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 && simple_empty_class_p (TREE_TYPE (arg
), arg
, INIT_EXPR
))
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
, N_("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_input_loc (expr
);
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 /* Don't copy a class in a template. */
4282 if (CLASS_TYPE_P (type
) && conv
->kind
== ck_rvalue
4283 && processing_template_decl
)
4284 conv
= next_conversion (conv
);
4286 conv
->check_narrowing
= true;
4287 conv
->check_narrowing_const_only
= true;
4288 expr
= convert_like (conv
, expr
, complain
);
4292 if (complain
& tf_error
)
4293 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4294 TREE_TYPE (expr
), type
);
4295 expr
= error_mark_node
;
4298 /* Free all the conversions we allocated. */
4299 obstack_free (&conversion_obstack
, p
);
4304 /* Subroutine of convert_nontype_argument.
4306 EXPR is an expression used in a context that requires a converted
4307 constant-expression, such as a template non-type parameter. Do any
4308 necessary conversions (that are permitted for converted
4309 constant-expressions) to convert it to the desired type.
4311 This function doesn't consider explicit conversion functions. If
4312 you mean to use "a contextually converted constant expression of type
4313 bool", use build_converted_constant_bool_expr.
4315 If conversion is successful, returns the converted expression;
4316 otherwise, returns error_mark_node. */
4319 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4321 return build_converted_constant_expr_internal (type
, expr
, LOOKUP_IMPLICIT
,
4325 /* Used to create "a contextually converted constant expression of type
4326 bool". This differs from build_converted_constant_expr in that it
4327 also considers explicit conversion functions. */
4330 build_converted_constant_bool_expr (tree expr
, tsubst_flags_t complain
)
4332 return build_converted_constant_expr_internal (boolean_type_node
, expr
,
4333 LOOKUP_NORMAL
, complain
);
4336 /* Do any initial processing on the arguments to a function call. */
4338 static vec
<tree
, va_gc
> *
4339 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4344 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4346 if (error_operand_p (arg
))
4348 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4350 if (complain
& tf_error
)
4351 error ("invalid use of void expression");
4354 else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg
), arg
, complain
))
4360 /* Perform overload resolution on FN, which is called with the ARGS.
4362 Return the candidate function selected by overload resolution, or
4363 NULL if the event that overload resolution failed. In the case
4364 that overload resolution fails, *CANDIDATES will be the set of
4365 candidates considered, and ANY_VIABLE_P will be set to true or
4366 false to indicate whether or not any of the candidates were
4369 The ARGS should already have gone through RESOLVE_ARGS before this
4370 function is called. */
4372 static struct z_candidate
*
4373 perform_overload_resolution (tree fn
,
4374 const vec
<tree
, va_gc
> *args
,
4375 struct z_candidate
**candidates
,
4376 bool *any_viable_p
, tsubst_flags_t complain
)
4378 struct z_candidate
*cand
;
4379 tree explicit_targs
;
4382 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4384 explicit_targs
= NULL_TREE
;
4388 *any_viable_p
= true;
4391 gcc_assert (OVL_P (fn
) || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4393 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4395 explicit_targs
= TREE_OPERAND (fn
, 1);
4396 fn
= TREE_OPERAND (fn
, 0);
4400 /* Add the various candidate functions. */
4401 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4402 explicit_targs
, template_only
,
4403 /*conversion_path=*/NULL_TREE
,
4404 /*access_path=*/NULL_TREE
,
4406 candidates
, complain
);
4408 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4410 cand
= tourney (*candidates
, complain
);
4414 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4418 /* Print an error message about being unable to build a call to FN with
4419 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4420 be located; CANDIDATES is a possibly empty list of such
4424 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4425 struct z_candidate
*candidates
)
4427 tree targs
= NULL_TREE
;
4428 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4430 targs
= TREE_OPERAND (fn
, 1);
4431 fn
= TREE_OPERAND (fn
, 0);
4433 tree name
= OVL_NAME (fn
);
4434 location_t loc
= location_of (name
);
4436 name
= lookup_template_function (name
, targs
);
4438 auto_diagnostic_group d
;
4439 if (!any_strictly_viable (candidates
))
4440 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4441 name
, build_tree_list_vec (args
));
4443 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4444 name
, build_tree_list_vec (args
));
4446 print_z_candidates (loc
, candidates
);
4449 /* Return an expression for a call to FN (a namespace-scope function,
4450 or a static member function) with the ARGS. This may change
4454 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4455 tsubst_flags_t complain
)
4457 struct z_candidate
*candidates
, *cand
;
4462 if (args
!= NULL
&& *args
!= NULL
)
4464 *args
= resolve_args (*args
, complain
);
4466 return error_mark_node
;
4470 tm_malloc_replacement (fn
);
4472 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4473 p
= conversion_obstack_alloc (0);
4475 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4480 if (complain
& tf_error
)
4482 // If there is a single (non-viable) function candidate,
4483 // let the error be diagnosed by cp_build_function_call_vec.
4484 if (!any_viable_p
&& candidates
&& ! candidates
->next
4485 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4486 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4488 // Otherwise, emit notes for non-viable candidates.
4489 print_error_for_call_failure (fn
, *args
, candidates
);
4491 result
= error_mark_node
;
4495 int flags
= LOOKUP_NORMAL
;
4496 /* If fn is template_id_expr, the call has explicit template arguments
4497 (e.g. func<int>(5)), communicate this info to build_over_call
4498 through flags so that later we can use it to decide whether to warn
4499 about peculiar null pointer conversion. */
4500 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4502 /* If overload resolution selects a specialization of a
4503 function concept for non-dependent template arguments,
4504 the expression is true if the constraints are satisfied
4505 and false otherwise.
4507 NOTE: This is an extension of Concepts Lite TS that
4508 allows constraints to be used in expressions. */
4509 if (flag_concepts
&& !processing_template_decl
)
4511 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4512 tree targs
= DECL_TI_ARGS (cand
->fn
);
4513 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4514 if (DECL_DECLARED_CONCEPT_P (decl
))
4515 return evaluate_function_concept (decl
, targs
);
4518 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4521 result
= build_over_call (cand
, flags
, complain
);
4524 /* Free all the conversions we allocated. */
4525 obstack_free (&conversion_obstack
, p
);
4530 /* Build a call to a global operator new. FNNAME is the name of the
4531 operator (either "operator new" or "operator new[]") and ARGS are
4532 the arguments provided. This may change ARGS. *SIZE points to the
4533 total number of bytes required by the allocation, and is updated if
4534 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4535 be used. If this function determines that no cookie should be
4536 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4537 is not NULL_TREE, it is evaluated before calculating the final
4538 array size, and if it fails, the array size is replaced with
4539 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4540 is non-NULL, it will be set, upon return, to the allocation
4544 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4545 tree
*size
, tree
*cookie_size
,
4546 tree align_arg
, tree size_check
,
4547 tree
*fn
, tsubst_flags_t complain
)
4549 tree original_size
= *size
;
4551 struct z_candidate
*candidates
;
4552 struct z_candidate
*cand
= NULL
;
4557 /* Set to (size_t)-1 if the size check fails. */
4558 if (size_check
!= NULL_TREE
)
4560 tree errval
= TYPE_MAX_VALUE (sizetype
);
4561 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4562 errval
= throw_bad_array_new_length ();
4563 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4564 original_size
, errval
);
4566 vec_safe_insert (*args
, 0, *size
);
4567 *args
= resolve_args (*args
, complain
);
4569 return error_mark_node
;
4575 If this lookup fails to find the name, or if the allocated type
4576 is not a class type, the allocation function's name is looked
4577 up in the global scope.
4579 we disregard block-scope declarations of "operator new". */
4580 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4581 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4585 vec
<tree
, va_gc
>* align_args
4586 = vec_copy_and_insert (*args
, align_arg
, 1);
4587 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4588 &any_viable_p
, tf_none
);
4591 /* If no aligned allocation function matches, try again without the
4595 /* Figure out what function is being called. */
4597 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4600 /* If no suitable function could be found, issue an error message
4604 if (complain
& tf_error
)
4605 print_error_for_call_failure (fns
, *args
, candidates
);
4606 return error_mark_node
;
4609 /* If a cookie is required, add some extra space. Whether
4610 or not a cookie is required cannot be determined until
4611 after we know which function was called. */
4614 bool use_cookie
= true;
4617 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4618 /* Skip the size_t parameter. */
4619 arg_types
= TREE_CHAIN (arg_types
);
4620 /* Check the remaining parameters (if any). */
4622 && TREE_CHAIN (arg_types
) == void_list_node
4623 && same_type_p (TREE_VALUE (arg_types
),
4626 /* If we need a cookie, adjust the number of bytes allocated. */
4629 /* Update the total size. */
4630 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4633 /* Set to (size_t)-1 if the size check fails. */
4634 gcc_assert (size_check
!= NULL_TREE
);
4635 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4636 *size
, TYPE_MAX_VALUE (sizetype
));
4638 /* Update the argument list to reflect the adjusted size. */
4639 (**args
)[0] = *size
;
4642 *cookie_size
= NULL_TREE
;
4645 /* Tell our caller which function we decided to call. */
4649 /* Build the CALL_EXPR. */
4650 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4653 /* Build a new call to operator(). This may change ARGS. */
4656 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4658 struct z_candidate
*candidates
= 0, *cand
;
4659 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4661 tree result
= NULL_TREE
;
4664 obj
= mark_lvalue_use (obj
);
4666 if (error_operand_p (obj
))
4667 return error_mark_node
;
4669 tree type
= TREE_TYPE (obj
);
4671 obj
= prep_operand (obj
);
4673 if (TYPE_PTRMEMFUNC_P (type
))
4675 if (complain
& tf_error
)
4676 /* It's no good looking for an overloaded operator() on a
4677 pointer-to-member-function. */
4678 error ("pointer-to-member function %qE cannot be called without "
4679 "an object; consider using %<.*%> or %<->*%>", obj
);
4680 return error_mark_node
;
4683 if (TYPE_BINFO (type
))
4685 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4686 if (fns
== error_mark_node
)
4687 return error_mark_node
;
4692 if (args
!= NULL
&& *args
!= NULL
)
4694 *args
= resolve_args (*args
, complain
);
4696 return error_mark_node
;
4699 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4700 p
= conversion_obstack_alloc (0);
4704 first_mem_arg
= obj
;
4706 add_candidates (BASELINK_FUNCTIONS (fns
),
4707 first_mem_arg
, *args
, NULL_TREE
,
4709 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4710 LOOKUP_NORMAL
, &candidates
, complain
);
4713 convs
= lookup_conversions (type
);
4715 for (; convs
; convs
= TREE_CHAIN (convs
))
4717 tree totype
= TREE_TYPE (convs
);
4719 if (TYPE_PTRFN_P (totype
)
4720 || TYPE_REFFN_P (totype
)
4721 || (TYPE_REF_P (totype
)
4722 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4723 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4727 if (DECL_NONCONVERTING_P (fn
))
4730 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4731 add_template_conv_candidate
4732 (&candidates
, fn
, obj
, *args
, totype
,
4733 /*access_path=*/NULL_TREE
,
4734 /*conversion_path=*/NULL_TREE
, complain
);
4736 add_conv_candidate (&candidates
, fn
, obj
,
4737 *args
, /*conversion_path=*/NULL_TREE
,
4738 /*access_path=*/NULL_TREE
, complain
);
4742 /* Be strict here because if we choose a bad conversion candidate, the
4743 errors we get won't mention the call context. */
4744 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4747 if (complain
& tf_error
)
4749 auto_diagnostic_group d
;
4750 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4751 build_tree_list_vec (*args
));
4752 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4754 result
= error_mark_node
;
4758 cand
= tourney (candidates
, complain
);
4761 if (complain
& tf_error
)
4763 auto_diagnostic_group d
;
4764 error ("call of %<(%T) (%A)%> is ambiguous",
4765 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4766 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4768 result
= error_mark_node
;
4770 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4771 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4772 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4773 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4776 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4777 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4781 gcc_checking_assert (TYPE_P (cand
->fn
));
4782 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4784 obj
= convert_from_reference (obj
);
4785 result
= cp_build_function_call_vec (obj
, args
, complain
);
4789 /* Free all the conversions we allocated. */
4790 obstack_free (&conversion_obstack
, p
);
4795 /* Wrapper for above. */
4798 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4801 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4802 ret
= build_op_call_1 (obj
, args
, complain
);
4803 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4807 /* Called by op_error to prepare format strings suitable for the error
4808 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4809 and a suffix (controlled by NTYPES). */
4812 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4816 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4817 : G_("no match for "), errmsg
, NULL
);
4820 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4821 else if (ntypes
== 2)
4822 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4824 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4830 op_error (const op_location_t
&loc
,
4831 enum tree_code code
, enum tree_code code2
,
4832 tree arg1
, tree arg2
, tree arg3
, bool match
)
4834 bool assop
= code
== MODIFY_EXPR
;
4835 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4840 if (flag_diagnostics_show_caret
)
4841 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4843 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4845 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4846 "in %<%E ? %E : %E%>"), 3, match
),
4848 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4851 case POSTINCREMENT_EXPR
:
4852 case POSTDECREMENT_EXPR
:
4853 if (flag_diagnostics_show_caret
)
4854 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4855 opname
, TREE_TYPE (arg1
));
4857 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4859 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4863 if (flag_diagnostics_show_caret
)
4864 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4865 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4867 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4869 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4874 if (flag_diagnostics_show_caret
)
4875 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4876 opname
, TREE_TYPE (arg1
));
4878 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4879 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4884 if (flag_diagnostics_show_caret
)
4886 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4888 op_error_string (G_("%<operator%s%>"), 2, match
),
4889 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4892 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4894 opname
, arg1
, opname
, arg2
,
4895 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4897 if (flag_diagnostics_show_caret
)
4898 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4899 opname
, TREE_TYPE (arg1
));
4901 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4903 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4908 /* Return the implicit conversion sequence that could be used to
4909 convert E1 to E2 in [expr.cond]. */
4912 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4914 tree t1
= non_reference (TREE_TYPE (e1
));
4915 tree t2
= non_reference (TREE_TYPE (e2
));
4921 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4922 implicitly converted (clause _conv_) to the type "lvalue reference to
4923 T2", subject to the constraint that in the conversion the
4924 reference must bind directly (_dcl.init.ref_) to an lvalue.
4926 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4927 implicitly converted to the type "rvalue reference to T2", subject to
4928 the constraint that the reference must bind directly. */
4931 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4932 conv
= implicit_conversion (rtype
,
4936 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4937 |LOOKUP_ONLYCONVERTING
,
4939 if (conv
&& !conv
->bad_p
)
4943 /* If E2 is a prvalue or if neither of the conversions above can be done
4944 and at least one of the operands has (possibly cv-qualified) class
4946 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4951 If E1 and E2 have class type, and the underlying class types are
4952 the same or one is a base class of the other: E1 can be converted
4953 to match E2 if the class of T2 is the same type as, or a base
4954 class of, the class of T1, and the cv-qualification of T2 is the
4955 same cv-qualification as, or a greater cv-qualification than, the
4956 cv-qualification of T1. If the conversion is applied, E1 is
4957 changed to an rvalue of type T2 that still refers to the original
4958 source class object (or the appropriate subobject thereof). */
4959 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4960 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4962 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4964 conv
= build_identity_conv (t1
, e1
);
4965 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4966 TYPE_MAIN_VARIANT (t2
)))
4967 conv
= build_conv (ck_base
, t2
, conv
);
4969 conv
= build_conv (ck_rvalue
, t2
, conv
);
4978 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4979 converted to the type that expression E2 would have if E2 were
4980 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4981 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4982 LOOKUP_IMPLICIT
, complain
);
4985 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4986 arguments to the conditional expression. */
4989 build_conditional_expr_1 (const op_location_t
&loc
,
4990 tree arg1
, tree arg2
, tree arg3
,
4991 tsubst_flags_t complain
)
4995 tree result
= NULL_TREE
;
4996 tree result_type
= NULL_TREE
;
4997 bool is_glvalue
= true;
4998 struct z_candidate
*candidates
= 0;
4999 struct z_candidate
*cand
;
5001 tree orig_arg2
, orig_arg3
;
5003 /* As a G++ extension, the second argument to the conditional can be
5004 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
5005 c'.) If the second operand is omitted, make sure it is
5006 calculated only once. */
5009 if (complain
& tf_error
)
5010 pedwarn (loc
, OPT_Wpedantic
,
5011 "ISO C++ forbids omitting the middle term of "
5012 "a %<?:%> expression");
5014 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
5015 warn_for_omitted_condop (loc
, arg1
);
5017 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
5018 if (lvalue_p (arg1
))
5019 arg2
= arg1
= cp_stabilize_reference (arg1
);
5021 arg2
= arg1
= cp_save_expr (arg1
);
5024 /* If something has already gone wrong, just pass that fact up the
5026 if (error_operand_p (arg1
)
5027 || error_operand_p (arg2
)
5028 || error_operand_p (arg3
))
5029 return error_mark_node
;
5034 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
5036 tree arg1_type
= TREE_TYPE (arg1
);
5038 /* If arg1 is another cond_expr choosing between -1 and 0,
5039 then we can use its comparison. It may help to avoid
5040 additional comparison, produce more accurate diagnostics
5041 and enables folding. */
5042 if (TREE_CODE (arg1
) == VEC_COND_EXPR
5043 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
5044 && integer_zerop (TREE_OPERAND (arg1
, 2)))
5045 arg1
= TREE_OPERAND (arg1
, 0);
5047 arg1
= force_rvalue (arg1
, complain
);
5048 arg2
= force_rvalue (arg2
, complain
);
5049 arg3
= force_rvalue (arg3
, complain
);
5051 /* force_rvalue can return error_mark on valid arguments. */
5052 if (error_operand_p (arg1
)
5053 || error_operand_p (arg2
)
5054 || error_operand_p (arg3
))
5055 return error_mark_node
;
5057 arg2_type
= TREE_TYPE (arg2
);
5058 arg3_type
= TREE_TYPE (arg3
);
5060 if (!VECTOR_TYPE_P (arg2_type
)
5061 && !VECTOR_TYPE_P (arg3_type
))
5063 /* Rely on the error messages of the scalar version. */
5064 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
5065 orig_arg2
, orig_arg3
, complain
);
5066 if (scal
== error_mark_node
)
5067 return error_mark_node
;
5068 tree stype
= TREE_TYPE (scal
);
5069 tree ctype
= TREE_TYPE (arg1_type
);
5070 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
5071 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
5073 if (complain
& tf_error
)
5074 error_at (loc
, "inferred scalar type %qT is not an integer or "
5075 "floating-point type of the same size as %qT", stype
,
5076 COMPARISON_CLASS_P (arg1
)
5077 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
5079 return error_mark_node
;
5082 tree vtype
= build_opaque_vector_type (stype
,
5083 TYPE_VECTOR_SUBPARTS (arg1_type
));
5084 /* We could pass complain & tf_warning to unsafe_conversion_p,
5085 but the warnings (like Wsign-conversion) have already been
5086 given by the scalar build_conditional_expr_1. We still check
5087 unsafe_conversion_p to forbid truncating long long -> float. */
5088 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
5090 if (complain
& tf_error
)
5091 error_at (loc
, "conversion of scalar %qH to vector %qI "
5092 "involves truncation", arg2_type
, vtype
);
5093 return error_mark_node
;
5095 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
5097 if (complain
& tf_error
)
5098 error_at (loc
, "conversion of scalar %qH to vector %qI "
5099 "involves truncation", arg3_type
, vtype
);
5100 return error_mark_node
;
5103 arg2
= cp_convert (stype
, arg2
, complain
);
5104 arg2
= save_expr (arg2
);
5105 arg2
= build_vector_from_val (vtype
, arg2
);
5107 arg3
= cp_convert (stype
, arg3
, complain
);
5108 arg3
= save_expr (arg3
);
5109 arg3
= build_vector_from_val (vtype
, arg3
);
5113 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5115 enum stv_conv convert_flag
=
5116 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5117 complain
& tf_error
);
5119 switch (convert_flag
)
5122 return error_mark_node
;
5125 arg2
= save_expr (arg2
);
5126 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5127 arg2
= build_vector_from_val (arg3_type
, arg2
);
5128 arg2_type
= TREE_TYPE (arg2
);
5133 arg3
= save_expr (arg3
);
5134 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5135 arg3
= build_vector_from_val (arg2_type
, arg3
);
5136 arg3_type
= TREE_TYPE (arg3
);
5144 if (!same_type_p (arg2_type
, arg3_type
)
5145 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5146 TYPE_VECTOR_SUBPARTS (arg2_type
))
5147 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5149 if (complain
& tf_error
)
5151 "incompatible vector types in conditional expression: "
5152 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5153 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5154 return error_mark_node
;
5157 if (!COMPARISON_CLASS_P (arg1
))
5159 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5160 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5162 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5167 The first expression is implicitly converted to bool (clause
5169 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5171 if (error_operand_p (arg1
))
5172 return error_mark_node
;
5176 If either the second or the third operand has type (possibly
5177 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5178 array-to-pointer (_conv.array_), and function-to-pointer
5179 (_conv.func_) standard conversions are performed on the second
5180 and third operands. */
5181 arg2_type
= unlowered_expr_type (arg2
);
5182 arg3_type
= unlowered_expr_type (arg3
);
5183 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5185 /* 'void' won't help in resolving an overloaded expression on the
5186 other side, so require it to resolve by itself. */
5187 if (arg2_type
== unknown_type_node
)
5189 arg2
= resolve_nondeduced_context_or_error (arg2
, complain
);
5190 arg2_type
= TREE_TYPE (arg2
);
5192 if (arg3_type
== unknown_type_node
)
5194 arg3
= resolve_nondeduced_context_or_error (arg3
, complain
);
5195 arg3_type
= TREE_TYPE (arg3
);
5200 One of the following shall hold:
5202 --The second or the third operand (but not both) is a
5203 throw-expression (_except.throw_); the result is of the type
5204 and value category of the other.
5206 --Both the second and the third operands have type void; the
5207 result is of type void and is a prvalue. */
5208 if (TREE_CODE (arg2
) == THROW_EXPR
5209 && TREE_CODE (arg3
) != THROW_EXPR
)
5211 result_type
= arg3_type
;
5212 is_glvalue
= glvalue_p (arg3
);
5214 else if (TREE_CODE (arg2
) != THROW_EXPR
5215 && TREE_CODE (arg3
) == THROW_EXPR
)
5217 result_type
= arg2_type
;
5218 is_glvalue
= glvalue_p (arg2
);
5220 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5222 result_type
= void_type_node
;
5227 if (complain
& tf_error
)
5229 if (VOID_TYPE_P (arg2_type
))
5230 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5231 "second operand to the conditional operator "
5232 "is of type %<void%>, but the third operand is "
5233 "neither a throw-expression nor of type %<void%>");
5235 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5236 "third operand to the conditional operator "
5237 "is of type %<void%>, but the second operand is "
5238 "neither a throw-expression nor of type %<void%>");
5240 return error_mark_node
;
5243 goto valid_operands
;
5247 Otherwise, if the second and third operand have different types,
5248 and either has (possibly cv-qualified) class type, or if both are
5249 glvalues of the same value category and the same type except for
5250 cv-qualification, an attempt is made to convert each of those operands
5251 to the type of the other. */
5252 else if (!same_type_p (arg2_type
, arg3_type
)
5253 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5254 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5256 && glvalue_p (arg2
) && glvalue_p (arg3
)
5257 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5261 bool converted
= false;
5263 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5264 p
= conversion_obstack_alloc (0);
5266 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5267 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5271 If both can be converted, or one can be converted but the
5272 conversion is ambiguous, the program is ill-formed. If
5273 neither can be converted, the operands are left unchanged and
5274 further checking is performed as described below. If exactly
5275 one conversion is possible, that conversion is applied to the
5276 chosen operand and the converted operand is used in place of
5277 the original operand for the remainder of this section. */
5278 if ((conv2
&& !conv2
->bad_p
5279 && conv3
&& !conv3
->bad_p
)
5280 || (conv2
&& conv2
->kind
== ck_ambig
)
5281 || (conv3
&& conv3
->kind
== ck_ambig
))
5283 if (complain
& tf_error
)
5285 error_at (loc
, "operands to %<?:%> have different types "
5287 arg2_type
, arg3_type
);
5288 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5289 inform (loc
, " and each type can be converted to the other");
5290 else if (conv2
&& conv2
->kind
== ck_ambig
)
5291 convert_like (conv2
, arg2
, complain
);
5293 convert_like (conv3
, arg3
, complain
);
5295 result
= error_mark_node
;
5297 else if (conv2
&& !conv2
->bad_p
)
5299 arg2
= convert_like (conv2
, arg2
, complain
);
5300 arg2
= convert_from_reference (arg2
);
5301 arg2_type
= TREE_TYPE (arg2
);
5302 /* Even if CONV2 is a valid conversion, the result of the
5303 conversion may be invalid. For example, if ARG3 has type
5304 "volatile X", and X does not have a copy constructor
5305 accepting a "volatile X&", then even if ARG2 can be
5306 converted to X, the conversion will fail. */
5307 if (error_operand_p (arg2
))
5308 result
= error_mark_node
;
5311 else if (conv3
&& !conv3
->bad_p
)
5313 arg3
= convert_like (conv3
, arg3
, complain
);
5314 arg3
= convert_from_reference (arg3
);
5315 arg3_type
= TREE_TYPE (arg3
);
5316 if (error_operand_p (arg3
))
5317 result
= error_mark_node
;
5321 /* Free all the conversions we allocated. */
5322 obstack_free (&conversion_obstack
, p
);
5327 /* If, after the conversion, both operands have class type,
5328 treat the cv-qualification of both operands as if it were the
5329 union of the cv-qualification of the operands.
5331 The standard is not clear about what to do in this
5332 circumstance. For example, if the first operand has type
5333 "const X" and the second operand has a user-defined
5334 conversion to "volatile X", what is the type of the second
5335 operand after this step? Making it be "const X" (matching
5336 the first operand) seems wrong, as that discards the
5337 qualification without actually performing a copy. Leaving it
5338 as "volatile X" seems wrong as that will result in the
5339 conditional expression failing altogether, even though,
5340 according to this step, the one operand could be converted to
5341 the type of the other. */
5343 && CLASS_TYPE_P (arg2_type
)
5344 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5345 arg2_type
= arg3_type
=
5346 cp_build_qualified_type (arg2_type
,
5347 cp_type_quals (arg2_type
)
5348 | cp_type_quals (arg3_type
));
5353 If the second and third operands are glvalues of the same value
5354 category and have the same type, the result is of that type and
5356 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5357 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5358 && same_type_p (arg2_type
, arg3_type
))
5360 result_type
= arg2_type
;
5361 arg2
= mark_lvalue_use (arg2
);
5362 arg3
= mark_lvalue_use (arg3
);
5363 goto valid_operands
;
5368 Otherwise, the result is an rvalue. If the second and third
5369 operand do not have the same type, and either has (possibly
5370 cv-qualified) class type, overload resolution is used to
5371 determine the conversions (if any) to be applied to the operands
5372 (_over.match.oper_, _over.built_). */
5374 if (!same_type_p (arg2_type
, arg3_type
)
5375 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5381 /* Rearrange the arguments so that add_builtin_candidate only has
5382 to know about two args. In build_builtin_candidate, the
5383 arguments are unscrambled. */
5387 add_builtin_candidates (&candidates
,
5390 ovl_op_identifier (false, COND_EXPR
),
5392 LOOKUP_NORMAL
, complain
);
5396 If the overload resolution fails, the program is
5398 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5401 if (complain
& tf_error
)
5402 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5403 arg2_type
, arg3_type
);
5404 return error_mark_node
;
5406 cand
= tourney (candidates
, complain
);
5409 if (complain
& tf_error
)
5411 auto_diagnostic_group d
;
5412 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5413 print_z_candidates (loc
, candidates
);
5415 return error_mark_node
;
5420 Otherwise, the conversions thus determined are applied, and
5421 the converted operands are used in place of the original
5422 operands for the remainder of this section. */
5423 conv
= cand
->convs
[0];
5424 arg1
= convert_like (conv
, arg1
, complain
);
5425 conv
= cand
->convs
[1];
5426 arg2
= convert_like (conv
, arg2
, complain
);
5427 arg2_type
= TREE_TYPE (arg2
);
5428 conv
= cand
->convs
[2];
5429 arg3
= convert_like (conv
, arg3
, complain
);
5430 arg3_type
= TREE_TYPE (arg3
);
5435 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5436 and function-to-pointer (_conv.func_) standard conversions are
5437 performed on the second and third operands.
5439 We need to force the lvalue-to-rvalue conversion here for class types,
5440 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5441 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5444 arg2
= force_rvalue (arg2
, complain
);
5445 if (!CLASS_TYPE_P (arg2_type
))
5446 arg2_type
= TREE_TYPE (arg2
);
5448 arg3
= force_rvalue (arg3
, complain
);
5449 if (!CLASS_TYPE_P (arg3_type
))
5450 arg3_type
= TREE_TYPE (arg3
);
5452 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5453 return error_mark_node
;
5457 After those conversions, one of the following shall hold:
5459 --The second and third operands have the same type; the result is of
5461 if (same_type_p (arg2_type
, arg3_type
))
5462 result_type
= arg2_type
;
5465 --The second and third operands have arithmetic or enumeration
5466 type; the usual arithmetic conversions are performed to bring
5467 them to a common type, and the result is of that type. */
5468 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5469 || UNSCOPED_ENUM_P (arg2_type
))
5470 && (ARITHMETIC_TYPE_P (arg3_type
)
5471 || UNSCOPED_ENUM_P (arg3_type
)))
5473 /* In this case, there is always a common type. */
5474 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5476 if (complain
& tf_warning
)
5477 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5478 "implicit conversion from %qH to %qI to "
5479 "match other result of conditional",
5482 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5483 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5485 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5486 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5487 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5488 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5489 && (DECL_CONTEXT (stripped_orig_arg2
)
5490 == DECL_CONTEXT (stripped_orig_arg3
)))
5491 /* Two enumerators from the same enumeration can have different
5492 types when the enumeration is still being defined. */;
5493 else if (complain
& tf_warning
)
5494 warning_at (loc
, OPT_Wenum_compare
, "enumerated mismatch "
5495 "in conditional expression: %qT vs %qT",
5496 arg2_type
, arg3_type
);
5498 else if (extra_warnings
5499 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5500 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5501 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5502 && !same_type_p (arg2_type
,
5503 type_promotes_to (arg3_type
)))))
5505 if (complain
& tf_warning
)
5506 warning_at (loc
, OPT_Wextra
, "enumerated and non-enumerated "
5507 "type in conditional expression");
5510 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5511 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5515 --The second and third operands have pointer type, or one has
5516 pointer type and the other is a null pointer constant; pointer
5517 conversions (_conv.ptr_) and qualification conversions
5518 (_conv.qual_) are performed to bring them to their composite
5519 pointer type (_expr.rel_). The result is of the composite
5522 --The second and third operands have pointer to member type, or
5523 one has pointer to member type and the other is a null pointer
5524 constant; pointer to member conversions (_conv.mem_) and
5525 qualification conversions (_conv.qual_) are performed to bring
5526 them to a common type, whose cv-qualification shall match the
5527 cv-qualification of either the second or the third operand.
5528 The result is of the common type. */
5529 else if ((null_ptr_cst_p (arg2
)
5530 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5531 || (null_ptr_cst_p (arg3
)
5532 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5533 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5534 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5535 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5537 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5538 arg3
, CPO_CONDITIONAL_EXPR
,
5540 if (result_type
== error_mark_node
)
5541 return error_mark_node
;
5542 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5543 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5548 if (complain
& tf_error
)
5549 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5550 arg2_type
, arg3_type
);
5551 return error_mark_node
;
5554 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5555 return error_mark_node
;
5558 if (processing_template_decl
&& is_glvalue
)
5560 /* Let lvalue_kind know this was a glvalue. */
5561 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5562 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5565 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5567 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5568 warn here, because the COND_EXPR will be turned into ARG2. */
5569 if (warn_duplicated_branches
5570 && (complain
& tf_warning
)
5571 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5572 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5573 "this condition has identical branches");
5575 /* We can't use result_type below, as fold might have returned a
5580 /* Expand both sides into the same slot, hopefully the target of
5581 the ?: expression. We used to check for TARGET_EXPRs here,
5582 but now we sometimes wrap them in NOP_EXPRs so the test would
5584 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5585 result
= get_target_expr_sfinae (result
, complain
);
5586 /* If this expression is an rvalue, but might be mistaken for an
5587 lvalue, we must add a NON_LVALUE_EXPR. */
5588 result
= rvalue (result
);
5591 result
= force_paren_expr (result
);
5596 /* Wrapper for above. */
5599 build_conditional_expr (const op_location_t
&loc
,
5600 tree arg1
, tree arg2
, tree arg3
,
5601 tsubst_flags_t complain
)
5604 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5605 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5606 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5610 /* OPERAND is an operand to an expression. Perform necessary steps
5611 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5615 prep_operand (tree operand
)
5619 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5620 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5621 /* Make sure the template type is instantiated now. */
5622 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5628 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5629 OVERLOAD) to the CANDIDATES, returning an updated list of
5630 CANDIDATES. The ARGS are the arguments provided to the call;
5631 if FIRST_ARG is non-null it is the implicit object argument,
5632 otherwise the first element of ARGS is used if needed. The
5633 EXPLICIT_TARGS are explicit template arguments provided.
5634 TEMPLATE_ONLY is true if only template functions should be
5635 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5636 add_function_candidate. */
5639 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5641 tree explicit_targs
, bool template_only
,
5642 tree conversion_path
, tree access_path
,
5644 struct z_candidate
**candidates
,
5645 tsubst_flags_t complain
)
5648 const vec
<tree
, va_gc
> *non_static_args
;
5649 bool check_list_ctor
= false;
5650 bool check_converting
= false;
5651 unification_kind_t strict
;
5656 /* Precalculate special handling of constructors and conversion ops. */
5657 tree fn
= OVL_FIRST (fns
);
5658 if (DECL_CONV_FN_P (fn
))
5660 check_list_ctor
= false;
5661 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5662 if (flags
& LOOKUP_NO_CONVERSION
)
5663 /* We're doing return_type(x). */
5664 strict
= DEDUCE_CONV
;
5666 /* We're doing x.operator return_type(). */
5667 strict
= DEDUCE_EXACT
;
5668 /* [over.match.funcs] For conversion functions, the function
5669 is considered to be a member of the class of the implicit
5670 object argument for the purpose of defining the type of
5671 the implicit object parameter. */
5672 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5676 if (DECL_CONSTRUCTOR_P (fn
))
5678 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5679 /* For list-initialization we consider explicit constructors
5680 and complain if one is chosen. */
5682 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5683 == LOOKUP_ONLYCONVERTING
);
5685 strict
= DEDUCE_CALL
;
5686 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5690 non_static_args
= args
;
5692 /* Delay creating the implicit this parameter until it is needed. */
5693 non_static_args
= NULL
;
5695 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5699 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5701 if (check_list_ctor
&& !is_list_ctor (fn
))
5704 tree fn_first_arg
= NULL_TREE
;
5705 const vec
<tree
, va_gc
> *fn_args
= args
;
5707 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5709 /* Figure out where the object arg comes from. If this
5710 function is a non-static member and we didn't get an
5711 implicit object argument, move it out of args. */
5712 if (first_arg
== NULL_TREE
)
5716 vec
<tree
, va_gc
> *tempvec
;
5717 vec_alloc (tempvec
, args
->length () - 1);
5718 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5719 tempvec
->quick_push (arg
);
5720 non_static_args
= tempvec
;
5721 first_arg
= (*args
)[0];
5724 fn_first_arg
= first_arg
;
5725 fn_args
= non_static_args
;
5728 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5729 add_template_candidate (candidates
,
5741 else if (!template_only
)
5742 add_function_candidate (candidates
,
5755 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5756 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5759 op_is_ordered (tree_code code
)
5765 return (flag_strong_eval_order
> 1 ? -1 : 0);
5769 return (flag_strong_eval_order
> 1 ? 1 : 0);
5772 // Not overloadable (yet).
5774 // Only one argument.
5781 return (flag_strong_eval_order
? 1 : 0);
5789 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5790 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5791 tsubst_flags_t complain
)
5793 struct z_candidate
*candidates
= 0, *cand
;
5794 vec
<tree
, va_gc
> *arglist
;
5796 tree result
= NULL_TREE
;
5797 bool result_valid_p
= false;
5798 enum tree_code code2
= NOP_EXPR
;
5799 enum tree_code code_orig_arg1
= ERROR_MARK
;
5800 enum tree_code code_orig_arg2
= ERROR_MARK
;
5806 if (error_operand_p (arg1
)
5807 || error_operand_p (arg2
)
5808 || error_operand_p (arg3
))
5809 return error_mark_node
;
5811 bool ismodop
= code
== MODIFY_EXPR
;
5814 code2
= TREE_CODE (arg3
);
5817 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5819 arg1
= prep_operand (arg1
);
5821 bool memonly
= false;
5826 case VEC_DELETE_EXPR
:
5828 /* Use build_op_new_call and build_op_delete_call instead. */
5832 /* Use build_op_call instead. */
5835 case TRUTH_ORIF_EXPR
:
5836 case TRUTH_ANDIF_EXPR
:
5837 case TRUTH_AND_EXPR
:
5839 /* These are saved for the sake of warn_logical_operator. */
5840 code_orig_arg1
= TREE_CODE (arg1
);
5841 code_orig_arg2
= TREE_CODE (arg2
);
5849 /* These are saved for the sake of maybe_warn_bool_compare. */
5850 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5851 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5854 /* =, ->, [], () must be non-static member functions. */
5856 if (code2
!= NOP_EXPR
)
5868 arg2
= prep_operand (arg2
);
5869 arg3
= prep_operand (arg3
);
5871 if (code
== COND_EXPR
)
5872 /* Use build_conditional_expr instead. */
5874 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5875 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5878 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5879 arg2
= integer_zero_node
;
5881 vec_alloc (arglist
, 3);
5882 arglist
->quick_push (arg1
);
5883 if (arg2
!= NULL_TREE
)
5884 arglist
->quick_push (arg2
);
5885 if (arg3
!= NULL_TREE
)
5886 arglist
->quick_push (arg3
);
5888 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5889 p
= conversion_obstack_alloc (0);
5891 /* Add namespace-scope operators to the list of functions to
5895 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5896 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5897 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5898 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5899 flags
, &candidates
, complain
);
5904 args
[2] = NULL_TREE
;
5906 /* Add class-member operators to the candidate set. */
5907 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5911 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5912 if (fns
== error_mark_node
)
5914 result
= error_mark_node
;
5915 goto user_defined_result_ready
;
5918 add_candidates (BASELINK_FUNCTIONS (fns
),
5919 NULL_TREE
, arglist
, NULL_TREE
,
5921 BASELINK_BINFO (fns
),
5922 BASELINK_ACCESS_BINFO (fns
),
5923 flags
, &candidates
, complain
);
5925 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5926 only non-member functions that have type T1 or reference to
5927 cv-qualified-opt T1 for the first argument, if the first argument
5928 has an enumeration type, or T2 or reference to cv-qualified-opt
5929 T2 for the second argument, if the second argument has an
5930 enumeration type. Filter out those that don't match. */
5931 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5933 struct z_candidate
**candp
, **next
;
5935 for (candp
= &candidates
; *candp
; candp
= next
)
5937 tree parmlist
, parmtype
;
5938 int i
, nargs
= (arg2
? 2 : 1);
5943 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5945 for (i
= 0; i
< nargs
; ++i
)
5947 parmtype
= TREE_VALUE (parmlist
);
5949 if (TYPE_REF_P (parmtype
))
5950 parmtype
= TREE_TYPE (parmtype
);
5951 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5952 && (same_type_ignoring_top_level_qualifiers_p
5953 (TREE_TYPE (args
[i
]), parmtype
)))
5956 parmlist
= TREE_CHAIN (parmlist
);
5959 /* No argument has an appropriate type, so remove this
5960 candidate function from the list. */
5963 *candp
= cand
->next
;
5969 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5976 /* For these, the built-in candidates set is empty
5977 [over.match.oper]/3. We don't want non-strict matches
5978 because exact matches are always possible with built-in
5979 operators. The built-in candidate set for COMPONENT_REF
5980 would be empty too, but since there are no such built-in
5981 operators, we accept non-strict matches for them. */
5990 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5995 case POSTINCREMENT_EXPR
:
5996 case POSTDECREMENT_EXPR
:
5997 /* Don't try anything fancy if we're not allowed to produce
5999 if (!(complain
& tf_error
))
6000 return error_mark_node
;
6002 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
6003 distinguish between prefix and postfix ++ and
6004 operator++() was used for both, so we allow this with
6008 const char *msg
= (flag_permissive
)
6009 ? G_("no %<%D(int)%> declared for postfix %qs,"
6010 " trying prefix operator instead")
6011 : G_("no %<%D(int)%> declared for postfix %qs");
6012 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
6015 if (!flag_permissive
)
6016 return error_mark_node
;
6018 if (code
== POSTINCREMENT_EXPR
)
6019 code
= PREINCREMENT_EXPR
;
6021 code
= PREDECREMENT_EXPR
;
6022 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
6023 NULL_TREE
, overload
, complain
);
6026 /* The caller will deal with these. */
6031 result_valid_p
= true;
6035 if (complain
& tf_error
)
6037 /* If one of the arguments of the operator represents
6038 an invalid use of member function pointer, try to report
6039 a meaningful error ... */
6040 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
6041 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
6042 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
6043 /* We displayed the error message. */;
6046 /* ... Otherwise, report the more generic
6047 "no matching operator found" error */
6048 auto_diagnostic_group d
;
6049 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
6050 print_z_candidates (loc
, candidates
);
6053 result
= error_mark_node
;
6059 cand
= tourney (candidates
, complain
);
6062 if (complain
& tf_error
)
6064 auto_diagnostic_group d
;
6065 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
6066 print_z_candidates (loc
, candidates
);
6068 result
= error_mark_node
;
6070 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
6073 *overload
= cand
->fn
;
6075 if (resolve_args (arglist
, complain
) == NULL
)
6076 result
= error_mark_node
;
6078 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6080 if (trivial_fn_p (cand
->fn
))
6081 /* There won't be a CALL_EXPR. */;
6082 else if (result
&& result
!= error_mark_node
)
6084 tree call
= extract_call_expr (result
);
6085 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
6087 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
6088 /* This prevents build_new_function_call from discarding this
6089 function during instantiation of the enclosing template. */
6090 KOENIG_LOOKUP_P (call
) = 1;
6092 /* Specify evaluation order as per P0145R2. */
6093 CALL_EXPR_ORDERED_ARGS (call
) = false;
6094 switch (op_is_ordered (code
))
6097 CALL_EXPR_REVERSE_ARGS (call
) = true;
6101 CALL_EXPR_ORDERED_ARGS (call
) = true;
6111 /* Give any warnings we noticed during overload resolution. */
6112 if (cand
->warnings
&& (complain
& tf_warning
))
6114 struct candidate_warning
*w
;
6115 for (w
= cand
->warnings
; w
; w
= w
->next
)
6116 joust (cand
, w
->loser
, 1, complain
);
6119 /* Check for comparison of different enum types. */
6128 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
6129 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
6130 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
6131 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
6132 && (complain
& tf_warning
))
6134 warning (OPT_Wenum_compare
,
6135 "comparison between %q#T and %q#T",
6136 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
6143 /* We need to strip any leading REF_BIND so that bitfields
6144 don't cause errors. This should not remove any important
6145 conversions, because builtins don't apply to class
6146 objects directly. */
6147 conv
= cand
->convs
[0];
6148 if (conv
->kind
== ck_ref_bind
)
6149 conv
= next_conversion (conv
);
6150 arg1
= convert_like (conv
, arg1
, complain
);
6154 conv
= cand
->convs
[1];
6155 if (conv
->kind
== ck_ref_bind
)
6156 conv
= next_conversion (conv
);
6158 arg2
= decay_conversion (arg2
, complain
);
6160 /* We need to call warn_logical_operator before
6161 converting arg2 to a boolean_type, but after
6162 decaying an enumerator to its value. */
6163 if (complain
& tf_warning
)
6164 warn_logical_operator (loc
, code
, boolean_type_node
,
6165 code_orig_arg1
, arg1
,
6166 code_orig_arg2
, arg2
);
6168 arg2
= convert_like (conv
, arg2
, complain
);
6172 conv
= cand
->convs
[2];
6173 if (conv
->kind
== ck_ref_bind
)
6174 conv
= next_conversion (conv
);
6175 convert_like (conv
, arg3
, complain
);
6181 user_defined_result_ready
:
6183 /* Free all the conversions we allocated. */
6184 obstack_free (&conversion_obstack
, p
);
6186 if (result
|| result_valid_p
)
6193 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6196 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6198 case TRUTH_ANDIF_EXPR
:
6199 case TRUTH_ORIF_EXPR
:
6200 case TRUTH_AND_EXPR
:
6202 if (complain
& tf_warning
)
6203 warn_logical_operator (loc
, code
, boolean_type_node
,
6204 code_orig_arg1
, arg1
,
6205 code_orig_arg2
, arg2
);
6213 if ((complain
& tf_warning
)
6214 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6215 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6216 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6217 if (complain
& tf_warning
&& warn_tautological_compare
)
6218 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6223 case TRUNC_DIV_EXPR
:
6228 case TRUNC_MOD_EXPR
:
6232 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6234 case UNARY_PLUS_EXPR
:
6237 case TRUTH_NOT_EXPR
:
6238 case PREINCREMENT_EXPR
:
6239 case POSTINCREMENT_EXPR
:
6240 case PREDECREMENT_EXPR
:
6241 case POSTDECREMENT_EXPR
:
6245 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6248 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6251 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6255 /* The caller will deal with these. */
6267 /* Wrapper for above. */
6270 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6271 tree arg1
, tree arg2
, tree arg3
,
6272 tree
*overload
, tsubst_flags_t complain
)
6275 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6276 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6277 overload
, complain
);
6278 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6282 /* CALL was returned by some call-building function; extract the actual
6283 CALL_EXPR from any bits that have been tacked on, e.g. by
6284 convert_from_reference. */
6287 extract_call_expr (tree call
)
6289 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6290 call
= TREE_OPERAND (call
, 1);
6291 if (REFERENCE_REF_P (call
))
6292 call
= TREE_OPERAND (call
, 0);
6293 if (TREE_CODE (call
) == TARGET_EXPR
)
6294 call
= TARGET_EXPR_INITIAL (call
);
6295 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6296 || TREE_CODE (call
) == AGGR_INIT_EXPR
6297 || call
== error_mark_node
);
6301 /* Returns true if FN has two parameters, of which the second has type
6305 second_parm_is_size_t (tree fn
)
6307 tree t
= FUNCTION_ARG_CHAIN (fn
);
6308 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6311 if (t
== void_list_node
)
6316 /* True if T, an allocation function, has std::align_val_t as its second
6320 aligned_allocation_fn_p (tree t
)
6322 if (!aligned_new_threshold
)
6325 tree a
= FUNCTION_ARG_CHAIN (t
);
6326 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6329 /* True if T is std::destroying_delete_t. */
6332 std_destroying_delete_t_p (tree t
)
6334 return (TYPE_CONTEXT (t
) == std_node
6335 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6338 /* A deallocation function with at least two parameters whose second parameter
6339 type is of type std::destroying_delete_t is a destroying operator delete. A
6340 destroying operator delete shall be a class member function named operator
6341 delete. [ Note: Array deletion cannot use a destroying operator
6342 delete. --end note ] */
6345 destroying_delete_p (tree t
)
6347 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6348 if (!a
|| !TREE_CHAIN (a
))
6350 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6351 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6361 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6362 function (3.7.4.2 [basic.stc.dynamic.deallocation]). If so, and DI is
6363 non-null, also set *DI. */
6366 usual_deallocation_fn_p (tree t
, dealloc_info
*di
)
6368 if (di
) *di
= dealloc_info();
6370 /* A template instance is never a usual deallocation function,
6371 regardless of its signature. */
6372 if (TREE_CODE (t
) == TEMPLATE_DECL
6373 || primary_template_specialization_p (t
))
6376 /* A usual deallocation function is a deallocation function whose parameters
6378 - optionally, a parameter of type std::destroying_delete_t, then
6379 - optionally, a parameter of type std::size_t, then
6380 - optionally, a parameter of type std::align_val_t. */
6381 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6382 tree chain
= FUNCTION_ARG_CHAIN (t
);
6383 if (chain
&& destroying_delete_p (t
))
6385 if (di
) di
->destroying
= TREE_VALUE (chain
);
6386 chain
= TREE_CHAIN (chain
);
6389 && (!global
|| flag_sized_deallocation
)
6390 && same_type_p (TREE_VALUE (chain
), size_type_node
))
6392 if (di
) di
->sized
= true;
6393 chain
= TREE_CHAIN (chain
);
6395 if (chain
&& aligned_new_threshold
6396 && same_type_p (TREE_VALUE (chain
), align_type_node
))
6398 if (di
) di
->aligned
= true;
6399 chain
= TREE_CHAIN (chain
);
6401 return (chain
== void_list_node
);
6404 /* Just return whether FN is a usual deallocation function. */
6407 usual_deallocation_fn_p (tree fn
)
6409 return usual_deallocation_fn_p (fn
, NULL
);
6412 /* Build a call to operator delete. This has to be handled very specially,
6413 because the restrictions on what signatures match are different from all
6414 other call instances. For a normal delete, only a delete taking (void *)
6415 or (void *, size_t) is accepted. For a placement delete, only an exact
6416 match with the placement new is accepted.
6418 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6419 ADDR is the pointer to be deleted.
6420 SIZE is the size of the memory block to be deleted.
6421 GLOBAL_P is true if the delete-expression should not consider
6422 class-specific delete operators.
6423 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6425 If this call to "operator delete" is being generated as part to
6426 deallocate memory allocated via a new-expression (as per [expr.new]
6427 which requires that if the initialization throws an exception then
6428 we call a deallocation function), then ALLOC_FN is the allocation
6432 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6433 bool global_p
, tree placement
,
6434 tree alloc_fn
, tsubst_flags_t complain
)
6436 tree fn
= NULL_TREE
;
6437 tree fns
, fnname
, type
, t
;
6438 dealloc_info di_fn
= { };
6440 if (addr
== error_mark_node
)
6441 return error_mark_node
;
6443 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6445 fnname
= ovl_op_identifier (false, code
);
6447 if (CLASS_TYPE_P (type
)
6448 && COMPLETE_TYPE_P (complete_type (type
))
6452 If the result of the lookup is ambiguous or inaccessible, or if
6453 the lookup selects a placement deallocation function, the
6454 program is ill-formed.
6456 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6458 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6459 if (fns
== error_mark_node
)
6460 return error_mark_node
;
6465 if (fns
== NULL_TREE
)
6466 fns
= lookup_name_nonclass (fnname
);
6468 /* Strip const and volatile from addr. */
6470 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6474 /* "A declaration of a placement deallocation function matches the
6475 declaration of a placement allocation function if it has the same
6476 number of parameters and, after parameter transformations (8.3.5),
6477 all parameter types except the first are identical."
6479 So we build up the function type we want and ask instantiate_type
6480 to get it for us. */
6481 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6482 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6483 t
= build_function_type (void_type_node
, t
);
6485 fn
= instantiate_type (t
, fns
, tf_none
);
6486 if (fn
== error_mark_node
)
6489 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6491 /* "If the lookup finds the two-parameter form of a usual deallocation
6492 function (3.7.4.2) and that function, considered as a placement
6493 deallocation function, would have been selected as a match for the
6494 allocation function, the program is ill-formed." */
6495 if (second_parm_is_size_t (fn
))
6497 const char *const msg1
6498 = G_("exception cleanup for this placement new selects "
6499 "non-placement %<operator delete%>");
6500 const char *const msg2
6501 = G_("%qD is a usual (non-placement) deallocation "
6502 "function in C++14 (or with %<-fsized-deallocation%>)");
6504 /* But if the class has an operator delete (void *), then that is
6505 the usual deallocation function, so we shouldn't complain
6506 about using the operator delete (void *, size_t). */
6507 if (DECL_CLASS_SCOPE_P (fn
))
6508 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6512 if (usual_deallocation_fn_p (elt
)
6513 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6516 /* Before C++14 a two-parameter global deallocation function is
6517 always a placement deallocation function, but warn if
6519 else if (!flag_sized_deallocation
)
6521 if (complain
& tf_warning
)
6523 auto_diagnostic_group d
;
6524 if (warning (OPT_Wc__14_compat
, msg1
))
6525 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6530 if (complain
& tf_warning_or_error
)
6532 auto_diagnostic_group d
;
6533 if (permerror (input_location
, msg1
))
6535 /* Only mention C++14 for namespace-scope delete. */
6536 if (DECL_NAMESPACE_SCOPE_P (fn
))
6537 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6539 inform (DECL_SOURCE_LOCATION (fn
),
6540 "%qD is a usual (non-placement) deallocation "
6545 return error_mark_node
;
6550 /* "Any non-placement deallocation function matches a non-placement
6551 allocation function. If the lookup finds a single matching
6552 deallocation function, that function will be called; otherwise, no
6553 deallocation function will be called." */
6554 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6557 dealloc_info di_elt
;
6558 if (usual_deallocation_fn_p (elt
, &di_elt
))
6567 /* -- If any of the deallocation functions is a destroying
6568 operator delete, all deallocation functions that are not
6569 destroying operator deletes are eliminated from further
6571 if (di_elt
.destroying
!= di_fn
.destroying
)
6573 if (di_elt
.destroying
)
6581 /* -- If the type has new-extended alignment, a function with a
6582 parameter of type std::align_val_t is preferred; otherwise a
6583 function without such a parameter is preferred. If exactly one
6584 preferred function is found, that function is selected and the
6585 selection process terminates. If more than one preferred
6586 function is found, all non-preferred functions are eliminated
6587 from further consideration. */
6588 if (aligned_new_threshold
)
6590 bool want_align
= type_has_new_extended_alignment (type
);
6591 if (di_elt
.aligned
!= di_fn
.aligned
)
6593 if (want_align
== di_elt
.aligned
)
6602 /* -- If the deallocation functions have class scope, the one
6603 without a parameter of type std::size_t is selected. */
6605 if (DECL_CLASS_SCOPE_P (fn
))
6608 /* -- If the type is complete and if, for the second alternative
6609 (delete array) only, the operand is a pointer to a class type
6610 with a non-trivial destructor or a (possibly multi-dimensional)
6611 array thereof, the function with a parameter of type std::size_t
6614 -- Otherwise, it is unspecified whether a deallocation function
6615 with a parameter of type std::size_t is selected. */
6618 want_size
= COMPLETE_TYPE_P (type
);
6619 if (code
== VEC_DELETE_EXPR
6620 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6621 /* We need a cookie to determine the array size. */
6624 gcc_assert (di_fn
.sized
!= di_elt
.sized
);
6625 if (want_size
== di_elt
.sized
)
6633 /* If we have a matching function, call it. */
6636 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6638 /* If the FN is a member function, make sure that it is
6640 if (BASELINK_P (fns
))
6641 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6644 /* Core issue 901: It's ok to new a type with deleted delete. */
6645 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6650 /* The placement args might not be suitable for overload
6651 resolution at this point, so build the call directly. */
6652 int nargs
= call_expr_nargs (placement
);
6653 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6656 for (i
= 1; i
< nargs
; i
++)
6657 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6658 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6659 return error_mark_node
;
6660 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6664 tree destroying
= di_fn
.destroying
;
6667 /* Strip const and volatile from addr but retain the type of the
6669 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6670 rtype
= cv_unqualified (rtype
);
6671 rtype
= TYPE_POINTER_TO (rtype
);
6672 addr
= cp_convert (rtype
, oaddr
, complain
);
6673 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6679 args
->quick_push (addr
);
6681 args
->quick_push (destroying
);
6683 args
->quick_push (size
);
6686 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6687 args
->quick_push (al
);
6689 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6696 If no unambiguous matching deallocation function can be found,
6697 propagating the exception does not cause the object's memory to
6701 if ((complain
& tf_warning
)
6703 warning (0, "no corresponding deallocation function for %qD",
6708 if (complain
& tf_error
)
6709 error ("no suitable %<operator %s%> for %qT",
6710 OVL_OP_INFO (false, code
)->name
, type
);
6711 return error_mark_node
;
6714 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6717 If ISSUE_ERROR is true, then issue an error about the
6718 access, followed by a note showing the declaration.
6719 Otherwise, just show the note. */
6722 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6724 if (TREE_PRIVATE (decl
))
6727 error ("%q#D is private within this context", diag_decl
);
6728 inform (DECL_SOURCE_LOCATION (diag_decl
),
6729 "declared private here");
6731 else if (TREE_PROTECTED (decl
))
6734 error ("%q#D is protected within this context", diag_decl
);
6735 inform (DECL_SOURCE_LOCATION (diag_decl
),
6736 "declared protected here");
6741 error ("%q#D is inaccessible within this context", diag_decl
);
6742 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6746 /* If the current scope isn't allowed to access DECL along
6747 BASETYPE_PATH, give an error. The most derived class in
6748 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6749 the declaration to use in the error diagnostic. */
6752 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6753 tsubst_flags_t complain
, access_failure_info
*afi
)
6755 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6757 if (flag_new_inheriting_ctors
6758 && DECL_INHERITED_CTOR (decl
))
6760 /* 7.3.3/18: The additional constructors are accessible if they would be
6761 accessible when used to construct an object of the corresponding base
6763 decl
= strip_inheriting_ctors (decl
);
6764 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6765 ba_any
, NULL
, complain
);
6768 if (!accessible_p (basetype_path
, decl
, true))
6770 if (flag_new_inheriting_ctors
)
6771 diag_decl
= strip_inheriting_ctors (diag_decl
);
6772 if (complain
& tf_error
)
6773 complain_about_access (decl
, diag_decl
, true);
6775 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6782 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6783 bitwise or of LOOKUP_* values. If any errors are warnings are
6784 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6785 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6789 build_temp (tree expr
, tree type
, int flags
,
6790 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6794 *diagnostic_kind
= DK_UNSPECIFIED
;
6796 /* If the source is a packed field, calling the copy constructor will require
6797 binding the field to the reference parameter to the copy constructor, and
6798 we'll end up with an infinite loop. If we can use a bitwise copy, then
6800 if ((lvalue_kind (expr
) & clk_packed
)
6801 && CLASS_TYPE_P (TREE_TYPE (expr
))
6802 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6803 return get_target_expr_sfinae (expr
, complain
);
6805 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6806 releasing_vec
args (make_tree_vector_single (expr
));
6807 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6808 &args
, type
, flags
, complain
);
6809 if (warningcount
+ werrorcount
> savew
)
6810 *diagnostic_kind
= DK_WARNING
;
6811 else if (errorcount
> savee
)
6812 *diagnostic_kind
= DK_ERROR
;
6816 /* Get any location for EXPR, falling back to input_location.
6818 If the result is in a system header and is the virtual location for
6819 a token coming from the expansion of a macro, unwind it to the
6820 location of the expansion point of the macro (e.g. to avoid the
6821 diagnostic being suppressed for expansions of NULL where "NULL" is
6822 in a system header). */
6825 get_location_for_expr_unwinding_for_system_header (tree expr
)
6827 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6828 loc
= expansion_point_location_if_in_system_header (loc
);
6832 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6833 Also handle a subset of zero as null warnings.
6834 EXPR is implicitly converted to type TOTYPE.
6835 FN and ARGNUM are used for diagnostics. */
6838 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6840 /* Issue warnings about peculiar, but valid, uses of NULL. */
6841 if (TREE_CODE (totype
) != BOOLEAN_TYPE
6842 && ARITHMETIC_TYPE_P (totype
)
6843 && null_node_p (expr
))
6845 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6848 auto_diagnostic_group d
;
6849 if (warning_at (loc
, OPT_Wconversion_null
,
6850 "passing NULL to non-pointer argument %P of %qD",
6852 inform (get_fndecl_argument_location (fn
, argnum
),
6856 warning_at (loc
, OPT_Wconversion_null
,
6857 "converting to non-pointer type %qT from NULL", totype
);
6860 /* Issue warnings if "false" is converted to a NULL pointer */
6861 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6862 && TYPE_PTR_P (totype
))
6864 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6867 auto_diagnostic_group d
;
6868 if (warning_at (loc
, OPT_Wconversion_null
,
6869 "converting %<false%> to pointer type for argument "
6870 "%P of %qD", argnum
, fn
))
6871 inform (get_fndecl_argument_location (fn
, argnum
),
6875 warning_at (loc
, OPT_Wconversion_null
,
6876 "converting %<false%> to pointer type %qT", totype
);
6878 /* Handle zero as null pointer warnings for cases other
6879 than EQ_EXPR and NE_EXPR */
6880 else if ((TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
))
6881 && null_ptr_cst_p (expr
))
6883 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6884 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6888 /* We gave a diagnostic during a conversion. If this was in the second
6889 standard conversion sequence of a user-defined conversion sequence, say
6890 which user-defined conversion. */
6893 maybe_print_user_conv_context (conversion
*convs
)
6895 if (convs
->user_conv_p
)
6896 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6897 if (t
->kind
== ck_user
)
6899 print_z_candidate (0, N_(" after user-defined conversion:"),
6905 /* Locate the parameter with the given index within FNDECL.
6906 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6907 Return the location of the FNDECL itself if there are problems. */
6910 get_fndecl_argument_location (tree fndecl
, int argnum
)
6912 /* The locations of implicitly-declared functions are likely to be
6913 more meaningful than those of their parameters. */
6914 if (DECL_ARTIFICIAL (fndecl
))
6915 return DECL_SOURCE_LOCATION (fndecl
);
6920 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6921 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6922 i
< argnum
&& param
;
6923 i
++, param
= TREE_CHAIN (param
))
6926 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6927 return the location of FNDECL. */
6929 return DECL_SOURCE_LOCATION (fndecl
);
6931 return DECL_SOURCE_LOCATION (param
);
6934 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6935 within its declaration (or the fndecl itself if something went
6939 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6942 inform (get_fndecl_argument_location (fn
, argnum
),
6943 " initializing argument %P of %qD", argnum
, fn
);
6946 /* Perform the conversions in CONVS on the expression EXPR. FN and
6947 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6948 indicates the `this' argument of a method. INNER is nonzero when
6949 being called to continue a conversion chain. It is negative when a
6950 reference binding will be applied, positive otherwise. If
6951 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6952 conversions will be emitted if appropriate. If C_CAST_P is true,
6953 this conversion is coming from a C-style cast; in that case,
6954 conversions to inaccessible bases are permitted. */
6957 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6958 bool issue_conversion_warnings
,
6959 bool c_cast_p
, tsubst_flags_t complain
)
6961 tree totype
= convs
->type
;
6962 diagnostic_t diag_kind
;
6964 location_t loc
= cp_expr_loc_or_input_loc (expr
);
6966 if (convs
->bad_p
&& !(complain
& tf_error
))
6967 return error_mark_node
;
6970 && convs
->kind
!= ck_user
6971 && convs
->kind
!= ck_list
6972 && convs
->kind
!= ck_ambig
6973 && (convs
->kind
!= ck_ref_bind
6974 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6975 && (convs
->kind
!= ck_rvalue
6976 || SCALAR_TYPE_P (totype
))
6977 && convs
->kind
!= ck_base
)
6979 bool complained
= false;
6980 conversion
*t
= convs
;
6982 /* Give a helpful error if this is bad because of excess braces. */
6983 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6984 && SCALAR_TYPE_P (totype
)
6985 && CONSTRUCTOR_NELTS (expr
) > 0
6986 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6988 complained
= permerror (loc
, "too many braces around initializer "
6990 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6991 && CONSTRUCTOR_NELTS (expr
) == 1)
6992 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6995 /* Give a helpful error if this is bad because a conversion to bool
6996 from std::nullptr_t requires direct-initialization. */
6997 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6998 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6999 complained
= permerror (loc
, "converting to %qH from %qI requires "
7000 "direct-initialization",
7001 totype
, TREE_TYPE (expr
));
7003 for (; t
; t
= next_conversion (t
))
7005 if (t
->kind
== ck_user
&& t
->cand
->reason
)
7007 auto_diagnostic_group d
;
7008 complained
= permerror (loc
, "invalid user-defined conversion "
7009 "from %qH to %qI", TREE_TYPE (expr
),
7012 print_z_candidate (loc
, N_("candidate is:"), t
->cand
);
7013 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7014 /*issue_conversion_warnings=*/false,
7017 if (convs
->kind
== ck_ref_bind
)
7018 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
7019 LOOKUP_NORMAL
, NULL_TREE
,
7022 expr
= cp_convert (totype
, expr
, complain
);
7024 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7027 else if (t
->kind
== ck_user
|| !t
->bad_p
)
7029 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7030 /*issue_conversion_warnings=*/false,
7035 else if (t
->kind
== ck_ambig
)
7036 return convert_like_real (t
, expr
, fn
, argnum
,
7037 /*issue_conversion_warnings=*/false,
7040 else if (t
->kind
== ck_identity
)
7045 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
7046 gcc_rich_location
richloc (loc
, &label
);
7047 complained
= permerror (&richloc
,
7048 "invalid conversion from %qH to %qI",
7049 TREE_TYPE (expr
), totype
);
7052 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7054 return cp_convert (totype
, expr
, complain
);
7057 if (issue_conversion_warnings
&& (complain
& tf_warning
))
7058 conversion_null_warnings (totype
, expr
, fn
, argnum
);
7060 switch (convs
->kind
)
7064 struct z_candidate
*cand
= convs
->cand
;
7067 /* We chose the surrogate function from add_conv_candidate, now we
7068 actually need to build the conversion. */
7069 cand
= build_user_type_conversion_1 (totype
, expr
,
7070 LOOKUP_NO_CONVERSION
, complain
);
7072 tree convfn
= cand
->fn
;
7074 /* When converting from an init list we consider explicit
7075 constructors, but actually trying to call one is an error. */
7076 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
7077 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
7078 /* Unless this is for direct-list-initialization. */
7079 && (!CONSTRUCTOR_IS_DIRECT_INIT (expr
) || convs
->need_temporary_p
)
7080 /* And in C++98 a default constructor can't be explicit. */
7081 && cxx_dialect
>= cxx11
)
7083 if (!(complain
& tf_error
))
7084 return error_mark_node
;
7085 location_t loc
= location_of (expr
);
7086 if (CONSTRUCTOR_NELTS (expr
) == 0
7087 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
7089 auto_diagnostic_group d
;
7090 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
7091 "would use explicit constructor %qD",
7093 inform (loc
, "in C++11 and above a default constructor "
7097 error ("converting to %qT from initializer list would use "
7098 "explicit constructor %qD", totype
, convfn
);
7101 /* If we're initializing from {}, it's value-initialization. */
7102 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7103 && CONSTRUCTOR_NELTS (expr
) == 0
7104 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
)
7105 && !processing_template_decl
)
7107 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
7108 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
7109 return error_mark_node
;
7110 expr
= build_value_init (totype
, complain
);
7111 expr
= get_target_expr_sfinae (expr
, complain
);
7112 if (expr
!= error_mark_node
)
7114 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7115 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
7120 /* We don't know here whether EXPR is being used as an lvalue or
7121 rvalue, but we know it's read. */
7122 mark_exp_read (expr
);
7124 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
7126 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
7129 /* If this is a constructor or a function returning an aggr type,
7130 we need to build up a TARGET_EXPR. */
7131 if (DECL_CONSTRUCTOR_P (convfn
))
7133 expr
= build_cplus_new (totype
, expr
, complain
);
7135 /* Remember that this was list-initialization. */
7136 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
7137 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7143 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
7145 int nelts
= CONSTRUCTOR_NELTS (expr
);
7147 expr
= build_value_init (totype
, complain
);
7148 else if (nelts
== 1)
7149 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7153 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7154 /*read_p=*/true, UNKNOWN_LOCATION
,
7155 /*reject_builtin=*/true);
7157 if (type_unknown_p (expr
))
7158 expr
= instantiate_type (totype
, expr
, complain
);
7159 if (expr
== null_node
7160 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7161 /* If __null has been converted to an integer type, we do not want to
7162 continue to warn about uses of EXPR as an integer, rather than as a
7164 expr
= build_int_cst (totype
, 0);
7167 /* We leave bad_p off ck_ambig because overload resolution considers
7168 it valid, it just fails when we try to perform it. So we need to
7169 check complain here, too. */
7170 if (complain
& tf_error
)
7172 /* Call build_user_type_conversion again for the error. */
7173 int flags
= (convs
->need_temporary_p
7174 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7175 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7176 gcc_assert (seen_error ());
7177 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7179 return error_mark_node
;
7183 /* Conversion to std::initializer_list<T>. */
7184 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7185 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7190 tree val
; unsigned ix
;
7192 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7194 /* Convert all the elements. */
7195 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7197 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
,
7198 argnum
, false, false, complain
);
7199 if (sub
== error_mark_node
)
7201 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7202 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7203 return error_mark_node
;
7204 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
),
7206 if (!TREE_CONSTANT (sub
))
7207 TREE_CONSTANT (new_ctor
) = false;
7209 /* Build up the array. */
7210 elttype
= cp_build_qualified_type
7211 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7212 array
= build_array_of_n_type (elttype
, len
);
7213 array
= finish_compound_literal (array
, new_ctor
, complain
);
7214 /* Take the address explicitly rather than via decay_conversion
7215 to avoid the error about taking the address of a temporary. */
7216 array
= cp_build_addr_expr (array
, complain
);
7219 array
= nullptr_node
;
7221 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7222 if (array
== error_mark_node
)
7223 return error_mark_node
;
7225 /* Build up the initializer_list object. Note: fail gracefully
7226 if the object cannot be completed because, for example, no
7227 definition is provided (c++/80956). */
7228 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7230 return error_mark_node
;
7231 tree field
= next_initializable_field (TYPE_FIELDS (totype
));
7232 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7233 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7234 field
= next_initializable_field (DECL_CHAIN (field
));
7235 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7236 tree new_ctor
= build_constructor (totype
, vec
);
7237 return get_target_expr_sfinae (new_ctor
, complain
);
7241 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7243 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7244 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7245 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7247 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7249 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7252 expr
= reshape_init (totype
, expr
, complain
);
7253 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7255 if (expr
!= error_mark_node
)
7256 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7263 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7264 convs
->kind
== ck_ref_bind
7265 ? issue_conversion_warnings
: false,
7266 c_cast_p
, complain
);
7267 if (expr
== error_mark_node
)
7268 return error_mark_node
;
7270 switch (convs
->kind
)
7273 expr
= decay_conversion (expr
, complain
);
7274 if (expr
== error_mark_node
)
7276 if (complain
& tf_error
)
7278 auto_diagnostic_group d
;
7279 maybe_print_user_conv_context (convs
);
7280 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7282 return error_mark_node
;
7285 if (! MAYBE_CLASS_TYPE_P (totype
))
7288 /* Don't introduce copies when passing arguments along to the inherited
7290 if (current_function_decl
7291 && flag_new_inheriting_ctors
7292 && DECL_INHERITED_CTOR (current_function_decl
))
7295 if (TREE_CODE (expr
) == TARGET_EXPR
7296 && TARGET_EXPR_LIST_INIT_P (expr
))
7297 /* Copy-list-initialization doesn't actually involve a copy. */
7302 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7304 /* We are going to bind a reference directly to a base-class
7305 subobject of EXPR. */
7306 /* Build an expression for `*((base*) &expr)'. */
7307 expr
= convert_to_base (expr
, totype
,
7308 !c_cast_p
, /*nonnull=*/true, complain
);
7312 /* Copy-initialization where the cv-unqualified version of the source
7313 type is the same class as, or a derived class of, the class of the
7314 destination [is treated as direct-initialization]. [dcl.init] */
7315 flags
= LOOKUP_NORMAL
;
7316 if (convs
->user_conv_p
)
7317 /* This conversion is being done in the context of a user-defined
7318 conversion (i.e. the second step of copy-initialization), so
7319 don't allow any more. */
7320 flags
|= LOOKUP_NO_CONVERSION
;
7322 flags
|= LOOKUP_ONLYCONVERTING
;
7323 if (convs
->rvaluedness_matches_p
)
7324 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7325 flags
|= LOOKUP_PREFER_RVALUE
;
7326 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7327 if (diag_kind
&& complain
)
7329 auto_diagnostic_group d
;
7330 maybe_print_user_conv_context (convs
);
7331 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7334 return build_cplus_new (totype
, expr
, complain
);
7338 tree ref_type
= totype
;
7340 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7342 tree extype
= TREE_TYPE (expr
);
7343 auto_diagnostic_group d
;
7344 if (TYPE_REF_IS_RVALUE (ref_type
)
7346 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7347 "lvalue of type %qI", totype
, extype
);
7348 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7349 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7350 error_at (loc
, "cannot bind non-const lvalue reference of "
7351 "type %qH to an rvalue of type %qI", totype
, extype
);
7352 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7353 error_at (loc
, "binding reference of type %qH to %qI "
7354 "discards qualifiers", totype
, extype
);
7357 maybe_print_user_conv_context (convs
);
7358 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7360 return error_mark_node
;
7363 /* If necessary, create a temporary.
7365 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7366 that need temporaries, even when their types are reference
7367 compatible with the type of reference being bound, so the
7368 upcoming call to cp_build_addr_expr doesn't fail. */
7369 if (convs
->need_temporary_p
7370 || TREE_CODE (expr
) == CONSTRUCTOR
7371 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7373 /* Otherwise, a temporary of type "cv1 T1" is created and
7374 initialized from the initializer expression using the rules
7375 for a non-reference copy-initialization (8.5). */
7377 tree type
= TREE_TYPE (ref_type
);
7378 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7380 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7381 (type
, next_conversion (convs
)->type
));
7382 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7383 && !TYPE_REF_IS_RVALUE (ref_type
))
7385 /* If the reference is volatile or non-const, we
7386 cannot create a temporary. */
7387 if (lvalue
& clk_bitfield
)
7388 error_at (loc
, "cannot bind bit-field %qE to %qT",
7390 else if (lvalue
& clk_packed
)
7391 error_at (loc
, "cannot bind packed field %qE to %qT",
7394 error_at (loc
, "cannot bind rvalue %qE to %qT",
7396 return error_mark_node
;
7398 /* If the source is a packed field, and we must use a copy
7399 constructor, then building the target expr will require
7400 binding the field to the reference parameter to the
7401 copy constructor, and we'll end up with an infinite
7402 loop. If we can use a bitwise copy, then we'll be
7404 if ((lvalue
& clk_packed
)
7405 && CLASS_TYPE_P (type
)
7406 && type_has_nontrivial_copy_init (type
))
7408 error_at (loc
, "cannot bind packed field %qE to %qT",
7410 return error_mark_node
;
7412 if (lvalue
& clk_bitfield
)
7414 expr
= convert_bitfield_to_declared_type (expr
);
7415 expr
= fold_convert (type
, expr
);
7417 expr
= build_target_expr_with_type (expr
, type
, complain
);
7420 /* Take the address of the thing to which we will bind the
7422 expr
= cp_build_addr_expr (expr
, complain
);
7423 if (expr
== error_mark_node
)
7424 return error_mark_node
;
7426 /* Convert it to a pointer to the type referred to by the
7427 reference. This will adjust the pointer if a derived to
7428 base conversion is being performed. */
7429 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7431 /* Convert the pointer to the desired reference type. */
7432 return build_nop (ref_type
, expr
);
7436 return decay_conversion (expr
, complain
);
7439 /* ??? Should the address of a transaction-safe pointer point to the TM
7440 clone, and this conversion look up the primary function? */
7441 return build_nop (totype
, expr
);
7444 /* Warn about deprecated conversion if appropriate. */
7445 if (complain
& tf_warning
)
7446 string_conv_p (totype
, expr
, 1);
7451 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7452 /*nonnull=*/false, complain
);
7453 return build_nop (totype
, expr
);
7456 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7457 c_cast_p
, complain
);
7463 if (convs
->check_narrowing
7464 && !check_narrowing (totype
, expr
, complain
,
7465 convs
->check_narrowing_const_only
))
7466 return error_mark_node
;
7468 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7469 if (issue_conversion_warnings
)
7470 expr
= cp_convert_and_check (totype
, expr
, complain
);
7472 expr
= cp_convert (totype
, expr
, complain
);
7477 /* ARG is being passed to a varargs function. Perform any conversions
7478 required. Return the converted value. */
7481 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7484 location_t loc
= cp_expr_loc_or_input_loc (arg
);
7488 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7489 standard conversions are performed. */
7490 arg
= decay_conversion (arg
, complain
);
7491 arg_type
= TREE_TYPE (arg
);
7494 If the argument has integral or enumeration type that is subject
7495 to the integral promotions (_conv.prom_), or a floating-point
7496 type that is subject to the floating-point promotion
7497 (_conv.fpprom_), the value of the argument is converted to the
7498 promoted type before the call. */
7499 if (TREE_CODE (arg_type
) == REAL_TYPE
7500 && (TYPE_PRECISION (arg_type
)
7501 < TYPE_PRECISION (double_type_node
))
7502 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7504 if ((complain
& tf_warning
)
7505 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7506 warning_at (loc
, OPT_Wdouble_promotion
,
7507 "implicit conversion from %qH to %qI when passing "
7508 "argument to function",
7509 arg_type
, double_type_node
);
7510 arg
= convert_to_real_nofold (double_type_node
, arg
);
7512 else if (NULLPTR_TYPE_P (arg_type
))
7513 arg
= null_pointer_node
;
7514 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7516 if (SCOPED_ENUM_P (arg_type
))
7518 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7520 prom
= cp_perform_integral_promotions (prom
, complain
);
7521 if (abi_version_crosses (6)
7522 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7523 && (complain
& tf_warning
))
7524 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through %<...%>"
7525 "as %qT before %<-fabi-version=6%>, %qT after",
7527 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7528 if (!abi_version_at_least (6))
7532 arg
= cp_perform_integral_promotions (arg
, complain
);
7535 arg
= require_complete_type_sfinae (arg
, complain
);
7536 arg_type
= TREE_TYPE (arg
);
7538 if (arg
!= error_mark_node
7539 /* In a template (or ill-formed code), we can have an incomplete type
7540 even after require_complete_type_sfinae, in which case we don't know
7541 whether it has trivial copy or not. */
7542 && COMPLETE_TYPE_P (arg_type
)
7543 && !cp_unevaluated_operand
)
7545 /* [expr.call] 5.2.2/7:
7546 Passing a potentially-evaluated argument of class type (Clause 9)
7547 with a non-trivial copy constructor or a non-trivial destructor
7548 with no corresponding parameter is conditionally-supported, with
7549 implementation-defined semantics.
7551 We support it as pass-by-invisible-reference, just like a normal
7554 If the call appears in the context of a sizeof expression,
7555 it is not potentially-evaluated. */
7556 if (type_has_nontrivial_copy_init (arg_type
)
7557 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7559 arg
= force_rvalue (arg
, complain
);
7560 if (complain
& tf_warning
)
7561 warning (OPT_Wconditionally_supported
,
7562 "passing objects of non-trivially-copyable "
7563 "type %q#T through %<...%> is conditionally supported",
7565 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7567 /* Build up a real lvalue-to-rvalue conversion in case the
7568 copy constructor is trivial but not callable. */
7569 else if (CLASS_TYPE_P (arg_type
))
7570 force_rvalue (arg
, complain
);
7577 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7580 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7582 if (processing_template_decl
)
7584 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7585 SET_EXPR_LOCATION (r
, loc
);
7589 type
= complete_type_or_else (type
, NULL_TREE
);
7591 if (expr
== error_mark_node
|| !type
)
7592 return error_mark_node
;
7594 expr
= mark_lvalue_use (expr
);
7596 if (TYPE_REF_P (type
))
7598 error ("cannot receive reference type %qT through %<...%>", type
);
7599 return error_mark_node
;
7602 if (type_has_nontrivial_copy_init (type
)
7603 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7605 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7606 it as pass by invisible reference. */
7607 warning_at (loc
, OPT_Wconditionally_supported
,
7608 "receiving objects of non-trivially-copyable type %q#T "
7609 "through %<...%> is conditionally-supported", type
);
7611 tree ref
= cp_build_reference_type (type
, false);
7612 expr
= build_va_arg (loc
, expr
, ref
);
7613 return convert_from_reference (expr
);
7616 tree ret
= build_va_arg (loc
, expr
, type
);
7617 if (CLASS_TYPE_P (type
))
7618 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7619 know how to handle it. */
7620 ret
= get_target_expr (ret
);
7624 /* TYPE has been given to va_arg. Apply the default conversions which
7625 would have happened when passed via ellipsis. Return the promoted
7626 type, or the passed type if there is no change. */
7629 cxx_type_promotes_to (tree type
)
7633 /* Perform the array-to-pointer and function-to-pointer
7635 type
= type_decays_to (type
);
7637 promote
= type_promotes_to (type
);
7638 if (same_type_p (type
, promote
))
7644 /* ARG is a default argument expression being passed to a parameter of
7645 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7646 zero-based argument number. Do any required conversions. Return
7647 the converted value. */
7649 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7651 push_defarg_context (tree fn
)
7652 { vec_safe_push (default_arg_context
, fn
); }
7655 pop_defarg_context (void)
7656 { default_arg_context
->pop (); }
7659 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7660 tsubst_flags_t complain
)
7665 /* See through clones. */
7666 fn
= DECL_ORIGIN (fn
);
7667 /* And inheriting ctors. */
7668 if (flag_new_inheriting_ctors
)
7669 fn
= strip_inheriting_ctors (fn
);
7671 /* Detect recursion. */
7672 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7675 if (complain
& tf_error
)
7676 error ("recursive evaluation of default argument for %q#D", fn
);
7677 return error_mark_node
;
7680 /* If the ARG is an unparsed default argument expression, the
7681 conversion cannot be performed. */
7682 if (TREE_CODE (arg
) == DEFERRED_PARSE
)
7684 if (complain
& tf_error
)
7685 error ("call to %qD uses the default argument for parameter %P, which "
7686 "is not yet defined", fn
, parmnum
);
7687 return error_mark_node
;
7690 push_defarg_context (fn
);
7692 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7693 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7699 The names in the expression are bound, and the semantic
7700 constraints are checked, at the point where the default
7701 expressions appears.
7703 we must not perform access checks here. */
7704 push_deferring_access_checks (dk_no_check
);
7705 /* We must make a copy of ARG, in case subsequent processing
7706 alters any part of it. */
7707 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7709 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7710 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7712 arg
= convert_for_arg_passing (type
, arg
, complain
);
7713 pop_deferring_access_checks();
7715 pop_defarg_context ();
7720 /* Returns the type which will really be used for passing an argument of
7724 type_passed_as (tree type
)
7726 /* Pass classes with copy ctors by invisible reference. */
7727 if (TREE_ADDRESSABLE (type
))
7729 type
= build_reference_type (type
);
7730 /* There are no other pointers to this temporary. */
7731 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7733 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7734 && INTEGRAL_TYPE_P (type
)
7735 && COMPLETE_TYPE_P (type
)
7736 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7737 type
= integer_type_node
;
7742 /* Actually perform the appropriate conversion. */
7745 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7749 /* If VAL is a bitfield, then -- since it has already been converted
7750 to TYPE -- it cannot have a precision greater than TYPE.
7752 If it has a smaller precision, we must widen it here. For
7753 example, passing "int f:3;" to a function expecting an "int" will
7754 not result in any conversion before this point.
7756 If the precision is the same we must not risk widening. For
7757 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7758 often have type "int", even though the C++ type for the field is
7759 "long long". If the value is being passed to a function
7760 expecting an "int", then no conversions will be required. But,
7761 if we call convert_bitfield_to_declared_type, the bitfield will
7762 be converted to "long long". */
7763 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7765 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7766 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7768 if (val
== error_mark_node
)
7770 /* Pass classes with copy ctors by invisible reference. */
7771 else if (TREE_ADDRESSABLE (type
))
7772 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7773 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7774 && INTEGRAL_TYPE_P (type
)
7775 && COMPLETE_TYPE_P (type
)
7776 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7777 val
= cp_perform_integral_promotions (val
, complain
);
7778 if (complain
& tf_warning
)
7780 if (warn_suggest_attribute_format
)
7782 tree rhstype
= TREE_TYPE (val
);
7783 const enum tree_code coder
= TREE_CODE (rhstype
);
7784 const enum tree_code codel
= TREE_CODE (type
);
7785 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7787 && check_missing_format_attribute (type
, rhstype
))
7788 warning (OPT_Wsuggest_attribute_format
,
7789 "argument of function call might be a candidate "
7790 "for a format attribute");
7792 maybe_warn_parm_abi (type
, cp_expr_loc_or_input_loc (val
));
7795 if (complain
& tf_warning
)
7796 warn_for_address_or_pointer_of_packed_member (type
, val
);
7801 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7802 which just decay_conversion or no conversions at all should be done.
7803 This is true for some builtins which don't act like normal functions.
7804 Return 2 if no conversions at all should be done, 1 if just
7805 decay_conversion. Return 3 for special treatment of the 3rd argument
7806 for __builtin_*_overflow_p. */
7809 magic_varargs_p (tree fn
)
7811 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7812 switch (DECL_FUNCTION_CODE (fn
))
7814 case BUILT_IN_CLASSIFY_TYPE
:
7815 case BUILT_IN_CONSTANT_P
:
7816 case BUILT_IN_NEXT_ARG
:
7817 case BUILT_IN_VA_START
:
7820 case BUILT_IN_ADD_OVERFLOW_P
:
7821 case BUILT_IN_SUB_OVERFLOW_P
:
7822 case BUILT_IN_MUL_OVERFLOW_P
:
7826 return lookup_attribute ("type generic",
7827 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7833 /* Returns the decl of the dispatcher function if FN is a function version. */
7836 get_function_version_dispatcher (tree fn
)
7838 tree dispatcher_decl
= NULL
;
7840 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7841 && DECL_FUNCTION_VERSIONED (fn
));
7843 gcc_assert (targetm
.get_function_versions_dispatcher
);
7844 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7846 if (dispatcher_decl
== NULL
)
7848 error_at (input_location
, "use of multiversioned function "
7849 "without a default");
7853 retrofit_lang_decl (dispatcher_decl
);
7854 gcc_assert (dispatcher_decl
!= NULL
);
7855 return dispatcher_decl
;
7858 /* fn is a function version dispatcher that is marked used. Mark all the
7859 semantically identical function versions it will dispatch as used. */
7862 mark_versions_used (tree fn
)
7864 struct cgraph_node
*node
;
7865 struct cgraph_function_version_info
*node_v
;
7866 struct cgraph_function_version_info
*it_v
;
7868 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7870 node
= cgraph_node::get (fn
);
7874 gcc_assert (node
->dispatcher_function
);
7876 node_v
= node
->function_version ();
7880 /* All semantically identical versions are chained. Traverse and mark each
7881 one of them as used. */
7882 it_v
= node_v
->next
;
7883 while (it_v
!= NULL
)
7885 mark_used (it_v
->this_node
->decl
);
7890 /* Build a call to "the copy constructor" for the type of A, even if it
7891 wouldn't be selected by normal overload resolution. Used for
7895 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7897 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7898 tree binfo
= TYPE_BINFO (ctype
);
7899 tree copy
= get_copy_ctor (ctype
, complain
);
7900 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7901 tree ob
= build_dummy_object (ctype
);
7902 releasing_vec
args (make_tree_vector_single (a
));
7903 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7904 LOOKUP_NORMAL
, NULL
, complain
);
7908 /* Return true iff T refers to a base field. */
7911 is_base_field_ref (tree t
)
7914 if (TREE_CODE (t
) == ADDR_EXPR
)
7915 t
= TREE_OPERAND (t
, 0);
7916 if (TREE_CODE (t
) == COMPONENT_REF
)
7917 t
= TREE_OPERAND (t
, 1);
7918 if (TREE_CODE (t
) == FIELD_DECL
)
7919 return DECL_FIELD_IS_BASE (t
);
7923 /* We can't elide a copy from a function returning by value to a base
7924 subobject, as the callee might clobber tail padding. Return true iff this
7925 could be that case. */
7928 unsafe_copy_elision_p (tree target
, tree exp
)
7930 /* Copy elision only happens with a TARGET_EXPR. */
7931 if (TREE_CODE (exp
) != TARGET_EXPR
)
7933 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7934 /* It's safe to elide the copy for a class with no tail padding. */
7935 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7937 /* It's safe to elide the copy if we aren't initializing a base object. */
7938 if (!is_base_field_ref (target
))
7940 tree init
= TARGET_EXPR_INITIAL (exp
);
7941 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7942 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7943 init
= TREE_OPERAND (init
, 1);
7944 if (TREE_CODE (init
) == COND_EXPR
)
7946 /* We'll end up copying from each of the arms of the COND_EXPR directly
7947 into the target, so look at them. */
7948 if (tree op
= TREE_OPERAND (init
, 1))
7949 if (unsafe_copy_elision_p (target
, op
))
7951 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7953 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7954 && !AGGR_INIT_VIA_CTOR_P (init
));
7957 /* True iff C is a conversion that binds a reference to a prvalue. */
7960 conv_binds_ref_to_prvalue (conversion
*c
)
7962 if (c
->kind
!= ck_ref_bind
)
7964 if (c
->need_temporary_p
)
7967 c
= next_conversion (c
);
7969 if (c
->kind
== ck_rvalue
)
7971 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7973 if (c
->kind
== ck_identity
&& c
->u
.expr
7974 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7980 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7981 class type or a pointer to class type. */
7984 build_trivial_dtor_call (tree instance
)
7986 gcc_assert (!is_dummy_object (instance
));
7988 if (!flag_lifetime_dse
)
7991 return fold_convert (void_type_node
, instance
);
7994 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
7996 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7998 instance
= cp_build_fold_indirect_ref (instance
);
8001 /* A trivial destructor should still clobber the object. */
8002 tree clobber
= build_clobber (TREE_TYPE (instance
));
8003 return build2 (MODIFY_EXPR
, void_type_node
,
8007 /* Subroutine of the various build_*_call functions. Overload resolution
8008 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
8009 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
8010 bitmask of various LOOKUP_* flags which apply to the call itself. */
8013 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
8016 const vec
<tree
, va_gc
> *args
= cand
->args
;
8017 tree first_arg
= cand
->first_arg
;
8018 conversion
**convs
= cand
->convs
;
8020 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
8025 unsigned int arg_index
= 0;
8029 bool already_used
= false;
8031 /* In a template, there is no need to perform all of the work that
8032 is normally done. We are only interested in the type of the call
8033 expression, i.e., the return type of the function. Any semantic
8034 errors will be deferred until the template is instantiated. */
8035 if (processing_template_decl
)
8039 const tree
*argarray
;
8042 if (undeduced_auto_decl (fn
))
8043 mark_used (fn
, complain
);
8045 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
8049 return_type
= TREE_TYPE (TREE_TYPE (fn
));
8050 nargs
= vec_safe_length (args
);
8051 if (first_arg
== NULL_TREE
)
8052 argarray
= args
->address ();
8060 alcarray
= XALLOCAVEC (tree
, nargs
);
8061 alcarray
[0] = build_this (first_arg
);
8062 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
8063 alcarray
[ix
+ 1] = arg
;
8064 argarray
= alcarray
;
8067 addr
= build_addr_func (fn
, complain
);
8068 if (addr
== error_mark_node
)
8069 return error_mark_node
;
8070 expr
= build_call_array_loc (input_location
, return_type
,
8071 addr
, nargs
, argarray
);
8072 if (TREE_THIS_VOLATILE (fn
) && cfun
)
8073 current_function_returns_abnormally
= 1;
8074 return convert_from_reference (expr
);
8077 /* Give any warnings we noticed during overload resolution. */
8078 if (cand
->warnings
&& (complain
& tf_warning
))
8080 struct candidate_warning
*w
;
8081 for (w
= cand
->warnings
; w
; w
= w
->next
)
8082 joust (cand
, w
->loser
, 1, complain
);
8085 /* Core issue 2327: P0135 doesn't say how to handle the case where the
8086 argument to the copy constructor ends up being a prvalue after
8087 conversion. Let's do the normal processing, but pretend we aren't
8088 actually using the copy constructor. */
8089 bool force_elide
= false;
8090 if (cxx_dialect
>= cxx17
8091 && cand
->num_convs
== 1
8092 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
8093 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8094 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8095 && conv_binds_ref_to_prvalue (convs
[0]))
8098 goto not_really_used
;
8101 /* OK, we're actually calling this inherited constructor; set its deletedness
8102 appropriately. We can get away with doing this here because calling is
8103 the only way to refer to a constructor. */
8104 if (DECL_INHERITED_CTOR (fn
))
8105 deduce_inheriting_ctor (fn
);
8107 /* Make =delete work with SFINAE. */
8108 if (DECL_DELETED_FN (fn
))
8110 if (complain
& tf_error
)
8112 return error_mark_node
;
8115 if (DECL_FUNCTION_MEMBER_P (fn
))
8118 /* If FN is a template function, two cases must be considered.
8123 template <class T> void f();
8125 template <class T> struct B {
8129 struct C : A, B<int> {
8131 using B<int>::g; // #2
8134 In case #1 where `A::f' is a member template, DECL_ACCESS is
8135 recorded in the primary template but not in its specialization.
8136 We check access of FN using its primary template.
8138 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
8139 because it is a member of class template B, DECL_ACCESS is
8140 recorded in the specialization `B<int>::g'. We cannot use its
8141 primary template because `B<T>::g' and `B<int>::g' may have
8142 different access. */
8143 if (DECL_TEMPLATE_INFO (fn
)
8144 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
8145 access_fn
= DECL_TI_TEMPLATE (fn
);
8148 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
8150 return error_mark_node
;
8153 /* If we're checking for implicit delete, don't bother with argument
8155 if (flags
& LOOKUP_SPECULATIVE
)
8157 if (cand
->viable
== 1)
8159 else if (!(complain
& tf_error
))
8160 /* Reject bad conversions now. */
8161 return error_mark_node
;
8162 /* else continue to get conversion error. */
8167 /* N3276 magic doesn't apply to nested calls. */
8168 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8169 complain
&= ~tf_decltype
;
8170 /* No-Cleanup doesn't apply to nested calls either. */
8171 tsubst_flags_t no_cleanup_complain
= complain
;
8172 complain
&= ~tf_no_cleanup
;
8174 /* Find maximum size of vector to hold converted arguments. */
8175 parmlen
= list_length (parm
);
8176 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8177 if (parmlen
> nargs
)
8179 argarray
= XALLOCAVEC (tree
, nargs
);
8181 /* The implicit parameters to a constructor are not considered by overload
8182 resolution, and must be of the proper type. */
8183 if (DECL_CONSTRUCTOR_P (fn
))
8186 if (first_arg
!= NULL_TREE
)
8188 object_arg
= first_arg
;
8189 first_arg
= NULL_TREE
;
8193 object_arg
= (*args
)[arg_index
];
8196 argarray
[j
++] = build_this (object_arg
);
8197 parm
= TREE_CHAIN (parm
);
8198 /* We should never try to call the abstract constructor. */
8199 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8201 if (DECL_HAS_VTT_PARM_P (fn
))
8203 argarray
[j
++] = (*args
)[arg_index
];
8205 parm
= TREE_CHAIN (parm
);
8208 if (flags
& LOOKUP_PREFER_RVALUE
)
8210 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8211 the first parameter of the selected constructor is not an rvalue
8212 reference to the object's type (possibly cv-qualified)...." */
8213 gcc_assert (!(complain
& tf_error
));
8214 tree ptype
= convs
[0]->type
;
8215 if (!TYPE_REF_P (ptype
)
8216 || !TYPE_REF_IS_RVALUE (ptype
)
8217 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8218 return error_mark_node
;
8221 /* Bypass access control for 'this' parameter. */
8222 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8224 tree parmtype
= TREE_VALUE (parm
);
8225 tree arg
= build_this (first_arg
!= NULL_TREE
8227 : (*args
)[arg_index
]);
8228 tree argtype
= TREE_TYPE (arg
);
8232 if (arg
== error_mark_node
)
8233 return error_mark_node
;
8235 if (convs
[i
]->bad_p
)
8237 if (complain
& tf_error
)
8239 auto_diagnostic_group d
;
8240 if (permerror (input_location
, "passing %qT as %<this%> "
8241 "argument discards qualifiers",
8242 TREE_TYPE (argtype
)))
8243 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8246 return error_mark_node
;
8249 /* Optimize away vtable lookup if we know that this
8250 function can't be overridden. We need to check if
8251 the context and the type where we found fn are the same,
8252 actually FN might be defined in a different class
8253 type because of a using-declaration. In this case, we
8254 do not want to perform a non-virtual call. Note that
8255 resolves_to_fixed_type_p checks CLASSTYPE_FINAL too. */
8256 if (DECL_FINAL_P (fn
)
8257 || (resolves_to_fixed_type_p (arg
, 0)
8258 && same_type_ignoring_top_level_qualifiers_p
8259 (DECL_CONTEXT (fn
), BINFO_TYPE (cand
->conversion_path
))))
8260 flags
|= LOOKUP_NONVIRTUAL
;
8262 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8263 X is called for an object that is not of type X, or of a type
8264 derived from X, the behavior is undefined.
8266 So we can assume that anything passed as 'this' is non-null, and
8267 optimize accordingly. */
8268 gcc_assert (TYPE_PTR_P (parmtype
));
8269 /* Convert to the base in which the function was declared. */
8270 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8271 converted_arg
= build_base_path (PLUS_EXPR
,
8273 cand
->conversion_path
,
8275 /* Check that the base class is accessible. */
8276 if (!accessible_base_p (TREE_TYPE (argtype
),
8277 BINFO_TYPE (cand
->conversion_path
), true))
8279 if (complain
& tf_error
)
8280 error ("%qT is not an accessible base of %qT",
8281 BINFO_TYPE (cand
->conversion_path
),
8282 TREE_TYPE (argtype
));
8284 return error_mark_node
;
8286 /* If fn was found by a using declaration, the conversion path
8287 will be to the derived class, not the base declaring fn. We
8288 must convert from derived to base. */
8289 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8290 TREE_TYPE (parmtype
), ba_unique
,
8292 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8293 base_binfo
, 1, complain
);
8295 argarray
[j
++] = converted_arg
;
8296 parm
= TREE_CHAIN (parm
);
8297 if (first_arg
!= NULL_TREE
)
8298 first_arg
= NULL_TREE
;
8305 gcc_assert (first_arg
== NULL_TREE
);
8306 for (; arg_index
< vec_safe_length (args
) && parm
;
8307 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8309 tree type
= TREE_VALUE (parm
);
8310 tree arg
= (*args
)[arg_index
];
8311 bool conversion_warning
= true;
8315 /* If the argument is NULL and used to (implicitly) instantiate a
8316 template function (and bind one of the template arguments to
8317 the type of 'long int'), we don't want to warn about passing NULL
8318 to non-pointer argument.
8319 For example, if we have this template function:
8321 template<typename T> void func(T x) {}
8323 we want to warn (when -Wconversion is enabled) in this case:
8329 but not in this case:
8335 if (null_node_p (arg
)
8336 && DECL_TEMPLATE_INFO (fn
)
8337 && cand
->template_decl
8338 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8339 conversion_warning
= false;
8341 /* Warn about initializer_list deduction that isn't currently in the
8343 if (cxx_dialect
> cxx98
8344 && flag_deduce_init_list
8345 && cand
->template_decl
8346 && is_std_init_list (non_reference (type
))
8347 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
8349 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
8350 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
8351 tree patparm
= get_pattern_parm (realparm
, tmpl
);
8352 tree pattype
= TREE_TYPE (patparm
);
8353 if (PACK_EXPANSION_P (pattype
))
8354 pattype
= PACK_EXPANSION_PATTERN (pattype
);
8355 pattype
= non_reference (pattype
);
8357 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
8358 && (cand
->explicit_targs
== NULL_TREE
8359 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
8360 <= TEMPLATE_TYPE_IDX (pattype
))))
8362 pedwarn (input_location
, 0, "deducing %qT as %qT",
8363 non_reference (TREE_TYPE (patparm
)),
8364 non_reference (type
));
8365 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
8366 " in call to %qD", cand
->fn
);
8367 pedwarn (input_location
, 0,
8368 " (you can disable this with "
8369 "%<-fno-deduce-init-list%>)");
8373 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8374 knows not to allow any more UDCs. This needs to happen after we
8375 process cand->warnings. */
8376 if (flags
& LOOKUP_NO_CONVERSION
)
8377 conv
->user_conv_p
= true;
8379 tsubst_flags_t arg_complain
= complain
;
8380 if (!conversion_warning
)
8381 arg_complain
&= ~tf_warning
;
8383 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8385 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8387 if (val
== error_mark_node
)
8388 return error_mark_node
;
8390 argarray
[j
++] = val
;
8393 /* Default arguments */
8394 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8396 if (TREE_VALUE (parm
) == error_mark_node
)
8397 return error_mark_node
;
8398 val
= convert_default_arg (TREE_VALUE (parm
),
8399 TREE_PURPOSE (parm
),
8402 if (val
== error_mark_node
)
8403 return error_mark_node
;
8404 argarray
[j
++] = val
;
8408 int magic
= magic_varargs_p (fn
);
8409 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8411 tree a
= (*args
)[arg_index
];
8412 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8414 /* Do no conversions for certain magic varargs. */
8415 a
= mark_type_use (a
);
8416 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8417 return error_mark_node
;
8419 else if (magic
!= 0)
8420 /* For other magic varargs only do decay_conversion. */
8421 a
= decay_conversion (a
, complain
);
8422 else if (DECL_CONSTRUCTOR_P (fn
)
8423 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8426 /* Avoid infinite recursion trying to call A(...). */
8427 if (complain
& tf_error
)
8428 /* Try to call the actual copy constructor for a good error. */
8429 call_copy_ctor (a
, complain
);
8430 return error_mark_node
;
8433 a
= convert_arg_to_ellipsis (a
, complain
);
8434 if (a
== error_mark_node
)
8435 return error_mark_node
;
8439 gcc_assert (j
<= nargs
);
8442 /* Avoid to do argument-transformation, if warnings for format, and for
8443 nonnull are disabled. Just in case that at least one of them is active
8444 the check_function_arguments function might warn about something. */
8446 bool warned_p
= false;
8449 || warn_suggest_attribute_format
8452 tree
*fargs
= (!nargs
? argarray
8453 : (tree
*) alloca (nargs
* sizeof (tree
)));
8454 for (j
= 0; j
< nargs
; j
++)
8456 /* For -Wformat undo the implicit passing by hidden reference
8457 done by convert_arg_to_ellipsis. */
8458 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8459 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8460 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8462 fargs
[j
] = argarray
[j
];
8465 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8466 nargs
, fargs
, NULL
);
8469 if (DECL_INHERITED_CTOR (fn
))
8471 /* Check for passing ellipsis arguments to an inherited constructor. We
8472 could handle this by open-coding the inherited constructor rather than
8473 defining it, but let's not bother now. */
8474 if (!cp_unevaluated_operand
8476 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8478 if (complain
& tf_error
)
8480 sorry ("passing arguments to ellipsis of inherited constructor "
8482 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8484 return error_mark_node
;
8487 /* A base constructor inheriting from a virtual base doesn't get the
8488 inherited arguments, just this and __vtt. */
8489 if (ctor_omit_inherited_parms (fn
))
8493 /* Avoid actually calling copy constructors and copy assignment operators,
8496 if (! flag_elide_constructors
&& !force_elide
)
8497 /* Do things the hard way. */;
8498 else if (cand
->num_convs
== 1
8499 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8500 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8501 /* It's unsafe to elide the constructor when handling
8502 a noexcept-expression, it may evaluate to the wrong
8503 value (c++/53025). */
8504 && (force_elide
|| cp_noexcept_operand
== 0))
8507 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8509 bool trivial
= trivial_fn_p (fn
);
8511 /* Pull out the real argument, disregarding const-correctness. */
8513 /* Strip the reference binding for the constructor parameter. */
8514 if (CONVERT_EXPR_P (targ
)
8515 && TYPE_REF_P (TREE_TYPE (targ
)))
8516 targ
= TREE_OPERAND (targ
, 0);
8517 /* But don't strip any other reference bindings; binding a temporary to a
8518 reference prevents copy elision. */
8519 while ((CONVERT_EXPR_P (targ
)
8520 && !TYPE_REF_P (TREE_TYPE (targ
)))
8521 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8522 targ
= TREE_OPERAND (targ
, 0);
8523 if (TREE_CODE (targ
) == ADDR_EXPR
)
8525 targ
= TREE_OPERAND (targ
, 0);
8526 if (!same_type_ignoring_top_level_qualifiers_p
8527 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8536 arg
= cp_build_fold_indirect_ref (arg
);
8538 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8540 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8541 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8543 /* It's from binding the ref parm to a packed field. */
8544 || convs
[0]->need_temporary_p
8546 /* See unsafe_copy_elision_p. */
8547 || DECL_BASE_CONSTRUCTOR_P (fn
));
8550 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8551 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8553 /* [class.copy]: the copy constructor is implicitly defined even if the
8554 implementation elided its use. But don't warn about deprecation when
8555 eliding a temporary, as then no copy is actually performed. */
8556 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8558 /* The language says this isn't called. */;
8561 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8562 return error_mark_node
;
8563 already_used
= true;
8566 cp_warn_deprecated_use (fn
, complain
);
8568 /* If we're creating a temp and we already have one, don't create a
8569 new one. If we're not creating a temp but we get one, use
8570 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8571 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8572 temp or an INIT_EXPR otherwise. */
8573 if (is_dummy_object (fa
))
8575 if (TREE_CODE (arg
) == TARGET_EXPR
)
8578 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8580 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8583 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8585 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8589 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8590 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8591 && trivial_fn_p (fn
))
8593 tree to
= cp_stabilize_reference
8594 (cp_build_fold_indirect_ref (argarray
[0]));
8595 tree type
= TREE_TYPE (to
);
8596 tree as_base
= CLASSTYPE_AS_BASE (type
);
8597 tree arg
= argarray
[1];
8598 location_t loc
= cp_expr_loc_or_input_loc (arg
);
8600 if (is_really_empty_class (type
, /*ignore_vptr*/true))
8602 /* Avoid copying empty classes. */
8603 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8604 TREE_NO_WARNING (val
) = 1;
8606 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8608 if (is_std_init_list (type
)
8609 && conv_binds_ref_to_prvalue (convs
[1]))
8610 warning_at (loc
, OPT_Winit_list_lifetime
,
8611 "assignment from temporary %<initializer_list%> does "
8612 "not extend the lifetime of the underlying array");
8613 arg
= cp_build_fold_indirect_ref (arg
);
8614 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8618 /* We must only copy the non-tail padding parts. */
8620 tree array_type
, alias_set
;
8622 arg2
= TYPE_SIZE_UNIT (as_base
);
8623 arg0
= cp_build_addr_expr (to
, complain
);
8625 array_type
= build_array_type (unsigned_char_type_node
,
8627 (size_binop (MINUS_EXPR
,
8628 arg2
, size_int (1))));
8629 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8630 t
= build2 (MODIFY_EXPR
, void_type_node
,
8631 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8632 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8633 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8634 TREE_NO_WARNING (val
) = 1;
8637 cp_warn_deprecated_use (fn
, complain
);
8641 else if (trivial_fn_p (fn
))
8643 if (DECL_DESTRUCTOR_P (fn
))
8644 return build_trivial_dtor_call (argarray
[0]);
8645 else if (default_ctor_p (fn
))
8647 if (is_dummy_object (argarray
[0]))
8648 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8649 no_cleanup_complain
);
8651 return cp_build_fold_indirect_ref (argarray
[0]);
8655 gcc_assert (!force_elide
);
8658 && !mark_used (fn
, complain
))
8659 return error_mark_node
;
8661 /* Warn if the built-in writes to an object of a non-trivial type. */
8662 if (warn_class_memaccess
8663 && vec_safe_length (args
) >= 2
8664 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8665 maybe_warn_class_memaccess (input_location
, fn
, args
);
8667 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8670 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8672 ba_any
, NULL
, complain
);
8673 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8675 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8677 if (TREE_SIDE_EFFECTS (argarray
[0]))
8678 argarray
[0] = save_expr (argarray
[0]);
8679 t
= build_pointer_type (TREE_TYPE (fn
));
8680 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8685 fn
= build_addr_func (fn
, complain
);
8686 if (fn
== error_mark_node
)
8687 return error_mark_node
;
8690 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8691 if (call
== error_mark_node
)
8693 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8695 tree c
= extract_call_expr (call
);
8696 /* build_new_op_1 will clear this when appropriate. */
8697 CALL_EXPR_ORDERED_ARGS (c
) = true;
8701 tree c
= extract_call_expr (call
);
8702 if (TREE_CODE (c
) == CALL_EXPR
)
8703 TREE_NO_WARNING (c
) = 1;
8711 /* Return the DECL of the first non-static subobject of class TYPE
8712 that satisfies the predicate PRED or null if none can be found. */
8714 template <class Predicate
>
8716 first_non_static_field (tree type
, Predicate pred
)
8718 if (!type
|| !CLASS_TYPE_P (type
))
8721 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8723 if (TREE_CODE (field
) != FIELD_DECL
)
8725 if (TREE_STATIC (field
))
8733 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8734 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8736 tree base
= TREE_TYPE (base_binfo
);
8739 if (tree field
= first_non_static_field (base
, pred
))
8746 struct NonPublicField
8748 bool operator() (const_tree t
)
8750 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8754 /* Return the DECL of the first non-public subobject of class TYPE
8755 or null if none can be found. */
8758 first_non_public_field (tree type
)
8760 return first_non_static_field (type
, NonPublicField ());
8763 struct NonTrivialField
8765 bool operator() (const_tree t
)
8767 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8771 /* Return the DECL of the first non-trivial subobject of class TYPE
8772 or null if none can be found. */
8775 first_non_trivial_field (tree type
)
8777 return first_non_static_field (type
, NonTrivialField ());
8780 } /* unnamed namespace */
8782 /* Return true if all copy and move assignment operator overloads for
8783 class TYPE are trivial and at least one of them is not deleted and,
8784 when ACCESS is set, accessible. Return false otherwise. Set
8785 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8786 copy or move assignment. */
8789 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8791 tree fns
= get_class_binding (type
, assign_op_identifier
);
8792 bool all_trivial
= true;
8794 /* Iterate over overloads of the assignment operator, checking
8795 accessible copy assignments for triviality. */
8797 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8801 /* Skip operators that aren't copy assignments. */
8805 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8806 || accessible_p (TYPE_BINFO (type
), f
, true));
8808 /* Skip template assignment operators and deleted functions. */
8809 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8815 if (!accessible
|| !trivial_fn_p (f
))
8816 all_trivial
= false;
8818 /* Break early when both properties have been determined. */
8819 if (*hasassign
&& !all_trivial
)
8823 /* Return true if they're all trivial and one of the expressions
8824 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8825 tree ref
= cp_build_reference_type (type
, false);
8827 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8828 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8831 /* Return true if all copy and move ctor overloads for class TYPE are
8832 trivial and at least one of them is not deleted and, when ACCESS is
8833 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8834 to true when the TYPE has a (not necessarily trivial) default and copy
8835 (or move) ctor, respectively. */
8838 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8840 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8841 bool all_trivial
= true;
8843 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8847 /* Skip template constructors. */
8848 if (TREE_CODE (f
) != FUNCTION_DECL
)
8851 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8853 /* Skip ctors other than default, copy, and move. */
8854 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8857 if (DECL_DELETED_FN (f
))
8860 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8861 || accessible_p (TYPE_BINFO (type
), f
, true));
8864 hasctor
[cpy_or_move_ctor_p
] = true;
8866 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8867 all_trivial
= false;
8869 /* Break early when both properties have been determined. */
8870 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8877 /* Issue a warning on a call to the built-in function FNDECL if it is
8878 a raw memory write whose destination is not an object of (something
8879 like) trivial or standard layout type with a non-deleted assignment
8880 and copy ctor. Detects const correctness violations, corrupting
8881 references, virtual table pointers, and bypassing non-trivial
8885 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8886 const vec
<tree
, va_gc
> *args
)
8888 /* Except for bcopy where it's second, the destination pointer is
8889 the first argument for all functions handled here. Compute
8890 the index of the destination and source arguments. */
8891 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8892 unsigned srcidx
= !dstidx
;
8894 tree dest
= (*args
)[dstidx
];
8895 if (!TREE_TYPE (dest
) || !INDIRECT_TYPE_P (TREE_TYPE (dest
)))
8898 tree srctype
= NULL_TREE
;
8900 /* Determine the type of the pointed-to object and whether it's
8901 a complete class type. */
8902 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8904 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8907 /* Check to see if the raw memory call is made by a non-static member
8908 function with THIS as the destination argument for the destination
8909 type. If so, and if the class has no non-trivial bases or members,
8910 be more permissive. */
8911 if (current_function_decl
8912 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8913 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8915 tree ctx
= DECL_CONTEXT (current_function_decl
);
8916 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8917 tree binfo
= TYPE_BINFO (ctx
);
8920 && !BINFO_VTABLE (binfo
)
8921 && !first_non_trivial_field (desttype
))
8925 /* True if the class is trivial. */
8926 bool trivial
= trivial_type_p (desttype
);
8928 /* Set to true if DESTYPE has an accessible copy assignment. */
8929 bool hasassign
= false;
8930 /* True if all of the class' overloaded copy assignment operators
8931 are all trivial (and not deleted) and at least one of them is
8933 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8935 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8937 bool hasctors
[2] = { false, false };
8939 /* True if all of the class' overloaded copy constructors are all
8940 trivial (and not deleted) and at least one of them is accessible. */
8941 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8943 /* Set FLD to the first private/protected member of the class. */
8944 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8946 /* The warning format string. */
8947 const char *warnfmt
= NULL
;
8948 /* A suggested alternative to offer instead of the raw memory call.
8949 Empty string when none can be come up with. */
8950 const char *suggest
= "";
8951 bool warned
= false;
8953 switch (DECL_FUNCTION_CODE (fndecl
))
8955 case BUILT_IN_MEMSET
:
8956 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8958 /* Diagnose setting non-copy-assignable or non-trivial types,
8959 or types with a private member, to (potentially) non-zero
8960 bytes. Since the value of the bytes being written is unknown,
8961 suggest using assignment instead (if one exists). Also warn
8962 for writes into objects for which zero-initialization doesn't
8963 mean all bits clear (pointer-to-member data, where null is all
8964 bits set). Since the value being written is (most likely)
8965 non-zero, simply suggest assignment (but not copy assignment). */
8966 suggest
= "; use assignment instead";
8968 warnfmt
= G_("%qD writing to an object of type %#qT with "
8969 "no trivial copy-assignment");
8971 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8974 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8975 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8976 "%qD writing to an object of type %#qT with "
8978 fndecl
, desttype
, access
, fld
);
8980 else if (!zero_init_p (desttype
))
8981 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8982 "a pointer to data member%s");
8988 case BUILT_IN_BZERO
:
8989 /* Similarly to the above, diagnose clearing non-trivial or non-
8990 standard layout objects, or objects of types with no assignmenmt.
8991 Since the value being written is known to be zero, suggest either
8992 copy assignment, copy ctor, or default ctor as an alternative,
8993 depending on what's available. */
8995 if (hasassign
&& hasctors
[0])
8996 suggest
= G_("; use assignment or value-initialization instead");
8998 suggest
= G_("; use assignment instead");
8999 else if (hasctors
[0])
9000 suggest
= G_("; use value-initialization instead");
9003 warnfmt
= G_("%qD clearing an object of type %#qT with "
9004 "no trivial copy-assignment%s");
9006 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
9007 else if (!zero_init_p (desttype
))
9008 warnfmt
= G_("%qD clearing an object of type %#qT containing "
9009 "a pointer-to-member%s");
9012 case BUILT_IN_BCOPY
:
9013 case BUILT_IN_MEMCPY
:
9014 case BUILT_IN_MEMMOVE
:
9015 case BUILT_IN_MEMPCPY
:
9016 /* Determine the type of the source object. */
9017 srctype
= TREE_TYPE ((*args
)[srcidx
]);
9018 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
9019 srctype
= void_type_node
;
9021 srctype
= TREE_TYPE (srctype
);
9023 /* Since it's impossible to determine wheter the byte copy is
9024 being used in place of assignment to an existing object or
9025 as a substitute for initialization, assume it's the former.
9026 Determine the best alternative to use instead depending on
9027 what's not deleted. */
9028 if (hasassign
&& hasctors
[1])
9029 suggest
= G_("; use copy-assignment or copy-initialization instead");
9031 suggest
= G_("; use copy-assignment instead");
9032 else if (hasctors
[1])
9033 suggest
= G_("; use copy-initialization instead");
9036 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
9037 "copy-assignment%s");
9038 else if (!trivially_copyable_p (desttype
))
9039 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
9042 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
9045 && !VOID_TYPE_P (srctype
)
9046 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9047 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9050 /* Warn when copying into a non-trivial object from an object
9051 of a different type other than void or char. */
9052 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9053 "%qD copying an object of non-trivial type "
9054 "%#qT from an array of %#qT",
9055 fndecl
, desttype
, srctype
);
9058 && !VOID_TYPE_P (srctype
)
9059 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9060 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9063 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
9064 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9065 "%qD copying an object of type %#qT with "
9066 "%qs member %qD from an array of %#qT; use "
9067 "assignment or copy-initialization instead",
9068 fndecl
, desttype
, access
, fld
, srctype
);
9070 else if (!trivial
&& vec_safe_length (args
) > 2)
9072 tree sz
= maybe_constant_value ((*args
)[2]);
9073 if (!tree_fits_uhwi_p (sz
))
9076 /* Finally, warn on partial copies. */
9077 unsigned HOST_WIDE_INT typesize
9078 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
9079 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
9080 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9081 (typesize
- partial
> 1
9082 ? G_("%qD writing to an object of "
9083 "a non-trivial type %#qT leaves %wu "
9085 : G_("%qD writing to an object of "
9086 "a non-trivial type %#qT leaves %wu "
9088 fndecl
, desttype
, typesize
- partial
);
9092 case BUILT_IN_REALLOC
:
9094 if (!trivially_copyable_p (desttype
))
9095 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
9096 "%#qT; use %<new%> and %<delete%> instead");
9098 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
9099 "constructor; use %<new%> and %<delete%> instead");
9100 else if (!get_dtor (desttype
, tf_none
))
9101 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
9105 tree sz
= maybe_constant_value ((*args
)[1]);
9106 if (TREE_CODE (sz
) == INTEGER_CST
9107 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
9108 /* Finally, warn on reallocation into insufficient space. */
9109 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9110 "%qD moving an object of non-trivial type "
9111 "%#qT and size %E into a region of size %E",
9112 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
9124 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9125 warnfmt
, fndecl
, desttype
, suggest
);
9127 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9128 warnfmt
, fndecl
, desttype
);
9132 inform (location_of (desttype
), "%#qT declared here", desttype
);
9135 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
9136 This function performs no overload resolution, conversion, or other
9137 high-level operations. */
9140 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
9141 tsubst_flags_t complain
)
9145 /* Remember roughly where this call is. */
9146 location_t loc
= cp_expr_loc_or_input_loc (fn
);
9147 fn
= build_call_a (fn
, nargs
, argarray
);
9148 SET_EXPR_LOCATION (fn
, loc
);
9150 fndecl
= get_callee_fndecl (fn
);
9152 /* Check that arguments to builtin functions match the expectations. */
9154 && !processing_template_decl
9155 && fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
9159 /* We need to take care that values to BUILT_IN_NORMAL
9161 for (i
= 0; i
< nargs
; i
++)
9162 argarray
[i
] = maybe_constant_value (argarray
[i
]);
9164 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
9166 return error_mark_node
;
9169 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9172 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9173 function call is either the operand of a decltype-specifier or the
9174 right operand of a comma operator that is the operand of a
9175 decltype-specifier, a temporary object is not introduced for the
9176 prvalue. The type of the prvalue may be incomplete. */
9177 if (!(complain
& tf_decltype
))
9179 fn
= require_complete_type_sfinae (fn
, complain
);
9180 if (fn
== error_mark_node
)
9181 return error_mark_node
;
9183 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9185 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9186 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9189 return convert_from_reference (fn
);
9192 /* Returns the value to use for the in-charge parameter when making a
9193 call to a function with the indicated NAME.
9195 FIXME:Can't we find a neater way to do this mapping? */
9198 in_charge_arg_for_name (tree name
)
9200 if (IDENTIFIER_CTOR_P (name
))
9202 if (name
== complete_ctor_identifier
)
9203 return integer_one_node
;
9204 gcc_checking_assert (name
== base_ctor_identifier
);
9208 if (name
== complete_dtor_identifier
)
9209 return integer_two_node
;
9210 else if (name
== deleting_dtor_identifier
)
9211 return integer_three_node
;
9212 gcc_checking_assert (name
== base_dtor_identifier
);
9215 return integer_zero_node
;
9218 /* We've built up a constructor call RET. Complain if it delegates to the
9219 constructor we're currently compiling. */
9222 check_self_delegation (tree ret
)
9224 if (TREE_CODE (ret
) == TARGET_EXPR
)
9225 ret
= TARGET_EXPR_INITIAL (ret
);
9226 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9227 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9228 error ("constructor delegates to itself");
9231 /* Build a call to a constructor, destructor, or an assignment
9232 operator for INSTANCE, an expression with class type. NAME
9233 indicates the special member function to call; *ARGS are the
9234 arguments. ARGS may be NULL. This may change ARGS. BINFO
9235 indicates the base of INSTANCE that is to be passed as the `this'
9236 parameter to the member function called.
9238 FLAGS are the LOOKUP_* flags to use when processing the call.
9240 If NAME indicates a complete object constructor, INSTANCE may be
9241 NULL_TREE. In this case, the caller will call build_cplus_new to
9242 store the newly constructed object into a VAR_DECL. */
9245 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9246 tree binfo
, int flags
, tsubst_flags_t complain
)
9249 /* The type of the subobject to be constructed or destroyed. */
9251 vec
<tree
, va_gc
> *allocated
= NULL
;
9254 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9256 if (error_operand_p (instance
))
9257 return error_mark_node
;
9259 if (IDENTIFIER_DTOR_P (name
))
9261 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9262 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9263 /* Shortcut to avoid lazy destructor declaration. */
9264 return build_trivial_dtor_call (instance
);
9269 /* Resolve the name. */
9270 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9271 return error_mark_node
;
9273 binfo
= TYPE_BINFO (binfo
);
9276 gcc_assert (binfo
!= NULL_TREE
);
9278 class_type
= BINFO_TYPE (binfo
);
9280 /* Handle the special case where INSTANCE is NULL_TREE. */
9281 if (name
== complete_ctor_identifier
&& !instance
)
9282 instance
= build_dummy_object (class_type
);
9285 /* Convert to the base class, if necessary. */
9286 if (!same_type_ignoring_top_level_qualifiers_p
9287 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9289 if (IDENTIFIER_CDTOR_P (name
))
9290 /* For constructors and destructors, either the base is
9291 non-virtual, or it is virtual but we are doing the
9292 conversion from a constructor or destructor for the
9293 complete object. In either case, we can convert
9295 instance
= convert_to_base_statically (instance
, binfo
);
9298 /* However, for assignment operators, we must convert
9299 dynamically if the base is virtual. */
9300 gcc_checking_assert (name
== assign_op_identifier
);
9301 instance
= build_base_path (PLUS_EXPR
, instance
,
9302 binfo
, /*nonnull=*/1, complain
);
9307 gcc_assert (instance
!= NULL_TREE
);
9309 /* In C++17, "If the initializer expression is a prvalue and the
9310 cv-unqualified version of the source type is the same class as the class
9311 of the destination, the initializer expression is used to initialize the
9312 destination object." Handle that here to avoid doing overload
9314 if (cxx_dialect
>= cxx17
9315 && args
&& vec_safe_length (*args
) == 1
9316 && name
== complete_ctor_identifier
)
9318 tree arg
= (**args
)[0];
9320 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9321 && !TYPE_HAS_LIST_CTOR (class_type
)
9322 && CONSTRUCTOR_NELTS (arg
) == 1)
9323 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9325 if ((TREE_CODE (arg
) == TARGET_EXPR
9326 || TREE_CODE (arg
) == CONSTRUCTOR
)
9327 && (same_type_ignoring_top_level_qualifiers_p
9328 (class_type
, TREE_TYPE (arg
))))
9330 if (is_dummy_object (instance
))
9332 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9333 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9335 if ((complain
& tf_error
)
9336 && (flags
& LOOKUP_DELEGATING_CONS
))
9337 check_self_delegation (arg
);
9338 /* Avoid change of behavior on Wunused-var-2.C. */
9339 instance
= mark_lvalue_use (instance
);
9340 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9344 fns
= lookup_fnfields (binfo
, name
, 1);
9346 /* When making a call to a constructor or destructor for a subobject
9347 that uses virtual base classes, pass down a pointer to a VTT for
9349 if ((name
== base_ctor_identifier
9350 || name
== base_dtor_identifier
)
9351 && CLASSTYPE_VBASECLASSES (class_type
))
9356 /* If the current function is a complete object constructor
9357 or destructor, then we fetch the VTT directly.
9358 Otherwise, we look it up using the VTT we were given. */
9359 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9360 vtt
= decay_conversion (vtt
, complain
);
9361 if (vtt
== error_mark_node
)
9362 return error_mark_node
;
9363 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9364 if (BINFO_SUBVTT_INDEX (binfo
))
9365 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9371 allocated
= make_tree_vector ();
9375 vec_safe_insert (*args
, 0, sub_vtt
);
9378 ret
= build_new_method_call (instance
, fns
, args
,
9379 TYPE_BINFO (BINFO_TYPE (binfo
)),
9383 if (allocated
!= NULL
)
9384 release_tree_vector (allocated
);
9386 if ((complain
& tf_error
)
9387 && (flags
& LOOKUP_DELEGATING_CONS
)
9388 && name
== complete_ctor_identifier
)
9389 check_self_delegation (ret
);
9394 /* Return the NAME, as a C string. The NAME indicates a function that
9395 is a member of TYPE. *FREE_P is set to true if the caller must
9396 free the memory returned.
9398 Rather than go through all of this, we should simply set the names
9399 of constructors and destructors appropriately, and dispense with
9400 ctor_identifier, dtor_identifier, etc. */
9403 name_as_c_string (tree name
, tree type
, bool *free_p
)
9405 const char *pretty_name
;
9407 /* Assume that we will not allocate memory. */
9409 /* Constructors and destructors are special. */
9410 if (IDENTIFIER_CDTOR_P (name
))
9413 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9414 /* For a destructor, add the '~'. */
9415 if (IDENTIFIER_DTOR_P (name
))
9417 pretty_name
= concat ("~", pretty_name
, NULL
);
9418 /* Remember that we need to free the memory allocated. */
9422 else if (IDENTIFIER_CONV_OP_P (name
))
9424 pretty_name
= concat ("operator ",
9425 type_as_string_translate (TREE_TYPE (name
),
9426 TFF_PLAIN_IDENTIFIER
),
9428 /* Remember that we need to free the memory allocated. */
9432 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9434 return CONST_CAST (char *, pretty_name
);
9437 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9440 static z_candidate
*
9441 single_z_candidate (z_candidate
*candidates
)
9443 if (candidates
== NULL
)
9446 if (candidates
->next
)
9452 /* If CANDIDATE is invalid due to a bad argument type, return the
9453 pertinent conversion_info.
9455 Otherwise, return NULL. */
9457 static const conversion_info
*
9458 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9460 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9461 rejection_reason
*r
= candidate
->reason
;
9471 case rr_arg_conversion
:
9472 return &r
->u
.conversion
;
9474 case rr_bad_arg_conversion
:
9475 return &r
->u
.bad_conversion
;
9479 /* Issue an error and note complaining about a bad argument type at a
9480 callsite with a single candidate FNDECL.
9482 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9483 case input_location is used).
9484 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9485 the formal parameter. */
9488 complain_about_bad_argument (location_t arg_loc
,
9489 tree from_type
, tree to_type
,
9490 tree fndecl
, int parmnum
)
9492 auto_diagnostic_group d
;
9493 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9494 range_label
*label
= &rhs_label
;
9495 if (arg_loc
== UNKNOWN_LOCATION
)
9497 arg_loc
= input_location
;
9500 gcc_rich_location
richloc (arg_loc
, label
);
9502 "cannot convert %qH to %qI",
9503 from_type
, to_type
);
9504 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9508 /* Subroutine of build_new_method_call_1, for where there are no viable
9509 candidates for the call. */
9512 complain_about_no_candidates_for_method_call (tree instance
,
9513 z_candidate
*candidates
,
9514 tree explicit_targs
,
9516 tree optype
, tree name
,
9517 bool skip_first_for_error
,
9518 vec
<tree
, va_gc
> *user_args
)
9520 auto_diagnostic_group d
;
9521 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9522 cxx_incomplete_type_error (instance
, basetype
);
9524 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9525 basetype
, optype
, build_tree_list_vec (user_args
),
9526 TREE_TYPE (instance
));
9529 /* Special-case for when there's a single candidate that's failing
9530 due to a bad argument type. */
9531 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9532 if (const conversion_info
*conv
9533 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9535 complain_about_bad_argument (conv
->loc
,
9536 conv
->from
, conv
->to_type
,
9537 candidate
->fn
, conv
->n_arg
);
9541 tree arglist
= build_tree_list_vec (user_args
);
9542 tree errname
= name
;
9543 bool twiddle
= false;
9544 if (IDENTIFIER_CDTOR_P (errname
))
9546 twiddle
= IDENTIFIER_DTOR_P (errname
);
9547 errname
= constructor_name (basetype
);
9550 errname
= lookup_template_function (errname
, explicit_targs
);
9551 if (skip_first_for_error
)
9552 arglist
= TREE_CHAIN (arglist
);
9553 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9554 basetype
, &"~"[!twiddle
], errname
, arglist
,
9555 TREE_TYPE (instance
));
9557 print_z_candidates (location_of (name
), candidates
);
9560 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9561 be set, upon return, to the function called. ARGS may be NULL.
9562 This may change ARGS. */
9565 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9566 tree conversion_path
, int flags
,
9567 tree
*fn_p
, tsubst_flags_t complain
)
9569 struct z_candidate
*candidates
= 0, *cand
;
9570 tree explicit_targs
= NULL_TREE
;
9571 tree basetype
= NULL_TREE
;
9574 tree first_mem_arg
= NULL_TREE
;
9576 bool skip_first_for_error
;
9577 vec
<tree
, va_gc
> *user_args
;
9580 int template_only
= 0;
9584 vec
<tree
, va_gc
> *orig_args
= NULL
;
9587 gcc_assert (instance
!= NULL_TREE
);
9589 /* We don't know what function we're going to call, yet. */
9593 if (error_operand_p (instance
)
9594 || !fns
|| error_operand_p (fns
))
9595 return error_mark_node
;
9597 if (!BASELINK_P (fns
))
9599 if (complain
& tf_error
)
9600 error ("call to non-function %qD", fns
);
9601 return error_mark_node
;
9604 orig_instance
= instance
;
9607 /* Dismantle the baselink to collect all the information we need. */
9608 if (!conversion_path
)
9609 conversion_path
= BASELINK_BINFO (fns
);
9610 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9611 optype
= BASELINK_OPTYPE (fns
);
9612 fns
= BASELINK_FUNCTIONS (fns
);
9613 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9615 explicit_targs
= TREE_OPERAND (fns
, 1);
9616 fns
= TREE_OPERAND (fns
, 0);
9619 gcc_assert (OVL_P (fns
));
9620 fn
= OVL_FIRST (fns
);
9621 name
= DECL_NAME (fn
);
9623 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9624 gcc_assert (CLASS_TYPE_P (basetype
));
9626 user_args
= args
== NULL
? NULL
: *args
;
9627 /* Under DR 147 A::A() is an invalid constructor call,
9628 not a functional cast. */
9629 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9631 if (! (complain
& tf_error
))
9632 return error_mark_node
;
9634 basetype
= DECL_CONTEXT (fn
);
9635 name
= constructor_name (basetype
);
9636 auto_diagnostic_group d
;
9637 if (permerror (input_location
,
9638 "cannot call constructor %<%T::%D%> directly",
9640 inform (input_location
, "for a function-style cast, remove the "
9641 "redundant %<::%D%>", name
);
9642 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9647 if (processing_template_decl
)
9649 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9650 instance
= build_non_dependent_expr (instance
);
9652 make_args_non_dependent (*args
);
9655 /* Process the argument list. */
9656 if (args
!= NULL
&& *args
!= NULL
)
9658 *args
= resolve_args (*args
, complain
);
9660 return error_mark_node
;
9664 /* Consider the object argument to be used even if we end up selecting a
9665 static member function. */
9666 instance
= mark_type_use (instance
);
9668 /* Figure out whether to skip the first argument for the error
9669 message we will display to users if an error occurs. We don't
9670 want to display any compiler-generated arguments. The "this"
9671 pointer hasn't been added yet. However, we must remove the VTT
9672 pointer if this is a call to a base-class constructor or
9674 skip_first_for_error
= false;
9675 if (IDENTIFIER_CDTOR_P (name
))
9677 /* Callers should explicitly indicate whether they want to ctor
9678 the complete object or just the part without virtual bases. */
9679 gcc_assert (name
!= ctor_identifier
);
9681 /* Remove the VTT pointer, if present. */
9682 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9683 && CLASSTYPE_VBASECLASSES (basetype
))
9684 skip_first_for_error
= true;
9686 /* It's OK to call destructors and constructors on cv-qualified
9687 objects. Therefore, convert the INSTANCE to the unqualified
9688 type, if necessary. */
9689 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9691 instance
= build_this (instance
);
9692 instance
= build_nop (build_pointer_type (basetype
), instance
);
9693 instance
= build_fold_indirect_ref (instance
);
9697 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9699 /* For the overload resolution we need to find the actual `this`
9700 that would be captured if the call turns out to be to a
9701 non-static member function. Do not actually capture it at this
9703 if (DECL_CONSTRUCTOR_P (fn
))
9704 /* Constructors don't use the enclosing 'this'. */
9705 first_mem_arg
= instance
;
9707 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9709 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9710 p
= conversion_obstack_alloc (0);
9712 /* The number of arguments artificial parms in ARGS; we subtract one because
9713 there's no 'this' in ARGS. */
9714 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9716 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9717 initializer, not T({ }). */
9718 if (DECL_CONSTRUCTOR_P (fn
)
9719 && vec_safe_length (user_args
) > skip
9720 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9722 tree init_list
= (*user_args
)[skip
];
9723 tree init
= NULL_TREE
;
9725 gcc_assert (user_args
->length () == skip
+ 1
9726 && !(flags
& LOOKUP_ONLYCONVERTING
));
9728 /* If the initializer list has no elements and T is a class type with
9729 a default constructor, the object is value-initialized. Handle
9730 this here so we don't need to handle it wherever we use
9731 build_special_member_call. */
9732 if (CONSTRUCTOR_NELTS (init_list
) == 0
9733 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9734 /* For a user-provided default constructor, use the normal
9735 mechanisms so that protected access works. */
9736 && type_has_non_user_provided_default_constructor (basetype
)
9737 && !processing_template_decl
)
9738 init
= build_value_init (basetype
, complain
);
9740 /* If BASETYPE is an aggregate, we need to do aggregate
9742 else if (CP_AGGREGATE_TYPE_P (basetype
))
9744 init
= reshape_init (basetype
, init_list
, complain
);
9745 init
= digest_init (basetype
, init
, complain
);
9750 if (is_dummy_object (instance
))
9751 return get_target_expr_sfinae (init
, complain
);
9752 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9753 TREE_SIDE_EFFECTS (init
) = true;
9757 /* Otherwise go ahead with overload resolution. */
9758 add_list_candidates (fns
, first_mem_arg
, user_args
,
9759 basetype
, explicit_targs
, template_only
,
9760 conversion_path
, access_binfo
, flags
,
9761 &candidates
, complain
);
9764 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9765 explicit_targs
, template_only
, conversion_path
,
9766 access_binfo
, flags
, &candidates
, complain
);
9768 any_viable_p
= false;
9769 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9773 if (complain
& tf_error
)
9774 complain_about_no_candidates_for_method_call (instance
, candidates
,
9775 explicit_targs
, basetype
,
9777 skip_first_for_error
,
9779 call
= error_mark_node
;
9783 cand
= tourney (candidates
, complain
);
9790 if (complain
& tf_error
)
9792 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9793 arglist
= build_tree_list_vec (user_args
);
9794 if (skip_first_for_error
)
9795 arglist
= TREE_CHAIN (arglist
);
9796 auto_diagnostic_group d
;
9797 if (!any_strictly_viable (candidates
))
9798 error ("no matching function for call to %<%s(%A)%>",
9799 pretty_name
, arglist
);
9801 error ("call of overloaded %<%s(%A)%> is ambiguous",
9802 pretty_name
, arglist
);
9803 print_z_candidates (location_of (name
), candidates
);
9807 call
= error_mark_node
;
9814 if (!(flags
& LOOKUP_NONVIRTUAL
)
9815 && DECL_PURE_VIRTUAL_P (fn
)
9816 && instance
== current_class_ref
9817 && (complain
& tf_warning
))
9819 /* This is not an error, it is runtime undefined
9821 if (!current_function_decl
)
9822 warning (0, "pure virtual %q#D called from "
9823 "non-static data member initializer", fn
);
9824 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9825 || DECL_DESTRUCTOR_P (current_function_decl
))
9826 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9827 ? G_("pure virtual %q#D called from constructor")
9828 : G_("pure virtual %q#D called from destructor")),
9832 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9833 && !DECL_CONSTRUCTOR_P (fn
)
9834 && is_dummy_object (instance
))
9836 instance
= maybe_resolve_dummy (instance
, true);
9837 if (instance
== error_mark_node
)
9838 call
= error_mark_node
;
9839 else if (!is_dummy_object (instance
))
9841 /* We captured 'this' in the current lambda now that
9842 we know we really need it. */
9843 cand
->first_arg
= instance
;
9845 else if (any_dependent_bases_p ())
9846 /* We can't tell until instantiation time whether we can use
9847 *this as the implicit object argument. */;
9850 if (complain
& tf_error
)
9851 error ("cannot call member function %qD without object",
9853 call
= error_mark_node
;
9857 if (call
!= error_mark_node
)
9860 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9861 /* Now we know what function is being called. */
9864 /* Build the actual CALL_EXPR. */
9865 call
= build_over_call (cand
, flags
, complain
);
9866 /* In an expression of the form `a->f()' where `f' turns
9867 out to be a static member function, `a' is
9868 none-the-less evaluated. */
9869 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9870 && !is_dummy_object (instance
)
9871 && TREE_SIDE_EFFECTS (instance
))
9873 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9876 if (TREE_THIS_VOLATILE (a
))
9878 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9880 else if (call
!= error_mark_node
9881 && DECL_DESTRUCTOR_P (cand
->fn
)
9882 && !VOID_TYPE_P (TREE_TYPE (call
)))
9883 /* An explicit call of the form "x->~X()" has type
9884 "void". However, on platforms where destructors
9885 return "this" (i.e., those where
9886 targetm.cxx.cdtor_returns_this is true), such calls
9887 will appear to have a return value of pointer type
9888 to the low-level call machinery. We do not want to
9889 change the low-level machinery, since we want to be
9890 able to optimize "delete f()" on such platforms as
9891 "operator delete(~X(f()))" (rather than generating
9892 "t = f(), ~X(t), operator delete (t)"). */
9893 call
= build_nop (void_type_node
, call
);
9898 if (processing_template_decl
&& call
!= error_mark_node
)
9900 bool cast_to_void
= false;
9902 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9903 call
= TREE_OPERAND (call
, 1);
9904 else if (TREE_CODE (call
) == NOP_EXPR
)
9906 cast_to_void
= true;
9907 call
= TREE_OPERAND (call
, 0);
9909 if (INDIRECT_REF_P (call
))
9910 call
= TREE_OPERAND (call
, 0);
9911 call
= (build_min_non_dep_call_vec
9913 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9914 orig_instance
, orig_fns
, NULL_TREE
),
9916 SET_EXPR_LOCATION (call
, input_location
);
9917 call
= convert_from_reference (call
);
9919 call
= build_nop (void_type_node
, call
);
9922 /* Free all the conversions we allocated. */
9923 obstack_free (&conversion_obstack
, p
);
9925 if (orig_args
!= NULL
)
9926 release_tree_vector (orig_args
);
9931 /* Wrapper for above. */
9934 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9935 tree conversion_path
, int flags
,
9936 tree
*fn_p
, tsubst_flags_t complain
)
9939 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9940 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9942 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9946 /* Returns true iff standard conversion sequence ICS1 is a proper
9947 subsequence of ICS2. */
9950 is_subseq (conversion
*ics1
, conversion
*ics2
)
9952 /* We can assume that a conversion of the same code
9953 between the same types indicates a subsequence since we only get
9954 here if the types we are converting from are the same. */
9956 while (ics1
->kind
== ck_rvalue
9957 || ics1
->kind
== ck_lvalue
)
9958 ics1
= next_conversion (ics1
);
9962 while (ics2
->kind
== ck_rvalue
9963 || ics2
->kind
== ck_lvalue
)
9964 ics2
= next_conversion (ics2
);
9966 if (ics2
->kind
== ck_user
9967 || ics2
->kind
== ck_ambig
9968 || ics2
->kind
== ck_aggr
9969 || ics2
->kind
== ck_list
9970 || ics2
->kind
== ck_identity
)
9971 /* At this point, ICS1 cannot be a proper subsequence of
9972 ICS2. We can get a USER_CONV when we are comparing the
9973 second standard conversion sequence of two user conversion
9977 ics2
= next_conversion (ics2
);
9979 while (ics2
->kind
== ck_rvalue
9980 || ics2
->kind
== ck_lvalue
)
9981 ics2
= next_conversion (ics2
);
9983 if (ics2
->kind
== ics1
->kind
9984 && same_type_p (ics2
->type
, ics1
->type
)
9985 && (ics1
->kind
== ck_identity
9986 || same_type_p (next_conversion (ics2
)->type
,
9987 next_conversion (ics1
)->type
)))
9992 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9993 be any _TYPE nodes. */
9996 is_properly_derived_from (tree derived
, tree base
)
9998 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
10001 /* We only allow proper derivation here. The DERIVED_FROM_P macro
10002 considers every class derived from itself. */
10003 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
10004 && DERIVED_FROM_P (base
, derived
));
10007 /* We build the ICS for an implicit object parameter as a pointer
10008 conversion sequence. However, such a sequence should be compared
10009 as if it were a reference conversion sequence. If ICS is the
10010 implicit conversion sequence for an implicit object parameter,
10011 modify it accordingly. */
10014 maybe_handle_implicit_object (conversion
**ics
)
10016 if ((*ics
)->this_p
)
10018 /* [over.match.funcs]
10020 For non-static member functions, the type of the
10021 implicit object parameter is "reference to cv X"
10022 where X is the class of which the function is a
10023 member and cv is the cv-qualification on the member
10024 function declaration. */
10025 conversion
*t
= *ics
;
10026 tree reference_type
;
10028 /* The `this' parameter is a pointer to a class type. Make the
10029 implicit conversion talk about a reference to that same class
10031 reference_type
= TREE_TYPE (t
->type
);
10032 reference_type
= build_reference_type (reference_type
);
10034 if (t
->kind
== ck_qual
)
10035 t
= next_conversion (t
);
10036 if (t
->kind
== ck_ptr
)
10037 t
= next_conversion (t
);
10038 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
10039 t
= direct_reference_binding (reference_type
, t
);
10041 t
->rvaluedness_matches_p
= 0;
10046 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
10047 and return the initial reference binding conversion. Otherwise,
10048 leave *ICS unchanged and return NULL. */
10050 static conversion
*
10051 maybe_handle_ref_bind (conversion
**ics
)
10053 if ((*ics
)->kind
== ck_ref_bind
)
10055 conversion
*old_ics
= *ics
;
10056 *ics
= next_conversion (old_ics
);
10057 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
10064 /* Compare two implicit conversion sequences according to the rules set out in
10065 [over.ics.rank]. Return values:
10067 1: ics1 is better than ics2
10068 -1: ics2 is better than ics1
10069 0: ics1 and ics2 are indistinguishable */
10072 compare_ics (conversion
*ics1
, conversion
*ics2
)
10078 tree deref_from_type1
= NULL_TREE
;
10079 tree deref_from_type2
= NULL_TREE
;
10080 tree deref_to_type1
= NULL_TREE
;
10081 tree deref_to_type2
= NULL_TREE
;
10082 conversion_rank rank1
, rank2
;
10084 /* REF_BINDING is nonzero if the result of the conversion sequence
10085 is a reference type. In that case REF_CONV is the reference
10086 binding conversion. */
10087 conversion
*ref_conv1
;
10088 conversion
*ref_conv2
;
10090 /* Compare badness before stripping the reference conversion. */
10091 if (ics1
->bad_p
> ics2
->bad_p
)
10093 else if (ics1
->bad_p
< ics2
->bad_p
)
10096 /* Handle implicit object parameters. */
10097 maybe_handle_implicit_object (&ics1
);
10098 maybe_handle_implicit_object (&ics2
);
10100 /* Handle reference parameters. */
10101 ref_conv1
= maybe_handle_ref_bind (&ics1
);
10102 ref_conv2
= maybe_handle_ref_bind (&ics2
);
10104 /* List-initialization sequence L1 is a better conversion sequence than
10105 list-initialization sequence L2 if L1 converts to
10106 std::initializer_list<X> for some X and L2 does not. */
10107 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
10109 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
10114 When comparing the basic forms of implicit conversion sequences (as
10115 defined in _over.best.ics_)
10117 --a standard conversion sequence (_over.ics.scs_) is a better
10118 conversion sequence than a user-defined conversion sequence
10119 or an ellipsis conversion sequence, and
10121 --a user-defined conversion sequence (_over.ics.user_) is a
10122 better conversion sequence than an ellipsis conversion sequence
10123 (_over.ics.ellipsis_). */
10124 /* Use BAD_CONVERSION_RANK because we already checked for a badness
10125 mismatch. If both ICS are bad, we try to make a decision based on
10126 what would have happened if they'd been good. This is not an
10127 extension, we'll still give an error when we build up the call; this
10128 just helps us give a more helpful error message. */
10129 rank1
= BAD_CONVERSION_RANK (ics1
);
10130 rank2
= BAD_CONVERSION_RANK (ics2
);
10134 else if (rank1
< rank2
)
10137 if (ics1
->ellipsis_p
)
10138 /* Both conversions are ellipsis conversions. */
10141 /* User-defined conversion sequence U1 is a better conversion sequence
10142 than another user-defined conversion sequence U2 if they contain the
10143 same user-defined conversion operator or constructor and if the sec-
10144 ond standard conversion sequence of U1 is better than the second
10145 standard conversion sequence of U2. */
10147 /* Handle list-conversion with the same code even though it isn't always
10148 ranked as a user-defined conversion and it doesn't have a second
10149 standard conversion sequence; it will still have the desired effect.
10150 Specifically, we need to do the reference binding comparison at the
10151 end of this function. */
10153 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
10154 || ics1
->kind
== ck_aggr
|| ics2
->kind
== ck_aggr
)
10159 for (t1
= ics1
; t1
&& t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
10160 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
10161 || t1
->kind
== ck_list
)
10163 for (t2
= ics2
; t2
&& t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
10164 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
10165 || t2
->kind
== ck_list
)
10168 if (!t1
|| !t2
|| t1
->kind
!= t2
->kind
)
10170 else if (t1
->kind
== ck_user
)
10172 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10173 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10179 /* For ambiguous or aggregate conversions, use the target type as
10180 a proxy for the conversion function. */
10181 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10185 /* We can just fall through here, after setting up
10186 FROM_TYPE1 and FROM_TYPE2. */
10187 from_type1
= t1
->type
;
10188 from_type2
= t2
->type
;
10195 /* We're dealing with two standard conversion sequences.
10199 Standard conversion sequence S1 is a better conversion
10200 sequence than standard conversion sequence S2 if
10202 --S1 is a proper subsequence of S2 (comparing the conversion
10203 sequences in the canonical form defined by _over.ics.scs_,
10204 excluding any Lvalue Transformation; the identity
10205 conversion sequence is considered to be a subsequence of
10206 any non-identity conversion sequence */
10209 while (t1
->kind
!= ck_identity
)
10210 t1
= next_conversion (t1
);
10211 from_type1
= t1
->type
;
10214 while (t2
->kind
!= ck_identity
)
10215 t2
= next_conversion (t2
);
10216 from_type2
= t2
->type
;
10219 /* One sequence can only be a subsequence of the other if they start with
10220 the same type. They can start with different types when comparing the
10221 second standard conversion sequence in two user-defined conversion
10223 if (same_type_p (from_type1
, from_type2
))
10225 if (is_subseq (ics1
, ics2
))
10227 if (is_subseq (ics2
, ics1
))
10235 --the rank of S1 is better than the rank of S2 (by the rules
10238 Standard conversion sequences are ordered by their ranks: an Exact
10239 Match is a better conversion than a Promotion, which is a better
10240 conversion than a Conversion.
10242 Two conversion sequences with the same rank are indistinguishable
10243 unless one of the following rules applies:
10245 --A conversion that does not a convert a pointer, pointer to member,
10246 or std::nullptr_t to bool is better than one that does.
10248 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10249 so that we do not have to check it explicitly. */
10250 if (ics1
->rank
< ics2
->rank
)
10252 else if (ics2
->rank
< ics1
->rank
)
10255 to_type1
= ics1
->type
;
10256 to_type2
= ics2
->type
;
10258 /* A conversion from scalar arithmetic type to complex is worse than a
10259 conversion between scalar arithmetic types. */
10260 if (same_type_p (from_type1
, from_type2
)
10261 && ARITHMETIC_TYPE_P (from_type1
)
10262 && ARITHMETIC_TYPE_P (to_type1
)
10263 && ARITHMETIC_TYPE_P (to_type2
)
10264 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10265 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10267 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10273 if (TYPE_PTR_P (from_type1
)
10274 && TYPE_PTR_P (from_type2
)
10275 && TYPE_PTR_P (to_type1
)
10276 && TYPE_PTR_P (to_type2
))
10278 deref_from_type1
= TREE_TYPE (from_type1
);
10279 deref_from_type2
= TREE_TYPE (from_type2
);
10280 deref_to_type1
= TREE_TYPE (to_type1
);
10281 deref_to_type2
= TREE_TYPE (to_type2
);
10283 /* The rules for pointers to members A::* are just like the rules
10284 for pointers A*, except opposite: if B is derived from A then
10285 A::* converts to B::*, not vice versa. For that reason, we
10286 switch the from_ and to_ variables here. */
10287 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10288 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10289 || (TYPE_PTRMEMFUNC_P (from_type1
)
10290 && TYPE_PTRMEMFUNC_P (from_type2
)
10291 && TYPE_PTRMEMFUNC_P (to_type1
)
10292 && TYPE_PTRMEMFUNC_P (to_type2
)))
10294 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10295 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10296 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10297 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10300 if (deref_from_type1
!= NULL_TREE
10301 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10302 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10304 /* This was one of the pointer or pointer-like conversions.
10308 --If class B is derived directly or indirectly from class A,
10309 conversion of B* to A* is better than conversion of B* to
10310 void*, and conversion of A* to void* is better than
10311 conversion of B* to void*. */
10312 if (VOID_TYPE_P (deref_to_type1
)
10313 && VOID_TYPE_P (deref_to_type2
))
10315 if (is_properly_derived_from (deref_from_type1
,
10318 else if (is_properly_derived_from (deref_from_type2
,
10322 else if (VOID_TYPE_P (deref_to_type1
)
10323 || VOID_TYPE_P (deref_to_type2
))
10325 if (same_type_p (deref_from_type1
, deref_from_type2
))
10327 if (VOID_TYPE_P (deref_to_type2
))
10329 if (is_properly_derived_from (deref_from_type1
,
10333 /* We know that DEREF_TO_TYPE1 is `void' here. */
10334 else if (is_properly_derived_from (deref_from_type1
,
10339 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10340 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10344 --If class B is derived directly or indirectly from class A
10345 and class C is derived directly or indirectly from B,
10347 --conversion of C* to B* is better than conversion of C* to
10350 --conversion of B* to A* is better than conversion of C* to
10352 if (same_type_p (deref_from_type1
, deref_from_type2
))
10354 if (is_properly_derived_from (deref_to_type1
,
10357 else if (is_properly_derived_from (deref_to_type2
,
10361 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10363 if (is_properly_derived_from (deref_from_type2
,
10366 else if (is_properly_derived_from (deref_from_type1
,
10372 else if (CLASS_TYPE_P (non_reference (from_type1
))
10373 && same_type_p (from_type1
, from_type2
))
10375 tree from
= non_reference (from_type1
);
10379 --binding of an expression of type C to a reference of type
10380 B& is better than binding an expression of type C to a
10381 reference of type A&
10383 --conversion of C to B is better than conversion of C to A, */
10384 if (is_properly_derived_from (from
, to_type1
)
10385 && is_properly_derived_from (from
, to_type2
))
10387 if (is_properly_derived_from (to_type1
, to_type2
))
10389 else if (is_properly_derived_from (to_type2
, to_type1
))
10393 else if (CLASS_TYPE_P (non_reference (to_type1
))
10394 && same_type_p (to_type1
, to_type2
))
10396 tree to
= non_reference (to_type1
);
10400 --binding of an expression of type B to a reference of type
10401 A& is better than binding an expression of type C to a
10402 reference of type A&,
10404 --conversion of B to A is better than conversion of C to A */
10405 if (is_properly_derived_from (from_type1
, to
)
10406 && is_properly_derived_from (from_type2
, to
))
10408 if (is_properly_derived_from (from_type2
, from_type1
))
10410 else if (is_properly_derived_from (from_type1
, from_type2
))
10417 --S1 and S2 differ only in their qualification conversion and yield
10418 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10419 qualification signature of type T1 is a proper subset of the cv-
10420 qualification signature of type T2 */
10421 if (ics1
->kind
== ck_qual
10422 && ics2
->kind
== ck_qual
10423 && same_type_p (from_type1
, from_type2
))
10425 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10432 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10433 to an implicit object parameter of a non-static member function
10434 declared without a ref-qualifier, and either S1 binds an lvalue
10435 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10436 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10437 draft standard, 13.3.3.2)
10439 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10440 types to which the references refer are the same type except for
10441 top-level cv-qualifiers, and the type to which the reference
10442 initialized by S2 refers is more cv-qualified than the type to
10443 which the reference initialized by S1 refers.
10445 DR 1328 [over.match.best]: the context is an initialization by
10446 conversion function for direct reference binding (13.3.1.6) of a
10447 reference to function type, the return type of F1 is the same kind of
10448 reference (i.e. lvalue or rvalue) as the reference being initialized,
10449 and the return type of F2 is not. */
10451 if (ref_conv1
&& ref_conv2
)
10453 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10454 && (ref_conv1
->rvaluedness_matches_p
10455 != ref_conv2
->rvaluedness_matches_p
)
10456 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10457 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10458 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10460 if (ref_conv1
->bad_p
10461 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10462 TREE_TYPE (ref_conv2
->type
)))
10463 /* Don't prefer a bad conversion that drops cv-quals to a bad
10464 conversion with the wrong rvalueness. */
10466 return (ref_conv1
->rvaluedness_matches_p
10467 - ref_conv2
->rvaluedness_matches_p
);
10470 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10472 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10473 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10474 if (ref_conv1
->bad_p
)
10476 /* Prefer the one that drops fewer cv-quals. */
10477 tree ftype
= next_conversion (ref_conv1
)->type
;
10478 int fquals
= cp_type_quals (ftype
);
10482 return comp_cv_qualification (q2
, q1
);
10486 /* Neither conversion sequence is better than the other. */
10490 /* The source type for this standard conversion sequence. */
10493 source_type (conversion
*t
)
10495 for (;; t
= next_conversion (t
))
10497 if (t
->kind
== ck_user
10498 || t
->kind
== ck_ambig
10499 || t
->kind
== ck_identity
)
10502 gcc_unreachable ();
10505 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10506 a pointer to LOSER and re-running joust to produce the warning if WINNER
10507 is actually used. */
10510 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10512 candidate_warning
*cw
= (candidate_warning
*)
10513 conversion_obstack_alloc (sizeof (candidate_warning
));
10515 cw
->next
= winner
->warnings
;
10516 winner
->warnings
= cw
;
10519 /* CAND is a constructor candidate in joust in C++17 and up. If it copies a
10520 prvalue returned from a conversion function, replace CAND with the candidate
10521 for the conversion and return true. Otherwise, return false. */
10524 joust_maybe_elide_copy (z_candidate
*&cand
)
10526 tree fn
= cand
->fn
;
10527 if (!DECL_COPY_CONSTRUCTOR_P (fn
) && !DECL_MOVE_CONSTRUCTOR_P (fn
))
10529 conversion
*conv
= cand
->convs
[0];
10530 gcc_checking_assert (conv
->kind
== ck_ref_bind
);
10531 conv
= next_conversion (conv
);
10532 if (conv
->kind
== ck_user
&& !TYPE_REF_P (conv
->type
))
10534 gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p
10535 (conv
->type
, DECL_CONTEXT (fn
)));
10536 z_candidate
*uc
= conv
->cand
;
10537 if (DECL_CONV_FN_P (uc
->fn
))
10546 /* Compare two candidates for overloading as described in
10547 [over.match.best]. Return values:
10549 1: cand1 is better than cand2
10550 -1: cand2 is better than cand1
10551 0: cand1 and cand2 are indistinguishable */
10554 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10555 tsubst_flags_t complain
)
10558 int off1
= 0, off2
= 0;
10562 /* Candidates that involve bad conversions are always worse than those
10564 if (cand1
->viable
> cand2
->viable
)
10566 if (cand1
->viable
< cand2
->viable
)
10569 /* If we have two pseudo-candidates for conversions to the same type,
10570 or two candidates for the same function, arbitrarily pick one. */
10571 if (cand1
->fn
== cand2
->fn
10572 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10575 /* Prefer a non-deleted function over an implicitly deleted move
10576 constructor or assignment operator. This differs slightly from the
10577 wording for issue 1402 (which says the move op is ignored by overload
10578 resolution), but this way produces better error messages. */
10579 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10580 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10581 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10583 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10584 && move_fn_p (cand1
->fn
))
10586 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10587 && move_fn_p (cand2
->fn
))
10591 /* a viable function F1
10592 is defined to be a better function than another viable function F2 if
10593 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10594 ICSi(F2), and then */
10596 /* for some argument j, ICSj(F1) is a better conversion sequence than
10599 /* For comparing static and non-static member functions, we ignore
10600 the implicit object parameter of the non-static function. The
10601 standard says to pretend that the static function has an object
10602 parm, but that won't work with operator overloading. */
10603 len
= cand1
->num_convs
;
10604 if (len
!= cand2
->num_convs
)
10606 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10607 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10609 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10610 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10611 /* We're comparing a near-match list constructor and a near-match
10612 non-list constructor. Just treat them as unordered. */
10615 gcc_assert (static_1
!= static_2
);
10626 /* Handle C++17 copy elision in [over.match.ctor] (direct-init) context. The
10627 standard currently says that only constructors are candidates, but if one
10628 copies a prvalue returned by a conversion function we want to treat the
10629 conversion as the candidate instead.
10631 Clang does something similar, as discussed at
10632 http://lists.isocpp.org/core/2017/10/3166.php
10633 http://lists.isocpp.org/core/2019/03/5721.php */
10634 int elided_tiebreaker
= 0;
10635 if (len
== 1 && cxx_dialect
>= cxx17
10636 && DECL_P (cand1
->fn
)
10637 && DECL_COMPLETE_CONSTRUCTOR_P (cand1
->fn
)
10638 && !(cand1
->flags
& LOOKUP_ONLYCONVERTING
))
10640 bool elided1
= joust_maybe_elide_copy (cand1
);
10641 bool elided2
= joust_maybe_elide_copy (cand2
);
10642 /* As a tiebreaker below we will prefer a constructor to a conversion
10643 operator exposed this way. */
10644 elided_tiebreaker
= elided2
- elided1
;
10647 for (i
= 0; i
< len
; ++i
)
10649 conversion
*t1
= cand1
->convs
[i
+ off1
];
10650 conversion
*t2
= cand2
->convs
[i
+ off2
];
10651 int comp
= compare_ics (t1
, t2
);
10655 if ((complain
& tf_warning
)
10657 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10658 == cr_std
+ cr_promotion
)
10659 && t1
->kind
== ck_std
10660 && t2
->kind
== ck_std
10661 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10662 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10663 && (TYPE_PRECISION (t1
->type
)
10664 == TYPE_PRECISION (t2
->type
))
10665 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10666 || (TREE_CODE (next_conversion (t1
)->type
)
10667 == ENUMERAL_TYPE
)))
10669 tree type
= next_conversion (t1
)->type
;
10671 struct z_candidate
*w
, *l
;
10673 type1
= t1
->type
, type2
= t2
->type
,
10674 w
= cand1
, l
= cand2
;
10676 type1
= t2
->type
, type2
= t1
->type
,
10677 w
= cand2
, l
= cand1
;
10681 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10682 type
, type1
, type2
);
10683 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10686 add_warning (w
, l
);
10689 if (winner
&& comp
!= winner
)
10698 /* warn about confusing overload resolution for user-defined conversions,
10699 either between a constructor and a conversion op, or between two
10701 if ((complain
& tf_warning
)
10702 && winner
&& warn_conversion
&& cand1
->second_conv
10703 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10704 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10706 struct z_candidate
*w
, *l
;
10707 bool give_warning
= false;
10710 w
= cand1
, l
= cand2
;
10712 w
= cand2
, l
= cand1
;
10714 /* We don't want to complain about `X::operator T1 ()'
10715 beating `X::operator T2 () const', when T2 is a no less
10716 cv-qualified version of T1. */
10717 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10718 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10720 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10721 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10723 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10728 if (!comp_ptr_ttypes (t
, f
))
10729 give_warning
= true;
10732 give_warning
= true;
10738 tree source
= source_type (w
->convs
[0]);
10739 if (INDIRECT_TYPE_P (source
))
10740 source
= TREE_TYPE (source
);
10741 auto_diagnostic_group d
;
10742 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10743 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10744 source
, w
->second_conv
->type
))
10746 inform (input_location
, " because conversion sequence "
10747 "for the argument is better");
10751 add_warning (w
, l
);
10757 /* Put this tiebreaker first, so that we don't try to look at second_conv of
10758 a constructor candidate that doesn't have one. */
10759 if (elided_tiebreaker
)
10760 return elided_tiebreaker
;
10762 /* DR 495 moved this tiebreaker above the template ones. */
10763 /* or, if not that,
10764 the context is an initialization by user-defined conversion (see
10765 _dcl.init_ and _over.match.user_) and the standard conversion
10766 sequence from the return type of F1 to the destination type (i.e.,
10767 the type of the entity being initialized) is a better conversion
10768 sequence than the standard conversion sequence from the return type
10769 of F2 to the destination type. */
10771 if (cand1
->second_conv
)
10773 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10778 /* or, if not that,
10779 F1 is a non-template function and F2 is a template function
10782 if (!cand1
->template_decl
&& cand2
->template_decl
)
10784 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10787 /* or, if not that,
10788 F1 and F2 are template functions and the function template for F1 is
10789 more specialized than the template for F2 according to the partial
10792 if (cand1
->template_decl
&& cand2
->template_decl
)
10794 winner
= more_specialized_fn
10795 (TI_TEMPLATE (cand1
->template_decl
),
10796 TI_TEMPLATE (cand2
->template_decl
),
10797 /* [temp.func.order]: The presence of unused ellipsis and default
10798 arguments has no effect on the partial ordering of function
10799 templates. add_function_candidate() will not have
10800 counted the "this" argument for constructors. */
10801 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10807 // or, if not that, F1 is more constrained than F2.
10808 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10810 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10815 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10816 if (deduction_guide_p (cand1
->fn
))
10818 gcc_assert (deduction_guide_p (cand2
->fn
));
10819 /* We distinguish between candidates from an explicit deduction guide and
10820 candidates built from a constructor based on DECL_ARTIFICIAL. */
10821 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10822 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10824 return art2
- art1
;
10828 /* Prefer the special copy guide over a declared copy/move
10830 if (copy_guide_p (cand1
->fn
))
10832 if (copy_guide_p (cand2
->fn
))
10835 /* Prefer a candidate generated from a non-template constructor. */
10836 int tg1
= template_guide_p (cand1
->fn
);
10837 int tg2
= template_guide_p (cand2
->fn
);
10843 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10844 for all arguments the corresponding parameters of F1 and F2 have the same
10845 type (CWG 2273/2277). */
10846 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10847 && !DECL_CONV_FN_P (cand1
->fn
)
10848 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10849 && !DECL_CONV_FN_P (cand2
->fn
))
10851 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10852 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10854 bool used1
= false;
10855 bool used2
= false;
10856 if (base1
== base2
)
10857 /* No difference. */;
10858 else if (DERIVED_FROM_P (base1
, base2
))
10860 else if (DERIVED_FROM_P (base2
, base1
))
10863 if (int diff
= used2
- used1
)
10865 for (i
= 0; i
< len
; ++i
)
10867 conversion
*t1
= cand1
->convs
[i
+ off1
];
10868 conversion
*t2
= cand2
->convs
[i
+ off2
];
10869 if (!same_type_p (t1
->type
, t2
->type
))
10877 /* Check whether we can discard a builtin candidate, either because we
10878 have two identical ones or matching builtin and non-builtin candidates.
10880 (Pedantically in the latter case the builtin which matched the user
10881 function should not be added to the overload set, but we spot it here.
10884 ... the builtin candidates include ...
10885 - do not have the same parameter type list as any non-template
10886 non-member candidate. */
10888 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10890 for (i
= 0; i
< len
; ++i
)
10891 if (!same_type_p (cand1
->convs
[i
]->type
,
10892 cand2
->convs
[i
]->type
))
10894 if (i
== cand1
->num_convs
)
10896 if (cand1
->fn
== cand2
->fn
)
10897 /* Two built-in candidates; arbitrarily pick one. */
10899 else if (identifier_p (cand1
->fn
))
10900 /* cand1 is built-in; prefer cand2. */
10903 /* cand2 is built-in; prefer cand1. */
10908 /* For candidates of a multi-versioned function, make the version with
10909 the highest priority win. This version will be checked for dispatching
10910 first. If this version can be inlined into the caller, the front-end
10911 will simply make a direct call to this function. */
10913 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10914 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10915 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10916 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10918 tree f1
= TREE_TYPE (cand1
->fn
);
10919 tree f2
= TREE_TYPE (cand2
->fn
);
10920 tree p1
= TYPE_ARG_TYPES (f1
);
10921 tree p2
= TYPE_ARG_TYPES (f2
);
10923 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10924 is possible that cand1->fn and cand2->fn are function versions but of
10925 different functions. Check types to see if they are versions of the same
10927 if (compparms (p1
, p2
)
10928 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10930 /* Always make the version with the higher priority, more
10931 specialized, win. */
10932 gcc_assert (targetm
.compare_version_priority
);
10933 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10940 /* If the two function declarations represent the same function (this can
10941 happen with declarations in multiple scopes and arg-dependent lookup),
10942 arbitrarily choose one. But first make sure the default args we're
10944 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10945 && equal_functions (cand1
->fn
, cand2
->fn
))
10947 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10948 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10950 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10952 for (i
= 0; i
< len
; ++i
)
10954 /* Don't crash if the fn is variadic. */
10957 parms1
= TREE_CHAIN (parms1
);
10958 parms2
= TREE_CHAIN (parms2
);
10962 parms1
= TREE_CHAIN (parms1
);
10964 parms2
= TREE_CHAIN (parms2
);
10966 for (; parms1
; ++i
)
10968 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10969 TREE_PURPOSE (parms2
)))
10973 if (complain
& tf_error
)
10975 auto_diagnostic_group d
;
10976 if (permerror (input_location
,
10977 "default argument mismatch in "
10978 "overload resolution"))
10980 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10981 " candidate 1: %q#F", cand1
->fn
);
10982 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10983 " candidate 2: %q#F", cand2
->fn
);
10990 add_warning (cand1
, cand2
);
10993 parms1
= TREE_CHAIN (parms1
);
10994 parms2
= TREE_CHAIN (parms2
);
11002 /* Extension: If the worst conversion for one candidate is better than the
11003 worst conversion for the other, take the first. */
11004 if (!pedantic
&& (complain
& tf_warning_or_error
))
11006 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
11007 struct z_candidate
*w
= 0, *l
= 0;
11009 for (i
= 0; i
< len
; ++i
)
11011 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
11012 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
11013 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
11014 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
11017 winner
= 1, w
= cand1
, l
= cand2
;
11019 winner
= -1, w
= cand2
, l
= cand1
;
11022 /* Don't choose a deleted function over ambiguity. */
11023 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
11027 auto_diagnostic_group d
;
11028 if (pedwarn (input_location
, 0,
11029 "ISO C++ says that these are ambiguous, even "
11030 "though the worst conversion for the first is "
11031 "better than the worst conversion for the second:"))
11033 print_z_candidate (input_location
, N_("candidate 1:"), w
);
11034 print_z_candidate (input_location
, N_("candidate 2:"), l
);
11038 add_warning (w
, l
);
11043 gcc_assert (!winner
);
11047 /* Given a list of candidates for overloading, find the best one, if any.
11048 This algorithm has a worst case of O(2n) (winner is last), and a best
11049 case of O(n/2) (totally ambiguous); much better than a sorting
11052 static struct z_candidate
*
11053 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
11055 struct z_candidate
*champ
= candidates
, *challenger
;
11057 int champ_compared_to_predecessor
= 0;
11059 /* Walk through the list once, comparing each current champ to the next
11060 candidate, knocking out a candidate or two with each comparison. */
11062 for (challenger
= champ
->next
; challenger
; )
11064 fate
= joust (champ
, challenger
, 0, complain
);
11066 challenger
= challenger
->next
;
11071 champ
= challenger
->next
;
11074 champ_compared_to_predecessor
= 0;
11078 champ
= challenger
;
11079 champ_compared_to_predecessor
= 1;
11082 challenger
= champ
->next
;
11086 /* Make sure the champ is better than all the candidates it hasn't yet
11087 been compared to. */
11089 for (challenger
= candidates
;
11090 challenger
!= champ
11091 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
11092 challenger
= challenger
->next
)
11094 fate
= joust (champ
, challenger
, 0, complain
);
11102 /* Returns nonzero if things of type FROM can be converted to TO. */
11105 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
11107 tree arg
= NULL_TREE
;
11108 /* implicit_conversion only considers user-defined conversions
11109 if it has an expression for the call argument list. */
11110 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
11111 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
11112 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
11115 /* Returns nonzero if things of type FROM can be converted to TO with a
11116 standard conversion. */
11119 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
11121 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
11124 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
11127 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
11128 tsubst_flags_t complain
)
11134 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11135 p
= conversion_obstack_alloc (0);
11136 /* We want to discard any access checks done for this test,
11137 as we might not be in the appropriate access context and
11138 we'll do the check again when we actually perform the
11140 push_deferring_access_checks (dk_deferred
);
11142 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11144 ok_p
= (t
&& !t
->bad_p
);
11146 /* Discard the access checks now. */
11147 pop_deferring_access_checks ();
11148 /* Free all the conversions we allocated. */
11149 obstack_free (&conversion_obstack
, p
);
11154 /* Like can_convert_arg, but allows dubious conversions as well. */
11157 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
11158 tsubst_flags_t complain
)
11163 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11164 p
= conversion_obstack_alloc (0);
11165 /* Try to perform the conversion. */
11166 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11168 /* Free all the conversions we allocated. */
11169 obstack_free (&conversion_obstack
, p
);
11174 /* Convert EXPR to TYPE. Return the converted expression.
11176 Note that we allow bad conversions here because by the time we get to
11177 this point we are committed to doing the conversion. If we end up
11178 doing a bad conversion, convert_like will complain. */
11181 perform_implicit_conversion_flags (tree type
, tree expr
,
11182 tsubst_flags_t complain
, int flags
)
11186 location_t loc
= cp_expr_loc_or_input_loc (expr
);
11188 if (TYPE_REF_P (type
))
11189 expr
= mark_lvalue_use (expr
);
11191 expr
= mark_rvalue_use (expr
);
11193 if (error_operand_p (expr
))
11194 return error_mark_node
;
11196 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11197 p
= conversion_obstack_alloc (0);
11199 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11200 /*c_cast_p=*/false,
11205 if (complain
& tf_error
)
11207 /* If expr has unknown type, then it is an overloaded function.
11208 Call instantiate_type to get good error messages. */
11209 if (TREE_TYPE (expr
) == unknown_type_node
)
11210 instantiate_type (type
, expr
, complain
);
11211 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
11212 /* We gave an error. */;
11215 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
11216 gcc_rich_location
rich_loc (loc
, &label
);
11217 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
11218 expr
, TREE_TYPE (expr
), type
);
11221 expr
= error_mark_node
;
11223 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11225 /* In a template, we are only concerned about determining the
11226 type of non-dependent expressions, so we do not have to
11227 perform the actual conversion. But for initializers, we
11228 need to be able to perform it at instantiation
11229 (or instantiate_non_dependent_expr) time. */
11230 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11231 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11232 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11233 if (flags
& LOOKUP_NO_NARROWING
)
11234 IMPLICIT_CONV_EXPR_BRACED_INIT (expr
) = true;
11237 expr
= convert_like (conv
, expr
, complain
);
11239 /* Free all the conversions we allocated. */
11240 obstack_free (&conversion_obstack
, p
);
11246 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11248 return perform_implicit_conversion_flags (type
, expr
, complain
,
11252 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11253 permitted. If the conversion is valid, the converted expression is
11254 returned. Otherwise, NULL_TREE is returned, except in the case
11255 that TYPE is a class type; in that case, an error is issued. If
11256 C_CAST_P is true, then this direct-initialization is taking
11257 place as part of a static_cast being attempted as part of a C-style
11261 perform_direct_initialization_if_possible (tree type
,
11264 tsubst_flags_t complain
)
11269 if (type
== error_mark_node
|| error_operand_p (expr
))
11270 return error_mark_node
;
11273 If the destination type is a (possibly cv-qualified) class type:
11275 -- If the initialization is direct-initialization ...,
11276 constructors are considered. ... If no constructor applies, or
11277 the overload resolution is ambiguous, the initialization is
11279 if (CLASS_TYPE_P (type
))
11281 releasing_vec
args (make_tree_vector_single (expr
));
11282 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11283 &args
, type
, LOOKUP_NORMAL
, complain
);
11284 return build_cplus_new (type
, expr
, complain
);
11287 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11288 p
= conversion_obstack_alloc (0);
11290 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11292 LOOKUP_NORMAL
, complain
);
11293 if (!conv
|| conv
->bad_p
)
11295 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11297 /* In a template, we are only concerned about determining the
11298 type of non-dependent expressions, so we do not have to
11299 perform the actual conversion. But for initializers, we
11300 need to be able to perform it at instantiation
11301 (or instantiate_non_dependent_expr) time. */
11302 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11303 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11306 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11307 /*issue_conversion_warnings=*/false,
11311 /* Free all the conversions we allocated. */
11312 obstack_free (&conversion_obstack
, p
);
11317 /* When initializing a reference that lasts longer than a full-expression,
11318 this special rule applies:
11322 The temporary to which the reference is bound or the temporary
11323 that is the complete object to which the reference is bound
11324 persists for the lifetime of the reference.
11326 The temporaries created during the evaluation of the expression
11327 initializing the reference, except the temporary to which the
11328 reference is bound, are destroyed at the end of the
11329 full-expression in which they are created.
11331 In that case, we store the converted expression into a new
11332 VAR_DECL in a new scope.
11334 However, we want to be careful not to create temporaries when
11335 they are not required. For example, given:
11338 struct D : public B {};
11342 there is no need to copy the return value from "f"; we can just
11343 extend its lifetime. Similarly, given:
11346 struct T { operator S(); };
11350 we can extend the lifetime of the return value of the conversion
11353 The next several functions are involved in this lifetime extension. */
11355 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11356 reference is being bound to a temporary. Create and return a new
11357 VAR_DECL with the indicated TYPE; this variable will store the value to
11358 which the reference is bound. */
11361 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11363 tree var
= create_temporary_var (type
);
11365 /* Register the variable. */
11367 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11369 /* Namespace-scope or local static; give it a mangled name. */
11371 /* If an initializer is visible to multiple translation units, those
11372 translation units must agree on the addresses of the
11373 temporaries. Therefore the temporaries must be given a consistent name
11374 and vague linkage. The mangled name of a temporary is the name of the
11375 non-temporary object in whose initializer they appear, prefixed with
11376 GR and suffixed with a sequence number mangled using the usual rules
11377 for a seq-id. Temporaries are numbered with a pre-order, depth-first,
11378 left-to-right walk of the complete initializer. */
11380 TREE_STATIC (var
) = TREE_STATIC (decl
);
11381 TREE_PUBLIC (var
) = TREE_PUBLIC (decl
);
11382 if (vague_linkage_p (decl
))
11383 comdat_linkage (var
);
11385 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11386 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11388 tree name
= mangle_ref_init_variable (decl
);
11389 DECL_NAME (var
) = name
;
11390 SET_DECL_ASSEMBLER_NAME (var
, name
);
11393 /* Create a new cleanup level if necessary. */
11394 maybe_push_cleanup_level (type
);
11396 return pushdecl (var
);
11399 /* EXPR is the initializer for a variable DECL of reference or
11400 std::initializer_list type. Create, push and return a new VAR_DECL
11401 for the initializer so that it will live as long as DECL. Any
11402 cleanup for the new variable is returned through CLEANUP, and the
11403 code to initialize the new variable is returned through INITP. */
11406 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11413 /* Create the temporary variable. */
11414 type
= TREE_TYPE (expr
);
11415 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11416 layout_decl (var
, 0);
11417 /* If the rvalue is the result of a function call it will be
11418 a TARGET_EXPR. If it is some other construct (such as a
11419 member access expression where the underlying object is
11420 itself the result of a function call), turn it into a
11421 TARGET_EXPR here. It is important that EXPR be a
11422 TARGET_EXPR below since otherwise the INIT_EXPR will
11423 attempt to make a bitwise copy of EXPR to initialize
11425 if (TREE_CODE (expr
) != TARGET_EXPR
)
11426 expr
= get_target_expr (expr
);
11428 if (TREE_CODE (decl
) == FIELD_DECL
11429 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11431 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11432 "until the constructor exits", decl
);
11433 TREE_NO_WARNING (decl
) = true;
11436 /* Recursively extend temps in this initializer. */
11437 TARGET_EXPR_INITIAL (expr
)
11438 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11440 /* Any reference temp has a non-trivial initializer. */
11441 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11443 /* If the initializer is constant, put it in DECL_INITIAL so we get
11444 static initialization and use in constant expressions. */
11445 init
= maybe_constant_init (expr
);
11446 /* As in store_init_value. */
11447 init
= cp_fully_fold (init
);
11448 if (TREE_CONSTANT (init
))
11450 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11452 /* 5.19 says that a constant expression can include an
11453 lvalue-rvalue conversion applied to "a glvalue of literal type
11454 that refers to a non-volatile temporary object initialized
11455 with a constant expression". Rather than try to communicate
11456 that this VAR_DECL is a temporary, just mark it constexpr. */
11457 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11458 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11459 TREE_CONSTANT (var
) = true;
11460 TREE_READONLY (var
) = true;
11462 DECL_INITIAL (var
) = init
;
11466 /* Create the INIT_EXPR that will initialize the temporary
11468 init
= split_nonconstant_init (var
, expr
);
11469 if (at_function_scope_p ())
11471 add_decl_expr (var
);
11473 if (TREE_STATIC (var
))
11474 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11477 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11479 vec_safe_push (*cleanups
, cleanup
);
11482 /* We must be careful to destroy the temporary only
11483 after its initialization has taken place. If the
11484 initialization throws an exception, then the
11485 destructor should not be run. We cannot simply
11486 transform INIT into something like:
11488 (INIT, ({ CLEANUP_STMT; }))
11490 because emit_local_var always treats the
11491 initializer as a full-expression. Thus, the
11492 destructor would run too early; it would run at the
11493 end of initializing the reference variable, rather
11494 than at the end of the block enclosing the
11495 reference variable.
11497 The solution is to pass back a cleanup expression
11498 which the caller is responsible for attaching to
11499 the statement tree. */
11503 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11504 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11506 if (CP_DECL_THREAD_LOCAL_P (var
))
11507 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11510 static_aggregates
= tree_cons (NULL_TREE
, var
,
11511 static_aggregates
);
11514 /* Check whether the dtor is callable. */
11515 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11517 /* Avoid -Wunused-variable warning (c++/38958). */
11518 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11520 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11526 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11527 initializing a variable of that TYPE. */
11530 initialize_reference (tree type
, tree expr
,
11531 int flags
, tsubst_flags_t complain
)
11535 location_t loc
= cp_expr_loc_or_input_loc (expr
);
11537 if (type
== error_mark_node
|| error_operand_p (expr
))
11538 return error_mark_node
;
11540 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11541 p
= conversion_obstack_alloc (0);
11543 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11545 if (!conv
|| conv
->bad_p
)
11547 if (complain
& tf_error
)
11550 convert_like (conv
, expr
, complain
);
11551 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11552 && !TYPE_REF_IS_RVALUE (type
)
11553 && !lvalue_p (expr
))
11554 error_at (loc
, "invalid initialization of non-const reference of "
11555 "type %qH from an rvalue of type %qI",
11556 type
, TREE_TYPE (expr
));
11558 error_at (loc
, "invalid initialization of reference of type "
11559 "%qH from expression of type %qI", type
,
11562 return error_mark_node
;
11565 if (conv
->kind
== ck_ref_bind
)
11566 /* Perform the conversion. */
11567 expr
= convert_like (conv
, expr
, complain
);
11568 else if (conv
->kind
== ck_ambig
)
11569 /* We gave an error in build_user_type_conversion_1. */
11570 expr
= error_mark_node
;
11572 gcc_unreachable ();
11574 /* Free all the conversions we allocated. */
11575 obstack_free (&conversion_obstack
, p
);
11580 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11581 which is bound either to a reference or a std::initializer_list. */
11584 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11589 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11591 TREE_OPERAND (sub
, 1)
11592 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11595 if (TREE_CODE (sub
) != ADDR_EXPR
)
11597 /* Deal with binding to a subobject. */
11598 for (p
= &TREE_OPERAND (sub
, 0);
11599 (TREE_CODE (*p
) == COMPONENT_REF
11600 || TREE_CODE (*p
) == ARRAY_REF
); )
11601 p
= &TREE_OPERAND (*p
, 0);
11602 if (TREE_CODE (*p
) == TARGET_EXPR
)
11604 tree subinit
= NULL_TREE
;
11605 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11606 recompute_tree_invariant_for_addr_expr (sub
);
11608 init
= fold_convert (TREE_TYPE (init
), sub
);
11610 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11615 /* INIT is part of the initializer for DECL. If there are any
11616 reference or initializer lists being initialized, extend their
11617 lifetime to match that of DECL. */
11620 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11622 tree type
= TREE_TYPE (init
);
11623 if (processing_template_decl
)
11625 if (TYPE_REF_P (type
))
11626 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11630 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11631 ctor
= TARGET_EXPR_INITIAL (ctor
);
11632 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11634 if (is_std_init_list (type
))
11636 /* The temporary array underlying a std::initializer_list
11637 is handled like a reference temporary. */
11638 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11639 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11640 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11645 constructor_elt
*p
;
11646 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11647 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11648 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11650 recompute_constructor_flags (ctor
);
11651 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11652 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11659 /* Returns true iff an initializer for TYPE could contain temporaries that
11660 need to be extended because they are bound to references or
11661 std::initializer_list. */
11664 type_has_extended_temps (tree type
)
11666 type
= strip_array_types (type
);
11667 if (TYPE_REF_P (type
))
11669 if (CLASS_TYPE_P (type
))
11671 if (is_std_init_list (type
))
11673 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11674 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11675 if (type_has_extended_temps (TREE_TYPE (f
)))
11681 /* Returns true iff TYPE is some variant of std::initializer_list. */
11684 is_std_init_list (tree type
)
11686 if (!TYPE_P (type
))
11688 if (cxx_dialect
== cxx98
)
11690 /* Look through typedefs. */
11691 type
= TYPE_MAIN_VARIANT (type
);
11692 return (CLASS_TYPE_P (type
)
11693 && CP_TYPE_CONTEXT (type
) == std_node
11694 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11697 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11698 will accept an argument list of a single std::initializer_list<T>. */
11701 is_list_ctor (tree decl
)
11703 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11706 if (!args
|| args
== void_list_node
)
11709 arg
= non_reference (TREE_VALUE (args
));
11710 if (!is_std_init_list (arg
))
11713 args
= TREE_CHAIN (args
);
11715 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11716 /* There are more non-defaulted parms. */
11722 #include "gt-cp-call.h"