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_loc (expr
, input_location
);
4189 if (error_operand_p (expr
))
4190 return error_mark_node
;
4192 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4193 p
= conversion_obstack_alloc (0);
4195 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4196 /*c_cast_p=*/false, flags
, complain
);
4198 /* A converted constant expression of type T is an expression, implicitly
4199 converted to type T, where the converted expression is a constant
4200 expression and the implicit conversion sequence contains only
4202 * user-defined conversions,
4203 * lvalue-to-rvalue conversions (7.1),
4204 * array-to-pointer conversions (7.2),
4205 * function-to-pointer conversions (7.3),
4206 * qualification conversions (7.5),
4207 * integral promotions (7.6),
4208 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4209 * null pointer conversions (7.11) from std::nullptr_t,
4210 * null member pointer conversions (7.12) from std::nullptr_t, and
4211 * function pointer conversions (7.13),
4213 and where the reference binding (if any) binds directly. */
4215 for (conversion
*c
= conv
;
4216 conv
&& c
->kind
!= ck_identity
;
4217 c
= next_conversion (c
))
4221 /* A conversion function is OK. If it isn't constexpr, we'll
4222 complain later that the argument isn't constant. */
4224 /* The lvalue-to-rvalue conversion is OK. */
4226 /* Array-to-pointer and function-to-pointer. */
4228 /* Function pointer conversions. */
4230 /* Qualification conversions. */
4235 if (c
->need_temporary_p
)
4237 if (complain
& tf_error
)
4238 error_at (loc
, "initializing %qH with %qI in converted "
4239 "constant expression does not bind directly",
4240 type
, next_conversion (c
)->type
);
4249 t
= next_conversion (c
)->type
;
4250 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4251 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4252 /* Integral promotion or conversion. */
4254 if (NULLPTR_TYPE_P (t
))
4255 /* Conversion from nullptr to pointer or pointer-to-member. */
4258 if (complain
& tf_error
)
4259 error_at (loc
, "conversion from %qH to %qI in a "
4260 "converted constant expression", t
, type
);
4269 /* Avoid confusing convert_nontype_argument by introducing
4270 a redundant conversion to the same reference type. */
4271 if (conv
&& conv
->kind
== ck_ref_bind
4272 && REFERENCE_REF_P (expr
))
4274 tree ref
= TREE_OPERAND (expr
, 0);
4275 if (same_type_p (type
, TREE_TYPE (ref
)))
4281 conv
->check_narrowing
= true;
4282 conv
->check_narrowing_const_only
= true;
4283 expr
= convert_like (conv
, expr
, complain
);
4287 if (complain
& tf_error
)
4288 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4289 TREE_TYPE (expr
), type
);
4290 expr
= error_mark_node
;
4293 /* Free all the conversions we allocated. */
4294 obstack_free (&conversion_obstack
, p
);
4299 /* Subroutine of convert_nontype_argument.
4301 EXPR is an expression used in a context that requires a converted
4302 constant-expression, such as a template non-type parameter. Do any
4303 necessary conversions (that are permitted for converted
4304 constant-expressions) to convert it to the desired type.
4306 This function doesn't consider explicit conversion functions. If
4307 you mean to use "a contextually converted constant expression of type
4308 bool", use build_converted_constant_bool_expr.
4310 If conversion is successful, returns the converted expression;
4311 otherwise, returns error_mark_node. */
4314 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4316 return build_converted_constant_expr_internal (type
, expr
, LOOKUP_IMPLICIT
,
4320 /* Used to create "a contextually converted constant expression of type
4321 bool". This differs from build_converted_constant_expr in that it
4322 also considers explicit conversion functions. */
4325 build_converted_constant_bool_expr (tree expr
, tsubst_flags_t complain
)
4327 return build_converted_constant_expr_internal (boolean_type_node
, expr
,
4328 LOOKUP_NORMAL
, complain
);
4331 /* Do any initial processing on the arguments to a function call. */
4333 static vec
<tree
, va_gc
> *
4334 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4339 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4341 if (error_operand_p (arg
))
4343 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4345 if (complain
& tf_error
)
4346 error ("invalid use of void expression");
4349 else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg
), arg
, complain
))
4355 /* Perform overload resolution on FN, which is called with the ARGS.
4357 Return the candidate function selected by overload resolution, or
4358 NULL if the event that overload resolution failed. In the case
4359 that overload resolution fails, *CANDIDATES will be the set of
4360 candidates considered, and ANY_VIABLE_P will be set to true or
4361 false to indicate whether or not any of the candidates were
4364 The ARGS should already have gone through RESOLVE_ARGS before this
4365 function is called. */
4367 static struct z_candidate
*
4368 perform_overload_resolution (tree fn
,
4369 const vec
<tree
, va_gc
> *args
,
4370 struct z_candidate
**candidates
,
4371 bool *any_viable_p
, tsubst_flags_t complain
)
4373 struct z_candidate
*cand
;
4374 tree explicit_targs
;
4377 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4379 explicit_targs
= NULL_TREE
;
4383 *any_viable_p
= true;
4386 gcc_assert (OVL_P (fn
) || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4388 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4390 explicit_targs
= TREE_OPERAND (fn
, 1);
4391 fn
= TREE_OPERAND (fn
, 0);
4395 /* Add the various candidate functions. */
4396 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4397 explicit_targs
, template_only
,
4398 /*conversion_path=*/NULL_TREE
,
4399 /*access_path=*/NULL_TREE
,
4401 candidates
, complain
);
4403 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4405 cand
= tourney (*candidates
, complain
);
4409 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4413 /* Print an error message about being unable to build a call to FN with
4414 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4415 be located; CANDIDATES is a possibly empty list of such
4419 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4420 struct z_candidate
*candidates
)
4422 tree targs
= NULL_TREE
;
4423 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4425 targs
= TREE_OPERAND (fn
, 1);
4426 fn
= TREE_OPERAND (fn
, 0);
4428 tree name
= OVL_NAME (fn
);
4429 location_t loc
= location_of (name
);
4431 name
= lookup_template_function (name
, targs
);
4433 auto_diagnostic_group d
;
4434 if (!any_strictly_viable (candidates
))
4435 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4436 name
, build_tree_list_vec (args
));
4438 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4439 name
, build_tree_list_vec (args
));
4441 print_z_candidates (loc
, candidates
);
4444 /* Return an expression for a call to FN (a namespace-scope function,
4445 or a static member function) with the ARGS. This may change
4449 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4450 tsubst_flags_t complain
)
4452 struct z_candidate
*candidates
, *cand
;
4457 if (args
!= NULL
&& *args
!= NULL
)
4459 *args
= resolve_args (*args
, complain
);
4461 return error_mark_node
;
4465 tm_malloc_replacement (fn
);
4467 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4468 p
= conversion_obstack_alloc (0);
4470 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4475 if (complain
& tf_error
)
4477 // If there is a single (non-viable) function candidate,
4478 // let the error be diagnosed by cp_build_function_call_vec.
4479 if (!any_viable_p
&& candidates
&& ! candidates
->next
4480 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4481 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4483 // Otherwise, emit notes for non-viable candidates.
4484 print_error_for_call_failure (fn
, *args
, candidates
);
4486 result
= error_mark_node
;
4490 int flags
= LOOKUP_NORMAL
;
4491 /* If fn is template_id_expr, the call has explicit template arguments
4492 (e.g. func<int>(5)), communicate this info to build_over_call
4493 through flags so that later we can use it to decide whether to warn
4494 about peculiar null pointer conversion. */
4495 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4497 /* If overload resolution selects a specialization of a
4498 function concept for non-dependent template arguments,
4499 the expression is true if the constraints are satisfied
4500 and false otherwise.
4502 NOTE: This is an extension of Concepts Lite TS that
4503 allows constraints to be used in expressions. */
4504 if (flag_concepts
&& !processing_template_decl
)
4506 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4507 tree targs
= DECL_TI_ARGS (cand
->fn
);
4508 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4509 if (DECL_DECLARED_CONCEPT_P (decl
))
4510 return evaluate_function_concept (decl
, targs
);
4513 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4516 result
= build_over_call (cand
, flags
, complain
);
4519 /* Free all the conversions we allocated. */
4520 obstack_free (&conversion_obstack
, p
);
4525 /* Build a call to a global operator new. FNNAME is the name of the
4526 operator (either "operator new" or "operator new[]") and ARGS are
4527 the arguments provided. This may change ARGS. *SIZE points to the
4528 total number of bytes required by the allocation, and is updated if
4529 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4530 be used. If this function determines that no cookie should be
4531 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4532 is not NULL_TREE, it is evaluated before calculating the final
4533 array size, and if it fails, the array size is replaced with
4534 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4535 is non-NULL, it will be set, upon return, to the allocation
4539 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4540 tree
*size
, tree
*cookie_size
,
4541 tree align_arg
, tree size_check
,
4542 tree
*fn
, tsubst_flags_t complain
)
4544 tree original_size
= *size
;
4546 struct z_candidate
*candidates
;
4547 struct z_candidate
*cand
= NULL
;
4552 /* Set to (size_t)-1 if the size check fails. */
4553 if (size_check
!= NULL_TREE
)
4555 tree errval
= TYPE_MAX_VALUE (sizetype
);
4556 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4557 errval
= throw_bad_array_new_length ();
4558 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4559 original_size
, errval
);
4561 vec_safe_insert (*args
, 0, *size
);
4562 *args
= resolve_args (*args
, complain
);
4564 return error_mark_node
;
4570 If this lookup fails to find the name, or if the allocated type
4571 is not a class type, the allocation function's name is looked
4572 up in the global scope.
4574 we disregard block-scope declarations of "operator new". */
4575 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4576 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4580 vec
<tree
, va_gc
>* align_args
4581 = vec_copy_and_insert (*args
, align_arg
, 1);
4582 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4583 &any_viable_p
, tf_none
);
4586 /* If no aligned allocation function matches, try again without the
4590 /* Figure out what function is being called. */
4592 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4595 /* If no suitable function could be found, issue an error message
4599 if (complain
& tf_error
)
4600 print_error_for_call_failure (fns
, *args
, candidates
);
4601 return error_mark_node
;
4604 /* If a cookie is required, add some extra space. Whether
4605 or not a cookie is required cannot be determined until
4606 after we know which function was called. */
4609 bool use_cookie
= true;
4612 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4613 /* Skip the size_t parameter. */
4614 arg_types
= TREE_CHAIN (arg_types
);
4615 /* Check the remaining parameters (if any). */
4617 && TREE_CHAIN (arg_types
) == void_list_node
4618 && same_type_p (TREE_VALUE (arg_types
),
4621 /* If we need a cookie, adjust the number of bytes allocated. */
4624 /* Update the total size. */
4625 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4628 /* Set to (size_t)-1 if the size check fails. */
4629 gcc_assert (size_check
!= NULL_TREE
);
4630 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4631 *size
, TYPE_MAX_VALUE (sizetype
));
4633 /* Update the argument list to reflect the adjusted size. */
4634 (**args
)[0] = *size
;
4637 *cookie_size
= NULL_TREE
;
4640 /* Tell our caller which function we decided to call. */
4644 /* Build the CALL_EXPR. */
4645 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4648 /* Build a new call to operator(). This may change ARGS. */
4651 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4653 struct z_candidate
*candidates
= 0, *cand
;
4654 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4656 tree result
= NULL_TREE
;
4659 obj
= mark_lvalue_use (obj
);
4661 if (error_operand_p (obj
))
4662 return error_mark_node
;
4664 tree type
= TREE_TYPE (obj
);
4666 obj
= prep_operand (obj
);
4668 if (TYPE_PTRMEMFUNC_P (type
))
4670 if (complain
& tf_error
)
4671 /* It's no good looking for an overloaded operator() on a
4672 pointer-to-member-function. */
4673 error ("pointer-to-member function %qE cannot be called without "
4674 "an object; consider using %<.*%> or %<->*%>", obj
);
4675 return error_mark_node
;
4678 if (TYPE_BINFO (type
))
4680 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4681 if (fns
== error_mark_node
)
4682 return error_mark_node
;
4687 if (args
!= NULL
&& *args
!= NULL
)
4689 *args
= resolve_args (*args
, complain
);
4691 return error_mark_node
;
4694 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4695 p
= conversion_obstack_alloc (0);
4699 first_mem_arg
= obj
;
4701 add_candidates (BASELINK_FUNCTIONS (fns
),
4702 first_mem_arg
, *args
, NULL_TREE
,
4704 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4705 LOOKUP_NORMAL
, &candidates
, complain
);
4708 convs
= lookup_conversions (type
);
4710 for (; convs
; convs
= TREE_CHAIN (convs
))
4712 tree totype
= TREE_TYPE (convs
);
4714 if (TYPE_PTRFN_P (totype
)
4715 || TYPE_REFFN_P (totype
)
4716 || (TYPE_REF_P (totype
)
4717 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4718 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4722 if (DECL_NONCONVERTING_P (fn
))
4725 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4726 add_template_conv_candidate
4727 (&candidates
, fn
, obj
, *args
, totype
,
4728 /*access_path=*/NULL_TREE
,
4729 /*conversion_path=*/NULL_TREE
, complain
);
4731 add_conv_candidate (&candidates
, fn
, obj
,
4732 *args
, /*conversion_path=*/NULL_TREE
,
4733 /*access_path=*/NULL_TREE
, complain
);
4737 /* Be strict here because if we choose a bad conversion candidate, the
4738 errors we get won't mention the call context. */
4739 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4742 if (complain
& tf_error
)
4744 auto_diagnostic_group d
;
4745 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4746 build_tree_list_vec (*args
));
4747 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4749 result
= error_mark_node
;
4753 cand
= tourney (candidates
, complain
);
4756 if (complain
& tf_error
)
4758 auto_diagnostic_group d
;
4759 error ("call of %<(%T) (%A)%> is ambiguous",
4760 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4761 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4763 result
= error_mark_node
;
4765 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4766 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4767 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4768 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4771 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4772 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4776 gcc_checking_assert (TYPE_P (cand
->fn
));
4777 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4779 obj
= convert_from_reference (obj
);
4780 result
= cp_build_function_call_vec (obj
, args
, complain
);
4784 /* Free all the conversions we allocated. */
4785 obstack_free (&conversion_obstack
, p
);
4790 /* Wrapper for above. */
4793 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4796 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4797 ret
= build_op_call_1 (obj
, args
, complain
);
4798 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4802 /* Called by op_error to prepare format strings suitable for the error
4803 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4804 and a suffix (controlled by NTYPES). */
4807 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4811 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4812 : G_("no match for "), errmsg
, NULL
);
4815 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4816 else if (ntypes
== 2)
4817 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4819 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4825 op_error (const op_location_t
&loc
,
4826 enum tree_code code
, enum tree_code code2
,
4827 tree arg1
, tree arg2
, tree arg3
, bool match
)
4829 bool assop
= code
== MODIFY_EXPR
;
4830 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4835 if (flag_diagnostics_show_caret
)
4836 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4838 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4840 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4841 "in %<%E ? %E : %E%>"), 3, match
),
4843 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4846 case POSTINCREMENT_EXPR
:
4847 case POSTDECREMENT_EXPR
:
4848 if (flag_diagnostics_show_caret
)
4849 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4850 opname
, TREE_TYPE (arg1
));
4852 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4854 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4858 if (flag_diagnostics_show_caret
)
4859 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4860 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4862 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4864 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4869 if (flag_diagnostics_show_caret
)
4870 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4871 opname
, TREE_TYPE (arg1
));
4873 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4874 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4879 if (flag_diagnostics_show_caret
)
4881 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4883 op_error_string (G_("%<operator%s%>"), 2, match
),
4884 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4887 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4889 opname
, arg1
, opname
, arg2
,
4890 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4892 if (flag_diagnostics_show_caret
)
4893 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4894 opname
, TREE_TYPE (arg1
));
4896 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4898 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4903 /* Return the implicit conversion sequence that could be used to
4904 convert E1 to E2 in [expr.cond]. */
4907 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4909 tree t1
= non_reference (TREE_TYPE (e1
));
4910 tree t2
= non_reference (TREE_TYPE (e2
));
4916 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4917 implicitly converted (clause _conv_) to the type "lvalue reference to
4918 T2", subject to the constraint that in the conversion the
4919 reference must bind directly (_dcl.init.ref_) to an lvalue.
4921 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4922 implicitly converted to the type "rvalue reference to T2", subject to
4923 the constraint that the reference must bind directly. */
4926 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4927 conv
= implicit_conversion (rtype
,
4931 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4932 |LOOKUP_ONLYCONVERTING
,
4934 if (conv
&& !conv
->bad_p
)
4938 /* If E2 is a prvalue or if neither of the conversions above can be done
4939 and at least one of the operands has (possibly cv-qualified) class
4941 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4946 If E1 and E2 have class type, and the underlying class types are
4947 the same or one is a base class of the other: E1 can be converted
4948 to match E2 if the class of T2 is the same type as, or a base
4949 class of, the class of T1, and the cv-qualification of T2 is the
4950 same cv-qualification as, or a greater cv-qualification than, the
4951 cv-qualification of T1. If the conversion is applied, E1 is
4952 changed to an rvalue of type T2 that still refers to the original
4953 source class object (or the appropriate subobject thereof). */
4954 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4955 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4957 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4959 conv
= build_identity_conv (t1
, e1
);
4960 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4961 TYPE_MAIN_VARIANT (t2
)))
4962 conv
= build_conv (ck_base
, t2
, conv
);
4964 conv
= build_conv (ck_rvalue
, t2
, conv
);
4973 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4974 converted to the type that expression E2 would have if E2 were
4975 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4976 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4977 LOOKUP_IMPLICIT
, complain
);
4980 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4981 arguments to the conditional expression. */
4984 build_conditional_expr_1 (const op_location_t
&loc
,
4985 tree arg1
, tree arg2
, tree arg3
,
4986 tsubst_flags_t complain
)
4990 tree result
= NULL_TREE
;
4991 tree result_type
= NULL_TREE
;
4992 bool is_glvalue
= true;
4993 struct z_candidate
*candidates
= 0;
4994 struct z_candidate
*cand
;
4996 tree orig_arg2
, orig_arg3
;
4998 /* As a G++ extension, the second argument to the conditional can be
4999 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
5000 c'.) If the second operand is omitted, make sure it is
5001 calculated only once. */
5004 if (complain
& tf_error
)
5005 pedwarn (loc
, OPT_Wpedantic
,
5006 "ISO C++ forbids omitting the middle term of "
5007 "a %<?:%> expression");
5009 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
5010 warn_for_omitted_condop (loc
, arg1
);
5012 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
5013 if (lvalue_p (arg1
))
5014 arg2
= arg1
= cp_stabilize_reference (arg1
);
5016 arg2
= arg1
= cp_save_expr (arg1
);
5019 /* If something has already gone wrong, just pass that fact up the
5021 if (error_operand_p (arg1
)
5022 || error_operand_p (arg2
)
5023 || error_operand_p (arg3
))
5024 return error_mark_node
;
5029 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
5031 tree arg1_type
= TREE_TYPE (arg1
);
5033 /* If arg1 is another cond_expr choosing between -1 and 0,
5034 then we can use its comparison. It may help to avoid
5035 additional comparison, produce more accurate diagnostics
5036 and enables folding. */
5037 if (TREE_CODE (arg1
) == VEC_COND_EXPR
5038 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
5039 && integer_zerop (TREE_OPERAND (arg1
, 2)))
5040 arg1
= TREE_OPERAND (arg1
, 0);
5042 arg1
= force_rvalue (arg1
, complain
);
5043 arg2
= force_rvalue (arg2
, complain
);
5044 arg3
= force_rvalue (arg3
, complain
);
5046 /* force_rvalue can return error_mark on valid arguments. */
5047 if (error_operand_p (arg1
)
5048 || error_operand_p (arg2
)
5049 || error_operand_p (arg3
))
5050 return error_mark_node
;
5052 arg2_type
= TREE_TYPE (arg2
);
5053 arg3_type
= TREE_TYPE (arg3
);
5055 if (!VECTOR_TYPE_P (arg2_type
)
5056 && !VECTOR_TYPE_P (arg3_type
))
5058 /* Rely on the error messages of the scalar version. */
5059 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
5060 orig_arg2
, orig_arg3
, complain
);
5061 if (scal
== error_mark_node
)
5062 return error_mark_node
;
5063 tree stype
= TREE_TYPE (scal
);
5064 tree ctype
= TREE_TYPE (arg1_type
);
5065 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
5066 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
5068 if (complain
& tf_error
)
5069 error_at (loc
, "inferred scalar type %qT is not an integer or "
5070 "floating-point type of the same size as %qT", stype
,
5071 COMPARISON_CLASS_P (arg1
)
5072 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
5074 return error_mark_node
;
5077 tree vtype
= build_opaque_vector_type (stype
,
5078 TYPE_VECTOR_SUBPARTS (arg1_type
));
5079 /* We could pass complain & tf_warning to unsafe_conversion_p,
5080 but the warnings (like Wsign-conversion) have already been
5081 given by the scalar build_conditional_expr_1. We still check
5082 unsafe_conversion_p to forbid truncating long long -> float. */
5083 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
5085 if (complain
& tf_error
)
5086 error_at (loc
, "conversion of scalar %qH to vector %qI "
5087 "involves truncation", arg2_type
, vtype
);
5088 return error_mark_node
;
5090 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
5092 if (complain
& tf_error
)
5093 error_at (loc
, "conversion of scalar %qH to vector %qI "
5094 "involves truncation", arg3_type
, vtype
);
5095 return error_mark_node
;
5098 arg2
= cp_convert (stype
, arg2
, complain
);
5099 arg2
= save_expr (arg2
);
5100 arg2
= build_vector_from_val (vtype
, arg2
);
5102 arg3
= cp_convert (stype
, arg3
, complain
);
5103 arg3
= save_expr (arg3
);
5104 arg3
= build_vector_from_val (vtype
, arg3
);
5108 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5110 enum stv_conv convert_flag
=
5111 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5112 complain
& tf_error
);
5114 switch (convert_flag
)
5117 return error_mark_node
;
5120 arg2
= save_expr (arg2
);
5121 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5122 arg2
= build_vector_from_val (arg3_type
, arg2
);
5123 arg2_type
= TREE_TYPE (arg2
);
5128 arg3
= save_expr (arg3
);
5129 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5130 arg3
= build_vector_from_val (arg2_type
, arg3
);
5131 arg3_type
= TREE_TYPE (arg3
);
5139 if (!same_type_p (arg2_type
, arg3_type
)
5140 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5141 TYPE_VECTOR_SUBPARTS (arg2_type
))
5142 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5144 if (complain
& tf_error
)
5146 "incompatible vector types in conditional expression: "
5147 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5148 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5149 return error_mark_node
;
5152 if (!COMPARISON_CLASS_P (arg1
))
5154 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5155 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5157 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5162 The first expression is implicitly converted to bool (clause
5164 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5166 if (error_operand_p (arg1
))
5167 return error_mark_node
;
5171 If either the second or the third operand has type (possibly
5172 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5173 array-to-pointer (_conv.array_), and function-to-pointer
5174 (_conv.func_) standard conversions are performed on the second
5175 and third operands. */
5176 arg2_type
= unlowered_expr_type (arg2
);
5177 arg3_type
= unlowered_expr_type (arg3
);
5178 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5180 /* 'void' won't help in resolving an overloaded expression on the
5181 other side, so require it to resolve by itself. */
5182 if (arg2_type
== unknown_type_node
)
5184 arg2
= resolve_nondeduced_context_or_error (arg2
, complain
);
5185 arg2_type
= TREE_TYPE (arg2
);
5187 if (arg3_type
== unknown_type_node
)
5189 arg3
= resolve_nondeduced_context_or_error (arg3
, complain
);
5190 arg3_type
= TREE_TYPE (arg3
);
5195 One of the following shall hold:
5197 --The second or the third operand (but not both) is a
5198 throw-expression (_except.throw_); the result is of the type
5199 and value category of the other.
5201 --Both the second and the third operands have type void; the
5202 result is of type void and is a prvalue. */
5203 if (TREE_CODE (arg2
) == THROW_EXPR
5204 && TREE_CODE (arg3
) != THROW_EXPR
)
5206 result_type
= arg3_type
;
5207 is_glvalue
= glvalue_p (arg3
);
5209 else if (TREE_CODE (arg2
) != THROW_EXPR
5210 && TREE_CODE (arg3
) == THROW_EXPR
)
5212 result_type
= arg2_type
;
5213 is_glvalue
= glvalue_p (arg2
);
5215 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5217 result_type
= void_type_node
;
5222 if (complain
& tf_error
)
5224 if (VOID_TYPE_P (arg2_type
))
5225 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5226 "second operand to the conditional operator "
5227 "is of type %<void%>, but the third operand is "
5228 "neither a throw-expression nor of type %<void%>");
5230 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5231 "third operand to the conditional operator "
5232 "is of type %<void%>, but the second operand is "
5233 "neither a throw-expression nor of type %<void%>");
5235 return error_mark_node
;
5238 goto valid_operands
;
5242 Otherwise, if the second and third operand have different types,
5243 and either has (possibly cv-qualified) class type, or if both are
5244 glvalues of the same value category and the same type except for
5245 cv-qualification, an attempt is made to convert each of those operands
5246 to the type of the other. */
5247 else if (!same_type_p (arg2_type
, arg3_type
)
5248 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5249 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5251 && glvalue_p (arg2
) && glvalue_p (arg3
)
5252 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5256 bool converted
= false;
5258 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5259 p
= conversion_obstack_alloc (0);
5261 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5262 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5266 If both can be converted, or one can be converted but the
5267 conversion is ambiguous, the program is ill-formed. If
5268 neither can be converted, the operands are left unchanged and
5269 further checking is performed as described below. If exactly
5270 one conversion is possible, that conversion is applied to the
5271 chosen operand and the converted operand is used in place of
5272 the original operand for the remainder of this section. */
5273 if ((conv2
&& !conv2
->bad_p
5274 && conv3
&& !conv3
->bad_p
)
5275 || (conv2
&& conv2
->kind
== ck_ambig
)
5276 || (conv3
&& conv3
->kind
== ck_ambig
))
5278 if (complain
& tf_error
)
5280 error_at (loc
, "operands to %<?:%> have different types "
5282 arg2_type
, arg3_type
);
5283 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5284 inform (loc
, " and each type can be converted to the other");
5285 else if (conv2
&& conv2
->kind
== ck_ambig
)
5286 convert_like (conv2
, arg2
, complain
);
5288 convert_like (conv3
, arg3
, complain
);
5290 result
= error_mark_node
;
5292 else if (conv2
&& !conv2
->bad_p
)
5294 arg2
= convert_like (conv2
, arg2
, complain
);
5295 arg2
= convert_from_reference (arg2
);
5296 arg2_type
= TREE_TYPE (arg2
);
5297 /* Even if CONV2 is a valid conversion, the result of the
5298 conversion may be invalid. For example, if ARG3 has type
5299 "volatile X", and X does not have a copy constructor
5300 accepting a "volatile X&", then even if ARG2 can be
5301 converted to X, the conversion will fail. */
5302 if (error_operand_p (arg2
))
5303 result
= error_mark_node
;
5306 else if (conv3
&& !conv3
->bad_p
)
5308 arg3
= convert_like (conv3
, arg3
, complain
);
5309 arg3
= convert_from_reference (arg3
);
5310 arg3_type
= TREE_TYPE (arg3
);
5311 if (error_operand_p (arg3
))
5312 result
= error_mark_node
;
5316 /* Free all the conversions we allocated. */
5317 obstack_free (&conversion_obstack
, p
);
5322 /* If, after the conversion, both operands have class type,
5323 treat the cv-qualification of both operands as if it were the
5324 union of the cv-qualification of the operands.
5326 The standard is not clear about what to do in this
5327 circumstance. For example, if the first operand has type
5328 "const X" and the second operand has a user-defined
5329 conversion to "volatile X", what is the type of the second
5330 operand after this step? Making it be "const X" (matching
5331 the first operand) seems wrong, as that discards the
5332 qualification without actually performing a copy. Leaving it
5333 as "volatile X" seems wrong as that will result in the
5334 conditional expression failing altogether, even though,
5335 according to this step, the one operand could be converted to
5336 the type of the other. */
5338 && CLASS_TYPE_P (arg2_type
)
5339 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5340 arg2_type
= arg3_type
=
5341 cp_build_qualified_type (arg2_type
,
5342 cp_type_quals (arg2_type
)
5343 | cp_type_quals (arg3_type
));
5348 If the second and third operands are glvalues of the same value
5349 category and have the same type, the result is of that type and
5351 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5352 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5353 && same_type_p (arg2_type
, arg3_type
))
5355 result_type
= arg2_type
;
5356 arg2
= mark_lvalue_use (arg2
);
5357 arg3
= mark_lvalue_use (arg3
);
5358 goto valid_operands
;
5363 Otherwise, the result is an rvalue. If the second and third
5364 operand do not have the same type, and either has (possibly
5365 cv-qualified) class type, overload resolution is used to
5366 determine the conversions (if any) to be applied to the operands
5367 (_over.match.oper_, _over.built_). */
5369 if (!same_type_p (arg2_type
, arg3_type
)
5370 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5376 /* Rearrange the arguments so that add_builtin_candidate only has
5377 to know about two args. In build_builtin_candidate, the
5378 arguments are unscrambled. */
5382 add_builtin_candidates (&candidates
,
5385 ovl_op_identifier (false, COND_EXPR
),
5387 LOOKUP_NORMAL
, complain
);
5391 If the overload resolution fails, the program is
5393 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5396 if (complain
& tf_error
)
5397 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5398 arg2_type
, arg3_type
);
5399 return error_mark_node
;
5401 cand
= tourney (candidates
, complain
);
5404 if (complain
& tf_error
)
5406 auto_diagnostic_group d
;
5407 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5408 print_z_candidates (loc
, candidates
);
5410 return error_mark_node
;
5415 Otherwise, the conversions thus determined are applied, and
5416 the converted operands are used in place of the original
5417 operands for the remainder of this section. */
5418 conv
= cand
->convs
[0];
5419 arg1
= convert_like (conv
, arg1
, complain
);
5420 conv
= cand
->convs
[1];
5421 arg2
= convert_like (conv
, arg2
, complain
);
5422 arg2_type
= TREE_TYPE (arg2
);
5423 conv
= cand
->convs
[2];
5424 arg3
= convert_like (conv
, arg3
, complain
);
5425 arg3_type
= TREE_TYPE (arg3
);
5430 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5431 and function-to-pointer (_conv.func_) standard conversions are
5432 performed on the second and third operands.
5434 We need to force the lvalue-to-rvalue conversion here for class types,
5435 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5436 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5439 arg2
= force_rvalue (arg2
, complain
);
5440 if (!CLASS_TYPE_P (arg2_type
))
5441 arg2_type
= TREE_TYPE (arg2
);
5443 arg3
= force_rvalue (arg3
, complain
);
5444 if (!CLASS_TYPE_P (arg3_type
))
5445 arg3_type
= TREE_TYPE (arg3
);
5447 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5448 return error_mark_node
;
5452 After those conversions, one of the following shall hold:
5454 --The second and third operands have the same type; the result is of
5456 if (same_type_p (arg2_type
, arg3_type
))
5457 result_type
= arg2_type
;
5460 --The second and third operands have arithmetic or enumeration
5461 type; the usual arithmetic conversions are performed to bring
5462 them to a common type, and the result is of that type. */
5463 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5464 || UNSCOPED_ENUM_P (arg2_type
))
5465 && (ARITHMETIC_TYPE_P (arg3_type
)
5466 || UNSCOPED_ENUM_P (arg3_type
)))
5468 /* In this case, there is always a common type. */
5469 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5471 if (complain
& tf_warning
)
5472 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5473 "implicit conversion from %qH to %qI to "
5474 "match other result of conditional",
5477 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5478 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5480 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5481 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5482 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5483 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5484 && (DECL_CONTEXT (stripped_orig_arg2
)
5485 == DECL_CONTEXT (stripped_orig_arg3
)))
5486 /* Two enumerators from the same enumeration can have different
5487 types when the enumeration is still being defined. */;
5488 else if (complain
& tf_warning
)
5489 warning_at (loc
, OPT_Wenum_compare
, "enumerated mismatch "
5490 "in conditional expression: %qT vs %qT",
5491 arg2_type
, arg3_type
);
5493 else if (extra_warnings
5494 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5495 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5496 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5497 && !same_type_p (arg2_type
,
5498 type_promotes_to (arg3_type
)))))
5500 if (complain
& tf_warning
)
5501 warning_at (loc
, OPT_Wextra
, "enumerated and non-enumerated "
5502 "type in conditional expression");
5505 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5506 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5510 --The second and third operands have pointer type, or one has
5511 pointer type and the other is a null pointer constant; pointer
5512 conversions (_conv.ptr_) and qualification conversions
5513 (_conv.qual_) are performed to bring them to their composite
5514 pointer type (_expr.rel_). The result is of the composite
5517 --The second and third operands have pointer to member type, or
5518 one has pointer to member type and the other is a null pointer
5519 constant; pointer to member conversions (_conv.mem_) and
5520 qualification conversions (_conv.qual_) are performed to bring
5521 them to a common type, whose cv-qualification shall match the
5522 cv-qualification of either the second or the third operand.
5523 The result is of the common type. */
5524 else if ((null_ptr_cst_p (arg2
)
5525 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5526 || (null_ptr_cst_p (arg3
)
5527 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5528 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5529 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5530 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5532 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5533 arg3
, CPO_CONDITIONAL_EXPR
,
5535 if (result_type
== error_mark_node
)
5536 return error_mark_node
;
5537 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5538 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5543 if (complain
& tf_error
)
5544 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5545 arg2_type
, arg3_type
);
5546 return error_mark_node
;
5549 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5550 return error_mark_node
;
5553 if (processing_template_decl
&& is_glvalue
)
5555 /* Let lvalue_kind know this was a glvalue. */
5556 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5557 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5560 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5562 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5563 warn here, because the COND_EXPR will be turned into ARG2. */
5564 if (warn_duplicated_branches
5565 && (complain
& tf_warning
)
5566 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5567 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5568 "this condition has identical branches");
5570 /* We can't use result_type below, as fold might have returned a
5575 /* Expand both sides into the same slot, hopefully the target of
5576 the ?: expression. We used to check for TARGET_EXPRs here,
5577 but now we sometimes wrap them in NOP_EXPRs so the test would
5579 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5580 result
= get_target_expr_sfinae (result
, complain
);
5581 /* If this expression is an rvalue, but might be mistaken for an
5582 lvalue, we must add a NON_LVALUE_EXPR. */
5583 result
= rvalue (result
);
5586 result
= force_paren_expr (result
);
5591 /* Wrapper for above. */
5594 build_conditional_expr (const op_location_t
&loc
,
5595 tree arg1
, tree arg2
, tree arg3
,
5596 tsubst_flags_t complain
)
5599 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5600 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5601 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5605 /* OPERAND is an operand to an expression. Perform necessary steps
5606 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5610 prep_operand (tree operand
)
5614 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5615 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5616 /* Make sure the template type is instantiated now. */
5617 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5623 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5624 OVERLOAD) to the CANDIDATES, returning an updated list of
5625 CANDIDATES. The ARGS are the arguments provided to the call;
5626 if FIRST_ARG is non-null it is the implicit object argument,
5627 otherwise the first element of ARGS is used if needed. The
5628 EXPLICIT_TARGS are explicit template arguments provided.
5629 TEMPLATE_ONLY is true if only template functions should be
5630 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5631 add_function_candidate. */
5634 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5636 tree explicit_targs
, bool template_only
,
5637 tree conversion_path
, tree access_path
,
5639 struct z_candidate
**candidates
,
5640 tsubst_flags_t complain
)
5643 const vec
<tree
, va_gc
> *non_static_args
;
5644 bool check_list_ctor
= false;
5645 bool check_converting
= false;
5646 unification_kind_t strict
;
5651 /* Precalculate special handling of constructors and conversion ops. */
5652 tree fn
= OVL_FIRST (fns
);
5653 if (DECL_CONV_FN_P (fn
))
5655 check_list_ctor
= false;
5656 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5657 if (flags
& LOOKUP_NO_CONVERSION
)
5658 /* We're doing return_type(x). */
5659 strict
= DEDUCE_CONV
;
5661 /* We're doing x.operator return_type(). */
5662 strict
= DEDUCE_EXACT
;
5663 /* [over.match.funcs] For conversion functions, the function
5664 is considered to be a member of the class of the implicit
5665 object argument for the purpose of defining the type of
5666 the implicit object parameter. */
5667 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5671 if (DECL_CONSTRUCTOR_P (fn
))
5673 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5674 /* For list-initialization we consider explicit constructors
5675 and complain if one is chosen. */
5677 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5678 == LOOKUP_ONLYCONVERTING
);
5680 strict
= DEDUCE_CALL
;
5681 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5685 non_static_args
= args
;
5687 /* Delay creating the implicit this parameter until it is needed. */
5688 non_static_args
= NULL
;
5690 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5694 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5696 if (check_list_ctor
&& !is_list_ctor (fn
))
5699 tree fn_first_arg
= NULL_TREE
;
5700 const vec
<tree
, va_gc
> *fn_args
= args
;
5702 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5704 /* Figure out where the object arg comes from. If this
5705 function is a non-static member and we didn't get an
5706 implicit object argument, move it out of args. */
5707 if (first_arg
== NULL_TREE
)
5711 vec
<tree
, va_gc
> *tempvec
;
5712 vec_alloc (tempvec
, args
->length () - 1);
5713 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5714 tempvec
->quick_push (arg
);
5715 non_static_args
= tempvec
;
5716 first_arg
= (*args
)[0];
5719 fn_first_arg
= first_arg
;
5720 fn_args
= non_static_args
;
5723 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5724 add_template_candidate (candidates
,
5736 else if (!template_only
)
5737 add_function_candidate (candidates
,
5750 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5751 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5754 op_is_ordered (tree_code code
)
5760 return (flag_strong_eval_order
> 1 ? -1 : 0);
5764 return (flag_strong_eval_order
> 1 ? 1 : 0);
5767 // Not overloadable (yet).
5769 // Only one argument.
5776 return (flag_strong_eval_order
? 1 : 0);
5784 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5785 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5786 tsubst_flags_t complain
)
5788 struct z_candidate
*candidates
= 0, *cand
;
5789 vec
<tree
, va_gc
> *arglist
;
5791 tree result
= NULL_TREE
;
5792 bool result_valid_p
= false;
5793 enum tree_code code2
= NOP_EXPR
;
5794 enum tree_code code_orig_arg1
= ERROR_MARK
;
5795 enum tree_code code_orig_arg2
= ERROR_MARK
;
5801 if (error_operand_p (arg1
)
5802 || error_operand_p (arg2
)
5803 || error_operand_p (arg3
))
5804 return error_mark_node
;
5806 bool ismodop
= code
== MODIFY_EXPR
;
5809 code2
= TREE_CODE (arg3
);
5812 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5814 arg1
= prep_operand (arg1
);
5816 bool memonly
= false;
5821 case VEC_DELETE_EXPR
:
5823 /* Use build_op_new_call and build_op_delete_call instead. */
5827 /* Use build_op_call instead. */
5830 case TRUTH_ORIF_EXPR
:
5831 case TRUTH_ANDIF_EXPR
:
5832 case TRUTH_AND_EXPR
:
5834 /* These are saved for the sake of warn_logical_operator. */
5835 code_orig_arg1
= TREE_CODE (arg1
);
5836 code_orig_arg2
= TREE_CODE (arg2
);
5844 /* These are saved for the sake of maybe_warn_bool_compare. */
5845 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5846 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5849 /* =, ->, [], () must be non-static member functions. */
5851 if (code2
!= NOP_EXPR
)
5863 arg2
= prep_operand (arg2
);
5864 arg3
= prep_operand (arg3
);
5866 if (code
== COND_EXPR
)
5867 /* Use build_conditional_expr instead. */
5869 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5870 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5873 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5874 arg2
= integer_zero_node
;
5876 vec_alloc (arglist
, 3);
5877 arglist
->quick_push (arg1
);
5878 if (arg2
!= NULL_TREE
)
5879 arglist
->quick_push (arg2
);
5880 if (arg3
!= NULL_TREE
)
5881 arglist
->quick_push (arg3
);
5883 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5884 p
= conversion_obstack_alloc (0);
5886 /* Add namespace-scope operators to the list of functions to
5890 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5891 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5892 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5893 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5894 flags
, &candidates
, complain
);
5899 args
[2] = NULL_TREE
;
5901 /* Add class-member operators to the candidate set. */
5902 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5906 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5907 if (fns
== error_mark_node
)
5909 result
= error_mark_node
;
5910 goto user_defined_result_ready
;
5913 add_candidates (BASELINK_FUNCTIONS (fns
),
5914 NULL_TREE
, arglist
, NULL_TREE
,
5916 BASELINK_BINFO (fns
),
5917 BASELINK_ACCESS_BINFO (fns
),
5918 flags
, &candidates
, complain
);
5920 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5921 only non-member functions that have type T1 or reference to
5922 cv-qualified-opt T1 for the first argument, if the first argument
5923 has an enumeration type, or T2 or reference to cv-qualified-opt
5924 T2 for the second argument, if the second argument has an
5925 enumeration type. Filter out those that don't match. */
5926 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5928 struct z_candidate
**candp
, **next
;
5930 for (candp
= &candidates
; *candp
; candp
= next
)
5932 tree parmlist
, parmtype
;
5933 int i
, nargs
= (arg2
? 2 : 1);
5938 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5940 for (i
= 0; i
< nargs
; ++i
)
5942 parmtype
= TREE_VALUE (parmlist
);
5944 if (TYPE_REF_P (parmtype
))
5945 parmtype
= TREE_TYPE (parmtype
);
5946 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5947 && (same_type_ignoring_top_level_qualifiers_p
5948 (TREE_TYPE (args
[i
]), parmtype
)))
5951 parmlist
= TREE_CHAIN (parmlist
);
5954 /* No argument has an appropriate type, so remove this
5955 candidate function from the list. */
5958 *candp
= cand
->next
;
5964 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5971 /* For these, the built-in candidates set is empty
5972 [over.match.oper]/3. We don't want non-strict matches
5973 because exact matches are always possible with built-in
5974 operators. The built-in candidate set for COMPONENT_REF
5975 would be empty too, but since there are no such built-in
5976 operators, we accept non-strict matches for them. */
5985 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5990 case POSTINCREMENT_EXPR
:
5991 case POSTDECREMENT_EXPR
:
5992 /* Don't try anything fancy if we're not allowed to produce
5994 if (!(complain
& tf_error
))
5995 return error_mark_node
;
5997 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5998 distinguish between prefix and postfix ++ and
5999 operator++() was used for both, so we allow this with
6003 const char *msg
= (flag_permissive
)
6004 ? G_("no %<%D(int)%> declared for postfix %qs,"
6005 " trying prefix operator instead")
6006 : G_("no %<%D(int)%> declared for postfix %qs");
6007 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
6010 if (!flag_permissive
)
6011 return error_mark_node
;
6013 if (code
== POSTINCREMENT_EXPR
)
6014 code
= PREINCREMENT_EXPR
;
6016 code
= PREDECREMENT_EXPR
;
6017 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
6018 NULL_TREE
, overload
, complain
);
6021 /* The caller will deal with these. */
6026 result_valid_p
= true;
6030 if (complain
& tf_error
)
6032 /* If one of the arguments of the operator represents
6033 an invalid use of member function pointer, try to report
6034 a meaningful error ... */
6035 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
6036 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
6037 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
6038 /* We displayed the error message. */;
6041 /* ... Otherwise, report the more generic
6042 "no matching operator found" error */
6043 auto_diagnostic_group d
;
6044 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
6045 print_z_candidates (loc
, candidates
);
6048 result
= error_mark_node
;
6054 cand
= tourney (candidates
, complain
);
6057 if (complain
& tf_error
)
6059 auto_diagnostic_group d
;
6060 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
6061 print_z_candidates (loc
, candidates
);
6063 result
= error_mark_node
;
6065 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
6068 *overload
= cand
->fn
;
6070 if (resolve_args (arglist
, complain
) == NULL
)
6071 result
= error_mark_node
;
6073 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6075 if (trivial_fn_p (cand
->fn
))
6076 /* There won't be a CALL_EXPR. */;
6077 else if (result
&& result
!= error_mark_node
)
6079 tree call
= extract_call_expr (result
);
6080 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
6082 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
6083 /* This prevents build_new_function_call from discarding this
6084 function during instantiation of the enclosing template. */
6085 KOENIG_LOOKUP_P (call
) = 1;
6087 /* Specify evaluation order as per P0145R2. */
6088 CALL_EXPR_ORDERED_ARGS (call
) = false;
6089 switch (op_is_ordered (code
))
6092 CALL_EXPR_REVERSE_ARGS (call
) = true;
6096 CALL_EXPR_ORDERED_ARGS (call
) = true;
6106 /* Give any warnings we noticed during overload resolution. */
6107 if (cand
->warnings
&& (complain
& tf_warning
))
6109 struct candidate_warning
*w
;
6110 for (w
= cand
->warnings
; w
; w
= w
->next
)
6111 joust (cand
, w
->loser
, 1, complain
);
6114 /* Check for comparison of different enum types. */
6123 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
6124 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
6125 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
6126 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
6127 && (complain
& tf_warning
))
6129 warning (OPT_Wenum_compare
,
6130 "comparison between %q#T and %q#T",
6131 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
6138 /* We need to strip any leading REF_BIND so that bitfields
6139 don't cause errors. This should not remove any important
6140 conversions, because builtins don't apply to class
6141 objects directly. */
6142 conv
= cand
->convs
[0];
6143 if (conv
->kind
== ck_ref_bind
)
6144 conv
= next_conversion (conv
);
6145 arg1
= convert_like (conv
, arg1
, complain
);
6149 conv
= cand
->convs
[1];
6150 if (conv
->kind
== ck_ref_bind
)
6151 conv
= next_conversion (conv
);
6153 arg2
= decay_conversion (arg2
, complain
);
6155 /* We need to call warn_logical_operator before
6156 converting arg2 to a boolean_type, but after
6157 decaying an enumerator to its value. */
6158 if (complain
& tf_warning
)
6159 warn_logical_operator (loc
, code
, boolean_type_node
,
6160 code_orig_arg1
, arg1
,
6161 code_orig_arg2
, arg2
);
6163 arg2
= convert_like (conv
, arg2
, complain
);
6167 conv
= cand
->convs
[2];
6168 if (conv
->kind
== ck_ref_bind
)
6169 conv
= next_conversion (conv
);
6170 convert_like (conv
, arg3
, complain
);
6176 user_defined_result_ready
:
6178 /* Free all the conversions we allocated. */
6179 obstack_free (&conversion_obstack
, p
);
6181 if (result
|| result_valid_p
)
6188 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6191 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6193 case TRUTH_ANDIF_EXPR
:
6194 case TRUTH_ORIF_EXPR
:
6195 case TRUTH_AND_EXPR
:
6197 if (complain
& tf_warning
)
6198 warn_logical_operator (loc
, code
, boolean_type_node
,
6199 code_orig_arg1
, arg1
,
6200 code_orig_arg2
, arg2
);
6208 if ((complain
& tf_warning
)
6209 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6210 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6211 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6212 if (complain
& tf_warning
&& warn_tautological_compare
)
6213 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6218 case TRUNC_DIV_EXPR
:
6223 case TRUNC_MOD_EXPR
:
6227 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6229 case UNARY_PLUS_EXPR
:
6232 case TRUTH_NOT_EXPR
:
6233 case PREINCREMENT_EXPR
:
6234 case POSTINCREMENT_EXPR
:
6235 case PREDECREMENT_EXPR
:
6236 case POSTDECREMENT_EXPR
:
6240 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6243 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6246 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6250 /* The caller will deal with these. */
6262 /* Wrapper for above. */
6265 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6266 tree arg1
, tree arg2
, tree arg3
,
6267 tree
*overload
, tsubst_flags_t complain
)
6270 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6271 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6272 overload
, complain
);
6273 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6277 /* CALL was returned by some call-building function; extract the actual
6278 CALL_EXPR from any bits that have been tacked on, e.g. by
6279 convert_from_reference. */
6282 extract_call_expr (tree call
)
6284 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6285 call
= TREE_OPERAND (call
, 1);
6286 if (REFERENCE_REF_P (call
))
6287 call
= TREE_OPERAND (call
, 0);
6288 if (TREE_CODE (call
) == TARGET_EXPR
)
6289 call
= TARGET_EXPR_INITIAL (call
);
6290 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6291 || TREE_CODE (call
) == AGGR_INIT_EXPR
6292 || call
== error_mark_node
);
6296 /* Returns true if FN has two parameters, of which the second has type
6300 second_parm_is_size_t (tree fn
)
6302 tree t
= FUNCTION_ARG_CHAIN (fn
);
6303 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6306 if (t
== void_list_node
)
6311 /* True if T, an allocation function, has std::align_val_t as its second
6315 aligned_allocation_fn_p (tree t
)
6317 if (!aligned_new_threshold
)
6320 tree a
= FUNCTION_ARG_CHAIN (t
);
6321 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6324 /* True if T is std::destroying_delete_t. */
6327 std_destroying_delete_t_p (tree t
)
6329 return (TYPE_CONTEXT (t
) == std_node
6330 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6333 /* A deallocation function with at least two parameters whose second parameter
6334 type is of type std::destroying_delete_t is a destroying operator delete. A
6335 destroying operator delete shall be a class member function named operator
6336 delete. [ Note: Array deletion cannot use a destroying operator
6337 delete. --end note ] */
6340 destroying_delete_p (tree t
)
6342 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6343 if (!a
|| !TREE_CHAIN (a
))
6345 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6346 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6356 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6357 function (3.7.4.2 [basic.stc.dynamic.deallocation]). If so, and DI is
6358 non-null, also set *DI. */
6361 usual_deallocation_fn_p (tree t
, dealloc_info
*di
)
6363 if (di
) *di
= dealloc_info();
6365 /* A template instance is never a usual deallocation function,
6366 regardless of its signature. */
6367 if (TREE_CODE (t
) == TEMPLATE_DECL
6368 || primary_template_specialization_p (t
))
6371 /* A usual deallocation function is a deallocation function whose parameters
6373 - optionally, a parameter of type std::destroying_delete_t, then
6374 - optionally, a parameter of type std::size_t, then
6375 - optionally, a parameter of type std::align_val_t. */
6376 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6377 tree chain
= FUNCTION_ARG_CHAIN (t
);
6378 if (chain
&& destroying_delete_p (t
))
6380 if (di
) di
->destroying
= TREE_VALUE (chain
);
6381 chain
= TREE_CHAIN (chain
);
6384 && (!global
|| flag_sized_deallocation
)
6385 && same_type_p (TREE_VALUE (chain
), size_type_node
))
6387 if (di
) di
->sized
= true;
6388 chain
= TREE_CHAIN (chain
);
6390 if (chain
&& aligned_new_threshold
6391 && same_type_p (TREE_VALUE (chain
), align_type_node
))
6393 if (di
) di
->aligned
= true;
6394 chain
= TREE_CHAIN (chain
);
6396 return (chain
== void_list_node
);
6399 /* Just return whether FN is a usual deallocation function. */
6402 usual_deallocation_fn_p (tree fn
)
6404 return usual_deallocation_fn_p (fn
, NULL
);
6407 /* Build a call to operator delete. This has to be handled very specially,
6408 because the restrictions on what signatures match are different from all
6409 other call instances. For a normal delete, only a delete taking (void *)
6410 or (void *, size_t) is accepted. For a placement delete, only an exact
6411 match with the placement new is accepted.
6413 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6414 ADDR is the pointer to be deleted.
6415 SIZE is the size of the memory block to be deleted.
6416 GLOBAL_P is true if the delete-expression should not consider
6417 class-specific delete operators.
6418 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6420 If this call to "operator delete" is being generated as part to
6421 deallocate memory allocated via a new-expression (as per [expr.new]
6422 which requires that if the initialization throws an exception then
6423 we call a deallocation function), then ALLOC_FN is the allocation
6427 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6428 bool global_p
, tree placement
,
6429 tree alloc_fn
, tsubst_flags_t complain
)
6431 tree fn
= NULL_TREE
;
6432 tree fns
, fnname
, type
, t
;
6433 dealloc_info di_fn
= { };
6435 if (addr
== error_mark_node
)
6436 return error_mark_node
;
6438 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6440 fnname
= ovl_op_identifier (false, code
);
6442 if (CLASS_TYPE_P (type
)
6443 && COMPLETE_TYPE_P (complete_type (type
))
6447 If the result of the lookup is ambiguous or inaccessible, or if
6448 the lookup selects a placement deallocation function, the
6449 program is ill-formed.
6451 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6453 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6454 if (fns
== error_mark_node
)
6455 return error_mark_node
;
6460 if (fns
== NULL_TREE
)
6461 fns
= lookup_name_nonclass (fnname
);
6463 /* Strip const and volatile from addr. */
6465 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6469 /* "A declaration of a placement deallocation function matches the
6470 declaration of a placement allocation function if it has the same
6471 number of parameters and, after parameter transformations (8.3.5),
6472 all parameter types except the first are identical."
6474 So we build up the function type we want and ask instantiate_type
6475 to get it for us. */
6476 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6477 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6478 t
= build_function_type (void_type_node
, t
);
6480 fn
= instantiate_type (t
, fns
, tf_none
);
6481 if (fn
== error_mark_node
)
6484 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6486 /* "If the lookup finds the two-parameter form of a usual deallocation
6487 function (3.7.4.2) and that function, considered as a placement
6488 deallocation function, would have been selected as a match for the
6489 allocation function, the program is ill-formed." */
6490 if (second_parm_is_size_t (fn
))
6492 const char *const msg1
6493 = G_("exception cleanup for this placement new selects "
6494 "non-placement %<operator delete%>");
6495 const char *const msg2
6496 = G_("%qD is a usual (non-placement) deallocation "
6497 "function in C++14 (or with %<-fsized-deallocation%>)");
6499 /* But if the class has an operator delete (void *), then that is
6500 the usual deallocation function, so we shouldn't complain
6501 about using the operator delete (void *, size_t). */
6502 if (DECL_CLASS_SCOPE_P (fn
))
6503 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6507 if (usual_deallocation_fn_p (elt
)
6508 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6511 /* Before C++14 a two-parameter global deallocation function is
6512 always a placement deallocation function, but warn if
6514 else if (!flag_sized_deallocation
)
6516 if (complain
& tf_warning
)
6518 auto_diagnostic_group d
;
6519 if (warning (OPT_Wc__14_compat
, msg1
))
6520 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6525 if (complain
& tf_warning_or_error
)
6527 auto_diagnostic_group d
;
6528 if (permerror (input_location
, msg1
))
6530 /* Only mention C++14 for namespace-scope delete. */
6531 if (DECL_NAMESPACE_SCOPE_P (fn
))
6532 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6534 inform (DECL_SOURCE_LOCATION (fn
),
6535 "%qD is a usual (non-placement) deallocation "
6540 return error_mark_node
;
6545 /* "Any non-placement deallocation function matches a non-placement
6546 allocation function. If the lookup finds a single matching
6547 deallocation function, that function will be called; otherwise, no
6548 deallocation function will be called." */
6549 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6552 dealloc_info di_elt
;
6553 if (usual_deallocation_fn_p (elt
, &di_elt
))
6562 /* -- If any of the deallocation functions is a destroying
6563 operator delete, all deallocation functions that are not
6564 destroying operator deletes are eliminated from further
6566 if (di_elt
.destroying
!= di_fn
.destroying
)
6568 if (di_elt
.destroying
)
6576 /* -- If the type has new-extended alignment, a function with a
6577 parameter of type std::align_val_t is preferred; otherwise a
6578 function without such a parameter is preferred. If exactly one
6579 preferred function is found, that function is selected and the
6580 selection process terminates. If more than one preferred
6581 function is found, all non-preferred functions are eliminated
6582 from further consideration. */
6583 if (aligned_new_threshold
)
6585 bool want_align
= type_has_new_extended_alignment (type
);
6586 if (di_elt
.aligned
!= di_fn
.aligned
)
6588 if (want_align
== di_elt
.aligned
)
6597 /* -- If the deallocation functions have class scope, the one
6598 without a parameter of type std::size_t is selected. */
6600 if (DECL_CLASS_SCOPE_P (fn
))
6603 /* -- If the type is complete and if, for the second alternative
6604 (delete array) only, the operand is a pointer to a class type
6605 with a non-trivial destructor or a (possibly multi-dimensional)
6606 array thereof, the function with a parameter of type std::size_t
6609 -- Otherwise, it is unspecified whether a deallocation function
6610 with a parameter of type std::size_t is selected. */
6613 want_size
= COMPLETE_TYPE_P (type
);
6614 if (code
== VEC_DELETE_EXPR
6615 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6616 /* We need a cookie to determine the array size. */
6619 gcc_assert (di_fn
.sized
!= di_elt
.sized
);
6620 if (want_size
== di_elt
.sized
)
6628 /* If we have a matching function, call it. */
6631 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6633 /* If the FN is a member function, make sure that it is
6635 if (BASELINK_P (fns
))
6636 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6639 /* Core issue 901: It's ok to new a type with deleted delete. */
6640 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6645 /* The placement args might not be suitable for overload
6646 resolution at this point, so build the call directly. */
6647 int nargs
= call_expr_nargs (placement
);
6648 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6651 for (i
= 1; i
< nargs
; i
++)
6652 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6653 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6654 return error_mark_node
;
6655 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6659 tree destroying
= di_fn
.destroying
;
6662 /* Strip const and volatile from addr but retain the type of the
6664 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6665 rtype
= cv_unqualified (rtype
);
6666 rtype
= TYPE_POINTER_TO (rtype
);
6667 addr
= cp_convert (rtype
, oaddr
, complain
);
6668 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6674 args
->quick_push (addr
);
6676 args
->quick_push (destroying
);
6678 args
->quick_push (size
);
6681 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6682 args
->quick_push (al
);
6684 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6691 If no unambiguous matching deallocation function can be found,
6692 propagating the exception does not cause the object's memory to
6696 if ((complain
& tf_warning
)
6698 warning (0, "no corresponding deallocation function for %qD",
6703 if (complain
& tf_error
)
6704 error ("no suitable %<operator %s%> for %qT",
6705 OVL_OP_INFO (false, code
)->name
, type
);
6706 return error_mark_node
;
6709 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6712 If ISSUE_ERROR is true, then issue an error about the
6713 access, followed by a note showing the declaration.
6714 Otherwise, just show the note. */
6717 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6719 if (TREE_PRIVATE (decl
))
6722 error ("%q#D is private within this context", diag_decl
);
6723 inform (DECL_SOURCE_LOCATION (diag_decl
),
6724 "declared private here");
6726 else if (TREE_PROTECTED (decl
))
6729 error ("%q#D is protected within this context", diag_decl
);
6730 inform (DECL_SOURCE_LOCATION (diag_decl
),
6731 "declared protected here");
6736 error ("%q#D is inaccessible within this context", diag_decl
);
6737 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6741 /* If the current scope isn't allowed to access DECL along
6742 BASETYPE_PATH, give an error. The most derived class in
6743 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6744 the declaration to use in the error diagnostic. */
6747 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6748 tsubst_flags_t complain
, access_failure_info
*afi
)
6750 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6752 if (flag_new_inheriting_ctors
6753 && DECL_INHERITED_CTOR (decl
))
6755 /* 7.3.3/18: The additional constructors are accessible if they would be
6756 accessible when used to construct an object of the corresponding base
6758 decl
= strip_inheriting_ctors (decl
);
6759 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6760 ba_any
, NULL
, complain
);
6763 if (!accessible_p (basetype_path
, decl
, true))
6765 if (flag_new_inheriting_ctors
)
6766 diag_decl
= strip_inheriting_ctors (diag_decl
);
6767 if (complain
& tf_error
)
6768 complain_about_access (decl
, diag_decl
, true);
6770 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6777 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6778 bitwise or of LOOKUP_* values. If any errors are warnings are
6779 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6780 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6784 build_temp (tree expr
, tree type
, int flags
,
6785 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6789 *diagnostic_kind
= DK_UNSPECIFIED
;
6791 /* If the source is a packed field, calling the copy constructor will require
6792 binding the field to the reference parameter to the copy constructor, and
6793 we'll end up with an infinite loop. If we can use a bitwise copy, then
6795 if ((lvalue_kind (expr
) & clk_packed
)
6796 && CLASS_TYPE_P (TREE_TYPE (expr
))
6797 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6798 return get_target_expr_sfinae (expr
, complain
);
6800 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6801 releasing_vec
args (make_tree_vector_single (expr
));
6802 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6803 &args
, type
, flags
, complain
);
6804 if (warningcount
+ werrorcount
> savew
)
6805 *diagnostic_kind
= DK_WARNING
;
6806 else if (errorcount
> savee
)
6807 *diagnostic_kind
= DK_ERROR
;
6811 /* Get any location for EXPR, falling back to input_location.
6813 If the result is in a system header and is the virtual location for
6814 a token coming from the expansion of a macro, unwind it to the
6815 location of the expansion point of the macro (e.g. to avoid the
6816 diagnostic being suppressed for expansions of NULL where "NULL" is
6817 in a system header). */
6820 get_location_for_expr_unwinding_for_system_header (tree expr
)
6822 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6823 loc
= expansion_point_location_if_in_system_header (loc
);
6827 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6828 Also handle a subset of zero as null warnings.
6829 EXPR is implicitly converted to type TOTYPE.
6830 FN and ARGNUM are used for diagnostics. */
6833 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6835 /* Issue warnings about peculiar, but valid, uses of NULL. */
6836 if (TREE_CODE (totype
) != BOOLEAN_TYPE
6837 && ARITHMETIC_TYPE_P (totype
)
6838 && null_node_p (expr
))
6840 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6843 auto_diagnostic_group d
;
6844 if (warning_at (loc
, OPT_Wconversion_null
,
6845 "passing NULL to non-pointer argument %P of %qD",
6847 inform (get_fndecl_argument_location (fn
, argnum
),
6851 warning_at (loc
, OPT_Wconversion_null
,
6852 "converting to non-pointer type %qT from NULL", totype
);
6855 /* Issue warnings if "false" is converted to a NULL pointer */
6856 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6857 && TYPE_PTR_P (totype
))
6859 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6862 auto_diagnostic_group d
;
6863 if (warning_at (loc
, OPT_Wconversion_null
,
6864 "converting %<false%> to pointer type for argument "
6865 "%P of %qD", argnum
, fn
))
6866 inform (get_fndecl_argument_location (fn
, argnum
),
6870 warning_at (loc
, OPT_Wconversion_null
,
6871 "converting %<false%> to pointer type %qT", totype
);
6873 /* Handle zero as null pointer warnings for cases other
6874 than EQ_EXPR and NE_EXPR */
6875 else if ((TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
))
6876 && null_ptr_cst_p (expr
))
6878 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6879 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6883 /* We gave a diagnostic during a conversion. If this was in the second
6884 standard conversion sequence of a user-defined conversion sequence, say
6885 which user-defined conversion. */
6888 maybe_print_user_conv_context (conversion
*convs
)
6890 if (convs
->user_conv_p
)
6891 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6892 if (t
->kind
== ck_user
)
6894 print_z_candidate (0, N_(" after user-defined conversion:"),
6900 /* Locate the parameter with the given index within FNDECL.
6901 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6902 Return the location of the FNDECL itself if there are problems. */
6905 get_fndecl_argument_location (tree fndecl
, int argnum
)
6907 /* The locations of implicitly-declared functions are likely to be
6908 more meaningful than those of their parameters. */
6909 if (DECL_ARTIFICIAL (fndecl
))
6910 return DECL_SOURCE_LOCATION (fndecl
);
6915 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6916 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6917 i
< argnum
&& param
;
6918 i
++, param
= TREE_CHAIN (param
))
6921 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6922 return the location of FNDECL. */
6924 return DECL_SOURCE_LOCATION (fndecl
);
6926 return DECL_SOURCE_LOCATION (param
);
6929 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6930 within its declaration (or the fndecl itself if something went
6934 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6937 inform (get_fndecl_argument_location (fn
, argnum
),
6938 " initializing argument %P of %qD", argnum
, fn
);
6941 /* Perform the conversions in CONVS on the expression EXPR. FN and
6942 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6943 indicates the `this' argument of a method. INNER is nonzero when
6944 being called to continue a conversion chain. It is negative when a
6945 reference binding will be applied, positive otherwise. If
6946 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6947 conversions will be emitted if appropriate. If C_CAST_P is true,
6948 this conversion is coming from a C-style cast; in that case,
6949 conversions to inaccessible bases are permitted. */
6952 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6953 bool issue_conversion_warnings
,
6954 bool c_cast_p
, tsubst_flags_t complain
)
6956 tree totype
= convs
->type
;
6957 diagnostic_t diag_kind
;
6959 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
6961 if (convs
->bad_p
&& !(complain
& tf_error
))
6962 return error_mark_node
;
6965 && convs
->kind
!= ck_user
6966 && convs
->kind
!= ck_list
6967 && convs
->kind
!= ck_ambig
6968 && (convs
->kind
!= ck_ref_bind
6969 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6970 && (convs
->kind
!= ck_rvalue
6971 || SCALAR_TYPE_P (totype
))
6972 && convs
->kind
!= ck_base
)
6974 bool complained
= false;
6975 conversion
*t
= convs
;
6977 /* Give a helpful error if this is bad because of excess braces. */
6978 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6979 && SCALAR_TYPE_P (totype
)
6980 && CONSTRUCTOR_NELTS (expr
) > 0
6981 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6983 complained
= permerror (loc
, "too many braces around initializer "
6985 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6986 && CONSTRUCTOR_NELTS (expr
) == 1)
6987 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6990 /* Give a helpful error if this is bad because a conversion to bool
6991 from std::nullptr_t requires direct-initialization. */
6992 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6993 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6994 complained
= permerror (loc
, "converting to %qH from %qI requires "
6995 "direct-initialization",
6996 totype
, TREE_TYPE (expr
));
6998 for (; t
; t
= next_conversion (t
))
7000 if (t
->kind
== ck_user
&& t
->cand
->reason
)
7002 auto_diagnostic_group d
;
7003 complained
= permerror (loc
, "invalid user-defined conversion "
7004 "from %qH to %qI", TREE_TYPE (expr
),
7007 print_z_candidate (loc
, N_("candidate is:"), t
->cand
);
7008 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7009 /*issue_conversion_warnings=*/false,
7012 if (convs
->kind
== ck_ref_bind
)
7013 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
7014 LOOKUP_NORMAL
, NULL_TREE
,
7017 expr
= cp_convert (totype
, expr
, complain
);
7019 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7022 else if (t
->kind
== ck_user
|| !t
->bad_p
)
7024 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7025 /*issue_conversion_warnings=*/false,
7030 else if (t
->kind
== ck_ambig
)
7031 return convert_like_real (t
, expr
, fn
, argnum
,
7032 /*issue_conversion_warnings=*/false,
7035 else if (t
->kind
== ck_identity
)
7040 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
7041 gcc_rich_location
richloc (loc
, &label
);
7042 complained
= permerror (&richloc
,
7043 "invalid conversion from %qH to %qI",
7044 TREE_TYPE (expr
), totype
);
7047 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7049 return cp_convert (totype
, expr
, complain
);
7052 if (issue_conversion_warnings
&& (complain
& tf_warning
))
7053 conversion_null_warnings (totype
, expr
, fn
, argnum
);
7055 switch (convs
->kind
)
7059 struct z_candidate
*cand
= convs
->cand
;
7062 /* We chose the surrogate function from add_conv_candidate, now we
7063 actually need to build the conversion. */
7064 cand
= build_user_type_conversion_1 (totype
, expr
,
7065 LOOKUP_NO_CONVERSION
, complain
);
7067 tree convfn
= cand
->fn
;
7069 /* When converting from an init list we consider explicit
7070 constructors, but actually trying to call one is an error. */
7071 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
7072 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
7073 /* Unless this is for direct-list-initialization. */
7074 && (!CONSTRUCTOR_IS_DIRECT_INIT (expr
) || convs
->need_temporary_p
)
7075 /* And in C++98 a default constructor can't be explicit. */
7076 && cxx_dialect
>= cxx11
)
7078 if (!(complain
& tf_error
))
7079 return error_mark_node
;
7080 location_t loc
= location_of (expr
);
7081 if (CONSTRUCTOR_NELTS (expr
) == 0
7082 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
7084 auto_diagnostic_group d
;
7085 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
7086 "would use explicit constructor %qD",
7088 inform (loc
, "in C++11 and above a default constructor "
7092 error ("converting to %qT from initializer list would use "
7093 "explicit constructor %qD", totype
, convfn
);
7096 /* If we're initializing from {}, it's value-initialization. */
7097 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7098 && CONSTRUCTOR_NELTS (expr
) == 0
7099 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
)
7100 && !processing_template_decl
)
7102 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
7103 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
7104 return error_mark_node
;
7105 expr
= build_value_init (totype
, complain
);
7106 expr
= get_target_expr_sfinae (expr
, complain
);
7107 if (expr
!= error_mark_node
)
7109 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7110 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
7115 /* We don't know here whether EXPR is being used as an lvalue or
7116 rvalue, but we know it's read. */
7117 mark_exp_read (expr
);
7119 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
7121 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
7124 /* If this is a constructor or a function returning an aggr type,
7125 we need to build up a TARGET_EXPR. */
7126 if (DECL_CONSTRUCTOR_P (convfn
))
7128 expr
= build_cplus_new (totype
, expr
, complain
);
7130 /* Remember that this was list-initialization. */
7131 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
7132 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7138 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
7140 int nelts
= CONSTRUCTOR_NELTS (expr
);
7142 expr
= build_value_init (totype
, complain
);
7143 else if (nelts
== 1)
7144 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7148 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7149 /*read_p=*/true, UNKNOWN_LOCATION
,
7150 /*reject_builtin=*/true);
7152 if (type_unknown_p (expr
))
7153 expr
= instantiate_type (totype
, expr
, complain
);
7154 if (expr
== null_node
7155 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7156 /* If __null has been converted to an integer type, we do not want to
7157 continue to warn about uses of EXPR as an integer, rather than as a
7159 expr
= build_int_cst (totype
, 0);
7162 /* We leave bad_p off ck_ambig because overload resolution considers
7163 it valid, it just fails when we try to perform it. So we need to
7164 check complain here, too. */
7165 if (complain
& tf_error
)
7167 /* Call build_user_type_conversion again for the error. */
7168 int flags
= (convs
->need_temporary_p
7169 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7170 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7171 gcc_assert (seen_error ());
7172 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7174 return error_mark_node
;
7178 /* Conversion to std::initializer_list<T>. */
7179 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7180 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7185 tree val
; unsigned ix
;
7187 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7189 /* Convert all the elements. */
7190 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7192 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
,
7193 argnum
, false, false, complain
);
7194 if (sub
== error_mark_node
)
7196 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7197 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7198 return error_mark_node
;
7199 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
),
7201 if (!TREE_CONSTANT (sub
))
7202 TREE_CONSTANT (new_ctor
) = false;
7204 /* Build up the array. */
7205 elttype
= cp_build_qualified_type
7206 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7207 array
= build_array_of_n_type (elttype
, len
);
7208 array
= finish_compound_literal (array
, new_ctor
, complain
);
7209 /* Take the address explicitly rather than via decay_conversion
7210 to avoid the error about taking the address of a temporary. */
7211 array
= cp_build_addr_expr (array
, complain
);
7214 array
= nullptr_node
;
7216 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7217 if (array
== error_mark_node
)
7218 return error_mark_node
;
7220 /* Build up the initializer_list object. Note: fail gracefully
7221 if the object cannot be completed because, for example, no
7222 definition is provided (c++/80956). */
7223 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7225 return error_mark_node
;
7226 tree field
= next_initializable_field (TYPE_FIELDS (totype
));
7227 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7228 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7229 field
= next_initializable_field (DECL_CHAIN (field
));
7230 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7231 tree new_ctor
= build_constructor (totype
, vec
);
7232 return get_target_expr_sfinae (new_ctor
, complain
);
7236 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7238 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7239 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7240 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7242 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7244 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7247 expr
= reshape_init (totype
, expr
, complain
);
7248 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7250 if (expr
!= error_mark_node
)
7251 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7258 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7259 convs
->kind
== ck_ref_bind
7260 ? issue_conversion_warnings
: false,
7261 c_cast_p
, complain
);
7262 if (expr
== error_mark_node
)
7263 return error_mark_node
;
7265 switch (convs
->kind
)
7268 expr
= decay_conversion (expr
, complain
);
7269 if (expr
== error_mark_node
)
7271 if (complain
& tf_error
)
7273 auto_diagnostic_group d
;
7274 maybe_print_user_conv_context (convs
);
7275 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7277 return error_mark_node
;
7280 if (! MAYBE_CLASS_TYPE_P (totype
))
7283 /* Don't introduce copies when passing arguments along to the inherited
7285 if (current_function_decl
7286 && flag_new_inheriting_ctors
7287 && DECL_INHERITED_CTOR (current_function_decl
))
7290 if (TREE_CODE (expr
) == TARGET_EXPR
7291 && TARGET_EXPR_LIST_INIT_P (expr
))
7292 /* Copy-list-initialization doesn't actually involve a copy. */
7297 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7299 /* We are going to bind a reference directly to a base-class
7300 subobject of EXPR. */
7301 /* Build an expression for `*((base*) &expr)'. */
7302 expr
= convert_to_base (expr
, totype
,
7303 !c_cast_p
, /*nonnull=*/true, complain
);
7307 /* Copy-initialization where the cv-unqualified version of the source
7308 type is the same class as, or a derived class of, the class of the
7309 destination [is treated as direct-initialization]. [dcl.init] */
7310 flags
= LOOKUP_NORMAL
;
7311 if (convs
->user_conv_p
)
7312 /* This conversion is being done in the context of a user-defined
7313 conversion (i.e. the second step of copy-initialization), so
7314 don't allow any more. */
7315 flags
|= LOOKUP_NO_CONVERSION
;
7317 flags
|= LOOKUP_ONLYCONVERTING
;
7318 if (convs
->rvaluedness_matches_p
)
7319 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7320 flags
|= LOOKUP_PREFER_RVALUE
;
7321 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7322 if (diag_kind
&& complain
)
7324 auto_diagnostic_group d
;
7325 maybe_print_user_conv_context (convs
);
7326 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7329 return build_cplus_new (totype
, expr
, complain
);
7333 tree ref_type
= totype
;
7335 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7337 tree extype
= TREE_TYPE (expr
);
7338 auto_diagnostic_group d
;
7339 if (TYPE_REF_IS_RVALUE (ref_type
)
7341 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7342 "lvalue of type %qI", totype
, extype
);
7343 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7344 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7345 error_at (loc
, "cannot bind non-const lvalue reference of "
7346 "type %qH to an rvalue of type %qI", totype
, extype
);
7347 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7348 error_at (loc
, "binding reference of type %qH to %qI "
7349 "discards qualifiers", totype
, extype
);
7352 maybe_print_user_conv_context (convs
);
7353 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7355 return error_mark_node
;
7358 /* If necessary, create a temporary.
7360 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7361 that need temporaries, even when their types are reference
7362 compatible with the type of reference being bound, so the
7363 upcoming call to cp_build_addr_expr doesn't fail. */
7364 if (convs
->need_temporary_p
7365 || TREE_CODE (expr
) == CONSTRUCTOR
7366 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7368 /* Otherwise, a temporary of type "cv1 T1" is created and
7369 initialized from the initializer expression using the rules
7370 for a non-reference copy-initialization (8.5). */
7372 tree type
= TREE_TYPE (ref_type
);
7373 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7375 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7376 (type
, next_conversion (convs
)->type
));
7377 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7378 && !TYPE_REF_IS_RVALUE (ref_type
))
7380 /* If the reference is volatile or non-const, we
7381 cannot create a temporary. */
7382 if (lvalue
& clk_bitfield
)
7383 error_at (loc
, "cannot bind bit-field %qE to %qT",
7385 else if (lvalue
& clk_packed
)
7386 error_at (loc
, "cannot bind packed field %qE to %qT",
7389 error_at (loc
, "cannot bind rvalue %qE to %qT",
7391 return error_mark_node
;
7393 /* If the source is a packed field, and we must use a copy
7394 constructor, then building the target expr will require
7395 binding the field to the reference parameter to the
7396 copy constructor, and we'll end up with an infinite
7397 loop. If we can use a bitwise copy, then we'll be
7399 if ((lvalue
& clk_packed
)
7400 && CLASS_TYPE_P (type
)
7401 && type_has_nontrivial_copy_init (type
))
7403 error_at (loc
, "cannot bind packed field %qE to %qT",
7405 return error_mark_node
;
7407 if (lvalue
& clk_bitfield
)
7409 expr
= convert_bitfield_to_declared_type (expr
);
7410 expr
= fold_convert (type
, expr
);
7412 expr
= build_target_expr_with_type (expr
, type
, complain
);
7415 /* Take the address of the thing to which we will bind the
7417 expr
= cp_build_addr_expr (expr
, complain
);
7418 if (expr
== error_mark_node
)
7419 return error_mark_node
;
7421 /* Convert it to a pointer to the type referred to by the
7422 reference. This will adjust the pointer if a derived to
7423 base conversion is being performed. */
7424 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7426 /* Convert the pointer to the desired reference type. */
7427 return build_nop (ref_type
, expr
);
7431 return decay_conversion (expr
, complain
);
7434 /* ??? Should the address of a transaction-safe pointer point to the TM
7435 clone, and this conversion look up the primary function? */
7436 return build_nop (totype
, expr
);
7439 /* Warn about deprecated conversion if appropriate. */
7440 if (complain
& tf_warning
)
7441 string_conv_p (totype
, expr
, 1);
7446 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7447 /*nonnull=*/false, complain
);
7448 return build_nop (totype
, expr
);
7451 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7452 c_cast_p
, complain
);
7458 if (convs
->check_narrowing
7459 && !check_narrowing (totype
, expr
, complain
,
7460 convs
->check_narrowing_const_only
))
7461 return error_mark_node
;
7463 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7464 if (issue_conversion_warnings
)
7465 expr
= cp_convert_and_check (totype
, expr
, complain
);
7467 expr
= cp_convert (totype
, expr
, complain
);
7472 /* ARG is being passed to a varargs function. Perform any conversions
7473 required. Return the converted value. */
7476 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7479 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
7483 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7484 standard conversions are performed. */
7485 arg
= decay_conversion (arg
, complain
);
7486 arg_type
= TREE_TYPE (arg
);
7489 If the argument has integral or enumeration type that is subject
7490 to the integral promotions (_conv.prom_), or a floating-point
7491 type that is subject to the floating-point promotion
7492 (_conv.fpprom_), the value of the argument is converted to the
7493 promoted type before the call. */
7494 if (TREE_CODE (arg_type
) == REAL_TYPE
7495 && (TYPE_PRECISION (arg_type
)
7496 < TYPE_PRECISION (double_type_node
))
7497 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7499 if ((complain
& tf_warning
)
7500 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7501 warning_at (loc
, OPT_Wdouble_promotion
,
7502 "implicit conversion from %qH to %qI when passing "
7503 "argument to function",
7504 arg_type
, double_type_node
);
7505 arg
= convert_to_real_nofold (double_type_node
, arg
);
7507 else if (NULLPTR_TYPE_P (arg_type
))
7508 arg
= null_pointer_node
;
7509 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7511 if (SCOPED_ENUM_P (arg_type
))
7513 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7515 prom
= cp_perform_integral_promotions (prom
, complain
);
7516 if (abi_version_crosses (6)
7517 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7518 && (complain
& tf_warning
))
7519 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through %<...%>"
7520 "as %qT before %<-fabi-version=6%>, %qT after",
7522 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7523 if (!abi_version_at_least (6))
7527 arg
= cp_perform_integral_promotions (arg
, complain
);
7530 arg
= require_complete_type_sfinae (arg
, complain
);
7531 arg_type
= TREE_TYPE (arg
);
7533 if (arg
!= error_mark_node
7534 /* In a template (or ill-formed code), we can have an incomplete type
7535 even after require_complete_type_sfinae, in which case we don't know
7536 whether it has trivial copy or not. */
7537 && COMPLETE_TYPE_P (arg_type
)
7538 && !cp_unevaluated_operand
)
7540 /* [expr.call] 5.2.2/7:
7541 Passing a potentially-evaluated argument of class type (Clause 9)
7542 with a non-trivial copy constructor or a non-trivial destructor
7543 with no corresponding parameter is conditionally-supported, with
7544 implementation-defined semantics.
7546 We support it as pass-by-invisible-reference, just like a normal
7549 If the call appears in the context of a sizeof expression,
7550 it is not potentially-evaluated. */
7551 if (type_has_nontrivial_copy_init (arg_type
)
7552 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7554 arg
= force_rvalue (arg
, complain
);
7555 if (complain
& tf_warning
)
7556 warning (OPT_Wconditionally_supported
,
7557 "passing objects of non-trivially-copyable "
7558 "type %q#T through %<...%> is conditionally supported",
7560 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7562 /* Build up a real lvalue-to-rvalue conversion in case the
7563 copy constructor is trivial but not callable. */
7564 else if (CLASS_TYPE_P (arg_type
))
7565 force_rvalue (arg
, complain
);
7572 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7575 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7577 if (processing_template_decl
)
7579 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7580 SET_EXPR_LOCATION (r
, loc
);
7584 type
= complete_type_or_else (type
, NULL_TREE
);
7586 if (expr
== error_mark_node
|| !type
)
7587 return error_mark_node
;
7589 expr
= mark_lvalue_use (expr
);
7591 if (TYPE_REF_P (type
))
7593 error ("cannot receive reference type %qT through %<...%>", type
);
7594 return error_mark_node
;
7597 if (type_has_nontrivial_copy_init (type
)
7598 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7600 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7601 it as pass by invisible reference. */
7602 warning_at (loc
, OPT_Wconditionally_supported
,
7603 "receiving objects of non-trivially-copyable type %q#T "
7604 "through %<...%> is conditionally-supported", type
);
7606 tree ref
= cp_build_reference_type (type
, false);
7607 expr
= build_va_arg (loc
, expr
, ref
);
7608 return convert_from_reference (expr
);
7611 tree ret
= build_va_arg (loc
, expr
, type
);
7612 if (CLASS_TYPE_P (type
))
7613 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7614 know how to handle it. */
7615 ret
= get_target_expr (ret
);
7619 /* TYPE has been given to va_arg. Apply the default conversions which
7620 would have happened when passed via ellipsis. Return the promoted
7621 type, or the passed type if there is no change. */
7624 cxx_type_promotes_to (tree type
)
7628 /* Perform the array-to-pointer and function-to-pointer
7630 type
= type_decays_to (type
);
7632 promote
= type_promotes_to (type
);
7633 if (same_type_p (type
, promote
))
7639 /* ARG is a default argument expression being passed to a parameter of
7640 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7641 zero-based argument number. Do any required conversions. Return
7642 the converted value. */
7644 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7646 push_defarg_context (tree fn
)
7647 { vec_safe_push (default_arg_context
, fn
); }
7650 pop_defarg_context (void)
7651 { default_arg_context
->pop (); }
7654 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7655 tsubst_flags_t complain
)
7660 /* See through clones. */
7661 fn
= DECL_ORIGIN (fn
);
7662 /* And inheriting ctors. */
7663 if (flag_new_inheriting_ctors
)
7664 fn
= strip_inheriting_ctors (fn
);
7666 /* Detect recursion. */
7667 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7670 if (complain
& tf_error
)
7671 error ("recursive evaluation of default argument for %q#D", fn
);
7672 return error_mark_node
;
7675 /* If the ARG is an unparsed default argument expression, the
7676 conversion cannot be performed. */
7677 if (TREE_CODE (arg
) == DEFERRED_PARSE
)
7679 if (complain
& tf_error
)
7680 error ("call to %qD uses the default argument for parameter %P, which "
7681 "is not yet defined", fn
, parmnum
);
7682 return error_mark_node
;
7685 push_defarg_context (fn
);
7687 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7688 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7694 The names in the expression are bound, and the semantic
7695 constraints are checked, at the point where the default
7696 expressions appears.
7698 we must not perform access checks here. */
7699 push_deferring_access_checks (dk_no_check
);
7700 /* We must make a copy of ARG, in case subsequent processing
7701 alters any part of it. */
7702 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7704 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7705 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7707 arg
= convert_for_arg_passing (type
, arg
, complain
);
7708 pop_deferring_access_checks();
7710 pop_defarg_context ();
7715 /* Returns the type which will really be used for passing an argument of
7719 type_passed_as (tree type
)
7721 /* Pass classes with copy ctors by invisible reference. */
7722 if (TREE_ADDRESSABLE (type
))
7724 type
= build_reference_type (type
);
7725 /* There are no other pointers to this temporary. */
7726 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7728 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7729 && INTEGRAL_TYPE_P (type
)
7730 && COMPLETE_TYPE_P (type
)
7731 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7732 type
= integer_type_node
;
7737 /* Actually perform the appropriate conversion. */
7740 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7744 /* If VAL is a bitfield, then -- since it has already been converted
7745 to TYPE -- it cannot have a precision greater than TYPE.
7747 If it has a smaller precision, we must widen it here. For
7748 example, passing "int f:3;" to a function expecting an "int" will
7749 not result in any conversion before this point.
7751 If the precision is the same we must not risk widening. For
7752 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7753 often have type "int", even though the C++ type for the field is
7754 "long long". If the value is being passed to a function
7755 expecting an "int", then no conversions will be required. But,
7756 if we call convert_bitfield_to_declared_type, the bitfield will
7757 be converted to "long long". */
7758 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7760 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7761 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7763 if (val
== error_mark_node
)
7765 /* Pass classes with copy ctors by invisible reference. */
7766 else if (TREE_ADDRESSABLE (type
))
7767 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7768 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7769 && INTEGRAL_TYPE_P (type
)
7770 && COMPLETE_TYPE_P (type
)
7771 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7772 val
= cp_perform_integral_promotions (val
, complain
);
7773 if (complain
& tf_warning
)
7775 if (warn_suggest_attribute_format
)
7777 tree rhstype
= TREE_TYPE (val
);
7778 const enum tree_code coder
= TREE_CODE (rhstype
);
7779 const enum tree_code codel
= TREE_CODE (type
);
7780 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7782 && check_missing_format_attribute (type
, rhstype
))
7783 warning (OPT_Wsuggest_attribute_format
,
7784 "argument of function call might be a candidate "
7785 "for a format attribute");
7787 maybe_warn_parm_abi (type
, cp_expr_loc_or_loc (val
, input_location
));
7790 if (complain
& tf_warning
)
7791 warn_for_address_or_pointer_of_packed_member (type
, val
);
7796 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7797 which just decay_conversion or no conversions at all should be done.
7798 This is true for some builtins which don't act like normal functions.
7799 Return 2 if no conversions at all should be done, 1 if just
7800 decay_conversion. Return 3 for special treatment of the 3rd argument
7801 for __builtin_*_overflow_p. */
7804 magic_varargs_p (tree fn
)
7806 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7807 switch (DECL_FUNCTION_CODE (fn
))
7809 case BUILT_IN_CLASSIFY_TYPE
:
7810 case BUILT_IN_CONSTANT_P
:
7811 case BUILT_IN_NEXT_ARG
:
7812 case BUILT_IN_VA_START
:
7815 case BUILT_IN_ADD_OVERFLOW_P
:
7816 case BUILT_IN_SUB_OVERFLOW_P
:
7817 case BUILT_IN_MUL_OVERFLOW_P
:
7821 return lookup_attribute ("type generic",
7822 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7828 /* Returns the decl of the dispatcher function if FN is a function version. */
7831 get_function_version_dispatcher (tree fn
)
7833 tree dispatcher_decl
= NULL
;
7835 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7836 && DECL_FUNCTION_VERSIONED (fn
));
7838 gcc_assert (targetm
.get_function_versions_dispatcher
);
7839 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7841 if (dispatcher_decl
== NULL
)
7843 error_at (input_location
, "use of multiversioned function "
7844 "without a default");
7848 retrofit_lang_decl (dispatcher_decl
);
7849 gcc_assert (dispatcher_decl
!= NULL
);
7850 return dispatcher_decl
;
7853 /* fn is a function version dispatcher that is marked used. Mark all the
7854 semantically identical function versions it will dispatch as used. */
7857 mark_versions_used (tree fn
)
7859 struct cgraph_node
*node
;
7860 struct cgraph_function_version_info
*node_v
;
7861 struct cgraph_function_version_info
*it_v
;
7863 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7865 node
= cgraph_node::get (fn
);
7869 gcc_assert (node
->dispatcher_function
);
7871 node_v
= node
->function_version ();
7875 /* All semantically identical versions are chained. Traverse and mark each
7876 one of them as used. */
7877 it_v
= node_v
->next
;
7878 while (it_v
!= NULL
)
7880 mark_used (it_v
->this_node
->decl
);
7885 /* Build a call to "the copy constructor" for the type of A, even if it
7886 wouldn't be selected by normal overload resolution. Used for
7890 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7892 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7893 tree binfo
= TYPE_BINFO (ctype
);
7894 tree copy
= get_copy_ctor (ctype
, complain
);
7895 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7896 tree ob
= build_dummy_object (ctype
);
7897 releasing_vec
args (make_tree_vector_single (a
));
7898 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7899 LOOKUP_NORMAL
, NULL
, complain
);
7903 /* Return true iff T refers to a base field. */
7906 is_base_field_ref (tree t
)
7909 if (TREE_CODE (t
) == ADDR_EXPR
)
7910 t
= TREE_OPERAND (t
, 0);
7911 if (TREE_CODE (t
) == COMPONENT_REF
)
7912 t
= TREE_OPERAND (t
, 1);
7913 if (TREE_CODE (t
) == FIELD_DECL
)
7914 return DECL_FIELD_IS_BASE (t
);
7918 /* We can't elide a copy from a function returning by value to a base
7919 subobject, as the callee might clobber tail padding. Return true iff this
7920 could be that case. */
7923 unsafe_copy_elision_p (tree target
, tree exp
)
7925 /* Copy elision only happens with a TARGET_EXPR. */
7926 if (TREE_CODE (exp
) != TARGET_EXPR
)
7928 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7929 /* It's safe to elide the copy for a class with no tail padding. */
7930 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7932 /* It's safe to elide the copy if we aren't initializing a base object. */
7933 if (!is_base_field_ref (target
))
7935 tree init
= TARGET_EXPR_INITIAL (exp
);
7936 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7937 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7938 init
= TREE_OPERAND (init
, 1);
7939 if (TREE_CODE (init
) == COND_EXPR
)
7941 /* We'll end up copying from each of the arms of the COND_EXPR directly
7942 into the target, so look at them. */
7943 if (tree op
= TREE_OPERAND (init
, 1))
7944 if (unsafe_copy_elision_p (target
, op
))
7946 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7948 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7949 && !AGGR_INIT_VIA_CTOR_P (init
));
7952 /* True iff C is a conversion that binds a reference to a prvalue. */
7955 conv_binds_ref_to_prvalue (conversion
*c
)
7957 if (c
->kind
!= ck_ref_bind
)
7959 if (c
->need_temporary_p
)
7962 c
= next_conversion (c
);
7964 if (c
->kind
== ck_rvalue
)
7966 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7968 if (c
->kind
== ck_identity
&& c
->u
.expr
7969 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7975 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7976 class type or a pointer to class type. */
7979 build_trivial_dtor_call (tree instance
)
7981 gcc_assert (!is_dummy_object (instance
));
7983 if (!flag_lifetime_dse
)
7986 return fold_convert (void_type_node
, instance
);
7989 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
7991 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7993 instance
= cp_build_fold_indirect_ref (instance
);
7996 /* A trivial destructor should still clobber the object. */
7997 tree clobber
= build_clobber (TREE_TYPE (instance
));
7998 return build2 (MODIFY_EXPR
, void_type_node
,
8002 /* Subroutine of the various build_*_call functions. Overload resolution
8003 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
8004 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
8005 bitmask of various LOOKUP_* flags which apply to the call itself. */
8008 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
8011 const vec
<tree
, va_gc
> *args
= cand
->args
;
8012 tree first_arg
= cand
->first_arg
;
8013 conversion
**convs
= cand
->convs
;
8015 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
8020 unsigned int arg_index
= 0;
8024 bool already_used
= false;
8026 /* In a template, there is no need to perform all of the work that
8027 is normally done. We are only interested in the type of the call
8028 expression, i.e., the return type of the function. Any semantic
8029 errors will be deferred until the template is instantiated. */
8030 if (processing_template_decl
)
8034 const tree
*argarray
;
8037 if (undeduced_auto_decl (fn
))
8038 mark_used (fn
, complain
);
8040 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
8044 return_type
= TREE_TYPE (TREE_TYPE (fn
));
8045 nargs
= vec_safe_length (args
);
8046 if (first_arg
== NULL_TREE
)
8047 argarray
= args
->address ();
8055 alcarray
= XALLOCAVEC (tree
, nargs
);
8056 alcarray
[0] = build_this (first_arg
);
8057 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
8058 alcarray
[ix
+ 1] = arg
;
8059 argarray
= alcarray
;
8062 addr
= build_addr_func (fn
, complain
);
8063 if (addr
== error_mark_node
)
8064 return error_mark_node
;
8065 expr
= build_call_array_loc (input_location
, return_type
,
8066 addr
, nargs
, argarray
);
8067 if (TREE_THIS_VOLATILE (fn
) && cfun
)
8068 current_function_returns_abnormally
= 1;
8069 return convert_from_reference (expr
);
8072 /* Give any warnings we noticed during overload resolution. */
8073 if (cand
->warnings
&& (complain
& tf_warning
))
8075 struct candidate_warning
*w
;
8076 for (w
= cand
->warnings
; w
; w
= w
->next
)
8077 joust (cand
, w
->loser
, 1, complain
);
8080 /* Core issue 2327: P0135 doesn't say how to handle the case where the
8081 argument to the copy constructor ends up being a prvalue after
8082 conversion. Let's do the normal processing, but pretend we aren't
8083 actually using the copy constructor. */
8084 bool force_elide
= false;
8085 if (cxx_dialect
>= cxx17
8086 && cand
->num_convs
== 1
8087 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
8088 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8089 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8090 && conv_binds_ref_to_prvalue (convs
[0]))
8093 goto not_really_used
;
8096 /* OK, we're actually calling this inherited constructor; set its deletedness
8097 appropriately. We can get away with doing this here because calling is
8098 the only way to refer to a constructor. */
8099 if (DECL_INHERITED_CTOR (fn
))
8100 deduce_inheriting_ctor (fn
);
8102 /* Make =delete work with SFINAE. */
8103 if (DECL_DELETED_FN (fn
))
8105 if (complain
& tf_error
)
8107 return error_mark_node
;
8110 if (DECL_FUNCTION_MEMBER_P (fn
))
8113 /* If FN is a template function, two cases must be considered.
8118 template <class T> void f();
8120 template <class T> struct B {
8124 struct C : A, B<int> {
8126 using B<int>::g; // #2
8129 In case #1 where `A::f' is a member template, DECL_ACCESS is
8130 recorded in the primary template but not in its specialization.
8131 We check access of FN using its primary template.
8133 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
8134 because it is a member of class template B, DECL_ACCESS is
8135 recorded in the specialization `B<int>::g'. We cannot use its
8136 primary template because `B<T>::g' and `B<int>::g' may have
8137 different access. */
8138 if (DECL_TEMPLATE_INFO (fn
)
8139 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
8140 access_fn
= DECL_TI_TEMPLATE (fn
);
8143 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
8145 return error_mark_node
;
8148 /* If we're checking for implicit delete, don't bother with argument
8150 if (flags
& LOOKUP_SPECULATIVE
)
8152 if (cand
->viable
== 1)
8154 else if (!(complain
& tf_error
))
8155 /* Reject bad conversions now. */
8156 return error_mark_node
;
8157 /* else continue to get conversion error. */
8162 /* N3276 magic doesn't apply to nested calls. */
8163 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8164 complain
&= ~tf_decltype
;
8165 /* No-Cleanup doesn't apply to nested calls either. */
8166 tsubst_flags_t no_cleanup_complain
= complain
;
8167 complain
&= ~tf_no_cleanup
;
8169 /* Find maximum size of vector to hold converted arguments. */
8170 parmlen
= list_length (parm
);
8171 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8172 if (parmlen
> nargs
)
8174 argarray
= XALLOCAVEC (tree
, nargs
);
8176 /* The implicit parameters to a constructor are not considered by overload
8177 resolution, and must be of the proper type. */
8178 if (DECL_CONSTRUCTOR_P (fn
))
8181 if (first_arg
!= NULL_TREE
)
8183 object_arg
= first_arg
;
8184 first_arg
= NULL_TREE
;
8188 object_arg
= (*args
)[arg_index
];
8191 argarray
[j
++] = build_this (object_arg
);
8192 parm
= TREE_CHAIN (parm
);
8193 /* We should never try to call the abstract constructor. */
8194 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8196 if (DECL_HAS_VTT_PARM_P (fn
))
8198 argarray
[j
++] = (*args
)[arg_index
];
8200 parm
= TREE_CHAIN (parm
);
8203 if (flags
& LOOKUP_PREFER_RVALUE
)
8205 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8206 the first parameter of the selected constructor is not an rvalue
8207 reference to the object's type (possibly cv-qualified)...." */
8208 gcc_assert (!(complain
& tf_error
));
8209 tree ptype
= convs
[0]->type
;
8210 if (!TYPE_REF_P (ptype
)
8211 || !TYPE_REF_IS_RVALUE (ptype
)
8212 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8213 return error_mark_node
;
8216 /* Bypass access control for 'this' parameter. */
8217 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8219 tree parmtype
= TREE_VALUE (parm
);
8220 tree arg
= build_this (first_arg
!= NULL_TREE
8222 : (*args
)[arg_index
]);
8223 tree argtype
= TREE_TYPE (arg
);
8227 if (arg
== error_mark_node
)
8228 return error_mark_node
;
8230 if (convs
[i
]->bad_p
)
8232 if (complain
& tf_error
)
8234 auto_diagnostic_group d
;
8235 if (permerror (input_location
, "passing %qT as %<this%> "
8236 "argument discards qualifiers",
8237 TREE_TYPE (argtype
)))
8238 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8241 return error_mark_node
;
8244 /* See if the function member or the whole class type is declared
8245 final and the call can be devirtualized. */
8246 if (DECL_FINAL_P (fn
)
8247 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
8248 flags
|= LOOKUP_NONVIRTUAL
;
8250 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8251 X is called for an object that is not of type X, or of a type
8252 derived from X, the behavior is undefined.
8254 So we can assume that anything passed as 'this' is non-null, and
8255 optimize accordingly. */
8256 gcc_assert (TYPE_PTR_P (parmtype
));
8257 /* Convert to the base in which the function was declared. */
8258 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8259 converted_arg
= build_base_path (PLUS_EXPR
,
8261 cand
->conversion_path
,
8263 /* Check that the base class is accessible. */
8264 if (!accessible_base_p (TREE_TYPE (argtype
),
8265 BINFO_TYPE (cand
->conversion_path
), true))
8267 if (complain
& tf_error
)
8268 error ("%qT is not an accessible base of %qT",
8269 BINFO_TYPE (cand
->conversion_path
),
8270 TREE_TYPE (argtype
));
8272 return error_mark_node
;
8274 /* If fn was found by a using declaration, the conversion path
8275 will be to the derived class, not the base declaring fn. We
8276 must convert from derived to base. */
8277 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8278 TREE_TYPE (parmtype
), ba_unique
,
8280 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8281 base_binfo
, 1, complain
);
8283 argarray
[j
++] = converted_arg
;
8284 parm
= TREE_CHAIN (parm
);
8285 if (first_arg
!= NULL_TREE
)
8286 first_arg
= NULL_TREE
;
8293 gcc_assert (first_arg
== NULL_TREE
);
8294 for (; arg_index
< vec_safe_length (args
) && parm
;
8295 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8297 tree type
= TREE_VALUE (parm
);
8298 tree arg
= (*args
)[arg_index
];
8299 bool conversion_warning
= true;
8303 /* If the argument is NULL and used to (implicitly) instantiate a
8304 template function (and bind one of the template arguments to
8305 the type of 'long int'), we don't want to warn about passing NULL
8306 to non-pointer argument.
8307 For example, if we have this template function:
8309 template<typename T> void func(T x) {}
8311 we want to warn (when -Wconversion is enabled) in this case:
8317 but not in this case:
8323 if (null_node_p (arg
)
8324 && DECL_TEMPLATE_INFO (fn
)
8325 && cand
->template_decl
8326 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8327 conversion_warning
= false;
8329 /* Warn about initializer_list deduction that isn't currently in the
8331 if (cxx_dialect
> cxx98
8332 && flag_deduce_init_list
8333 && cand
->template_decl
8334 && is_std_init_list (non_reference (type
))
8335 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
8337 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
8338 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
8339 tree patparm
= get_pattern_parm (realparm
, tmpl
);
8340 tree pattype
= TREE_TYPE (patparm
);
8341 if (PACK_EXPANSION_P (pattype
))
8342 pattype
= PACK_EXPANSION_PATTERN (pattype
);
8343 pattype
= non_reference (pattype
);
8345 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
8346 && (cand
->explicit_targs
== NULL_TREE
8347 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
8348 <= TEMPLATE_TYPE_IDX (pattype
))))
8350 pedwarn (input_location
, 0, "deducing %qT as %qT",
8351 non_reference (TREE_TYPE (patparm
)),
8352 non_reference (type
));
8353 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
8354 " in call to %qD", cand
->fn
);
8355 pedwarn (input_location
, 0,
8356 " (you can disable this with "
8357 "%<-fno-deduce-init-list%>)");
8361 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8362 knows not to allow any more UDCs. This needs to happen after we
8363 process cand->warnings. */
8364 if (flags
& LOOKUP_NO_CONVERSION
)
8365 conv
->user_conv_p
= true;
8367 tsubst_flags_t arg_complain
= complain
;
8368 if (!conversion_warning
)
8369 arg_complain
&= ~tf_warning
;
8371 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8373 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8375 if (val
== error_mark_node
)
8376 return error_mark_node
;
8378 argarray
[j
++] = val
;
8381 /* Default arguments */
8382 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8384 if (TREE_VALUE (parm
) == error_mark_node
)
8385 return error_mark_node
;
8386 val
= convert_default_arg (TREE_VALUE (parm
),
8387 TREE_PURPOSE (parm
),
8390 if (val
== error_mark_node
)
8391 return error_mark_node
;
8392 argarray
[j
++] = val
;
8396 int magic
= magic_varargs_p (fn
);
8397 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8399 tree a
= (*args
)[arg_index
];
8400 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8402 /* Do no conversions for certain magic varargs. */
8403 a
= mark_type_use (a
);
8404 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8405 return error_mark_node
;
8407 else if (magic
!= 0)
8408 /* For other magic varargs only do decay_conversion. */
8409 a
= decay_conversion (a
, complain
);
8410 else if (DECL_CONSTRUCTOR_P (fn
)
8411 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8414 /* Avoid infinite recursion trying to call A(...). */
8415 if (complain
& tf_error
)
8416 /* Try to call the actual copy constructor for a good error. */
8417 call_copy_ctor (a
, complain
);
8418 return error_mark_node
;
8421 a
= convert_arg_to_ellipsis (a
, complain
);
8422 if (a
== error_mark_node
)
8423 return error_mark_node
;
8427 gcc_assert (j
<= nargs
);
8430 /* Avoid to do argument-transformation, if warnings for format, and for
8431 nonnull are disabled. Just in case that at least one of them is active
8432 the check_function_arguments function might warn about something. */
8434 bool warned_p
= false;
8437 || warn_suggest_attribute_format
8440 tree
*fargs
= (!nargs
? argarray
8441 : (tree
*) alloca (nargs
* sizeof (tree
)));
8442 for (j
= 0; j
< nargs
; j
++)
8444 /* For -Wformat undo the implicit passing by hidden reference
8445 done by convert_arg_to_ellipsis. */
8446 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8447 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8448 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8450 fargs
[j
] = argarray
[j
];
8453 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8454 nargs
, fargs
, NULL
);
8457 if (DECL_INHERITED_CTOR (fn
))
8459 /* Check for passing ellipsis arguments to an inherited constructor. We
8460 could handle this by open-coding the inherited constructor rather than
8461 defining it, but let's not bother now. */
8462 if (!cp_unevaluated_operand
8464 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8466 if (complain
& tf_error
)
8468 sorry ("passing arguments to ellipsis of inherited constructor "
8470 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8472 return error_mark_node
;
8475 /* A base constructor inheriting from a virtual base doesn't get the
8476 inherited arguments, just this and __vtt. */
8477 if (ctor_omit_inherited_parms (fn
))
8481 /* Avoid actually calling copy constructors and copy assignment operators,
8484 if (! flag_elide_constructors
&& !force_elide
)
8485 /* Do things the hard way. */;
8486 else if (cand
->num_convs
== 1
8487 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8488 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8489 /* It's unsafe to elide the constructor when handling
8490 a noexcept-expression, it may evaluate to the wrong
8491 value (c++/53025). */
8492 && (force_elide
|| cp_noexcept_operand
== 0))
8495 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8497 bool trivial
= trivial_fn_p (fn
);
8499 /* Pull out the real argument, disregarding const-correctness. */
8501 /* Strip the reference binding for the constructor parameter. */
8502 if (CONVERT_EXPR_P (targ
)
8503 && TYPE_REF_P (TREE_TYPE (targ
)))
8504 targ
= TREE_OPERAND (targ
, 0);
8505 /* But don't strip any other reference bindings; binding a temporary to a
8506 reference prevents copy elision. */
8507 while ((CONVERT_EXPR_P (targ
)
8508 && !TYPE_REF_P (TREE_TYPE (targ
)))
8509 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8510 targ
= TREE_OPERAND (targ
, 0);
8511 if (TREE_CODE (targ
) == ADDR_EXPR
)
8513 targ
= TREE_OPERAND (targ
, 0);
8514 if (!same_type_ignoring_top_level_qualifiers_p
8515 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8524 arg
= cp_build_fold_indirect_ref (arg
);
8526 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8528 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8529 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8531 /* It's from binding the ref parm to a packed field. */
8532 || convs
[0]->need_temporary_p
8534 /* See unsafe_copy_elision_p. */
8535 || DECL_BASE_CONSTRUCTOR_P (fn
));
8538 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8539 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8541 /* [class.copy]: the copy constructor is implicitly defined even if the
8542 implementation elided its use. But don't warn about deprecation when
8543 eliding a temporary, as then no copy is actually performed. */
8544 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8546 /* The language says this isn't called. */;
8549 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8550 return error_mark_node
;
8551 already_used
= true;
8554 cp_warn_deprecated_use (fn
, complain
);
8556 /* If we're creating a temp and we already have one, don't create a
8557 new one. If we're not creating a temp but we get one, use
8558 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8559 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8560 temp or an INIT_EXPR otherwise. */
8561 if (is_dummy_object (fa
))
8563 if (TREE_CODE (arg
) == TARGET_EXPR
)
8566 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8568 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8571 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8573 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8577 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8578 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8579 && trivial_fn_p (fn
))
8581 tree to
= cp_stabilize_reference
8582 (cp_build_fold_indirect_ref (argarray
[0]));
8583 tree type
= TREE_TYPE (to
);
8584 tree as_base
= CLASSTYPE_AS_BASE (type
);
8585 tree arg
= argarray
[1];
8586 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
8588 if (is_really_empty_class (type
, /*ignore_vptr*/true))
8590 /* Avoid copying empty classes. */
8591 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8592 TREE_NO_WARNING (val
) = 1;
8594 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8596 if (is_std_init_list (type
)
8597 && conv_binds_ref_to_prvalue (convs
[1]))
8598 warning_at (loc
, OPT_Winit_list_lifetime
,
8599 "assignment from temporary %<initializer_list%> does "
8600 "not extend the lifetime of the underlying array");
8601 arg
= cp_build_fold_indirect_ref (arg
);
8602 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8606 /* We must only copy the non-tail padding parts. */
8608 tree array_type
, alias_set
;
8610 arg2
= TYPE_SIZE_UNIT (as_base
);
8611 arg0
= cp_build_addr_expr (to
, complain
);
8613 array_type
= build_array_type (unsigned_char_type_node
,
8615 (size_binop (MINUS_EXPR
,
8616 arg2
, size_int (1))));
8617 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8618 t
= build2 (MODIFY_EXPR
, void_type_node
,
8619 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8620 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8621 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8622 TREE_NO_WARNING (val
) = 1;
8625 cp_warn_deprecated_use (fn
, complain
);
8629 else if (trivial_fn_p (fn
))
8631 if (DECL_DESTRUCTOR_P (fn
))
8632 return build_trivial_dtor_call (argarray
[0]);
8633 else if (default_ctor_p (fn
))
8635 if (is_dummy_object (argarray
[0]))
8636 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8637 no_cleanup_complain
);
8639 return cp_build_fold_indirect_ref (argarray
[0]);
8643 gcc_assert (!force_elide
);
8646 && !mark_used (fn
, complain
))
8647 return error_mark_node
;
8649 /* Warn if the built-in writes to an object of a non-trivial type. */
8650 if (warn_class_memaccess
8651 && vec_safe_length (args
) >= 2
8652 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8653 maybe_warn_class_memaccess (input_location
, fn
, args
);
8655 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8658 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8660 ba_any
, NULL
, complain
);
8661 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8663 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8665 if (TREE_SIDE_EFFECTS (argarray
[0]))
8666 argarray
[0] = save_expr (argarray
[0]);
8667 t
= build_pointer_type (TREE_TYPE (fn
));
8668 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8673 fn
= build_addr_func (fn
, complain
);
8674 if (fn
== error_mark_node
)
8675 return error_mark_node
;
8678 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8679 if (call
== error_mark_node
)
8681 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8683 tree c
= extract_call_expr (call
);
8684 /* build_new_op_1 will clear this when appropriate. */
8685 CALL_EXPR_ORDERED_ARGS (c
) = true;
8689 tree c
= extract_call_expr (call
);
8690 if (TREE_CODE (c
) == CALL_EXPR
)
8691 TREE_NO_WARNING (c
) = 1;
8699 /* Return the DECL of the first non-static subobject of class TYPE
8700 that satisfies the predicate PRED or null if none can be found. */
8702 template <class Predicate
>
8704 first_non_static_field (tree type
, Predicate pred
)
8706 if (!type
|| !CLASS_TYPE_P (type
))
8709 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8711 if (TREE_CODE (field
) != FIELD_DECL
)
8713 if (TREE_STATIC (field
))
8721 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8722 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8724 tree base
= TREE_TYPE (base_binfo
);
8727 if (tree field
= first_non_static_field (base
, pred
))
8734 struct NonPublicField
8736 bool operator() (const_tree t
)
8738 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8742 /* Return the DECL of the first non-public subobject of class TYPE
8743 or null if none can be found. */
8746 first_non_public_field (tree type
)
8748 return first_non_static_field (type
, NonPublicField ());
8751 struct NonTrivialField
8753 bool operator() (const_tree t
)
8755 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8759 /* Return the DECL of the first non-trivial subobject of class TYPE
8760 or null if none can be found. */
8763 first_non_trivial_field (tree type
)
8765 return first_non_static_field (type
, NonTrivialField ());
8768 } /* unnamed namespace */
8770 /* Return true if all copy and move assignment operator overloads for
8771 class TYPE are trivial and at least one of them is not deleted and,
8772 when ACCESS is set, accessible. Return false otherwise. Set
8773 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8774 copy or move assignment. */
8777 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8779 tree fns
= get_class_binding (type
, assign_op_identifier
);
8780 bool all_trivial
= true;
8782 /* Iterate over overloads of the assignment operator, checking
8783 accessible copy assignments for triviality. */
8785 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8789 /* Skip operators that aren't copy assignments. */
8793 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8794 || accessible_p (TYPE_BINFO (type
), f
, true));
8796 /* Skip template assignment operators and deleted functions. */
8797 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8803 if (!accessible
|| !trivial_fn_p (f
))
8804 all_trivial
= false;
8806 /* Break early when both properties have been determined. */
8807 if (*hasassign
&& !all_trivial
)
8811 /* Return true if they're all trivial and one of the expressions
8812 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8813 tree ref
= cp_build_reference_type (type
, false);
8815 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8816 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8819 /* Return true if all copy and move ctor overloads for class TYPE are
8820 trivial and at least one of them is not deleted and, when ACCESS is
8821 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8822 to true when the TYPE has a (not necessarily trivial) default and copy
8823 (or move) ctor, respectively. */
8826 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8828 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8829 bool all_trivial
= true;
8831 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8835 /* Skip template constructors. */
8836 if (TREE_CODE (f
) != FUNCTION_DECL
)
8839 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8841 /* Skip ctors other than default, copy, and move. */
8842 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8845 if (DECL_DELETED_FN (f
))
8848 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8849 || accessible_p (TYPE_BINFO (type
), f
, true));
8852 hasctor
[cpy_or_move_ctor_p
] = true;
8854 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8855 all_trivial
= false;
8857 /* Break early when both properties have been determined. */
8858 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8865 /* Issue a warning on a call to the built-in function FNDECL if it is
8866 a raw memory write whose destination is not an object of (something
8867 like) trivial or standard layout type with a non-deleted assignment
8868 and copy ctor. Detects const correctness violations, corrupting
8869 references, virtual table pointers, and bypassing non-trivial
8873 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8874 const vec
<tree
, va_gc
> *args
)
8876 /* Except for bcopy where it's second, the destination pointer is
8877 the first argument for all functions handled here. Compute
8878 the index of the destination and source arguments. */
8879 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8880 unsigned srcidx
= !dstidx
;
8882 tree dest
= (*args
)[dstidx
];
8883 if (!TREE_TYPE (dest
) || !INDIRECT_TYPE_P (TREE_TYPE (dest
)))
8886 tree srctype
= NULL_TREE
;
8888 /* Determine the type of the pointed-to object and whether it's
8889 a complete class type. */
8890 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8892 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8895 /* Check to see if the raw memory call is made by a non-static member
8896 function with THIS as the destination argument for the destination
8897 type. If so, and if the class has no non-trivial bases or members,
8898 be more permissive. */
8899 if (current_function_decl
8900 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8901 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8903 tree ctx
= DECL_CONTEXT (current_function_decl
);
8904 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8905 tree binfo
= TYPE_BINFO (ctx
);
8908 && !BINFO_VTABLE (binfo
)
8909 && !first_non_trivial_field (desttype
))
8913 /* True if the class is trivial. */
8914 bool trivial
= trivial_type_p (desttype
);
8916 /* Set to true if DESTYPE has an accessible copy assignment. */
8917 bool hasassign
= false;
8918 /* True if all of the class' overloaded copy assignment operators
8919 are all trivial (and not deleted) and at least one of them is
8921 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8923 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8925 bool hasctors
[2] = { false, false };
8927 /* True if all of the class' overloaded copy constructors are all
8928 trivial (and not deleted) and at least one of them is accessible. */
8929 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8931 /* Set FLD to the first private/protected member of the class. */
8932 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8934 /* The warning format string. */
8935 const char *warnfmt
= NULL
;
8936 /* A suggested alternative to offer instead of the raw memory call.
8937 Empty string when none can be come up with. */
8938 const char *suggest
= "";
8939 bool warned
= false;
8941 switch (DECL_FUNCTION_CODE (fndecl
))
8943 case BUILT_IN_MEMSET
:
8944 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8946 /* Diagnose setting non-copy-assignable or non-trivial types,
8947 or types with a private member, to (potentially) non-zero
8948 bytes. Since the value of the bytes being written is unknown,
8949 suggest using assignment instead (if one exists). Also warn
8950 for writes into objects for which zero-initialization doesn't
8951 mean all bits clear (pointer-to-member data, where null is all
8952 bits set). Since the value being written is (most likely)
8953 non-zero, simply suggest assignment (but not copy assignment). */
8954 suggest
= "; use assignment instead";
8956 warnfmt
= G_("%qD writing to an object of type %#qT with "
8957 "no trivial copy-assignment");
8959 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8962 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8963 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8964 "%qD writing to an object of type %#qT with "
8966 fndecl
, desttype
, access
, fld
);
8968 else if (!zero_init_p (desttype
))
8969 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8970 "a pointer to data member%s");
8976 case BUILT_IN_BZERO
:
8977 /* Similarly to the above, diagnose clearing non-trivial or non-
8978 standard layout objects, or objects of types with no assignmenmt.
8979 Since the value being written is known to be zero, suggest either
8980 copy assignment, copy ctor, or default ctor as an alternative,
8981 depending on what's available. */
8983 if (hasassign
&& hasctors
[0])
8984 suggest
= G_("; use assignment or value-initialization instead");
8986 suggest
= G_("; use assignment instead");
8987 else if (hasctors
[0])
8988 suggest
= G_("; use value-initialization instead");
8991 warnfmt
= G_("%qD clearing an object of type %#qT with "
8992 "no trivial copy-assignment%s");
8994 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8995 else if (!zero_init_p (desttype
))
8996 warnfmt
= G_("%qD clearing an object of type %#qT containing "
8997 "a pointer-to-member%s");
9000 case BUILT_IN_BCOPY
:
9001 case BUILT_IN_MEMCPY
:
9002 case BUILT_IN_MEMMOVE
:
9003 case BUILT_IN_MEMPCPY
:
9004 /* Determine the type of the source object. */
9005 srctype
= TREE_TYPE ((*args
)[srcidx
]);
9006 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
9007 srctype
= void_type_node
;
9009 srctype
= TREE_TYPE (srctype
);
9011 /* Since it's impossible to determine wheter the byte copy is
9012 being used in place of assignment to an existing object or
9013 as a substitute for initialization, assume it's the former.
9014 Determine the best alternative to use instead depending on
9015 what's not deleted. */
9016 if (hasassign
&& hasctors
[1])
9017 suggest
= G_("; use copy-assignment or copy-initialization instead");
9019 suggest
= G_("; use copy-assignment instead");
9020 else if (hasctors
[1])
9021 suggest
= G_("; use copy-initialization instead");
9024 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
9025 "copy-assignment%s");
9026 else if (!trivially_copyable_p (desttype
))
9027 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
9030 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
9033 && !VOID_TYPE_P (srctype
)
9034 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9035 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9038 /* Warn when copying into a non-trivial object from an object
9039 of a different type other than void or char. */
9040 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9041 "%qD copying an object of non-trivial type "
9042 "%#qT from an array of %#qT",
9043 fndecl
, desttype
, srctype
);
9046 && !VOID_TYPE_P (srctype
)
9047 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9048 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9051 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
9052 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9053 "%qD copying an object of type %#qT with "
9054 "%qs member %qD from an array of %#qT; use "
9055 "assignment or copy-initialization instead",
9056 fndecl
, desttype
, access
, fld
, srctype
);
9058 else if (!trivial
&& vec_safe_length (args
) > 2)
9060 tree sz
= maybe_constant_value ((*args
)[2]);
9061 if (!tree_fits_uhwi_p (sz
))
9064 /* Finally, warn on partial copies. */
9065 unsigned HOST_WIDE_INT typesize
9066 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
9067 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
9068 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9069 (typesize
- partial
> 1
9070 ? G_("%qD writing to an object of "
9071 "a non-trivial type %#qT leaves %wu "
9073 : G_("%qD writing to an object of "
9074 "a non-trivial type %#qT leaves %wu "
9076 fndecl
, desttype
, typesize
- partial
);
9080 case BUILT_IN_REALLOC
:
9082 if (!trivially_copyable_p (desttype
))
9083 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
9084 "%#qT; use %<new%> and %<delete%> instead");
9086 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
9087 "constructor; use %<new%> and %<delete%> instead");
9088 else if (!get_dtor (desttype
, tf_none
))
9089 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
9093 tree sz
= maybe_constant_value ((*args
)[1]);
9094 if (TREE_CODE (sz
) == INTEGER_CST
9095 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
9096 /* Finally, warn on reallocation into insufficient space. */
9097 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9098 "%qD moving an object of non-trivial type "
9099 "%#qT and size %E into a region of size %E",
9100 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
9112 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9113 warnfmt
, fndecl
, desttype
, suggest
);
9115 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9116 warnfmt
, fndecl
, desttype
);
9120 inform (location_of (desttype
), "%#qT declared here", desttype
);
9123 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
9124 This function performs no overload resolution, conversion, or other
9125 high-level operations. */
9128 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
9129 tsubst_flags_t complain
)
9133 /* Remember roughly where this call is. */
9134 location_t loc
= cp_expr_loc_or_loc (fn
, input_location
);
9135 fn
= build_call_a (fn
, nargs
, argarray
);
9136 SET_EXPR_LOCATION (fn
, loc
);
9138 fndecl
= get_callee_fndecl (fn
);
9140 /* Check that arguments to builtin functions match the expectations. */
9142 && !processing_template_decl
9143 && fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
9147 /* We need to take care that values to BUILT_IN_NORMAL
9149 for (i
= 0; i
< nargs
; i
++)
9150 argarray
[i
] = maybe_constant_value (argarray
[i
]);
9152 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
9154 return error_mark_node
;
9157 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9160 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9161 function call is either the operand of a decltype-specifier or the
9162 right operand of a comma operator that is the operand of a
9163 decltype-specifier, a temporary object is not introduced for the
9164 prvalue. The type of the prvalue may be incomplete. */
9165 if (!(complain
& tf_decltype
))
9167 fn
= require_complete_type_sfinae (fn
, complain
);
9168 if (fn
== error_mark_node
)
9169 return error_mark_node
;
9171 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9173 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9174 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9177 return convert_from_reference (fn
);
9180 /* Returns the value to use for the in-charge parameter when making a
9181 call to a function with the indicated NAME.
9183 FIXME:Can't we find a neater way to do this mapping? */
9186 in_charge_arg_for_name (tree name
)
9188 if (IDENTIFIER_CTOR_P (name
))
9190 if (name
== complete_ctor_identifier
)
9191 return integer_one_node
;
9192 gcc_checking_assert (name
== base_ctor_identifier
);
9196 if (name
== complete_dtor_identifier
)
9197 return integer_two_node
;
9198 else if (name
== deleting_dtor_identifier
)
9199 return integer_three_node
;
9200 gcc_checking_assert (name
== base_dtor_identifier
);
9203 return integer_zero_node
;
9206 /* We've built up a constructor call RET. Complain if it delegates to the
9207 constructor we're currently compiling. */
9210 check_self_delegation (tree ret
)
9212 if (TREE_CODE (ret
) == TARGET_EXPR
)
9213 ret
= TARGET_EXPR_INITIAL (ret
);
9214 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9215 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9216 error ("constructor delegates to itself");
9219 /* Build a call to a constructor, destructor, or an assignment
9220 operator for INSTANCE, an expression with class type. NAME
9221 indicates the special member function to call; *ARGS are the
9222 arguments. ARGS may be NULL. This may change ARGS. BINFO
9223 indicates the base of INSTANCE that is to be passed as the `this'
9224 parameter to the member function called.
9226 FLAGS are the LOOKUP_* flags to use when processing the call.
9228 If NAME indicates a complete object constructor, INSTANCE may be
9229 NULL_TREE. In this case, the caller will call build_cplus_new to
9230 store the newly constructed object into a VAR_DECL. */
9233 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9234 tree binfo
, int flags
, tsubst_flags_t complain
)
9237 /* The type of the subobject to be constructed or destroyed. */
9239 vec
<tree
, va_gc
> *allocated
= NULL
;
9242 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9244 if (error_operand_p (instance
))
9245 return error_mark_node
;
9247 if (IDENTIFIER_DTOR_P (name
))
9249 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9250 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9251 /* Shortcut to avoid lazy destructor declaration. */
9252 return build_trivial_dtor_call (instance
);
9257 /* Resolve the name. */
9258 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9259 return error_mark_node
;
9261 binfo
= TYPE_BINFO (binfo
);
9264 gcc_assert (binfo
!= NULL_TREE
);
9266 class_type
= BINFO_TYPE (binfo
);
9268 /* Handle the special case where INSTANCE is NULL_TREE. */
9269 if (name
== complete_ctor_identifier
&& !instance
)
9270 instance
= build_dummy_object (class_type
);
9273 /* Convert to the base class, if necessary. */
9274 if (!same_type_ignoring_top_level_qualifiers_p
9275 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9277 if (IDENTIFIER_CDTOR_P (name
))
9278 /* For constructors and destructors, either the base is
9279 non-virtual, or it is virtual but we are doing the
9280 conversion from a constructor or destructor for the
9281 complete object. In either case, we can convert
9283 instance
= convert_to_base_statically (instance
, binfo
);
9286 /* However, for assignment operators, we must convert
9287 dynamically if the base is virtual. */
9288 gcc_checking_assert (name
== assign_op_identifier
);
9289 instance
= build_base_path (PLUS_EXPR
, instance
,
9290 binfo
, /*nonnull=*/1, complain
);
9295 gcc_assert (instance
!= NULL_TREE
);
9297 /* In C++17, "If the initializer expression is a prvalue and the
9298 cv-unqualified version of the source type is the same class as the class
9299 of the destination, the initializer expression is used to initialize the
9300 destination object." Handle that here to avoid doing overload
9302 if (cxx_dialect
>= cxx17
9303 && args
&& vec_safe_length (*args
) == 1
9304 && name
== complete_ctor_identifier
)
9306 tree arg
= (**args
)[0];
9308 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9309 && !TYPE_HAS_LIST_CTOR (class_type
)
9310 && CONSTRUCTOR_NELTS (arg
) == 1)
9311 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9313 if ((TREE_CODE (arg
) == TARGET_EXPR
9314 || TREE_CODE (arg
) == CONSTRUCTOR
)
9315 && (same_type_ignoring_top_level_qualifiers_p
9316 (class_type
, TREE_TYPE (arg
))))
9318 if (is_dummy_object (instance
))
9320 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9321 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9323 if ((complain
& tf_error
)
9324 && (flags
& LOOKUP_DELEGATING_CONS
))
9325 check_self_delegation (arg
);
9326 /* Avoid change of behavior on Wunused-var-2.C. */
9327 instance
= mark_lvalue_use (instance
);
9328 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9332 fns
= lookup_fnfields (binfo
, name
, 1);
9334 /* When making a call to a constructor or destructor for a subobject
9335 that uses virtual base classes, pass down a pointer to a VTT for
9337 if ((name
== base_ctor_identifier
9338 || name
== base_dtor_identifier
)
9339 && CLASSTYPE_VBASECLASSES (class_type
))
9344 /* If the current function is a complete object constructor
9345 or destructor, then we fetch the VTT directly.
9346 Otherwise, we look it up using the VTT we were given. */
9347 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9348 vtt
= decay_conversion (vtt
, complain
);
9349 if (vtt
== error_mark_node
)
9350 return error_mark_node
;
9351 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9352 if (BINFO_SUBVTT_INDEX (binfo
))
9353 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9359 allocated
= make_tree_vector ();
9363 vec_safe_insert (*args
, 0, sub_vtt
);
9366 ret
= build_new_method_call (instance
, fns
, args
,
9367 TYPE_BINFO (BINFO_TYPE (binfo
)),
9371 if (allocated
!= NULL
)
9372 release_tree_vector (allocated
);
9374 if ((complain
& tf_error
)
9375 && (flags
& LOOKUP_DELEGATING_CONS
)
9376 && name
== complete_ctor_identifier
)
9377 check_self_delegation (ret
);
9382 /* Return the NAME, as a C string. The NAME indicates a function that
9383 is a member of TYPE. *FREE_P is set to true if the caller must
9384 free the memory returned.
9386 Rather than go through all of this, we should simply set the names
9387 of constructors and destructors appropriately, and dispense with
9388 ctor_identifier, dtor_identifier, etc. */
9391 name_as_c_string (tree name
, tree type
, bool *free_p
)
9393 const char *pretty_name
;
9395 /* Assume that we will not allocate memory. */
9397 /* Constructors and destructors are special. */
9398 if (IDENTIFIER_CDTOR_P (name
))
9401 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9402 /* For a destructor, add the '~'. */
9403 if (IDENTIFIER_DTOR_P (name
))
9405 pretty_name
= concat ("~", pretty_name
, NULL
);
9406 /* Remember that we need to free the memory allocated. */
9410 else if (IDENTIFIER_CONV_OP_P (name
))
9412 pretty_name
= concat ("operator ",
9413 type_as_string_translate (TREE_TYPE (name
),
9414 TFF_PLAIN_IDENTIFIER
),
9416 /* Remember that we need to free the memory allocated. */
9420 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9422 return CONST_CAST (char *, pretty_name
);
9425 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9428 static z_candidate
*
9429 single_z_candidate (z_candidate
*candidates
)
9431 if (candidates
== NULL
)
9434 if (candidates
->next
)
9440 /* If CANDIDATE is invalid due to a bad argument type, return the
9441 pertinent conversion_info.
9443 Otherwise, return NULL. */
9445 static const conversion_info
*
9446 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9448 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9449 rejection_reason
*r
= candidate
->reason
;
9459 case rr_arg_conversion
:
9460 return &r
->u
.conversion
;
9462 case rr_bad_arg_conversion
:
9463 return &r
->u
.bad_conversion
;
9467 /* Issue an error and note complaining about a bad argument type at a
9468 callsite with a single candidate FNDECL.
9470 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9471 case input_location is used).
9472 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9473 the formal parameter. */
9476 complain_about_bad_argument (location_t arg_loc
,
9477 tree from_type
, tree to_type
,
9478 tree fndecl
, int parmnum
)
9480 auto_diagnostic_group d
;
9481 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9482 range_label
*label
= &rhs_label
;
9483 if (arg_loc
== UNKNOWN_LOCATION
)
9485 arg_loc
= input_location
;
9488 gcc_rich_location
richloc (arg_loc
, label
);
9490 "cannot convert %qH to %qI",
9491 from_type
, to_type
);
9492 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9496 /* Subroutine of build_new_method_call_1, for where there are no viable
9497 candidates for the call. */
9500 complain_about_no_candidates_for_method_call (tree instance
,
9501 z_candidate
*candidates
,
9502 tree explicit_targs
,
9504 tree optype
, tree name
,
9505 bool skip_first_for_error
,
9506 vec
<tree
, va_gc
> *user_args
)
9508 auto_diagnostic_group d
;
9509 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9510 cxx_incomplete_type_error (instance
, basetype
);
9512 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9513 basetype
, optype
, build_tree_list_vec (user_args
),
9514 TREE_TYPE (instance
));
9517 /* Special-case for when there's a single candidate that's failing
9518 due to a bad argument type. */
9519 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9520 if (const conversion_info
*conv
9521 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9523 complain_about_bad_argument (conv
->loc
,
9524 conv
->from
, conv
->to_type
,
9525 candidate
->fn
, conv
->n_arg
);
9529 tree arglist
= build_tree_list_vec (user_args
);
9530 tree errname
= name
;
9531 bool twiddle
= false;
9532 if (IDENTIFIER_CDTOR_P (errname
))
9534 twiddle
= IDENTIFIER_DTOR_P (errname
);
9535 errname
= constructor_name (basetype
);
9538 errname
= lookup_template_function (errname
, explicit_targs
);
9539 if (skip_first_for_error
)
9540 arglist
= TREE_CHAIN (arglist
);
9541 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9542 basetype
, &"~"[!twiddle
], errname
, arglist
,
9543 TREE_TYPE (instance
));
9545 print_z_candidates (location_of (name
), candidates
);
9548 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9549 be set, upon return, to the function called. ARGS may be NULL.
9550 This may change ARGS. */
9553 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9554 tree conversion_path
, int flags
,
9555 tree
*fn_p
, tsubst_flags_t complain
)
9557 struct z_candidate
*candidates
= 0, *cand
;
9558 tree explicit_targs
= NULL_TREE
;
9559 tree basetype
= NULL_TREE
;
9560 tree access_binfo
, binfo
;
9562 tree first_mem_arg
= NULL_TREE
;
9564 bool skip_first_for_error
;
9565 vec
<tree
, va_gc
> *user_args
;
9568 int template_only
= 0;
9572 vec
<tree
, va_gc
> *orig_args
= NULL
;
9575 gcc_assert (instance
!= NULL_TREE
);
9577 /* We don't know what function we're going to call, yet. */
9581 if (error_operand_p (instance
)
9582 || !fns
|| error_operand_p (fns
))
9583 return error_mark_node
;
9585 if (!BASELINK_P (fns
))
9587 if (complain
& tf_error
)
9588 error ("call to non-function %qD", fns
);
9589 return error_mark_node
;
9592 orig_instance
= instance
;
9595 /* Dismantle the baselink to collect all the information we need. */
9596 if (!conversion_path
)
9597 conversion_path
= BASELINK_BINFO (fns
);
9598 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9599 binfo
= BASELINK_BINFO (fns
);
9600 optype
= BASELINK_OPTYPE (fns
);
9601 fns
= BASELINK_FUNCTIONS (fns
);
9602 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9604 explicit_targs
= TREE_OPERAND (fns
, 1);
9605 fns
= TREE_OPERAND (fns
, 0);
9608 gcc_assert (OVL_P (fns
));
9609 fn
= OVL_FIRST (fns
);
9610 name
= DECL_NAME (fn
);
9612 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9613 gcc_assert (CLASS_TYPE_P (basetype
));
9615 user_args
= args
== NULL
? NULL
: *args
;
9616 /* Under DR 147 A::A() is an invalid constructor call,
9617 not a functional cast. */
9618 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9620 if (! (complain
& tf_error
))
9621 return error_mark_node
;
9623 basetype
= DECL_CONTEXT (fn
);
9624 name
= constructor_name (basetype
);
9625 auto_diagnostic_group d
;
9626 if (permerror (input_location
,
9627 "cannot call constructor %<%T::%D%> directly",
9629 inform (input_location
, "for a function-style cast, remove the "
9630 "redundant %<::%D%>", name
);
9631 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9636 if (processing_template_decl
)
9638 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9639 instance
= build_non_dependent_expr (instance
);
9641 make_args_non_dependent (*args
);
9644 /* Process the argument list. */
9645 if (args
!= NULL
&& *args
!= NULL
)
9647 *args
= resolve_args (*args
, complain
);
9649 return error_mark_node
;
9653 /* Consider the object argument to be used even if we end up selecting a
9654 static member function. */
9655 instance
= mark_type_use (instance
);
9657 /* Figure out whether to skip the first argument for the error
9658 message we will display to users if an error occurs. We don't
9659 want to display any compiler-generated arguments. The "this"
9660 pointer hasn't been added yet. However, we must remove the VTT
9661 pointer if this is a call to a base-class constructor or
9663 skip_first_for_error
= false;
9664 if (IDENTIFIER_CDTOR_P (name
))
9666 /* Callers should explicitly indicate whether they want to ctor
9667 the complete object or just the part without virtual bases. */
9668 gcc_assert (name
!= ctor_identifier
);
9670 /* Remove the VTT pointer, if present. */
9671 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9672 && CLASSTYPE_VBASECLASSES (basetype
))
9673 skip_first_for_error
= true;
9675 /* It's OK to call destructors and constructors on cv-qualified
9676 objects. Therefore, convert the INSTANCE to the unqualified
9677 type, if necessary. */
9678 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9680 instance
= build_this (instance
);
9681 instance
= build_nop (build_pointer_type (basetype
), instance
);
9682 instance
= build_fold_indirect_ref (instance
);
9686 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9688 /* For the overload resolution we need to find the actual `this`
9689 that would be captured if the call turns out to be to a
9690 non-static member function. Do not actually capture it at this
9692 if (DECL_CONSTRUCTOR_P (fn
))
9693 /* Constructors don't use the enclosing 'this'. */
9694 first_mem_arg
= instance
;
9696 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9698 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9699 p
= conversion_obstack_alloc (0);
9701 /* The number of arguments artificial parms in ARGS; we subtract one because
9702 there's no 'this' in ARGS. */
9703 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9705 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9706 initializer, not T({ }). */
9707 if (DECL_CONSTRUCTOR_P (fn
)
9708 && vec_safe_length (user_args
) > skip
9709 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9711 tree init_list
= (*user_args
)[skip
];
9712 tree init
= NULL_TREE
;
9714 gcc_assert (user_args
->length () == skip
+ 1
9715 && !(flags
& LOOKUP_ONLYCONVERTING
));
9717 /* If the initializer list has no elements and T is a class type with
9718 a default constructor, the object is value-initialized. Handle
9719 this here so we don't need to handle it wherever we use
9720 build_special_member_call. */
9721 if (CONSTRUCTOR_NELTS (init_list
) == 0
9722 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9723 /* For a user-provided default constructor, use the normal
9724 mechanisms so that protected access works. */
9725 && type_has_non_user_provided_default_constructor (basetype
)
9726 && !processing_template_decl
)
9727 init
= build_value_init (basetype
, complain
);
9729 /* If BASETYPE is an aggregate, we need to do aggregate
9731 else if (CP_AGGREGATE_TYPE_P (basetype
))
9733 init
= reshape_init (basetype
, init_list
, complain
);
9734 init
= digest_init (basetype
, init
, complain
);
9739 if (is_dummy_object (instance
))
9740 return get_target_expr_sfinae (init
, complain
);
9741 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9742 TREE_SIDE_EFFECTS (init
) = true;
9746 /* Otherwise go ahead with overload resolution. */
9747 add_list_candidates (fns
, first_mem_arg
, user_args
,
9748 basetype
, explicit_targs
, template_only
,
9749 conversion_path
, access_binfo
, flags
,
9750 &candidates
, complain
);
9753 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9754 explicit_targs
, template_only
, conversion_path
,
9755 access_binfo
, flags
, &candidates
, complain
);
9757 any_viable_p
= false;
9758 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9762 if (complain
& tf_error
)
9763 complain_about_no_candidates_for_method_call (instance
, candidates
,
9764 explicit_targs
, basetype
,
9766 skip_first_for_error
,
9768 call
= error_mark_node
;
9772 cand
= tourney (candidates
, complain
);
9779 if (complain
& tf_error
)
9781 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9782 arglist
= build_tree_list_vec (user_args
);
9783 if (skip_first_for_error
)
9784 arglist
= TREE_CHAIN (arglist
);
9785 auto_diagnostic_group d
;
9786 if (!any_strictly_viable (candidates
))
9787 error ("no matching function for call to %<%s(%A)%>",
9788 pretty_name
, arglist
);
9790 error ("call of overloaded %<%s(%A)%> is ambiguous",
9791 pretty_name
, arglist
);
9792 print_z_candidates (location_of (name
), candidates
);
9796 call
= error_mark_node
;
9803 if (!(flags
& LOOKUP_NONVIRTUAL
)
9804 && DECL_PURE_VIRTUAL_P (fn
)
9805 && instance
== current_class_ref
9806 && (complain
& tf_warning
))
9808 /* This is not an error, it is runtime undefined
9810 if (!current_function_decl
)
9811 warning (0, "pure virtual %q#D called from "
9812 "non-static data member initializer", fn
);
9813 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9814 || DECL_DESTRUCTOR_P (current_function_decl
))
9815 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9816 ? G_("pure virtual %q#D called from constructor")
9817 : G_("pure virtual %q#D called from destructor")),
9821 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9822 && !DECL_CONSTRUCTOR_P (fn
)
9823 && is_dummy_object (instance
))
9825 instance
= maybe_resolve_dummy (instance
, true);
9826 if (instance
== error_mark_node
)
9827 call
= error_mark_node
;
9828 else if (!is_dummy_object (instance
))
9830 /* We captured 'this' in the current lambda now that
9831 we know we really need it. */
9832 cand
->first_arg
= instance
;
9834 else if (any_dependent_bases_p ())
9835 /* We can't tell until instantiation time whether we can use
9836 *this as the implicit object argument. */;
9839 if (complain
& tf_error
)
9840 error ("cannot call member function %qD without object",
9842 call
= error_mark_node
;
9846 if (call
!= error_mark_node
)
9848 /* Optimize away vtable lookup if we know that this
9849 function can't be overridden. We need to check if
9850 the context and the type where we found fn are the same,
9851 actually FN might be defined in a different class
9852 type because of a using-declaration. In this case, we
9853 do not want to perform a non-virtual call. */
9854 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9855 && same_type_ignoring_top_level_qualifiers_p
9856 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9857 && resolves_to_fixed_type_p (instance
, 0))
9858 flags
|= LOOKUP_NONVIRTUAL
;
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_loc (expr
, input_location
);
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_loc (expr
, input_location
);
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"