1 /* Functions related to invoking -*- C++ -*- methods and overloaded functions.
2 Copyright (C) 1987-2019 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com) and
4 modified by Brendan Kehoe (brendan@cygnus.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* High-level class interface. */
27 #include "coretypes.h"
31 #include "stringpool.h"
33 #include "stor-layout.h"
34 #include "trans-mem.h"
39 #include "langhooks.h"
40 #include "c-family/c-objc.h"
41 #include "internal-fn.h"
42 #include "stringpool.h"
44 #include "gcc-rich-location.h"
46 /* The various kinds of conversion. */
48 enum conversion_kind
{
65 /* The rank of the conversion. Order of the enumerals matters; better
66 conversions should come earlier in the list. */
68 enum conversion_rank
{
79 /* An implicit conversion sequence, in the sense of [over.best.ics].
80 The first conversion to be performed is at the end of the chain.
81 That conversion is always a cr_identity conversion. */
84 /* The kind of conversion represented by this step. */
86 /* The rank of this conversion. */
88 BOOL_BITFIELD user_conv_p
: 1;
89 BOOL_BITFIELD ellipsis_p
: 1;
90 BOOL_BITFIELD this_p
: 1;
91 /* True if this conversion would be permitted with a bending of
92 language standards, e.g. disregarding pointer qualifiers or
93 converting integers to pointers. */
94 BOOL_BITFIELD bad_p
: 1;
95 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
96 temporary should be created to hold the result of the
97 conversion. If KIND is ck_ambig or ck_user, true means force
98 copy-initialization. */
99 BOOL_BITFIELD need_temporary_p
: 1;
100 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
101 from a pointer-to-derived to pointer-to-base is being performed. */
102 BOOL_BITFIELD base_p
: 1;
103 /* If KIND is ck_ref_bind, true when either an lvalue reference is
104 being bound to an lvalue expression or an rvalue reference is
105 being bound to an rvalue expression. If KIND is ck_rvalue or ck_base,
106 true when we are treating an lvalue as an rvalue (12.8p33). If
107 ck_identity, we will be binding a reference directly or decaying to
109 BOOL_BITFIELD rvaluedness_matches_p
: 1;
110 BOOL_BITFIELD check_narrowing
: 1;
111 /* Whether check_narrowing should only check TREE_CONSTANTs; used
112 in build_converted_constant_expr. */
113 BOOL_BITFIELD check_narrowing_const_only
: 1;
114 /* The type of the expression resulting from the conversion. */
117 /* The next conversion in the chain. Since the conversions are
118 arranged from outermost to innermost, the NEXT conversion will
119 actually be performed before this conversion. This variant is
120 used only when KIND is neither ck_identity, ck_ambig nor
121 ck_list. Please use the next_conversion function instead
122 of using this field directly. */
124 /* The expression at the beginning of the conversion chain. This
125 variant is used only if KIND is ck_identity or ck_ambig. */
127 /* The array of conversions for an initializer_list, so this
128 variant is used only when KIN D is ck_list. */
131 /* The function candidate corresponding to this conversion
132 sequence. This field is only used if KIND is ck_user. */
133 struct z_candidate
*cand
;
136 #define CONVERSION_RANK(NODE) \
137 ((NODE)->bad_p ? cr_bad \
138 : (NODE)->ellipsis_p ? cr_ellipsis \
139 : (NODE)->user_conv_p ? cr_user \
142 #define BAD_CONVERSION_RANK(NODE) \
143 ((NODE)->ellipsis_p ? cr_ellipsis \
144 : (NODE)->user_conv_p ? cr_user \
147 static struct obstack conversion_obstack
;
148 static bool conversion_obstack_initialized
;
149 struct rejection_reason
;
151 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
152 static int equal_functions (tree
, tree
);
153 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
155 static int compare_ics (conversion
*, conversion
*);
156 static void maybe_warn_class_memaccess (location_t
, tree
,
157 const vec
<tree
, va_gc
> *);
158 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
159 #define convert_like(CONV, EXPR, COMPLAIN) \
160 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \
161 /*issue_conversion_warnings=*/true, \
162 /*c_cast_p=*/false, (COMPLAIN))
163 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
164 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \
165 /*issue_conversion_warnings=*/true, \
166 /*c_cast_p=*/false, (COMPLAIN))
167 static tree
convert_like_real (conversion
*, tree
, tree
, int, bool,
168 bool, tsubst_flags_t
);
169 static void op_error (const op_location_t
&, enum tree_code
, enum tree_code
,
170 tree
, tree
, tree
, bool);
171 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
173 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
174 static void print_z_candidates (location_t
, struct z_candidate
*);
175 static tree
build_this (tree
);
176 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
177 static bool any_strictly_viable (struct z_candidate
*);
178 static struct z_candidate
*add_template_candidate
179 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
180 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
181 static struct z_candidate
*add_template_candidate_real
182 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
183 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
184 static void add_builtin_candidates
185 (struct z_candidate
**, enum tree_code
, enum tree_code
,
186 tree
, tree
*, int, tsubst_flags_t
);
187 static void add_builtin_candidate
188 (struct z_candidate
**, enum tree_code
, enum tree_code
,
189 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
190 static bool is_complete (tree
);
191 static void build_builtin_candidate
192 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
193 int, tsubst_flags_t
);
194 static struct z_candidate
*add_conv_candidate
195 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
196 tree
, tsubst_flags_t
);
197 static struct z_candidate
*add_function_candidate
198 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
199 tree
, int, conversion
**, tsubst_flags_t
);
200 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
202 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
204 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
205 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
206 static conversion
*next_conversion (conversion
*);
207 static bool is_subseq (conversion
*, conversion
*);
208 static conversion
*maybe_handle_ref_bind (conversion
**);
209 static void maybe_handle_implicit_object (conversion
**);
210 static struct z_candidate
*add_candidate
211 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
212 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
213 static tree
source_type (conversion
*);
214 static void add_warning (struct z_candidate
*, struct z_candidate
*);
215 static bool reference_compatible_p (tree
, tree
);
216 static conversion
*direct_reference_binding (tree
, conversion
*);
217 static bool promoted_arithmetic_type_p (tree
);
218 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
219 static char *name_as_c_string (tree
, tree
, bool *);
220 static tree
prep_operand (tree
);
221 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
222 bool, tree
, tree
, int, struct z_candidate
**,
224 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
225 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
227 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
228 NAME can take many forms... */
231 check_dtor_name (tree basetype
, tree name
)
233 /* Just accept something we've already complained about. */
234 if (name
== error_mark_node
)
237 if (TREE_CODE (name
) == TYPE_DECL
)
238 name
= TREE_TYPE (name
);
239 else if (TYPE_P (name
))
241 else if (identifier_p (name
))
243 if ((MAYBE_CLASS_TYPE_P (basetype
)
244 || TREE_CODE (basetype
) == ENUMERAL_TYPE
)
245 && name
== constructor_name (basetype
))
248 name
= get_type_value (name
);
254 template <class T> struct S { ~S(); };
258 NAME will be a class template. */
259 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
263 if (!name
|| name
== error_mark_node
)
265 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
268 /* We want the address of a function or method. We avoid creating a
269 pointer-to-member function. */
272 build_addr_func (tree function
, tsubst_flags_t complain
)
274 tree type
= TREE_TYPE (function
);
276 /* We have to do these by hand to avoid real pointer to member
278 if (TREE_CODE (type
) == METHOD_TYPE
)
280 if (TREE_CODE (function
) == OFFSET_REF
)
282 tree object
= build_address (TREE_OPERAND (function
, 0));
283 return get_member_function_from_ptrfunc (&object
,
284 TREE_OPERAND (function
, 1),
287 function
= build_address (function
);
290 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
295 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
296 POINTER_TYPE to those. Note, pointer to member function types
297 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
298 two variants. build_call_a is the primitive taking an array of
299 arguments, while build_call_n is a wrapper that handles varargs. */
302 build_call_n (tree function
, int n
, ...)
305 return build_call_a (function
, 0, NULL
);
308 tree
*argarray
= XALLOCAVEC (tree
, n
);
313 for (i
= 0; i
< n
; i
++)
314 argarray
[i
] = va_arg (ap
, tree
);
316 return build_call_a (function
, n
, argarray
);
320 /* Update various flags in cfun and the call itself based on what is being
321 called. Split out of build_call_a so that bot_manip can use it too. */
324 set_flags_from_callee (tree call
)
326 /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */
327 tree decl
= cp_get_callee_fndecl_nofold (call
);
329 /* We check both the decl and the type; a function may be known not to
330 throw without being declared throw(). */
331 bool nothrow
= decl
&& TREE_NOTHROW (decl
);
332 tree callee
= cp_get_callee (call
);
334 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (callee
)));
335 else if (TREE_CODE (call
) == CALL_EXPR
336 && internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
339 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
340 cp_function_chain
->can_throw
= 1;
342 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
343 current_function_returns_abnormally
= 1;
345 TREE_NOTHROW (call
) = nothrow
;
349 build_call_a (tree function
, int n
, tree
*argarray
)
356 function
= build_addr_func (function
, tf_warning_or_error
);
358 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
359 fntype
= TREE_TYPE (TREE_TYPE (function
));
360 gcc_assert (FUNC_OR_METHOD_TYPE_P (fntype
));
361 result_type
= TREE_TYPE (fntype
);
362 /* An rvalue has no cv-qualifiers. */
363 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
364 result_type
= cv_unqualified (result_type
);
366 function
= build_call_array_loc (input_location
,
367 result_type
, function
, n
, argarray
);
368 set_flags_from_callee (function
);
370 decl
= get_callee_fndecl (function
);
372 if (decl
&& !TREE_USED (decl
))
374 /* We invoke build_call directly for several library
375 functions. These may have been declared normally if
376 we're building libgcc, so we can't just check
378 gcc_assert (DECL_ARTIFICIAL (decl
)
379 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
384 require_complete_eh_spec_types (fntype
, decl
);
386 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
388 /* Don't pass empty class objects by value. This is useful
389 for tags in STL, which are used to control overload resolution.
390 We don't need to handle other cases of copying empty classes. */
391 if (!decl
|| !fndecl_built_in_p (decl
))
392 for (i
= 0; i
< n
; i
++)
394 tree arg
= CALL_EXPR_ARG (function
, i
);
395 if (is_empty_class (TREE_TYPE (arg
))
396 && simple_empty_class_p (TREE_TYPE (arg
), arg
, INIT_EXPR
))
398 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
399 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
400 CALL_EXPR_ARG (function
, i
) = arg
;
407 /* New overloading code. */
411 struct candidate_warning
{
413 candidate_warning
*next
;
416 /* Information for providing diagnostics about why overloading failed. */
418 enum rejection_reason_code
{
421 rr_explicit_conversion
,
422 rr_template_conversion
,
424 rr_bad_arg_conversion
,
425 rr_template_unification
,
428 rr_constraint_failure
431 struct conversion_info
{
432 /* The index of the argument, 0-based. */
434 /* The actual argument or its type. */
436 /* The type of the parameter. */
438 /* The location of the argument. */
442 struct rejection_reason
{
443 enum rejection_reason_code code
;
445 /* Information about an arity mismatch. */
447 /* The expected number of arguments. */
449 /* The actual number of arguments in the call. */
451 /* Whether the call was a varargs call. */
454 /* Information about an argument conversion mismatch. */
455 struct conversion_info conversion
;
456 /* Same, but for bad argument conversions. */
457 struct conversion_info bad_conversion
;
458 /* Information about template unification failures. These are the
459 parameters passed to fn_type_unification. */
467 unification_kind_t strict
;
469 } template_unification
;
470 /* Information about template instantiation failures. These are the
471 parameters passed to instantiate_template. */
475 } template_instantiation
;
480 /* The FUNCTION_DECL that will be called if this candidate is
481 selected by overload resolution. */
483 /* If not NULL_TREE, the first argument to use when calling this
486 /* The rest of the arguments to use when calling this function. If
487 there are no further arguments this may be NULL or it may be an
489 const vec
<tree
, va_gc
> *args
;
490 /* The implicit conversion sequences for each of the arguments to
493 /* The number of implicit conversion sequences. */
495 /* If FN is a user-defined conversion, the standard conversion
496 sequence from the type returned by FN to the desired destination
498 conversion
*second_conv
;
499 struct rejection_reason
*reason
;
500 /* If FN is a member function, the binfo indicating the path used to
501 qualify the name of FN at the call site. This path is used to
502 determine whether or not FN is accessible if it is selected by
503 overload resolution. The DECL_CONTEXT of FN will always be a
504 (possibly improper) base of this binfo. */
506 /* If FN is a non-static member function, the binfo indicating the
507 subobject to which the `this' pointer should be converted if FN
508 is selected by overload resolution. The type pointed to by
509 the `this' pointer must correspond to the most derived class
510 indicated by the CONVERSION_PATH. */
511 tree conversion_path
;
514 candidate_warning
*warnings
;
518 /* The flags active in add_candidate. */
522 /* Returns true iff T is a null pointer constant in the sense of
526 null_ptr_cst_p (tree t
)
528 tree type
= TREE_TYPE (t
);
532 A null pointer constant is an integer literal ([lex.icon]) with value
533 zero or a prvalue of type std::nullptr_t. */
534 if (NULLPTR_TYPE_P (type
))
537 if (cxx_dialect
>= cxx11
)
539 STRIP_ANY_LOCATION_WRAPPER (t
);
541 /* Core issue 903 says only literal 0 is a null pointer constant. */
542 if (TREE_CODE (t
) == INTEGER_CST
543 && !TREE_OVERFLOW (t
)
544 && TREE_CODE (type
) == INTEGER_TYPE
546 && !char_type_p (type
))
549 else if (CP_INTEGRAL_TYPE_P (type
))
551 t
= fold_non_dependent_expr (t
, tf_none
);
553 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
560 /* Returns true iff T is a null member pointer value (4.11). */
563 null_member_pointer_value_p (tree t
)
565 tree type
= TREE_TYPE (t
);
568 else if (TYPE_PTRMEMFUNC_P (type
))
569 return (TREE_CODE (t
) == CONSTRUCTOR
570 && CONSTRUCTOR_NELTS (t
)
571 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
572 else if (TYPE_PTRDATAMEM_P (type
))
573 return integer_all_onesp (t
);
578 /* Returns nonzero if PARMLIST consists of only default parms,
579 ellipsis, and/or undeduced parameter packs. */
582 sufficient_parms_p (const_tree parmlist
)
584 for (; parmlist
&& parmlist
!= void_list_node
;
585 parmlist
= TREE_CHAIN (parmlist
))
586 if (!TREE_PURPOSE (parmlist
)
587 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
592 /* Allocate N bytes of memory from the conversion obstack. The memory
593 is zeroed before being returned. */
596 conversion_obstack_alloc (size_t n
)
599 if (!conversion_obstack_initialized
)
601 gcc_obstack_init (&conversion_obstack
);
602 conversion_obstack_initialized
= true;
604 p
= obstack_alloc (&conversion_obstack
, n
);
609 /* Allocate rejection reasons. */
611 static struct rejection_reason
*
612 alloc_rejection (enum rejection_reason_code code
)
614 struct rejection_reason
*p
;
615 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
620 static struct rejection_reason
*
621 arity_rejection (tree first_arg
, int expected
, int actual
)
623 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
624 int adjust
= first_arg
!= NULL_TREE
;
625 r
->u
.arity
.expected
= expected
- adjust
;
626 r
->u
.arity
.actual
= actual
- adjust
;
630 static struct rejection_reason
*
631 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
634 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
635 int adjust
= first_arg
!= NULL_TREE
;
636 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
637 r
->u
.conversion
.from
= from
;
638 r
->u
.conversion
.to_type
= to
;
639 r
->u
.conversion
.loc
= loc
;
643 static struct rejection_reason
*
644 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
647 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
648 int adjust
= first_arg
!= NULL_TREE
;
649 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
650 r
->u
.bad_conversion
.from
= from
;
651 r
->u
.bad_conversion
.to_type
= to
;
652 r
->u
.bad_conversion
.loc
= loc
;
656 static struct rejection_reason
*
657 explicit_conversion_rejection (tree from
, tree to
)
659 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
660 r
->u
.conversion
.n_arg
= 0;
661 r
->u
.conversion
.from
= from
;
662 r
->u
.conversion
.to_type
= to
;
663 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
667 static struct rejection_reason
*
668 template_conversion_rejection (tree from
, tree to
)
670 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
671 r
->u
.conversion
.n_arg
= 0;
672 r
->u
.conversion
.from
= from
;
673 r
->u
.conversion
.to_type
= to
;
674 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
678 static struct rejection_reason
*
679 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
680 const tree
*args
, unsigned int nargs
,
681 tree return_type
, unification_kind_t strict
,
684 size_t args_n_bytes
= sizeof (*args
) * nargs
;
685 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
686 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
687 r
->u
.template_unification
.tmpl
= tmpl
;
688 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
689 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
690 /* Copy args to our own storage. */
691 memcpy (args1
, args
, args_n_bytes
);
692 r
->u
.template_unification
.args
= args1
;
693 r
->u
.template_unification
.nargs
= nargs
;
694 r
->u
.template_unification
.return_type
= return_type
;
695 r
->u
.template_unification
.strict
= strict
;
696 r
->u
.template_unification
.flags
= flags
;
700 static struct rejection_reason
*
701 template_unification_error_rejection (void)
703 return alloc_rejection (rr_template_unification
);
706 static struct rejection_reason
*
707 invalid_copy_with_fn_template_rejection (void)
709 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
713 static struct rejection_reason
*
714 inherited_ctor_rejection (void)
716 struct rejection_reason
*r
= alloc_rejection (rr_inherited_ctor
);
720 // Build a constraint failure record, saving information into the
721 // template_instantiation field of the rejection. If FN is not a template
722 // declaration, the TMPL member is the FN declaration and TARGS is empty.
724 static struct rejection_reason
*
725 constraint_failure (tree fn
)
727 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
728 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
730 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
731 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
735 r
->u
.template_instantiation
.tmpl
= fn
;
736 r
->u
.template_instantiation
.targs
= NULL_TREE
;
741 /* Dynamically allocate a conversion. */
744 alloc_conversion (conversion_kind kind
)
747 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
752 /* Make sure that all memory on the conversion obstack has been
756 validate_conversion_obstack (void)
758 if (conversion_obstack_initialized
)
759 gcc_assert ((obstack_next_free (&conversion_obstack
)
760 == obstack_base (&conversion_obstack
)));
763 /* Dynamically allocate an array of N conversions. */
766 alloc_conversions (size_t n
)
768 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
772 build_conv (conversion_kind code
, tree type
, conversion
*from
)
775 conversion_rank rank
= CONVERSION_RANK (from
);
777 /* Note that the caller is responsible for filling in t->cand for
778 user-defined conversions. */
779 t
= alloc_conversion (code
);
803 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
804 t
->bad_p
= from
->bad_p
;
809 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
810 specialization of std::initializer_list<T>, if such a conversion is
814 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
816 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
817 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
818 conversion
**subconvs
= alloc_conversions (len
);
823 /* Within a list-initialization we can have more user-defined
825 flags
&= ~LOOKUP_NO_CONVERSION
;
826 /* But no narrowing conversions. */
827 flags
|= LOOKUP_NO_NARROWING
;
829 /* Can't make an array of these types. */
830 if (TYPE_REF_P (elttype
)
831 || TREE_CODE (elttype
) == FUNCTION_TYPE
832 || VOID_TYPE_P (elttype
))
835 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
838 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
839 false, flags
, complain
);
846 t
= alloc_conversion (ck_list
);
848 t
->u
.list
= subconvs
;
851 for (i
= 0; i
< len
; ++i
)
853 conversion
*sub
= subconvs
[i
];
854 if (sub
->rank
> t
->rank
)
856 if (sub
->user_conv_p
)
857 t
->user_conv_p
= true;
865 /* Return the next conversion of the conversion chain (if applicable),
866 or NULL otherwise. Please use this function instead of directly
867 accessing fields of struct conversion. */
870 next_conversion (conversion
*conv
)
873 || conv
->kind
== ck_identity
874 || conv
->kind
== ck_ambig
875 || conv
->kind
== ck_list
)
880 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
881 is a valid aggregate initializer for array type ATYPE. */
884 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
887 tree elttype
= TREE_TYPE (atype
);
888 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
890 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
892 if (TREE_CODE (elttype
) == ARRAY_TYPE
893 && TREE_CODE (val
) == CONSTRUCTOR
)
894 ok
= can_convert_array (elttype
, val
, flags
, complain
);
896 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
904 /* Helper for build_aggr_conv. Return true if FIELD is in PSET, or if
905 FIELD has ANON_AGGR_TYPE_P and any initializable field in there recursively
909 field_in_pset (hash_set
<tree
, true> &pset
, tree field
)
911 if (pset
.contains (field
))
913 if (ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
914 for (field
= TYPE_FIELDS (TREE_TYPE (field
));
915 field
; field
= DECL_CHAIN (field
))
917 field
= next_initializable_field (field
);
918 if (field
== NULL_TREE
)
920 if (field_in_pset (pset
, field
))
926 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
927 aggregate class, if such a conversion is possible. */
930 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
932 unsigned HOST_WIDE_INT i
= 0;
934 tree field
= next_initializable_field (TYPE_FIELDS (type
));
935 tree empty_ctor
= NULL_TREE
;
936 hash_set
<tree
, true> pset
;
938 /* We already called reshape_init in implicit_conversion. */
940 /* The conversions within the init-list aren't affected by the enclosing
941 context; they're always simple copy-initialization. */
942 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
944 /* For designated initializers, verify that each initializer is convertible
945 to corresponding TREE_TYPE (ce->index) and mark those FIELD_DECLs as
946 visited. In the following loop then ignore already visited
948 if (CONSTRUCTOR_IS_DESIGNATED_INIT (ctor
))
951 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor
), i
, idx
, val
)
953 if (idx
&& TREE_CODE (idx
) == FIELD_DECL
)
955 tree ftype
= TREE_TYPE (idx
);
958 if (TREE_CODE (ftype
) == ARRAY_TYPE
959 && TREE_CODE (val
) == CONSTRUCTOR
)
960 ok
= can_convert_array (ftype
, val
, flags
, complain
);
962 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
967 /* For unions, there should be just one initializer. */
968 if (TREE_CODE (type
) == UNION_TYPE
)
981 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
983 tree ftype
= TREE_TYPE (field
);
987 if (!pset
.is_empty () && field_in_pset (pset
, field
))
989 if (i
< CONSTRUCTOR_NELTS (ctor
))
991 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
994 else if (DECL_INITIAL (field
))
995 val
= get_nsdmi (field
, /*ctor*/false, complain
);
996 else if (TYPE_REF_P (ftype
))
997 /* Value-initialization of reference is ill-formed. */
1001 if (empty_ctor
== NULL_TREE
)
1002 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
1006 if (TREE_CODE (ftype
) == ARRAY_TYPE
1007 && TREE_CODE (val
) == CONSTRUCTOR
)
1008 ok
= can_convert_array (ftype
, val
, flags
, complain
);
1010 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
1016 if (TREE_CODE (type
) == UNION_TYPE
)
1020 if (i
< CONSTRUCTOR_NELTS (ctor
))
1023 c
= alloc_conversion (ck_aggr
);
1026 c
->user_conv_p
= true;
1027 c
->check_narrowing
= true;
1032 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
1033 array type, if such a conversion is possible. */
1036 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
1039 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1040 tree elttype
= TREE_TYPE (type
);
1045 enum conversion_rank rank
= cr_exact
;
1047 /* We might need to propagate the size from the element to the array. */
1048 complete_type (type
);
1050 if (TYPE_DOMAIN (type
)
1051 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
1053 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
1058 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1060 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1063 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1064 false, flags
, complain
);
1068 if (sub
->rank
> rank
)
1070 if (sub
->user_conv_p
)
1076 c
= alloc_conversion (ck_aggr
);
1079 c
->user_conv_p
= user
;
1085 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1086 complex type, if such a conversion is possible. */
1089 build_complex_conv (tree type
, tree ctor
, int flags
,
1090 tsubst_flags_t complain
)
1093 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1094 tree elttype
= TREE_TYPE (type
);
1099 enum conversion_rank rank
= cr_exact
;
1104 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1106 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1109 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1110 false, flags
, complain
);
1114 if (sub
->rank
> rank
)
1116 if (sub
->user_conv_p
)
1122 c
= alloc_conversion (ck_aggr
);
1125 c
->user_conv_p
= user
;
1131 /* Build a representation of the identity conversion from EXPR to
1132 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1135 build_identity_conv (tree type
, tree expr
)
1139 c
= alloc_conversion (ck_identity
);
1146 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1147 were multiple user-defined conversions to accomplish the job.
1148 Build a conversion that indicates that ambiguity. */
1151 build_ambiguous_conv (tree type
, tree expr
)
1155 c
= alloc_conversion (ck_ambig
);
1163 strip_top_quals (tree t
)
1165 if (TREE_CODE (t
) == ARRAY_TYPE
)
1167 return cp_build_qualified_type (t
, 0);
1170 /* Returns the standard conversion path (see [conv]) from type FROM to type
1171 TO, if any. For proper handling of null pointer constants, you must
1172 also pass the expression EXPR to convert from. If C_CAST_P is true,
1173 this conversion is coming from a C-style cast. */
1176 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1177 int flags
, tsubst_flags_t complain
)
1179 enum tree_code fcode
, tcode
;
1181 bool fromref
= false;
1184 to
= non_reference (to
);
1185 if (TYPE_REF_P (from
))
1188 from
= TREE_TYPE (from
);
1191 to
= strip_top_quals (to
);
1192 from
= strip_top_quals (from
);
1194 if (expr
&& type_unknown_p (expr
))
1196 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1198 tsubst_flags_t tflags
= tf_conv
;
1199 expr
= instantiate_type (to
, expr
, tflags
);
1200 if (expr
== error_mark_node
)
1202 from
= TREE_TYPE (expr
);
1204 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1206 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1207 expr
= resolve_nondeduced_context (expr
, complain
);
1208 from
= TREE_TYPE (expr
);
1212 fcode
= TREE_CODE (from
);
1213 tcode
= TREE_CODE (to
);
1215 conv
= build_identity_conv (from
, expr
);
1216 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1218 from
= type_decays_to (from
);
1219 fcode
= TREE_CODE (from
);
1220 /* Tell convert_like_real that we're using the address. */
1221 conv
->rvaluedness_matches_p
= true;
1222 conv
= build_conv (ck_lvalue
, from
, conv
);
1224 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1225 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1226 express the copy constructor call required by copy-initialization. */
1227 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1232 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1235 from
= strip_top_quals (bitfield_type
);
1236 fcode
= TREE_CODE (from
);
1239 conv
= build_conv (ck_rvalue
, from
, conv
);
1240 if (flags
& LOOKUP_PREFER_RVALUE
)
1241 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1242 conv
->rvaluedness_matches_p
= true;
1245 /* Allow conversion between `__complex__' data types. */
1246 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1248 /* The standard conversion sequence to convert FROM to TO is
1249 the standard conversion sequence to perform componentwise
1251 conversion
*part_conv
= standard_conversion
1252 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1257 conv
= build_conv (part_conv
->kind
, to
, conv
);
1258 conv
->rank
= part_conv
->rank
;
1266 if (same_type_p (from
, to
))
1268 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1269 conv
->type
= qualified_to
;
1274 A null pointer constant can be converted to a pointer type; ... A
1275 null pointer constant of integral type can be converted to an
1276 rvalue of type std::nullptr_t. */
1277 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1278 || NULLPTR_TYPE_P (to
))
1279 && ((expr
&& null_ptr_cst_p (expr
))
1280 || NULLPTR_TYPE_P (from
)))
1281 conv
= build_conv (ck_std
, to
, conv
);
1282 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1283 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1285 /* For backwards brain damage compatibility, allow interconversion of
1286 pointers and integers with a pedwarn. */
1287 conv
= build_conv (ck_std
, to
, conv
);
1290 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1292 /* For backwards brain damage compatibility, allow interconversion of
1293 enums and integers with a pedwarn. */
1294 conv
= build_conv (ck_std
, to
, conv
);
1297 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1298 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1303 if (tcode
== POINTER_TYPE
)
1305 to_pointee
= TREE_TYPE (to
);
1306 from_pointee
= TREE_TYPE (from
);
1308 /* Since this is the target of a pointer, it can't have function
1309 qualifiers, so any TYPE_QUALS must be for attributes const or
1310 noreturn. Strip them. */
1311 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1312 && TYPE_QUALS (to_pointee
))
1313 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1314 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1315 && TYPE_QUALS (from_pointee
))
1316 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1320 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1321 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1324 if (tcode
== POINTER_TYPE
1325 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1328 else if (VOID_TYPE_P (to_pointee
)
1329 && !TYPE_PTRDATAMEM_P (from
)
1330 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1332 tree nfrom
= TREE_TYPE (from
);
1333 /* Don't try to apply restrict to void. */
1334 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1335 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1336 from
= build_pointer_type (from_pointee
);
1337 conv
= build_conv (ck_ptr
, from
, conv
);
1339 else if (TYPE_PTRDATAMEM_P (from
))
1341 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1342 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1344 if (same_type_p (fbase
, tbase
))
1345 /* No base conversion needed. */;
1346 else if (DERIVED_FROM_P (fbase
, tbase
)
1347 && (same_type_ignoring_top_level_qualifiers_p
1348 (from_pointee
, to_pointee
)))
1350 from
= build_ptrmem_type (tbase
, from_pointee
);
1351 conv
= build_conv (ck_pmem
, from
, conv
);
1356 else if (CLASS_TYPE_P (from_pointee
)
1357 && CLASS_TYPE_P (to_pointee
)
1360 An rvalue of type "pointer to cv D," where D is a
1361 class type, can be converted to an rvalue of type
1362 "pointer to cv B," where B is a base class (clause
1363 _class.derived_) of D. If B is an inaccessible
1364 (clause _class.access_) or ambiguous
1365 (_class.member.lookup_) base class of D, a program
1366 that necessitates this conversion is ill-formed.
1367 Therefore, we use DERIVED_FROM_P, and do not check
1368 access or uniqueness. */
1369 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1372 = cp_build_qualified_type (to_pointee
,
1373 cp_type_quals (from_pointee
));
1374 from
= build_pointer_type (from_pointee
);
1375 conv
= build_conv (ck_ptr
, from
, conv
);
1376 conv
->base_p
= true;
1379 if (same_type_p (from
, to
))
1381 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1382 /* In a C-style cast, we ignore CV-qualification because we
1383 are allowed to perform a static_cast followed by a
1385 conv
= build_conv (ck_qual
, to
, conv
);
1386 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1387 conv
= build_conv (ck_qual
, to
, conv
);
1388 else if (expr
&& string_conv_p (to
, expr
, 0))
1389 /* converting from string constant to char *. */
1390 conv
= build_conv (ck_qual
, to
, conv
);
1391 else if (fnptr_conv_p (to
, from
))
1392 conv
= build_conv (ck_fnptr
, to
, conv
);
1393 /* Allow conversions among compatible ObjC pointer types (base
1394 conversions have been already handled above). */
1395 else if (c_dialect_objc ()
1396 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1397 conv
= build_conv (ck_ptr
, to
, conv
);
1398 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1400 conv
= build_conv (ck_ptr
, to
, conv
);
1408 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1410 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1411 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1412 tree fbase
= class_of_this_parm (fromfn
);
1413 tree tbase
= class_of_this_parm (tofn
);
1415 if (!DERIVED_FROM_P (fbase
, tbase
))
1418 tree fstat
= static_fn_type (fromfn
);
1419 tree tstat
= static_fn_type (tofn
);
1420 if (same_type_p (tstat
, fstat
)
1421 || fnptr_conv_p (tstat
, fstat
))
1426 if (!same_type_p (fbase
, tbase
))
1428 from
= build_memfn_type (fstat
,
1430 cp_type_quals (tbase
),
1431 type_memfn_rqual (tofn
));
1432 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1433 conv
= build_conv (ck_pmem
, from
, conv
);
1434 conv
->base_p
= true;
1436 if (fnptr_conv_p (tstat
, fstat
))
1437 conv
= build_conv (ck_fnptr
, to
, conv
);
1439 else if (tcode
== BOOLEAN_TYPE
)
1443 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1444 to member type can be converted to a prvalue of type bool. ...
1445 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1446 std::nullptr_t can be converted to a prvalue of type bool; */
1447 if (ARITHMETIC_TYPE_P (from
)
1448 || UNSCOPED_ENUM_P (from
)
1449 || fcode
== POINTER_TYPE
1450 || TYPE_PTRMEM_P (from
)
1451 || NULLPTR_TYPE_P (from
))
1453 conv
= build_conv (ck_std
, to
, conv
);
1454 if (fcode
== POINTER_TYPE
1455 || TYPE_PTRDATAMEM_P (from
)
1456 || (TYPE_PTRMEMFUNC_P (from
)
1457 && conv
->rank
< cr_pbool
)
1458 || NULLPTR_TYPE_P (from
))
1459 conv
->rank
= cr_pbool
;
1460 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1462 if (flags
& LOOKUP_NO_NARROWING
)
1463 conv
->check_narrowing
= true;
1469 /* We don't check for ENUMERAL_TYPE here because there are no standard
1470 conversions to enum type. */
1471 /* As an extension, allow conversion to complex type. */
1472 else if (ARITHMETIC_TYPE_P (to
))
1474 if (! (INTEGRAL_CODE_P (fcode
)
1475 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1476 || SCOPED_ENUM_P (from
))
1479 /* If we're parsing an enum with no fixed underlying type, we're
1480 dealing with an incomplete type, which renders the conversion
1482 if (!COMPLETE_TYPE_P (from
))
1485 conv
= build_conv (ck_std
, to
, conv
);
1487 /* Give this a better rank if it's a promotion. */
1488 if (same_type_p (to
, type_promotes_to (from
))
1489 && next_conversion (conv
)->rank
<= cr_promotion
)
1490 conv
->rank
= cr_promotion
;
1492 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1493 && vector_types_convertible_p (from
, to
, false))
1494 return build_conv (ck_std
, to
, conv
);
1495 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1496 && is_properly_derived_from (from
, to
))
1498 if (conv
->kind
== ck_rvalue
)
1499 conv
= next_conversion (conv
);
1500 conv
= build_conv (ck_base
, to
, conv
);
1501 /* The derived-to-base conversion indicates the initialization
1502 of a parameter with base type from an object of a derived
1503 type. A temporary object is created to hold the result of
1504 the conversion unless we're binding directly to a reference. */
1505 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1506 if (flags
& LOOKUP_PREFER_RVALUE
)
1507 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1508 conv
->rvaluedness_matches_p
= true;
1513 if (flags
& LOOKUP_NO_NARROWING
)
1514 conv
->check_narrowing
= true;
1519 /* Returns nonzero if T1 is reference-related to T2. */
1522 reference_related_p (tree t1
, tree t2
)
1524 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1527 t1
= TYPE_MAIN_VARIANT (t1
);
1528 t2
= TYPE_MAIN_VARIANT (t2
);
1532 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1533 to "cv2 T2" if T1 is similar to T2, or T1 is a base class of T2. */
1534 return (similar_type_p (t1
, t2
)
1535 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1536 && DERIVED_FROM_P (t1
, t2
)));
1539 /* Returns nonzero if T1 is reference-compatible with T2. */
1542 reference_compatible_p (tree t1
, tree t2
)
1546 "cv1 T1" is reference compatible with "cv2 T2" if
1547 a prvalue of type "pointer to cv2 T2" can be converted to the type
1548 "pointer to cv1 T1" via a standard conversion sequence. */
1549 tree ptype1
= build_pointer_type (t1
);
1550 tree ptype2
= build_pointer_type (t2
);
1551 conversion
*conv
= standard_conversion (ptype1
, ptype2
, NULL_TREE
,
1552 /*c_cast_p=*/false, 0, tf_none
);
1553 if (!conv
|| conv
->bad_p
)
1558 /* A reference of the indicated TYPE is being bound directly to the
1559 expression represented by the implicit conversion sequence CONV.
1560 Return a conversion sequence for this binding. */
1563 direct_reference_binding (tree type
, conversion
*conv
)
1567 gcc_assert (TYPE_REF_P (type
));
1568 gcc_assert (!TYPE_REF_P (conv
->type
));
1570 t
= TREE_TYPE (type
);
1572 if (conv
->kind
== ck_identity
)
1573 /* Mark the identity conv as to not decay to rvalue. */
1574 conv
->rvaluedness_matches_p
= true;
1578 When a parameter of reference type binds directly
1579 (_dcl.init.ref_) to an argument expression, the implicit
1580 conversion sequence is the identity conversion, unless the
1581 argument expression has a type that is a derived class of the
1582 parameter type, in which case the implicit conversion sequence is
1583 a derived-to-base Conversion.
1585 If the parameter binds directly to the result of applying a
1586 conversion function to the argument expression, the implicit
1587 conversion sequence is a user-defined conversion sequence
1588 (_over.ics.user_), with the second standard conversion sequence
1589 either an identity conversion or, if the conversion function
1590 returns an entity of a type that is a derived class of the
1591 parameter type, a derived-to-base conversion. */
1592 if (is_properly_derived_from (conv
->type
, t
))
1594 /* Represent the derived-to-base conversion. */
1595 conv
= build_conv (ck_base
, t
, conv
);
1596 /* We will actually be binding to the base-class subobject in
1597 the derived class, so we mark this conversion appropriately.
1598 That way, convert_like knows not to generate a temporary. */
1599 conv
->need_temporary_p
= false;
1602 return build_conv (ck_ref_bind
, type
, conv
);
1605 /* Returns the conversion path from type FROM to reference type TO for
1606 purposes of reference binding. For lvalue binding, either pass a
1607 reference type to FROM or an lvalue expression to EXPR. If the
1608 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1609 the conversion returned. If C_CAST_P is true, this
1610 conversion is coming from a C-style cast. */
1613 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1614 tsubst_flags_t complain
)
1616 conversion
*conv
= NULL
;
1617 tree to
= TREE_TYPE (rto
);
1622 cp_lvalue_kind gl_kind
;
1625 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1627 expr
= instantiate_type (to
, expr
, tf_none
);
1628 if (expr
== error_mark_node
)
1630 from
= TREE_TYPE (expr
);
1633 bool copy_list_init
= false;
1634 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1636 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1637 /* DR 1288: Otherwise, if the initializer list has a single element
1638 of type E and ... [T's] referenced type is reference-related to E,
1639 the object or reference is initialized from that element... */
1640 if (CONSTRUCTOR_NELTS (expr
) == 1)
1642 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1643 if (error_operand_p (elt
))
1645 tree etype
= TREE_TYPE (elt
);
1646 if (reference_related_p (to
, etype
))
1653 /* Otherwise, if T is a reference type, a prvalue temporary of the type
1654 referenced by T is copy-list-initialized, and the reference is bound
1655 to that temporary. */
1656 copy_list_init
= true;
1660 if (TYPE_REF_P (from
))
1662 from
= TREE_TYPE (from
);
1663 if (!TYPE_REF_IS_RVALUE (rfrom
)
1664 || TREE_CODE (from
) == FUNCTION_TYPE
)
1665 gl_kind
= clk_ordinary
;
1667 gl_kind
= clk_rvalueref
;
1670 gl_kind
= lvalue_kind (expr
);
1671 else if (CLASS_TYPE_P (from
)
1672 || TREE_CODE (from
) == ARRAY_TYPE
)
1673 gl_kind
= clk_class
;
1677 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1678 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1679 && (gl_kind
& clk_class
))
1682 /* Same mask as real_lvalue_p. */
1683 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1686 if ((gl_kind
& clk_bitfield
) != 0)
1687 tfrom
= unlowered_expr_type (expr
);
1689 /* Figure out whether or not the types are reference-related and
1690 reference compatible. We have to do this after stripping
1691 references from FROM. */
1692 related_p
= reference_related_p (to
, tfrom
);
1693 /* If this is a C cast, first convert to an appropriately qualified
1694 type, so that we can later do a const_cast to the desired type. */
1695 if (related_p
&& c_cast_p
1696 && !at_least_as_qualified_p (to
, tfrom
))
1697 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1698 compatible_p
= reference_compatible_p (to
, tfrom
);
1700 /* Directly bind reference when target expression's type is compatible with
1701 the reference and expression is an lvalue. In DR391, the wording in
1702 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1703 const and rvalue references to rvalues of compatible class type.
1704 We should also do direct bindings for non-class xvalues. */
1705 if ((related_p
|| compatible_p
) && gl_kind
)
1709 If the initializer expression
1711 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1712 is reference-compatible with "cv2 T2,"
1714 the reference is bound directly to the initializer expression
1718 If the initializer expression is an rvalue, with T2 a class type,
1719 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1720 is bound to the object represented by the rvalue or to a sub-object
1721 within that object. */
1723 conv
= build_identity_conv (tfrom
, expr
);
1724 conv
= direct_reference_binding (rto
, conv
);
1726 if (TYPE_REF_P (rfrom
))
1727 /* Handle rvalue reference to function properly. */
1728 conv
->rvaluedness_matches_p
1729 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1731 conv
->rvaluedness_matches_p
1732 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1734 if ((gl_kind
& clk_bitfield
) != 0
1735 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1736 /* For the purposes of overload resolution, we ignore the fact
1737 this expression is a bitfield or packed field. (In particular,
1738 [over.ics.ref] says specifically that a function with a
1739 non-const reference parameter is viable even if the
1740 argument is a bitfield.)
1742 However, when we actually call the function we must create
1743 a temporary to which to bind the reference. If the
1744 reference is volatile, or isn't const, then we cannot make
1745 a temporary, so we just issue an error when the conversion
1747 conv
->need_temporary_p
= true;
1749 /* Don't allow binding of lvalues (other than function lvalues) to
1750 rvalue references. */
1751 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1752 && TREE_CODE (to
) != FUNCTION_TYPE
)
1755 /* Nor the reverse. */
1756 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1757 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1758 || (flags
& LOOKUP_NO_RVAL_BIND
))
1759 && TREE_CODE (to
) != FUNCTION_TYPE
)
1767 /* [class.conv.fct] A conversion function is never used to convert a
1768 (possibly cv-qualified) object to the (possibly cv-qualified) same
1769 object type (or a reference to it), to a (possibly cv-qualified) base
1770 class of that type (or a reference to it).... */
1771 else if (CLASS_TYPE_P (from
) && !related_p
1772 && !(flags
& LOOKUP_NO_CONVERSION
))
1776 If the initializer expression
1778 -- has a class type (i.e., T2 is a class type) can be
1779 implicitly converted to an lvalue of type "cv3 T3," where
1780 "cv1 T1" is reference-compatible with "cv3 T3". (this
1781 conversion is selected by enumerating the applicable
1782 conversion functions (_over.match.ref_) and choosing the
1783 best one through overload resolution. (_over.match_).
1785 the reference is bound to the lvalue result of the conversion
1786 in the second case. */
1787 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1790 return cand
->second_conv
;
1793 /* From this point on, we conceptually need temporaries, even if we
1794 elide them. Only the cases above are "direct bindings". */
1795 if (flags
& LOOKUP_NO_TEMP_BIND
)
1800 When a parameter of reference type is not bound directly to an
1801 argument expression, the conversion sequence is the one required
1802 to convert the argument expression to the underlying type of the
1803 reference according to _over.best.ics_. Conceptually, this
1804 conversion sequence corresponds to copy-initializing a temporary
1805 of the underlying type with the argument expression. Any
1806 difference in top-level cv-qualification is subsumed by the
1807 initialization itself and does not constitute a conversion. */
1811 Otherwise, the reference shall be an lvalue reference to a
1812 non-volatile const type, or the reference shall be an rvalue
1815 We try below to treat this as a bad conversion to improve diagnostics,
1816 but if TO is an incomplete class, we need to reject this conversion
1817 now to avoid unnecessary instantiation. */
1818 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1819 && !COMPLETE_TYPE_P (to
))
1822 /* We're generating a temporary now, but don't bind any more in the
1823 conversion (specifically, don't slice the temporary returned by a
1824 conversion operator). */
1825 flags
|= LOOKUP_NO_TEMP_BIND
;
1827 /* Core issue 899: When [copy-]initializing a temporary to be bound
1828 to the first parameter of a copy constructor (12.8) called with
1829 a single argument in the context of direct-initialization,
1830 explicit conversion functions are also considered.
1832 So don't set LOOKUP_ONLYCONVERTING in that case. */
1833 if (!(flags
& LOOKUP_COPY_PARM
))
1834 flags
|= LOOKUP_ONLYCONVERTING
;
1837 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1842 if (conv
->user_conv_p
)
1845 /* Remember this was copy-list-initialization. */
1846 conv
->need_temporary_p
= true;
1848 /* If initializing the temporary used a conversion function,
1849 recalculate the second conversion sequence. */
1850 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1851 if (t
->kind
== ck_user
1852 && DECL_CONV_FN_P (t
->cand
->fn
))
1854 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1855 /* A prvalue of non-class type is cv-unqualified. */
1856 if (!TYPE_REF_P (ftype
) && !CLASS_TYPE_P (ftype
))
1857 ftype
= cv_unqualified (ftype
);
1858 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1859 conversion
*new_second
1860 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1864 return merge_conversion_sequences (t
, new_second
);
1868 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1869 /* This reference binding, unlike those above, requires the
1870 creation of a temporary. */
1871 conv
->need_temporary_p
= true;
1872 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1876 Otherwise, the reference shall be an lvalue reference to a
1877 non-volatile const type, or the reference shall be an rvalue
1879 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1884 Otherwise, a temporary of type "cv1 T1" is created and
1885 initialized from the initializer expression using the rules for a
1886 non-reference copy initialization. If T1 is reference-related to
1887 T2, cv1 must be the same cv-qualification as, or greater
1888 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1889 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1895 /* Returns the implicit conversion sequence (see [over.ics]) from type
1896 FROM to type TO. The optional expression EXPR may affect the
1897 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1898 true, this conversion is coming from a C-style cast. */
1901 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1902 int flags
, tsubst_flags_t complain
)
1906 if (from
== error_mark_node
|| to
== error_mark_node
1907 || expr
== error_mark_node
)
1910 /* Other flags only apply to the primary function in overload
1911 resolution, or after we've chosen one. */
1912 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1913 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1914 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1916 /* FIXME: actually we don't want warnings either, but we can't just
1917 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1918 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1919 We really ought not to issue that warning until we've committed
1920 to that conversion. */
1921 complain
&= ~tf_error
;
1923 /* Call reshape_init early to remove redundant braces. */
1924 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1925 && CLASS_TYPE_P (to
)
1926 && COMPLETE_TYPE_P (complete_type (to
))
1927 && !CLASSTYPE_NON_AGGREGATE (to
))
1929 expr
= reshape_init (to
, expr
, complain
);
1930 if (expr
== error_mark_node
)
1932 from
= TREE_TYPE (expr
);
1935 if (TYPE_REF_P (to
))
1936 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1938 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1943 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1945 if (is_std_init_list (to
) && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1946 return build_list_conv (to
, expr
, flags
, complain
);
1948 /* As an extension, allow list-initialization of _Complex. */
1949 if (TREE_CODE (to
) == COMPLEX_TYPE
1950 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1952 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1957 /* Allow conversion from an initializer-list with one element to a
1959 if (SCALAR_TYPE_P (to
))
1961 int nelts
= CONSTRUCTOR_NELTS (expr
);
1965 elt
= build_value_init (to
, tf_none
);
1966 else if (nelts
== 1 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1967 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1969 elt
= error_mark_node
;
1971 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1972 c_cast_p
, flags
, complain
);
1975 conv
->check_narrowing
= true;
1976 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1977 /* Too many levels of braces, i.e. '{{1}}'. */
1982 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1983 return build_array_conv (to
, expr
, flags
, complain
);
1986 if (expr
!= NULL_TREE
1987 && (MAYBE_CLASS_TYPE_P (from
)
1988 || MAYBE_CLASS_TYPE_P (to
))
1989 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1991 struct z_candidate
*cand
;
1993 if (CLASS_TYPE_P (to
)
1994 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1995 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1996 return build_aggr_conv (to
, expr
, flags
, complain
);
1998 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
2001 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
2002 && CONSTRUCTOR_NELTS (expr
) == 1
2003 && !is_list_ctor (cand
->fn
))
2005 /* "If C is not an initializer-list constructor and the
2006 initializer list has a single element of type cv U, where U is
2007 X or a class derived from X, the implicit conversion sequence
2008 has Exact Match rank if U is X, or Conversion rank if U is
2010 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
2011 tree elttype
= TREE_TYPE (elt
);
2012 if (reference_related_p (to
, elttype
))
2013 return implicit_conversion (to
, elttype
, elt
,
2014 c_cast_p
, flags
, complain
);
2016 conv
= cand
->second_conv
;
2019 /* We used to try to bind a reference to a temporary here, but that
2020 is now handled after the recursive call to this function at the end
2021 of reference_binding. */
2028 /* Like implicit_conversion, but return NULL if the conversion is bad.
2030 This is not static so that check_non_deducible_conversion can call it within
2031 add_template_candidate_real as part of overload resolution; it should not be
2032 called outside of overload resolution. */
2035 good_conversion (tree to
, tree from
, tree expr
,
2036 int flags
, tsubst_flags_t complain
)
2038 conversion
*c
= implicit_conversion (to
, from
, expr
, /*cast*/false,
2045 /* Add a new entry to the list of candidates. Used by the add_*_candidate
2046 functions. ARGS will not be changed until a single candidate is
2049 static struct z_candidate
*
2050 add_candidate (struct z_candidate
**candidates
,
2051 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
2052 size_t num_convs
, conversion
**convs
,
2053 tree access_path
, tree conversion_path
,
2054 int viable
, struct rejection_reason
*reason
,
2057 struct z_candidate
*cand
= (struct z_candidate
*)
2058 conversion_obstack_alloc (sizeof (struct z_candidate
));
2061 cand
->first_arg
= first_arg
;
2063 cand
->convs
= convs
;
2064 cand
->num_convs
= num_convs
;
2065 cand
->access_path
= access_path
;
2066 cand
->conversion_path
= conversion_path
;
2067 cand
->viable
= viable
;
2068 cand
->reason
= reason
;
2069 cand
->next
= *candidates
;
2070 cand
->flags
= flags
;
2076 /* Return the number of remaining arguments in the parameter list
2077 beginning with ARG. */
2080 remaining_arguments (tree arg
)
2084 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
2085 arg
= TREE_CHAIN (arg
))
2091 /* [over.match.copy]: When initializing a temporary object (12.2) to be bound
2092 to the first parameter of a constructor where the parameter is of type
2093 "reference to possibly cv-qualified T" and the constructor is called with a
2094 single argument in the context of direct-initialization of an object of type
2095 "cv2 T", explicit conversion functions are also considered.
2097 So set LOOKUP_COPY_PARM to let reference_binding know that
2098 it's being called in that context. */
2101 conv_flags (int i
, int nargs
, tree fn
, tree arg
, int flags
)
2105 if (i
== 0 && nargs
== 1 && DECL_CONSTRUCTOR_P (fn
)
2106 && (t
= FUNCTION_FIRST_USER_PARMTYPE (fn
))
2107 && (same_type_ignoring_top_level_qualifiers_p
2108 (non_reference (TREE_VALUE (t
)), DECL_CONTEXT (fn
))))
2110 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2111 lflags
|= LOOKUP_COPY_PARM
;
2112 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2113 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2114 lflags
|= LOOKUP_NO_CONVERSION
;
2117 lflags
|= LOOKUP_ONLYCONVERTING
;
2122 /* Create an overload candidate for the function or method FN called
2123 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
2124 FLAGS is passed on to implicit_conversion.
2126 This does not change ARGS.
2128 CTYPE, if non-NULL, is the type we want to pretend this function
2129 comes from for purposes of overload resolution. */
2131 static struct z_candidate
*
2132 add_function_candidate (struct z_candidate
**candidates
,
2133 tree fn
, tree ctype
, tree first_arg
,
2134 const vec
<tree
, va_gc
> *args
, tree access_path
,
2135 tree conversion_path
, int flags
,
2137 tsubst_flags_t complain
)
2139 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2142 tree orig_first_arg
= first_arg
;
2145 struct rejection_reason
*reason
= NULL
;
2147 /* At this point we should not see any functions which haven't been
2148 explicitly declared, except for friend functions which will have
2149 been found using argument dependent lookup. */
2150 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2152 /* The `this', `in_chrg' and VTT arguments to constructors are not
2153 considered in overload resolution. */
2154 if (DECL_CONSTRUCTOR_P (fn
))
2156 if (ctor_omit_inherited_parms (fn
))
2157 /* Bring back parameters omitted from an inherited ctor. */
2158 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2160 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2161 skip
= num_artificial_parms_for (fn
);
2162 if (skip
> 0 && first_arg
!= NULL_TREE
)
2165 first_arg
= NULL_TREE
;
2171 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2173 convs
= alloc_conversions (len
);
2175 /* 13.3.2 - Viable functions [over.match.viable]
2176 First, to be a viable function, a candidate function shall have enough
2177 parameters to agree in number with the arguments in the list.
2179 We need to check this first; otherwise, checking the ICSes might cause
2180 us to produce an ill-formed template instantiation. */
2182 parmnode
= parmlist
;
2183 for (i
= 0; i
< len
; ++i
)
2185 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2187 parmnode
= TREE_CHAIN (parmnode
);
2190 if ((i
< len
&& parmnode
)
2191 || !sufficient_parms_p (parmnode
))
2193 int remaining
= remaining_arguments (parmnode
);
2195 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2198 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2199 parameter of type "reference to cv C" (including such a constructor
2200 instantiated from a template) is excluded from the set of candidate
2201 functions when used to construct an object of type D with an argument list
2202 containing a single argument if C is reference-related to D. */
2203 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2204 && flag_new_inheriting_ctors
2205 && DECL_INHERITED_CTOR (fn
))
2207 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2208 tree dtype
= DECL_CONTEXT (fn
);
2209 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2210 if (reference_related_p (ptype
, dtype
)
2211 && reference_related_p (btype
, ptype
))
2214 reason
= inherited_ctor_rejection ();
2218 /* Second, for a function to be viable, its constraints must be
2220 if (flag_concepts
&& viable
2221 && !constraints_satisfied_p (fn
))
2223 reason
= constraint_failure (fn
);
2227 /* When looking for a function from a subobject from an implicit
2228 copy/move constructor/operator=, don't consider anything that takes (a
2229 reference to) an unrelated type. See c++/44909 and core 1092. */
2230 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2232 if (DECL_CONSTRUCTOR_P (fn
))
2234 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2235 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2241 parmnode
= chain_index (i
-1, parmlist
);
2242 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2247 /* This only applies at the top level. */
2248 flags
&= ~LOOKUP_DEFAULTED
;
2254 /* Third, for F to be a viable function, there shall exist for each
2255 argument an implicit conversion sequence that converts that argument
2256 to the corresponding parameter of F. */
2258 parmnode
= parmlist
;
2260 for (i
= 0; i
< len
; ++i
)
2262 tree argtype
, to_type
;
2267 if (parmnode
== void_list_node
)
2272 /* Already set during deduction. */
2273 parmnode
= TREE_CHAIN (parmnode
);
2277 if (i
== 0 && first_arg
!= NULL_TREE
)
2280 arg
= CONST_CAST_TREE (
2281 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2282 argtype
= lvalue_type (arg
);
2284 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2285 && ! DECL_CONSTRUCTOR_P (fn
));
2289 tree parmtype
= TREE_VALUE (parmnode
);
2291 parmnode
= TREE_CHAIN (parmnode
);
2293 /* The type of the implicit object parameter ('this') for
2294 overload resolution is not always the same as for the
2295 function itself; conversion functions are considered to
2296 be members of the class being converted, and functions
2297 introduced by a using-declaration are considered to be
2298 members of the class that uses them.
2300 Since build_over_call ignores the ICS for the `this'
2301 parameter, we can just change the parm type. */
2302 if (ctype
&& is_this
)
2304 parmtype
= cp_build_qualified_type
2305 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2306 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2308 /* If the function has a ref-qualifier, the implicit
2309 object parameter has reference type. */
2310 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2311 parmtype
= cp_build_reference_type (parmtype
, rv
);
2312 /* The special handling of 'this' conversions in compare_ics
2313 does not apply if there is a ref-qualifier. */
2318 parmtype
= build_pointer_type (parmtype
);
2319 /* We don't use build_this here because we don't want to
2320 capture the object argument until we've chosen a
2321 non-static member function. */
2322 arg
= build_address (arg
);
2323 argtype
= lvalue_type (arg
);
2327 int lflags
= conv_flags (i
, len
-skip
, fn
, arg
, flags
);
2329 t
= implicit_conversion (parmtype
, argtype
, arg
,
2330 /*c_cast_p=*/false, lflags
, complain
);
2335 t
= build_identity_conv (argtype
, arg
);
2336 t
->ellipsis_p
= true;
2347 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
,
2348 EXPR_LOCATION (arg
));
2355 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
,
2356 EXPR_LOCATION (arg
));
2362 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2363 access_path
, conversion_path
, viable
, reason
, flags
);
2366 /* Create an overload candidate for the conversion function FN which will
2367 be invoked for expression OBJ, producing a pointer-to-function which
2368 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2369 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2370 passed on to implicit_conversion.
2372 Actually, we don't really care about FN; we care about the type it
2373 converts to. There may be multiple conversion functions that will
2374 convert to that type, and we rely on build_user_type_conversion_1 to
2375 choose the best one; so when we create our candidate, we record the type
2376 instead of the function. */
2378 static struct z_candidate
*
2379 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2380 const vec
<tree
, va_gc
> *arglist
,
2381 tree access_path
, tree conversion_path
,
2382 tsubst_flags_t complain
)
2384 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2385 int i
, len
, viable
, flags
;
2386 tree parmlist
, parmnode
;
2388 struct rejection_reason
*reason
;
2390 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2391 parmlist
= TREE_TYPE (parmlist
);
2392 parmlist
= TYPE_ARG_TYPES (parmlist
);
2394 len
= vec_safe_length (arglist
) + 1;
2395 convs
= alloc_conversions (len
);
2396 parmnode
= parmlist
;
2398 flags
= LOOKUP_IMPLICIT
;
2401 /* Don't bother looking up the same type twice. */
2402 if (*candidates
&& (*candidates
)->fn
== totype
)
2405 for (i
= 0; i
< len
; ++i
)
2407 tree arg
, argtype
, convert_type
= NULL_TREE
;
2413 arg
= (*arglist
)[i
- 1];
2414 argtype
= lvalue_type (arg
);
2418 t
= build_identity_conv (argtype
, NULL_TREE
);
2419 t
= build_conv (ck_user
, totype
, t
);
2420 /* Leave the 'cand' field null; we'll figure out the conversion in
2421 convert_like_real if this candidate is chosen. */
2422 convert_type
= totype
;
2424 else if (parmnode
== void_list_node
)
2428 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2429 /*c_cast_p=*/false, flags
, complain
);
2430 convert_type
= TREE_VALUE (parmnode
);
2434 t
= build_identity_conv (argtype
, arg
);
2435 t
->ellipsis_p
= true;
2436 convert_type
= argtype
;
2446 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
,
2447 EXPR_LOCATION (arg
));
2454 parmnode
= TREE_CHAIN (parmnode
);
2458 || ! sufficient_parms_p (parmnode
))
2460 int remaining
= remaining_arguments (parmnode
);
2462 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2465 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2466 access_path
, conversion_path
, viable
, reason
, flags
);
2470 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2471 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2472 int flags
, tsubst_flags_t complain
)
2479 struct rejection_reason
*reason
= NULL
;
2484 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2485 convs
= alloc_conversions (num_convs
);
2487 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2488 conversion ops are allowed. We handle that here by just checking for
2489 boolean_type_node because other operators don't ask for it. COND_EXPR
2490 also does contextual conversion to bool for the first operand, but we
2491 handle that in build_conditional_expr, and type1 here is operand 2. */
2492 if (type1
!= boolean_type_node
)
2493 flags
|= LOOKUP_ONLYCONVERTING
;
2495 for (i
= 0; i
< 2; ++i
)
2500 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2501 /*c_cast_p=*/false, flags
, complain
);
2505 /* We need something for printing the candidate. */
2506 t
= build_identity_conv (types
[i
], NULL_TREE
);
2507 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2508 types
[i
], EXPR_LOCATION (args
[i
]));
2513 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2515 EXPR_LOCATION (args
[i
]));
2520 /* For COND_EXPR we rearranged the arguments; undo that now. */
2523 convs
[2] = convs
[1];
2524 convs
[1] = convs
[0];
2525 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2526 /*c_cast_p=*/false, flags
,
2533 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2535 EXPR_LOCATION (args
[2]));
2539 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2541 /*access_path=*/NULL_TREE
,
2542 /*conversion_path=*/NULL_TREE
,
2543 viable
, reason
, flags
);
2547 is_complete (tree t
)
2549 return COMPLETE_TYPE_P (complete_type (t
));
2552 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2555 promoted_arithmetic_type_p (tree type
)
2559 In this section, the term promoted integral type is used to refer
2560 to those integral types which are preserved by integral promotion
2561 (including e.g. int and long but excluding e.g. char).
2562 Similarly, the term promoted arithmetic type refers to promoted
2563 integral types plus floating types. */
2564 return ((CP_INTEGRAL_TYPE_P (type
)
2565 && same_type_p (type_promotes_to (type
), type
))
2566 || TREE_CODE (type
) == REAL_TYPE
);
2569 /* Create any builtin operator overload candidates for the operator in
2570 question given the converted operand types TYPE1 and TYPE2. The other
2571 args are passed through from add_builtin_candidates to
2572 build_builtin_candidate.
2574 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2575 If CODE is requires candidates operands of the same type of the kind
2576 of which TYPE1 and TYPE2 are, we add both candidates
2577 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2580 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2581 enum tree_code code2
, tree fnname
, tree type1
,
2582 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2583 tsubst_flags_t complain
)
2587 case POSTINCREMENT_EXPR
:
2588 case POSTDECREMENT_EXPR
:
2589 args
[1] = integer_zero_node
;
2590 type2
= integer_type_node
;
2599 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2600 and VQ is either volatile or empty, there exist candidate operator
2601 functions of the form
2602 VQ T& operator++(VQ T&);
2603 T operator++(VQ T&, int);
2604 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2605 type other than bool, and VQ is either volatile or empty, there exist
2606 candidate operator functions of the form
2607 VQ T& operator--(VQ T&);
2608 T operator--(VQ T&, int);
2609 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2610 complete object type, and VQ is either volatile or empty, there exist
2611 candidate operator functions of the form
2612 T*VQ& operator++(T*VQ&);
2613 T*VQ& operator--(T*VQ&);
2614 T* operator++(T*VQ&, int);
2615 T* operator--(T*VQ&, int); */
2617 case POSTDECREMENT_EXPR
:
2618 case PREDECREMENT_EXPR
:
2619 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2622 case POSTINCREMENT_EXPR
:
2623 case PREINCREMENT_EXPR
:
2624 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2626 type1
= build_reference_type (type1
);
2631 /* 7 For every cv-qualified or cv-unqualified object type T, there
2632 exist candidate operator functions of the form
2636 8 For every function type T, there exist candidate operator functions of
2638 T& operator*(T*); */
2641 if (TYPE_PTR_P (type1
)
2642 && (TYPE_PTROB_P (type1
)
2643 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2647 /* 9 For every type T, there exist candidate operator functions of the form
2650 10For every promoted arithmetic type T, there exist candidate operator
2651 functions of the form
2655 case UNARY_PLUS_EXPR
: /* unary + */
2656 if (TYPE_PTR_P (type1
))
2660 if (ARITHMETIC_TYPE_P (type1
))
2664 /* 11For every promoted integral type T, there exist candidate operator
2665 functions of the form
2669 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2673 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2674 is the same type as C2 or is a derived class of C2, T is a complete
2675 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2676 there exist candidate operator functions of the form
2677 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2678 where CV12 is the union of CV1 and CV2. */
2681 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2683 tree c1
= TREE_TYPE (type1
);
2684 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2686 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2687 && (TYPE_PTRMEMFUNC_P (type2
)
2688 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2693 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2694 didate operator functions of the form
2699 bool operator<(L, R);
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 where LR is the result of the usual arithmetic conversions between
2708 14For every pair of types T and I, where T is a cv-qualified or cv-
2709 unqualified complete object type and I is a promoted integral type,
2710 there exist candidate operator functions of the form
2711 T* operator+(T*, I);
2712 T& operator[](T*, I);
2713 T* operator-(T*, I);
2714 T* operator+(I, T*);
2715 T& operator[](I, T*);
2717 15For every T, where T is a pointer to complete object type, there exist
2718 candidate operator functions of the form112)
2719 ptrdiff_t operator-(T, T);
2721 16For every pointer or enumeration type T, there exist candidate operator
2722 functions of the form
2723 bool operator<(T, T);
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);
2730 17For every pointer to member type T, there exist candidate operator
2731 functions of the form
2732 bool operator==(T, T);
2733 bool operator!=(T, T); */
2736 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2738 if (TYPE_PTROB_P (type1
)
2739 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2741 type2
= ptrdiff_type_node
;
2746 case TRUNC_DIV_EXPR
:
2747 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2753 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2754 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2756 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2761 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2773 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2775 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2777 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2778 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2780 if (TYPE_PTR_P (type1
)
2781 && null_ptr_cst_p (args
[1]))
2786 if (null_ptr_cst_p (args
[0])
2787 && TYPE_PTR_P (type2
))
2795 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2799 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2801 type1
= ptrdiff_type_node
;
2804 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2806 type2
= ptrdiff_type_node
;
2811 /* 18For every pair of promoted integral types L and R, there exist candi-
2812 date operator functions of the form
2819 where LR is the result of the usual arithmetic conversions between
2822 case TRUNC_MOD_EXPR
:
2828 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2832 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2833 type, VQ is either volatile or empty, and R is a promoted arithmetic
2834 type, there exist candidate operator functions of the form
2835 VQ L& operator=(VQ L&, R);
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);
2841 20For every pair T, VQ), where T is any type and VQ is either volatile
2842 or empty, there exist candidate operator functions of the form
2843 T*VQ& operator=(T*VQ&, T*);
2845 21For every pair T, VQ), where T is a pointer to member type and VQ is
2846 either volatile or empty, there exist candidate operator functions of
2848 VQ T& operator=(VQ T&, T);
2850 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2851 unqualified complete object type, VQ is either volatile or empty, and
2852 I is a promoted integral type, there exist candidate operator func-
2854 T*VQ& operator+=(T*VQ&, I);
2855 T*VQ& operator-=(T*VQ&, I);
2857 23For every triple L, VQ, R), where L is an integral or enumeration
2858 type, VQ is either volatile or empty, and R is a promoted integral
2859 type, there exist candidate operator functions of the form
2861 VQ L& operator%=(VQ L&, R);
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); */
2873 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2875 type2
= ptrdiff_type_node
;
2880 case TRUNC_DIV_EXPR
:
2881 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2885 case TRUNC_MOD_EXPR
:
2891 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2896 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2898 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2899 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2900 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2901 || ((TYPE_PTRMEMFUNC_P (type1
)
2902 || TYPE_PTR_P (type1
))
2903 && null_ptr_cst_p (args
[1])))
2913 type1
= build_reference_type (type1
);
2919 For every pair of promoted arithmetic types L and R, there
2920 exist candidate operator functions of the form
2922 LR operator?(bool, L, R);
2924 where LR is the result of the usual arithmetic conversions
2925 between types L and R.
2927 For every type T, where T is a pointer or pointer-to-member
2928 type, there exist candidate operator functions of the form T
2929 operator?(bool, T, T); */
2931 if (promoted_arithmetic_type_p (type1
)
2932 && promoted_arithmetic_type_p (type2
))
2936 /* Otherwise, the types should be pointers. */
2937 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2940 /* We don't check that the two types are the same; the logic
2941 below will actually create two candidates; one in which both
2942 parameter types are TYPE1, and one in which both parameter
2948 if (ARITHMETIC_TYPE_P (type1
))
2956 /* Make sure we don't create builtin candidates with dependent types. */
2957 bool u1
= uses_template_parms (type1
);
2958 bool u2
= type2
? uses_template_parms (type2
) : false;
2961 /* Try to recover if one of the types is non-dependent. But if
2962 there's only one type, there's nothing we can do. */
2965 /* And we lose if both are dependent. */
2968 /* Or if they have different forms. */
2969 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2978 /* If we're dealing with two pointer types or two enumeral types,
2979 we need candidates for both of them. */
2980 if (type2
&& !same_type_p (type1
, type2
)
2981 && TREE_CODE (type1
) == TREE_CODE (type2
)
2982 && (TYPE_REF_P (type1
)
2983 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2984 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2985 || TYPE_PTRMEMFUNC_P (type1
)
2986 || MAYBE_CLASS_TYPE_P (type1
)
2987 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2989 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2991 tree cptype
= composite_pointer_type (type1
, type2
,
2996 if (cptype
!= error_mark_node
)
2998 build_builtin_candidate
2999 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
3005 build_builtin_candidate
3006 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
3007 build_builtin_candidate
3008 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
3012 build_builtin_candidate
3013 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
3017 type_decays_to (tree type
)
3019 if (TREE_CODE (type
) == ARRAY_TYPE
)
3020 return build_pointer_type (TREE_TYPE (type
));
3021 if (TREE_CODE (type
) == FUNCTION_TYPE
)
3022 return build_pointer_type (type
);
3026 /* There are three conditions of builtin candidates:
3028 1) bool-taking candidates. These are the same regardless of the input.
3029 2) pointer-pair taking candidates. These are generated for each type
3030 one of the input types converts to.
3031 3) arithmetic candidates. According to the standard, we should generate
3032 all of these, but I'm trying not to...
3034 Here we generate a superset of the possible candidates for this particular
3035 case. That is a subset of the full set the standard defines, plus some
3036 other cases which the standard disallows. add_builtin_candidate will
3037 filter out the invalid set. */
3040 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
3041 enum tree_code code2
, tree fnname
, tree
*args
,
3042 int flags
, tsubst_flags_t complain
)
3046 tree type
, argtypes
[3], t
;
3047 /* TYPES[i] is the set of possible builtin-operator parameter types
3048 we will consider for the Ith argument. */
3049 vec
<tree
, va_gc
> *types
[2];
3052 for (i
= 0; i
< 3; ++i
)
3055 argtypes
[i
] = unlowered_expr_type (args
[i
]);
3057 argtypes
[i
] = NULL_TREE
;
3062 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
3063 and VQ is either volatile or empty, there exist candidate operator
3064 functions of the form
3065 VQ T& operator++(VQ T&); */
3067 case POSTINCREMENT_EXPR
:
3068 case PREINCREMENT_EXPR
:
3069 case POSTDECREMENT_EXPR
:
3070 case PREDECREMENT_EXPR
:
3075 /* 24There also exist candidate operator functions of the form
3076 bool operator!(bool);
3077 bool operator&&(bool, bool);
3078 bool operator||(bool, bool); */
3080 case TRUTH_NOT_EXPR
:
3081 build_builtin_candidate
3082 (candidates
, fnname
, boolean_type_node
,
3083 NULL_TREE
, args
, argtypes
, flags
, complain
);
3086 case TRUTH_ORIF_EXPR
:
3087 case TRUTH_ANDIF_EXPR
:
3088 build_builtin_candidate
3089 (candidates
, fnname
, boolean_type_node
,
3090 boolean_type_node
, args
, argtypes
, flags
, complain
);
3112 types
[0] = make_tree_vector ();
3113 types
[1] = make_tree_vector ();
3115 for (i
= 0; i
< 2; ++i
)
3119 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
3123 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
3126 convs
= lookup_conversions (argtypes
[i
]);
3128 if (code
== COND_EXPR
)
3130 if (lvalue_p (args
[i
]))
3131 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3133 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3139 for (; convs
; convs
= TREE_CHAIN (convs
))
3141 type
= TREE_TYPE (convs
);
3144 && (!TYPE_REF_P (type
)
3145 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3148 if (code
== COND_EXPR
&& TYPE_REF_P (type
))
3149 vec_safe_push (types
[i
], type
);
3151 type
= non_reference (type
);
3152 if (i
!= 0 || ! ref1
)
3154 type
= cv_unqualified (type_decays_to (type
));
3155 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3156 vec_safe_push (types
[i
], type
);
3157 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3158 type
= type_promotes_to (type
);
3161 if (! vec_member (type
, types
[i
]))
3162 vec_safe_push (types
[i
], type
);
3167 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3168 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3169 type
= non_reference (argtypes
[i
]);
3170 if (i
!= 0 || ! ref1
)
3172 type
= cv_unqualified (type_decays_to (type
));
3173 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3174 vec_safe_push (types
[i
], type
);
3175 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3176 type
= type_promotes_to (type
);
3178 vec_safe_push (types
[i
], type
);
3182 /* Run through the possible parameter types of both arguments,
3183 creating candidates with those parameter types. */
3184 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3189 if (!types
[1]->is_empty ())
3190 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3191 add_builtin_candidate
3192 (candidates
, code
, code2
, fnname
, t
,
3193 u
, args
, argtypes
, flags
, complain
);
3195 add_builtin_candidate
3196 (candidates
, code
, code2
, fnname
, t
,
3197 NULL_TREE
, args
, argtypes
, flags
, complain
);
3200 release_tree_vector (types
[0]);
3201 release_tree_vector (types
[1]);
3205 /* If TMPL can be successfully instantiated as indicated by
3206 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3208 TMPL is the template. EXPLICIT_TARGS are any explicit template
3209 arguments. ARGLIST is the arguments provided at the call-site.
3210 This does not change ARGLIST. The RETURN_TYPE is the desired type
3211 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3212 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3213 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3215 static struct z_candidate
*
3216 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3217 tree ctype
, tree explicit_targs
, tree first_arg
,
3218 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3219 tree access_path
, tree conversion_path
,
3220 int flags
, tree obj
, unification_kind_t strict
,
3221 tsubst_flags_t complain
)
3223 int ntparms
= DECL_NTPARMS (tmpl
);
3224 tree targs
= make_tree_vec (ntparms
);
3225 unsigned int len
= vec_safe_length (arglist
);
3226 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3227 unsigned int skip_without_in_chrg
= 0;
3228 tree first_arg_without_in_chrg
= first_arg
;
3229 tree
*args_without_in_chrg
;
3230 unsigned int nargs_without_in_chrg
;
3231 unsigned int ia
, ix
;
3233 struct z_candidate
*cand
;
3235 struct rejection_reason
*reason
= NULL
;
3237 conversion
**convs
= NULL
;
3239 /* We don't do deduction on the in-charge parameter, the VTT
3240 parameter or 'this'. */
3241 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3243 if (first_arg_without_in_chrg
!= NULL_TREE
)
3244 first_arg_without_in_chrg
= NULL_TREE
;
3245 else if (return_type
&& strict
== DEDUCE_CALL
)
3246 /* We're deducing for a call to the result of a template conversion
3247 function, so the args don't contain 'this'; leave them alone. */;
3249 ++skip_without_in_chrg
;
3252 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3253 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3254 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3256 if (first_arg_without_in_chrg
!= NULL_TREE
)
3257 first_arg_without_in_chrg
= NULL_TREE
;
3259 ++skip_without_in_chrg
;
3262 if (len
< skip_without_in_chrg
)
3265 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3266 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3267 TREE_TYPE ((*arglist
)[0])))
3269 /* 12.8/6 says, "A declaration of a constructor for a class X is
3270 ill-formed if its first parameter is of type (optionally cv-qualified)
3271 X and either there are no other parameters or else all other
3272 parameters have default arguments. A member function template is never
3273 instantiated to produce such a constructor signature."
3275 So if we're trying to copy an object of the containing class, don't
3276 consider a template constructor that has a first parameter type that
3277 is just a template parameter, as we would deduce a signature that we
3278 would then reject in the code below. */
3279 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3281 firstparm
= TREE_VALUE (firstparm
);
3282 if (PACK_EXPANSION_P (firstparm
))
3283 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3284 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3286 gcc_assert (!explicit_targs
);
3287 reason
= invalid_copy_with_fn_template_rejection ();
3293 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3294 + (len
- skip_without_in_chrg
));
3295 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3297 if (first_arg_without_in_chrg
!= NULL_TREE
)
3299 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3302 for (ix
= skip_without_in_chrg
;
3303 vec_safe_iterate (arglist
, ix
, &arg
);
3306 args_without_in_chrg
[ia
] = arg
;
3309 gcc_assert (ia
== nargs_without_in_chrg
);
3311 errs
= errorcount
+sorrycount
;
3313 convs
= alloc_conversions (nargs
);
3314 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3315 args_without_in_chrg
,
3316 nargs_without_in_chrg
,
3317 return_type
, strict
, flags
, convs
,
3318 false, complain
& tf_decltype
);
3320 if (fn
== error_mark_node
)
3322 /* Don't repeat unification later if it already resulted in errors. */
3323 if (errorcount
+sorrycount
== errs
)
3324 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3325 targs
, args_without_in_chrg
,
3326 nargs_without_in_chrg
,
3327 return_type
, strict
, flags
);
3329 reason
= template_unification_error_rejection ();
3333 /* Now the explicit specifier might have been deduced; check if this
3334 declaration is explicit. If it is and we're ignoring non-converting
3335 constructors, don't add this function to the set of candidates. */
3336 if ((flags
& LOOKUP_ONLYCONVERTING
) && DECL_NONCONVERTING_P (fn
))
3339 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3341 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3342 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3345 /* We're trying to produce a constructor with a prohibited signature,
3346 as discussed above; handle here any cases we didn't catch then,
3348 reason
= invalid_copy_with_fn_template_rejection ();
3353 if (obj
!= NULL_TREE
)
3354 /* Aha, this is a conversion function. */
3355 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3356 access_path
, conversion_path
, complain
);
3358 cand
= add_function_candidate (candidates
, fn
, ctype
,
3359 first_arg
, arglist
, access_path
,
3360 conversion_path
, flags
, convs
, complain
);
3361 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3362 /* This situation can occur if a member template of a template
3363 class is specialized. Then, instantiate_template might return
3364 an instantiation of the specialization, in which case the
3365 DECL_TI_TEMPLATE field will point at the original
3366 specialization. For example:
3368 template <class T> struct S { template <class U> void f(U);
3369 template <> void f(int) {}; };
3373 Here, TMPL will be template <class U> S<double>::f(U).
3374 And, instantiate template will give us the specialization
3375 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3376 for this will point at template <class T> template <> S<T>::f(int),
3377 so that we can find the definition. For the purposes of
3378 overload resolution, however, we want the original TMPL. */
3379 cand
->template_decl
= build_template_info (tmpl
, targs
);
3381 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3382 cand
->explicit_targs
= explicit_targs
;
3386 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3387 access_path
, conversion_path
, 0, reason
, flags
);
3391 static struct z_candidate
*
3392 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3393 tree explicit_targs
, tree first_arg
,
3394 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3395 tree access_path
, tree conversion_path
, int flags
,
3396 unification_kind_t strict
, tsubst_flags_t complain
)
3399 add_template_candidate_real (candidates
, tmpl
, ctype
,
3400 explicit_targs
, first_arg
, arglist
,
3401 return_type
, access_path
, conversion_path
,
3402 flags
, NULL_TREE
, strict
, complain
);
3405 /* Create an overload candidate for the conversion function template TMPL,
3406 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3407 pointer-to-function which will in turn be called with the argument list
3408 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3409 passed on to implicit_conversion. */
3411 static struct z_candidate
*
3412 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3414 const vec
<tree
, va_gc
> *arglist
,
3415 tree return_type
, tree access_path
,
3416 tree conversion_path
, tsubst_flags_t complain
)
3418 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3419 core issue 2189, let's disable this candidate if there are any call
3425 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3426 NULL_TREE
, arglist
, return_type
, access_path
,
3427 conversion_path
, 0, obj
, DEDUCE_CALL
,
3431 /* The CANDS are the set of candidates that were considered for
3432 overload resolution. Return the set of viable candidates, or CANDS
3433 if none are viable. If any of the candidates were viable, set
3434 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3435 considered viable only if it is strictly viable. */
3437 static struct z_candidate
*
3438 splice_viable (struct z_candidate
*cands
,
3442 struct z_candidate
*viable
;
3443 struct z_candidate
**last_viable
;
3444 struct z_candidate
**cand
;
3445 bool found_strictly_viable
= false;
3447 /* Be strict inside templates, since build_over_call won't actually
3448 do the conversions to get pedwarns. */
3449 if (processing_template_decl
)
3453 last_viable
= &viable
;
3454 *any_viable_p
= false;
3459 struct z_candidate
*c
= *cand
;
3461 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3463 /* Be strict in the presence of a viable candidate. Also if
3464 there are template candidates, so that we get deduction errors
3465 for them instead of silently preferring a bad conversion. */
3467 if (viable
&& !found_strictly_viable
)
3469 /* Put any spliced near matches back onto the main list so
3470 that we see them if there is no strict match. */
3471 *any_viable_p
= false;
3472 *last_viable
= cands
;
3475 last_viable
= &viable
;
3479 if (strict_p
? c
->viable
== 1 : c
->viable
)
3484 last_viable
= &c
->next
;
3485 *any_viable_p
= true;
3487 found_strictly_viable
= true;
3493 return viable
? viable
: cands
;
3497 any_strictly_viable (struct z_candidate
*cands
)
3499 for (; cands
; cands
= cands
->next
)
3500 if (cands
->viable
== 1)
3505 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3506 words, it is about to become the "this" pointer for a member
3507 function call. Take the address of the object. */
3510 build_this (tree obj
)
3512 /* In a template, we are only concerned about the type of the
3513 expression, so we can take a shortcut. */
3514 if (processing_template_decl
)
3515 return build_address (obj
);
3517 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3520 /* Returns true iff functions are equivalent. Equivalent functions are
3521 not '==' only if one is a function-local extern function or if
3522 both are extern "C". */
3525 equal_functions (tree fn1
, tree fn2
)
3527 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3529 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3531 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3532 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3533 return decls_match (fn1
, fn2
);
3537 /* Print information about a candidate FN being rejected due to INFO. */
3540 print_conversion_rejection (location_t loc
, struct conversion_info
*info
,
3543 tree from
= info
->from
;
3545 from
= lvalue_type (from
);
3546 if (info
->n_arg
== -1)
3548 /* Conversion of implicit `this' argument failed. */
3549 if (!TYPE_P (info
->from
))
3550 /* A bad conversion for 'this' must be discarding cv-quals. */
3551 inform (loc
, " passing %qT as %<this%> "
3552 "argument discards qualifiers",
3555 inform (loc
, " no known conversion for implicit "
3556 "%<this%> parameter from %qH to %qI",
3557 from
, info
->to_type
);
3559 else if (!TYPE_P (info
->from
))
3561 if (info
->n_arg
>= 0)
3562 inform (loc
, " conversion of argument %d would be ill-formed:",
3564 perform_implicit_conversion (info
->to_type
, info
->from
,
3565 tf_warning_or_error
);
3567 else if (info
->n_arg
== -2)
3568 /* Conversion of conversion function return value failed. */
3569 inform (loc
, " no known conversion from %qH to %qI",
3570 from
, info
->to_type
);
3573 if (TREE_CODE (fn
) == FUNCTION_DECL
)
3574 loc
= get_fndecl_argument_location (fn
, info
->n_arg
);
3575 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3576 info
->n_arg
+ 1, from
, info
->to_type
);
3580 /* Print information about a candidate with WANT parameters and we found
3584 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3586 inform_n (loc
, want
,
3587 " candidate expects %d argument, %d provided",
3588 " candidate expects %d arguments, %d provided",
3592 /* Print information about one overload candidate CANDIDATE. MSGSTR
3593 is the text to print before the candidate itself.
3595 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3596 to have been run through gettext by the caller. This wart makes
3597 life simpler in print_z_candidates and for the translators. */
3600 print_z_candidate (location_t loc
, const char *msgstr
,
3601 struct z_candidate
*candidate
)
3603 const char *msg
= (msgstr
== NULL
3605 : ACONCAT ((_(msgstr
), " ", NULL
)));
3606 tree fn
= candidate
->fn
;
3607 if (flag_new_inheriting_ctors
)
3608 fn
= strip_inheriting_ctors (fn
);
3609 location_t cloc
= location_of (fn
);
3611 if (identifier_p (fn
))
3614 if (candidate
->num_convs
== 3)
3615 inform (cloc
, "%s%<%D(%T, %T, %T)%> (built-in)", msg
, fn
,
3616 candidate
->convs
[0]->type
,
3617 candidate
->convs
[1]->type
,
3618 candidate
->convs
[2]->type
);
3619 else if (candidate
->num_convs
== 2)
3620 inform (cloc
, "%s%<%D(%T, %T)%> (built-in)", msg
, fn
,
3621 candidate
->convs
[0]->type
,
3622 candidate
->convs
[1]->type
);
3624 inform (cloc
, "%s%<%D(%T)%> (built-in)", msg
, fn
,
3625 candidate
->convs
[0]->type
);
3627 else if (TYPE_P (fn
))
3628 inform (cloc
, "%s%qT (conversion)", msg
, fn
);
3629 else if (candidate
->viable
== -1)
3630 inform (cloc
, "%s%#qD (near match)", msg
, fn
);
3631 else if (DECL_DELETED_FN (fn
))
3632 inform (cloc
, "%s%#qD (deleted)", msg
, fn
);
3634 inform (cloc
, "%s%#qD", msg
, fn
);
3635 if (fn
!= candidate
->fn
)
3637 cloc
= location_of (candidate
->fn
);
3638 inform (cloc
, " inherited here");
3640 /* Give the user some information about why this candidate failed. */
3641 if (candidate
->reason
!= NULL
)
3643 struct rejection_reason
*r
= candidate
->reason
;
3648 print_arity_information (cloc
, r
->u
.arity
.actual
,
3649 r
->u
.arity
.expected
);
3651 case rr_arg_conversion
:
3652 print_conversion_rejection (cloc
, &r
->u
.conversion
, fn
);
3654 case rr_bad_arg_conversion
:
3655 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
, fn
);
3657 case rr_explicit_conversion
:
3658 inform (cloc
, " return type %qT of explicit conversion function "
3659 "cannot be converted to %qT with a qualification "
3660 "conversion", r
->u
.conversion
.from
,
3661 r
->u
.conversion
.to_type
);
3663 case rr_template_conversion
:
3664 inform (cloc
, " conversion from return type %qT of template "
3665 "conversion function specialization to %qT is not an "
3666 "exact match", r
->u
.conversion
.from
,
3667 r
->u
.conversion
.to_type
);
3669 case rr_template_unification
:
3670 /* We use template_unification_error_rejection if unification caused
3671 actual non-SFINAE errors, in which case we don't need to repeat
3673 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3675 inform (cloc
, " substitution of deduced template arguments "
3676 "resulted in errors seen above");
3679 /* Re-run template unification with diagnostics. */
3680 inform (cloc
, " template argument deduction/substitution failed:");
3681 fn_type_unification (r
->u
.template_unification
.tmpl
,
3682 r
->u
.template_unification
.explicit_targs
,
3684 (r
->u
.template_unification
.num_targs
)),
3685 r
->u
.template_unification
.args
,
3686 r
->u
.template_unification
.nargs
,
3687 r
->u
.template_unification
.return_type
,
3688 r
->u
.template_unification
.strict
,
3689 r
->u
.template_unification
.flags
,
3692 case rr_invalid_copy
:
3694 " a constructor taking a single argument of its own "
3695 "class type is invalid");
3697 case rr_constraint_failure
:
3699 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3700 tree args
= r
->u
.template_instantiation
.targs
;
3701 diagnose_constraints (cloc
, tmpl
, args
);
3704 case rr_inherited_ctor
:
3705 inform (cloc
, " an inherited constructor is not a candidate for "
3706 "initialization from an expression of the same or derived "
3711 /* This candidate didn't have any issues or we failed to
3712 handle a particular code. Either way... */
3719 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3721 struct z_candidate
*cand1
;
3722 struct z_candidate
**cand2
;
3727 /* Remove non-viable deleted candidates. */
3729 for (cand2
= &cand1
; *cand2
; )
3731 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3732 && !(*cand2
)->viable
3733 && DECL_DELETED_FN ((*cand2
)->fn
))
3734 *cand2
= (*cand2
)->next
;
3736 cand2
= &(*cand2
)->next
;
3738 /* ...if there are any non-deleted ones. */
3742 /* There may be duplicates in the set of candidates. We put off
3743 checking this condition as long as possible, since we have no way
3744 to eliminate duplicates from a set of functions in less than n^2
3745 time. Now we are about to emit an error message, so it is more
3746 permissible to go slowly. */
3747 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3749 tree fn
= cand1
->fn
;
3750 /* Skip builtin candidates and conversion functions. */
3753 cand2
= &cand1
->next
;
3756 if (DECL_P ((*cand2
)->fn
)
3757 && equal_functions (fn
, (*cand2
)->fn
))
3758 *cand2
= (*cand2
)->next
;
3760 cand2
= &(*cand2
)->next
;
3764 for (; candidates
; candidates
= candidates
->next
)
3765 print_z_candidate (loc
, N_("candidate:"), candidates
);
3768 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3769 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3770 the result of the conversion function to convert it to the final
3771 desired type. Merge the two sequences into a single sequence,
3772 and return the merged sequence. */
3775 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3778 bool bad
= user_seq
->bad_p
;
3780 gcc_assert (user_seq
->kind
== ck_user
);
3782 /* Find the end of the second conversion sequence. */
3783 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3785 /* The entire sequence is a user-conversion sequence. */
3786 (*t
)->user_conv_p
= true;
3791 if ((*t
)->rvaluedness_matches_p
)
3792 /* We're binding a reference directly to the result of the conversion.
3793 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3794 type, but we want it back. */
3795 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3797 /* Replace the identity conversion with the user conversion
3804 /* Handle overload resolution for initializing an object of class type from
3805 an initializer list. First we look for a suitable constructor that
3806 takes a std::initializer_list; if we don't find one, we then look for a
3807 non-list constructor.
3809 Parameters are as for add_candidates, except that the arguments are in
3810 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3811 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3814 add_list_candidates (tree fns
, tree first_arg
,
3815 const vec
<tree
, va_gc
> *args
, tree totype
,
3816 tree explicit_targs
, bool template_only
,
3817 tree conversion_path
, tree access_path
,
3819 struct z_candidate
**candidates
,
3820 tsubst_flags_t complain
)
3822 gcc_assert (*candidates
== NULL
);
3824 /* We're looking for a ctor for list-initialization. */
3825 flags
|= LOOKUP_LIST_INIT_CTOR
;
3826 /* And we don't allow narrowing conversions. We also use this flag to
3827 avoid the copy constructor call for copy-list-initialization. */
3828 flags
|= LOOKUP_NO_NARROWING
;
3830 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3831 tree init_list
= (*args
)[nart
];
3833 /* Always use the default constructor if the list is empty (DR 990). */
3834 if (CONSTRUCTOR_NELTS (init_list
) == 0
3835 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3837 /* If the class has a list ctor, try passing the list as a single
3838 argument first, but only consider list ctors. */
3839 else if (TYPE_HAS_LIST_CTOR (totype
))
3841 flags
|= LOOKUP_LIST_ONLY
;
3842 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3843 explicit_targs
, template_only
, conversion_path
,
3844 access_path
, flags
, candidates
, complain
);
3845 if (any_strictly_viable (*candidates
))
3849 /* Expand the CONSTRUCTOR into a new argument vec. */
3850 vec
<tree
, va_gc
> *new_args
;
3851 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3852 for (unsigned i
= 0; i
< nart
; ++i
)
3853 new_args
->quick_push ((*args
)[i
]);
3854 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3855 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3857 /* We aren't looking for list-ctors anymore. */
3858 flags
&= ~LOOKUP_LIST_ONLY
;
3859 /* We allow more user-defined conversions within an init-list. */
3860 flags
&= ~LOOKUP_NO_CONVERSION
;
3862 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3863 explicit_targs
, template_only
, conversion_path
,
3864 access_path
, flags
, candidates
, complain
);
3867 /* Returns the best overload candidate to perform the requested
3868 conversion. This function is used for three the overloading situations
3869 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3870 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3871 per [dcl.init.ref], so we ignore temporary bindings. */
3873 static struct z_candidate
*
3874 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3875 tsubst_flags_t complain
)
3877 struct z_candidate
*candidates
, *cand
;
3879 tree ctors
= NULL_TREE
;
3880 tree conv_fns
= NULL_TREE
;
3881 conversion
*conv
= NULL
;
3882 tree first_arg
= NULL_TREE
;
3883 vec
<tree
, va_gc
> *args
= NULL
;
3890 fromtype
= TREE_TYPE (expr
);
3892 /* We represent conversion within a hierarchy using RVALUE_CONV and
3893 BASE_CONV, as specified by [over.best.ics]; these become plain
3894 constructor calls, as specified in [dcl.init]. */
3895 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3896 || !DERIVED_FROM_P (totype
, fromtype
));
3898 if (CLASS_TYPE_P (totype
))
3899 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3900 creating a garbage BASELINK; constructors can't be inherited. */
3901 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3903 if (MAYBE_CLASS_TYPE_P (fromtype
))
3905 tree to_nonref
= non_reference (totype
);
3906 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3907 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3908 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3910 /* [class.conv.fct] A conversion function is never used to
3911 convert a (possibly cv-qualified) object to the (possibly
3912 cv-qualified) same object type (or a reference to it), to a
3913 (possibly cv-qualified) base class of that type (or a
3914 reference to it)... */
3917 conv_fns
= lookup_conversions (fromtype
);
3921 flags
|= LOOKUP_NO_CONVERSION
;
3922 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3923 flags
|= LOOKUP_NO_NARROWING
;
3925 /* It's OK to bind a temporary for converting constructor arguments, but
3926 not in converting the return value of a conversion operator. */
3927 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3928 | (flags
& LOOKUP_NO_NARROWING
));
3929 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3933 int ctorflags
= flags
;
3935 first_arg
= build_dummy_object (totype
);
3937 /* We should never try to call the abstract or base constructor
3939 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3940 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3942 args
= make_tree_vector_single (expr
);
3943 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3945 /* List-initialization. */
3946 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3947 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3948 ctorflags
, &candidates
, complain
);
3952 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3953 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3954 ctorflags
, &candidates
, complain
);
3957 for (cand
= candidates
; cand
; cand
= cand
->next
)
3959 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3961 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3962 set, then this is copy-initialization. In that case, "The
3963 result of the call is then used to direct-initialize the
3964 object that is the destination of the copy-initialization."
3967 We represent this in the conversion sequence with an
3968 rvalue conversion, which means a constructor call. */
3969 if (!TYPE_REF_P (totype
)
3970 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3972 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3978 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3979 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3984 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3986 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3987 struct z_candidate
*old_candidates
;
3989 /* If we are called to convert to a reference type, we are trying to
3990 find a direct binding, so don't even consider temporaries. If
3991 we don't find a direct binding, the caller will try again to
3992 look for a temporary binding. */
3993 if (TYPE_REF_P (totype
))
3994 convflags
|= LOOKUP_NO_TEMP_BIND
;
3996 old_candidates
= candidates
;
3997 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3999 conversion_path
, TYPE_BINFO (fromtype
),
4000 flags
, &candidates
, complain
);
4002 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
4004 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
4006 = implicit_conversion (totype
,
4009 /*c_cast_p=*/false, convflags
,
4012 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
4013 copy-initialization. In that case, "The result of the
4014 call is then used to direct-initialize the object that is
4015 the destination of the copy-initialization." [dcl.init]
4017 We represent this in the conversion sequence with an
4018 rvalue conversion, which means a constructor call. But
4019 don't add a second rvalue conversion if there's already
4020 one there. Which there really shouldn't be, but it's
4021 harmless since we'd add it here anyway. */
4022 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
4023 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
4024 ics
= build_conv (ck_rvalue
, totype
, ics
);
4026 cand
->second_conv
= ics
;
4031 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
4033 EXPR_LOCATION (expr
));
4035 else if (TYPE_REF_P (totype
) && !ics
->rvaluedness_matches_p
4036 && TREE_CODE (TREE_TYPE (totype
)) != FUNCTION_TYPE
)
4038 /* If we are called to convert to a reference type, we are trying
4039 to find a direct binding per [over.match.ref], so rvaluedness
4040 must match for non-functions. */
4043 else if (DECL_NONCONVERTING_P (cand
->fn
)
4044 && ics
->rank
> cr_exact
)
4046 /* 13.3.1.5: For direct-initialization, those explicit
4047 conversion functions that are not hidden within S and
4048 yield type T or a type that can be converted to type T
4049 with a qualification conversion (4.4) are also candidate
4051 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
4052 I've raised this issue with the committee. --jason 9/2011 */
4054 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
4056 else if (cand
->viable
== 1 && ics
->bad_p
)
4060 = bad_arg_conversion_rejection (NULL_TREE
, -2,
4062 EXPR_LOCATION (expr
));
4064 else if (primary_template_specialization_p (cand
->fn
)
4065 && ics
->rank
> cr_exact
)
4067 /* 13.3.3.1.2: If the user-defined conversion is specified by
4068 a specialization of a conversion function template, the
4069 second standard conversion sequence shall have exact match
4072 cand
->reason
= template_conversion_rejection (rettype
, totype
);
4077 candidates
= splice_viable (candidates
, false, &any_viable_p
);
4081 release_tree_vector (args
);
4085 cand
= tourney (candidates
, complain
);
4088 if (complain
& tf_error
)
4090 auto_diagnostic_group d
;
4091 error ("conversion from %qH to %qI is ambiguous",
4093 print_z_candidates (location_of (expr
), candidates
);
4096 cand
= candidates
; /* any one will do */
4097 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
4098 cand
->second_conv
->user_conv_p
= true;
4099 if (!any_strictly_viable (candidates
))
4100 cand
->second_conv
->bad_p
= true;
4101 if (flags
& LOOKUP_ONLYCONVERTING
)
4102 cand
->second_conv
->need_temporary_p
= true;
4103 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
4104 ambiguous conversion is no worse than another user-defined
4111 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
4112 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
4113 else if (cand
->second_conv
->kind
== ck_rvalue
)
4114 /* DR 5: [in the first step of copy-initialization]...if the function
4115 is a constructor, the call initializes a temporary of the
4116 cv-unqualified version of the destination type. */
4117 convtype
= cv_unqualified (totype
);
4120 /* Build the user conversion sequence. */
4124 build_identity_conv (TREE_TYPE (expr
), expr
));
4126 if (cand
->viable
== -1)
4129 /* We're performing the maybe-rvalue overload resolution and
4130 a conversion function is in play. Reject converting the return
4131 value of the conversion function to a base class. */
4132 if ((flags
& LOOKUP_PREFER_RVALUE
) && !DECL_CONSTRUCTOR_P (cand
->fn
))
4133 for (conversion
*t
= cand
->second_conv
; t
; t
= next_conversion (t
))
4134 if (t
->kind
== ck_base
)
4137 /* Remember that this was a list-initialization. */
4138 if (flags
& LOOKUP_NO_NARROWING
)
4139 conv
->check_narrowing
= true;
4141 /* Combine it with the second conversion sequence. */
4142 cand
->second_conv
= merge_conversion_sequences (conv
,
4148 /* Wrapper for above. */
4151 build_user_type_conversion (tree totype
, tree expr
, int flags
,
4152 tsubst_flags_t complain
)
4154 struct z_candidate
*cand
;
4157 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4158 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
4162 if (cand
->second_conv
->kind
== ck_ambig
)
4163 ret
= error_mark_node
;
4166 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4167 ret
= convert_from_reference (expr
);
4173 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4177 /* Worker for build_converted_constant_expr. */
4180 build_converted_constant_expr_internal (tree type
, tree expr
,
4181 int flags
, tsubst_flags_t complain
)
4186 location_t loc
= cp_expr_loc_or_input_loc (expr
);
4188 if (error_operand_p (expr
))
4189 return error_mark_node
;
4191 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4192 p
= conversion_obstack_alloc (0);
4194 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4195 /*c_cast_p=*/false, flags
, complain
);
4197 /* A converted constant expression of type T is an expression, implicitly
4198 converted to type T, where the converted expression is a constant
4199 expression and the implicit conversion sequence contains only
4201 * user-defined conversions,
4202 * lvalue-to-rvalue conversions (7.1),
4203 * array-to-pointer conversions (7.2),
4204 * function-to-pointer conversions (7.3),
4205 * qualification conversions (7.5),
4206 * integral promotions (7.6),
4207 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4208 * null pointer conversions (7.11) from std::nullptr_t,
4209 * null member pointer conversions (7.12) from std::nullptr_t, and
4210 * function pointer conversions (7.13),
4212 and where the reference binding (if any) binds directly. */
4214 for (conversion
*c
= conv
;
4215 conv
&& c
->kind
!= ck_identity
;
4216 c
= next_conversion (c
))
4220 /* A conversion function is OK. If it isn't constexpr, we'll
4221 complain later that the argument isn't constant. */
4223 /* The lvalue-to-rvalue conversion is OK. */
4225 /* Array-to-pointer and function-to-pointer. */
4227 /* Function pointer conversions. */
4229 /* Qualification conversions. */
4234 if (c
->need_temporary_p
)
4236 if (complain
& tf_error
)
4237 error_at (loc
, "initializing %qH with %qI in converted "
4238 "constant expression does not bind directly",
4239 type
, next_conversion (c
)->type
);
4248 t
= next_conversion (c
)->type
;
4249 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4250 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4251 /* Integral promotion or conversion. */
4253 if (NULLPTR_TYPE_P (t
))
4254 /* Conversion from nullptr to pointer or pointer-to-member. */
4257 if (complain
& tf_error
)
4258 error_at (loc
, "conversion from %qH to %qI in a "
4259 "converted constant expression", t
, type
);
4268 /* Avoid confusing convert_nontype_argument by introducing
4269 a redundant conversion to the same reference type. */
4270 if (conv
&& conv
->kind
== ck_ref_bind
4271 && REFERENCE_REF_P (expr
))
4273 tree ref
= TREE_OPERAND (expr
, 0);
4274 if (same_type_p (type
, TREE_TYPE (ref
)))
4280 /* Don't copy a class in a template. */
4281 if (CLASS_TYPE_P (type
) && conv
->kind
== ck_rvalue
4282 && processing_template_decl
)
4283 conv
= next_conversion (conv
);
4285 conv
->check_narrowing
= true;
4286 conv
->check_narrowing_const_only
= true;
4287 expr
= convert_like (conv
, expr
, complain
);
4291 if (complain
& tf_error
)
4292 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4293 TREE_TYPE (expr
), type
);
4294 expr
= error_mark_node
;
4297 /* Free all the conversions we allocated. */
4298 obstack_free (&conversion_obstack
, p
);
4303 /* Subroutine of convert_nontype_argument.
4305 EXPR is an expression used in a context that requires a converted
4306 constant-expression, such as a template non-type parameter. Do any
4307 necessary conversions (that are permitted for converted
4308 constant-expressions) to convert it to the desired type.
4310 This function doesn't consider explicit conversion functions. If
4311 you mean to use "a contextually converted constant expression of type
4312 bool", use build_converted_constant_bool_expr.
4314 If conversion is successful, returns the converted expression;
4315 otherwise, returns error_mark_node. */
4318 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4320 return build_converted_constant_expr_internal (type
, expr
, LOOKUP_IMPLICIT
,
4324 /* Used to create "a contextually converted constant expression of type
4325 bool". This differs from build_converted_constant_expr in that it
4326 also considers explicit conversion functions. */
4329 build_converted_constant_bool_expr (tree expr
, tsubst_flags_t complain
)
4331 return build_converted_constant_expr_internal (boolean_type_node
, expr
,
4332 LOOKUP_NORMAL
, complain
);
4335 /* Do any initial processing on the arguments to a function call. */
4337 static vec
<tree
, va_gc
> *
4338 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4343 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4345 if (error_operand_p (arg
))
4347 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4349 if (complain
& tf_error
)
4350 error ("invalid use of void expression");
4353 else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg
), arg
, complain
))
4359 /* Perform overload resolution on FN, which is called with the ARGS.
4361 Return the candidate function selected by overload resolution, or
4362 NULL if the event that overload resolution failed. In the case
4363 that overload resolution fails, *CANDIDATES will be the set of
4364 candidates considered, and ANY_VIABLE_P will be set to true or
4365 false to indicate whether or not any of the candidates were
4368 The ARGS should already have gone through RESOLVE_ARGS before this
4369 function is called. */
4371 static struct z_candidate
*
4372 perform_overload_resolution (tree fn
,
4373 const vec
<tree
, va_gc
> *args
,
4374 struct z_candidate
**candidates
,
4375 bool *any_viable_p
, tsubst_flags_t complain
)
4377 struct z_candidate
*cand
;
4378 tree explicit_targs
;
4381 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4383 explicit_targs
= NULL_TREE
;
4387 *any_viable_p
= true;
4390 gcc_assert (OVL_P (fn
) || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4392 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4394 explicit_targs
= TREE_OPERAND (fn
, 1);
4395 fn
= TREE_OPERAND (fn
, 0);
4399 /* Add the various candidate functions. */
4400 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4401 explicit_targs
, template_only
,
4402 /*conversion_path=*/NULL_TREE
,
4403 /*access_path=*/NULL_TREE
,
4405 candidates
, complain
);
4407 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4409 cand
= tourney (*candidates
, complain
);
4413 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4417 /* Print an error message about being unable to build a call to FN with
4418 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4419 be located; CANDIDATES is a possibly empty list of such
4423 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4424 struct z_candidate
*candidates
)
4426 tree targs
= NULL_TREE
;
4427 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4429 targs
= TREE_OPERAND (fn
, 1);
4430 fn
= TREE_OPERAND (fn
, 0);
4432 tree name
= OVL_NAME (fn
);
4433 location_t loc
= location_of (name
);
4435 name
= lookup_template_function (name
, targs
);
4437 auto_diagnostic_group d
;
4438 if (!any_strictly_viable (candidates
))
4439 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4440 name
, build_tree_list_vec (args
));
4442 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4443 name
, build_tree_list_vec (args
));
4445 print_z_candidates (loc
, candidates
);
4448 /* Return an expression for a call to FN (a namespace-scope function,
4449 or a static member function) with the ARGS. This may change
4453 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4454 tsubst_flags_t complain
)
4456 struct z_candidate
*candidates
, *cand
;
4461 if (args
!= NULL
&& *args
!= NULL
)
4463 *args
= resolve_args (*args
, complain
);
4465 return error_mark_node
;
4469 tm_malloc_replacement (fn
);
4471 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4472 p
= conversion_obstack_alloc (0);
4474 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4479 if (complain
& tf_error
)
4481 // If there is a single (non-viable) function candidate,
4482 // let the error be diagnosed by cp_build_function_call_vec.
4483 if (!any_viable_p
&& candidates
&& ! candidates
->next
4484 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4485 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4487 // Otherwise, emit notes for non-viable candidates.
4488 print_error_for_call_failure (fn
, *args
, candidates
);
4490 result
= error_mark_node
;
4494 int flags
= LOOKUP_NORMAL
;
4495 /* If fn is template_id_expr, the call has explicit template arguments
4496 (e.g. func<int>(5)), communicate this info to build_over_call
4497 through flags so that later we can use it to decide whether to warn
4498 about peculiar null pointer conversion. */
4499 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4501 /* If overload resolution selects a specialization of a
4502 function concept for non-dependent template arguments,
4503 the expression is true if the constraints are satisfied
4504 and false otherwise.
4506 NOTE: This is an extension of Concepts Lite TS that
4507 allows constraints to be used in expressions. */
4508 if (flag_concepts
&& !processing_template_decl
)
4510 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4511 tree targs
= DECL_TI_ARGS (cand
->fn
);
4512 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4513 if (DECL_DECLARED_CONCEPT_P (decl
))
4514 return evaluate_function_concept (decl
, targs
);
4517 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4520 result
= build_over_call (cand
, flags
, complain
);
4523 /* Free all the conversions we allocated. */
4524 obstack_free (&conversion_obstack
, p
);
4529 /* Build a call to a global operator new. FNNAME is the name of the
4530 operator (either "operator new" or "operator new[]") and ARGS are
4531 the arguments provided. This may change ARGS. *SIZE points to the
4532 total number of bytes required by the allocation, and is updated if
4533 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4534 be used. If this function determines that no cookie should be
4535 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4536 is not NULL_TREE, it is evaluated before calculating the final
4537 array size, and if it fails, the array size is replaced with
4538 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4539 is non-NULL, it will be set, upon return, to the allocation
4543 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4544 tree
*size
, tree
*cookie_size
,
4545 tree align_arg
, tree size_check
,
4546 tree
*fn
, tsubst_flags_t complain
)
4548 tree original_size
= *size
;
4550 struct z_candidate
*candidates
;
4551 struct z_candidate
*cand
= NULL
;
4556 /* Set to (size_t)-1 if the size check fails. */
4557 if (size_check
!= NULL_TREE
)
4559 tree errval
= TYPE_MAX_VALUE (sizetype
);
4560 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4561 errval
= throw_bad_array_new_length ();
4562 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4563 original_size
, errval
);
4565 vec_safe_insert (*args
, 0, *size
);
4566 *args
= resolve_args (*args
, complain
);
4568 return error_mark_node
;
4574 If this lookup fails to find the name, or if the allocated type
4575 is not a class type, the allocation function's name is looked
4576 up in the global scope.
4578 we disregard block-scope declarations of "operator new". */
4579 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4580 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4584 vec
<tree
, va_gc
>* align_args
4585 = vec_copy_and_insert (*args
, align_arg
, 1);
4586 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4587 &any_viable_p
, tf_none
);
4590 /* If no aligned allocation function matches, try again without the
4594 /* Figure out what function is being called. */
4596 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4599 /* If no suitable function could be found, issue an error message
4603 if (complain
& tf_error
)
4604 print_error_for_call_failure (fns
, *args
, candidates
);
4605 return error_mark_node
;
4608 /* If a cookie is required, add some extra space. Whether
4609 or not a cookie is required cannot be determined until
4610 after we know which function was called. */
4613 bool use_cookie
= true;
4616 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4617 /* Skip the size_t parameter. */
4618 arg_types
= TREE_CHAIN (arg_types
);
4619 /* Check the remaining parameters (if any). */
4621 && TREE_CHAIN (arg_types
) == void_list_node
4622 && same_type_p (TREE_VALUE (arg_types
),
4625 /* If we need a cookie, adjust the number of bytes allocated. */
4628 /* Update the total size. */
4629 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4632 /* Set to (size_t)-1 if the size check fails. */
4633 gcc_assert (size_check
!= NULL_TREE
);
4634 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4635 *size
, TYPE_MAX_VALUE (sizetype
));
4637 /* Update the argument list to reflect the adjusted size. */
4638 (**args
)[0] = *size
;
4641 *cookie_size
= NULL_TREE
;
4644 /* Tell our caller which function we decided to call. */
4648 /* Build the CALL_EXPR. */
4649 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4652 /* Build a new call to operator(). This may change ARGS. */
4655 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4657 struct z_candidate
*candidates
= 0, *cand
;
4658 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4660 tree result
= NULL_TREE
;
4663 obj
= mark_lvalue_use (obj
);
4665 if (error_operand_p (obj
))
4666 return error_mark_node
;
4668 tree type
= TREE_TYPE (obj
);
4670 obj
= prep_operand (obj
);
4672 if (TYPE_PTRMEMFUNC_P (type
))
4674 if (complain
& tf_error
)
4675 /* It's no good looking for an overloaded operator() on a
4676 pointer-to-member-function. */
4677 error ("pointer-to-member function %qE cannot be called without "
4678 "an object; consider using %<.*%> or %<->*%>", obj
);
4679 return error_mark_node
;
4682 if (TYPE_BINFO (type
))
4684 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4685 if (fns
== error_mark_node
)
4686 return error_mark_node
;
4691 if (args
!= NULL
&& *args
!= NULL
)
4693 *args
= resolve_args (*args
, complain
);
4695 return error_mark_node
;
4698 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4699 p
= conversion_obstack_alloc (0);
4703 first_mem_arg
= obj
;
4705 add_candidates (BASELINK_FUNCTIONS (fns
),
4706 first_mem_arg
, *args
, NULL_TREE
,
4708 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4709 LOOKUP_NORMAL
, &candidates
, complain
);
4712 convs
= lookup_conversions (type
);
4714 for (; convs
; convs
= TREE_CHAIN (convs
))
4716 tree totype
= TREE_TYPE (convs
);
4718 if (TYPE_PTRFN_P (totype
)
4719 || TYPE_REFFN_P (totype
)
4720 || (TYPE_REF_P (totype
)
4721 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4722 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4726 if (DECL_NONCONVERTING_P (fn
))
4729 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4730 add_template_conv_candidate
4731 (&candidates
, fn
, obj
, *args
, totype
,
4732 /*access_path=*/NULL_TREE
,
4733 /*conversion_path=*/NULL_TREE
, complain
);
4735 add_conv_candidate (&candidates
, fn
, obj
,
4736 *args
, /*conversion_path=*/NULL_TREE
,
4737 /*access_path=*/NULL_TREE
, complain
);
4741 /* Be strict here because if we choose a bad conversion candidate, the
4742 errors we get won't mention the call context. */
4743 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4746 if (complain
& tf_error
)
4748 auto_diagnostic_group d
;
4749 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4750 build_tree_list_vec (*args
));
4751 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4753 result
= error_mark_node
;
4757 cand
= tourney (candidates
, complain
);
4760 if (complain
& tf_error
)
4762 auto_diagnostic_group d
;
4763 error ("call of %<(%T) (%A)%> is ambiguous",
4764 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4765 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4767 result
= error_mark_node
;
4769 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4770 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4771 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4772 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4775 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4776 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4780 gcc_checking_assert (TYPE_P (cand
->fn
));
4781 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4783 obj
= convert_from_reference (obj
);
4784 result
= cp_build_function_call_vec (obj
, args
, complain
);
4788 /* Free all the conversions we allocated. */
4789 obstack_free (&conversion_obstack
, p
);
4794 /* Wrapper for above. */
4797 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4800 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4801 ret
= build_op_call_1 (obj
, args
, complain
);
4802 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4806 /* Called by op_error to prepare format strings suitable for the error
4807 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4808 and a suffix (controlled by NTYPES). */
4811 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4815 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4816 : G_("no match for "), errmsg
, NULL
);
4819 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4820 else if (ntypes
== 2)
4821 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4823 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4829 op_error (const op_location_t
&loc
,
4830 enum tree_code code
, enum tree_code code2
,
4831 tree arg1
, tree arg2
, tree arg3
, bool match
)
4833 bool assop
= code
== MODIFY_EXPR
;
4834 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4839 if (flag_diagnostics_show_caret
)
4840 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4842 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4844 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4845 "in %<%E ? %E : %E%>"), 3, match
),
4847 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4850 case POSTINCREMENT_EXPR
:
4851 case POSTDECREMENT_EXPR
:
4852 if (flag_diagnostics_show_caret
)
4853 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4854 opname
, TREE_TYPE (arg1
));
4856 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4858 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4862 if (flag_diagnostics_show_caret
)
4863 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4864 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4866 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4868 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4873 if (flag_diagnostics_show_caret
)
4874 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4875 opname
, TREE_TYPE (arg1
));
4877 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4878 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4883 if (flag_diagnostics_show_caret
)
4885 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4887 op_error_string (G_("%<operator%s%>"), 2, match
),
4888 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4891 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4893 opname
, arg1
, opname
, arg2
,
4894 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4896 if (flag_diagnostics_show_caret
)
4897 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4898 opname
, TREE_TYPE (arg1
));
4900 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4902 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4907 /* Return the implicit conversion sequence that could be used to
4908 convert E1 to E2 in [expr.cond]. */
4911 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4913 tree t1
= non_reference (TREE_TYPE (e1
));
4914 tree t2
= non_reference (TREE_TYPE (e2
));
4920 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4921 implicitly converted (clause _conv_) to the type "lvalue reference to
4922 T2", subject to the constraint that in the conversion the
4923 reference must bind directly (_dcl.init.ref_) to an lvalue.
4925 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4926 implicitly converted to the type "rvalue reference to T2", subject to
4927 the constraint that the reference must bind directly. */
4930 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4931 conv
= implicit_conversion (rtype
,
4935 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4936 |LOOKUP_ONLYCONVERTING
,
4938 if (conv
&& !conv
->bad_p
)
4942 /* If E2 is a prvalue or if neither of the conversions above can be done
4943 and at least one of the operands has (possibly cv-qualified) class
4945 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4950 If E1 and E2 have class type, and the underlying class types are
4951 the same or one is a base class of the other: E1 can be converted
4952 to match E2 if the class of T2 is the same type as, or a base
4953 class of, the class of T1, and the cv-qualification of T2 is the
4954 same cv-qualification as, or a greater cv-qualification than, the
4955 cv-qualification of T1. If the conversion is applied, E1 is
4956 changed to an rvalue of type T2 that still refers to the original
4957 source class object (or the appropriate subobject thereof). */
4958 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4959 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4961 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4963 conv
= build_identity_conv (t1
, e1
);
4964 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4965 TYPE_MAIN_VARIANT (t2
)))
4966 conv
= build_conv (ck_base
, t2
, conv
);
4968 conv
= build_conv (ck_rvalue
, t2
, conv
);
4977 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4978 converted to the type that expression E2 would have if E2 were
4979 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4980 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4981 LOOKUP_IMPLICIT
, complain
);
4984 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4985 arguments to the conditional expression. */
4988 build_conditional_expr_1 (const op_location_t
&loc
,
4989 tree arg1
, tree arg2
, tree arg3
,
4990 tsubst_flags_t complain
)
4994 tree result
= NULL_TREE
;
4995 tree result_type
= NULL_TREE
;
4996 bool is_glvalue
= true;
4997 struct z_candidate
*candidates
= 0;
4998 struct z_candidate
*cand
;
5000 tree orig_arg2
, orig_arg3
;
5002 /* As a G++ extension, the second argument to the conditional can be
5003 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
5004 c'.) If the second operand is omitted, make sure it is
5005 calculated only once. */
5008 if (complain
& tf_error
)
5009 pedwarn (loc
, OPT_Wpedantic
,
5010 "ISO C++ forbids omitting the middle term of "
5011 "a %<?:%> expression");
5013 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
5014 warn_for_omitted_condop (loc
, arg1
);
5016 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
5017 if (lvalue_p (arg1
))
5018 arg2
= arg1
= cp_stabilize_reference (arg1
);
5020 arg2
= arg1
= cp_save_expr (arg1
);
5023 /* If something has already gone wrong, just pass that fact up the
5025 if (error_operand_p (arg1
)
5026 || error_operand_p (arg2
)
5027 || error_operand_p (arg3
))
5028 return error_mark_node
;
5033 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
5035 tree arg1_type
= TREE_TYPE (arg1
);
5037 /* If arg1 is another cond_expr choosing between -1 and 0,
5038 then we can use its comparison. It may help to avoid
5039 additional comparison, produce more accurate diagnostics
5040 and enables folding. */
5041 if (TREE_CODE (arg1
) == VEC_COND_EXPR
5042 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
5043 && integer_zerop (TREE_OPERAND (arg1
, 2)))
5044 arg1
= TREE_OPERAND (arg1
, 0);
5046 arg1
= force_rvalue (arg1
, complain
);
5047 arg2
= force_rvalue (arg2
, complain
);
5048 arg3
= force_rvalue (arg3
, complain
);
5050 /* force_rvalue can return error_mark on valid arguments. */
5051 if (error_operand_p (arg1
)
5052 || error_operand_p (arg2
)
5053 || error_operand_p (arg3
))
5054 return error_mark_node
;
5056 arg2_type
= TREE_TYPE (arg2
);
5057 arg3_type
= TREE_TYPE (arg3
);
5059 if (!VECTOR_TYPE_P (arg2_type
)
5060 && !VECTOR_TYPE_P (arg3_type
))
5062 /* Rely on the error messages of the scalar version. */
5063 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
5064 orig_arg2
, orig_arg3
, complain
);
5065 if (scal
== error_mark_node
)
5066 return error_mark_node
;
5067 tree stype
= TREE_TYPE (scal
);
5068 tree ctype
= TREE_TYPE (arg1_type
);
5069 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
5070 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
5072 if (complain
& tf_error
)
5073 error_at (loc
, "inferred scalar type %qT is not an integer or "
5074 "floating-point type of the same size as %qT", stype
,
5075 COMPARISON_CLASS_P (arg1
)
5076 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
5078 return error_mark_node
;
5081 tree vtype
= build_opaque_vector_type (stype
,
5082 TYPE_VECTOR_SUBPARTS (arg1_type
));
5083 /* We could pass complain & tf_warning to unsafe_conversion_p,
5084 but the warnings (like Wsign-conversion) have already been
5085 given by the scalar build_conditional_expr_1. We still check
5086 unsafe_conversion_p to forbid truncating long long -> float. */
5087 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
5089 if (complain
& tf_error
)
5090 error_at (loc
, "conversion of scalar %qH to vector %qI "
5091 "involves truncation", arg2_type
, vtype
);
5092 return error_mark_node
;
5094 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
5096 if (complain
& tf_error
)
5097 error_at (loc
, "conversion of scalar %qH to vector %qI "
5098 "involves truncation", arg3_type
, vtype
);
5099 return error_mark_node
;
5102 arg2
= cp_convert (stype
, arg2
, complain
);
5103 arg2
= save_expr (arg2
);
5104 arg2
= build_vector_from_val (vtype
, arg2
);
5106 arg3
= cp_convert (stype
, arg3
, complain
);
5107 arg3
= save_expr (arg3
);
5108 arg3
= build_vector_from_val (vtype
, arg3
);
5112 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5114 enum stv_conv convert_flag
=
5115 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5116 complain
& tf_error
);
5118 switch (convert_flag
)
5121 return error_mark_node
;
5124 arg2
= save_expr (arg2
);
5125 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5126 arg2
= build_vector_from_val (arg3_type
, arg2
);
5127 arg2_type
= TREE_TYPE (arg2
);
5132 arg3
= save_expr (arg3
);
5133 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5134 arg3
= build_vector_from_val (arg2_type
, arg3
);
5135 arg3_type
= TREE_TYPE (arg3
);
5143 if (!same_type_p (arg2_type
, arg3_type
)
5144 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5145 TYPE_VECTOR_SUBPARTS (arg2_type
))
5146 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5148 if (complain
& tf_error
)
5150 "incompatible vector types in conditional expression: "
5151 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5152 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5153 return error_mark_node
;
5156 if (!COMPARISON_CLASS_P (arg1
))
5158 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5159 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5161 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5166 The first expression is implicitly converted to bool (clause
5168 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5170 if (error_operand_p (arg1
))
5171 return error_mark_node
;
5175 If either the second or the third operand has type (possibly
5176 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5177 array-to-pointer (_conv.array_), and function-to-pointer
5178 (_conv.func_) standard conversions are performed on the second
5179 and third operands. */
5180 arg2_type
= unlowered_expr_type (arg2
);
5181 arg3_type
= unlowered_expr_type (arg3
);
5182 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5184 /* 'void' won't help in resolving an overloaded expression on the
5185 other side, so require it to resolve by itself. */
5186 if (arg2_type
== unknown_type_node
)
5188 arg2
= resolve_nondeduced_context_or_error (arg2
, complain
);
5189 arg2_type
= TREE_TYPE (arg2
);
5191 if (arg3_type
== unknown_type_node
)
5193 arg3
= resolve_nondeduced_context_or_error (arg3
, complain
);
5194 arg3_type
= TREE_TYPE (arg3
);
5199 One of the following shall hold:
5201 --The second or the third operand (but not both) is a
5202 throw-expression (_except.throw_); the result is of the type
5203 and value category of the other.
5205 --Both the second and the third operands have type void; the
5206 result is of type void and is a prvalue. */
5207 if (TREE_CODE (arg2
) == THROW_EXPR
5208 && TREE_CODE (arg3
) != THROW_EXPR
)
5210 result_type
= arg3_type
;
5211 is_glvalue
= glvalue_p (arg3
);
5213 else if (TREE_CODE (arg2
) != THROW_EXPR
5214 && TREE_CODE (arg3
) == THROW_EXPR
)
5216 result_type
= arg2_type
;
5217 is_glvalue
= glvalue_p (arg2
);
5219 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5221 result_type
= void_type_node
;
5226 if (complain
& tf_error
)
5228 if (VOID_TYPE_P (arg2_type
))
5229 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5230 "second operand to the conditional operator "
5231 "is of type %<void%>, but the third operand is "
5232 "neither a throw-expression nor of type %<void%>");
5234 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5235 "third operand to the conditional operator "
5236 "is of type %<void%>, but the second operand is "
5237 "neither a throw-expression nor of type %<void%>");
5239 return error_mark_node
;
5242 goto valid_operands
;
5246 Otherwise, if the second and third operand have different types,
5247 and either has (possibly cv-qualified) class type, or if both are
5248 glvalues of the same value category and the same type except for
5249 cv-qualification, an attempt is made to convert each of those operands
5250 to the type of the other. */
5251 else if (!same_type_p (arg2_type
, arg3_type
)
5252 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5253 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5255 && glvalue_p (arg2
) && glvalue_p (arg3
)
5256 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5260 bool converted
= false;
5262 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5263 p
= conversion_obstack_alloc (0);
5265 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5266 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5270 If both can be converted, or one can be converted but the
5271 conversion is ambiguous, the program is ill-formed. If
5272 neither can be converted, the operands are left unchanged and
5273 further checking is performed as described below. If exactly
5274 one conversion is possible, that conversion is applied to the
5275 chosen operand and the converted operand is used in place of
5276 the original operand for the remainder of this section. */
5277 if ((conv2
&& !conv2
->bad_p
5278 && conv3
&& !conv3
->bad_p
)
5279 || (conv2
&& conv2
->kind
== ck_ambig
)
5280 || (conv3
&& conv3
->kind
== ck_ambig
))
5282 if (complain
& tf_error
)
5284 error_at (loc
, "operands to %<?:%> have different types "
5286 arg2_type
, arg3_type
);
5287 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5288 inform (loc
, " and each type can be converted to the other");
5289 else if (conv2
&& conv2
->kind
== ck_ambig
)
5290 convert_like (conv2
, arg2
, complain
);
5292 convert_like (conv3
, arg3
, complain
);
5294 result
= error_mark_node
;
5296 else if (conv2
&& !conv2
->bad_p
)
5298 arg2
= convert_like (conv2
, arg2
, complain
);
5299 arg2
= convert_from_reference (arg2
);
5300 arg2_type
= TREE_TYPE (arg2
);
5301 /* Even if CONV2 is a valid conversion, the result of the
5302 conversion may be invalid. For example, if ARG3 has type
5303 "volatile X", and X does not have a copy constructor
5304 accepting a "volatile X&", then even if ARG2 can be
5305 converted to X, the conversion will fail. */
5306 if (error_operand_p (arg2
))
5307 result
= error_mark_node
;
5310 else if (conv3
&& !conv3
->bad_p
)
5312 arg3
= convert_like (conv3
, arg3
, complain
);
5313 arg3
= convert_from_reference (arg3
);
5314 arg3_type
= TREE_TYPE (arg3
);
5315 if (error_operand_p (arg3
))
5316 result
= error_mark_node
;
5320 /* Free all the conversions we allocated. */
5321 obstack_free (&conversion_obstack
, p
);
5326 /* If, after the conversion, both operands have class type,
5327 treat the cv-qualification of both operands as if it were the
5328 union of the cv-qualification of the operands.
5330 The standard is not clear about what to do in this
5331 circumstance. For example, if the first operand has type
5332 "const X" and the second operand has a user-defined
5333 conversion to "volatile X", what is the type of the second
5334 operand after this step? Making it be "const X" (matching
5335 the first operand) seems wrong, as that discards the
5336 qualification without actually performing a copy. Leaving it
5337 as "volatile X" seems wrong as that will result in the
5338 conditional expression failing altogether, even though,
5339 according to this step, the one operand could be converted to
5340 the type of the other. */
5342 && CLASS_TYPE_P (arg2_type
)
5343 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5344 arg2_type
= arg3_type
=
5345 cp_build_qualified_type (arg2_type
,
5346 cp_type_quals (arg2_type
)
5347 | cp_type_quals (arg3_type
));
5352 If the second and third operands are glvalues of the same value
5353 category and have the same type, the result is of that type and
5355 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5356 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5357 && same_type_p (arg2_type
, arg3_type
))
5359 result_type
= arg2_type
;
5360 arg2
= mark_lvalue_use (arg2
);
5361 arg3
= mark_lvalue_use (arg3
);
5362 goto valid_operands
;
5367 Otherwise, the result is an rvalue. If the second and third
5368 operand do not have the same type, and either has (possibly
5369 cv-qualified) class type, overload resolution is used to
5370 determine the conversions (if any) to be applied to the operands
5371 (_over.match.oper_, _over.built_). */
5373 if (!same_type_p (arg2_type
, arg3_type
)
5374 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5380 /* Rearrange the arguments so that add_builtin_candidate only has
5381 to know about two args. In build_builtin_candidate, the
5382 arguments are unscrambled. */
5386 add_builtin_candidates (&candidates
,
5389 ovl_op_identifier (false, COND_EXPR
),
5391 LOOKUP_NORMAL
, complain
);
5395 If the overload resolution fails, the program is
5397 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5400 if (complain
& tf_error
)
5401 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5402 arg2_type
, arg3_type
);
5403 return error_mark_node
;
5405 cand
= tourney (candidates
, complain
);
5408 if (complain
& tf_error
)
5410 auto_diagnostic_group d
;
5411 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5412 print_z_candidates (loc
, candidates
);
5414 return error_mark_node
;
5419 Otherwise, the conversions thus determined are applied, and
5420 the converted operands are used in place of the original
5421 operands for the remainder of this section. */
5422 conv
= cand
->convs
[0];
5423 arg1
= convert_like (conv
, arg1
, complain
);
5424 conv
= cand
->convs
[1];
5425 arg2
= convert_like (conv
, arg2
, complain
);
5426 arg2_type
= TREE_TYPE (arg2
);
5427 conv
= cand
->convs
[2];
5428 arg3
= convert_like (conv
, arg3
, complain
);
5429 arg3_type
= TREE_TYPE (arg3
);
5434 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5435 and function-to-pointer (_conv.func_) standard conversions are
5436 performed on the second and third operands.
5438 We need to force the lvalue-to-rvalue conversion here for class types,
5439 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5440 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5443 arg2
= force_rvalue (arg2
, complain
);
5444 if (!CLASS_TYPE_P (arg2_type
))
5445 arg2_type
= TREE_TYPE (arg2
);
5447 arg3
= force_rvalue (arg3
, complain
);
5448 if (!CLASS_TYPE_P (arg3_type
))
5449 arg3_type
= TREE_TYPE (arg3
);
5451 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5452 return error_mark_node
;
5456 After those conversions, one of the following shall hold:
5458 --The second and third operands have the same type; the result is of
5460 if (same_type_p (arg2_type
, arg3_type
))
5461 result_type
= arg2_type
;
5464 --The second and third operands have arithmetic or enumeration
5465 type; the usual arithmetic conversions are performed to bring
5466 them to a common type, and the result is of that type. */
5467 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5468 || UNSCOPED_ENUM_P (arg2_type
))
5469 && (ARITHMETIC_TYPE_P (arg3_type
)
5470 || UNSCOPED_ENUM_P (arg3_type
)))
5472 /* In this case, there is always a common type. */
5473 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5475 if (complain
& tf_warning
)
5476 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5477 "implicit conversion from %qH to %qI to "
5478 "match other result of conditional",
5481 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5482 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5484 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5485 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5486 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5487 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5488 && (DECL_CONTEXT (stripped_orig_arg2
)
5489 == DECL_CONTEXT (stripped_orig_arg3
)))
5490 /* Two enumerators from the same enumeration can have different
5491 types when the enumeration is still being defined. */;
5492 else if (complain
& tf_warning
)
5493 warning_at (loc
, OPT_Wenum_compare
, "enumerated mismatch "
5494 "in conditional expression: %qT vs %qT",
5495 arg2_type
, arg3_type
);
5497 else if (extra_warnings
5498 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5499 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5500 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5501 && !same_type_p (arg2_type
,
5502 type_promotes_to (arg3_type
)))))
5504 if (complain
& tf_warning
)
5505 warning_at (loc
, OPT_Wextra
, "enumerated and non-enumerated "
5506 "type in conditional expression");
5509 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5510 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5514 --The second and third operands have pointer type, or one has
5515 pointer type and the other is a null pointer constant; pointer
5516 conversions (_conv.ptr_) and qualification conversions
5517 (_conv.qual_) are performed to bring them to their composite
5518 pointer type (_expr.rel_). The result is of the composite
5521 --The second and third operands have pointer to member type, or
5522 one has pointer to member type and the other is a null pointer
5523 constant; pointer to member conversions (_conv.mem_) and
5524 qualification conversions (_conv.qual_) are performed to bring
5525 them to a common type, whose cv-qualification shall match the
5526 cv-qualification of either the second or the third operand.
5527 The result is of the common type. */
5528 else if ((null_ptr_cst_p (arg2
)
5529 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5530 || (null_ptr_cst_p (arg3
)
5531 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5532 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5533 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5534 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5536 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5537 arg3
, CPO_CONDITIONAL_EXPR
,
5539 if (result_type
== error_mark_node
)
5540 return error_mark_node
;
5541 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5542 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5547 if (complain
& tf_error
)
5548 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5549 arg2_type
, arg3_type
);
5550 return error_mark_node
;
5553 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5554 return error_mark_node
;
5557 if (processing_template_decl
&& is_glvalue
)
5559 /* Let lvalue_kind know this was a glvalue. */
5560 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5561 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5564 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5566 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5567 warn here, because the COND_EXPR will be turned into ARG2. */
5568 if (warn_duplicated_branches
5569 && (complain
& tf_warning
)
5570 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5571 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5572 "this condition has identical branches");
5574 /* We can't use result_type below, as fold might have returned a
5579 /* Expand both sides into the same slot, hopefully the target of
5580 the ?: expression. We used to check for TARGET_EXPRs here,
5581 but now we sometimes wrap them in NOP_EXPRs so the test would
5583 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5584 result
= get_target_expr_sfinae (result
, complain
);
5585 /* If this expression is an rvalue, but might be mistaken for an
5586 lvalue, we must add a NON_LVALUE_EXPR. */
5587 result
= rvalue (result
);
5590 result
= force_paren_expr (result
);
5595 /* Wrapper for above. */
5598 build_conditional_expr (const op_location_t
&loc
,
5599 tree arg1
, tree arg2
, tree arg3
,
5600 tsubst_flags_t complain
)
5603 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5604 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5605 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5609 /* OPERAND is an operand to an expression. Perform necessary steps
5610 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5614 prep_operand (tree operand
)
5618 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5619 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5620 /* Make sure the template type is instantiated now. */
5621 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5627 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5628 OVERLOAD) to the CANDIDATES, returning an updated list of
5629 CANDIDATES. The ARGS are the arguments provided to the call;
5630 if FIRST_ARG is non-null it is the implicit object argument,
5631 otherwise the first element of ARGS is used if needed. The
5632 EXPLICIT_TARGS are explicit template arguments provided.
5633 TEMPLATE_ONLY is true if only template functions should be
5634 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5635 add_function_candidate. */
5638 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5640 tree explicit_targs
, bool template_only
,
5641 tree conversion_path
, tree access_path
,
5643 struct z_candidate
**candidates
,
5644 tsubst_flags_t complain
)
5647 const vec
<tree
, va_gc
> *non_static_args
;
5648 bool check_list_ctor
= false;
5649 bool check_converting
= false;
5650 unification_kind_t strict
;
5655 /* Precalculate special handling of constructors and conversion ops. */
5656 tree fn
= OVL_FIRST (fns
);
5657 if (DECL_CONV_FN_P (fn
))
5659 check_list_ctor
= false;
5660 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5661 if (flags
& LOOKUP_NO_CONVERSION
)
5662 /* We're doing return_type(x). */
5663 strict
= DEDUCE_CONV
;
5665 /* We're doing x.operator return_type(). */
5666 strict
= DEDUCE_EXACT
;
5667 /* [over.match.funcs] For conversion functions, the function
5668 is considered to be a member of the class of the implicit
5669 object argument for the purpose of defining the type of
5670 the implicit object parameter. */
5671 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5675 if (DECL_CONSTRUCTOR_P (fn
))
5677 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5678 /* For list-initialization we consider explicit constructors
5679 and complain if one is chosen. */
5681 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5682 == LOOKUP_ONLYCONVERTING
);
5684 strict
= DEDUCE_CALL
;
5685 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5689 non_static_args
= args
;
5691 /* Delay creating the implicit this parameter until it is needed. */
5692 non_static_args
= NULL
;
5694 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5698 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5700 if (check_list_ctor
&& !is_list_ctor (fn
))
5703 tree fn_first_arg
= NULL_TREE
;
5704 const vec
<tree
, va_gc
> *fn_args
= args
;
5706 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5708 /* Figure out where the object arg comes from. If this
5709 function is a non-static member and we didn't get an
5710 implicit object argument, move it out of args. */
5711 if (first_arg
== NULL_TREE
)
5715 vec
<tree
, va_gc
> *tempvec
;
5716 vec_alloc (tempvec
, args
->length () - 1);
5717 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5718 tempvec
->quick_push (arg
);
5719 non_static_args
= tempvec
;
5720 first_arg
= (*args
)[0];
5723 fn_first_arg
= first_arg
;
5724 fn_args
= non_static_args
;
5727 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5728 add_template_candidate (candidates
,
5740 else if (!template_only
)
5741 add_function_candidate (candidates
,
5754 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5755 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5758 op_is_ordered (tree_code code
)
5764 return (flag_strong_eval_order
> 1 ? -1 : 0);
5768 return (flag_strong_eval_order
> 1 ? 1 : 0);
5771 // Not overloadable (yet).
5773 // Only one argument.
5780 return (flag_strong_eval_order
? 1 : 0);
5788 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5789 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5790 tsubst_flags_t complain
)
5792 struct z_candidate
*candidates
= 0, *cand
;
5793 vec
<tree
, va_gc
> *arglist
;
5795 tree result
= NULL_TREE
;
5796 bool result_valid_p
= false;
5797 enum tree_code code2
= NOP_EXPR
;
5798 enum tree_code code_orig_arg1
= ERROR_MARK
;
5799 enum tree_code code_orig_arg2
= ERROR_MARK
;
5805 if (error_operand_p (arg1
)
5806 || error_operand_p (arg2
)
5807 || error_operand_p (arg3
))
5808 return error_mark_node
;
5810 bool ismodop
= code
== MODIFY_EXPR
;
5813 code2
= TREE_CODE (arg3
);
5816 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5818 tree arg1_type
= unlowered_expr_type (arg1
);
5819 tree arg2_type
= arg2
? unlowered_expr_type (arg2
) : NULL_TREE
;
5821 arg1
= prep_operand (arg1
);
5823 bool memonly
= false;
5828 case VEC_DELETE_EXPR
:
5830 /* Use build_op_new_call and build_op_delete_call instead. */
5834 /* Use build_op_call instead. */
5837 case TRUTH_ORIF_EXPR
:
5838 case TRUTH_ANDIF_EXPR
:
5839 case TRUTH_AND_EXPR
:
5841 /* These are saved for the sake of warn_logical_operator. */
5842 code_orig_arg1
= TREE_CODE (arg1
);
5843 code_orig_arg2
= TREE_CODE (arg2
);
5851 /* These are saved for the sake of maybe_warn_bool_compare. */
5852 code_orig_arg1
= TREE_CODE (arg1_type
);
5853 code_orig_arg2
= TREE_CODE (arg2_type
);
5856 /* =, ->, [], () must be non-static member functions. */
5858 if (code2
!= NOP_EXPR
)
5870 arg2
= prep_operand (arg2
);
5871 arg3
= prep_operand (arg3
);
5873 if (code
== COND_EXPR
)
5874 /* Use build_conditional_expr instead. */
5876 else if (! OVERLOAD_TYPE_P (arg1_type
)
5877 && (! arg2
|| ! OVERLOAD_TYPE_P (arg2_type
)))
5880 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5882 arg2
= integer_zero_node
;
5883 arg2_type
= integer_type_node
;
5886 vec_alloc (arglist
, 3);
5887 arglist
->quick_push (arg1
);
5888 if (arg2
!= NULL_TREE
)
5889 arglist
->quick_push (arg2
);
5890 if (arg3
!= NULL_TREE
)
5891 arglist
->quick_push (arg3
);
5893 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5894 p
= conversion_obstack_alloc (0);
5896 /* Add namespace-scope operators to the list of functions to
5900 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5901 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5902 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5903 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5904 flags
, &candidates
, complain
);
5909 args
[2] = NULL_TREE
;
5911 /* Add class-member operators to the candidate set. */
5912 if (CLASS_TYPE_P (arg1_type
))
5916 fns
= lookup_fnfields (arg1_type
, fnname
, 1);
5917 if (fns
== error_mark_node
)
5919 result
= error_mark_node
;
5920 goto user_defined_result_ready
;
5923 add_candidates (BASELINK_FUNCTIONS (fns
),
5924 NULL_TREE
, arglist
, NULL_TREE
,
5926 BASELINK_BINFO (fns
),
5927 BASELINK_ACCESS_BINFO (fns
),
5928 flags
, &candidates
, complain
);
5930 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5931 only non-member functions that have type T1 or reference to
5932 cv-qualified-opt T1 for the first argument, if the first argument
5933 has an enumeration type, or T2 or reference to cv-qualified-opt
5934 T2 for the second argument, if the second argument has an
5935 enumeration type. Filter out those that don't match. */
5936 else if (! arg2
|| ! CLASS_TYPE_P (arg2_type
))
5938 struct z_candidate
**candp
, **next
;
5940 for (candp
= &candidates
; *candp
; candp
= next
)
5942 tree parmlist
, parmtype
;
5943 int i
, nargs
= (arg2
? 2 : 1);
5948 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5950 for (i
= 0; i
< nargs
; ++i
)
5952 parmtype
= TREE_VALUE (parmlist
);
5954 if (TYPE_REF_P (parmtype
))
5955 parmtype
= TREE_TYPE (parmtype
);
5956 if (TREE_CODE (unlowered_expr_type (args
[i
])) == ENUMERAL_TYPE
5957 && (same_type_ignoring_top_level_qualifiers_p
5958 (unlowered_expr_type (args
[i
]), parmtype
)))
5961 parmlist
= TREE_CHAIN (parmlist
);
5964 /* No argument has an appropriate type, so remove this
5965 candidate function from the list. */
5968 *candp
= cand
->next
;
5974 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5981 /* For these, the built-in candidates set is empty
5982 [over.match.oper]/3. We don't want non-strict matches
5983 because exact matches are always possible with built-in
5984 operators. The built-in candidate set for COMPONENT_REF
5985 would be empty too, but since there are no such built-in
5986 operators, we accept non-strict matches for them. */
5995 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
6000 case POSTINCREMENT_EXPR
:
6001 case POSTDECREMENT_EXPR
:
6002 /* Don't try anything fancy if we're not allowed to produce
6004 if (!(complain
& tf_error
))
6005 return error_mark_node
;
6007 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
6008 distinguish between prefix and postfix ++ and
6009 operator++() was used for both, so we allow this with
6013 const char *msg
= (flag_permissive
)
6014 ? G_("no %<%D(int)%> declared for postfix %qs,"
6015 " trying prefix operator instead")
6016 : G_("no %<%D(int)%> declared for postfix %qs");
6017 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
6020 if (!flag_permissive
)
6021 return error_mark_node
;
6023 if (code
== POSTINCREMENT_EXPR
)
6024 code
= PREINCREMENT_EXPR
;
6026 code
= PREDECREMENT_EXPR
;
6027 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
6028 NULL_TREE
, overload
, complain
);
6031 /* The caller will deal with these. */
6036 result_valid_p
= true;
6040 if (complain
& tf_error
)
6042 /* If one of the arguments of the operator represents
6043 an invalid use of member function pointer, try to report
6044 a meaningful error ... */
6045 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
6046 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
6047 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
6048 /* We displayed the error message. */;
6051 /* ... Otherwise, report the more generic
6052 "no matching operator found" error */
6053 auto_diagnostic_group d
;
6054 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
6055 print_z_candidates (loc
, candidates
);
6058 result
= error_mark_node
;
6064 cand
= tourney (candidates
, complain
);
6067 if (complain
& tf_error
)
6069 auto_diagnostic_group d
;
6070 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
6071 print_z_candidates (loc
, candidates
);
6073 result
= error_mark_node
;
6075 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
6078 *overload
= cand
->fn
;
6080 if (resolve_args (arglist
, complain
) == NULL
)
6081 result
= error_mark_node
;
6083 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6085 if (trivial_fn_p (cand
->fn
))
6086 /* There won't be a CALL_EXPR. */;
6087 else if (result
&& result
!= error_mark_node
)
6089 tree call
= extract_call_expr (result
);
6090 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
6092 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
6093 /* This prevents build_new_function_call from discarding this
6094 function during instantiation of the enclosing template. */
6095 KOENIG_LOOKUP_P (call
) = 1;
6097 /* Specify evaluation order as per P0145R2. */
6098 CALL_EXPR_ORDERED_ARGS (call
) = false;
6099 switch (op_is_ordered (code
))
6102 CALL_EXPR_REVERSE_ARGS (call
) = true;
6106 CALL_EXPR_ORDERED_ARGS (call
) = true;
6116 /* Give any warnings we noticed during overload resolution. */
6117 if (cand
->warnings
&& (complain
& tf_warning
))
6119 struct candidate_warning
*w
;
6120 for (w
= cand
->warnings
; w
; w
= w
->next
)
6121 joust (cand
, w
->loser
, 1, complain
);
6124 /* Check for comparison of different enum types. */
6133 if (TREE_CODE (arg1_type
) == ENUMERAL_TYPE
6134 && TREE_CODE (arg2_type
) == ENUMERAL_TYPE
6135 && (TYPE_MAIN_VARIANT (arg1_type
)
6136 != TYPE_MAIN_VARIANT (arg2_type
))
6137 && (complain
& tf_warning
))
6139 warning (OPT_Wenum_compare
,
6140 "comparison between %q#T and %q#T",
6141 arg1_type
, arg2_type
);
6148 /* We need to strip any leading REF_BIND so that bitfields
6149 don't cause errors. This should not remove any important
6150 conversions, because builtins don't apply to class
6151 objects directly. */
6152 conv
= cand
->convs
[0];
6153 if (conv
->kind
== ck_ref_bind
)
6154 conv
= next_conversion (conv
);
6155 arg1
= convert_like (conv
, arg1
, complain
);
6159 conv
= cand
->convs
[1];
6160 if (conv
->kind
== ck_ref_bind
)
6161 conv
= next_conversion (conv
);
6163 arg2
= decay_conversion (arg2
, complain
);
6165 /* We need to call warn_logical_operator before
6166 converting arg2 to a boolean_type, but after
6167 decaying an enumerator to its value. */
6168 if (complain
& tf_warning
)
6169 warn_logical_operator (loc
, code
, boolean_type_node
,
6170 code_orig_arg1
, arg1
,
6171 code_orig_arg2
, arg2
);
6173 arg2
= convert_like (conv
, arg2
, complain
);
6177 conv
= cand
->convs
[2];
6178 if (conv
->kind
== ck_ref_bind
)
6179 conv
= next_conversion (conv
);
6180 convert_like (conv
, arg3
, complain
);
6186 user_defined_result_ready
:
6188 /* Free all the conversions we allocated. */
6189 obstack_free (&conversion_obstack
, p
);
6191 if (result
|| result_valid_p
)
6198 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6201 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6203 case TRUTH_ANDIF_EXPR
:
6204 case TRUTH_ORIF_EXPR
:
6205 case TRUTH_AND_EXPR
:
6207 if (complain
& tf_warning
)
6208 warn_logical_operator (loc
, code
, boolean_type_node
,
6209 code_orig_arg1
, arg1
,
6210 code_orig_arg2
, arg2
);
6218 if ((complain
& tf_warning
)
6219 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6220 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6221 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6222 if (complain
& tf_warning
&& warn_tautological_compare
)
6223 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6228 case TRUNC_DIV_EXPR
:
6233 case TRUNC_MOD_EXPR
:
6237 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6239 case UNARY_PLUS_EXPR
:
6242 case TRUTH_NOT_EXPR
:
6243 case PREINCREMENT_EXPR
:
6244 case POSTINCREMENT_EXPR
:
6245 case PREDECREMENT_EXPR
:
6246 case POSTDECREMENT_EXPR
:
6250 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6253 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6256 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6260 /* The caller will deal with these. */
6272 /* Wrapper for above. */
6275 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6276 tree arg1
, tree arg2
, tree arg3
,
6277 tree
*overload
, tsubst_flags_t complain
)
6280 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6281 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6282 overload
, complain
);
6283 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6287 /* CALL was returned by some call-building function; extract the actual
6288 CALL_EXPR from any bits that have been tacked on, e.g. by
6289 convert_from_reference. */
6292 extract_call_expr (tree call
)
6294 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6295 call
= TREE_OPERAND (call
, 1);
6296 if (REFERENCE_REF_P (call
))
6297 call
= TREE_OPERAND (call
, 0);
6298 if (TREE_CODE (call
) == TARGET_EXPR
)
6299 call
= TARGET_EXPR_INITIAL (call
);
6300 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6301 || TREE_CODE (call
) == AGGR_INIT_EXPR
6302 || call
== error_mark_node
);
6306 /* Returns true if FN has two parameters, of which the second has type
6310 second_parm_is_size_t (tree fn
)
6312 tree t
= FUNCTION_ARG_CHAIN (fn
);
6313 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6316 if (t
== void_list_node
)
6321 /* True if T, an allocation function, has std::align_val_t as its second
6325 aligned_allocation_fn_p (tree t
)
6327 if (!aligned_new_threshold
)
6330 tree a
= FUNCTION_ARG_CHAIN (t
);
6331 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6334 /* True if T is std::destroying_delete_t. */
6337 std_destroying_delete_t_p (tree t
)
6339 return (TYPE_CONTEXT (t
) == std_node
6340 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6343 /* A deallocation function with at least two parameters whose second parameter
6344 type is of type std::destroying_delete_t is a destroying operator delete. A
6345 destroying operator delete shall be a class member function named operator
6346 delete. [ Note: Array deletion cannot use a destroying operator
6347 delete. --end note ] */
6350 destroying_delete_p (tree t
)
6352 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6353 if (!a
|| !TREE_CHAIN (a
))
6355 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6356 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6366 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6367 function (3.7.4.2 [basic.stc.dynamic.deallocation]). If so, and DI is
6368 non-null, also set *DI. */
6371 usual_deallocation_fn_p (tree t
, dealloc_info
*di
)
6373 if (di
) *di
= dealloc_info();
6375 /* A template instance is never a usual deallocation function,
6376 regardless of its signature. */
6377 if (TREE_CODE (t
) == TEMPLATE_DECL
6378 || primary_template_specialization_p (t
))
6381 /* A usual deallocation function is a deallocation function whose parameters
6383 - optionally, a parameter of type std::destroying_delete_t, then
6384 - optionally, a parameter of type std::size_t, then
6385 - optionally, a parameter of type std::align_val_t. */
6386 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6387 tree chain
= FUNCTION_ARG_CHAIN (t
);
6388 if (chain
&& destroying_delete_p (t
))
6390 if (di
) di
->destroying
= TREE_VALUE (chain
);
6391 chain
= TREE_CHAIN (chain
);
6394 && (!global
|| flag_sized_deallocation
)
6395 && same_type_p (TREE_VALUE (chain
), size_type_node
))
6397 if (di
) di
->sized
= true;
6398 chain
= TREE_CHAIN (chain
);
6400 if (chain
&& aligned_new_threshold
6401 && same_type_p (TREE_VALUE (chain
), align_type_node
))
6403 if (di
) di
->aligned
= true;
6404 chain
= TREE_CHAIN (chain
);
6406 return (chain
== void_list_node
);
6409 /* Just return whether FN is a usual deallocation function. */
6412 usual_deallocation_fn_p (tree fn
)
6414 return usual_deallocation_fn_p (fn
, NULL
);
6417 /* Build a call to operator delete. This has to be handled very specially,
6418 because the restrictions on what signatures match are different from all
6419 other call instances. For a normal delete, only a delete taking (void *)
6420 or (void *, size_t) is accepted. For a placement delete, only an exact
6421 match with the placement new is accepted.
6423 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6424 ADDR is the pointer to be deleted.
6425 SIZE is the size of the memory block to be deleted.
6426 GLOBAL_P is true if the delete-expression should not consider
6427 class-specific delete operators.
6428 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6430 If this call to "operator delete" is being generated as part to
6431 deallocate memory allocated via a new-expression (as per [expr.new]
6432 which requires that if the initialization throws an exception then
6433 we call a deallocation function), then ALLOC_FN is the allocation
6437 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6438 bool global_p
, tree placement
,
6439 tree alloc_fn
, tsubst_flags_t complain
)
6441 tree fn
= NULL_TREE
;
6442 tree fns
, fnname
, type
, t
;
6443 dealloc_info di_fn
= { };
6445 if (addr
== error_mark_node
)
6446 return error_mark_node
;
6448 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6450 fnname
= ovl_op_identifier (false, code
);
6452 if (CLASS_TYPE_P (type
)
6453 && COMPLETE_TYPE_P (complete_type (type
))
6457 If the result of the lookup is ambiguous or inaccessible, or if
6458 the lookup selects a placement deallocation function, the
6459 program is ill-formed.
6461 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6463 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6464 if (fns
== error_mark_node
)
6465 return error_mark_node
;
6470 if (fns
== NULL_TREE
)
6471 fns
= lookup_name_nonclass (fnname
);
6473 /* Strip const and volatile from addr. */
6475 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6479 /* "A declaration of a placement deallocation function matches the
6480 declaration of a placement allocation function if it has the same
6481 number of parameters and, after parameter transformations (8.3.5),
6482 all parameter types except the first are identical."
6484 So we build up the function type we want and ask instantiate_type
6485 to get it for us. */
6486 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6487 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6488 t
= build_function_type (void_type_node
, t
);
6490 fn
= instantiate_type (t
, fns
, tf_none
);
6491 if (fn
== error_mark_node
)
6494 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6496 /* "If the lookup finds the two-parameter form of a usual deallocation
6497 function (3.7.4.2) and that function, considered as a placement
6498 deallocation function, would have been selected as a match for the
6499 allocation function, the program is ill-formed." */
6500 if (second_parm_is_size_t (fn
))
6502 const char *const msg1
6503 = G_("exception cleanup for this placement new selects "
6504 "non-placement %<operator delete%>");
6505 const char *const msg2
6506 = G_("%qD is a usual (non-placement) deallocation "
6507 "function in C++14 (or with %<-fsized-deallocation%>)");
6509 /* But if the class has an operator delete (void *), then that is
6510 the usual deallocation function, so we shouldn't complain
6511 about using the operator delete (void *, size_t). */
6512 if (DECL_CLASS_SCOPE_P (fn
))
6513 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6517 if (usual_deallocation_fn_p (elt
)
6518 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6521 /* Before C++14 a two-parameter global deallocation function is
6522 always a placement deallocation function, but warn if
6524 else if (!flag_sized_deallocation
)
6526 if (complain
& tf_warning
)
6528 auto_diagnostic_group d
;
6529 if (warning (OPT_Wc__14_compat
, msg1
))
6530 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6535 if (complain
& tf_warning_or_error
)
6537 auto_diagnostic_group d
;
6538 if (permerror (input_location
, msg1
))
6540 /* Only mention C++14 for namespace-scope delete. */
6541 if (DECL_NAMESPACE_SCOPE_P (fn
))
6542 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6544 inform (DECL_SOURCE_LOCATION (fn
),
6545 "%qD is a usual (non-placement) deallocation "
6550 return error_mark_node
;
6555 /* "Any non-placement deallocation function matches a non-placement
6556 allocation function. If the lookup finds a single matching
6557 deallocation function, that function will be called; otherwise, no
6558 deallocation function will be called." */
6559 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6562 dealloc_info di_elt
;
6563 if (usual_deallocation_fn_p (elt
, &di_elt
))
6572 /* -- If any of the deallocation functions is a destroying
6573 operator delete, all deallocation functions that are not
6574 destroying operator deletes are eliminated from further
6576 if (di_elt
.destroying
!= di_fn
.destroying
)
6578 if (di_elt
.destroying
)
6586 /* -- If the type has new-extended alignment, a function with a
6587 parameter of type std::align_val_t is preferred; otherwise a
6588 function without such a parameter is preferred. If exactly one
6589 preferred function is found, that function is selected and the
6590 selection process terminates. If more than one preferred
6591 function is found, all non-preferred functions are eliminated
6592 from further consideration. */
6593 if (aligned_new_threshold
)
6595 bool want_align
= type_has_new_extended_alignment (type
);
6596 if (di_elt
.aligned
!= di_fn
.aligned
)
6598 if (want_align
== di_elt
.aligned
)
6607 /* -- If the deallocation functions have class scope, the one
6608 without a parameter of type std::size_t is selected. */
6610 if (DECL_CLASS_SCOPE_P (fn
))
6613 /* -- If the type is complete and if, for the second alternative
6614 (delete array) only, the operand is a pointer to a class type
6615 with a non-trivial destructor or a (possibly multi-dimensional)
6616 array thereof, the function with a parameter of type std::size_t
6619 -- Otherwise, it is unspecified whether a deallocation function
6620 with a parameter of type std::size_t is selected. */
6623 want_size
= COMPLETE_TYPE_P (type
);
6624 if (code
== VEC_DELETE_EXPR
6625 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6626 /* We need a cookie to determine the array size. */
6629 gcc_assert (di_fn
.sized
!= di_elt
.sized
);
6630 if (want_size
== di_elt
.sized
)
6638 /* If we have a matching function, call it. */
6641 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6643 /* If the FN is a member function, make sure that it is
6645 if (BASELINK_P (fns
))
6646 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6649 /* Core issue 901: It's ok to new a type with deleted delete. */
6650 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6655 /* The placement args might not be suitable for overload
6656 resolution at this point, so build the call directly. */
6657 int nargs
= call_expr_nargs (placement
);
6658 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6661 for (i
= 1; i
< nargs
; i
++)
6662 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6663 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6664 return error_mark_node
;
6665 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6669 tree destroying
= di_fn
.destroying
;
6672 /* Strip const and volatile from addr but retain the type of the
6674 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6675 rtype
= cv_unqualified (rtype
);
6676 rtype
= TYPE_POINTER_TO (rtype
);
6677 addr
= cp_convert (rtype
, oaddr
, complain
);
6678 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6684 args
->quick_push (addr
);
6686 args
->quick_push (destroying
);
6688 args
->quick_push (size
);
6691 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6692 args
->quick_push (al
);
6694 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6701 If no unambiguous matching deallocation function can be found,
6702 propagating the exception does not cause the object's memory to
6706 if ((complain
& tf_warning
)
6708 warning (0, "no corresponding deallocation function for %qD",
6713 if (complain
& tf_error
)
6714 error ("no suitable %<operator %s%> for %qT",
6715 OVL_OP_INFO (false, code
)->name
, type
);
6716 return error_mark_node
;
6719 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6722 If ISSUE_ERROR is true, then issue an error about the
6723 access, followed by a note showing the declaration.
6724 Otherwise, just show the note. */
6727 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6729 if (TREE_PRIVATE (decl
))
6732 error ("%q#D is private within this context", diag_decl
);
6733 inform (DECL_SOURCE_LOCATION (diag_decl
),
6734 "declared private here");
6736 else if (TREE_PROTECTED (decl
))
6739 error ("%q#D is protected within this context", diag_decl
);
6740 inform (DECL_SOURCE_LOCATION (diag_decl
),
6741 "declared protected here");
6746 error ("%q#D is inaccessible within this context", diag_decl
);
6747 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6751 /* If the current scope isn't allowed to access DECL along
6752 BASETYPE_PATH, give an error. The most derived class in
6753 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6754 the declaration to use in the error diagnostic. */
6757 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6758 tsubst_flags_t complain
, access_failure_info
*afi
)
6760 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6762 if (flag_new_inheriting_ctors
6763 && DECL_INHERITED_CTOR (decl
))
6765 /* 7.3.3/18: The additional constructors are accessible if they would be
6766 accessible when used to construct an object of the corresponding base
6768 decl
= strip_inheriting_ctors (decl
);
6769 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6770 ba_any
, NULL
, complain
);
6773 if (!accessible_p (basetype_path
, decl
, true))
6775 if (flag_new_inheriting_ctors
)
6776 diag_decl
= strip_inheriting_ctors (diag_decl
);
6777 if (complain
& tf_error
)
6778 complain_about_access (decl
, diag_decl
, true);
6780 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6787 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6788 bitwise or of LOOKUP_* values. If any errors are warnings are
6789 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6790 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6794 build_temp (tree expr
, tree type
, int flags
,
6795 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6799 *diagnostic_kind
= DK_UNSPECIFIED
;
6801 /* If the source is a packed field, calling the copy constructor will require
6802 binding the field to the reference parameter to the copy constructor, and
6803 we'll end up with an infinite loop. If we can use a bitwise copy, then
6805 if ((lvalue_kind (expr
) & clk_packed
)
6806 && CLASS_TYPE_P (TREE_TYPE (expr
))
6807 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6808 return get_target_expr_sfinae (expr
, complain
);
6810 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6811 releasing_vec
args (make_tree_vector_single (expr
));
6812 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6813 &args
, type
, flags
, complain
);
6814 if (warningcount
+ werrorcount
> savew
)
6815 *diagnostic_kind
= DK_WARNING
;
6816 else if (errorcount
> savee
)
6817 *diagnostic_kind
= DK_ERROR
;
6821 /* Get any location for EXPR, falling back to input_location.
6823 If the result is in a system header and is the virtual location for
6824 a token coming from the expansion of a macro, unwind it to the
6825 location of the expansion point of the macro (e.g. to avoid the
6826 diagnostic being suppressed for expansions of NULL where "NULL" is
6827 in a system header). */
6830 get_location_for_expr_unwinding_for_system_header (tree expr
)
6832 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6833 loc
= expansion_point_location_if_in_system_header (loc
);
6837 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6838 Also handle a subset of zero as null warnings.
6839 EXPR is implicitly converted to type TOTYPE.
6840 FN and ARGNUM are used for diagnostics. */
6843 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6845 /* Issue warnings about peculiar, but valid, uses of NULL. */
6846 if (TREE_CODE (totype
) != BOOLEAN_TYPE
6847 && ARITHMETIC_TYPE_P (totype
)
6848 && null_node_p (expr
))
6850 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6853 auto_diagnostic_group d
;
6854 if (warning_at (loc
, OPT_Wconversion_null
,
6855 "passing NULL to non-pointer argument %P of %qD",
6857 inform (get_fndecl_argument_location (fn
, argnum
),
6861 warning_at (loc
, OPT_Wconversion_null
,
6862 "converting to non-pointer type %qT from NULL", totype
);
6865 /* Issue warnings if "false" is converted to a NULL pointer */
6866 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6867 && TYPE_PTR_P (totype
))
6869 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6872 auto_diagnostic_group d
;
6873 if (warning_at (loc
, OPT_Wconversion_null
,
6874 "converting %<false%> to pointer type for argument "
6875 "%P of %qD", argnum
, fn
))
6876 inform (get_fndecl_argument_location (fn
, argnum
),
6880 warning_at (loc
, OPT_Wconversion_null
,
6881 "converting %<false%> to pointer type %qT", totype
);
6883 /* Handle zero as null pointer warnings for cases other
6884 than EQ_EXPR and NE_EXPR */
6885 else if ((TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
))
6886 && null_ptr_cst_p (expr
))
6888 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6889 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6893 /* We gave a diagnostic during a conversion. If this was in the second
6894 standard conversion sequence of a user-defined conversion sequence, say
6895 which user-defined conversion. */
6898 maybe_print_user_conv_context (conversion
*convs
)
6900 if (convs
->user_conv_p
)
6901 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6902 if (t
->kind
== ck_user
)
6904 print_z_candidate (0, N_(" after user-defined conversion:"),
6910 /* Locate the parameter with the given index within FNDECL.
6911 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6912 Return the location of the FNDECL itself if there are problems. */
6915 get_fndecl_argument_location (tree fndecl
, int argnum
)
6917 /* The locations of implicitly-declared functions are likely to be
6918 more meaningful than those of their parameters. */
6919 if (DECL_ARTIFICIAL (fndecl
))
6920 return DECL_SOURCE_LOCATION (fndecl
);
6925 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6926 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6927 i
< argnum
&& param
;
6928 i
++, param
= TREE_CHAIN (param
))
6931 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6932 return the location of FNDECL. */
6934 return DECL_SOURCE_LOCATION (fndecl
);
6936 return DECL_SOURCE_LOCATION (param
);
6939 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6940 within its declaration (or the fndecl itself if something went
6944 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6947 inform (get_fndecl_argument_location (fn
, argnum
),
6948 " initializing argument %P of %qD", argnum
, fn
);
6951 /* Perform the conversions in CONVS on the expression EXPR. FN and
6952 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6953 indicates the `this' argument of a method. INNER is nonzero when
6954 being called to continue a conversion chain. It is negative when a
6955 reference binding will be applied, positive otherwise. If
6956 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6957 conversions will be emitted if appropriate. If C_CAST_P is true,
6958 this conversion is coming from a C-style cast; in that case,
6959 conversions to inaccessible bases are permitted. */
6962 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6963 bool issue_conversion_warnings
,
6964 bool c_cast_p
, tsubst_flags_t complain
)
6966 tree totype
= convs
->type
;
6967 diagnostic_t diag_kind
;
6969 location_t loc
= cp_expr_loc_or_input_loc (expr
);
6971 if (convs
->bad_p
&& !(complain
& tf_error
))
6972 return error_mark_node
;
6975 && convs
->kind
!= ck_user
6976 && convs
->kind
!= ck_list
6977 && convs
->kind
!= ck_ambig
6978 && (convs
->kind
!= ck_ref_bind
6979 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6980 && (convs
->kind
!= ck_rvalue
6981 || SCALAR_TYPE_P (totype
))
6982 && convs
->kind
!= ck_base
)
6984 bool complained
= false;
6985 conversion
*t
= convs
;
6987 /* Give a helpful error if this is bad because of excess braces. */
6988 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6989 && SCALAR_TYPE_P (totype
)
6990 && CONSTRUCTOR_NELTS (expr
) > 0
6991 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6993 complained
= permerror (loc
, "too many braces around initializer "
6995 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6996 && CONSTRUCTOR_NELTS (expr
) == 1)
6997 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7000 /* Give a helpful error if this is bad because a conversion to bool
7001 from std::nullptr_t requires direct-initialization. */
7002 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
7003 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
7004 complained
= permerror (loc
, "converting to %qH from %qI requires "
7005 "direct-initialization",
7006 totype
, TREE_TYPE (expr
));
7008 for (; t
; t
= next_conversion (t
))
7010 if (t
->kind
== ck_user
&& t
->cand
->reason
)
7012 auto_diagnostic_group d
;
7013 complained
= permerror (loc
, "invalid user-defined conversion "
7014 "from %qH to %qI", TREE_TYPE (expr
),
7017 print_z_candidate (loc
, N_("candidate is:"), t
->cand
);
7018 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7019 /*issue_conversion_warnings=*/false,
7022 if (convs
->kind
== ck_ref_bind
)
7023 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
7024 LOOKUP_NORMAL
, NULL_TREE
,
7027 expr
= cp_convert (totype
, expr
, complain
);
7029 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7032 else if (t
->kind
== ck_user
|| !t
->bad_p
)
7034 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7035 /*issue_conversion_warnings=*/false,
7040 else if (t
->kind
== ck_ambig
)
7041 return convert_like_real (t
, expr
, fn
, argnum
,
7042 /*issue_conversion_warnings=*/false,
7045 else if (t
->kind
== ck_identity
)
7050 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
7051 gcc_rich_location
richloc (loc
, &label
);
7052 complained
= permerror (&richloc
,
7053 "invalid conversion from %qH to %qI",
7054 TREE_TYPE (expr
), totype
);
7057 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7059 return cp_convert (totype
, expr
, complain
);
7062 if (issue_conversion_warnings
&& (complain
& tf_warning
))
7063 conversion_null_warnings (totype
, expr
, fn
, argnum
);
7065 switch (convs
->kind
)
7069 struct z_candidate
*cand
= convs
->cand
;
7072 /* We chose the surrogate function from add_conv_candidate, now we
7073 actually need to build the conversion. */
7074 cand
= build_user_type_conversion_1 (totype
, expr
,
7075 LOOKUP_NO_CONVERSION
, complain
);
7077 tree convfn
= cand
->fn
;
7079 /* When converting from an init list we consider explicit
7080 constructors, but actually trying to call one is an error. */
7081 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
7082 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
7083 /* Unless this is for direct-list-initialization. */
7084 && (!CONSTRUCTOR_IS_DIRECT_INIT (expr
) || convs
->need_temporary_p
)
7085 /* And in C++98 a default constructor can't be explicit. */
7086 && cxx_dialect
>= cxx11
)
7088 if (!(complain
& tf_error
))
7089 return error_mark_node
;
7090 location_t loc
= location_of (expr
);
7091 if (CONSTRUCTOR_NELTS (expr
) == 0
7092 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
7094 auto_diagnostic_group d
;
7095 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
7096 "would use explicit constructor %qD",
7098 inform (loc
, "in C++11 and above a default constructor "
7102 error ("converting to %qT from initializer list would use "
7103 "explicit constructor %qD", totype
, convfn
);
7106 /* If we're initializing from {}, it's value-initialization. */
7107 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7108 && CONSTRUCTOR_NELTS (expr
) == 0
7109 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
)
7110 && !processing_template_decl
)
7112 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
7113 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
7114 return error_mark_node
;
7115 expr
= build_value_init (totype
, complain
);
7116 expr
= get_target_expr_sfinae (expr
, complain
);
7117 if (expr
!= error_mark_node
)
7119 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7120 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
7125 /* We don't know here whether EXPR is being used as an lvalue or
7126 rvalue, but we know it's read. */
7127 mark_exp_read (expr
);
7129 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
7131 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
7134 /* If this is a constructor or a function returning an aggr type,
7135 we need to build up a TARGET_EXPR. */
7136 if (DECL_CONSTRUCTOR_P (convfn
))
7138 expr
= build_cplus_new (totype
, expr
, complain
);
7140 /* Remember that this was list-initialization. */
7141 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
7142 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7148 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
7150 int nelts
= CONSTRUCTOR_NELTS (expr
);
7152 expr
= build_value_init (totype
, complain
);
7153 else if (nelts
== 1)
7154 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7158 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7159 /*read_p=*/true, UNKNOWN_LOCATION
,
7160 /*reject_builtin=*/true);
7162 if (type_unknown_p (expr
))
7163 expr
= instantiate_type (totype
, expr
, complain
);
7164 if (expr
== null_node
7165 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7166 /* If __null has been converted to an integer type, we do not want to
7167 continue to warn about uses of EXPR as an integer, rather than as a
7169 expr
= build_int_cst (totype
, 0);
7172 /* We leave bad_p off ck_ambig because overload resolution considers
7173 it valid, it just fails when we try to perform it. So we need to
7174 check complain here, too. */
7175 if (complain
& tf_error
)
7177 /* Call build_user_type_conversion again for the error. */
7178 int flags
= (convs
->need_temporary_p
7179 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7180 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7181 gcc_assert (seen_error ());
7182 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7184 return error_mark_node
;
7188 /* Conversion to std::initializer_list<T>. */
7189 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7190 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7195 tree val
; unsigned ix
;
7197 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7199 /* Convert all the elements. */
7200 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7202 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
,
7203 argnum
, false, false, complain
);
7204 if (sub
== error_mark_node
)
7206 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7207 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7208 return error_mark_node
;
7209 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
),
7211 if (!TREE_CONSTANT (sub
))
7212 TREE_CONSTANT (new_ctor
) = false;
7214 /* Build up the array. */
7215 elttype
= cp_build_qualified_type
7216 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7217 array
= build_array_of_n_type (elttype
, len
);
7218 array
= finish_compound_literal (array
, new_ctor
, complain
);
7219 /* Take the address explicitly rather than via decay_conversion
7220 to avoid the error about taking the address of a temporary. */
7221 array
= cp_build_addr_expr (array
, complain
);
7224 array
= nullptr_node
;
7226 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7227 if (array
== error_mark_node
)
7228 return error_mark_node
;
7230 /* Build up the initializer_list object. Note: fail gracefully
7231 if the object cannot be completed because, for example, no
7232 definition is provided (c++/80956). */
7233 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7235 return error_mark_node
;
7236 tree field
= next_initializable_field (TYPE_FIELDS (totype
));
7237 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7238 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7239 field
= next_initializable_field (DECL_CHAIN (field
));
7240 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7241 tree new_ctor
= build_constructor (totype
, vec
);
7242 return get_target_expr_sfinae (new_ctor
, complain
);
7246 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7248 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7249 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7250 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7252 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7254 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7257 expr
= reshape_init (totype
, expr
, complain
);
7258 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7260 if (expr
!= error_mark_node
)
7261 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7268 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7269 convs
->kind
== ck_ref_bind
7270 ? issue_conversion_warnings
: false,
7271 c_cast_p
, complain
);
7272 if (expr
== error_mark_node
)
7273 return error_mark_node
;
7275 switch (convs
->kind
)
7278 expr
= decay_conversion (expr
, complain
);
7279 if (expr
== error_mark_node
)
7281 if (complain
& tf_error
)
7283 auto_diagnostic_group d
;
7284 maybe_print_user_conv_context (convs
);
7285 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7287 return error_mark_node
;
7290 if (! MAYBE_CLASS_TYPE_P (totype
))
7293 /* Don't introduce copies when passing arguments along to the inherited
7295 if (current_function_decl
7296 && flag_new_inheriting_ctors
7297 && DECL_INHERITED_CTOR (current_function_decl
))
7300 if (TREE_CODE (expr
) == TARGET_EXPR
7301 && TARGET_EXPR_LIST_INIT_P (expr
))
7302 /* Copy-list-initialization doesn't actually involve a copy. */
7307 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7309 /* We are going to bind a reference directly to a base-class
7310 subobject of EXPR. */
7311 /* Build an expression for `*((base*) &expr)'. */
7312 expr
= convert_to_base (expr
, totype
,
7313 !c_cast_p
, /*nonnull=*/true, complain
);
7317 /* Copy-initialization where the cv-unqualified version of the source
7318 type is the same class as, or a derived class of, the class of the
7319 destination [is treated as direct-initialization]. [dcl.init] */
7320 flags
= LOOKUP_NORMAL
;
7321 if (convs
->user_conv_p
)
7322 /* This conversion is being done in the context of a user-defined
7323 conversion (i.e. the second step of copy-initialization), so
7324 don't allow any more. */
7325 flags
|= LOOKUP_NO_CONVERSION
;
7327 flags
|= LOOKUP_ONLYCONVERTING
;
7328 if (convs
->rvaluedness_matches_p
)
7329 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7330 flags
|= LOOKUP_PREFER_RVALUE
;
7331 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7332 if (diag_kind
&& complain
)
7334 auto_diagnostic_group d
;
7335 maybe_print_user_conv_context (convs
);
7336 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7339 return build_cplus_new (totype
, expr
, complain
);
7343 tree ref_type
= totype
;
7345 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7347 tree extype
= TREE_TYPE (expr
);
7348 auto_diagnostic_group d
;
7349 if (TYPE_REF_IS_RVALUE (ref_type
)
7351 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7352 "lvalue of type %qI", totype
, extype
);
7353 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7354 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7355 error_at (loc
, "cannot bind non-const lvalue reference of "
7356 "type %qH to an rvalue of type %qI", totype
, extype
);
7357 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7358 error_at (loc
, "binding reference of type %qH to %qI "
7359 "discards qualifiers", totype
, extype
);
7362 maybe_print_user_conv_context (convs
);
7363 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7365 return error_mark_node
;
7368 /* If necessary, create a temporary.
7370 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7371 that need temporaries, even when their types are reference
7372 compatible with the type of reference being bound, so the
7373 upcoming call to cp_build_addr_expr doesn't fail. */
7374 if (convs
->need_temporary_p
7375 || TREE_CODE (expr
) == CONSTRUCTOR
7376 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7378 /* Otherwise, a temporary of type "cv1 T1" is created and
7379 initialized from the initializer expression using the rules
7380 for a non-reference copy-initialization (8.5). */
7382 tree type
= TREE_TYPE (ref_type
);
7383 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7385 gcc_assert (similar_type_p (type
, next_conversion (convs
)->type
));
7386 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7387 && !TYPE_REF_IS_RVALUE (ref_type
))
7389 /* If the reference is volatile or non-const, we
7390 cannot create a temporary. */
7391 if (lvalue
& clk_bitfield
)
7392 error_at (loc
, "cannot bind bit-field %qE to %qT",
7394 else if (lvalue
& clk_packed
)
7395 error_at (loc
, "cannot bind packed field %qE to %qT",
7398 error_at (loc
, "cannot bind rvalue %qE to %qT",
7400 return error_mark_node
;
7402 /* If the source is a packed field, and we must use a copy
7403 constructor, then building the target expr will require
7404 binding the field to the reference parameter to the
7405 copy constructor, and we'll end up with an infinite
7406 loop. If we can use a bitwise copy, then we'll be
7408 if ((lvalue
& clk_packed
)
7409 && CLASS_TYPE_P (type
)
7410 && type_has_nontrivial_copy_init (type
))
7412 error_at (loc
, "cannot bind packed field %qE to %qT",
7414 return error_mark_node
;
7416 if (lvalue
& clk_bitfield
)
7418 expr
= convert_bitfield_to_declared_type (expr
);
7419 expr
= fold_convert (type
, expr
);
7421 expr
= build_target_expr_with_type (expr
, type
, complain
);
7424 /* Take the address of the thing to which we will bind the
7426 expr
= cp_build_addr_expr (expr
, complain
);
7427 if (expr
== error_mark_node
)
7428 return error_mark_node
;
7430 /* Convert it to a pointer to the type referred to by the
7431 reference. This will adjust the pointer if a derived to
7432 base conversion is being performed. */
7433 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7435 /* Convert the pointer to the desired reference type. */
7436 return build_nop (ref_type
, expr
);
7440 return decay_conversion (expr
, complain
);
7443 /* ??? Should the address of a transaction-safe pointer point to the TM
7444 clone, and this conversion look up the primary function? */
7445 return build_nop (totype
, expr
);
7448 /* Warn about deprecated conversion if appropriate. */
7449 if (complain
& tf_warning
)
7450 string_conv_p (totype
, expr
, 1);
7455 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7456 /*nonnull=*/false, complain
);
7457 return build_nop (totype
, expr
);
7460 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7461 c_cast_p
, complain
);
7467 if (convs
->check_narrowing
7468 && !check_narrowing (totype
, expr
, complain
,
7469 convs
->check_narrowing_const_only
))
7470 return error_mark_node
;
7472 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7473 if (issue_conversion_warnings
)
7474 expr
= cp_convert_and_check (totype
, expr
, complain
);
7476 expr
= cp_convert (totype
, expr
, complain
);
7481 /* ARG is being passed to a varargs function. Perform any conversions
7482 required. Return the converted value. */
7485 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7487 tree arg_type
= TREE_TYPE (arg
);
7488 location_t loc
= cp_expr_loc_or_input_loc (arg
);
7492 If the argument has integral or enumeration type that is subject
7493 to the integral promotions (_conv.prom_), or a floating-point
7494 type that is subject to the floating-point promotion
7495 (_conv.fpprom_), the value of the argument is converted to the
7496 promoted type before the call. */
7497 if (TREE_CODE (arg_type
) == REAL_TYPE
7498 && (TYPE_PRECISION (arg_type
)
7499 < TYPE_PRECISION (double_type_node
))
7500 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7502 if ((complain
& tf_warning
)
7503 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7504 warning_at (loc
, OPT_Wdouble_promotion
,
7505 "implicit conversion from %qH to %qI when passing "
7506 "argument to function",
7507 arg_type
, double_type_node
);
7508 arg
= convert_to_real_nofold (double_type_node
, arg
);
7510 else if (NULLPTR_TYPE_P (arg_type
))
7511 arg
= null_pointer_node
;
7512 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7514 if (SCOPED_ENUM_P (arg_type
))
7516 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7518 prom
= cp_perform_integral_promotions (prom
, complain
);
7519 if (abi_version_crosses (6)
7520 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7521 && (complain
& tf_warning
))
7522 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through %<...%>"
7523 "as %qT before %<-fabi-version=6%>, %qT after",
7525 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7526 if (!abi_version_at_least (6))
7530 arg
= cp_perform_integral_promotions (arg
, complain
);
7535 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7536 standard conversions are performed. */
7537 arg
= decay_conversion (arg
, complain
);
7539 arg
= require_complete_type_sfinae (arg
, complain
);
7540 arg_type
= TREE_TYPE (arg
);
7542 if (arg
!= error_mark_node
7543 /* In a template (or ill-formed code), we can have an incomplete type
7544 even after require_complete_type_sfinae, in which case we don't know
7545 whether it has trivial copy or not. */
7546 && COMPLETE_TYPE_P (arg_type
)
7547 && !cp_unevaluated_operand
)
7549 /* [expr.call] 5.2.2/7:
7550 Passing a potentially-evaluated argument of class type (Clause 9)
7551 with a non-trivial copy constructor or a non-trivial destructor
7552 with no corresponding parameter is conditionally-supported, with
7553 implementation-defined semantics.
7555 We support it as pass-by-invisible-reference, just like a normal
7558 If the call appears in the context of a sizeof expression,
7559 it is not potentially-evaluated. */
7560 if (type_has_nontrivial_copy_init (arg_type
)
7561 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7563 arg
= force_rvalue (arg
, complain
);
7564 if (complain
& tf_warning
)
7565 warning (OPT_Wconditionally_supported
,
7566 "passing objects of non-trivially-copyable "
7567 "type %q#T through %<...%> is conditionally supported",
7569 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7571 /* Build up a real lvalue-to-rvalue conversion in case the
7572 copy constructor is trivial but not callable. */
7573 else if (CLASS_TYPE_P (arg_type
))
7574 force_rvalue (arg
, complain
);
7581 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7584 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7586 if (processing_template_decl
)
7588 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7589 SET_EXPR_LOCATION (r
, loc
);
7593 type
= complete_type_or_else (type
, NULL_TREE
);
7595 if (expr
== error_mark_node
|| !type
)
7596 return error_mark_node
;
7598 expr
= mark_lvalue_use (expr
);
7600 if (TYPE_REF_P (type
))
7602 error ("cannot receive reference type %qT through %<...%>", type
);
7603 return error_mark_node
;
7606 if (type_has_nontrivial_copy_init (type
)
7607 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7609 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7610 it as pass by invisible reference. */
7611 warning_at (loc
, OPT_Wconditionally_supported
,
7612 "receiving objects of non-trivially-copyable type %q#T "
7613 "through %<...%> is conditionally-supported", type
);
7615 tree ref
= cp_build_reference_type (type
, false);
7616 expr
= build_va_arg (loc
, expr
, ref
);
7617 return convert_from_reference (expr
);
7620 tree ret
= build_va_arg (loc
, expr
, type
);
7621 if (CLASS_TYPE_P (type
))
7622 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7623 know how to handle it. */
7624 ret
= get_target_expr (ret
);
7628 /* TYPE has been given to va_arg. Apply the default conversions which
7629 would have happened when passed via ellipsis. Return the promoted
7630 type, or the passed type if there is no change. */
7633 cxx_type_promotes_to (tree type
)
7637 /* Perform the array-to-pointer and function-to-pointer
7639 type
= type_decays_to (type
);
7641 promote
= type_promotes_to (type
);
7642 if (same_type_p (type
, promote
))
7648 /* ARG is a default argument expression being passed to a parameter of
7649 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7650 zero-based argument number. Do any required conversions. Return
7651 the converted value. */
7653 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7655 push_defarg_context (tree fn
)
7656 { vec_safe_push (default_arg_context
, fn
); }
7659 pop_defarg_context (void)
7660 { default_arg_context
->pop (); }
7663 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7664 tsubst_flags_t complain
)
7669 /* See through clones. */
7670 fn
= DECL_ORIGIN (fn
);
7671 /* And inheriting ctors. */
7672 if (flag_new_inheriting_ctors
)
7673 fn
= strip_inheriting_ctors (fn
);
7675 /* Detect recursion. */
7676 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7679 if (complain
& tf_error
)
7680 error ("recursive evaluation of default argument for %q#D", fn
);
7681 return error_mark_node
;
7684 /* If the ARG is an unparsed default argument expression, the
7685 conversion cannot be performed. */
7686 if (TREE_CODE (arg
) == DEFERRED_PARSE
)
7688 if (complain
& tf_error
)
7689 error ("call to %qD uses the default argument for parameter %P, which "
7690 "is not yet defined", fn
, parmnum
);
7691 return error_mark_node
;
7694 push_defarg_context (fn
);
7696 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7697 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7703 The names in the expression are bound, and the semantic
7704 constraints are checked, at the point where the default
7705 expressions appears.
7707 we must not perform access checks here. */
7708 push_deferring_access_checks (dk_no_check
);
7709 /* We must make a copy of ARG, in case subsequent processing
7710 alters any part of it. */
7711 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7713 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7714 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7716 arg
= convert_for_arg_passing (type
, arg
, complain
);
7717 pop_deferring_access_checks();
7719 pop_defarg_context ();
7724 /* Returns the type which will really be used for passing an argument of
7728 type_passed_as (tree type
)
7730 /* Pass classes with copy ctors by invisible reference. */
7731 if (TREE_ADDRESSABLE (type
))
7733 type
= build_reference_type (type
);
7734 /* There are no other pointers to this temporary. */
7735 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7737 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7738 && INTEGRAL_TYPE_P (type
)
7739 && COMPLETE_TYPE_P (type
)
7740 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7741 type
= integer_type_node
;
7746 /* Actually perform the appropriate conversion. */
7749 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7753 /* If VAL is a bitfield, then -- since it has already been converted
7754 to TYPE -- it cannot have a precision greater than TYPE.
7756 If it has a smaller precision, we must widen it here. For
7757 example, passing "int f:3;" to a function expecting an "int" will
7758 not result in any conversion before this point.
7760 If the precision is the same we must not risk widening. For
7761 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7762 often have type "int", even though the C++ type for the field is
7763 "long long". If the value is being passed to a function
7764 expecting an "int", then no conversions will be required. But,
7765 if we call convert_bitfield_to_declared_type, the bitfield will
7766 be converted to "long long". */
7767 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7769 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7770 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7772 if (val
== error_mark_node
)
7774 /* Pass classes with copy ctors by invisible reference. */
7775 else if (TREE_ADDRESSABLE (type
))
7776 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7777 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7778 && INTEGRAL_TYPE_P (type
)
7779 && COMPLETE_TYPE_P (type
)
7780 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7781 val
= cp_perform_integral_promotions (val
, complain
);
7782 if (complain
& tf_warning
)
7784 if (warn_suggest_attribute_format
)
7786 tree rhstype
= TREE_TYPE (val
);
7787 const enum tree_code coder
= TREE_CODE (rhstype
);
7788 const enum tree_code codel
= TREE_CODE (type
);
7789 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7791 && check_missing_format_attribute (type
, rhstype
))
7792 warning (OPT_Wsuggest_attribute_format
,
7793 "argument of function call might be a candidate "
7794 "for a format attribute");
7796 maybe_warn_parm_abi (type
, cp_expr_loc_or_input_loc (val
));
7799 if (complain
& tf_warning
)
7800 warn_for_address_or_pointer_of_packed_member (type
, val
);
7805 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7806 which just decay_conversion or no conversions at all should be done.
7807 This is true for some builtins which don't act like normal functions.
7808 Return 2 if no conversions at all should be done, 1 if just
7809 decay_conversion. Return 3 for special treatment of the 3rd argument
7810 for __builtin_*_overflow_p. */
7813 magic_varargs_p (tree fn
)
7815 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7816 switch (DECL_FUNCTION_CODE (fn
))
7818 case BUILT_IN_CLASSIFY_TYPE
:
7819 case BUILT_IN_CONSTANT_P
:
7820 case BUILT_IN_NEXT_ARG
:
7821 case BUILT_IN_VA_START
:
7824 case BUILT_IN_ADD_OVERFLOW_P
:
7825 case BUILT_IN_SUB_OVERFLOW_P
:
7826 case BUILT_IN_MUL_OVERFLOW_P
:
7830 return lookup_attribute ("type generic",
7831 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7837 /* Returns the decl of the dispatcher function if FN is a function version. */
7840 get_function_version_dispatcher (tree fn
)
7842 tree dispatcher_decl
= NULL
;
7844 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7845 && DECL_FUNCTION_VERSIONED (fn
));
7847 gcc_assert (targetm
.get_function_versions_dispatcher
);
7848 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7850 if (dispatcher_decl
== NULL
)
7852 error_at (input_location
, "use of multiversioned function "
7853 "without a default");
7857 retrofit_lang_decl (dispatcher_decl
);
7858 gcc_assert (dispatcher_decl
!= NULL
);
7859 return dispatcher_decl
;
7862 /* fn is a function version dispatcher that is marked used. Mark all the
7863 semantically identical function versions it will dispatch as used. */
7866 mark_versions_used (tree fn
)
7868 struct cgraph_node
*node
;
7869 struct cgraph_function_version_info
*node_v
;
7870 struct cgraph_function_version_info
*it_v
;
7872 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7874 node
= cgraph_node::get (fn
);
7878 gcc_assert (node
->dispatcher_function
);
7880 node_v
= node
->function_version ();
7884 /* All semantically identical versions are chained. Traverse and mark each
7885 one of them as used. */
7886 it_v
= node_v
->next
;
7887 while (it_v
!= NULL
)
7889 mark_used (it_v
->this_node
->decl
);
7894 /* Build a call to "the copy constructor" for the type of A, even if it
7895 wouldn't be selected by normal overload resolution. Used for
7899 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7901 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7902 tree binfo
= TYPE_BINFO (ctype
);
7903 tree copy
= get_copy_ctor (ctype
, complain
);
7904 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7905 tree ob
= build_dummy_object (ctype
);
7906 releasing_vec
args (make_tree_vector_single (a
));
7907 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7908 LOOKUP_NORMAL
, NULL
, complain
);
7912 /* Return true iff T refers to a base field. */
7915 is_base_field_ref (tree t
)
7918 if (TREE_CODE (t
) == ADDR_EXPR
)
7919 t
= TREE_OPERAND (t
, 0);
7920 if (TREE_CODE (t
) == COMPONENT_REF
)
7921 t
= TREE_OPERAND (t
, 1);
7922 if (TREE_CODE (t
) == FIELD_DECL
)
7923 return DECL_FIELD_IS_BASE (t
);
7927 /* We can't elide a copy from a function returning by value to a base
7928 subobject, as the callee might clobber tail padding. Return true iff this
7929 could be that case. */
7932 unsafe_copy_elision_p (tree target
, tree exp
)
7934 /* Copy elision only happens with a TARGET_EXPR. */
7935 if (TREE_CODE (exp
) != TARGET_EXPR
)
7937 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7938 /* It's safe to elide the copy for a class with no tail padding. */
7939 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7941 /* It's safe to elide the copy if we aren't initializing a base object. */
7942 if (!is_base_field_ref (target
))
7944 tree init
= TARGET_EXPR_INITIAL (exp
);
7945 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7946 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7947 init
= TREE_OPERAND (init
, 1);
7948 if (TREE_CODE (init
) == COND_EXPR
)
7950 /* We'll end up copying from each of the arms of the COND_EXPR directly
7951 into the target, so look at them. */
7952 if (tree op
= TREE_OPERAND (init
, 1))
7953 if (unsafe_copy_elision_p (target
, op
))
7955 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7957 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7958 && !AGGR_INIT_VIA_CTOR_P (init
));
7961 /* True iff C is a conversion that binds a reference to a prvalue. */
7964 conv_binds_ref_to_prvalue (conversion
*c
)
7966 if (c
->kind
!= ck_ref_bind
)
7968 if (c
->need_temporary_p
)
7971 c
= next_conversion (c
);
7973 if (c
->kind
== ck_rvalue
)
7975 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7977 if (c
->kind
== ck_identity
&& c
->u
.expr
7978 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7984 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7985 class type or a pointer to class type. */
7988 build_trivial_dtor_call (tree instance
)
7990 gcc_assert (!is_dummy_object (instance
));
7992 if (!flag_lifetime_dse
)
7995 return fold_convert (void_type_node
, instance
);
7998 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
8000 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
8002 instance
= cp_build_fold_indirect_ref (instance
);
8005 /* A trivial destructor should still clobber the object. */
8006 tree clobber
= build_clobber (TREE_TYPE (instance
));
8007 return build2 (MODIFY_EXPR
, void_type_node
,
8011 /* Subroutine of the various build_*_call functions. Overload resolution
8012 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
8013 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
8014 bitmask of various LOOKUP_* flags which apply to the call itself. */
8017 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
8020 const vec
<tree
, va_gc
> *args
= cand
->args
;
8021 tree first_arg
= cand
->first_arg
;
8022 conversion
**convs
= cand
->convs
;
8024 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
8029 unsigned int arg_index
= 0;
8033 bool already_used
= false;
8035 /* In a template, there is no need to perform all of the work that
8036 is normally done. We are only interested in the type of the call
8037 expression, i.e., the return type of the function. Any semantic
8038 errors will be deferred until the template is instantiated. */
8039 if (processing_template_decl
)
8043 const tree
*argarray
;
8046 if (undeduced_auto_decl (fn
))
8047 mark_used (fn
, complain
);
8049 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
8053 return_type
= TREE_TYPE (TREE_TYPE (fn
));
8054 nargs
= vec_safe_length (args
);
8055 if (first_arg
== NULL_TREE
)
8056 argarray
= args
->address ();
8064 alcarray
= XALLOCAVEC (tree
, nargs
);
8065 alcarray
[0] = build_this (first_arg
);
8066 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
8067 alcarray
[ix
+ 1] = arg
;
8068 argarray
= alcarray
;
8071 addr
= build_addr_func (fn
, complain
);
8072 if (addr
== error_mark_node
)
8073 return error_mark_node
;
8074 expr
= build_call_array_loc (input_location
, return_type
,
8075 addr
, nargs
, argarray
);
8076 if (TREE_THIS_VOLATILE (fn
) && cfun
)
8077 current_function_returns_abnormally
= 1;
8078 return convert_from_reference (expr
);
8081 /* Give any warnings we noticed during overload resolution. */
8082 if (cand
->warnings
&& (complain
& tf_warning
))
8084 struct candidate_warning
*w
;
8085 for (w
= cand
->warnings
; w
; w
= w
->next
)
8086 joust (cand
, w
->loser
, 1, complain
);
8089 /* Core issue 2327: P0135 doesn't say how to handle the case where the
8090 argument to the copy constructor ends up being a prvalue after
8091 conversion. Let's do the normal processing, but pretend we aren't
8092 actually using the copy constructor. */
8093 bool force_elide
= false;
8094 if (cxx_dialect
>= cxx17
8095 && cand
->num_convs
== 1
8096 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
8097 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8098 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8099 && conv_binds_ref_to_prvalue (convs
[0]))
8102 goto not_really_used
;
8105 /* OK, we're actually calling this inherited constructor; set its deletedness
8106 appropriately. We can get away with doing this here because calling is
8107 the only way to refer to a constructor. */
8108 if (DECL_INHERITED_CTOR (fn
))
8109 deduce_inheriting_ctor (fn
);
8111 /* Make =delete work with SFINAE. */
8112 if (DECL_DELETED_FN (fn
))
8114 if (complain
& tf_error
)
8116 return error_mark_node
;
8119 if (DECL_FUNCTION_MEMBER_P (fn
))
8122 /* If FN is a template function, two cases must be considered.
8127 template <class T> void f();
8129 template <class T> struct B {
8133 struct C : A, B<int> {
8135 using B<int>::g; // #2
8138 In case #1 where `A::f' is a member template, DECL_ACCESS is
8139 recorded in the primary template but not in its specialization.
8140 We check access of FN using its primary template.
8142 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
8143 because it is a member of class template B, DECL_ACCESS is
8144 recorded in the specialization `B<int>::g'. We cannot use its
8145 primary template because `B<T>::g' and `B<int>::g' may have
8146 different access. */
8147 if (DECL_TEMPLATE_INFO (fn
)
8148 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
8149 access_fn
= DECL_TI_TEMPLATE (fn
);
8152 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
8154 return error_mark_node
;
8157 /* If we're checking for implicit delete, don't bother with argument
8159 if (flags
& LOOKUP_SPECULATIVE
)
8161 if (cand
->viable
== 1)
8163 else if (!(complain
& tf_error
))
8164 /* Reject bad conversions now. */
8165 return error_mark_node
;
8166 /* else continue to get conversion error. */
8171 /* N3276 magic doesn't apply to nested calls. */
8172 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8173 complain
&= ~tf_decltype
;
8174 /* No-Cleanup doesn't apply to nested calls either. */
8175 tsubst_flags_t no_cleanup_complain
= complain
;
8176 complain
&= ~tf_no_cleanup
;
8178 /* Find maximum size of vector to hold converted arguments. */
8179 parmlen
= list_length (parm
);
8180 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8181 if (parmlen
> nargs
)
8183 argarray
= XALLOCAVEC (tree
, nargs
);
8185 /* The implicit parameters to a constructor are not considered by overload
8186 resolution, and must be of the proper type. */
8187 if (DECL_CONSTRUCTOR_P (fn
))
8190 if (first_arg
!= NULL_TREE
)
8192 object_arg
= first_arg
;
8193 first_arg
= NULL_TREE
;
8197 object_arg
= (*args
)[arg_index
];
8200 argarray
[j
++] = build_this (object_arg
);
8201 parm
= TREE_CHAIN (parm
);
8202 /* We should never try to call the abstract constructor. */
8203 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8205 if (DECL_HAS_VTT_PARM_P (fn
))
8207 argarray
[j
++] = (*args
)[arg_index
];
8209 parm
= TREE_CHAIN (parm
);
8212 if (flags
& LOOKUP_PREFER_RVALUE
)
8214 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8215 the first parameter of the selected constructor is not an rvalue
8216 reference to the object's type (possibly cv-qualified)...." */
8217 gcc_assert (!(complain
& tf_error
));
8218 tree ptype
= convs
[0]->type
;
8219 if (!TYPE_REF_P (ptype
)
8220 || !TYPE_REF_IS_RVALUE (ptype
)
8221 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8222 return error_mark_node
;
8225 /* Bypass access control for 'this' parameter. */
8226 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8228 tree parmtype
= TREE_VALUE (parm
);
8229 tree arg
= build_this (first_arg
!= NULL_TREE
8231 : (*args
)[arg_index
]);
8232 tree argtype
= TREE_TYPE (arg
);
8236 if (arg
== error_mark_node
)
8237 return error_mark_node
;
8239 if (convs
[i
]->bad_p
)
8241 if (complain
& tf_error
)
8243 auto_diagnostic_group d
;
8244 if (permerror (input_location
, "passing %qT as %<this%> "
8245 "argument discards qualifiers",
8246 TREE_TYPE (argtype
)))
8247 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8250 return error_mark_node
;
8253 /* Optimize away vtable lookup if we know that this
8254 function can't be overridden. We need to check if
8255 the context and the type where we found fn are the same,
8256 actually FN might be defined in a different class
8257 type because of a using-declaration. In this case, we
8258 do not want to perform a non-virtual call. Note that
8259 resolves_to_fixed_type_p checks CLASSTYPE_FINAL too. */
8260 if (DECL_FINAL_P (fn
)
8261 || (resolves_to_fixed_type_p (arg
, 0)
8262 && same_type_ignoring_top_level_qualifiers_p
8263 (DECL_CONTEXT (fn
), BINFO_TYPE (cand
->conversion_path
))))
8264 flags
|= LOOKUP_NONVIRTUAL
;
8266 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8267 X is called for an object that is not of type X, or of a type
8268 derived from X, the behavior is undefined.
8270 So we can assume that anything passed as 'this' is non-null, and
8271 optimize accordingly. */
8272 gcc_assert (TYPE_PTR_P (parmtype
));
8273 /* Convert to the base in which the function was declared. */
8274 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8275 converted_arg
= build_base_path (PLUS_EXPR
,
8277 cand
->conversion_path
,
8279 /* Check that the base class is accessible. */
8280 if (!accessible_base_p (TREE_TYPE (argtype
),
8281 BINFO_TYPE (cand
->conversion_path
), true))
8283 if (complain
& tf_error
)
8284 error ("%qT is not an accessible base of %qT",
8285 BINFO_TYPE (cand
->conversion_path
),
8286 TREE_TYPE (argtype
));
8288 return error_mark_node
;
8290 /* If fn was found by a using declaration, the conversion path
8291 will be to the derived class, not the base declaring fn. We
8292 must convert from derived to base. */
8293 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8294 TREE_TYPE (parmtype
), ba_unique
,
8296 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8297 base_binfo
, 1, complain
);
8299 argarray
[j
++] = converted_arg
;
8300 parm
= TREE_CHAIN (parm
);
8301 if (first_arg
!= NULL_TREE
)
8302 first_arg
= NULL_TREE
;
8309 gcc_assert (first_arg
== NULL_TREE
);
8310 for (; arg_index
< vec_safe_length (args
) && parm
;
8311 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8313 tree type
= TREE_VALUE (parm
);
8314 tree arg
= (*args
)[arg_index
];
8315 bool conversion_warning
= true;
8319 /* If the argument is NULL and used to (implicitly) instantiate a
8320 template function (and bind one of the template arguments to
8321 the type of 'long int'), we don't want to warn about passing NULL
8322 to non-pointer argument.
8323 For example, if we have this template function:
8325 template<typename T> void func(T x) {}
8327 we want to warn (when -Wconversion is enabled) in this case:
8333 but not in this case:
8339 if (null_node_p (arg
)
8340 && DECL_TEMPLATE_INFO (fn
)
8341 && cand
->template_decl
8342 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8343 conversion_warning
= false;
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_input_loc (arg
);
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 "
8584 "not 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 If FN is the result of resolving an overloaded target built-in,
9109 ORIG_FNDECL is the original function decl, otherwise it is null.
9110 This function performs no overload resolution, conversion, or other
9111 high-level operations. */
9114 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
9115 tsubst_flags_t complain
, tree orig_fndecl
)
9119 /* Remember roughly where this call is. */
9120 location_t loc
= cp_expr_loc_or_input_loc (fn
);
9121 fn
= build_call_a (fn
, nargs
, argarray
);
9122 SET_EXPR_LOCATION (fn
, loc
);
9124 fndecl
= get_callee_fndecl (fn
);
9126 orig_fndecl
= fndecl
;
9128 /* Check that arguments to builtin functions match the expectations. */
9130 && !processing_template_decl
9131 && fndecl_built_in_p (fndecl
))
9135 /* We need to take care that values to BUILT_IN_NORMAL
9137 for (i
= 0; i
< nargs
; i
++)
9138 argarray
[i
] = maybe_constant_value (argarray
[i
]);
9140 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
9141 orig_fndecl
, nargs
, argarray
))
9142 return error_mark_node
;
9145 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9148 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9149 function call is either the operand of a decltype-specifier or the
9150 right operand of a comma operator that is the operand of a
9151 decltype-specifier, a temporary object is not introduced for the
9152 prvalue. The type of the prvalue may be incomplete. */
9153 if (!(complain
& tf_decltype
))
9155 fn
= require_complete_type_sfinae (fn
, complain
);
9156 if (fn
== error_mark_node
)
9157 return error_mark_node
;
9159 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9161 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9162 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9165 return convert_from_reference (fn
);
9168 /* Returns the value to use for the in-charge parameter when making a
9169 call to a function with the indicated NAME.
9171 FIXME:Can't we find a neater way to do this mapping? */
9174 in_charge_arg_for_name (tree name
)
9176 if (IDENTIFIER_CTOR_P (name
))
9178 if (name
== complete_ctor_identifier
)
9179 return integer_one_node
;
9180 gcc_checking_assert (name
== base_ctor_identifier
);
9184 if (name
== complete_dtor_identifier
)
9185 return integer_two_node
;
9186 else if (name
== deleting_dtor_identifier
)
9187 return integer_three_node
;
9188 gcc_checking_assert (name
== base_dtor_identifier
);
9191 return integer_zero_node
;
9194 /* We've built up a constructor call RET. Complain if it delegates to the
9195 constructor we're currently compiling. */
9198 check_self_delegation (tree ret
)
9200 if (TREE_CODE (ret
) == TARGET_EXPR
)
9201 ret
= TARGET_EXPR_INITIAL (ret
);
9202 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9203 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9204 error ("constructor delegates to itself");
9207 /* Build a call to a constructor, destructor, or an assignment
9208 operator for INSTANCE, an expression with class type. NAME
9209 indicates the special member function to call; *ARGS are the
9210 arguments. ARGS may be NULL. This may change ARGS. BINFO
9211 indicates the base of INSTANCE that is to be passed as the `this'
9212 parameter to the member function called.
9214 FLAGS are the LOOKUP_* flags to use when processing the call.
9216 If NAME indicates a complete object constructor, INSTANCE may be
9217 NULL_TREE. In this case, the caller will call build_cplus_new to
9218 store the newly constructed object into a VAR_DECL. */
9221 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9222 tree binfo
, int flags
, tsubst_flags_t complain
)
9225 /* The type of the subobject to be constructed or destroyed. */
9227 vec
<tree
, va_gc
> *allocated
= NULL
;
9230 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9232 if (error_operand_p (instance
))
9233 return error_mark_node
;
9235 if (IDENTIFIER_DTOR_P (name
))
9237 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9238 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9239 /* Shortcut to avoid lazy destructor declaration. */
9240 return build_trivial_dtor_call (instance
);
9245 /* Resolve the name. */
9246 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9247 return error_mark_node
;
9249 binfo
= TYPE_BINFO (binfo
);
9252 gcc_assert (binfo
!= NULL_TREE
);
9254 class_type
= BINFO_TYPE (binfo
);
9256 /* Handle the special case where INSTANCE is NULL_TREE. */
9257 if (name
== complete_ctor_identifier
&& !instance
)
9258 instance
= build_dummy_object (class_type
);
9261 /* Convert to the base class, if necessary. */
9262 if (!same_type_ignoring_top_level_qualifiers_p
9263 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9265 if (IDENTIFIER_CDTOR_P (name
))
9266 /* For constructors and destructors, either the base is
9267 non-virtual, or it is virtual but we are doing the
9268 conversion from a constructor or destructor for the
9269 complete object. In either case, we can convert
9271 instance
= convert_to_base_statically (instance
, binfo
);
9274 /* However, for assignment operators, we must convert
9275 dynamically if the base is virtual. */
9276 gcc_checking_assert (name
== assign_op_identifier
);
9277 instance
= build_base_path (PLUS_EXPR
, instance
,
9278 binfo
, /*nonnull=*/1, complain
);
9283 gcc_assert (instance
!= NULL_TREE
);
9285 /* In C++17, "If the initializer expression is a prvalue and the
9286 cv-unqualified version of the source type is the same class as the class
9287 of the destination, the initializer expression is used to initialize the
9288 destination object." Handle that here to avoid doing overload
9290 if (cxx_dialect
>= cxx17
9291 && args
&& vec_safe_length (*args
) == 1
9292 && name
== complete_ctor_identifier
)
9294 tree arg
= (**args
)[0];
9296 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9297 && !TYPE_HAS_LIST_CTOR (class_type
)
9298 && CONSTRUCTOR_NELTS (arg
) == 1)
9299 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9301 if ((TREE_CODE (arg
) == TARGET_EXPR
9302 || TREE_CODE (arg
) == CONSTRUCTOR
)
9303 && (same_type_ignoring_top_level_qualifiers_p
9304 (class_type
, TREE_TYPE (arg
))))
9306 if (is_dummy_object (instance
))
9308 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9309 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9311 if ((complain
& tf_error
)
9312 && (flags
& LOOKUP_DELEGATING_CONS
))
9313 check_self_delegation (arg
);
9314 /* Avoid change of behavior on Wunused-var-2.C. */
9315 instance
= mark_lvalue_use (instance
);
9316 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9320 fns
= lookup_fnfields (binfo
, name
, 1);
9322 /* When making a call to a constructor or destructor for a subobject
9323 that uses virtual base classes, pass down a pointer to a VTT for
9325 if ((name
== base_ctor_identifier
9326 || name
== base_dtor_identifier
)
9327 && CLASSTYPE_VBASECLASSES (class_type
))
9332 /* If the current function is a complete object constructor
9333 or destructor, then we fetch the VTT directly.
9334 Otherwise, we look it up using the VTT we were given. */
9335 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9336 vtt
= decay_conversion (vtt
, complain
);
9337 if (vtt
== error_mark_node
)
9338 return error_mark_node
;
9339 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9340 if (BINFO_SUBVTT_INDEX (binfo
))
9341 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9347 allocated
= make_tree_vector ();
9351 vec_safe_insert (*args
, 0, sub_vtt
);
9354 ret
= build_new_method_call (instance
, fns
, args
,
9355 TYPE_BINFO (BINFO_TYPE (binfo
)),
9359 if (allocated
!= NULL
)
9360 release_tree_vector (allocated
);
9362 if ((complain
& tf_error
)
9363 && (flags
& LOOKUP_DELEGATING_CONS
)
9364 && name
== complete_ctor_identifier
)
9365 check_self_delegation (ret
);
9370 /* Return the NAME, as a C string. The NAME indicates a function that
9371 is a member of TYPE. *FREE_P is set to true if the caller must
9372 free the memory returned.
9374 Rather than go through all of this, we should simply set the names
9375 of constructors and destructors appropriately, and dispense with
9376 ctor_identifier, dtor_identifier, etc. */
9379 name_as_c_string (tree name
, tree type
, bool *free_p
)
9381 const char *pretty_name
;
9383 /* Assume that we will not allocate memory. */
9385 /* Constructors and destructors are special. */
9386 if (IDENTIFIER_CDTOR_P (name
))
9389 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9390 /* For a destructor, add the '~'. */
9391 if (IDENTIFIER_DTOR_P (name
))
9393 pretty_name
= concat ("~", pretty_name
, NULL
);
9394 /* Remember that we need to free the memory allocated. */
9398 else if (IDENTIFIER_CONV_OP_P (name
))
9400 pretty_name
= concat ("operator ",
9401 type_as_string_translate (TREE_TYPE (name
),
9402 TFF_PLAIN_IDENTIFIER
),
9404 /* Remember that we need to free the memory allocated. */
9408 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9410 return CONST_CAST (char *, pretty_name
);
9413 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9416 static z_candidate
*
9417 single_z_candidate (z_candidate
*candidates
)
9419 if (candidates
== NULL
)
9422 if (candidates
->next
)
9428 /* If CANDIDATE is invalid due to a bad argument type, return the
9429 pertinent conversion_info.
9431 Otherwise, return NULL. */
9433 static const conversion_info
*
9434 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9436 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9437 rejection_reason
*r
= candidate
->reason
;
9447 case rr_arg_conversion
:
9448 return &r
->u
.conversion
;
9450 case rr_bad_arg_conversion
:
9451 return &r
->u
.bad_conversion
;
9455 /* Issue an error and note complaining about a bad argument type at a
9456 callsite with a single candidate FNDECL.
9458 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9459 case input_location is used).
9460 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9461 the formal parameter. */
9464 complain_about_bad_argument (location_t arg_loc
,
9465 tree from_type
, tree to_type
,
9466 tree fndecl
, int parmnum
)
9468 auto_diagnostic_group d
;
9469 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9470 range_label
*label
= &rhs_label
;
9471 if (arg_loc
== UNKNOWN_LOCATION
)
9473 arg_loc
= input_location
;
9476 gcc_rich_location
richloc (arg_loc
, label
);
9478 "cannot convert %qH to %qI",
9479 from_type
, to_type
);
9480 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9484 /* Subroutine of build_new_method_call_1, for where there are no viable
9485 candidates for the call. */
9488 complain_about_no_candidates_for_method_call (tree instance
,
9489 z_candidate
*candidates
,
9490 tree explicit_targs
,
9492 tree optype
, tree name
,
9493 bool skip_first_for_error
,
9494 vec
<tree
, va_gc
> *user_args
)
9496 auto_diagnostic_group d
;
9497 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9498 cxx_incomplete_type_error (instance
, basetype
);
9500 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9501 basetype
, optype
, build_tree_list_vec (user_args
),
9502 TREE_TYPE (instance
));
9505 /* Special-case for when there's a single candidate that's failing
9506 due to a bad argument type. */
9507 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9508 if (const conversion_info
*conv
9509 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9511 complain_about_bad_argument (conv
->loc
,
9512 conv
->from
, conv
->to_type
,
9513 candidate
->fn
, conv
->n_arg
);
9517 tree arglist
= build_tree_list_vec (user_args
);
9518 tree errname
= name
;
9519 bool twiddle
= false;
9520 if (IDENTIFIER_CDTOR_P (errname
))
9522 twiddle
= IDENTIFIER_DTOR_P (errname
);
9523 errname
= constructor_name (basetype
);
9526 errname
= lookup_template_function (errname
, explicit_targs
);
9527 if (skip_first_for_error
)
9528 arglist
= TREE_CHAIN (arglist
);
9529 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9530 basetype
, &"~"[!twiddle
], errname
, arglist
,
9531 TREE_TYPE (instance
));
9533 print_z_candidates (location_of (name
), candidates
);
9536 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9537 be set, upon return, to the function called. ARGS may be NULL.
9538 This may change ARGS. */
9541 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9542 tree conversion_path
, int flags
,
9543 tree
*fn_p
, tsubst_flags_t complain
)
9545 struct z_candidate
*candidates
= 0, *cand
;
9546 tree explicit_targs
= NULL_TREE
;
9547 tree basetype
= NULL_TREE
;
9550 tree first_mem_arg
= NULL_TREE
;
9552 bool skip_first_for_error
;
9553 vec
<tree
, va_gc
> *user_args
;
9556 int template_only
= 0;
9560 vec
<tree
, va_gc
> *orig_args
= NULL
;
9563 gcc_assert (instance
!= NULL_TREE
);
9565 /* We don't know what function we're going to call, yet. */
9569 if (error_operand_p (instance
)
9570 || !fns
|| error_operand_p (fns
))
9571 return error_mark_node
;
9573 if (!BASELINK_P (fns
))
9575 if (complain
& tf_error
)
9576 error ("call to non-function %qD", fns
);
9577 return error_mark_node
;
9580 orig_instance
= instance
;
9583 /* Dismantle the baselink to collect all the information we need. */
9584 if (!conversion_path
)
9585 conversion_path
= BASELINK_BINFO (fns
);
9586 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9587 optype
= BASELINK_OPTYPE (fns
);
9588 fns
= BASELINK_FUNCTIONS (fns
);
9589 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9591 explicit_targs
= TREE_OPERAND (fns
, 1);
9592 fns
= TREE_OPERAND (fns
, 0);
9595 gcc_assert (OVL_P (fns
));
9596 fn
= OVL_FIRST (fns
);
9597 name
= DECL_NAME (fn
);
9599 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9600 gcc_assert (CLASS_TYPE_P (basetype
));
9602 user_args
= args
== NULL
? NULL
: *args
;
9603 /* Under DR 147 A::A() is an invalid constructor call,
9604 not a functional cast. */
9605 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9607 if (! (complain
& tf_error
))
9608 return error_mark_node
;
9610 basetype
= DECL_CONTEXT (fn
);
9611 name
= constructor_name (basetype
);
9612 auto_diagnostic_group d
;
9613 if (permerror (input_location
,
9614 "cannot call constructor %<%T::%D%> directly",
9616 inform (input_location
, "for a function-style cast, remove the "
9617 "redundant %<::%D%>", name
);
9618 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9623 if (processing_template_decl
)
9625 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9626 instance
= build_non_dependent_expr (instance
);
9628 make_args_non_dependent (*args
);
9631 /* Process the argument list. */
9632 if (args
!= NULL
&& *args
!= NULL
)
9634 *args
= resolve_args (*args
, complain
);
9636 return error_mark_node
;
9640 /* Consider the object argument to be used even if we end up selecting a
9641 static member function. */
9642 instance
= mark_type_use (instance
);
9644 /* Figure out whether to skip the first argument for the error
9645 message we will display to users if an error occurs. We don't
9646 want to display any compiler-generated arguments. The "this"
9647 pointer hasn't been added yet. However, we must remove the VTT
9648 pointer if this is a call to a base-class constructor or
9650 skip_first_for_error
= false;
9651 if (IDENTIFIER_CDTOR_P (name
))
9653 /* Callers should explicitly indicate whether they want to ctor
9654 the complete object or just the part without virtual bases. */
9655 gcc_assert (name
!= ctor_identifier
);
9657 /* Remove the VTT pointer, if present. */
9658 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9659 && CLASSTYPE_VBASECLASSES (basetype
))
9660 skip_first_for_error
= true;
9662 /* It's OK to call destructors and constructors on cv-qualified
9663 objects. Therefore, convert the INSTANCE to the unqualified
9664 type, if necessary. */
9665 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9667 instance
= build_this (instance
);
9668 instance
= build_nop (build_pointer_type (basetype
), instance
);
9669 instance
= build_fold_indirect_ref (instance
);
9673 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9675 /* For the overload resolution we need to find the actual `this`
9676 that would be captured if the call turns out to be to a
9677 non-static member function. Do not actually capture it at this
9679 if (DECL_CONSTRUCTOR_P (fn
))
9680 /* Constructors don't use the enclosing 'this'. */
9681 first_mem_arg
= instance
;
9683 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9685 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9686 p
= conversion_obstack_alloc (0);
9688 /* The number of arguments artificial parms in ARGS; we subtract one because
9689 there's no 'this' in ARGS. */
9690 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9692 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9693 initializer, not T({ }). */
9694 if (DECL_CONSTRUCTOR_P (fn
)
9695 && vec_safe_length (user_args
) > skip
9696 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9698 tree init_list
= (*user_args
)[skip
];
9699 tree init
= NULL_TREE
;
9701 gcc_assert (user_args
->length () == skip
+ 1
9702 && !(flags
& LOOKUP_ONLYCONVERTING
));
9704 /* If the initializer list has no elements and T is a class type with
9705 a default constructor, the object is value-initialized. Handle
9706 this here so we don't need to handle it wherever we use
9707 build_special_member_call. */
9708 if (CONSTRUCTOR_NELTS (init_list
) == 0
9709 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9710 /* For a user-provided default constructor, use the normal
9711 mechanisms so that protected access works. */
9712 && type_has_non_user_provided_default_constructor (basetype
)
9713 && !processing_template_decl
)
9714 init
= build_value_init (basetype
, complain
);
9716 /* If BASETYPE is an aggregate, we need to do aggregate
9718 else if (CP_AGGREGATE_TYPE_P (basetype
))
9720 init
= reshape_init (basetype
, init_list
, complain
);
9721 init
= digest_init (basetype
, init
, complain
);
9726 if (is_dummy_object (instance
))
9727 return get_target_expr_sfinae (init
, complain
);
9728 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9729 TREE_SIDE_EFFECTS (init
) = true;
9733 /* Otherwise go ahead with overload resolution. */
9734 add_list_candidates (fns
, first_mem_arg
, user_args
,
9735 basetype
, explicit_targs
, template_only
,
9736 conversion_path
, access_binfo
, flags
,
9737 &candidates
, complain
);
9740 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9741 explicit_targs
, template_only
, conversion_path
,
9742 access_binfo
, flags
, &candidates
, complain
);
9744 any_viable_p
= false;
9745 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9749 if (complain
& tf_error
)
9750 complain_about_no_candidates_for_method_call (instance
, candidates
,
9751 explicit_targs
, basetype
,
9753 skip_first_for_error
,
9755 call
= error_mark_node
;
9759 cand
= tourney (candidates
, complain
);
9766 if (complain
& tf_error
)
9768 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9769 arglist
= build_tree_list_vec (user_args
);
9770 if (skip_first_for_error
)
9771 arglist
= TREE_CHAIN (arglist
);
9772 auto_diagnostic_group d
;
9773 if (!any_strictly_viable (candidates
))
9774 error ("no matching function for call to %<%s(%A)%>",
9775 pretty_name
, arglist
);
9777 error ("call of overloaded %<%s(%A)%> is ambiguous",
9778 pretty_name
, arglist
);
9779 print_z_candidates (location_of (name
), candidates
);
9783 call
= error_mark_node
;
9790 if (!(flags
& LOOKUP_NONVIRTUAL
)
9791 && DECL_PURE_VIRTUAL_P (fn
)
9792 && instance
== current_class_ref
9793 && (complain
& tf_warning
))
9795 /* This is not an error, it is runtime undefined
9797 if (!current_function_decl
)
9798 warning (0, "pure virtual %q#D called from "
9799 "non-static data member initializer", fn
);
9800 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9801 || DECL_DESTRUCTOR_P (current_function_decl
))
9802 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9803 ? G_("pure virtual %q#D called from constructor")
9804 : G_("pure virtual %q#D called from destructor")),
9808 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9809 && !DECL_CONSTRUCTOR_P (fn
)
9810 && is_dummy_object (instance
))
9812 instance
= maybe_resolve_dummy (instance
, true);
9813 if (instance
== error_mark_node
)
9814 call
= error_mark_node
;
9815 else if (!is_dummy_object (instance
))
9817 /* We captured 'this' in the current lambda now that
9818 we know we really need it. */
9819 cand
->first_arg
= instance
;
9821 else if (any_dependent_bases_p ())
9822 /* We can't tell until instantiation time whether we can use
9823 *this as the implicit object argument. */;
9826 if (complain
& tf_error
)
9827 error ("cannot call member function %qD without object",
9829 call
= error_mark_node
;
9833 if (call
!= error_mark_node
)
9836 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9837 /* Now we know what function is being called. */
9840 /* Build the actual CALL_EXPR. */
9841 call
= build_over_call (cand
, flags
, complain
);
9842 /* In an expression of the form `a->f()' where `f' turns
9843 out to be a static member function, `a' is
9844 none-the-less evaluated. */
9845 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9846 && !is_dummy_object (instance
)
9847 && TREE_SIDE_EFFECTS (instance
))
9849 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9852 if (TREE_THIS_VOLATILE (a
))
9854 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9856 else if (call
!= error_mark_node
9857 && DECL_DESTRUCTOR_P (cand
->fn
)
9858 && !VOID_TYPE_P (TREE_TYPE (call
)))
9859 /* An explicit call of the form "x->~X()" has type
9860 "void". However, on platforms where destructors
9861 return "this" (i.e., those where
9862 targetm.cxx.cdtor_returns_this is true), such calls
9863 will appear to have a return value of pointer type
9864 to the low-level call machinery. We do not want to
9865 change the low-level machinery, since we want to be
9866 able to optimize "delete f()" on such platforms as
9867 "operator delete(~X(f()))" (rather than generating
9868 "t = f(), ~X(t), operator delete (t)"). */
9869 call
= build_nop (void_type_node
, call
);
9874 if (processing_template_decl
&& call
!= error_mark_node
)
9876 bool cast_to_void
= false;
9878 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9879 call
= TREE_OPERAND (call
, 1);
9880 else if (TREE_CODE (call
) == NOP_EXPR
)
9882 cast_to_void
= true;
9883 call
= TREE_OPERAND (call
, 0);
9885 if (INDIRECT_REF_P (call
))
9886 call
= TREE_OPERAND (call
, 0);
9887 call
= (build_min_non_dep_call_vec
9889 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9890 orig_instance
, orig_fns
, NULL_TREE
),
9892 SET_EXPR_LOCATION (call
, input_location
);
9893 call
= convert_from_reference (call
);
9895 call
= build_nop (void_type_node
, call
);
9898 /* Free all the conversions we allocated. */
9899 obstack_free (&conversion_obstack
, p
);
9901 if (orig_args
!= NULL
)
9902 release_tree_vector (orig_args
);
9907 /* Wrapper for above. */
9910 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9911 tree conversion_path
, int flags
,
9912 tree
*fn_p
, tsubst_flags_t complain
)
9915 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9916 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9918 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9922 /* Returns true iff standard conversion sequence ICS1 is a proper
9923 subsequence of ICS2. */
9926 is_subseq (conversion
*ics1
, conversion
*ics2
)
9928 /* We can assume that a conversion of the same code
9929 between the same types indicates a subsequence since we only get
9930 here if the types we are converting from are the same. */
9932 while (ics1
->kind
== ck_rvalue
9933 || ics1
->kind
== ck_lvalue
)
9934 ics1
= next_conversion (ics1
);
9938 while (ics2
->kind
== ck_rvalue
9939 || ics2
->kind
== ck_lvalue
)
9940 ics2
= next_conversion (ics2
);
9942 if (ics2
->kind
== ck_user
9943 || ics2
->kind
== ck_ambig
9944 || ics2
->kind
== ck_aggr
9945 || ics2
->kind
== ck_list
9946 || ics2
->kind
== ck_identity
)
9947 /* At this point, ICS1 cannot be a proper subsequence of
9948 ICS2. We can get a USER_CONV when we are comparing the
9949 second standard conversion sequence of two user conversion
9953 ics2
= next_conversion (ics2
);
9955 while (ics2
->kind
== ck_rvalue
9956 || ics2
->kind
== ck_lvalue
)
9957 ics2
= next_conversion (ics2
);
9959 if (ics2
->kind
== ics1
->kind
9960 && same_type_p (ics2
->type
, ics1
->type
)
9961 && (ics1
->kind
== ck_identity
9962 || same_type_p (next_conversion (ics2
)->type
,
9963 next_conversion (ics1
)->type
)))
9968 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9969 be any _TYPE nodes. */
9972 is_properly_derived_from (tree derived
, tree base
)
9974 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
9977 /* We only allow proper derivation here. The DERIVED_FROM_P macro
9978 considers every class derived from itself. */
9979 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
9980 && DERIVED_FROM_P (base
, derived
));
9983 /* We build the ICS for an implicit object parameter as a pointer
9984 conversion sequence. However, such a sequence should be compared
9985 as if it were a reference conversion sequence. If ICS is the
9986 implicit conversion sequence for an implicit object parameter,
9987 modify it accordingly. */
9990 maybe_handle_implicit_object (conversion
**ics
)
9994 /* [over.match.funcs]
9996 For non-static member functions, the type of the
9997 implicit object parameter is "reference to cv X"
9998 where X is the class of which the function is a
9999 member and cv is the cv-qualification on the member
10000 function declaration. */
10001 conversion
*t
= *ics
;
10002 tree reference_type
;
10004 /* The `this' parameter is a pointer to a class type. Make the
10005 implicit conversion talk about a reference to that same class
10007 reference_type
= TREE_TYPE (t
->type
);
10008 reference_type
= build_reference_type (reference_type
);
10010 if (t
->kind
== ck_qual
)
10011 t
= next_conversion (t
);
10012 if (t
->kind
== ck_ptr
)
10013 t
= next_conversion (t
);
10014 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
10015 t
= direct_reference_binding (reference_type
, t
);
10017 t
->rvaluedness_matches_p
= 0;
10022 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
10023 and return the initial reference binding conversion. Otherwise,
10024 leave *ICS unchanged and return NULL. */
10026 static conversion
*
10027 maybe_handle_ref_bind (conversion
**ics
)
10029 if ((*ics
)->kind
== ck_ref_bind
)
10031 conversion
*old_ics
= *ics
;
10032 *ics
= next_conversion (old_ics
);
10033 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
10040 /* Compare two implicit conversion sequences according to the rules set out in
10041 [over.ics.rank]. Return values:
10043 1: ics1 is better than ics2
10044 -1: ics2 is better than ics1
10045 0: ics1 and ics2 are indistinguishable */
10048 compare_ics (conversion
*ics1
, conversion
*ics2
)
10054 tree deref_from_type1
= NULL_TREE
;
10055 tree deref_from_type2
= NULL_TREE
;
10056 tree deref_to_type1
= NULL_TREE
;
10057 tree deref_to_type2
= NULL_TREE
;
10058 conversion_rank rank1
, rank2
;
10060 /* REF_BINDING is nonzero if the result of the conversion sequence
10061 is a reference type. In that case REF_CONV is the reference
10062 binding conversion. */
10063 conversion
*ref_conv1
;
10064 conversion
*ref_conv2
;
10066 /* Compare badness before stripping the reference conversion. */
10067 if (ics1
->bad_p
> ics2
->bad_p
)
10069 else if (ics1
->bad_p
< ics2
->bad_p
)
10072 /* Handle implicit object parameters. */
10073 maybe_handle_implicit_object (&ics1
);
10074 maybe_handle_implicit_object (&ics2
);
10076 /* Handle reference parameters. */
10077 ref_conv1
= maybe_handle_ref_bind (&ics1
);
10078 ref_conv2
= maybe_handle_ref_bind (&ics2
);
10080 /* List-initialization sequence L1 is a better conversion sequence than
10081 list-initialization sequence L2 if L1 converts to
10082 std::initializer_list<X> for some X and L2 does not. */
10083 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
10085 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
10090 When comparing the basic forms of implicit conversion sequences (as
10091 defined in _over.best.ics_)
10093 --a standard conversion sequence (_over.ics.scs_) is a better
10094 conversion sequence than a user-defined conversion sequence
10095 or an ellipsis conversion sequence, and
10097 --a user-defined conversion sequence (_over.ics.user_) is a
10098 better conversion sequence than an ellipsis conversion sequence
10099 (_over.ics.ellipsis_). */
10100 /* Use BAD_CONVERSION_RANK because we already checked for a badness
10101 mismatch. If both ICS are bad, we try to make a decision based on
10102 what would have happened if they'd been good. This is not an
10103 extension, we'll still give an error when we build up the call; this
10104 just helps us give a more helpful error message. */
10105 rank1
= BAD_CONVERSION_RANK (ics1
);
10106 rank2
= BAD_CONVERSION_RANK (ics2
);
10110 else if (rank1
< rank2
)
10113 if (ics1
->ellipsis_p
)
10114 /* Both conversions are ellipsis conversions. */
10117 /* User-defined conversion sequence U1 is a better conversion sequence
10118 than another user-defined conversion sequence U2 if they contain the
10119 same user-defined conversion operator or constructor and if the sec-
10120 ond standard conversion sequence of U1 is better than the second
10121 standard conversion sequence of U2. */
10123 /* Handle list-conversion with the same code even though it isn't always
10124 ranked as a user-defined conversion and it doesn't have a second
10125 standard conversion sequence; it will still have the desired effect.
10126 Specifically, we need to do the reference binding comparison at the
10127 end of this function. */
10129 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
10130 || ics1
->kind
== ck_aggr
|| ics2
->kind
== ck_aggr
)
10135 for (t1
= ics1
; t1
&& t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
10136 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
10137 || t1
->kind
== ck_list
)
10139 for (t2
= ics2
; t2
&& t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
10140 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
10141 || t2
->kind
== ck_list
)
10144 if (!t1
|| !t2
|| t1
->kind
!= t2
->kind
)
10146 else if (t1
->kind
== ck_user
)
10148 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10149 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10155 /* For ambiguous or aggregate conversions, use the target type as
10156 a proxy for the conversion function. */
10157 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10161 /* We can just fall through here, after setting up
10162 FROM_TYPE1 and FROM_TYPE2. */
10163 from_type1
= t1
->type
;
10164 from_type2
= t2
->type
;
10171 /* We're dealing with two standard conversion sequences.
10175 Standard conversion sequence S1 is a better conversion
10176 sequence than standard conversion sequence S2 if
10178 --S1 is a proper subsequence of S2 (comparing the conversion
10179 sequences in the canonical form defined by _over.ics.scs_,
10180 excluding any Lvalue Transformation; the identity
10181 conversion sequence is considered to be a subsequence of
10182 any non-identity conversion sequence */
10185 while (t1
->kind
!= ck_identity
)
10186 t1
= next_conversion (t1
);
10187 from_type1
= t1
->type
;
10190 while (t2
->kind
!= ck_identity
)
10191 t2
= next_conversion (t2
);
10192 from_type2
= t2
->type
;
10195 /* One sequence can only be a subsequence of the other if they start with
10196 the same type. They can start with different types when comparing the
10197 second standard conversion sequence in two user-defined conversion
10199 if (same_type_p (from_type1
, from_type2
))
10201 if (is_subseq (ics1
, ics2
))
10203 if (is_subseq (ics2
, ics1
))
10211 --the rank of S1 is better than the rank of S2 (by the rules
10214 Standard conversion sequences are ordered by their ranks: an Exact
10215 Match is a better conversion than a Promotion, which is a better
10216 conversion than a Conversion.
10218 Two conversion sequences with the same rank are indistinguishable
10219 unless one of the following rules applies:
10221 --A conversion that does not a convert a pointer, pointer to member,
10222 or std::nullptr_t to bool is better than one that does.
10224 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10225 so that we do not have to check it explicitly. */
10226 if (ics1
->rank
< ics2
->rank
)
10228 else if (ics2
->rank
< ics1
->rank
)
10231 to_type1
= ics1
->type
;
10232 to_type2
= ics2
->type
;
10234 /* A conversion from scalar arithmetic type to complex is worse than a
10235 conversion between scalar arithmetic types. */
10236 if (same_type_p (from_type1
, from_type2
)
10237 && ARITHMETIC_TYPE_P (from_type1
)
10238 && ARITHMETIC_TYPE_P (to_type1
)
10239 && ARITHMETIC_TYPE_P (to_type2
)
10240 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10241 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10243 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10249 if (TYPE_PTR_P (from_type1
)
10250 && TYPE_PTR_P (from_type2
)
10251 && TYPE_PTR_P (to_type1
)
10252 && TYPE_PTR_P (to_type2
))
10254 deref_from_type1
= TREE_TYPE (from_type1
);
10255 deref_from_type2
= TREE_TYPE (from_type2
);
10256 deref_to_type1
= TREE_TYPE (to_type1
);
10257 deref_to_type2
= TREE_TYPE (to_type2
);
10259 /* The rules for pointers to members A::* are just like the rules
10260 for pointers A*, except opposite: if B is derived from A then
10261 A::* converts to B::*, not vice versa. For that reason, we
10262 switch the from_ and to_ variables here. */
10263 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10264 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10265 || (TYPE_PTRMEMFUNC_P (from_type1
)
10266 && TYPE_PTRMEMFUNC_P (from_type2
)
10267 && TYPE_PTRMEMFUNC_P (to_type1
)
10268 && TYPE_PTRMEMFUNC_P (to_type2
)))
10270 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10271 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10272 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10273 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10276 if (deref_from_type1
!= NULL_TREE
10277 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10278 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10280 /* This was one of the pointer or pointer-like conversions.
10284 --If class B is derived directly or indirectly from class A,
10285 conversion of B* to A* is better than conversion of B* to
10286 void*, and conversion of A* to void* is better than
10287 conversion of B* to void*. */
10288 if (VOID_TYPE_P (deref_to_type1
)
10289 && VOID_TYPE_P (deref_to_type2
))
10291 if (is_properly_derived_from (deref_from_type1
,
10294 else if (is_properly_derived_from (deref_from_type2
,
10298 else if (VOID_TYPE_P (deref_to_type1
)
10299 || VOID_TYPE_P (deref_to_type2
))
10301 if (same_type_p (deref_from_type1
, deref_from_type2
))
10303 if (VOID_TYPE_P (deref_to_type2
))
10305 if (is_properly_derived_from (deref_from_type1
,
10309 /* We know that DEREF_TO_TYPE1 is `void' here. */
10310 else if (is_properly_derived_from (deref_from_type1
,
10315 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10316 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10320 --If class B is derived directly or indirectly from class A
10321 and class C is derived directly or indirectly from B,
10323 --conversion of C* to B* is better than conversion of C* to
10326 --conversion of B* to A* is better than conversion of C* to
10328 if (same_type_p (deref_from_type1
, deref_from_type2
))
10330 if (is_properly_derived_from (deref_to_type1
,
10333 else if (is_properly_derived_from (deref_to_type2
,
10337 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10339 if (is_properly_derived_from (deref_from_type2
,
10342 else if (is_properly_derived_from (deref_from_type1
,
10348 else if (CLASS_TYPE_P (non_reference (from_type1
))
10349 && same_type_p (from_type1
, from_type2
))
10351 tree from
= non_reference (from_type1
);
10355 --binding of an expression of type C to a reference of type
10356 B& is better than binding an expression of type C to a
10357 reference of type A&
10359 --conversion of C to B is better than conversion of C to A, */
10360 if (is_properly_derived_from (from
, to_type1
)
10361 && is_properly_derived_from (from
, to_type2
))
10363 if (is_properly_derived_from (to_type1
, to_type2
))
10365 else if (is_properly_derived_from (to_type2
, to_type1
))
10369 else if (CLASS_TYPE_P (non_reference (to_type1
))
10370 && same_type_p (to_type1
, to_type2
))
10372 tree to
= non_reference (to_type1
);
10376 --binding of an expression of type B to a reference of type
10377 A& is better than binding an expression of type C to a
10378 reference of type A&,
10380 --conversion of B to A is better than conversion of C to A */
10381 if (is_properly_derived_from (from_type1
, to
)
10382 && is_properly_derived_from (from_type2
, to
))
10384 if (is_properly_derived_from (from_type2
, from_type1
))
10386 else if (is_properly_derived_from (from_type1
, from_type2
))
10393 --S1 and S2 differ only in their qualification conversion and yield
10394 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10395 qualification signature of type T1 is a proper subset of the cv-
10396 qualification signature of type T2 */
10397 if (ics1
->kind
== ck_qual
10398 && ics2
->kind
== ck_qual
10399 && same_type_p (from_type1
, from_type2
))
10401 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10408 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10409 to an implicit object parameter of a non-static member function
10410 declared without a ref-qualifier, and either S1 binds an lvalue
10411 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10412 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10413 draft standard, 13.3.3.2)
10415 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10416 types to which the references refer are the same type except for
10417 top-level cv-qualifiers, and the type to which the reference
10418 initialized by S2 refers is more cv-qualified than the type to
10419 which the reference initialized by S1 refers.
10421 DR 1328 [over.match.best]: the context is an initialization by
10422 conversion function for direct reference binding (13.3.1.6) of a
10423 reference to function type, the return type of F1 is the same kind of
10424 reference (i.e. lvalue or rvalue) as the reference being initialized,
10425 and the return type of F2 is not. */
10427 if (ref_conv1
&& ref_conv2
)
10429 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10430 && (ref_conv1
->rvaluedness_matches_p
10431 != ref_conv2
->rvaluedness_matches_p
)
10432 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10433 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10434 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10436 if (ref_conv1
->bad_p
10437 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10438 TREE_TYPE (ref_conv2
->type
)))
10439 /* Don't prefer a bad conversion that drops cv-quals to a bad
10440 conversion with the wrong rvalueness. */
10442 return (ref_conv1
->rvaluedness_matches_p
10443 - ref_conv2
->rvaluedness_matches_p
);
10446 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10448 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10449 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10450 if (ref_conv1
->bad_p
)
10452 /* Prefer the one that drops fewer cv-quals. */
10453 tree ftype
= next_conversion (ref_conv1
)->type
;
10454 int fquals
= cp_type_quals (ftype
);
10458 return comp_cv_qualification (q2
, q1
);
10462 /* Neither conversion sequence is better than the other. */
10466 /* The source type for this standard conversion sequence. */
10469 source_type (conversion
*t
)
10471 for (;; t
= next_conversion (t
))
10473 if (t
->kind
== ck_user
10474 || t
->kind
== ck_ambig
10475 || t
->kind
== ck_identity
)
10478 gcc_unreachable ();
10481 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10482 a pointer to LOSER and re-running joust to produce the warning if WINNER
10483 is actually used. */
10486 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10488 candidate_warning
*cw
= (candidate_warning
*)
10489 conversion_obstack_alloc (sizeof (candidate_warning
));
10491 cw
->next
= winner
->warnings
;
10492 winner
->warnings
= cw
;
10495 /* CAND is a constructor candidate in joust in C++17 and up. If it copies a
10496 prvalue returned from a conversion function, replace CAND with the candidate
10497 for the conversion and return true. Otherwise, return false. */
10500 joust_maybe_elide_copy (z_candidate
*&cand
)
10502 tree fn
= cand
->fn
;
10503 if (!DECL_COPY_CONSTRUCTOR_P (fn
) && !DECL_MOVE_CONSTRUCTOR_P (fn
))
10505 conversion
*conv
= cand
->convs
[0];
10506 gcc_checking_assert (conv
->kind
== ck_ref_bind
);
10507 conv
= next_conversion (conv
);
10508 if (conv
->kind
== ck_user
&& !TYPE_REF_P (conv
->type
))
10510 gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p
10511 (conv
->type
, DECL_CONTEXT (fn
)));
10512 z_candidate
*uc
= conv
->cand
;
10513 if (DECL_CONV_FN_P (uc
->fn
))
10522 /* Compare two candidates for overloading as described in
10523 [over.match.best]. Return values:
10525 1: cand1 is better than cand2
10526 -1: cand2 is better than cand1
10527 0: cand1 and cand2 are indistinguishable */
10530 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10531 tsubst_flags_t complain
)
10534 int off1
= 0, off2
= 0;
10538 /* Candidates that involve bad conversions are always worse than those
10540 if (cand1
->viable
> cand2
->viable
)
10542 if (cand1
->viable
< cand2
->viable
)
10545 /* If we have two pseudo-candidates for conversions to the same type,
10546 or two candidates for the same function, arbitrarily pick one. */
10547 if (cand1
->fn
== cand2
->fn
10548 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10551 /* Prefer a non-deleted function over an implicitly deleted move
10552 constructor or assignment operator. This differs slightly from the
10553 wording for issue 1402 (which says the move op is ignored by overload
10554 resolution), but this way produces better error messages. */
10555 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10556 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10557 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10559 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10560 && move_fn_p (cand1
->fn
))
10562 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10563 && move_fn_p (cand2
->fn
))
10567 /* a viable function F1
10568 is defined to be a better function than another viable function F2 if
10569 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10570 ICSi(F2), and then */
10572 /* for some argument j, ICSj(F1) is a better conversion sequence than
10575 /* For comparing static and non-static member functions, we ignore
10576 the implicit object parameter of the non-static function. The
10577 standard says to pretend that the static function has an object
10578 parm, but that won't work with operator overloading. */
10579 len
= cand1
->num_convs
;
10580 if (len
!= cand2
->num_convs
)
10582 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10583 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10585 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10586 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10587 /* We're comparing a near-match list constructor and a near-match
10588 non-list constructor. Just treat them as unordered. */
10591 gcc_assert (static_1
!= static_2
);
10602 /* Handle C++17 copy elision in [over.match.ctor] (direct-init) context. The
10603 standard currently says that only constructors are candidates, but if one
10604 copies a prvalue returned by a conversion function we want to treat the
10605 conversion as the candidate instead.
10607 Clang does something similar, as discussed at
10608 http://lists.isocpp.org/core/2017/10/3166.php
10609 http://lists.isocpp.org/core/2019/03/5721.php */
10610 int elided_tiebreaker
= 0;
10611 if (len
== 1 && cxx_dialect
>= cxx17
10612 && DECL_P (cand1
->fn
)
10613 && DECL_COMPLETE_CONSTRUCTOR_P (cand1
->fn
)
10614 && !(cand1
->flags
& LOOKUP_ONLYCONVERTING
))
10616 bool elided1
= joust_maybe_elide_copy (cand1
);
10617 bool elided2
= joust_maybe_elide_copy (cand2
);
10618 /* As a tiebreaker below we will prefer a constructor to a conversion
10619 operator exposed this way. */
10620 elided_tiebreaker
= elided2
- elided1
;
10623 for (i
= 0; i
< len
; ++i
)
10625 conversion
*t1
= cand1
->convs
[i
+ off1
];
10626 conversion
*t2
= cand2
->convs
[i
+ off2
];
10627 int comp
= compare_ics (t1
, t2
);
10631 if ((complain
& tf_warning
)
10633 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10634 == cr_std
+ cr_promotion
)
10635 && t1
->kind
== ck_std
10636 && t2
->kind
== ck_std
10637 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10638 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10639 && (TYPE_PRECISION (t1
->type
)
10640 == TYPE_PRECISION (t2
->type
))
10641 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10642 || (TREE_CODE (next_conversion (t1
)->type
)
10643 == ENUMERAL_TYPE
)))
10645 tree type
= next_conversion (t1
)->type
;
10647 struct z_candidate
*w
, *l
;
10649 type1
= t1
->type
, type2
= t2
->type
,
10650 w
= cand1
, l
= cand2
;
10652 type1
= t2
->type
, type2
= t1
->type
,
10653 w
= cand2
, l
= cand1
;
10657 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10658 type
, type1
, type2
);
10659 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10662 add_warning (w
, l
);
10665 if (winner
&& comp
!= winner
)
10674 /* warn about confusing overload resolution for user-defined conversions,
10675 either between a constructor and a conversion op, or between two
10677 if ((complain
& tf_warning
)
10678 && winner
&& warn_conversion
&& cand1
->second_conv
10679 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10680 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10682 struct z_candidate
*w
, *l
;
10683 bool give_warning
= false;
10686 w
= cand1
, l
= cand2
;
10688 w
= cand2
, l
= cand1
;
10690 /* We don't want to complain about `X::operator T1 ()'
10691 beating `X::operator T2 () const', when T2 is a no less
10692 cv-qualified version of T1. */
10693 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10694 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10696 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10697 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10699 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10704 if (!comp_ptr_ttypes (t
, f
))
10705 give_warning
= true;
10708 give_warning
= true;
10714 tree source
= source_type (w
->convs
[0]);
10715 if (INDIRECT_TYPE_P (source
))
10716 source
= TREE_TYPE (source
);
10717 auto_diagnostic_group d
;
10718 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10719 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10720 source
, w
->second_conv
->type
))
10722 inform (input_location
, " because conversion sequence "
10723 "for the argument is better");
10727 add_warning (w
, l
);
10733 /* Put this tiebreaker first, so that we don't try to look at second_conv of
10734 a constructor candidate that doesn't have one. */
10735 if (elided_tiebreaker
)
10736 return elided_tiebreaker
;
10738 /* DR 495 moved this tiebreaker above the template ones. */
10739 /* or, if not that,
10740 the context is an initialization by user-defined conversion (see
10741 _dcl.init_ and _over.match.user_) and the standard conversion
10742 sequence from the return type of F1 to the destination type (i.e.,
10743 the type of the entity being initialized) is a better conversion
10744 sequence than the standard conversion sequence from the return type
10745 of F2 to the destination type. */
10747 if (cand1
->second_conv
)
10749 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10754 /* or, if not that,
10755 F1 is a non-template function and F2 is a template function
10758 if (!cand1
->template_decl
&& cand2
->template_decl
)
10760 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10763 /* or, if not that,
10764 F1 and F2 are template functions and the function template for F1 is
10765 more specialized than the template for F2 according to the partial
10768 if (cand1
->template_decl
&& cand2
->template_decl
)
10770 winner
= more_specialized_fn
10771 (TI_TEMPLATE (cand1
->template_decl
),
10772 TI_TEMPLATE (cand2
->template_decl
),
10773 /* [temp.func.order]: The presence of unused ellipsis and default
10774 arguments has no effect on the partial ordering of function
10775 templates. add_function_candidate() will not have
10776 counted the "this" argument for constructors. */
10777 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10783 // or, if not that, F1 is more constrained than F2.
10784 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10786 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10791 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10792 if (deduction_guide_p (cand1
->fn
))
10794 gcc_assert (deduction_guide_p (cand2
->fn
));
10795 /* We distinguish between candidates from an explicit deduction guide and
10796 candidates built from a constructor based on DECL_ARTIFICIAL. */
10797 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10798 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10800 return art2
- art1
;
10804 /* Prefer the special copy guide over a declared copy/move
10806 if (copy_guide_p (cand1
->fn
))
10808 if (copy_guide_p (cand2
->fn
))
10811 /* Prefer a candidate generated from a non-template constructor. */
10812 int tg1
= template_guide_p (cand1
->fn
);
10813 int tg2
= template_guide_p (cand2
->fn
);
10819 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10820 for all arguments the corresponding parameters of F1 and F2 have the same
10821 type (CWG 2273/2277). */
10822 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10823 && !DECL_CONV_FN_P (cand1
->fn
)
10824 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10825 && !DECL_CONV_FN_P (cand2
->fn
))
10827 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10828 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10830 bool used1
= false;
10831 bool used2
= false;
10832 if (base1
== base2
)
10833 /* No difference. */;
10834 else if (DERIVED_FROM_P (base1
, base2
))
10836 else if (DERIVED_FROM_P (base2
, base1
))
10839 if (int diff
= used2
- used1
)
10841 for (i
= 0; i
< len
; ++i
)
10843 conversion
*t1
= cand1
->convs
[i
+ off1
];
10844 conversion
*t2
= cand2
->convs
[i
+ off2
];
10845 if (!same_type_p (t1
->type
, t2
->type
))
10853 /* Check whether we can discard a builtin candidate, either because we
10854 have two identical ones or matching builtin and non-builtin candidates.
10856 (Pedantically in the latter case the builtin which matched the user
10857 function should not be added to the overload set, but we spot it here.
10860 ... the builtin candidates include ...
10861 - do not have the same parameter type list as any non-template
10862 non-member candidate. */
10864 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10866 for (i
= 0; i
< len
; ++i
)
10867 if (!same_type_p (cand1
->convs
[i
]->type
,
10868 cand2
->convs
[i
]->type
))
10870 if (i
== cand1
->num_convs
)
10872 if (cand1
->fn
== cand2
->fn
)
10873 /* Two built-in candidates; arbitrarily pick one. */
10875 else if (identifier_p (cand1
->fn
))
10876 /* cand1 is built-in; prefer cand2. */
10879 /* cand2 is built-in; prefer cand1. */
10884 /* For candidates of a multi-versioned function, make the version with
10885 the highest priority win. This version will be checked for dispatching
10886 first. If this version can be inlined into the caller, the front-end
10887 will simply make a direct call to this function. */
10889 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10890 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10891 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10892 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10894 tree f1
= TREE_TYPE (cand1
->fn
);
10895 tree f2
= TREE_TYPE (cand2
->fn
);
10896 tree p1
= TYPE_ARG_TYPES (f1
);
10897 tree p2
= TYPE_ARG_TYPES (f2
);
10899 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10900 is possible that cand1->fn and cand2->fn are function versions but of
10901 different functions. Check types to see if they are versions of the same
10903 if (compparms (p1
, p2
)
10904 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10906 /* Always make the version with the higher priority, more
10907 specialized, win. */
10908 gcc_assert (targetm
.compare_version_priority
);
10909 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10916 /* If the two function declarations represent the same function (this can
10917 happen with declarations in multiple scopes and arg-dependent lookup),
10918 arbitrarily choose one. But first make sure the default args we're
10920 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10921 && equal_functions (cand1
->fn
, cand2
->fn
))
10923 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10924 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10926 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10928 for (i
= 0; i
< len
; ++i
)
10930 /* Don't crash if the fn is variadic. */
10933 parms1
= TREE_CHAIN (parms1
);
10934 parms2
= TREE_CHAIN (parms2
);
10938 parms1
= TREE_CHAIN (parms1
);
10940 parms2
= TREE_CHAIN (parms2
);
10942 for (; parms1
; ++i
)
10944 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10945 TREE_PURPOSE (parms2
)))
10949 if (complain
& tf_error
)
10951 auto_diagnostic_group d
;
10952 if (permerror (input_location
,
10953 "default argument mismatch in "
10954 "overload resolution"))
10956 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10957 " candidate 1: %q#F", cand1
->fn
);
10958 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10959 " candidate 2: %q#F", cand2
->fn
);
10966 add_warning (cand1
, cand2
);
10969 parms1
= TREE_CHAIN (parms1
);
10970 parms2
= TREE_CHAIN (parms2
);
10978 /* Extension: If the worst conversion for one candidate is better than the
10979 worst conversion for the other, take the first. */
10980 if (!pedantic
&& (complain
& tf_warning_or_error
))
10982 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
10983 struct z_candidate
*w
= 0, *l
= 0;
10985 for (i
= 0; i
< len
; ++i
)
10987 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
10988 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
10989 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
10990 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
10993 winner
= 1, w
= cand1
, l
= cand2
;
10995 winner
= -1, w
= cand2
, l
= cand1
;
10998 /* Don't choose a deleted function over ambiguity. */
10999 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
11003 auto_diagnostic_group d
;
11004 if (pedwarn (input_location
, 0,
11005 "ISO C++ says that these are ambiguous, even "
11006 "though the worst conversion for the first is "
11007 "better than the worst conversion for the second:"))
11009 print_z_candidate (input_location
, N_("candidate 1:"), w
);
11010 print_z_candidate (input_location
, N_("candidate 2:"), l
);
11014 add_warning (w
, l
);
11019 gcc_assert (!winner
);
11023 /* Given a list of candidates for overloading, find the best one, if any.
11024 This algorithm has a worst case of O(2n) (winner is last), and a best
11025 case of O(n/2) (totally ambiguous); much better than a sorting
11028 static struct z_candidate
*
11029 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
11031 struct z_candidate
*champ
= candidates
, *challenger
;
11033 int champ_compared_to_predecessor
= 0;
11035 /* Walk through the list once, comparing each current champ to the next
11036 candidate, knocking out a candidate or two with each comparison. */
11038 for (challenger
= champ
->next
; challenger
; )
11040 fate
= joust (champ
, challenger
, 0, complain
);
11042 challenger
= challenger
->next
;
11047 champ
= challenger
->next
;
11050 champ_compared_to_predecessor
= 0;
11054 champ
= challenger
;
11055 champ_compared_to_predecessor
= 1;
11058 challenger
= champ
->next
;
11062 /* Make sure the champ is better than all the candidates it hasn't yet
11063 been compared to. */
11065 for (challenger
= candidates
;
11066 challenger
!= champ
11067 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
11068 challenger
= challenger
->next
)
11070 fate
= joust (champ
, challenger
, 0, complain
);
11078 /* Returns nonzero if things of type FROM can be converted to TO. */
11081 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
11083 tree arg
= NULL_TREE
;
11084 /* implicit_conversion only considers user-defined conversions
11085 if it has an expression for the call argument list. */
11086 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
11087 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
11088 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
11091 /* Returns nonzero if things of type FROM can be converted to TO with a
11092 standard conversion. */
11095 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
11097 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
11100 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
11103 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
11104 tsubst_flags_t complain
)
11110 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11111 p
= conversion_obstack_alloc (0);
11112 /* We want to discard any access checks done for this test,
11113 as we might not be in the appropriate access context and
11114 we'll do the check again when we actually perform the
11116 push_deferring_access_checks (dk_deferred
);
11118 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11120 ok_p
= (t
&& !t
->bad_p
);
11122 /* Discard the access checks now. */
11123 pop_deferring_access_checks ();
11124 /* Free all the conversions we allocated. */
11125 obstack_free (&conversion_obstack
, p
);
11130 /* Like can_convert_arg, but allows dubious conversions as well. */
11133 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
11134 tsubst_flags_t complain
)
11139 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11140 p
= conversion_obstack_alloc (0);
11141 /* Try to perform the conversion. */
11142 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11144 /* Free all the conversions we allocated. */
11145 obstack_free (&conversion_obstack
, p
);
11150 /* Convert EXPR to TYPE. Return the converted expression.
11152 Note that we allow bad conversions here because by the time we get to
11153 this point we are committed to doing the conversion. If we end up
11154 doing a bad conversion, convert_like will complain. */
11157 perform_implicit_conversion_flags (tree type
, tree expr
,
11158 tsubst_flags_t complain
, int flags
)
11162 location_t loc
= cp_expr_loc_or_input_loc (expr
);
11164 if (TYPE_REF_P (type
))
11165 expr
= mark_lvalue_use (expr
);
11167 expr
= mark_rvalue_use (expr
);
11169 if (error_operand_p (expr
))
11170 return error_mark_node
;
11172 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11173 p
= conversion_obstack_alloc (0);
11175 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11176 /*c_cast_p=*/false,
11181 if (complain
& tf_error
)
11183 /* If expr has unknown type, then it is an overloaded function.
11184 Call instantiate_type to get good error messages. */
11185 if (TREE_TYPE (expr
) == unknown_type_node
)
11186 instantiate_type (type
, expr
, complain
);
11187 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
11188 /* We gave an error. */;
11191 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
11192 gcc_rich_location
rich_loc (loc
, &label
);
11193 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
11194 expr
, TREE_TYPE (expr
), type
);
11197 expr
= error_mark_node
;
11199 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11201 /* In a template, we are only concerned about determining the
11202 type of non-dependent expressions, so we do not have to
11203 perform the actual conversion. But for initializers, we
11204 need to be able to perform it at instantiation
11205 (or instantiate_non_dependent_expr) time. */
11206 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11207 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11208 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11209 if (flags
& LOOKUP_NO_NARROWING
)
11210 IMPLICIT_CONV_EXPR_BRACED_INIT (expr
) = true;
11213 expr
= convert_like (conv
, expr
, complain
);
11215 /* Free all the conversions we allocated. */
11216 obstack_free (&conversion_obstack
, p
);
11222 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11224 return perform_implicit_conversion_flags (type
, expr
, complain
,
11228 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11229 permitted. If the conversion is valid, the converted expression is
11230 returned. Otherwise, NULL_TREE is returned, except in the case
11231 that TYPE is a class type; in that case, an error is issued. If
11232 C_CAST_P is true, then this direct-initialization is taking
11233 place as part of a static_cast being attempted as part of a C-style
11237 perform_direct_initialization_if_possible (tree type
,
11240 tsubst_flags_t complain
)
11245 if (type
== error_mark_node
|| error_operand_p (expr
))
11246 return error_mark_node
;
11249 If the destination type is a (possibly cv-qualified) class type:
11251 -- If the initialization is direct-initialization ...,
11252 constructors are considered. ... If no constructor applies, or
11253 the overload resolution is ambiguous, the initialization is
11255 if (CLASS_TYPE_P (type
))
11257 releasing_vec
args (make_tree_vector_single (expr
));
11258 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11259 &args
, type
, LOOKUP_NORMAL
, complain
);
11260 return build_cplus_new (type
, expr
, complain
);
11263 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11264 p
= conversion_obstack_alloc (0);
11266 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11268 LOOKUP_NORMAL
, complain
);
11269 if (!conv
|| conv
->bad_p
)
11271 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11273 /* In a template, we are only concerned about determining the
11274 type of non-dependent expressions, so we do not have to
11275 perform the actual conversion. But for initializers, we
11276 need to be able to perform it at instantiation
11277 (or instantiate_non_dependent_expr) time. */
11278 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11279 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11282 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11283 /*issue_conversion_warnings=*/false,
11287 /* Free all the conversions we allocated. */
11288 obstack_free (&conversion_obstack
, p
);
11293 /* When initializing a reference that lasts longer than a full-expression,
11294 this special rule applies:
11298 The temporary to which the reference is bound or the temporary
11299 that is the complete object to which the reference is bound
11300 persists for the lifetime of the reference.
11302 The temporaries created during the evaluation of the expression
11303 initializing the reference, except the temporary to which the
11304 reference is bound, are destroyed at the end of the
11305 full-expression in which they are created.
11307 In that case, we store the converted expression into a new
11308 VAR_DECL in a new scope.
11310 However, we want to be careful not to create temporaries when
11311 they are not required. For example, given:
11314 struct D : public B {};
11318 there is no need to copy the return value from "f"; we can just
11319 extend its lifetime. Similarly, given:
11322 struct T { operator S(); };
11326 we can extend the lifetime of the return value of the conversion
11329 The next several functions are involved in this lifetime extension. */
11331 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11332 reference is being bound to a temporary. Create and return a new
11333 VAR_DECL with the indicated TYPE; this variable will store the value to
11334 which the reference is bound. */
11337 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11339 tree var
= create_temporary_var (type
);
11341 /* Register the variable. */
11343 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11345 /* Namespace-scope or local static; give it a mangled name. */
11347 /* If an initializer is visible to multiple translation units, those
11348 translation units must agree on the addresses of the
11349 temporaries. Therefore the temporaries must be given a consistent name
11350 and vague linkage. The mangled name of a temporary is the name of the
11351 non-temporary object in whose initializer they appear, prefixed with
11352 GR and suffixed with a sequence number mangled using the usual rules
11353 for a seq-id. Temporaries are numbered with a pre-order, depth-first,
11354 left-to-right walk of the complete initializer. */
11356 TREE_STATIC (var
) = TREE_STATIC (decl
);
11357 TREE_PUBLIC (var
) = TREE_PUBLIC (decl
);
11358 if (vague_linkage_p (decl
))
11359 comdat_linkage (var
);
11361 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11362 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11364 tree name
= mangle_ref_init_variable (decl
);
11365 DECL_NAME (var
) = name
;
11366 SET_DECL_ASSEMBLER_NAME (var
, name
);
11369 /* Create a new cleanup level if necessary. */
11370 maybe_push_cleanup_level (type
);
11372 return pushdecl (var
);
11375 /* EXPR is the initializer for a variable DECL of reference or
11376 std::initializer_list type. Create, push and return a new VAR_DECL
11377 for the initializer so that it will live as long as DECL. Any
11378 cleanup for the new variable is returned through CLEANUP, and the
11379 code to initialize the new variable is returned through INITP. */
11382 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11389 /* Create the temporary variable. */
11390 type
= TREE_TYPE (expr
);
11391 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11392 layout_decl (var
, 0);
11393 /* If the rvalue is the result of a function call it will be
11394 a TARGET_EXPR. If it is some other construct (such as a
11395 member access expression where the underlying object is
11396 itself the result of a function call), turn it into a
11397 TARGET_EXPR here. It is important that EXPR be a
11398 TARGET_EXPR below since otherwise the INIT_EXPR will
11399 attempt to make a bitwise copy of EXPR to initialize
11401 if (TREE_CODE (expr
) != TARGET_EXPR
)
11402 expr
= get_target_expr (expr
);
11404 if (TREE_CODE (decl
) == FIELD_DECL
11405 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11407 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11408 "until the constructor exits", decl
);
11409 TREE_NO_WARNING (decl
) = true;
11412 /* Recursively extend temps in this initializer. */
11413 TARGET_EXPR_INITIAL (expr
)
11414 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11416 /* Any reference temp has a non-trivial initializer. */
11417 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11419 /* If the initializer is constant, put it in DECL_INITIAL so we get
11420 static initialization and use in constant expressions. */
11421 init
= maybe_constant_init (expr
);
11422 /* As in store_init_value. */
11423 init
= cp_fully_fold (init
);
11424 if (TREE_CONSTANT (init
))
11426 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11428 /* 5.19 says that a constant expression can include an
11429 lvalue-rvalue conversion applied to "a glvalue of literal type
11430 that refers to a non-volatile temporary object initialized
11431 with a constant expression". Rather than try to communicate
11432 that this VAR_DECL is a temporary, just mark it constexpr. */
11433 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11434 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11435 TREE_CONSTANT (var
) = true;
11436 TREE_READONLY (var
) = true;
11438 DECL_INITIAL (var
) = init
;
11442 /* Create the INIT_EXPR that will initialize the temporary
11444 init
= split_nonconstant_init (var
, expr
);
11445 if (at_function_scope_p ())
11447 add_decl_expr (var
);
11449 if (TREE_STATIC (var
))
11450 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11453 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11455 vec_safe_push (*cleanups
, cleanup
);
11458 /* We must be careful to destroy the temporary only
11459 after its initialization has taken place. If the
11460 initialization throws an exception, then the
11461 destructor should not be run. We cannot simply
11462 transform INIT into something like:
11464 (INIT, ({ CLEANUP_STMT; }))
11466 because emit_local_var always treats the
11467 initializer as a full-expression. Thus, the
11468 destructor would run too early; it would run at the
11469 end of initializing the reference variable, rather
11470 than at the end of the block enclosing the
11471 reference variable.
11473 The solution is to pass back a cleanup expression
11474 which the caller is responsible for attaching to
11475 the statement tree. */
11479 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11480 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11482 if (CP_DECL_THREAD_LOCAL_P (var
))
11483 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11486 static_aggregates
= tree_cons (NULL_TREE
, var
,
11487 static_aggregates
);
11490 /* Check whether the dtor is callable. */
11491 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11493 /* Avoid -Wunused-variable warning (c++/38958). */
11494 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11496 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11502 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11503 initializing a variable of that TYPE. */
11506 initialize_reference (tree type
, tree expr
,
11507 int flags
, tsubst_flags_t complain
)
11511 location_t loc
= cp_expr_loc_or_input_loc (expr
);
11513 if (type
== error_mark_node
|| error_operand_p (expr
))
11514 return error_mark_node
;
11516 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11517 p
= conversion_obstack_alloc (0);
11519 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11521 if (!conv
|| conv
->bad_p
)
11523 if (complain
& tf_error
)
11526 convert_like (conv
, expr
, complain
);
11527 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11528 && !TYPE_REF_IS_RVALUE (type
)
11529 && !lvalue_p (expr
))
11530 error_at (loc
, "invalid initialization of non-const reference of "
11531 "type %qH from an rvalue of type %qI",
11532 type
, TREE_TYPE (expr
));
11534 error_at (loc
, "invalid initialization of reference of type "
11535 "%qH from expression of type %qI", type
,
11538 return error_mark_node
;
11541 if (conv
->kind
== ck_ref_bind
)
11542 /* Perform the conversion. */
11543 expr
= convert_like (conv
, expr
, complain
);
11544 else if (conv
->kind
== ck_ambig
)
11545 /* We gave an error in build_user_type_conversion_1. */
11546 expr
= error_mark_node
;
11548 gcc_unreachable ();
11550 /* Free all the conversions we allocated. */
11551 obstack_free (&conversion_obstack
, p
);
11556 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11557 which is bound either to a reference or a std::initializer_list. */
11560 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11565 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11567 TREE_OPERAND (sub
, 1)
11568 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11571 if (TREE_CODE (sub
) != ADDR_EXPR
)
11573 /* Deal with binding to a subobject. */
11574 for (p
= &TREE_OPERAND (sub
, 0);
11575 (TREE_CODE (*p
) == COMPONENT_REF
11576 || TREE_CODE (*p
) == ARRAY_REF
); )
11577 p
= &TREE_OPERAND (*p
, 0);
11578 if (TREE_CODE (*p
) == TARGET_EXPR
)
11580 tree subinit
= NULL_TREE
;
11581 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11582 recompute_tree_invariant_for_addr_expr (sub
);
11584 init
= fold_convert (TREE_TYPE (init
), sub
);
11586 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11591 /* INIT is part of the initializer for DECL. If there are any
11592 reference or initializer lists being initialized, extend their
11593 lifetime to match that of DECL. */
11596 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11598 tree type
= TREE_TYPE (init
);
11599 if (processing_template_decl
)
11601 if (TYPE_REF_P (type
))
11602 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11606 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11607 ctor
= TARGET_EXPR_INITIAL (ctor
);
11608 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11610 if (is_std_init_list (type
))
11612 /* The temporary array underlying a std::initializer_list
11613 is handled like a reference temporary. */
11614 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11615 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11616 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11621 constructor_elt
*p
;
11622 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11623 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11624 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11626 recompute_constructor_flags (ctor
);
11627 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11628 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11635 /* Returns true iff an initializer for TYPE could contain temporaries that
11636 need to be extended because they are bound to references or
11637 std::initializer_list. */
11640 type_has_extended_temps (tree type
)
11642 type
= strip_array_types (type
);
11643 if (TYPE_REF_P (type
))
11645 if (CLASS_TYPE_P (type
))
11647 if (is_std_init_list (type
))
11649 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11650 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11651 if (type_has_extended_temps (TREE_TYPE (f
)))
11657 /* Returns true iff TYPE is some variant of std::initializer_list. */
11660 is_std_init_list (tree type
)
11662 if (!TYPE_P (type
))
11664 if (cxx_dialect
== cxx98
)
11666 /* Look through typedefs. */
11667 type
= TYPE_MAIN_VARIANT (type
);
11668 return (CLASS_TYPE_P (type
)
11669 && CP_TYPE_CONTEXT (type
) == std_node
11670 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11673 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11674 will accept an argument list of a single std::initializer_list<T>. */
11677 is_list_ctor (tree decl
)
11679 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11682 if (!args
|| args
== void_list_node
)
11685 arg
= non_reference (TREE_VALUE (args
));
11686 if (!is_std_init_list (arg
))
11689 args
= TREE_CHAIN (args
);
11691 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11692 /* There are more non-defaulted parms. */
11698 #include "gt-cp-call.h"