1 /* Functions related to invoking -*- C++ -*- methods and overloaded functions.
2 Copyright (C) 1987-2019 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com) and
4 modified by Brendan Kehoe (brendan@cygnus.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* High-level class interface. */
27 #include "coretypes.h"
31 #include "stringpool.h"
33 #include "stor-layout.h"
34 #include "trans-mem.h"
39 #include "langhooks.h"
40 #include "c-family/c-objc.h"
41 #include "internal-fn.h"
42 #include "stringpool.h"
44 #include "gcc-rich-location.h"
46 /* The various kinds of conversion. */
48 enum conversion_kind
{
65 /* The rank of the conversion. Order of the enumerals matters; better
66 conversions should come earlier in the list. */
68 enum conversion_rank
{
79 /* An implicit conversion sequence, in the sense of [over.best.ics].
80 The first conversion to be performed is at the end of the chain.
81 That conversion is always a cr_identity conversion. */
84 /* The kind of conversion represented by this step. */
86 /* The rank of this conversion. */
88 BOOL_BITFIELD user_conv_p
: 1;
89 BOOL_BITFIELD ellipsis_p
: 1;
90 BOOL_BITFIELD this_p
: 1;
91 /* True if this conversion would be permitted with a bending of
92 language standards, e.g. disregarding pointer qualifiers or
93 converting integers to pointers. */
94 BOOL_BITFIELD bad_p
: 1;
95 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
96 temporary should be created to hold the result of the
97 conversion. If KIND is ck_ambig or ck_user, true means force
98 copy-initialization. */
99 BOOL_BITFIELD need_temporary_p
: 1;
100 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
101 from a pointer-to-derived to pointer-to-base is being performed. */
102 BOOL_BITFIELD base_p
: 1;
103 /* If KIND is ck_ref_bind, true when either an lvalue reference is
104 being bound to an lvalue expression or an rvalue reference is
105 being bound to an rvalue expression. If KIND is ck_rvalue or ck_base,
106 true when we are treating an lvalue as an rvalue (12.8p33). If
107 ck_identity, we will be binding a reference directly or decaying to
109 BOOL_BITFIELD rvaluedness_matches_p
: 1;
110 BOOL_BITFIELD check_narrowing
: 1;
111 /* Whether check_narrowing should only check TREE_CONSTANTs; used
112 in build_converted_constant_expr. */
113 BOOL_BITFIELD check_narrowing_const_only
: 1;
114 /* The type of the expression resulting from the conversion. */
117 /* The next conversion in the chain. Since the conversions are
118 arranged from outermost to innermost, the NEXT conversion will
119 actually be performed before this conversion. This variant is
120 used only when KIND is neither ck_identity, ck_ambig nor
121 ck_list. Please use the next_conversion function instead
122 of using this field directly. */
124 /* The expression at the beginning of the conversion chain. This
125 variant is used only if KIND is ck_identity or ck_ambig. */
127 /* The array of conversions for an initializer_list, so this
128 variant is used only when KIN D is ck_list. */
131 /* The function candidate corresponding to this conversion
132 sequence. This field is only used if KIND is ck_user. */
133 struct z_candidate
*cand
;
136 #define CONVERSION_RANK(NODE) \
137 ((NODE)->bad_p ? cr_bad \
138 : (NODE)->ellipsis_p ? cr_ellipsis \
139 : (NODE)->user_conv_p ? cr_user \
142 #define BAD_CONVERSION_RANK(NODE) \
143 ((NODE)->ellipsis_p ? cr_ellipsis \
144 : (NODE)->user_conv_p ? cr_user \
147 static struct obstack conversion_obstack
;
148 static bool conversion_obstack_initialized
;
149 struct rejection_reason
;
151 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
152 static int equal_functions (tree
, tree
);
153 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
155 static int compare_ics (conversion
*, conversion
*);
156 static void maybe_warn_class_memaccess (location_t
, tree
,
157 const vec
<tree
, va_gc
> *);
158 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
159 #define convert_like(CONV, EXPR, COMPLAIN) \
160 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \
161 /*issue_conversion_warnings=*/true, \
162 /*c_cast_p=*/false, (COMPLAIN))
163 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
164 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \
165 /*issue_conversion_warnings=*/true, \
166 /*c_cast_p=*/false, (COMPLAIN))
167 static tree
convert_like_real (conversion
*, tree
, tree
, int, bool,
168 bool, tsubst_flags_t
);
169 static void op_error (const op_location_t
&, enum tree_code
, enum tree_code
,
170 tree
, tree
, tree
, bool);
171 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
173 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
174 static void print_z_candidates (location_t
, struct z_candidate
*);
175 static tree
build_this (tree
);
176 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
177 static bool any_strictly_viable (struct z_candidate
*);
178 static struct z_candidate
*add_template_candidate
179 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
180 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
181 static struct z_candidate
*add_template_candidate_real
182 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
183 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
184 static void add_builtin_candidates
185 (struct z_candidate
**, enum tree_code
, enum tree_code
,
186 tree
, tree
*, int, tsubst_flags_t
);
187 static void add_builtin_candidate
188 (struct z_candidate
**, enum tree_code
, enum tree_code
,
189 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
190 static bool is_complete (tree
);
191 static void build_builtin_candidate
192 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
193 int, tsubst_flags_t
);
194 static struct z_candidate
*add_conv_candidate
195 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
196 tree
, tsubst_flags_t
);
197 static struct z_candidate
*add_function_candidate
198 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
199 tree
, int, conversion
**, tsubst_flags_t
);
200 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
202 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
204 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
205 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
206 static conversion
*next_conversion (conversion
*);
207 static bool is_subseq (conversion
*, conversion
*);
208 static conversion
*maybe_handle_ref_bind (conversion
**);
209 static void maybe_handle_implicit_object (conversion
**);
210 static struct z_candidate
*add_candidate
211 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
212 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
213 static tree
source_type (conversion
*);
214 static void add_warning (struct z_candidate
*, struct z_candidate
*);
215 static bool reference_compatible_p (tree
, tree
);
216 static conversion
*direct_reference_binding (tree
, conversion
*);
217 static bool promoted_arithmetic_type_p (tree
);
218 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
219 static char *name_as_c_string (tree
, tree
, bool *);
220 static tree
prep_operand (tree
);
221 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
222 bool, tree
, tree
, int, struct z_candidate
**,
224 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
225 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
227 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
228 NAME can take many forms... */
231 check_dtor_name (tree basetype
, tree name
)
233 /* Just accept something we've already complained about. */
234 if (name
== error_mark_node
)
237 if (TREE_CODE (name
) == TYPE_DECL
)
238 name
= TREE_TYPE (name
);
239 else if (TYPE_P (name
))
241 else if (identifier_p (name
))
243 if ((MAYBE_CLASS_TYPE_P (basetype
)
244 || TREE_CODE (basetype
) == ENUMERAL_TYPE
)
245 && name
== constructor_name (basetype
))
248 name
= get_type_value (name
);
254 template <class T> struct S { ~S(); };
258 NAME will be a class template. */
259 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
263 if (!name
|| name
== error_mark_node
)
265 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
268 /* We want the address of a function or method. We avoid creating a
269 pointer-to-member function. */
272 build_addr_func (tree function
, tsubst_flags_t complain
)
274 tree type
= TREE_TYPE (function
);
276 /* We have to do these by hand to avoid real pointer to member
278 if (TREE_CODE (type
) == METHOD_TYPE
)
280 if (TREE_CODE (function
) == OFFSET_REF
)
282 tree object
= build_address (TREE_OPERAND (function
, 0));
283 return get_member_function_from_ptrfunc (&object
,
284 TREE_OPERAND (function
, 1),
287 function
= build_address (function
);
290 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
295 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
296 POINTER_TYPE to those. Note, pointer to member function types
297 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
298 two variants. build_call_a is the primitive taking an array of
299 arguments, while build_call_n is a wrapper that handles varargs. */
302 build_call_n (tree function
, int n
, ...)
305 return build_call_a (function
, 0, NULL
);
308 tree
*argarray
= XALLOCAVEC (tree
, n
);
313 for (i
= 0; i
< n
; i
++)
314 argarray
[i
] = va_arg (ap
, tree
);
316 return build_call_a (function
, n
, argarray
);
320 /* Update various flags in cfun and the call itself based on what is being
321 called. Split out of build_call_a so that bot_manip can use it too. */
324 set_flags_from_callee (tree call
)
326 /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */
327 tree decl
= cp_get_callee_fndecl_nofold (call
);
329 /* We check both the decl and the type; a function may be known not to
330 throw without being declared throw(). */
331 bool nothrow
= decl
&& TREE_NOTHROW (decl
);
332 tree callee
= cp_get_callee (call
);
334 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (callee
)));
335 else if (TREE_CODE (call
) == CALL_EXPR
336 && internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
339 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
340 cp_function_chain
->can_throw
= 1;
342 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
343 current_function_returns_abnormally
= 1;
345 TREE_NOTHROW (call
) = nothrow
;
349 build_call_a (tree function
, int n
, tree
*argarray
)
356 function
= build_addr_func (function
, tf_warning_or_error
);
358 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
359 fntype
= TREE_TYPE (TREE_TYPE (function
));
360 gcc_assert (FUNC_OR_METHOD_TYPE_P (fntype
));
361 result_type
= TREE_TYPE (fntype
);
362 /* An rvalue has no cv-qualifiers. */
363 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
364 result_type
= cv_unqualified (result_type
);
366 function
= build_call_array_loc (input_location
,
367 result_type
, function
, n
, argarray
);
368 set_flags_from_callee (function
);
370 decl
= get_callee_fndecl (function
);
372 if (decl
&& !TREE_USED (decl
))
374 /* We invoke build_call directly for several library
375 functions. These may have been declared normally if
376 we're building libgcc, so we can't just check
378 gcc_assert (DECL_ARTIFICIAL (decl
)
379 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
384 require_complete_eh_spec_types (fntype
, decl
);
386 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
388 /* Don't pass empty class objects by value. This is useful
389 for tags in STL, which are used to control overload resolution.
390 We don't need to handle other cases of copying empty classes. */
391 if (!decl
|| !fndecl_built_in_p (decl
))
392 for (i
= 0; i
< n
; i
++)
394 tree arg
= CALL_EXPR_ARG (function
, i
);
395 if (is_empty_class (TREE_TYPE (arg
))
396 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
398 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
399 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
400 CALL_EXPR_ARG (function
, i
) = arg
;
407 /* New overloading code. */
411 struct candidate_warning
{
413 candidate_warning
*next
;
416 /* Information for providing diagnostics about why overloading failed. */
418 enum rejection_reason_code
{
421 rr_explicit_conversion
,
422 rr_template_conversion
,
424 rr_bad_arg_conversion
,
425 rr_template_unification
,
428 rr_constraint_failure
431 struct conversion_info
{
432 /* The index of the argument, 0-based. */
434 /* The actual argument or its type. */
436 /* The type of the parameter. */
438 /* The location of the argument. */
442 struct rejection_reason
{
443 enum rejection_reason_code code
;
445 /* Information about an arity mismatch. */
447 /* The expected number of arguments. */
449 /* The actual number of arguments in the call. */
451 /* Whether the call was a varargs call. */
454 /* Information about an argument conversion mismatch. */
455 struct conversion_info conversion
;
456 /* Same, but for bad argument conversions. */
457 struct conversion_info bad_conversion
;
458 /* Information about template unification failures. These are the
459 parameters passed to fn_type_unification. */
467 unification_kind_t strict
;
469 } template_unification
;
470 /* Information about template instantiation failures. These are the
471 parameters passed to instantiate_template. */
475 } template_instantiation
;
480 /* The FUNCTION_DECL that will be called if this candidate is
481 selected by overload resolution. */
483 /* If not NULL_TREE, the first argument to use when calling this
486 /* The rest of the arguments to use when calling this function. If
487 there are no further arguments this may be NULL or it may be an
489 const vec
<tree
, va_gc
> *args
;
490 /* The implicit conversion sequences for each of the arguments to
493 /* The number of implicit conversion sequences. */
495 /* If FN is a user-defined conversion, the standard conversion
496 sequence from the type returned by FN to the desired destination
498 conversion
*second_conv
;
499 struct rejection_reason
*reason
;
500 /* If FN is a member function, the binfo indicating the path used to
501 qualify the name of FN at the call site. This path is used to
502 determine whether or not FN is accessible if it is selected by
503 overload resolution. The DECL_CONTEXT of FN will always be a
504 (possibly improper) base of this binfo. */
506 /* If FN is a non-static member function, the binfo indicating the
507 subobject to which the `this' pointer should be converted if FN
508 is selected by overload resolution. The type pointed to by
509 the `this' pointer must correspond to the most derived class
510 indicated by the CONVERSION_PATH. */
511 tree conversion_path
;
514 candidate_warning
*warnings
;
518 /* The flags active in add_candidate. */
522 /* Returns true iff T is a null pointer constant in the sense of
526 null_ptr_cst_p (tree t
)
528 tree type
= TREE_TYPE (t
);
532 A null pointer constant is an integral constant expression
533 (_expr.const_) rvalue of integer type that evaluates to zero or
534 an rvalue of type std::nullptr_t. */
535 if (NULLPTR_TYPE_P (type
))
538 if (cxx_dialect
>= cxx11
)
540 STRIP_ANY_LOCATION_WRAPPER (t
);
542 /* Core issue 903 says only literal 0 is a null pointer constant. */
543 if (TREE_CODE (t
) == INTEGER_CST
544 && !TREE_OVERFLOW (t
)
545 && TREE_CODE (type
) == INTEGER_TYPE
547 && !char_type_p (type
))
550 else if (CP_INTEGRAL_TYPE_P (type
))
552 t
= fold_non_dependent_expr (t
, tf_none
);
554 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
561 /* Returns true iff T is a null member pointer value (4.11). */
564 null_member_pointer_value_p (tree t
)
566 tree type
= TREE_TYPE (t
);
569 else if (TYPE_PTRMEMFUNC_P (type
))
570 return (TREE_CODE (t
) == CONSTRUCTOR
571 && CONSTRUCTOR_NELTS (t
)
572 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
573 else if (TYPE_PTRDATAMEM_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
,
635 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
636 int adjust
= first_arg
!= NULL_TREE
;
637 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
638 r
->u
.conversion
.from
= from
;
639 r
->u
.conversion
.to_type
= to
;
640 r
->u
.conversion
.loc
= loc
;
644 static struct rejection_reason
*
645 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
648 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
649 int adjust
= first_arg
!= NULL_TREE
;
650 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
651 r
->u
.bad_conversion
.from
= from
;
652 r
->u
.bad_conversion
.to_type
= to
;
653 r
->u
.bad_conversion
.loc
= loc
;
657 static struct rejection_reason
*
658 explicit_conversion_rejection (tree from
, tree to
)
660 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
661 r
->u
.conversion
.n_arg
= 0;
662 r
->u
.conversion
.from
= from
;
663 r
->u
.conversion
.to_type
= to
;
664 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
668 static struct rejection_reason
*
669 template_conversion_rejection (tree from
, tree to
)
671 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
672 r
->u
.conversion
.n_arg
= 0;
673 r
->u
.conversion
.from
= from
;
674 r
->u
.conversion
.to_type
= to
;
675 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
679 static struct rejection_reason
*
680 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
681 const tree
*args
, unsigned int nargs
,
682 tree return_type
, unification_kind_t strict
,
685 size_t args_n_bytes
= sizeof (*args
) * nargs
;
686 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
687 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
688 r
->u
.template_unification
.tmpl
= tmpl
;
689 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
690 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
691 /* Copy args to our own storage. */
692 memcpy (args1
, args
, args_n_bytes
);
693 r
->u
.template_unification
.args
= args1
;
694 r
->u
.template_unification
.nargs
= nargs
;
695 r
->u
.template_unification
.return_type
= return_type
;
696 r
->u
.template_unification
.strict
= strict
;
697 r
->u
.template_unification
.flags
= flags
;
701 static struct rejection_reason
*
702 template_unification_error_rejection (void)
704 return alloc_rejection (rr_template_unification
);
707 static struct rejection_reason
*
708 invalid_copy_with_fn_template_rejection (void)
710 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
714 static struct rejection_reason
*
715 inherited_ctor_rejection (void)
717 struct rejection_reason
*r
= alloc_rejection (rr_inherited_ctor
);
721 // Build a constraint failure record, saving information into the
722 // template_instantiation field of the rejection. If FN is not a template
723 // declaration, the TMPL member is the FN declaration and TARGS is empty.
725 static struct rejection_reason
*
726 constraint_failure (tree fn
)
728 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
729 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
731 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
732 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
736 r
->u
.template_instantiation
.tmpl
= fn
;
737 r
->u
.template_instantiation
.targs
= NULL_TREE
;
742 /* Dynamically allocate a conversion. */
745 alloc_conversion (conversion_kind kind
)
748 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
753 /* Make sure that all memory on the conversion obstack has been
757 validate_conversion_obstack (void)
759 if (conversion_obstack_initialized
)
760 gcc_assert ((obstack_next_free (&conversion_obstack
)
761 == obstack_base (&conversion_obstack
)));
764 /* Dynamically allocate an array of N conversions. */
767 alloc_conversions (size_t n
)
769 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
773 build_conv (conversion_kind code
, tree type
, conversion
*from
)
776 conversion_rank rank
= CONVERSION_RANK (from
);
778 /* Note that the caller is responsible for filling in t->cand for
779 user-defined conversions. */
780 t
= alloc_conversion (code
);
804 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
805 t
->bad_p
= from
->bad_p
;
810 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
811 specialization of std::initializer_list<T>, if such a conversion is
815 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
817 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
818 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
819 conversion
**subconvs
= alloc_conversions (len
);
824 /* Within a list-initialization we can have more user-defined
826 flags
&= ~LOOKUP_NO_CONVERSION
;
827 /* But no narrowing conversions. */
828 flags
|= LOOKUP_NO_NARROWING
;
830 /* Can't make an array of these types. */
831 if (TYPE_REF_P (elttype
)
832 || TREE_CODE (elttype
) == FUNCTION_TYPE
833 || VOID_TYPE_P (elttype
))
836 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
839 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
840 false, flags
, complain
);
847 t
= alloc_conversion (ck_list
);
849 t
->u
.list
= subconvs
;
852 for (i
= 0; i
< len
; ++i
)
854 conversion
*sub
= subconvs
[i
];
855 if (sub
->rank
> t
->rank
)
857 if (sub
->user_conv_p
)
858 t
->user_conv_p
= true;
866 /* Return the next conversion of the conversion chain (if applicable),
867 or NULL otherwise. Please use this function instead of directly
868 accessing fields of struct conversion. */
871 next_conversion (conversion
*conv
)
874 || conv
->kind
== ck_identity
875 || conv
->kind
== ck_ambig
876 || conv
->kind
== ck_list
)
881 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
882 is a valid aggregate initializer for array type ATYPE. */
885 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
888 tree elttype
= TREE_TYPE (atype
);
889 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
891 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
893 if (TREE_CODE (elttype
) == ARRAY_TYPE
894 && TREE_CODE (val
) == CONSTRUCTOR
)
895 ok
= can_convert_array (elttype
, val
, flags
, complain
);
897 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
905 /* Helper for build_aggr_conv. Return true if FIELD is in PSET, or if
906 FIELD has ANON_AGGR_TYPE_P and any initializable field in there recursively
910 field_in_pset (hash_set
<tree
, true> &pset
, tree field
)
912 if (pset
.contains (field
))
914 if (ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
915 for (field
= TYPE_FIELDS (TREE_TYPE (field
));
916 field
; field
= DECL_CHAIN (field
))
918 field
= next_initializable_field (field
);
919 if (field
== NULL_TREE
)
921 if (field_in_pset (pset
, field
))
927 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
928 aggregate class, if such a conversion is possible. */
931 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
933 unsigned HOST_WIDE_INT i
= 0;
935 tree field
= next_initializable_field (TYPE_FIELDS (type
));
936 tree empty_ctor
= NULL_TREE
;
937 hash_set
<tree
, true> pset
;
939 /* We already called reshape_init in implicit_conversion. */
941 /* The conversions within the init-list aren't affected by the enclosing
942 context; they're always simple copy-initialization. */
943 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
945 /* For designated initializers, verify that each initializer is convertible
946 to corresponding TREE_TYPE (ce->index) and mark those FIELD_DECLs as
947 visited. In the following loop then ignore already visited
949 if (CONSTRUCTOR_IS_DESIGNATED_INIT (ctor
))
952 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor
), i
, idx
, val
)
954 if (idx
&& TREE_CODE (idx
) == FIELD_DECL
)
956 tree ftype
= TREE_TYPE (idx
);
959 if (TREE_CODE (ftype
) == ARRAY_TYPE
960 && TREE_CODE (val
) == CONSTRUCTOR
)
961 ok
= can_convert_array (ftype
, val
, flags
, complain
);
963 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
968 /* For unions, there should be just one initializer. */
969 if (TREE_CODE (type
) == UNION_TYPE
)
982 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
984 tree ftype
= TREE_TYPE (field
);
988 if (!pset
.is_empty () && field_in_pset (pset
, field
))
990 if (i
< CONSTRUCTOR_NELTS (ctor
))
992 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
995 else if (DECL_INITIAL (field
))
996 val
= get_nsdmi (field
, /*ctor*/false, complain
);
997 else if (TYPE_REF_P (ftype
))
998 /* Value-initialization of reference is ill-formed. */
1002 if (empty_ctor
== NULL_TREE
)
1003 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
1007 if (TREE_CODE (ftype
) == ARRAY_TYPE
1008 && TREE_CODE (val
) == CONSTRUCTOR
)
1009 ok
= can_convert_array (ftype
, val
, flags
, complain
);
1011 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
1017 if (TREE_CODE (type
) == UNION_TYPE
)
1021 if (i
< CONSTRUCTOR_NELTS (ctor
))
1024 c
= alloc_conversion (ck_aggr
);
1027 c
->user_conv_p
= true;
1028 c
->check_narrowing
= true;
1033 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
1034 array type, if such a conversion is possible. */
1037 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
1040 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1041 tree elttype
= TREE_TYPE (type
);
1046 enum conversion_rank rank
= cr_exact
;
1048 /* We might need to propagate the size from the element to the array. */
1049 complete_type (type
);
1051 if (TYPE_DOMAIN (type
)
1052 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
1054 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
1059 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1061 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1064 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1065 false, flags
, complain
);
1069 if (sub
->rank
> rank
)
1071 if (sub
->user_conv_p
)
1077 c
= alloc_conversion (ck_aggr
);
1080 c
->user_conv_p
= user
;
1086 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1087 complex type, if such a conversion is possible. */
1090 build_complex_conv (tree type
, tree ctor
, int flags
,
1091 tsubst_flags_t complain
)
1094 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1095 tree elttype
= TREE_TYPE (type
);
1100 enum conversion_rank rank
= cr_exact
;
1105 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1107 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1110 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1111 false, flags
, complain
);
1115 if (sub
->rank
> rank
)
1117 if (sub
->user_conv_p
)
1123 c
= alloc_conversion (ck_aggr
);
1126 c
->user_conv_p
= user
;
1132 /* Build a representation of the identity conversion from EXPR to
1133 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1136 build_identity_conv (tree type
, tree expr
)
1140 c
= alloc_conversion (ck_identity
);
1147 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1148 were multiple user-defined conversions to accomplish the job.
1149 Build a conversion that indicates that ambiguity. */
1152 build_ambiguous_conv (tree type
, tree expr
)
1156 c
= alloc_conversion (ck_ambig
);
1164 strip_top_quals (tree t
)
1166 if (TREE_CODE (t
) == ARRAY_TYPE
)
1168 return cp_build_qualified_type (t
, 0);
1171 /* Returns the standard conversion path (see [conv]) from type FROM to type
1172 TO, if any. For proper handling of null pointer constants, you must
1173 also pass the expression EXPR to convert from. If C_CAST_P is true,
1174 this conversion is coming from a C-style cast. */
1177 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1178 int flags
, tsubst_flags_t complain
)
1180 enum tree_code fcode
, tcode
;
1182 bool fromref
= false;
1185 to
= non_reference (to
);
1186 if (TYPE_REF_P (from
))
1189 from
= TREE_TYPE (from
);
1192 to
= strip_top_quals (to
);
1193 from
= strip_top_quals (from
);
1195 if (expr
&& type_unknown_p (expr
))
1197 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1199 tsubst_flags_t tflags
= tf_conv
;
1200 expr
= instantiate_type (to
, expr
, tflags
);
1201 if (expr
== error_mark_node
)
1203 from
= TREE_TYPE (expr
);
1205 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1207 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1208 expr
= resolve_nondeduced_context (expr
, complain
);
1209 from
= TREE_TYPE (expr
);
1213 fcode
= TREE_CODE (from
);
1214 tcode
= TREE_CODE (to
);
1216 conv
= build_identity_conv (from
, expr
);
1217 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1219 from
= type_decays_to (from
);
1220 fcode
= TREE_CODE (from
);
1221 /* Tell convert_like_real that we're using the address. */
1222 conv
->rvaluedness_matches_p
= true;
1223 conv
= build_conv (ck_lvalue
, from
, conv
);
1225 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1226 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1227 express the copy constructor call required by copy-initialization. */
1228 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1233 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1236 from
= strip_top_quals (bitfield_type
);
1237 fcode
= TREE_CODE (from
);
1240 conv
= build_conv (ck_rvalue
, from
, conv
);
1241 if (flags
& LOOKUP_PREFER_RVALUE
)
1242 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1243 conv
->rvaluedness_matches_p
= true;
1246 /* Allow conversion between `__complex__' data types. */
1247 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1249 /* The standard conversion sequence to convert FROM to TO is
1250 the standard conversion sequence to perform componentwise
1252 conversion
*part_conv
= standard_conversion
1253 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1258 conv
= build_conv (part_conv
->kind
, to
, conv
);
1259 conv
->rank
= part_conv
->rank
;
1267 if (same_type_p (from
, to
))
1269 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1270 conv
->type
= qualified_to
;
1275 A null pointer constant can be converted to a pointer type; ... A
1276 null pointer constant of integral type can be converted to an
1277 rvalue of type std::nullptr_t. */
1278 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1279 || NULLPTR_TYPE_P (to
))
1280 && ((expr
&& null_ptr_cst_p (expr
))
1281 || NULLPTR_TYPE_P (from
)))
1282 conv
= build_conv (ck_std
, to
, conv
);
1283 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1284 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1286 /* For backwards brain damage compatibility, allow interconversion of
1287 pointers and integers with a pedwarn. */
1288 conv
= build_conv (ck_std
, to
, conv
);
1291 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1293 /* For backwards brain damage compatibility, allow interconversion of
1294 enums and integers with a pedwarn. */
1295 conv
= build_conv (ck_std
, to
, conv
);
1298 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1299 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1304 if (tcode
== POINTER_TYPE
)
1306 to_pointee
= TREE_TYPE (to
);
1307 from_pointee
= TREE_TYPE (from
);
1309 /* Since this is the target of a pointer, it can't have function
1310 qualifiers, so any TYPE_QUALS must be for attributes const or
1311 noreturn. Strip them. */
1312 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1313 && TYPE_QUALS (to_pointee
))
1314 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1315 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1316 && TYPE_QUALS (from_pointee
))
1317 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1321 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1322 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1325 if (tcode
== POINTER_TYPE
1326 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1329 else if (VOID_TYPE_P (to_pointee
)
1330 && !TYPE_PTRDATAMEM_P (from
)
1331 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1333 tree nfrom
= TREE_TYPE (from
);
1334 /* Don't try to apply restrict to void. */
1335 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1336 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1337 from
= build_pointer_type (from_pointee
);
1338 conv
= build_conv (ck_ptr
, from
, conv
);
1340 else if (TYPE_PTRDATAMEM_P (from
))
1342 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1343 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1345 if (same_type_p (fbase
, tbase
))
1346 /* No base conversion needed. */;
1347 else if (DERIVED_FROM_P (fbase
, tbase
)
1348 && (same_type_ignoring_top_level_qualifiers_p
1349 (from_pointee
, to_pointee
)))
1351 from
= build_ptrmem_type (tbase
, from_pointee
);
1352 conv
= build_conv (ck_pmem
, from
, conv
);
1357 else if (CLASS_TYPE_P (from_pointee
)
1358 && CLASS_TYPE_P (to_pointee
)
1361 An rvalue of type "pointer to cv D," where D is a
1362 class type, can be converted to an rvalue of type
1363 "pointer to cv B," where B is a base class (clause
1364 _class.derived_) of D. If B is an inaccessible
1365 (clause _class.access_) or ambiguous
1366 (_class.member.lookup_) base class of D, a program
1367 that necessitates this conversion is ill-formed.
1368 Therefore, we use DERIVED_FROM_P, and do not check
1369 access or uniqueness. */
1370 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1373 = cp_build_qualified_type (to_pointee
,
1374 cp_type_quals (from_pointee
));
1375 from
= build_pointer_type (from_pointee
);
1376 conv
= build_conv (ck_ptr
, from
, conv
);
1377 conv
->base_p
= true;
1380 if (same_type_p (from
, to
))
1382 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1383 /* In a C-style cast, we ignore CV-qualification because we
1384 are allowed to perform a static_cast followed by a
1386 conv
= build_conv (ck_qual
, to
, conv
);
1387 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1388 conv
= build_conv (ck_qual
, to
, conv
);
1389 else if (expr
&& string_conv_p (to
, expr
, 0))
1390 /* converting from string constant to char *. */
1391 conv
= build_conv (ck_qual
, to
, conv
);
1392 else if (fnptr_conv_p (to
, from
))
1393 conv
= build_conv (ck_fnptr
, to
, conv
);
1394 /* Allow conversions among compatible ObjC pointer types (base
1395 conversions have been already handled above). */
1396 else if (c_dialect_objc ()
1397 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1398 conv
= build_conv (ck_ptr
, to
, conv
);
1399 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1401 conv
= build_conv (ck_ptr
, to
, conv
);
1409 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1411 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1412 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1413 tree fbase
= class_of_this_parm (fromfn
);
1414 tree tbase
= class_of_this_parm (tofn
);
1416 if (!DERIVED_FROM_P (fbase
, tbase
))
1419 tree fstat
= static_fn_type (fromfn
);
1420 tree tstat
= static_fn_type (tofn
);
1421 if (same_type_p (tstat
, fstat
)
1422 || fnptr_conv_p (tstat
, fstat
))
1427 if (!same_type_p (fbase
, tbase
))
1429 from
= build_memfn_type (fstat
,
1431 cp_type_quals (tbase
),
1432 type_memfn_rqual (tofn
));
1433 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1434 conv
= build_conv (ck_pmem
, from
, conv
);
1435 conv
->base_p
= true;
1437 if (fnptr_conv_p (tstat
, fstat
))
1438 conv
= build_conv (ck_fnptr
, to
, conv
);
1440 else if (tcode
== BOOLEAN_TYPE
)
1444 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1445 to member type can be converted to a prvalue of type bool. ...
1446 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1447 std::nullptr_t can be converted to a prvalue of type bool; */
1448 if (ARITHMETIC_TYPE_P (from
)
1449 || UNSCOPED_ENUM_P (from
)
1450 || fcode
== POINTER_TYPE
1451 || TYPE_PTRMEM_P (from
)
1452 || NULLPTR_TYPE_P (from
))
1454 conv
= build_conv (ck_std
, to
, conv
);
1455 if (fcode
== POINTER_TYPE
1456 || TYPE_PTRDATAMEM_P (from
)
1457 || (TYPE_PTRMEMFUNC_P (from
)
1458 && conv
->rank
< cr_pbool
)
1459 || NULLPTR_TYPE_P (from
))
1460 conv
->rank
= cr_pbool
;
1461 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1463 if (flags
& LOOKUP_NO_NARROWING
)
1464 conv
->check_narrowing
= true;
1470 /* We don't check for ENUMERAL_TYPE here because there are no standard
1471 conversions to enum type. */
1472 /* As an extension, allow conversion to complex type. */
1473 else if (ARITHMETIC_TYPE_P (to
))
1475 if (! (INTEGRAL_CODE_P (fcode
)
1476 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1477 || SCOPED_ENUM_P (from
))
1480 /* If we're parsing an enum with no fixed underlying type, we're
1481 dealing with an incomplete type, which renders the conversion
1483 if (!COMPLETE_TYPE_P (from
))
1486 conv
= build_conv (ck_std
, to
, conv
);
1488 /* Give this a better rank if it's a promotion. */
1489 if (same_type_p (to
, type_promotes_to (from
))
1490 && next_conversion (conv
)->rank
<= cr_promotion
)
1491 conv
->rank
= cr_promotion
;
1493 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1494 && vector_types_convertible_p (from
, to
, false))
1495 return build_conv (ck_std
, to
, conv
);
1496 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1497 && is_properly_derived_from (from
, to
))
1499 if (conv
->kind
== ck_rvalue
)
1500 conv
= next_conversion (conv
);
1501 conv
= build_conv (ck_base
, to
, conv
);
1502 /* The derived-to-base conversion indicates the initialization
1503 of a parameter with base type from an object of a derived
1504 type. A temporary object is created to hold the result of
1505 the conversion unless we're binding directly to a reference. */
1506 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1507 if (flags
& LOOKUP_PREFER_RVALUE
)
1508 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1509 conv
->rvaluedness_matches_p
= true;
1514 if (flags
& LOOKUP_NO_NARROWING
)
1515 conv
->check_narrowing
= true;
1520 /* Returns nonzero if T1 is reference-related to T2. */
1523 reference_related_p (tree t1
, tree t2
)
1525 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1528 t1
= TYPE_MAIN_VARIANT (t1
);
1529 t2
= TYPE_MAIN_VARIANT (t2
);
1533 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1534 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1536 return (same_type_p (t1
, t2
)
1537 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1538 && DERIVED_FROM_P (t1
, t2
)));
1541 /* Returns nonzero if T1 is reference-compatible with T2. */
1544 reference_compatible_p (tree t1
, tree t2
)
1548 "cv1 T1" is reference compatible with "cv2 T2" if
1549 * T1 is reference-related to T2 or
1550 * T2 is "noexcept function" and T1 is "function", where the
1551 function types are otherwise the same,
1552 and cv1 is the same cv-qualification as, or greater cv-qualification
1554 return ((reference_related_p (t1
, t2
)
1555 || fnptr_conv_p (t1
, t2
))
1556 && at_least_as_qualified_p (t1
, t2
));
1559 /* A reference of the indicated TYPE is being bound directly to the
1560 expression represented by the implicit conversion sequence CONV.
1561 Return a conversion sequence for this binding. */
1564 direct_reference_binding (tree type
, conversion
*conv
)
1568 gcc_assert (TYPE_REF_P (type
));
1569 gcc_assert (!TYPE_REF_P (conv
->type
));
1571 t
= TREE_TYPE (type
);
1573 if (conv
->kind
== ck_identity
)
1574 /* Mark the identity conv as to not decay to rvalue. */
1575 conv
->rvaluedness_matches_p
= true;
1579 When a parameter of reference type binds directly
1580 (_dcl.init.ref_) to an argument expression, the implicit
1581 conversion sequence is the identity conversion, unless the
1582 argument expression has a type that is a derived class of the
1583 parameter type, in which case the implicit conversion sequence is
1584 a derived-to-base Conversion.
1586 If the parameter binds directly to the result of applying a
1587 conversion function to the argument expression, the implicit
1588 conversion sequence is a user-defined conversion sequence
1589 (_over.ics.user_), with the second standard conversion sequence
1590 either an identity conversion or, if the conversion function
1591 returns an entity of a type that is a derived class of the
1592 parameter type, a derived-to-base conversion. */
1593 if (is_properly_derived_from (conv
->type
, t
))
1595 /* Represent the derived-to-base conversion. */
1596 conv
= build_conv (ck_base
, t
, conv
);
1597 /* We will actually be binding to the base-class subobject in
1598 the derived class, so we mark this conversion appropriately.
1599 That way, convert_like knows not to generate a temporary. */
1600 conv
->need_temporary_p
= false;
1603 return build_conv (ck_ref_bind
, type
, conv
);
1606 /* Returns the conversion path from type FROM to reference type TO for
1607 purposes of reference binding. For lvalue binding, either pass a
1608 reference type to FROM or an lvalue expression to EXPR. If the
1609 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1610 the conversion returned. If C_CAST_P is true, this
1611 conversion is coming from a C-style cast. */
1614 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1615 tsubst_flags_t complain
)
1617 conversion
*conv
= NULL
;
1618 tree to
= TREE_TYPE (rto
);
1623 cp_lvalue_kind gl_kind
;
1626 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1628 expr
= instantiate_type (to
, expr
, tf_none
);
1629 if (expr
== error_mark_node
)
1631 from
= TREE_TYPE (expr
);
1634 bool copy_list_init
= false;
1635 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1637 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1638 /* DR 1288: Otherwise, if the initializer list has a single element
1639 of type E and ... [T's] referenced type is reference-related to E,
1640 the object or reference is initialized from that element... */
1641 if (CONSTRUCTOR_NELTS (expr
) == 1)
1643 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1644 if (error_operand_p (elt
))
1646 tree etype
= TREE_TYPE (elt
);
1647 if (reference_related_p (to
, etype
))
1654 /* Otherwise, if T is a reference type, a prvalue temporary of the type
1655 referenced by T is copy-list-initialized, and the reference is bound
1656 to that temporary. */
1657 copy_list_init
= true;
1661 if (TYPE_REF_P (from
))
1663 from
= TREE_TYPE (from
);
1664 if (!TYPE_REF_IS_RVALUE (rfrom
)
1665 || TREE_CODE (from
) == FUNCTION_TYPE
)
1666 gl_kind
= clk_ordinary
;
1668 gl_kind
= clk_rvalueref
;
1671 gl_kind
= lvalue_kind (expr
);
1672 else if (CLASS_TYPE_P (from
)
1673 || TREE_CODE (from
) == ARRAY_TYPE
)
1674 gl_kind
= clk_class
;
1678 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1679 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1680 && (gl_kind
& clk_class
))
1683 /* Same mask as real_lvalue_p. */
1684 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1687 if ((gl_kind
& clk_bitfield
) != 0)
1688 tfrom
= unlowered_expr_type (expr
);
1690 /* Figure out whether or not the types are reference-related and
1691 reference compatible. We have to do this after stripping
1692 references from FROM. */
1693 related_p
= reference_related_p (to
, tfrom
);
1694 /* If this is a C cast, first convert to an appropriately qualified
1695 type, so that we can later do a const_cast to the desired type. */
1696 if (related_p
&& c_cast_p
1697 && !at_least_as_qualified_p (to
, tfrom
))
1698 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1699 compatible_p
= reference_compatible_p (to
, tfrom
);
1701 /* Directly bind reference when target expression's type is compatible with
1702 the reference and expression is an lvalue. In DR391, the wording in
1703 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1704 const and rvalue references to rvalues of compatible class type.
1705 We should also do direct bindings for non-class xvalues. */
1706 if ((related_p
|| compatible_p
) && gl_kind
)
1710 If the initializer expression
1712 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1713 is reference-compatible with "cv2 T2,"
1715 the reference is bound directly to the initializer expression
1719 If the initializer expression is an rvalue, with T2 a class type,
1720 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1721 is bound to the object represented by the rvalue or to a sub-object
1722 within that object. */
1724 conv
= build_identity_conv (tfrom
, expr
);
1725 conv
= direct_reference_binding (rto
, conv
);
1727 if (TYPE_REF_P (rfrom
))
1728 /* Handle rvalue reference to function properly. */
1729 conv
->rvaluedness_matches_p
1730 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1732 conv
->rvaluedness_matches_p
1733 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1735 if ((gl_kind
& clk_bitfield
) != 0
1736 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1737 /* For the purposes of overload resolution, we ignore the fact
1738 this expression is a bitfield or packed field. (In particular,
1739 [over.ics.ref] says specifically that a function with a
1740 non-const reference parameter is viable even if the
1741 argument is a bitfield.)
1743 However, when we actually call the function we must create
1744 a temporary to which to bind the reference. If the
1745 reference is volatile, or isn't const, then we cannot make
1746 a temporary, so we just issue an error when the conversion
1748 conv
->need_temporary_p
= true;
1750 /* Don't allow binding of lvalues (other than function lvalues) to
1751 rvalue references. */
1752 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1753 && TREE_CODE (to
) != FUNCTION_TYPE
)
1756 /* Nor the reverse. */
1757 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1758 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1759 || (flags
& LOOKUP_NO_RVAL_BIND
))
1760 && TREE_CODE (to
) != FUNCTION_TYPE
)
1768 /* [class.conv.fct] A conversion function is never used to convert a
1769 (possibly cv-qualified) object to the (possibly cv-qualified) same
1770 object type (or a reference to it), to a (possibly cv-qualified) base
1771 class of that type (or a reference to it).... */
1772 else if (CLASS_TYPE_P (from
) && !related_p
1773 && !(flags
& LOOKUP_NO_CONVERSION
))
1777 If the initializer expression
1779 -- has a class type (i.e., T2 is a class type) can be
1780 implicitly converted to an lvalue of type "cv3 T3," where
1781 "cv1 T1" is reference-compatible with "cv3 T3". (this
1782 conversion is selected by enumerating the applicable
1783 conversion functions (_over.match.ref_) and choosing the
1784 best one through overload resolution. (_over.match_).
1786 the reference is bound to the lvalue result of the conversion
1787 in the second case. */
1788 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1791 return cand
->second_conv
;
1794 /* From this point on, we conceptually need temporaries, even if we
1795 elide them. Only the cases above are "direct bindings". */
1796 if (flags
& LOOKUP_NO_TEMP_BIND
)
1801 When a parameter of reference type is not bound directly to an
1802 argument expression, the conversion sequence is the one required
1803 to convert the argument expression to the underlying type of the
1804 reference according to _over.best.ics_. Conceptually, this
1805 conversion sequence corresponds to copy-initializing a temporary
1806 of the underlying type with the argument expression. Any
1807 difference in top-level cv-qualification is subsumed by the
1808 initialization itself and does not constitute a conversion. */
1812 Otherwise, the reference shall be an lvalue reference to a
1813 non-volatile const type, or the reference shall be an rvalue
1816 We try below to treat this as a bad conversion to improve diagnostics,
1817 but if TO is an incomplete class, we need to reject this conversion
1818 now to avoid unnecessary instantiation. */
1819 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1820 && !COMPLETE_TYPE_P (to
))
1823 /* We're generating a temporary now, but don't bind any more in the
1824 conversion (specifically, don't slice the temporary returned by a
1825 conversion operator). */
1826 flags
|= LOOKUP_NO_TEMP_BIND
;
1828 /* Core issue 899: When [copy-]initializing a temporary to be bound
1829 to the first parameter of a copy constructor (12.8) called with
1830 a single argument in the context of direct-initialization,
1831 explicit conversion functions are also considered.
1833 So don't set LOOKUP_ONLYCONVERTING in that case. */
1834 if (!(flags
& LOOKUP_COPY_PARM
))
1835 flags
|= LOOKUP_ONLYCONVERTING
;
1838 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1843 if (conv
->user_conv_p
)
1846 /* Remember this was copy-list-initialization. */
1847 conv
->need_temporary_p
= true;
1849 /* If initializing the temporary used a conversion function,
1850 recalculate the second conversion sequence. */
1851 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1852 if (t
->kind
== ck_user
1853 && DECL_CONV_FN_P (t
->cand
->fn
))
1855 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1856 /* A prvalue of non-class type is cv-unqualified. */
1857 if (!TYPE_REF_P (ftype
) && !CLASS_TYPE_P (ftype
))
1858 ftype
= cv_unqualified (ftype
);
1859 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1860 conversion
*new_second
1861 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1865 return merge_conversion_sequences (t
, new_second
);
1869 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1870 /* This reference binding, unlike those above, requires the
1871 creation of a temporary. */
1872 conv
->need_temporary_p
= true;
1873 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1877 Otherwise, the reference shall be an lvalue reference to a
1878 non-volatile const type, or the reference shall be an rvalue
1880 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1885 Otherwise, a temporary of type "cv1 T1" is created and
1886 initialized from the initializer expression using the rules for a
1887 non-reference copy initialization. If T1 is reference-related to
1888 T2, cv1 must be the same cv-qualification as, or greater
1889 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1890 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1896 /* Returns the implicit conversion sequence (see [over.ics]) from type
1897 FROM to type TO. The optional expression EXPR may affect the
1898 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1899 true, this conversion is coming from a C-style cast. */
1902 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1903 int flags
, tsubst_flags_t complain
)
1907 if (from
== error_mark_node
|| to
== error_mark_node
1908 || expr
== error_mark_node
)
1911 /* Other flags only apply to the primary function in overload
1912 resolution, or after we've chosen one. */
1913 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1914 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1915 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1917 /* FIXME: actually we don't want warnings either, but we can't just
1918 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1919 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1920 We really ought not to issue that warning until we've committed
1921 to that conversion. */
1922 complain
&= ~tf_error
;
1924 /* Call reshape_init early to remove redundant braces. */
1925 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1926 && CLASS_TYPE_P (to
)
1927 && COMPLETE_TYPE_P (complete_type (to
))
1928 && !CLASSTYPE_NON_AGGREGATE (to
))
1930 expr
= reshape_init (to
, expr
, complain
);
1931 if (expr
== error_mark_node
)
1933 from
= TREE_TYPE (expr
);
1936 if (TYPE_REF_P (to
))
1937 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1939 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1944 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1946 if (is_std_init_list (to
) && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1947 return build_list_conv (to
, expr
, flags
, complain
);
1949 /* As an extension, allow list-initialization of _Complex. */
1950 if (TREE_CODE (to
) == COMPLEX_TYPE
1951 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1953 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1958 /* Allow conversion from an initializer-list with one element to a
1960 if (SCALAR_TYPE_P (to
))
1962 int nelts
= CONSTRUCTOR_NELTS (expr
);
1966 elt
= build_value_init (to
, tf_none
);
1967 else if (nelts
== 1 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1968 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1970 elt
= error_mark_node
;
1972 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1973 c_cast_p
, flags
, complain
);
1976 conv
->check_narrowing
= true;
1977 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1978 /* Too many levels of braces, i.e. '{{1}}'. */
1983 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1984 return build_array_conv (to
, expr
, flags
, complain
);
1987 if (expr
!= NULL_TREE
1988 && (MAYBE_CLASS_TYPE_P (from
)
1989 || MAYBE_CLASS_TYPE_P (to
))
1990 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1992 struct z_candidate
*cand
;
1994 if (CLASS_TYPE_P (to
)
1995 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1996 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1997 return build_aggr_conv (to
, expr
, flags
, complain
);
1999 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
2002 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
2003 && CONSTRUCTOR_NELTS (expr
) == 1
2004 && !is_list_ctor (cand
->fn
))
2006 /* "If C is not an initializer-list constructor and the
2007 initializer list has a single element of type cv U, where U is
2008 X or a class derived from X, the implicit conversion sequence
2009 has Exact Match rank if U is X, or Conversion rank if U is
2011 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
2012 tree elttype
= TREE_TYPE (elt
);
2013 if (reference_related_p (to
, elttype
))
2014 return implicit_conversion (to
, elttype
, elt
,
2015 c_cast_p
, flags
, complain
);
2017 conv
= cand
->second_conv
;
2020 /* We used to try to bind a reference to a temporary here, but that
2021 is now handled after the recursive call to this function at the end
2022 of reference_binding. */
2029 /* Like implicit_conversion, but return NULL if the conversion is bad.
2031 This is not static so that check_non_deducible_conversion can call it within
2032 add_template_candidate_real as part of overload resolution; it should not be
2033 called outside of overload resolution. */
2036 good_conversion (tree to
, tree from
, tree expr
,
2037 int flags
, tsubst_flags_t complain
)
2039 conversion
*c
= implicit_conversion (to
, from
, expr
, /*cast*/false,
2046 /* Add a new entry to the list of candidates. Used by the add_*_candidate
2047 functions. ARGS will not be changed until a single candidate is
2050 static struct z_candidate
*
2051 add_candidate (struct z_candidate
**candidates
,
2052 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
2053 size_t num_convs
, conversion
**convs
,
2054 tree access_path
, tree conversion_path
,
2055 int viable
, struct rejection_reason
*reason
,
2058 struct z_candidate
*cand
= (struct z_candidate
*)
2059 conversion_obstack_alloc (sizeof (struct z_candidate
));
2062 cand
->first_arg
= first_arg
;
2064 cand
->convs
= convs
;
2065 cand
->num_convs
= num_convs
;
2066 cand
->access_path
= access_path
;
2067 cand
->conversion_path
= conversion_path
;
2068 cand
->viable
= viable
;
2069 cand
->reason
= reason
;
2070 cand
->next
= *candidates
;
2071 cand
->flags
= flags
;
2077 /* Return the number of remaining arguments in the parameter list
2078 beginning with ARG. */
2081 remaining_arguments (tree arg
)
2085 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
2086 arg
= TREE_CHAIN (arg
))
2092 /* [over.match.copy]: When initializing a temporary object (12.2) to be bound
2093 to the first parameter of a constructor where the parameter is of type
2094 "reference to possibly cv-qualified T" and the constructor is called with a
2095 single argument in the context of direct-initialization of an object of type
2096 "cv2 T", explicit conversion functions are also considered.
2098 So set LOOKUP_COPY_PARM to let reference_binding know that
2099 it's being called in that context. */
2102 conv_flags (int i
, int nargs
, tree fn
, tree arg
, int flags
)
2106 if (i
== 0 && nargs
== 1 && DECL_CONSTRUCTOR_P (fn
)
2107 && (t
= FUNCTION_FIRST_USER_PARMTYPE (fn
))
2108 && (same_type_ignoring_top_level_qualifiers_p
2109 (non_reference (TREE_VALUE (t
)), DECL_CONTEXT (fn
))))
2111 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2112 lflags
|= LOOKUP_COPY_PARM
;
2113 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2114 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2115 lflags
|= LOOKUP_NO_CONVERSION
;
2118 lflags
|= LOOKUP_ONLYCONVERTING
;
2123 /* Create an overload candidate for the function or method FN called
2124 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
2125 FLAGS is passed on to implicit_conversion.
2127 This does not change ARGS.
2129 CTYPE, if non-NULL, is the type we want to pretend this function
2130 comes from for purposes of overload resolution. */
2132 static struct z_candidate
*
2133 add_function_candidate (struct z_candidate
**candidates
,
2134 tree fn
, tree ctype
, tree first_arg
,
2135 const vec
<tree
, va_gc
> *args
, tree access_path
,
2136 tree conversion_path
, int flags
,
2138 tsubst_flags_t complain
)
2140 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2143 tree orig_first_arg
= first_arg
;
2146 struct rejection_reason
*reason
= NULL
;
2148 /* At this point we should not see any functions which haven't been
2149 explicitly declared, except for friend functions which will have
2150 been found using argument dependent lookup. */
2151 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2153 /* The `this', `in_chrg' and VTT arguments to constructors are not
2154 considered in overload resolution. */
2155 if (DECL_CONSTRUCTOR_P (fn
))
2157 if (ctor_omit_inherited_parms (fn
))
2158 /* Bring back parameters omitted from an inherited ctor. */
2159 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2161 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2162 skip
= num_artificial_parms_for (fn
);
2163 if (skip
> 0 && first_arg
!= NULL_TREE
)
2166 first_arg
= NULL_TREE
;
2172 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2174 convs
= alloc_conversions (len
);
2176 /* 13.3.2 - Viable functions [over.match.viable]
2177 First, to be a viable function, a candidate function shall have enough
2178 parameters to agree in number with the arguments in the list.
2180 We need to check this first; otherwise, checking the ICSes might cause
2181 us to produce an ill-formed template instantiation. */
2183 parmnode
= parmlist
;
2184 for (i
= 0; i
< len
; ++i
)
2186 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2188 parmnode
= TREE_CHAIN (parmnode
);
2191 if ((i
< len
&& parmnode
)
2192 || !sufficient_parms_p (parmnode
))
2194 int remaining
= remaining_arguments (parmnode
);
2196 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2199 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2200 parameter of type "reference to cv C" (including such a constructor
2201 instantiated from a template) is excluded from the set of candidate
2202 functions when used to construct an object of type D with an argument list
2203 containing a single argument if C is reference-related to D. */
2204 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2205 && flag_new_inheriting_ctors
2206 && DECL_INHERITED_CTOR (fn
))
2208 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2209 tree dtype
= DECL_CONTEXT (fn
);
2210 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2211 if (reference_related_p (ptype
, dtype
)
2212 && reference_related_p (btype
, ptype
))
2215 reason
= inherited_ctor_rejection ();
2219 /* Second, for a function to be viable, its constraints must be
2221 if (flag_concepts
&& viable
2222 && !constraints_satisfied_p (fn
))
2224 reason
= constraint_failure (fn
);
2228 /* When looking for a function from a subobject from an implicit
2229 copy/move constructor/operator=, don't consider anything that takes (a
2230 reference to) an unrelated type. See c++/44909 and core 1092. */
2231 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2233 if (DECL_CONSTRUCTOR_P (fn
))
2235 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2236 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2242 parmnode
= chain_index (i
-1, parmlist
);
2243 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2248 /* This only applies at the top level. */
2249 flags
&= ~LOOKUP_DEFAULTED
;
2255 /* Third, for F to be a viable function, there shall exist for each
2256 argument an implicit conversion sequence that converts that argument
2257 to the corresponding parameter of F. */
2259 parmnode
= parmlist
;
2261 for (i
= 0; i
< len
; ++i
)
2263 tree argtype
, to_type
;
2268 if (parmnode
== void_list_node
)
2273 /* Already set during deduction. */
2274 parmnode
= TREE_CHAIN (parmnode
);
2278 if (i
== 0 && first_arg
!= NULL_TREE
)
2281 arg
= CONST_CAST_TREE (
2282 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2283 argtype
= lvalue_type (arg
);
2285 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2286 && ! DECL_CONSTRUCTOR_P (fn
));
2290 tree parmtype
= TREE_VALUE (parmnode
);
2292 parmnode
= TREE_CHAIN (parmnode
);
2294 /* The type of the implicit object parameter ('this') for
2295 overload resolution is not always the same as for the
2296 function itself; conversion functions are considered to
2297 be members of the class being converted, and functions
2298 introduced by a using-declaration are considered to be
2299 members of the class that uses them.
2301 Since build_over_call ignores the ICS for the `this'
2302 parameter, we can just change the parm type. */
2303 if (ctype
&& is_this
)
2305 parmtype
= cp_build_qualified_type
2306 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2307 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2309 /* If the function has a ref-qualifier, the implicit
2310 object parameter has reference type. */
2311 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2312 parmtype
= cp_build_reference_type (parmtype
, rv
);
2313 /* The special handling of 'this' conversions in compare_ics
2314 does not apply if there is a ref-qualifier. */
2319 parmtype
= build_pointer_type (parmtype
);
2320 /* We don't use build_this here because we don't want to
2321 capture the object argument until we've chosen a
2322 non-static member function. */
2323 arg
= build_address (arg
);
2324 argtype
= lvalue_type (arg
);
2328 int lflags
= conv_flags (i
, len
-skip
, fn
, arg
, flags
);
2330 t
= implicit_conversion (parmtype
, argtype
, arg
,
2331 /*c_cast_p=*/false, lflags
, complain
);
2336 t
= build_identity_conv (argtype
, arg
);
2337 t
->ellipsis_p
= true;
2348 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
,
2349 EXPR_LOCATION (arg
));
2356 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
,
2357 EXPR_LOCATION (arg
));
2363 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2364 access_path
, conversion_path
, viable
, reason
, flags
);
2367 /* Create an overload candidate for the conversion function FN which will
2368 be invoked for expression OBJ, producing a pointer-to-function which
2369 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2370 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2371 passed on to implicit_conversion.
2373 Actually, we don't really care about FN; we care about the type it
2374 converts to. There may be multiple conversion functions that will
2375 convert to that type, and we rely on build_user_type_conversion_1 to
2376 choose the best one; so when we create our candidate, we record the type
2377 instead of the function. */
2379 static struct z_candidate
*
2380 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2381 const vec
<tree
, va_gc
> *arglist
,
2382 tree access_path
, tree conversion_path
,
2383 tsubst_flags_t complain
)
2385 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2386 int i
, len
, viable
, flags
;
2387 tree parmlist
, parmnode
;
2389 struct rejection_reason
*reason
;
2391 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2392 parmlist
= TREE_TYPE (parmlist
);
2393 parmlist
= TYPE_ARG_TYPES (parmlist
);
2395 len
= vec_safe_length (arglist
) + 1;
2396 convs
= alloc_conversions (len
);
2397 parmnode
= parmlist
;
2399 flags
= LOOKUP_IMPLICIT
;
2402 /* Don't bother looking up the same type twice. */
2403 if (*candidates
&& (*candidates
)->fn
== totype
)
2406 for (i
= 0; i
< len
; ++i
)
2408 tree arg
, argtype
, convert_type
= NULL_TREE
;
2414 arg
= (*arglist
)[i
- 1];
2415 argtype
= lvalue_type (arg
);
2419 t
= build_identity_conv (argtype
, NULL_TREE
);
2420 t
= build_conv (ck_user
, totype
, t
);
2421 /* Leave the 'cand' field null; we'll figure out the conversion in
2422 convert_like_real if this candidate is chosen. */
2423 convert_type
= totype
;
2425 else if (parmnode
== void_list_node
)
2429 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2430 /*c_cast_p=*/false, flags
, complain
);
2431 convert_type
= TREE_VALUE (parmnode
);
2435 t
= build_identity_conv (argtype
, arg
);
2436 t
->ellipsis_p
= true;
2437 convert_type
= argtype
;
2447 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
,
2448 EXPR_LOCATION (arg
));
2455 parmnode
= TREE_CHAIN (parmnode
);
2459 || ! sufficient_parms_p (parmnode
))
2461 int remaining
= remaining_arguments (parmnode
);
2463 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2466 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2467 access_path
, conversion_path
, viable
, reason
, flags
);
2471 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2472 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2473 int flags
, tsubst_flags_t complain
)
2480 struct rejection_reason
*reason
= NULL
;
2485 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2486 convs
= alloc_conversions (num_convs
);
2488 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2489 conversion ops are allowed. We handle that here by just checking for
2490 boolean_type_node because other operators don't ask for it. COND_EXPR
2491 also does contextual conversion to bool for the first operand, but we
2492 handle that in build_conditional_expr, and type1 here is operand 2. */
2493 if (type1
!= boolean_type_node
)
2494 flags
|= LOOKUP_ONLYCONVERTING
;
2496 for (i
= 0; i
< 2; ++i
)
2501 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2502 /*c_cast_p=*/false, flags
, complain
);
2506 /* We need something for printing the candidate. */
2507 t
= build_identity_conv (types
[i
], NULL_TREE
);
2508 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2509 types
[i
], EXPR_LOCATION (args
[i
]));
2514 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2516 EXPR_LOCATION (args
[i
]));
2521 /* For COND_EXPR we rearranged the arguments; undo that now. */
2524 convs
[2] = convs
[1];
2525 convs
[1] = convs
[0];
2526 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2527 /*c_cast_p=*/false, flags
,
2534 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2536 EXPR_LOCATION (args
[2]));
2540 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2542 /*access_path=*/NULL_TREE
,
2543 /*conversion_path=*/NULL_TREE
,
2544 viable
, reason
, flags
);
2548 is_complete (tree t
)
2550 return COMPLETE_TYPE_P (complete_type (t
));
2553 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2556 promoted_arithmetic_type_p (tree type
)
2560 In this section, the term promoted integral type is used to refer
2561 to those integral types which are preserved by integral promotion
2562 (including e.g. int and long but excluding e.g. char).
2563 Similarly, the term promoted arithmetic type refers to promoted
2564 integral types plus floating types. */
2565 return ((CP_INTEGRAL_TYPE_P (type
)
2566 && same_type_p (type_promotes_to (type
), type
))
2567 || TREE_CODE (type
) == REAL_TYPE
);
2570 /* Create any builtin operator overload candidates for the operator in
2571 question given the converted operand types TYPE1 and TYPE2. The other
2572 args are passed through from add_builtin_candidates to
2573 build_builtin_candidate.
2575 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2576 If CODE is requires candidates operands of the same type of the kind
2577 of which TYPE1 and TYPE2 are, we add both candidates
2578 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2581 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2582 enum tree_code code2
, tree fnname
, tree type1
,
2583 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2584 tsubst_flags_t complain
)
2588 case POSTINCREMENT_EXPR
:
2589 case POSTDECREMENT_EXPR
:
2590 args
[1] = integer_zero_node
;
2591 type2
= integer_type_node
;
2600 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2601 and VQ is either volatile or empty, there exist candidate operator
2602 functions of the form
2603 VQ T& operator++(VQ T&);
2604 T operator++(VQ T&, int);
2605 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2606 type other than bool, and VQ is either volatile or empty, there exist
2607 candidate operator functions of the form
2608 VQ T& operator--(VQ T&);
2609 T operator--(VQ T&, int);
2610 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2611 complete object type, and VQ is either volatile or empty, there exist
2612 candidate operator functions of the form
2613 T*VQ& operator++(T*VQ&);
2614 T*VQ& operator--(T*VQ&);
2615 T* operator++(T*VQ&, int);
2616 T* operator--(T*VQ&, int); */
2618 case POSTDECREMENT_EXPR
:
2619 case PREDECREMENT_EXPR
:
2620 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2623 case POSTINCREMENT_EXPR
:
2624 case PREINCREMENT_EXPR
:
2625 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2627 type1
= build_reference_type (type1
);
2632 /* 7 For every cv-qualified or cv-unqualified object type T, there
2633 exist candidate operator functions of the form
2637 8 For every function type T, there exist candidate operator functions of
2639 T& operator*(T*); */
2642 if (TYPE_PTR_P (type1
)
2643 && (TYPE_PTROB_P (type1
)
2644 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2648 /* 9 For every type T, there exist candidate operator functions of the form
2651 10For every promoted arithmetic type T, there exist candidate operator
2652 functions of the form
2656 case UNARY_PLUS_EXPR
: /* unary + */
2657 if (TYPE_PTR_P (type1
))
2661 if (ARITHMETIC_TYPE_P (type1
))
2665 /* 11For every promoted integral type T, there exist candidate operator
2666 functions of the form
2670 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2674 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2675 is the same type as C2 or is a derived class of C2, T is a complete
2676 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2677 there exist candidate operator functions of the form
2678 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2679 where CV12 is the union of CV1 and CV2. */
2682 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2684 tree c1
= TREE_TYPE (type1
);
2685 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2687 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2688 && (TYPE_PTRMEMFUNC_P (type2
)
2689 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2694 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2695 didate operator functions of the form
2700 bool operator<(L, R);
2701 bool operator>(L, R);
2702 bool operator<=(L, R);
2703 bool operator>=(L, R);
2704 bool operator==(L, R);
2705 bool operator!=(L, R);
2706 where LR is the result of the usual arithmetic conversions between
2709 14For every pair of types T and I, where T is a cv-qualified or cv-
2710 unqualified complete object type and I is a promoted integral type,
2711 there exist candidate operator functions of the form
2712 T* operator+(T*, I);
2713 T& operator[](T*, I);
2714 T* operator-(T*, I);
2715 T* operator+(I, T*);
2716 T& operator[](I, T*);
2718 15For every T, where T is a pointer to complete object type, there exist
2719 candidate operator functions of the form112)
2720 ptrdiff_t operator-(T, T);
2722 16For every pointer or enumeration type T, there exist candidate operator
2723 functions of the form
2724 bool operator<(T, T);
2725 bool operator>(T, T);
2726 bool operator<=(T, T);
2727 bool operator>=(T, T);
2728 bool operator==(T, T);
2729 bool operator!=(T, T);
2731 17For every pointer to member type T, there exist candidate operator
2732 functions of the form
2733 bool operator==(T, T);
2734 bool operator!=(T, T); */
2737 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2739 if (TYPE_PTROB_P (type1
)
2740 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2742 type2
= ptrdiff_type_node
;
2747 case TRUNC_DIV_EXPR
:
2748 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2754 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2755 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2757 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2762 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2774 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2776 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2778 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2779 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2781 if (TYPE_PTR_P (type1
)
2782 && null_ptr_cst_p (args
[1]))
2787 if (null_ptr_cst_p (args
[0])
2788 && TYPE_PTR_P (type2
))
2796 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2800 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2802 type1
= ptrdiff_type_node
;
2805 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2807 type2
= ptrdiff_type_node
;
2812 /* 18For every pair of promoted integral types L and R, there exist candi-
2813 date operator functions of the form
2820 where LR is the result of the usual arithmetic conversions between
2823 case TRUNC_MOD_EXPR
:
2829 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2833 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2834 type, VQ is either volatile or empty, and R is a promoted arithmetic
2835 type, there exist candidate operator functions of the form
2836 VQ L& operator=(VQ L&, R);
2837 VQ L& operator*=(VQ L&, R);
2838 VQ L& operator/=(VQ L&, R);
2839 VQ L& operator+=(VQ L&, R);
2840 VQ L& operator-=(VQ L&, R);
2842 20For every pair T, VQ), where T is any type and VQ is either volatile
2843 or empty, there exist candidate operator functions of the form
2844 T*VQ& operator=(T*VQ&, T*);
2846 21For every pair T, VQ), where T is a pointer to member type and VQ is
2847 either volatile or empty, there exist candidate operator functions of
2849 VQ T& operator=(VQ T&, T);
2851 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2852 unqualified complete object type, VQ is either volatile or empty, and
2853 I is a promoted integral type, there exist candidate operator func-
2855 T*VQ& operator+=(T*VQ&, I);
2856 T*VQ& operator-=(T*VQ&, I);
2858 23For every triple L, VQ, R), where L is an integral or enumeration
2859 type, VQ is either volatile or empty, and R is a promoted integral
2860 type, there exist candidate operator functions of the form
2862 VQ L& operator%=(VQ L&, R);
2863 VQ L& operator<<=(VQ L&, R);
2864 VQ L& operator>>=(VQ L&, R);
2865 VQ L& operator&=(VQ L&, R);
2866 VQ L& operator^=(VQ L&, R);
2867 VQ L& operator|=(VQ L&, R); */
2874 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2876 type2
= ptrdiff_type_node
;
2881 case TRUNC_DIV_EXPR
:
2882 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2886 case TRUNC_MOD_EXPR
:
2892 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2897 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2899 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2900 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2901 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2902 || ((TYPE_PTRMEMFUNC_P (type1
)
2903 || TYPE_PTR_P (type1
))
2904 && null_ptr_cst_p (args
[1])))
2914 type1
= build_reference_type (type1
);
2920 For every pair of promoted arithmetic types L and R, there
2921 exist candidate operator functions of the form
2923 LR operator?(bool, L, R);
2925 where LR is the result of the usual arithmetic conversions
2926 between types L and R.
2928 For every type T, where T is a pointer or pointer-to-member
2929 type, there exist candidate operator functions of the form T
2930 operator?(bool, T, T); */
2932 if (promoted_arithmetic_type_p (type1
)
2933 && promoted_arithmetic_type_p (type2
))
2937 /* Otherwise, the types should be pointers. */
2938 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2941 /* We don't check that the two types are the same; the logic
2942 below will actually create two candidates; one in which both
2943 parameter types are TYPE1, and one in which both parameter
2949 if (ARITHMETIC_TYPE_P (type1
))
2957 /* Make sure we don't create builtin candidates with dependent types. */
2958 bool u1
= uses_template_parms (type1
);
2959 bool u2
= type2
? uses_template_parms (type2
) : false;
2962 /* Try to recover if one of the types is non-dependent. But if
2963 there's only one type, there's nothing we can do. */
2966 /* And we lose if both are dependent. */
2969 /* Or if they have different forms. */
2970 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2979 /* If we're dealing with two pointer types or two enumeral types,
2980 we need candidates for both of them. */
2981 if (type2
&& !same_type_p (type1
, type2
)
2982 && TREE_CODE (type1
) == TREE_CODE (type2
)
2983 && (TYPE_REF_P (type1
)
2984 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2985 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2986 || TYPE_PTRMEMFUNC_P (type1
)
2987 || MAYBE_CLASS_TYPE_P (type1
)
2988 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2990 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2992 tree cptype
= composite_pointer_type (type1
, type2
,
2997 if (cptype
!= error_mark_node
)
2999 build_builtin_candidate
3000 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
3006 build_builtin_candidate
3007 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
3008 build_builtin_candidate
3009 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
3013 build_builtin_candidate
3014 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
3018 type_decays_to (tree type
)
3020 if (TREE_CODE (type
) == ARRAY_TYPE
)
3021 return build_pointer_type (TREE_TYPE (type
));
3022 if (TREE_CODE (type
) == FUNCTION_TYPE
)
3023 return build_pointer_type (type
);
3027 /* There are three conditions of builtin candidates:
3029 1) bool-taking candidates. These are the same regardless of the input.
3030 2) pointer-pair taking candidates. These are generated for each type
3031 one of the input types converts to.
3032 3) arithmetic candidates. According to the standard, we should generate
3033 all of these, but I'm trying not to...
3035 Here we generate a superset of the possible candidates for this particular
3036 case. That is a subset of the full set the standard defines, plus some
3037 other cases which the standard disallows. add_builtin_candidate will
3038 filter out the invalid set. */
3041 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
3042 enum tree_code code2
, tree fnname
, tree
*args
,
3043 int flags
, tsubst_flags_t complain
)
3047 tree type
, argtypes
[3], t
;
3048 /* TYPES[i] is the set of possible builtin-operator parameter types
3049 we will consider for the Ith argument. */
3050 vec
<tree
, va_gc
> *types
[2];
3053 for (i
= 0; i
< 3; ++i
)
3056 argtypes
[i
] = unlowered_expr_type (args
[i
]);
3058 argtypes
[i
] = NULL_TREE
;
3063 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
3064 and VQ is either volatile or empty, there exist candidate operator
3065 functions of the form
3066 VQ T& operator++(VQ T&); */
3068 case POSTINCREMENT_EXPR
:
3069 case PREINCREMENT_EXPR
:
3070 case POSTDECREMENT_EXPR
:
3071 case PREDECREMENT_EXPR
:
3076 /* 24There also exist candidate operator functions of the form
3077 bool operator!(bool);
3078 bool operator&&(bool, bool);
3079 bool operator||(bool, bool); */
3081 case TRUTH_NOT_EXPR
:
3082 build_builtin_candidate
3083 (candidates
, fnname
, boolean_type_node
,
3084 NULL_TREE
, args
, argtypes
, flags
, complain
);
3087 case TRUTH_ORIF_EXPR
:
3088 case TRUTH_ANDIF_EXPR
:
3089 build_builtin_candidate
3090 (candidates
, fnname
, boolean_type_node
,
3091 boolean_type_node
, args
, argtypes
, flags
, complain
);
3113 types
[0] = make_tree_vector ();
3114 types
[1] = make_tree_vector ();
3116 for (i
= 0; i
< 2; ++i
)
3120 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
3124 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
3127 convs
= lookup_conversions (argtypes
[i
]);
3129 if (code
== COND_EXPR
)
3131 if (lvalue_p (args
[i
]))
3132 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3134 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3140 for (; convs
; convs
= TREE_CHAIN (convs
))
3142 type
= TREE_TYPE (convs
);
3145 && (!TYPE_REF_P (type
)
3146 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3149 if (code
== COND_EXPR
&& TYPE_REF_P (type
))
3150 vec_safe_push (types
[i
], type
);
3152 type
= non_reference (type
);
3153 if (i
!= 0 || ! ref1
)
3155 type
= cv_unqualified (type_decays_to (type
));
3156 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3157 vec_safe_push (types
[i
], type
);
3158 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3159 type
= type_promotes_to (type
);
3162 if (! vec_member (type
, types
[i
]))
3163 vec_safe_push (types
[i
], type
);
3168 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3169 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3170 type
= non_reference (argtypes
[i
]);
3171 if (i
!= 0 || ! ref1
)
3173 type
= cv_unqualified (type_decays_to (type
));
3174 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3175 vec_safe_push (types
[i
], type
);
3176 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3177 type
= type_promotes_to (type
);
3179 vec_safe_push (types
[i
], type
);
3183 /* Run through the possible parameter types of both arguments,
3184 creating candidates with those parameter types. */
3185 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3190 if (!types
[1]->is_empty ())
3191 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3192 add_builtin_candidate
3193 (candidates
, code
, code2
, fnname
, t
,
3194 u
, args
, argtypes
, flags
, complain
);
3196 add_builtin_candidate
3197 (candidates
, code
, code2
, fnname
, t
,
3198 NULL_TREE
, args
, argtypes
, flags
, complain
);
3201 release_tree_vector (types
[0]);
3202 release_tree_vector (types
[1]);
3206 /* If TMPL can be successfully instantiated as indicated by
3207 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3209 TMPL is the template. EXPLICIT_TARGS are any explicit template
3210 arguments. ARGLIST is the arguments provided at the call-site.
3211 This does not change ARGLIST. The RETURN_TYPE is the desired type
3212 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3213 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3214 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3216 static struct z_candidate
*
3217 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3218 tree ctype
, tree explicit_targs
, tree first_arg
,
3219 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3220 tree access_path
, tree conversion_path
,
3221 int flags
, tree obj
, unification_kind_t strict
,
3222 tsubst_flags_t complain
)
3224 int ntparms
= DECL_NTPARMS (tmpl
);
3225 tree targs
= make_tree_vec (ntparms
);
3226 unsigned int len
= vec_safe_length (arglist
);
3227 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3228 unsigned int skip_without_in_chrg
= 0;
3229 tree first_arg_without_in_chrg
= first_arg
;
3230 tree
*args_without_in_chrg
;
3231 unsigned int nargs_without_in_chrg
;
3232 unsigned int ia
, ix
;
3234 struct z_candidate
*cand
;
3236 struct rejection_reason
*reason
= NULL
;
3238 conversion
**convs
= NULL
;
3240 /* We don't do deduction on the in-charge parameter, the VTT
3241 parameter or 'this'. */
3242 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3244 if (first_arg_without_in_chrg
!= NULL_TREE
)
3245 first_arg_without_in_chrg
= NULL_TREE
;
3246 else if (return_type
&& strict
== DEDUCE_CALL
)
3247 /* We're deducing for a call to the result of a template conversion
3248 function, so the args don't contain 'this'; leave them alone. */;
3250 ++skip_without_in_chrg
;
3253 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3254 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3255 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3257 if (first_arg_without_in_chrg
!= NULL_TREE
)
3258 first_arg_without_in_chrg
= NULL_TREE
;
3260 ++skip_without_in_chrg
;
3263 if (len
< skip_without_in_chrg
)
3266 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3267 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3268 TREE_TYPE ((*arglist
)[0])))
3270 /* 12.8/6 says, "A declaration of a constructor for a class X is
3271 ill-formed if its first parameter is of type (optionally cv-qualified)
3272 X and either there are no other parameters or else all other
3273 parameters have default arguments. A member function template is never
3274 instantiated to produce such a constructor signature."
3276 So if we're trying to copy an object of the containing class, don't
3277 consider a template constructor that has a first parameter type that
3278 is just a template parameter, as we would deduce a signature that we
3279 would then reject in the code below. */
3280 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3282 firstparm
= TREE_VALUE (firstparm
);
3283 if (PACK_EXPANSION_P (firstparm
))
3284 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3285 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3287 gcc_assert (!explicit_targs
);
3288 reason
= invalid_copy_with_fn_template_rejection ();
3294 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3295 + (len
- skip_without_in_chrg
));
3296 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3298 if (first_arg_without_in_chrg
!= NULL_TREE
)
3300 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3303 for (ix
= skip_without_in_chrg
;
3304 vec_safe_iterate (arglist
, ix
, &arg
);
3307 args_without_in_chrg
[ia
] = arg
;
3310 gcc_assert (ia
== nargs_without_in_chrg
);
3312 errs
= errorcount
+sorrycount
;
3314 convs
= alloc_conversions (nargs
);
3315 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3316 args_without_in_chrg
,
3317 nargs_without_in_chrg
,
3318 return_type
, strict
, flags
, convs
,
3319 false, complain
& tf_decltype
);
3321 if (fn
== error_mark_node
)
3323 /* Don't repeat unification later if it already resulted in errors. */
3324 if (errorcount
+sorrycount
== errs
)
3325 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3326 targs
, args_without_in_chrg
,
3327 nargs_without_in_chrg
,
3328 return_type
, strict
, flags
);
3330 reason
= template_unification_error_rejection ();
3334 /* Now the explicit specifier might have been deduced; check if this
3335 declaration is explicit. If it is and we're ignoring non-converting
3336 constructors, don't add this function to the set of candidates. */
3337 if ((flags
& LOOKUP_ONLYCONVERTING
) && DECL_NONCONVERTING_P (fn
))
3340 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3342 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3343 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3346 /* We're trying to produce a constructor with a prohibited signature,
3347 as discussed above; handle here any cases we didn't catch then,
3349 reason
= invalid_copy_with_fn_template_rejection ();
3354 if (obj
!= NULL_TREE
)
3355 /* Aha, this is a conversion function. */
3356 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3357 access_path
, conversion_path
, complain
);
3359 cand
= add_function_candidate (candidates
, fn
, ctype
,
3360 first_arg
, arglist
, access_path
,
3361 conversion_path
, flags
, convs
, complain
);
3362 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3363 /* This situation can occur if a member template of a template
3364 class is specialized. Then, instantiate_template might return
3365 an instantiation of the specialization, in which case the
3366 DECL_TI_TEMPLATE field will point at the original
3367 specialization. For example:
3369 template <class T> struct S { template <class U> void f(U);
3370 template <> void f(int) {}; };
3374 Here, TMPL will be template <class U> S<double>::f(U).
3375 And, instantiate template will give us the specialization
3376 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3377 for this will point at template <class T> template <> S<T>::f(int),
3378 so that we can find the definition. For the purposes of
3379 overload resolution, however, we want the original TMPL. */
3380 cand
->template_decl
= build_template_info (tmpl
, targs
);
3382 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3383 cand
->explicit_targs
= explicit_targs
;
3387 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3388 access_path
, conversion_path
, 0, reason
, flags
);
3392 static struct z_candidate
*
3393 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3394 tree explicit_targs
, tree first_arg
,
3395 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3396 tree access_path
, tree conversion_path
, int flags
,
3397 unification_kind_t strict
, tsubst_flags_t complain
)
3400 add_template_candidate_real (candidates
, tmpl
, ctype
,
3401 explicit_targs
, first_arg
, arglist
,
3402 return_type
, access_path
, conversion_path
,
3403 flags
, NULL_TREE
, strict
, complain
);
3406 /* Create an overload candidate for the conversion function template TMPL,
3407 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3408 pointer-to-function which will in turn be called with the argument list
3409 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3410 passed on to implicit_conversion. */
3412 static struct z_candidate
*
3413 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3415 const vec
<tree
, va_gc
> *arglist
,
3416 tree return_type
, tree access_path
,
3417 tree conversion_path
, tsubst_flags_t complain
)
3419 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3420 core issue 2189, let's disable this candidate if there are any call
3426 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3427 NULL_TREE
, arglist
, return_type
, access_path
,
3428 conversion_path
, 0, obj
, DEDUCE_CALL
,
3432 /* The CANDS are the set of candidates that were considered for
3433 overload resolution. Return the set of viable candidates, or CANDS
3434 if none are viable. If any of the candidates were viable, set
3435 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3436 considered viable only if it is strictly viable. */
3438 static struct z_candidate
*
3439 splice_viable (struct z_candidate
*cands
,
3443 struct z_candidate
*viable
;
3444 struct z_candidate
**last_viable
;
3445 struct z_candidate
**cand
;
3446 bool found_strictly_viable
= false;
3448 /* Be strict inside templates, since build_over_call won't actually
3449 do the conversions to get pedwarns. */
3450 if (processing_template_decl
)
3454 last_viable
= &viable
;
3455 *any_viable_p
= false;
3460 struct z_candidate
*c
= *cand
;
3462 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3464 /* Be strict in the presence of a viable candidate. Also if
3465 there are template candidates, so that we get deduction errors
3466 for them instead of silently preferring a bad conversion. */
3468 if (viable
&& !found_strictly_viable
)
3470 /* Put any spliced near matches back onto the main list so
3471 that we see them if there is no strict match. */
3472 *any_viable_p
= false;
3473 *last_viable
= cands
;
3476 last_viable
= &viable
;
3480 if (strict_p
? c
->viable
== 1 : c
->viable
)
3485 last_viable
= &c
->next
;
3486 *any_viable_p
= true;
3488 found_strictly_viable
= true;
3494 return viable
? viable
: cands
;
3498 any_strictly_viable (struct z_candidate
*cands
)
3500 for (; cands
; cands
= cands
->next
)
3501 if (cands
->viable
== 1)
3506 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3507 words, it is about to become the "this" pointer for a member
3508 function call. Take the address of the object. */
3511 build_this (tree obj
)
3513 /* In a template, we are only concerned about the type of the
3514 expression, so we can take a shortcut. */
3515 if (processing_template_decl
)
3516 return build_address (obj
);
3518 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3521 /* Returns true iff functions are equivalent. Equivalent functions are
3522 not '==' only if one is a function-local extern function or if
3523 both are extern "C". */
3526 equal_functions (tree fn1
, tree fn2
)
3528 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3530 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3532 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3533 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3534 return decls_match (fn1
, fn2
);
3538 /* Print information about a candidate FN being rejected due to INFO. */
3541 print_conversion_rejection (location_t loc
, struct conversion_info
*info
,
3544 tree from
= info
->from
;
3546 from
= lvalue_type (from
);
3547 if (info
->n_arg
== -1)
3549 /* Conversion of implicit `this' argument failed. */
3550 if (!TYPE_P (info
->from
))
3551 /* A bad conversion for 'this' must be discarding cv-quals. */
3552 inform (loc
, " passing %qT as %<this%> "
3553 "argument discards qualifiers",
3556 inform (loc
, " no known conversion for implicit "
3557 "%<this%> parameter from %qH to %qI",
3558 from
, info
->to_type
);
3560 else if (!TYPE_P (info
->from
))
3562 if (info
->n_arg
>= 0)
3563 inform (loc
, " conversion of argument %d would be ill-formed:",
3565 perform_implicit_conversion (info
->to_type
, info
->from
,
3566 tf_warning_or_error
);
3568 else if (info
->n_arg
== -2)
3569 /* Conversion of conversion function return value failed. */
3570 inform (loc
, " no known conversion from %qH to %qI",
3571 from
, info
->to_type
);
3574 if (TREE_CODE (fn
) == FUNCTION_DECL
)
3575 loc
= get_fndecl_argument_location (fn
, info
->n_arg
);
3576 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3577 info
->n_arg
+ 1, from
, info
->to_type
);
3581 /* Print information about a candidate with WANT parameters and we found
3585 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3587 inform_n (loc
, want
,
3588 " candidate expects %d argument, %d provided",
3589 " candidate expects %d arguments, %d provided",
3593 /* Print information about one overload candidate CANDIDATE. MSGSTR
3594 is the text to print before the candidate itself.
3596 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3597 to have been run through gettext by the caller. This wart makes
3598 life simpler in print_z_candidates and for the translators. */
3601 print_z_candidate (location_t loc
, const char *msgstr
,
3602 struct z_candidate
*candidate
)
3604 const char *msg
= (msgstr
== NULL
3606 : ACONCAT ((msgstr
, " ", NULL
)));
3607 tree fn
= candidate
->fn
;
3608 if (flag_new_inheriting_ctors
)
3609 fn
= strip_inheriting_ctors (fn
);
3610 location_t cloc
= location_of (fn
);
3612 if (identifier_p (fn
))
3615 if (candidate
->num_convs
== 3)
3616 inform (cloc
, "%s%<%D(%T, %T, %T)%> <built-in>", msg
, fn
,
3617 candidate
->convs
[0]->type
,
3618 candidate
->convs
[1]->type
,
3619 candidate
->convs
[2]->type
);
3620 else if (candidate
->num_convs
== 2)
3621 inform (cloc
, "%s%<%D(%T, %T)%> <built-in>", msg
, fn
,
3622 candidate
->convs
[0]->type
,
3623 candidate
->convs
[1]->type
);
3625 inform (cloc
, "%s%<%D(%T)%> <built-in>", msg
, fn
,
3626 candidate
->convs
[0]->type
);
3628 else if (TYPE_P (fn
))
3629 inform (cloc
, "%s%qT <conversion>", msg
, fn
);
3630 else if (candidate
->viable
== -1)
3631 inform (cloc
, "%s%#qD <near match>", msg
, fn
);
3632 else if (DECL_DELETED_FN (fn
))
3633 inform (cloc
, "%s%#qD <deleted>", msg
, fn
);
3635 inform (cloc
, "%s%#qD", msg
, fn
);
3636 if (fn
!= candidate
->fn
)
3638 cloc
= location_of (candidate
->fn
);
3639 inform (cloc
, " inherited here");
3641 /* Give the user some information about why this candidate failed. */
3642 if (candidate
->reason
!= NULL
)
3644 struct rejection_reason
*r
= candidate
->reason
;
3649 print_arity_information (cloc
, r
->u
.arity
.actual
,
3650 r
->u
.arity
.expected
);
3652 case rr_arg_conversion
:
3653 print_conversion_rejection (cloc
, &r
->u
.conversion
, fn
);
3655 case rr_bad_arg_conversion
:
3656 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
, fn
);
3658 case rr_explicit_conversion
:
3659 inform (cloc
, " return type %qT of explicit conversion function "
3660 "cannot be converted to %qT with a qualification "
3661 "conversion", r
->u
.conversion
.from
,
3662 r
->u
.conversion
.to_type
);
3664 case rr_template_conversion
:
3665 inform (cloc
, " conversion from return type %qT of template "
3666 "conversion function specialization to %qT is not an "
3667 "exact match", r
->u
.conversion
.from
,
3668 r
->u
.conversion
.to_type
);
3670 case rr_template_unification
:
3671 /* We use template_unification_error_rejection if unification caused
3672 actual non-SFINAE errors, in which case we don't need to repeat
3674 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3676 inform (cloc
, " substitution of deduced template arguments "
3677 "resulted in errors seen above");
3680 /* Re-run template unification with diagnostics. */
3681 inform (cloc
, " template argument deduction/substitution failed:");
3682 fn_type_unification (r
->u
.template_unification
.tmpl
,
3683 r
->u
.template_unification
.explicit_targs
,
3685 (r
->u
.template_unification
.num_targs
)),
3686 r
->u
.template_unification
.args
,
3687 r
->u
.template_unification
.nargs
,
3688 r
->u
.template_unification
.return_type
,
3689 r
->u
.template_unification
.strict
,
3690 r
->u
.template_unification
.flags
,
3693 case rr_invalid_copy
:
3695 " a constructor taking a single argument of its own "
3696 "class type is invalid");
3698 case rr_constraint_failure
:
3700 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3701 tree args
= r
->u
.template_instantiation
.targs
;
3702 diagnose_constraints (cloc
, tmpl
, args
);
3705 case rr_inherited_ctor
:
3706 inform (cloc
, " an inherited constructor is not a candidate for "
3707 "initialization from an expression of the same or derived "
3712 /* This candidate didn't have any issues or we failed to
3713 handle a particular code. Either way... */
3720 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3722 struct z_candidate
*cand1
;
3723 struct z_candidate
**cand2
;
3728 /* Remove non-viable deleted candidates. */
3730 for (cand2
= &cand1
; *cand2
; )
3732 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3733 && !(*cand2
)->viable
3734 && DECL_DELETED_FN ((*cand2
)->fn
))
3735 *cand2
= (*cand2
)->next
;
3737 cand2
= &(*cand2
)->next
;
3739 /* ...if there are any non-deleted ones. */
3743 /* There may be duplicates in the set of candidates. We put off
3744 checking this condition as long as possible, since we have no way
3745 to eliminate duplicates from a set of functions in less than n^2
3746 time. Now we are about to emit an error message, so it is more
3747 permissible to go slowly. */
3748 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3750 tree fn
= cand1
->fn
;
3751 /* Skip builtin candidates and conversion functions. */
3754 cand2
= &cand1
->next
;
3757 if (DECL_P ((*cand2
)->fn
)
3758 && equal_functions (fn
, (*cand2
)->fn
))
3759 *cand2
= (*cand2
)->next
;
3761 cand2
= &(*cand2
)->next
;
3765 for (; candidates
; candidates
= candidates
->next
)
3766 print_z_candidate (loc
, "candidate:", candidates
);
3769 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3770 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3771 the result of the conversion function to convert it to the final
3772 desired type. Merge the two sequences into a single sequence,
3773 and return the merged sequence. */
3776 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3779 bool bad
= user_seq
->bad_p
;
3781 gcc_assert (user_seq
->kind
== ck_user
);
3783 /* Find the end of the second conversion sequence. */
3784 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3786 /* The entire sequence is a user-conversion sequence. */
3787 (*t
)->user_conv_p
= true;
3792 if ((*t
)->rvaluedness_matches_p
)
3793 /* We're binding a reference directly to the result of the conversion.
3794 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3795 type, but we want it back. */
3796 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3798 /* Replace the identity conversion with the user conversion
3805 /* Handle overload resolution for initializing an object of class type from
3806 an initializer list. First we look for a suitable constructor that
3807 takes a std::initializer_list; if we don't find one, we then look for a
3808 non-list constructor.
3810 Parameters are as for add_candidates, except that the arguments are in
3811 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3812 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3815 add_list_candidates (tree fns
, tree first_arg
,
3816 const vec
<tree
, va_gc
> *args
, tree totype
,
3817 tree explicit_targs
, bool template_only
,
3818 tree conversion_path
, tree access_path
,
3820 struct z_candidate
**candidates
,
3821 tsubst_flags_t complain
)
3823 gcc_assert (*candidates
== NULL
);
3825 /* We're looking for a ctor for list-initialization. */
3826 flags
|= LOOKUP_LIST_INIT_CTOR
;
3827 /* And we don't allow narrowing conversions. We also use this flag to
3828 avoid the copy constructor call for copy-list-initialization. */
3829 flags
|= LOOKUP_NO_NARROWING
;
3831 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3832 tree init_list
= (*args
)[nart
];
3834 /* Always use the default constructor if the list is empty (DR 990). */
3835 if (CONSTRUCTOR_NELTS (init_list
) == 0
3836 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3838 /* If the class has a list ctor, try passing the list as a single
3839 argument first, but only consider list ctors. */
3840 else if (TYPE_HAS_LIST_CTOR (totype
))
3842 flags
|= LOOKUP_LIST_ONLY
;
3843 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3844 explicit_targs
, template_only
, conversion_path
,
3845 access_path
, flags
, candidates
, complain
);
3846 if (any_strictly_viable (*candidates
))
3850 /* Expand the CONSTRUCTOR into a new argument vec. */
3851 vec
<tree
, va_gc
> *new_args
;
3852 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3853 for (unsigned i
= 0; i
< nart
; ++i
)
3854 new_args
->quick_push ((*args
)[i
]);
3855 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3856 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3858 /* We aren't looking for list-ctors anymore. */
3859 flags
&= ~LOOKUP_LIST_ONLY
;
3860 /* We allow more user-defined conversions within an init-list. */
3861 flags
&= ~LOOKUP_NO_CONVERSION
;
3863 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3864 explicit_targs
, template_only
, conversion_path
,
3865 access_path
, flags
, candidates
, complain
);
3868 /* Returns the best overload candidate to perform the requested
3869 conversion. This function is used for three the overloading situations
3870 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3871 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3872 per [dcl.init.ref], so we ignore temporary bindings. */
3874 static struct z_candidate
*
3875 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3876 tsubst_flags_t complain
)
3878 struct z_candidate
*candidates
, *cand
;
3880 tree ctors
= NULL_TREE
;
3881 tree conv_fns
= NULL_TREE
;
3882 conversion
*conv
= NULL
;
3883 tree first_arg
= NULL_TREE
;
3884 vec
<tree
, va_gc
> *args
= NULL
;
3891 fromtype
= TREE_TYPE (expr
);
3893 /* We represent conversion within a hierarchy using RVALUE_CONV and
3894 BASE_CONV, as specified by [over.best.ics]; these become plain
3895 constructor calls, as specified in [dcl.init]. */
3896 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3897 || !DERIVED_FROM_P (totype
, fromtype
));
3899 if (CLASS_TYPE_P (totype
))
3900 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3901 creating a garbage BASELINK; constructors can't be inherited. */
3902 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3904 if (MAYBE_CLASS_TYPE_P (fromtype
))
3906 tree to_nonref
= non_reference (totype
);
3907 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3908 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3909 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3911 /* [class.conv.fct] A conversion function is never used to
3912 convert a (possibly cv-qualified) object to the (possibly
3913 cv-qualified) same object type (or a reference to it), to a
3914 (possibly cv-qualified) base class of that type (or a
3915 reference to it)... */
3918 conv_fns
= lookup_conversions (fromtype
);
3922 flags
|= LOOKUP_NO_CONVERSION
;
3923 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3924 flags
|= LOOKUP_NO_NARROWING
;
3926 /* It's OK to bind a temporary for converting constructor arguments, but
3927 not in converting the return value of a conversion operator. */
3928 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3929 | (flags
& LOOKUP_NO_NARROWING
));
3930 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3934 int ctorflags
= flags
;
3936 first_arg
= build_dummy_object (totype
);
3938 /* We should never try to call the abstract or base constructor
3940 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3941 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3943 args
= make_tree_vector_single (expr
);
3944 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3946 /* List-initialization. */
3947 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3948 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3949 ctorflags
, &candidates
, complain
);
3953 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3954 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3955 ctorflags
, &candidates
, complain
);
3958 for (cand
= candidates
; cand
; cand
= cand
->next
)
3960 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3962 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3963 set, then this is copy-initialization. In that case, "The
3964 result of the call is then used to direct-initialize the
3965 object that is the destination of the copy-initialization."
3968 We represent this in the conversion sequence with an
3969 rvalue conversion, which means a constructor call. */
3970 if (!TYPE_REF_P (totype
)
3971 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3973 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3979 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3980 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3985 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3987 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3988 struct z_candidate
*old_candidates
;
3990 /* If we are called to convert to a reference type, we are trying to
3991 find a direct binding, so don't even consider temporaries. If
3992 we don't find a direct binding, the caller will try again to
3993 look for a temporary binding. */
3994 if (TYPE_REF_P (totype
))
3995 convflags
|= LOOKUP_NO_TEMP_BIND
;
3997 old_candidates
= candidates
;
3998 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
4000 conversion_path
, TYPE_BINFO (fromtype
),
4001 flags
, &candidates
, complain
);
4003 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
4005 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
4007 = implicit_conversion (totype
,
4010 /*c_cast_p=*/false, convflags
,
4013 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
4014 copy-initialization. In that case, "The result of the
4015 call is then used to direct-initialize the object that is
4016 the destination of the copy-initialization." [dcl.init]
4018 We represent this in the conversion sequence with an
4019 rvalue conversion, which means a constructor call. But
4020 don't add a second rvalue conversion if there's already
4021 one there. Which there really shouldn't be, but it's
4022 harmless since we'd add it here anyway. */
4023 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
4024 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
4025 ics
= build_conv (ck_rvalue
, totype
, ics
);
4027 cand
->second_conv
= ics
;
4032 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
4034 EXPR_LOCATION (expr
));
4036 else if (TYPE_REF_P (totype
) && !ics
->rvaluedness_matches_p
4037 && TREE_CODE (TREE_TYPE (totype
)) != FUNCTION_TYPE
)
4039 /* If we are called to convert to a reference type, we are trying
4040 to find a direct binding per [over.match.ref], so rvaluedness
4041 must match for non-functions. */
4044 else if (DECL_NONCONVERTING_P (cand
->fn
)
4045 && ics
->rank
> cr_exact
)
4047 /* 13.3.1.5: For direct-initialization, those explicit
4048 conversion functions that are not hidden within S and
4049 yield type T or a type that can be converted to type T
4050 with a qualification conversion (4.4) are also candidate
4052 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
4053 I've raised this issue with the committee. --jason 9/2011 */
4055 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
4057 else if (cand
->viable
== 1 && ics
->bad_p
)
4061 = bad_arg_conversion_rejection (NULL_TREE
, -2,
4063 EXPR_LOCATION (expr
));
4065 else if (primary_template_specialization_p (cand
->fn
)
4066 && ics
->rank
> cr_exact
)
4068 /* 13.3.3.1.2: If the user-defined conversion is specified by
4069 a specialization of a conversion function template, the
4070 second standard conversion sequence shall have exact match
4073 cand
->reason
= template_conversion_rejection (rettype
, totype
);
4078 candidates
= splice_viable (candidates
, false, &any_viable_p
);
4082 release_tree_vector (args
);
4086 cand
= tourney (candidates
, complain
);
4089 if (complain
& tf_error
)
4091 auto_diagnostic_group d
;
4092 error ("conversion from %qH to %qI is ambiguous",
4094 print_z_candidates (location_of (expr
), candidates
);
4097 cand
= candidates
; /* any one will do */
4098 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
4099 cand
->second_conv
->user_conv_p
= true;
4100 if (!any_strictly_viable (candidates
))
4101 cand
->second_conv
->bad_p
= true;
4102 if (flags
& LOOKUP_ONLYCONVERTING
)
4103 cand
->second_conv
->need_temporary_p
= true;
4104 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
4105 ambiguous conversion is no worse than another user-defined
4112 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
4113 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
4114 else if (cand
->second_conv
->kind
== ck_rvalue
)
4115 /* DR 5: [in the first step of copy-initialization]...if the function
4116 is a constructor, the call initializes a temporary of the
4117 cv-unqualified version of the destination type. */
4118 convtype
= cv_unqualified (totype
);
4121 /* Build the user conversion sequence. */
4125 build_identity_conv (TREE_TYPE (expr
), expr
));
4127 if (cand
->viable
== -1)
4130 /* We're performing the maybe-rvalue overload resolution and
4131 a conversion function is in play. Reject converting the return
4132 value of the conversion function to a base class. */
4133 if ((flags
& LOOKUP_PREFER_RVALUE
) && !DECL_CONSTRUCTOR_P (cand
->fn
))
4134 for (conversion
*t
= cand
->second_conv
; t
; t
= next_conversion (t
))
4135 if (t
->kind
== ck_base
)
4138 /* Remember that this was a list-initialization. */
4139 if (flags
& LOOKUP_NO_NARROWING
)
4140 conv
->check_narrowing
= true;
4142 /* Combine it with the second conversion sequence. */
4143 cand
->second_conv
= merge_conversion_sequences (conv
,
4149 /* Wrapper for above. */
4152 build_user_type_conversion (tree totype
, tree expr
, int flags
,
4153 tsubst_flags_t complain
)
4155 struct z_candidate
*cand
;
4158 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4159 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
4163 if (cand
->second_conv
->kind
== ck_ambig
)
4164 ret
= error_mark_node
;
4167 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4168 ret
= convert_from_reference (expr
);
4174 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4178 /* Worker for build_converted_constant_expr. */
4181 build_converted_constant_expr_internal (tree type
, tree expr
,
4182 int flags
, tsubst_flags_t complain
)
4187 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
4189 if (error_operand_p (expr
))
4190 return error_mark_node
;
4192 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4193 p
= conversion_obstack_alloc (0);
4195 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4196 /*c_cast_p=*/false, flags
, complain
);
4198 /* A converted constant expression of type T is an expression, implicitly
4199 converted to type T, where the converted expression is a constant
4200 expression and the implicit conversion sequence contains only
4202 * user-defined conversions,
4203 * lvalue-to-rvalue conversions (7.1),
4204 * array-to-pointer conversions (7.2),
4205 * function-to-pointer conversions (7.3),
4206 * qualification conversions (7.5),
4207 * integral promotions (7.6),
4208 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4209 * null pointer conversions (7.11) from std::nullptr_t,
4210 * null member pointer conversions (7.12) from std::nullptr_t, and
4211 * function pointer conversions (7.13),
4213 and where the reference binding (if any) binds directly. */
4215 for (conversion
*c
= conv
;
4216 conv
&& c
->kind
!= ck_identity
;
4217 c
= next_conversion (c
))
4221 /* A conversion function is OK. If it isn't constexpr, we'll
4222 complain later that the argument isn't constant. */
4224 /* The lvalue-to-rvalue conversion is OK. */
4226 /* Array-to-pointer and function-to-pointer. */
4228 /* Function pointer conversions. */
4230 /* Qualification conversions. */
4235 if (c
->need_temporary_p
)
4237 if (complain
& tf_error
)
4238 error_at (loc
, "initializing %qH with %qI in converted "
4239 "constant expression does not bind directly",
4240 type
, next_conversion (c
)->type
);
4249 t
= next_conversion (c
)->type
;
4250 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4251 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4252 /* Integral promotion or conversion. */
4254 if (NULLPTR_TYPE_P (t
))
4255 /* Conversion from nullptr to pointer or pointer-to-member. */
4258 if (complain
& tf_error
)
4259 error_at (loc
, "conversion from %qH to %qI in a "
4260 "converted constant expression", t
, type
);
4269 /* Avoid confusing convert_nontype_argument by introducing
4270 a redundant conversion to the same reference type. */
4271 if (conv
&& conv
->kind
== ck_ref_bind
4272 && REFERENCE_REF_P (expr
))
4274 tree ref
= TREE_OPERAND (expr
, 0);
4275 if (same_type_p (type
, TREE_TYPE (ref
)))
4281 conv
->check_narrowing
= true;
4282 conv
->check_narrowing_const_only
= true;
4283 expr
= convert_like (conv
, expr
, complain
);
4287 if (complain
& tf_error
)
4288 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4289 TREE_TYPE (expr
), type
);
4290 expr
= error_mark_node
;
4293 /* Free all the conversions we allocated. */
4294 obstack_free (&conversion_obstack
, p
);
4299 /* Subroutine of convert_nontype_argument.
4301 EXPR is an expression used in a context that requires a converted
4302 constant-expression, such as a template non-type parameter. Do any
4303 necessary conversions (that are permitted for converted
4304 constant-expressions) to convert it to the desired type.
4306 This function doesn't consider explicit conversion functions. If
4307 you mean to use "a contextually converted constant expression of type
4308 bool", use build_converted_constant_bool_expr.
4310 If conversion is successful, returns the converted expression;
4311 otherwise, returns error_mark_node. */
4314 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4316 return build_converted_constant_expr_internal (type
, expr
, LOOKUP_IMPLICIT
,
4320 /* Used to create "a contextually converted constant expression of type
4321 bool". This differs from build_converted_constant_expr in that it
4322 also considers explicit conversion functions. */
4325 build_converted_constant_bool_expr (tree expr
, tsubst_flags_t complain
)
4327 return build_converted_constant_expr_internal (boolean_type_node
, expr
,
4328 LOOKUP_NORMAL
, complain
);
4331 /* Do any initial processing on the arguments to a function call. */
4333 static vec
<tree
, va_gc
> *
4334 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4339 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4341 if (error_operand_p (arg
))
4343 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4345 if (complain
& tf_error
)
4346 error ("invalid use of void expression");
4349 else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg
), arg
, complain
))
4355 /* Perform overload resolution on FN, which is called with the ARGS.
4357 Return the candidate function selected by overload resolution, or
4358 NULL if the event that overload resolution failed. In the case
4359 that overload resolution fails, *CANDIDATES will be the set of
4360 candidates considered, and ANY_VIABLE_P will be set to true or
4361 false to indicate whether or not any of the candidates were
4364 The ARGS should already have gone through RESOLVE_ARGS before this
4365 function is called. */
4367 static struct z_candidate
*
4368 perform_overload_resolution (tree fn
,
4369 const vec
<tree
, va_gc
> *args
,
4370 struct z_candidate
**candidates
,
4371 bool *any_viable_p
, tsubst_flags_t complain
)
4373 struct z_candidate
*cand
;
4374 tree explicit_targs
;
4377 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4379 explicit_targs
= NULL_TREE
;
4383 *any_viable_p
= true;
4386 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4387 || TREE_CODE (fn
) == TEMPLATE_DECL
4388 || TREE_CODE (fn
) == OVERLOAD
4389 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4391 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4393 explicit_targs
= TREE_OPERAND (fn
, 1);
4394 fn
= TREE_OPERAND (fn
, 0);
4398 /* Add the various candidate functions. */
4399 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4400 explicit_targs
, template_only
,
4401 /*conversion_path=*/NULL_TREE
,
4402 /*access_path=*/NULL_TREE
,
4404 candidates
, complain
);
4406 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4408 cand
= tourney (*candidates
, complain
);
4412 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4416 /* Print an error message about being unable to build a call to FN with
4417 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4418 be located; CANDIDATES is a possibly empty list of such
4422 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4423 struct z_candidate
*candidates
)
4425 tree targs
= NULL_TREE
;
4426 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4428 targs
= TREE_OPERAND (fn
, 1);
4429 fn
= TREE_OPERAND (fn
, 0);
4431 tree name
= OVL_NAME (fn
);
4432 location_t loc
= location_of (name
);
4434 name
= lookup_template_function (name
, targs
);
4436 auto_diagnostic_group d
;
4437 if (!any_strictly_viable (candidates
))
4438 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4439 name
, build_tree_list_vec (args
));
4441 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4442 name
, build_tree_list_vec (args
));
4444 print_z_candidates (loc
, candidates
);
4447 /* Return an expression for a call to FN (a namespace-scope function,
4448 or a static member function) with the ARGS. This may change
4452 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4453 tsubst_flags_t complain
)
4455 struct z_candidate
*candidates
, *cand
;
4460 if (args
!= NULL
&& *args
!= NULL
)
4462 *args
= resolve_args (*args
, complain
);
4464 return error_mark_node
;
4468 tm_malloc_replacement (fn
);
4470 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4471 p
= conversion_obstack_alloc (0);
4473 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4478 if (complain
& tf_error
)
4480 // If there is a single (non-viable) function candidate,
4481 // let the error be diagnosed by cp_build_function_call_vec.
4482 if (!any_viable_p
&& candidates
&& ! candidates
->next
4483 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4484 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4486 // Otherwise, emit notes for non-viable candidates.
4487 print_error_for_call_failure (fn
, *args
, candidates
);
4489 result
= error_mark_node
;
4493 int flags
= LOOKUP_NORMAL
;
4494 /* If fn is template_id_expr, the call has explicit template arguments
4495 (e.g. func<int>(5)), communicate this info to build_over_call
4496 through flags so that later we can use it to decide whether to warn
4497 about peculiar null pointer conversion. */
4498 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4500 /* If overload resolution selects a specialization of a
4501 function concept for non-dependent template arguments,
4502 the expression is true if the constraints are satisfied
4503 and false otherwise.
4505 NOTE: This is an extension of Concepts Lite TS that
4506 allows constraints to be used in expressions. */
4507 if (flag_concepts
&& !processing_template_decl
)
4509 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4510 tree targs
= DECL_TI_ARGS (cand
->fn
);
4511 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4512 if (DECL_DECLARED_CONCEPT_P (decl
))
4513 return evaluate_function_concept (decl
, targs
);
4516 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4519 result
= build_over_call (cand
, flags
, complain
);
4522 /* Free all the conversions we allocated. */
4523 obstack_free (&conversion_obstack
, p
);
4528 /* Build a call to a global operator new. FNNAME is the name of the
4529 operator (either "operator new" or "operator new[]") and ARGS are
4530 the arguments provided. This may change ARGS. *SIZE points to the
4531 total number of bytes required by the allocation, and is updated if
4532 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4533 be used. If this function determines that no cookie should be
4534 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4535 is not NULL_TREE, it is evaluated before calculating the final
4536 array size, and if it fails, the array size is replaced with
4537 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4538 is non-NULL, it will be set, upon return, to the allocation
4542 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4543 tree
*size
, tree
*cookie_size
,
4544 tree align_arg
, tree size_check
,
4545 tree
*fn
, tsubst_flags_t complain
)
4547 tree original_size
= *size
;
4549 struct z_candidate
*candidates
;
4550 struct z_candidate
*cand
= NULL
;
4555 /* Set to (size_t)-1 if the size check fails. */
4556 if (size_check
!= NULL_TREE
)
4558 tree errval
= TYPE_MAX_VALUE (sizetype
);
4559 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4560 errval
= throw_bad_array_new_length ();
4561 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4562 original_size
, errval
);
4564 vec_safe_insert (*args
, 0, *size
);
4565 *args
= resolve_args (*args
, complain
);
4567 return error_mark_node
;
4573 If this lookup fails to find the name, or if the allocated type
4574 is not a class type, the allocation function's name is looked
4575 up in the global scope.
4577 we disregard block-scope declarations of "operator new". */
4578 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4579 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4583 vec
<tree
, va_gc
>* align_args
4584 = vec_copy_and_insert (*args
, align_arg
, 1);
4585 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4586 &any_viable_p
, tf_none
);
4589 /* If no aligned allocation function matches, try again without the
4593 /* Figure out what function is being called. */
4595 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4598 /* If no suitable function could be found, issue an error message
4602 if (complain
& tf_error
)
4603 print_error_for_call_failure (fns
, *args
, candidates
);
4604 return error_mark_node
;
4607 /* If a cookie is required, add some extra space. Whether
4608 or not a cookie is required cannot be determined until
4609 after we know which function was called. */
4612 bool use_cookie
= true;
4615 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4616 /* Skip the size_t parameter. */
4617 arg_types
= TREE_CHAIN (arg_types
);
4618 /* Check the remaining parameters (if any). */
4620 && TREE_CHAIN (arg_types
) == void_list_node
4621 && same_type_p (TREE_VALUE (arg_types
),
4624 /* If we need a cookie, adjust the number of bytes allocated. */
4627 /* Update the total size. */
4628 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4631 /* Set to (size_t)-1 if the size check fails. */
4632 gcc_assert (size_check
!= NULL_TREE
);
4633 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4634 *size
, TYPE_MAX_VALUE (sizetype
));
4636 /* Update the argument list to reflect the adjusted size. */
4637 (**args
)[0] = *size
;
4640 *cookie_size
= NULL_TREE
;
4643 /* Tell our caller which function we decided to call. */
4647 /* Build the CALL_EXPR. */
4648 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4651 /* Build a new call to operator(). This may change ARGS. */
4654 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4656 struct z_candidate
*candidates
= 0, *cand
;
4657 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4659 tree result
= NULL_TREE
;
4662 obj
= mark_lvalue_use (obj
);
4664 if (error_operand_p (obj
))
4665 return error_mark_node
;
4667 tree type
= TREE_TYPE (obj
);
4669 obj
= prep_operand (obj
);
4671 if (TYPE_PTRMEMFUNC_P (type
))
4673 if (complain
& tf_error
)
4674 /* It's no good looking for an overloaded operator() on a
4675 pointer-to-member-function. */
4676 error ("pointer-to-member function %qE cannot be called without "
4677 "an object; consider using %<.*%> or %<->*%>", obj
);
4678 return error_mark_node
;
4681 if (TYPE_BINFO (type
))
4683 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4684 if (fns
== error_mark_node
)
4685 return error_mark_node
;
4690 if (args
!= NULL
&& *args
!= NULL
)
4692 *args
= resolve_args (*args
, complain
);
4694 return error_mark_node
;
4697 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4698 p
= conversion_obstack_alloc (0);
4702 first_mem_arg
= obj
;
4704 add_candidates (BASELINK_FUNCTIONS (fns
),
4705 first_mem_arg
, *args
, NULL_TREE
,
4707 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4708 LOOKUP_NORMAL
, &candidates
, complain
);
4711 convs
= lookup_conversions (type
);
4713 for (; convs
; convs
= TREE_CHAIN (convs
))
4715 tree totype
= TREE_TYPE (convs
);
4717 if (TYPE_PTRFN_P (totype
)
4718 || TYPE_REFFN_P (totype
)
4719 || (TYPE_REF_P (totype
)
4720 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4721 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4725 if (DECL_NONCONVERTING_P (fn
))
4728 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4729 add_template_conv_candidate
4730 (&candidates
, fn
, obj
, *args
, totype
,
4731 /*access_path=*/NULL_TREE
,
4732 /*conversion_path=*/NULL_TREE
, complain
);
4734 add_conv_candidate (&candidates
, fn
, obj
,
4735 *args
, /*conversion_path=*/NULL_TREE
,
4736 /*access_path=*/NULL_TREE
, complain
);
4740 /* Be strict here because if we choose a bad conversion candidate, the
4741 errors we get won't mention the call context. */
4742 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4745 if (complain
& tf_error
)
4747 auto_diagnostic_group d
;
4748 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4749 build_tree_list_vec (*args
));
4750 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4752 result
= error_mark_node
;
4756 cand
= tourney (candidates
, complain
);
4759 if (complain
& tf_error
)
4761 auto_diagnostic_group d
;
4762 error ("call of %<(%T) (%A)%> is ambiguous",
4763 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4764 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4766 result
= error_mark_node
;
4768 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4769 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4770 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4771 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4774 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4775 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4779 gcc_checking_assert (TYPE_P (cand
->fn
));
4780 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4782 obj
= convert_from_reference (obj
);
4783 result
= cp_build_function_call_vec (obj
, args
, complain
);
4787 /* Free all the conversions we allocated. */
4788 obstack_free (&conversion_obstack
, p
);
4793 /* Wrapper for above. */
4796 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4799 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4800 ret
= build_op_call_1 (obj
, args
, complain
);
4801 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4805 /* Called by op_error to prepare format strings suitable for the error
4806 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4807 and a suffix (controlled by NTYPES). */
4810 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4814 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4815 : G_("no match for "), errmsg
, NULL
);
4818 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4819 else if (ntypes
== 2)
4820 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4822 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4828 op_error (const op_location_t
&loc
,
4829 enum tree_code code
, enum tree_code code2
,
4830 tree arg1
, tree arg2
, tree arg3
, bool match
)
4832 bool assop
= code
== MODIFY_EXPR
;
4833 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4838 if (flag_diagnostics_show_caret
)
4839 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4841 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4843 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4844 "in %<%E ? %E : %E%>"), 3, match
),
4846 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4849 case POSTINCREMENT_EXPR
:
4850 case POSTDECREMENT_EXPR
:
4851 if (flag_diagnostics_show_caret
)
4852 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4853 opname
, TREE_TYPE (arg1
));
4855 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4857 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4861 if (flag_diagnostics_show_caret
)
4862 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4863 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4865 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4867 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4872 if (flag_diagnostics_show_caret
)
4873 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4874 opname
, TREE_TYPE (arg1
));
4876 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4877 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4882 if (flag_diagnostics_show_caret
)
4884 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4886 op_error_string (G_("%<operator%s%>"), 2, match
),
4887 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4890 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4892 opname
, arg1
, opname
, arg2
,
4893 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4895 if (flag_diagnostics_show_caret
)
4896 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4897 opname
, TREE_TYPE (arg1
));
4899 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4901 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4906 /* Return the implicit conversion sequence that could be used to
4907 convert E1 to E2 in [expr.cond]. */
4910 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4912 tree t1
= non_reference (TREE_TYPE (e1
));
4913 tree t2
= non_reference (TREE_TYPE (e2
));
4919 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4920 implicitly converted (clause _conv_) to the type "lvalue reference to
4921 T2", subject to the constraint that in the conversion the
4922 reference must bind directly (_dcl.init.ref_) to an lvalue.
4924 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4925 implicitly converted to the type "rvalue reference to T2", subject to
4926 the constraint that the reference must bind directly. */
4929 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4930 conv
= implicit_conversion (rtype
,
4934 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4935 |LOOKUP_ONLYCONVERTING
,
4937 if (conv
&& !conv
->bad_p
)
4941 /* If E2 is a prvalue or if neither of the conversions above can be done
4942 and at least one of the operands has (possibly cv-qualified) class
4944 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4949 If E1 and E2 have class type, and the underlying class types are
4950 the same or one is a base class of the other: E1 can be converted
4951 to match E2 if the class of T2 is the same type as, or a base
4952 class of, the class of T1, and the cv-qualification of T2 is the
4953 same cv-qualification as, or a greater cv-qualification than, the
4954 cv-qualification of T1. If the conversion is applied, E1 is
4955 changed to an rvalue of type T2 that still refers to the original
4956 source class object (or the appropriate subobject thereof). */
4957 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4958 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4960 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4962 conv
= build_identity_conv (t1
, e1
);
4963 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4964 TYPE_MAIN_VARIANT (t2
)))
4965 conv
= build_conv (ck_base
, t2
, conv
);
4967 conv
= build_conv (ck_rvalue
, t2
, conv
);
4976 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4977 converted to the type that expression E2 would have if E2 were
4978 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4979 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4980 LOOKUP_IMPLICIT
, complain
);
4983 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4984 arguments to the conditional expression. */
4987 build_conditional_expr_1 (const op_location_t
&loc
,
4988 tree arg1
, tree arg2
, tree arg3
,
4989 tsubst_flags_t complain
)
4993 tree result
= NULL_TREE
;
4994 tree result_type
= NULL_TREE
;
4995 bool is_glvalue
= true;
4996 struct z_candidate
*candidates
= 0;
4997 struct z_candidate
*cand
;
4999 tree orig_arg2
, orig_arg3
;
5001 /* As a G++ extension, the second argument to the conditional can be
5002 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
5003 c'.) If the second operand is omitted, make sure it is
5004 calculated only once. */
5007 if (complain
& tf_error
)
5008 pedwarn (loc
, OPT_Wpedantic
,
5009 "ISO C++ forbids omitting the middle term of a ?: expression");
5011 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
5012 warn_for_omitted_condop (loc
, arg1
);
5014 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
5015 if (lvalue_p (arg1
))
5016 arg2
= arg1
= cp_stabilize_reference (arg1
);
5018 arg2
= arg1
= cp_save_expr (arg1
);
5021 /* If something has already gone wrong, just pass that fact up the
5023 if (error_operand_p (arg1
)
5024 || error_operand_p (arg2
)
5025 || error_operand_p (arg3
))
5026 return error_mark_node
;
5031 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
5033 tree arg1_type
= TREE_TYPE (arg1
);
5035 /* If arg1 is another cond_expr choosing between -1 and 0,
5036 then we can use its comparison. It may help to avoid
5037 additional comparison, produce more accurate diagnostics
5038 and enables folding. */
5039 if (TREE_CODE (arg1
) == VEC_COND_EXPR
5040 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
5041 && integer_zerop (TREE_OPERAND (arg1
, 2)))
5042 arg1
= TREE_OPERAND (arg1
, 0);
5044 arg1
= force_rvalue (arg1
, complain
);
5045 arg2
= force_rvalue (arg2
, complain
);
5046 arg3
= force_rvalue (arg3
, complain
);
5048 /* force_rvalue can return error_mark on valid arguments. */
5049 if (error_operand_p (arg1
)
5050 || error_operand_p (arg2
)
5051 || error_operand_p (arg3
))
5052 return error_mark_node
;
5054 arg2_type
= TREE_TYPE (arg2
);
5055 arg3_type
= TREE_TYPE (arg3
);
5057 if (!VECTOR_TYPE_P (arg2_type
)
5058 && !VECTOR_TYPE_P (arg3_type
))
5060 /* Rely on the error messages of the scalar version. */
5061 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
5062 orig_arg2
, orig_arg3
, complain
);
5063 if (scal
== error_mark_node
)
5064 return error_mark_node
;
5065 tree stype
= TREE_TYPE (scal
);
5066 tree ctype
= TREE_TYPE (arg1_type
);
5067 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
5068 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
5070 if (complain
& tf_error
)
5071 error_at (loc
, "inferred scalar type %qT is not an integer or "
5072 "floating point type of the same size as %qT", stype
,
5073 COMPARISON_CLASS_P (arg1
)
5074 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
5076 return error_mark_node
;
5079 tree vtype
= build_opaque_vector_type (stype
,
5080 TYPE_VECTOR_SUBPARTS (arg1_type
));
5081 /* We could pass complain & tf_warning to unsafe_conversion_p,
5082 but the warnings (like Wsign-conversion) have already been
5083 given by the scalar build_conditional_expr_1. We still check
5084 unsafe_conversion_p to forbid truncating long long -> float. */
5085 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
5087 if (complain
& tf_error
)
5088 error_at (loc
, "conversion of scalar %qH to vector %qI "
5089 "involves truncation", arg2_type
, vtype
);
5090 return error_mark_node
;
5092 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
5094 if (complain
& tf_error
)
5095 error_at (loc
, "conversion of scalar %qH to vector %qI "
5096 "involves truncation", arg3_type
, vtype
);
5097 return error_mark_node
;
5100 arg2
= cp_convert (stype
, arg2
, complain
);
5101 arg2
= save_expr (arg2
);
5102 arg2
= build_vector_from_val (vtype
, arg2
);
5104 arg3
= cp_convert (stype
, arg3
, complain
);
5105 arg3
= save_expr (arg3
);
5106 arg3
= build_vector_from_val (vtype
, arg3
);
5110 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5112 enum stv_conv convert_flag
=
5113 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5114 complain
& tf_error
);
5116 switch (convert_flag
)
5119 return error_mark_node
;
5122 arg2
= save_expr (arg2
);
5123 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5124 arg2
= build_vector_from_val (arg3_type
, arg2
);
5125 arg2_type
= TREE_TYPE (arg2
);
5130 arg3
= save_expr (arg3
);
5131 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5132 arg3
= build_vector_from_val (arg2_type
, arg3
);
5133 arg3_type
= TREE_TYPE (arg3
);
5141 if (!same_type_p (arg2_type
, arg3_type
)
5142 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5143 TYPE_VECTOR_SUBPARTS (arg2_type
))
5144 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5146 if (complain
& tf_error
)
5148 "incompatible vector types in conditional expression: "
5149 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5150 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5151 return error_mark_node
;
5154 if (!COMPARISON_CLASS_P (arg1
))
5156 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5157 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5159 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5164 The first expression is implicitly converted to bool (clause
5166 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5168 if (error_operand_p (arg1
))
5169 return error_mark_node
;
5173 If either the second or the third operand has type (possibly
5174 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5175 array-to-pointer (_conv.array_), and function-to-pointer
5176 (_conv.func_) standard conversions are performed on the second
5177 and third operands. */
5178 arg2_type
= unlowered_expr_type (arg2
);
5179 arg3_type
= unlowered_expr_type (arg3
);
5180 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5182 /* 'void' won't help in resolving an overloaded expression on the
5183 other side, so require it to resolve by itself. */
5184 if (arg2_type
== unknown_type_node
)
5186 arg2
= resolve_nondeduced_context_or_error (arg2
, complain
);
5187 arg2_type
= TREE_TYPE (arg2
);
5189 if (arg3_type
== unknown_type_node
)
5191 arg3
= resolve_nondeduced_context_or_error (arg3
, complain
);
5192 arg3_type
= TREE_TYPE (arg3
);
5197 One of the following shall hold:
5199 --The second or the third operand (but not both) is a
5200 throw-expression (_except.throw_); the result is of the type
5201 and value category of the other.
5203 --Both the second and the third operands have type void; the
5204 result is of type void and is a prvalue. */
5205 if (TREE_CODE (arg2
) == THROW_EXPR
5206 && TREE_CODE (arg3
) != THROW_EXPR
)
5208 result_type
= arg3_type
;
5209 is_glvalue
= glvalue_p (arg3
);
5211 else if (TREE_CODE (arg2
) != THROW_EXPR
5212 && TREE_CODE (arg3
) == THROW_EXPR
)
5214 result_type
= arg2_type
;
5215 is_glvalue
= glvalue_p (arg2
);
5217 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5219 result_type
= void_type_node
;
5224 if (complain
& tf_error
)
5226 if (VOID_TYPE_P (arg2_type
))
5227 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5228 "second operand to the conditional operator "
5229 "is of type %<void%>, but the third operand is "
5230 "neither a throw-expression nor of type %<void%>");
5232 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5233 "third operand to the conditional operator "
5234 "is of type %<void%>, but the second operand is "
5235 "neither a throw-expression nor of type %<void%>");
5237 return error_mark_node
;
5240 goto valid_operands
;
5244 Otherwise, if the second and third operand have different types,
5245 and either has (possibly cv-qualified) class type, or if both are
5246 glvalues of the same value category and the same type except for
5247 cv-qualification, an attempt is made to convert each of those operands
5248 to the type of the other. */
5249 else if (!same_type_p (arg2_type
, arg3_type
)
5250 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5251 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5253 && glvalue_p (arg2
) && glvalue_p (arg3
)
5254 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5258 bool converted
= false;
5260 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5261 p
= conversion_obstack_alloc (0);
5263 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5264 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5268 If both can be converted, or one can be converted but the
5269 conversion is ambiguous, the program is ill-formed. If
5270 neither can be converted, the operands are left unchanged and
5271 further checking is performed as described below. If exactly
5272 one conversion is possible, that conversion is applied to the
5273 chosen operand and the converted operand is used in place of
5274 the original operand for the remainder of this section. */
5275 if ((conv2
&& !conv2
->bad_p
5276 && conv3
&& !conv3
->bad_p
)
5277 || (conv2
&& conv2
->kind
== ck_ambig
)
5278 || (conv3
&& conv3
->kind
== ck_ambig
))
5280 if (complain
& tf_error
)
5282 error_at (loc
, "operands to ?: have different types %qT and %qT",
5283 arg2_type
, arg3_type
);
5284 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5285 inform (loc
, " and each type can be converted to the other");
5286 else if (conv2
&& conv2
->kind
== ck_ambig
)
5287 convert_like (conv2
, arg2
, complain
);
5289 convert_like (conv3
, arg3
, complain
);
5291 result
= error_mark_node
;
5293 else if (conv2
&& !conv2
->bad_p
)
5295 arg2
= convert_like (conv2
, arg2
, complain
);
5296 arg2
= convert_from_reference (arg2
);
5297 arg2_type
= TREE_TYPE (arg2
);
5298 /* Even if CONV2 is a valid conversion, the result of the
5299 conversion may be invalid. For example, if ARG3 has type
5300 "volatile X", and X does not have a copy constructor
5301 accepting a "volatile X&", then even if ARG2 can be
5302 converted to X, the conversion will fail. */
5303 if (error_operand_p (arg2
))
5304 result
= error_mark_node
;
5307 else if (conv3
&& !conv3
->bad_p
)
5309 arg3
= convert_like (conv3
, arg3
, complain
);
5310 arg3
= convert_from_reference (arg3
);
5311 arg3_type
= TREE_TYPE (arg3
);
5312 if (error_operand_p (arg3
))
5313 result
= error_mark_node
;
5317 /* Free all the conversions we allocated. */
5318 obstack_free (&conversion_obstack
, p
);
5323 /* If, after the conversion, both operands have class type,
5324 treat the cv-qualification of both operands as if it were the
5325 union of the cv-qualification of the operands.
5327 The standard is not clear about what to do in this
5328 circumstance. For example, if the first operand has type
5329 "const X" and the second operand has a user-defined
5330 conversion to "volatile X", what is the type of the second
5331 operand after this step? Making it be "const X" (matching
5332 the first operand) seems wrong, as that discards the
5333 qualification without actually performing a copy. Leaving it
5334 as "volatile X" seems wrong as that will result in the
5335 conditional expression failing altogether, even though,
5336 according to this step, the one operand could be converted to
5337 the type of the other. */
5339 && CLASS_TYPE_P (arg2_type
)
5340 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5341 arg2_type
= arg3_type
=
5342 cp_build_qualified_type (arg2_type
,
5343 cp_type_quals (arg2_type
)
5344 | cp_type_quals (arg3_type
));
5349 If the second and third operands are glvalues of the same value
5350 category and have the same type, the result is of that type and
5352 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5353 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5354 && same_type_p (arg2_type
, arg3_type
))
5356 result_type
= arg2_type
;
5357 arg2
= mark_lvalue_use (arg2
);
5358 arg3
= mark_lvalue_use (arg3
);
5359 goto valid_operands
;
5364 Otherwise, the result is an rvalue. If the second and third
5365 operand do not have the same type, and either has (possibly
5366 cv-qualified) class type, overload resolution is used to
5367 determine the conversions (if any) to be applied to the operands
5368 (_over.match.oper_, _over.built_). */
5370 if (!same_type_p (arg2_type
, arg3_type
)
5371 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5377 /* Rearrange the arguments so that add_builtin_candidate only has
5378 to know about two args. In build_builtin_candidate, the
5379 arguments are unscrambled. */
5383 add_builtin_candidates (&candidates
,
5386 ovl_op_identifier (false, COND_EXPR
),
5388 LOOKUP_NORMAL
, complain
);
5392 If the overload resolution fails, the program is
5394 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5397 if (complain
& tf_error
)
5398 error_at (loc
, "operands to ?: have different types %qT and %qT",
5399 arg2_type
, arg3_type
);
5400 return error_mark_node
;
5402 cand
= tourney (candidates
, complain
);
5405 if (complain
& tf_error
)
5407 auto_diagnostic_group d
;
5408 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5409 print_z_candidates (loc
, candidates
);
5411 return error_mark_node
;
5416 Otherwise, the conversions thus determined are applied, and
5417 the converted operands are used in place of the original
5418 operands for the remainder of this section. */
5419 conv
= cand
->convs
[0];
5420 arg1
= convert_like (conv
, arg1
, complain
);
5421 conv
= cand
->convs
[1];
5422 arg2
= convert_like (conv
, arg2
, complain
);
5423 arg2_type
= TREE_TYPE (arg2
);
5424 conv
= cand
->convs
[2];
5425 arg3
= convert_like (conv
, arg3
, complain
);
5426 arg3_type
= TREE_TYPE (arg3
);
5431 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5432 and function-to-pointer (_conv.func_) standard conversions are
5433 performed on the second and third operands.
5435 We need to force the lvalue-to-rvalue conversion here for class types,
5436 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5437 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5440 arg2
= force_rvalue (arg2
, complain
);
5441 if (!CLASS_TYPE_P (arg2_type
))
5442 arg2_type
= TREE_TYPE (arg2
);
5444 arg3
= force_rvalue (arg3
, complain
);
5445 if (!CLASS_TYPE_P (arg3_type
))
5446 arg3_type
= TREE_TYPE (arg3
);
5448 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5449 return error_mark_node
;
5453 After those conversions, one of the following shall hold:
5455 --The second and third operands have the same type; the result is of
5457 if (same_type_p (arg2_type
, arg3_type
))
5458 result_type
= arg2_type
;
5461 --The second and third operands have arithmetic or enumeration
5462 type; the usual arithmetic conversions are performed to bring
5463 them to a common type, and the result is of that type. */
5464 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5465 || UNSCOPED_ENUM_P (arg2_type
))
5466 && (ARITHMETIC_TYPE_P (arg3_type
)
5467 || UNSCOPED_ENUM_P (arg3_type
)))
5469 /* In this case, there is always a common type. */
5470 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5472 if (complain
& tf_warning
)
5473 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5474 "implicit conversion from %qH to %qI to "
5475 "match other result of conditional",
5478 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5479 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5481 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5482 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5483 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5484 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5485 && (DECL_CONTEXT (stripped_orig_arg2
)
5486 == DECL_CONTEXT (stripped_orig_arg3
)))
5487 /* Two enumerators from the same enumeration can have different
5488 types when the enumeration is still being defined. */;
5489 else if (complain
& tf_warning
)
5490 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5491 "conditional expression: %qT vs %qT",
5492 arg2_type
, arg3_type
);
5494 else if (extra_warnings
5495 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5496 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5497 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5498 && !same_type_p (arg2_type
,
5499 type_promotes_to (arg3_type
)))))
5501 if (complain
& tf_warning
)
5502 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5503 "conditional expression");
5506 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5507 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5511 --The second and third operands have pointer type, or one has
5512 pointer type and the other is a null pointer constant; pointer
5513 conversions (_conv.ptr_) and qualification conversions
5514 (_conv.qual_) are performed to bring them to their composite
5515 pointer type (_expr.rel_). The result is of the composite
5518 --The second and third operands have pointer to member type, or
5519 one has pointer to member type and the other is a null pointer
5520 constant; pointer to member conversions (_conv.mem_) and
5521 qualification conversions (_conv.qual_) are performed to bring
5522 them to a common type, whose cv-qualification shall match the
5523 cv-qualification of either the second or the third operand.
5524 The result is of the common type. */
5525 else if ((null_ptr_cst_p (arg2
)
5526 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5527 || (null_ptr_cst_p (arg3
)
5528 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5529 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5530 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5531 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5533 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5534 arg3
, CPO_CONDITIONAL_EXPR
,
5536 if (result_type
== error_mark_node
)
5537 return error_mark_node
;
5538 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5539 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5544 if (complain
& tf_error
)
5545 error_at (loc
, "operands to ?: have different types %qT and %qT",
5546 arg2_type
, arg3_type
);
5547 return error_mark_node
;
5550 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5551 return error_mark_node
;
5554 if (processing_template_decl
&& is_glvalue
)
5556 /* Let lvalue_kind know this was a glvalue. */
5557 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5558 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5561 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5563 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5564 warn here, because the COND_EXPR will be turned into ARG2. */
5565 if (warn_duplicated_branches
5566 && (complain
& tf_warning
)
5567 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5568 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5569 "this condition has identical branches");
5571 /* We can't use result_type below, as fold might have returned a
5576 /* Expand both sides into the same slot, hopefully the target of
5577 the ?: expression. We used to check for TARGET_EXPRs here,
5578 but now we sometimes wrap them in NOP_EXPRs so the test would
5580 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5581 result
= get_target_expr_sfinae (result
, complain
);
5582 /* If this expression is an rvalue, but might be mistaken for an
5583 lvalue, we must add a NON_LVALUE_EXPR. */
5584 result
= rvalue (result
);
5587 result
= force_paren_expr (result
);
5592 /* Wrapper for above. */
5595 build_conditional_expr (const op_location_t
&loc
,
5596 tree arg1
, tree arg2
, tree arg3
,
5597 tsubst_flags_t complain
)
5600 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5601 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5602 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5606 /* OPERAND is an operand to an expression. Perform necessary steps
5607 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5611 prep_operand (tree operand
)
5615 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5616 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5617 /* Make sure the template type is instantiated now. */
5618 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5624 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5625 OVERLOAD) to the CANDIDATES, returning an updated list of
5626 CANDIDATES. The ARGS are the arguments provided to the call;
5627 if FIRST_ARG is non-null it is the implicit object argument,
5628 otherwise the first element of ARGS is used if needed. The
5629 EXPLICIT_TARGS are explicit template arguments provided.
5630 TEMPLATE_ONLY is true if only template functions should be
5631 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5632 add_function_candidate. */
5635 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5637 tree explicit_targs
, bool template_only
,
5638 tree conversion_path
, tree access_path
,
5640 struct z_candidate
**candidates
,
5641 tsubst_flags_t complain
)
5644 const vec
<tree
, va_gc
> *non_static_args
;
5645 bool check_list_ctor
= false;
5646 bool check_converting
= false;
5647 unification_kind_t strict
;
5652 /* Precalculate special handling of constructors and conversion ops. */
5653 tree fn
= OVL_FIRST (fns
);
5654 if (DECL_CONV_FN_P (fn
))
5656 check_list_ctor
= false;
5657 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5658 if (flags
& LOOKUP_NO_CONVERSION
)
5659 /* We're doing return_type(x). */
5660 strict
= DEDUCE_CONV
;
5662 /* We're doing x.operator return_type(). */
5663 strict
= DEDUCE_EXACT
;
5664 /* [over.match.funcs] For conversion functions, the function
5665 is considered to be a member of the class of the implicit
5666 object argument for the purpose of defining the type of
5667 the implicit object parameter. */
5668 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5672 if (DECL_CONSTRUCTOR_P (fn
))
5674 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5675 /* For list-initialization we consider explicit constructors
5676 and complain if one is chosen. */
5678 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5679 == LOOKUP_ONLYCONVERTING
);
5681 strict
= DEDUCE_CALL
;
5682 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5686 non_static_args
= args
;
5688 /* Delay creating the implicit this parameter until it is needed. */
5689 non_static_args
= NULL
;
5691 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5695 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5697 if (check_list_ctor
&& !is_list_ctor (fn
))
5700 tree fn_first_arg
= NULL_TREE
;
5701 const vec
<tree
, va_gc
> *fn_args
= args
;
5703 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5705 /* Figure out where the object arg comes from. If this
5706 function is a non-static member and we didn't get an
5707 implicit object argument, move it out of args. */
5708 if (first_arg
== NULL_TREE
)
5712 vec
<tree
, va_gc
> *tempvec
;
5713 vec_alloc (tempvec
, args
->length () - 1);
5714 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5715 tempvec
->quick_push (arg
);
5716 non_static_args
= tempvec
;
5717 first_arg
= (*args
)[0];
5720 fn_first_arg
= first_arg
;
5721 fn_args
= non_static_args
;
5724 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5725 add_template_candidate (candidates
,
5737 else if (!template_only
)
5738 add_function_candidate (candidates
,
5751 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5752 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5755 op_is_ordered (tree_code code
)
5761 return (flag_strong_eval_order
> 1 ? -1 : 0);
5765 return (flag_strong_eval_order
> 1 ? 1 : 0);
5768 // Not overloadable (yet).
5770 // Only one argument.
5777 return (flag_strong_eval_order
? 1 : 0);
5785 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5786 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5787 tsubst_flags_t complain
)
5789 struct z_candidate
*candidates
= 0, *cand
;
5790 vec
<tree
, va_gc
> *arglist
;
5792 tree result
= NULL_TREE
;
5793 bool result_valid_p
= false;
5794 enum tree_code code2
= NOP_EXPR
;
5795 enum tree_code code_orig_arg1
= ERROR_MARK
;
5796 enum tree_code code_orig_arg2
= ERROR_MARK
;
5802 if (error_operand_p (arg1
)
5803 || error_operand_p (arg2
)
5804 || error_operand_p (arg3
))
5805 return error_mark_node
;
5807 bool ismodop
= code
== MODIFY_EXPR
;
5810 code2
= TREE_CODE (arg3
);
5813 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5815 arg1
= prep_operand (arg1
);
5817 bool memonly
= false;
5822 case VEC_DELETE_EXPR
:
5824 /* Use build_op_new_call and build_op_delete_call instead. */
5828 /* Use build_op_call instead. */
5831 case TRUTH_ORIF_EXPR
:
5832 case TRUTH_ANDIF_EXPR
:
5833 case TRUTH_AND_EXPR
:
5835 /* These are saved for the sake of warn_logical_operator. */
5836 code_orig_arg1
= TREE_CODE (arg1
);
5837 code_orig_arg2
= TREE_CODE (arg2
);
5845 /* These are saved for the sake of maybe_warn_bool_compare. */
5846 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5847 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5850 /* =, ->, [], () must be non-static member functions. */
5852 if (code2
!= NOP_EXPR
)
5864 arg2
= prep_operand (arg2
);
5865 arg3
= prep_operand (arg3
);
5867 if (code
== COND_EXPR
)
5868 /* Use build_conditional_expr instead. */
5870 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5871 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5874 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5875 arg2
= integer_zero_node
;
5877 vec_alloc (arglist
, 3);
5878 arglist
->quick_push (arg1
);
5879 if (arg2
!= NULL_TREE
)
5880 arglist
->quick_push (arg2
);
5881 if (arg3
!= NULL_TREE
)
5882 arglist
->quick_push (arg3
);
5884 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5885 p
= conversion_obstack_alloc (0);
5887 /* Add namespace-scope operators to the list of functions to
5891 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5892 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5893 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5894 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5895 flags
, &candidates
, complain
);
5900 args
[2] = NULL_TREE
;
5902 /* Add class-member operators to the candidate set. */
5903 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5907 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5908 if (fns
== error_mark_node
)
5910 result
= error_mark_node
;
5911 goto user_defined_result_ready
;
5914 add_candidates (BASELINK_FUNCTIONS (fns
),
5915 NULL_TREE
, arglist
, NULL_TREE
,
5917 BASELINK_BINFO (fns
),
5918 BASELINK_ACCESS_BINFO (fns
),
5919 flags
, &candidates
, complain
);
5921 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5922 only non-member functions that have type T1 or reference to
5923 cv-qualified-opt T1 for the first argument, if the first argument
5924 has an enumeration type, or T2 or reference to cv-qualified-opt
5925 T2 for the second argument, if the second argument has an
5926 enumeration type. Filter out those that don't match. */
5927 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5929 struct z_candidate
**candp
, **next
;
5931 for (candp
= &candidates
; *candp
; candp
= next
)
5933 tree parmlist
, parmtype
;
5934 int i
, nargs
= (arg2
? 2 : 1);
5939 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5941 for (i
= 0; i
< nargs
; ++i
)
5943 parmtype
= TREE_VALUE (parmlist
);
5945 if (TYPE_REF_P (parmtype
))
5946 parmtype
= TREE_TYPE (parmtype
);
5947 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5948 && (same_type_ignoring_top_level_qualifiers_p
5949 (TREE_TYPE (args
[i
]), parmtype
)))
5952 parmlist
= TREE_CHAIN (parmlist
);
5955 /* No argument has an appropriate type, so remove this
5956 candidate function from the list. */
5959 *candp
= cand
->next
;
5965 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5972 /* For these, the built-in candidates set is empty
5973 [over.match.oper]/3. We don't want non-strict matches
5974 because exact matches are always possible with built-in
5975 operators. The built-in candidate set for COMPONENT_REF
5976 would be empty too, but since there are no such built-in
5977 operators, we accept non-strict matches for them. */
5986 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5991 case POSTINCREMENT_EXPR
:
5992 case POSTDECREMENT_EXPR
:
5993 /* Don't try anything fancy if we're not allowed to produce
5995 if (!(complain
& tf_error
))
5996 return error_mark_node
;
5998 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5999 distinguish between prefix and postfix ++ and
6000 operator++() was used for both, so we allow this with
6004 const char *msg
= (flag_permissive
)
6005 ? G_("no %<%D(int)%> declared for postfix %qs,"
6006 " trying prefix operator instead")
6007 : G_("no %<%D(int)%> declared for postfix %qs");
6008 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
6011 if (!flag_permissive
)
6012 return error_mark_node
;
6014 if (code
== POSTINCREMENT_EXPR
)
6015 code
= PREINCREMENT_EXPR
;
6017 code
= PREDECREMENT_EXPR
;
6018 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
6019 NULL_TREE
, overload
, complain
);
6022 /* The caller will deal with these. */
6027 result_valid_p
= true;
6031 if (complain
& tf_error
)
6033 /* If one of the arguments of the operator represents
6034 an invalid use of member function pointer, try to report
6035 a meaningful error ... */
6036 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
6037 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
6038 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
6039 /* We displayed the error message. */;
6042 /* ... Otherwise, report the more generic
6043 "no matching operator found" error */
6044 auto_diagnostic_group d
;
6045 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
6046 print_z_candidates (loc
, candidates
);
6049 result
= error_mark_node
;
6055 cand
= tourney (candidates
, complain
);
6058 if (complain
& tf_error
)
6060 auto_diagnostic_group d
;
6061 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
6062 print_z_candidates (loc
, candidates
);
6064 result
= error_mark_node
;
6066 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
6069 *overload
= cand
->fn
;
6071 if (resolve_args (arglist
, complain
) == NULL
)
6072 result
= error_mark_node
;
6074 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6076 if (trivial_fn_p (cand
->fn
))
6077 /* There won't be a CALL_EXPR. */;
6078 else if (result
&& result
!= error_mark_node
)
6080 tree call
= extract_call_expr (result
);
6081 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
6083 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
6084 /* This prevents build_new_function_call from discarding this
6085 function during instantiation of the enclosing template. */
6086 KOENIG_LOOKUP_P (call
) = 1;
6088 /* Specify evaluation order as per P0145R2. */
6089 CALL_EXPR_ORDERED_ARGS (call
) = false;
6090 switch (op_is_ordered (code
))
6093 CALL_EXPR_REVERSE_ARGS (call
) = true;
6097 CALL_EXPR_ORDERED_ARGS (call
) = true;
6107 /* Give any warnings we noticed during overload resolution. */
6108 if (cand
->warnings
&& (complain
& tf_warning
))
6110 struct candidate_warning
*w
;
6111 for (w
= cand
->warnings
; w
; w
= w
->next
)
6112 joust (cand
, w
->loser
, 1, complain
);
6115 /* Check for comparison of different enum types. */
6124 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
6125 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
6126 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
6127 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
6128 && (complain
& tf_warning
))
6130 warning (OPT_Wenum_compare
,
6131 "comparison between %q#T and %q#T",
6132 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
6139 /* We need to strip any leading REF_BIND so that bitfields
6140 don't cause errors. This should not remove any important
6141 conversions, because builtins don't apply to class
6142 objects directly. */
6143 conv
= cand
->convs
[0];
6144 if (conv
->kind
== ck_ref_bind
)
6145 conv
= next_conversion (conv
);
6146 arg1
= convert_like (conv
, arg1
, complain
);
6150 conv
= cand
->convs
[1];
6151 if (conv
->kind
== ck_ref_bind
)
6152 conv
= next_conversion (conv
);
6154 arg2
= decay_conversion (arg2
, complain
);
6156 /* We need to call warn_logical_operator before
6157 converting arg2 to a boolean_type, but after
6158 decaying an enumerator to its value. */
6159 if (complain
& tf_warning
)
6160 warn_logical_operator (loc
, code
, boolean_type_node
,
6161 code_orig_arg1
, arg1
,
6162 code_orig_arg2
, arg2
);
6164 arg2
= convert_like (conv
, arg2
, complain
);
6168 conv
= cand
->convs
[2];
6169 if (conv
->kind
== ck_ref_bind
)
6170 conv
= next_conversion (conv
);
6171 arg3
= convert_like (conv
, arg3
, complain
);
6177 user_defined_result_ready
:
6179 /* Free all the conversions we allocated. */
6180 obstack_free (&conversion_obstack
, p
);
6182 if (result
|| result_valid_p
)
6189 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6192 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6194 case TRUTH_ANDIF_EXPR
:
6195 case TRUTH_ORIF_EXPR
:
6196 case TRUTH_AND_EXPR
:
6198 if (complain
& tf_warning
)
6199 warn_logical_operator (loc
, code
, boolean_type_node
,
6200 code_orig_arg1
, arg1
,
6201 code_orig_arg2
, arg2
);
6209 if ((complain
& tf_warning
)
6210 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6211 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6212 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6213 if (complain
& tf_warning
&& warn_tautological_compare
)
6214 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6219 case TRUNC_DIV_EXPR
:
6224 case TRUNC_MOD_EXPR
:
6228 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6230 case UNARY_PLUS_EXPR
:
6233 case TRUTH_NOT_EXPR
:
6234 case PREINCREMENT_EXPR
:
6235 case POSTINCREMENT_EXPR
:
6236 case PREDECREMENT_EXPR
:
6237 case POSTDECREMENT_EXPR
:
6241 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6244 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6247 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6251 /* The caller will deal with these. */
6263 /* Wrapper for above. */
6266 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6267 tree arg1
, tree arg2
, tree arg3
,
6268 tree
*overload
, tsubst_flags_t complain
)
6271 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6272 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6273 overload
, complain
);
6274 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6278 /* CALL was returned by some call-building function; extract the actual
6279 CALL_EXPR from any bits that have been tacked on, e.g. by
6280 convert_from_reference. */
6283 extract_call_expr (tree call
)
6285 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6286 call
= TREE_OPERAND (call
, 1);
6287 if (REFERENCE_REF_P (call
))
6288 call
= TREE_OPERAND (call
, 0);
6289 if (TREE_CODE (call
) == TARGET_EXPR
)
6290 call
= TARGET_EXPR_INITIAL (call
);
6291 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6292 || TREE_CODE (call
) == AGGR_INIT_EXPR
6293 || call
== error_mark_node
);
6297 /* Returns true if FN has two parameters, of which the second has type
6301 second_parm_is_size_t (tree fn
)
6303 tree t
= FUNCTION_ARG_CHAIN (fn
);
6304 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6307 if (t
== void_list_node
)
6312 /* True if T, an allocation function, has std::align_val_t as its second
6316 aligned_allocation_fn_p (tree t
)
6318 if (!aligned_new_threshold
)
6321 tree a
= FUNCTION_ARG_CHAIN (t
);
6322 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6325 /* True if T is std::destroying_delete_t. */
6328 std_destroying_delete_t_p (tree t
)
6330 return (TYPE_CONTEXT (t
) == std_node
6331 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6334 /* A deallocation function with at least two parameters whose second parameter
6335 type is of type std::destroying_delete_t is a destroying operator delete. A
6336 destroying operator delete shall be a class member function named operator
6337 delete. [ Note: Array deletion cannot use a destroying operator
6338 delete. --end note ] */
6341 destroying_delete_p (tree t
)
6343 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6344 if (!a
|| !TREE_CHAIN (a
))
6346 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6347 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6357 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6358 function (3.7.4.2 [basic.stc.dynamic.deallocation]). If so, and DI is
6359 non-null, also set *DI. */
6362 usual_deallocation_fn_p (tree t
, dealloc_info
*di
)
6364 if (di
) *di
= dealloc_info();
6366 /* A template instance is never a usual deallocation function,
6367 regardless of its signature. */
6368 if (TREE_CODE (t
) == TEMPLATE_DECL
6369 || primary_template_specialization_p (t
))
6372 /* A usual deallocation function is a deallocation function whose parameters
6374 - optionally, a parameter of type std::destroying_delete_t, then
6375 - optionally, a parameter of type std::size_t, then
6376 - optionally, a parameter of type std::align_val_t. */
6377 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6378 tree chain
= FUNCTION_ARG_CHAIN (t
);
6379 if (chain
&& destroying_delete_p (t
))
6381 if (di
) di
->destroying
= TREE_VALUE (chain
);
6382 chain
= TREE_CHAIN (chain
);
6385 && (!global
|| flag_sized_deallocation
)
6386 && same_type_p (TREE_VALUE (chain
), size_type_node
))
6388 if (di
) di
->sized
= true;
6389 chain
= TREE_CHAIN (chain
);
6391 if (chain
&& aligned_new_threshold
6392 && same_type_p (TREE_VALUE (chain
), align_type_node
))
6394 if (di
) di
->aligned
= true;
6395 chain
= TREE_CHAIN (chain
);
6397 return (chain
== void_list_node
);
6400 /* Just return whether FN is a usual deallocation function. */
6403 usual_deallocation_fn_p (tree fn
)
6405 return usual_deallocation_fn_p (fn
, NULL
);
6408 /* Build a call to operator delete. This has to be handled very specially,
6409 because the restrictions on what signatures match are different from all
6410 other call instances. For a normal delete, only a delete taking (void *)
6411 or (void *, size_t) is accepted. For a placement delete, only an exact
6412 match with the placement new is accepted.
6414 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6415 ADDR is the pointer to be deleted.
6416 SIZE is the size of the memory block to be deleted.
6417 GLOBAL_P is true if the delete-expression should not consider
6418 class-specific delete operators.
6419 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6421 If this call to "operator delete" is being generated as part to
6422 deallocate memory allocated via a new-expression (as per [expr.new]
6423 which requires that if the initialization throws an exception then
6424 we call a deallocation function), then ALLOC_FN is the allocation
6428 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6429 bool global_p
, tree placement
,
6430 tree alloc_fn
, tsubst_flags_t complain
)
6432 tree fn
= NULL_TREE
;
6433 tree fns
, fnname
, type
, t
;
6434 dealloc_info di_fn
= { };
6436 if (addr
== error_mark_node
)
6437 return error_mark_node
;
6439 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6441 fnname
= ovl_op_identifier (false, code
);
6443 if (CLASS_TYPE_P (type
)
6444 && COMPLETE_TYPE_P (complete_type (type
))
6448 If the result of the lookup is ambiguous or inaccessible, or if
6449 the lookup selects a placement deallocation function, the
6450 program is ill-formed.
6452 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6454 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6455 if (fns
== error_mark_node
)
6456 return error_mark_node
;
6461 if (fns
== NULL_TREE
)
6462 fns
= lookup_name_nonclass (fnname
);
6464 /* Strip const and volatile from addr. */
6466 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6470 /* "A declaration of a placement deallocation function matches the
6471 declaration of a placement allocation function if it has the same
6472 number of parameters and, after parameter transformations (8.3.5),
6473 all parameter types except the first are identical."
6475 So we build up the function type we want and ask instantiate_type
6476 to get it for us. */
6477 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6478 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6479 t
= build_function_type (void_type_node
, t
);
6481 fn
= instantiate_type (t
, fns
, tf_none
);
6482 if (fn
== error_mark_node
)
6485 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6487 /* "If the lookup finds the two-parameter form of a usual deallocation
6488 function (3.7.4.2) and that function, considered as a placement
6489 deallocation function, would have been selected as a match for the
6490 allocation function, the program is ill-formed." */
6491 if (second_parm_is_size_t (fn
))
6493 const char *const msg1
6494 = G_("exception cleanup for this placement new selects "
6495 "non-placement operator delete");
6496 const char *const msg2
6497 = G_("%qD is a usual (non-placement) deallocation "
6498 "function in C++14 (or with -fsized-deallocation)");
6500 /* But if the class has an operator delete (void *), then that is
6501 the usual deallocation function, so we shouldn't complain
6502 about using the operator delete (void *, size_t). */
6503 if (DECL_CLASS_SCOPE_P (fn
))
6504 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6508 if (usual_deallocation_fn_p (elt
)
6509 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6512 /* Before C++14 a two-parameter global deallocation function is
6513 always a placement deallocation function, but warn if
6515 else if (!flag_sized_deallocation
)
6517 if (complain
& tf_warning
)
6519 auto_diagnostic_group d
;
6520 if (warning (OPT_Wc__14_compat
, msg1
))
6521 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6526 if (complain
& tf_warning_or_error
)
6528 auto_diagnostic_group d
;
6529 if (permerror (input_location
, msg1
))
6531 /* Only mention C++14 for namespace-scope delete. */
6532 if (DECL_NAMESPACE_SCOPE_P (fn
))
6533 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6535 inform (DECL_SOURCE_LOCATION (fn
),
6536 "%qD is a usual (non-placement) deallocation "
6541 return error_mark_node
;
6546 /* "Any non-placement deallocation function matches a non-placement
6547 allocation function. If the lookup finds a single matching
6548 deallocation function, that function will be called; otherwise, no
6549 deallocation function will be called." */
6550 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6553 dealloc_info di_elt
;
6554 if (usual_deallocation_fn_p (elt
, &di_elt
))
6563 /* -- If any of the deallocation functions is a destroying
6564 operator delete, all deallocation functions that are not
6565 destroying operator deletes are eliminated from further
6567 if (di_elt
.destroying
!= di_fn
.destroying
)
6569 if (di_elt
.destroying
)
6577 /* -- If the type has new-extended alignment, a function with a
6578 parameter of type std::align_val_t is preferred; otherwise a
6579 function without such a parameter is preferred. If exactly one
6580 preferred function is found, that function is selected and the
6581 selection process terminates. If more than one preferred
6582 function is found, all non-preferred functions are eliminated
6583 from further consideration. */
6584 if (aligned_new_threshold
)
6586 bool want_align
= type_has_new_extended_alignment (type
);
6587 if (di_elt
.aligned
!= di_fn
.aligned
)
6589 if (want_align
== di_elt
.aligned
)
6598 /* -- If the deallocation functions have class scope, the one
6599 without a parameter of type std::size_t is selected. */
6601 if (DECL_CLASS_SCOPE_P (fn
))
6604 /* -- If the type is complete and if, for the second alternative
6605 (delete array) only, the operand is a pointer to a class type
6606 with a non-trivial destructor or a (possibly multi-dimensional)
6607 array thereof, the function with a parameter of type std::size_t
6610 -- Otherwise, it is unspecified whether a deallocation function
6611 with a parameter of type std::size_t is selected. */
6614 want_size
= COMPLETE_TYPE_P (type
);
6615 if (code
== VEC_DELETE_EXPR
6616 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6617 /* We need a cookie to determine the array size. */
6620 gcc_assert (di_fn
.sized
!= di_elt
.sized
);
6621 if (want_size
== di_elt
.sized
)
6629 /* If we have a matching function, call it. */
6632 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6634 /* If the FN is a member function, make sure that it is
6636 if (BASELINK_P (fns
))
6637 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6640 /* Core issue 901: It's ok to new a type with deleted delete. */
6641 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6646 /* The placement args might not be suitable for overload
6647 resolution at this point, so build the call directly. */
6648 int nargs
= call_expr_nargs (placement
);
6649 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6652 for (i
= 1; i
< nargs
; i
++)
6653 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6654 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6655 return error_mark_node
;
6656 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6660 tree destroying
= di_fn
.destroying
;
6663 /* Strip const and volatile from addr but retain the type of the
6665 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6666 rtype
= cv_unqualified (rtype
);
6667 rtype
= TYPE_POINTER_TO (rtype
);
6668 addr
= cp_convert (rtype
, oaddr
, complain
);
6669 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6674 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6675 args
->quick_push (addr
);
6677 args
->quick_push (destroying
);
6679 args
->quick_push (size
);
6682 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6683 args
->quick_push (al
);
6685 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6686 release_tree_vector (args
);
6693 If no unambiguous matching deallocation function can be found,
6694 propagating the exception does not cause the object's memory to
6698 if ((complain
& tf_warning
)
6700 warning (0, "no corresponding deallocation function for %qD",
6705 if (complain
& tf_error
)
6706 error ("no suitable %<operator %s%> for %qT",
6707 OVL_OP_INFO (false, code
)->name
, type
);
6708 return error_mark_node
;
6711 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6714 If ISSUE_ERROR is true, then issue an error about the
6715 access, followed by a note showing the declaration.
6716 Otherwise, just show the note. */
6719 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6721 if (TREE_PRIVATE (decl
))
6724 error ("%q#D is private within this context", diag_decl
);
6725 inform (DECL_SOURCE_LOCATION (diag_decl
),
6726 "declared private here");
6728 else if (TREE_PROTECTED (decl
))
6731 error ("%q#D is protected within this context", diag_decl
);
6732 inform (DECL_SOURCE_LOCATION (diag_decl
),
6733 "declared protected here");
6738 error ("%q#D is inaccessible within this context", diag_decl
);
6739 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6743 /* If the current scope isn't allowed to access DECL along
6744 BASETYPE_PATH, give an error. The most derived class in
6745 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6746 the declaration to use in the error diagnostic. */
6749 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6750 tsubst_flags_t complain
, access_failure_info
*afi
)
6752 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6754 if (flag_new_inheriting_ctors
6755 && DECL_INHERITED_CTOR (decl
))
6757 /* 7.3.3/18: The additional constructors are accessible if they would be
6758 accessible when used to construct an object of the corresponding base
6760 decl
= strip_inheriting_ctors (decl
);
6761 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6762 ba_any
, NULL
, complain
);
6765 if (!accessible_p (basetype_path
, decl
, true))
6767 if (flag_new_inheriting_ctors
)
6768 diag_decl
= strip_inheriting_ctors (diag_decl
);
6769 if (complain
& tf_error
)
6770 complain_about_access (decl
, diag_decl
, true);
6772 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6779 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6780 bitwise or of LOOKUP_* values. If any errors are warnings are
6781 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6782 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6786 build_temp (tree expr
, tree type
, int flags
,
6787 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6790 vec
<tree
, va_gc
> *args
;
6792 *diagnostic_kind
= DK_UNSPECIFIED
;
6794 /* If the source is a packed field, calling the copy constructor will require
6795 binding the field to the reference parameter to the copy constructor, and
6796 we'll end up with an infinite loop. If we can use a bitwise copy, then
6798 if ((lvalue_kind (expr
) & clk_packed
)
6799 && CLASS_TYPE_P (TREE_TYPE (expr
))
6800 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6801 return get_target_expr_sfinae (expr
, complain
);
6803 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6804 args
= make_tree_vector_single (expr
);
6805 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6806 &args
, type
, flags
, complain
);
6807 release_tree_vector (args
);
6808 if (warningcount
+ werrorcount
> savew
)
6809 *diagnostic_kind
= DK_WARNING
;
6810 else if (errorcount
> savee
)
6811 *diagnostic_kind
= DK_ERROR
;
6815 /* Get any location for EXPR, falling back to input_location.
6817 If the result is in a system header and is the virtual location for
6818 a token coming from the expansion of a macro, unwind it to the
6819 location of the expansion point of the macro (e.g. to avoid the
6820 diagnostic being suppressed for expansions of NULL where "NULL" is
6821 in a system header). */
6824 get_location_for_expr_unwinding_for_system_header (tree expr
)
6826 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6827 loc
= expansion_point_location_if_in_system_header (loc
);
6831 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6832 Also handle a subset of zero as null warnings.
6833 EXPR is implicitly converted to type TOTYPE.
6834 FN and ARGNUM are used for diagnostics. */
6837 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6839 /* Issue warnings about peculiar, but valid, uses of NULL. */
6840 if (TREE_CODE (totype
) != BOOLEAN_TYPE
6841 && ARITHMETIC_TYPE_P (totype
)
6842 && null_node_p (expr
))
6844 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6847 auto_diagnostic_group d
;
6848 if (warning_at (loc
, OPT_Wconversion_null
,
6849 "passing NULL to non-pointer argument %P of %qD",
6851 inform (get_fndecl_argument_location (fn
, argnum
),
6855 warning_at (loc
, OPT_Wconversion_null
,
6856 "converting to non-pointer type %qT from NULL", totype
);
6859 /* Issue warnings if "false" is converted to a NULL pointer */
6860 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6861 && TYPE_PTR_P (totype
))
6863 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6866 auto_diagnostic_group d
;
6867 if (warning_at (loc
, OPT_Wconversion_null
,
6868 "converting %<false%> to pointer type for argument "
6869 "%P of %qD", argnum
, fn
))
6870 inform (get_fndecl_argument_location (fn
, argnum
),
6874 warning_at (loc
, OPT_Wconversion_null
,
6875 "converting %<false%> to pointer type %qT", totype
);
6877 /* Handle zero as null pointer warnings for cases other
6878 than EQ_EXPR and NE_EXPR */
6879 else if ((TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
))
6880 && null_ptr_cst_p (expr
))
6882 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6883 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6887 /* We gave a diagnostic during a conversion. If this was in the second
6888 standard conversion sequence of a user-defined conversion sequence, say
6889 which user-defined conversion. */
6892 maybe_print_user_conv_context (conversion
*convs
)
6894 if (convs
->user_conv_p
)
6895 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6896 if (t
->kind
== ck_user
)
6898 print_z_candidate (0, " after user-defined conversion:",
6904 /* Locate the parameter with the given index within FNDECL.
6905 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6906 Return the location of the FNDECL itself if there are problems. */
6909 get_fndecl_argument_location (tree fndecl
, int argnum
)
6911 /* The locations of implicitly-declared functions are likely to be
6912 more meaningful than those of their parameters. */
6913 if (DECL_ARTIFICIAL (fndecl
))
6914 return DECL_SOURCE_LOCATION (fndecl
);
6919 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6920 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6921 i
< argnum
&& param
;
6922 i
++, param
= TREE_CHAIN (param
))
6925 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6926 return the location of FNDECL. */
6928 return DECL_SOURCE_LOCATION (fndecl
);
6930 return DECL_SOURCE_LOCATION (param
);
6933 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6934 within its declaration (or the fndecl itself if something went
6938 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6941 inform (get_fndecl_argument_location (fn
, argnum
),
6942 " initializing argument %P of %qD", argnum
, fn
);
6945 /* Perform the conversions in CONVS on the expression EXPR. FN and
6946 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6947 indicates the `this' argument of a method. INNER is nonzero when
6948 being called to continue a conversion chain. It is negative when a
6949 reference binding will be applied, positive otherwise. If
6950 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6951 conversions will be emitted if appropriate. If C_CAST_P is true,
6952 this conversion is coming from a C-style cast; in that case,
6953 conversions to inaccessible bases are permitted. */
6956 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6957 bool issue_conversion_warnings
,
6958 bool c_cast_p
, tsubst_flags_t complain
)
6960 tree totype
= convs
->type
;
6961 diagnostic_t diag_kind
;
6963 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
6965 if (convs
->bad_p
&& !(complain
& tf_error
))
6966 return error_mark_node
;
6969 && convs
->kind
!= ck_user
6970 && convs
->kind
!= ck_list
6971 && convs
->kind
!= ck_ambig
6972 && (convs
->kind
!= ck_ref_bind
6973 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6974 && (convs
->kind
!= ck_rvalue
6975 || SCALAR_TYPE_P (totype
))
6976 && convs
->kind
!= ck_base
)
6978 bool complained
= false;
6979 conversion
*t
= convs
;
6981 /* Give a helpful error if this is bad because of excess braces. */
6982 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6983 && SCALAR_TYPE_P (totype
)
6984 && CONSTRUCTOR_NELTS (expr
) > 0
6985 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6987 complained
= permerror (loc
, "too many braces around initializer "
6989 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6990 && CONSTRUCTOR_NELTS (expr
) == 1)
6991 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6994 /* Give a helpful error if this is bad because a conversion to bool
6995 from std::nullptr_t requires direct-initialization. */
6996 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6997 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6998 complained
= permerror (loc
, "converting to %qH from %qI requires "
6999 "direct-initialization",
7000 totype
, TREE_TYPE (expr
));
7002 for (; t
; t
= next_conversion (t
))
7004 if (t
->kind
== ck_user
&& t
->cand
->reason
)
7006 auto_diagnostic_group d
;
7007 complained
= permerror (loc
, "invalid user-defined conversion "
7008 "from %qH to %qI", TREE_TYPE (expr
),
7011 print_z_candidate (loc
, "candidate is:", t
->cand
);
7012 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7013 /*issue_conversion_warnings=*/false,
7016 if (convs
->kind
== ck_ref_bind
)
7017 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
7018 LOOKUP_NORMAL
, NULL_TREE
,
7021 expr
= cp_convert (totype
, expr
, complain
);
7023 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7026 else if (t
->kind
== ck_user
|| !t
->bad_p
)
7028 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7029 /*issue_conversion_warnings=*/false,
7034 else if (t
->kind
== ck_ambig
)
7035 return convert_like_real (t
, expr
, fn
, argnum
,
7036 /*issue_conversion_warnings=*/false,
7039 else if (t
->kind
== ck_identity
)
7044 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
7045 gcc_rich_location
richloc (loc
, &label
);
7046 complained
= permerror (&richloc
,
7047 "invalid conversion from %qH to %qI",
7048 TREE_TYPE (expr
), totype
);
7051 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7053 return cp_convert (totype
, expr
, complain
);
7056 if (issue_conversion_warnings
&& (complain
& tf_warning
))
7057 conversion_null_warnings (totype
, expr
, fn
, argnum
);
7059 switch (convs
->kind
)
7063 struct z_candidate
*cand
= convs
->cand
;
7066 /* We chose the surrogate function from add_conv_candidate, now we
7067 actually need to build the conversion. */
7068 cand
= build_user_type_conversion_1 (totype
, expr
,
7069 LOOKUP_NO_CONVERSION
, complain
);
7071 tree convfn
= cand
->fn
;
7073 /* When converting from an init list we consider explicit
7074 constructors, but actually trying to call one is an error. */
7075 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
7076 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
7077 /* Unless this is for direct-list-initialization. */
7078 && (!CONSTRUCTOR_IS_DIRECT_INIT (expr
) || convs
->need_temporary_p
)
7079 /* And in C++98 a default constructor can't be explicit. */
7080 && cxx_dialect
>= cxx11
)
7082 if (!(complain
& tf_error
))
7083 return error_mark_node
;
7084 location_t loc
= location_of (expr
);
7085 if (CONSTRUCTOR_NELTS (expr
) == 0
7086 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
7088 auto_diagnostic_group d
;
7089 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
7090 "would use explicit constructor %qD",
7092 inform (loc
, "in C++11 and above a default constructor "
7096 error ("converting to %qT from initializer list would use "
7097 "explicit constructor %qD", totype
, convfn
);
7100 /* If we're initializing from {}, it's value-initialization. */
7101 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7102 && CONSTRUCTOR_NELTS (expr
) == 0
7103 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
)
7104 && !processing_template_decl
)
7106 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
7107 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
7108 return error_mark_node
;
7109 expr
= build_value_init (totype
, complain
);
7110 expr
= get_target_expr_sfinae (expr
, complain
);
7111 if (expr
!= error_mark_node
)
7113 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7114 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
7119 /* We don't know here whether EXPR is being used as an lvalue or
7120 rvalue, but we know it's read. */
7121 mark_exp_read (expr
);
7123 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
7125 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
7128 /* If this is a constructor or a function returning an aggr type,
7129 we need to build up a TARGET_EXPR. */
7130 if (DECL_CONSTRUCTOR_P (convfn
))
7132 expr
= build_cplus_new (totype
, expr
, complain
);
7134 /* Remember that this was list-initialization. */
7135 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
7136 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7142 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
7144 int nelts
= CONSTRUCTOR_NELTS (expr
);
7146 expr
= build_value_init (totype
, complain
);
7147 else if (nelts
== 1)
7148 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7152 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7153 /*read_p=*/true, UNKNOWN_LOCATION
,
7154 /*reject_builtin=*/true);
7156 if (type_unknown_p (expr
))
7157 expr
= instantiate_type (totype
, expr
, complain
);
7158 if (expr
== null_node
7159 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7160 /* If __null has been converted to an integer type, we do not want to
7161 continue to warn about uses of EXPR as an integer, rather than as a
7163 expr
= build_int_cst (totype
, 0);
7166 /* We leave bad_p off ck_ambig because overload resolution considers
7167 it valid, it just fails when we try to perform it. So we need to
7168 check complain here, too. */
7169 if (complain
& tf_error
)
7171 /* Call build_user_type_conversion again for the error. */
7172 int flags
= (convs
->need_temporary_p
7173 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7174 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7175 gcc_assert (seen_error ());
7176 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7178 return error_mark_node
;
7182 /* Conversion to std::initializer_list<T>. */
7183 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7184 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7189 tree val
; unsigned ix
;
7191 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7193 /* Convert all the elements. */
7194 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7196 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
,
7197 argnum
, false, false, complain
);
7198 if (sub
== error_mark_node
)
7200 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7201 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7202 return error_mark_node
;
7203 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
),
7205 if (!TREE_CONSTANT (sub
))
7206 TREE_CONSTANT (new_ctor
) = false;
7208 /* Build up the array. */
7209 elttype
= cp_build_qualified_type
7210 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7211 array
= build_array_of_n_type (elttype
, len
);
7212 array
= finish_compound_literal (array
, new_ctor
, complain
);
7213 /* Take the address explicitly rather than via decay_conversion
7214 to avoid the error about taking the address of a temporary. */
7215 array
= cp_build_addr_expr (array
, complain
);
7218 array
= nullptr_node
;
7220 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7221 if (array
== error_mark_node
)
7222 return error_mark_node
;
7224 /* Build up the initializer_list object. Note: fail gracefully
7225 if the object cannot be completed because, for example, no
7226 definition is provided (c++/80956). */
7227 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7229 return error_mark_node
;
7230 tree field
= next_initializable_field (TYPE_FIELDS (totype
));
7231 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7232 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7233 field
= next_initializable_field (DECL_CHAIN (field
));
7234 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7235 tree new_ctor
= build_constructor (totype
, vec
);
7236 return get_target_expr_sfinae (new_ctor
, complain
);
7240 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7242 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7243 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7244 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7246 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7248 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7251 expr
= reshape_init (totype
, expr
, complain
);
7252 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7254 if (expr
!= error_mark_node
)
7255 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7262 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7263 convs
->kind
== ck_ref_bind
7264 ? issue_conversion_warnings
: false,
7265 c_cast_p
, complain
);
7266 if (expr
== error_mark_node
)
7267 return error_mark_node
;
7269 switch (convs
->kind
)
7272 expr
= decay_conversion (expr
, complain
);
7273 if (expr
== error_mark_node
)
7275 if (complain
& tf_error
)
7277 auto_diagnostic_group d
;
7278 maybe_print_user_conv_context (convs
);
7279 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7281 return error_mark_node
;
7284 if (! MAYBE_CLASS_TYPE_P (totype
))
7287 /* Don't introduce copies when passing arguments along to the inherited
7289 if (current_function_decl
7290 && flag_new_inheriting_ctors
7291 && DECL_INHERITED_CTOR (current_function_decl
))
7294 if (TREE_CODE (expr
) == TARGET_EXPR
7295 && TARGET_EXPR_LIST_INIT_P (expr
))
7296 /* Copy-list-initialization doesn't actually involve a copy. */
7301 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7303 /* We are going to bind a reference directly to a base-class
7304 subobject of EXPR. */
7305 /* Build an expression for `*((base*) &expr)'. */
7306 expr
= convert_to_base (expr
, totype
,
7307 !c_cast_p
, /*nonnull=*/true, complain
);
7311 /* Copy-initialization where the cv-unqualified version of the source
7312 type is the same class as, or a derived class of, the class of the
7313 destination [is treated as direct-initialization]. [dcl.init] */
7314 flags
= LOOKUP_NORMAL
;
7315 if (convs
->user_conv_p
)
7316 /* This conversion is being done in the context of a user-defined
7317 conversion (i.e. the second step of copy-initialization), so
7318 don't allow any more. */
7319 flags
|= LOOKUP_NO_CONVERSION
;
7321 flags
|= LOOKUP_ONLYCONVERTING
;
7322 if (convs
->rvaluedness_matches_p
)
7323 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7324 flags
|= LOOKUP_PREFER_RVALUE
;
7325 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7326 if (diag_kind
&& complain
)
7328 auto_diagnostic_group d
;
7329 maybe_print_user_conv_context (convs
);
7330 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7333 return build_cplus_new (totype
, expr
, complain
);
7337 tree ref_type
= totype
;
7339 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7341 tree extype
= TREE_TYPE (expr
);
7342 auto_diagnostic_group d
;
7343 if (TYPE_REF_IS_RVALUE (ref_type
)
7345 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7346 "lvalue of type %qI", totype
, extype
);
7347 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7348 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7349 error_at (loc
, "cannot bind non-const lvalue reference of "
7350 "type %qH to an rvalue of type %qI", totype
, extype
);
7351 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7352 error_at (loc
, "binding reference of type %qH to %qI "
7353 "discards qualifiers", totype
, extype
);
7356 maybe_print_user_conv_context (convs
);
7357 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7359 return error_mark_node
;
7362 /* If necessary, create a temporary.
7364 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7365 that need temporaries, even when their types are reference
7366 compatible with the type of reference being bound, so the
7367 upcoming call to cp_build_addr_expr doesn't fail. */
7368 if (convs
->need_temporary_p
7369 || TREE_CODE (expr
) == CONSTRUCTOR
7370 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7372 /* Otherwise, a temporary of type "cv1 T1" is created and
7373 initialized from the initializer expression using the rules
7374 for a non-reference copy-initialization (8.5). */
7376 tree type
= TREE_TYPE (ref_type
);
7377 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7379 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7380 (type
, next_conversion (convs
)->type
));
7381 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7382 && !TYPE_REF_IS_RVALUE (ref_type
))
7384 /* If the reference is volatile or non-const, we
7385 cannot create a temporary. */
7386 if (lvalue
& clk_bitfield
)
7387 error_at (loc
, "cannot bind bitfield %qE to %qT",
7389 else if (lvalue
& clk_packed
)
7390 error_at (loc
, "cannot bind packed field %qE to %qT",
7393 error_at (loc
, "cannot bind rvalue %qE to %qT",
7395 return error_mark_node
;
7397 /* If the source is a packed field, and we must use a copy
7398 constructor, then building the target expr will require
7399 binding the field to the reference parameter to the
7400 copy constructor, and we'll end up with an infinite
7401 loop. If we can use a bitwise copy, then we'll be
7403 if ((lvalue
& clk_packed
)
7404 && CLASS_TYPE_P (type
)
7405 && type_has_nontrivial_copy_init (type
))
7407 error_at (loc
, "cannot bind packed field %qE to %qT",
7409 return error_mark_node
;
7411 if (lvalue
& clk_bitfield
)
7413 expr
= convert_bitfield_to_declared_type (expr
);
7414 expr
= fold_convert (type
, expr
);
7416 expr
= build_target_expr_with_type (expr
, type
, complain
);
7419 /* Take the address of the thing to which we will bind the
7421 expr
= cp_build_addr_expr (expr
, complain
);
7422 if (expr
== error_mark_node
)
7423 return error_mark_node
;
7425 /* Convert it to a pointer to the type referred to by the
7426 reference. This will adjust the pointer if a derived to
7427 base conversion is being performed. */
7428 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7430 /* Convert the pointer to the desired reference type. */
7431 return build_nop (ref_type
, expr
);
7435 return decay_conversion (expr
, complain
);
7438 /* ??? Should the address of a transaction-safe pointer point to the TM
7439 clone, and this conversion look up the primary function? */
7440 return build_nop (totype
, expr
);
7443 /* Warn about deprecated conversion if appropriate. */
7444 if (complain
& tf_warning
)
7445 string_conv_p (totype
, expr
, 1);
7450 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7451 /*nonnull=*/false, complain
);
7452 return build_nop (totype
, expr
);
7455 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7456 c_cast_p
, complain
);
7462 if (convs
->check_narrowing
7463 && !check_narrowing (totype
, expr
, complain
,
7464 convs
->check_narrowing_const_only
))
7465 return error_mark_node
;
7467 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7468 if (issue_conversion_warnings
)
7469 expr
= cp_convert_and_check (totype
, expr
, complain
);
7471 expr
= cp_convert (totype
, expr
, complain
);
7476 /* ARG is being passed to a varargs function. Perform any conversions
7477 required. Return the converted value. */
7480 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7483 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
7487 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7488 standard conversions are performed. */
7489 arg
= decay_conversion (arg
, complain
);
7490 arg_type
= TREE_TYPE (arg
);
7493 If the argument has integral or enumeration type that is subject
7494 to the integral promotions (_conv.prom_), or a floating point
7495 type that is subject to the floating point promotion
7496 (_conv.fpprom_), the value of the argument is converted to the
7497 promoted type before the call. */
7498 if (TREE_CODE (arg_type
) == REAL_TYPE
7499 && (TYPE_PRECISION (arg_type
)
7500 < TYPE_PRECISION (double_type_node
))
7501 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7503 if ((complain
& tf_warning
)
7504 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7505 warning_at (loc
, OPT_Wdouble_promotion
,
7506 "implicit conversion from %qH to %qI when passing "
7507 "argument to function",
7508 arg_type
, double_type_node
);
7509 arg
= convert_to_real_nofold (double_type_node
, arg
);
7511 else if (NULLPTR_TYPE_P (arg_type
))
7512 arg
= null_pointer_node
;
7513 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7515 if (SCOPED_ENUM_P (arg_type
))
7517 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7519 prom
= cp_perform_integral_promotions (prom
, complain
);
7520 if (abi_version_crosses (6)
7521 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7522 && (complain
& tf_warning
))
7523 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
7524 "%qT before %<-fabi-version=6%>, %qT after", arg_type
,
7525 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7526 if (!abi_version_at_least (6))
7530 arg
= cp_perform_integral_promotions (arg
, complain
);
7533 arg
= require_complete_type_sfinae (arg
, complain
);
7534 arg_type
= TREE_TYPE (arg
);
7536 if (arg
!= error_mark_node
7537 /* In a template (or ill-formed code), we can have an incomplete type
7538 even after require_complete_type_sfinae, in which case we don't know
7539 whether it has trivial copy or not. */
7540 && COMPLETE_TYPE_P (arg_type
)
7541 && !cp_unevaluated_operand
)
7543 /* [expr.call] 5.2.2/7:
7544 Passing a potentially-evaluated argument of class type (Clause 9)
7545 with a non-trivial copy constructor or a non-trivial destructor
7546 with no corresponding parameter is conditionally-supported, with
7547 implementation-defined semantics.
7549 We support it as pass-by-invisible-reference, just like a normal
7552 If the call appears in the context of a sizeof expression,
7553 it is not potentially-evaluated. */
7554 if (type_has_nontrivial_copy_init (arg_type
)
7555 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7557 arg
= force_rvalue (arg
, complain
);
7558 if (complain
& tf_warning
)
7559 warning (OPT_Wconditionally_supported
,
7560 "passing objects of non-trivially-copyable "
7561 "type %q#T through %<...%> is conditionally supported",
7563 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7565 /* Build up a real lvalue-to-rvalue conversion in case the
7566 copy constructor is trivial but not callable. */
7567 else if (CLASS_TYPE_P (arg_type
))
7568 force_rvalue (arg
, complain
);
7575 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7578 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7580 if (processing_template_decl
)
7582 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7583 SET_EXPR_LOCATION (r
, loc
);
7587 type
= complete_type_or_else (type
, NULL_TREE
);
7589 if (expr
== error_mark_node
|| !type
)
7590 return error_mark_node
;
7592 expr
= mark_lvalue_use (expr
);
7594 if (TYPE_REF_P (type
))
7596 error ("cannot receive reference type %qT through %<...%>", type
);
7597 return error_mark_node
;
7600 if (type_has_nontrivial_copy_init (type
)
7601 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7603 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7604 it as pass by invisible reference. */
7605 warning_at (loc
, OPT_Wconditionally_supported
,
7606 "receiving objects of non-trivially-copyable type %q#T "
7607 "through %<...%> is conditionally-supported", type
);
7609 tree ref
= cp_build_reference_type (type
, false);
7610 expr
= build_va_arg (loc
, expr
, ref
);
7611 return convert_from_reference (expr
);
7614 tree ret
= build_va_arg (loc
, expr
, type
);
7615 if (CLASS_TYPE_P (type
))
7616 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7617 know how to handle it. */
7618 ret
= get_target_expr (ret
);
7622 /* TYPE has been given to va_arg. Apply the default conversions which
7623 would have happened when passed via ellipsis. Return the promoted
7624 type, or the passed type if there is no change. */
7627 cxx_type_promotes_to (tree type
)
7631 /* Perform the array-to-pointer and function-to-pointer
7633 type
= type_decays_to (type
);
7635 promote
= type_promotes_to (type
);
7636 if (same_type_p (type
, promote
))
7642 /* ARG is a default argument expression being passed to a parameter of
7643 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7644 zero-based argument number. Do any required conversions. Return
7645 the converted value. */
7647 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7649 push_defarg_context (tree fn
)
7650 { vec_safe_push (default_arg_context
, fn
); }
7653 pop_defarg_context (void)
7654 { default_arg_context
->pop (); }
7657 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7658 tsubst_flags_t complain
)
7663 /* See through clones. */
7664 fn
= DECL_ORIGIN (fn
);
7665 /* And inheriting ctors. */
7666 if (flag_new_inheriting_ctors
)
7667 fn
= strip_inheriting_ctors (fn
);
7669 /* Detect recursion. */
7670 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7673 if (complain
& tf_error
)
7674 error ("recursive evaluation of default argument for %q#D", fn
);
7675 return error_mark_node
;
7678 /* If the ARG is an unparsed default argument expression, the
7679 conversion cannot be performed. */
7680 if (TREE_CODE (arg
) == DEFAULT_ARG
)
7682 if (complain
& tf_error
)
7683 error ("call to %qD uses the default argument for parameter %P, which "
7684 "is not yet defined", fn
, parmnum
);
7685 return error_mark_node
;
7688 push_defarg_context (fn
);
7690 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7691 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7697 The names in the expression are bound, and the semantic
7698 constraints are checked, at the point where the default
7699 expressions appears.
7701 we must not perform access checks here. */
7702 push_deferring_access_checks (dk_no_check
);
7703 /* We must make a copy of ARG, in case subsequent processing
7704 alters any part of it. */
7705 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7707 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7708 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7710 arg
= convert_for_arg_passing (type
, arg
, complain
);
7711 pop_deferring_access_checks();
7713 pop_defarg_context ();
7718 /* Returns the type which will really be used for passing an argument of
7722 type_passed_as (tree type
)
7724 /* Pass classes with copy ctors by invisible reference. */
7725 if (TREE_ADDRESSABLE (type
))
7727 type
= build_reference_type (type
);
7728 /* There are no other pointers to this temporary. */
7729 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7731 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7732 && INTEGRAL_TYPE_P (type
)
7733 && COMPLETE_TYPE_P (type
)
7734 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7735 type
= integer_type_node
;
7740 /* Actually perform the appropriate conversion. */
7743 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7747 /* If VAL is a bitfield, then -- since it has already been converted
7748 to TYPE -- it cannot have a precision greater than TYPE.
7750 If it has a smaller precision, we must widen it here. For
7751 example, passing "int f:3;" to a function expecting an "int" will
7752 not result in any conversion before this point.
7754 If the precision is the same we must not risk widening. For
7755 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7756 often have type "int", even though the C++ type for the field is
7757 "long long". If the value is being passed to a function
7758 expecting an "int", then no conversions will be required. But,
7759 if we call convert_bitfield_to_declared_type, the bitfield will
7760 be converted to "long long". */
7761 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7763 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7764 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7766 if (val
== error_mark_node
)
7768 /* Pass classes with copy ctors by invisible reference. */
7769 else if (TREE_ADDRESSABLE (type
))
7770 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7771 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7772 && INTEGRAL_TYPE_P (type
)
7773 && COMPLETE_TYPE_P (type
)
7774 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7775 val
= cp_perform_integral_promotions (val
, complain
);
7776 if (complain
& tf_warning
)
7778 if (warn_suggest_attribute_format
)
7780 tree rhstype
= TREE_TYPE (val
);
7781 const enum tree_code coder
= TREE_CODE (rhstype
);
7782 const enum tree_code codel
= TREE_CODE (type
);
7783 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7785 && check_missing_format_attribute (type
, rhstype
))
7786 warning (OPT_Wsuggest_attribute_format
,
7787 "argument of function call might be a candidate "
7788 "for a format attribute");
7790 maybe_warn_parm_abi (type
, cp_expr_loc_or_loc (val
, input_location
));
7793 if (complain
& tf_warning
)
7794 warn_for_address_or_pointer_of_packed_member (type
, val
);
7799 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7800 which just decay_conversion or no conversions at all should be done.
7801 This is true for some builtins which don't act like normal functions.
7802 Return 2 if no conversions at all should be done, 1 if just
7803 decay_conversion. Return 3 for special treatment of the 3rd argument
7804 for __builtin_*_overflow_p. */
7807 magic_varargs_p (tree fn
)
7809 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7810 switch (DECL_FUNCTION_CODE (fn
))
7812 case BUILT_IN_CLASSIFY_TYPE
:
7813 case BUILT_IN_CONSTANT_P
:
7814 case BUILT_IN_NEXT_ARG
:
7815 case BUILT_IN_VA_START
:
7818 case BUILT_IN_ADD_OVERFLOW_P
:
7819 case BUILT_IN_SUB_OVERFLOW_P
:
7820 case BUILT_IN_MUL_OVERFLOW_P
:
7824 return lookup_attribute ("type generic",
7825 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7831 /* Returns the decl of the dispatcher function if FN is a function version. */
7834 get_function_version_dispatcher (tree fn
)
7836 tree dispatcher_decl
= NULL
;
7838 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7839 && DECL_FUNCTION_VERSIONED (fn
));
7841 gcc_assert (targetm
.get_function_versions_dispatcher
);
7842 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7844 if (dispatcher_decl
== NULL
)
7846 error_at (input_location
, "use of multiversioned function "
7847 "without a default");
7851 retrofit_lang_decl (dispatcher_decl
);
7852 gcc_assert (dispatcher_decl
!= NULL
);
7853 return dispatcher_decl
;
7856 /* fn is a function version dispatcher that is marked used. Mark all the
7857 semantically identical function versions it will dispatch as used. */
7860 mark_versions_used (tree fn
)
7862 struct cgraph_node
*node
;
7863 struct cgraph_function_version_info
*node_v
;
7864 struct cgraph_function_version_info
*it_v
;
7866 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7868 node
= cgraph_node::get (fn
);
7872 gcc_assert (node
->dispatcher_function
);
7874 node_v
= node
->function_version ();
7878 /* All semantically identical versions are chained. Traverse and mark each
7879 one of them as used. */
7880 it_v
= node_v
->next
;
7881 while (it_v
!= NULL
)
7883 mark_used (it_v
->this_node
->decl
);
7888 /* Build a call to "the copy constructor" for the type of A, even if it
7889 wouldn't be selected by normal overload resolution. Used for
7893 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7895 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7896 tree binfo
= TYPE_BINFO (ctype
);
7897 tree copy
= get_copy_ctor (ctype
, complain
);
7898 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7899 tree ob
= build_dummy_object (ctype
);
7900 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7901 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7902 LOOKUP_NORMAL
, NULL
, complain
);
7903 release_tree_vector (args
);
7907 /* Return true iff T refers to a base field. */
7910 is_base_field_ref (tree t
)
7913 if (TREE_CODE (t
) == ADDR_EXPR
)
7914 t
= TREE_OPERAND (t
, 0);
7915 if (TREE_CODE (t
) == COMPONENT_REF
)
7916 t
= TREE_OPERAND (t
, 1);
7917 if (TREE_CODE (t
) == FIELD_DECL
)
7918 return DECL_FIELD_IS_BASE (t
);
7922 /* We can't elide a copy from a function returning by value to a base
7923 subobject, as the callee might clobber tail padding. Return true iff this
7924 could be that case. */
7927 unsafe_copy_elision_p (tree target
, tree exp
)
7929 /* Copy elision only happens with a TARGET_EXPR. */
7930 if (TREE_CODE (exp
) != TARGET_EXPR
)
7932 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7933 /* It's safe to elide the copy for a class with no tail padding. */
7934 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7936 /* It's safe to elide the copy if we aren't initializing a base object. */
7937 if (!is_base_field_ref (target
))
7939 tree init
= TARGET_EXPR_INITIAL (exp
);
7940 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7941 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7942 init
= TREE_OPERAND (init
, 1);
7943 if (TREE_CODE (init
) == COND_EXPR
)
7945 /* We'll end up copying from each of the arms of the COND_EXPR directly
7946 into the target, so look at them. */
7947 if (tree op
= TREE_OPERAND (init
, 1))
7948 if (unsafe_copy_elision_p (target
, op
))
7950 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7952 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7953 && !AGGR_INIT_VIA_CTOR_P (init
));
7956 /* True iff C is a conversion that binds a reference to a prvalue. */
7959 conv_binds_ref_to_prvalue (conversion
*c
)
7961 if (c
->kind
!= ck_ref_bind
)
7963 if (c
->need_temporary_p
)
7966 c
= next_conversion (c
);
7968 if (c
->kind
== ck_rvalue
)
7970 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7972 if (c
->kind
== ck_identity
&& c
->u
.expr
7973 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7979 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7980 class type or a pointer to class type. */
7983 build_trivial_dtor_call (tree instance
)
7985 gcc_assert (!is_dummy_object (instance
));
7987 if (!flag_lifetime_dse
)
7990 return fold_convert (void_type_node
, instance
);
7993 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
7995 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7997 instance
= cp_build_fold_indirect_ref (instance
);
8000 /* A trivial destructor should still clobber the object. */
8001 tree clobber
= build_clobber (TREE_TYPE (instance
));
8002 return build2 (MODIFY_EXPR
, void_type_node
,
8006 /* Subroutine of the various build_*_call functions. Overload resolution
8007 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
8008 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
8009 bitmask of various LOOKUP_* flags which apply to the call itself. */
8012 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
8015 const vec
<tree
, va_gc
> *args
= cand
->args
;
8016 tree first_arg
= cand
->first_arg
;
8017 conversion
**convs
= cand
->convs
;
8019 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
8024 unsigned int arg_index
= 0;
8028 bool already_used
= false;
8030 /* In a template, there is no need to perform all of the work that
8031 is normally done. We are only interested in the type of the call
8032 expression, i.e., the return type of the function. Any semantic
8033 errors will be deferred until the template is instantiated. */
8034 if (processing_template_decl
)
8038 const tree
*argarray
;
8041 if (undeduced_auto_decl (fn
))
8042 mark_used (fn
, complain
);
8044 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
8048 return_type
= TREE_TYPE (TREE_TYPE (fn
));
8049 nargs
= vec_safe_length (args
);
8050 if (first_arg
== NULL_TREE
)
8051 argarray
= args
->address ();
8059 alcarray
= XALLOCAVEC (tree
, nargs
);
8060 alcarray
[0] = build_this (first_arg
);
8061 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
8062 alcarray
[ix
+ 1] = arg
;
8063 argarray
= alcarray
;
8066 addr
= build_addr_func (fn
, complain
);
8067 if (addr
== error_mark_node
)
8068 return error_mark_node
;
8069 expr
= build_call_array_loc (input_location
, return_type
,
8070 addr
, nargs
, argarray
);
8071 if (TREE_THIS_VOLATILE (fn
) && cfun
)
8072 current_function_returns_abnormally
= 1;
8073 return convert_from_reference (expr
);
8076 /* Give any warnings we noticed during overload resolution. */
8077 if (cand
->warnings
&& (complain
& tf_warning
))
8079 struct candidate_warning
*w
;
8080 for (w
= cand
->warnings
; w
; w
= w
->next
)
8081 joust (cand
, w
->loser
, 1, complain
);
8084 /* Core issue 2327: P0135 doesn't say how to handle the case where the
8085 argument to the copy constructor ends up being a prvalue after
8086 conversion. Let's do the normal processing, but pretend we aren't
8087 actually using the copy constructor. */
8088 bool force_elide
= false;
8089 if (cxx_dialect
>= cxx17
8090 && cand
->num_convs
== 1
8091 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
8092 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8093 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8094 && conv_binds_ref_to_prvalue (convs
[0]))
8097 goto not_really_used
;
8100 /* OK, we're actually calling this inherited constructor; set its deletedness
8101 appropriately. We can get away with doing this here because calling is
8102 the only way to refer to a constructor. */
8103 if (DECL_INHERITED_CTOR (fn
))
8104 deduce_inheriting_ctor (fn
);
8106 /* Make =delete work with SFINAE. */
8107 if (DECL_DELETED_FN (fn
))
8109 if (complain
& tf_error
)
8111 return error_mark_node
;
8114 if (DECL_FUNCTION_MEMBER_P (fn
))
8117 /* If FN is a template function, two cases must be considered.
8122 template <class T> void f();
8124 template <class T> struct B {
8128 struct C : A, B<int> {
8130 using B<int>::g; // #2
8133 In case #1 where `A::f' is a member template, DECL_ACCESS is
8134 recorded in the primary template but not in its specialization.
8135 We check access of FN using its primary template.
8137 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
8138 because it is a member of class template B, DECL_ACCESS is
8139 recorded in the specialization `B<int>::g'. We cannot use its
8140 primary template because `B<T>::g' and `B<int>::g' may have
8141 different access. */
8142 if (DECL_TEMPLATE_INFO (fn
)
8143 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
8144 access_fn
= DECL_TI_TEMPLATE (fn
);
8147 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
8149 return error_mark_node
;
8152 /* If we're checking for implicit delete, don't bother with argument
8154 if (flags
& LOOKUP_SPECULATIVE
)
8156 if (cand
->viable
== 1)
8158 else if (!(complain
& tf_error
))
8159 /* Reject bad conversions now. */
8160 return error_mark_node
;
8161 /* else continue to get conversion error. */
8166 /* N3276 magic doesn't apply to nested calls. */
8167 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8168 complain
&= ~tf_decltype
;
8169 /* No-Cleanup doesn't apply to nested calls either. */
8170 tsubst_flags_t no_cleanup_complain
= complain
;
8171 complain
&= ~tf_no_cleanup
;
8173 /* Find maximum size of vector to hold converted arguments. */
8174 parmlen
= list_length (parm
);
8175 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8176 if (parmlen
> nargs
)
8178 argarray
= XALLOCAVEC (tree
, nargs
);
8180 /* The implicit parameters to a constructor are not considered by overload
8181 resolution, and must be of the proper type. */
8182 if (DECL_CONSTRUCTOR_P (fn
))
8185 if (first_arg
!= NULL_TREE
)
8187 object_arg
= first_arg
;
8188 first_arg
= NULL_TREE
;
8192 object_arg
= (*args
)[arg_index
];
8195 argarray
[j
++] = build_this (object_arg
);
8196 parm
= TREE_CHAIN (parm
);
8197 /* We should never try to call the abstract constructor. */
8198 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8200 if (DECL_HAS_VTT_PARM_P (fn
))
8202 argarray
[j
++] = (*args
)[arg_index
];
8204 parm
= TREE_CHAIN (parm
);
8207 if (flags
& LOOKUP_PREFER_RVALUE
)
8209 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8210 the first parameter of the selected constructor is not an rvalue
8211 reference to the object's type (possibly cv-qualified)...." */
8212 gcc_assert (!(complain
& tf_error
));
8213 tree ptype
= convs
[0]->type
;
8214 if (!TYPE_REF_P (ptype
)
8215 || !TYPE_REF_IS_RVALUE (ptype
)
8216 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8217 return error_mark_node
;
8220 /* Bypass access control for 'this' parameter. */
8221 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8223 tree parmtype
= TREE_VALUE (parm
);
8224 tree arg
= build_this (first_arg
!= NULL_TREE
8226 : (*args
)[arg_index
]);
8227 tree argtype
= TREE_TYPE (arg
);
8231 if (arg
== error_mark_node
)
8232 return error_mark_node
;
8234 if (convs
[i
]->bad_p
)
8236 if (complain
& tf_error
)
8238 auto_diagnostic_group d
;
8239 if (permerror (input_location
, "passing %qT as %<this%> "
8240 "argument discards qualifiers",
8241 TREE_TYPE (argtype
)))
8242 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8245 return error_mark_node
;
8248 /* See if the function member or the whole class type is declared
8249 final and the call can be devirtualized. */
8250 if (DECL_FINAL_P (fn
)
8251 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
8252 flags
|= LOOKUP_NONVIRTUAL
;
8254 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8255 X is called for an object that is not of type X, or of a type
8256 derived from X, the behavior is undefined.
8258 So we can assume that anything passed as 'this' is non-null, and
8259 optimize accordingly. */
8260 gcc_assert (TYPE_PTR_P (parmtype
));
8261 /* Convert to the base in which the function was declared. */
8262 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8263 converted_arg
= build_base_path (PLUS_EXPR
,
8265 cand
->conversion_path
,
8267 /* Check that the base class is accessible. */
8268 if (!accessible_base_p (TREE_TYPE (argtype
),
8269 BINFO_TYPE (cand
->conversion_path
), true))
8271 if (complain
& tf_error
)
8272 error ("%qT is not an accessible base of %qT",
8273 BINFO_TYPE (cand
->conversion_path
),
8274 TREE_TYPE (argtype
));
8276 return error_mark_node
;
8278 /* If fn was found by a using declaration, the conversion path
8279 will be to the derived class, not the base declaring fn. We
8280 must convert from derived to base. */
8281 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8282 TREE_TYPE (parmtype
), ba_unique
,
8284 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8285 base_binfo
, 1, complain
);
8287 argarray
[j
++] = converted_arg
;
8288 parm
= TREE_CHAIN (parm
);
8289 if (first_arg
!= NULL_TREE
)
8290 first_arg
= NULL_TREE
;
8297 gcc_assert (first_arg
== NULL_TREE
);
8298 for (; arg_index
< vec_safe_length (args
) && parm
;
8299 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8301 tree type
= TREE_VALUE (parm
);
8302 tree arg
= (*args
)[arg_index
];
8303 bool conversion_warning
= true;
8307 /* If the argument is NULL and used to (implicitly) instantiate a
8308 template function (and bind one of the template arguments to
8309 the type of 'long int'), we don't want to warn about passing NULL
8310 to non-pointer argument.
8311 For example, if we have this template function:
8313 template<typename T> void func(T x) {}
8315 we want to warn (when -Wconversion is enabled) in this case:
8321 but not in this case:
8327 if (null_node_p (arg
)
8328 && DECL_TEMPLATE_INFO (fn
)
8329 && cand
->template_decl
8330 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8331 conversion_warning
= false;
8333 /* Warn about initializer_list deduction that isn't currently in the
8335 if (cxx_dialect
> cxx98
8336 && flag_deduce_init_list
8337 && cand
->template_decl
8338 && is_std_init_list (non_reference (type
))
8339 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
8341 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
8342 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
8343 tree patparm
= get_pattern_parm (realparm
, tmpl
);
8344 tree pattype
= TREE_TYPE (patparm
);
8345 if (PACK_EXPANSION_P (pattype
))
8346 pattype
= PACK_EXPANSION_PATTERN (pattype
);
8347 pattype
= non_reference (pattype
);
8349 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
8350 && (cand
->explicit_targs
== NULL_TREE
8351 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
8352 <= TEMPLATE_TYPE_IDX (pattype
))))
8354 pedwarn (input_location
, 0, "deducing %qT as %qT",
8355 non_reference (TREE_TYPE (patparm
)),
8356 non_reference (type
));
8357 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
8358 " in call to %qD", cand
->fn
);
8359 pedwarn (input_location
, 0,
8360 " (you can disable this with "
8361 "%<-fno-deduce-init-list%>)");
8365 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8366 knows not to allow any more UDCs. This needs to happen after we
8367 process cand->warnings. */
8368 if (flags
& LOOKUP_NO_CONVERSION
)
8369 conv
->user_conv_p
= true;
8371 tsubst_flags_t arg_complain
= complain
;
8372 if (!conversion_warning
)
8373 arg_complain
&= ~tf_warning
;
8375 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8377 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8379 if (val
== error_mark_node
)
8380 return error_mark_node
;
8382 argarray
[j
++] = val
;
8385 /* Default arguments */
8386 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8388 if (TREE_VALUE (parm
) == error_mark_node
)
8389 return error_mark_node
;
8390 val
= convert_default_arg (TREE_VALUE (parm
),
8391 TREE_PURPOSE (parm
),
8394 if (val
== error_mark_node
)
8395 return error_mark_node
;
8396 argarray
[j
++] = val
;
8400 int magic
= magic_varargs_p (fn
);
8401 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8403 tree a
= (*args
)[arg_index
];
8404 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8406 /* Do no conversions for certain magic varargs. */
8407 a
= mark_type_use (a
);
8408 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8409 return error_mark_node
;
8411 else if (magic
!= 0)
8412 /* For other magic varargs only do decay_conversion. */
8413 a
= decay_conversion (a
, complain
);
8414 else if (DECL_CONSTRUCTOR_P (fn
)
8415 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8418 /* Avoid infinite recursion trying to call A(...). */
8419 if (complain
& tf_error
)
8420 /* Try to call the actual copy constructor for a good error. */
8421 call_copy_ctor (a
, complain
);
8422 return error_mark_node
;
8425 a
= convert_arg_to_ellipsis (a
, complain
);
8426 if (a
== error_mark_node
)
8427 return error_mark_node
;
8431 gcc_assert (j
<= nargs
);
8434 /* Avoid to do argument-transformation, if warnings for format, and for
8435 nonnull are disabled. Just in case that at least one of them is active
8436 the check_function_arguments function might warn about something. */
8438 bool warned_p
= false;
8441 || warn_suggest_attribute_format
8444 tree
*fargs
= (!nargs
? argarray
8445 : (tree
*) alloca (nargs
* sizeof (tree
)));
8446 for (j
= 0; j
< nargs
; j
++)
8448 /* For -Wformat undo the implicit passing by hidden reference
8449 done by convert_arg_to_ellipsis. */
8450 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8451 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8452 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8454 fargs
[j
] = argarray
[j
];
8457 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8458 nargs
, fargs
, NULL
);
8461 if (DECL_INHERITED_CTOR (fn
))
8463 /* Check for passing ellipsis arguments to an inherited constructor. We
8464 could handle this by open-coding the inherited constructor rather than
8465 defining it, but let's not bother now. */
8466 if (!cp_unevaluated_operand
8468 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8470 if (complain
& tf_error
)
8472 sorry ("passing arguments to ellipsis of inherited constructor "
8474 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8476 return error_mark_node
;
8479 /* A base constructor inheriting from a virtual base doesn't get the
8480 inherited arguments, just this and __vtt. */
8481 if (ctor_omit_inherited_parms (fn
))
8485 /* Avoid actually calling copy constructors and copy assignment operators,
8488 if (! flag_elide_constructors
&& !force_elide
)
8489 /* Do things the hard way. */;
8490 else if (cand
->num_convs
== 1
8491 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8492 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8493 /* It's unsafe to elide the constructor when handling
8494 a noexcept-expression, it may evaluate to the wrong
8495 value (c++/53025). */
8496 && (force_elide
|| cp_noexcept_operand
== 0))
8499 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8501 bool trivial
= trivial_fn_p (fn
);
8503 /* Pull out the real argument, disregarding const-correctness. */
8505 /* Strip the reference binding for the constructor parameter. */
8506 if (CONVERT_EXPR_P (targ
)
8507 && TYPE_REF_P (TREE_TYPE (targ
)))
8508 targ
= TREE_OPERAND (targ
, 0);
8509 /* But don't strip any other reference bindings; binding a temporary to a
8510 reference prevents copy elision. */
8511 while ((CONVERT_EXPR_P (targ
)
8512 && !TYPE_REF_P (TREE_TYPE (targ
)))
8513 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8514 targ
= TREE_OPERAND (targ
, 0);
8515 if (TREE_CODE (targ
) == ADDR_EXPR
)
8517 targ
= TREE_OPERAND (targ
, 0);
8518 if (!same_type_ignoring_top_level_qualifiers_p
8519 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8528 arg
= cp_build_fold_indirect_ref (arg
);
8530 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8532 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8533 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8535 /* It's from binding the ref parm to a packed field. */
8536 || convs
[0]->need_temporary_p
8538 /* See unsafe_copy_elision_p. */
8539 || DECL_BASE_CONSTRUCTOR_P (fn
));
8542 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8543 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8545 /* [class.copy]: the copy constructor is implicitly defined even if the
8546 implementation elided its use. But don't warn about deprecation when
8547 eliding a temporary, as then no copy is actually performed. */
8548 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8550 /* The language says this isn't called. */;
8553 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8554 return error_mark_node
;
8555 already_used
= true;
8558 cp_warn_deprecated_use (fn
, complain
);
8560 /* If we're creating a temp and we already have one, don't create a
8561 new one. If we're not creating a temp but we get one, use
8562 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8563 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8564 temp or an INIT_EXPR otherwise. */
8565 if (is_dummy_object (fa
))
8567 if (TREE_CODE (arg
) == TARGET_EXPR
)
8570 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8572 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8575 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8577 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8581 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8582 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8583 && trivial_fn_p (fn
))
8585 tree to
= cp_stabilize_reference
8586 (cp_build_fold_indirect_ref (argarray
[0]));
8587 tree type
= TREE_TYPE (to
);
8588 tree as_base
= CLASSTYPE_AS_BASE (type
);
8589 tree arg
= argarray
[1];
8590 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
8592 if (is_really_empty_class (type
, /*ignore_vptr*/true))
8594 /* Avoid copying empty classes. */
8595 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8596 TREE_NO_WARNING (val
) = 1;
8598 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8600 if (is_std_init_list (type
)
8601 && conv_binds_ref_to_prvalue (convs
[1]))
8602 warning_at (loc
, OPT_Winit_list_lifetime
,
8603 "assignment from temporary initializer_list does not "
8604 "extend the lifetime of the underlying array");
8605 arg
= cp_build_fold_indirect_ref (arg
);
8606 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8610 /* We must only copy the non-tail padding parts. */
8612 tree array_type
, alias_set
;
8614 arg2
= TYPE_SIZE_UNIT (as_base
);
8615 arg0
= cp_build_addr_expr (to
, complain
);
8617 array_type
= build_array_type (unsigned_char_type_node
,
8619 (size_binop (MINUS_EXPR
,
8620 arg2
, size_int (1))));
8621 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8622 t
= build2 (MODIFY_EXPR
, void_type_node
,
8623 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8624 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8625 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8626 TREE_NO_WARNING (val
) = 1;
8629 cp_warn_deprecated_use (fn
, complain
);
8633 else if (trivial_fn_p (fn
))
8635 if (DECL_DESTRUCTOR_P (fn
))
8636 return build_trivial_dtor_call (argarray
[0]);
8637 else if (default_ctor_p (fn
))
8639 if (is_dummy_object (argarray
[0]))
8640 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8641 no_cleanup_complain
);
8643 return cp_build_fold_indirect_ref (argarray
[0]);
8647 gcc_assert (!force_elide
);
8650 && !mark_used (fn
, complain
))
8651 return error_mark_node
;
8653 /* Warn if the built-in writes to an object of a non-trivial type. */
8654 if (warn_class_memaccess
8655 && vec_safe_length (args
) >= 2
8656 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8657 maybe_warn_class_memaccess (input_location
, fn
, args
);
8659 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8662 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8664 ba_any
, NULL
, complain
);
8665 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8667 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8669 if (TREE_SIDE_EFFECTS (argarray
[0]))
8670 argarray
[0] = save_expr (argarray
[0]);
8671 t
= build_pointer_type (TREE_TYPE (fn
));
8672 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8677 fn
= build_addr_func (fn
, complain
);
8678 if (fn
== error_mark_node
)
8679 return error_mark_node
;
8682 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8683 if (call
== error_mark_node
)
8685 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8687 tree c
= extract_call_expr (call
);
8688 /* build_new_op_1 will clear this when appropriate. */
8689 CALL_EXPR_ORDERED_ARGS (c
) = true;
8693 tree c
= extract_call_expr (call
);
8694 if (TREE_CODE (c
) == CALL_EXPR
)
8695 TREE_NO_WARNING (c
) = 1;
8703 /* Return the DECL of the first non-static subobject of class TYPE
8704 that satisfies the predicate PRED or null if none can be found. */
8706 template <class Predicate
>
8708 first_non_static_field (tree type
, Predicate pred
)
8710 if (!type
|| !CLASS_TYPE_P (type
))
8713 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8715 if (TREE_CODE (field
) != FIELD_DECL
)
8717 if (TREE_STATIC (field
))
8725 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8726 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8728 tree base
= TREE_TYPE (base_binfo
);
8731 if (tree field
= first_non_static_field (base
, pred
))
8738 struct NonPublicField
8740 bool operator() (const_tree t
)
8742 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8746 /* Return the DECL of the first non-public subobject of class TYPE
8747 or null if none can be found. */
8750 first_non_public_field (tree type
)
8752 return first_non_static_field (type
, NonPublicField ());
8755 struct NonTrivialField
8757 bool operator() (const_tree t
)
8759 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8763 /* Return the DECL of the first non-trivial subobject of class TYPE
8764 or null if none can be found. */
8767 first_non_trivial_field (tree type
)
8769 return first_non_static_field (type
, NonTrivialField ());
8772 } /* unnamed namespace */
8774 /* Return true if all copy and move assignment operator overloads for
8775 class TYPE are trivial and at least one of them is not deleted and,
8776 when ACCESS is set, accessible. Return false otherwise. Set
8777 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8778 copy or move assignment. */
8781 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8783 tree fns
= get_class_binding (type
, assign_op_identifier
);
8784 bool all_trivial
= true;
8786 /* Iterate over overloads of the assignment operator, checking
8787 accessible copy assignments for triviality. */
8789 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8793 /* Skip operators that aren't copy assignments. */
8797 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8798 || accessible_p (TYPE_BINFO (type
), f
, true));
8800 /* Skip template assignment operators and deleted functions. */
8801 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8807 if (!accessible
|| !trivial_fn_p (f
))
8808 all_trivial
= false;
8810 /* Break early when both properties have been determined. */
8811 if (*hasassign
&& !all_trivial
)
8815 /* Return true if they're all trivial and one of the expressions
8816 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8817 tree ref
= cp_build_reference_type (type
, false);
8819 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8820 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8823 /* Return true if all copy and move ctor overloads for class TYPE are
8824 trivial and at least one of them is not deleted and, when ACCESS is
8825 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8826 to true when the TYPE has a (not necessarily trivial) default and copy
8827 (or move) ctor, respectively. */
8830 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8832 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8833 bool all_trivial
= true;
8835 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8839 /* Skip template constructors. */
8840 if (TREE_CODE (f
) != FUNCTION_DECL
)
8843 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8845 /* Skip ctors other than default, copy, and move. */
8846 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8849 if (DECL_DELETED_FN (f
))
8852 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8853 || accessible_p (TYPE_BINFO (type
), f
, true));
8856 hasctor
[cpy_or_move_ctor_p
] = true;
8858 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8859 all_trivial
= false;
8861 /* Break early when both properties have been determined. */
8862 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8869 /* Issue a warning on a call to the built-in function FNDECL if it is
8870 a raw memory write whose destination is not an object of (something
8871 like) trivial or standard layout type with a non-deleted assignment
8872 and copy ctor. Detects const correctness violations, corrupting
8873 references, virtual table pointers, and bypassing non-trivial
8877 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8878 const vec
<tree
, va_gc
> *args
)
8880 /* Except for bcopy where it's second, the destination pointer is
8881 the first argument for all functions handled here. Compute
8882 the index of the destination and source arguments. */
8883 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8884 unsigned srcidx
= !dstidx
;
8886 tree dest
= (*args
)[dstidx
];
8887 if (!TREE_TYPE (dest
) || !INDIRECT_TYPE_P (TREE_TYPE (dest
)))
8890 tree srctype
= NULL_TREE
;
8892 /* Determine the type of the pointed-to object and whether it's
8893 a complete class type. */
8894 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8896 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8899 /* Check to see if the raw memory call is made by a non-static member
8900 function with THIS as the destination argument for the destination
8901 type. If so, and if the class has no non-trivial bases or members,
8902 be more permissive. */
8903 if (current_function_decl
8904 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8905 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8907 tree ctx
= DECL_CONTEXT (current_function_decl
);
8908 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8909 tree binfo
= TYPE_BINFO (ctx
);
8912 && !BINFO_VTABLE (binfo
)
8913 && !first_non_trivial_field (desttype
))
8917 /* True if the class is trivial. */
8918 bool trivial
= trivial_type_p (desttype
);
8920 /* Set to true if DESTYPE has an accessible copy assignment. */
8921 bool hasassign
= false;
8922 /* True if all of the class' overloaded copy assignment operators
8923 are all trivial (and not deleted) and at least one of them is
8925 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8927 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8929 bool hasctors
[2] = { false, false };
8931 /* True if all of the class' overloaded copy constructors are all
8932 trivial (and not deleted) and at least one of them is accessible. */
8933 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8935 /* Set FLD to the first private/protected member of the class. */
8936 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8938 /* The warning format string. */
8939 const char *warnfmt
= NULL
;
8940 /* A suggested alternative to offer instead of the raw memory call.
8941 Empty string when none can be come up with. */
8942 const char *suggest
= "";
8943 bool warned
= false;
8945 switch (DECL_FUNCTION_CODE (fndecl
))
8947 case BUILT_IN_MEMSET
:
8948 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8950 /* Diagnose setting non-copy-assignable or non-trivial types,
8951 or types with a private member, to (potentially) non-zero
8952 bytes. Since the value of the bytes being written is unknown,
8953 suggest using assignment instead (if one exists). Also warn
8954 for writes into objects for which zero-initialization doesn't
8955 mean all bits clear (pointer-to-member data, where null is all
8956 bits set). Since the value being written is (most likely)
8957 non-zero, simply suggest assignment (but not copy assignment). */
8958 suggest
= "; use assignment instead";
8960 warnfmt
= G_("%qD writing to an object of type %#qT with "
8961 "no trivial copy-assignment");
8963 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8966 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8967 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8968 "%qD writing to an object of type %#qT with "
8970 fndecl
, desttype
, access
, fld
);
8972 else if (!zero_init_p (desttype
))
8973 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8974 "a pointer to data member%s");
8980 case BUILT_IN_BZERO
:
8981 /* Similarly to the above, diagnose clearing non-trivial or non-
8982 standard layout objects, or objects of types with no assignmenmt.
8983 Since the value being written is known to be zero, suggest either
8984 copy assignment, copy ctor, or default ctor as an alternative,
8985 depending on what's available. */
8987 if (hasassign
&& hasctors
[0])
8988 suggest
= G_("; use assignment or value-initialization instead");
8990 suggest
= G_("; use assignment instead");
8991 else if (hasctors
[0])
8992 suggest
= G_("; use value-initialization instead");
8995 warnfmt
= G_("%qD clearing an object of type %#qT with "
8996 "no trivial copy-assignment%s");
8998 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8999 else if (!zero_init_p (desttype
))
9000 warnfmt
= G_("%qD clearing an object of type %#qT containing "
9001 "a pointer-to-member%s");
9004 case BUILT_IN_BCOPY
:
9005 case BUILT_IN_MEMCPY
:
9006 case BUILT_IN_MEMMOVE
:
9007 case BUILT_IN_MEMPCPY
:
9008 /* Determine the type of the source object. */
9009 srctype
= TREE_TYPE ((*args
)[srcidx
]);
9010 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
9011 srctype
= void_type_node
;
9013 srctype
= TREE_TYPE (srctype
);
9015 /* Since it's impossible to determine wheter the byte copy is
9016 being used in place of assignment to an existing object or
9017 as a substitute for initialization, assume it's the former.
9018 Determine the best alternative to use instead depending on
9019 what's not deleted. */
9020 if (hasassign
&& hasctors
[1])
9021 suggest
= G_("; use copy-assignment or copy-initialization instead");
9023 suggest
= G_("; use copy-assignment instead");
9024 else if (hasctors
[1])
9025 suggest
= G_("; use copy-initialization instead");
9028 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
9029 "copy-assignment%s");
9030 else if (!trivially_copyable_p (desttype
))
9031 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
9034 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
9037 && !VOID_TYPE_P (srctype
)
9038 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9039 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9042 /* Warn when copying into a non-trivial object from an object
9043 of a different type other than void or char. */
9044 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9045 "%qD copying an object of non-trivial type "
9046 "%#qT from an array of %#qT",
9047 fndecl
, desttype
, srctype
);
9050 && !VOID_TYPE_P (srctype
)
9051 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9052 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9055 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
9056 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9057 "%qD copying an object of type %#qT with "
9058 "%qs member %qD from an array of %#qT; use "
9059 "assignment or copy-initialization instead",
9060 fndecl
, desttype
, access
, fld
, srctype
);
9062 else if (!trivial
&& vec_safe_length (args
) > 2)
9064 tree sz
= maybe_constant_value ((*args
)[2]);
9065 if (!tree_fits_uhwi_p (sz
))
9068 /* Finally, warn on partial copies. */
9069 unsigned HOST_WIDE_INT typesize
9070 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
9071 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
9072 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9073 (typesize
- partial
> 1
9074 ? G_("%qD writing to an object of "
9075 "a non-trivial type %#qT leaves %wu "
9077 : G_("%qD writing to an object of "
9078 "a non-trivial type %#qT leaves %wu "
9080 fndecl
, desttype
, typesize
- partial
);
9084 case BUILT_IN_REALLOC
:
9086 if (!trivially_copyable_p (desttype
))
9087 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
9088 "%#qT; use %<new%> and %<delete%> instead");
9090 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
9091 "constructor; use %<new%> and %<delete%> instead");
9092 else if (!get_dtor (desttype
, tf_none
))
9093 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
9097 tree sz
= maybe_constant_value ((*args
)[1]);
9098 if (TREE_CODE (sz
) == INTEGER_CST
9099 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
9100 /* Finally, warn on reallocation into insufficient space. */
9101 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9102 "%qD moving an object of non-trivial type "
9103 "%#qT and size %E into a region of size %E",
9104 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
9116 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9117 warnfmt
, fndecl
, desttype
, suggest
);
9119 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9120 warnfmt
, fndecl
, desttype
);
9124 inform (location_of (desttype
), "%#qT declared here", desttype
);
9127 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
9128 This function performs no overload resolution, conversion, or other
9129 high-level operations. */
9132 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
9133 tsubst_flags_t complain
)
9137 /* Remember roughly where this call is. */
9138 location_t loc
= cp_expr_loc_or_loc (fn
, input_location
);
9139 fn
= build_call_a (fn
, nargs
, argarray
);
9140 SET_EXPR_LOCATION (fn
, loc
);
9142 fndecl
= get_callee_fndecl (fn
);
9144 /* Check that arguments to builtin functions match the expectations. */
9146 && !processing_template_decl
9147 && fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
9151 /* We need to take care that values to BUILT_IN_NORMAL
9153 for (i
= 0; i
< nargs
; i
++)
9154 argarray
[i
] = maybe_constant_value (argarray
[i
]);
9156 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
9158 return error_mark_node
;
9161 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9164 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9165 function call is either the operand of a decltype-specifier or the
9166 right operand of a comma operator that is the operand of a
9167 decltype-specifier, a temporary object is not introduced for the
9168 prvalue. The type of the prvalue may be incomplete. */
9169 if (!(complain
& tf_decltype
))
9171 fn
= require_complete_type_sfinae (fn
, complain
);
9172 if (fn
== error_mark_node
)
9173 return error_mark_node
;
9175 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9177 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9178 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9181 return convert_from_reference (fn
);
9184 /* Returns the value to use for the in-charge parameter when making a
9185 call to a function with the indicated NAME.
9187 FIXME:Can't we find a neater way to do this mapping? */
9190 in_charge_arg_for_name (tree name
)
9192 if (IDENTIFIER_CTOR_P (name
))
9194 if (name
== complete_ctor_identifier
)
9195 return integer_one_node
;
9196 gcc_checking_assert (name
== base_ctor_identifier
);
9200 if (name
== complete_dtor_identifier
)
9201 return integer_two_node
;
9202 else if (name
== deleting_dtor_identifier
)
9203 return integer_three_node
;
9204 gcc_checking_assert (name
== base_dtor_identifier
);
9207 return integer_zero_node
;
9210 /* We've built up a constructor call RET. Complain if it delegates to the
9211 constructor we're currently compiling. */
9214 check_self_delegation (tree ret
)
9216 if (TREE_CODE (ret
) == TARGET_EXPR
)
9217 ret
= TARGET_EXPR_INITIAL (ret
);
9218 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9219 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9220 error ("constructor delegates to itself");
9223 /* Build a call to a constructor, destructor, or an assignment
9224 operator for INSTANCE, an expression with class type. NAME
9225 indicates the special member function to call; *ARGS are the
9226 arguments. ARGS may be NULL. This may change ARGS. BINFO
9227 indicates the base of INSTANCE that is to be passed as the `this'
9228 parameter to the member function called.
9230 FLAGS are the LOOKUP_* flags to use when processing the call.
9232 If NAME indicates a complete object constructor, INSTANCE may be
9233 NULL_TREE. In this case, the caller will call build_cplus_new to
9234 store the newly constructed object into a VAR_DECL. */
9237 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9238 tree binfo
, int flags
, tsubst_flags_t complain
)
9241 /* The type of the subobject to be constructed or destroyed. */
9243 vec
<tree
, va_gc
> *allocated
= NULL
;
9246 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9248 if (error_operand_p (instance
))
9249 return error_mark_node
;
9251 if (IDENTIFIER_DTOR_P (name
))
9253 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9254 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9255 /* Shortcut to avoid lazy destructor declaration. */
9256 return build_trivial_dtor_call (instance
);
9261 /* Resolve the name. */
9262 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9263 return error_mark_node
;
9265 binfo
= TYPE_BINFO (binfo
);
9268 gcc_assert (binfo
!= NULL_TREE
);
9270 class_type
= BINFO_TYPE (binfo
);
9272 /* Handle the special case where INSTANCE is NULL_TREE. */
9273 if (name
== complete_ctor_identifier
&& !instance
)
9274 instance
= build_dummy_object (class_type
);
9277 /* Convert to the base class, if necessary. */
9278 if (!same_type_ignoring_top_level_qualifiers_p
9279 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9281 if (IDENTIFIER_CDTOR_P (name
))
9282 /* For constructors and destructors, either the base is
9283 non-virtual, or it is virtual but we are doing the
9284 conversion from a constructor or destructor for the
9285 complete object. In either case, we can convert
9287 instance
= convert_to_base_statically (instance
, binfo
);
9290 /* However, for assignment operators, we must convert
9291 dynamically if the base is virtual. */
9292 gcc_checking_assert (name
== assign_op_identifier
);
9293 instance
= build_base_path (PLUS_EXPR
, instance
,
9294 binfo
, /*nonnull=*/1, complain
);
9299 gcc_assert (instance
!= NULL_TREE
);
9301 /* In C++17, "If the initializer expression is a prvalue and the
9302 cv-unqualified version of the source type is the same class as the class
9303 of the destination, the initializer expression is used to initialize the
9304 destination object." Handle that here to avoid doing overload
9306 if (cxx_dialect
>= cxx17
9307 && args
&& vec_safe_length (*args
) == 1
9308 && name
== complete_ctor_identifier
)
9310 tree arg
= (**args
)[0];
9312 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9313 && !TYPE_HAS_LIST_CTOR (class_type
)
9314 && CONSTRUCTOR_NELTS (arg
) == 1)
9315 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9317 if ((TREE_CODE (arg
) == TARGET_EXPR
9318 || TREE_CODE (arg
) == CONSTRUCTOR
)
9319 && (same_type_ignoring_top_level_qualifiers_p
9320 (class_type
, TREE_TYPE (arg
))))
9322 if (is_dummy_object (instance
))
9324 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9325 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9327 if ((complain
& tf_error
)
9328 && (flags
& LOOKUP_DELEGATING_CONS
))
9329 check_self_delegation (arg
);
9330 /* Avoid change of behavior on Wunused-var-2.C. */
9331 instance
= mark_lvalue_use (instance
);
9332 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9336 fns
= lookup_fnfields (binfo
, name
, 1);
9338 /* When making a call to a constructor or destructor for a subobject
9339 that uses virtual base classes, pass down a pointer to a VTT for
9341 if ((name
== base_ctor_identifier
9342 || name
== base_dtor_identifier
)
9343 && CLASSTYPE_VBASECLASSES (class_type
))
9348 /* If the current function is a complete object constructor
9349 or destructor, then we fetch the VTT directly.
9350 Otherwise, we look it up using the VTT we were given. */
9351 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9352 vtt
= decay_conversion (vtt
, complain
);
9353 if (vtt
== error_mark_node
)
9354 return error_mark_node
;
9355 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9356 if (BINFO_SUBVTT_INDEX (binfo
))
9357 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9363 allocated
= make_tree_vector ();
9367 vec_safe_insert (*args
, 0, sub_vtt
);
9370 ret
= build_new_method_call (instance
, fns
, args
,
9371 TYPE_BINFO (BINFO_TYPE (binfo
)),
9375 if (allocated
!= NULL
)
9376 release_tree_vector (allocated
);
9378 if ((complain
& tf_error
)
9379 && (flags
& LOOKUP_DELEGATING_CONS
)
9380 && name
== complete_ctor_identifier
)
9381 check_self_delegation (ret
);
9386 /* Return the NAME, as a C string. The NAME indicates a function that
9387 is a member of TYPE. *FREE_P is set to true if the caller must
9388 free the memory returned.
9390 Rather than go through all of this, we should simply set the names
9391 of constructors and destructors appropriately, and dispense with
9392 ctor_identifier, dtor_identifier, etc. */
9395 name_as_c_string (tree name
, tree type
, bool *free_p
)
9397 const char *pretty_name
;
9399 /* Assume that we will not allocate memory. */
9401 /* Constructors and destructors are special. */
9402 if (IDENTIFIER_CDTOR_P (name
))
9405 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9406 /* For a destructor, add the '~'. */
9407 if (IDENTIFIER_DTOR_P (name
))
9409 pretty_name
= concat ("~", pretty_name
, NULL
);
9410 /* Remember that we need to free the memory allocated. */
9414 else if (IDENTIFIER_CONV_OP_P (name
))
9416 pretty_name
= concat ("operator ",
9417 type_as_string_translate (TREE_TYPE (name
),
9418 TFF_PLAIN_IDENTIFIER
),
9420 /* Remember that we need to free the memory allocated. */
9424 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9426 return CONST_CAST (char *, pretty_name
);
9429 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9432 static z_candidate
*
9433 single_z_candidate (z_candidate
*candidates
)
9435 if (candidates
== NULL
)
9438 if (candidates
->next
)
9444 /* If CANDIDATE is invalid due to a bad argument type, return the
9445 pertinent conversion_info.
9447 Otherwise, return NULL. */
9449 static const conversion_info
*
9450 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9452 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9453 rejection_reason
*r
= candidate
->reason
;
9463 case rr_arg_conversion
:
9464 return &r
->u
.conversion
;
9466 case rr_bad_arg_conversion
:
9467 return &r
->u
.bad_conversion
;
9471 /* Issue an error and note complaining about a bad argument type at a
9472 callsite with a single candidate FNDECL.
9474 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9475 case input_location is used).
9476 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9477 the formal parameter. */
9480 complain_about_bad_argument (location_t arg_loc
,
9481 tree from_type
, tree to_type
,
9482 tree fndecl
, int parmnum
)
9484 auto_diagnostic_group d
;
9485 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9486 range_label
*label
= &rhs_label
;
9487 if (arg_loc
== UNKNOWN_LOCATION
)
9489 arg_loc
= input_location
;
9492 gcc_rich_location
richloc (arg_loc
, label
);
9494 "cannot convert %qH to %qI",
9495 from_type
, to_type
);
9496 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9500 /* Subroutine of build_new_method_call_1, for where there are no viable
9501 candidates for the call. */
9504 complain_about_no_candidates_for_method_call (tree instance
,
9505 z_candidate
*candidates
,
9506 tree explicit_targs
,
9508 tree optype
, tree name
,
9509 bool skip_first_for_error
,
9510 vec
<tree
, va_gc
> *user_args
)
9512 auto_diagnostic_group d
;
9513 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9514 cxx_incomplete_type_error (instance
, basetype
);
9516 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9517 basetype
, optype
, build_tree_list_vec (user_args
),
9518 TREE_TYPE (instance
));
9521 /* Special-case for when there's a single candidate that's failing
9522 due to a bad argument type. */
9523 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9524 if (const conversion_info
*conv
9525 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9527 complain_about_bad_argument (conv
->loc
,
9528 conv
->from
, conv
->to_type
,
9529 candidate
->fn
, conv
->n_arg
);
9533 tree arglist
= build_tree_list_vec (user_args
);
9534 tree errname
= name
;
9535 bool twiddle
= false;
9536 if (IDENTIFIER_CDTOR_P (errname
))
9538 twiddle
= IDENTIFIER_DTOR_P (errname
);
9539 errname
= constructor_name (basetype
);
9542 errname
= lookup_template_function (errname
, explicit_targs
);
9543 if (skip_first_for_error
)
9544 arglist
= TREE_CHAIN (arglist
);
9545 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9546 basetype
, &"~"[!twiddle
], errname
, arglist
,
9547 TREE_TYPE (instance
));
9549 print_z_candidates (location_of (name
), candidates
);
9552 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9553 be set, upon return, to the function called. ARGS may be NULL.
9554 This may change ARGS. */
9557 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9558 tree conversion_path
, int flags
,
9559 tree
*fn_p
, tsubst_flags_t complain
)
9561 struct z_candidate
*candidates
= 0, *cand
;
9562 tree explicit_targs
= NULL_TREE
;
9563 tree basetype
= NULL_TREE
;
9564 tree access_binfo
, binfo
;
9566 tree first_mem_arg
= NULL_TREE
;
9568 bool skip_first_for_error
;
9569 vec
<tree
, va_gc
> *user_args
;
9572 int template_only
= 0;
9576 vec
<tree
, va_gc
> *orig_args
= NULL
;
9579 gcc_assert (instance
!= NULL_TREE
);
9581 /* We don't know what function we're going to call, yet. */
9585 if (error_operand_p (instance
)
9586 || !fns
|| error_operand_p (fns
))
9587 return error_mark_node
;
9589 if (!BASELINK_P (fns
))
9591 if (complain
& tf_error
)
9592 error ("call to non-function %qD", fns
);
9593 return error_mark_node
;
9596 orig_instance
= instance
;
9599 /* Dismantle the baselink to collect all the information we need. */
9600 if (!conversion_path
)
9601 conversion_path
= BASELINK_BINFO (fns
);
9602 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9603 binfo
= BASELINK_BINFO (fns
);
9604 optype
= BASELINK_OPTYPE (fns
);
9605 fns
= BASELINK_FUNCTIONS (fns
);
9606 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9608 explicit_targs
= TREE_OPERAND (fns
, 1);
9609 fns
= TREE_OPERAND (fns
, 0);
9612 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
9613 || TREE_CODE (fns
) == TEMPLATE_DECL
9614 || TREE_CODE (fns
) == OVERLOAD
);
9615 fn
= OVL_FIRST (fns
);
9616 name
= DECL_NAME (fn
);
9618 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9619 gcc_assert (CLASS_TYPE_P (basetype
));
9621 user_args
= args
== NULL
? NULL
: *args
;
9622 /* Under DR 147 A::A() is an invalid constructor call,
9623 not a functional cast. */
9624 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9626 if (! (complain
& tf_error
))
9627 return error_mark_node
;
9629 basetype
= DECL_CONTEXT (fn
);
9630 name
= constructor_name (basetype
);
9631 auto_diagnostic_group d
;
9632 if (permerror (input_location
,
9633 "cannot call constructor %<%T::%D%> directly",
9635 inform (input_location
, "for a function-style cast, remove the "
9636 "redundant %<::%D%>", name
);
9637 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9642 if (processing_template_decl
)
9644 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9645 instance
= build_non_dependent_expr (instance
);
9647 make_args_non_dependent (*args
);
9650 /* Process the argument list. */
9651 if (args
!= NULL
&& *args
!= NULL
)
9653 *args
= resolve_args (*args
, complain
);
9655 return error_mark_node
;
9659 /* Consider the object argument to be used even if we end up selecting a
9660 static member function. */
9661 instance
= mark_type_use (instance
);
9663 /* Figure out whether to skip the first argument for the error
9664 message we will display to users if an error occurs. We don't
9665 want to display any compiler-generated arguments. The "this"
9666 pointer hasn't been added yet. However, we must remove the VTT
9667 pointer if this is a call to a base-class constructor or
9669 skip_first_for_error
= false;
9670 if (IDENTIFIER_CDTOR_P (name
))
9672 /* Callers should explicitly indicate whether they want to ctor
9673 the complete object or just the part without virtual bases. */
9674 gcc_assert (name
!= ctor_identifier
);
9676 /* Remove the VTT pointer, if present. */
9677 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9678 && CLASSTYPE_VBASECLASSES (basetype
))
9679 skip_first_for_error
= true;
9681 /* It's OK to call destructors and constructors on cv-qualified
9682 objects. Therefore, convert the INSTANCE to the unqualified
9683 type, if necessary. */
9684 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9686 instance
= build_this (instance
);
9687 instance
= build_nop (build_pointer_type (basetype
), instance
);
9688 instance
= build_fold_indirect_ref (instance
);
9692 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9694 /* For the overload resolution we need to find the actual `this`
9695 that would be captured if the call turns out to be to a
9696 non-static member function. Do not actually capture it at this
9698 if (DECL_CONSTRUCTOR_P (fn
))
9699 /* Constructors don't use the enclosing 'this'. */
9700 first_mem_arg
= instance
;
9702 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9704 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9705 p
= conversion_obstack_alloc (0);
9707 /* The number of arguments artificial parms in ARGS; we subtract one because
9708 there's no 'this' in ARGS. */
9709 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9711 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9712 initializer, not T({ }). */
9713 if (DECL_CONSTRUCTOR_P (fn
)
9714 && vec_safe_length (user_args
) > skip
9715 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9717 tree init_list
= (*user_args
)[skip
];
9718 tree init
= NULL_TREE
;
9720 gcc_assert (user_args
->length () == skip
+ 1
9721 && !(flags
& LOOKUP_ONLYCONVERTING
));
9723 /* If the initializer list has no elements and T is a class type with
9724 a default constructor, the object is value-initialized. Handle
9725 this here so we don't need to handle it wherever we use
9726 build_special_member_call. */
9727 if (CONSTRUCTOR_NELTS (init_list
) == 0
9728 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9729 /* For a user-provided default constructor, use the normal
9730 mechanisms so that protected access works. */
9731 && type_has_non_user_provided_default_constructor (basetype
)
9732 && !processing_template_decl
)
9733 init
= build_value_init (basetype
, complain
);
9735 /* If BASETYPE is an aggregate, we need to do aggregate
9737 else if (CP_AGGREGATE_TYPE_P (basetype
))
9739 init
= reshape_init (basetype
, init_list
, complain
);
9740 init
= digest_init (basetype
, init
, complain
);
9745 if (is_dummy_object (instance
))
9746 return get_target_expr_sfinae (init
, complain
);
9747 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9748 TREE_SIDE_EFFECTS (init
) = true;
9752 /* Otherwise go ahead with overload resolution. */
9753 add_list_candidates (fns
, first_mem_arg
, user_args
,
9754 basetype
, explicit_targs
, template_only
,
9755 conversion_path
, access_binfo
, flags
,
9756 &candidates
, complain
);
9759 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9760 explicit_targs
, template_only
, conversion_path
,
9761 access_binfo
, flags
, &candidates
, complain
);
9763 any_viable_p
= false;
9764 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9768 if (complain
& tf_error
)
9769 complain_about_no_candidates_for_method_call (instance
, candidates
,
9770 explicit_targs
, basetype
,
9772 skip_first_for_error
,
9774 call
= error_mark_node
;
9778 cand
= tourney (candidates
, complain
);
9785 if (complain
& tf_error
)
9787 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9788 arglist
= build_tree_list_vec (user_args
);
9789 if (skip_first_for_error
)
9790 arglist
= TREE_CHAIN (arglist
);
9791 auto_diagnostic_group d
;
9792 if (!any_strictly_viable (candidates
))
9793 error ("no matching function for call to %<%s(%A)%>",
9794 pretty_name
, arglist
);
9796 error ("call of overloaded %<%s(%A)%> is ambiguous",
9797 pretty_name
, arglist
);
9798 print_z_candidates (location_of (name
), candidates
);
9802 call
= error_mark_node
;
9809 if (!(flags
& LOOKUP_NONVIRTUAL
)
9810 && DECL_PURE_VIRTUAL_P (fn
)
9811 && instance
== current_class_ref
9812 && (complain
& tf_warning
))
9814 /* This is not an error, it is runtime undefined
9816 if (!current_function_decl
)
9817 warning (0, "pure virtual %q#D called from "
9818 "non-static data member initializer", fn
);
9819 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9820 || DECL_DESTRUCTOR_P (current_function_decl
))
9821 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9822 ? G_("pure virtual %q#D called from constructor")
9823 : G_("pure virtual %q#D called from destructor")),
9827 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9828 && !DECL_CONSTRUCTOR_P (fn
)
9829 && is_dummy_object (instance
))
9831 instance
= maybe_resolve_dummy (instance
, true);
9832 if (instance
== error_mark_node
)
9833 call
= error_mark_node
;
9834 else if (!is_dummy_object (instance
))
9836 /* We captured 'this' in the current lambda now that
9837 we know we really need it. */
9838 cand
->first_arg
= instance
;
9840 else if (any_dependent_bases_p ())
9841 /* We can't tell until instantiation time whether we can use
9842 *this as the implicit object argument. */;
9845 if (complain
& tf_error
)
9846 error ("cannot call member function %qD without object",
9848 call
= error_mark_node
;
9852 if (call
!= error_mark_node
)
9854 /* Optimize away vtable lookup if we know that this
9855 function can't be overridden. We need to check if
9856 the context and the type where we found fn are the same,
9857 actually FN might be defined in a different class
9858 type because of a using-declaration. In this case, we
9859 do not want to perform a non-virtual call. */
9860 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9861 && same_type_ignoring_top_level_qualifiers_p
9862 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9863 && resolves_to_fixed_type_p (instance
, 0))
9864 flags
|= LOOKUP_NONVIRTUAL
;
9866 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9867 /* Now we know what function is being called. */
9870 /* Build the actual CALL_EXPR. */
9871 call
= build_over_call (cand
, flags
, complain
);
9872 /* In an expression of the form `a->f()' where `f' turns
9873 out to be a static member function, `a' is
9874 none-the-less evaluated. */
9875 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9876 && !is_dummy_object (instance
)
9877 && TREE_SIDE_EFFECTS (instance
))
9879 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9882 if (TREE_THIS_VOLATILE (a
))
9884 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9886 else if (call
!= error_mark_node
9887 && DECL_DESTRUCTOR_P (cand
->fn
)
9888 && !VOID_TYPE_P (TREE_TYPE (call
)))
9889 /* An explicit call of the form "x->~X()" has type
9890 "void". However, on platforms where destructors
9891 return "this" (i.e., those where
9892 targetm.cxx.cdtor_returns_this is true), such calls
9893 will appear to have a return value of pointer type
9894 to the low-level call machinery. We do not want to
9895 change the low-level machinery, since we want to be
9896 able to optimize "delete f()" on such platforms as
9897 "operator delete(~X(f()))" (rather than generating
9898 "t = f(), ~X(t), operator delete (t)"). */
9899 call
= build_nop (void_type_node
, call
);
9904 if (processing_template_decl
&& call
!= error_mark_node
)
9906 bool cast_to_void
= false;
9908 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9909 call
= TREE_OPERAND (call
, 1);
9910 else if (TREE_CODE (call
) == NOP_EXPR
)
9912 cast_to_void
= true;
9913 call
= TREE_OPERAND (call
, 0);
9915 if (INDIRECT_REF_P (call
))
9916 call
= TREE_OPERAND (call
, 0);
9917 call
= (build_min_non_dep_call_vec
9919 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9920 orig_instance
, orig_fns
, NULL_TREE
),
9922 SET_EXPR_LOCATION (call
, input_location
);
9923 call
= convert_from_reference (call
);
9925 call
= build_nop (void_type_node
, call
);
9928 /* Free all the conversions we allocated. */
9929 obstack_free (&conversion_obstack
, p
);
9931 if (orig_args
!= NULL
)
9932 release_tree_vector (orig_args
);
9937 /* Wrapper for above. */
9940 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9941 tree conversion_path
, int flags
,
9942 tree
*fn_p
, tsubst_flags_t complain
)
9945 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9946 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9948 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9952 /* Returns true iff standard conversion sequence ICS1 is a proper
9953 subsequence of ICS2. */
9956 is_subseq (conversion
*ics1
, conversion
*ics2
)
9958 /* We can assume that a conversion of the same code
9959 between the same types indicates a subsequence since we only get
9960 here if the types we are converting from are the same. */
9962 while (ics1
->kind
== ck_rvalue
9963 || ics1
->kind
== ck_lvalue
)
9964 ics1
= next_conversion (ics1
);
9968 while (ics2
->kind
== ck_rvalue
9969 || ics2
->kind
== ck_lvalue
)
9970 ics2
= next_conversion (ics2
);
9972 if (ics2
->kind
== ck_user
9973 || ics2
->kind
== ck_ambig
9974 || ics2
->kind
== ck_aggr
9975 || ics2
->kind
== ck_list
9976 || ics2
->kind
== ck_identity
)
9977 /* At this point, ICS1 cannot be a proper subsequence of
9978 ICS2. We can get a USER_CONV when we are comparing the
9979 second standard conversion sequence of two user conversion
9983 ics2
= next_conversion (ics2
);
9985 while (ics2
->kind
== ck_rvalue
9986 || ics2
->kind
== ck_lvalue
)
9987 ics2
= next_conversion (ics2
);
9989 if (ics2
->kind
== ics1
->kind
9990 && same_type_p (ics2
->type
, ics1
->type
)
9991 && (ics1
->kind
== ck_identity
9992 || same_type_p (next_conversion (ics2
)->type
,
9993 next_conversion (ics1
)->type
)))
9998 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9999 be any _TYPE nodes. */
10002 is_properly_derived_from (tree derived
, tree base
)
10004 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
10007 /* We only allow proper derivation here. The DERIVED_FROM_P macro
10008 considers every class derived from itself. */
10009 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
10010 && DERIVED_FROM_P (base
, derived
));
10013 /* We build the ICS for an implicit object parameter as a pointer
10014 conversion sequence. However, such a sequence should be compared
10015 as if it were a reference conversion sequence. If ICS is the
10016 implicit conversion sequence for an implicit object parameter,
10017 modify it accordingly. */
10020 maybe_handle_implicit_object (conversion
**ics
)
10022 if ((*ics
)->this_p
)
10024 /* [over.match.funcs]
10026 For non-static member functions, the type of the
10027 implicit object parameter is "reference to cv X"
10028 where X is the class of which the function is a
10029 member and cv is the cv-qualification on the member
10030 function declaration. */
10031 conversion
*t
= *ics
;
10032 tree reference_type
;
10034 /* The `this' parameter is a pointer to a class type. Make the
10035 implicit conversion talk about a reference to that same class
10037 reference_type
= TREE_TYPE (t
->type
);
10038 reference_type
= build_reference_type (reference_type
);
10040 if (t
->kind
== ck_qual
)
10041 t
= next_conversion (t
);
10042 if (t
->kind
== ck_ptr
)
10043 t
= next_conversion (t
);
10044 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
10045 t
= direct_reference_binding (reference_type
, t
);
10047 t
->rvaluedness_matches_p
= 0;
10052 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
10053 and return the initial reference binding conversion. Otherwise,
10054 leave *ICS unchanged and return NULL. */
10056 static conversion
*
10057 maybe_handle_ref_bind (conversion
**ics
)
10059 if ((*ics
)->kind
== ck_ref_bind
)
10061 conversion
*old_ics
= *ics
;
10062 *ics
= next_conversion (old_ics
);
10063 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
10070 /* Compare two implicit conversion sequences according to the rules set out in
10071 [over.ics.rank]. Return values:
10073 1: ics1 is better than ics2
10074 -1: ics2 is better than ics1
10075 0: ics1 and ics2 are indistinguishable */
10078 compare_ics (conversion
*ics1
, conversion
*ics2
)
10084 tree deref_from_type1
= NULL_TREE
;
10085 tree deref_from_type2
= NULL_TREE
;
10086 tree deref_to_type1
= NULL_TREE
;
10087 tree deref_to_type2
= NULL_TREE
;
10088 conversion_rank rank1
, rank2
;
10090 /* REF_BINDING is nonzero if the result of the conversion sequence
10091 is a reference type. In that case REF_CONV is the reference
10092 binding conversion. */
10093 conversion
*ref_conv1
;
10094 conversion
*ref_conv2
;
10096 /* Compare badness before stripping the reference conversion. */
10097 if (ics1
->bad_p
> ics2
->bad_p
)
10099 else if (ics1
->bad_p
< ics2
->bad_p
)
10102 /* Handle implicit object parameters. */
10103 maybe_handle_implicit_object (&ics1
);
10104 maybe_handle_implicit_object (&ics2
);
10106 /* Handle reference parameters. */
10107 ref_conv1
= maybe_handle_ref_bind (&ics1
);
10108 ref_conv2
= maybe_handle_ref_bind (&ics2
);
10110 /* List-initialization sequence L1 is a better conversion sequence than
10111 list-initialization sequence L2 if L1 converts to
10112 std::initializer_list<X> for some X and L2 does not. */
10113 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
10115 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
10120 When comparing the basic forms of implicit conversion sequences (as
10121 defined in _over.best.ics_)
10123 --a standard conversion sequence (_over.ics.scs_) is a better
10124 conversion sequence than a user-defined conversion sequence
10125 or an ellipsis conversion sequence, and
10127 --a user-defined conversion sequence (_over.ics.user_) is a
10128 better conversion sequence than an ellipsis conversion sequence
10129 (_over.ics.ellipsis_). */
10130 /* Use BAD_CONVERSION_RANK because we already checked for a badness
10131 mismatch. If both ICS are bad, we try to make a decision based on
10132 what would have happened if they'd been good. This is not an
10133 extension, we'll still give an error when we build up the call; this
10134 just helps us give a more helpful error message. */
10135 rank1
= BAD_CONVERSION_RANK (ics1
);
10136 rank2
= BAD_CONVERSION_RANK (ics2
);
10140 else if (rank1
< rank2
)
10143 if (ics1
->ellipsis_p
)
10144 /* Both conversions are ellipsis conversions. */
10147 /* User-defined conversion sequence U1 is a better conversion sequence
10148 than another user-defined conversion sequence U2 if they contain the
10149 same user-defined conversion operator or constructor and if the sec-
10150 ond standard conversion sequence of U1 is better than the second
10151 standard conversion sequence of U2. */
10153 /* Handle list-conversion with the same code even though it isn't always
10154 ranked as a user-defined conversion and it doesn't have a second
10155 standard conversion sequence; it will still have the desired effect.
10156 Specifically, we need to do the reference binding comparison at the
10157 end of this function. */
10159 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
10160 || ics1
->kind
== ck_aggr
|| ics2
->kind
== ck_aggr
)
10165 for (t1
= ics1
; t1
&& t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
10166 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
10167 || t1
->kind
== ck_list
)
10169 for (t2
= ics2
; t2
&& t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
10170 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
10171 || t2
->kind
== ck_list
)
10174 if (!t1
|| !t2
|| t1
->kind
!= t2
->kind
)
10176 else if (t1
->kind
== ck_user
)
10178 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10179 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10185 /* For ambiguous or aggregate conversions, use the target type as
10186 a proxy for the conversion function. */
10187 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10191 /* We can just fall through here, after setting up
10192 FROM_TYPE1 and FROM_TYPE2. */
10193 from_type1
= t1
->type
;
10194 from_type2
= t2
->type
;
10201 /* We're dealing with two standard conversion sequences.
10205 Standard conversion sequence S1 is a better conversion
10206 sequence than standard conversion sequence S2 if
10208 --S1 is a proper subsequence of S2 (comparing the conversion
10209 sequences in the canonical form defined by _over.ics.scs_,
10210 excluding any Lvalue Transformation; the identity
10211 conversion sequence is considered to be a subsequence of
10212 any non-identity conversion sequence */
10215 while (t1
->kind
!= ck_identity
)
10216 t1
= next_conversion (t1
);
10217 from_type1
= t1
->type
;
10220 while (t2
->kind
!= ck_identity
)
10221 t2
= next_conversion (t2
);
10222 from_type2
= t2
->type
;
10225 /* One sequence can only be a subsequence of the other if they start with
10226 the same type. They can start with different types when comparing the
10227 second standard conversion sequence in two user-defined conversion
10229 if (same_type_p (from_type1
, from_type2
))
10231 if (is_subseq (ics1
, ics2
))
10233 if (is_subseq (ics2
, ics1
))
10241 --the rank of S1 is better than the rank of S2 (by the rules
10244 Standard conversion sequences are ordered by their ranks: an Exact
10245 Match is a better conversion than a Promotion, which is a better
10246 conversion than a Conversion.
10248 Two conversion sequences with the same rank are indistinguishable
10249 unless one of the following rules applies:
10251 --A conversion that does not a convert a pointer, pointer to member,
10252 or std::nullptr_t to bool is better than one that does.
10254 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10255 so that we do not have to check it explicitly. */
10256 if (ics1
->rank
< ics2
->rank
)
10258 else if (ics2
->rank
< ics1
->rank
)
10261 to_type1
= ics1
->type
;
10262 to_type2
= ics2
->type
;
10264 /* A conversion from scalar arithmetic type to complex is worse than a
10265 conversion between scalar arithmetic types. */
10266 if (same_type_p (from_type1
, from_type2
)
10267 && ARITHMETIC_TYPE_P (from_type1
)
10268 && ARITHMETIC_TYPE_P (to_type1
)
10269 && ARITHMETIC_TYPE_P (to_type2
)
10270 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10271 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10273 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10279 if (TYPE_PTR_P (from_type1
)
10280 && TYPE_PTR_P (from_type2
)
10281 && TYPE_PTR_P (to_type1
)
10282 && TYPE_PTR_P (to_type2
))
10284 deref_from_type1
= TREE_TYPE (from_type1
);
10285 deref_from_type2
= TREE_TYPE (from_type2
);
10286 deref_to_type1
= TREE_TYPE (to_type1
);
10287 deref_to_type2
= TREE_TYPE (to_type2
);
10289 /* The rules for pointers to members A::* are just like the rules
10290 for pointers A*, except opposite: if B is derived from A then
10291 A::* converts to B::*, not vice versa. For that reason, we
10292 switch the from_ and to_ variables here. */
10293 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10294 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10295 || (TYPE_PTRMEMFUNC_P (from_type1
)
10296 && TYPE_PTRMEMFUNC_P (from_type2
)
10297 && TYPE_PTRMEMFUNC_P (to_type1
)
10298 && TYPE_PTRMEMFUNC_P (to_type2
)))
10300 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10301 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10302 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10303 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10306 if (deref_from_type1
!= NULL_TREE
10307 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10308 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10310 /* This was one of the pointer or pointer-like conversions.
10314 --If class B is derived directly or indirectly from class A,
10315 conversion of B* to A* is better than conversion of B* to
10316 void*, and conversion of A* to void* is better than
10317 conversion of B* to void*. */
10318 if (VOID_TYPE_P (deref_to_type1
)
10319 && VOID_TYPE_P (deref_to_type2
))
10321 if (is_properly_derived_from (deref_from_type1
,
10324 else if (is_properly_derived_from (deref_from_type2
,
10328 else if (VOID_TYPE_P (deref_to_type1
)
10329 || VOID_TYPE_P (deref_to_type2
))
10331 if (same_type_p (deref_from_type1
, deref_from_type2
))
10333 if (VOID_TYPE_P (deref_to_type2
))
10335 if (is_properly_derived_from (deref_from_type1
,
10339 /* We know that DEREF_TO_TYPE1 is `void' here. */
10340 else if (is_properly_derived_from (deref_from_type1
,
10345 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10346 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10350 --If class B is derived directly or indirectly from class A
10351 and class C is derived directly or indirectly from B,
10353 --conversion of C* to B* is better than conversion of C* to
10356 --conversion of B* to A* is better than conversion of C* to
10358 if (same_type_p (deref_from_type1
, deref_from_type2
))
10360 if (is_properly_derived_from (deref_to_type1
,
10363 else if (is_properly_derived_from (deref_to_type2
,
10367 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10369 if (is_properly_derived_from (deref_from_type2
,
10372 else if (is_properly_derived_from (deref_from_type1
,
10378 else if (CLASS_TYPE_P (non_reference (from_type1
))
10379 && same_type_p (from_type1
, from_type2
))
10381 tree from
= non_reference (from_type1
);
10385 --binding of an expression of type C to a reference of type
10386 B& is better than binding an expression of type C to a
10387 reference of type A&
10389 --conversion of C to B is better than conversion of C to A, */
10390 if (is_properly_derived_from (from
, to_type1
)
10391 && is_properly_derived_from (from
, to_type2
))
10393 if (is_properly_derived_from (to_type1
, to_type2
))
10395 else if (is_properly_derived_from (to_type2
, to_type1
))
10399 else if (CLASS_TYPE_P (non_reference (to_type1
))
10400 && same_type_p (to_type1
, to_type2
))
10402 tree to
= non_reference (to_type1
);
10406 --binding of an expression of type B to a reference of type
10407 A& is better than binding an expression of type C to a
10408 reference of type A&,
10410 --conversion of B to A is better than conversion of C to A */
10411 if (is_properly_derived_from (from_type1
, to
)
10412 && is_properly_derived_from (from_type2
, to
))
10414 if (is_properly_derived_from (from_type2
, from_type1
))
10416 else if (is_properly_derived_from (from_type1
, from_type2
))
10423 --S1 and S2 differ only in their qualification conversion and yield
10424 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10425 qualification signature of type T1 is a proper subset of the cv-
10426 qualification signature of type T2 */
10427 if (ics1
->kind
== ck_qual
10428 && ics2
->kind
== ck_qual
10429 && same_type_p (from_type1
, from_type2
))
10431 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10438 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10439 to an implicit object parameter of a non-static member function
10440 declared without a ref-qualifier, and either S1 binds an lvalue
10441 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10442 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10443 draft standard, 13.3.3.2)
10445 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10446 types to which the references refer are the same type except for
10447 top-level cv-qualifiers, and the type to which the reference
10448 initialized by S2 refers is more cv-qualified than the type to
10449 which the reference initialized by S1 refers.
10451 DR 1328 [over.match.best]: the context is an initialization by
10452 conversion function for direct reference binding (13.3.1.6) of a
10453 reference to function type, the return type of F1 is the same kind of
10454 reference (i.e. lvalue or rvalue) as the reference being initialized,
10455 and the return type of F2 is not. */
10457 if (ref_conv1
&& ref_conv2
)
10459 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10460 && (ref_conv1
->rvaluedness_matches_p
10461 != ref_conv2
->rvaluedness_matches_p
)
10462 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10463 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10464 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10466 if (ref_conv1
->bad_p
10467 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10468 TREE_TYPE (ref_conv2
->type
)))
10469 /* Don't prefer a bad conversion that drops cv-quals to a bad
10470 conversion with the wrong rvalueness. */
10472 return (ref_conv1
->rvaluedness_matches_p
10473 - ref_conv2
->rvaluedness_matches_p
);
10476 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10478 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10479 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10480 if (ref_conv1
->bad_p
)
10482 /* Prefer the one that drops fewer cv-quals. */
10483 tree ftype
= next_conversion (ref_conv1
)->type
;
10484 int fquals
= cp_type_quals (ftype
);
10488 return comp_cv_qualification (q2
, q1
);
10492 /* Neither conversion sequence is better than the other. */
10496 /* The source type for this standard conversion sequence. */
10499 source_type (conversion
*t
)
10501 for (;; t
= next_conversion (t
))
10503 if (t
->kind
== ck_user
10504 || t
->kind
== ck_ambig
10505 || t
->kind
== ck_identity
)
10508 gcc_unreachable ();
10511 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10512 a pointer to LOSER and re-running joust to produce the warning if WINNER
10513 is actually used. */
10516 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10518 candidate_warning
*cw
= (candidate_warning
*)
10519 conversion_obstack_alloc (sizeof (candidate_warning
));
10521 cw
->next
= winner
->warnings
;
10522 winner
->warnings
= cw
;
10525 /* CAND is a constructor candidate in joust in C++17 and up. If it copies a
10526 prvalue returned from a conversion function, replace CAND with the candidate
10527 for the conversion and return true. Otherwise, return false. */
10530 joust_maybe_elide_copy (z_candidate
*&cand
)
10532 tree fn
= cand
->fn
;
10533 if (!DECL_COPY_CONSTRUCTOR_P (fn
) && !DECL_MOVE_CONSTRUCTOR_P (fn
))
10535 conversion
*conv
= cand
->convs
[0];
10536 gcc_checking_assert (conv
->kind
== ck_ref_bind
);
10537 conv
= next_conversion (conv
);
10538 if (conv
->kind
== ck_user
&& !TYPE_REF_P (conv
->type
))
10540 gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p
10541 (conv
->type
, DECL_CONTEXT (fn
)));
10542 z_candidate
*uc
= conv
->cand
;
10543 if (DECL_CONV_FN_P (uc
->fn
))
10552 /* Compare two candidates for overloading as described in
10553 [over.match.best]. Return values:
10555 1: cand1 is better than cand2
10556 -1: cand2 is better than cand1
10557 0: cand1 and cand2 are indistinguishable */
10560 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10561 tsubst_flags_t complain
)
10564 int off1
= 0, off2
= 0;
10568 /* Candidates that involve bad conversions are always worse than those
10570 if (cand1
->viable
> cand2
->viable
)
10572 if (cand1
->viable
< cand2
->viable
)
10575 /* If we have two pseudo-candidates for conversions to the same type,
10576 or two candidates for the same function, arbitrarily pick one. */
10577 if (cand1
->fn
== cand2
->fn
10578 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10581 /* Prefer a non-deleted function over an implicitly deleted move
10582 constructor or assignment operator. This differs slightly from the
10583 wording for issue 1402 (which says the move op is ignored by overload
10584 resolution), but this way produces better error messages. */
10585 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10586 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10587 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10589 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10590 && move_fn_p (cand1
->fn
))
10592 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10593 && move_fn_p (cand2
->fn
))
10597 /* a viable function F1
10598 is defined to be a better function than another viable function F2 if
10599 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10600 ICSi(F2), and then */
10602 /* for some argument j, ICSj(F1) is a better conversion sequence than
10605 /* For comparing static and non-static member functions, we ignore
10606 the implicit object parameter of the non-static function. The
10607 standard says to pretend that the static function has an object
10608 parm, but that won't work with operator overloading. */
10609 len
= cand1
->num_convs
;
10610 if (len
!= cand2
->num_convs
)
10612 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10613 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10615 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10616 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10617 /* We're comparing a near-match list constructor and a near-match
10618 non-list constructor. Just treat them as unordered. */
10621 gcc_assert (static_1
!= static_2
);
10632 /* Handle C++17 copy elision in [over.match.ctor] (direct-init) context. The
10633 standard currently says that only constructors are candidates, but if one
10634 copies a prvalue returned by a conversion function we want to treat the
10635 conversion as the candidate instead.
10637 Clang does something similar, as discussed at
10638 http://lists.isocpp.org/core/2017/10/3166.php
10639 http://lists.isocpp.org/core/2019/03/5721.php */
10640 int elided_tiebreaker
= 0;
10641 if (len
== 1 && cxx_dialect
>= cxx17
10642 && DECL_P (cand1
->fn
)
10643 && DECL_COMPLETE_CONSTRUCTOR_P (cand1
->fn
)
10644 && !(cand1
->flags
& LOOKUP_ONLYCONVERTING
))
10646 bool elided1
= joust_maybe_elide_copy (cand1
);
10647 bool elided2
= joust_maybe_elide_copy (cand2
);
10648 /* As a tiebreaker below we will prefer a constructor to a conversion
10649 operator exposed this way. */
10650 elided_tiebreaker
= elided2
- elided1
;
10653 for (i
= 0; i
< len
; ++i
)
10655 conversion
*t1
= cand1
->convs
[i
+ off1
];
10656 conversion
*t2
= cand2
->convs
[i
+ off2
];
10657 int comp
= compare_ics (t1
, t2
);
10661 if ((complain
& tf_warning
)
10663 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10664 == cr_std
+ cr_promotion
)
10665 && t1
->kind
== ck_std
10666 && t2
->kind
== ck_std
10667 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10668 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10669 && (TYPE_PRECISION (t1
->type
)
10670 == TYPE_PRECISION (t2
->type
))
10671 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10672 || (TREE_CODE (next_conversion (t1
)->type
)
10673 == ENUMERAL_TYPE
)))
10675 tree type
= next_conversion (t1
)->type
;
10677 struct z_candidate
*w
, *l
;
10679 type1
= t1
->type
, type2
= t2
->type
,
10680 w
= cand1
, l
= cand2
;
10682 type1
= t2
->type
, type2
= t1
->type
,
10683 w
= cand2
, l
= cand1
;
10687 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10688 type
, type1
, type2
);
10689 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10692 add_warning (w
, l
);
10695 if (winner
&& comp
!= winner
)
10704 /* warn about confusing overload resolution for user-defined conversions,
10705 either between a constructor and a conversion op, or between two
10707 if ((complain
& tf_warning
)
10708 && winner
&& warn_conversion
&& cand1
->second_conv
10709 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10710 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10712 struct z_candidate
*w
, *l
;
10713 bool give_warning
= false;
10716 w
= cand1
, l
= cand2
;
10718 w
= cand2
, l
= cand1
;
10720 /* We don't want to complain about `X::operator T1 ()'
10721 beating `X::operator T2 () const', when T2 is a no less
10722 cv-qualified version of T1. */
10723 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10724 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10726 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10727 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10729 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10734 if (!comp_ptr_ttypes (t
, f
))
10735 give_warning
= true;
10738 give_warning
= true;
10744 tree source
= source_type (w
->convs
[0]);
10745 if (INDIRECT_TYPE_P (source
))
10746 source
= TREE_TYPE (source
);
10747 auto_diagnostic_group d
;
10748 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10749 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10750 source
, w
->second_conv
->type
))
10752 inform (input_location
, " because conversion sequence for the argument is better");
10756 add_warning (w
, l
);
10762 /* Put this tiebreaker first, so that we don't try to look at second_conv of
10763 a constructor candidate that doesn't have one. */
10764 if (elided_tiebreaker
)
10765 return elided_tiebreaker
;
10767 /* DR 495 moved this tiebreaker above the template ones. */
10768 /* or, if not that,
10769 the context is an initialization by user-defined conversion (see
10770 _dcl.init_ and _over.match.user_) and the standard conversion
10771 sequence from the return type of F1 to the destination type (i.e.,
10772 the type of the entity being initialized) is a better conversion
10773 sequence than the standard conversion sequence from the return type
10774 of F2 to the destination type. */
10776 if (cand1
->second_conv
)
10778 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10783 /* or, if not that,
10784 F1 is a non-template function and F2 is a template function
10787 if (!cand1
->template_decl
&& cand2
->template_decl
)
10789 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10792 /* or, if not that,
10793 F1 and F2 are template functions and the function template for F1 is
10794 more specialized than the template for F2 according to the partial
10797 if (cand1
->template_decl
&& cand2
->template_decl
)
10799 winner
= more_specialized_fn
10800 (TI_TEMPLATE (cand1
->template_decl
),
10801 TI_TEMPLATE (cand2
->template_decl
),
10802 /* [temp.func.order]: The presence of unused ellipsis and default
10803 arguments has no effect on the partial ordering of function
10804 templates. add_function_candidate() will not have
10805 counted the "this" argument for constructors. */
10806 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10812 // or, if not that, F1 is more constrained than F2.
10813 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10815 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10820 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10821 if (deduction_guide_p (cand1
->fn
))
10823 gcc_assert (deduction_guide_p (cand2
->fn
));
10824 /* We distinguish between candidates from an explicit deduction guide and
10825 candidates built from a constructor based on DECL_ARTIFICIAL. */
10826 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10827 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10829 return art2
- art1
;
10833 /* Prefer the special copy guide over a declared copy/move
10835 if (copy_guide_p (cand1
->fn
))
10837 if (copy_guide_p (cand2
->fn
))
10840 /* Prefer a candidate generated from a non-template constructor. */
10841 int tg1
= template_guide_p (cand1
->fn
);
10842 int tg2
= template_guide_p (cand2
->fn
);
10848 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10849 for all arguments the corresponding parameters of F1 and F2 have the same
10850 type (CWG 2273/2277). */
10851 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10852 && !DECL_CONV_FN_P (cand1
->fn
)
10853 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10854 && !DECL_CONV_FN_P (cand2
->fn
))
10856 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10857 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10859 bool used1
= false;
10860 bool used2
= false;
10861 if (base1
== base2
)
10862 /* No difference. */;
10863 else if (DERIVED_FROM_P (base1
, base2
))
10865 else if (DERIVED_FROM_P (base2
, base1
))
10868 if (int diff
= used2
- used1
)
10870 for (i
= 0; i
< len
; ++i
)
10872 conversion
*t1
= cand1
->convs
[i
+ off1
];
10873 conversion
*t2
= cand2
->convs
[i
+ off2
];
10874 if (!same_type_p (t1
->type
, t2
->type
))
10882 /* Check whether we can discard a builtin candidate, either because we
10883 have two identical ones or matching builtin and non-builtin candidates.
10885 (Pedantically in the latter case the builtin which matched the user
10886 function should not be added to the overload set, but we spot it here.
10889 ... the builtin candidates include ...
10890 - do not have the same parameter type list as any non-template
10891 non-member candidate. */
10893 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10895 for (i
= 0; i
< len
; ++i
)
10896 if (!same_type_p (cand1
->convs
[i
]->type
,
10897 cand2
->convs
[i
]->type
))
10899 if (i
== cand1
->num_convs
)
10901 if (cand1
->fn
== cand2
->fn
)
10902 /* Two built-in candidates; arbitrarily pick one. */
10904 else if (identifier_p (cand1
->fn
))
10905 /* cand1 is built-in; prefer cand2. */
10908 /* cand2 is built-in; prefer cand1. */
10913 /* For candidates of a multi-versioned function, make the version with
10914 the highest priority win. This version will be checked for dispatching
10915 first. If this version can be inlined into the caller, the front-end
10916 will simply make a direct call to this function. */
10918 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10919 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10920 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10921 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10923 tree f1
= TREE_TYPE (cand1
->fn
);
10924 tree f2
= TREE_TYPE (cand2
->fn
);
10925 tree p1
= TYPE_ARG_TYPES (f1
);
10926 tree p2
= TYPE_ARG_TYPES (f2
);
10928 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10929 is possible that cand1->fn and cand2->fn are function versions but of
10930 different functions. Check types to see if they are versions of the same
10932 if (compparms (p1
, p2
)
10933 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10935 /* Always make the version with the higher priority, more
10936 specialized, win. */
10937 gcc_assert (targetm
.compare_version_priority
);
10938 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10945 /* If the two function declarations represent the same function (this can
10946 happen with declarations in multiple scopes and arg-dependent lookup),
10947 arbitrarily choose one. But first make sure the default args we're
10949 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10950 && equal_functions (cand1
->fn
, cand2
->fn
))
10952 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10953 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10955 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10957 for (i
= 0; i
< len
; ++i
)
10959 /* Don't crash if the fn is variadic. */
10962 parms1
= TREE_CHAIN (parms1
);
10963 parms2
= TREE_CHAIN (parms2
);
10967 parms1
= TREE_CHAIN (parms1
);
10969 parms2
= TREE_CHAIN (parms2
);
10971 for (; parms1
; ++i
)
10973 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10974 TREE_PURPOSE (parms2
)))
10978 if (complain
& tf_error
)
10980 auto_diagnostic_group d
;
10981 if (permerror (input_location
,
10982 "default argument mismatch in "
10983 "overload resolution"))
10985 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10986 " candidate 1: %q#F", cand1
->fn
);
10987 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10988 " candidate 2: %q#F", cand2
->fn
);
10995 add_warning (cand1
, cand2
);
10998 parms1
= TREE_CHAIN (parms1
);
10999 parms2
= TREE_CHAIN (parms2
);
11007 /* Extension: If the worst conversion for one candidate is better than the
11008 worst conversion for the other, take the first. */
11009 if (!pedantic
&& (complain
& tf_warning_or_error
))
11011 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
11012 struct z_candidate
*w
= 0, *l
= 0;
11014 for (i
= 0; i
< len
; ++i
)
11016 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
11017 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
11018 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
11019 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
11022 winner
= 1, w
= cand1
, l
= cand2
;
11024 winner
= -1, w
= cand2
, l
= cand1
;
11027 /* Don't choose a deleted function over ambiguity. */
11028 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
11032 auto_diagnostic_group d
;
11033 if (pedwarn (input_location
, 0,
11034 "ISO C++ says that these are ambiguous, even "
11035 "though the worst conversion for the first is "
11036 "better than the worst conversion for the second:"))
11038 print_z_candidate (input_location
, _("candidate 1:"), w
);
11039 print_z_candidate (input_location
, _("candidate 2:"), l
);
11043 add_warning (w
, l
);
11048 gcc_assert (!winner
);
11052 /* Given a list of candidates for overloading, find the best one, if any.
11053 This algorithm has a worst case of O(2n) (winner is last), and a best
11054 case of O(n/2) (totally ambiguous); much better than a sorting
11057 static struct z_candidate
*
11058 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
11060 struct z_candidate
*champ
= candidates
, *challenger
;
11062 int champ_compared_to_predecessor
= 0;
11064 /* Walk through the list once, comparing each current champ to the next
11065 candidate, knocking out a candidate or two with each comparison. */
11067 for (challenger
= champ
->next
; challenger
; )
11069 fate
= joust (champ
, challenger
, 0, complain
);
11071 challenger
= challenger
->next
;
11076 champ
= challenger
->next
;
11079 champ_compared_to_predecessor
= 0;
11083 champ
= challenger
;
11084 champ_compared_to_predecessor
= 1;
11087 challenger
= champ
->next
;
11091 /* Make sure the champ is better than all the candidates it hasn't yet
11092 been compared to. */
11094 for (challenger
= candidates
;
11095 challenger
!= champ
11096 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
11097 challenger
= challenger
->next
)
11099 fate
= joust (champ
, challenger
, 0, complain
);
11107 /* Returns nonzero if things of type FROM can be converted to TO. */
11110 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
11112 tree arg
= NULL_TREE
;
11113 /* implicit_conversion only considers user-defined conversions
11114 if it has an expression for the call argument list. */
11115 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
11116 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
11117 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
11120 /* Returns nonzero if things of type FROM can be converted to TO with a
11121 standard conversion. */
11124 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
11126 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
11129 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
11132 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
11133 tsubst_flags_t complain
)
11139 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11140 p
= conversion_obstack_alloc (0);
11141 /* We want to discard any access checks done for this test,
11142 as we might not be in the appropriate access context and
11143 we'll do the check again when we actually perform the
11145 push_deferring_access_checks (dk_deferred
);
11147 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11149 ok_p
= (t
&& !t
->bad_p
);
11151 /* Discard the access checks now. */
11152 pop_deferring_access_checks ();
11153 /* Free all the conversions we allocated. */
11154 obstack_free (&conversion_obstack
, p
);
11159 /* Like can_convert_arg, but allows dubious conversions as well. */
11162 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
11163 tsubst_flags_t complain
)
11168 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11169 p
= conversion_obstack_alloc (0);
11170 /* Try to perform the conversion. */
11171 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11173 /* Free all the conversions we allocated. */
11174 obstack_free (&conversion_obstack
, p
);
11179 /* Convert EXPR to TYPE. Return the converted expression.
11181 Note that we allow bad conversions here because by the time we get to
11182 this point we are committed to doing the conversion. If we end up
11183 doing a bad conversion, convert_like will complain. */
11186 perform_implicit_conversion_flags (tree type
, tree expr
,
11187 tsubst_flags_t complain
, int flags
)
11191 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
11193 if (TYPE_REF_P (type
))
11194 expr
= mark_lvalue_use (expr
);
11196 expr
= mark_rvalue_use (expr
);
11198 if (error_operand_p (expr
))
11199 return error_mark_node
;
11201 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11202 p
= conversion_obstack_alloc (0);
11204 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11205 /*c_cast_p=*/false,
11210 if (complain
& tf_error
)
11212 /* If expr has unknown type, then it is an overloaded function.
11213 Call instantiate_type to get good error messages. */
11214 if (TREE_TYPE (expr
) == unknown_type_node
)
11215 instantiate_type (type
, expr
, complain
);
11216 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
11217 /* We gave an error. */;
11220 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
11221 gcc_rich_location
rich_loc (loc
, &label
);
11222 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
11223 expr
, TREE_TYPE (expr
), type
);
11226 expr
= error_mark_node
;
11228 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11230 /* In a template, we are only concerned about determining the
11231 type of non-dependent expressions, so we do not have to
11232 perform the actual conversion. But for initializers, we
11233 need to be able to perform it at instantiation
11234 (or instantiate_non_dependent_expr) time. */
11235 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11236 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11237 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11238 if (flags
& LOOKUP_NO_NARROWING
)
11239 IMPLICIT_CONV_EXPR_BRACED_INIT (expr
) = true;
11242 expr
= convert_like (conv
, expr
, complain
);
11244 /* Free all the conversions we allocated. */
11245 obstack_free (&conversion_obstack
, p
);
11251 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11253 return perform_implicit_conversion_flags (type
, expr
, complain
,
11257 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11258 permitted. If the conversion is valid, the converted expression is
11259 returned. Otherwise, NULL_TREE is returned, except in the case
11260 that TYPE is a class type; in that case, an error is issued. If
11261 C_CAST_P is true, then this direct-initialization is taking
11262 place as part of a static_cast being attempted as part of a C-style
11266 perform_direct_initialization_if_possible (tree type
,
11269 tsubst_flags_t complain
)
11274 if (type
== error_mark_node
|| error_operand_p (expr
))
11275 return error_mark_node
;
11278 If the destination type is a (possibly cv-qualified) class type:
11280 -- If the initialization is direct-initialization ...,
11281 constructors are considered. ... If no constructor applies, or
11282 the overload resolution is ambiguous, the initialization is
11284 if (CLASS_TYPE_P (type
))
11286 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
11287 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11288 &args
, type
, LOOKUP_NORMAL
, complain
);
11289 release_tree_vector (args
);
11290 return build_cplus_new (type
, expr
, complain
);
11293 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11294 p
= conversion_obstack_alloc (0);
11296 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11298 LOOKUP_NORMAL
, complain
);
11299 if (!conv
|| conv
->bad_p
)
11301 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11303 /* In a template, we are only concerned about determining the
11304 type of non-dependent expressions, so we do not have to
11305 perform the actual conversion. But for initializers, we
11306 need to be able to perform it at instantiation
11307 (or instantiate_non_dependent_expr) time. */
11308 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11309 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11312 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11313 /*issue_conversion_warnings=*/false,
11317 /* Free all the conversions we allocated. */
11318 obstack_free (&conversion_obstack
, p
);
11323 /* When initializing a reference that lasts longer than a full-expression,
11324 this special rule applies:
11328 The temporary to which the reference is bound or the temporary
11329 that is the complete object to which the reference is bound
11330 persists for the lifetime of the reference.
11332 The temporaries created during the evaluation of the expression
11333 initializing the reference, except the temporary to which the
11334 reference is bound, are destroyed at the end of the
11335 full-expression in which they are created.
11337 In that case, we store the converted expression into a new
11338 VAR_DECL in a new scope.
11340 However, we want to be careful not to create temporaries when
11341 they are not required. For example, given:
11344 struct D : public B {};
11348 there is no need to copy the return value from "f"; we can just
11349 extend its lifetime. Similarly, given:
11352 struct T { operator S(); };
11356 we can extend the lifetime of the return value of the conversion
11359 The next several functions are involved in this lifetime extension. */
11361 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11362 reference is being bound to a temporary. Create and return a new
11363 VAR_DECL with the indicated TYPE; this variable will store the value to
11364 which the reference is bound. */
11367 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11369 tree var
= create_temporary_var (type
);
11371 /* Register the variable. */
11373 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11375 /* Namespace-scope or local static; give it a mangled name. */
11377 /* If an initializer is visible to multiple translation units, those
11378 translation units must agree on the addresses of the
11379 temporaries. Therefore the temporaries must be given a consistent name
11380 and vague linkage. The mangled name of a temporary is the name of the
11381 non-temporary object in whose initializer they appear, prefixed with
11382 GR and suffixed with a sequence number mangled using the usual rules
11383 for a seq-id. Temporaries are numbered with a pre-order, depth-first,
11384 left-to-right walk of the complete initializer. */
11386 TREE_STATIC (var
) = TREE_STATIC (decl
);
11387 TREE_PUBLIC (var
) = TREE_PUBLIC (decl
);
11388 if (vague_linkage_p (decl
))
11389 comdat_linkage (var
);
11391 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11392 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11394 tree name
= mangle_ref_init_variable (decl
);
11395 DECL_NAME (var
) = name
;
11396 SET_DECL_ASSEMBLER_NAME (var
, name
);
11399 /* Create a new cleanup level if necessary. */
11400 maybe_push_cleanup_level (type
);
11402 return pushdecl (var
);
11405 /* EXPR is the initializer for a variable DECL of reference or
11406 std::initializer_list type. Create, push and return a new VAR_DECL
11407 for the initializer so that it will live as long as DECL. Any
11408 cleanup for the new variable is returned through CLEANUP, and the
11409 code to initialize the new variable is returned through INITP. */
11412 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11419 /* Create the temporary variable. */
11420 type
= TREE_TYPE (expr
);
11421 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11422 layout_decl (var
, 0);
11423 /* If the rvalue is the result of a function call it will be
11424 a TARGET_EXPR. If it is some other construct (such as a
11425 member access expression where the underlying object is
11426 itself the result of a function call), turn it into a
11427 TARGET_EXPR here. It is important that EXPR be a
11428 TARGET_EXPR below since otherwise the INIT_EXPR will
11429 attempt to make a bitwise copy of EXPR to initialize
11431 if (TREE_CODE (expr
) != TARGET_EXPR
)
11432 expr
= get_target_expr (expr
);
11434 if (TREE_CODE (decl
) == FIELD_DECL
11435 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11437 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11438 "until the constructor exits", decl
);
11439 TREE_NO_WARNING (decl
) = true;
11442 /* Recursively extend temps in this initializer. */
11443 TARGET_EXPR_INITIAL (expr
)
11444 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11446 /* Any reference temp has a non-trivial initializer. */
11447 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11449 /* If the initializer is constant, put it in DECL_INITIAL so we get
11450 static initialization and use in constant expressions. */
11451 init
= maybe_constant_init (expr
);
11452 /* As in store_init_value. */
11453 init
= cp_fully_fold (init
);
11454 if (TREE_CONSTANT (init
))
11456 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11458 /* 5.19 says that a constant expression can include an
11459 lvalue-rvalue conversion applied to "a glvalue of literal type
11460 that refers to a non-volatile temporary object initialized
11461 with a constant expression". Rather than try to communicate
11462 that this VAR_DECL is a temporary, just mark it constexpr. */
11463 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11464 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11465 TREE_CONSTANT (var
) = true;
11466 TREE_READONLY (var
) = true;
11468 DECL_INITIAL (var
) = init
;
11472 /* Create the INIT_EXPR that will initialize the temporary
11474 init
= split_nonconstant_init (var
, expr
);
11475 if (at_function_scope_p ())
11477 add_decl_expr (var
);
11479 if (TREE_STATIC (var
))
11480 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11483 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11485 vec_safe_push (*cleanups
, cleanup
);
11488 /* We must be careful to destroy the temporary only
11489 after its initialization has taken place. If the
11490 initialization throws an exception, then the
11491 destructor should not be run. We cannot simply
11492 transform INIT into something like:
11494 (INIT, ({ CLEANUP_STMT; }))
11496 because emit_local_var always treats the
11497 initializer as a full-expression. Thus, the
11498 destructor would run too early; it would run at the
11499 end of initializing the reference variable, rather
11500 than at the end of the block enclosing the
11501 reference variable.
11503 The solution is to pass back a cleanup expression
11504 which the caller is responsible for attaching to
11505 the statement tree. */
11509 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11510 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11512 if (CP_DECL_THREAD_LOCAL_P (var
))
11513 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11516 static_aggregates
= tree_cons (NULL_TREE
, var
,
11517 static_aggregates
);
11520 /* Check whether the dtor is callable. */
11521 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11523 /* Avoid -Wunused-variable warning (c++/38958). */
11524 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11526 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11532 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11533 initializing a variable of that TYPE. */
11536 initialize_reference (tree type
, tree expr
,
11537 int flags
, tsubst_flags_t complain
)
11541 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
11543 if (type
== error_mark_node
|| error_operand_p (expr
))
11544 return error_mark_node
;
11546 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11547 p
= conversion_obstack_alloc (0);
11549 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11551 if (!conv
|| conv
->bad_p
)
11553 if (complain
& tf_error
)
11556 convert_like (conv
, expr
, complain
);
11557 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11558 && !TYPE_REF_IS_RVALUE (type
)
11559 && !lvalue_p (expr
))
11560 error_at (loc
, "invalid initialization of non-const reference of "
11561 "type %qH from an rvalue of type %qI",
11562 type
, TREE_TYPE (expr
));
11564 error_at (loc
, "invalid initialization of reference of type "
11565 "%qH from expression of type %qI", type
,
11568 return error_mark_node
;
11571 if (conv
->kind
== ck_ref_bind
)
11572 /* Perform the conversion. */
11573 expr
= convert_like (conv
, expr
, complain
);
11574 else if (conv
->kind
== ck_ambig
)
11575 /* We gave an error in build_user_type_conversion_1. */
11576 expr
= error_mark_node
;
11578 gcc_unreachable ();
11580 /* Free all the conversions we allocated. */
11581 obstack_free (&conversion_obstack
, p
);
11586 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11587 which is bound either to a reference or a std::initializer_list. */
11590 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11595 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11597 TREE_OPERAND (sub
, 1)
11598 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11601 if (TREE_CODE (sub
) != ADDR_EXPR
)
11603 /* Deal with binding to a subobject. */
11604 for (p
= &TREE_OPERAND (sub
, 0);
11605 (TREE_CODE (*p
) == COMPONENT_REF
11606 || TREE_CODE (*p
) == ARRAY_REF
); )
11607 p
= &TREE_OPERAND (*p
, 0);
11608 if (TREE_CODE (*p
) == TARGET_EXPR
)
11610 tree subinit
= NULL_TREE
;
11611 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11612 recompute_tree_invariant_for_addr_expr (sub
);
11614 init
= fold_convert (TREE_TYPE (init
), sub
);
11616 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11621 /* INIT is part of the initializer for DECL. If there are any
11622 reference or initializer lists being initialized, extend their
11623 lifetime to match that of DECL. */
11626 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11628 tree type
= TREE_TYPE (init
);
11629 if (processing_template_decl
)
11631 if (TYPE_REF_P (type
))
11632 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11636 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11637 ctor
= TARGET_EXPR_INITIAL (ctor
);
11638 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11640 if (is_std_init_list (type
))
11642 /* The temporary array underlying a std::initializer_list
11643 is handled like a reference temporary. */
11644 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11645 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11646 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11651 constructor_elt
*p
;
11652 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11653 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11654 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11656 recompute_constructor_flags (ctor
);
11657 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11658 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11665 /* Returns true iff an initializer for TYPE could contain temporaries that
11666 need to be extended because they are bound to references or
11667 std::initializer_list. */
11670 type_has_extended_temps (tree type
)
11672 type
= strip_array_types (type
);
11673 if (TYPE_REF_P (type
))
11675 if (CLASS_TYPE_P (type
))
11677 if (is_std_init_list (type
))
11679 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11680 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11681 if (type_has_extended_temps (TREE_TYPE (f
)))
11687 /* Returns true iff TYPE is some variant of std::initializer_list. */
11690 is_std_init_list (tree type
)
11692 if (!TYPE_P (type
))
11694 if (cxx_dialect
== cxx98
)
11696 /* Look through typedefs. */
11697 type
= TYPE_MAIN_VARIANT (type
);
11698 return (CLASS_TYPE_P (type
)
11699 && CP_TYPE_CONTEXT (type
) == std_node
11700 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11703 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11704 will accept an argument list of a single std::initializer_list<T>. */
11707 is_list_ctor (tree decl
)
11709 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11712 if (!args
|| args
== void_list_node
)
11715 arg
= non_reference (TREE_VALUE (args
));
11716 if (!is_std_init_list (arg
))
11719 args
= TREE_CHAIN (args
);
11721 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11722 /* There are more non-defaulted parms. */
11728 #include "gt-cp-call.h"