)
6374 if (DECL_DELETED_FN (fn))
6376 if (flags & LOOKUP_COMPLAIN)
6378 return error_mark_node;
6380 if (cand->viable == 1)
6382 else if (!(flags & LOOKUP_COMPLAIN))
6383 /* Reject bad conversions now. */
6384 return error_mark_node;
6385 /* else continue to get conversion error. */
6388 /* Find maximum size of vector to hold converted arguments. */
6389 parmlen = list_length (parm);
6390 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
6391 if (parmlen > nargs)
6393 argarray = XALLOCAVEC (tree, nargs);
6395 /* The implicit parameters to a constructor are not considered by overload
6396 resolution, and must be of the proper type. */
6397 if (DECL_CONSTRUCTOR_P (fn))
6399 if (first_arg != NULL_TREE)
6401 argarray[j++] = first_arg;
6402 first_arg = NULL_TREE;
6406 argarray[j++] = VEC_index (tree, args, arg_index);
6409 parm = TREE_CHAIN (parm);
6410 /* We should never try to call the abstract constructor. */
6411 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
6413 if (DECL_HAS_VTT_PARM_P (fn))
6415 argarray[j++] = VEC_index (tree, args, arg_index);
6417 parm = TREE_CHAIN (parm);
6420 /* Bypass access control for 'this' parameter. */
6421 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6423 tree parmtype = TREE_VALUE (parm);
6424 tree arg = (first_arg != NULL_TREE
6426 : VEC_index (tree, args, arg_index));
6427 tree argtype = TREE_TYPE (arg);
6431 if (convs[i]->bad_p)
6433 if (complain & tf_error)
6434 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
6435 TREE_TYPE (argtype), fn);
6437 return error_mark_node;
6440 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
6441 X is called for an object that is not of type X, or of a type
6442 derived from X, the behavior is undefined.
6444 So we can assume that anything passed as 'this' is non-null, and
6445 optimize accordingly. */
6446 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
6447 /* Convert to the base in which the function was declared. */
6448 gcc_assert (cand->conversion_path != NULL_TREE);
6449 converted_arg = build_base_path (PLUS_EXPR,
6451 cand->conversion_path,
6453 /* Check that the base class is accessible. */
6454 if (!accessible_base_p (TREE_TYPE (argtype),
6455 BINFO_TYPE (cand->conversion_path), true))
6456 error ("%qT is not an accessible base of %qT",
6457 BINFO_TYPE (cand->conversion_path),
6458 TREE_TYPE (argtype));
6459 /* If fn was found by a using declaration, the conversion path
6460 will be to the derived class, not the base declaring fn. We
6461 must convert from derived to base. */
6462 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
6463 TREE_TYPE (parmtype), ba_unique, NULL);
6464 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
6465 base_binfo, 1, complain);
6467 argarray[j++] = converted_arg;
6468 parm = TREE_CHAIN (parm);
6469 if (first_arg != NULL_TREE)
6470 first_arg = NULL_TREE;
6477 gcc_assert (first_arg == NULL_TREE);
6478 for (; arg_index < VEC_length (tree, args) && parm;
6479 parm = TREE_CHAIN (parm), ++arg_index, ++i)
6481 tree type = TREE_VALUE (parm);
6482 tree arg = VEC_index (tree, args, arg_index);
6483 bool conversion_warning = true;
6487 /* If the argument is NULL and used to (implicitly) instantiate a
6488 template function (and bind one of the template arguments to
6489 the type of 'long int'), we don't want to warn about passing NULL
6490 to non-pointer argument.
6491 For example, if we have this template function:
6493 template<typename T> void func(T x) {}
6495 we want to warn (when -Wconversion is enabled) in this case:
6501 but not in this case:
6507 if (arg == null_node
6508 && DECL_TEMPLATE_INFO (fn)
6509 && cand->template_decl
6510 && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS))
6511 conversion_warning = false;
6513 /* Warn about initializer_list deduction that isn't currently in the
6515 if (cxx_dialect > cxx98
6516 && flag_deduce_init_list
6517 && cand->template_decl
6518 && is_std_init_list (non_reference (type))
6519 && BRACE_ENCLOSED_INITIALIZER_P (arg))
6521 tree tmpl = TI_TEMPLATE (cand->template_decl);
6522 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
6523 tree patparm = get_pattern_parm (realparm, tmpl);
6524 tree pattype = TREE_TYPE (patparm);
6525 if (PACK_EXPANSION_P (pattype))
6526 pattype = PACK_EXPANSION_PATTERN (pattype);
6527 pattype = non_reference (pattype);
6529 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
6530 && (cand->explicit_targs == NULL_TREE
6531 || (TREE_VEC_LENGTH (cand->explicit_targs)
6532 <= TEMPLATE_TYPE_IDX (pattype))))
6534 pedwarn (input_location, 0, "deducing %qT as %qT",
6535 non_reference (TREE_TYPE (patparm)),
6536 non_reference (type));
6537 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
6538 pedwarn (input_location, 0,
6539 " (you can disable this with -fno-deduce-init-list)");
6543 val = convert_like_with_context (conv, arg, fn, i-is_method,
6546 : complain & (~tf_warning));
6548 val = convert_for_arg_passing (type, val);
6549 if (val == error_mark_node)
6550 return error_mark_node;
6552 argarray[j++] = val;
6555 /* Default arguments */
6556 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
6557 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
6558 TREE_PURPOSE (parm),
6561 for (; arg_index < VEC_length (tree, args); ++arg_index)
6563 tree a = VEC_index (tree, args, arg_index);
6564 if (magic_varargs_p (fn))
6565 /* Do no conversions for magic varargs. */
6566 a = mark_type_use (a);
6568 a = convert_arg_to_ellipsis (a);
6572 gcc_assert (j <= nargs);
6575 check_function_arguments (TREE_TYPE (fn), nargs, argarray);
6577 /* Avoid actually calling copy constructors and copy assignment operators,
6580 if (! flag_elide_constructors)
6581 /* Do things the hard way. */;
6582 else if (cand->num_convs == 1
6583 && (DECL_COPY_CONSTRUCTOR_P (fn)
6584 || DECL_MOVE_CONSTRUCTOR_P (fn)))
6587 tree arg = argarray[num_artificial_parms_for (fn)];
6589 bool trivial = trivial_fn_p (fn);
6591 /* Pull out the real argument, disregarding const-correctness. */
6593 while (CONVERT_EXPR_P (targ)
6594 || TREE_CODE (targ) == NON_LVALUE_EXPR)
6595 targ = TREE_OPERAND (targ, 0);
6596 if (TREE_CODE (targ) == ADDR_EXPR)
6598 targ = TREE_OPERAND (targ, 0);
6599 if (!same_type_ignoring_top_level_qualifiers_p
6600 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
6609 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6611 /* [class.copy]: the copy constructor is implicitly defined even if
6612 the implementation elided its use. */
6613 if (!trivial || DECL_DELETED_FN (fn))
6616 already_used = true;
6619 /* If we're creating a temp and we already have one, don't create a
6620 new one. If we're not creating a temp but we get one, use
6621 INIT_EXPR to collapse the temp into our target. Otherwise, if the
6622 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
6623 temp or an INIT_EXPR otherwise. */
6625 if (integer_zerop (fa))
6627 if (TREE_CODE (arg) == TARGET_EXPR)
6630 return force_target_expr (DECL_CONTEXT (fn), arg, complain);
6632 else if (TREE_CODE (arg) == TARGET_EXPR || trivial)
6634 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
6637 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
6641 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
6642 && trivial_fn_p (fn)
6643 && !DECL_DELETED_FN (fn))
6645 tree to = stabilize_reference
6646 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
6647 tree type = TREE_TYPE (to);
6648 tree as_base = CLASSTYPE_AS_BASE (type);
6649 tree arg = argarray[1];
6651 if (is_really_empty_class (type))
6653 /* Avoid copying empty classes. */
6654 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
6655 TREE_NO_WARNING (val) = 1;
6656 val = build2 (COMPOUND_EXPR, type, val, to);
6657 TREE_NO_WARNING (val) = 1;
6659 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
6661 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6662 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
6666 /* We must only copy the non-tail padding parts. */
6668 tree array_type, alias_set;
6670 arg2 = TYPE_SIZE_UNIT (as_base);
6671 arg0 = cp_build_addr_expr (to, complain);
6673 array_type = build_array_type (char_type_node,
6675 (size_binop (MINUS_EXPR,
6676 arg2, size_int (1))));
6677 alias_set = build_int_cst (build_pointer_type (type), 0);
6678 t = build2 (MODIFY_EXPR, void_type_node,
6679 build2 (MEM_REF, array_type, arg0, alias_set),
6680 build2 (MEM_REF, array_type, arg, alias_set));
6681 val = build2 (COMPOUND_EXPR, TREE_TYPE (to), t, to);
6682 TREE_NO_WARNING (val) = 1;
6687 else if (DECL_DESTRUCTOR_P (fn)
6688 && trivial_fn_p (fn)
6689 && !DECL_DELETED_FN (fn))
6690 return fold_convert (void_type_node, argarray[0]);
6691 /* FIXME handle trivial default constructor, too. */
6696 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
6699 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
6702 gcc_assert (binfo && binfo != error_mark_node);
6704 /* Warn about deprecated virtual functions now, since we're about
6705 to throw away the decl. */
6706 if (TREE_DEPRECATED (fn))
6707 warn_deprecated_use (fn, NULL_TREE);
6709 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1,
6711 if (TREE_SIDE_EFFECTS (argarray[0]))
6712 argarray[0] = save_expr (argarray[0]);
6713 t = build_pointer_type (TREE_TYPE (fn));
6714 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
6715 fn = build_java_interface_fn_ref (fn, argarray[0]);
6717 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
6721 fn = build_addr_func (fn);
6723 return build_cxx_call (fn, nargs, argarray);
6726 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
6727 This function performs no overload resolution, conversion, or other
6728 high-level operations. */
6731 build_cxx_call (tree fn, int nargs, tree *argarray)
6735 /* Remember roughly where this call is. */
6736 location_t loc = EXPR_LOC_OR_HERE (fn);
6737 fn = build_call_a (fn, nargs, argarray);
6738 SET_EXPR_LOCATION (fn, loc);
6740 fndecl = get_callee_fndecl (fn);
6742 /* Check that arguments to builtin functions match the expectations. */
6744 && DECL_BUILT_IN (fndecl)
6745 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6746 && !check_builtin_function_arguments (fndecl, nargs, argarray))
6747 return error_mark_node;
6749 /* Some built-in function calls will be evaluated at compile-time in
6751 fn = fold_if_not_in_template (fn);
6753 if (VOID_TYPE_P (TREE_TYPE (fn)))
6756 fn = require_complete_type (fn);
6757 if (fn == error_mark_node)
6758 return error_mark_node;
6760 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
6761 fn = build_cplus_new (TREE_TYPE (fn), fn, tf_warning_or_error);
6762 return convert_from_reference (fn);
6765 static GTY(()) tree java_iface_lookup_fn;
6767 /* Make an expression which yields the address of the Java interface
6768 method FN. This is achieved by generating a call to libjava's
6769 _Jv_LookupInterfaceMethodIdx(). */
6772 build_java_interface_fn_ref (tree fn, tree instance)
6774 tree lookup_fn, method, idx;
6775 tree klass_ref, iface, iface_ref;
6778 if (!java_iface_lookup_fn)
6780 tree ftype = build_function_type_list (ptr_type_node,
6781 ptr_type_node, ptr_type_node,
6782 java_int_type_node, NULL_TREE);
6783 java_iface_lookup_fn
6784 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
6785 0, NOT_BUILT_IN, NULL, NULL_TREE);
6788 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
6789 This is the first entry in the vtable. */
6790 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
6791 tf_warning_or_error),
6794 /* Get the java.lang.Class pointer for the interface being called. */
6795 iface = DECL_CONTEXT (fn);
6796 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
6797 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
6798 || DECL_CONTEXT (iface_ref) != iface)
6800 error ("could not find class$ field in java interface type %qT",
6802 return error_mark_node;
6804 iface_ref = build_address (iface_ref);
6805 iface_ref = convert (build_pointer_type (iface), iface_ref);
6807 /* Determine the itable index of FN. */
6809 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
6811 if (!DECL_VIRTUAL_P (method))
6817 idx = build_int_cst (NULL_TREE, i);
6819 lookup_fn = build1 (ADDR_EXPR,
6820 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
6821 java_iface_lookup_fn);
6822 return build_call_nary (ptr_type_node, lookup_fn,
6823 3, klass_ref, iface_ref, idx);
6826 /* Returns the value to use for the in-charge parameter when making a
6827 call to a function with the indicated NAME.
6829 FIXME:Can't we find a neater way to do this mapping? */
6832 in_charge_arg_for_name (tree name)
6834 if (name == base_ctor_identifier
6835 || name == base_dtor_identifier)
6836 return integer_zero_node;
6837 else if (name == complete_ctor_identifier)
6838 return integer_one_node;
6839 else if (name == complete_dtor_identifier)
6840 return integer_two_node;
6841 else if (name == deleting_dtor_identifier)
6842 return integer_three_node;
6844 /* This function should only be called with one of the names listed
6850 /* Build a call to a constructor, destructor, or an assignment
6851 operator for INSTANCE, an expression with class type. NAME
6852 indicates the special member function to call; *ARGS are the
6853 arguments. ARGS may be NULL. This may change ARGS. BINFO
6854 indicates the base of INSTANCE that is to be passed as the `this'
6855 parameter to the member function called.
6857 FLAGS are the LOOKUP_* flags to use when processing the call.
6859 If NAME indicates a complete object constructor, INSTANCE may be
6860 NULL_TREE. In this case, the caller will call build_cplus_new to
6861 store the newly constructed object into a VAR_DECL. */
6864 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6865 tree binfo, int flags, tsubst_flags_t complain)
6868 /* The type of the subobject to be constructed or destroyed. */
6870 VEC(tree,gc) *allocated = NULL;
6873 gcc_assert (name == complete_ctor_identifier
6874 || name == base_ctor_identifier
6875 || name == complete_dtor_identifier
6876 || name == base_dtor_identifier
6877 || name == deleting_dtor_identifier
6878 || name == ansi_assopname (NOP_EXPR));
6881 /* Resolve the name. */
6882 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
6883 return error_mark_node;
6885 binfo = TYPE_BINFO (binfo);
6888 gcc_assert (binfo != NULL_TREE);
6890 class_type = BINFO_TYPE (binfo);
6892 /* Handle the special case where INSTANCE is NULL_TREE. */
6893 if (name == complete_ctor_identifier && !instance)
6895 instance = build_int_cst (build_pointer_type (class_type), 0);
6896 instance = build1 (INDIRECT_REF, class_type, instance);
6900 if (name == complete_dtor_identifier
6901 || name == base_dtor_identifier
6902 || name == deleting_dtor_identifier)
6903 gcc_assert (args == NULL || VEC_empty (tree, *args));
6905 /* Convert to the base class, if necessary. */
6906 if (!same_type_ignoring_top_level_qualifiers_p
6907 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6909 if (name != ansi_assopname (NOP_EXPR))
6910 /* For constructors and destructors, either the base is
6911 non-virtual, or it is virtual but we are doing the
6912 conversion from a constructor or destructor for the
6913 complete object. In either case, we can convert
6915 instance = convert_to_base_statically (instance, binfo);
6917 /* However, for assignment operators, we must convert
6918 dynamically if the base is virtual. */
6919 instance = build_base_path (PLUS_EXPR, instance,
6920 binfo, /*nonnull=*/1, complain);
6924 gcc_assert (instance != NULL_TREE);
6926 fns = lookup_fnfields (binfo, name, 1);
6928 /* When making a call to a constructor or destructor for a subobject
6929 that uses virtual base classes, pass down a pointer to a VTT for
6931 if ((name == base_ctor_identifier
6932 || name == base_dtor_identifier)
6933 && CLASSTYPE_VBASECLASSES (class_type))
6938 /* If the current function is a complete object constructor
6939 or destructor, then we fetch the VTT directly.
6940 Otherwise, we look it up using the VTT we were given. */
6941 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6942 vtt = decay_conversion (vtt);
6943 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6944 build2 (EQ_EXPR, boolean_type_node,
6945 current_in_charge_parm, integer_zero_node),
6948 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6949 sub_vtt = fold_build_pointer_plus (vtt, BINFO_SUBVTT_INDEX (binfo));
6953 allocated = make_tree_vector ();
6957 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6960 ret = build_new_method_call (instance, fns, args,
6961 TYPE_BINFO (BINFO_TYPE (binfo)),
6965 if (allocated != NULL)
6966 release_tree_vector (allocated);
6971 /* Return the NAME, as a C string. The NAME indicates a function that
6972 is a member of TYPE. *FREE_P is set to true if the caller must
6973 free the memory returned.
6975 Rather than go through all of this, we should simply set the names
6976 of constructors and destructors appropriately, and dispense with
6977 ctor_identifier, dtor_identifier, etc. */
6980 name_as_c_string (tree name, tree type, bool *free_p)
6984 /* Assume that we will not allocate memory. */
6986 /* Constructors and destructors are special. */
6987 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6990 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6991 /* For a destructor, add the '~'. */
6992 if (name == complete_dtor_identifier
6993 || name == base_dtor_identifier
6994 || name == deleting_dtor_identifier)
6996 pretty_name = concat ("~", pretty_name, NULL);
6997 /* Remember that we need to free the memory allocated. */
7001 else if (IDENTIFIER_TYPENAME_P (name))
7003 pretty_name = concat ("operator ",
7004 type_as_string_translate (TREE_TYPE (name),
7005 TFF_PLAIN_IDENTIFIER),
7007 /* Remember that we need to free the memory allocated. */
7011 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
7016 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
7017 be set, upon return, to the function called. ARGS may be NULL.
7018 This may change ARGS. */
7021 build_new_method_call_1 (tree instance, tree fns, VEC(tree,gc) **args,
7022 tree conversion_path, int flags,
7023 tree *fn_p, tsubst_flags_t complain)
7025 struct z_candidate *candidates = 0, *cand;
7026 tree explicit_targs = NULL_TREE;
7027 tree basetype = NULL_TREE;
7030 tree first_mem_arg = NULL_TREE;
7033 bool skip_first_for_error;
7034 VEC(tree,gc) *user_args;
7037 int template_only = 0;
7041 VEC(tree,gc) *orig_args = NULL;
7044 gcc_assert (instance != NULL_TREE);
7046 /* We don't know what function we're going to call, yet. */
7050 if (error_operand_p (instance)
7051 || !fns || error_operand_p (fns))
7052 return error_mark_node;
7054 if (!BASELINK_P (fns))
7056 if (complain & tf_error)
7057 error ("call to non-function %qD", fns);
7058 return error_mark_node;
7061 orig_instance = instance;
7064 /* Dismantle the baselink to collect all the information we need. */
7065 if (!conversion_path)
7066 conversion_path = BASELINK_BINFO (fns);
7067 access_binfo = BASELINK_ACCESS_BINFO (fns);
7068 optype = BASELINK_OPTYPE (fns);
7069 fns = BASELINK_FUNCTIONS (fns);
7070 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7072 explicit_targs = TREE_OPERAND (fns, 1);
7073 fns = TREE_OPERAND (fns, 0);
7076 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
7077 || TREE_CODE (fns) == TEMPLATE_DECL
7078 || TREE_CODE (fns) == OVERLOAD);
7079 fn = get_first_fn (fns);
7080 name = DECL_NAME (fn);
7082 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
7083 gcc_assert (CLASS_TYPE_P (basetype));
7085 if (processing_template_decl)
7087 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
7088 instance = build_non_dependent_expr (instance);
7090 make_args_non_dependent (*args);
7093 user_args = args == NULL ? NULL : *args;
7094 /* Under DR 147 A::A() is an invalid constructor call,
7095 not a functional cast. */
7096 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
7098 if (! (complain & tf_error))
7099 return error_mark_node;
7101 permerror (input_location,
7102 "cannot call constructor %<%T::%D%> directly",
7104 permerror (input_location, " for a function-style cast, remove the "
7105 "redundant %<::%D%>", name);
7106 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
7111 /* Figure out whether to skip the first argument for the error
7112 message we will display to users if an error occurs. We don't
7113 want to display any compiler-generated arguments. The "this"
7114 pointer hasn't been added yet. However, we must remove the VTT
7115 pointer if this is a call to a base-class constructor or
7117 skip_first_for_error = false;
7118 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7120 /* Callers should explicitly indicate whether they want to construct
7121 the complete object or just the part without virtual bases. */
7122 gcc_assert (name != ctor_identifier);
7123 /* Similarly for destructors. */
7124 gcc_assert (name != dtor_identifier);
7125 /* Remove the VTT pointer, if present. */
7126 if ((name == base_ctor_identifier || name == base_dtor_identifier)
7127 && CLASSTYPE_VBASECLASSES (basetype))
7128 skip_first_for_error = true;
7131 /* Process the argument list. */
7132 if (args != NULL && *args != NULL)
7134 *args = resolve_args (*args, complain);
7136 return error_mark_node;
7139 instance_ptr = build_this (instance);
7141 /* It's OK to call destructors and constructors on cv-qualified objects.
7142 Therefore, convert the INSTANCE_PTR to the unqualified type, if
7144 if (DECL_DESTRUCTOR_P (fn)
7145 || DECL_CONSTRUCTOR_P (fn))
7147 tree type = build_pointer_type (basetype);
7148 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
7149 instance_ptr = build_nop (type, instance_ptr);
7151 if (DECL_DESTRUCTOR_P (fn))
7152 name = complete_dtor_identifier;
7154 first_mem_arg = instance_ptr;
7156 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7157 p = conversion_obstack_alloc (0);
7159 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
7160 initializer, not T({ }). */
7161 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
7162 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
7163 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0)))
7165 tree init_list = VEC_index (tree, *args, 0);
7167 gcc_assert (VEC_length (tree, *args) == 1
7168 && !(flags & LOOKUP_ONLYCONVERTING));
7170 /* If the initializer list has no elements and T is a class type with
7171 a default constructor, the object is value-initialized. Handle
7172 this here so we don't need to handle it wherever we use
7173 build_special_member_call. */
7174 if (CONSTRUCTOR_NELTS (init_list) == 0
7175 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
7176 && !processing_template_decl)
7178 tree ob, init = build_value_init (basetype, complain);
7179 if (integer_zerop (instance_ptr))
7180 return get_target_expr_sfinae (init, complain);
7181 ob = build_fold_indirect_ref (instance_ptr);
7182 init = build2 (INIT_EXPR, TREE_TYPE (ob), ob, init);
7183 TREE_SIDE_EFFECTS (init) = true;
7187 add_list_candidates (fns, first_mem_arg, init_list,
7188 basetype, explicit_targs, template_only,
7189 conversion_path, access_binfo, flags, &candidates);
7193 add_candidates (fns, first_mem_arg, user_args, optype,
7194 explicit_targs, template_only, conversion_path,
7195 access_binfo, flags, &candidates);
7197 any_viable_p = false;
7198 candidates = splice_viable (candidates, pedantic, &any_viable_p);
7202 if (complain & tf_error)
7204 if (!COMPLETE_OR_OPEN_TYPE_P (basetype))
7205 cxx_incomplete_type_error (instance_ptr, basetype);
7207 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
7208 basetype, optype, build_tree_list_vec (user_args),
7209 TREE_TYPE (TREE_TYPE (instance_ptr)));
7216 pretty_name = name_as_c_string (name, basetype, &free_p);
7217 arglist = build_tree_list_vec (user_args);
7218 if (skip_first_for_error)
7219 arglist = TREE_CHAIN (arglist);
7220 error ("no matching function for call to %<%T::%s(%A)%#V%>",
7221 basetype, pretty_name, arglist,
7222 TREE_TYPE (TREE_TYPE (instance_ptr)));
7226 print_z_candidates (location_of (name), candidates);
7228 call = error_mark_node;
7232 cand = tourney (candidates);
7239 if (complain & tf_error)
7241 pretty_name = name_as_c_string (name, basetype, &free_p);
7242 arglist = build_tree_list_vec (user_args);
7243 if (skip_first_for_error)
7244 arglist = TREE_CHAIN (arglist);
7245 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
7247 print_z_candidates (location_of (name), candidates);
7251 call = error_mark_node;
7257 if (!(flags & LOOKUP_NONVIRTUAL)
7258 && DECL_PURE_VIRTUAL_P (fn)
7259 && instance == current_class_ref
7260 && (DECL_CONSTRUCTOR_P (current_function_decl)
7261 || DECL_DESTRUCTOR_P (current_function_decl))
7262 && (complain & tf_warning))
7263 /* This is not an error, it is runtime undefined
7265 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
7266 "pure virtual %q#D called from constructor"
7267 : "pure virtual %q#D called from destructor"),
7270 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
7271 && is_dummy_object (instance_ptr))
7273 if (complain & tf_error)
7274 error ("cannot call member function %qD without object",
7276 call = error_mark_node;
7280 /* Optimize away vtable lookup if we know that this function
7281 can't be overridden. */
7282 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
7283 && (resolves_to_fixed_type_p (instance, 0)
7284 || DECL_FINAL_P (fn) || CLASSTYPE_FINAL (basetype)))
7285 flags |= LOOKUP_NONVIRTUAL;
7287 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
7288 /* Now we know what function is being called. */
7291 /* Build the actual CALL_EXPR. */
7292 call = build_over_call (cand, flags, complain);
7293 /* In an expression of the form `a->f()' where `f' turns
7294 out to be a static member function, `a' is
7295 none-the-less evaluated. */
7296 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
7297 && !is_dummy_object (instance_ptr)
7298 && TREE_SIDE_EFFECTS (instance_ptr))
7299 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
7300 instance_ptr, call);
7301 else if (call != error_mark_node
7302 && DECL_DESTRUCTOR_P (cand->fn)
7303 && !VOID_TYPE_P (TREE_TYPE (call)))
7304 /* An explicit call of the form "x->~X()" has type
7305 "void". However, on platforms where destructors
7306 return "this" (i.e., those where
7307 targetm.cxx.cdtor_returns_this is true), such calls
7308 will appear to have a return value of pointer type
7309 to the low-level call machinery. We do not want to
7310 change the low-level machinery, since we want to be
7311 able to optimize "delete f()" on such platforms as
7312 "operator delete(~X(f()))" (rather than generating
7313 "t = f(), ~X(t), operator delete (t)"). */
7314 call = build_nop (void_type_node, call);
7319 if (processing_template_decl && call != error_mark_node)
7321 bool cast_to_void = false;
7323 if (TREE_CODE (call) == COMPOUND_EXPR)
7324 call = TREE_OPERAND (call, 1);
7325 else if (TREE_CODE (call) == NOP_EXPR)
7327 cast_to_void = true;
7328 call = TREE_OPERAND (call, 0);
7330 if (TREE_CODE (call) == INDIRECT_REF)
7331 call = TREE_OPERAND (call, 0);
7332 call = (build_min_non_dep_call_vec
7334 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
7335 orig_instance, orig_fns, NULL_TREE),
7337 call = convert_from_reference (call);
7339 call = build_nop (void_type_node, call);
7342 /* Free all the conversions we allocated. */
7343 obstack_free (&conversion_obstack, p);
7345 if (orig_args != NULL)
7346 release_tree_vector (orig_args);
7351 /* Wrapper for above. */
7354 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
7355 tree conversion_path, int flags,
7356 tree *fn_p, tsubst_flags_t complain)
7359 bool subtime = timevar_cond_start (TV_OVERLOAD);
7360 ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags,
7362 timevar_cond_stop (TV_OVERLOAD, subtime);
7366 /* Returns true iff standard conversion sequence ICS1 is a proper
7367 subsequence of ICS2. */
7370 is_subseq (conversion *ics1, conversion *ics2)
7372 /* We can assume that a conversion of the same code
7373 between the same types indicates a subsequence since we only get
7374 here if the types we are converting from are the same. */
7376 while (ics1->kind == ck_rvalue
7377 || ics1->kind == ck_lvalue)
7378 ics1 = ics1->u.next;
7382 while (ics2->kind == ck_rvalue
7383 || ics2->kind == ck_lvalue)
7384 ics2 = ics2->u.next;
7386 if (ics2->kind == ck_user
7387 || ics2->kind == ck_ambig
7388 || ics2->kind == ck_aggr
7389 || ics2->kind == ck_list
7390 || ics2->kind == ck_identity)
7391 /* At this point, ICS1 cannot be a proper subsequence of
7392 ICS2. We can get a USER_CONV when we are comparing the
7393 second standard conversion sequence of two user conversion
7397 ics2 = ics2->u.next;
7399 if (ics2->kind == ics1->kind
7400 && same_type_p (ics2->type, ics1->type)
7401 && same_type_p (ics2->u.next->type,
7402 ics1->u.next->type))
7407 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
7408 be any _TYPE nodes. */
7411 is_properly_derived_from (tree derived, tree base)
7413 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
7416 /* We only allow proper derivation here. The DERIVED_FROM_P macro
7417 considers every class derived from itself. */
7418 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
7419 && DERIVED_FROM_P (base, derived));
7422 /* We build the ICS for an implicit object parameter as a pointer
7423 conversion sequence. However, such a sequence should be compared
7424 as if it were a reference conversion sequence. If ICS is the
7425 implicit conversion sequence for an implicit object parameter,
7426 modify it accordingly. */
7429 maybe_handle_implicit_object (conversion **ics)
7433 /* [over.match.funcs]
7435 For non-static member functions, the type of the
7436 implicit object parameter is "reference to cv X"
7437 where X is the class of which the function is a
7438 member and cv is the cv-qualification on the member
7439 function declaration. */
7440 conversion *t = *ics;
7441 tree reference_type;
7443 /* The `this' parameter is a pointer to a class type. Make the
7444 implicit conversion talk about a reference to that same class
7446 reference_type = TREE_TYPE (t->type);
7447 reference_type = build_reference_type (reference_type);
7449 if (t->kind == ck_qual)
7451 if (t->kind == ck_ptr)
7453 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
7454 t = direct_reference_binding (reference_type, t);
7456 t->rvaluedness_matches_p = 0;
7461 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
7462 and return the initial reference binding conversion. Otherwise,
7463 leave *ICS unchanged and return NULL. */
7466 maybe_handle_ref_bind (conversion **ics)
7468 if ((*ics)->kind == ck_ref_bind)
7470 conversion *old_ics = *ics;
7471 *ics = old_ics->u.next;
7472 (*ics)->user_conv_p = old_ics->user_conv_p;
7479 /* Compare two implicit conversion sequences according to the rules set out in
7480 [over.ics.rank]. Return values:
7482 1: ics1 is better than ics2
7483 -1: ics2 is better than ics1
7484 0: ics1 and ics2 are indistinguishable */
7487 compare_ics (conversion *ics1, conversion *ics2)
7493 tree deref_from_type1 = NULL_TREE;
7494 tree deref_from_type2 = NULL_TREE;
7495 tree deref_to_type1 = NULL_TREE;
7496 tree deref_to_type2 = NULL_TREE;
7497 conversion_rank rank1, rank2;
7499 /* REF_BINDING is nonzero if the result of the conversion sequence
7500 is a reference type. In that case REF_CONV is the reference
7501 binding conversion. */
7502 conversion *ref_conv1;
7503 conversion *ref_conv2;
7505 /* Handle implicit object parameters. */
7506 maybe_handle_implicit_object (&ics1);
7507 maybe_handle_implicit_object (&ics2);
7509 /* Handle reference parameters. */
7510 ref_conv1 = maybe_handle_ref_bind (&ics1);
7511 ref_conv2 = maybe_handle_ref_bind (&ics2);
7513 /* List-initialization sequence L1 is a better conversion sequence than
7514 list-initialization sequence L2 if L1 converts to
7515 std::initializer_list<X> for some X and L2 does not. */
7516 if (ics1->kind == ck_list && ics2->kind != ck_list)
7518 if (ics2->kind == ck_list && ics1->kind != ck_list)
7523 When comparing the basic forms of implicit conversion sequences (as
7524 defined in _over.best.ics_)
7526 --a standard conversion sequence (_over.ics.scs_) is a better
7527 conversion sequence than a user-defined conversion sequence
7528 or an ellipsis conversion sequence, and
7530 --a user-defined conversion sequence (_over.ics.user_) is a
7531 better conversion sequence than an ellipsis conversion sequence
7532 (_over.ics.ellipsis_). */
7533 rank1 = CONVERSION_RANK (ics1);
7534 rank2 = CONVERSION_RANK (ics2);
7538 else if (rank1 < rank2)
7541 if (rank1 == cr_bad)
7543 /* Both ICS are bad. We try to make a decision based on what would
7544 have happened if they'd been good. This is not an extension,
7545 we'll still give an error when we build up the call; this just
7546 helps us give a more helpful error message. */
7547 rank1 = BAD_CONVERSION_RANK (ics1);
7548 rank2 = BAD_CONVERSION_RANK (ics2);
7552 else if (rank1 < rank2)
7555 /* We couldn't make up our minds; try to figure it out below. */
7558 if (ics1->ellipsis_p)
7559 /* Both conversions are ellipsis conversions. */
7562 /* User-defined conversion sequence U1 is a better conversion sequence
7563 than another user-defined conversion sequence U2 if they contain the
7564 same user-defined conversion operator or constructor and if the sec-
7565 ond standard conversion sequence of U1 is better than the second
7566 standard conversion sequence of U2. */
7568 /* Handle list-conversion with the same code even though it isn't always
7569 ranked as a user-defined conversion and it doesn't have a second
7570 standard conversion sequence; it will still have the desired effect.
7571 Specifically, we need to do the reference binding comparison at the
7572 end of this function. */
7574 if (ics1->user_conv_p || ics1->kind == ck_list)
7579 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
7580 if (t1->kind == ck_ambig || t1->kind == ck_aggr
7581 || t1->kind == ck_list)
7583 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
7584 if (t2->kind == ck_ambig || t2->kind == ck_aggr
7585 || t2->kind == ck_list)
7588 if (t1->kind != t2->kind)
7590 else if (t1->kind == ck_user)
7592 if (t1->cand->fn != t2->cand->fn)
7597 /* For ambiguous or aggregate conversions, use the target type as
7598 a proxy for the conversion function. */
7599 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
7603 /* We can just fall through here, after setting up
7604 FROM_TYPE1 and FROM_TYPE2. */
7605 from_type1 = t1->type;
7606 from_type2 = t2->type;
7613 /* We're dealing with two standard conversion sequences.
7617 Standard conversion sequence S1 is a better conversion
7618 sequence than standard conversion sequence S2 if
7620 --S1 is a proper subsequence of S2 (comparing the conversion
7621 sequences in the canonical form defined by _over.ics.scs_,
7622 excluding any Lvalue Transformation; the identity
7623 conversion sequence is considered to be a subsequence of
7624 any non-identity conversion sequence */
7627 while (t1->kind != ck_identity)
7629 from_type1 = t1->type;
7632 while (t2->kind != ck_identity)
7634 from_type2 = t2->type;
7637 /* One sequence can only be a subsequence of the other if they start with
7638 the same type. They can start with different types when comparing the
7639 second standard conversion sequence in two user-defined conversion
7641 if (same_type_p (from_type1, from_type2))
7643 if (is_subseq (ics1, ics2))
7645 if (is_subseq (ics2, ics1))
7653 --the rank of S1 is better than the rank of S2 (by the rules
7656 Standard conversion sequences are ordered by their ranks: an Exact
7657 Match is a better conversion than a Promotion, which is a better
7658 conversion than a Conversion.
7660 Two conversion sequences with the same rank are indistinguishable
7661 unless one of the following rules applies:
7663 --A conversion that does not a convert a pointer, pointer to member,
7664 or std::nullptr_t to bool is better than one that does.
7666 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
7667 so that we do not have to check it explicitly. */
7668 if (ics1->rank < ics2->rank)
7670 else if (ics2->rank < ics1->rank)
7673 to_type1 = ics1->type;
7674 to_type2 = ics2->type;
7676 /* A conversion from scalar arithmetic type to complex is worse than a
7677 conversion between scalar arithmetic types. */
7678 if (same_type_p (from_type1, from_type2)
7679 && ARITHMETIC_TYPE_P (from_type1)
7680 && ARITHMETIC_TYPE_P (to_type1)
7681 && ARITHMETIC_TYPE_P (to_type2)
7682 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
7683 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
7685 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
7691 if (TYPE_PTR_P (from_type1)
7692 && TYPE_PTR_P (from_type2)
7693 && TYPE_PTR_P (to_type1)
7694 && TYPE_PTR_P (to_type2))
7696 deref_from_type1 = TREE_TYPE (from_type1);
7697 deref_from_type2 = TREE_TYPE (from_type2);
7698 deref_to_type1 = TREE_TYPE (to_type1);
7699 deref_to_type2 = TREE_TYPE (to_type2);
7701 /* The rules for pointers to members A::* are just like the rules
7702 for pointers A*, except opposite: if B is derived from A then
7703 A::* converts to B::*, not vice versa. For that reason, we
7704 switch the from_ and to_ variables here. */
7705 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
7706 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
7707 || (TYPE_PTRMEMFUNC_P (from_type1)
7708 && TYPE_PTRMEMFUNC_P (from_type2)
7709 && TYPE_PTRMEMFUNC_P (to_type1)
7710 && TYPE_PTRMEMFUNC_P (to_type2)))
7712 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
7713 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
7714 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
7715 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
7718 if (deref_from_type1 != NULL_TREE
7719 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
7720 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
7722 /* This was one of the pointer or pointer-like conversions.
7726 --If class B is derived directly or indirectly from class A,
7727 conversion of B* to A* is better than conversion of B* to
7728 void*, and conversion of A* to void* is better than
7729 conversion of B* to void*. */
7730 if (TREE_CODE (deref_to_type1) == VOID_TYPE
7731 && TREE_CODE (deref_to_type2) == VOID_TYPE)
7733 if (is_properly_derived_from (deref_from_type1,
7736 else if (is_properly_derived_from (deref_from_type2,
7740 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
7741 || TREE_CODE (deref_to_type2) == VOID_TYPE)
7743 if (same_type_p (deref_from_type1, deref_from_type2))
7745 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
7747 if (is_properly_derived_from (deref_from_type1,
7751 /* We know that DEREF_TO_TYPE1 is `void' here. */
7752 else if (is_properly_derived_from (deref_from_type1,
7757 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
7758 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
7762 --If class B is derived directly or indirectly from class A
7763 and class C is derived directly or indirectly from B,
7765 --conversion of C* to B* is better than conversion of C* to
7768 --conversion of B* to A* is better than conversion of C* to
7770 if (same_type_p (deref_from_type1, deref_from_type2))
7772 if (is_properly_derived_from (deref_to_type1,
7775 else if (is_properly_derived_from (deref_to_type2,
7779 else if (same_type_p (deref_to_type1, deref_to_type2))
7781 if (is_properly_derived_from (deref_from_type2,
7784 else if (is_properly_derived_from (deref_from_type1,
7790 else if (CLASS_TYPE_P (non_reference (from_type1))
7791 && same_type_p (from_type1, from_type2))
7793 tree from = non_reference (from_type1);
7797 --binding of an expression of type C to a reference of type
7798 B& is better than binding an expression of type C to a
7799 reference of type A&
7801 --conversion of C to B is better than conversion of C to A, */
7802 if (is_properly_derived_from (from, to_type1)
7803 && is_properly_derived_from (from, to_type2))
7805 if (is_properly_derived_from (to_type1, to_type2))
7807 else if (is_properly_derived_from (to_type2, to_type1))
7811 else if (CLASS_TYPE_P (non_reference (to_type1))
7812 && same_type_p (to_type1, to_type2))
7814 tree to = non_reference (to_type1);
7818 --binding of an expression of type B to a reference of type
7819 A& is better than binding an expression of type C to a
7820 reference of type A&,
7822 --conversion of B to A is better than conversion of C to A */
7823 if (is_properly_derived_from (from_type1, to)
7824 && is_properly_derived_from (from_type2, to))
7826 if (is_properly_derived_from (from_type2, from_type1))
7828 else if (is_properly_derived_from (from_type1, from_type2))
7835 --S1 and S2 differ only in their qualification conversion and yield
7836 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
7837 qualification signature of type T1 is a proper subset of the cv-
7838 qualification signature of type T2 */
7839 if (ics1->kind == ck_qual
7840 && ics2->kind == ck_qual
7841 && same_type_p (from_type1, from_type2))
7843 int result = comp_cv_qual_signature (to_type1, to_type2);
7850 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
7851 to an implicit object parameter, and either S1 binds an lvalue reference
7852 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
7853 reference to an rvalue and S2 binds an lvalue reference
7854 (C++0x draft standard, 13.3.3.2)
7856 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
7857 types to which the references refer are the same type except for
7858 top-level cv-qualifiers, and the type to which the reference
7859 initialized by S2 refers is more cv-qualified than the type to
7860 which the reference initialized by S1 refers */
7862 if (ref_conv1 && ref_conv2)
7864 if (!ref_conv1->this_p && !ref_conv2->this_p)
7866 if (ref_conv1->rvaluedness_matches_p
7867 > ref_conv2->rvaluedness_matches_p)
7869 if (ref_conv2->rvaluedness_matches_p
7870 > ref_conv1->rvaluedness_matches_p)
7874 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
7875 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
7876 TREE_TYPE (ref_conv1->type));
7879 /* Neither conversion sequence is better than the other. */
7883 /* The source type for this standard conversion sequence. */
7886 source_type (conversion *t)
7888 for (;; t = t->u.next)
7890 if (t->kind == ck_user
7891 || t->kind == ck_ambig
7892 || t->kind == ck_identity)
7898 /* Note a warning about preferring WINNER to LOSER. We do this by storing
7899 a pointer to LOSER and re-running joust to produce the warning if WINNER
7900 is actually used. */
7903 add_warning (struct z_candidate *winner, struct z_candidate *loser)
7905 candidate_warning *cw = (candidate_warning *)
7906 conversion_obstack_alloc (sizeof (candidate_warning));
7908 cw->next = winner->warnings;
7909 winner->warnings = cw;
7912 /* Compare two candidates for overloading as described in
7913 [over.match.best]. Return values:
7915 1: cand1 is better than cand2
7916 -1: cand2 is better than cand1
7917 0: cand1 and cand2 are indistinguishable */
7920 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7923 int off1 = 0, off2 = 0;
7927 /* Candidates that involve bad conversions are always worse than those
7929 if (cand1->viable > cand2->viable)
7931 if (cand1->viable < cand2->viable)
7934 /* If we have two pseudo-candidates for conversions to the same type,
7935 or two candidates for the same function, arbitrarily pick one. */
7936 if (cand1->fn == cand2->fn
7937 && (IS_TYPE_OR_DECL_P (cand1->fn)))
7940 /* a viable function F1
7941 is defined to be a better function than another viable function F2 if
7942 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7943 ICSi(F2), and then */
7945 /* for some argument j, ICSj(F1) is a better conversion sequence than
7948 /* For comparing static and non-static member functions, we ignore
7949 the implicit object parameter of the non-static function. The
7950 standard says to pretend that the static function has an object
7951 parm, but that won't work with operator overloading. */
7952 len = cand1->num_convs;
7953 if (len != cand2->num_convs)
7955 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
7956 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
7958 gcc_assert (static_1 != static_2);
7969 for (i = 0; i < len; ++i)
7971 conversion *t1 = cand1->convs[i + off1];
7972 conversion *t2 = cand2->convs[i + off2];
7973 int comp = compare_ics (t1, t2);
7978 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7979 == cr_std + cr_promotion)
7980 && t1->kind == ck_std
7981 && t2->kind == ck_std
7982 && TREE_CODE (t1->type) == INTEGER_TYPE
7983 && TREE_CODE (t2->type) == INTEGER_TYPE
7984 && (TYPE_PRECISION (t1->type)
7985 == TYPE_PRECISION (t2->type))
7986 && (TYPE_UNSIGNED (t1->u.next->type)
7987 || (TREE_CODE (t1->u.next->type)
7990 tree type = t1->u.next->type;
7992 struct z_candidate *w, *l;
7994 type1 = t1->type, type2 = t2->type,
7995 w = cand1, l = cand2;
7997 type1 = t2->type, type2 = t1->type,
7998 w = cand2, l = cand1;
8002 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
8003 type, type1, type2);
8004 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
8010 if (winner && comp != winner)
8019 /* warn about confusing overload resolution for user-defined conversions,
8020 either between a constructor and a conversion op, or between two
8022 if (winner && warn_conversion && cand1->second_conv
8023 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
8024 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
8026 struct z_candidate *w, *l;
8027 bool give_warning = false;
8030 w = cand1, l = cand2;
8032 w = cand2, l = cand1;
8034 /* We don't want to complain about `X::operator T1 ()'
8035 beating `X::operator T2 () const', when T2 is a no less
8036 cv-qualified version of T1. */
8037 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
8038 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
8040 tree t = TREE_TYPE (TREE_TYPE (l->fn));
8041 tree f = TREE_TYPE (TREE_TYPE (w->fn));
8043 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
8048 if (!comp_ptr_ttypes (t, f))
8049 give_warning = true;
8052 give_warning = true;
8058 tree source = source_type (w->convs[0]);
8059 if (! DECL_CONSTRUCTOR_P (w->fn))
8060 source = TREE_TYPE (source);
8061 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
8062 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
8063 source, w->second_conv->type))
8065 inform (input_location, " because conversion sequence for the argument is better");
8076 F1 is a non-template function and F2 is a template function
8079 if (!cand1->template_decl && cand2->template_decl)
8081 else if (cand1->template_decl && !cand2->template_decl)
8085 F1 and F2 are template functions and the function template for F1 is
8086 more specialized than the template for F2 according to the partial
8089 if (cand1->template_decl && cand2->template_decl)
8091 winner = more_specialized_fn
8092 (TI_TEMPLATE (cand1->template_decl),
8093 TI_TEMPLATE (cand2->template_decl),
8094 /* [temp.func.order]: The presence of unused ellipsis and default
8095 arguments has no effect on the partial ordering of function
8096 templates. add_function_candidate() will not have
8097 counted the "this" argument for constructors. */
8098 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
8104 the context is an initialization by user-defined conversion (see
8105 _dcl.init_ and _over.match.user_) and the standard conversion
8106 sequence from the return type of F1 to the destination type (i.e.,
8107 the type of the entity being initialized) is a better conversion
8108 sequence than the standard conversion sequence from the return type
8109 of F2 to the destination type. */
8111 if (cand1->second_conv)
8113 winner = compare_ics (cand1->second_conv, cand2->second_conv);
8118 /* Check whether we can discard a builtin candidate, either because we
8119 have two identical ones or matching builtin and non-builtin candidates.
8121 (Pedantically in the latter case the builtin which matched the user
8122 function should not be added to the overload set, but we spot it here.
8125 ... the builtin candidates include ...
8126 - do not have the same parameter type list as any non-template
8127 non-member candidate. */
8129 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
8130 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
8132 for (i = 0; i < len; ++i)
8133 if (!same_type_p (cand1->convs[i]->type,
8134 cand2->convs[i]->type))
8136 if (i == cand1->num_convs)
8138 if (cand1->fn == cand2->fn)
8139 /* Two built-in candidates; arbitrarily pick one. */
8141 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
8142 /* cand1 is built-in; prefer cand2. */
8145 /* cand2 is built-in; prefer cand1. */
8150 /* If the two function declarations represent the same function (this can
8151 happen with declarations in multiple scopes and arg-dependent lookup),
8152 arbitrarily choose one. But first make sure the default args we're
8154 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
8155 && equal_functions (cand1->fn, cand2->fn))
8157 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
8158 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
8160 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
8162 for (i = 0; i < len; ++i)
8164 /* Don't crash if the fn is variadic. */
8167 parms1 = TREE_CHAIN (parms1);
8168 parms2 = TREE_CHAIN (parms2);
8172 parms1 = TREE_CHAIN (parms1);
8174 parms2 = TREE_CHAIN (parms2);
8178 if (!cp_tree_equal (TREE_PURPOSE (parms1),
8179 TREE_PURPOSE (parms2)))
8183 permerror (input_location, "default argument mismatch in "
8184 "overload resolution");
8185 inform (input_location,
8186 " candidate 1: %q+#F", cand1->fn);
8187 inform (input_location,
8188 " candidate 2: %q+#F", cand2->fn);
8191 add_warning (cand1, cand2);
8194 parms1 = TREE_CHAIN (parms1);
8195 parms2 = TREE_CHAIN (parms2);
8203 /* Extension: If the worst conversion for one candidate is worse than the
8204 worst conversion for the other, take the first. */
8207 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
8208 struct z_candidate *w = 0, *l = 0;
8210 for (i = 0; i < len; ++i)
8212 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
8213 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
8214 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
8215 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
8218 winner = 1, w = cand1, l = cand2;
8220 winner = -1, w = cand2, l = cand1;
8223 /* Don't choose a deleted function over ambiguity. */
8224 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
8228 pedwarn (input_location, 0,
8229 "ISO C++ says that these are ambiguous, even "
8230 "though the worst conversion for the first is better than "
8231 "the worst conversion for the second:");
8232 print_z_candidate (_("candidate 1:"), w);
8233 print_z_candidate (_("candidate 2:"), l);
8241 gcc_assert (!winner);
8245 /* Given a list of candidates for overloading, find the best one, if any.
8246 This algorithm has a worst case of O(2n) (winner is last), and a best
8247 case of O(n/2) (totally ambiguous); much better than a sorting
8250 static struct z_candidate *
8251 tourney (struct z_candidate *candidates)
8253 struct z_candidate *champ = candidates, *challenger;
8255 int champ_compared_to_predecessor = 0;
8257 /* Walk through the list once, comparing each current champ to the next
8258 candidate, knocking out a candidate or two with each comparison. */
8260 for (challenger = champ->next; challenger; )
8262 fate = joust (champ, challenger, 0);
8264 challenger = challenger->next;
8269 champ = challenger->next;
8272 champ_compared_to_predecessor = 0;
8277 champ_compared_to_predecessor = 1;
8280 challenger = champ->next;
8284 /* Make sure the champ is better than all the candidates it hasn't yet
8285 been compared to. */
8287 for (challenger = candidates;
8289 && !(champ_compared_to_predecessor && challenger->next == champ);
8290 challenger = challenger->next)
8292 fate = joust (champ, challenger, 0);
8300 /* Returns nonzero if things of type FROM can be converted to TO. */
8303 can_convert (tree to, tree from)
8305 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
8308 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
8311 can_convert_arg (tree to, tree from, tree arg, int flags)
8317 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8318 p = conversion_obstack_alloc (0);
8320 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8322 ok_p = (t && !t->bad_p);
8324 /* Free all the conversions we allocated. */
8325 obstack_free (&conversion_obstack, p);
8330 /* Like can_convert_arg, but allows dubious conversions as well. */
8333 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
8338 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8339 p = conversion_obstack_alloc (0);
8340 /* Try to perform the conversion. */
8341 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8343 /* Free all the conversions we allocated. */
8344 obstack_free (&conversion_obstack, p);
8349 /* Convert EXPR to TYPE. Return the converted expression.
8351 Note that we allow bad conversions here because by the time we get to
8352 this point we are committed to doing the conversion. If we end up
8353 doing a bad conversion, convert_like will complain. */
8356 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
8361 if (error_operand_p (expr))
8362 return error_mark_node;
8364 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8365 p = conversion_obstack_alloc (0);
8367 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8373 if (complain & tf_error)
8375 /* If expr has unknown type, then it is an overloaded function.
8376 Call instantiate_type to get good error messages. */
8377 if (TREE_TYPE (expr) == unknown_type_node)
8378 instantiate_type (type, expr, complain);
8379 else if (invalid_nonstatic_memfn_p (expr, complain))
8380 /* We gave an error. */;
8382 error ("could not convert %qE from %qT to %qT", expr,
8383 TREE_TYPE (expr), type);
8385 expr = error_mark_node;
8387 else if (processing_template_decl)
8389 /* In a template, we are only concerned about determining the
8390 type of non-dependent expressions, so we do not have to
8391 perform the actual conversion. */
8392 if (TREE_TYPE (expr) != type)
8393 expr = build_nop (type, expr);
8396 expr = convert_like (conv, expr, complain);
8398 /* Free all the conversions we allocated. */
8399 obstack_free (&conversion_obstack, p);
8405 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
8407 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
8410 /* Convert EXPR to TYPE (as a direct-initialization) if that is
8411 permitted. If the conversion is valid, the converted expression is
8412 returned. Otherwise, NULL_TREE is returned, except in the case
8413 that TYPE is a class type; in that case, an error is issued. If
8414 C_CAST_P is true, then this direct-initialization is taking
8415 place as part of a static_cast being attempted as part of a C-style
8419 perform_direct_initialization_if_possible (tree type,
8422 tsubst_flags_t complain)
8427 if (type == error_mark_node || error_operand_p (expr))
8428 return error_mark_node;
8431 If the destination type is a (possibly cv-qualified) class type:
8433 -- If the initialization is direct-initialization ...,
8434 constructors are considered. ... If no constructor applies, or
8435 the overload resolution is ambiguous, the initialization is
8437 if (CLASS_TYPE_P (type))
8439 VEC(tree,gc) *args = make_tree_vector_single (expr);
8440 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
8441 &args, type, LOOKUP_NORMAL, complain);
8442 release_tree_vector (args);
8443 return build_cplus_new (type, expr, complain);
8446 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8447 p = conversion_obstack_alloc (0);
8449 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8452 if (!conv || conv->bad_p)
8455 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
8456 /*issue_conversion_warnings=*/false,
8460 /* Free all the conversions we allocated. */
8461 obstack_free (&conversion_obstack, p);
8466 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
8467 is being bound to a temporary. Create and return a new VAR_DECL
8468 with the indicated TYPE; this variable will store the value to
8469 which the reference is bound. */
8472 make_temporary_var_for_ref_to_temp (tree decl, tree type)
8476 /* Create the variable. */
8477 var = create_temporary_var (type);
8479 /* Register the variable. */
8480 if (TREE_STATIC (decl))
8482 /* Namespace-scope or local static; give it a mangled name. */
8485 TREE_STATIC (var) = 1;
8486 name = mangle_ref_init_variable (decl);
8487 DECL_NAME (var) = name;
8488 SET_DECL_ASSEMBLER_NAME (var, name);
8489 var = pushdecl_top_level (var);
8492 /* Create a new cleanup level if necessary. */
8493 maybe_push_cleanup_level (type);
8498 /* EXPR is the initializer for a variable DECL of reference or
8499 std::initializer_list type. Create, push and return a new VAR_DECL
8500 for the initializer so that it will live as long as DECL. Any
8501 cleanup for the new variable is returned through CLEANUP, and the
8502 code to initialize the new variable is returned through INITP. */
8505 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
8511 /* Create the temporary variable. */
8512 type = TREE_TYPE (expr);
8513 var = make_temporary_var_for_ref_to_temp (decl, type);
8514 layout_decl (var, 0);
8515 /* If the rvalue is the result of a function call it will be
8516 a TARGET_EXPR. If it is some other construct (such as a
8517 member access expression where the underlying object is
8518 itself the result of a function call), turn it into a
8519 TARGET_EXPR here. It is important that EXPR be a
8520 TARGET_EXPR below since otherwise the INIT_EXPR will
8521 attempt to make a bitwise copy of EXPR to initialize
8523 if (TREE_CODE (expr) != TARGET_EXPR)
8524 expr = get_target_expr (expr);
8526 /* If the initializer is constant, put it in DECL_INITIAL so we get
8527 static initialization and use in constant expressions. */
8528 init = maybe_constant_init (expr);
8529 if (TREE_CONSTANT (init))
8531 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
8533 /* 5.19 says that a constant expression can include an
8534 lvalue-rvalue conversion applied to "a glvalue of literal type
8535 that refers to a non-volatile temporary object initialized
8536 with a constant expression". Rather than try to communicate
8537 that this VAR_DECL is a temporary, just mark it constexpr.
8539 Currently this is only useful for initializer_list temporaries,
8540 since reference vars can't appear in constant expressions. */
8541 DECL_DECLARED_CONSTEXPR_P (var) = true;
8542 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
8543 TREE_CONSTANT (var) = true;
8545 DECL_INITIAL (var) = init;
8549 /* Create the INIT_EXPR that will initialize the temporary
8551 init = build2 (INIT_EXPR, type, var, expr);
8552 if (at_function_scope_p ())
8554 add_decl_expr (var);
8556 if (TREE_STATIC (var))
8557 init = add_stmt_to_compound (init, register_dtor_fn (var));
8559 *cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error);
8561 /* We must be careful to destroy the temporary only
8562 after its initialization has taken place. If the
8563 initialization throws an exception, then the
8564 destructor should not be run. We cannot simply
8565 transform INIT into something like:
8567 (INIT, ({ CLEANUP_STMT; }))
8569 because emit_local_var always treats the
8570 initializer as a full-expression. Thus, the
8571 destructor would run too early; it would run at the
8572 end of initializing the reference variable, rather
8573 than at the end of the block enclosing the
8576 The solution is to pass back a cleanup expression
8577 which the caller is responsible for attaching to
8578 the statement tree. */
8582 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
8583 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
8584 static_aggregates = tree_cons (NULL_TREE, var,
8592 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
8593 initializing a variable of that TYPE. If DECL is non-NULL, it is
8594 the VAR_DECL being initialized with the EXPR. (In that case, the
8595 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
8596 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
8597 return, if *CLEANUP is no longer NULL, it will be an expression
8598 that should be pushed as a cleanup after the returned expression
8599 is used to initialize DECL.
8601 Return the converted expression. */
8604 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
8605 int flags, tsubst_flags_t complain)
8610 if (type == error_mark_node || error_operand_p (expr))
8611 return error_mark_node;
8613 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8614 p = conversion_obstack_alloc (0);
8616 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
8618 if (!conv || conv->bad_p)
8620 if (complain & tf_error)
8623 convert_like (conv, expr, complain);
8624 else if (!CP_TYPE_CONST_P (TREE_TYPE (type))
8625 && !TYPE_REF_IS_RVALUE (type)
8626 && !real_lvalue_p (expr))
8627 error ("invalid initialization of non-const reference of "
8628 "type %qT from an rvalue of type %qT",
8629 type, TREE_TYPE (expr));
8631 error ("invalid initialization of reference of type "
8632 "%qT from expression of type %qT", type,
8635 return error_mark_node;
8638 /* If DECL is non-NULL, then this special rule applies:
8642 The temporary to which the reference is bound or the temporary
8643 that is the complete object to which the reference is bound
8644 persists for the lifetime of the reference.
8646 The temporaries created during the evaluation of the expression
8647 initializing the reference, except the temporary to which the
8648 reference is bound, are destroyed at the end of the
8649 full-expression in which they are created.
8651 In that case, we store the converted expression into a new
8652 VAR_DECL in a new scope.
8654 However, we want to be careful not to create temporaries when
8655 they are not required. For example, given:
8658 struct D : public B {};
8662 there is no need to copy the return value from "f"; we can just
8663 extend its lifetime. Similarly, given:
8666 struct T { operator S(); };
8670 we can extend the lifetime of the return value of the conversion
8672 gcc_assert (conv->kind == ck_ref_bind);
8676 tree base_conv_type;
8678 gcc_assert (complain == tf_warning_or_error);
8680 /* Skip over the REF_BIND. */
8681 conv = conv->u.next;
8682 /* If the next conversion is a BASE_CONV, skip that too -- but
8683 remember that the conversion was required. */
8684 if (conv->kind == ck_base)
8686 base_conv_type = conv->type;
8687 conv = conv->u.next;
8690 base_conv_type = NULL_TREE;
8691 /* Perform the remainder of the conversion. */
8692 expr = convert_like_real (conv, expr,
8693 /*fn=*/NULL_TREE, /*argnum=*/0,
8695 /*issue_conversion_warnings=*/true,
8698 if (error_operand_p (expr))
8699 expr = error_mark_node;
8702 if (!lvalue_or_rvalue_with_address_p (expr))
8705 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
8706 /* Use its address to initialize the reference variable. */
8707 expr = build_address (var);
8709 expr = convert_to_base (expr,
8710 build_pointer_type (base_conv_type),
8711 /*check_access=*/true,
8712 /*nonnull=*/true, complain);
8714 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
8717 /* Take the address of EXPR. */
8718 expr = cp_build_addr_expr (expr, complain);
8719 /* If a BASE_CONV was required, perform it now. */
8721 expr = (perform_implicit_conversion
8722 (build_pointer_type (base_conv_type), expr,
8724 expr = build_nop (type, expr);
8728 /* Perform the conversion. */
8729 expr = convert_like (conv, expr, complain);
8731 /* Free all the conversions we allocated. */
8732 obstack_free (&conversion_obstack, p);
8737 /* Returns true iff TYPE is some variant of std::initializer_list. */
8740 is_std_init_list (tree type)
8742 /* Look through typedefs. */
8745 type = TYPE_MAIN_VARIANT (type);
8746 return (CLASS_TYPE_P (type)
8747 && CP_TYPE_CONTEXT (type) == std_node
8748 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
8751 /* Returns true iff DECL is a list constructor: i.e. a constructor which
8752 will accept an argument list of a single std::initializer_list<T>. */
8755 is_list_ctor (tree decl)
8757 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
8760 if (!args || args == void_list_node)
8763 arg = non_reference (TREE_VALUE (args));
8764 if (!is_std_init_list (arg))
8767 args = TREE_CHAIN (args);
8769 if (args && args != void_list_node && !TREE_PURPOSE (args))
8770 /* There are more non-defaulted parms. */
8776 #include "gt-cp-call.h"