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 (TREE_CODE (fntype
) == FUNCTION_TYPE
361 || TREE_CODE (fntype
) == METHOD_TYPE
);
362 result_type
= TREE_TYPE (fntype
);
363 /* An rvalue has no cv-qualifiers. */
364 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
365 result_type
= cv_unqualified (result_type
);
367 function
= build_call_array_loc (input_location
,
368 result_type
, function
, n
, argarray
);
369 set_flags_from_callee (function
);
371 decl
= get_callee_fndecl (function
);
373 if (decl
&& !TREE_USED (decl
))
375 /* We invoke build_call directly for several library
376 functions. These may have been declared normally if
377 we're building libgcc, so we can't just check
379 gcc_assert (DECL_ARTIFICIAL (decl
)
380 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
385 require_complete_eh_spec_types (fntype
, decl
);
387 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
389 /* Don't pass empty class objects by value. This is useful
390 for tags in STL, which are used to control overload resolution.
391 We don't need to handle other cases of copying empty classes. */
392 if (!decl
|| !fndecl_built_in_p (decl
))
393 for (i
= 0; i
< n
; i
++)
395 tree arg
= CALL_EXPR_ARG (function
, i
);
396 if (is_empty_class (TREE_TYPE (arg
))
397 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
399 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
400 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
401 CALL_EXPR_ARG (function
, i
) = arg
;
408 /* New overloading code. */
412 struct candidate_warning
{
414 candidate_warning
*next
;
417 /* Information for providing diagnostics about why overloading failed. */
419 enum rejection_reason_code
{
422 rr_explicit_conversion
,
423 rr_template_conversion
,
425 rr_bad_arg_conversion
,
426 rr_template_unification
,
429 rr_constraint_failure
432 struct conversion_info
{
433 /* The index of the argument, 0-based. */
435 /* The actual argument or its type. */
437 /* The type of the parameter. */
439 /* The location of the argument. */
443 struct rejection_reason
{
444 enum rejection_reason_code code
;
446 /* Information about an arity mismatch. */
448 /* The expected number of arguments. */
450 /* The actual number of arguments in the call. */
452 /* Whether the call was a varargs call. */
455 /* Information about an argument conversion mismatch. */
456 struct conversion_info conversion
;
457 /* Same, but for bad argument conversions. */
458 struct conversion_info bad_conversion
;
459 /* Information about template unification failures. These are the
460 parameters passed to fn_type_unification. */
468 unification_kind_t strict
;
470 } template_unification
;
471 /* Information about template instantiation failures. These are the
472 parameters passed to instantiate_template. */
476 } template_instantiation
;
481 /* The FUNCTION_DECL that will be called if this candidate is
482 selected by overload resolution. */
484 /* If not NULL_TREE, the first argument to use when calling this
487 /* The rest of the arguments to use when calling this function. If
488 there are no further arguments this may be NULL or it may be an
490 const vec
<tree
, va_gc
> *args
;
491 /* The implicit conversion sequences for each of the arguments to
494 /* The number of implicit conversion sequences. */
496 /* If FN is a user-defined conversion, the standard conversion
497 sequence from the type returned by FN to the desired destination
499 conversion
*second_conv
;
500 struct rejection_reason
*reason
;
501 /* If FN is a member function, the binfo indicating the path used to
502 qualify the name of FN at the call site. This path is used to
503 determine whether or not FN is accessible if it is selected by
504 overload resolution. The DECL_CONTEXT of FN will always be a
505 (possibly improper) base of this binfo. */
507 /* If FN is a non-static member function, the binfo indicating the
508 subobject to which the `this' pointer should be converted if FN
509 is selected by overload resolution. The type pointed to by
510 the `this' pointer must correspond to the most derived class
511 indicated by the CONVERSION_PATH. */
512 tree conversion_path
;
515 candidate_warning
*warnings
;
519 /* The flags active in add_candidate. */
523 /* Returns true iff T is a null pointer constant in the sense of
527 null_ptr_cst_p (tree t
)
529 tree type
= TREE_TYPE (t
);
533 A null pointer constant is an integral constant expression
534 (_expr.const_) rvalue of integer type that evaluates to zero or
535 an rvalue of type std::nullptr_t. */
536 if (NULLPTR_TYPE_P (type
))
539 if (cxx_dialect
>= cxx11
)
541 STRIP_ANY_LOCATION_WRAPPER (t
);
543 /* Core issue 903 says only literal 0 is a null pointer constant. */
544 if (TREE_CODE (type
) == INTEGER_TYPE
545 && !char_type_p (type
)
546 && TREE_CODE (t
) == INTEGER_CST
548 && !TREE_OVERFLOW (t
))
551 else if (CP_INTEGRAL_TYPE_P (type
))
553 t
= fold_non_dependent_expr (t
, tf_none
);
555 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
562 /* Returns true iff T is a null member pointer value (4.11). */
565 null_member_pointer_value_p (tree t
)
567 tree type
= TREE_TYPE (t
);
570 else if (TYPE_PTRMEMFUNC_P (type
))
571 return (TREE_CODE (t
) == CONSTRUCTOR
572 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
573 else if (TYPE_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
.elements () && field_in_pset (pset
, field
))
990 if (i
< CONSTRUCTOR_NELTS (ctor
))
992 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
995 else if (DECL_INITIAL (field
))
996 val
= get_nsdmi (field
, /*ctor*/false, complain
);
997 else if (TYPE_REF_P (ftype
))
998 /* Value-initialization of reference is ill-formed. */
1002 if (empty_ctor
== NULL_TREE
)
1003 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
1007 if (TREE_CODE (ftype
) == ARRAY_TYPE
1008 && TREE_CODE (val
) == CONSTRUCTOR
)
1009 ok
= can_convert_array (ftype
, val
, flags
, complain
);
1011 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
1017 if (TREE_CODE (type
) == UNION_TYPE
)
1021 if (i
< CONSTRUCTOR_NELTS (ctor
))
1024 c
= alloc_conversion (ck_aggr
);
1027 c
->user_conv_p
= true;
1028 c
->check_narrowing
= true;
1033 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
1034 array type, if such a conversion is possible. */
1037 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
1040 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1041 tree elttype
= TREE_TYPE (type
);
1046 enum conversion_rank rank
= cr_exact
;
1048 /* We might need to propagate the size from the element to the array. */
1049 complete_type (type
);
1051 if (TYPE_DOMAIN (type
)
1052 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
1054 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
1059 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1061 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1064 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1065 false, flags
, complain
);
1069 if (sub
->rank
> rank
)
1071 if (sub
->user_conv_p
)
1077 c
= alloc_conversion (ck_aggr
);
1080 c
->user_conv_p
= user
;
1086 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1087 complex type, if such a conversion is possible. */
1090 build_complex_conv (tree type
, tree ctor
, int flags
,
1091 tsubst_flags_t complain
)
1094 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1095 tree elttype
= TREE_TYPE (type
);
1100 enum conversion_rank rank
= cr_exact
;
1105 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1107 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1110 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1111 false, flags
, complain
);
1115 if (sub
->rank
> rank
)
1117 if (sub
->user_conv_p
)
1123 c
= alloc_conversion (ck_aggr
);
1126 c
->user_conv_p
= user
;
1132 /* Build a representation of the identity conversion from EXPR to
1133 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1136 build_identity_conv (tree type
, tree expr
)
1140 c
= alloc_conversion (ck_identity
);
1147 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1148 were multiple user-defined conversions to accomplish the job.
1149 Build a conversion that indicates that ambiguity. */
1152 build_ambiguous_conv (tree type
, tree expr
)
1156 c
= alloc_conversion (ck_ambig
);
1164 strip_top_quals (tree t
)
1166 if (TREE_CODE (t
) == ARRAY_TYPE
)
1168 return cp_build_qualified_type (t
, 0);
1171 /* Returns the standard conversion path (see [conv]) from type FROM to type
1172 TO, if any. For proper handling of null pointer constants, you must
1173 also pass the expression EXPR to convert from. If C_CAST_P is true,
1174 this conversion is coming from a C-style cast. */
1177 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1178 int flags
, tsubst_flags_t complain
)
1180 enum tree_code fcode
, tcode
;
1182 bool fromref
= false;
1185 to
= non_reference (to
);
1186 if (TYPE_REF_P (from
))
1189 from
= TREE_TYPE (from
);
1192 to
= strip_top_quals (to
);
1193 from
= strip_top_quals (from
);
1195 if (expr
&& type_unknown_p (expr
))
1197 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1199 tsubst_flags_t tflags
= tf_conv
;
1200 expr
= instantiate_type (to
, expr
, tflags
);
1201 if (expr
== error_mark_node
)
1203 from
= TREE_TYPE (expr
);
1205 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1207 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1208 expr
= resolve_nondeduced_context (expr
, complain
);
1209 from
= TREE_TYPE (expr
);
1213 fcode
= TREE_CODE (from
);
1214 tcode
= TREE_CODE (to
);
1216 conv
= build_identity_conv (from
, expr
);
1217 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1219 from
= type_decays_to (from
);
1220 fcode
= TREE_CODE (from
);
1221 /* Tell convert_like_real that we're using the address. */
1222 conv
->rvaluedness_matches_p
= true;
1223 conv
= build_conv (ck_lvalue
, from
, conv
);
1225 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1226 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1227 express the copy constructor call required by copy-initialization. */
1228 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1233 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1236 from
= strip_top_quals (bitfield_type
);
1237 fcode
= TREE_CODE (from
);
1240 conv
= build_conv (ck_rvalue
, from
, conv
);
1241 if (flags
& LOOKUP_PREFER_RVALUE
)
1242 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1243 conv
->rvaluedness_matches_p
= true;
1246 /* Allow conversion between `__complex__' data types. */
1247 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1249 /* The standard conversion sequence to convert FROM to TO is
1250 the standard conversion sequence to perform componentwise
1252 conversion
*part_conv
= standard_conversion
1253 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1258 conv
= build_conv (part_conv
->kind
, to
, conv
);
1259 conv
->rank
= part_conv
->rank
;
1267 if (same_type_p (from
, to
))
1269 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1270 conv
->type
= qualified_to
;
1275 A null pointer constant can be converted to a pointer type; ... A
1276 null pointer constant of integral type can be converted to an
1277 rvalue of type std::nullptr_t. */
1278 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1279 || NULLPTR_TYPE_P (to
))
1280 && ((expr
&& null_ptr_cst_p (expr
))
1281 || NULLPTR_TYPE_P (from
)))
1282 conv
= build_conv (ck_std
, to
, conv
);
1283 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1284 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1286 /* For backwards brain damage compatibility, allow interconversion of
1287 pointers and integers with a pedwarn. */
1288 conv
= build_conv (ck_std
, to
, conv
);
1291 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1293 /* For backwards brain damage compatibility, allow interconversion of
1294 enums and integers with a pedwarn. */
1295 conv
= build_conv (ck_std
, to
, conv
);
1298 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1299 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1304 if (tcode
== POINTER_TYPE
)
1306 to_pointee
= TREE_TYPE (to
);
1307 from_pointee
= TREE_TYPE (from
);
1309 /* Since this is the target of a pointer, it can't have function
1310 qualifiers, so any TYPE_QUALS must be for attributes const or
1311 noreturn. Strip them. */
1312 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1313 && TYPE_QUALS (to_pointee
))
1314 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1315 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1316 && TYPE_QUALS (from_pointee
))
1317 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1321 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1322 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1325 if (tcode
== POINTER_TYPE
1326 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1329 else if (VOID_TYPE_P (to_pointee
)
1330 && !TYPE_PTRDATAMEM_P (from
)
1331 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1333 tree nfrom
= TREE_TYPE (from
);
1334 /* Don't try to apply restrict to void. */
1335 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1336 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1337 from
= build_pointer_type (from_pointee
);
1338 conv
= build_conv (ck_ptr
, from
, conv
);
1340 else if (TYPE_PTRDATAMEM_P (from
))
1342 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1343 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1345 if (same_type_p (fbase
, tbase
))
1346 /* No base conversion needed. */;
1347 else if (DERIVED_FROM_P (fbase
, tbase
)
1348 && (same_type_ignoring_top_level_qualifiers_p
1349 (from_pointee
, to_pointee
)))
1351 from
= build_ptrmem_type (tbase
, from_pointee
);
1352 conv
= build_conv (ck_pmem
, from
, conv
);
1357 else if (CLASS_TYPE_P (from_pointee
)
1358 && CLASS_TYPE_P (to_pointee
)
1361 An rvalue of type "pointer to cv D," where D is a
1362 class type, can be converted to an rvalue of type
1363 "pointer to cv B," where B is a base class (clause
1364 _class.derived_) of D. If B is an inaccessible
1365 (clause _class.access_) or ambiguous
1366 (_class.member.lookup_) base class of D, a program
1367 that necessitates this conversion is ill-formed.
1368 Therefore, we use DERIVED_FROM_P, and do not check
1369 access or uniqueness. */
1370 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1373 = cp_build_qualified_type (to_pointee
,
1374 cp_type_quals (from_pointee
));
1375 from
= build_pointer_type (from_pointee
);
1376 conv
= build_conv (ck_ptr
, from
, conv
);
1377 conv
->base_p
= true;
1380 if (same_type_p (from
, to
))
1382 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1383 /* In a C-style cast, we ignore CV-qualification because we
1384 are allowed to perform a static_cast followed by a
1386 conv
= build_conv (ck_qual
, to
, conv
);
1387 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1388 conv
= build_conv (ck_qual
, to
, conv
);
1389 else if (expr
&& string_conv_p (to
, expr
, 0))
1390 /* converting from string constant to char *. */
1391 conv
= build_conv (ck_qual
, to
, conv
);
1392 else if (fnptr_conv_p (to
, from
))
1393 conv
= build_conv (ck_fnptr
, to
, conv
);
1394 /* Allow conversions among compatible ObjC pointer types (base
1395 conversions have been already handled above). */
1396 else if (c_dialect_objc ()
1397 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1398 conv
= build_conv (ck_ptr
, to
, conv
);
1399 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1401 conv
= build_conv (ck_ptr
, to
, conv
);
1409 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1411 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1412 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1413 tree fbase
= class_of_this_parm (fromfn
);
1414 tree tbase
= class_of_this_parm (tofn
);
1416 if (!DERIVED_FROM_P (fbase
, tbase
))
1419 tree fstat
= static_fn_type (fromfn
);
1420 tree tstat
= static_fn_type (tofn
);
1421 if (same_type_p (tstat
, fstat
)
1422 || fnptr_conv_p (tstat
, fstat
))
1427 if (!same_type_p (fbase
, tbase
))
1429 from
= build_memfn_type (fstat
,
1431 cp_type_quals (tbase
),
1432 type_memfn_rqual (tofn
));
1433 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1434 conv
= build_conv (ck_pmem
, from
, conv
);
1435 conv
->base_p
= true;
1437 if (fnptr_conv_p (tstat
, fstat
))
1438 conv
= build_conv (ck_fnptr
, to
, conv
);
1440 else if (tcode
== BOOLEAN_TYPE
)
1444 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1445 to member type can be converted to a prvalue of type bool. ...
1446 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1447 std::nullptr_t can be converted to a prvalue of type bool; */
1448 if (ARITHMETIC_TYPE_P (from
)
1449 || UNSCOPED_ENUM_P (from
)
1450 || fcode
== POINTER_TYPE
1451 || TYPE_PTRMEM_P (from
)
1452 || NULLPTR_TYPE_P (from
))
1454 conv
= build_conv (ck_std
, to
, conv
);
1455 if (fcode
== POINTER_TYPE
1456 || TYPE_PTRDATAMEM_P (from
)
1457 || (TYPE_PTRMEMFUNC_P (from
)
1458 && conv
->rank
< cr_pbool
)
1459 || NULLPTR_TYPE_P (from
))
1460 conv
->rank
= cr_pbool
;
1461 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1463 if (flags
& LOOKUP_NO_NARROWING
)
1464 conv
->check_narrowing
= true;
1470 /* We don't check for ENUMERAL_TYPE here because there are no standard
1471 conversions to enum type. */
1472 /* As an extension, allow conversion to complex type. */
1473 else if (ARITHMETIC_TYPE_P (to
))
1475 if (! (INTEGRAL_CODE_P (fcode
)
1476 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1477 || SCOPED_ENUM_P (from
))
1480 /* If we're parsing an enum with no fixed underlying type, we're
1481 dealing with an incomplete type, which renders the conversion
1483 if (!COMPLETE_TYPE_P (from
))
1486 conv
= build_conv (ck_std
, to
, conv
);
1488 /* Give this a better rank if it's a promotion. */
1489 if (same_type_p (to
, type_promotes_to (from
))
1490 && next_conversion (conv
)->rank
<= cr_promotion
)
1491 conv
->rank
= cr_promotion
;
1493 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1494 && vector_types_convertible_p (from
, to
, false))
1495 return build_conv (ck_std
, to
, conv
);
1496 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1497 && is_properly_derived_from (from
, to
))
1499 if (conv
->kind
== ck_rvalue
)
1500 conv
= next_conversion (conv
);
1501 conv
= build_conv (ck_base
, to
, conv
);
1502 /* The derived-to-base conversion indicates the initialization
1503 of a parameter with base type from an object of a derived
1504 type. A temporary object is created to hold the result of
1505 the conversion unless we're binding directly to a reference. */
1506 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1507 if (flags
& LOOKUP_PREFER_RVALUE
)
1508 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1509 conv
->rvaluedness_matches_p
= true;
1514 if (flags
& LOOKUP_NO_NARROWING
)
1515 conv
->check_narrowing
= true;
1520 /* Returns nonzero if T1 is reference-related to T2. */
1523 reference_related_p (tree t1
, tree t2
)
1525 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1528 t1
= TYPE_MAIN_VARIANT (t1
);
1529 t2
= TYPE_MAIN_VARIANT (t2
);
1533 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1534 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1536 return (same_type_p (t1
, t2
)
1537 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1538 && DERIVED_FROM_P (t1
, t2
)));
1541 /* Returns nonzero if T1 is reference-compatible with T2. */
1544 reference_compatible_p (tree t1
, tree t2
)
1548 "cv1 T1" is reference compatible with "cv2 T2" if
1549 * T1 is reference-related to T2 or
1550 * T2 is "noexcept function" and T1 is "function", where the
1551 function types are otherwise the same,
1552 and cv1 is the same cv-qualification as, or greater cv-qualification
1554 return ((reference_related_p (t1
, t2
)
1555 || fnptr_conv_p (t1
, t2
))
1556 && at_least_as_qualified_p (t1
, t2
));
1559 /* A reference of the indicated TYPE is being bound directly to the
1560 expression represented by the implicit conversion sequence CONV.
1561 Return a conversion sequence for this binding. */
1564 direct_reference_binding (tree type
, conversion
*conv
)
1568 gcc_assert (TYPE_REF_P (type
));
1569 gcc_assert (!TYPE_REF_P (conv
->type
));
1571 t
= TREE_TYPE (type
);
1573 if (conv
->kind
== ck_identity
)
1574 /* Mark the identity conv as to not decay to rvalue. */
1575 conv
->rvaluedness_matches_p
= true;
1579 When a parameter of reference type binds directly
1580 (_dcl.init.ref_) to an argument expression, the implicit
1581 conversion sequence is the identity conversion, unless the
1582 argument expression has a type that is a derived class of the
1583 parameter type, in which case the implicit conversion sequence is
1584 a derived-to-base Conversion.
1586 If the parameter binds directly to the result of applying a
1587 conversion function to the argument expression, the implicit
1588 conversion sequence is a user-defined conversion sequence
1589 (_over.ics.user_), with the second standard conversion sequence
1590 either an identity conversion or, if the conversion function
1591 returns an entity of a type that is a derived class of the
1592 parameter type, a derived-to-base conversion. */
1593 if (is_properly_derived_from (conv
->type
, t
))
1595 /* Represent the derived-to-base conversion. */
1596 conv
= build_conv (ck_base
, t
, conv
);
1597 /* We will actually be binding to the base-class subobject in
1598 the derived class, so we mark this conversion appropriately.
1599 That way, convert_like knows not to generate a temporary. */
1600 conv
->need_temporary_p
= false;
1603 return build_conv (ck_ref_bind
, type
, conv
);
1606 /* Returns the conversion path from type FROM to reference type TO for
1607 purposes of reference binding. For lvalue binding, either pass a
1608 reference type to FROM or an lvalue expression to EXPR. If the
1609 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1610 the conversion returned. If C_CAST_P is true, this
1611 conversion is coming from a C-style cast. */
1614 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1615 tsubst_flags_t complain
)
1617 conversion
*conv
= NULL
;
1618 tree to
= TREE_TYPE (rto
);
1623 cp_lvalue_kind gl_kind
;
1626 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1628 expr
= instantiate_type (to
, expr
, tf_none
);
1629 if (expr
== error_mark_node
)
1631 from
= TREE_TYPE (expr
);
1634 bool copy_list_init
= false;
1635 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1637 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1638 /* DR 1288: Otherwise, if the initializer list has a single element
1639 of type E and ... [T's] referenced type is reference-related to E,
1640 the object or reference is initialized from that element... */
1641 if (CONSTRUCTOR_NELTS (expr
) == 1)
1643 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1644 if (error_operand_p (elt
))
1646 tree etype
= TREE_TYPE (elt
);
1647 if (reference_related_p (to
, etype
))
1654 /* Otherwise, if T is a reference type, a prvalue temporary of the type
1655 referenced by T is copy-list-initialized, and the reference is bound
1656 to that temporary. */
1657 copy_list_init
= true;
1661 if (TYPE_REF_P (from
))
1663 from
= TREE_TYPE (from
);
1664 if (!TYPE_REF_IS_RVALUE (rfrom
)
1665 || TREE_CODE (from
) == FUNCTION_TYPE
)
1666 gl_kind
= clk_ordinary
;
1668 gl_kind
= clk_rvalueref
;
1671 gl_kind
= lvalue_kind (expr
);
1672 else if (CLASS_TYPE_P (from
)
1673 || TREE_CODE (from
) == ARRAY_TYPE
)
1674 gl_kind
= clk_class
;
1678 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1679 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1680 && (gl_kind
& clk_class
))
1683 /* Same mask as real_lvalue_p. */
1684 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1687 if ((gl_kind
& clk_bitfield
) != 0)
1688 tfrom
= unlowered_expr_type (expr
);
1690 /* Figure out whether or not the types are reference-related and
1691 reference compatible. We have to do this after stripping
1692 references from FROM. */
1693 related_p
= reference_related_p (to
, tfrom
);
1694 /* If this is a C cast, first convert to an appropriately qualified
1695 type, so that we can later do a const_cast to the desired type. */
1696 if (related_p
&& c_cast_p
1697 && !at_least_as_qualified_p (to
, tfrom
))
1698 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1699 compatible_p
= reference_compatible_p (to
, tfrom
);
1701 /* Directly bind reference when target expression's type is compatible with
1702 the reference and expression is an lvalue. In DR391, the wording in
1703 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1704 const and rvalue references to rvalues of compatible class type.
1705 We should also do direct bindings for non-class xvalues. */
1706 if ((related_p
|| compatible_p
) && gl_kind
)
1710 If the initializer expression
1712 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1713 is reference-compatible with "cv2 T2,"
1715 the reference is bound directly to the initializer expression
1719 If the initializer expression is an rvalue, with T2 a class type,
1720 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1721 is bound to the object represented by the rvalue or to a sub-object
1722 within that object. */
1724 conv
= build_identity_conv (tfrom
, expr
);
1725 conv
= direct_reference_binding (rto
, conv
);
1727 if (TYPE_REF_P (rfrom
))
1728 /* Handle rvalue reference to function properly. */
1729 conv
->rvaluedness_matches_p
1730 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1732 conv
->rvaluedness_matches_p
1733 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1735 if ((gl_kind
& clk_bitfield
) != 0
1736 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1737 /* For the purposes of overload resolution, we ignore the fact
1738 this expression is a bitfield or packed field. (In particular,
1739 [over.ics.ref] says specifically that a function with a
1740 non-const reference parameter is viable even if the
1741 argument is a bitfield.)
1743 However, when we actually call the function we must create
1744 a temporary to which to bind the reference. If the
1745 reference is volatile, or isn't const, then we cannot make
1746 a temporary, so we just issue an error when the conversion
1748 conv
->need_temporary_p
= true;
1750 /* Don't allow binding of lvalues (other than function lvalues) to
1751 rvalue references. */
1752 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1753 && TREE_CODE (to
) != FUNCTION_TYPE
)
1756 /* Nor the reverse. */
1757 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1758 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1759 || (flags
& LOOKUP_NO_RVAL_BIND
))
1760 && TREE_CODE (to
) != FUNCTION_TYPE
)
1768 /* [class.conv.fct] A conversion function is never used to convert a
1769 (possibly cv-qualified) object to the (possibly cv-qualified) same
1770 object type (or a reference to it), to a (possibly cv-qualified) base
1771 class of that type (or a reference to it).... */
1772 else if (CLASS_TYPE_P (from
) && !related_p
1773 && !(flags
& LOOKUP_NO_CONVERSION
))
1777 If the initializer expression
1779 -- has a class type (i.e., T2 is a class type) can be
1780 implicitly converted to an lvalue of type "cv3 T3," where
1781 "cv1 T1" is reference-compatible with "cv3 T3". (this
1782 conversion is selected by enumerating the applicable
1783 conversion functions (_over.match.ref_) and choosing the
1784 best one through overload resolution. (_over.match_).
1786 the reference is bound to the lvalue result of the conversion
1787 in the second case. */
1788 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1791 return cand
->second_conv
;
1794 /* From this point on, we conceptually need temporaries, even if we
1795 elide them. Only the cases above are "direct bindings". */
1796 if (flags
& LOOKUP_NO_TEMP_BIND
)
1801 When a parameter of reference type is not bound directly to an
1802 argument expression, the conversion sequence is the one required
1803 to convert the argument expression to the underlying type of the
1804 reference according to _over.best.ics_. Conceptually, this
1805 conversion sequence corresponds to copy-initializing a temporary
1806 of the underlying type with the argument expression. Any
1807 difference in top-level cv-qualification is subsumed by the
1808 initialization itself and does not constitute a conversion. */
1812 Otherwise, the reference shall be an lvalue reference to a
1813 non-volatile const type, or the reference shall be an rvalue
1816 We try below to treat this as a bad conversion to improve diagnostics,
1817 but if TO is an incomplete class, we need to reject this conversion
1818 now to avoid unnecessary instantiation. */
1819 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1820 && !COMPLETE_TYPE_P (to
))
1823 /* We're generating a temporary now, but don't bind any more in the
1824 conversion (specifically, don't slice the temporary returned by a
1825 conversion operator). */
1826 flags
|= LOOKUP_NO_TEMP_BIND
;
1828 /* Core issue 899: When [copy-]initializing a temporary to be bound
1829 to the first parameter of a copy constructor (12.8) called with
1830 a single argument in the context of direct-initialization,
1831 explicit conversion functions are also considered.
1833 So don't set LOOKUP_ONLYCONVERTING in that case. */
1834 if (!(flags
& LOOKUP_COPY_PARM
))
1835 flags
|= LOOKUP_ONLYCONVERTING
;
1838 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1843 if (conv
->user_conv_p
)
1846 /* Remember this was copy-list-initialization. */
1847 conv
->need_temporary_p
= true;
1849 /* If initializing the temporary used a conversion function,
1850 recalculate the second conversion sequence. */
1851 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1852 if (t
->kind
== ck_user
1853 && DECL_CONV_FN_P (t
->cand
->fn
))
1855 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1856 /* A prvalue of non-class type is cv-unqualified. */
1857 if (!TYPE_REF_P (ftype
) && !CLASS_TYPE_P (ftype
))
1858 ftype
= cv_unqualified (ftype
);
1859 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1860 conversion
*new_second
1861 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1865 return merge_conversion_sequences (t
, new_second
);
1869 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1870 /* This reference binding, unlike those above, requires the
1871 creation of a temporary. */
1872 conv
->need_temporary_p
= true;
1873 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1877 Otherwise, the reference shall be an lvalue reference to a
1878 non-volatile const type, or the reference shall be an rvalue
1880 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1885 Otherwise, a temporary of type "cv1 T1" is created and
1886 initialized from the initializer expression using the rules for a
1887 non-reference copy initialization. If T1 is reference-related to
1888 T2, cv1 must be the same cv-qualification as, or greater
1889 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1890 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1896 /* Returns the implicit conversion sequence (see [over.ics]) from type
1897 FROM to type TO. The optional expression EXPR may affect the
1898 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1899 true, this conversion is coming from a C-style cast. */
1902 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1903 int flags
, tsubst_flags_t complain
)
1907 if (from
== error_mark_node
|| to
== error_mark_node
1908 || expr
== error_mark_node
)
1911 /* Other flags only apply to the primary function in overload
1912 resolution, or after we've chosen one. */
1913 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1914 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1915 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1917 /* FIXME: actually we don't want warnings either, but we can't just
1918 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1919 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1920 We really ought not to issue that warning until we've committed
1921 to that conversion. */
1922 complain
&= ~tf_error
;
1924 /* Call reshape_init early to remove redundant braces. */
1925 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1926 && CLASS_TYPE_P (to
)
1927 && COMPLETE_TYPE_P (complete_type (to
))
1928 && !CLASSTYPE_NON_AGGREGATE (to
))
1930 expr
= reshape_init (to
, expr
, complain
);
1931 if (expr
== error_mark_node
)
1933 from
= TREE_TYPE (expr
);
1936 if (TYPE_REF_P (to
))
1937 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1939 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1944 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1946 if (is_std_init_list (to
) && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1947 return build_list_conv (to
, expr
, flags
, complain
);
1949 /* As an extension, allow list-initialization of _Complex. */
1950 if (TREE_CODE (to
) == COMPLEX_TYPE
1951 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1953 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1958 /* Allow conversion from an initializer-list with one element to a
1960 if (SCALAR_TYPE_P (to
))
1962 int nelts
= CONSTRUCTOR_NELTS (expr
);
1966 elt
= build_value_init (to
, tf_none
);
1967 else if (nelts
== 1 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1968 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1970 elt
= error_mark_node
;
1972 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1973 c_cast_p
, flags
, complain
);
1976 conv
->check_narrowing
= true;
1977 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1978 /* Too many levels of braces, i.e. '{{1}}'. */
1983 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1984 return build_array_conv (to
, expr
, flags
, complain
);
1987 if (expr
!= NULL_TREE
1988 && (MAYBE_CLASS_TYPE_P (from
)
1989 || MAYBE_CLASS_TYPE_P (to
))
1990 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1992 struct z_candidate
*cand
;
1994 if (CLASS_TYPE_P (to
)
1995 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1996 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1997 return build_aggr_conv (to
, expr
, flags
, complain
);
1999 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
2002 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
2003 && CONSTRUCTOR_NELTS (expr
) == 1
2004 && !is_list_ctor (cand
->fn
))
2006 /* "If C is not an initializer-list constructor and the
2007 initializer list has a single element of type cv U, where U is
2008 X or a class derived from X, the implicit conversion sequence
2009 has Exact Match rank if U is X, or Conversion rank if U is
2011 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
2012 tree elttype
= TREE_TYPE (elt
);
2013 if (reference_related_p (to
, elttype
))
2014 return implicit_conversion (to
, elttype
, elt
,
2015 c_cast_p
, flags
, complain
);
2017 conv
= cand
->second_conv
;
2020 /* We used to try to bind a reference to a temporary here, but that
2021 is now handled after the recursive call to this function at the end
2022 of reference_binding. */
2029 /* Like implicit_conversion, but return NULL if the conversion is bad.
2031 This is not static so that check_non_deducible_conversion can call it within
2032 add_template_candidate_real as part of overload resolution; it should not be
2033 called outside of overload resolution. */
2036 good_conversion (tree to
, tree from
, tree expr
,
2037 int flags
, tsubst_flags_t complain
)
2039 conversion
*c
= implicit_conversion (to
, from
, expr
, /*cast*/false,
2046 /* Add a new entry to the list of candidates. Used by the add_*_candidate
2047 functions. ARGS will not be changed until a single candidate is
2050 static struct z_candidate
*
2051 add_candidate (struct z_candidate
**candidates
,
2052 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
2053 size_t num_convs
, conversion
**convs
,
2054 tree access_path
, tree conversion_path
,
2055 int viable
, struct rejection_reason
*reason
,
2058 struct z_candidate
*cand
= (struct z_candidate
*)
2059 conversion_obstack_alloc (sizeof (struct z_candidate
));
2062 cand
->first_arg
= first_arg
;
2064 cand
->convs
= convs
;
2065 cand
->num_convs
= num_convs
;
2066 cand
->access_path
= access_path
;
2067 cand
->conversion_path
= conversion_path
;
2068 cand
->viable
= viable
;
2069 cand
->reason
= reason
;
2070 cand
->next
= *candidates
;
2071 cand
->flags
= flags
;
2077 /* Return the number of remaining arguments in the parameter list
2078 beginning with ARG. */
2081 remaining_arguments (tree arg
)
2085 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
2086 arg
= TREE_CHAIN (arg
))
2092 /* [over.match.copy]: When initializing a temporary object (12.2) to be bound
2093 to the first parameter of a constructor where the parameter is of type
2094 "reference to possibly cv-qualified T" and the constructor is called with a
2095 single argument in the context of direct-initialization of an object of type
2096 "cv2 T", explicit conversion functions are also considered.
2098 So set LOOKUP_COPY_PARM to let reference_binding know that
2099 it's being called in that context. */
2102 conv_flags (int i
, int nargs
, tree fn
, tree arg
, int flags
)
2106 if (i
== 0 && nargs
== 1 && DECL_CONSTRUCTOR_P (fn
)
2107 && (t
= FUNCTION_FIRST_USER_PARMTYPE (fn
))
2108 && (same_type_ignoring_top_level_qualifiers_p
2109 (non_reference (TREE_VALUE (t
)), DECL_CONTEXT (fn
))))
2111 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2112 lflags
|= LOOKUP_COPY_PARM
;
2113 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2114 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2115 lflags
|= LOOKUP_NO_CONVERSION
;
2118 lflags
|= LOOKUP_ONLYCONVERTING
;
2123 /* Create an overload candidate for the function or method FN called
2124 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
2125 FLAGS is passed on to implicit_conversion.
2127 This does not change ARGS.
2129 CTYPE, if non-NULL, is the type we want to pretend this function
2130 comes from for purposes of overload resolution. */
2132 static struct z_candidate
*
2133 add_function_candidate (struct z_candidate
**candidates
,
2134 tree fn
, tree ctype
, tree first_arg
,
2135 const vec
<tree
, va_gc
> *args
, tree access_path
,
2136 tree conversion_path
, int flags
,
2138 tsubst_flags_t complain
)
2140 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2143 tree orig_first_arg
= first_arg
;
2146 struct rejection_reason
*reason
= NULL
;
2148 /* At this point we should not see any functions which haven't been
2149 explicitly declared, except for friend functions which will have
2150 been found using argument dependent lookup. */
2151 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2153 /* The `this', `in_chrg' and VTT arguments to constructors are not
2154 considered in overload resolution. */
2155 if (DECL_CONSTRUCTOR_P (fn
))
2157 if (ctor_omit_inherited_parms (fn
))
2158 /* Bring back parameters omitted from an inherited ctor. */
2159 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2161 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2162 skip
= num_artificial_parms_for (fn
);
2163 if (skip
> 0 && first_arg
!= NULL_TREE
)
2166 first_arg
= NULL_TREE
;
2172 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2174 convs
= alloc_conversions (len
);
2176 /* 13.3.2 - Viable functions [over.match.viable]
2177 First, to be a viable function, a candidate function shall have enough
2178 parameters to agree in number with the arguments in the list.
2180 We need to check this first; otherwise, checking the ICSes might cause
2181 us to produce an ill-formed template instantiation. */
2183 parmnode
= parmlist
;
2184 for (i
= 0; i
< len
; ++i
)
2186 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2188 parmnode
= TREE_CHAIN (parmnode
);
2191 if ((i
< len
&& parmnode
)
2192 || !sufficient_parms_p (parmnode
))
2194 int remaining
= remaining_arguments (parmnode
);
2196 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2199 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2200 parameter of type "reference to cv C" (including such a constructor
2201 instantiated from a template) is excluded from the set of candidate
2202 functions when used to construct an object of type D with an argument list
2203 containing a single argument if C is reference-related to D. */
2204 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2205 && flag_new_inheriting_ctors
2206 && DECL_INHERITED_CTOR (fn
))
2208 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2209 tree dtype
= DECL_CONTEXT (fn
);
2210 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2211 if (reference_related_p (ptype
, dtype
)
2212 && reference_related_p (btype
, ptype
))
2215 reason
= inherited_ctor_rejection ();
2219 /* Second, for a function to be viable, its constraints must be
2221 if (flag_concepts
&& viable
2222 && !constraints_satisfied_p (fn
))
2224 reason
= constraint_failure (fn
);
2228 /* When looking for a function from a subobject from an implicit
2229 copy/move constructor/operator=, don't consider anything that takes (a
2230 reference to) an unrelated type. See c++/44909 and core 1092. */
2231 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2233 if (DECL_CONSTRUCTOR_P (fn
))
2235 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2236 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2242 parmnode
= chain_index (i
-1, parmlist
);
2243 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2248 /* This only applies at the top level. */
2249 flags
&= ~LOOKUP_DEFAULTED
;
2255 /* Third, for F to be a viable function, there shall exist for each
2256 argument an implicit conversion sequence that converts that argument
2257 to the corresponding parameter of F. */
2259 parmnode
= parmlist
;
2261 for (i
= 0; i
< len
; ++i
)
2263 tree argtype
, to_type
;
2268 if (parmnode
== void_list_node
)
2273 /* Already set during deduction. */
2274 parmnode
= TREE_CHAIN (parmnode
);
2278 if (i
== 0 && first_arg
!= NULL_TREE
)
2281 arg
= CONST_CAST_TREE (
2282 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2283 argtype
= lvalue_type (arg
);
2285 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2286 && ! DECL_CONSTRUCTOR_P (fn
));
2290 tree parmtype
= TREE_VALUE (parmnode
);
2292 parmnode
= TREE_CHAIN (parmnode
);
2294 /* The type of the implicit object parameter ('this') for
2295 overload resolution is not always the same as for the
2296 function itself; conversion functions are considered to
2297 be members of the class being converted, and functions
2298 introduced by a using-declaration are considered to be
2299 members of the class that uses them.
2301 Since build_over_call ignores the ICS for the `this'
2302 parameter, we can just change the parm type. */
2303 if (ctype
&& is_this
)
2305 parmtype
= cp_build_qualified_type
2306 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2307 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2309 /* If the function has a ref-qualifier, the implicit
2310 object parameter has reference type. */
2311 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2312 parmtype
= cp_build_reference_type (parmtype
, rv
);
2313 /* The special handling of 'this' conversions in compare_ics
2314 does not apply if there is a ref-qualifier. */
2319 parmtype
= build_pointer_type (parmtype
);
2320 /* We don't use build_this here because we don't want to
2321 capture the object argument until we've chosen a
2322 non-static member function. */
2323 arg
= build_address (arg
);
2324 argtype
= lvalue_type (arg
);
2328 int lflags
= conv_flags (i
, len
-skip
, fn
, arg
, flags
);
2330 t
= implicit_conversion (parmtype
, argtype
, arg
,
2331 /*c_cast_p=*/false, lflags
, complain
);
2336 t
= build_identity_conv (argtype
, arg
);
2337 t
->ellipsis_p
= true;
2348 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
,
2349 EXPR_LOCATION (arg
));
2356 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
,
2357 EXPR_LOCATION (arg
));
2363 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2364 access_path
, conversion_path
, viable
, reason
, flags
);
2367 /* Create an overload candidate for the conversion function FN which will
2368 be invoked for expression OBJ, producing a pointer-to-function which
2369 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2370 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2371 passed on to implicit_conversion.
2373 Actually, we don't really care about FN; we care about the type it
2374 converts to. There may be multiple conversion functions that will
2375 convert to that type, and we rely on build_user_type_conversion_1 to
2376 choose the best one; so when we create our candidate, we record the type
2377 instead of the function. */
2379 static struct z_candidate
*
2380 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2381 const vec
<tree
, va_gc
> *arglist
,
2382 tree access_path
, tree conversion_path
,
2383 tsubst_flags_t complain
)
2385 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2386 int i
, len
, viable
, flags
;
2387 tree parmlist
, parmnode
;
2389 struct rejection_reason
*reason
;
2391 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2392 parmlist
= TREE_TYPE (parmlist
);
2393 parmlist
= TYPE_ARG_TYPES (parmlist
);
2395 len
= vec_safe_length (arglist
) + 1;
2396 convs
= alloc_conversions (len
);
2397 parmnode
= parmlist
;
2399 flags
= LOOKUP_IMPLICIT
;
2402 /* Don't bother looking up the same type twice. */
2403 if (*candidates
&& (*candidates
)->fn
== totype
)
2406 for (i
= 0; i
< len
; ++i
)
2408 tree arg
, argtype
, convert_type
= NULL_TREE
;
2414 arg
= (*arglist
)[i
- 1];
2415 argtype
= lvalue_type (arg
);
2419 t
= build_identity_conv (argtype
, NULL_TREE
);
2420 t
= build_conv (ck_user
, totype
, t
);
2421 /* Leave the 'cand' field null; we'll figure out the conversion in
2422 convert_like_real if this candidate is chosen. */
2423 convert_type
= totype
;
2425 else if (parmnode
== void_list_node
)
2429 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2430 /*c_cast_p=*/false, flags
, complain
);
2431 convert_type
= TREE_VALUE (parmnode
);
2435 t
= build_identity_conv (argtype
, arg
);
2436 t
->ellipsis_p
= true;
2437 convert_type
= argtype
;
2447 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
,
2448 EXPR_LOCATION (arg
));
2455 parmnode
= TREE_CHAIN (parmnode
);
2459 || ! sufficient_parms_p (parmnode
))
2461 int remaining
= remaining_arguments (parmnode
);
2463 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2466 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2467 access_path
, conversion_path
, viable
, reason
, flags
);
2471 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2472 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2473 int flags
, tsubst_flags_t complain
)
2480 struct rejection_reason
*reason
= NULL
;
2485 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2486 convs
= alloc_conversions (num_convs
);
2488 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2489 conversion ops are allowed. We handle that here by just checking for
2490 boolean_type_node because other operators don't ask for it. COND_EXPR
2491 also does contextual conversion to bool for the first operand, but we
2492 handle that in build_conditional_expr, and type1 here is operand 2. */
2493 if (type1
!= boolean_type_node
)
2494 flags
|= LOOKUP_ONLYCONVERTING
;
2496 for (i
= 0; i
< 2; ++i
)
2501 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2502 /*c_cast_p=*/false, flags
, complain
);
2506 /* We need something for printing the candidate. */
2507 t
= build_identity_conv (types
[i
], NULL_TREE
);
2508 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2509 types
[i
], EXPR_LOCATION (args
[i
]));
2514 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2516 EXPR_LOCATION (args
[i
]));
2521 /* For COND_EXPR we rearranged the arguments; undo that now. */
2524 convs
[2] = convs
[1];
2525 convs
[1] = convs
[0];
2526 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2527 /*c_cast_p=*/false, flags
,
2534 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2536 EXPR_LOCATION (args
[2]));
2540 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2542 /*access_path=*/NULL_TREE
,
2543 /*conversion_path=*/NULL_TREE
,
2544 viable
, reason
, flags
);
2548 is_complete (tree t
)
2550 return COMPLETE_TYPE_P (complete_type (t
));
2553 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2556 promoted_arithmetic_type_p (tree type
)
2560 In this section, the term promoted integral type is used to refer
2561 to those integral types which are preserved by integral promotion
2562 (including e.g. int and long but excluding e.g. char).
2563 Similarly, the term promoted arithmetic type refers to promoted
2564 integral types plus floating types. */
2565 return ((CP_INTEGRAL_TYPE_P (type
)
2566 && same_type_p (type_promotes_to (type
), type
))
2567 || TREE_CODE (type
) == REAL_TYPE
);
2570 /* Create any builtin operator overload candidates for the operator in
2571 question given the converted operand types TYPE1 and TYPE2. The other
2572 args are passed through from add_builtin_candidates to
2573 build_builtin_candidate.
2575 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2576 If CODE is requires candidates operands of the same type of the kind
2577 of which TYPE1 and TYPE2 are, we add both candidates
2578 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2581 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2582 enum tree_code code2
, tree fnname
, tree type1
,
2583 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2584 tsubst_flags_t complain
)
2588 case POSTINCREMENT_EXPR
:
2589 case POSTDECREMENT_EXPR
:
2590 args
[1] = integer_zero_node
;
2591 type2
= integer_type_node
;
2600 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2601 and VQ is either volatile or empty, there exist candidate operator
2602 functions of the form
2603 VQ T& operator++(VQ T&);
2604 T operator++(VQ T&, int);
2605 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2606 type other than bool, and VQ is either volatile or empty, there exist
2607 candidate operator functions of the form
2608 VQ T& operator--(VQ T&);
2609 T operator--(VQ T&, int);
2610 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2611 complete object type, and VQ is either volatile or empty, there exist
2612 candidate operator functions of the form
2613 T*VQ& operator++(T*VQ&);
2614 T*VQ& operator--(T*VQ&);
2615 T* operator++(T*VQ&, int);
2616 T* operator--(T*VQ&, int); */
2618 case POSTDECREMENT_EXPR
:
2619 case PREDECREMENT_EXPR
:
2620 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2623 case POSTINCREMENT_EXPR
:
2624 case PREINCREMENT_EXPR
:
2625 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2627 type1
= build_reference_type (type1
);
2632 /* 7 For every cv-qualified or cv-unqualified object type T, there
2633 exist candidate operator functions of the form
2637 8 For every function type T, there exist candidate operator functions of
2639 T& operator*(T*); */
2642 if (TYPE_PTR_P (type1
)
2643 && (TYPE_PTROB_P (type1
)
2644 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2648 /* 9 For every type T, there exist candidate operator functions of the form
2651 10For every promoted arithmetic type T, there exist candidate operator
2652 functions of the form
2656 case UNARY_PLUS_EXPR
: /* unary + */
2657 if (TYPE_PTR_P (type1
))
2661 if (ARITHMETIC_TYPE_P (type1
))
2665 /* 11For every promoted integral type T, there exist candidate operator
2666 functions of the form
2670 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2674 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2675 is the same type as C2 or is a derived class of C2, T is a complete
2676 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2677 there exist candidate operator functions of the form
2678 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2679 where CV12 is the union of CV1 and CV2. */
2682 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2684 tree c1
= TREE_TYPE (type1
);
2685 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2687 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2688 && (TYPE_PTRMEMFUNC_P (type2
)
2689 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2694 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2695 didate operator functions of the form
2700 bool operator<(L, R);
2701 bool operator>(L, R);
2702 bool operator<=(L, R);
2703 bool operator>=(L, R);
2704 bool operator==(L, R);
2705 bool operator!=(L, R);
2706 where LR is the result of the usual arithmetic conversions between
2709 14For every pair of types T and I, where T is a cv-qualified or cv-
2710 unqualified complete object type and I is a promoted integral type,
2711 there exist candidate operator functions of the form
2712 T* operator+(T*, I);
2713 T& operator[](T*, I);
2714 T* operator-(T*, I);
2715 T* operator+(I, T*);
2716 T& operator[](I, T*);
2718 15For every T, where T is a pointer to complete object type, there exist
2719 candidate operator functions of the form112)
2720 ptrdiff_t operator-(T, T);
2722 16For every pointer or enumeration type T, there exist candidate operator
2723 functions of the form
2724 bool operator<(T, T);
2725 bool operator>(T, T);
2726 bool operator<=(T, T);
2727 bool operator>=(T, T);
2728 bool operator==(T, T);
2729 bool operator!=(T, T);
2731 17For every pointer to member type T, there exist candidate operator
2732 functions of the form
2733 bool operator==(T, T);
2734 bool operator!=(T, T); */
2737 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2739 if (TYPE_PTROB_P (type1
)
2740 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2742 type2
= ptrdiff_type_node
;
2747 case TRUNC_DIV_EXPR
:
2748 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2754 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2755 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2757 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2762 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2774 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2776 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2778 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2779 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2781 if (TYPE_PTR_P (type1
)
2782 && null_ptr_cst_p (args
[1]))
2787 if (null_ptr_cst_p (args
[0])
2788 && TYPE_PTR_P (type2
))
2796 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2800 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2802 type1
= ptrdiff_type_node
;
2805 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2807 type2
= ptrdiff_type_node
;
2812 /* 18For every pair of promoted integral types L and R, there exist candi-
2813 date operator functions of the form
2820 where LR is the result of the usual arithmetic conversions between
2823 case TRUNC_MOD_EXPR
:
2829 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2833 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2834 type, VQ is either volatile or empty, and R is a promoted arithmetic
2835 type, there exist candidate operator functions of the form
2836 VQ L& operator=(VQ L&, R);
2837 VQ L& operator*=(VQ L&, R);
2838 VQ L& operator/=(VQ L&, R);
2839 VQ L& operator+=(VQ L&, R);
2840 VQ L& operator-=(VQ L&, R);
2842 20For every pair T, VQ), where T is any type and VQ is either volatile
2843 or empty, there exist candidate operator functions of the form
2844 T*VQ& operator=(T*VQ&, T*);
2846 21For every pair T, VQ), where T is a pointer to member type and VQ is
2847 either volatile or empty, there exist candidate operator functions of
2849 VQ T& operator=(VQ T&, T);
2851 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2852 unqualified complete object type, VQ is either volatile or empty, and
2853 I is a promoted integral type, there exist candidate operator func-
2855 T*VQ& operator+=(T*VQ&, I);
2856 T*VQ& operator-=(T*VQ&, I);
2858 23For every triple L, VQ, R), where L is an integral or enumeration
2859 type, VQ is either volatile or empty, and R is a promoted integral
2860 type, there exist candidate operator functions of the form
2862 VQ L& operator%=(VQ L&, R);
2863 VQ L& operator<<=(VQ L&, R);
2864 VQ L& operator>>=(VQ L&, R);
2865 VQ L& operator&=(VQ L&, R);
2866 VQ L& operator^=(VQ L&, R);
2867 VQ L& operator|=(VQ L&, R); */
2874 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2876 type2
= ptrdiff_type_node
;
2881 case TRUNC_DIV_EXPR
:
2882 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2886 case TRUNC_MOD_EXPR
:
2892 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2897 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2899 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2900 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2901 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2902 || ((TYPE_PTRMEMFUNC_P (type1
)
2903 || TYPE_PTR_P (type1
))
2904 && null_ptr_cst_p (args
[1])))
2914 type1
= build_reference_type (type1
);
2920 For every pair of promoted arithmetic types L and R, there
2921 exist candidate operator functions of the form
2923 LR operator?(bool, L, R);
2925 where LR is the result of the usual arithmetic conversions
2926 between types L and R.
2928 For every type T, where T is a pointer or pointer-to-member
2929 type, there exist candidate operator functions of the form T
2930 operator?(bool, T, T); */
2932 if (promoted_arithmetic_type_p (type1
)
2933 && promoted_arithmetic_type_p (type2
))
2937 /* Otherwise, the types should be pointers. */
2938 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2941 /* We don't check that the two types are the same; the logic
2942 below will actually create two candidates; one in which both
2943 parameter types are TYPE1, and one in which both parameter
2949 if (ARITHMETIC_TYPE_P (type1
))
2957 /* Make sure we don't create builtin candidates with dependent types. */
2958 bool u1
= uses_template_parms (type1
);
2959 bool u2
= type2
? uses_template_parms (type2
) : false;
2962 /* Try to recover if one of the types is non-dependent. But if
2963 there's only one type, there's nothing we can do. */
2966 /* And we lose if both are dependent. */
2969 /* Or if they have different forms. */
2970 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2979 /* If we're dealing with two pointer types or two enumeral types,
2980 we need candidates for both of them. */
2981 if (type2
&& !same_type_p (type1
, type2
)
2982 && TREE_CODE (type1
) == TREE_CODE (type2
)
2983 && (TYPE_REF_P (type1
)
2984 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2985 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2986 || TYPE_PTRMEMFUNC_P (type1
)
2987 || MAYBE_CLASS_TYPE_P (type1
)
2988 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2990 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2992 tree cptype
= composite_pointer_type (type1
, type2
,
2997 if (cptype
!= error_mark_node
)
2999 build_builtin_candidate
3000 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
3006 build_builtin_candidate
3007 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
3008 build_builtin_candidate
3009 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
3013 build_builtin_candidate
3014 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
3018 type_decays_to (tree type
)
3020 if (TREE_CODE (type
) == ARRAY_TYPE
)
3021 return build_pointer_type (TREE_TYPE (type
));
3022 if (TREE_CODE (type
) == FUNCTION_TYPE
)
3023 return build_pointer_type (type
);
3027 /* There are three conditions of builtin candidates:
3029 1) bool-taking candidates. These are the same regardless of the input.
3030 2) pointer-pair taking candidates. These are generated for each type
3031 one of the input types converts to.
3032 3) arithmetic candidates. According to the standard, we should generate
3033 all of these, but I'm trying not to...
3035 Here we generate a superset of the possible candidates for this particular
3036 case. That is a subset of the full set the standard defines, plus some
3037 other cases which the standard disallows. add_builtin_candidate will
3038 filter out the invalid set. */
3041 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
3042 enum tree_code code2
, tree fnname
, tree
*args
,
3043 int flags
, tsubst_flags_t complain
)
3047 tree type
, argtypes
[3], t
;
3048 /* TYPES[i] is the set of possible builtin-operator parameter types
3049 we will consider for the Ith argument. */
3050 vec
<tree
, va_gc
> *types
[2];
3053 for (i
= 0; i
< 3; ++i
)
3056 argtypes
[i
] = unlowered_expr_type (args
[i
]);
3058 argtypes
[i
] = NULL_TREE
;
3063 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
3064 and VQ is either volatile or empty, there exist candidate operator
3065 functions of the form
3066 VQ T& operator++(VQ T&); */
3068 case POSTINCREMENT_EXPR
:
3069 case PREINCREMENT_EXPR
:
3070 case POSTDECREMENT_EXPR
:
3071 case PREDECREMENT_EXPR
:
3076 /* 24There also exist candidate operator functions of the form
3077 bool operator!(bool);
3078 bool operator&&(bool, bool);
3079 bool operator||(bool, bool); */
3081 case TRUTH_NOT_EXPR
:
3082 build_builtin_candidate
3083 (candidates
, fnname
, boolean_type_node
,
3084 NULL_TREE
, args
, argtypes
, flags
, complain
);
3087 case TRUTH_ORIF_EXPR
:
3088 case TRUTH_ANDIF_EXPR
:
3089 build_builtin_candidate
3090 (candidates
, fnname
, boolean_type_node
,
3091 boolean_type_node
, args
, argtypes
, flags
, complain
);
3113 types
[0] = make_tree_vector ();
3114 types
[1] = make_tree_vector ();
3116 for (i
= 0; i
< 2; ++i
)
3120 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
3124 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
3127 convs
= lookup_conversions (argtypes
[i
]);
3129 if (code
== COND_EXPR
)
3131 if (lvalue_p (args
[i
]))
3132 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3134 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3140 for (; convs
; convs
= TREE_CHAIN (convs
))
3142 type
= TREE_TYPE (convs
);
3145 && (!TYPE_REF_P (type
)
3146 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3149 if (code
== COND_EXPR
&& TYPE_REF_P (type
))
3150 vec_safe_push (types
[i
], type
);
3152 type
= non_reference (type
);
3153 if (i
!= 0 || ! ref1
)
3155 type
= cv_unqualified (type_decays_to (type
));
3156 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3157 vec_safe_push (types
[i
], type
);
3158 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3159 type
= type_promotes_to (type
);
3162 if (! vec_member (type
, types
[i
]))
3163 vec_safe_push (types
[i
], type
);
3168 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3169 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3170 type
= non_reference (argtypes
[i
]);
3171 if (i
!= 0 || ! ref1
)
3173 type
= cv_unqualified (type_decays_to (type
));
3174 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3175 vec_safe_push (types
[i
], type
);
3176 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3177 type
= type_promotes_to (type
);
3179 vec_safe_push (types
[i
], type
);
3183 /* Run through the possible parameter types of both arguments,
3184 creating candidates with those parameter types. */
3185 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3190 if (!types
[1]->is_empty ())
3191 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3192 add_builtin_candidate
3193 (candidates
, code
, code2
, fnname
, t
,
3194 u
, args
, argtypes
, flags
, complain
);
3196 add_builtin_candidate
3197 (candidates
, code
, code2
, fnname
, t
,
3198 NULL_TREE
, args
, argtypes
, flags
, complain
);
3201 release_tree_vector (types
[0]);
3202 release_tree_vector (types
[1]);
3206 /* If TMPL can be successfully instantiated as indicated by
3207 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3209 TMPL is the template. EXPLICIT_TARGS are any explicit template
3210 arguments. ARGLIST is the arguments provided at the call-site.
3211 This does not change ARGLIST. The RETURN_TYPE is the desired type
3212 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3213 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3214 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3216 static struct z_candidate
*
3217 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3218 tree ctype
, tree explicit_targs
, tree first_arg
,
3219 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3220 tree access_path
, tree conversion_path
,
3221 int flags
, tree obj
, unification_kind_t strict
,
3222 tsubst_flags_t complain
)
3224 int ntparms
= DECL_NTPARMS (tmpl
);
3225 tree targs
= make_tree_vec (ntparms
);
3226 unsigned int len
= vec_safe_length (arglist
);
3227 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3228 unsigned int skip_without_in_chrg
= 0;
3229 tree first_arg_without_in_chrg
= first_arg
;
3230 tree
*args_without_in_chrg
;
3231 unsigned int nargs_without_in_chrg
;
3232 unsigned int ia
, ix
;
3234 struct z_candidate
*cand
;
3236 struct rejection_reason
*reason
= NULL
;
3238 conversion
**convs
= NULL
;
3240 /* We don't do deduction on the in-charge parameter, the VTT
3241 parameter or 'this'. */
3242 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3244 if (first_arg_without_in_chrg
!= NULL_TREE
)
3245 first_arg_without_in_chrg
= NULL_TREE
;
3246 else if (return_type
&& strict
== DEDUCE_CALL
)
3247 /* We're deducing for a call to the result of a template conversion
3248 function, so the args don't contain 'this'; leave them alone. */;
3250 ++skip_without_in_chrg
;
3253 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3254 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3255 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3257 if (first_arg_without_in_chrg
!= NULL_TREE
)
3258 first_arg_without_in_chrg
= NULL_TREE
;
3260 ++skip_without_in_chrg
;
3263 if (len
< skip_without_in_chrg
)
3266 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3267 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3268 TREE_TYPE ((*arglist
)[0])))
3270 /* 12.8/6 says, "A declaration of a constructor for a class X is
3271 ill-formed if its first parameter is of type (optionally cv-qualified)
3272 X and either there are no other parameters or else all other
3273 parameters have default arguments. A member function template is never
3274 instantiated to produce such a constructor signature."
3276 So if we're trying to copy an object of the containing class, don't
3277 consider a template constructor that has a first parameter type that
3278 is just a template parameter, as we would deduce a signature that we
3279 would then reject in the code below. */
3280 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3282 firstparm
= TREE_VALUE (firstparm
);
3283 if (PACK_EXPANSION_P (firstparm
))
3284 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3285 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3287 gcc_assert (!explicit_targs
);
3288 reason
= invalid_copy_with_fn_template_rejection ();
3294 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3295 + (len
- skip_without_in_chrg
));
3296 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3298 if (first_arg_without_in_chrg
!= NULL_TREE
)
3300 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3303 for (ix
= skip_without_in_chrg
;
3304 vec_safe_iterate (arglist
, ix
, &arg
);
3307 args_without_in_chrg
[ia
] = arg
;
3310 gcc_assert (ia
== nargs_without_in_chrg
);
3312 errs
= errorcount
+sorrycount
;
3314 convs
= alloc_conversions (nargs
);
3315 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3316 args_without_in_chrg
,
3317 nargs_without_in_chrg
,
3318 return_type
, strict
, flags
, convs
,
3319 false, complain
& tf_decltype
);
3321 if (fn
== error_mark_node
)
3323 /* Don't repeat unification later if it already resulted in errors. */
3324 if (errorcount
+sorrycount
== errs
)
3325 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3326 targs
, args_without_in_chrg
,
3327 nargs_without_in_chrg
,
3328 return_type
, strict
, flags
);
3330 reason
= template_unification_error_rejection ();
3334 /* Now the explicit specifier might have been deduced; check if this
3335 declaration is explicit. If it is and we're ignoring non-converting
3336 constructors, don't add this function to the set of candidates. */
3337 if ((flags
& LOOKUP_ONLYCONVERTING
) && DECL_NONCONVERTING_P (fn
))
3340 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3342 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3343 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3346 /* We're trying to produce a constructor with a prohibited signature,
3347 as discussed above; handle here any cases we didn't catch then,
3349 reason
= invalid_copy_with_fn_template_rejection ();
3354 if (obj
!= NULL_TREE
)
3355 /* Aha, this is a conversion function. */
3356 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3357 access_path
, conversion_path
, complain
);
3359 cand
= add_function_candidate (candidates
, fn
, ctype
,
3360 first_arg
, arglist
, access_path
,
3361 conversion_path
, flags
, convs
, complain
);
3362 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3363 /* This situation can occur if a member template of a template
3364 class is specialized. Then, instantiate_template might return
3365 an instantiation of the specialization, in which case the
3366 DECL_TI_TEMPLATE field will point at the original
3367 specialization. For example:
3369 template <class T> struct S { template <class U> void f(U);
3370 template <> void f(int) {}; };
3374 Here, TMPL will be template <class U> S<double>::f(U).
3375 And, instantiate template will give us the specialization
3376 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3377 for this will point at template <class T> template <> S<T>::f(int),
3378 so that we can find the definition. For the purposes of
3379 overload resolution, however, we want the original TMPL. */
3380 cand
->template_decl
= build_template_info (tmpl
, targs
);
3382 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3383 cand
->explicit_targs
= explicit_targs
;
3387 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3388 access_path
, conversion_path
, 0, reason
, flags
);
3392 static struct z_candidate
*
3393 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3394 tree explicit_targs
, tree first_arg
,
3395 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3396 tree access_path
, tree conversion_path
, int flags
,
3397 unification_kind_t strict
, tsubst_flags_t complain
)
3400 add_template_candidate_real (candidates
, tmpl
, ctype
,
3401 explicit_targs
, first_arg
, arglist
,
3402 return_type
, access_path
, conversion_path
,
3403 flags
, NULL_TREE
, strict
, complain
);
3406 /* Create an overload candidate for the conversion function template TMPL,
3407 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3408 pointer-to-function which will in turn be called with the argument list
3409 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3410 passed on to implicit_conversion. */
3412 static struct z_candidate
*
3413 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3415 const vec
<tree
, va_gc
> *arglist
,
3416 tree return_type
, tree access_path
,
3417 tree conversion_path
, tsubst_flags_t complain
)
3419 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3420 core issue 2189, let's disable this candidate if there are any call
3426 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3427 NULL_TREE
, arglist
, return_type
, access_path
,
3428 conversion_path
, 0, obj
, DEDUCE_CALL
,
3432 /* The CANDS are the set of candidates that were considered for
3433 overload resolution. Return the set of viable candidates, or CANDS
3434 if none are viable. If any of the candidates were viable, set
3435 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3436 considered viable only if it is strictly viable. */
3438 static struct z_candidate
*
3439 splice_viable (struct z_candidate
*cands
,
3443 struct z_candidate
*viable
;
3444 struct z_candidate
**last_viable
;
3445 struct z_candidate
**cand
;
3446 bool found_strictly_viable
= false;
3448 /* Be strict inside templates, since build_over_call won't actually
3449 do the conversions to get pedwarns. */
3450 if (processing_template_decl
)
3454 last_viable
= &viable
;
3455 *any_viable_p
= false;
3460 struct z_candidate
*c
= *cand
;
3462 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3464 /* Be strict in the presence of a viable candidate. Also if
3465 there are template candidates, so that we get deduction errors
3466 for them instead of silently preferring a bad conversion. */
3468 if (viable
&& !found_strictly_viable
)
3470 /* Put any spliced near matches back onto the main list so
3471 that we see them if there is no strict match. */
3472 *any_viable_p
= false;
3473 *last_viable
= cands
;
3476 last_viable
= &viable
;
3480 if (strict_p
? c
->viable
== 1 : c
->viable
)
3485 last_viable
= &c
->next
;
3486 *any_viable_p
= true;
3488 found_strictly_viable
= true;
3494 return viable
? viable
: cands
;
3498 any_strictly_viable (struct z_candidate
*cands
)
3500 for (; cands
; cands
= cands
->next
)
3501 if (cands
->viable
== 1)
3506 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3507 words, it is about to become the "this" pointer for a member
3508 function call. Take the address of the object. */
3511 build_this (tree obj
)
3513 /* In a template, we are only concerned about the type of the
3514 expression, so we can take a shortcut. */
3515 if (processing_template_decl
)
3516 return build_address (obj
);
3518 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3521 /* Returns true iff functions are equivalent. Equivalent functions are
3522 not '==' only if one is a function-local extern function or if
3523 both are extern "C". */
3526 equal_functions (tree fn1
, tree fn2
)
3528 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3530 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3532 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3533 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3534 return decls_match (fn1
, fn2
);
3538 /* Print information about a candidate FN being rejected due to INFO. */
3541 print_conversion_rejection (location_t loc
, struct conversion_info
*info
,
3544 tree from
= info
->from
;
3546 from
= lvalue_type (from
);
3547 if (info
->n_arg
== -1)
3549 /* Conversion of implicit `this' argument failed. */
3550 if (!TYPE_P (info
->from
))
3551 /* A bad conversion for 'this' must be discarding cv-quals. */
3552 inform (loc
, " passing %qT as %<this%> "
3553 "argument discards qualifiers",
3556 inform (loc
, " no known conversion for implicit "
3557 "%<this%> parameter from %qH to %qI",
3558 from
, info
->to_type
);
3560 else if (!TYPE_P (info
->from
))
3562 if (info
->n_arg
>= 0)
3563 inform (loc
, " conversion of argument %d would be ill-formed:",
3565 perform_implicit_conversion (info
->to_type
, info
->from
,
3566 tf_warning_or_error
);
3568 else if (info
->n_arg
== -2)
3569 /* Conversion of conversion function return value failed. */
3570 inform (loc
, " no known conversion from %qH to %qI",
3571 from
, info
->to_type
);
3574 if (TREE_CODE (fn
) == FUNCTION_DECL
)
3575 loc
= get_fndecl_argument_location (fn
, info
->n_arg
);
3576 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3577 info
->n_arg
+ 1, from
, info
->to_type
);
3581 /* Print information about a candidate with WANT parameters and we found
3585 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3587 inform_n (loc
, want
,
3588 " candidate expects %d argument, %d provided",
3589 " candidate expects %d arguments, %d provided",
3593 /* Print information about one overload candidate CANDIDATE. MSGSTR
3594 is the text to print before the candidate itself.
3596 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3597 to have been run through gettext by the caller. This wart makes
3598 life simpler in print_z_candidates and for the translators. */
3601 print_z_candidate (location_t loc
, const char *msgstr
,
3602 struct z_candidate
*candidate
)
3604 const char *msg
= (msgstr
== NULL
3606 : ACONCAT ((msgstr
, " ", NULL
)));
3607 tree fn
= candidate
->fn
;
3608 if (flag_new_inheriting_ctors
)
3609 fn
= strip_inheriting_ctors (fn
);
3610 location_t cloc
= location_of (fn
);
3612 if (identifier_p (fn
))
3615 if (candidate
->num_convs
== 3)
3616 inform (cloc
, "%s%<%D(%T, %T, %T)%> <built-in>", msg
, fn
,
3617 candidate
->convs
[0]->type
,
3618 candidate
->convs
[1]->type
,
3619 candidate
->convs
[2]->type
);
3620 else if (candidate
->num_convs
== 2)
3621 inform (cloc
, "%s%<%D(%T, %T)%> <built-in>", msg
, fn
,
3622 candidate
->convs
[0]->type
,
3623 candidate
->convs
[1]->type
);
3625 inform (cloc
, "%s%<%D(%T)%> <built-in>", msg
, fn
,
3626 candidate
->convs
[0]->type
);
3628 else if (TYPE_P (fn
))
3629 inform (cloc
, "%s%qT <conversion>", msg
, fn
);
3630 else if (candidate
->viable
== -1)
3631 inform (cloc
, "%s%#qD <near match>", msg
, fn
);
3632 else if (DECL_DELETED_FN (fn
))
3633 inform (cloc
, "%s%#qD <deleted>", msg
, fn
);
3635 inform (cloc
, "%s%#qD", msg
, fn
);
3636 if (fn
!= candidate
->fn
)
3638 cloc
= location_of (candidate
->fn
);
3639 inform (cloc
, " inherited here");
3641 /* Give the user some information about why this candidate failed. */
3642 if (candidate
->reason
!= NULL
)
3644 struct rejection_reason
*r
= candidate
->reason
;
3649 print_arity_information (cloc
, r
->u
.arity
.actual
,
3650 r
->u
.arity
.expected
);
3652 case rr_arg_conversion
:
3653 print_conversion_rejection (cloc
, &r
->u
.conversion
, fn
);
3655 case rr_bad_arg_conversion
:
3656 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
, fn
);
3658 case rr_explicit_conversion
:
3659 inform (cloc
, " return type %qT of explicit conversion function "
3660 "cannot be converted to %qT with a qualification "
3661 "conversion", r
->u
.conversion
.from
,
3662 r
->u
.conversion
.to_type
);
3664 case rr_template_conversion
:
3665 inform (cloc
, " conversion from return type %qT of template "
3666 "conversion function specialization to %qT is not an "
3667 "exact match", r
->u
.conversion
.from
,
3668 r
->u
.conversion
.to_type
);
3670 case rr_template_unification
:
3671 /* We use template_unification_error_rejection if unification caused
3672 actual non-SFINAE errors, in which case we don't need to repeat
3674 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3676 inform (cloc
, " substitution of deduced template arguments "
3677 "resulted in errors seen above");
3680 /* Re-run template unification with diagnostics. */
3681 inform (cloc
, " template argument deduction/substitution failed:");
3682 fn_type_unification (r
->u
.template_unification
.tmpl
,
3683 r
->u
.template_unification
.explicit_targs
,
3685 (r
->u
.template_unification
.num_targs
)),
3686 r
->u
.template_unification
.args
,
3687 r
->u
.template_unification
.nargs
,
3688 r
->u
.template_unification
.return_type
,
3689 r
->u
.template_unification
.strict
,
3690 r
->u
.template_unification
.flags
,
3693 case rr_invalid_copy
:
3695 " a constructor taking a single argument of its own "
3696 "class type is invalid");
3698 case rr_constraint_failure
:
3700 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3701 tree args
= r
->u
.template_instantiation
.targs
;
3702 diagnose_constraints (cloc
, tmpl
, args
);
3705 case rr_inherited_ctor
:
3706 inform (cloc
, " an inherited constructor is not a candidate for "
3707 "initialization from an expression of the same or derived "
3712 /* This candidate didn't have any issues or we failed to
3713 handle a particular code. Either way... */
3720 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3722 struct z_candidate
*cand1
;
3723 struct z_candidate
**cand2
;
3728 /* Remove non-viable deleted candidates. */
3730 for (cand2
= &cand1
; *cand2
; )
3732 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3733 && !(*cand2
)->viable
3734 && DECL_DELETED_FN ((*cand2
)->fn
))
3735 *cand2
= (*cand2
)->next
;
3737 cand2
= &(*cand2
)->next
;
3739 /* ...if there are any non-deleted ones. */
3743 /* There may be duplicates in the set of candidates. We put off
3744 checking this condition as long as possible, since we have no way
3745 to eliminate duplicates from a set of functions in less than n^2
3746 time. Now we are about to emit an error message, so it is more
3747 permissible to go slowly. */
3748 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3750 tree fn
= cand1
->fn
;
3751 /* Skip builtin candidates and conversion functions. */
3754 cand2
= &cand1
->next
;
3757 if (DECL_P ((*cand2
)->fn
)
3758 && equal_functions (fn
, (*cand2
)->fn
))
3759 *cand2
= (*cand2
)->next
;
3761 cand2
= &(*cand2
)->next
;
3765 for (; candidates
; candidates
= candidates
->next
)
3766 print_z_candidate (loc
, "candidate:", candidates
);
3769 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3770 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3771 the result of the conversion function to convert it to the final
3772 desired type. Merge the two sequences into a single sequence,
3773 and return the merged sequence. */
3776 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3779 bool bad
= user_seq
->bad_p
;
3781 gcc_assert (user_seq
->kind
== ck_user
);
3783 /* Find the end of the second conversion sequence. */
3784 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3786 /* The entire sequence is a user-conversion sequence. */
3787 (*t
)->user_conv_p
= true;
3792 if ((*t
)->rvaluedness_matches_p
)
3793 /* We're binding a reference directly to the result of the conversion.
3794 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3795 type, but we want it back. */
3796 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3798 /* Replace the identity conversion with the user conversion
3805 /* Handle overload resolution for initializing an object of class type from
3806 an initializer list. First we look for a suitable constructor that
3807 takes a std::initializer_list; if we don't find one, we then look for a
3808 non-list constructor.
3810 Parameters are as for add_candidates, except that the arguments are in
3811 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3812 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3815 add_list_candidates (tree fns
, tree first_arg
,
3816 const vec
<tree
, va_gc
> *args
, tree totype
,
3817 tree explicit_targs
, bool template_only
,
3818 tree conversion_path
, tree access_path
,
3820 struct z_candidate
**candidates
,
3821 tsubst_flags_t complain
)
3823 gcc_assert (*candidates
== NULL
);
3825 /* We're looking for a ctor for list-initialization. */
3826 flags
|= LOOKUP_LIST_INIT_CTOR
;
3827 /* And we don't allow narrowing conversions. We also use this flag to
3828 avoid the copy constructor call for copy-list-initialization. */
3829 flags
|= LOOKUP_NO_NARROWING
;
3831 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3832 tree init_list
= (*args
)[nart
];
3834 /* Always use the default constructor if the list is empty (DR 990). */
3835 if (CONSTRUCTOR_NELTS (init_list
) == 0
3836 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3838 /* If the class has a list ctor, try passing the list as a single
3839 argument first, but only consider list ctors. */
3840 else if (TYPE_HAS_LIST_CTOR (totype
))
3842 flags
|= LOOKUP_LIST_ONLY
;
3843 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3844 explicit_targs
, template_only
, conversion_path
,
3845 access_path
, flags
, candidates
, complain
);
3846 if (any_strictly_viable (*candidates
))
3850 /* Expand the CONSTRUCTOR into a new argument vec. */
3851 vec
<tree
, va_gc
> *new_args
;
3852 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3853 for (unsigned i
= 0; i
< nart
; ++i
)
3854 new_args
->quick_push ((*args
)[i
]);
3855 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3856 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3858 /* We aren't looking for list-ctors anymore. */
3859 flags
&= ~LOOKUP_LIST_ONLY
;
3860 /* We allow more user-defined conversions within an init-list. */
3861 flags
&= ~LOOKUP_NO_CONVERSION
;
3863 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3864 explicit_targs
, template_only
, conversion_path
,
3865 access_path
, flags
, candidates
, complain
);
3868 /* Returns the best overload candidate to perform the requested
3869 conversion. This function is used for three the overloading situations
3870 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3871 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3872 per [dcl.init.ref], so we ignore temporary bindings. */
3874 static struct z_candidate
*
3875 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3876 tsubst_flags_t complain
)
3878 struct z_candidate
*candidates
, *cand
;
3880 tree ctors
= NULL_TREE
;
3881 tree conv_fns
= NULL_TREE
;
3882 conversion
*conv
= NULL
;
3883 tree first_arg
= NULL_TREE
;
3884 vec
<tree
, va_gc
> *args
= NULL
;
3891 fromtype
= TREE_TYPE (expr
);
3893 /* We represent conversion within a hierarchy using RVALUE_CONV and
3894 BASE_CONV, as specified by [over.best.ics]; these become plain
3895 constructor calls, as specified in [dcl.init]. */
3896 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3897 || !DERIVED_FROM_P (totype
, fromtype
));
3899 if (CLASS_TYPE_P (totype
))
3900 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3901 creating a garbage BASELINK; constructors can't be inherited. */
3902 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3904 if (MAYBE_CLASS_TYPE_P (fromtype
))
3906 tree to_nonref
= non_reference (totype
);
3907 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3908 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3909 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3911 /* [class.conv.fct] A conversion function is never used to
3912 convert a (possibly cv-qualified) object to the (possibly
3913 cv-qualified) same object type (or a reference to it), to a
3914 (possibly cv-qualified) base class of that type (or a
3915 reference to it)... */
3918 conv_fns
= lookup_conversions (fromtype
);
3922 flags
|= LOOKUP_NO_CONVERSION
;
3923 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3924 flags
|= LOOKUP_NO_NARROWING
;
3926 /* It's OK to bind a temporary for converting constructor arguments, but
3927 not in converting the return value of a conversion operator. */
3928 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3929 | (flags
& LOOKUP_NO_NARROWING
));
3930 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3934 int ctorflags
= flags
;
3936 first_arg
= build_dummy_object (totype
);
3938 /* We should never try to call the abstract or base constructor
3940 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3941 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3943 args
= make_tree_vector_single (expr
);
3944 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3946 /* List-initialization. */
3947 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3948 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3949 ctorflags
, &candidates
, complain
);
3953 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3954 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3955 ctorflags
, &candidates
, complain
);
3958 for (cand
= candidates
; cand
; cand
= cand
->next
)
3960 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3962 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3963 set, then this is copy-initialization. In that case, "The
3964 result of the call is then used to direct-initialize the
3965 object that is the destination of the copy-initialization."
3968 We represent this in the conversion sequence with an
3969 rvalue conversion, which means a constructor call. */
3970 if (!TYPE_REF_P (totype
)
3971 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3973 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3979 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3980 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3985 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3987 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3988 struct z_candidate
*old_candidates
;
3990 /* If we are called to convert to a reference type, we are trying to
3991 find a direct binding, so don't even consider temporaries. If
3992 we don't find a direct binding, the caller will try again to
3993 look for a temporary binding. */
3994 if (TYPE_REF_P (totype
))
3995 convflags
|= LOOKUP_NO_TEMP_BIND
;
3997 old_candidates
= candidates
;
3998 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
4000 conversion_path
, TYPE_BINFO (fromtype
),
4001 flags
, &candidates
, complain
);
4003 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
4005 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
4007 = implicit_conversion (totype
,
4010 /*c_cast_p=*/false, convflags
,
4013 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
4014 copy-initialization. In that case, "The result of the
4015 call is then used to direct-initialize the object that is
4016 the destination of the copy-initialization." [dcl.init]
4018 We represent this in the conversion sequence with an
4019 rvalue conversion, which means a constructor call. But
4020 don't add a second rvalue conversion if there's already
4021 one there. Which there really shouldn't be, but it's
4022 harmless since we'd add it here anyway. */
4023 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
4024 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
4025 ics
= build_conv (ck_rvalue
, totype
, ics
);
4027 cand
->second_conv
= ics
;
4032 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
4034 EXPR_LOCATION (expr
));
4036 else if (TYPE_REF_P (totype
) && !ics
->rvaluedness_matches_p
4037 && TREE_CODE (TREE_TYPE (totype
)) != FUNCTION_TYPE
)
4039 /* If we are called to convert to a reference type, we are trying
4040 to find a direct binding per [over.match.ref], so rvaluedness
4041 must match for non-functions. */
4044 else if (DECL_NONCONVERTING_P (cand
->fn
)
4045 && ics
->rank
> cr_exact
)
4047 /* 13.3.1.5: For direct-initialization, those explicit
4048 conversion functions that are not hidden within S and
4049 yield type T or a type that can be converted to type T
4050 with a qualification conversion (4.4) are also candidate
4052 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
4053 I've raised this issue with the committee. --jason 9/2011 */
4055 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
4057 else if (cand
->viable
== 1 && ics
->bad_p
)
4061 = bad_arg_conversion_rejection (NULL_TREE
, -2,
4063 EXPR_LOCATION (expr
));
4065 else if (primary_template_specialization_p (cand
->fn
)
4066 && ics
->rank
> cr_exact
)
4068 /* 13.3.3.1.2: If the user-defined conversion is specified by
4069 a specialization of a conversion function template, the
4070 second standard conversion sequence shall have exact match
4073 cand
->reason
= template_conversion_rejection (rettype
, totype
);
4078 candidates
= splice_viable (candidates
, false, &any_viable_p
);
4082 release_tree_vector (args
);
4086 cand
= tourney (candidates
, complain
);
4089 if (complain
& tf_error
)
4091 auto_diagnostic_group d
;
4092 error ("conversion from %qH to %qI is ambiguous",
4094 print_z_candidates (location_of (expr
), candidates
);
4097 cand
= candidates
; /* any one will do */
4098 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
4099 cand
->second_conv
->user_conv_p
= true;
4100 if (!any_strictly_viable (candidates
))
4101 cand
->second_conv
->bad_p
= true;
4102 if (flags
& LOOKUP_ONLYCONVERTING
)
4103 cand
->second_conv
->need_temporary_p
= true;
4104 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
4105 ambiguous conversion is no worse than another user-defined
4112 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
4113 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
4114 else if (cand
->second_conv
->kind
== ck_rvalue
)
4115 /* DR 5: [in the first step of copy-initialization]...if the function
4116 is a constructor, the call initializes a temporary of the
4117 cv-unqualified version of the destination type. */
4118 convtype
= cv_unqualified (totype
);
4121 /* Build the user conversion sequence. */
4125 build_identity_conv (TREE_TYPE (expr
), expr
));
4127 if (cand
->viable
== -1)
4130 /* We're performing the maybe-rvalue overload resolution and
4131 a conversion function is in play. Reject converting the return
4132 value of the conversion function to a base class. */
4133 if ((flags
& LOOKUP_PREFER_RVALUE
) && !DECL_CONSTRUCTOR_P (cand
->fn
))
4134 for (conversion
*t
= cand
->second_conv
; t
; t
= next_conversion (t
))
4135 if (t
->kind
== ck_base
)
4138 /* Remember that this was a list-initialization. */
4139 if (flags
& LOOKUP_NO_NARROWING
)
4140 conv
->check_narrowing
= true;
4142 /* Combine it with the second conversion sequence. */
4143 cand
->second_conv
= merge_conversion_sequences (conv
,
4149 /* Wrapper for above. */
4152 build_user_type_conversion (tree totype
, tree expr
, int flags
,
4153 tsubst_flags_t complain
)
4155 struct z_candidate
*cand
;
4158 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4159 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
4163 if (cand
->second_conv
->kind
== ck_ambig
)
4164 ret
= error_mark_node
;
4167 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4168 ret
= convert_from_reference (expr
);
4174 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4178 /* Subroutine of convert_nontype_argument.
4180 EXPR is an expression used in a context that requires a converted
4181 constant-expression, such as a template non-type parameter. Do any
4182 necessary conversions (that are permitted for converted
4183 constant-expressions) to convert it to the desired type.
4185 If conversion is successful, returns the converted expression;
4186 otherwise, returns error_mark_node. */
4189 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4194 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
4196 if (error_operand_p (expr
))
4197 return error_mark_node
;
4199 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4200 p
= conversion_obstack_alloc (0);
4202 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4204 LOOKUP_IMPLICIT
, complain
);
4206 /* A converted constant expression of type T is an expression, implicitly
4207 converted to type T, where the converted expression is a constant
4208 expression and the implicit conversion sequence contains only
4210 * user-defined conversions,
4211 * lvalue-to-rvalue conversions (7.1),
4212 * array-to-pointer conversions (7.2),
4213 * function-to-pointer conversions (7.3),
4214 * qualification conversions (7.5),
4215 * integral promotions (7.6),
4216 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4217 * null pointer conversions (7.11) from std::nullptr_t,
4218 * null member pointer conversions (7.12) from std::nullptr_t, and
4219 * function pointer conversions (7.13),
4221 and where the reference binding (if any) binds directly. */
4223 for (conversion
*c
= conv
;
4224 conv
&& c
->kind
!= ck_identity
;
4225 c
= next_conversion (c
))
4229 /* A conversion function is OK. If it isn't constexpr, we'll
4230 complain later that the argument isn't constant. */
4232 /* The lvalue-to-rvalue conversion is OK. */
4234 /* Array-to-pointer and function-to-pointer. */
4236 /* Function pointer conversions. */
4238 /* Qualification conversions. */
4243 if (c
->need_temporary_p
)
4245 if (complain
& tf_error
)
4246 error_at (loc
, "initializing %qH with %qI in converted "
4247 "constant expression does not bind directly",
4248 type
, next_conversion (c
)->type
);
4257 t
= next_conversion (c
)->type
;
4258 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4259 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4260 /* Integral promotion or conversion. */
4262 if (NULLPTR_TYPE_P (t
))
4263 /* Conversion from nullptr to pointer or pointer-to-member. */
4266 if (complain
& tf_error
)
4267 error_at (loc
, "conversion from %qH to %qI in a "
4268 "converted constant expression", t
, type
);
4277 /* Avoid confusing convert_nontype_argument by introducing
4278 a redundant conversion to the same reference type. */
4279 if (conv
&& conv
->kind
== ck_ref_bind
4280 && REFERENCE_REF_P (expr
))
4282 tree ref
= TREE_OPERAND (expr
, 0);
4283 if (same_type_p (type
, TREE_TYPE (ref
)))
4289 conv
->check_narrowing
= true;
4290 conv
->check_narrowing_const_only
= true;
4291 expr
= convert_like (conv
, expr
, complain
);
4295 if (complain
& tf_error
)
4296 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4297 TREE_TYPE (expr
), type
);
4298 expr
= error_mark_node
;
4301 /* Free all the conversions we allocated. */
4302 obstack_free (&conversion_obstack
, p
);
4307 /* Do any initial processing on the arguments to a function call. */
4309 static vec
<tree
, va_gc
> *
4310 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4315 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4317 if (error_operand_p (arg
))
4319 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4321 if (complain
& tf_error
)
4322 error ("invalid use of void expression");
4325 else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg
), arg
, complain
))
4331 /* Perform overload resolution on FN, which is called with the ARGS.
4333 Return the candidate function selected by overload resolution, or
4334 NULL if the event that overload resolution failed. In the case
4335 that overload resolution fails, *CANDIDATES will be the set of
4336 candidates considered, and ANY_VIABLE_P will be set to true or
4337 false to indicate whether or not any of the candidates were
4340 The ARGS should already have gone through RESOLVE_ARGS before this
4341 function is called. */
4343 static struct z_candidate
*
4344 perform_overload_resolution (tree fn
,
4345 const vec
<tree
, va_gc
> *args
,
4346 struct z_candidate
**candidates
,
4347 bool *any_viable_p
, tsubst_flags_t complain
)
4349 struct z_candidate
*cand
;
4350 tree explicit_targs
;
4353 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4355 explicit_targs
= NULL_TREE
;
4359 *any_viable_p
= true;
4362 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4363 || TREE_CODE (fn
) == TEMPLATE_DECL
4364 || TREE_CODE (fn
) == OVERLOAD
4365 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4367 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4369 explicit_targs
= TREE_OPERAND (fn
, 1);
4370 fn
= TREE_OPERAND (fn
, 0);
4374 /* Add the various candidate functions. */
4375 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4376 explicit_targs
, template_only
,
4377 /*conversion_path=*/NULL_TREE
,
4378 /*access_path=*/NULL_TREE
,
4380 candidates
, complain
);
4382 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4384 cand
= tourney (*candidates
, complain
);
4388 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4392 /* Print an error message about being unable to build a call to FN with
4393 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4394 be located; CANDIDATES is a possibly empty list of such
4398 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4399 struct z_candidate
*candidates
)
4401 tree targs
= NULL_TREE
;
4402 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4404 targs
= TREE_OPERAND (fn
, 1);
4405 fn
= TREE_OPERAND (fn
, 0);
4407 tree name
= OVL_NAME (fn
);
4408 location_t loc
= location_of (name
);
4410 name
= lookup_template_function (name
, targs
);
4412 auto_diagnostic_group d
;
4413 if (!any_strictly_viable (candidates
))
4414 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4415 name
, build_tree_list_vec (args
));
4417 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4418 name
, build_tree_list_vec (args
));
4420 print_z_candidates (loc
, candidates
);
4423 /* Return an expression for a call to FN (a namespace-scope function,
4424 or a static member function) with the ARGS. This may change
4428 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4429 tsubst_flags_t complain
)
4431 struct z_candidate
*candidates
, *cand
;
4436 if (args
!= NULL
&& *args
!= NULL
)
4438 *args
= resolve_args (*args
, complain
);
4440 return error_mark_node
;
4444 tm_malloc_replacement (fn
);
4446 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4447 p
= conversion_obstack_alloc (0);
4449 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4454 if (complain
& tf_error
)
4456 // If there is a single (non-viable) function candidate,
4457 // let the error be diagnosed by cp_build_function_call_vec.
4458 if (!any_viable_p
&& candidates
&& ! candidates
->next
4459 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4460 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4462 // Otherwise, emit notes for non-viable candidates.
4463 print_error_for_call_failure (fn
, *args
, candidates
);
4465 result
= error_mark_node
;
4469 int flags
= LOOKUP_NORMAL
;
4470 /* If fn is template_id_expr, the call has explicit template arguments
4471 (e.g. func<int>(5)), communicate this info to build_over_call
4472 through flags so that later we can use it to decide whether to warn
4473 about peculiar null pointer conversion. */
4474 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4476 /* If overload resolution selects a specialization of a
4477 function concept for non-dependent template arguments,
4478 the expression is true if the constraints are satisfied
4479 and false otherwise.
4481 NOTE: This is an extension of Concepts Lite TS that
4482 allows constraints to be used in expressions. */
4483 if (flag_concepts
&& !processing_template_decl
)
4485 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4486 tree targs
= DECL_TI_ARGS (cand
->fn
);
4487 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4488 if (DECL_DECLARED_CONCEPT_P (decl
))
4489 return evaluate_function_concept (decl
, targs
);
4492 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4495 result
= build_over_call (cand
, flags
, complain
);
4498 /* Free all the conversions we allocated. */
4499 obstack_free (&conversion_obstack
, p
);
4504 /* Build a call to a global operator new. FNNAME is the name of the
4505 operator (either "operator new" or "operator new[]") and ARGS are
4506 the arguments provided. This may change ARGS. *SIZE points to the
4507 total number of bytes required by the allocation, and is updated if
4508 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4509 be used. If this function determines that no cookie should be
4510 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4511 is not NULL_TREE, it is evaluated before calculating the final
4512 array size, and if it fails, the array size is replaced with
4513 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4514 is non-NULL, it will be set, upon return, to the allocation
4518 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4519 tree
*size
, tree
*cookie_size
,
4520 tree align_arg
, tree size_check
,
4521 tree
*fn
, tsubst_flags_t complain
)
4523 tree original_size
= *size
;
4525 struct z_candidate
*candidates
;
4526 struct z_candidate
*cand
= NULL
;
4531 /* Set to (size_t)-1 if the size check fails. */
4532 if (size_check
!= NULL_TREE
)
4534 tree errval
= TYPE_MAX_VALUE (sizetype
);
4535 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4536 errval
= throw_bad_array_new_length ();
4537 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4538 original_size
, errval
);
4540 vec_safe_insert (*args
, 0, *size
);
4541 *args
= resolve_args (*args
, complain
);
4543 return error_mark_node
;
4549 If this lookup fails to find the name, or if the allocated type
4550 is not a class type, the allocation function's name is looked
4551 up in the global scope.
4553 we disregard block-scope declarations of "operator new". */
4554 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4555 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4559 vec
<tree
, va_gc
>* align_args
4560 = vec_copy_and_insert (*args
, align_arg
, 1);
4561 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4562 &any_viable_p
, tf_none
);
4565 /* If no aligned allocation function matches, try again without the
4569 /* Figure out what function is being called. */
4571 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4574 /* If no suitable function could be found, issue an error message
4578 if (complain
& tf_error
)
4579 print_error_for_call_failure (fns
, *args
, candidates
);
4580 return error_mark_node
;
4583 /* If a cookie is required, add some extra space. Whether
4584 or not a cookie is required cannot be determined until
4585 after we know which function was called. */
4588 bool use_cookie
= true;
4591 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4592 /* Skip the size_t parameter. */
4593 arg_types
= TREE_CHAIN (arg_types
);
4594 /* Check the remaining parameters (if any). */
4596 && TREE_CHAIN (arg_types
) == void_list_node
4597 && same_type_p (TREE_VALUE (arg_types
),
4600 /* If we need a cookie, adjust the number of bytes allocated. */
4603 /* Update the total size. */
4604 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4607 /* Set to (size_t)-1 if the size check fails. */
4608 gcc_assert (size_check
!= NULL_TREE
);
4609 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4610 *size
, TYPE_MAX_VALUE (sizetype
));
4612 /* Update the argument list to reflect the adjusted size. */
4613 (**args
)[0] = *size
;
4616 *cookie_size
= NULL_TREE
;
4619 /* Tell our caller which function we decided to call. */
4623 /* Build the CALL_EXPR. */
4624 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4627 /* Build a new call to operator(). This may change ARGS. */
4630 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4632 struct z_candidate
*candidates
= 0, *cand
;
4633 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4635 tree result
= NULL_TREE
;
4638 obj
= mark_lvalue_use (obj
);
4640 if (error_operand_p (obj
))
4641 return error_mark_node
;
4643 tree type
= TREE_TYPE (obj
);
4645 obj
= prep_operand (obj
);
4647 if (TYPE_PTRMEMFUNC_P (type
))
4649 if (complain
& tf_error
)
4650 /* It's no good looking for an overloaded operator() on a
4651 pointer-to-member-function. */
4652 error ("pointer-to-member function %qE cannot be called without "
4653 "an object; consider using %<.*%> or %<->*%>", obj
);
4654 return error_mark_node
;
4657 if (TYPE_BINFO (type
))
4659 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4660 if (fns
== error_mark_node
)
4661 return error_mark_node
;
4666 if (args
!= NULL
&& *args
!= NULL
)
4668 *args
= resolve_args (*args
, complain
);
4670 return error_mark_node
;
4673 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4674 p
= conversion_obstack_alloc (0);
4678 first_mem_arg
= obj
;
4680 add_candidates (BASELINK_FUNCTIONS (fns
),
4681 first_mem_arg
, *args
, NULL_TREE
,
4683 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4684 LOOKUP_NORMAL
, &candidates
, complain
);
4687 convs
= lookup_conversions (type
);
4689 for (; convs
; convs
= TREE_CHAIN (convs
))
4691 tree totype
= TREE_TYPE (convs
);
4693 if (TYPE_PTRFN_P (totype
)
4694 || TYPE_REFFN_P (totype
)
4695 || (TYPE_REF_P (totype
)
4696 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4697 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4701 if (DECL_NONCONVERTING_P (fn
))
4704 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4705 add_template_conv_candidate
4706 (&candidates
, fn
, obj
, *args
, totype
,
4707 /*access_path=*/NULL_TREE
,
4708 /*conversion_path=*/NULL_TREE
, complain
);
4710 add_conv_candidate (&candidates
, fn
, obj
,
4711 *args
, /*conversion_path=*/NULL_TREE
,
4712 /*access_path=*/NULL_TREE
, complain
);
4716 /* Be strict here because if we choose a bad conversion candidate, the
4717 errors we get won't mention the call context. */
4718 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4721 if (complain
& tf_error
)
4723 auto_diagnostic_group d
;
4724 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4725 build_tree_list_vec (*args
));
4726 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4728 result
= error_mark_node
;
4732 cand
= tourney (candidates
, complain
);
4735 if (complain
& tf_error
)
4737 auto_diagnostic_group d
;
4738 error ("call of %<(%T) (%A)%> is ambiguous",
4739 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4740 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4742 result
= error_mark_node
;
4744 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4745 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4746 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4747 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4750 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4751 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4755 gcc_checking_assert (TYPE_P (cand
->fn
));
4756 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4758 obj
= convert_from_reference (obj
);
4759 result
= cp_build_function_call_vec (obj
, args
, complain
);
4763 /* Free all the conversions we allocated. */
4764 obstack_free (&conversion_obstack
, p
);
4769 /* Wrapper for above. */
4772 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4775 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4776 ret
= build_op_call_1 (obj
, args
, complain
);
4777 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4781 /* Called by op_error to prepare format strings suitable for the error
4782 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4783 and a suffix (controlled by NTYPES). */
4786 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4790 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4791 : G_("no match for "), errmsg
, NULL
);
4794 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4795 else if (ntypes
== 2)
4796 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4798 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4804 op_error (const op_location_t
&loc
,
4805 enum tree_code code
, enum tree_code code2
,
4806 tree arg1
, tree arg2
, tree arg3
, bool match
)
4808 bool assop
= code
== MODIFY_EXPR
;
4809 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4814 if (flag_diagnostics_show_caret
)
4815 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4817 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4819 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4820 "in %<%E ? %E : %E%>"), 3, match
),
4822 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4825 case POSTINCREMENT_EXPR
:
4826 case POSTDECREMENT_EXPR
:
4827 if (flag_diagnostics_show_caret
)
4828 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4829 opname
, TREE_TYPE (arg1
));
4831 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4833 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4837 if (flag_diagnostics_show_caret
)
4838 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4839 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4841 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4843 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4848 if (flag_diagnostics_show_caret
)
4849 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4850 opname
, TREE_TYPE (arg1
));
4852 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4853 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4858 if (flag_diagnostics_show_caret
)
4860 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4862 op_error_string (G_("%<operator%s%>"), 2, match
),
4863 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4866 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4868 opname
, arg1
, opname
, arg2
,
4869 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4871 if (flag_diagnostics_show_caret
)
4872 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4873 opname
, TREE_TYPE (arg1
));
4875 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4877 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4882 /* Return the implicit conversion sequence that could be used to
4883 convert E1 to E2 in [expr.cond]. */
4886 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4888 tree t1
= non_reference (TREE_TYPE (e1
));
4889 tree t2
= non_reference (TREE_TYPE (e2
));
4895 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4896 implicitly converted (clause _conv_) to the type "lvalue reference to
4897 T2", subject to the constraint that in the conversion the
4898 reference must bind directly (_dcl.init.ref_) to an lvalue.
4900 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4901 implicitly converted to the type "rvalue reference to T2", subject to
4902 the constraint that the reference must bind directly. */
4905 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4906 conv
= implicit_conversion (rtype
,
4910 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4911 |LOOKUP_ONLYCONVERTING
,
4913 if (conv
&& !conv
->bad_p
)
4917 /* If E2 is a prvalue or if neither of the conversions above can be done
4918 and at least one of the operands has (possibly cv-qualified) class
4920 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4925 If E1 and E2 have class type, and the underlying class types are
4926 the same or one is a base class of the other: E1 can be converted
4927 to match E2 if the class of T2 is the same type as, or a base
4928 class of, the class of T1, and the cv-qualification of T2 is the
4929 same cv-qualification as, or a greater cv-qualification than, the
4930 cv-qualification of T1. If the conversion is applied, E1 is
4931 changed to an rvalue of type T2 that still refers to the original
4932 source class object (or the appropriate subobject thereof). */
4933 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4934 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4936 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4938 conv
= build_identity_conv (t1
, e1
);
4939 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4940 TYPE_MAIN_VARIANT (t2
)))
4941 conv
= build_conv (ck_base
, t2
, conv
);
4943 conv
= build_conv (ck_rvalue
, t2
, conv
);
4952 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4953 converted to the type that expression E2 would have if E2 were
4954 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4955 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4956 LOOKUP_IMPLICIT
, complain
);
4959 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4960 arguments to the conditional expression. */
4963 build_conditional_expr_1 (const op_location_t
&loc
,
4964 tree arg1
, tree arg2
, tree arg3
,
4965 tsubst_flags_t complain
)
4969 tree result
= NULL_TREE
;
4970 tree result_type
= NULL_TREE
;
4971 bool is_glvalue
= true;
4972 struct z_candidate
*candidates
= 0;
4973 struct z_candidate
*cand
;
4975 tree orig_arg2
, orig_arg3
;
4977 /* As a G++ extension, the second argument to the conditional can be
4978 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4979 c'.) If the second operand is omitted, make sure it is
4980 calculated only once. */
4983 if (complain
& tf_error
)
4984 pedwarn (loc
, OPT_Wpedantic
,
4985 "ISO C++ forbids omitting the middle term of a ?: expression");
4987 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
4988 warn_for_omitted_condop (loc
, arg1
);
4990 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4991 if (lvalue_p (arg1
))
4992 arg2
= arg1
= cp_stabilize_reference (arg1
);
4994 arg2
= arg1
= cp_save_expr (arg1
);
4997 /* If something has already gone wrong, just pass that fact up the
4999 if (error_operand_p (arg1
)
5000 || error_operand_p (arg2
)
5001 || error_operand_p (arg3
))
5002 return error_mark_node
;
5007 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
5009 tree arg1_type
= TREE_TYPE (arg1
);
5011 /* If arg1 is another cond_expr choosing between -1 and 0,
5012 then we can use its comparison. It may help to avoid
5013 additional comparison, produce more accurate diagnostics
5014 and enables folding. */
5015 if (TREE_CODE (arg1
) == VEC_COND_EXPR
5016 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
5017 && integer_zerop (TREE_OPERAND (arg1
, 2)))
5018 arg1
= TREE_OPERAND (arg1
, 0);
5020 arg1
= force_rvalue (arg1
, complain
);
5021 arg2
= force_rvalue (arg2
, complain
);
5022 arg3
= force_rvalue (arg3
, complain
);
5024 /* force_rvalue can return error_mark on valid arguments. */
5025 if (error_operand_p (arg1
)
5026 || error_operand_p (arg2
)
5027 || error_operand_p (arg3
))
5028 return error_mark_node
;
5030 arg2_type
= TREE_TYPE (arg2
);
5031 arg3_type
= TREE_TYPE (arg3
);
5033 if (!VECTOR_TYPE_P (arg2_type
)
5034 && !VECTOR_TYPE_P (arg3_type
))
5036 /* Rely on the error messages of the scalar version. */
5037 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
5038 orig_arg2
, orig_arg3
, complain
);
5039 if (scal
== error_mark_node
)
5040 return error_mark_node
;
5041 tree stype
= TREE_TYPE (scal
);
5042 tree ctype
= TREE_TYPE (arg1_type
);
5043 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
5044 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
5046 if (complain
& tf_error
)
5047 error_at (loc
, "inferred scalar type %qT is not an integer or "
5048 "floating point type of the same size as %qT", stype
,
5049 COMPARISON_CLASS_P (arg1
)
5050 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
5052 return error_mark_node
;
5055 tree vtype
= build_opaque_vector_type (stype
,
5056 TYPE_VECTOR_SUBPARTS (arg1_type
));
5057 /* We could pass complain & tf_warning to unsafe_conversion_p,
5058 but the warnings (like Wsign-conversion) have already been
5059 given by the scalar build_conditional_expr_1. We still check
5060 unsafe_conversion_p to forbid truncating long long -> float. */
5061 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
5063 if (complain
& tf_error
)
5064 error_at (loc
, "conversion of scalar %qH to vector %qI "
5065 "involves truncation", arg2_type
, vtype
);
5066 return error_mark_node
;
5068 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
5070 if (complain
& tf_error
)
5071 error_at (loc
, "conversion of scalar %qH to vector %qI "
5072 "involves truncation", arg3_type
, vtype
);
5073 return error_mark_node
;
5076 arg2
= cp_convert (stype
, arg2
, complain
);
5077 arg2
= save_expr (arg2
);
5078 arg2
= build_vector_from_val (vtype
, arg2
);
5080 arg3
= cp_convert (stype
, arg3
, complain
);
5081 arg3
= save_expr (arg3
);
5082 arg3
= build_vector_from_val (vtype
, arg3
);
5086 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5088 enum stv_conv convert_flag
=
5089 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5090 complain
& tf_error
);
5092 switch (convert_flag
)
5095 return error_mark_node
;
5098 arg2
= save_expr (arg2
);
5099 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5100 arg2
= build_vector_from_val (arg3_type
, arg2
);
5101 arg2_type
= TREE_TYPE (arg2
);
5106 arg3
= save_expr (arg3
);
5107 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5108 arg3
= build_vector_from_val (arg2_type
, arg3
);
5109 arg3_type
= TREE_TYPE (arg3
);
5117 if (!same_type_p (arg2_type
, arg3_type
)
5118 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5119 TYPE_VECTOR_SUBPARTS (arg2_type
))
5120 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5122 if (complain
& tf_error
)
5124 "incompatible vector types in conditional expression: "
5125 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5126 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5127 return error_mark_node
;
5130 if (!COMPARISON_CLASS_P (arg1
))
5132 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5133 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5135 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5140 The first expression is implicitly converted to bool (clause
5142 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5144 if (error_operand_p (arg1
))
5145 return error_mark_node
;
5149 If either the second or the third operand has type (possibly
5150 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5151 array-to-pointer (_conv.array_), and function-to-pointer
5152 (_conv.func_) standard conversions are performed on the second
5153 and third operands. */
5154 arg2_type
= unlowered_expr_type (arg2
);
5155 arg3_type
= unlowered_expr_type (arg3
);
5156 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5158 /* 'void' won't help in resolving an overloaded expression on the
5159 other side, so require it to resolve by itself. */
5160 if (arg2_type
== unknown_type_node
)
5162 arg2
= resolve_nondeduced_context_or_error (arg2
, complain
);
5163 arg2_type
= TREE_TYPE (arg2
);
5165 if (arg3_type
== unknown_type_node
)
5167 arg3
= resolve_nondeduced_context_or_error (arg3
, complain
);
5168 arg3_type
= TREE_TYPE (arg3
);
5173 One of the following shall hold:
5175 --The second or the third operand (but not both) is a
5176 throw-expression (_except.throw_); the result is of the type
5177 and value category of the other.
5179 --Both the second and the third operands have type void; the
5180 result is of type void and is a prvalue. */
5181 if (TREE_CODE (arg2
) == THROW_EXPR
5182 && TREE_CODE (arg3
) != THROW_EXPR
)
5184 result_type
= arg3_type
;
5185 is_glvalue
= glvalue_p (arg3
);
5187 else if (TREE_CODE (arg2
) != THROW_EXPR
5188 && TREE_CODE (arg3
) == THROW_EXPR
)
5190 result_type
= arg2_type
;
5191 is_glvalue
= glvalue_p (arg2
);
5193 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5195 result_type
= void_type_node
;
5200 if (complain
& tf_error
)
5202 if (VOID_TYPE_P (arg2_type
))
5203 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5204 "second operand to the conditional operator "
5205 "is of type %<void%>, but the third operand is "
5206 "neither a throw-expression nor of type %<void%>");
5208 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5209 "third operand to the conditional operator "
5210 "is of type %<void%>, but the second operand is "
5211 "neither a throw-expression nor of type %<void%>");
5213 return error_mark_node
;
5216 goto valid_operands
;
5220 Otherwise, if the second and third operand have different types,
5221 and either has (possibly cv-qualified) class type, or if both are
5222 glvalues of the same value category and the same type except for
5223 cv-qualification, an attempt is made to convert each of those operands
5224 to the type of the other. */
5225 else if (!same_type_p (arg2_type
, arg3_type
)
5226 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5227 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5229 && glvalue_p (arg2
) && glvalue_p (arg3
)
5230 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5234 bool converted
= false;
5236 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5237 p
= conversion_obstack_alloc (0);
5239 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5240 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5244 If both can be converted, or one can be converted but the
5245 conversion is ambiguous, the program is ill-formed. If
5246 neither can be converted, the operands are left unchanged and
5247 further checking is performed as described below. If exactly
5248 one conversion is possible, that conversion is applied to the
5249 chosen operand and the converted operand is used in place of
5250 the original operand for the remainder of this section. */
5251 if ((conv2
&& !conv2
->bad_p
5252 && conv3
&& !conv3
->bad_p
)
5253 || (conv2
&& conv2
->kind
== ck_ambig
)
5254 || (conv3
&& conv3
->kind
== ck_ambig
))
5256 if (complain
& tf_error
)
5258 error_at (loc
, "operands to ?: have different types %qT and %qT",
5259 arg2_type
, arg3_type
);
5260 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5261 inform (loc
, " and each type can be converted to the other");
5262 else if (conv2
&& conv2
->kind
== ck_ambig
)
5263 convert_like (conv2
, arg2
, complain
);
5265 convert_like (conv3
, arg3
, complain
);
5267 result
= error_mark_node
;
5269 else if (conv2
&& !conv2
->bad_p
)
5271 arg2
= convert_like (conv2
, arg2
, complain
);
5272 arg2
= convert_from_reference (arg2
);
5273 arg2_type
= TREE_TYPE (arg2
);
5274 /* Even if CONV2 is a valid conversion, the result of the
5275 conversion may be invalid. For example, if ARG3 has type
5276 "volatile X", and X does not have a copy constructor
5277 accepting a "volatile X&", then even if ARG2 can be
5278 converted to X, the conversion will fail. */
5279 if (error_operand_p (arg2
))
5280 result
= error_mark_node
;
5283 else if (conv3
&& !conv3
->bad_p
)
5285 arg3
= convert_like (conv3
, arg3
, complain
);
5286 arg3
= convert_from_reference (arg3
);
5287 arg3_type
= TREE_TYPE (arg3
);
5288 if (error_operand_p (arg3
))
5289 result
= error_mark_node
;
5293 /* Free all the conversions we allocated. */
5294 obstack_free (&conversion_obstack
, p
);
5299 /* If, after the conversion, both operands have class type,
5300 treat the cv-qualification of both operands as if it were the
5301 union of the cv-qualification of the operands.
5303 The standard is not clear about what to do in this
5304 circumstance. For example, if the first operand has type
5305 "const X" and the second operand has a user-defined
5306 conversion to "volatile X", what is the type of the second
5307 operand after this step? Making it be "const X" (matching
5308 the first operand) seems wrong, as that discards the
5309 qualification without actually performing a copy. Leaving it
5310 as "volatile X" seems wrong as that will result in the
5311 conditional expression failing altogether, even though,
5312 according to this step, the one operand could be converted to
5313 the type of the other. */
5315 && CLASS_TYPE_P (arg2_type
)
5316 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5317 arg2_type
= arg3_type
=
5318 cp_build_qualified_type (arg2_type
,
5319 cp_type_quals (arg2_type
)
5320 | cp_type_quals (arg3_type
));
5325 If the second and third operands are glvalues of the same value
5326 category and have the same type, the result is of that type and
5328 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5329 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5330 && same_type_p (arg2_type
, arg3_type
))
5332 result_type
= arg2_type
;
5333 arg2
= mark_lvalue_use (arg2
);
5334 arg3
= mark_lvalue_use (arg3
);
5335 goto valid_operands
;
5340 Otherwise, the result is an rvalue. If the second and third
5341 operand do not have the same type, and either has (possibly
5342 cv-qualified) class type, overload resolution is used to
5343 determine the conversions (if any) to be applied to the operands
5344 (_over.match.oper_, _over.built_). */
5346 if (!same_type_p (arg2_type
, arg3_type
)
5347 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5353 /* Rearrange the arguments so that add_builtin_candidate only has
5354 to know about two args. In build_builtin_candidate, the
5355 arguments are unscrambled. */
5359 add_builtin_candidates (&candidates
,
5362 ovl_op_identifier (false, COND_EXPR
),
5364 LOOKUP_NORMAL
, complain
);
5368 If the overload resolution fails, the program is
5370 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5373 if (complain
& tf_error
)
5374 error_at (loc
, "operands to ?: have different types %qT and %qT",
5375 arg2_type
, arg3_type
);
5376 return error_mark_node
;
5378 cand
= tourney (candidates
, complain
);
5381 if (complain
& tf_error
)
5383 auto_diagnostic_group d
;
5384 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5385 print_z_candidates (loc
, candidates
);
5387 return error_mark_node
;
5392 Otherwise, the conversions thus determined are applied, and
5393 the converted operands are used in place of the original
5394 operands for the remainder of this section. */
5395 conv
= cand
->convs
[0];
5396 arg1
= convert_like (conv
, arg1
, complain
);
5397 conv
= cand
->convs
[1];
5398 arg2
= convert_like (conv
, arg2
, complain
);
5399 arg2_type
= TREE_TYPE (arg2
);
5400 conv
= cand
->convs
[2];
5401 arg3
= convert_like (conv
, arg3
, complain
);
5402 arg3_type
= TREE_TYPE (arg3
);
5407 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5408 and function-to-pointer (_conv.func_) standard conversions are
5409 performed on the second and third operands.
5411 We need to force the lvalue-to-rvalue conversion here for class types,
5412 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5413 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5416 arg2
= force_rvalue (arg2
, complain
);
5417 if (!CLASS_TYPE_P (arg2_type
))
5418 arg2_type
= TREE_TYPE (arg2
);
5420 arg3
= force_rvalue (arg3
, complain
);
5421 if (!CLASS_TYPE_P (arg3_type
))
5422 arg3_type
= TREE_TYPE (arg3
);
5424 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5425 return error_mark_node
;
5429 After those conversions, one of the following shall hold:
5431 --The second and third operands have the same type; the result is of
5433 if (same_type_p (arg2_type
, arg3_type
))
5434 result_type
= arg2_type
;
5437 --The second and third operands have arithmetic or enumeration
5438 type; the usual arithmetic conversions are performed to bring
5439 them to a common type, and the result is of that type. */
5440 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5441 || UNSCOPED_ENUM_P (arg2_type
))
5442 && (ARITHMETIC_TYPE_P (arg3_type
)
5443 || UNSCOPED_ENUM_P (arg3_type
)))
5445 /* In this case, there is always a common type. */
5446 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5448 if (complain
& tf_warning
)
5449 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5450 "implicit conversion from %qH to %qI to "
5451 "match other result of conditional",
5454 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5455 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5457 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5458 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5459 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5460 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5461 && (DECL_CONTEXT (stripped_orig_arg2
)
5462 == DECL_CONTEXT (stripped_orig_arg3
)))
5463 /* Two enumerators from the same enumeration can have different
5464 types when the enumeration is still being defined. */;
5465 else if (complain
& tf_warning
)
5466 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5467 "conditional expression: %qT vs %qT",
5468 arg2_type
, arg3_type
);
5470 else if (extra_warnings
5471 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5472 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5473 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5474 && !same_type_p (arg2_type
,
5475 type_promotes_to (arg3_type
)))))
5477 if (complain
& tf_warning
)
5478 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5479 "conditional expression");
5482 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5483 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5487 --The second and third operands have pointer type, or one has
5488 pointer type and the other is a null pointer constant; pointer
5489 conversions (_conv.ptr_) and qualification conversions
5490 (_conv.qual_) are performed to bring them to their composite
5491 pointer type (_expr.rel_). The result is of the composite
5494 --The second and third operands have pointer to member type, or
5495 one has pointer to member type and the other is a null pointer
5496 constant; pointer to member conversions (_conv.mem_) and
5497 qualification conversions (_conv.qual_) are performed to bring
5498 them to a common type, whose cv-qualification shall match the
5499 cv-qualification of either the second or the third operand.
5500 The result is of the common type. */
5501 else if ((null_ptr_cst_p (arg2
)
5502 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5503 || (null_ptr_cst_p (arg3
)
5504 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5505 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5506 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5507 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5509 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5510 arg3
, CPO_CONDITIONAL_EXPR
,
5512 if (result_type
== error_mark_node
)
5513 return error_mark_node
;
5514 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5515 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5520 if (complain
& tf_error
)
5521 error_at (loc
, "operands to ?: have different types %qT and %qT",
5522 arg2_type
, arg3_type
);
5523 return error_mark_node
;
5526 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5527 return error_mark_node
;
5530 if (processing_template_decl
&& is_glvalue
)
5532 /* Let lvalue_kind know this was a glvalue. */
5533 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5534 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5537 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5539 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5540 warn here, because the COND_EXPR will be turned into ARG2. */
5541 if (warn_duplicated_branches
5542 && (complain
& tf_warning
)
5543 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5544 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5545 "this condition has identical branches");
5547 /* We can't use result_type below, as fold might have returned a
5552 /* Expand both sides into the same slot, hopefully the target of
5553 the ?: expression. We used to check for TARGET_EXPRs here,
5554 but now we sometimes wrap them in NOP_EXPRs so the test would
5556 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5557 result
= get_target_expr_sfinae (result
, complain
);
5558 /* If this expression is an rvalue, but might be mistaken for an
5559 lvalue, we must add a NON_LVALUE_EXPR. */
5560 result
= rvalue (result
);
5563 result
= force_paren_expr (result
);
5568 /* Wrapper for above. */
5571 build_conditional_expr (const op_location_t
&loc
,
5572 tree arg1
, tree arg2
, tree arg3
,
5573 tsubst_flags_t complain
)
5576 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5577 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5578 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5582 /* OPERAND is an operand to an expression. Perform necessary steps
5583 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5587 prep_operand (tree operand
)
5591 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5592 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5593 /* Make sure the template type is instantiated now. */
5594 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5600 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5601 OVERLOAD) to the CANDIDATES, returning an updated list of
5602 CANDIDATES. The ARGS are the arguments provided to the call;
5603 if FIRST_ARG is non-null it is the implicit object argument,
5604 otherwise the first element of ARGS is used if needed. The
5605 EXPLICIT_TARGS are explicit template arguments provided.
5606 TEMPLATE_ONLY is true if only template functions should be
5607 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5608 add_function_candidate. */
5611 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5613 tree explicit_targs
, bool template_only
,
5614 tree conversion_path
, tree access_path
,
5616 struct z_candidate
**candidates
,
5617 tsubst_flags_t complain
)
5620 const vec
<tree
, va_gc
> *non_static_args
;
5621 bool check_list_ctor
= false;
5622 bool check_converting
= false;
5623 unification_kind_t strict
;
5628 /* Precalculate special handling of constructors and conversion ops. */
5629 tree fn
= OVL_FIRST (fns
);
5630 if (DECL_CONV_FN_P (fn
))
5632 check_list_ctor
= false;
5633 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5634 if (flags
& LOOKUP_NO_CONVERSION
)
5635 /* We're doing return_type(x). */
5636 strict
= DEDUCE_CONV
;
5638 /* We're doing x.operator return_type(). */
5639 strict
= DEDUCE_EXACT
;
5640 /* [over.match.funcs] For conversion functions, the function
5641 is considered to be a member of the class of the implicit
5642 object argument for the purpose of defining the type of
5643 the implicit object parameter. */
5644 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5648 if (DECL_CONSTRUCTOR_P (fn
))
5650 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5651 /* For list-initialization we consider explicit constructors
5652 and complain if one is chosen. */
5654 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5655 == LOOKUP_ONLYCONVERTING
);
5657 strict
= DEDUCE_CALL
;
5658 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5662 non_static_args
= args
;
5664 /* Delay creating the implicit this parameter until it is needed. */
5665 non_static_args
= NULL
;
5667 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5671 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5673 if (check_list_ctor
&& !is_list_ctor (fn
))
5676 tree fn_first_arg
= NULL_TREE
;
5677 const vec
<tree
, va_gc
> *fn_args
= args
;
5679 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5681 /* Figure out where the object arg comes from. If this
5682 function is a non-static member and we didn't get an
5683 implicit object argument, move it out of args. */
5684 if (first_arg
== NULL_TREE
)
5688 vec
<tree
, va_gc
> *tempvec
;
5689 vec_alloc (tempvec
, args
->length () - 1);
5690 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5691 tempvec
->quick_push (arg
);
5692 non_static_args
= tempvec
;
5693 first_arg
= (*args
)[0];
5696 fn_first_arg
= first_arg
;
5697 fn_args
= non_static_args
;
5700 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5701 add_template_candidate (candidates
,
5713 else if (!template_only
)
5714 add_function_candidate (candidates
,
5727 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5728 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5731 op_is_ordered (tree_code code
)
5737 return (flag_strong_eval_order
> 1 ? -1 : 0);
5741 return (flag_strong_eval_order
> 1 ? 1 : 0);
5744 // Not overloadable (yet).
5746 // Only one argument.
5753 return (flag_strong_eval_order
? 1 : 0);
5761 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5762 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5763 tsubst_flags_t complain
)
5765 struct z_candidate
*candidates
= 0, *cand
;
5766 vec
<tree
, va_gc
> *arglist
;
5768 tree result
= NULL_TREE
;
5769 bool result_valid_p
= false;
5770 enum tree_code code2
= NOP_EXPR
;
5771 enum tree_code code_orig_arg1
= ERROR_MARK
;
5772 enum tree_code code_orig_arg2
= ERROR_MARK
;
5778 if (error_operand_p (arg1
)
5779 || error_operand_p (arg2
)
5780 || error_operand_p (arg3
))
5781 return error_mark_node
;
5783 bool ismodop
= code
== MODIFY_EXPR
;
5786 code2
= TREE_CODE (arg3
);
5789 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5791 arg1
= prep_operand (arg1
);
5793 bool memonly
= false;
5798 case VEC_DELETE_EXPR
:
5800 /* Use build_op_new_call and build_op_delete_call instead. */
5804 /* Use build_op_call instead. */
5807 case TRUTH_ORIF_EXPR
:
5808 case TRUTH_ANDIF_EXPR
:
5809 case TRUTH_AND_EXPR
:
5811 /* These are saved for the sake of warn_logical_operator. */
5812 code_orig_arg1
= TREE_CODE (arg1
);
5813 code_orig_arg2
= TREE_CODE (arg2
);
5821 /* These are saved for the sake of maybe_warn_bool_compare. */
5822 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5823 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5826 /* =, ->, [], () must be non-static member functions. */
5828 if (code2
!= NOP_EXPR
)
5840 arg2
= prep_operand (arg2
);
5841 arg3
= prep_operand (arg3
);
5843 if (code
== COND_EXPR
)
5844 /* Use build_conditional_expr instead. */
5846 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5847 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5850 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5851 arg2
= integer_zero_node
;
5853 vec_alloc (arglist
, 3);
5854 arglist
->quick_push (arg1
);
5855 if (arg2
!= NULL_TREE
)
5856 arglist
->quick_push (arg2
);
5857 if (arg3
!= NULL_TREE
)
5858 arglist
->quick_push (arg3
);
5860 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5861 p
= conversion_obstack_alloc (0);
5863 /* Add namespace-scope operators to the list of functions to
5867 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5868 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5869 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5870 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5871 flags
, &candidates
, complain
);
5876 args
[2] = NULL_TREE
;
5878 /* Add class-member operators to the candidate set. */
5879 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5883 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5884 if (fns
== error_mark_node
)
5886 result
= error_mark_node
;
5887 goto user_defined_result_ready
;
5890 add_candidates (BASELINK_FUNCTIONS (fns
),
5891 NULL_TREE
, arglist
, NULL_TREE
,
5893 BASELINK_BINFO (fns
),
5894 BASELINK_ACCESS_BINFO (fns
),
5895 flags
, &candidates
, complain
);
5897 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5898 only non-member functions that have type T1 or reference to
5899 cv-qualified-opt T1 for the first argument, if the first argument
5900 has an enumeration type, or T2 or reference to cv-qualified-opt
5901 T2 for the second argument, if the second argument has an
5902 enumeration type. Filter out those that don't match. */
5903 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5905 struct z_candidate
**candp
, **next
;
5907 for (candp
= &candidates
; *candp
; candp
= next
)
5909 tree parmlist
, parmtype
;
5910 int i
, nargs
= (arg2
? 2 : 1);
5915 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5917 for (i
= 0; i
< nargs
; ++i
)
5919 parmtype
= TREE_VALUE (parmlist
);
5921 if (TYPE_REF_P (parmtype
))
5922 parmtype
= TREE_TYPE (parmtype
);
5923 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5924 && (same_type_ignoring_top_level_qualifiers_p
5925 (TREE_TYPE (args
[i
]), parmtype
)))
5928 parmlist
= TREE_CHAIN (parmlist
);
5931 /* No argument has an appropriate type, so remove this
5932 candidate function from the list. */
5935 *candp
= cand
->next
;
5941 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5948 /* For these, the built-in candidates set is empty
5949 [over.match.oper]/3. We don't want non-strict matches
5950 because exact matches are always possible with built-in
5951 operators. The built-in candidate set for COMPONENT_REF
5952 would be empty too, but since there are no such built-in
5953 operators, we accept non-strict matches for them. */
5962 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5967 case POSTINCREMENT_EXPR
:
5968 case POSTDECREMENT_EXPR
:
5969 /* Don't try anything fancy if we're not allowed to produce
5971 if (!(complain
& tf_error
))
5972 return error_mark_node
;
5974 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5975 distinguish between prefix and postfix ++ and
5976 operator++() was used for both, so we allow this with
5980 const char *msg
= (flag_permissive
)
5981 ? G_("no %<%D(int)%> declared for postfix %qs,"
5982 " trying prefix operator instead")
5983 : G_("no %<%D(int)%> declared for postfix %qs");
5984 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
5987 if (!flag_permissive
)
5988 return error_mark_node
;
5990 if (code
== POSTINCREMENT_EXPR
)
5991 code
= PREINCREMENT_EXPR
;
5993 code
= PREDECREMENT_EXPR
;
5994 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5995 NULL_TREE
, overload
, complain
);
5998 /* The caller will deal with these. */
6003 result_valid_p
= true;
6007 if (complain
& tf_error
)
6009 /* If one of the arguments of the operator represents
6010 an invalid use of member function pointer, try to report
6011 a meaningful error ... */
6012 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
6013 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
6014 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
6015 /* We displayed the error message. */;
6018 /* ... Otherwise, report the more generic
6019 "no matching operator found" error */
6020 auto_diagnostic_group d
;
6021 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
6022 print_z_candidates (loc
, candidates
);
6025 result
= error_mark_node
;
6031 cand
= tourney (candidates
, complain
);
6034 if (complain
& tf_error
)
6036 auto_diagnostic_group d
;
6037 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
6038 print_z_candidates (loc
, candidates
);
6040 result
= error_mark_node
;
6042 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
6045 *overload
= cand
->fn
;
6047 if (resolve_args (arglist
, complain
) == NULL
)
6048 result
= error_mark_node
;
6050 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6052 if (trivial_fn_p (cand
->fn
))
6053 /* There won't be a CALL_EXPR. */;
6054 else if (result
&& result
!= error_mark_node
)
6056 tree call
= extract_call_expr (result
);
6057 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
6059 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
6060 /* This prevents build_new_function_call from discarding this
6061 function during instantiation of the enclosing template. */
6062 KOENIG_LOOKUP_P (call
) = 1;
6064 /* Specify evaluation order as per P0145R2. */
6065 CALL_EXPR_ORDERED_ARGS (call
) = false;
6066 switch (op_is_ordered (code
))
6069 CALL_EXPR_REVERSE_ARGS (call
) = true;
6073 CALL_EXPR_ORDERED_ARGS (call
) = true;
6083 /* Give any warnings we noticed during overload resolution. */
6084 if (cand
->warnings
&& (complain
& tf_warning
))
6086 struct candidate_warning
*w
;
6087 for (w
= cand
->warnings
; w
; w
= w
->next
)
6088 joust (cand
, w
->loser
, 1, complain
);
6091 /* Check for comparison of different enum types. */
6100 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
6101 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
6102 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
6103 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
6104 && (complain
& tf_warning
))
6106 warning (OPT_Wenum_compare
,
6107 "comparison between %q#T and %q#T",
6108 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
6115 /* We need to strip any leading REF_BIND so that bitfields
6116 don't cause errors. This should not remove any important
6117 conversions, because builtins don't apply to class
6118 objects directly. */
6119 conv
= cand
->convs
[0];
6120 if (conv
->kind
== ck_ref_bind
)
6121 conv
= next_conversion (conv
);
6122 arg1
= convert_like (conv
, arg1
, complain
);
6126 conv
= cand
->convs
[1];
6127 if (conv
->kind
== ck_ref_bind
)
6128 conv
= next_conversion (conv
);
6130 arg2
= decay_conversion (arg2
, complain
);
6132 /* We need to call warn_logical_operator before
6133 converting arg2 to a boolean_type, but after
6134 decaying an enumerator to its value. */
6135 if (complain
& tf_warning
)
6136 warn_logical_operator (loc
, code
, boolean_type_node
,
6137 code_orig_arg1
, arg1
,
6138 code_orig_arg2
, arg2
);
6140 arg2
= convert_like (conv
, arg2
, complain
);
6144 conv
= cand
->convs
[2];
6145 if (conv
->kind
== ck_ref_bind
)
6146 conv
= next_conversion (conv
);
6147 arg3
= convert_like (conv
, arg3
, complain
);
6153 user_defined_result_ready
:
6155 /* Free all the conversions we allocated. */
6156 obstack_free (&conversion_obstack
, p
);
6158 if (result
|| result_valid_p
)
6165 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6168 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6170 case TRUTH_ANDIF_EXPR
:
6171 case TRUTH_ORIF_EXPR
:
6172 case TRUTH_AND_EXPR
:
6174 if (complain
& tf_warning
)
6175 warn_logical_operator (loc
, code
, boolean_type_node
,
6176 code_orig_arg1
, arg1
,
6177 code_orig_arg2
, arg2
);
6185 if ((complain
& tf_warning
)
6186 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6187 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6188 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6189 if (complain
& tf_warning
&& warn_tautological_compare
)
6190 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6195 case TRUNC_DIV_EXPR
:
6200 case TRUNC_MOD_EXPR
:
6204 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6206 case UNARY_PLUS_EXPR
:
6209 case TRUTH_NOT_EXPR
:
6210 case PREINCREMENT_EXPR
:
6211 case POSTINCREMENT_EXPR
:
6212 case PREDECREMENT_EXPR
:
6213 case POSTDECREMENT_EXPR
:
6217 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6220 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6223 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6227 /* The caller will deal with these. */
6239 /* Wrapper for above. */
6242 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6243 tree arg1
, tree arg2
, tree arg3
,
6244 tree
*overload
, tsubst_flags_t complain
)
6247 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6248 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6249 overload
, complain
);
6250 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6254 /* CALL was returned by some call-building function; extract the actual
6255 CALL_EXPR from any bits that have been tacked on, e.g. by
6256 convert_from_reference. */
6259 extract_call_expr (tree call
)
6261 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6262 call
= TREE_OPERAND (call
, 1);
6263 if (REFERENCE_REF_P (call
))
6264 call
= TREE_OPERAND (call
, 0);
6265 if (TREE_CODE (call
) == TARGET_EXPR
)
6266 call
= TARGET_EXPR_INITIAL (call
);
6267 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6268 || TREE_CODE (call
) == AGGR_INIT_EXPR
6269 || call
== error_mark_node
);
6273 /* Returns true if FN has two parameters, of which the second has type
6277 second_parm_is_size_t (tree fn
)
6279 tree t
= FUNCTION_ARG_CHAIN (fn
);
6280 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6283 if (t
== void_list_node
)
6285 if (aligned_new_threshold
&& t
6286 && same_type_p (TREE_VALUE (t
), align_type_node
)
6287 && TREE_CHAIN (t
) == void_list_node
)
6292 /* True if T, an allocation function, has std::align_val_t as its second
6296 aligned_allocation_fn_p (tree t
)
6298 if (!aligned_new_threshold
)
6301 tree a
= FUNCTION_ARG_CHAIN (t
);
6302 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6305 /* True if T is std::destroying_delete_t. */
6308 std_destroying_delete_t_p (tree t
)
6310 return (TYPE_CONTEXT (t
) == std_node
6311 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6314 /* A deallocation function with at least two parameters whose second parameter
6315 type is of type std::destroying_delete_t is a destroying operator delete. A
6316 destroying operator delete shall be a class member function named operator
6317 delete. [ Note: Array deletion cannot use a destroying operator
6318 delete. --end note ] */
6321 destroying_delete_p (tree t
)
6323 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6324 if (!a
|| !TREE_CHAIN (a
))
6326 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6327 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6330 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6331 function (3.7.4.2 [basic.stc.dynamic.deallocation]) with a parameter of
6332 std::align_val_t. */
6335 aligned_deallocation_fn_p (tree t
)
6337 if (!aligned_new_threshold
)
6340 /* A template instance is never a usual deallocation function,
6341 regardless of its signature. */
6342 if (TREE_CODE (t
) == TEMPLATE_DECL
6343 || primary_template_specialization_p (t
))
6346 tree a
= FUNCTION_ARG_CHAIN (t
);
6347 if (destroying_delete_p (t
))
6349 if (same_type_p (TREE_VALUE (a
), align_type_node
)
6350 && TREE_CHAIN (a
) == void_list_node
)
6352 if (!same_type_p (TREE_VALUE (a
), size_type_node
))
6355 if (a
&& same_type_p (TREE_VALUE (a
), align_type_node
)
6356 && TREE_CHAIN (a
) == void_list_node
)
6361 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
6362 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
6365 usual_deallocation_fn_p (tree t
)
6367 /* A template instance is never a usual deallocation function,
6368 regardless of its signature. */
6369 if (TREE_CODE (t
) == TEMPLATE_DECL
6370 || primary_template_specialization_p (t
))
6373 /* If a class T has a member deallocation function named operator delete
6374 with exactly one parameter, then that function is a usual
6375 (non-placement) deallocation function. If class T does not declare
6376 such an operator delete but does declare a member deallocation
6377 function named operator delete with exactly two parameters, the second
6378 of which has type std::size_t (18.2), then this function is a usual
6379 deallocation function. */
6380 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6381 tree chain
= FUNCTION_ARG_CHAIN (t
);
6384 if (destroying_delete_p (t
))
6385 chain
= TREE_CHAIN (chain
);
6386 if (chain
== void_list_node
6387 || ((!global
|| flag_sized_deallocation
)
6388 && second_parm_is_size_t (t
)))
6390 if (aligned_deallocation_fn_p (t
))
6395 /* Build a call to operator delete. This has to be handled very specially,
6396 because the restrictions on what signatures match are different from all
6397 other call instances. For a normal delete, only a delete taking (void *)
6398 or (void *, size_t) is accepted. For a placement delete, only an exact
6399 match with the placement new is accepted.
6401 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6402 ADDR is the pointer to be deleted.
6403 SIZE is the size of the memory block to be deleted.
6404 GLOBAL_P is true if the delete-expression should not consider
6405 class-specific delete operators.
6406 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6408 If this call to "operator delete" is being generated as part to
6409 deallocate memory allocated via a new-expression (as per [expr.new]
6410 which requires that if the initialization throws an exception then
6411 we call a deallocation function), then ALLOC_FN is the allocation
6415 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6416 bool global_p
, tree placement
,
6417 tree alloc_fn
, tsubst_flags_t complain
)
6419 tree fn
= NULL_TREE
;
6420 tree fns
, fnname
, type
, t
;
6422 if (addr
== error_mark_node
)
6423 return error_mark_node
;
6425 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6427 fnname
= ovl_op_identifier (false, code
);
6429 if (CLASS_TYPE_P (type
)
6430 && COMPLETE_TYPE_P (complete_type (type
))
6434 If the result of the lookup is ambiguous or inaccessible, or if
6435 the lookup selects a placement deallocation function, the
6436 program is ill-formed.
6438 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6440 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6441 if (fns
== error_mark_node
)
6442 return error_mark_node
;
6447 if (fns
== NULL_TREE
)
6448 fns
= lookup_name_nonclass (fnname
);
6450 /* Strip const and volatile from addr. */
6452 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6456 /* "A declaration of a placement deallocation function matches the
6457 declaration of a placement allocation function if it has the same
6458 number of parameters and, after parameter transformations (8.3.5),
6459 all parameter types except the first are identical."
6461 So we build up the function type we want and ask instantiate_type
6462 to get it for us. */
6463 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6464 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6465 t
= build_function_type (void_type_node
, t
);
6467 fn
= instantiate_type (t
, fns
, tf_none
);
6468 if (fn
== error_mark_node
)
6471 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6473 /* "If the lookup finds the two-parameter form of a usual deallocation
6474 function (3.7.4.2) and that function, considered as a placement
6475 deallocation function, would have been selected as a match for the
6476 allocation function, the program is ill-formed." */
6477 if (second_parm_is_size_t (fn
))
6479 const char *const msg1
6480 = G_("exception cleanup for this placement new selects "
6481 "non-placement operator delete");
6482 const char *const msg2
6483 = G_("%qD is a usual (non-placement) deallocation "
6484 "function in C++14 (or with -fsized-deallocation)");
6486 /* But if the class has an operator delete (void *), then that is
6487 the usual deallocation function, so we shouldn't complain
6488 about using the operator delete (void *, size_t). */
6489 if (DECL_CLASS_SCOPE_P (fn
))
6490 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6494 if (usual_deallocation_fn_p (elt
)
6495 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6498 /* Before C++14 a two-parameter global deallocation function is
6499 always a placement deallocation function, but warn if
6501 else if (!flag_sized_deallocation
)
6503 if (complain
& tf_warning
)
6505 auto_diagnostic_group d
;
6506 if (warning (OPT_Wc__14_compat
, msg1
))
6507 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6512 if (complain
& tf_warning_or_error
)
6514 auto_diagnostic_group d
;
6515 if (permerror (input_location
, msg1
))
6517 /* Only mention C++14 for namespace-scope delete. */
6518 if (DECL_NAMESPACE_SCOPE_P (fn
))
6519 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6521 inform (DECL_SOURCE_LOCATION (fn
),
6522 "%qD is a usual (non-placement) deallocation "
6527 return error_mark_node
;
6532 /* "Any non-placement deallocation function matches a non-placement
6533 allocation function. If the lookup finds a single matching
6534 deallocation function, that function will be called; otherwise, no
6535 deallocation function will be called." */
6536 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6539 if (usual_deallocation_fn_p (elt
))
6547 /* -- If any of the deallocation functions is a destroying
6548 operator delete, all deallocation functions that are not
6549 destroying operator deletes are eliminated from further
6551 bool fn_destroying
= destroying_delete_p (fn
);
6552 bool elt_destroying
= destroying_delete_p (elt
);
6553 if (elt_destroying
!= fn_destroying
)
6560 /* -- If the type has new-extended alignment, a function with a
6561 parameter of type std::align_val_t is preferred; otherwise a
6562 function without such a parameter is preferred. If exactly one
6563 preferred function is found, that function is selected and the
6564 selection process terminates. If more than one preferred
6565 function is found, all non-preferred functions are eliminated
6566 from further consideration. */
6567 if (aligned_new_threshold
)
6569 bool want_align
= type_has_new_extended_alignment (type
);
6570 bool fn_align
= aligned_deallocation_fn_p (fn
);
6571 bool elt_align
= aligned_deallocation_fn_p (elt
);
6573 if (elt_align
!= fn_align
)
6575 if (want_align
== elt_align
)
6581 /* -- If the deallocation functions have class scope, the one
6582 without a parameter of type std::size_t is selected. */
6584 if (DECL_CLASS_SCOPE_P (fn
))
6587 /* -- If the type is complete and if, for the second alternative
6588 (delete array) only, the operand is a pointer to a class type
6589 with a non-trivial destructor or a (possibly multi-dimensional)
6590 array thereof, the function with a parameter of type std::size_t
6593 -- Otherwise, it is unspecified whether a deallocation function
6594 with a parameter of type std::size_t is selected. */
6597 want_size
= COMPLETE_TYPE_P (type
);
6598 if (code
== VEC_DELETE_EXPR
6599 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6600 /* We need a cookie to determine the array size. */
6603 bool fn_size
= second_parm_is_size_t (fn
);
6604 bool elt_size
= second_parm_is_size_t (elt
);
6605 gcc_assert (fn_size
!= elt_size
);
6606 if (want_size
== elt_size
)
6611 /* If we have a matching function, call it. */
6614 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6616 /* If the FN is a member function, make sure that it is
6618 if (BASELINK_P (fns
))
6619 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6622 /* Core issue 901: It's ok to new a type with deleted delete. */
6623 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6628 /* The placement args might not be suitable for overload
6629 resolution at this point, so build the call directly. */
6630 int nargs
= call_expr_nargs (placement
);
6631 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6634 for (i
= 1; i
< nargs
; i
++)
6635 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6636 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6637 return error_mark_node
;
6638 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6642 tree destroying
= destroying_delete_p (fn
);
6645 /* Strip const and volatile from addr but retain the type of the
6647 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6648 rtype
= cv_unqualified (rtype
);
6649 rtype
= TYPE_POINTER_TO (rtype
);
6650 addr
= cp_convert (rtype
, oaddr
, complain
);
6651 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6656 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6657 args
->quick_push (addr
);
6659 args
->quick_push (destroying
);
6660 if (second_parm_is_size_t (fn
))
6661 args
->quick_push (size
);
6662 if (aligned_deallocation_fn_p (fn
))
6664 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6665 args
->quick_push (al
);
6667 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6668 release_tree_vector (args
);
6675 If no unambiguous matching deallocation function can be found,
6676 propagating the exception does not cause the object's memory to
6680 if ((complain
& tf_warning
)
6682 warning (0, "no corresponding deallocation function for %qD",
6687 if (complain
& tf_error
)
6688 error ("no suitable %<operator %s%> for %qT",
6689 OVL_OP_INFO (false, code
)->name
, type
);
6690 return error_mark_node
;
6693 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6696 If ISSUE_ERROR is true, then issue an error about the
6697 access, followed by a note showing the declaration.
6698 Otherwise, just show the note. */
6701 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6703 if (TREE_PRIVATE (decl
))
6706 error ("%q#D is private within this context", diag_decl
);
6707 inform (DECL_SOURCE_LOCATION (diag_decl
),
6708 "declared private here");
6710 else if (TREE_PROTECTED (decl
))
6713 error ("%q#D is protected within this context", diag_decl
);
6714 inform (DECL_SOURCE_LOCATION (diag_decl
),
6715 "declared protected here");
6720 error ("%q#D is inaccessible within this context", diag_decl
);
6721 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6725 /* If the current scope isn't allowed to access DECL along
6726 BASETYPE_PATH, give an error. The most derived class in
6727 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6728 the declaration to use in the error diagnostic. */
6731 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6732 tsubst_flags_t complain
, access_failure_info
*afi
)
6734 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6736 if (flag_new_inheriting_ctors
6737 && DECL_INHERITED_CTOR (decl
))
6739 /* 7.3.3/18: The additional constructors are accessible if they would be
6740 accessible when used to construct an object of the corresponding base
6742 decl
= strip_inheriting_ctors (decl
);
6743 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6744 ba_any
, NULL
, complain
);
6747 if (!accessible_p (basetype_path
, decl
, true))
6749 if (flag_new_inheriting_ctors
)
6750 diag_decl
= strip_inheriting_ctors (diag_decl
);
6751 if (complain
& tf_error
)
6752 complain_about_access (decl
, diag_decl
, true);
6754 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6761 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6762 bitwise or of LOOKUP_* values. If any errors are warnings are
6763 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6764 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6768 build_temp (tree expr
, tree type
, int flags
,
6769 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6772 vec
<tree
, va_gc
> *args
;
6774 *diagnostic_kind
= DK_UNSPECIFIED
;
6776 /* If the source is a packed field, calling the copy constructor will require
6777 binding the field to the reference parameter to the copy constructor, and
6778 we'll end up with an infinite loop. If we can use a bitwise copy, then
6780 if ((lvalue_kind (expr
) & clk_packed
)
6781 && CLASS_TYPE_P (TREE_TYPE (expr
))
6782 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6783 return get_target_expr_sfinae (expr
, complain
);
6785 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6786 args
= make_tree_vector_single (expr
);
6787 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6788 &args
, type
, flags
, complain
);
6789 release_tree_vector (args
);
6790 if (warningcount
+ werrorcount
> savew
)
6791 *diagnostic_kind
= DK_WARNING
;
6792 else if (errorcount
> savee
)
6793 *diagnostic_kind
= DK_ERROR
;
6797 /* Get any location for EXPR, falling back to input_location.
6799 If the result is in a system header and is the virtual location for
6800 a token coming from the expansion of a macro, unwind it to the
6801 location of the expansion point of the macro (e.g. to avoid the
6802 diagnostic being suppressed for expansions of NULL where "NULL" is
6803 in a system header). */
6806 get_location_for_expr_unwinding_for_system_header (tree expr
)
6808 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6809 loc
= expansion_point_location_if_in_system_header (loc
);
6813 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6814 Also handle a subset of zero as null warnings.
6815 EXPR is implicitly converted to type TOTYPE.
6816 FN and ARGNUM are used for diagnostics. */
6819 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6821 /* Issue warnings about peculiar, but valid, uses of NULL. */
6822 if (null_node_p (expr
) && TREE_CODE (totype
) != BOOLEAN_TYPE
6823 && ARITHMETIC_TYPE_P (totype
))
6825 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6828 auto_diagnostic_group d
;
6829 if (warning_at (loc
, OPT_Wconversion_null
,
6830 "passing NULL to non-pointer argument %P of %qD",
6832 inform (get_fndecl_argument_location (fn
, argnum
),
6836 warning_at (loc
, OPT_Wconversion_null
,
6837 "converting to non-pointer type %qT from NULL", totype
);
6840 /* Issue warnings if "false" is converted to a NULL pointer */
6841 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6842 && TYPE_PTR_P (totype
))
6844 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6847 auto_diagnostic_group d
;
6848 if (warning_at (loc
, OPT_Wconversion_null
,
6849 "converting %<false%> to pointer type for argument "
6850 "%P of %qD", argnum
, fn
))
6851 inform (get_fndecl_argument_location (fn
, argnum
),
6855 warning_at (loc
, OPT_Wconversion_null
,
6856 "converting %<false%> to pointer type %qT", totype
);
6858 /* Handle zero as null pointer warnings for cases other
6859 than EQ_EXPR and NE_EXPR */
6860 else if (null_ptr_cst_p (expr
) &&
6861 (TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
)))
6863 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6864 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6868 /* We gave a diagnostic during a conversion. If this was in the second
6869 standard conversion sequence of a user-defined conversion sequence, say
6870 which user-defined conversion. */
6873 maybe_print_user_conv_context (conversion
*convs
)
6875 if (convs
->user_conv_p
)
6876 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6877 if (t
->kind
== ck_user
)
6879 print_z_candidate (0, " after user-defined conversion:",
6885 /* Locate the parameter with the given index within FNDECL.
6886 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6887 Return the location of the FNDECL itself if there are problems. */
6890 get_fndecl_argument_location (tree fndecl
, int argnum
)
6892 /* The locations of implicitly-declared functions are likely to be
6893 more meaningful than those of their parameters. */
6894 if (DECL_ARTIFICIAL (fndecl
))
6895 return DECL_SOURCE_LOCATION (fndecl
);
6900 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6901 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6902 i
< argnum
&& param
;
6903 i
++, param
= TREE_CHAIN (param
))
6906 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6907 return the location of FNDECL. */
6909 return DECL_SOURCE_LOCATION (fndecl
);
6911 return DECL_SOURCE_LOCATION (param
);
6914 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6915 within its declaration (or the fndecl itself if something went
6919 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6922 inform (get_fndecl_argument_location (fn
, argnum
),
6923 " initializing argument %P of %qD", argnum
, fn
);
6926 /* Perform the conversions in CONVS on the expression EXPR. FN and
6927 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6928 indicates the `this' argument of a method. INNER is nonzero when
6929 being called to continue a conversion chain. It is negative when a
6930 reference binding will be applied, positive otherwise. If
6931 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6932 conversions will be emitted if appropriate. If C_CAST_P is true,
6933 this conversion is coming from a C-style cast; in that case,
6934 conversions to inaccessible bases are permitted. */
6937 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6938 bool issue_conversion_warnings
,
6939 bool c_cast_p
, tsubst_flags_t complain
)
6941 tree totype
= convs
->type
;
6942 diagnostic_t diag_kind
;
6944 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
6946 if (convs
->bad_p
&& !(complain
& tf_error
))
6947 return error_mark_node
;
6950 && convs
->kind
!= ck_user
6951 && convs
->kind
!= ck_list
6952 && convs
->kind
!= ck_ambig
6953 && (convs
->kind
!= ck_ref_bind
6954 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6955 && (convs
->kind
!= ck_rvalue
6956 || SCALAR_TYPE_P (totype
))
6957 && convs
->kind
!= ck_base
)
6959 bool complained
= false;
6960 conversion
*t
= convs
;
6962 /* Give a helpful error if this is bad because of excess braces. */
6963 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6964 && SCALAR_TYPE_P (totype
)
6965 && CONSTRUCTOR_NELTS (expr
) > 0
6966 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6968 complained
= permerror (loc
, "too many braces around initializer "
6970 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6971 && CONSTRUCTOR_NELTS (expr
) == 1)
6972 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6975 /* Give a helpful error if this is bad because a conversion to bool
6976 from std::nullptr_t requires direct-initialization. */
6977 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6978 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6979 complained
= permerror (loc
, "converting to %qH from %qI requires "
6980 "direct-initialization",
6981 totype
, TREE_TYPE (expr
));
6983 for (; t
; t
= next_conversion (t
))
6985 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6987 auto_diagnostic_group d
;
6988 complained
= permerror (loc
, "invalid user-defined conversion "
6989 "from %qH to %qI", TREE_TYPE (expr
),
6992 print_z_candidate (loc
, "candidate is:", t
->cand
);
6993 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6994 /*issue_conversion_warnings=*/false,
6997 if (convs
->kind
== ck_ref_bind
)
6998 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6999 LOOKUP_NORMAL
, NULL_TREE
,
7002 expr
= cp_convert (totype
, expr
, complain
);
7004 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7007 else if (t
->kind
== ck_user
|| !t
->bad_p
)
7009 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7010 /*issue_conversion_warnings=*/false,
7015 else if (t
->kind
== ck_ambig
)
7016 return convert_like_real (t
, expr
, fn
, argnum
,
7017 /*issue_conversion_warnings=*/false,
7020 else if (t
->kind
== ck_identity
)
7025 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
7026 gcc_rich_location
richloc (loc
, &label
);
7027 complained
= permerror (&richloc
,
7028 "invalid conversion from %qH to %qI",
7029 TREE_TYPE (expr
), totype
);
7032 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7034 return cp_convert (totype
, expr
, complain
);
7037 if (issue_conversion_warnings
&& (complain
& tf_warning
))
7038 conversion_null_warnings (totype
, expr
, fn
, argnum
);
7040 switch (convs
->kind
)
7044 struct z_candidate
*cand
= convs
->cand
;
7047 /* We chose the surrogate function from add_conv_candidate, now we
7048 actually need to build the conversion. */
7049 cand
= build_user_type_conversion_1 (totype
, expr
,
7050 LOOKUP_NO_CONVERSION
, complain
);
7052 tree convfn
= cand
->fn
;
7054 /* When converting from an init list we consider explicit
7055 constructors, but actually trying to call one is an error. */
7056 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
7057 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
7058 /* Unless this is for direct-list-initialization. */
7059 && (!CONSTRUCTOR_IS_DIRECT_INIT (expr
) || convs
->need_temporary_p
)
7060 /* And in C++98 a default constructor can't be explicit. */
7061 && cxx_dialect
>= cxx11
)
7063 if (!(complain
& tf_error
))
7064 return error_mark_node
;
7065 location_t loc
= location_of (expr
);
7066 if (CONSTRUCTOR_NELTS (expr
) == 0
7067 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
7069 auto_diagnostic_group d
;
7070 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
7071 "would use explicit constructor %qD",
7073 inform (loc
, "in C++11 and above a default constructor "
7077 error ("converting to %qT from initializer list would use "
7078 "explicit constructor %qD", totype
, convfn
);
7081 /* If we're initializing from {}, it's value-initialization. */
7082 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7083 && CONSTRUCTOR_NELTS (expr
) == 0
7084 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
)
7085 && !processing_template_decl
)
7087 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
7088 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
7089 return error_mark_node
;
7090 expr
= build_value_init (totype
, complain
);
7091 expr
= get_target_expr_sfinae (expr
, complain
);
7092 if (expr
!= error_mark_node
)
7094 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7095 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
7100 /* We don't know here whether EXPR is being used as an lvalue or
7101 rvalue, but we know it's read. */
7102 mark_exp_read (expr
);
7104 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
7106 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
7109 /* If this is a constructor or a function returning an aggr type,
7110 we need to build up a TARGET_EXPR. */
7111 if (DECL_CONSTRUCTOR_P (convfn
))
7113 expr
= build_cplus_new (totype
, expr
, complain
);
7115 /* Remember that this was list-initialization. */
7116 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
7117 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7123 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
7125 int nelts
= CONSTRUCTOR_NELTS (expr
);
7127 expr
= build_value_init (totype
, complain
);
7128 else if (nelts
== 1)
7129 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7133 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7134 /*read_p=*/true, UNKNOWN_LOCATION
,
7135 /*reject_builtin=*/true);
7137 if (type_unknown_p (expr
))
7138 expr
= instantiate_type (totype
, expr
, complain
);
7139 if (expr
== null_node
7140 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7141 /* If __null has been converted to an integer type, we do not want to
7142 continue to warn about uses of EXPR as an integer, rather than as a
7144 expr
= build_int_cst (totype
, 0);
7147 /* We leave bad_p off ck_ambig because overload resolution considers
7148 it valid, it just fails when we try to perform it. So we need to
7149 check complain here, too. */
7150 if (complain
& tf_error
)
7152 /* Call build_user_type_conversion again for the error. */
7153 int flags
= (convs
->need_temporary_p
7154 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7155 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7156 gcc_assert (seen_error ());
7157 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7159 return error_mark_node
;
7163 /* Conversion to std::initializer_list<T>. */
7164 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7165 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7170 tree val
; unsigned ix
;
7172 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7174 /* Convert all the elements. */
7175 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7177 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
,
7178 argnum
, false, false, complain
);
7179 if (sub
== error_mark_node
)
7181 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7182 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7183 return error_mark_node
;
7184 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
),
7186 if (!TREE_CONSTANT (sub
))
7187 TREE_CONSTANT (new_ctor
) = false;
7189 /* Build up the array. */
7190 elttype
= cp_build_qualified_type
7191 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7192 array
= build_array_of_n_type (elttype
, len
);
7193 array
= finish_compound_literal (array
, new_ctor
, complain
);
7194 /* Take the address explicitly rather than via decay_conversion
7195 to avoid the error about taking the address of a temporary. */
7196 array
= cp_build_addr_expr (array
, complain
);
7199 array
= nullptr_node
;
7201 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7202 if (array
== error_mark_node
)
7203 return error_mark_node
;
7205 /* Build up the initializer_list object. Note: fail gracefully
7206 if the object cannot be completed because, for example, no
7207 definition is provided (c++/80956). */
7208 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7210 return error_mark_node
;
7211 tree field
= next_initializable_field (TYPE_FIELDS (totype
));
7212 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7213 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7214 field
= next_initializable_field (DECL_CHAIN (field
));
7215 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7216 tree new_ctor
= build_constructor (totype
, vec
);
7217 return get_target_expr_sfinae (new_ctor
, complain
);
7221 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7223 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7224 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7225 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7227 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7229 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7232 expr
= reshape_init (totype
, expr
, complain
);
7233 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7235 if (expr
!= error_mark_node
)
7236 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7243 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7244 convs
->kind
== ck_ref_bind
7245 ? issue_conversion_warnings
: false,
7246 c_cast_p
, complain
);
7247 if (expr
== error_mark_node
)
7248 return error_mark_node
;
7250 switch (convs
->kind
)
7253 expr
= decay_conversion (expr
, complain
);
7254 if (expr
== error_mark_node
)
7256 if (complain
& tf_error
)
7258 auto_diagnostic_group d
;
7259 maybe_print_user_conv_context (convs
);
7260 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7262 return error_mark_node
;
7265 if (! MAYBE_CLASS_TYPE_P (totype
))
7268 /* Don't introduce copies when passing arguments along to the inherited
7270 if (current_function_decl
7271 && flag_new_inheriting_ctors
7272 && DECL_INHERITED_CTOR (current_function_decl
))
7275 if (TREE_CODE (expr
) == TARGET_EXPR
7276 && TARGET_EXPR_LIST_INIT_P (expr
))
7277 /* Copy-list-initialization doesn't actually involve a copy. */
7282 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7284 /* We are going to bind a reference directly to a base-class
7285 subobject of EXPR. */
7286 /* Build an expression for `*((base*) &expr)'. */
7287 expr
= convert_to_base (expr
, totype
,
7288 !c_cast_p
, /*nonnull=*/true, complain
);
7292 /* Copy-initialization where the cv-unqualified version of the source
7293 type is the same class as, or a derived class of, the class of the
7294 destination [is treated as direct-initialization]. [dcl.init] */
7295 flags
= LOOKUP_NORMAL
;
7296 if (convs
->user_conv_p
)
7297 /* This conversion is being done in the context of a user-defined
7298 conversion (i.e. the second step of copy-initialization), so
7299 don't allow any more. */
7300 flags
|= LOOKUP_NO_CONVERSION
;
7302 flags
|= LOOKUP_ONLYCONVERTING
;
7303 if (convs
->rvaluedness_matches_p
)
7304 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7305 flags
|= LOOKUP_PREFER_RVALUE
;
7306 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7307 if (diag_kind
&& complain
)
7309 auto_diagnostic_group d
;
7310 maybe_print_user_conv_context (convs
);
7311 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7314 return build_cplus_new (totype
, expr
, complain
);
7318 tree ref_type
= totype
;
7320 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7322 tree extype
= TREE_TYPE (expr
);
7323 auto_diagnostic_group d
;
7324 if (TYPE_REF_IS_RVALUE (ref_type
)
7326 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7327 "lvalue of type %qI", totype
, extype
);
7328 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7329 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7330 error_at (loc
, "cannot bind non-const lvalue reference of "
7331 "type %qH to an rvalue of type %qI", totype
, extype
);
7332 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7333 error_at (loc
, "binding reference of type %qH to %qI "
7334 "discards qualifiers", totype
, extype
);
7337 maybe_print_user_conv_context (convs
);
7338 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7340 return error_mark_node
;
7343 /* If necessary, create a temporary.
7345 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7346 that need temporaries, even when their types are reference
7347 compatible with the type of reference being bound, so the
7348 upcoming call to cp_build_addr_expr doesn't fail. */
7349 if (convs
->need_temporary_p
7350 || TREE_CODE (expr
) == CONSTRUCTOR
7351 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7353 /* Otherwise, a temporary of type "cv1 T1" is created and
7354 initialized from the initializer expression using the rules
7355 for a non-reference copy-initialization (8.5). */
7357 tree type
= TREE_TYPE (ref_type
);
7358 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7360 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7361 (type
, next_conversion (convs
)->type
));
7362 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7363 && !TYPE_REF_IS_RVALUE (ref_type
))
7365 /* If the reference is volatile or non-const, we
7366 cannot create a temporary. */
7367 if (lvalue
& clk_bitfield
)
7368 error_at (loc
, "cannot bind bitfield %qE to %qT",
7370 else if (lvalue
& clk_packed
)
7371 error_at (loc
, "cannot bind packed field %qE to %qT",
7374 error_at (loc
, "cannot bind rvalue %qE to %qT",
7376 return error_mark_node
;
7378 /* If the source is a packed field, and we must use a copy
7379 constructor, then building the target expr will require
7380 binding the field to the reference parameter to the
7381 copy constructor, and we'll end up with an infinite
7382 loop. If we can use a bitwise copy, then we'll be
7384 if ((lvalue
& clk_packed
)
7385 && CLASS_TYPE_P (type
)
7386 && type_has_nontrivial_copy_init (type
))
7388 error_at (loc
, "cannot bind packed field %qE to %qT",
7390 return error_mark_node
;
7392 if (lvalue
& clk_bitfield
)
7394 expr
= convert_bitfield_to_declared_type (expr
);
7395 expr
= fold_convert (type
, expr
);
7397 expr
= build_target_expr_with_type (expr
, type
, complain
);
7400 /* Take the address of the thing to which we will bind the
7402 expr
= cp_build_addr_expr (expr
, complain
);
7403 if (expr
== error_mark_node
)
7404 return error_mark_node
;
7406 /* Convert it to a pointer to the type referred to by the
7407 reference. This will adjust the pointer if a derived to
7408 base conversion is being performed. */
7409 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7411 /* Convert the pointer to the desired reference type. */
7412 return build_nop (ref_type
, expr
);
7416 return decay_conversion (expr
, complain
);
7419 /* ??? Should the address of a transaction-safe pointer point to the TM
7420 clone, and this conversion look up the primary function? */
7421 return build_nop (totype
, expr
);
7424 /* Warn about deprecated conversion if appropriate. */
7425 string_conv_p (totype
, expr
, 1);
7430 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7431 /*nonnull=*/false, complain
);
7432 return build_nop (totype
, expr
);
7435 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7436 c_cast_p
, complain
);
7442 if (convs
->check_narrowing
7443 && !check_narrowing (totype
, expr
, complain
,
7444 convs
->check_narrowing_const_only
))
7445 return error_mark_node
;
7447 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7448 if (issue_conversion_warnings
)
7449 expr
= cp_convert_and_check (totype
, expr
, complain
);
7451 expr
= cp_convert (totype
, expr
, complain
);
7456 /* ARG is being passed to a varargs function. Perform any conversions
7457 required. Return the converted value. */
7460 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7463 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
7467 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7468 standard conversions are performed. */
7469 arg
= decay_conversion (arg
, complain
);
7470 arg_type
= TREE_TYPE (arg
);
7473 If the argument has integral or enumeration type that is subject
7474 to the integral promotions (_conv.prom_), or a floating point
7475 type that is subject to the floating point promotion
7476 (_conv.fpprom_), the value of the argument is converted to the
7477 promoted type before the call. */
7478 if (TREE_CODE (arg_type
) == REAL_TYPE
7479 && (TYPE_PRECISION (arg_type
)
7480 < TYPE_PRECISION (double_type_node
))
7481 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7483 if ((complain
& tf_warning
)
7484 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7485 warning_at (loc
, OPT_Wdouble_promotion
,
7486 "implicit conversion from %qH to %qI when passing "
7487 "argument to function",
7488 arg_type
, double_type_node
);
7489 arg
= convert_to_real_nofold (double_type_node
, arg
);
7491 else if (NULLPTR_TYPE_P (arg_type
))
7492 arg
= null_pointer_node
;
7493 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7495 if (SCOPED_ENUM_P (arg_type
))
7497 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7499 prom
= cp_perform_integral_promotions (prom
, complain
);
7500 if (abi_version_crosses (6)
7501 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7502 && (complain
& tf_warning
))
7503 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
7504 "%qT before %<-fabi-version=6%>, %qT after", arg_type
,
7505 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7506 if (!abi_version_at_least (6))
7510 arg
= cp_perform_integral_promotions (arg
, complain
);
7513 arg
= require_complete_type_sfinae (arg
, complain
);
7514 arg_type
= TREE_TYPE (arg
);
7516 if (arg
!= error_mark_node
7517 /* In a template (or ill-formed code), we can have an incomplete type
7518 even after require_complete_type_sfinae, in which case we don't know
7519 whether it has trivial copy or not. */
7520 && COMPLETE_TYPE_P (arg_type
)
7521 && !cp_unevaluated_operand
)
7523 /* [expr.call] 5.2.2/7:
7524 Passing a potentially-evaluated argument of class type (Clause 9)
7525 with a non-trivial copy constructor or a non-trivial destructor
7526 with no corresponding parameter is conditionally-supported, with
7527 implementation-defined semantics.
7529 We support it as pass-by-invisible-reference, just like a normal
7532 If the call appears in the context of a sizeof expression,
7533 it is not potentially-evaluated. */
7534 if (type_has_nontrivial_copy_init (arg_type
)
7535 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7537 arg
= force_rvalue (arg
, complain
);
7538 if (complain
& tf_warning
)
7539 warning (OPT_Wconditionally_supported
,
7540 "passing objects of non-trivially-copyable "
7541 "type %q#T through %<...%> is conditionally supported",
7543 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7545 /* Build up a real lvalue-to-rvalue conversion in case the
7546 copy constructor is trivial but not callable. */
7547 else if (CLASS_TYPE_P (arg_type
))
7548 force_rvalue (arg
, complain
);
7555 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7558 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7560 if (processing_template_decl
)
7562 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7563 SET_EXPR_LOCATION (r
, loc
);
7567 type
= complete_type_or_else (type
, NULL_TREE
);
7569 if (expr
== error_mark_node
|| !type
)
7570 return error_mark_node
;
7572 expr
= mark_lvalue_use (expr
);
7574 if (TYPE_REF_P (type
))
7576 error ("cannot receive reference type %qT through %<...%>", type
);
7577 return error_mark_node
;
7580 if (type_has_nontrivial_copy_init (type
)
7581 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7583 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7584 it as pass by invisible reference. */
7585 warning_at (loc
, OPT_Wconditionally_supported
,
7586 "receiving objects of non-trivially-copyable type %q#T "
7587 "through %<...%> is conditionally-supported", type
);
7589 tree ref
= cp_build_reference_type (type
, false);
7590 expr
= build_va_arg (loc
, expr
, ref
);
7591 return convert_from_reference (expr
);
7594 tree ret
= build_va_arg (loc
, expr
, type
);
7595 if (CLASS_TYPE_P (type
))
7596 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7597 know how to handle it. */
7598 ret
= get_target_expr (ret
);
7602 /* TYPE has been given to va_arg. Apply the default conversions which
7603 would have happened when passed via ellipsis. Return the promoted
7604 type, or the passed type if there is no change. */
7607 cxx_type_promotes_to (tree type
)
7611 /* Perform the array-to-pointer and function-to-pointer
7613 type
= type_decays_to (type
);
7615 promote
= type_promotes_to (type
);
7616 if (same_type_p (type
, promote
))
7622 /* ARG is a default argument expression being passed to a parameter of
7623 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7624 zero-based argument number. Do any required conversions. Return
7625 the converted value. */
7627 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7629 push_defarg_context (tree fn
)
7630 { vec_safe_push (default_arg_context
, fn
); }
7633 pop_defarg_context (void)
7634 { default_arg_context
->pop (); }
7637 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7638 tsubst_flags_t complain
)
7643 /* See through clones. */
7644 fn
= DECL_ORIGIN (fn
);
7645 /* And inheriting ctors. */
7646 if (flag_new_inheriting_ctors
)
7647 fn
= strip_inheriting_ctors (fn
);
7649 /* Detect recursion. */
7650 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7653 if (complain
& tf_error
)
7654 error ("recursive evaluation of default argument for %q#D", fn
);
7655 return error_mark_node
;
7658 /* If the ARG is an unparsed default argument expression, the
7659 conversion cannot be performed. */
7660 if (TREE_CODE (arg
) == DEFAULT_ARG
)
7662 if (complain
& tf_error
)
7663 error ("call to %qD uses the default argument for parameter %P, which "
7664 "is not yet defined", fn
, parmnum
);
7665 return error_mark_node
;
7668 push_defarg_context (fn
);
7670 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7671 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7677 The names in the expression are bound, and the semantic
7678 constraints are checked, at the point where the default
7679 expressions appears.
7681 we must not perform access checks here. */
7682 push_deferring_access_checks (dk_no_check
);
7683 /* We must make a copy of ARG, in case subsequent processing
7684 alters any part of it. */
7685 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7687 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7688 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7690 arg
= convert_for_arg_passing (type
, arg
, complain
);
7691 pop_deferring_access_checks();
7693 pop_defarg_context ();
7698 /* Returns the type which will really be used for passing an argument of
7702 type_passed_as (tree type
)
7704 /* Pass classes with copy ctors by invisible reference. */
7705 if (TREE_ADDRESSABLE (type
))
7707 type
= build_reference_type (type
);
7708 /* There are no other pointers to this temporary. */
7709 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7711 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7712 && INTEGRAL_TYPE_P (type
)
7713 && COMPLETE_TYPE_P (type
)
7714 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7715 type
= integer_type_node
;
7720 /* Actually perform the appropriate conversion. */
7723 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7727 /* If VAL is a bitfield, then -- since it has already been converted
7728 to TYPE -- it cannot have a precision greater than TYPE.
7730 If it has a smaller precision, we must widen it here. For
7731 example, passing "int f:3;" to a function expecting an "int" will
7732 not result in any conversion before this point.
7734 If the precision is the same we must not risk widening. For
7735 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7736 often have type "int", even though the C++ type for the field is
7737 "long long". If the value is being passed to a function
7738 expecting an "int", then no conversions will be required. But,
7739 if we call convert_bitfield_to_declared_type, the bitfield will
7740 be converted to "long long". */
7741 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7743 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7744 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7746 if (val
== error_mark_node
)
7748 /* Pass classes with copy ctors by invisible reference. */
7749 else if (TREE_ADDRESSABLE (type
))
7750 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7751 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7752 && INTEGRAL_TYPE_P (type
)
7753 && COMPLETE_TYPE_P (type
)
7754 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7755 val
= cp_perform_integral_promotions (val
, complain
);
7756 if (complain
& tf_warning
)
7758 if (warn_suggest_attribute_format
)
7760 tree rhstype
= TREE_TYPE (val
);
7761 const enum tree_code coder
= TREE_CODE (rhstype
);
7762 const enum tree_code codel
= TREE_CODE (type
);
7763 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7765 && check_missing_format_attribute (type
, rhstype
))
7766 warning (OPT_Wsuggest_attribute_format
,
7767 "argument of function call might be a candidate "
7768 "for a format attribute");
7770 maybe_warn_parm_abi (type
, cp_expr_loc_or_loc (val
, input_location
));
7773 if (complain
& tf_warning
)
7774 warn_for_address_or_pointer_of_packed_member (type
, val
);
7779 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7780 which just decay_conversion or no conversions at all should be done.
7781 This is true for some builtins which don't act like normal functions.
7782 Return 2 if no conversions at all should be done, 1 if just
7783 decay_conversion. Return 3 for special treatment of the 3rd argument
7784 for __builtin_*_overflow_p. */
7787 magic_varargs_p (tree fn
)
7789 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7790 switch (DECL_FUNCTION_CODE (fn
))
7792 case BUILT_IN_CLASSIFY_TYPE
:
7793 case BUILT_IN_CONSTANT_P
:
7794 case BUILT_IN_NEXT_ARG
:
7795 case BUILT_IN_VA_START
:
7798 case BUILT_IN_ADD_OVERFLOW_P
:
7799 case BUILT_IN_SUB_OVERFLOW_P
:
7800 case BUILT_IN_MUL_OVERFLOW_P
:
7804 return lookup_attribute ("type generic",
7805 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7811 /* Returns the decl of the dispatcher function if FN is a function version. */
7814 get_function_version_dispatcher (tree fn
)
7816 tree dispatcher_decl
= NULL
;
7818 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7819 && DECL_FUNCTION_VERSIONED (fn
));
7821 gcc_assert (targetm
.get_function_versions_dispatcher
);
7822 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7824 if (dispatcher_decl
== NULL
)
7826 error_at (input_location
, "use of multiversioned function "
7827 "without a default");
7831 retrofit_lang_decl (dispatcher_decl
);
7832 gcc_assert (dispatcher_decl
!= NULL
);
7833 return dispatcher_decl
;
7836 /* fn is a function version dispatcher that is marked used. Mark all the
7837 semantically identical function versions it will dispatch as used. */
7840 mark_versions_used (tree fn
)
7842 struct cgraph_node
*node
;
7843 struct cgraph_function_version_info
*node_v
;
7844 struct cgraph_function_version_info
*it_v
;
7846 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7848 node
= cgraph_node::get (fn
);
7852 gcc_assert (node
->dispatcher_function
);
7854 node_v
= node
->function_version ();
7858 /* All semantically identical versions are chained. Traverse and mark each
7859 one of them as used. */
7860 it_v
= node_v
->next
;
7861 while (it_v
!= NULL
)
7863 mark_used (it_v
->this_node
->decl
);
7868 /* Build a call to "the copy constructor" for the type of A, even if it
7869 wouldn't be selected by normal overload resolution. Used for
7873 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7875 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7876 tree binfo
= TYPE_BINFO (ctype
);
7877 tree copy
= get_copy_ctor (ctype
, complain
);
7878 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7879 tree ob
= build_dummy_object (ctype
);
7880 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7881 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7882 LOOKUP_NORMAL
, NULL
, complain
);
7883 release_tree_vector (args
);
7887 /* Return true iff T refers to a base field. */
7890 is_base_field_ref (tree t
)
7893 if (TREE_CODE (t
) == ADDR_EXPR
)
7894 t
= TREE_OPERAND (t
, 0);
7895 if (TREE_CODE (t
) == COMPONENT_REF
)
7896 t
= TREE_OPERAND (t
, 1);
7897 if (TREE_CODE (t
) == FIELD_DECL
)
7898 return DECL_FIELD_IS_BASE (t
);
7902 /* We can't elide a copy from a function returning by value to a base
7903 subobject, as the callee might clobber tail padding. Return true iff this
7904 could be that case. */
7907 unsafe_copy_elision_p (tree target
, tree exp
)
7909 /* Copy elision only happens with a TARGET_EXPR. */
7910 if (TREE_CODE (exp
) != TARGET_EXPR
)
7912 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7913 /* It's safe to elide the copy for a class with no tail padding. */
7914 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7916 /* It's safe to elide the copy if we aren't initializing a base object. */
7917 if (!is_base_field_ref (target
))
7919 tree init
= TARGET_EXPR_INITIAL (exp
);
7920 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7921 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7922 init
= TREE_OPERAND (init
, 1);
7923 if (TREE_CODE (init
) == COND_EXPR
)
7925 /* We'll end up copying from each of the arms of the COND_EXPR directly
7926 into the target, so look at them. */
7927 if (tree op
= TREE_OPERAND (init
, 1))
7928 if (unsafe_copy_elision_p (target
, op
))
7930 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7932 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7933 && !AGGR_INIT_VIA_CTOR_P (init
));
7936 /* True iff C is a conversion that binds a reference to a prvalue. */
7939 conv_binds_ref_to_prvalue (conversion
*c
)
7941 if (c
->kind
!= ck_ref_bind
)
7943 if (c
->need_temporary_p
)
7946 c
= next_conversion (c
);
7948 if (c
->kind
== ck_rvalue
)
7950 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7952 if (c
->kind
== ck_identity
&& c
->u
.expr
7953 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7959 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7960 class type or a pointer to class type. */
7963 build_trivial_dtor_call (tree instance
)
7965 gcc_assert (!is_dummy_object (instance
));
7967 if (!flag_lifetime_dse
)
7970 return fold_convert (void_type_node
, instance
);
7973 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
7975 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7977 instance
= cp_build_fold_indirect_ref (instance
);
7980 /* A trivial destructor should still clobber the object. */
7981 tree clobber
= build_clobber (TREE_TYPE (instance
));
7982 return build2 (MODIFY_EXPR
, void_type_node
,
7986 /* Subroutine of the various build_*_call functions. Overload resolution
7987 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7988 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7989 bitmask of various LOOKUP_* flags which apply to the call itself. */
7992 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7995 const vec
<tree
, va_gc
> *args
= cand
->args
;
7996 tree first_arg
= cand
->first_arg
;
7997 conversion
**convs
= cand
->convs
;
7999 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
8004 unsigned int arg_index
= 0;
8008 bool already_used
= false;
8010 /* In a template, there is no need to perform all of the work that
8011 is normally done. We are only interested in the type of the call
8012 expression, i.e., the return type of the function. Any semantic
8013 errors will be deferred until the template is instantiated. */
8014 if (processing_template_decl
)
8018 const tree
*argarray
;
8021 if (undeduced_auto_decl (fn
))
8022 mark_used (fn
, complain
);
8024 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
8028 return_type
= TREE_TYPE (TREE_TYPE (fn
));
8029 nargs
= vec_safe_length (args
);
8030 if (first_arg
== NULL_TREE
)
8031 argarray
= args
->address ();
8039 alcarray
= XALLOCAVEC (tree
, nargs
);
8040 alcarray
[0] = build_this (first_arg
);
8041 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
8042 alcarray
[ix
+ 1] = arg
;
8043 argarray
= alcarray
;
8046 addr
= build_addr_func (fn
, complain
);
8047 if (addr
== error_mark_node
)
8048 return error_mark_node
;
8049 expr
= build_call_array_loc (input_location
, return_type
,
8050 addr
, nargs
, argarray
);
8051 if (TREE_THIS_VOLATILE (fn
) && cfun
)
8052 current_function_returns_abnormally
= 1;
8053 return convert_from_reference (expr
);
8056 /* Give any warnings we noticed during overload resolution. */
8057 if (cand
->warnings
&& (complain
& tf_warning
))
8059 struct candidate_warning
*w
;
8060 for (w
= cand
->warnings
; w
; w
= w
->next
)
8061 joust (cand
, w
->loser
, 1, complain
);
8064 /* Core issue 2327: P0135 doesn't say how to handle the case where the
8065 argument to the copy constructor ends up being a prvalue after
8066 conversion. Let's do the normal processing, but pretend we aren't
8067 actually using the copy constructor. */
8068 bool force_elide
= false;
8069 if (cxx_dialect
>= cxx17
8070 && cand
->num_convs
== 1
8071 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
8072 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8073 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8074 && conv_binds_ref_to_prvalue (convs
[0]))
8077 goto not_really_used
;
8080 /* OK, we're actually calling this inherited constructor; set its deletedness
8081 appropriately. We can get away with doing this here because calling is
8082 the only way to refer to a constructor. */
8083 if (DECL_INHERITED_CTOR (fn
))
8084 deduce_inheriting_ctor (fn
);
8086 /* Make =delete work with SFINAE. */
8087 if (DECL_DELETED_FN (fn
))
8089 if (complain
& tf_error
)
8091 return error_mark_node
;
8094 if (DECL_FUNCTION_MEMBER_P (fn
))
8097 /* If FN is a template function, two cases must be considered.
8102 template <class T> void f();
8104 template <class T> struct B {
8108 struct C : A, B<int> {
8110 using B<int>::g; // #2
8113 In case #1 where `A::f' is a member template, DECL_ACCESS is
8114 recorded in the primary template but not in its specialization.
8115 We check access of FN using its primary template.
8117 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
8118 because it is a member of class template B, DECL_ACCESS is
8119 recorded in the specialization `B<int>::g'. We cannot use its
8120 primary template because `B<T>::g' and `B<int>::g' may have
8121 different access. */
8122 if (DECL_TEMPLATE_INFO (fn
)
8123 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
8124 access_fn
= DECL_TI_TEMPLATE (fn
);
8127 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
8129 return error_mark_node
;
8132 /* If we're checking for implicit delete, don't bother with argument
8134 if (flags
& LOOKUP_SPECULATIVE
)
8136 if (cand
->viable
== 1)
8138 else if (!(complain
& tf_error
))
8139 /* Reject bad conversions now. */
8140 return error_mark_node
;
8141 /* else continue to get conversion error. */
8146 /* N3276 magic doesn't apply to nested calls. */
8147 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8148 complain
&= ~tf_decltype
;
8149 /* No-Cleanup doesn't apply to nested calls either. */
8150 tsubst_flags_t no_cleanup_complain
= complain
;
8151 complain
&= ~tf_no_cleanup
;
8153 /* Find maximum size of vector to hold converted arguments. */
8154 parmlen
= list_length (parm
);
8155 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8156 if (parmlen
> nargs
)
8158 argarray
= XALLOCAVEC (tree
, nargs
);
8160 /* The implicit parameters to a constructor are not considered by overload
8161 resolution, and must be of the proper type. */
8162 if (DECL_CONSTRUCTOR_P (fn
))
8165 if (first_arg
!= NULL_TREE
)
8167 object_arg
= first_arg
;
8168 first_arg
= NULL_TREE
;
8172 object_arg
= (*args
)[arg_index
];
8175 argarray
[j
++] = build_this (object_arg
);
8176 parm
= TREE_CHAIN (parm
);
8177 /* We should never try to call the abstract constructor. */
8178 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8180 if (DECL_HAS_VTT_PARM_P (fn
))
8182 argarray
[j
++] = (*args
)[arg_index
];
8184 parm
= TREE_CHAIN (parm
);
8187 if (flags
& LOOKUP_PREFER_RVALUE
)
8189 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8190 the first parameter of the selected constructor is not an rvalue
8191 reference to the object's type (possibly cv-qualified)...." */
8192 gcc_assert (!(complain
& tf_error
));
8193 tree ptype
= convs
[0]->type
;
8194 if (!TYPE_REF_P (ptype
)
8195 || !TYPE_REF_IS_RVALUE (ptype
)
8196 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8197 return error_mark_node
;
8200 /* Bypass access control for 'this' parameter. */
8201 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8203 tree parmtype
= TREE_VALUE (parm
);
8204 tree arg
= build_this (first_arg
!= NULL_TREE
8206 : (*args
)[arg_index
]);
8207 tree argtype
= TREE_TYPE (arg
);
8211 if (arg
== error_mark_node
)
8212 return error_mark_node
;
8214 if (convs
[i
]->bad_p
)
8216 if (complain
& tf_error
)
8218 auto_diagnostic_group d
;
8219 if (permerror (input_location
, "passing %qT as %<this%> "
8220 "argument discards qualifiers",
8221 TREE_TYPE (argtype
)))
8222 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8225 return error_mark_node
;
8228 /* See if the function member or the whole class type is declared
8229 final and the call can be devirtualized. */
8230 if (DECL_FINAL_P (fn
)
8231 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
8232 flags
|= LOOKUP_NONVIRTUAL
;
8234 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8235 X is called for an object that is not of type X, or of a type
8236 derived from X, the behavior is undefined.
8238 So we can assume that anything passed as 'this' is non-null, and
8239 optimize accordingly. */
8240 gcc_assert (TYPE_PTR_P (parmtype
));
8241 /* Convert to the base in which the function was declared. */
8242 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8243 converted_arg
= build_base_path (PLUS_EXPR
,
8245 cand
->conversion_path
,
8247 /* Check that the base class is accessible. */
8248 if (!accessible_base_p (TREE_TYPE (argtype
),
8249 BINFO_TYPE (cand
->conversion_path
), true))
8251 if (complain
& tf_error
)
8252 error ("%qT is not an accessible base of %qT",
8253 BINFO_TYPE (cand
->conversion_path
),
8254 TREE_TYPE (argtype
));
8256 return error_mark_node
;
8258 /* If fn was found by a using declaration, the conversion path
8259 will be to the derived class, not the base declaring fn. We
8260 must convert from derived to base. */
8261 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8262 TREE_TYPE (parmtype
), ba_unique
,
8264 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8265 base_binfo
, 1, complain
);
8267 argarray
[j
++] = converted_arg
;
8268 parm
= TREE_CHAIN (parm
);
8269 if (first_arg
!= NULL_TREE
)
8270 first_arg
= NULL_TREE
;
8277 gcc_assert (first_arg
== NULL_TREE
);
8278 for (; arg_index
< vec_safe_length (args
) && parm
;
8279 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8281 tree type
= TREE_VALUE (parm
);
8282 tree arg
= (*args
)[arg_index
];
8283 bool conversion_warning
= true;
8287 /* If the argument is NULL and used to (implicitly) instantiate a
8288 template function (and bind one of the template arguments to
8289 the type of 'long int'), we don't want to warn about passing NULL
8290 to non-pointer argument.
8291 For example, if we have this template function:
8293 template<typename T> void func(T x) {}
8295 we want to warn (when -Wconversion is enabled) in this case:
8301 but not in this case:
8307 if (null_node_p (arg
)
8308 && DECL_TEMPLATE_INFO (fn
)
8309 && cand
->template_decl
8310 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8311 conversion_warning
= false;
8313 /* Warn about initializer_list deduction that isn't currently in the
8315 if (cxx_dialect
> cxx98
8316 && flag_deduce_init_list
8317 && cand
->template_decl
8318 && is_std_init_list (non_reference (type
))
8319 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
8321 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
8322 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
8323 tree patparm
= get_pattern_parm (realparm
, tmpl
);
8324 tree pattype
= TREE_TYPE (patparm
);
8325 if (PACK_EXPANSION_P (pattype
))
8326 pattype
= PACK_EXPANSION_PATTERN (pattype
);
8327 pattype
= non_reference (pattype
);
8329 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
8330 && (cand
->explicit_targs
== NULL_TREE
8331 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
8332 <= TEMPLATE_TYPE_IDX (pattype
))))
8334 pedwarn (input_location
, 0, "deducing %qT as %qT",
8335 non_reference (TREE_TYPE (patparm
)),
8336 non_reference (type
));
8337 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
8338 " in call to %qD", cand
->fn
);
8339 pedwarn (input_location
, 0,
8340 " (you can disable this with "
8341 "%<-fno-deduce-init-list%>)");
8345 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8346 knows not to allow any more UDCs. This needs to happen after we
8347 process cand->warnings. */
8348 if (flags
& LOOKUP_NO_CONVERSION
)
8349 conv
->user_conv_p
= true;
8351 tsubst_flags_t arg_complain
= complain
;
8352 if (!conversion_warning
)
8353 arg_complain
&= ~tf_warning
;
8355 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8357 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8359 if (val
== error_mark_node
)
8360 return error_mark_node
;
8362 argarray
[j
++] = val
;
8365 /* Default arguments */
8366 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8368 if (TREE_VALUE (parm
) == error_mark_node
)
8369 return error_mark_node
;
8370 val
= convert_default_arg (TREE_VALUE (parm
),
8371 TREE_PURPOSE (parm
),
8374 if (val
== error_mark_node
)
8375 return error_mark_node
;
8376 argarray
[j
++] = val
;
8380 int magic
= magic_varargs_p (fn
);
8381 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8383 tree a
= (*args
)[arg_index
];
8384 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8386 /* Do no conversions for certain magic varargs. */
8387 a
= mark_type_use (a
);
8388 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8389 return error_mark_node
;
8391 else if (magic
!= 0)
8392 /* For other magic varargs only do decay_conversion. */
8393 a
= decay_conversion (a
, complain
);
8394 else if (DECL_CONSTRUCTOR_P (fn
)
8395 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8398 /* Avoid infinite recursion trying to call A(...). */
8399 if (complain
& tf_error
)
8400 /* Try to call the actual copy constructor for a good error. */
8401 call_copy_ctor (a
, complain
);
8402 return error_mark_node
;
8405 a
= convert_arg_to_ellipsis (a
, complain
);
8406 if (a
== error_mark_node
)
8407 return error_mark_node
;
8411 gcc_assert (j
<= nargs
);
8414 /* Avoid to do argument-transformation, if warnings for format, and for
8415 nonnull are disabled. Just in case that at least one of them is active
8416 the check_function_arguments function might warn about something. */
8418 bool warned_p
= false;
8421 || warn_suggest_attribute_format
8424 tree
*fargs
= (!nargs
? argarray
8425 : (tree
*) alloca (nargs
* sizeof (tree
)));
8426 for (j
= 0; j
< nargs
; j
++)
8428 /* For -Wformat undo the implicit passing by hidden reference
8429 done by convert_arg_to_ellipsis. */
8430 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8431 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8432 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8434 fargs
[j
] = argarray
[j
];
8437 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8438 nargs
, fargs
, NULL
);
8441 if (DECL_INHERITED_CTOR (fn
))
8443 /* Check for passing ellipsis arguments to an inherited constructor. We
8444 could handle this by open-coding the inherited constructor rather than
8445 defining it, but let's not bother now. */
8446 if (!cp_unevaluated_operand
8448 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8450 if (complain
& tf_error
)
8452 sorry ("passing arguments to ellipsis of inherited constructor "
8454 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8456 return error_mark_node
;
8459 /* A base constructor inheriting from a virtual base doesn't get the
8460 inherited arguments, just this and __vtt. */
8461 if (ctor_omit_inherited_parms (fn
))
8465 /* Avoid actually calling copy constructors and copy assignment operators,
8468 if (! flag_elide_constructors
&& !force_elide
)
8469 /* Do things the hard way. */;
8470 else if (cand
->num_convs
== 1
8471 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8472 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8473 /* It's unsafe to elide the constructor when handling
8474 a noexcept-expression, it may evaluate to the wrong
8475 value (c++/53025). */
8476 && (force_elide
|| cp_noexcept_operand
== 0))
8479 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8481 bool trivial
= trivial_fn_p (fn
);
8483 /* Pull out the real argument, disregarding const-correctness. */
8485 /* Strip the reference binding for the constructor parameter. */
8486 if (CONVERT_EXPR_P (targ
)
8487 && TYPE_REF_P (TREE_TYPE (targ
)))
8488 targ
= TREE_OPERAND (targ
, 0);
8489 /* But don't strip any other reference bindings; binding a temporary to a
8490 reference prevents copy elision. */
8491 while ((CONVERT_EXPR_P (targ
)
8492 && !TYPE_REF_P (TREE_TYPE (targ
)))
8493 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8494 targ
= TREE_OPERAND (targ
, 0);
8495 if (TREE_CODE (targ
) == ADDR_EXPR
)
8497 targ
= TREE_OPERAND (targ
, 0);
8498 if (!same_type_ignoring_top_level_qualifiers_p
8499 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8508 arg
= cp_build_fold_indirect_ref (arg
);
8510 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8512 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8513 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8515 /* It's from binding the ref parm to a packed field. */
8516 || convs
[0]->need_temporary_p
8518 /* See unsafe_copy_elision_p. */
8519 || DECL_BASE_CONSTRUCTOR_P (fn
));
8522 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8523 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8525 /* [class.copy]: the copy constructor is implicitly defined even if the
8526 implementation elided its use. But don't warn about deprecation when
8527 eliding a temporary, as then no copy is actually performed. */
8528 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8530 /* The language says this isn't called. */;
8533 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8534 return error_mark_node
;
8535 already_used
= true;
8538 cp_warn_deprecated_use (fn
, complain
);
8540 /* If we're creating a temp and we already have one, don't create a
8541 new one. If we're not creating a temp but we get one, use
8542 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8543 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8544 temp or an INIT_EXPR otherwise. */
8545 if (is_dummy_object (fa
))
8547 if (TREE_CODE (arg
) == TARGET_EXPR
)
8550 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8552 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8555 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8557 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8561 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8562 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8563 && trivial_fn_p (fn
))
8565 tree to
= cp_stabilize_reference
8566 (cp_build_fold_indirect_ref (argarray
[0]));
8567 tree type
= TREE_TYPE (to
);
8568 tree as_base
= CLASSTYPE_AS_BASE (type
);
8569 tree arg
= argarray
[1];
8570 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
8572 if (is_really_empty_class (type
, /*ignore_vptr*/true))
8574 /* Avoid copying empty classes. */
8575 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8576 TREE_NO_WARNING (val
) = 1;
8578 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8580 if (is_std_init_list (type
)
8581 && conv_binds_ref_to_prvalue (convs
[1]))
8582 warning_at (loc
, OPT_Winit_list_lifetime
,
8583 "assignment from temporary initializer_list does not "
8584 "extend the lifetime of the underlying array");
8585 arg
= cp_build_fold_indirect_ref (arg
);
8586 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8590 /* We must only copy the non-tail padding parts. */
8592 tree array_type
, alias_set
;
8594 arg2
= TYPE_SIZE_UNIT (as_base
);
8595 arg0
= cp_build_addr_expr (to
, complain
);
8597 array_type
= build_array_type (unsigned_char_type_node
,
8599 (size_binop (MINUS_EXPR
,
8600 arg2
, size_int (1))));
8601 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8602 t
= build2 (MODIFY_EXPR
, void_type_node
,
8603 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8604 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8605 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8606 TREE_NO_WARNING (val
) = 1;
8609 cp_warn_deprecated_use (fn
, complain
);
8613 else if (trivial_fn_p (fn
))
8615 if (DECL_DESTRUCTOR_P (fn
))
8616 return build_trivial_dtor_call (argarray
[0]);
8617 else if (default_ctor_p (fn
))
8619 if (is_dummy_object (argarray
[0]))
8620 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8621 no_cleanup_complain
);
8623 return cp_build_fold_indirect_ref (argarray
[0]);
8627 gcc_assert (!force_elide
);
8630 && !mark_used (fn
, complain
))
8631 return error_mark_node
;
8633 /* Warn if the built-in writes to an object of a non-trivial type. */
8634 if (warn_class_memaccess
8635 && vec_safe_length (args
) >= 2
8636 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8637 maybe_warn_class_memaccess (input_location
, fn
, args
);
8639 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8642 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8644 ba_any
, NULL
, complain
);
8645 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8647 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8649 if (TREE_SIDE_EFFECTS (argarray
[0]))
8650 argarray
[0] = save_expr (argarray
[0]);
8651 t
= build_pointer_type (TREE_TYPE (fn
));
8652 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8657 fn
= build_addr_func (fn
, complain
);
8658 if (fn
== error_mark_node
)
8659 return error_mark_node
;
8662 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8663 if (call
== error_mark_node
)
8665 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8667 tree c
= extract_call_expr (call
);
8668 /* build_new_op_1 will clear this when appropriate. */
8669 CALL_EXPR_ORDERED_ARGS (c
) = true;
8673 tree c
= extract_call_expr (call
);
8674 if (TREE_CODE (c
) == CALL_EXPR
)
8675 TREE_NO_WARNING (c
) = 1;
8683 /* Return the DECL of the first non-static subobject of class TYPE
8684 that satisfies the predicate PRED or null if none can be found. */
8686 template <class Predicate
>
8688 first_non_static_field (tree type
, Predicate pred
)
8690 if (!type
|| !CLASS_TYPE_P (type
))
8693 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8695 if (TREE_CODE (field
) != FIELD_DECL
)
8697 if (TREE_STATIC (field
))
8705 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8706 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8708 tree base
= TREE_TYPE (base_binfo
);
8711 if (tree field
= first_non_static_field (base
, pred
))
8718 struct NonPublicField
8720 bool operator() (const_tree t
)
8722 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8726 /* Return the DECL of the first non-public subobject of class TYPE
8727 or null if none can be found. */
8730 first_non_public_field (tree type
)
8732 return first_non_static_field (type
, NonPublicField ());
8735 struct NonTrivialField
8737 bool operator() (const_tree t
)
8739 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8743 /* Return the DECL of the first non-trivial subobject of class TYPE
8744 or null if none can be found. */
8747 first_non_trivial_field (tree type
)
8749 return first_non_static_field (type
, NonTrivialField ());
8752 } /* unnamed namespace */
8754 /* Return true if all copy and move assignment operator overloads for
8755 class TYPE are trivial and at least one of them is not deleted and,
8756 when ACCESS is set, accessible. Return false otherwise. Set
8757 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8758 copy or move assignment. */
8761 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8763 tree fns
= get_class_binding (type
, assign_op_identifier
);
8764 bool all_trivial
= true;
8766 /* Iterate over overloads of the assignment operator, checking
8767 accessible copy assignments for triviality. */
8769 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8773 /* Skip operators that aren't copy assignments. */
8777 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8778 || accessible_p (TYPE_BINFO (type
), f
, true));
8780 /* Skip template assignment operators and deleted functions. */
8781 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8787 if (!accessible
|| !trivial_fn_p (f
))
8788 all_trivial
= false;
8790 /* Break early when both properties have been determined. */
8791 if (*hasassign
&& !all_trivial
)
8795 /* Return true if they're all trivial and one of the expressions
8796 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8797 tree ref
= cp_build_reference_type (type
, false);
8799 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8800 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8803 /* Return true if all copy and move ctor overloads for class TYPE are
8804 trivial and at least one of them is not deleted and, when ACCESS is
8805 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8806 to true when the TYPE has a (not necessarily trivial) default and copy
8807 (or move) ctor, respectively. */
8810 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8812 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8813 bool all_trivial
= true;
8815 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8819 /* Skip template constructors. */
8820 if (TREE_CODE (f
) != FUNCTION_DECL
)
8823 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8825 /* Skip ctors other than default, copy, and move. */
8826 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8829 if (DECL_DELETED_FN (f
))
8832 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8833 || accessible_p (TYPE_BINFO (type
), f
, true));
8836 hasctor
[cpy_or_move_ctor_p
] = true;
8838 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8839 all_trivial
= false;
8841 /* Break early when both properties have been determined. */
8842 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8849 /* Issue a warning on a call to the built-in function FNDECL if it is
8850 a raw memory write whose destination is not an object of (something
8851 like) trivial or standard layout type with a non-deleted assignment
8852 and copy ctor. Detects const correctness violations, corrupting
8853 references, virtual table pointers, and bypassing non-trivial
8857 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8858 const vec
<tree
, va_gc
> *args
)
8860 /* Except for bcopy where it's second, the destination pointer is
8861 the first argument for all functions handled here. Compute
8862 the index of the destination and source arguments. */
8863 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8864 unsigned srcidx
= !dstidx
;
8866 tree dest
= (*args
)[dstidx
];
8867 if (!TREE_TYPE (dest
) || !INDIRECT_TYPE_P (TREE_TYPE (dest
)))
8870 tree srctype
= NULL_TREE
;
8872 /* Determine the type of the pointed-to object and whether it's
8873 a complete class type. */
8874 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8876 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8879 /* Check to see if the raw memory call is made by a non-static member
8880 function with THIS as the destination argument for the destination
8881 type. If so, and if the class has no non-trivial bases or members,
8882 be more permissive. */
8883 if (current_function_decl
8884 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8885 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8887 tree ctx
= DECL_CONTEXT (current_function_decl
);
8888 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8889 tree binfo
= TYPE_BINFO (ctx
);
8892 && !BINFO_VTABLE (binfo
)
8893 && !first_non_trivial_field (desttype
))
8897 /* True if the class is trivial. */
8898 bool trivial
= trivial_type_p (desttype
);
8900 /* Set to true if DESTYPE has an accessible copy assignment. */
8901 bool hasassign
= false;
8902 /* True if all of the class' overloaded copy assignment operators
8903 are all trivial (and not deleted) and at least one of them is
8905 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8907 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8909 bool hasctors
[2] = { false, false };
8911 /* True if all of the class' overloaded copy constructors are all
8912 trivial (and not deleted) and at least one of them is accessible. */
8913 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8915 /* Set FLD to the first private/protected member of the class. */
8916 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8918 /* The warning format string. */
8919 const char *warnfmt
= NULL
;
8920 /* A suggested alternative to offer instead of the raw memory call.
8921 Empty string when none can be come up with. */
8922 const char *suggest
= "";
8923 bool warned
= false;
8925 switch (DECL_FUNCTION_CODE (fndecl
))
8927 case BUILT_IN_MEMSET
:
8928 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8930 /* Diagnose setting non-copy-assignable or non-trivial types,
8931 or types with a private member, to (potentially) non-zero
8932 bytes. Since the value of the bytes being written is unknown,
8933 suggest using assignment instead (if one exists). Also warn
8934 for writes into objects for which zero-initialization doesn't
8935 mean all bits clear (pointer-to-member data, where null is all
8936 bits set). Since the value being written is (most likely)
8937 non-zero, simply suggest assignment (but not copy assignment). */
8938 suggest
= "; use assignment instead";
8940 warnfmt
= G_("%qD writing to an object of type %#qT with "
8941 "no trivial copy-assignment");
8943 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8946 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8947 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8948 "%qD writing to an object of type %#qT with "
8950 fndecl
, desttype
, access
, fld
);
8952 else if (!zero_init_p (desttype
))
8953 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8954 "a pointer to data member%s");
8960 case BUILT_IN_BZERO
:
8961 /* Similarly to the above, diagnose clearing non-trivial or non-
8962 standard layout objects, or objects of types with no assignmenmt.
8963 Since the value being written is known to be zero, suggest either
8964 copy assignment, copy ctor, or default ctor as an alternative,
8965 depending on what's available. */
8967 if (hasassign
&& hasctors
[0])
8968 suggest
= G_("; use assignment or value-initialization instead");
8970 suggest
= G_("; use assignment instead");
8971 else if (hasctors
[0])
8972 suggest
= G_("; use value-initialization instead");
8975 warnfmt
= G_("%qD clearing an object of type %#qT with "
8976 "no trivial copy-assignment%s");
8978 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8979 else if (!zero_init_p (desttype
))
8980 warnfmt
= G_("%qD clearing an object of type %#qT containing "
8981 "a pointer-to-member%s");
8984 case BUILT_IN_BCOPY
:
8985 case BUILT_IN_MEMCPY
:
8986 case BUILT_IN_MEMMOVE
:
8987 case BUILT_IN_MEMPCPY
:
8988 /* Determine the type of the source object. */
8989 srctype
= TREE_TYPE ((*args
)[srcidx
]);
8990 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
8991 srctype
= void_type_node
;
8993 srctype
= TREE_TYPE (srctype
);
8995 /* Since it's impossible to determine wheter the byte copy is
8996 being used in place of assignment to an existing object or
8997 as a substitute for initialization, assume it's the former.
8998 Determine the best alternative to use instead depending on
8999 what's not deleted. */
9000 if (hasassign
&& hasctors
[1])
9001 suggest
= G_("; use copy-assignment or copy-initialization instead");
9003 suggest
= G_("; use copy-assignment instead");
9004 else if (hasctors
[1])
9005 suggest
= G_("; use copy-initialization instead");
9008 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
9009 "copy-assignment%s");
9010 else if (!trivially_copyable_p (desttype
))
9011 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
9014 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
9017 && !VOID_TYPE_P (srctype
)
9018 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9019 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9022 /* Warn when copying into a non-trivial object from an object
9023 of a different type other than void or char. */
9024 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9025 "%qD copying an object of non-trivial type "
9026 "%#qT from an array of %#qT",
9027 fndecl
, desttype
, srctype
);
9030 && !VOID_TYPE_P (srctype
)
9031 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9032 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9035 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
9036 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9037 "%qD copying an object of type %#qT with "
9038 "%qs member %qD from an array of %#qT; use "
9039 "assignment or copy-initialization instead",
9040 fndecl
, desttype
, access
, fld
, srctype
);
9042 else if (!trivial
&& vec_safe_length (args
) > 2)
9044 tree sz
= maybe_constant_value ((*args
)[2]);
9045 if (!tree_fits_uhwi_p (sz
))
9048 /* Finally, warn on partial copies. */
9049 unsigned HOST_WIDE_INT typesize
9050 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
9051 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
9052 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9053 (typesize
- partial
> 1
9054 ? G_("%qD writing to an object of "
9055 "a non-trivial type %#qT leaves %wu "
9057 : G_("%qD writing to an object of "
9058 "a non-trivial type %#qT leaves %wu "
9060 fndecl
, desttype
, typesize
- partial
);
9064 case BUILT_IN_REALLOC
:
9066 if (!trivially_copyable_p (desttype
))
9067 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
9068 "%#qT; use %<new%> and %<delete%> instead");
9070 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
9071 "constructor; use %<new%> and %<delete%> instead");
9072 else if (!get_dtor (desttype
, tf_none
))
9073 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
9077 tree sz
= maybe_constant_value ((*args
)[1]);
9078 if (TREE_CODE (sz
) == INTEGER_CST
9079 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
9080 /* Finally, warn on reallocation into insufficient space. */
9081 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9082 "%qD moving an object of non-trivial type "
9083 "%#qT and size %E into a region of size %E",
9084 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
9096 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9097 warnfmt
, fndecl
, desttype
, suggest
);
9099 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9100 warnfmt
, fndecl
, desttype
);
9104 inform (location_of (desttype
), "%#qT declared here", desttype
);
9107 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
9108 This function performs no overload resolution, conversion, or other
9109 high-level operations. */
9112 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
9113 tsubst_flags_t complain
)
9117 /* Remember roughly where this call is. */
9118 location_t loc
= cp_expr_loc_or_loc (fn
, input_location
);
9119 fn
= build_call_a (fn
, nargs
, argarray
);
9120 SET_EXPR_LOCATION (fn
, loc
);
9122 fndecl
= get_callee_fndecl (fn
);
9124 /* Check that arguments to builtin functions match the expectations. */
9126 && !processing_template_decl
9127 && fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
9131 /* We need to take care that values to BUILT_IN_NORMAL
9133 for (i
= 0; i
< nargs
; i
++)
9134 argarray
[i
] = maybe_constant_value (argarray
[i
]);
9136 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
9138 return error_mark_node
;
9141 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9144 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9145 function call is either the operand of a decltype-specifier or the
9146 right operand of a comma operator that is the operand of a
9147 decltype-specifier, a temporary object is not introduced for the
9148 prvalue. The type of the prvalue may be incomplete. */
9149 if (!(complain
& tf_decltype
))
9151 fn
= require_complete_type_sfinae (fn
, complain
);
9152 if (fn
== error_mark_node
)
9153 return error_mark_node
;
9155 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9157 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9158 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9161 return convert_from_reference (fn
);
9164 /* Returns the value to use for the in-charge parameter when making a
9165 call to a function with the indicated NAME.
9167 FIXME:Can't we find a neater way to do this mapping? */
9170 in_charge_arg_for_name (tree name
)
9172 if (IDENTIFIER_CTOR_P (name
))
9174 if (name
== complete_ctor_identifier
)
9175 return integer_one_node
;
9176 gcc_checking_assert (name
== base_ctor_identifier
);
9180 if (name
== complete_dtor_identifier
)
9181 return integer_two_node
;
9182 else if (name
== deleting_dtor_identifier
)
9183 return integer_three_node
;
9184 gcc_checking_assert (name
== base_dtor_identifier
);
9187 return integer_zero_node
;
9190 /* We've built up a constructor call RET. Complain if it delegates to the
9191 constructor we're currently compiling. */
9194 check_self_delegation (tree ret
)
9196 if (TREE_CODE (ret
) == TARGET_EXPR
)
9197 ret
= TARGET_EXPR_INITIAL (ret
);
9198 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9199 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9200 error ("constructor delegates to itself");
9203 /* Build a call to a constructor, destructor, or an assignment
9204 operator for INSTANCE, an expression with class type. NAME
9205 indicates the special member function to call; *ARGS are the
9206 arguments. ARGS may be NULL. This may change ARGS. BINFO
9207 indicates the base of INSTANCE that is to be passed as the `this'
9208 parameter to the member function called.
9210 FLAGS are the LOOKUP_* flags to use when processing the call.
9212 If NAME indicates a complete object constructor, INSTANCE may be
9213 NULL_TREE. In this case, the caller will call build_cplus_new to
9214 store the newly constructed object into a VAR_DECL. */
9217 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9218 tree binfo
, int flags
, tsubst_flags_t complain
)
9221 /* The type of the subobject to be constructed or destroyed. */
9223 vec
<tree
, va_gc
> *allocated
= NULL
;
9226 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9228 if (error_operand_p (instance
))
9229 return error_mark_node
;
9231 if (IDENTIFIER_DTOR_P (name
))
9233 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9234 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9235 /* Shortcut to avoid lazy destructor declaration. */
9236 return build_trivial_dtor_call (instance
);
9241 /* Resolve the name. */
9242 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9243 return error_mark_node
;
9245 binfo
= TYPE_BINFO (binfo
);
9248 gcc_assert (binfo
!= NULL_TREE
);
9250 class_type
= BINFO_TYPE (binfo
);
9252 /* Handle the special case where INSTANCE is NULL_TREE. */
9253 if (name
== complete_ctor_identifier
&& !instance
)
9254 instance
= build_dummy_object (class_type
);
9257 /* Convert to the base class, if necessary. */
9258 if (!same_type_ignoring_top_level_qualifiers_p
9259 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9261 if (IDENTIFIER_CDTOR_P (name
))
9262 /* For constructors and destructors, either the base is
9263 non-virtual, or it is virtual but we are doing the
9264 conversion from a constructor or destructor for the
9265 complete object. In either case, we can convert
9267 instance
= convert_to_base_statically (instance
, binfo
);
9270 /* However, for assignment operators, we must convert
9271 dynamically if the base is virtual. */
9272 gcc_checking_assert (name
== assign_op_identifier
);
9273 instance
= build_base_path (PLUS_EXPR
, instance
,
9274 binfo
, /*nonnull=*/1, complain
);
9279 gcc_assert (instance
!= NULL_TREE
);
9281 /* In C++17, "If the initializer expression is a prvalue and the
9282 cv-unqualified version of the source type is the same class as the class
9283 of the destination, the initializer expression is used to initialize the
9284 destination object." Handle that here to avoid doing overload
9286 if (cxx_dialect
>= cxx17
9287 && args
&& vec_safe_length (*args
) == 1
9288 && name
== complete_ctor_identifier
)
9290 tree arg
= (**args
)[0];
9292 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9293 && !TYPE_HAS_LIST_CTOR (class_type
)
9294 && CONSTRUCTOR_NELTS (arg
) == 1)
9295 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9297 if ((TREE_CODE (arg
) == TARGET_EXPR
9298 || TREE_CODE (arg
) == CONSTRUCTOR
)
9299 && (same_type_ignoring_top_level_qualifiers_p
9300 (class_type
, TREE_TYPE (arg
))))
9302 if (is_dummy_object (instance
))
9304 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9305 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9307 if ((complain
& tf_error
)
9308 && (flags
& LOOKUP_DELEGATING_CONS
))
9309 check_self_delegation (arg
);
9310 /* Avoid change of behavior on Wunused-var-2.C. */
9311 instance
= mark_lvalue_use (instance
);
9312 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9316 fns
= lookup_fnfields (binfo
, name
, 1);
9318 /* When making a call to a constructor or destructor for a subobject
9319 that uses virtual base classes, pass down a pointer to a VTT for
9321 if ((name
== base_ctor_identifier
9322 || name
== base_dtor_identifier
)
9323 && CLASSTYPE_VBASECLASSES (class_type
))
9328 /* If the current function is a complete object constructor
9329 or destructor, then we fetch the VTT directly.
9330 Otherwise, we look it up using the VTT we were given. */
9331 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9332 vtt
= decay_conversion (vtt
, complain
);
9333 if (vtt
== error_mark_node
)
9334 return error_mark_node
;
9335 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9336 if (BINFO_SUBVTT_INDEX (binfo
))
9337 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9343 allocated
= make_tree_vector ();
9347 vec_safe_insert (*args
, 0, sub_vtt
);
9350 ret
= build_new_method_call (instance
, fns
, args
,
9351 TYPE_BINFO (BINFO_TYPE (binfo
)),
9355 if (allocated
!= NULL
)
9356 release_tree_vector (allocated
);
9358 if ((complain
& tf_error
)
9359 && (flags
& LOOKUP_DELEGATING_CONS
)
9360 && name
== complete_ctor_identifier
)
9361 check_self_delegation (ret
);
9366 /* Return the NAME, as a C string. The NAME indicates a function that
9367 is a member of TYPE. *FREE_P is set to true if the caller must
9368 free the memory returned.
9370 Rather than go through all of this, we should simply set the names
9371 of constructors and destructors appropriately, and dispense with
9372 ctor_identifier, dtor_identifier, etc. */
9375 name_as_c_string (tree name
, tree type
, bool *free_p
)
9377 const char *pretty_name
;
9379 /* Assume that we will not allocate memory. */
9381 /* Constructors and destructors are special. */
9382 if (IDENTIFIER_CDTOR_P (name
))
9385 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9386 /* For a destructor, add the '~'. */
9387 if (IDENTIFIER_DTOR_P (name
))
9389 pretty_name
= concat ("~", pretty_name
, NULL
);
9390 /* Remember that we need to free the memory allocated. */
9394 else if (IDENTIFIER_CONV_OP_P (name
))
9396 pretty_name
= concat ("operator ",
9397 type_as_string_translate (TREE_TYPE (name
),
9398 TFF_PLAIN_IDENTIFIER
),
9400 /* Remember that we need to free the memory allocated. */
9404 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9406 return CONST_CAST (char *, pretty_name
);
9409 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9412 static z_candidate
*
9413 single_z_candidate (z_candidate
*candidates
)
9415 if (candidates
== NULL
)
9418 if (candidates
->next
)
9424 /* If CANDIDATE is invalid due to a bad argument type, return the
9425 pertinent conversion_info.
9427 Otherwise, return NULL. */
9429 static const conversion_info
*
9430 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9432 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9433 rejection_reason
*r
= candidate
->reason
;
9443 case rr_arg_conversion
:
9444 return &r
->u
.conversion
;
9446 case rr_bad_arg_conversion
:
9447 return &r
->u
.bad_conversion
;
9451 /* Issue an error and note complaining about a bad argument type at a
9452 callsite with a single candidate FNDECL.
9454 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9455 case input_location is used).
9456 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9457 the formal parameter. */
9460 complain_about_bad_argument (location_t arg_loc
,
9461 tree from_type
, tree to_type
,
9462 tree fndecl
, int parmnum
)
9464 auto_diagnostic_group d
;
9465 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9466 range_label
*label
= &rhs_label
;
9467 if (arg_loc
== UNKNOWN_LOCATION
)
9469 arg_loc
= input_location
;
9472 gcc_rich_location
richloc (arg_loc
, label
);
9474 "cannot convert %qH to %qI",
9475 from_type
, to_type
);
9476 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9480 /* Subroutine of build_new_method_call_1, for where there are no viable
9481 candidates for the call. */
9484 complain_about_no_candidates_for_method_call (tree instance
,
9485 z_candidate
*candidates
,
9486 tree explicit_targs
,
9488 tree optype
, tree name
,
9489 bool skip_first_for_error
,
9490 vec
<tree
, va_gc
> *user_args
)
9492 auto_diagnostic_group d
;
9493 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9494 cxx_incomplete_type_error (instance
, basetype
);
9496 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9497 basetype
, optype
, build_tree_list_vec (user_args
),
9498 TREE_TYPE (instance
));
9501 /* Special-case for when there's a single candidate that's failing
9502 due to a bad argument type. */
9503 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9504 if (const conversion_info
*conv
9505 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9507 complain_about_bad_argument (conv
->loc
,
9508 conv
->from
, conv
->to_type
,
9509 candidate
->fn
, conv
->n_arg
);
9513 tree arglist
= build_tree_list_vec (user_args
);
9514 tree errname
= name
;
9515 bool twiddle
= false;
9516 if (IDENTIFIER_CDTOR_P (errname
))
9518 twiddle
= IDENTIFIER_DTOR_P (errname
);
9519 errname
= constructor_name (basetype
);
9522 errname
= lookup_template_function (errname
, explicit_targs
);
9523 if (skip_first_for_error
)
9524 arglist
= TREE_CHAIN (arglist
);
9525 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9526 basetype
, &"~"[!twiddle
], errname
, arglist
,
9527 TREE_TYPE (instance
));
9529 print_z_candidates (location_of (name
), candidates
);
9532 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9533 be set, upon return, to the function called. ARGS may be NULL.
9534 This may change ARGS. */
9537 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9538 tree conversion_path
, int flags
,
9539 tree
*fn_p
, tsubst_flags_t complain
)
9541 struct z_candidate
*candidates
= 0, *cand
;
9542 tree explicit_targs
= NULL_TREE
;
9543 tree basetype
= NULL_TREE
;
9544 tree access_binfo
, binfo
;
9546 tree first_mem_arg
= NULL_TREE
;
9548 bool skip_first_for_error
;
9549 vec
<tree
, va_gc
> *user_args
;
9552 int template_only
= 0;
9556 vec
<tree
, va_gc
> *orig_args
= NULL
;
9559 gcc_assert (instance
!= NULL_TREE
);
9561 /* We don't know what function we're going to call, yet. */
9565 if (error_operand_p (instance
)
9566 || !fns
|| error_operand_p (fns
))
9567 return error_mark_node
;
9569 if (!BASELINK_P (fns
))
9571 if (complain
& tf_error
)
9572 error ("call to non-function %qD", fns
);
9573 return error_mark_node
;
9576 orig_instance
= instance
;
9579 /* Dismantle the baselink to collect all the information we need. */
9580 if (!conversion_path
)
9581 conversion_path
= BASELINK_BINFO (fns
);
9582 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9583 binfo
= BASELINK_BINFO (fns
);
9584 optype
= BASELINK_OPTYPE (fns
);
9585 fns
= BASELINK_FUNCTIONS (fns
);
9586 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9588 explicit_targs
= TREE_OPERAND (fns
, 1);
9589 fns
= TREE_OPERAND (fns
, 0);
9592 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
9593 || TREE_CODE (fns
) == TEMPLATE_DECL
9594 || TREE_CODE (fns
) == OVERLOAD
);
9595 fn
= OVL_FIRST (fns
);
9596 name
= DECL_NAME (fn
);
9598 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9599 gcc_assert (CLASS_TYPE_P (basetype
));
9601 user_args
= args
== NULL
? NULL
: *args
;
9602 /* Under DR 147 A::A() is an invalid constructor call,
9603 not a functional cast. */
9604 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9606 if (! (complain
& tf_error
))
9607 return error_mark_node
;
9609 basetype
= DECL_CONTEXT (fn
);
9610 name
= constructor_name (basetype
);
9611 auto_diagnostic_group d
;
9612 if (permerror (input_location
,
9613 "cannot call constructor %<%T::%D%> directly",
9615 inform (input_location
, "for a function-style cast, remove the "
9616 "redundant %<::%D%>", name
);
9617 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9622 if (processing_template_decl
)
9624 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9625 instance
= build_non_dependent_expr (instance
);
9627 make_args_non_dependent (*args
);
9630 /* Process the argument list. */
9631 if (args
!= NULL
&& *args
!= NULL
)
9633 *args
= resolve_args (*args
, complain
);
9635 return error_mark_node
;
9639 /* Consider the object argument to be used even if we end up selecting a
9640 static member function. */
9641 instance
= mark_type_use (instance
);
9643 /* Figure out whether to skip the first argument for the error
9644 message we will display to users if an error occurs. We don't
9645 want to display any compiler-generated arguments. The "this"
9646 pointer hasn't been added yet. However, we must remove the VTT
9647 pointer if this is a call to a base-class constructor or
9649 skip_first_for_error
= false;
9650 if (IDENTIFIER_CDTOR_P (name
))
9652 /* Callers should explicitly indicate whether they want to ctor
9653 the complete object or just the part without virtual bases. */
9654 gcc_assert (name
!= ctor_identifier
);
9656 /* Remove the VTT pointer, if present. */
9657 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9658 && CLASSTYPE_VBASECLASSES (basetype
))
9659 skip_first_for_error
= true;
9661 /* It's OK to call destructors and constructors on cv-qualified
9662 objects. Therefore, convert the INSTANCE to the unqualified
9663 type, if necessary. */
9664 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9666 instance
= build_this (instance
);
9667 instance
= build_nop (build_pointer_type (basetype
), instance
);
9668 instance
= build_fold_indirect_ref (instance
);
9672 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9674 /* For the overload resolution we need to find the actual `this`
9675 that would be captured if the call turns out to be to a
9676 non-static member function. Do not actually capture it at this
9678 if (DECL_CONSTRUCTOR_P (fn
))
9679 /* Constructors don't use the enclosing 'this'. */
9680 first_mem_arg
= instance
;
9682 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9684 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9685 p
= conversion_obstack_alloc (0);
9687 /* The number of arguments artificial parms in ARGS; we subtract one because
9688 there's no 'this' in ARGS. */
9689 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9691 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9692 initializer, not T({ }). */
9693 if (DECL_CONSTRUCTOR_P (fn
)
9694 && vec_safe_length (user_args
) > skip
9695 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9697 tree init_list
= (*user_args
)[skip
];
9698 tree init
= NULL_TREE
;
9700 gcc_assert (user_args
->length () == skip
+ 1
9701 && !(flags
& LOOKUP_ONLYCONVERTING
));
9703 /* If the initializer list has no elements and T is a class type with
9704 a default constructor, the object is value-initialized. Handle
9705 this here so we don't need to handle it wherever we use
9706 build_special_member_call. */
9707 if (CONSTRUCTOR_NELTS (init_list
) == 0
9708 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9709 /* For a user-provided default constructor, use the normal
9710 mechanisms so that protected access works. */
9711 && type_has_non_user_provided_default_constructor (basetype
)
9712 && !processing_template_decl
)
9713 init
= build_value_init (basetype
, complain
);
9715 /* If BASETYPE is an aggregate, we need to do aggregate
9717 else if (CP_AGGREGATE_TYPE_P (basetype
))
9719 init
= reshape_init (basetype
, init_list
, complain
);
9720 init
= digest_init (basetype
, init
, complain
);
9725 if (is_dummy_object (instance
))
9726 return get_target_expr_sfinae (init
, complain
);
9727 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9728 TREE_SIDE_EFFECTS (init
) = true;
9732 /* Otherwise go ahead with overload resolution. */
9733 add_list_candidates (fns
, first_mem_arg
, user_args
,
9734 basetype
, explicit_targs
, template_only
,
9735 conversion_path
, access_binfo
, flags
,
9736 &candidates
, complain
);
9739 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9740 explicit_targs
, template_only
, conversion_path
,
9741 access_binfo
, flags
, &candidates
, complain
);
9743 any_viable_p
= false;
9744 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9748 if (complain
& tf_error
)
9749 complain_about_no_candidates_for_method_call (instance
, candidates
,
9750 explicit_targs
, basetype
,
9752 skip_first_for_error
,
9754 call
= error_mark_node
;
9758 cand
= tourney (candidates
, complain
);
9765 if (complain
& tf_error
)
9767 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9768 arglist
= build_tree_list_vec (user_args
);
9769 if (skip_first_for_error
)
9770 arglist
= TREE_CHAIN (arglist
);
9771 auto_diagnostic_group d
;
9772 if (!any_strictly_viable (candidates
))
9773 error ("no matching function for call to %<%s(%A)%>",
9774 pretty_name
, arglist
);
9776 error ("call of overloaded %<%s(%A)%> is ambiguous",
9777 pretty_name
, arglist
);
9778 print_z_candidates (location_of (name
), candidates
);
9782 call
= error_mark_node
;
9789 if (!(flags
& LOOKUP_NONVIRTUAL
)
9790 && DECL_PURE_VIRTUAL_P (fn
)
9791 && instance
== current_class_ref
9792 && (complain
& tf_warning
))
9794 /* This is not an error, it is runtime undefined
9796 if (!current_function_decl
)
9797 warning (0, "pure virtual %q#D called from "
9798 "non-static data member initializer", fn
);
9799 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9800 || DECL_DESTRUCTOR_P (current_function_decl
))
9801 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9802 ? G_("pure virtual %q#D called from constructor")
9803 : G_("pure virtual %q#D called from destructor")),
9807 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9808 && !DECL_CONSTRUCTOR_P (fn
)
9809 && is_dummy_object (instance
))
9811 instance
= maybe_resolve_dummy (instance
, true);
9812 if (instance
== error_mark_node
)
9813 call
= error_mark_node
;
9814 else if (!is_dummy_object (instance
))
9816 /* We captured 'this' in the current lambda now that
9817 we know we really need it. */
9818 cand
->first_arg
= instance
;
9820 else if (any_dependent_bases_p ())
9821 /* We can't tell until instantiation time whether we can use
9822 *this as the implicit object argument. */;
9825 if (complain
& tf_error
)
9826 error ("cannot call member function %qD without object",
9828 call
= error_mark_node
;
9832 if (call
!= error_mark_node
)
9834 /* Optimize away vtable lookup if we know that this
9835 function can't be overridden. We need to check if
9836 the context and the type where we found fn are the same,
9837 actually FN might be defined in a different class
9838 type because of a using-declaration. In this case, we
9839 do not want to perform a non-virtual call. */
9840 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9841 && same_type_ignoring_top_level_qualifiers_p
9842 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9843 && resolves_to_fixed_type_p (instance
, 0))
9844 flags
|= LOOKUP_NONVIRTUAL
;
9846 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9847 /* Now we know what function is being called. */
9850 /* Build the actual CALL_EXPR. */
9851 call
= build_over_call (cand
, flags
, complain
);
9852 /* In an expression of the form `a->f()' where `f' turns
9853 out to be a static member function, `a' is
9854 none-the-less evaluated. */
9855 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9856 && !is_dummy_object (instance
)
9857 && TREE_SIDE_EFFECTS (instance
))
9859 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9862 if (TREE_THIS_VOLATILE (a
))
9864 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9866 else if (call
!= error_mark_node
9867 && DECL_DESTRUCTOR_P (cand
->fn
)
9868 && !VOID_TYPE_P (TREE_TYPE (call
)))
9869 /* An explicit call of the form "x->~X()" has type
9870 "void". However, on platforms where destructors
9871 return "this" (i.e., those where
9872 targetm.cxx.cdtor_returns_this is true), such calls
9873 will appear to have a return value of pointer type
9874 to the low-level call machinery. We do not want to
9875 change the low-level machinery, since we want to be
9876 able to optimize "delete f()" on such platforms as
9877 "operator delete(~X(f()))" (rather than generating
9878 "t = f(), ~X(t), operator delete (t)"). */
9879 call
= build_nop (void_type_node
, call
);
9884 if (processing_template_decl
&& call
!= error_mark_node
)
9886 bool cast_to_void
= false;
9888 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9889 call
= TREE_OPERAND (call
, 1);
9890 else if (TREE_CODE (call
) == NOP_EXPR
)
9892 cast_to_void
= true;
9893 call
= TREE_OPERAND (call
, 0);
9895 if (INDIRECT_REF_P (call
))
9896 call
= TREE_OPERAND (call
, 0);
9897 call
= (build_min_non_dep_call_vec
9899 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9900 orig_instance
, orig_fns
, NULL_TREE
),
9902 SET_EXPR_LOCATION (call
, input_location
);
9903 call
= convert_from_reference (call
);
9905 call
= build_nop (void_type_node
, call
);
9908 /* Free all the conversions we allocated. */
9909 obstack_free (&conversion_obstack
, p
);
9911 if (orig_args
!= NULL
)
9912 release_tree_vector (orig_args
);
9917 /* Wrapper for above. */
9920 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9921 tree conversion_path
, int flags
,
9922 tree
*fn_p
, tsubst_flags_t complain
)
9925 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9926 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9928 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9932 /* Returns true iff standard conversion sequence ICS1 is a proper
9933 subsequence of ICS2. */
9936 is_subseq (conversion
*ics1
, conversion
*ics2
)
9938 /* We can assume that a conversion of the same code
9939 between the same types indicates a subsequence since we only get
9940 here if the types we are converting from are the same. */
9942 while (ics1
->kind
== ck_rvalue
9943 || ics1
->kind
== ck_lvalue
)
9944 ics1
= next_conversion (ics1
);
9948 while (ics2
->kind
== ck_rvalue
9949 || ics2
->kind
== ck_lvalue
)
9950 ics2
= next_conversion (ics2
);
9952 if (ics2
->kind
== ck_user
9953 || ics2
->kind
== ck_ambig
9954 || ics2
->kind
== ck_aggr
9955 || ics2
->kind
== ck_list
9956 || ics2
->kind
== ck_identity
)
9957 /* At this point, ICS1 cannot be a proper subsequence of
9958 ICS2. We can get a USER_CONV when we are comparing the
9959 second standard conversion sequence of two user conversion
9963 ics2
= next_conversion (ics2
);
9965 while (ics2
->kind
== ck_rvalue
9966 || ics2
->kind
== ck_lvalue
)
9967 ics2
= next_conversion (ics2
);
9969 if (ics2
->kind
== ics1
->kind
9970 && same_type_p (ics2
->type
, ics1
->type
)
9971 && (ics1
->kind
== ck_identity
9972 || same_type_p (next_conversion (ics2
)->type
,
9973 next_conversion (ics1
)->type
)))
9978 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9979 be any _TYPE nodes. */
9982 is_properly_derived_from (tree derived
, tree base
)
9984 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
9987 /* We only allow proper derivation here. The DERIVED_FROM_P macro
9988 considers every class derived from itself. */
9989 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
9990 && DERIVED_FROM_P (base
, derived
));
9993 /* We build the ICS for an implicit object parameter as a pointer
9994 conversion sequence. However, such a sequence should be compared
9995 as if it were a reference conversion sequence. If ICS is the
9996 implicit conversion sequence for an implicit object parameter,
9997 modify it accordingly. */
10000 maybe_handle_implicit_object (conversion
**ics
)
10002 if ((*ics
)->this_p
)
10004 /* [over.match.funcs]
10006 For non-static member functions, the type of the
10007 implicit object parameter is "reference to cv X"
10008 where X is the class of which the function is a
10009 member and cv is the cv-qualification on the member
10010 function declaration. */
10011 conversion
*t
= *ics
;
10012 tree reference_type
;
10014 /* The `this' parameter is a pointer to a class type. Make the
10015 implicit conversion talk about a reference to that same class
10017 reference_type
= TREE_TYPE (t
->type
);
10018 reference_type
= build_reference_type (reference_type
);
10020 if (t
->kind
== ck_qual
)
10021 t
= next_conversion (t
);
10022 if (t
->kind
== ck_ptr
)
10023 t
= next_conversion (t
);
10024 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
10025 t
= direct_reference_binding (reference_type
, t
);
10027 t
->rvaluedness_matches_p
= 0;
10032 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
10033 and return the initial reference binding conversion. Otherwise,
10034 leave *ICS unchanged and return NULL. */
10036 static conversion
*
10037 maybe_handle_ref_bind (conversion
**ics
)
10039 if ((*ics
)->kind
== ck_ref_bind
)
10041 conversion
*old_ics
= *ics
;
10042 *ics
= next_conversion (old_ics
);
10043 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
10050 /* Compare two implicit conversion sequences according to the rules set out in
10051 [over.ics.rank]. Return values:
10053 1: ics1 is better than ics2
10054 -1: ics2 is better than ics1
10055 0: ics1 and ics2 are indistinguishable */
10058 compare_ics (conversion
*ics1
, conversion
*ics2
)
10064 tree deref_from_type1
= NULL_TREE
;
10065 tree deref_from_type2
= NULL_TREE
;
10066 tree deref_to_type1
= NULL_TREE
;
10067 tree deref_to_type2
= NULL_TREE
;
10068 conversion_rank rank1
, rank2
;
10070 /* REF_BINDING is nonzero if the result of the conversion sequence
10071 is a reference type. In that case REF_CONV is the reference
10072 binding conversion. */
10073 conversion
*ref_conv1
;
10074 conversion
*ref_conv2
;
10076 /* Compare badness before stripping the reference conversion. */
10077 if (ics1
->bad_p
> ics2
->bad_p
)
10079 else if (ics1
->bad_p
< ics2
->bad_p
)
10082 /* Handle implicit object parameters. */
10083 maybe_handle_implicit_object (&ics1
);
10084 maybe_handle_implicit_object (&ics2
);
10086 /* Handle reference parameters. */
10087 ref_conv1
= maybe_handle_ref_bind (&ics1
);
10088 ref_conv2
= maybe_handle_ref_bind (&ics2
);
10090 /* List-initialization sequence L1 is a better conversion sequence than
10091 list-initialization sequence L2 if L1 converts to
10092 std::initializer_list<X> for some X and L2 does not. */
10093 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
10095 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
10100 When comparing the basic forms of implicit conversion sequences (as
10101 defined in _over.best.ics_)
10103 --a standard conversion sequence (_over.ics.scs_) is a better
10104 conversion sequence than a user-defined conversion sequence
10105 or an ellipsis conversion sequence, and
10107 --a user-defined conversion sequence (_over.ics.user_) is a
10108 better conversion sequence than an ellipsis conversion sequence
10109 (_over.ics.ellipsis_). */
10110 /* Use BAD_CONVERSION_RANK because we already checked for a badness
10111 mismatch. If both ICS are bad, we try to make a decision based on
10112 what would have happened if they'd been good. This is not an
10113 extension, we'll still give an error when we build up the call; this
10114 just helps us give a more helpful error message. */
10115 rank1
= BAD_CONVERSION_RANK (ics1
);
10116 rank2
= BAD_CONVERSION_RANK (ics2
);
10120 else if (rank1
< rank2
)
10123 if (ics1
->ellipsis_p
)
10124 /* Both conversions are ellipsis conversions. */
10127 /* User-defined conversion sequence U1 is a better conversion sequence
10128 than another user-defined conversion sequence U2 if they contain the
10129 same user-defined conversion operator or constructor and if the sec-
10130 ond standard conversion sequence of U1 is better than the second
10131 standard conversion sequence of U2. */
10133 /* Handle list-conversion with the same code even though it isn't always
10134 ranked as a user-defined conversion and it doesn't have a second
10135 standard conversion sequence; it will still have the desired effect.
10136 Specifically, we need to do the reference binding comparison at the
10137 end of this function. */
10139 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
10140 || ics1
->kind
== ck_aggr
|| ics2
->kind
== ck_aggr
)
10145 for (t1
= ics1
; t1
&& t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
10146 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
10147 || t1
->kind
== ck_list
)
10149 for (t2
= ics2
; t2
&& t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
10150 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
10151 || t2
->kind
== ck_list
)
10154 if (!t1
|| !t2
|| t1
->kind
!= t2
->kind
)
10156 else if (t1
->kind
== ck_user
)
10158 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10159 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10165 /* For ambiguous or aggregate conversions, use the target type as
10166 a proxy for the conversion function. */
10167 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10171 /* We can just fall through here, after setting up
10172 FROM_TYPE1 and FROM_TYPE2. */
10173 from_type1
= t1
->type
;
10174 from_type2
= t2
->type
;
10181 /* We're dealing with two standard conversion sequences.
10185 Standard conversion sequence S1 is a better conversion
10186 sequence than standard conversion sequence S2 if
10188 --S1 is a proper subsequence of S2 (comparing the conversion
10189 sequences in the canonical form defined by _over.ics.scs_,
10190 excluding any Lvalue Transformation; the identity
10191 conversion sequence is considered to be a subsequence of
10192 any non-identity conversion sequence */
10195 while (t1
->kind
!= ck_identity
)
10196 t1
= next_conversion (t1
);
10197 from_type1
= t1
->type
;
10200 while (t2
->kind
!= ck_identity
)
10201 t2
= next_conversion (t2
);
10202 from_type2
= t2
->type
;
10205 /* One sequence can only be a subsequence of the other if they start with
10206 the same type. They can start with different types when comparing the
10207 second standard conversion sequence in two user-defined conversion
10209 if (same_type_p (from_type1
, from_type2
))
10211 if (is_subseq (ics1
, ics2
))
10213 if (is_subseq (ics2
, ics1
))
10221 --the rank of S1 is better than the rank of S2 (by the rules
10224 Standard conversion sequences are ordered by their ranks: an Exact
10225 Match is a better conversion than a Promotion, which is a better
10226 conversion than a Conversion.
10228 Two conversion sequences with the same rank are indistinguishable
10229 unless one of the following rules applies:
10231 --A conversion that does not a convert a pointer, pointer to member,
10232 or std::nullptr_t to bool is better than one that does.
10234 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10235 so that we do not have to check it explicitly. */
10236 if (ics1
->rank
< ics2
->rank
)
10238 else if (ics2
->rank
< ics1
->rank
)
10241 to_type1
= ics1
->type
;
10242 to_type2
= ics2
->type
;
10244 /* A conversion from scalar arithmetic type to complex is worse than a
10245 conversion between scalar arithmetic types. */
10246 if (same_type_p (from_type1
, from_type2
)
10247 && ARITHMETIC_TYPE_P (from_type1
)
10248 && ARITHMETIC_TYPE_P (to_type1
)
10249 && ARITHMETIC_TYPE_P (to_type2
)
10250 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10251 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10253 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10259 if (TYPE_PTR_P (from_type1
)
10260 && TYPE_PTR_P (from_type2
)
10261 && TYPE_PTR_P (to_type1
)
10262 && TYPE_PTR_P (to_type2
))
10264 deref_from_type1
= TREE_TYPE (from_type1
);
10265 deref_from_type2
= TREE_TYPE (from_type2
);
10266 deref_to_type1
= TREE_TYPE (to_type1
);
10267 deref_to_type2
= TREE_TYPE (to_type2
);
10269 /* The rules for pointers to members A::* are just like the rules
10270 for pointers A*, except opposite: if B is derived from A then
10271 A::* converts to B::*, not vice versa. For that reason, we
10272 switch the from_ and to_ variables here. */
10273 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10274 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10275 || (TYPE_PTRMEMFUNC_P (from_type1
)
10276 && TYPE_PTRMEMFUNC_P (from_type2
)
10277 && TYPE_PTRMEMFUNC_P (to_type1
)
10278 && TYPE_PTRMEMFUNC_P (to_type2
)))
10280 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10281 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10282 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10283 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10286 if (deref_from_type1
!= NULL_TREE
10287 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10288 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10290 /* This was one of the pointer or pointer-like conversions.
10294 --If class B is derived directly or indirectly from class A,
10295 conversion of B* to A* is better than conversion of B* to
10296 void*, and conversion of A* to void* is better than
10297 conversion of B* to void*. */
10298 if (VOID_TYPE_P (deref_to_type1
)
10299 && VOID_TYPE_P (deref_to_type2
))
10301 if (is_properly_derived_from (deref_from_type1
,
10304 else if (is_properly_derived_from (deref_from_type2
,
10308 else if (VOID_TYPE_P (deref_to_type1
)
10309 || VOID_TYPE_P (deref_to_type2
))
10311 if (same_type_p (deref_from_type1
, deref_from_type2
))
10313 if (VOID_TYPE_P (deref_to_type2
))
10315 if (is_properly_derived_from (deref_from_type1
,
10319 /* We know that DEREF_TO_TYPE1 is `void' here. */
10320 else if (is_properly_derived_from (deref_from_type1
,
10325 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10326 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10330 --If class B is derived directly or indirectly from class A
10331 and class C is derived directly or indirectly from B,
10333 --conversion of C* to B* is better than conversion of C* to
10336 --conversion of B* to A* is better than conversion of C* to
10338 if (same_type_p (deref_from_type1
, deref_from_type2
))
10340 if (is_properly_derived_from (deref_to_type1
,
10343 else if (is_properly_derived_from (deref_to_type2
,
10347 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10349 if (is_properly_derived_from (deref_from_type2
,
10352 else if (is_properly_derived_from (deref_from_type1
,
10358 else if (CLASS_TYPE_P (non_reference (from_type1
))
10359 && same_type_p (from_type1
, from_type2
))
10361 tree from
= non_reference (from_type1
);
10365 --binding of an expression of type C to a reference of type
10366 B& is better than binding an expression of type C to a
10367 reference of type A&
10369 --conversion of C to B is better than conversion of C to A, */
10370 if (is_properly_derived_from (from
, to_type1
)
10371 && is_properly_derived_from (from
, to_type2
))
10373 if (is_properly_derived_from (to_type1
, to_type2
))
10375 else if (is_properly_derived_from (to_type2
, to_type1
))
10379 else if (CLASS_TYPE_P (non_reference (to_type1
))
10380 && same_type_p (to_type1
, to_type2
))
10382 tree to
= non_reference (to_type1
);
10386 --binding of an expression of type B to a reference of type
10387 A& is better than binding an expression of type C to a
10388 reference of type A&,
10390 --conversion of B to A is better than conversion of C to A */
10391 if (is_properly_derived_from (from_type1
, to
)
10392 && is_properly_derived_from (from_type2
, to
))
10394 if (is_properly_derived_from (from_type2
, from_type1
))
10396 else if (is_properly_derived_from (from_type1
, from_type2
))
10403 --S1 and S2 differ only in their qualification conversion and yield
10404 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10405 qualification signature of type T1 is a proper subset of the cv-
10406 qualification signature of type T2 */
10407 if (ics1
->kind
== ck_qual
10408 && ics2
->kind
== ck_qual
10409 && same_type_p (from_type1
, from_type2
))
10411 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10418 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10419 to an implicit object parameter of a non-static member function
10420 declared without a ref-qualifier, and either S1 binds an lvalue
10421 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10422 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10423 draft standard, 13.3.3.2)
10425 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10426 types to which the references refer are the same type except for
10427 top-level cv-qualifiers, and the type to which the reference
10428 initialized by S2 refers is more cv-qualified than the type to
10429 which the reference initialized by S1 refers.
10431 DR 1328 [over.match.best]: the context is an initialization by
10432 conversion function for direct reference binding (13.3.1.6) of a
10433 reference to function type, the return type of F1 is the same kind of
10434 reference (i.e. lvalue or rvalue) as the reference being initialized,
10435 and the return type of F2 is not. */
10437 if (ref_conv1
&& ref_conv2
)
10439 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10440 && (ref_conv1
->rvaluedness_matches_p
10441 != ref_conv2
->rvaluedness_matches_p
)
10442 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10443 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10444 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10446 if (ref_conv1
->bad_p
10447 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10448 TREE_TYPE (ref_conv2
->type
)))
10449 /* Don't prefer a bad conversion that drops cv-quals to a bad
10450 conversion with the wrong rvalueness. */
10452 return (ref_conv1
->rvaluedness_matches_p
10453 - ref_conv2
->rvaluedness_matches_p
);
10456 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10458 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10459 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10460 if (ref_conv1
->bad_p
)
10462 /* Prefer the one that drops fewer cv-quals. */
10463 tree ftype
= next_conversion (ref_conv1
)->type
;
10464 int fquals
= cp_type_quals (ftype
);
10468 return comp_cv_qualification (q2
, q1
);
10472 /* Neither conversion sequence is better than the other. */
10476 /* The source type for this standard conversion sequence. */
10479 source_type (conversion
*t
)
10481 for (;; t
= next_conversion (t
))
10483 if (t
->kind
== ck_user
10484 || t
->kind
== ck_ambig
10485 || t
->kind
== ck_identity
)
10488 gcc_unreachable ();
10491 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10492 a pointer to LOSER and re-running joust to produce the warning if WINNER
10493 is actually used. */
10496 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10498 candidate_warning
*cw
= (candidate_warning
*)
10499 conversion_obstack_alloc (sizeof (candidate_warning
));
10501 cw
->next
= winner
->warnings
;
10502 winner
->warnings
= cw
;
10505 /* CAND is a constructor candidate in joust in C++17 and up. If it copies a
10506 prvalue returned from a conversion function, replace CAND with the candidate
10507 for the conversion and return true. Otherwise, return false. */
10510 joust_maybe_elide_copy (z_candidate
*&cand
)
10512 tree fn
= cand
->fn
;
10513 if (!DECL_COPY_CONSTRUCTOR_P (fn
) && !DECL_MOVE_CONSTRUCTOR_P (fn
))
10515 conversion
*conv
= cand
->convs
[0];
10516 gcc_checking_assert (conv
->kind
== ck_ref_bind
);
10517 conv
= next_conversion (conv
);
10518 if (conv
->kind
== ck_user
&& !TYPE_REF_P (conv
->type
))
10520 gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p
10521 (conv
->type
, DECL_CONTEXT (fn
)));
10522 z_candidate
*uc
= conv
->cand
;
10523 if (DECL_CONV_FN_P (uc
->fn
))
10532 /* Compare two candidates for overloading as described in
10533 [over.match.best]. Return values:
10535 1: cand1 is better than cand2
10536 -1: cand2 is better than cand1
10537 0: cand1 and cand2 are indistinguishable */
10540 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10541 tsubst_flags_t complain
)
10544 int off1
= 0, off2
= 0;
10548 /* Candidates that involve bad conversions are always worse than those
10550 if (cand1
->viable
> cand2
->viable
)
10552 if (cand1
->viable
< cand2
->viable
)
10555 /* If we have two pseudo-candidates for conversions to the same type,
10556 or two candidates for the same function, arbitrarily pick one. */
10557 if (cand1
->fn
== cand2
->fn
10558 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10561 /* Prefer a non-deleted function over an implicitly deleted move
10562 constructor or assignment operator. This differs slightly from the
10563 wording for issue 1402 (which says the move op is ignored by overload
10564 resolution), but this way produces better error messages. */
10565 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10566 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10567 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10569 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10570 && move_fn_p (cand1
->fn
))
10572 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10573 && move_fn_p (cand2
->fn
))
10577 /* a viable function F1
10578 is defined to be a better function than another viable function F2 if
10579 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10580 ICSi(F2), and then */
10582 /* for some argument j, ICSj(F1) is a better conversion sequence than
10585 /* For comparing static and non-static member functions, we ignore
10586 the implicit object parameter of the non-static function. The
10587 standard says to pretend that the static function has an object
10588 parm, but that won't work with operator overloading. */
10589 len
= cand1
->num_convs
;
10590 if (len
!= cand2
->num_convs
)
10592 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10593 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10595 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10596 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10597 /* We're comparing a near-match list constructor and a near-match
10598 non-list constructor. Just treat them as unordered. */
10601 gcc_assert (static_1
!= static_2
);
10612 /* Handle C++17 copy elision in [over.match.ctor] (direct-init) context. The
10613 standard currently says that only constructors are candidates, but if one
10614 copies a prvalue returned by a conversion function we want to treat the
10615 conversion as the candidate instead.
10617 Clang does something similar, as discussed at
10618 http://lists.isocpp.org/core/2017/10/3166.php
10619 http://lists.isocpp.org/core/2019/03/5721.php */
10620 int elided_tiebreaker
= 0;
10621 if (len
== 1 && cxx_dialect
>= cxx17
10622 && DECL_P (cand1
->fn
)
10623 && DECL_COMPLETE_CONSTRUCTOR_P (cand1
->fn
)
10624 && !(cand1
->flags
& LOOKUP_ONLYCONVERTING
))
10626 bool elided1
= joust_maybe_elide_copy (cand1
);
10627 bool elided2
= joust_maybe_elide_copy (cand2
);
10628 /* As a tiebreaker below we will prefer a constructor to a conversion
10629 operator exposed this way. */
10630 elided_tiebreaker
= elided2
- elided1
;
10633 for (i
= 0; i
< len
; ++i
)
10635 conversion
*t1
= cand1
->convs
[i
+ off1
];
10636 conversion
*t2
= cand2
->convs
[i
+ off2
];
10637 int comp
= compare_ics (t1
, t2
);
10641 if ((complain
& tf_warning
)
10643 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10644 == cr_std
+ cr_promotion
)
10645 && t1
->kind
== ck_std
10646 && t2
->kind
== ck_std
10647 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10648 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10649 && (TYPE_PRECISION (t1
->type
)
10650 == TYPE_PRECISION (t2
->type
))
10651 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10652 || (TREE_CODE (next_conversion (t1
)->type
)
10653 == ENUMERAL_TYPE
)))
10655 tree type
= next_conversion (t1
)->type
;
10657 struct z_candidate
*w
, *l
;
10659 type1
= t1
->type
, type2
= t2
->type
,
10660 w
= cand1
, l
= cand2
;
10662 type1
= t2
->type
, type2
= t1
->type
,
10663 w
= cand2
, l
= cand1
;
10667 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10668 type
, type1
, type2
);
10669 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10672 add_warning (w
, l
);
10675 if (winner
&& comp
!= winner
)
10684 /* warn about confusing overload resolution for user-defined conversions,
10685 either between a constructor and a conversion op, or between two
10687 if ((complain
& tf_warning
)
10688 && winner
&& warn_conversion
&& cand1
->second_conv
10689 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10690 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10692 struct z_candidate
*w
, *l
;
10693 bool give_warning
= false;
10696 w
= cand1
, l
= cand2
;
10698 w
= cand2
, l
= cand1
;
10700 /* We don't want to complain about `X::operator T1 ()'
10701 beating `X::operator T2 () const', when T2 is a no less
10702 cv-qualified version of T1. */
10703 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10704 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10706 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10707 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10709 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10714 if (!comp_ptr_ttypes (t
, f
))
10715 give_warning
= true;
10718 give_warning
= true;
10724 tree source
= source_type (w
->convs
[0]);
10725 if (INDIRECT_TYPE_P (source
))
10726 source
= TREE_TYPE (source
);
10727 auto_diagnostic_group d
;
10728 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10729 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10730 source
, w
->second_conv
->type
))
10732 inform (input_location
, " because conversion sequence for the argument is better");
10736 add_warning (w
, l
);
10742 /* Put this tiebreaker first, so that we don't try to look at second_conv of
10743 a constructor candidate that doesn't have one. */
10744 if (elided_tiebreaker
)
10745 return elided_tiebreaker
;
10747 /* DR 495 moved this tiebreaker above the template ones. */
10748 /* or, if not that,
10749 the context is an initialization by user-defined conversion (see
10750 _dcl.init_ and _over.match.user_) and the standard conversion
10751 sequence from the return type of F1 to the destination type (i.e.,
10752 the type of the entity being initialized) is a better conversion
10753 sequence than the standard conversion sequence from the return type
10754 of F2 to the destination type. */
10756 if (cand1
->second_conv
)
10758 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10763 /* or, if not that,
10764 F1 is a non-template function and F2 is a template function
10767 if (!cand1
->template_decl
&& cand2
->template_decl
)
10769 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10772 /* or, if not that,
10773 F1 and F2 are template functions and the function template for F1 is
10774 more specialized than the template for F2 according to the partial
10777 if (cand1
->template_decl
&& cand2
->template_decl
)
10779 winner
= more_specialized_fn
10780 (TI_TEMPLATE (cand1
->template_decl
),
10781 TI_TEMPLATE (cand2
->template_decl
),
10782 /* [temp.func.order]: The presence of unused ellipsis and default
10783 arguments has no effect on the partial ordering of function
10784 templates. add_function_candidate() will not have
10785 counted the "this" argument for constructors. */
10786 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10792 // or, if not that, F1 is more constrained than F2.
10793 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10795 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10800 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10801 if (deduction_guide_p (cand1
->fn
))
10803 gcc_assert (deduction_guide_p (cand2
->fn
));
10804 /* We distinguish between candidates from an explicit deduction guide and
10805 candidates built from a constructor based on DECL_ARTIFICIAL. */
10806 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10807 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10809 return art2
- art1
;
10813 /* Prefer the special copy guide over a declared copy/move
10815 if (copy_guide_p (cand1
->fn
))
10817 if (copy_guide_p (cand2
->fn
))
10820 /* Prefer a candidate generated from a non-template constructor. */
10821 int tg1
= template_guide_p (cand1
->fn
);
10822 int tg2
= template_guide_p (cand2
->fn
);
10828 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10829 for all arguments the corresponding parameters of F1 and F2 have the same
10830 type (CWG 2273/2277). */
10831 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10832 && !DECL_CONV_FN_P (cand1
->fn
)
10833 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10834 && !DECL_CONV_FN_P (cand2
->fn
))
10836 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10837 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10839 bool used1
= false;
10840 bool used2
= false;
10841 if (base1
== base2
)
10842 /* No difference. */;
10843 else if (DERIVED_FROM_P (base1
, base2
))
10845 else if (DERIVED_FROM_P (base2
, base1
))
10848 if (int diff
= used2
- used1
)
10850 for (i
= 0; i
< len
; ++i
)
10852 conversion
*t1
= cand1
->convs
[i
+ off1
];
10853 conversion
*t2
= cand2
->convs
[i
+ off2
];
10854 if (!same_type_p (t1
->type
, t2
->type
))
10862 /* Check whether we can discard a builtin candidate, either because we
10863 have two identical ones or matching builtin and non-builtin candidates.
10865 (Pedantically in the latter case the builtin which matched the user
10866 function should not be added to the overload set, but we spot it here.
10869 ... the builtin candidates include ...
10870 - do not have the same parameter type list as any non-template
10871 non-member candidate. */
10873 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10875 for (i
= 0; i
< len
; ++i
)
10876 if (!same_type_p (cand1
->convs
[i
]->type
,
10877 cand2
->convs
[i
]->type
))
10879 if (i
== cand1
->num_convs
)
10881 if (cand1
->fn
== cand2
->fn
)
10882 /* Two built-in candidates; arbitrarily pick one. */
10884 else if (identifier_p (cand1
->fn
))
10885 /* cand1 is built-in; prefer cand2. */
10888 /* cand2 is built-in; prefer cand1. */
10893 /* For candidates of a multi-versioned function, make the version with
10894 the highest priority win. This version will be checked for dispatching
10895 first. If this version can be inlined into the caller, the front-end
10896 will simply make a direct call to this function. */
10898 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10899 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10900 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10901 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10903 tree f1
= TREE_TYPE (cand1
->fn
);
10904 tree f2
= TREE_TYPE (cand2
->fn
);
10905 tree p1
= TYPE_ARG_TYPES (f1
);
10906 tree p2
= TYPE_ARG_TYPES (f2
);
10908 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10909 is possible that cand1->fn and cand2->fn are function versions but of
10910 different functions. Check types to see if they are versions of the same
10912 if (compparms (p1
, p2
)
10913 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10915 /* Always make the version with the higher priority, more
10916 specialized, win. */
10917 gcc_assert (targetm
.compare_version_priority
);
10918 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10925 /* If the two function declarations represent the same function (this can
10926 happen with declarations in multiple scopes and arg-dependent lookup),
10927 arbitrarily choose one. But first make sure the default args we're
10929 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10930 && equal_functions (cand1
->fn
, cand2
->fn
))
10932 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10933 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10935 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10937 for (i
= 0; i
< len
; ++i
)
10939 /* Don't crash if the fn is variadic. */
10942 parms1
= TREE_CHAIN (parms1
);
10943 parms2
= TREE_CHAIN (parms2
);
10947 parms1
= TREE_CHAIN (parms1
);
10949 parms2
= TREE_CHAIN (parms2
);
10951 for (; parms1
; ++i
)
10953 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10954 TREE_PURPOSE (parms2
)))
10958 if (complain
& tf_error
)
10960 auto_diagnostic_group d
;
10961 if (permerror (input_location
,
10962 "default argument mismatch in "
10963 "overload resolution"))
10965 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10966 " candidate 1: %q#F", cand1
->fn
);
10967 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10968 " candidate 2: %q#F", cand2
->fn
);
10975 add_warning (cand1
, cand2
);
10978 parms1
= TREE_CHAIN (parms1
);
10979 parms2
= TREE_CHAIN (parms2
);
10987 /* Extension: If the worst conversion for one candidate is better than the
10988 worst conversion for the other, take the first. */
10989 if (!pedantic
&& (complain
& tf_warning_or_error
))
10991 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
10992 struct z_candidate
*w
= 0, *l
= 0;
10994 for (i
= 0; i
< len
; ++i
)
10996 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
10997 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
10998 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
10999 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
11002 winner
= 1, w
= cand1
, l
= cand2
;
11004 winner
= -1, w
= cand2
, l
= cand1
;
11007 /* Don't choose a deleted function over ambiguity. */
11008 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
11012 auto_diagnostic_group d
;
11013 if (pedwarn (input_location
, 0,
11014 "ISO C++ says that these are ambiguous, even "
11015 "though the worst conversion for the first is "
11016 "better than the worst conversion for the second:"))
11018 print_z_candidate (input_location
, _("candidate 1:"), w
);
11019 print_z_candidate (input_location
, _("candidate 2:"), l
);
11023 add_warning (w
, l
);
11028 gcc_assert (!winner
);
11032 /* Given a list of candidates for overloading, find the best one, if any.
11033 This algorithm has a worst case of O(2n) (winner is last), and a best
11034 case of O(n/2) (totally ambiguous); much better than a sorting
11037 static struct z_candidate
*
11038 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
11040 struct z_candidate
*champ
= candidates
, *challenger
;
11042 int champ_compared_to_predecessor
= 0;
11044 /* Walk through the list once, comparing each current champ to the next
11045 candidate, knocking out a candidate or two with each comparison. */
11047 for (challenger
= champ
->next
; challenger
; )
11049 fate
= joust (champ
, challenger
, 0, complain
);
11051 challenger
= challenger
->next
;
11056 champ
= challenger
->next
;
11059 champ_compared_to_predecessor
= 0;
11063 champ
= challenger
;
11064 champ_compared_to_predecessor
= 1;
11067 challenger
= champ
->next
;
11071 /* Make sure the champ is better than all the candidates it hasn't yet
11072 been compared to. */
11074 for (challenger
= candidates
;
11075 challenger
!= champ
11076 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
11077 challenger
= challenger
->next
)
11079 fate
= joust (champ
, challenger
, 0, complain
);
11087 /* Returns nonzero if things of type FROM can be converted to TO. */
11090 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
11092 tree arg
= NULL_TREE
;
11093 /* implicit_conversion only considers user-defined conversions
11094 if it has an expression for the call argument list. */
11095 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
11096 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
11097 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
11100 /* Returns nonzero if things of type FROM can be converted to TO with a
11101 standard conversion. */
11104 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
11106 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
11109 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
11112 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
11113 tsubst_flags_t complain
)
11119 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11120 p
= conversion_obstack_alloc (0);
11121 /* We want to discard any access checks done for this test,
11122 as we might not be in the appropriate access context and
11123 we'll do the check again when we actually perform the
11125 push_deferring_access_checks (dk_deferred
);
11127 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11129 ok_p
= (t
&& !t
->bad_p
);
11131 /* Discard the access checks now. */
11132 pop_deferring_access_checks ();
11133 /* Free all the conversions we allocated. */
11134 obstack_free (&conversion_obstack
, p
);
11139 /* Like can_convert_arg, but allows dubious conversions as well. */
11142 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
11143 tsubst_flags_t complain
)
11148 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11149 p
= conversion_obstack_alloc (0);
11150 /* Try to perform the conversion. */
11151 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11153 /* Free all the conversions we allocated. */
11154 obstack_free (&conversion_obstack
, p
);
11159 /* Convert EXPR to TYPE. Return the converted expression.
11161 Note that we allow bad conversions here because by the time we get to
11162 this point we are committed to doing the conversion. If we end up
11163 doing a bad conversion, convert_like will complain. */
11166 perform_implicit_conversion_flags (tree type
, tree expr
,
11167 tsubst_flags_t complain
, int flags
)
11171 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
11173 if (TYPE_REF_P (type
))
11174 expr
= mark_lvalue_use (expr
);
11176 expr
= mark_rvalue_use (expr
);
11178 if (error_operand_p (expr
))
11179 return error_mark_node
;
11181 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11182 p
= conversion_obstack_alloc (0);
11184 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11185 /*c_cast_p=*/false,
11190 if (complain
& tf_error
)
11192 /* If expr has unknown type, then it is an overloaded function.
11193 Call instantiate_type to get good error messages. */
11194 if (TREE_TYPE (expr
) == unknown_type_node
)
11195 instantiate_type (type
, expr
, complain
);
11196 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
11197 /* We gave an error. */;
11200 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
11201 gcc_rich_location
rich_loc (loc
, &label
);
11202 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
11203 expr
, TREE_TYPE (expr
), type
);
11206 expr
= error_mark_node
;
11208 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11210 /* In a template, we are only concerned about determining the
11211 type of non-dependent expressions, so we do not have to
11212 perform the actual conversion. But for initializers, we
11213 need to be able to perform it at instantiation
11214 (or instantiate_non_dependent_expr) time. */
11215 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11216 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11217 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11218 if (flags
& LOOKUP_NO_NARROWING
)
11219 IMPLICIT_CONV_EXPR_BRACED_INIT (expr
) = true;
11222 expr
= convert_like (conv
, expr
, complain
);
11224 /* Free all the conversions we allocated. */
11225 obstack_free (&conversion_obstack
, p
);
11231 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11233 return perform_implicit_conversion_flags (type
, expr
, complain
,
11237 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11238 permitted. If the conversion is valid, the converted expression is
11239 returned. Otherwise, NULL_TREE is returned, except in the case
11240 that TYPE is a class type; in that case, an error is issued. If
11241 C_CAST_P is true, then this direct-initialization is taking
11242 place as part of a static_cast being attempted as part of a C-style
11246 perform_direct_initialization_if_possible (tree type
,
11249 tsubst_flags_t complain
)
11254 if (type
== error_mark_node
|| error_operand_p (expr
))
11255 return error_mark_node
;
11258 If the destination type is a (possibly cv-qualified) class type:
11260 -- If the initialization is direct-initialization ...,
11261 constructors are considered. ... If no constructor applies, or
11262 the overload resolution is ambiguous, the initialization is
11264 if (CLASS_TYPE_P (type
))
11266 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
11267 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11268 &args
, type
, LOOKUP_NORMAL
, complain
);
11269 release_tree_vector (args
);
11270 return build_cplus_new (type
, expr
, complain
);
11273 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11274 p
= conversion_obstack_alloc (0);
11276 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11278 LOOKUP_NORMAL
, complain
);
11279 if (!conv
|| conv
->bad_p
)
11281 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11283 /* In a template, we are only concerned about determining the
11284 type of non-dependent expressions, so we do not have to
11285 perform the actual conversion. But for initializers, we
11286 need to be able to perform it at instantiation
11287 (or instantiate_non_dependent_expr) time. */
11288 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11289 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11292 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11293 /*issue_conversion_warnings=*/false,
11297 /* Free all the conversions we allocated. */
11298 obstack_free (&conversion_obstack
, p
);
11303 /* When initializing a reference that lasts longer than a full-expression,
11304 this special rule applies:
11308 The temporary to which the reference is bound or the temporary
11309 that is the complete object to which the reference is bound
11310 persists for the lifetime of the reference.
11312 The temporaries created during the evaluation of the expression
11313 initializing the reference, except the temporary to which the
11314 reference is bound, are destroyed at the end of the
11315 full-expression in which they are created.
11317 In that case, we store the converted expression into a new
11318 VAR_DECL in a new scope.
11320 However, we want to be careful not to create temporaries when
11321 they are not required. For example, given:
11324 struct D : public B {};
11328 there is no need to copy the return value from "f"; we can just
11329 extend its lifetime. Similarly, given:
11332 struct T { operator S(); };
11336 we can extend the lifetime of the return value of the conversion
11339 The next several functions are involved in this lifetime extension. */
11341 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11342 reference is being bound to a temporary. Create and return a new
11343 VAR_DECL with the indicated TYPE; this variable will store the value to
11344 which the reference is bound. */
11347 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11349 tree var
= create_temporary_var (type
);
11351 /* Register the variable. */
11353 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11355 /* Namespace-scope or local static; give it a mangled name. */
11357 /* If an initializer is visible to multiple translation units, those
11358 translation units must agree on the addresses of the
11359 temporaries. Therefore the temporaries must be given a consistent name
11360 and vague linkage. The mangled name of a temporary is the name of the
11361 non-temporary object in whose initializer they appear, prefixed with
11362 GR and suffixed with a sequence number mangled using the usual rules
11363 for a seq-id. Temporaries are numbered with a pre-order, depth-first,
11364 left-to-right walk of the complete initializer. */
11366 TREE_STATIC (var
) = TREE_STATIC (decl
);
11367 TREE_PUBLIC (var
) = TREE_PUBLIC (decl
);
11368 if (vague_linkage_p (decl
))
11369 comdat_linkage (var
);
11371 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11372 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11374 tree name
= mangle_ref_init_variable (decl
);
11375 DECL_NAME (var
) = name
;
11376 SET_DECL_ASSEMBLER_NAME (var
, name
);
11379 /* Create a new cleanup level if necessary. */
11380 maybe_push_cleanup_level (type
);
11382 return pushdecl (var
);
11385 /* EXPR is the initializer for a variable DECL of reference or
11386 std::initializer_list type. Create, push and return a new VAR_DECL
11387 for the initializer so that it will live as long as DECL. Any
11388 cleanup for the new variable is returned through CLEANUP, and the
11389 code to initialize the new variable is returned through INITP. */
11392 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11399 /* Create the temporary variable. */
11400 type
= TREE_TYPE (expr
);
11401 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11402 layout_decl (var
, 0);
11403 /* If the rvalue is the result of a function call it will be
11404 a TARGET_EXPR. If it is some other construct (such as a
11405 member access expression where the underlying object is
11406 itself the result of a function call), turn it into a
11407 TARGET_EXPR here. It is important that EXPR be a
11408 TARGET_EXPR below since otherwise the INIT_EXPR will
11409 attempt to make a bitwise copy of EXPR to initialize
11411 if (TREE_CODE (expr
) != TARGET_EXPR
)
11412 expr
= get_target_expr (expr
);
11414 if (TREE_CODE (decl
) == FIELD_DECL
11415 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11417 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11418 "until the constructor exits", decl
);
11419 TREE_NO_WARNING (decl
) = true;
11422 /* Recursively extend temps in this initializer. */
11423 TARGET_EXPR_INITIAL (expr
)
11424 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11426 /* Any reference temp has a non-trivial initializer. */
11427 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11429 /* If the initializer is constant, put it in DECL_INITIAL so we get
11430 static initialization and use in constant expressions. */
11431 init
= maybe_constant_init (expr
);
11432 /* As in store_init_value. */
11433 init
= cp_fully_fold (init
);
11434 if (TREE_CONSTANT (init
))
11436 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11438 /* 5.19 says that a constant expression can include an
11439 lvalue-rvalue conversion applied to "a glvalue of literal type
11440 that refers to a non-volatile temporary object initialized
11441 with a constant expression". Rather than try to communicate
11442 that this VAR_DECL is a temporary, just mark it constexpr. */
11443 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11444 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11445 TREE_CONSTANT (var
) = true;
11446 TREE_READONLY (var
) = true;
11448 DECL_INITIAL (var
) = init
;
11452 /* Create the INIT_EXPR that will initialize the temporary
11454 init
= split_nonconstant_init (var
, expr
);
11455 if (at_function_scope_p ())
11457 add_decl_expr (var
);
11459 if (TREE_STATIC (var
))
11460 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11463 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11465 vec_safe_push (*cleanups
, cleanup
);
11468 /* We must be careful to destroy the temporary only
11469 after its initialization has taken place. If the
11470 initialization throws an exception, then the
11471 destructor should not be run. We cannot simply
11472 transform INIT into something like:
11474 (INIT, ({ CLEANUP_STMT; }))
11476 because emit_local_var always treats the
11477 initializer as a full-expression. Thus, the
11478 destructor would run too early; it would run at the
11479 end of initializing the reference variable, rather
11480 than at the end of the block enclosing the
11481 reference variable.
11483 The solution is to pass back a cleanup expression
11484 which the caller is responsible for attaching to
11485 the statement tree. */
11489 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11490 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11492 if (CP_DECL_THREAD_LOCAL_P (var
))
11493 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11496 static_aggregates
= tree_cons (NULL_TREE
, var
,
11497 static_aggregates
);
11500 /* Check whether the dtor is callable. */
11501 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11503 /* Avoid -Wunused-variable warning (c++/38958). */
11504 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11506 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11512 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11513 initializing a variable of that TYPE. */
11516 initialize_reference (tree type
, tree expr
,
11517 int flags
, tsubst_flags_t complain
)
11521 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
11523 if (type
== error_mark_node
|| error_operand_p (expr
))
11524 return error_mark_node
;
11526 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11527 p
= conversion_obstack_alloc (0);
11529 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11531 if (!conv
|| conv
->bad_p
)
11533 if (complain
& tf_error
)
11536 convert_like (conv
, expr
, complain
);
11537 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11538 && !TYPE_REF_IS_RVALUE (type
)
11539 && !lvalue_p (expr
))
11540 error_at (loc
, "invalid initialization of non-const reference of "
11541 "type %qH from an rvalue of type %qI",
11542 type
, TREE_TYPE (expr
));
11544 error_at (loc
, "invalid initialization of reference of type "
11545 "%qH from expression of type %qI", type
,
11548 return error_mark_node
;
11551 if (conv
->kind
== ck_ref_bind
)
11552 /* Perform the conversion. */
11553 expr
= convert_like (conv
, expr
, complain
);
11554 else if (conv
->kind
== ck_ambig
)
11555 /* We gave an error in build_user_type_conversion_1. */
11556 expr
= error_mark_node
;
11558 gcc_unreachable ();
11560 /* Free all the conversions we allocated. */
11561 obstack_free (&conversion_obstack
, p
);
11566 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11567 which is bound either to a reference or a std::initializer_list. */
11570 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11575 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11577 TREE_OPERAND (sub
, 1)
11578 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11581 if (TREE_CODE (sub
) != ADDR_EXPR
)
11583 /* Deal with binding to a subobject. */
11584 for (p
= &TREE_OPERAND (sub
, 0);
11585 (TREE_CODE (*p
) == COMPONENT_REF
11586 || TREE_CODE (*p
) == ARRAY_REF
); )
11587 p
= &TREE_OPERAND (*p
, 0);
11588 if (TREE_CODE (*p
) == TARGET_EXPR
)
11590 tree subinit
= NULL_TREE
;
11591 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11592 recompute_tree_invariant_for_addr_expr (sub
);
11594 init
= fold_convert (TREE_TYPE (init
), sub
);
11596 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11601 /* INIT is part of the initializer for DECL. If there are any
11602 reference or initializer lists being initialized, extend their
11603 lifetime to match that of DECL. */
11606 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11608 tree type
= TREE_TYPE (init
);
11609 if (processing_template_decl
)
11611 if (TYPE_REF_P (type
))
11612 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11616 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11617 ctor
= TARGET_EXPR_INITIAL (ctor
);
11618 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11620 if (is_std_init_list (type
))
11622 /* The temporary array underlying a std::initializer_list
11623 is handled like a reference temporary. */
11624 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11625 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11626 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11631 constructor_elt
*p
;
11632 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11633 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11634 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11636 recompute_constructor_flags (ctor
);
11637 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11638 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11645 /* Returns true iff an initializer for TYPE could contain temporaries that
11646 need to be extended because they are bound to references or
11647 std::initializer_list. */
11650 type_has_extended_temps (tree type
)
11652 type
= strip_array_types (type
);
11653 if (TYPE_REF_P (type
))
11655 if (CLASS_TYPE_P (type
))
11657 if (is_std_init_list (type
))
11659 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11660 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11661 if (type_has_extended_temps (TREE_TYPE (f
)))
11667 /* Returns true iff TYPE is some variant of std::initializer_list. */
11670 is_std_init_list (tree type
)
11672 if (!TYPE_P (type
))
11674 if (cxx_dialect
== cxx98
)
11676 /* Look through typedefs. */
11677 type
= TYPE_MAIN_VARIANT (type
);
11678 return (CLASS_TYPE_P (type
)
11679 && CP_TYPE_CONTEXT (type
) == std_node
11680 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11683 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11684 will accept an argument list of a single std::initializer_list<T>. */
11687 is_list_ctor (tree decl
)
11689 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11692 if (!args
|| args
== void_list_node
)
11695 arg
= non_reference (TREE_VALUE (args
));
11696 if (!is_std_init_list (arg
))
11699 args
= TREE_CHAIN (args
);
11701 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11702 /* There are more non-defaulted parms. */
11708 #include "gt-cp-call.h"