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. You can
126 use conv_get_original_expr to get this expression. */
128 /* The array of conversions for an initializer_list, so this
129 variant is used only when KIN D is ck_list. */
132 /* The function candidate corresponding to this conversion
133 sequence. This field is only used if KIND is ck_user. */
134 struct z_candidate
*cand
;
137 #define CONVERSION_RANK(NODE) \
138 ((NODE)->bad_p ? cr_bad \
139 : (NODE)->ellipsis_p ? cr_ellipsis \
140 : (NODE)->user_conv_p ? cr_user \
143 #define BAD_CONVERSION_RANK(NODE) \
144 ((NODE)->ellipsis_p ? cr_ellipsis \
145 : (NODE)->user_conv_p ? cr_user \
148 static struct obstack conversion_obstack
;
149 static bool conversion_obstack_initialized
;
150 struct rejection_reason
;
152 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
153 static int equal_functions (tree
, tree
);
154 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
156 static int compare_ics (conversion
*, conversion
*);
157 static void maybe_warn_class_memaccess (location_t
, tree
,
158 const vec
<tree
, va_gc
> *);
159 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
160 #define convert_like(CONV, EXPR, COMPLAIN) \
161 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \
162 /*issue_conversion_warnings=*/true, \
163 /*c_cast_p=*/false, (COMPLAIN))
164 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
165 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \
166 /*issue_conversion_warnings=*/true, \
167 /*c_cast_p=*/false, (COMPLAIN))
168 static tree
convert_like_real (conversion
*, tree
, tree
, int, bool,
169 bool, tsubst_flags_t
);
170 static void op_error (const op_location_t
&, enum tree_code
, enum tree_code
,
171 tree
, tree
, tree
, bool);
172 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
174 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
175 static void print_z_candidates (location_t
, struct z_candidate
*);
176 static tree
build_this (tree
);
177 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
178 static bool any_strictly_viable (struct z_candidate
*);
179 static struct z_candidate
*add_template_candidate
180 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
181 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
182 static struct z_candidate
*add_template_candidate_real
183 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
184 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
185 static void add_builtin_candidates
186 (struct z_candidate
**, enum tree_code
, enum tree_code
,
187 tree
, tree
*, int, tsubst_flags_t
);
188 static void add_builtin_candidate
189 (struct z_candidate
**, enum tree_code
, enum tree_code
,
190 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
191 static bool is_complete (tree
);
192 static void build_builtin_candidate
193 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
194 int, tsubst_flags_t
);
195 static struct z_candidate
*add_conv_candidate
196 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
197 tree
, tsubst_flags_t
);
198 static struct z_candidate
*add_function_candidate
199 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
200 tree
, int, conversion
**, tsubst_flags_t
);
201 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
203 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
205 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
206 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
207 static conversion
*next_conversion (conversion
*);
208 static bool is_subseq (conversion
*, conversion
*);
209 static conversion
*maybe_handle_ref_bind (conversion
**);
210 static void maybe_handle_implicit_object (conversion
**);
211 static struct z_candidate
*add_candidate
212 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
213 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
214 static tree
source_type (conversion
*);
215 static void add_warning (struct z_candidate
*, struct z_candidate
*);
216 static bool reference_compatible_p (tree
, tree
);
217 static conversion
*direct_reference_binding (tree
, conversion
*);
218 static bool promoted_arithmetic_type_p (tree
);
219 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
220 static char *name_as_c_string (tree
, tree
, bool *);
221 static tree
prep_operand (tree
);
222 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
223 bool, tree
, tree
, int, struct z_candidate
**,
225 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
226 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
227 static conversion
*build_identity_conv (tree
, tree
);
228 static inline bool conv_binds_to_array_of_unknown_bound (conversion
*);
230 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
231 NAME can take many forms... */
234 check_dtor_name (tree basetype
, tree name
)
236 /* Just accept something we've already complained about. */
237 if (name
== error_mark_node
)
240 if (TREE_CODE (name
) == TYPE_DECL
)
241 name
= TREE_TYPE (name
);
242 else if (TYPE_P (name
))
244 else if (identifier_p (name
))
246 if ((MAYBE_CLASS_TYPE_P (basetype
)
247 || TREE_CODE (basetype
) == ENUMERAL_TYPE
)
248 && name
== constructor_name (basetype
))
251 name
= get_type_value (name
);
257 template <class T> struct S { ~S(); };
261 NAME will be a class template. */
262 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
266 if (!name
|| name
== error_mark_node
)
268 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
271 /* We want the address of a function or method. We avoid creating a
272 pointer-to-member function. */
275 build_addr_func (tree function
, tsubst_flags_t complain
)
277 tree type
= TREE_TYPE (function
);
279 /* We have to do these by hand to avoid real pointer to member
281 if (TREE_CODE (type
) == METHOD_TYPE
)
283 if (TREE_CODE (function
) == OFFSET_REF
)
285 tree object
= build_address (TREE_OPERAND (function
, 0));
286 return get_member_function_from_ptrfunc (&object
,
287 TREE_OPERAND (function
, 1),
290 function
= build_address (function
);
293 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
298 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
299 POINTER_TYPE to those. Note, pointer to member function types
300 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
301 two variants. build_call_a is the primitive taking an array of
302 arguments, while build_call_n is a wrapper that handles varargs. */
305 build_call_n (tree function
, int n
, ...)
308 return build_call_a (function
, 0, NULL
);
311 tree
*argarray
= XALLOCAVEC (tree
, n
);
316 for (i
= 0; i
< n
; i
++)
317 argarray
[i
] = va_arg (ap
, tree
);
319 return build_call_a (function
, n
, argarray
);
323 /* Update various flags in cfun and the call itself based on what is being
324 called. Split out of build_call_a so that bot_manip can use it too. */
327 set_flags_from_callee (tree call
)
329 /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */
330 tree decl
= cp_get_callee_fndecl_nofold (call
);
332 /* We check both the decl and the type; a function may be known not to
333 throw without being declared throw(). */
334 bool nothrow
= decl
&& TREE_NOTHROW (decl
);
335 tree callee
= cp_get_callee (call
);
337 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (callee
)));
338 else if (TREE_CODE (call
) == CALL_EXPR
339 && internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
342 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
343 cp_function_chain
->can_throw
= 1;
345 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
346 current_function_returns_abnormally
= 1;
348 TREE_NOTHROW (call
) = nothrow
;
352 build_call_a (tree function
, int n
, tree
*argarray
)
359 function
= build_addr_func (function
, tf_warning_or_error
);
361 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
362 fntype
= TREE_TYPE (TREE_TYPE (function
));
363 gcc_assert (FUNC_OR_METHOD_TYPE_P (fntype
));
364 result_type
= TREE_TYPE (fntype
);
365 /* An rvalue has no cv-qualifiers. */
366 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
367 result_type
= cv_unqualified (result_type
);
369 function
= build_call_array_loc (input_location
,
370 result_type
, function
, n
, argarray
);
371 set_flags_from_callee (function
);
373 decl
= get_callee_fndecl (function
);
375 if (decl
&& !TREE_USED (decl
))
377 /* We invoke build_call directly for several library
378 functions. These may have been declared normally if
379 we're building libgcc, so we can't just check
381 gcc_assert (DECL_ARTIFICIAL (decl
)
382 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
387 require_complete_eh_spec_types (fntype
, decl
);
389 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
391 /* Don't pass empty class objects by value. This is useful
392 for tags in STL, which are used to control overload resolution.
393 We don't need to handle other cases of copying empty classes. */
394 if (!decl
|| !fndecl_built_in_p (decl
))
395 for (i
= 0; i
< n
; i
++)
397 tree arg
= CALL_EXPR_ARG (function
, i
);
398 if (is_empty_class (TREE_TYPE (arg
))
399 && simple_empty_class_p (TREE_TYPE (arg
), arg
, INIT_EXPR
))
401 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
402 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
403 CALL_EXPR_ARG (function
, i
) = arg
;
410 /* New overloading code. */
414 struct candidate_warning
{
416 candidate_warning
*next
;
419 /* Information for providing diagnostics about why overloading failed. */
421 enum rejection_reason_code
{
424 rr_explicit_conversion
,
425 rr_template_conversion
,
427 rr_bad_arg_conversion
,
428 rr_template_unification
,
431 rr_constraint_failure
434 struct conversion_info
{
435 /* The index of the argument, 0-based. */
437 /* The actual argument or its type. */
439 /* The type of the parameter. */
441 /* The location of the argument. */
445 struct rejection_reason
{
446 enum rejection_reason_code code
;
448 /* Information about an arity mismatch. */
450 /* The expected number of arguments. */
452 /* The actual number of arguments in the call. */
454 /* Whether the call was a varargs call. */
457 /* Information about an argument conversion mismatch. */
458 struct conversion_info conversion
;
459 /* Same, but for bad argument conversions. */
460 struct conversion_info bad_conversion
;
461 /* Information about template unification failures. These are the
462 parameters passed to fn_type_unification. */
470 unification_kind_t strict
;
472 } template_unification
;
473 /* Information about template instantiation failures. These are the
474 parameters passed to instantiate_template. */
478 } template_instantiation
;
483 /* The FUNCTION_DECL that will be called if this candidate is
484 selected by overload resolution. */
486 /* If not NULL_TREE, the first argument to use when calling this
489 /* The rest of the arguments to use when calling this function. If
490 there are no further arguments this may be NULL or it may be an
492 const vec
<tree
, va_gc
> *args
;
493 /* The implicit conversion sequences for each of the arguments to
496 /* The number of implicit conversion sequences. */
498 /* If FN is a user-defined conversion, the standard conversion
499 sequence from the type returned by FN to the desired destination
501 conversion
*second_conv
;
502 struct rejection_reason
*reason
;
503 /* If FN is a member function, the binfo indicating the path used to
504 qualify the name of FN at the call site. This path is used to
505 determine whether or not FN is accessible if it is selected by
506 overload resolution. The DECL_CONTEXT of FN will always be a
507 (possibly improper) base of this binfo. */
509 /* If FN is a non-static member function, the binfo indicating the
510 subobject to which the `this' pointer should be converted if FN
511 is selected by overload resolution. The type pointed to by
512 the `this' pointer must correspond to the most derived class
513 indicated by the CONVERSION_PATH. */
514 tree conversion_path
;
517 candidate_warning
*warnings
;
521 /* The flags active in add_candidate. */
525 /* Returns true iff T is a null pointer constant in the sense of
529 null_ptr_cst_p (tree t
)
531 tree type
= TREE_TYPE (t
);
535 A null pointer constant is an integer literal ([lex.icon]) with value
536 zero or a prvalue of type std::nullptr_t. */
537 if (NULLPTR_TYPE_P (type
))
540 if (cxx_dialect
>= cxx11
)
542 STRIP_ANY_LOCATION_WRAPPER (t
);
544 /* Core issue 903 says only literal 0 is a null pointer constant. */
545 if (TREE_CODE (t
) == INTEGER_CST
546 && !TREE_OVERFLOW (t
)
547 && TREE_CODE (type
) == INTEGER_TYPE
549 && !char_type_p (type
))
552 else if (CP_INTEGRAL_TYPE_P (type
))
554 t
= fold_non_dependent_expr (t
, tf_none
);
556 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
563 /* Returns true iff T is a null member pointer value (4.11). */
566 null_member_pointer_value_p (tree t
)
568 tree type
= TREE_TYPE (t
);
571 else if (TYPE_PTRMEMFUNC_P (type
))
572 return (TREE_CODE (t
) == CONSTRUCTOR
573 && CONSTRUCTOR_NELTS (t
)
574 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
575 else if (TYPE_PTRDATAMEM_P (type
))
576 return integer_all_onesp (t
);
581 /* Returns nonzero if PARMLIST consists of only default parms,
582 ellipsis, and/or undeduced parameter packs. */
585 sufficient_parms_p (const_tree parmlist
)
587 for (; parmlist
&& parmlist
!= void_list_node
;
588 parmlist
= TREE_CHAIN (parmlist
))
589 if (!TREE_PURPOSE (parmlist
)
590 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
595 /* Allocate N bytes of memory from the conversion obstack. The memory
596 is zeroed before being returned. */
599 conversion_obstack_alloc (size_t n
)
602 if (!conversion_obstack_initialized
)
604 gcc_obstack_init (&conversion_obstack
);
605 conversion_obstack_initialized
= true;
607 p
= obstack_alloc (&conversion_obstack
, n
);
612 /* Allocate rejection reasons. */
614 static struct rejection_reason
*
615 alloc_rejection (enum rejection_reason_code code
)
617 struct rejection_reason
*p
;
618 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
623 static struct rejection_reason
*
624 arity_rejection (tree first_arg
, int expected
, int actual
)
626 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
627 int adjust
= first_arg
!= NULL_TREE
;
628 r
->u
.arity
.expected
= expected
- adjust
;
629 r
->u
.arity
.actual
= actual
- adjust
;
633 static struct rejection_reason
*
634 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
637 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
638 int adjust
= first_arg
!= NULL_TREE
;
639 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
640 r
->u
.conversion
.from
= from
;
641 r
->u
.conversion
.to_type
= to
;
642 r
->u
.conversion
.loc
= loc
;
646 static struct rejection_reason
*
647 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
650 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
651 int adjust
= first_arg
!= NULL_TREE
;
652 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
653 r
->u
.bad_conversion
.from
= from
;
654 r
->u
.bad_conversion
.to_type
= to
;
655 r
->u
.bad_conversion
.loc
= loc
;
659 static struct rejection_reason
*
660 explicit_conversion_rejection (tree from
, tree to
)
662 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
663 r
->u
.conversion
.n_arg
= 0;
664 r
->u
.conversion
.from
= from
;
665 r
->u
.conversion
.to_type
= to
;
666 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
670 static struct rejection_reason
*
671 template_conversion_rejection (tree from
, tree to
)
673 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
674 r
->u
.conversion
.n_arg
= 0;
675 r
->u
.conversion
.from
= from
;
676 r
->u
.conversion
.to_type
= to
;
677 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
681 static struct rejection_reason
*
682 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
683 const tree
*args
, unsigned int nargs
,
684 tree return_type
, unification_kind_t strict
,
687 size_t args_n_bytes
= sizeof (*args
) * nargs
;
688 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
689 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
690 r
->u
.template_unification
.tmpl
= tmpl
;
691 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
692 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
693 /* Copy args to our own storage. */
694 memcpy (args1
, args
, args_n_bytes
);
695 r
->u
.template_unification
.args
= args1
;
696 r
->u
.template_unification
.nargs
= nargs
;
697 r
->u
.template_unification
.return_type
= return_type
;
698 r
->u
.template_unification
.strict
= strict
;
699 r
->u
.template_unification
.flags
= flags
;
703 static struct rejection_reason
*
704 template_unification_error_rejection (void)
706 return alloc_rejection (rr_template_unification
);
709 static struct rejection_reason
*
710 invalid_copy_with_fn_template_rejection (void)
712 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
716 static struct rejection_reason
*
717 inherited_ctor_rejection (void)
719 struct rejection_reason
*r
= alloc_rejection (rr_inherited_ctor
);
723 /* Build a constraint failure record. */
725 static struct rejection_reason
*
726 constraint_failure (void)
728 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
732 /* Dynamically allocate a conversion. */
735 alloc_conversion (conversion_kind kind
)
738 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
743 /* Make sure that all memory on the conversion obstack has been
747 validate_conversion_obstack (void)
749 if (conversion_obstack_initialized
)
750 gcc_assert ((obstack_next_free (&conversion_obstack
)
751 == obstack_base (&conversion_obstack
)));
754 /* Dynamically allocate an array of N conversions. */
757 alloc_conversions (size_t n
)
759 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
763 build_conv (conversion_kind code
, tree type
, conversion
*from
)
766 conversion_rank rank
= CONVERSION_RANK (from
);
768 /* Note that the caller is responsible for filling in t->cand for
769 user-defined conversions. */
770 t
= alloc_conversion (code
);
794 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
795 t
->bad_p
= from
->bad_p
;
800 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
801 specialization of std::initializer_list<T>, if such a conversion is
805 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
807 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
808 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
809 conversion
**subconvs
= alloc_conversions (len
);
814 /* Within a list-initialization we can have more user-defined
816 flags
&= ~LOOKUP_NO_CONVERSION
;
817 /* But no narrowing conversions. */
818 flags
|= LOOKUP_NO_NARROWING
;
820 /* Can't make an array of these types. */
821 if (TYPE_REF_P (elttype
)
822 || TREE_CODE (elttype
) == FUNCTION_TYPE
823 || VOID_TYPE_P (elttype
))
826 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
829 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
830 false, flags
, complain
);
837 t
= alloc_conversion (ck_list
);
839 t
->u
.list
= subconvs
;
842 for (i
= 0; i
< len
; ++i
)
844 conversion
*sub
= subconvs
[i
];
845 if (sub
->rank
> t
->rank
)
847 if (sub
->user_conv_p
)
848 t
->user_conv_p
= true;
856 /* Return the next conversion of the conversion chain (if applicable),
857 or NULL otherwise. Please use this function instead of directly
858 accessing fields of struct conversion. */
861 next_conversion (conversion
*conv
)
864 || conv
->kind
== ck_identity
865 || conv
->kind
== ck_ambig
866 || conv
->kind
== ck_list
)
871 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
872 is a valid aggregate initializer for array type ATYPE. */
875 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
878 tree elttype
= TREE_TYPE (atype
);
879 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
881 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
883 if (TREE_CODE (elttype
) == ARRAY_TYPE
884 && TREE_CODE (val
) == CONSTRUCTOR
)
885 ok
= can_convert_array (elttype
, val
, flags
, complain
);
887 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
895 /* Helper for build_aggr_conv. Return true if FIELD is in PSET, or if
896 FIELD has ANON_AGGR_TYPE_P and any initializable field in there recursively
900 field_in_pset (hash_set
<tree
, true> &pset
, tree field
)
902 if (pset
.contains (field
))
904 if (ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
905 for (field
= TYPE_FIELDS (TREE_TYPE (field
));
906 field
; field
= DECL_CHAIN (field
))
908 field
= next_initializable_field (field
);
909 if (field
== NULL_TREE
)
911 if (field_in_pset (pset
, field
))
917 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
918 aggregate class, if such a conversion is possible. */
921 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
923 unsigned HOST_WIDE_INT i
= 0;
925 tree field
= next_initializable_field (TYPE_FIELDS (type
));
926 tree empty_ctor
= NULL_TREE
;
927 hash_set
<tree
, true> pset
;
929 /* We already called reshape_init in implicit_conversion. */
931 /* The conversions within the init-list aren't affected by the enclosing
932 context; they're always simple copy-initialization. */
933 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
935 /* For designated initializers, verify that each initializer is convertible
936 to corresponding TREE_TYPE (ce->index) and mark those FIELD_DECLs as
937 visited. In the following loop then ignore already visited
939 if (CONSTRUCTOR_IS_DESIGNATED_INIT (ctor
))
942 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (ctor
), i
, idx
, val
)
944 if (idx
&& TREE_CODE (idx
) == FIELD_DECL
)
946 tree ftype
= TREE_TYPE (idx
);
949 if (TREE_CODE (ftype
) == ARRAY_TYPE
950 && TREE_CODE (val
) == CONSTRUCTOR
)
951 ok
= can_convert_array (ftype
, val
, flags
, complain
);
953 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
958 /* For unions, there should be just one initializer. */
959 if (TREE_CODE (type
) == UNION_TYPE
)
972 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
974 tree ftype
= TREE_TYPE (field
);
978 if (!pset
.is_empty () && field_in_pset (pset
, field
))
980 if (i
< CONSTRUCTOR_NELTS (ctor
))
982 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
985 else if (DECL_INITIAL (field
))
986 val
= get_nsdmi (field
, /*ctor*/false, complain
);
987 else if (TYPE_REF_P (ftype
))
988 /* Value-initialization of reference is ill-formed. */
992 if (empty_ctor
== NULL_TREE
)
993 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
997 if (TREE_CODE (ftype
) == ARRAY_TYPE
998 && TREE_CODE (val
) == CONSTRUCTOR
)
999 ok
= can_convert_array (ftype
, val
, flags
, complain
);
1001 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
1007 if (TREE_CODE (type
) == UNION_TYPE
)
1011 if (i
< CONSTRUCTOR_NELTS (ctor
))
1014 c
= alloc_conversion (ck_aggr
);
1017 c
->user_conv_p
= true;
1018 c
->check_narrowing
= true;
1023 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
1024 array type, if such a conversion is possible. */
1027 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
1030 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1031 tree elttype
= TREE_TYPE (type
);
1036 enum conversion_rank rank
= cr_exact
;
1038 /* We might need to propagate the size from the element to the array. */
1039 complete_type (type
);
1041 if (TYPE_DOMAIN (type
)
1042 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
1044 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
1049 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1051 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1054 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1055 false, flags
, complain
);
1059 if (sub
->rank
> rank
)
1061 if (sub
->user_conv_p
)
1067 c
= alloc_conversion (ck_aggr
);
1070 c
->user_conv_p
= user
;
1072 c
->u
.next
= build_identity_conv (TREE_TYPE (ctor
), ctor
);
1076 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1077 complex type, if such a conversion is possible. */
1080 build_complex_conv (tree type
, tree ctor
, int flags
,
1081 tsubst_flags_t complain
)
1084 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1085 tree elttype
= TREE_TYPE (type
);
1090 enum conversion_rank rank
= cr_exact
;
1095 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1097 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1100 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1101 false, flags
, complain
);
1105 if (sub
->rank
> rank
)
1107 if (sub
->user_conv_p
)
1113 c
= alloc_conversion (ck_aggr
);
1116 c
->user_conv_p
= user
;
1122 /* Build a representation of the identity conversion from EXPR to
1123 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1126 build_identity_conv (tree type
, tree expr
)
1130 c
= alloc_conversion (ck_identity
);
1137 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1138 were multiple user-defined conversions to accomplish the job.
1139 Build a conversion that indicates that ambiguity. */
1142 build_ambiguous_conv (tree type
, tree expr
)
1146 c
= alloc_conversion (ck_ambig
);
1154 strip_top_quals (tree t
)
1156 if (TREE_CODE (t
) == ARRAY_TYPE
)
1158 return cp_build_qualified_type (t
, 0);
1161 /* Returns the standard conversion path (see [conv]) from type FROM to type
1162 TO, if any. For proper handling of null pointer constants, you must
1163 also pass the expression EXPR to convert from. If C_CAST_P is true,
1164 this conversion is coming from a C-style cast. */
1167 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1168 int flags
, tsubst_flags_t complain
)
1170 enum tree_code fcode
, tcode
;
1172 bool fromref
= false;
1175 to
= non_reference (to
);
1176 if (TYPE_REF_P (from
))
1179 from
= TREE_TYPE (from
);
1182 to
= strip_top_quals (to
);
1183 from
= strip_top_quals (from
);
1185 if (expr
&& type_unknown_p (expr
))
1187 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1189 tsubst_flags_t tflags
= tf_conv
;
1190 expr
= instantiate_type (to
, expr
, tflags
);
1191 if (expr
== error_mark_node
)
1193 from
= TREE_TYPE (expr
);
1195 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1197 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1198 expr
= resolve_nondeduced_context (expr
, complain
);
1199 from
= TREE_TYPE (expr
);
1203 fcode
= TREE_CODE (from
);
1204 tcode
= TREE_CODE (to
);
1206 conv
= build_identity_conv (from
, expr
);
1207 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1209 from
= type_decays_to (from
);
1210 fcode
= TREE_CODE (from
);
1211 /* Tell convert_like_real that we're using the address. */
1212 conv
->rvaluedness_matches_p
= true;
1213 conv
= build_conv (ck_lvalue
, from
, conv
);
1215 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1216 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1217 express the copy constructor call required by copy-initialization. */
1218 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1223 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1226 from
= strip_top_quals (bitfield_type
);
1227 fcode
= TREE_CODE (from
);
1230 conv
= build_conv (ck_rvalue
, from
, conv
);
1231 if (flags
& LOOKUP_PREFER_RVALUE
)
1232 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1233 conv
->rvaluedness_matches_p
= true;
1236 /* Allow conversion between `__complex__' data types. */
1237 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1239 /* The standard conversion sequence to convert FROM to TO is
1240 the standard conversion sequence to perform componentwise
1242 conversion
*part_conv
= standard_conversion
1243 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1248 conv
= build_conv (part_conv
->kind
, to
, conv
);
1249 conv
->rank
= part_conv
->rank
;
1257 if (same_type_p (from
, to
))
1259 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1260 conv
->type
= qualified_to
;
1265 A null pointer constant can be converted to a pointer type; ... A
1266 null pointer constant of integral type can be converted to an
1267 rvalue of type std::nullptr_t. */
1268 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1269 || NULLPTR_TYPE_P (to
))
1270 && ((expr
&& null_ptr_cst_p (expr
))
1271 || NULLPTR_TYPE_P (from
)))
1272 conv
= build_conv (ck_std
, to
, conv
);
1273 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1274 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1276 /* For backwards brain damage compatibility, allow interconversion of
1277 pointers and integers with a pedwarn. */
1278 conv
= build_conv (ck_std
, to
, conv
);
1281 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1283 /* For backwards brain damage compatibility, allow interconversion of
1284 enums and integers with a pedwarn. */
1285 conv
= build_conv (ck_std
, to
, conv
);
1288 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1289 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1294 if (tcode
== POINTER_TYPE
)
1296 to_pointee
= TREE_TYPE (to
);
1297 from_pointee
= TREE_TYPE (from
);
1299 /* Since this is the target of a pointer, it can't have function
1300 qualifiers, so any TYPE_QUALS must be for attributes const or
1301 noreturn. Strip them. */
1302 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1303 && TYPE_QUALS (to_pointee
))
1304 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1305 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1306 && TYPE_QUALS (from_pointee
))
1307 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1311 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1312 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1315 if (tcode
== POINTER_TYPE
1316 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1319 else if (VOID_TYPE_P (to_pointee
)
1320 && !TYPE_PTRDATAMEM_P (from
)
1321 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1323 tree nfrom
= TREE_TYPE (from
);
1324 /* Don't try to apply restrict to void. */
1325 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1326 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1327 from
= build_pointer_type (from_pointee
);
1328 conv
= build_conv (ck_ptr
, from
, conv
);
1330 else if (TYPE_PTRDATAMEM_P (from
))
1332 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1333 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1335 if (same_type_p (fbase
, tbase
))
1336 /* No base conversion needed. */;
1337 else if (DERIVED_FROM_P (fbase
, tbase
)
1338 && (same_type_ignoring_top_level_qualifiers_p
1339 (from_pointee
, to_pointee
)))
1341 from
= build_ptrmem_type (tbase
, from_pointee
);
1342 conv
= build_conv (ck_pmem
, from
, conv
);
1347 else if (CLASS_TYPE_P (from_pointee
)
1348 && CLASS_TYPE_P (to_pointee
)
1351 An rvalue of type "pointer to cv D," where D is a
1352 class type, can be converted to an rvalue of type
1353 "pointer to cv B," where B is a base class (clause
1354 _class.derived_) of D. If B is an inaccessible
1355 (clause _class.access_) or ambiguous
1356 (_class.member.lookup_) base class of D, a program
1357 that necessitates this conversion is ill-formed.
1358 Therefore, we use DERIVED_FROM_P, and do not check
1359 access or uniqueness. */
1360 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1363 = cp_build_qualified_type (to_pointee
,
1364 cp_type_quals (from_pointee
));
1365 from
= build_pointer_type (from_pointee
);
1366 conv
= build_conv (ck_ptr
, from
, conv
);
1367 conv
->base_p
= true;
1370 if (same_type_p (from
, to
))
1372 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
, bounds_either
))
1373 /* In a C-style cast, we ignore CV-qualification because we
1374 are allowed to perform a static_cast followed by a
1376 conv
= build_conv (ck_qual
, to
, conv
);
1377 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1378 conv
= build_conv (ck_qual
, to
, conv
);
1379 else if (expr
&& string_conv_p (to
, expr
, 0))
1380 /* converting from string constant to char *. */
1381 conv
= build_conv (ck_qual
, to
, conv
);
1382 else if (fnptr_conv_p (to
, from
))
1383 conv
= build_conv (ck_fnptr
, to
, conv
);
1384 /* Allow conversions among compatible ObjC pointer types (base
1385 conversions have been already handled above). */
1386 else if (c_dialect_objc ()
1387 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1388 conv
= build_conv (ck_ptr
, to
, conv
);
1389 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1391 conv
= build_conv (ck_ptr
, to
, conv
);
1399 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1401 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1402 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1403 tree fbase
= class_of_this_parm (fromfn
);
1404 tree tbase
= class_of_this_parm (tofn
);
1406 if (!DERIVED_FROM_P (fbase
, tbase
))
1409 tree fstat
= static_fn_type (fromfn
);
1410 tree tstat
= static_fn_type (tofn
);
1411 if (same_type_p (tstat
, fstat
)
1412 || fnptr_conv_p (tstat
, fstat
))
1417 if (!same_type_p (fbase
, tbase
))
1419 from
= build_memfn_type (fstat
,
1421 cp_type_quals (tbase
),
1422 type_memfn_rqual (tofn
));
1423 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1424 conv
= build_conv (ck_pmem
, from
, conv
);
1425 conv
->base_p
= true;
1427 if (fnptr_conv_p (tstat
, fstat
))
1428 conv
= build_conv (ck_fnptr
, to
, conv
);
1430 else if (tcode
== BOOLEAN_TYPE
)
1434 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1435 to member type can be converted to a prvalue of type bool. ...
1436 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1437 std::nullptr_t can be converted to a prvalue of type bool; */
1438 if (ARITHMETIC_TYPE_P (from
)
1439 || UNSCOPED_ENUM_P (from
)
1440 || fcode
== POINTER_TYPE
1441 || TYPE_PTRMEM_P (from
)
1442 || NULLPTR_TYPE_P (from
))
1444 conv
= build_conv (ck_std
, to
, conv
);
1445 if (fcode
== POINTER_TYPE
1446 || TYPE_PTRDATAMEM_P (from
)
1447 || (TYPE_PTRMEMFUNC_P (from
)
1448 && conv
->rank
< cr_pbool
)
1449 || NULLPTR_TYPE_P (from
))
1450 conv
->rank
= cr_pbool
;
1451 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1453 if (flags
& LOOKUP_NO_NARROWING
)
1454 conv
->check_narrowing
= true;
1460 /* We don't check for ENUMERAL_TYPE here because there are no standard
1461 conversions to enum type. */
1462 /* As an extension, allow conversion to complex type. */
1463 else if (ARITHMETIC_TYPE_P (to
))
1465 if (! (INTEGRAL_CODE_P (fcode
)
1466 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1467 || SCOPED_ENUM_P (from
))
1470 /* If we're parsing an enum with no fixed underlying type, we're
1471 dealing with an incomplete type, which renders the conversion
1473 if (!COMPLETE_TYPE_P (from
))
1476 conv
= build_conv (ck_std
, to
, conv
);
1478 tree underlying_type
= NULL_TREE
;
1479 if (TREE_CODE (from
) == ENUMERAL_TYPE
1480 && ENUM_FIXED_UNDERLYING_TYPE_P (from
))
1481 underlying_type
= ENUM_UNDERLYING_TYPE (from
);
1483 /* Give this a better rank if it's a promotion.
1485 To handle CWG 1601, also bump the rank if we are converting
1486 an enumeration with a fixed underlying type to the underlying
1488 if ((same_type_p (to
, type_promotes_to (from
))
1489 || (underlying_type
&& same_type_p (to
, underlying_type
)))
1490 && next_conversion (conv
)->rank
<= cr_promotion
)
1491 conv
->rank
= cr_promotion
;
1493 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1494 && vector_types_convertible_p (from
, to
, false))
1495 return build_conv (ck_std
, to
, conv
);
1496 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1497 && is_properly_derived_from (from
, to
))
1499 if (conv
->kind
== ck_rvalue
)
1500 conv
= next_conversion (conv
);
1501 conv
= build_conv (ck_base
, to
, conv
);
1502 /* The derived-to-base conversion indicates the initialization
1503 of a parameter with base type from an object of a derived
1504 type. A temporary object is created to hold the result of
1505 the conversion unless we're binding directly to a reference. */
1506 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1507 if (flags
& LOOKUP_PREFER_RVALUE
)
1508 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1509 conv
->rvaluedness_matches_p
= true;
1514 if (flags
& LOOKUP_NO_NARROWING
)
1515 conv
->check_narrowing
= true;
1520 /* Returns nonzero if T1 is reference-related to T2. */
1523 reference_related_p (tree t1
, tree t2
)
1525 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1528 t1
= TYPE_MAIN_VARIANT (t1
);
1529 t2
= TYPE_MAIN_VARIANT (t2
);
1533 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1534 to "cv2 T2" if T1 is similar to T2, or T1 is a base class of T2. */
1535 return (similar_type_p (t1
, t2
)
1536 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1537 && DERIVED_FROM_P (t1
, t2
)));
1540 /* Returns nonzero if T1 is reference-compatible with T2. */
1543 reference_compatible_p (tree t1
, tree t2
)
1547 "cv1 T1" is reference compatible with "cv2 T2" if
1548 a prvalue of type "pointer to cv2 T2" can be converted to the type
1549 "pointer to cv1 T1" via a standard conversion sequence. */
1550 tree ptype1
= build_pointer_type (t1
);
1551 tree ptype2
= build_pointer_type (t2
);
1552 conversion
*conv
= standard_conversion (ptype1
, ptype2
, NULL_TREE
,
1553 /*c_cast_p=*/false, 0, tf_none
);
1554 if (!conv
|| conv
->bad_p
)
1559 /* Return true if converting FROM to TO would involve a qualification
1563 involves_qualification_conversion_p (tree to
, tree from
)
1565 /* If we're not convering a pointer to another one, we won't get
1566 a qualification conversion. */
1567 if (!((TYPE_PTR_P (to
) && TYPE_PTR_P (from
))
1568 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
))))
1571 conversion
*conv
= standard_conversion (to
, from
, NULL_TREE
,
1572 /*c_cast_p=*/false, 0, tf_none
);
1573 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1574 if (t
->kind
== ck_qual
)
1580 /* A reference of the indicated TYPE is being bound directly to the
1581 expression represented by the implicit conversion sequence CONV.
1582 Return a conversion sequence for this binding. */
1585 direct_reference_binding (tree type
, conversion
*conv
)
1589 gcc_assert (TYPE_REF_P (type
));
1590 gcc_assert (!TYPE_REF_P (conv
->type
));
1592 t
= TREE_TYPE (type
);
1594 if (conv
->kind
== ck_identity
)
1595 /* Mark the identity conv as to not decay to rvalue. */
1596 conv
->rvaluedness_matches_p
= true;
1600 When a parameter of reference type binds directly
1601 (_dcl.init.ref_) to an argument expression, the implicit
1602 conversion sequence is the identity conversion, unless the
1603 argument expression has a type that is a derived class of the
1604 parameter type, in which case the implicit conversion sequence is
1605 a derived-to-base Conversion.
1607 If the parameter binds directly to the result of applying a
1608 conversion function to the argument expression, the implicit
1609 conversion sequence is a user-defined conversion sequence
1610 (_over.ics.user_), with the second standard conversion sequence
1611 either an identity conversion or, if the conversion function
1612 returns an entity of a type that is a derived class of the
1613 parameter type, a derived-to-base conversion. */
1614 if (is_properly_derived_from (conv
->type
, t
))
1616 /* Represent the derived-to-base conversion. */
1617 conv
= build_conv (ck_base
, t
, conv
);
1618 /* We will actually be binding to the base-class subobject in
1619 the derived class, so we mark this conversion appropriately.
1620 That way, convert_like knows not to generate a temporary. */
1621 conv
->need_temporary_p
= false;
1623 else if (involves_qualification_conversion_p (t
, conv
->type
))
1624 /* Represent the qualification conversion. After DR 2352
1625 #1 and #2 were indistinguishable conversion sequences:
1628 void f(const int* const &); // #2
1629 void g(int* p) { f(p); }
1631 because the types "int *" and "const int *const" are
1632 reference-related and we were binding both directly and they
1633 had the same rank. To break it up, we add a ck_qual under the
1634 ck_ref_bind so that conversion sequence ranking chooses #1. */
1635 conv
= build_conv (ck_qual
, t
, conv
);
1637 return build_conv (ck_ref_bind
, type
, conv
);
1640 /* Returns the conversion path from type FROM to reference type TO for
1641 purposes of reference binding. For lvalue binding, either pass a
1642 reference type to FROM or an lvalue expression to EXPR. If the
1643 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1644 the conversion returned. If C_CAST_P is true, this
1645 conversion is coming from a C-style cast. */
1648 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1649 tsubst_flags_t complain
)
1651 conversion
*conv
= NULL
;
1652 tree to
= TREE_TYPE (rto
);
1657 cp_lvalue_kind gl_kind
;
1660 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1662 expr
= instantiate_type (to
, expr
, tf_none
);
1663 if (expr
== error_mark_node
)
1665 from
= TREE_TYPE (expr
);
1668 bool copy_list_init
= false;
1669 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1671 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1672 /* DR 1288: Otherwise, if the initializer list has a single element
1673 of type E and ... [T's] referenced type is reference-related to E,
1674 the object or reference is initialized from that element...
1676 ??? With P0388R4, we should bind 't' directly to U{}:
1679 because A[] and A[2] are reference-related. But we don't do it
1680 because grok_reference_init has deduced the array size (to 1), and
1681 A[1] and A[2] aren't reference-related. */
1682 if (CONSTRUCTOR_NELTS (expr
) == 1)
1684 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1685 if (error_operand_p (elt
))
1687 tree etype
= TREE_TYPE (elt
);
1688 if (reference_related_p (to
, etype
))
1695 /* Otherwise, if T is a reference type, a prvalue temporary of the type
1696 referenced by T is copy-list-initialized, and the reference is bound
1697 to that temporary. */
1698 copy_list_init
= true;
1702 if (TYPE_REF_P (from
))
1704 from
= TREE_TYPE (from
);
1705 if (!TYPE_REF_IS_RVALUE (rfrom
)
1706 || TREE_CODE (from
) == FUNCTION_TYPE
)
1707 gl_kind
= clk_ordinary
;
1709 gl_kind
= clk_rvalueref
;
1712 gl_kind
= lvalue_kind (expr
);
1713 else if (CLASS_TYPE_P (from
)
1714 || TREE_CODE (from
) == ARRAY_TYPE
)
1715 gl_kind
= clk_class
;
1719 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1720 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1721 && (gl_kind
& clk_class
))
1724 /* Same mask as real_lvalue_p. */
1725 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1728 if ((gl_kind
& clk_bitfield
) != 0)
1729 tfrom
= unlowered_expr_type (expr
);
1731 /* Figure out whether or not the types are reference-related and
1732 reference compatible. We have to do this after stripping
1733 references from FROM. */
1734 related_p
= reference_related_p (to
, tfrom
);
1735 /* If this is a C cast, first convert to an appropriately qualified
1736 type, so that we can later do a const_cast to the desired type. */
1737 if (related_p
&& c_cast_p
1738 && !at_least_as_qualified_p (to
, tfrom
))
1739 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1740 compatible_p
= reference_compatible_p (to
, tfrom
);
1742 /* Directly bind reference when target expression's type is compatible with
1743 the reference and expression is an lvalue. In DR391, the wording in
1744 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1745 const and rvalue references to rvalues of compatible class type.
1746 We should also do direct bindings for non-class xvalues. */
1747 if ((related_p
|| compatible_p
) && gl_kind
)
1751 If the initializer expression
1753 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1754 is reference-compatible with "cv2 T2,"
1756 the reference is bound directly to the initializer expression
1760 If the initializer expression is an rvalue, with T2 a class type,
1761 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1762 is bound to the object represented by the rvalue or to a sub-object
1763 within that object. */
1765 conv
= build_identity_conv (tfrom
, expr
);
1766 conv
= direct_reference_binding (rto
, conv
);
1768 if (TYPE_REF_P (rfrom
))
1769 /* Handle rvalue reference to function properly. */
1770 conv
->rvaluedness_matches_p
1771 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1773 conv
->rvaluedness_matches_p
1774 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1776 if ((gl_kind
& clk_bitfield
) != 0
1777 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1778 /* For the purposes of overload resolution, we ignore the fact
1779 this expression is a bitfield or packed field. (In particular,
1780 [over.ics.ref] says specifically that a function with a
1781 non-const reference parameter is viable even if the
1782 argument is a bitfield.)
1784 However, when we actually call the function we must create
1785 a temporary to which to bind the reference. If the
1786 reference is volatile, or isn't const, then we cannot make
1787 a temporary, so we just issue an error when the conversion
1789 conv
->need_temporary_p
= true;
1791 /* Don't allow binding of lvalues (other than function lvalues) to
1792 rvalue references. */
1793 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1794 && TREE_CODE (to
) != FUNCTION_TYPE
)
1797 /* Nor the reverse. */
1798 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1799 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1800 || (flags
& LOOKUP_NO_RVAL_BIND
))
1801 && TREE_CODE (to
) != FUNCTION_TYPE
)
1809 /* [class.conv.fct] A conversion function is never used to convert a
1810 (possibly cv-qualified) object to the (possibly cv-qualified) same
1811 object type (or a reference to it), to a (possibly cv-qualified) base
1812 class of that type (or a reference to it).... */
1813 else if (CLASS_TYPE_P (from
) && !related_p
1814 && !(flags
& LOOKUP_NO_CONVERSION
))
1818 If the initializer expression
1820 -- has a class type (i.e., T2 is a class type) can be
1821 implicitly converted to an lvalue of type "cv3 T3," where
1822 "cv1 T1" is reference-compatible with "cv3 T3". (this
1823 conversion is selected by enumerating the applicable
1824 conversion functions (_over.match.ref_) and choosing the
1825 best one through overload resolution. (_over.match_).
1827 the reference is bound to the lvalue result of the conversion
1828 in the second case. */
1829 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1832 return cand
->second_conv
;
1835 /* From this point on, we conceptually need temporaries, even if we
1836 elide them. Only the cases above are "direct bindings". */
1837 if (flags
& LOOKUP_NO_TEMP_BIND
)
1842 When a parameter of reference type is not bound directly to an
1843 argument expression, the conversion sequence is the one required
1844 to convert the argument expression to the underlying type of the
1845 reference according to _over.best.ics_. Conceptually, this
1846 conversion sequence corresponds to copy-initializing a temporary
1847 of the underlying type with the argument expression. Any
1848 difference in top-level cv-qualification is subsumed by the
1849 initialization itself and does not constitute a conversion. */
1853 Otherwise, the reference shall be an lvalue reference to a
1854 non-volatile const type, or the reference shall be an rvalue
1857 We try below to treat this as a bad conversion to improve diagnostics,
1858 but if TO is an incomplete class, we need to reject this conversion
1859 now to avoid unnecessary instantiation. */
1860 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1861 && !COMPLETE_TYPE_P (to
))
1864 /* We're generating a temporary now, but don't bind any more in the
1865 conversion (specifically, don't slice the temporary returned by a
1866 conversion operator). */
1867 flags
|= LOOKUP_NO_TEMP_BIND
;
1869 /* Core issue 899: When [copy-]initializing a temporary to be bound
1870 to the first parameter of a copy constructor (12.8) called with
1871 a single argument in the context of direct-initialization,
1872 explicit conversion functions are also considered.
1874 So don't set LOOKUP_ONLYCONVERTING in that case. */
1875 if (!(flags
& LOOKUP_COPY_PARM
))
1876 flags
|= LOOKUP_ONLYCONVERTING
;
1879 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1884 if (conv
->user_conv_p
)
1887 /* Remember this was copy-list-initialization. */
1888 conv
->need_temporary_p
= true;
1890 /* If initializing the temporary used a conversion function,
1891 recalculate the second conversion sequence. */
1892 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1893 if (t
->kind
== ck_user
1894 && DECL_CONV_FN_P (t
->cand
->fn
))
1896 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1897 /* A prvalue of non-class type is cv-unqualified. */
1898 if (!TYPE_REF_P (ftype
) && !CLASS_TYPE_P (ftype
))
1899 ftype
= cv_unqualified (ftype
);
1900 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1901 conversion
*new_second
1902 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1906 return merge_conversion_sequences (t
, new_second
);
1910 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1911 /* This reference binding, unlike those above, requires the
1912 creation of a temporary. */
1913 conv
->need_temporary_p
= true;
1914 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1918 Otherwise, the reference shall be an lvalue reference to a
1919 non-volatile const type, or the reference shall be an rvalue
1921 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1926 Otherwise, a temporary of type "cv1 T1" is created and
1927 initialized from the initializer expression using the rules for a
1928 non-reference copy initialization. If T1 is reference-related to
1929 T2, cv1 must be the same cv-qualification as, or greater
1930 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1931 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1937 /* Returns the implicit conversion sequence (see [over.ics]) from type
1938 FROM to type TO. The optional expression EXPR may affect the
1939 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1940 true, this conversion is coming from a C-style cast. */
1943 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1944 int flags
, tsubst_flags_t complain
)
1948 if (from
== error_mark_node
|| to
== error_mark_node
1949 || expr
== error_mark_node
)
1952 /* Other flags only apply to the primary function in overload
1953 resolution, or after we've chosen one. */
1954 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1955 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1956 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1958 /* FIXME: actually we don't want warnings either, but we can't just
1959 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1960 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1961 We really ought not to issue that warning until we've committed
1962 to that conversion. */
1963 complain
&= ~tf_error
;
1965 /* Call reshape_init early to remove redundant braces. */
1966 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1967 && CLASS_TYPE_P (to
)
1968 && COMPLETE_TYPE_P (complete_type (to
))
1969 && !CLASSTYPE_NON_AGGREGATE (to
))
1971 expr
= reshape_init (to
, expr
, complain
);
1972 if (expr
== error_mark_node
)
1974 from
= TREE_TYPE (expr
);
1977 if (TYPE_REF_P (to
))
1978 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1980 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1985 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1987 if (is_std_init_list (to
) && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1988 return build_list_conv (to
, expr
, flags
, complain
);
1990 /* As an extension, allow list-initialization of _Complex. */
1991 if (TREE_CODE (to
) == COMPLEX_TYPE
1992 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
1994 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1999 /* Allow conversion from an initializer-list with one element to a
2001 if (SCALAR_TYPE_P (to
))
2003 int nelts
= CONSTRUCTOR_NELTS (expr
);
2007 elt
= build_value_init (to
, tf_none
);
2008 else if (nelts
== 1 && !CONSTRUCTOR_IS_DESIGNATED_INIT (expr
))
2009 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
2011 elt
= error_mark_node
;
2013 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
2014 c_cast_p
, flags
, complain
);
2017 conv
->check_narrowing
= true;
2018 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
2019 /* Too many levels of braces, i.e. '{{1}}'. */
2024 else if (TREE_CODE (to
) == ARRAY_TYPE
)
2025 return build_array_conv (to
, expr
, flags
, complain
);
2028 if (expr
!= NULL_TREE
2029 && (MAYBE_CLASS_TYPE_P (from
)
2030 || MAYBE_CLASS_TYPE_P (to
))
2031 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
2033 struct z_candidate
*cand
;
2035 if (CLASS_TYPE_P (to
)
2036 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
2037 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
2038 return build_aggr_conv (to
, expr
, flags
, complain
);
2040 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
2043 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
2044 && CONSTRUCTOR_NELTS (expr
) == 1
2045 && !is_list_ctor (cand
->fn
))
2047 /* "If C is not an initializer-list constructor and the
2048 initializer list has a single element of type cv U, where U is
2049 X or a class derived from X, the implicit conversion sequence
2050 has Exact Match rank if U is X, or Conversion rank if U is
2052 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
2053 tree elttype
= TREE_TYPE (elt
);
2054 if (reference_related_p (to
, elttype
))
2055 return implicit_conversion (to
, elttype
, elt
,
2056 c_cast_p
, flags
, complain
);
2058 conv
= cand
->second_conv
;
2061 /* We used to try to bind a reference to a temporary here, but that
2062 is now handled after the recursive call to this function at the end
2063 of reference_binding. */
2070 /* Like implicit_conversion, but return NULL if the conversion is bad.
2072 This is not static so that check_non_deducible_conversion can call it within
2073 add_template_candidate_real as part of overload resolution; it should not be
2074 called outside of overload resolution. */
2077 good_conversion (tree to
, tree from
, tree expr
,
2078 int flags
, tsubst_flags_t complain
)
2080 conversion
*c
= implicit_conversion (to
, from
, expr
, /*cast*/false,
2087 /* Add a new entry to the list of candidates. Used by the add_*_candidate
2088 functions. ARGS will not be changed until a single candidate is
2091 static struct z_candidate
*
2092 add_candidate (struct z_candidate
**candidates
,
2093 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
2094 size_t num_convs
, conversion
**convs
,
2095 tree access_path
, tree conversion_path
,
2096 int viable
, struct rejection_reason
*reason
,
2099 struct z_candidate
*cand
= (struct z_candidate
*)
2100 conversion_obstack_alloc (sizeof (struct z_candidate
));
2103 cand
->first_arg
= first_arg
;
2105 cand
->convs
= convs
;
2106 cand
->num_convs
= num_convs
;
2107 cand
->access_path
= access_path
;
2108 cand
->conversion_path
= conversion_path
;
2109 cand
->viable
= viable
;
2110 cand
->reason
= reason
;
2111 cand
->next
= *candidates
;
2112 cand
->flags
= flags
;
2118 /* Return the number of remaining arguments in the parameter list
2119 beginning with ARG. */
2122 remaining_arguments (tree arg
)
2126 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
2127 arg
= TREE_CHAIN (arg
))
2133 /* [over.match.copy]: When initializing a temporary object (12.2) to be bound
2134 to the first parameter of a constructor where the parameter is of type
2135 "reference to possibly cv-qualified T" and the constructor is called with a
2136 single argument in the context of direct-initialization of an object of type
2137 "cv2 T", explicit conversion functions are also considered.
2139 So set LOOKUP_COPY_PARM to let reference_binding know that
2140 it's being called in that context. */
2143 conv_flags (int i
, int nargs
, tree fn
, tree arg
, int flags
)
2147 if (i
== 0 && nargs
== 1 && DECL_CONSTRUCTOR_P (fn
)
2148 && (t
= FUNCTION_FIRST_USER_PARMTYPE (fn
))
2149 && (same_type_ignoring_top_level_qualifiers_p
2150 (non_reference (TREE_VALUE (t
)), DECL_CONTEXT (fn
))))
2152 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2153 lflags
|= LOOKUP_COPY_PARM
;
2154 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2155 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2156 lflags
|= LOOKUP_NO_CONVERSION
;
2159 lflags
|= LOOKUP_ONLYCONVERTING
;
2164 /* Create an overload candidate for the function or method FN called
2165 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
2166 FLAGS is passed on to implicit_conversion.
2168 This does not change ARGS.
2170 CTYPE, if non-NULL, is the type we want to pretend this function
2171 comes from for purposes of overload resolution. */
2173 static struct z_candidate
*
2174 add_function_candidate (struct z_candidate
**candidates
,
2175 tree fn
, tree ctype
, tree first_arg
,
2176 const vec
<tree
, va_gc
> *args
, tree access_path
,
2177 tree conversion_path
, int flags
,
2179 tsubst_flags_t complain
)
2181 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2184 tree orig_first_arg
= first_arg
;
2187 struct rejection_reason
*reason
= NULL
;
2189 /* At this point we should not see any functions which haven't been
2190 explicitly declared, except for friend functions which will have
2191 been found using argument dependent lookup. */
2192 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2194 /* The `this', `in_chrg' and VTT arguments to constructors are not
2195 considered in overload resolution. */
2196 if (DECL_CONSTRUCTOR_P (fn
))
2198 if (ctor_omit_inherited_parms (fn
))
2199 /* Bring back parameters omitted from an inherited ctor. */
2200 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2202 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2203 skip
= num_artificial_parms_for (fn
);
2204 if (skip
> 0 && first_arg
!= NULL_TREE
)
2207 first_arg
= NULL_TREE
;
2213 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2215 convs
= alloc_conversions (len
);
2217 /* 13.3.2 - Viable functions [over.match.viable]
2218 First, to be a viable function, a candidate function shall have enough
2219 parameters to agree in number with the arguments in the list.
2221 We need to check this first; otherwise, checking the ICSes might cause
2222 us to produce an ill-formed template instantiation. */
2224 parmnode
= parmlist
;
2225 for (i
= 0; i
< len
; ++i
)
2227 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2229 parmnode
= TREE_CHAIN (parmnode
);
2232 if ((i
< len
&& parmnode
)
2233 || !sufficient_parms_p (parmnode
))
2235 int remaining
= remaining_arguments (parmnode
);
2237 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2240 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2241 parameter of type "reference to cv C" (including such a constructor
2242 instantiated from a template) is excluded from the set of candidate
2243 functions when used to construct an object of type D with an argument list
2244 containing a single argument if C is reference-related to D. */
2245 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2246 && flag_new_inheriting_ctors
2247 && DECL_INHERITED_CTOR (fn
))
2249 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2250 tree dtype
= DECL_CONTEXT (fn
);
2251 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2252 if (reference_related_p (ptype
, dtype
)
2253 && reference_related_p (btype
, ptype
))
2256 reason
= inherited_ctor_rejection ();
2260 /* Second, for a function to be viable, its constraints must be
2262 if (flag_concepts
&& viable
&& !constraints_satisfied_p (fn
))
2264 reason
= constraint_failure ();
2268 /* When looking for a function from a subobject from an implicit
2269 copy/move constructor/operator=, don't consider anything that takes (a
2270 reference to) an unrelated type. See c++/44909 and core 1092. */
2271 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2273 if (DECL_CONSTRUCTOR_P (fn
))
2275 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2276 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2282 parmnode
= chain_index (i
-1, parmlist
);
2283 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2288 /* This only applies at the top level. */
2289 flags
&= ~LOOKUP_DEFAULTED
;
2295 /* Third, for F to be a viable function, there shall exist for each
2296 argument an implicit conversion sequence that converts that argument
2297 to the corresponding parameter of F. */
2299 parmnode
= parmlist
;
2301 for (i
= 0; i
< len
; ++i
)
2303 tree argtype
, to_type
;
2308 if (parmnode
== void_list_node
)
2313 /* Already set during deduction. */
2314 parmnode
= TREE_CHAIN (parmnode
);
2318 if (i
== 0 && first_arg
!= NULL_TREE
)
2321 arg
= CONST_CAST_TREE (
2322 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2323 argtype
= lvalue_type (arg
);
2325 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2326 && ! DECL_CONSTRUCTOR_P (fn
));
2330 tree parmtype
= TREE_VALUE (parmnode
);
2332 parmnode
= TREE_CHAIN (parmnode
);
2334 /* The type of the implicit object parameter ('this') for
2335 overload resolution is not always the same as for the
2336 function itself; conversion functions are considered to
2337 be members of the class being converted, and functions
2338 introduced by a using-declaration are considered to be
2339 members of the class that uses them.
2341 Since build_over_call ignores the ICS for the `this'
2342 parameter, we can just change the parm type. */
2343 if (ctype
&& is_this
)
2345 parmtype
= cp_build_qualified_type
2346 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2347 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2349 /* If the function has a ref-qualifier, the implicit
2350 object parameter has reference type. */
2351 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2352 parmtype
= cp_build_reference_type (parmtype
, rv
);
2353 /* The special handling of 'this' conversions in compare_ics
2354 does not apply if there is a ref-qualifier. */
2359 parmtype
= build_pointer_type (parmtype
);
2360 /* We don't use build_this here because we don't want to
2361 capture the object argument until we've chosen a
2362 non-static member function. */
2363 arg
= build_address (arg
);
2364 argtype
= lvalue_type (arg
);
2368 int lflags
= conv_flags (i
, len
-skip
, fn
, arg
, flags
);
2370 t
= implicit_conversion (parmtype
, argtype
, arg
,
2371 /*c_cast_p=*/false, lflags
, complain
);
2376 t
= build_identity_conv (argtype
, arg
);
2377 t
->ellipsis_p
= true;
2388 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
,
2389 EXPR_LOCATION (arg
));
2396 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
,
2397 EXPR_LOCATION (arg
));
2403 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2404 access_path
, conversion_path
, viable
, reason
, flags
);
2407 /* Create an overload candidate for the conversion function FN which will
2408 be invoked for expression OBJ, producing a pointer-to-function which
2409 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2410 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2411 passed on to implicit_conversion.
2413 Actually, we don't really care about FN; we care about the type it
2414 converts to. There may be multiple conversion functions that will
2415 convert to that type, and we rely on build_user_type_conversion_1 to
2416 choose the best one; so when we create our candidate, we record the type
2417 instead of the function. */
2419 static struct z_candidate
*
2420 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2421 const vec
<tree
, va_gc
> *arglist
,
2422 tree access_path
, tree conversion_path
,
2423 tsubst_flags_t complain
)
2425 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2426 int i
, len
, viable
, flags
;
2427 tree parmlist
, parmnode
;
2429 struct rejection_reason
*reason
;
2431 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2432 parmlist
= TREE_TYPE (parmlist
);
2433 parmlist
= TYPE_ARG_TYPES (parmlist
);
2435 len
= vec_safe_length (arglist
) + 1;
2436 convs
= alloc_conversions (len
);
2437 parmnode
= parmlist
;
2439 flags
= LOOKUP_IMPLICIT
;
2442 /* Don't bother looking up the same type twice. */
2443 if (*candidates
&& (*candidates
)->fn
== totype
)
2446 for (i
= 0; i
< len
; ++i
)
2448 tree arg
, argtype
, convert_type
= NULL_TREE
;
2454 arg
= (*arglist
)[i
- 1];
2455 argtype
= lvalue_type (arg
);
2459 t
= build_identity_conv (argtype
, NULL_TREE
);
2460 t
= build_conv (ck_user
, totype
, t
);
2461 /* Leave the 'cand' field null; we'll figure out the conversion in
2462 convert_like_real if this candidate is chosen. */
2463 convert_type
= totype
;
2465 else if (parmnode
== void_list_node
)
2469 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2470 /*c_cast_p=*/false, flags
, complain
);
2471 convert_type
= TREE_VALUE (parmnode
);
2475 t
= build_identity_conv (argtype
, arg
);
2476 t
->ellipsis_p
= true;
2477 convert_type
= argtype
;
2487 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
,
2488 EXPR_LOCATION (arg
));
2495 parmnode
= TREE_CHAIN (parmnode
);
2499 || ! sufficient_parms_p (parmnode
))
2501 int remaining
= remaining_arguments (parmnode
);
2503 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2506 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2507 access_path
, conversion_path
, viable
, reason
, flags
);
2511 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2512 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2513 int flags
, tsubst_flags_t complain
)
2520 struct rejection_reason
*reason
= NULL
;
2525 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2526 convs
= alloc_conversions (num_convs
);
2528 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2529 conversion ops are allowed. We handle that here by just checking for
2530 boolean_type_node because other operators don't ask for it. COND_EXPR
2531 also does contextual conversion to bool for the first operand, but we
2532 handle that in build_conditional_expr, and type1 here is operand 2. */
2533 if (type1
!= boolean_type_node
)
2534 flags
|= LOOKUP_ONLYCONVERTING
;
2536 for (i
= 0; i
< 2; ++i
)
2541 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2542 /*c_cast_p=*/false, flags
, complain
);
2546 /* We need something for printing the candidate. */
2547 t
= build_identity_conv (types
[i
], NULL_TREE
);
2548 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2549 types
[i
], EXPR_LOCATION (args
[i
]));
2554 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2556 EXPR_LOCATION (args
[i
]));
2561 /* For COND_EXPR we rearranged the arguments; undo that now. */
2564 convs
[2] = convs
[1];
2565 convs
[1] = convs
[0];
2566 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2567 /*c_cast_p=*/false, flags
,
2574 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2576 EXPR_LOCATION (args
[2]));
2580 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2582 /*access_path=*/NULL_TREE
,
2583 /*conversion_path=*/NULL_TREE
,
2584 viable
, reason
, flags
);
2588 is_complete (tree t
)
2590 return COMPLETE_TYPE_P (complete_type (t
));
2593 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2596 promoted_arithmetic_type_p (tree type
)
2600 In this section, the term promoted integral type is used to refer
2601 to those integral types which are preserved by integral promotion
2602 (including e.g. int and long but excluding e.g. char).
2603 Similarly, the term promoted arithmetic type refers to promoted
2604 integral types plus floating types. */
2605 return ((CP_INTEGRAL_TYPE_P (type
)
2606 && same_type_p (type_promotes_to (type
), type
))
2607 || TREE_CODE (type
) == REAL_TYPE
);
2610 /* Create any builtin operator overload candidates for the operator in
2611 question given the converted operand types TYPE1 and TYPE2. The other
2612 args are passed through from add_builtin_candidates to
2613 build_builtin_candidate.
2615 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2616 If CODE is requires candidates operands of the same type of the kind
2617 of which TYPE1 and TYPE2 are, we add both candidates
2618 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2621 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2622 enum tree_code code2
, tree fnname
, tree type1
,
2623 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2624 tsubst_flags_t complain
)
2628 case POSTINCREMENT_EXPR
:
2629 case POSTDECREMENT_EXPR
:
2630 args
[1] = integer_zero_node
;
2631 type2
= integer_type_node
;
2640 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2641 and VQ is either volatile or empty, there exist candidate operator
2642 functions of the form
2643 VQ T& operator++(VQ T&);
2644 T operator++(VQ T&, int);
2645 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2646 type other than bool, and VQ is either volatile or empty, there exist
2647 candidate operator functions of the form
2648 VQ T& operator--(VQ T&);
2649 T operator--(VQ T&, int);
2650 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2651 complete object type, and VQ is either volatile or empty, there exist
2652 candidate operator functions of the form
2653 T*VQ& operator++(T*VQ&);
2654 T*VQ& operator--(T*VQ&);
2655 T* operator++(T*VQ&, int);
2656 T* operator--(T*VQ&, int); */
2658 case POSTDECREMENT_EXPR
:
2659 case PREDECREMENT_EXPR
:
2660 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2663 case POSTINCREMENT_EXPR
:
2664 case PREINCREMENT_EXPR
:
2665 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2667 type1
= build_reference_type (type1
);
2672 /* 7 For every cv-qualified or cv-unqualified object type T, there
2673 exist candidate operator functions of the form
2677 8 For every function type T, there exist candidate operator functions of
2679 T& operator*(T*); */
2682 if (TYPE_PTR_P (type1
)
2683 && (TYPE_PTROB_P (type1
)
2684 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2688 /* 9 For every type T, there exist candidate operator functions of the form
2691 10For every promoted arithmetic type T, there exist candidate operator
2692 functions of the form
2696 case UNARY_PLUS_EXPR
: /* unary + */
2697 if (TYPE_PTR_P (type1
))
2701 if (ARITHMETIC_TYPE_P (type1
))
2705 /* 11For every promoted integral type T, there exist candidate operator
2706 functions of the form
2710 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2714 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2715 is the same type as C2 or is a derived class of C2, T is a complete
2716 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2717 there exist candidate operator functions of the form
2718 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2719 where CV12 is the union of CV1 and CV2. */
2722 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2724 tree c1
= TREE_TYPE (type1
);
2725 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2727 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2728 && (TYPE_PTRMEMFUNC_P (type2
)
2729 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2734 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2735 didate operator functions of the form
2740 bool operator<(L, R);
2741 bool operator>(L, R);
2742 bool operator<=(L, R);
2743 bool operator>=(L, R);
2744 bool operator==(L, R);
2745 bool operator!=(L, R);
2746 where LR is the result of the usual arithmetic conversions between
2749 14For every pair of types T and I, where T is a cv-qualified or cv-
2750 unqualified complete object type and I is a promoted integral type,
2751 there exist candidate operator functions of the form
2752 T* operator+(T*, I);
2753 T& operator[](T*, I);
2754 T* operator-(T*, I);
2755 T* operator+(I, T*);
2756 T& operator[](I, T*);
2758 15For every T, where T is a pointer to complete object type, there exist
2759 candidate operator functions of the form112)
2760 ptrdiff_t operator-(T, T);
2762 16For every pointer or enumeration type T, there exist candidate operator
2763 functions of the form
2764 bool operator<(T, T);
2765 bool operator>(T, T);
2766 bool operator<=(T, T);
2767 bool operator>=(T, T);
2768 bool operator==(T, T);
2769 bool operator!=(T, T);
2771 17For every pointer to member type T, there exist candidate operator
2772 functions of the form
2773 bool operator==(T, T);
2774 bool operator!=(T, T); */
2777 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2779 if (TYPE_PTROB_P (type1
)
2780 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2782 type2
= ptrdiff_type_node
;
2787 case TRUNC_DIV_EXPR
:
2788 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2794 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2795 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2797 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2802 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2814 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2816 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2818 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2819 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2821 if (TYPE_PTR_P (type1
)
2822 && null_ptr_cst_p (args
[1]))
2827 if (null_ptr_cst_p (args
[0])
2828 && TYPE_PTR_P (type2
))
2836 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2840 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2842 type1
= ptrdiff_type_node
;
2845 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2847 type2
= ptrdiff_type_node
;
2852 /* 18For every pair of promoted integral types L and R, there exist candi-
2853 date operator functions of the form
2860 where LR is the result of the usual arithmetic conversions between
2863 case TRUNC_MOD_EXPR
:
2869 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2873 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2874 type, VQ is either volatile or empty, and R is a promoted arithmetic
2875 type, there exist candidate operator functions of the form
2876 VQ L& operator=(VQ L&, R);
2877 VQ L& operator*=(VQ L&, R);
2878 VQ L& operator/=(VQ L&, R);
2879 VQ L& operator+=(VQ L&, R);
2880 VQ L& operator-=(VQ L&, R);
2882 20For every pair T, VQ), where T is any type and VQ is either volatile
2883 or empty, there exist candidate operator functions of the form
2884 T*VQ& operator=(T*VQ&, T*);
2886 21For every pair T, VQ), where T is a pointer to member type and VQ is
2887 either volatile or empty, there exist candidate operator functions of
2889 VQ T& operator=(VQ T&, T);
2891 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2892 unqualified complete object type, VQ is either volatile or empty, and
2893 I is a promoted integral type, there exist candidate operator func-
2895 T*VQ& operator+=(T*VQ&, I);
2896 T*VQ& operator-=(T*VQ&, I);
2898 23For every triple L, VQ, R), where L is an integral or enumeration
2899 type, VQ is either volatile or empty, and R is a promoted integral
2900 type, there exist candidate operator functions of the form
2902 VQ L& operator%=(VQ L&, R);
2903 VQ L& operator<<=(VQ L&, R);
2904 VQ L& operator>>=(VQ L&, R);
2905 VQ L& operator&=(VQ L&, R);
2906 VQ L& operator^=(VQ L&, R);
2907 VQ L& operator|=(VQ L&, R); */
2914 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2916 type2
= ptrdiff_type_node
;
2921 case TRUNC_DIV_EXPR
:
2922 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2926 case TRUNC_MOD_EXPR
:
2932 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2937 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2939 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2940 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2941 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2942 || ((TYPE_PTRMEMFUNC_P (type1
)
2943 || TYPE_PTR_P (type1
))
2944 && null_ptr_cst_p (args
[1])))
2954 type1
= build_reference_type (type1
);
2960 For every pair of promoted arithmetic types L and R, there
2961 exist candidate operator functions of the form
2963 LR operator?(bool, L, R);
2965 where LR is the result of the usual arithmetic conversions
2966 between types L and R.
2968 For every type T, where T is a pointer or pointer-to-member
2969 type, there exist candidate operator functions of the form T
2970 operator?(bool, T, T); */
2972 if (promoted_arithmetic_type_p (type1
)
2973 && promoted_arithmetic_type_p (type2
))
2977 /* Otherwise, the types should be pointers. */
2978 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2981 /* We don't check that the two types are the same; the logic
2982 below will actually create two candidates; one in which both
2983 parameter types are TYPE1, and one in which both parameter
2989 if (ARITHMETIC_TYPE_P (type1
))
2997 /* Make sure we don't create builtin candidates with dependent types. */
2998 bool u1
= uses_template_parms (type1
);
2999 bool u2
= type2
? uses_template_parms (type2
) : false;
3002 /* Try to recover if one of the types is non-dependent. But if
3003 there's only one type, there's nothing we can do. */
3006 /* And we lose if both are dependent. */
3009 /* Or if they have different forms. */
3010 if (TREE_CODE (type1
) != TREE_CODE (type2
))
3019 /* If we're dealing with two pointer types or two enumeral types,
3020 we need candidates for both of them. */
3021 if (type2
&& !same_type_p (type1
, type2
)
3022 && TREE_CODE (type1
) == TREE_CODE (type2
)
3023 && (TYPE_REF_P (type1
)
3024 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
3025 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
3026 || TYPE_PTRMEMFUNC_P (type1
)
3027 || MAYBE_CLASS_TYPE_P (type1
)
3028 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
3030 if (TYPE_PTR_OR_PTRMEM_P (type1
))
3032 tree cptype
= composite_pointer_type (type1
, type2
,
3037 if (cptype
!= error_mark_node
)
3039 build_builtin_candidate
3040 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
3046 build_builtin_candidate
3047 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
3048 build_builtin_candidate
3049 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
3053 build_builtin_candidate
3054 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
3058 type_decays_to (tree type
)
3060 if (TREE_CODE (type
) == ARRAY_TYPE
)
3061 return build_pointer_type (TREE_TYPE (type
));
3062 if (TREE_CODE (type
) == FUNCTION_TYPE
)
3063 return build_pointer_type (type
);
3067 /* There are three conditions of builtin candidates:
3069 1) bool-taking candidates. These are the same regardless of the input.
3070 2) pointer-pair taking candidates. These are generated for each type
3071 one of the input types converts to.
3072 3) arithmetic candidates. According to the standard, we should generate
3073 all of these, but I'm trying not to...
3075 Here we generate a superset of the possible candidates for this particular
3076 case. That is a subset of the full set the standard defines, plus some
3077 other cases which the standard disallows. add_builtin_candidate will
3078 filter out the invalid set. */
3081 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
3082 enum tree_code code2
, tree fnname
, tree
*args
,
3083 int flags
, tsubst_flags_t complain
)
3087 tree type
, argtypes
[3], t
;
3088 /* TYPES[i] is the set of possible builtin-operator parameter types
3089 we will consider for the Ith argument. */
3090 vec
<tree
, va_gc
> *types
[2];
3093 for (i
= 0; i
< 3; ++i
)
3096 argtypes
[i
] = unlowered_expr_type (args
[i
]);
3098 argtypes
[i
] = NULL_TREE
;
3103 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
3104 and VQ is either volatile or empty, there exist candidate operator
3105 functions of the form
3106 VQ T& operator++(VQ T&); */
3108 case POSTINCREMENT_EXPR
:
3109 case PREINCREMENT_EXPR
:
3110 case POSTDECREMENT_EXPR
:
3111 case PREDECREMENT_EXPR
:
3116 /* 24There also exist candidate operator functions of the form
3117 bool operator!(bool);
3118 bool operator&&(bool, bool);
3119 bool operator||(bool, bool); */
3121 case TRUTH_NOT_EXPR
:
3122 build_builtin_candidate
3123 (candidates
, fnname
, boolean_type_node
,
3124 NULL_TREE
, args
, argtypes
, flags
, complain
);
3127 case TRUTH_ORIF_EXPR
:
3128 case TRUTH_ANDIF_EXPR
:
3129 build_builtin_candidate
3130 (candidates
, fnname
, boolean_type_node
,
3131 boolean_type_node
, args
, argtypes
, flags
, complain
);
3153 types
[0] = make_tree_vector ();
3154 types
[1] = make_tree_vector ();
3156 for (i
= 0; i
< 2; ++i
)
3160 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
3164 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
3167 convs
= lookup_conversions (argtypes
[i
]);
3169 if (code
== COND_EXPR
)
3171 if (lvalue_p (args
[i
]))
3172 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3174 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3180 for (; convs
; convs
= TREE_CHAIN (convs
))
3182 type
= TREE_TYPE (convs
);
3185 && (!TYPE_REF_P (type
)
3186 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3189 if (code
== COND_EXPR
&& TYPE_REF_P (type
))
3190 vec_safe_push (types
[i
], type
);
3192 type
= non_reference (type
);
3193 if (i
!= 0 || ! ref1
)
3195 type
= cv_unqualified (type_decays_to (type
));
3196 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3197 vec_safe_push (types
[i
], type
);
3198 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3199 type
= type_promotes_to (type
);
3202 if (! vec_member (type
, types
[i
]))
3203 vec_safe_push (types
[i
], type
);
3208 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3209 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3210 type
= non_reference (argtypes
[i
]);
3211 if (i
!= 0 || ! ref1
)
3213 type
= cv_unqualified (type_decays_to (type
));
3214 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3215 vec_safe_push (types
[i
], type
);
3216 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3217 type
= type_promotes_to (type
);
3219 vec_safe_push (types
[i
], type
);
3223 /* Run through the possible parameter types of both arguments,
3224 creating candidates with those parameter types. */
3225 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3230 if (!types
[1]->is_empty ())
3231 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3232 add_builtin_candidate
3233 (candidates
, code
, code2
, fnname
, t
,
3234 u
, args
, argtypes
, flags
, complain
);
3236 add_builtin_candidate
3237 (candidates
, code
, code2
, fnname
, t
,
3238 NULL_TREE
, args
, argtypes
, flags
, complain
);
3241 release_tree_vector (types
[0]);
3242 release_tree_vector (types
[1]);
3246 /* If TMPL can be successfully instantiated as indicated by
3247 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3249 TMPL is the template. EXPLICIT_TARGS are any explicit template
3250 arguments. ARGLIST is the arguments provided at the call-site.
3251 This does not change ARGLIST. The RETURN_TYPE is the desired type
3252 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3253 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3254 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3256 static struct z_candidate
*
3257 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3258 tree ctype
, tree explicit_targs
, tree first_arg
,
3259 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3260 tree access_path
, tree conversion_path
,
3261 int flags
, tree obj
, unification_kind_t strict
,
3262 tsubst_flags_t complain
)
3264 int ntparms
= DECL_NTPARMS (tmpl
);
3265 tree targs
= make_tree_vec (ntparms
);
3266 unsigned int len
= vec_safe_length (arglist
);
3267 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3268 unsigned int skip_without_in_chrg
= 0;
3269 tree first_arg_without_in_chrg
= first_arg
;
3270 tree
*args_without_in_chrg
;
3271 unsigned int nargs_without_in_chrg
;
3272 unsigned int ia
, ix
;
3274 struct z_candidate
*cand
;
3276 struct rejection_reason
*reason
= NULL
;
3278 conversion
**convs
= NULL
;
3280 /* We don't do deduction on the in-charge parameter, the VTT
3281 parameter or 'this'. */
3282 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3284 if (first_arg_without_in_chrg
!= NULL_TREE
)
3285 first_arg_without_in_chrg
= NULL_TREE
;
3286 else if (return_type
&& strict
== DEDUCE_CALL
)
3287 /* We're deducing for a call to the result of a template conversion
3288 function, so the args don't contain 'this'; leave them alone. */;
3290 ++skip_without_in_chrg
;
3293 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3294 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3295 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3297 if (first_arg_without_in_chrg
!= NULL_TREE
)
3298 first_arg_without_in_chrg
= NULL_TREE
;
3300 ++skip_without_in_chrg
;
3303 if (len
< skip_without_in_chrg
)
3306 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3307 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3308 TREE_TYPE ((*arglist
)[0])))
3310 /* 12.8/6 says, "A declaration of a constructor for a class X is
3311 ill-formed if its first parameter is of type (optionally cv-qualified)
3312 X and either there are no other parameters or else all other
3313 parameters have default arguments. A member function template is never
3314 instantiated to produce such a constructor signature."
3316 So if we're trying to copy an object of the containing class, don't
3317 consider a template constructor that has a first parameter type that
3318 is just a template parameter, as we would deduce a signature that we
3319 would then reject in the code below. */
3320 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3322 firstparm
= TREE_VALUE (firstparm
);
3323 if (PACK_EXPANSION_P (firstparm
))
3324 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3325 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3327 gcc_assert (!explicit_targs
);
3328 reason
= invalid_copy_with_fn_template_rejection ();
3334 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3335 + (len
- skip_without_in_chrg
));
3336 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3338 if (first_arg_without_in_chrg
!= NULL_TREE
)
3340 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3343 for (ix
= skip_without_in_chrg
;
3344 vec_safe_iterate (arglist
, ix
, &arg
);
3347 args_without_in_chrg
[ia
] = arg
;
3350 gcc_assert (ia
== nargs_without_in_chrg
);
3352 errs
= errorcount
+sorrycount
;
3354 convs
= alloc_conversions (nargs
);
3355 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3356 args_without_in_chrg
,
3357 nargs_without_in_chrg
,
3358 return_type
, strict
, flags
, convs
,
3359 false, complain
& tf_decltype
);
3361 if (fn
== error_mark_node
)
3363 /* Don't repeat unification later if it already resulted in errors. */
3364 if (errorcount
+sorrycount
== errs
)
3365 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3366 targs
, args_without_in_chrg
,
3367 nargs_without_in_chrg
,
3368 return_type
, strict
, flags
);
3370 reason
= template_unification_error_rejection ();
3374 /* Now the explicit specifier might have been deduced; check if this
3375 declaration is explicit. If it is and we're ignoring non-converting
3376 constructors, don't add this function to the set of candidates. */
3377 if ((flags
& LOOKUP_ONLYCONVERTING
) && DECL_NONCONVERTING_P (fn
))
3380 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3382 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3383 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3386 /* We're trying to produce a constructor with a prohibited signature,
3387 as discussed above; handle here any cases we didn't catch then,
3389 reason
= invalid_copy_with_fn_template_rejection ();
3394 if (obj
!= NULL_TREE
)
3395 /* Aha, this is a conversion function. */
3396 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3397 access_path
, conversion_path
, complain
);
3399 cand
= add_function_candidate (candidates
, fn
, ctype
,
3400 first_arg
, arglist
, access_path
,
3401 conversion_path
, flags
, convs
, complain
);
3402 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3403 /* This situation can occur if a member template of a template
3404 class is specialized. Then, instantiate_template might return
3405 an instantiation of the specialization, in which case the
3406 DECL_TI_TEMPLATE field will point at the original
3407 specialization. For example:
3409 template <class T> struct S { template <class U> void f(U);
3410 template <> void f(int) {}; };
3414 Here, TMPL will be template <class U> S<double>::f(U).
3415 And, instantiate template will give us the specialization
3416 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3417 for this will point at template <class T> template <> S<T>::f(int),
3418 so that we can find the definition. For the purposes of
3419 overload resolution, however, we want the original TMPL. */
3420 cand
->template_decl
= build_template_info (tmpl
, targs
);
3422 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3423 cand
->explicit_targs
= explicit_targs
;
3427 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3428 access_path
, conversion_path
, 0, reason
, flags
);
3432 static struct z_candidate
*
3433 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3434 tree explicit_targs
, tree first_arg
,
3435 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3436 tree access_path
, tree conversion_path
, int flags
,
3437 unification_kind_t strict
, tsubst_flags_t complain
)
3440 add_template_candidate_real (candidates
, tmpl
, ctype
,
3441 explicit_targs
, first_arg
, arglist
,
3442 return_type
, access_path
, conversion_path
,
3443 flags
, NULL_TREE
, strict
, complain
);
3446 /* Create an overload candidate for the conversion function template TMPL,
3447 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3448 pointer-to-function which will in turn be called with the argument list
3449 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3450 passed on to implicit_conversion. */
3452 static struct z_candidate
*
3453 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3455 const vec
<tree
, va_gc
> *arglist
,
3456 tree return_type
, tree access_path
,
3457 tree conversion_path
, tsubst_flags_t complain
)
3459 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3460 core issue 2189, let's disable this candidate if there are any call
3466 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3467 NULL_TREE
, arglist
, return_type
, access_path
,
3468 conversion_path
, 0, obj
, DEDUCE_CALL
,
3472 /* The CANDS are the set of candidates that were considered for
3473 overload resolution. Return the set of viable candidates, or CANDS
3474 if none are viable. If any of the candidates were viable, set
3475 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3476 considered viable only if it is strictly viable. */
3478 static struct z_candidate
*
3479 splice_viable (struct z_candidate
*cands
,
3483 struct z_candidate
*viable
;
3484 struct z_candidate
**last_viable
;
3485 struct z_candidate
**cand
;
3486 bool found_strictly_viable
= false;
3488 /* Be strict inside templates, since build_over_call won't actually
3489 do the conversions to get pedwarns. */
3490 if (processing_template_decl
)
3494 last_viable
= &viable
;
3495 *any_viable_p
= false;
3500 struct z_candidate
*c
= *cand
;
3502 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3504 /* Be strict in the presence of a viable candidate. Also if
3505 there are template candidates, so that we get deduction errors
3506 for them instead of silently preferring a bad conversion. */
3508 if (viable
&& !found_strictly_viable
)
3510 /* Put any spliced near matches back onto the main list so
3511 that we see them if there is no strict match. */
3512 *any_viable_p
= false;
3513 *last_viable
= cands
;
3516 last_viable
= &viable
;
3520 if (strict_p
? c
->viable
== 1 : c
->viable
)
3525 last_viable
= &c
->next
;
3526 *any_viable_p
= true;
3528 found_strictly_viable
= true;
3534 return viable
? viable
: cands
;
3538 any_strictly_viable (struct z_candidate
*cands
)
3540 for (; cands
; cands
= cands
->next
)
3541 if (cands
->viable
== 1)
3546 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3547 words, it is about to become the "this" pointer for a member
3548 function call. Take the address of the object. */
3551 build_this (tree obj
)
3553 /* In a template, we are only concerned about the type of the
3554 expression, so we can take a shortcut. */
3555 if (processing_template_decl
)
3556 return build_address (obj
);
3558 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3561 /* Returns true iff functions are equivalent. Equivalent functions are
3562 not '==' only if one is a function-local extern function or if
3563 both are extern "C". */
3566 equal_functions (tree fn1
, tree fn2
)
3568 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3570 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3572 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3573 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3574 return decls_match (fn1
, fn2
);
3578 /* Print information about a candidate FN being rejected due to INFO. */
3581 print_conversion_rejection (location_t loc
, struct conversion_info
*info
,
3584 tree from
= info
->from
;
3586 from
= lvalue_type (from
);
3587 if (info
->n_arg
== -1)
3589 /* Conversion of implicit `this' argument failed. */
3590 if (!TYPE_P (info
->from
))
3591 /* A bad conversion for 'this' must be discarding cv-quals. */
3592 inform (loc
, " passing %qT as %<this%> "
3593 "argument discards qualifiers",
3596 inform (loc
, " no known conversion for implicit "
3597 "%<this%> parameter from %qH to %qI",
3598 from
, info
->to_type
);
3600 else if (!TYPE_P (info
->from
))
3602 if (info
->n_arg
>= 0)
3603 inform (loc
, " conversion of argument %d would be ill-formed:",
3605 perform_implicit_conversion (info
->to_type
, info
->from
,
3606 tf_warning_or_error
);
3608 else if (info
->n_arg
== -2)
3609 /* Conversion of conversion function return value failed. */
3610 inform (loc
, " no known conversion from %qH to %qI",
3611 from
, info
->to_type
);
3614 if (TREE_CODE (fn
) == FUNCTION_DECL
)
3615 loc
= get_fndecl_argument_location (fn
, info
->n_arg
);
3616 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3617 info
->n_arg
+ 1, from
, info
->to_type
);
3621 /* Print information about a candidate with WANT parameters and we found
3625 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3627 inform_n (loc
, want
,
3628 " candidate expects %d argument, %d provided",
3629 " candidate expects %d arguments, %d provided",
3633 /* Print information about one overload candidate CANDIDATE. MSGSTR
3634 is the text to print before the candidate itself.
3636 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3637 to have been run through gettext by the caller. This wart makes
3638 life simpler in print_z_candidates and for the translators. */
3641 print_z_candidate (location_t loc
, const char *msgstr
,
3642 struct z_candidate
*candidate
)
3644 const char *msg
= (msgstr
== NULL
3646 : ACONCAT ((_(msgstr
), " ", NULL
)));
3647 tree fn
= candidate
->fn
;
3648 if (flag_new_inheriting_ctors
)
3649 fn
= strip_inheriting_ctors (fn
);
3650 location_t cloc
= location_of (fn
);
3652 if (identifier_p (fn
))
3655 if (candidate
->num_convs
== 3)
3656 inform (cloc
, "%s%<%D(%T, %T, %T)%> (built-in)", msg
, fn
,
3657 candidate
->convs
[0]->type
,
3658 candidate
->convs
[1]->type
,
3659 candidate
->convs
[2]->type
);
3660 else if (candidate
->num_convs
== 2)
3661 inform (cloc
, "%s%<%D(%T, %T)%> (built-in)", msg
, fn
,
3662 candidate
->convs
[0]->type
,
3663 candidate
->convs
[1]->type
);
3665 inform (cloc
, "%s%<%D(%T)%> (built-in)", msg
, fn
,
3666 candidate
->convs
[0]->type
);
3668 else if (TYPE_P (fn
))
3669 inform (cloc
, "%s%qT (conversion)", msg
, fn
);
3670 else if (candidate
->viable
== -1)
3671 inform (cloc
, "%s%#qD (near match)", msg
, fn
);
3672 else if (DECL_DELETED_FN (fn
))
3673 inform (cloc
, "%s%#qD (deleted)", msg
, fn
);
3675 inform (cloc
, "%s%#qD", msg
, fn
);
3676 if (fn
!= candidate
->fn
)
3678 cloc
= location_of (candidate
->fn
);
3679 inform (cloc
, " inherited here");
3681 /* Give the user some information about why this candidate failed. */
3682 if (candidate
->reason
!= NULL
)
3684 struct rejection_reason
*r
= candidate
->reason
;
3689 print_arity_information (cloc
, r
->u
.arity
.actual
,
3690 r
->u
.arity
.expected
);
3692 case rr_arg_conversion
:
3693 print_conversion_rejection (cloc
, &r
->u
.conversion
, fn
);
3695 case rr_bad_arg_conversion
:
3696 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
, fn
);
3698 case rr_explicit_conversion
:
3699 inform (cloc
, " return type %qT of explicit conversion function "
3700 "cannot be converted to %qT with a qualification "
3701 "conversion", r
->u
.conversion
.from
,
3702 r
->u
.conversion
.to_type
);
3704 case rr_template_conversion
:
3705 inform (cloc
, " conversion from return type %qT of template "
3706 "conversion function specialization to %qT is not an "
3707 "exact match", r
->u
.conversion
.from
,
3708 r
->u
.conversion
.to_type
);
3710 case rr_template_unification
:
3711 /* We use template_unification_error_rejection if unification caused
3712 actual non-SFINAE errors, in which case we don't need to repeat
3714 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3716 inform (cloc
, " substitution of deduced template arguments "
3717 "resulted in errors seen above");
3720 /* Re-run template unification with diagnostics. */
3721 inform (cloc
, " template argument deduction/substitution failed:");
3722 fn_type_unification (r
->u
.template_unification
.tmpl
,
3723 r
->u
.template_unification
.explicit_targs
,
3725 (r
->u
.template_unification
.num_targs
)),
3726 r
->u
.template_unification
.args
,
3727 r
->u
.template_unification
.nargs
,
3728 r
->u
.template_unification
.return_type
,
3729 r
->u
.template_unification
.strict
,
3730 r
->u
.template_unification
.flags
,
3733 case rr_invalid_copy
:
3735 " a constructor taking a single argument of its own "
3736 "class type is invalid");
3738 case rr_constraint_failure
:
3739 diagnose_constraints (cloc
, fn
, NULL_TREE
);
3741 case rr_inherited_ctor
:
3742 inform (cloc
, " an inherited constructor is not a candidate for "
3743 "initialization from an expression of the same or derived "
3748 /* This candidate didn't have any issues or we failed to
3749 handle a particular code. Either way... */
3756 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3758 struct z_candidate
*cand1
;
3759 struct z_candidate
**cand2
;
3764 /* Remove non-viable deleted candidates. */
3766 for (cand2
= &cand1
; *cand2
; )
3768 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3769 && !(*cand2
)->viable
3770 && DECL_DELETED_FN ((*cand2
)->fn
))
3771 *cand2
= (*cand2
)->next
;
3773 cand2
= &(*cand2
)->next
;
3775 /* ...if there are any non-deleted ones. */
3779 /* There may be duplicates in the set of candidates. We put off
3780 checking this condition as long as possible, since we have no way
3781 to eliminate duplicates from a set of functions in less than n^2
3782 time. Now we are about to emit an error message, so it is more
3783 permissible to go slowly. */
3784 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3786 tree fn
= cand1
->fn
;
3787 /* Skip builtin candidates and conversion functions. */
3790 cand2
= &cand1
->next
;
3793 if (DECL_P ((*cand2
)->fn
)
3794 && equal_functions (fn
, (*cand2
)->fn
))
3795 *cand2
= (*cand2
)->next
;
3797 cand2
= &(*cand2
)->next
;
3801 for (; candidates
; candidates
= candidates
->next
)
3802 print_z_candidate (loc
, N_("candidate:"), candidates
);
3805 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3806 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3807 the result of the conversion function to convert it to the final
3808 desired type. Merge the two sequences into a single sequence,
3809 and return the merged sequence. */
3812 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3815 bool bad
= user_seq
->bad_p
;
3817 gcc_assert (user_seq
->kind
== ck_user
);
3819 /* Find the end of the second conversion sequence. */
3820 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3822 /* The entire sequence is a user-conversion sequence. */
3823 (*t
)->user_conv_p
= true;
3828 if ((*t
)->rvaluedness_matches_p
)
3829 /* We're binding a reference directly to the result of the conversion.
3830 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3831 type, but we want it back. */
3832 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3834 /* Replace the identity conversion with the user conversion
3841 /* Handle overload resolution for initializing an object of class type from
3842 an initializer list. First we look for a suitable constructor that
3843 takes a std::initializer_list; if we don't find one, we then look for a
3844 non-list constructor.
3846 Parameters are as for add_candidates, except that the arguments are in
3847 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3848 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3851 add_list_candidates (tree fns
, tree first_arg
,
3852 const vec
<tree
, va_gc
> *args
, tree totype
,
3853 tree explicit_targs
, bool template_only
,
3854 tree conversion_path
, tree access_path
,
3856 struct z_candidate
**candidates
,
3857 tsubst_flags_t complain
)
3859 gcc_assert (*candidates
== NULL
);
3861 /* We're looking for a ctor for list-initialization. */
3862 flags
|= LOOKUP_LIST_INIT_CTOR
;
3863 /* And we don't allow narrowing conversions. We also use this flag to
3864 avoid the copy constructor call for copy-list-initialization. */
3865 flags
|= LOOKUP_NO_NARROWING
;
3867 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3868 tree init_list
= (*args
)[nart
];
3870 /* Always use the default constructor if the list is empty (DR 990). */
3871 if (CONSTRUCTOR_NELTS (init_list
) == 0
3872 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3874 /* If the class has a list ctor, try passing the list as a single
3875 argument first, but only consider list ctors. */
3876 else if (TYPE_HAS_LIST_CTOR (totype
))
3878 flags
|= LOOKUP_LIST_ONLY
;
3879 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3880 explicit_targs
, template_only
, conversion_path
,
3881 access_path
, flags
, candidates
, complain
);
3882 if (any_strictly_viable (*candidates
))
3886 /* Expand the CONSTRUCTOR into a new argument vec. */
3887 vec
<tree
, va_gc
> *new_args
;
3888 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3889 for (unsigned i
= 0; i
< nart
; ++i
)
3890 new_args
->quick_push ((*args
)[i
]);
3891 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3892 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3894 /* We aren't looking for list-ctors anymore. */
3895 flags
&= ~LOOKUP_LIST_ONLY
;
3896 /* We allow more user-defined conversions within an init-list. */
3897 flags
&= ~LOOKUP_NO_CONVERSION
;
3899 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3900 explicit_targs
, template_only
, conversion_path
,
3901 access_path
, flags
, candidates
, complain
);
3904 /* Returns the best overload candidate to perform the requested
3905 conversion. This function is used for three the overloading situations
3906 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3907 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3908 per [dcl.init.ref], so we ignore temporary bindings. */
3910 static struct z_candidate
*
3911 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3912 tsubst_flags_t complain
)
3914 struct z_candidate
*candidates
, *cand
;
3916 tree ctors
= NULL_TREE
;
3917 tree conv_fns
= NULL_TREE
;
3918 conversion
*conv
= NULL
;
3919 tree first_arg
= NULL_TREE
;
3920 vec
<tree
, va_gc
> *args
= NULL
;
3927 fromtype
= TREE_TYPE (expr
);
3929 /* We represent conversion within a hierarchy using RVALUE_CONV and
3930 BASE_CONV, as specified by [over.best.ics]; these become plain
3931 constructor calls, as specified in [dcl.init]. */
3932 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3933 || !DERIVED_FROM_P (totype
, fromtype
));
3935 if (CLASS_TYPE_P (totype
))
3936 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3937 creating a garbage BASELINK; constructors can't be inherited. */
3938 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3940 if (MAYBE_CLASS_TYPE_P (fromtype
))
3942 tree to_nonref
= non_reference (totype
);
3943 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3944 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3945 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3947 /* [class.conv.fct] A conversion function is never used to
3948 convert a (possibly cv-qualified) object to the (possibly
3949 cv-qualified) same object type (or a reference to it), to a
3950 (possibly cv-qualified) base class of that type (or a
3951 reference to it)... */
3954 conv_fns
= lookup_conversions (fromtype
);
3958 flags
|= LOOKUP_NO_CONVERSION
;
3959 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3960 flags
|= LOOKUP_NO_NARROWING
;
3962 /* It's OK to bind a temporary for converting constructor arguments, but
3963 not in converting the return value of a conversion operator. */
3964 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3965 | (flags
& LOOKUP_NO_NARROWING
));
3966 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3970 int ctorflags
= flags
;
3972 first_arg
= build_dummy_object (totype
);
3974 /* We should never try to call the abstract or base constructor
3976 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3977 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3979 args
= make_tree_vector_single (expr
);
3980 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3982 /* List-initialization. */
3983 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3984 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3985 ctorflags
, &candidates
, complain
);
3989 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3990 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3991 ctorflags
, &candidates
, complain
);
3994 for (cand
= candidates
; cand
; cand
= cand
->next
)
3996 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3998 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3999 set, then this is copy-initialization. In that case, "The
4000 result of the call is then used to direct-initialize the
4001 object that is the destination of the copy-initialization."
4004 We represent this in the conversion sequence with an
4005 rvalue conversion, which means a constructor call. */
4006 if (!TYPE_REF_P (totype
)
4007 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
4009 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
4015 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
4016 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
4021 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
4023 tree conversion_path
= TREE_PURPOSE (conv_fns
);
4024 struct z_candidate
*old_candidates
;
4026 /* If we are called to convert to a reference type, we are trying to
4027 find a direct binding, so don't even consider temporaries. If
4028 we don't find a direct binding, the caller will try again to
4029 look for a temporary binding. */
4030 if (TYPE_REF_P (totype
))
4031 convflags
|= LOOKUP_NO_TEMP_BIND
;
4033 old_candidates
= candidates
;
4034 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
4036 conversion_path
, TYPE_BINFO (fromtype
),
4037 flags
, &candidates
, complain
);
4039 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
4041 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
4043 = implicit_conversion (totype
,
4046 /*c_cast_p=*/false, convflags
,
4049 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
4050 copy-initialization. In that case, "The result of the
4051 call is then used to direct-initialize the object that is
4052 the destination of the copy-initialization." [dcl.init]
4054 We represent this in the conversion sequence with an
4055 rvalue conversion, which means a constructor call. But
4056 don't add a second rvalue conversion if there's already
4057 one there. Which there really shouldn't be, but it's
4058 harmless since we'd add it here anyway. */
4059 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
4060 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
4061 ics
= build_conv (ck_rvalue
, totype
, ics
);
4063 cand
->second_conv
= ics
;
4068 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
4070 EXPR_LOCATION (expr
));
4072 else if (TYPE_REF_P (totype
) && !ics
->rvaluedness_matches_p
4073 && TREE_CODE (TREE_TYPE (totype
)) != FUNCTION_TYPE
)
4075 /* If we are called to convert to a reference type, we are trying
4076 to find a direct binding per [over.match.ref], so rvaluedness
4077 must match for non-functions. */
4080 else if (DECL_NONCONVERTING_P (cand
->fn
)
4081 && ics
->rank
> cr_exact
)
4083 /* 13.3.1.5: For direct-initialization, those explicit
4084 conversion functions that are not hidden within S and
4085 yield type T or a type that can be converted to type T
4086 with a qualification conversion (4.4) are also candidate
4088 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
4089 I've raised this issue with the committee. --jason 9/2011 */
4091 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
4093 else if (cand
->viable
== 1 && ics
->bad_p
)
4097 = bad_arg_conversion_rejection (NULL_TREE
, -2,
4099 EXPR_LOCATION (expr
));
4101 else if (primary_template_specialization_p (cand
->fn
)
4102 && ics
->rank
> cr_exact
)
4104 /* 13.3.3.1.2: If the user-defined conversion is specified by
4105 a specialization of a conversion function template, the
4106 second standard conversion sequence shall have exact match
4109 cand
->reason
= template_conversion_rejection (rettype
, totype
);
4114 candidates
= splice_viable (candidates
, false, &any_viable_p
);
4118 release_tree_vector (args
);
4122 cand
= tourney (candidates
, complain
);
4125 if (complain
& tf_error
)
4127 auto_diagnostic_group d
;
4128 error ("conversion from %qH to %qI is ambiguous",
4130 print_z_candidates (location_of (expr
), candidates
);
4133 cand
= candidates
; /* any one will do */
4134 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
4135 cand
->second_conv
->user_conv_p
= true;
4136 if (!any_strictly_viable (candidates
))
4137 cand
->second_conv
->bad_p
= true;
4138 if (flags
& LOOKUP_ONLYCONVERTING
)
4139 cand
->second_conv
->need_temporary_p
= true;
4140 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
4141 ambiguous conversion is no worse than another user-defined
4148 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
4149 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
4150 else if (cand
->second_conv
->kind
== ck_rvalue
)
4151 /* DR 5: [in the first step of copy-initialization]...if the function
4152 is a constructor, the call initializes a temporary of the
4153 cv-unqualified version of the destination type. */
4154 convtype
= cv_unqualified (totype
);
4157 /* Build the user conversion sequence. */
4161 build_identity_conv (TREE_TYPE (expr
), expr
));
4163 if (cand
->viable
== -1)
4166 /* We're performing the maybe-rvalue overload resolution and
4167 a conversion function is in play. Reject converting the return
4168 value of the conversion function to a base class. */
4169 if ((flags
& LOOKUP_PREFER_RVALUE
) && !DECL_CONSTRUCTOR_P (cand
->fn
))
4170 for (conversion
*t
= cand
->second_conv
; t
; t
= next_conversion (t
))
4171 if (t
->kind
== ck_base
)
4174 /* Remember that this was a list-initialization. */
4175 if (flags
& LOOKUP_NO_NARROWING
)
4176 conv
->check_narrowing
= true;
4178 /* Combine it with the second conversion sequence. */
4179 cand
->second_conv
= merge_conversion_sequences (conv
,
4185 /* Wrapper for above. */
4188 build_user_type_conversion (tree totype
, tree expr
, int flags
,
4189 tsubst_flags_t complain
)
4191 struct z_candidate
*cand
;
4194 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4195 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
4199 if (cand
->second_conv
->kind
== ck_ambig
)
4200 ret
= error_mark_node
;
4203 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4204 ret
= convert_from_reference (expr
);
4210 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4214 /* Worker for build_converted_constant_expr. */
4217 build_converted_constant_expr_internal (tree type
, tree expr
,
4218 int flags
, tsubst_flags_t complain
)
4223 location_t loc
= cp_expr_loc_or_input_loc (expr
);
4225 if (error_operand_p (expr
))
4226 return error_mark_node
;
4228 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4229 p
= conversion_obstack_alloc (0);
4231 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4232 /*c_cast_p=*/false, flags
, complain
);
4234 /* A converted constant expression of type T is an expression, implicitly
4235 converted to type T, where the converted expression is a constant
4236 expression and the implicit conversion sequence contains only
4238 * user-defined conversions,
4239 * lvalue-to-rvalue conversions (7.1),
4240 * array-to-pointer conversions (7.2),
4241 * function-to-pointer conversions (7.3),
4242 * qualification conversions (7.5),
4243 * integral promotions (7.6),
4244 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4245 * null pointer conversions (7.11) from std::nullptr_t,
4246 * null member pointer conversions (7.12) from std::nullptr_t, and
4247 * function pointer conversions (7.13),
4249 and where the reference binding (if any) binds directly. */
4251 for (conversion
*c
= conv
;
4252 conv
&& c
->kind
!= ck_identity
;
4253 c
= next_conversion (c
))
4257 /* A conversion function is OK. If it isn't constexpr, we'll
4258 complain later that the argument isn't constant. */
4260 /* The lvalue-to-rvalue conversion is OK. */
4262 /* Array-to-pointer and function-to-pointer. */
4264 /* Function pointer conversions. */
4266 /* Qualification conversions. */
4271 if (c
->need_temporary_p
)
4273 if (complain
& tf_error
)
4274 error_at (loc
, "initializing %qH with %qI in converted "
4275 "constant expression does not bind directly",
4276 type
, next_conversion (c
)->type
);
4285 t
= next_conversion (c
)->type
;
4286 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4287 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4288 /* Integral promotion or conversion. */
4290 if (NULLPTR_TYPE_P (t
))
4291 /* Conversion from nullptr to pointer or pointer-to-member. */
4294 if (complain
& tf_error
)
4295 error_at (loc
, "conversion from %qH to %qI in a "
4296 "converted constant expression", t
, type
);
4305 /* Avoid confusing convert_nontype_argument by introducing
4306 a redundant conversion to the same reference type. */
4307 if (conv
&& conv
->kind
== ck_ref_bind
4308 && REFERENCE_REF_P (expr
))
4310 tree ref
= TREE_OPERAND (expr
, 0);
4311 if (same_type_p (type
, TREE_TYPE (ref
)))
4317 /* Don't copy a class in a template. */
4318 if (CLASS_TYPE_P (type
) && conv
->kind
== ck_rvalue
4319 && processing_template_decl
)
4320 conv
= next_conversion (conv
);
4322 conv
->check_narrowing
= true;
4323 conv
->check_narrowing_const_only
= true;
4324 expr
= convert_like (conv
, expr
, complain
);
4328 if (complain
& tf_error
)
4329 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4330 TREE_TYPE (expr
), type
);
4331 expr
= error_mark_node
;
4334 /* Free all the conversions we allocated. */
4335 obstack_free (&conversion_obstack
, p
);
4340 /* Subroutine of convert_nontype_argument.
4342 EXPR is an expression used in a context that requires a converted
4343 constant-expression, such as a template non-type parameter. Do any
4344 necessary conversions (that are permitted for converted
4345 constant-expressions) to convert it to the desired type.
4347 This function doesn't consider explicit conversion functions. If
4348 you mean to use "a contextually converted constant expression of type
4349 bool", use build_converted_constant_bool_expr.
4351 If conversion is successful, returns the converted expression;
4352 otherwise, returns error_mark_node. */
4355 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4357 return build_converted_constant_expr_internal (type
, expr
, LOOKUP_IMPLICIT
,
4361 /* Used to create "a contextually converted constant expression of type
4362 bool". This differs from build_converted_constant_expr in that it
4363 also considers explicit conversion functions. */
4366 build_converted_constant_bool_expr (tree expr
, tsubst_flags_t complain
)
4368 return build_converted_constant_expr_internal (boolean_type_node
, expr
,
4369 LOOKUP_NORMAL
, complain
);
4372 /* Do any initial processing on the arguments to a function call. */
4374 static vec
<tree
, va_gc
> *
4375 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4380 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4382 if (error_operand_p (arg
))
4384 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4386 if (complain
& tf_error
)
4387 error_at (cp_expr_loc_or_input_loc (arg
),
4388 "invalid use of void expression");
4391 else if (invalid_nonstatic_memfn_p (EXPR_LOCATION (arg
), arg
, complain
))
4397 /* Perform overload resolution on FN, which is called with the ARGS.
4399 Return the candidate function selected by overload resolution, or
4400 NULL if the event that overload resolution failed. In the case
4401 that overload resolution fails, *CANDIDATES will be the set of
4402 candidates considered, and ANY_VIABLE_P will be set to true or
4403 false to indicate whether or not any of the candidates were
4406 The ARGS should already have gone through RESOLVE_ARGS before this
4407 function is called. */
4409 static struct z_candidate
*
4410 perform_overload_resolution (tree fn
,
4411 const vec
<tree
, va_gc
> *args
,
4412 struct z_candidate
**candidates
,
4413 bool *any_viable_p
, tsubst_flags_t complain
)
4415 struct z_candidate
*cand
;
4416 tree explicit_targs
;
4419 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4421 explicit_targs
= NULL_TREE
;
4425 *any_viable_p
= true;
4428 gcc_assert (OVL_P (fn
) || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4430 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4432 explicit_targs
= TREE_OPERAND (fn
, 1);
4433 fn
= TREE_OPERAND (fn
, 0);
4437 /* Add the various candidate functions. */
4438 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4439 explicit_targs
, template_only
,
4440 /*conversion_path=*/NULL_TREE
,
4441 /*access_path=*/NULL_TREE
,
4443 candidates
, complain
);
4445 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4447 cand
= tourney (*candidates
, complain
);
4451 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4455 /* Print an error message about being unable to build a call to FN with
4456 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4457 be located; CANDIDATES is a possibly empty list of such
4461 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4462 struct z_candidate
*candidates
)
4464 tree targs
= NULL_TREE
;
4465 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4467 targs
= TREE_OPERAND (fn
, 1);
4468 fn
= TREE_OPERAND (fn
, 0);
4470 tree name
= OVL_NAME (fn
);
4471 location_t loc
= location_of (name
);
4473 name
= lookup_template_function (name
, targs
);
4475 auto_diagnostic_group d
;
4476 if (!any_strictly_viable (candidates
))
4477 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4478 name
, build_tree_list_vec (args
));
4480 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4481 name
, build_tree_list_vec (args
));
4483 print_z_candidates (loc
, candidates
);
4486 /* Return an expression for a call to FN (a namespace-scope function,
4487 or a static member function) with the ARGS. This may change
4491 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4492 tsubst_flags_t complain
)
4494 struct z_candidate
*candidates
, *cand
;
4499 if (args
!= NULL
&& *args
!= NULL
)
4501 *args
= resolve_args (*args
, complain
);
4503 return error_mark_node
;
4507 tm_malloc_replacement (fn
);
4509 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4510 p
= conversion_obstack_alloc (0);
4512 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4517 if (complain
& tf_error
)
4519 // If there is a single (non-viable) function candidate,
4520 // let the error be diagnosed by cp_build_function_call_vec.
4521 if (!any_viable_p
&& candidates
&& ! candidates
->next
4522 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4523 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4525 // Otherwise, emit notes for non-viable candidates.
4526 print_error_for_call_failure (fn
, *args
, candidates
);
4528 result
= error_mark_node
;
4532 int flags
= LOOKUP_NORMAL
;
4533 /* If fn is template_id_expr, the call has explicit template arguments
4534 (e.g. func<int>(5)), communicate this info to build_over_call
4535 through flags so that later we can use it to decide whether to warn
4536 about peculiar null pointer conversion. */
4537 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4538 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4540 result
= build_over_call (cand
, flags
, complain
);
4543 /* Free all the conversions we allocated. */
4544 obstack_free (&conversion_obstack
, p
);
4549 /* Build a call to a global operator new. FNNAME is the name of the
4550 operator (either "operator new" or "operator new[]") and ARGS are
4551 the arguments provided. This may change ARGS. *SIZE points to the
4552 total number of bytes required by the allocation, and is updated if
4553 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4554 be used. If this function determines that no cookie should be
4555 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4556 is not NULL_TREE, it is evaluated before calculating the final
4557 array size, and if it fails, the array size is replaced with
4558 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4559 is non-NULL, it will be set, upon return, to the allocation
4563 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4564 tree
*size
, tree
*cookie_size
,
4565 tree align_arg
, tree size_check
,
4566 tree
*fn
, tsubst_flags_t complain
)
4568 tree original_size
= *size
;
4570 struct z_candidate
*candidates
;
4571 struct z_candidate
*cand
= NULL
;
4576 /* Set to (size_t)-1 if the size check fails. */
4577 if (size_check
!= NULL_TREE
)
4579 tree errval
= TYPE_MAX_VALUE (sizetype
);
4580 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4581 errval
= throw_bad_array_new_length ();
4582 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4583 original_size
, errval
);
4585 vec_safe_insert (*args
, 0, *size
);
4586 *args
= resolve_args (*args
, complain
);
4588 return error_mark_node
;
4594 If this lookup fails to find the name, or if the allocated type
4595 is not a class type, the allocation function's name is looked
4596 up in the global scope.
4598 we disregard block-scope declarations of "operator new". */
4599 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4600 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4604 vec
<tree
, va_gc
>* align_args
4605 = vec_copy_and_insert (*args
, align_arg
, 1);
4606 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4607 &any_viable_p
, tf_none
);
4610 /* If no aligned allocation function matches, try again without the
4614 /* Figure out what function is being called. */
4616 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4619 /* If no suitable function could be found, issue an error message
4623 if (complain
& tf_error
)
4624 print_error_for_call_failure (fns
, *args
, candidates
);
4625 return error_mark_node
;
4628 /* If a cookie is required, add some extra space. Whether
4629 or not a cookie is required cannot be determined until
4630 after we know which function was called. */
4633 bool use_cookie
= true;
4636 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4637 /* Skip the size_t parameter. */
4638 arg_types
= TREE_CHAIN (arg_types
);
4639 /* Check the remaining parameters (if any). */
4641 && TREE_CHAIN (arg_types
) == void_list_node
4642 && same_type_p (TREE_VALUE (arg_types
),
4645 /* If we need a cookie, adjust the number of bytes allocated. */
4648 /* Update the total size. */
4649 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4652 /* Set to (size_t)-1 if the size check fails. */
4653 gcc_assert (size_check
!= NULL_TREE
);
4654 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4655 *size
, TYPE_MAX_VALUE (sizetype
));
4657 /* Update the argument list to reflect the adjusted size. */
4658 (**args
)[0] = *size
;
4661 *cookie_size
= NULL_TREE
;
4664 /* Tell our caller which function we decided to call. */
4668 /* Build the CALL_EXPR. */
4669 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4672 /* Build a new call to operator(). This may change ARGS. */
4675 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4677 struct z_candidate
*candidates
= 0, *cand
;
4678 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4680 tree result
= NULL_TREE
;
4683 obj
= mark_lvalue_use (obj
);
4685 if (error_operand_p (obj
))
4686 return error_mark_node
;
4688 tree type
= TREE_TYPE (obj
);
4690 obj
= prep_operand (obj
);
4692 if (TYPE_PTRMEMFUNC_P (type
))
4694 if (complain
& tf_error
)
4695 /* It's no good looking for an overloaded operator() on a
4696 pointer-to-member-function. */
4697 error ("pointer-to-member function %qE cannot be called without "
4698 "an object; consider using %<.*%> or %<->*%>", obj
);
4699 return error_mark_node
;
4702 if (TYPE_BINFO (type
))
4704 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4705 if (fns
== error_mark_node
)
4706 return error_mark_node
;
4711 if (args
!= NULL
&& *args
!= NULL
)
4713 *args
= resolve_args (*args
, complain
);
4715 return error_mark_node
;
4718 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4719 p
= conversion_obstack_alloc (0);
4723 first_mem_arg
= obj
;
4725 add_candidates (BASELINK_FUNCTIONS (fns
),
4726 first_mem_arg
, *args
, NULL_TREE
,
4728 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4729 LOOKUP_NORMAL
, &candidates
, complain
);
4732 convs
= lookup_conversions (type
);
4734 for (; convs
; convs
= TREE_CHAIN (convs
))
4736 tree totype
= TREE_TYPE (convs
);
4738 if (TYPE_PTRFN_P (totype
)
4739 || TYPE_REFFN_P (totype
)
4740 || (TYPE_REF_P (totype
)
4741 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4742 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4746 if (DECL_NONCONVERTING_P (fn
))
4749 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4750 add_template_conv_candidate
4751 (&candidates
, fn
, obj
, *args
, totype
,
4752 /*access_path=*/NULL_TREE
,
4753 /*conversion_path=*/NULL_TREE
, complain
);
4755 add_conv_candidate (&candidates
, fn
, obj
,
4756 *args
, /*conversion_path=*/NULL_TREE
,
4757 /*access_path=*/NULL_TREE
, complain
);
4761 /* Be strict here because if we choose a bad conversion candidate, the
4762 errors we get won't mention the call context. */
4763 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4766 if (complain
& tf_error
)
4768 auto_diagnostic_group d
;
4769 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4770 build_tree_list_vec (*args
));
4771 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4773 result
= error_mark_node
;
4777 cand
= tourney (candidates
, complain
);
4780 if (complain
& tf_error
)
4782 auto_diagnostic_group d
;
4783 error ("call of %<(%T) (%A)%> is ambiguous",
4784 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4785 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4787 result
= error_mark_node
;
4789 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4790 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4791 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4792 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4795 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4796 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4800 gcc_checking_assert (TYPE_P (cand
->fn
));
4801 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4803 obj
= convert_from_reference (obj
);
4804 result
= cp_build_function_call_vec (obj
, args
, complain
);
4808 /* Free all the conversions we allocated. */
4809 obstack_free (&conversion_obstack
, p
);
4814 /* Wrapper for above. */
4817 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4820 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4821 ret
= build_op_call_1 (obj
, args
, complain
);
4822 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4826 /* Called by op_error to prepare format strings suitable for the error
4827 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4828 and a suffix (controlled by NTYPES). */
4831 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4835 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4836 : G_("no match for "), errmsg
, NULL
);
4839 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4840 else if (ntypes
== 2)
4841 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4843 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4849 op_error (const op_location_t
&loc
,
4850 enum tree_code code
, enum tree_code code2
,
4851 tree arg1
, tree arg2
, tree arg3
, bool match
)
4853 bool assop
= code
== MODIFY_EXPR
;
4854 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4859 if (flag_diagnostics_show_caret
)
4860 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4862 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4864 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4865 "in %<%E ? %E : %E%>"), 3, match
),
4867 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4870 case POSTINCREMENT_EXPR
:
4871 case POSTDECREMENT_EXPR
:
4872 if (flag_diagnostics_show_caret
)
4873 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4874 opname
, TREE_TYPE (arg1
));
4876 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4878 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4882 if (flag_diagnostics_show_caret
)
4883 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4884 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4886 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4888 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4893 if (flag_diagnostics_show_caret
)
4894 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4895 opname
, TREE_TYPE (arg1
));
4897 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4898 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4903 if (flag_diagnostics_show_caret
)
4905 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4907 op_error_string (G_("%<operator%s%>"), 2, match
),
4908 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4911 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4913 opname
, arg1
, opname
, arg2
,
4914 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4916 if (flag_diagnostics_show_caret
)
4917 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4918 opname
, TREE_TYPE (arg1
));
4920 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4922 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4927 /* Return the implicit conversion sequence that could be used to
4928 convert E1 to E2 in [expr.cond]. */
4931 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4933 tree t1
= non_reference (TREE_TYPE (e1
));
4934 tree t2
= non_reference (TREE_TYPE (e2
));
4940 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4941 implicitly converted (clause _conv_) to the type "lvalue reference to
4942 T2", subject to the constraint that in the conversion the
4943 reference must bind directly (_dcl.init.ref_) to an lvalue.
4945 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4946 implicitly converted to the type "rvalue reference to T2", subject to
4947 the constraint that the reference must bind directly. */
4950 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4951 conv
= implicit_conversion (rtype
,
4955 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4956 |LOOKUP_ONLYCONVERTING
,
4958 if (conv
&& !conv
->bad_p
)
4962 /* If E2 is a prvalue or if neither of the conversions above can be done
4963 and at least one of the operands has (possibly cv-qualified) class
4965 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4970 If E1 and E2 have class type, and the underlying class types are
4971 the same or one is a base class of the other: E1 can be converted
4972 to match E2 if the class of T2 is the same type as, or a base
4973 class of, the class of T1, and the cv-qualification of T2 is the
4974 same cv-qualification as, or a greater cv-qualification than, the
4975 cv-qualification of T1. If the conversion is applied, E1 is
4976 changed to an rvalue of type T2 that still refers to the original
4977 source class object (or the appropriate subobject thereof). */
4978 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4979 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4981 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4983 conv
= build_identity_conv (t1
, e1
);
4984 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4985 TYPE_MAIN_VARIANT (t2
)))
4986 conv
= build_conv (ck_base
, t2
, conv
);
4988 conv
= build_conv (ck_rvalue
, t2
, conv
);
4997 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4998 converted to the type that expression E2 would have if E2 were
4999 converted to an rvalue (or the type it has, if E2 is an rvalue). */
5000 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
5001 LOOKUP_IMPLICIT
, complain
);
5004 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
5005 arguments to the conditional expression. */
5008 build_conditional_expr_1 (const op_location_t
&loc
,
5009 tree arg1
, tree arg2
, tree arg3
,
5010 tsubst_flags_t complain
)
5014 tree result
= NULL_TREE
;
5015 tree result_type
= NULL_TREE
;
5016 bool is_glvalue
= true;
5017 struct z_candidate
*candidates
= 0;
5018 struct z_candidate
*cand
;
5020 tree orig_arg2
, orig_arg3
;
5022 /* As a G++ extension, the second argument to the conditional can be
5023 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
5024 c'.) If the second operand is omitted, make sure it is
5025 calculated only once. */
5028 if (complain
& tf_error
)
5029 pedwarn (loc
, OPT_Wpedantic
,
5030 "ISO C++ forbids omitting the middle term of "
5031 "a %<?:%> expression");
5033 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
5034 warn_for_omitted_condop (loc
, arg1
);
5036 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
5037 if (lvalue_p (arg1
))
5038 arg2
= arg1
= cp_stabilize_reference (arg1
);
5040 arg2
= arg1
= cp_save_expr (arg1
);
5043 /* If something has already gone wrong, just pass that fact up the
5045 if (error_operand_p (arg1
)
5046 || error_operand_p (arg2
)
5047 || error_operand_p (arg3
))
5048 return error_mark_node
;
5053 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
5055 tree arg1_type
= TREE_TYPE (arg1
);
5057 /* If arg1 is another cond_expr choosing between -1 and 0,
5058 then we can use its comparison. It may help to avoid
5059 additional comparison, produce more accurate diagnostics
5060 and enables folding. */
5061 if (TREE_CODE (arg1
) == VEC_COND_EXPR
5062 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
5063 && integer_zerop (TREE_OPERAND (arg1
, 2)))
5064 arg1
= TREE_OPERAND (arg1
, 0);
5066 arg1
= force_rvalue (arg1
, complain
);
5067 arg2
= force_rvalue (arg2
, complain
);
5068 arg3
= force_rvalue (arg3
, complain
);
5070 /* force_rvalue can return error_mark on valid arguments. */
5071 if (error_operand_p (arg1
)
5072 || error_operand_p (arg2
)
5073 || error_operand_p (arg3
))
5074 return error_mark_node
;
5076 arg2_type
= TREE_TYPE (arg2
);
5077 arg3_type
= TREE_TYPE (arg3
);
5079 if (!VECTOR_TYPE_P (arg2_type
)
5080 && !VECTOR_TYPE_P (arg3_type
))
5082 /* Rely on the error messages of the scalar version. */
5083 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
5084 orig_arg2
, orig_arg3
, complain
);
5085 if (scal
== error_mark_node
)
5086 return error_mark_node
;
5087 tree stype
= TREE_TYPE (scal
);
5088 tree ctype
= TREE_TYPE (arg1_type
);
5089 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
5090 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
5092 if (complain
& tf_error
)
5093 error_at (loc
, "inferred scalar type %qT is not an integer or "
5094 "floating-point type of the same size as %qT", stype
,
5095 COMPARISON_CLASS_P (arg1
)
5096 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
5098 return error_mark_node
;
5101 tree vtype
= build_opaque_vector_type (stype
,
5102 TYPE_VECTOR_SUBPARTS (arg1_type
));
5103 /* We could pass complain & tf_warning to unsafe_conversion_p,
5104 but the warnings (like Wsign-conversion) have already been
5105 given by the scalar build_conditional_expr_1. We still check
5106 unsafe_conversion_p to forbid truncating long long -> float. */
5107 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
5109 if (complain
& tf_error
)
5110 error_at (loc
, "conversion of scalar %qH to vector %qI "
5111 "involves truncation", arg2_type
, vtype
);
5112 return error_mark_node
;
5114 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
5116 if (complain
& tf_error
)
5117 error_at (loc
, "conversion of scalar %qH to vector %qI "
5118 "involves truncation", arg3_type
, vtype
);
5119 return error_mark_node
;
5122 arg2
= cp_convert (stype
, arg2
, complain
);
5123 arg2
= save_expr (arg2
);
5124 arg2
= build_vector_from_val (vtype
, arg2
);
5126 arg3
= cp_convert (stype
, arg3
, complain
);
5127 arg3
= save_expr (arg3
);
5128 arg3
= build_vector_from_val (vtype
, arg3
);
5132 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5134 enum stv_conv convert_flag
=
5135 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5136 complain
& tf_error
);
5138 switch (convert_flag
)
5141 return error_mark_node
;
5144 arg2
= save_expr (arg2
);
5145 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5146 arg2
= build_vector_from_val (arg3_type
, arg2
);
5147 arg2_type
= TREE_TYPE (arg2
);
5152 arg3
= save_expr (arg3
);
5153 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5154 arg3
= build_vector_from_val (arg2_type
, arg3
);
5155 arg3_type
= TREE_TYPE (arg3
);
5163 if (!same_type_p (arg2_type
, arg3_type
)
5164 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5165 TYPE_VECTOR_SUBPARTS (arg2_type
))
5166 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5168 if (complain
& tf_error
)
5170 "incompatible vector types in conditional expression: "
5171 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5172 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5173 return error_mark_node
;
5176 if (!COMPARISON_CLASS_P (arg1
))
5178 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5179 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5181 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5186 The first expression is implicitly converted to bool (clause
5188 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5190 if (error_operand_p (arg1
))
5191 return error_mark_node
;
5195 If either the second or the third operand has type (possibly
5196 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5197 array-to-pointer (_conv.array_), and function-to-pointer
5198 (_conv.func_) standard conversions are performed on the second
5199 and third operands. */
5200 arg2_type
= unlowered_expr_type (arg2
);
5201 arg3_type
= unlowered_expr_type (arg3
);
5202 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5204 /* 'void' won't help in resolving an overloaded expression on the
5205 other side, so require it to resolve by itself. */
5206 if (arg2_type
== unknown_type_node
)
5208 arg2
= resolve_nondeduced_context_or_error (arg2
, complain
);
5209 arg2_type
= TREE_TYPE (arg2
);
5211 if (arg3_type
== unknown_type_node
)
5213 arg3
= resolve_nondeduced_context_or_error (arg3
, complain
);
5214 arg3_type
= TREE_TYPE (arg3
);
5219 One of the following shall hold:
5221 --The second or the third operand (but not both) is a
5222 throw-expression (_except.throw_); the result is of the type
5223 and value category of the other.
5225 --Both the second and the third operands have type void; the
5226 result is of type void and is a prvalue. */
5227 if (TREE_CODE (arg2
) == THROW_EXPR
5228 && TREE_CODE (arg3
) != THROW_EXPR
)
5230 result_type
= arg3_type
;
5231 is_glvalue
= glvalue_p (arg3
);
5233 else if (TREE_CODE (arg2
) != THROW_EXPR
5234 && TREE_CODE (arg3
) == THROW_EXPR
)
5236 result_type
= arg2_type
;
5237 is_glvalue
= glvalue_p (arg2
);
5239 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5241 result_type
= void_type_node
;
5246 if (complain
& tf_error
)
5248 if (VOID_TYPE_P (arg2_type
))
5249 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5250 "second operand to the conditional operator "
5251 "is of type %<void%>, but the third operand is "
5252 "neither a throw-expression nor of type %<void%>");
5254 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5255 "third operand to the conditional operator "
5256 "is of type %<void%>, but the second operand is "
5257 "neither a throw-expression nor of type %<void%>");
5259 return error_mark_node
;
5262 goto valid_operands
;
5266 Otherwise, if the second and third operand have different types,
5267 and either has (possibly cv-qualified) class type, or if both are
5268 glvalues of the same value category and the same type except for
5269 cv-qualification, an attempt is made to convert each of those operands
5270 to the type of the other. */
5271 else if (!same_type_p (arg2_type
, arg3_type
)
5272 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5273 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5275 && glvalue_p (arg2
) && glvalue_p (arg3
)
5276 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5280 bool converted
= false;
5282 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5283 p
= conversion_obstack_alloc (0);
5285 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5286 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5290 If both can be converted, or one can be converted but the
5291 conversion is ambiguous, the program is ill-formed. If
5292 neither can be converted, the operands are left unchanged and
5293 further checking is performed as described below. If exactly
5294 one conversion is possible, that conversion is applied to the
5295 chosen operand and the converted operand is used in place of
5296 the original operand for the remainder of this section. */
5297 if ((conv2
&& !conv2
->bad_p
5298 && conv3
&& !conv3
->bad_p
)
5299 || (conv2
&& conv2
->kind
== ck_ambig
)
5300 || (conv3
&& conv3
->kind
== ck_ambig
))
5302 if (complain
& tf_error
)
5304 error_at (loc
, "operands to %<?:%> have different types "
5306 arg2_type
, arg3_type
);
5307 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5308 inform (loc
, " and each type can be converted to the other");
5309 else if (conv2
&& conv2
->kind
== ck_ambig
)
5310 convert_like (conv2
, arg2
, complain
);
5312 convert_like (conv3
, arg3
, complain
);
5314 result
= error_mark_node
;
5316 else if (conv2
&& !conv2
->bad_p
)
5318 arg2
= convert_like (conv2
, arg2
, complain
);
5319 arg2
= convert_from_reference (arg2
);
5320 arg2_type
= TREE_TYPE (arg2
);
5321 /* Even if CONV2 is a valid conversion, the result of the
5322 conversion may be invalid. For example, if ARG3 has type
5323 "volatile X", and X does not have a copy constructor
5324 accepting a "volatile X&", then even if ARG2 can be
5325 converted to X, the conversion will fail. */
5326 if (error_operand_p (arg2
))
5327 result
= error_mark_node
;
5330 else if (conv3
&& !conv3
->bad_p
)
5332 arg3
= convert_like (conv3
, arg3
, complain
);
5333 arg3
= convert_from_reference (arg3
);
5334 arg3_type
= TREE_TYPE (arg3
);
5335 if (error_operand_p (arg3
))
5336 result
= error_mark_node
;
5340 /* Free all the conversions we allocated. */
5341 obstack_free (&conversion_obstack
, p
);
5346 /* If, after the conversion, both operands have class type,
5347 treat the cv-qualification of both operands as if it were the
5348 union of the cv-qualification of the operands.
5350 The standard is not clear about what to do in this
5351 circumstance. For example, if the first operand has type
5352 "const X" and the second operand has a user-defined
5353 conversion to "volatile X", what is the type of the second
5354 operand after this step? Making it be "const X" (matching
5355 the first operand) seems wrong, as that discards the
5356 qualification without actually performing a copy. Leaving it
5357 as "volatile X" seems wrong as that will result in the
5358 conditional expression failing altogether, even though,
5359 according to this step, the one operand could be converted to
5360 the type of the other. */
5362 && CLASS_TYPE_P (arg2_type
)
5363 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5364 arg2_type
= arg3_type
=
5365 cp_build_qualified_type (arg2_type
,
5366 cp_type_quals (arg2_type
)
5367 | cp_type_quals (arg3_type
));
5372 If the second and third operands are glvalues of the same value
5373 category and have the same type, the result is of that type and
5375 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5376 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5377 && same_type_p (arg2_type
, arg3_type
))
5379 result_type
= arg2_type
;
5380 arg2
= mark_lvalue_use (arg2
);
5381 arg3
= mark_lvalue_use (arg3
);
5382 goto valid_operands
;
5387 Otherwise, the result is an rvalue. If the second and third
5388 operand do not have the same type, and either has (possibly
5389 cv-qualified) class type, overload resolution is used to
5390 determine the conversions (if any) to be applied to the operands
5391 (_over.match.oper_, _over.built_). */
5393 if (!same_type_p (arg2_type
, arg3_type
)
5394 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5400 /* Rearrange the arguments so that add_builtin_candidate only has
5401 to know about two args. In build_builtin_candidate, the
5402 arguments are unscrambled. */
5406 add_builtin_candidates (&candidates
,
5409 ovl_op_identifier (false, COND_EXPR
),
5411 LOOKUP_NORMAL
, complain
);
5415 If the overload resolution fails, the program is
5417 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5420 if (complain
& tf_error
)
5421 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5422 arg2_type
, arg3_type
);
5423 return error_mark_node
;
5425 cand
= tourney (candidates
, complain
);
5428 if (complain
& tf_error
)
5430 auto_diagnostic_group d
;
5431 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5432 print_z_candidates (loc
, candidates
);
5434 return error_mark_node
;
5439 Otherwise, the conversions thus determined are applied, and
5440 the converted operands are used in place of the original
5441 operands for the remainder of this section. */
5442 conv
= cand
->convs
[0];
5443 arg1
= convert_like (conv
, arg1
, complain
);
5444 conv
= cand
->convs
[1];
5445 arg2
= convert_like (conv
, arg2
, complain
);
5446 arg2_type
= TREE_TYPE (arg2
);
5447 conv
= cand
->convs
[2];
5448 arg3
= convert_like (conv
, arg3
, complain
);
5449 arg3_type
= TREE_TYPE (arg3
);
5454 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5455 and function-to-pointer (_conv.func_) standard conversions are
5456 performed on the second and third operands.
5458 We need to force the lvalue-to-rvalue conversion here for class types,
5459 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5460 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5463 arg2
= force_rvalue (arg2
, complain
);
5464 if (!CLASS_TYPE_P (arg2_type
))
5465 arg2_type
= TREE_TYPE (arg2
);
5467 arg3
= force_rvalue (arg3
, complain
);
5468 if (!CLASS_TYPE_P (arg3_type
))
5469 arg3_type
= TREE_TYPE (arg3
);
5471 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5472 return error_mark_node
;
5476 After those conversions, one of the following shall hold:
5478 --The second and third operands have the same type; the result is of
5480 if (same_type_p (arg2_type
, arg3_type
))
5481 result_type
= arg2_type
;
5484 --The second and third operands have arithmetic or enumeration
5485 type; the usual arithmetic conversions are performed to bring
5486 them to a common type, and the result is of that type. */
5487 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5488 || UNSCOPED_ENUM_P (arg2_type
))
5489 && (ARITHMETIC_TYPE_P (arg3_type
)
5490 || UNSCOPED_ENUM_P (arg3_type
)))
5492 /* In this case, there is always a common type. */
5493 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5495 if (complain
& tf_warning
)
5496 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5497 "implicit conversion from %qH to %qI to "
5498 "match other result of conditional",
5501 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5502 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5504 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5505 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5506 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5507 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5508 && (DECL_CONTEXT (stripped_orig_arg2
)
5509 == DECL_CONTEXT (stripped_orig_arg3
)))
5510 /* Two enumerators from the same enumeration can have different
5511 types when the enumeration is still being defined. */;
5512 else if (complain
& tf_warning
)
5513 warning_at (loc
, OPT_Wenum_compare
, "enumerated mismatch "
5514 "in conditional expression: %qT vs %qT",
5515 arg2_type
, arg3_type
);
5517 else if (extra_warnings
5518 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5519 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5520 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5521 && !same_type_p (arg2_type
,
5522 type_promotes_to (arg3_type
)))))
5524 if (complain
& tf_warning
)
5525 warning_at (loc
, OPT_Wextra
, "enumerated and non-enumerated "
5526 "type in conditional expression");
5529 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5530 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5534 --The second and third operands have pointer type, or one has
5535 pointer type and the other is a null pointer constant; pointer
5536 conversions (_conv.ptr_) and qualification conversions
5537 (_conv.qual_) are performed to bring them to their composite
5538 pointer type (_expr.rel_). The result is of the composite
5541 --The second and third operands have pointer to member type, or
5542 one has pointer to member type and the other is a null pointer
5543 constant; pointer to member conversions (_conv.mem_) and
5544 qualification conversions (_conv.qual_) are performed to bring
5545 them to a common type, whose cv-qualification shall match the
5546 cv-qualification of either the second or the third operand.
5547 The result is of the common type. */
5548 else if ((null_ptr_cst_p (arg2
)
5549 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5550 || (null_ptr_cst_p (arg3
)
5551 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5552 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5553 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5554 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5556 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5557 arg3
, CPO_CONDITIONAL_EXPR
,
5559 if (result_type
== error_mark_node
)
5560 return error_mark_node
;
5561 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5562 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5567 if (complain
& tf_error
)
5568 error_at (loc
, "operands to %<?:%> have different types %qT and %qT",
5569 arg2_type
, arg3_type
);
5570 return error_mark_node
;
5573 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5574 return error_mark_node
;
5577 if (processing_template_decl
&& is_glvalue
)
5579 /* Let lvalue_kind know this was a glvalue. */
5580 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5581 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5584 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5586 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5587 warn here, because the COND_EXPR will be turned into ARG2. */
5588 if (warn_duplicated_branches
5589 && (complain
& tf_warning
)
5590 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5591 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5592 "this condition has identical branches");
5594 /* We can't use result_type below, as fold might have returned a
5599 /* Expand both sides into the same slot, hopefully the target of
5600 the ?: expression. We used to check for TARGET_EXPRs here,
5601 but now we sometimes wrap them in NOP_EXPRs so the test would
5603 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5604 result
= get_target_expr_sfinae (result
, complain
);
5605 /* If this expression is an rvalue, but might be mistaken for an
5606 lvalue, we must add a NON_LVALUE_EXPR. */
5607 result
= rvalue (result
);
5610 result
= force_paren_expr (result
);
5615 /* Wrapper for above. */
5618 build_conditional_expr (const op_location_t
&loc
,
5619 tree arg1
, tree arg2
, tree arg3
,
5620 tsubst_flags_t complain
)
5623 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5624 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5625 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5629 /* OPERAND is an operand to an expression. Perform necessary steps
5630 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5634 prep_operand (tree operand
)
5638 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5639 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5640 /* Make sure the template type is instantiated now. */
5641 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5647 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5648 OVERLOAD) to the CANDIDATES, returning an updated list of
5649 CANDIDATES. The ARGS are the arguments provided to the call;
5650 if FIRST_ARG is non-null it is the implicit object argument,
5651 otherwise the first element of ARGS is used if needed. The
5652 EXPLICIT_TARGS are explicit template arguments provided.
5653 TEMPLATE_ONLY is true if only template functions should be
5654 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5655 add_function_candidate. */
5658 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5660 tree explicit_targs
, bool template_only
,
5661 tree conversion_path
, tree access_path
,
5663 struct z_candidate
**candidates
,
5664 tsubst_flags_t complain
)
5667 const vec
<tree
, va_gc
> *non_static_args
;
5668 bool check_list_ctor
= false;
5669 bool check_converting
= false;
5670 unification_kind_t strict
;
5675 /* Precalculate special handling of constructors and conversion ops. */
5676 tree fn
= OVL_FIRST (fns
);
5677 if (DECL_CONV_FN_P (fn
))
5679 check_list_ctor
= false;
5680 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5681 if (flags
& LOOKUP_NO_CONVERSION
)
5682 /* We're doing return_type(x). */
5683 strict
= DEDUCE_CONV
;
5685 /* We're doing x.operator return_type(). */
5686 strict
= DEDUCE_EXACT
;
5687 /* [over.match.funcs] For conversion functions, the function
5688 is considered to be a member of the class of the implicit
5689 object argument for the purpose of defining the type of
5690 the implicit object parameter. */
5691 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5695 if (DECL_CONSTRUCTOR_P (fn
))
5697 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5698 /* For list-initialization we consider explicit constructors
5699 and complain if one is chosen. */
5701 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5702 == LOOKUP_ONLYCONVERTING
);
5704 strict
= DEDUCE_CALL
;
5705 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5709 non_static_args
= args
;
5711 /* Delay creating the implicit this parameter until it is needed. */
5712 non_static_args
= NULL
;
5714 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5718 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5720 if (check_list_ctor
&& !is_list_ctor (fn
))
5723 tree fn_first_arg
= NULL_TREE
;
5724 const vec
<tree
, va_gc
> *fn_args
= args
;
5726 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5728 /* Figure out where the object arg comes from. If this
5729 function is a non-static member and we didn't get an
5730 implicit object argument, move it out of args. */
5731 if (first_arg
== NULL_TREE
)
5735 vec
<tree
, va_gc
> *tempvec
;
5736 vec_alloc (tempvec
, args
->length () - 1);
5737 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5738 tempvec
->quick_push (arg
);
5739 non_static_args
= tempvec
;
5740 first_arg
= (*args
)[0];
5743 fn_first_arg
= first_arg
;
5744 fn_args
= non_static_args
;
5747 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5748 add_template_candidate (candidates
,
5760 else if (!template_only
)
5761 add_function_candidate (candidates
,
5774 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5775 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5778 op_is_ordered (tree_code code
)
5784 return (flag_strong_eval_order
> 1 ? -1 : 0);
5788 return (flag_strong_eval_order
> 1 ? 1 : 0);
5791 // Not overloadable (yet).
5793 // Only one argument.
5800 return (flag_strong_eval_order
? 1 : 0);
5808 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5809 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5810 tsubst_flags_t complain
)
5812 struct z_candidate
*candidates
= 0, *cand
;
5813 vec
<tree
, va_gc
> *arglist
;
5815 tree result
= NULL_TREE
;
5816 bool result_valid_p
= false;
5817 enum tree_code code2
= NOP_EXPR
;
5818 enum tree_code code_orig_arg1
= ERROR_MARK
;
5819 enum tree_code code_orig_arg2
= ERROR_MARK
;
5825 if (error_operand_p (arg1
)
5826 || error_operand_p (arg2
)
5827 || error_operand_p (arg3
))
5828 return error_mark_node
;
5830 bool ismodop
= code
== MODIFY_EXPR
;
5833 code2
= TREE_CODE (arg3
);
5836 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5838 tree arg1_type
= unlowered_expr_type (arg1
);
5839 tree arg2_type
= arg2
? unlowered_expr_type (arg2
) : NULL_TREE
;
5841 arg1
= prep_operand (arg1
);
5843 bool memonly
= false;
5848 case VEC_DELETE_EXPR
:
5850 /* Use build_op_new_call and build_op_delete_call instead. */
5854 /* Use build_op_call instead. */
5857 case TRUTH_ORIF_EXPR
:
5858 case TRUTH_ANDIF_EXPR
:
5859 case TRUTH_AND_EXPR
:
5861 /* These are saved for the sake of warn_logical_operator. */
5862 code_orig_arg1
= TREE_CODE (arg1
);
5863 code_orig_arg2
= TREE_CODE (arg2
);
5871 /* These are saved for the sake of maybe_warn_bool_compare. */
5872 code_orig_arg1
= TREE_CODE (arg1_type
);
5873 code_orig_arg2
= TREE_CODE (arg2_type
);
5876 /* =, ->, [], () must be non-static member functions. */
5878 if (code2
!= NOP_EXPR
)
5890 arg2
= prep_operand (arg2
);
5891 arg3
= prep_operand (arg3
);
5893 if (code
== COND_EXPR
)
5894 /* Use build_conditional_expr instead. */
5896 else if (! OVERLOAD_TYPE_P (arg1_type
)
5897 && (! arg2
|| ! OVERLOAD_TYPE_P (arg2_type
)))
5900 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5902 arg2
= integer_zero_node
;
5903 arg2_type
= integer_type_node
;
5906 vec_alloc (arglist
, 3);
5907 arglist
->quick_push (arg1
);
5908 if (arg2
!= NULL_TREE
)
5909 arglist
->quick_push (arg2
);
5910 if (arg3
!= NULL_TREE
)
5911 arglist
->quick_push (arg3
);
5913 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5914 p
= conversion_obstack_alloc (0);
5916 /* Add namespace-scope operators to the list of functions to
5920 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5921 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5922 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5923 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5924 flags
, &candidates
, complain
);
5929 args
[2] = NULL_TREE
;
5931 /* Add class-member operators to the candidate set. */
5932 if (CLASS_TYPE_P (arg1_type
))
5936 fns
= lookup_fnfields (arg1_type
, fnname
, 1);
5937 if (fns
== error_mark_node
)
5939 result
= error_mark_node
;
5940 goto user_defined_result_ready
;
5943 add_candidates (BASELINK_FUNCTIONS (fns
),
5944 NULL_TREE
, arglist
, NULL_TREE
,
5946 BASELINK_BINFO (fns
),
5947 BASELINK_ACCESS_BINFO (fns
),
5948 flags
, &candidates
, complain
);
5950 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5951 only non-member functions that have type T1 or reference to
5952 cv-qualified-opt T1 for the first argument, if the first argument
5953 has an enumeration type, or T2 or reference to cv-qualified-opt
5954 T2 for the second argument, if the second argument has an
5955 enumeration type. Filter out those that don't match. */
5956 else if (! arg2
|| ! CLASS_TYPE_P (arg2_type
))
5958 struct z_candidate
**candp
, **next
;
5960 for (candp
= &candidates
; *candp
; candp
= next
)
5962 tree parmlist
, parmtype
;
5963 int i
, nargs
= (arg2
? 2 : 1);
5968 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5970 for (i
= 0; i
< nargs
; ++i
)
5972 parmtype
= TREE_VALUE (parmlist
);
5974 if (TYPE_REF_P (parmtype
))
5975 parmtype
= TREE_TYPE (parmtype
);
5976 if (TREE_CODE (unlowered_expr_type (args
[i
])) == ENUMERAL_TYPE
5977 && (same_type_ignoring_top_level_qualifiers_p
5978 (unlowered_expr_type (args
[i
]), parmtype
)))
5981 parmlist
= TREE_CHAIN (parmlist
);
5984 /* No argument has an appropriate type, so remove this
5985 candidate function from the list. */
5988 *candp
= cand
->next
;
5994 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
6001 /* For these, the built-in candidates set is empty
6002 [over.match.oper]/3. We don't want non-strict matches
6003 because exact matches are always possible with built-in
6004 operators. The built-in candidate set for COMPONENT_REF
6005 would be empty too, but since there are no such built-in
6006 operators, we accept non-strict matches for them. */
6015 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
6020 case POSTINCREMENT_EXPR
:
6021 case POSTDECREMENT_EXPR
:
6022 /* Don't try anything fancy if we're not allowed to produce
6024 if (!(complain
& tf_error
))
6025 return error_mark_node
;
6027 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
6028 distinguish between prefix and postfix ++ and
6029 operator++() was used for both, so we allow this with
6033 const char *msg
= (flag_permissive
)
6034 ? G_("no %<%D(int)%> declared for postfix %qs,"
6035 " trying prefix operator instead")
6036 : G_("no %<%D(int)%> declared for postfix %qs");
6037 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
6040 if (!flag_permissive
)
6041 return error_mark_node
;
6043 if (code
== POSTINCREMENT_EXPR
)
6044 code
= PREINCREMENT_EXPR
;
6046 code
= PREDECREMENT_EXPR
;
6047 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
6048 NULL_TREE
, overload
, complain
);
6051 /* The caller will deal with these. */
6056 result_valid_p
= true;
6060 if (complain
& tf_error
)
6062 /* If one of the arguments of the operator represents
6063 an invalid use of member function pointer, try to report
6064 a meaningful error ... */
6065 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
6066 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
6067 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
6068 /* We displayed the error message. */;
6071 /* ... Otherwise, report the more generic
6072 "no matching operator found" error */
6073 auto_diagnostic_group d
;
6074 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
6075 print_z_candidates (loc
, candidates
);
6078 result
= error_mark_node
;
6084 cand
= tourney (candidates
, complain
);
6087 if (complain
& tf_error
)
6089 auto_diagnostic_group d
;
6090 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
6091 print_z_candidates (loc
, candidates
);
6093 result
= error_mark_node
;
6095 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
6098 *overload
= cand
->fn
;
6100 if (resolve_args (arglist
, complain
) == NULL
)
6101 result
= error_mark_node
;
6103 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6105 if (trivial_fn_p (cand
->fn
))
6106 /* There won't be a CALL_EXPR. */;
6107 else if (result
&& result
!= error_mark_node
)
6109 tree call
= extract_call_expr (result
);
6110 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
6112 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
6113 /* This prevents build_new_function_call from discarding this
6114 function during instantiation of the enclosing template. */
6115 KOENIG_LOOKUP_P (call
) = 1;
6117 /* Specify evaluation order as per P0145R2. */
6118 CALL_EXPR_ORDERED_ARGS (call
) = false;
6119 switch (op_is_ordered (code
))
6122 CALL_EXPR_REVERSE_ARGS (call
) = true;
6126 CALL_EXPR_ORDERED_ARGS (call
) = true;
6136 /* Give any warnings we noticed during overload resolution. */
6137 if (cand
->warnings
&& (complain
& tf_warning
))
6139 struct candidate_warning
*w
;
6140 for (w
= cand
->warnings
; w
; w
= w
->next
)
6141 joust (cand
, w
->loser
, 1, complain
);
6144 /* Check for comparison of different enum types. */
6153 if (TREE_CODE (arg1_type
) == ENUMERAL_TYPE
6154 && TREE_CODE (arg2_type
) == ENUMERAL_TYPE
6155 && (TYPE_MAIN_VARIANT (arg1_type
)
6156 != TYPE_MAIN_VARIANT (arg2_type
))
6157 && (complain
& tf_warning
))
6159 warning (OPT_Wenum_compare
,
6160 "comparison between %q#T and %q#T",
6161 arg1_type
, arg2_type
);
6168 /* We need to strip any leading REF_BIND so that bitfields
6169 don't cause errors. This should not remove any important
6170 conversions, because builtins don't apply to class
6171 objects directly. */
6172 conv
= cand
->convs
[0];
6173 if (conv
->kind
== ck_ref_bind
)
6174 conv
= next_conversion (conv
);
6175 arg1
= convert_like (conv
, arg1
, complain
);
6179 conv
= cand
->convs
[1];
6180 if (conv
->kind
== ck_ref_bind
)
6181 conv
= next_conversion (conv
);
6183 arg2
= decay_conversion (arg2
, complain
);
6185 /* We need to call warn_logical_operator before
6186 converting arg2 to a boolean_type, but after
6187 decaying an enumerator to its value. */
6188 if (complain
& tf_warning
)
6189 warn_logical_operator (loc
, code
, boolean_type_node
,
6190 code_orig_arg1
, arg1
,
6191 code_orig_arg2
, arg2
);
6193 arg2
= convert_like (conv
, arg2
, complain
);
6197 conv
= cand
->convs
[2];
6198 if (conv
->kind
== ck_ref_bind
)
6199 conv
= next_conversion (conv
);
6200 convert_like (conv
, arg3
, complain
);
6206 user_defined_result_ready
:
6208 /* Free all the conversions we allocated. */
6209 obstack_free (&conversion_obstack
, p
);
6211 if (result
|| result_valid_p
)
6218 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6221 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6223 case TRUTH_ANDIF_EXPR
:
6224 case TRUTH_ORIF_EXPR
:
6225 case TRUTH_AND_EXPR
:
6227 if (complain
& tf_warning
)
6228 warn_logical_operator (loc
, code
, boolean_type_node
,
6229 code_orig_arg1
, arg1
,
6230 code_orig_arg2
, arg2
);
6238 if ((complain
& tf_warning
)
6239 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6240 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6241 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6242 if (complain
& tf_warning
&& warn_tautological_compare
)
6243 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6248 case TRUNC_DIV_EXPR
:
6253 case TRUNC_MOD_EXPR
:
6257 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6259 case UNARY_PLUS_EXPR
:
6262 case TRUTH_NOT_EXPR
:
6263 case PREINCREMENT_EXPR
:
6264 case POSTINCREMENT_EXPR
:
6265 case PREDECREMENT_EXPR
:
6266 case POSTDECREMENT_EXPR
:
6270 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6273 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6276 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6280 /* The caller will deal with these. */
6292 /* Wrapper for above. */
6295 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6296 tree arg1
, tree arg2
, tree arg3
,
6297 tree
*overload
, tsubst_flags_t complain
)
6300 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6301 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6302 overload
, complain
);
6303 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6307 /* CALL was returned by some call-building function; extract the actual
6308 CALL_EXPR from any bits that have been tacked on, e.g. by
6309 convert_from_reference. */
6312 extract_call_expr (tree call
)
6314 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6315 call
= TREE_OPERAND (call
, 1);
6316 if (REFERENCE_REF_P (call
))
6317 call
= TREE_OPERAND (call
, 0);
6318 if (TREE_CODE (call
) == TARGET_EXPR
)
6319 call
= TARGET_EXPR_INITIAL (call
);
6320 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6321 || TREE_CODE (call
) == AGGR_INIT_EXPR
6322 || call
== error_mark_node
);
6326 /* Returns true if FN has two parameters, of which the second has type
6330 second_parm_is_size_t (tree fn
)
6332 tree t
= FUNCTION_ARG_CHAIN (fn
);
6333 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6336 if (t
== void_list_node
)
6341 /* True if T, an allocation function, has std::align_val_t as its second
6345 aligned_allocation_fn_p (tree t
)
6347 if (!aligned_new_threshold
)
6350 tree a
= FUNCTION_ARG_CHAIN (t
);
6351 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6354 /* True if T is std::destroying_delete_t. */
6357 std_destroying_delete_t_p (tree t
)
6359 return (TYPE_CONTEXT (t
) == std_node
6360 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6363 /* A deallocation function with at least two parameters whose second parameter
6364 type is of type std::destroying_delete_t is a destroying operator delete. A
6365 destroying operator delete shall be a class member function named operator
6366 delete. [ Note: Array deletion cannot use a destroying operator
6367 delete. --end note ] */
6370 destroying_delete_p (tree t
)
6372 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6373 if (!a
|| !TREE_CHAIN (a
))
6375 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6376 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6386 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6387 function (3.7.4.2 [basic.stc.dynamic.deallocation]). If so, and DI is
6388 non-null, also set *DI. */
6391 usual_deallocation_fn_p (tree t
, dealloc_info
*di
)
6393 if (di
) *di
= dealloc_info();
6395 /* A template instance is never a usual deallocation function,
6396 regardless of its signature. */
6397 if (TREE_CODE (t
) == TEMPLATE_DECL
6398 || primary_template_specialization_p (t
))
6401 /* A usual deallocation function is a deallocation function whose parameters
6403 - optionally, a parameter of type std::destroying_delete_t, then
6404 - optionally, a parameter of type std::size_t, then
6405 - optionally, a parameter of type std::align_val_t. */
6406 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6407 tree chain
= FUNCTION_ARG_CHAIN (t
);
6408 if (chain
&& destroying_delete_p (t
))
6410 if (di
) di
->destroying
= TREE_VALUE (chain
);
6411 chain
= TREE_CHAIN (chain
);
6414 && (!global
|| flag_sized_deallocation
)
6415 && same_type_p (TREE_VALUE (chain
), size_type_node
))
6417 if (di
) di
->sized
= true;
6418 chain
= TREE_CHAIN (chain
);
6420 if (chain
&& aligned_new_threshold
6421 && same_type_p (TREE_VALUE (chain
), align_type_node
))
6423 if (di
) di
->aligned
= true;
6424 chain
= TREE_CHAIN (chain
);
6426 return (chain
== void_list_node
);
6429 /* Just return whether FN is a usual deallocation function. */
6432 usual_deallocation_fn_p (tree fn
)
6434 return usual_deallocation_fn_p (fn
, NULL
);
6437 /* Build a call to operator delete. This has to be handled very specially,
6438 because the restrictions on what signatures match are different from all
6439 other call instances. For a normal delete, only a delete taking (void *)
6440 or (void *, size_t) is accepted. For a placement delete, only an exact
6441 match with the placement new is accepted.
6443 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6444 ADDR is the pointer to be deleted.
6445 SIZE is the size of the memory block to be deleted.
6446 GLOBAL_P is true if the delete-expression should not consider
6447 class-specific delete operators.
6448 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6450 If this call to "operator delete" is being generated as part to
6451 deallocate memory allocated via a new-expression (as per [expr.new]
6452 which requires that if the initialization throws an exception then
6453 we call a deallocation function), then ALLOC_FN is the allocation
6457 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6458 bool global_p
, tree placement
,
6459 tree alloc_fn
, tsubst_flags_t complain
)
6461 tree fn
= NULL_TREE
;
6462 tree fns
, fnname
, type
, t
;
6463 dealloc_info di_fn
= { };
6465 if (addr
== error_mark_node
)
6466 return error_mark_node
;
6468 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6470 fnname
= ovl_op_identifier (false, code
);
6472 if (CLASS_TYPE_P (type
)
6473 && COMPLETE_TYPE_P (complete_type (type
))
6477 If the result of the lookup is ambiguous or inaccessible, or if
6478 the lookup selects a placement deallocation function, the
6479 program is ill-formed.
6481 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6483 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6484 if (fns
== error_mark_node
)
6485 return error_mark_node
;
6490 if (fns
== NULL_TREE
)
6491 fns
= lookup_name_nonclass (fnname
);
6493 /* Strip const and volatile from addr. */
6495 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6499 /* "A declaration of a placement deallocation function matches the
6500 declaration of a placement allocation function if it has the same
6501 number of parameters and, after parameter transformations (8.3.5),
6502 all parameter types except the first are identical."
6504 So we build up the function type we want and ask instantiate_type
6505 to get it for us. */
6506 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6507 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6508 t
= build_function_type (void_type_node
, t
);
6510 fn
= instantiate_type (t
, fns
, tf_none
);
6511 if (fn
== error_mark_node
)
6514 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6516 /* "If the lookup finds the two-parameter form of a usual deallocation
6517 function (3.7.4.2) and that function, considered as a placement
6518 deallocation function, would have been selected as a match for the
6519 allocation function, the program is ill-formed." */
6520 if (second_parm_is_size_t (fn
))
6522 const char *const msg1
6523 = G_("exception cleanup for this placement new selects "
6524 "non-placement %<operator delete%>");
6525 const char *const msg2
6526 = G_("%qD is a usual (non-placement) deallocation "
6527 "function in C++14 (or with %<-fsized-deallocation%>)");
6529 /* But if the class has an operator delete (void *), then that is
6530 the usual deallocation function, so we shouldn't complain
6531 about using the operator delete (void *, size_t). */
6532 if (DECL_CLASS_SCOPE_P (fn
))
6533 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6537 if (usual_deallocation_fn_p (elt
)
6538 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6541 /* Before C++14 a two-parameter global deallocation function is
6542 always a placement deallocation function, but warn if
6544 else if (!flag_sized_deallocation
)
6546 if (complain
& tf_warning
)
6548 auto_diagnostic_group d
;
6549 if (warning (OPT_Wc__14_compat
, msg1
))
6550 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6555 if (complain
& tf_warning_or_error
)
6557 auto_diagnostic_group d
;
6558 if (permerror (input_location
, msg1
))
6560 /* Only mention C++14 for namespace-scope delete. */
6561 if (DECL_NAMESPACE_SCOPE_P (fn
))
6562 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6564 inform (DECL_SOURCE_LOCATION (fn
),
6565 "%qD is a usual (non-placement) deallocation "
6570 return error_mark_node
;
6575 /* "Any non-placement deallocation function matches a non-placement
6576 allocation function. If the lookup finds a single matching
6577 deallocation function, that function will be called; otherwise, no
6578 deallocation function will be called." */
6579 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6582 dealloc_info di_elt
;
6583 if (usual_deallocation_fn_p (elt
, &di_elt
))
6592 /* -- If any of the deallocation functions is a destroying
6593 operator delete, all deallocation functions that are not
6594 destroying operator deletes are eliminated from further
6596 if (di_elt
.destroying
!= di_fn
.destroying
)
6598 if (di_elt
.destroying
)
6606 /* -- If the type has new-extended alignment, a function with a
6607 parameter of type std::align_val_t is preferred; otherwise a
6608 function without such a parameter is preferred. If exactly one
6609 preferred function is found, that function is selected and the
6610 selection process terminates. If more than one preferred
6611 function is found, all non-preferred functions are eliminated
6612 from further consideration. */
6613 if (aligned_new_threshold
)
6615 bool want_align
= type_has_new_extended_alignment (type
);
6616 if (di_elt
.aligned
!= di_fn
.aligned
)
6618 if (want_align
== di_elt
.aligned
)
6627 /* -- If the deallocation functions have class scope, the one
6628 without a parameter of type std::size_t is selected. */
6630 if (DECL_CLASS_SCOPE_P (fn
))
6633 /* -- If the type is complete and if, for the second alternative
6634 (delete array) only, the operand is a pointer to a class type
6635 with a non-trivial destructor or a (possibly multi-dimensional)
6636 array thereof, the function with a parameter of type std::size_t
6639 -- Otherwise, it is unspecified whether a deallocation function
6640 with a parameter of type std::size_t is selected. */
6643 want_size
= COMPLETE_TYPE_P (type
);
6644 if (code
== VEC_DELETE_EXPR
6645 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6646 /* We need a cookie to determine the array size. */
6649 gcc_assert (di_fn
.sized
!= di_elt
.sized
);
6650 if (want_size
== di_elt
.sized
)
6658 /* If we have a matching function, call it. */
6661 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6663 /* If the FN is a member function, make sure that it is
6665 if (BASELINK_P (fns
))
6666 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6669 /* Core issue 901: It's ok to new a type with deleted delete. */
6670 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6675 /* The placement args might not be suitable for overload
6676 resolution at this point, so build the call directly. */
6677 int nargs
= call_expr_nargs (placement
);
6678 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6681 for (i
= 1; i
< nargs
; i
++)
6682 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6683 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6684 return error_mark_node
;
6685 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6689 tree destroying
= di_fn
.destroying
;
6692 /* Strip const and volatile from addr but retain the type of the
6694 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6695 rtype
= cv_unqualified (rtype
);
6696 rtype
= TYPE_POINTER_TO (rtype
);
6697 addr
= cp_convert (rtype
, oaddr
, complain
);
6698 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6704 args
->quick_push (addr
);
6706 args
->quick_push (destroying
);
6708 args
->quick_push (size
);
6711 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6712 args
->quick_push (al
);
6714 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6721 If no unambiguous matching deallocation function can be found,
6722 propagating the exception does not cause the object's memory to
6726 if ((complain
& tf_warning
)
6728 warning (0, "no corresponding deallocation function for %qD",
6733 if (complain
& tf_error
)
6734 error ("no suitable %<operator %s%> for %qT",
6735 OVL_OP_INFO (false, code
)->name
, type
);
6736 return error_mark_node
;
6739 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6742 If ISSUE_ERROR is true, then issue an error about the
6743 access, followed by a note showing the declaration.
6744 Otherwise, just show the note. */
6747 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6749 if (TREE_PRIVATE (decl
))
6752 error ("%q#D is private within this context", diag_decl
);
6753 inform (DECL_SOURCE_LOCATION (diag_decl
),
6754 "declared private here");
6756 else if (TREE_PROTECTED (decl
))
6759 error ("%q#D is protected within this context", diag_decl
);
6760 inform (DECL_SOURCE_LOCATION (diag_decl
),
6761 "declared protected here");
6766 error ("%q#D is inaccessible within this context", diag_decl
);
6767 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6771 /* If the current scope isn't allowed to access DECL along
6772 BASETYPE_PATH, give an error. The most derived class in
6773 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6774 the declaration to use in the error diagnostic. */
6777 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6778 tsubst_flags_t complain
, access_failure_info
*afi
)
6780 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6782 if (flag_new_inheriting_ctors
6783 && DECL_INHERITED_CTOR (decl
))
6785 /* 7.3.3/18: The additional constructors are accessible if they would be
6786 accessible when used to construct an object of the corresponding base
6788 decl
= strip_inheriting_ctors (decl
);
6789 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6790 ba_any
, NULL
, complain
);
6793 if (!accessible_p (basetype_path
, decl
, true))
6795 if (flag_new_inheriting_ctors
)
6796 diag_decl
= strip_inheriting_ctors (diag_decl
);
6797 if (complain
& tf_error
)
6798 complain_about_access (decl
, diag_decl
, true);
6800 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6807 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6808 bitwise or of LOOKUP_* values. If any errors are warnings are
6809 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6810 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6814 build_temp (tree expr
, tree type
, int flags
,
6815 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6819 *diagnostic_kind
= DK_UNSPECIFIED
;
6821 /* If the source is a packed field, calling the copy constructor will require
6822 binding the field to the reference parameter to the copy constructor, and
6823 we'll end up with an infinite loop. If we can use a bitwise copy, then
6825 if ((lvalue_kind (expr
) & clk_packed
)
6826 && CLASS_TYPE_P (TREE_TYPE (expr
))
6827 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6828 return get_target_expr_sfinae (expr
, complain
);
6830 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6831 releasing_vec
args (make_tree_vector_single (expr
));
6832 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6833 &args
, type
, flags
, complain
);
6834 if (warningcount
+ werrorcount
> savew
)
6835 *diagnostic_kind
= DK_WARNING
;
6836 else if (errorcount
> savee
)
6837 *diagnostic_kind
= DK_ERROR
;
6841 /* Get any location for EXPR, falling back to input_location.
6843 If the result is in a system header and is the virtual location for
6844 a token coming from the expansion of a macro, unwind it to the
6845 location of the expansion point of the macro (e.g. to avoid the
6846 diagnostic being suppressed for expansions of NULL where "NULL" is
6847 in a system header). */
6850 get_location_for_expr_unwinding_for_system_header (tree expr
)
6852 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6853 loc
= expansion_point_location_if_in_system_header (loc
);
6857 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6858 Also handle a subset of zero as null warnings.
6859 EXPR is implicitly converted to type TOTYPE.
6860 FN and ARGNUM are used for diagnostics. */
6863 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6865 /* Issue warnings about peculiar, but valid, uses of NULL. */
6866 if (TREE_CODE (totype
) != BOOLEAN_TYPE
6867 && ARITHMETIC_TYPE_P (totype
)
6868 && null_node_p (expr
))
6870 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6873 auto_diagnostic_group d
;
6874 if (warning_at (loc
, OPT_Wconversion_null
,
6875 "passing NULL to non-pointer argument %P of %qD",
6877 inform (get_fndecl_argument_location (fn
, argnum
),
6881 warning_at (loc
, OPT_Wconversion_null
,
6882 "converting to non-pointer type %qT from NULL", totype
);
6885 /* Issue warnings if "false" is converted to a NULL pointer */
6886 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6887 && TYPE_PTR_P (totype
))
6889 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6892 auto_diagnostic_group d
;
6893 if (warning_at (loc
, OPT_Wconversion_null
,
6894 "converting %<false%> to pointer type for argument "
6895 "%P of %qD", argnum
, fn
))
6896 inform (get_fndecl_argument_location (fn
, argnum
),
6900 warning_at (loc
, OPT_Wconversion_null
,
6901 "converting %<false%> to pointer type %qT", totype
);
6903 /* Handle zero as null pointer warnings for cases other
6904 than EQ_EXPR and NE_EXPR */
6905 else if ((TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
))
6906 && null_ptr_cst_p (expr
))
6908 location_t loc
= get_location_for_expr_unwinding_for_system_header (expr
);
6909 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6913 /* We gave a diagnostic during a conversion. If this was in the second
6914 standard conversion sequence of a user-defined conversion sequence, say
6915 which user-defined conversion. */
6918 maybe_print_user_conv_context (conversion
*convs
)
6920 if (convs
->user_conv_p
)
6921 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6922 if (t
->kind
== ck_user
)
6924 print_z_candidate (0, N_(" after user-defined conversion:"),
6930 /* Locate the parameter with the given index within FNDECL.
6931 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6932 Return the location of the FNDECL itself if there are problems. */
6935 get_fndecl_argument_location (tree fndecl
, int argnum
)
6937 /* The locations of implicitly-declared functions are likely to be
6938 more meaningful than those of their parameters. */
6939 if (DECL_ARTIFICIAL (fndecl
))
6940 return DECL_SOURCE_LOCATION (fndecl
);
6945 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6946 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6947 i
< argnum
&& param
;
6948 i
++, param
= TREE_CHAIN (param
))
6951 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6952 return the location of FNDECL. */
6954 return DECL_SOURCE_LOCATION (fndecl
);
6956 return DECL_SOURCE_LOCATION (param
);
6959 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6960 within its declaration (or the fndecl itself if something went
6964 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6967 inform (get_fndecl_argument_location (fn
, argnum
),
6968 " initializing argument %P of %qD", argnum
, fn
);
6971 /* Maybe warn about C++20 Conversions to arrays of unknown bound. C is
6972 the conversion, EXPR is the expression we're converting. */
6975 maybe_warn_array_conv (location_t loc
, conversion
*c
, tree expr
)
6977 if (cxx_dialect
>= cxx2a
)
6980 tree type
= TREE_TYPE (expr
);
6981 type
= strip_pointer_operator (type
);
6983 if (TREE_CODE (type
) != ARRAY_TYPE
6984 || TYPE_DOMAIN (type
) == NULL_TREE
)
6987 if (conv_binds_to_array_of_unknown_bound (c
))
6988 pedwarn (loc
, OPT_Wpedantic
, "conversions to arrays of unknown bound "
6989 "are only available with %<-std=c++2a%> or %<-std=gnu++2a%>");
6992 /* Perform the conversions in CONVS on the expression EXPR. FN and
6993 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6994 indicates the `this' argument of a method. INNER is nonzero when
6995 being called to continue a conversion chain. It is negative when a
6996 reference binding will be applied, positive otherwise. If
6997 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6998 conversions will be emitted if appropriate. If C_CAST_P is true,
6999 this conversion is coming from a C-style cast; in that case,
7000 conversions to inaccessible bases are permitted. */
7003 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
7004 bool issue_conversion_warnings
,
7005 bool c_cast_p
, tsubst_flags_t complain
)
7007 tree totype
= convs
->type
;
7008 diagnostic_t diag_kind
;
7010 location_t loc
= cp_expr_loc_or_input_loc (expr
);
7012 if (convs
->bad_p
&& !(complain
& tf_error
))
7013 return error_mark_node
;
7016 && convs
->kind
!= ck_user
7017 && convs
->kind
!= ck_list
7018 && convs
->kind
!= ck_ambig
7019 && (convs
->kind
!= ck_ref_bind
7020 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
7021 && (convs
->kind
!= ck_rvalue
7022 || SCALAR_TYPE_P (totype
))
7023 && convs
->kind
!= ck_base
)
7025 bool complained
= false;
7026 conversion
*t
= convs
;
7028 /* Give a helpful error if this is bad because of excess braces. */
7029 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7030 && SCALAR_TYPE_P (totype
)
7031 && CONSTRUCTOR_NELTS (expr
) > 0
7032 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
7034 complained
= permerror (loc
, "too many braces around initializer "
7036 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7037 && CONSTRUCTOR_NELTS (expr
) == 1)
7038 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7041 /* Give a helpful error if this is bad because a conversion to bool
7042 from std::nullptr_t requires direct-initialization. */
7043 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
7044 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
7045 complained
= permerror (loc
, "converting to %qH from %qI requires "
7046 "direct-initialization",
7047 totype
, TREE_TYPE (expr
));
7049 for (; t
; t
= next_conversion (t
))
7051 if (t
->kind
== ck_user
&& t
->cand
->reason
)
7053 auto_diagnostic_group d
;
7054 complained
= permerror (loc
, "invalid user-defined conversion "
7055 "from %qH to %qI", TREE_TYPE (expr
),
7058 print_z_candidate (loc
, N_("candidate is:"), t
->cand
);
7059 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7060 /*issue_conversion_warnings=*/false,
7063 if (convs
->kind
== ck_ref_bind
)
7064 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
7065 LOOKUP_NORMAL
, NULL_TREE
,
7068 expr
= cp_convert (totype
, expr
, complain
);
7070 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7073 else if (t
->kind
== ck_user
|| !t
->bad_p
)
7075 expr
= convert_like_real (t
, expr
, fn
, argnum
,
7076 /*issue_conversion_warnings=*/false,
7081 else if (t
->kind
== ck_ambig
)
7082 return convert_like_real (t
, expr
, fn
, argnum
,
7083 /*issue_conversion_warnings=*/false,
7086 else if (t
->kind
== ck_identity
)
7091 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
7092 gcc_rich_location
richloc (loc
, &label
);
7093 complained
= permerror (&richloc
,
7094 "invalid conversion from %qH to %qI",
7095 TREE_TYPE (expr
), totype
);
7098 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7100 return cp_convert (totype
, expr
, complain
);
7103 if (issue_conversion_warnings
&& (complain
& tf_warning
))
7104 conversion_null_warnings (totype
, expr
, fn
, argnum
);
7106 switch (convs
->kind
)
7110 struct z_candidate
*cand
= convs
->cand
;
7113 /* We chose the surrogate function from add_conv_candidate, now we
7114 actually need to build the conversion. */
7115 cand
= build_user_type_conversion_1 (totype
, expr
,
7116 LOOKUP_NO_CONVERSION
, complain
);
7118 tree convfn
= cand
->fn
;
7120 /* When converting from an init list we consider explicit
7121 constructors, but actually trying to call one is an error. */
7122 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
7123 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
7124 /* Unless this is for direct-list-initialization. */
7125 && (!CONSTRUCTOR_IS_DIRECT_INIT (expr
) || convs
->need_temporary_p
)
7126 /* And in C++98 a default constructor can't be explicit. */
7127 && cxx_dialect
>= cxx11
)
7129 if (!(complain
& tf_error
))
7130 return error_mark_node
;
7131 location_t loc
= location_of (expr
);
7132 if (CONSTRUCTOR_NELTS (expr
) == 0
7133 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
7135 auto_diagnostic_group d
;
7136 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
7137 "would use explicit constructor %qD",
7139 inform (loc
, "in C++11 and above a default constructor "
7143 error ("converting to %qT from initializer list would use "
7144 "explicit constructor %qD", totype
, convfn
);
7147 /* If we're initializing from {}, it's value-initialization. */
7148 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
7149 && CONSTRUCTOR_NELTS (expr
) == 0
7150 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
)
7151 && !processing_template_decl
)
7153 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
7154 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
7155 return error_mark_node
;
7156 expr
= build_value_init (totype
, complain
);
7157 expr
= get_target_expr_sfinae (expr
, complain
);
7158 if (expr
!= error_mark_node
)
7160 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7161 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
7166 /* We don't know here whether EXPR is being used as an lvalue or
7167 rvalue, but we know it's read. */
7168 mark_exp_read (expr
);
7170 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
7172 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
7175 /* If this is a constructor or a function returning an aggr type,
7176 we need to build up a TARGET_EXPR. */
7177 if (DECL_CONSTRUCTOR_P (convfn
))
7179 expr
= build_cplus_new (totype
, expr
, complain
);
7181 /* Remember that this was list-initialization. */
7182 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
7183 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7189 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
7191 int nelts
= CONSTRUCTOR_NELTS (expr
);
7193 expr
= build_value_init (totype
, complain
);
7194 else if (nelts
== 1)
7195 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7199 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7200 /*read_p=*/true, UNKNOWN_LOCATION
,
7201 /*reject_builtin=*/true);
7203 if (type_unknown_p (expr
))
7204 expr
= instantiate_type (totype
, expr
, complain
);
7205 if (expr
== null_node
7206 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7207 /* If __null has been converted to an integer type, we do not want to
7208 continue to warn about uses of EXPR as an integer, rather than as a
7210 expr
= build_int_cst (totype
, 0);
7213 /* We leave bad_p off ck_ambig because overload resolution considers
7214 it valid, it just fails when we try to perform it. So we need to
7215 check complain here, too. */
7216 if (complain
& tf_error
)
7218 /* Call build_user_type_conversion again for the error. */
7219 int flags
= (convs
->need_temporary_p
7220 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7221 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7222 gcc_assert (seen_error ());
7223 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7225 return error_mark_node
;
7229 /* Conversion to std::initializer_list<T>. */
7230 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7231 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7236 tree val
; unsigned ix
;
7238 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7240 /* Convert all the elements. */
7241 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7243 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
,
7244 argnum
, false, false, complain
);
7245 if (sub
== error_mark_node
)
7247 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7248 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7249 return error_mark_node
;
7250 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
),
7252 if (!TREE_CONSTANT (sub
))
7253 TREE_CONSTANT (new_ctor
) = false;
7255 /* Build up the array. */
7256 elttype
= cp_build_qualified_type
7257 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7258 array
= build_array_of_n_type (elttype
, len
);
7259 array
= finish_compound_literal (array
, new_ctor
, complain
);
7260 /* Take the address explicitly rather than via decay_conversion
7261 to avoid the error about taking the address of a temporary. */
7262 array
= cp_build_addr_expr (array
, complain
);
7265 array
= nullptr_node
;
7267 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7268 if (array
== error_mark_node
)
7269 return error_mark_node
;
7271 /* Build up the initializer_list object. Note: fail gracefully
7272 if the object cannot be completed because, for example, no
7273 definition is provided (c++/80956). */
7274 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7276 return error_mark_node
;
7277 tree field
= next_initializable_field (TYPE_FIELDS (totype
));
7278 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7279 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7280 field
= next_initializable_field (DECL_CHAIN (field
));
7281 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7282 tree new_ctor
= build_constructor (totype
, vec
);
7283 return get_target_expr_sfinae (new_ctor
, complain
);
7287 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7289 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7290 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7291 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7293 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7295 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7298 expr
= reshape_init (totype
, expr
, complain
);
7299 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7301 if (expr
!= error_mark_node
)
7302 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7309 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7310 convs
->kind
== ck_ref_bind
7311 ? issue_conversion_warnings
: false,
7312 c_cast_p
, complain
);
7313 if (expr
== error_mark_node
)
7314 return error_mark_node
;
7316 switch (convs
->kind
)
7319 expr
= decay_conversion (expr
, complain
);
7320 if (expr
== error_mark_node
)
7322 if (complain
& tf_error
)
7324 auto_diagnostic_group d
;
7325 maybe_print_user_conv_context (convs
);
7326 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7328 return error_mark_node
;
7331 if (! MAYBE_CLASS_TYPE_P (totype
))
7334 /* Don't introduce copies when passing arguments along to the inherited
7336 if (current_function_decl
7337 && flag_new_inheriting_ctors
7338 && DECL_INHERITED_CTOR (current_function_decl
))
7341 if (TREE_CODE (expr
) == TARGET_EXPR
7342 && TARGET_EXPR_LIST_INIT_P (expr
))
7343 /* Copy-list-initialization doesn't actually involve a copy. */
7348 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7350 /* We are going to bind a reference directly to a base-class
7351 subobject of EXPR. */
7352 /* Build an expression for `*((base*) &expr)'. */
7353 expr
= convert_to_base (expr
, totype
,
7354 !c_cast_p
, /*nonnull=*/true, complain
);
7358 /* Copy-initialization where the cv-unqualified version of the source
7359 type is the same class as, or a derived class of, the class of the
7360 destination [is treated as direct-initialization]. [dcl.init] */
7361 flags
= LOOKUP_NORMAL
;
7362 if (convs
->user_conv_p
)
7363 /* This conversion is being done in the context of a user-defined
7364 conversion (i.e. the second step of copy-initialization), so
7365 don't allow any more. */
7366 flags
|= LOOKUP_NO_CONVERSION
;
7368 flags
|= LOOKUP_ONLYCONVERTING
;
7369 if (convs
->rvaluedness_matches_p
)
7370 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7371 flags
|= LOOKUP_PREFER_RVALUE
;
7372 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7373 if (diag_kind
&& complain
)
7375 auto_diagnostic_group d
;
7376 maybe_print_user_conv_context (convs
);
7377 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7380 return build_cplus_new (totype
, expr
, complain
);
7384 tree ref_type
= totype
;
7386 /* direct_reference_binding might have inserted a ck_qual under
7387 this ck_ref_bind for the benefit of conversion sequence ranking.
7388 Ignore the conversion; we'll create our own below. */
7389 if (next_conversion (convs
)->kind
== ck_qual
)
7391 gcc_assert (same_type_p (TREE_TYPE (expr
),
7392 next_conversion (convs
)->type
));
7393 /* Strip the cast created by the ck_qual; cp_build_addr_expr
7394 below expects an lvalue. */
7398 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7400 tree extype
= TREE_TYPE (expr
);
7401 auto_diagnostic_group d
;
7402 if (TYPE_REF_IS_RVALUE (ref_type
)
7404 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7405 "lvalue of type %qI", totype
, extype
);
7406 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7407 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7408 error_at (loc
, "cannot bind non-const lvalue reference of "
7409 "type %qH to an rvalue of type %qI", totype
, extype
);
7410 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7412 /* If we're converting from T[] to T[N], don't talk
7413 about discarding qualifiers. (Converting from T[N] to
7414 T[] is allowed by P0388R4.) */
7415 if (TREE_CODE (extype
) == ARRAY_TYPE
7416 && TYPE_DOMAIN (extype
) == NULL_TREE
7417 && TREE_CODE (TREE_TYPE (totype
)) == ARRAY_TYPE
7418 && TYPE_DOMAIN (TREE_TYPE (totype
)) != NULL_TREE
)
7419 error_at (loc
, "cannot bind reference of type %qH to %qI "
7420 "due to different array bounds", totype
, extype
);
7422 error_at (loc
, "binding reference of type %qH to %qI "
7423 "discards qualifiers", totype
, extype
);
7427 maybe_print_user_conv_context (convs
);
7428 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7430 return error_mark_node
;
7432 else if (complain
& tf_warning
)
7433 maybe_warn_array_conv (loc
, convs
, expr
);
7435 /* If necessary, create a temporary.
7437 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7438 that need temporaries, even when their types are reference
7439 compatible with the type of reference being bound, so the
7440 upcoming call to cp_build_addr_expr doesn't fail. */
7441 if (convs
->need_temporary_p
7442 || TREE_CODE (expr
) == CONSTRUCTOR
7443 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7445 /* Otherwise, a temporary of type "cv1 T1" is created and
7446 initialized from the initializer expression using the rules
7447 for a non-reference copy-initialization (8.5). */
7449 tree type
= TREE_TYPE (ref_type
);
7450 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7452 gcc_assert (similar_type_p (type
, next_conversion (convs
)->type
));
7453 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7454 && !TYPE_REF_IS_RVALUE (ref_type
))
7456 /* If the reference is volatile or non-const, we
7457 cannot create a temporary. */
7458 if (lvalue
& clk_bitfield
)
7459 error_at (loc
, "cannot bind bit-field %qE to %qT",
7461 else if (lvalue
& clk_packed
)
7462 error_at (loc
, "cannot bind packed field %qE to %qT",
7465 error_at (loc
, "cannot bind rvalue %qE to %qT",
7467 return error_mark_node
;
7469 /* If the source is a packed field, and we must use a copy
7470 constructor, then building the target expr will require
7471 binding the field to the reference parameter to the
7472 copy constructor, and we'll end up with an infinite
7473 loop. If we can use a bitwise copy, then we'll be
7475 if ((lvalue
& clk_packed
)
7476 && CLASS_TYPE_P (type
)
7477 && type_has_nontrivial_copy_init (type
))
7479 error_at (loc
, "cannot bind packed field %qE to %qT",
7481 return error_mark_node
;
7483 if (lvalue
& clk_bitfield
)
7485 expr
= convert_bitfield_to_declared_type (expr
);
7486 expr
= fold_convert (type
, expr
);
7488 expr
= build_target_expr_with_type (expr
, type
, complain
);
7491 /* Take the address of the thing to which we will bind the
7493 expr
= cp_build_addr_expr (expr
, complain
);
7494 if (expr
== error_mark_node
)
7495 return error_mark_node
;
7497 /* Convert it to a pointer to the type referred to by the
7498 reference. This will adjust the pointer if a derived to
7499 base conversion is being performed. */
7500 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7502 /* Convert the pointer to the desired reference type. */
7503 return build_nop (ref_type
, expr
);
7507 return decay_conversion (expr
, complain
);
7510 /* ??? Should the address of a transaction-safe pointer point to the TM
7511 clone, and this conversion look up the primary function? */
7512 return build_nop (totype
, expr
);
7515 /* Warn about deprecated conversion if appropriate. */
7516 if (complain
& tf_warning
)
7518 string_conv_p (totype
, expr
, 1);
7519 maybe_warn_array_conv (loc
, convs
, expr
);
7525 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7526 /*nonnull=*/false, complain
);
7527 return build_nop (totype
, expr
);
7530 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7531 c_cast_p
, complain
);
7537 if (convs
->check_narrowing
7538 && !check_narrowing (totype
, expr
, complain
,
7539 convs
->check_narrowing_const_only
))
7540 return error_mark_node
;
7542 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7543 if (issue_conversion_warnings
)
7544 expr
= cp_convert_and_check (totype
, expr
, complain
);
7546 expr
= cp_convert (totype
, expr
, complain
);
7551 /* ARG is being passed to a varargs function. Perform any conversions
7552 required. Return the converted value. */
7555 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7557 tree arg_type
= TREE_TYPE (arg
);
7558 location_t loc
= cp_expr_loc_or_input_loc (arg
);
7562 If the argument has integral or enumeration type that is subject
7563 to the integral promotions (_conv.prom_), or a floating-point
7564 type that is subject to the floating-point promotion
7565 (_conv.fpprom_), the value of the argument is converted to the
7566 promoted type before the call. */
7567 if (TREE_CODE (arg_type
) == REAL_TYPE
7568 && (TYPE_PRECISION (arg_type
)
7569 < TYPE_PRECISION (double_type_node
))
7570 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7572 if ((complain
& tf_warning
)
7573 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7574 warning_at (loc
, OPT_Wdouble_promotion
,
7575 "implicit conversion from %qH to %qI when passing "
7576 "argument to function",
7577 arg_type
, double_type_node
);
7578 arg
= convert_to_real_nofold (double_type_node
, arg
);
7580 else if (NULLPTR_TYPE_P (arg_type
))
7581 arg
= null_pointer_node
;
7582 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7584 if (SCOPED_ENUM_P (arg_type
))
7586 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7588 prom
= cp_perform_integral_promotions (prom
, complain
);
7589 if (abi_version_crosses (6)
7590 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7591 && (complain
& tf_warning
))
7592 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through %<...%>"
7593 "as %qT before %<-fabi-version=6%>, %qT after",
7595 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7596 if (!abi_version_at_least (6))
7600 arg
= cp_perform_integral_promotions (arg
, complain
);
7605 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7606 standard conversions are performed. */
7607 arg
= decay_conversion (arg
, complain
);
7609 arg
= require_complete_type_sfinae (arg
, complain
);
7610 arg_type
= TREE_TYPE (arg
);
7612 if (arg
!= error_mark_node
7613 /* In a template (or ill-formed code), we can have an incomplete type
7614 even after require_complete_type_sfinae, in which case we don't know
7615 whether it has trivial copy or not. */
7616 && COMPLETE_TYPE_P (arg_type
)
7617 && !cp_unevaluated_operand
)
7619 /* [expr.call] 5.2.2/7:
7620 Passing a potentially-evaluated argument of class type (Clause 9)
7621 with a non-trivial copy constructor or a non-trivial destructor
7622 with no corresponding parameter is conditionally-supported, with
7623 implementation-defined semantics.
7625 We support it as pass-by-invisible-reference, just like a normal
7628 If the call appears in the context of a sizeof expression,
7629 it is not potentially-evaluated. */
7630 if (type_has_nontrivial_copy_init (arg_type
)
7631 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7633 arg
= force_rvalue (arg
, complain
);
7634 if (complain
& tf_warning
)
7635 warning (OPT_Wconditionally_supported
,
7636 "passing objects of non-trivially-copyable "
7637 "type %q#T through %<...%> is conditionally supported",
7639 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7641 /* Build up a real lvalue-to-rvalue conversion in case the
7642 copy constructor is trivial but not callable. */
7643 else if (CLASS_TYPE_P (arg_type
))
7644 force_rvalue (arg
, complain
);
7651 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7654 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7656 if (processing_template_decl
)
7658 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7659 SET_EXPR_LOCATION (r
, loc
);
7663 type
= complete_type_or_else (type
, NULL_TREE
);
7665 if (expr
== error_mark_node
|| !type
)
7666 return error_mark_node
;
7668 expr
= mark_lvalue_use (expr
);
7670 if (TYPE_REF_P (type
))
7672 error ("cannot receive reference type %qT through %<...%>", type
);
7673 return error_mark_node
;
7676 if (type_has_nontrivial_copy_init (type
)
7677 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7679 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7680 it as pass by invisible reference. */
7681 warning_at (loc
, OPT_Wconditionally_supported
,
7682 "receiving objects of non-trivially-copyable type %q#T "
7683 "through %<...%> is conditionally-supported", type
);
7685 tree ref
= cp_build_reference_type (type
, false);
7686 expr
= build_va_arg (loc
, expr
, ref
);
7687 return convert_from_reference (expr
);
7690 tree ret
= build_va_arg (loc
, expr
, type
);
7691 if (CLASS_TYPE_P (type
))
7692 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7693 know how to handle it. */
7694 ret
= get_target_expr (ret
);
7698 /* TYPE has been given to va_arg. Apply the default conversions which
7699 would have happened when passed via ellipsis. Return the promoted
7700 type, or the passed type if there is no change. */
7703 cxx_type_promotes_to (tree type
)
7707 /* Perform the array-to-pointer and function-to-pointer
7709 type
= type_decays_to (type
);
7711 promote
= type_promotes_to (type
);
7712 if (same_type_p (type
, promote
))
7718 /* ARG is a default argument expression being passed to a parameter of
7719 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7720 zero-based argument number. Do any required conversions. Return
7721 the converted value. */
7723 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7725 push_defarg_context (tree fn
)
7726 { vec_safe_push (default_arg_context
, fn
); }
7729 pop_defarg_context (void)
7730 { default_arg_context
->pop (); }
7733 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7734 tsubst_flags_t complain
)
7739 /* See through clones. */
7740 fn
= DECL_ORIGIN (fn
);
7741 /* And inheriting ctors. */
7742 if (flag_new_inheriting_ctors
)
7743 fn
= strip_inheriting_ctors (fn
);
7745 /* Detect recursion. */
7746 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7749 if (complain
& tf_error
)
7750 error ("recursive evaluation of default argument for %q#D", fn
);
7751 return error_mark_node
;
7754 /* If the ARG is an unparsed default argument expression, the
7755 conversion cannot be performed. */
7756 if (TREE_CODE (arg
) == DEFERRED_PARSE
)
7758 if (complain
& tf_error
)
7759 error ("call to %qD uses the default argument for parameter %P, which "
7760 "is not yet defined", fn
, parmnum
);
7761 return error_mark_node
;
7764 push_defarg_context (fn
);
7766 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7767 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7773 The names in the expression are bound, and the semantic
7774 constraints are checked, at the point where the default
7775 expressions appears.
7777 we must not perform access checks here. */
7778 push_deferring_access_checks (dk_no_check
);
7779 /* We must make a copy of ARG, in case subsequent processing
7780 alters any part of it. */
7781 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7783 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7784 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7786 arg
= convert_for_arg_passing (type
, arg
, complain
);
7787 pop_deferring_access_checks();
7789 pop_defarg_context ();
7794 /* Returns the type which will really be used for passing an argument of
7798 type_passed_as (tree type
)
7800 /* Pass classes with copy ctors by invisible reference. */
7801 if (TREE_ADDRESSABLE (type
))
7803 type
= build_reference_type (type
);
7804 /* There are no other pointers to this temporary. */
7805 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7807 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7808 && INTEGRAL_TYPE_P (type
)
7809 && COMPLETE_TYPE_P (type
)
7810 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7811 type
= integer_type_node
;
7816 /* Actually perform the appropriate conversion. */
7819 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7823 /* If VAL is a bitfield, then -- since it has already been converted
7824 to TYPE -- it cannot have a precision greater than TYPE.
7826 If it has a smaller precision, we must widen it here. For
7827 example, passing "int f:3;" to a function expecting an "int" will
7828 not result in any conversion before this point.
7830 If the precision is the same we must not risk widening. For
7831 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7832 often have type "int", even though the C++ type for the field is
7833 "long long". If the value is being passed to a function
7834 expecting an "int", then no conversions will be required. But,
7835 if we call convert_bitfield_to_declared_type, the bitfield will
7836 be converted to "long long". */
7837 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7839 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7840 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7842 if (val
== error_mark_node
)
7844 /* Pass classes with copy ctors by invisible reference. */
7845 else if (TREE_ADDRESSABLE (type
))
7846 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7847 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7848 && INTEGRAL_TYPE_P (type
)
7849 && COMPLETE_TYPE_P (type
)
7850 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7851 val
= cp_perform_integral_promotions (val
, complain
);
7852 if (complain
& tf_warning
)
7854 if (warn_suggest_attribute_format
)
7856 tree rhstype
= TREE_TYPE (val
);
7857 const enum tree_code coder
= TREE_CODE (rhstype
);
7858 const enum tree_code codel
= TREE_CODE (type
);
7859 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7861 && check_missing_format_attribute (type
, rhstype
))
7862 warning (OPT_Wsuggest_attribute_format
,
7863 "argument of function call might be a candidate "
7864 "for a format attribute");
7866 maybe_warn_parm_abi (type
, cp_expr_loc_or_input_loc (val
));
7869 if (complain
& tf_warning
)
7870 warn_for_address_or_pointer_of_packed_member (type
, val
);
7875 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7876 which just decay_conversion or no conversions at all should be done.
7877 This is true for some builtins which don't act like normal functions.
7878 Return 2 if no conversions at all should be done, 1 if just
7879 decay_conversion. Return 3 for special treatment of the 3rd argument
7880 for __builtin_*_overflow_p. */
7883 magic_varargs_p (tree fn
)
7885 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7886 switch (DECL_FUNCTION_CODE (fn
))
7888 case BUILT_IN_CLASSIFY_TYPE
:
7889 case BUILT_IN_CONSTANT_P
:
7890 case BUILT_IN_NEXT_ARG
:
7891 case BUILT_IN_VA_START
:
7894 case BUILT_IN_ADD_OVERFLOW_P
:
7895 case BUILT_IN_SUB_OVERFLOW_P
:
7896 case BUILT_IN_MUL_OVERFLOW_P
:
7900 return lookup_attribute ("type generic",
7901 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7907 /* Returns the decl of the dispatcher function if FN is a function version. */
7910 get_function_version_dispatcher (tree fn
)
7912 tree dispatcher_decl
= NULL
;
7914 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7915 && DECL_FUNCTION_VERSIONED (fn
));
7917 gcc_assert (targetm
.get_function_versions_dispatcher
);
7918 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7920 if (dispatcher_decl
== NULL
)
7922 error_at (input_location
, "use of multiversioned function "
7923 "without a default");
7927 retrofit_lang_decl (dispatcher_decl
);
7928 gcc_assert (dispatcher_decl
!= NULL
);
7929 return dispatcher_decl
;
7932 /* fn is a function version dispatcher that is marked used. Mark all the
7933 semantically identical function versions it will dispatch as used. */
7936 mark_versions_used (tree fn
)
7938 struct cgraph_node
*node
;
7939 struct cgraph_function_version_info
*node_v
;
7940 struct cgraph_function_version_info
*it_v
;
7942 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7944 node
= cgraph_node::get (fn
);
7948 gcc_assert (node
->dispatcher_function
);
7950 node_v
= node
->function_version ();
7954 /* All semantically identical versions are chained. Traverse and mark each
7955 one of them as used. */
7956 it_v
= node_v
->next
;
7957 while (it_v
!= NULL
)
7959 mark_used (it_v
->this_node
->decl
);
7964 /* Build a call to "the copy constructor" for the type of A, even if it
7965 wouldn't be selected by normal overload resolution. Used for
7969 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7971 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7972 tree binfo
= TYPE_BINFO (ctype
);
7973 tree copy
= get_copy_ctor (ctype
, complain
);
7974 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7975 tree ob
= build_dummy_object (ctype
);
7976 releasing_vec
args (make_tree_vector_single (a
));
7977 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7978 LOOKUP_NORMAL
, NULL
, complain
);
7982 /* Return true iff T refers to a base field. */
7985 is_base_field_ref (tree t
)
7988 if (TREE_CODE (t
) == ADDR_EXPR
)
7989 t
= TREE_OPERAND (t
, 0);
7990 if (TREE_CODE (t
) == COMPONENT_REF
)
7991 t
= TREE_OPERAND (t
, 1);
7992 if (TREE_CODE (t
) == FIELD_DECL
)
7993 return DECL_FIELD_IS_BASE (t
);
7997 /* We can't elide a copy from a function returning by value to a base
7998 subobject, as the callee might clobber tail padding. Return true iff this
7999 could be that case. */
8002 unsafe_copy_elision_p (tree target
, tree exp
)
8004 /* Copy elision only happens with a TARGET_EXPR. */
8005 if (TREE_CODE (exp
) != TARGET_EXPR
)
8007 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
8008 /* It's safe to elide the copy for a class with no tail padding. */
8009 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
8011 /* It's safe to elide the copy if we aren't initializing a base object. */
8012 if (!is_base_field_ref (target
))
8014 tree init
= TARGET_EXPR_INITIAL (exp
);
8015 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
8016 while (TREE_CODE (init
) == COMPOUND_EXPR
)
8017 init
= TREE_OPERAND (init
, 1);
8018 if (TREE_CODE (init
) == COND_EXPR
)
8020 /* We'll end up copying from each of the arms of the COND_EXPR directly
8021 into the target, so look at them. */
8022 if (tree op
= TREE_OPERAND (init
, 1))
8023 if (unsafe_copy_elision_p (target
, op
))
8025 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
8027 return (TREE_CODE (init
) == AGGR_INIT_EXPR
8028 && !AGGR_INIT_VIA_CTOR_P (init
));
8031 /* True iff C is a conversion that binds a reference to a prvalue. */
8034 conv_binds_ref_to_prvalue (conversion
*c
)
8036 if (c
->kind
!= ck_ref_bind
)
8038 if (c
->need_temporary_p
)
8041 c
= next_conversion (c
);
8043 if (c
->kind
== ck_rvalue
)
8045 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
8047 if (c
->kind
== ck_identity
&& c
->u
.expr
8048 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
8054 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
8055 class type or a pointer to class type. */
8058 build_trivial_dtor_call (tree instance
)
8060 gcc_assert (!is_dummy_object (instance
));
8062 if (!flag_lifetime_dse
)
8065 return fold_convert (void_type_node
, instance
);
8068 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
8070 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
8072 instance
= cp_build_fold_indirect_ref (instance
);
8075 /* A trivial destructor should still clobber the object. */
8076 tree clobber
= build_clobber (TREE_TYPE (instance
));
8077 return build2 (MODIFY_EXPR
, void_type_node
,
8081 /* Subroutine of the various build_*_call functions. Overload resolution
8082 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
8083 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
8084 bitmask of various LOOKUP_* flags which apply to the call itself. */
8087 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
8090 const vec
<tree
, va_gc
> *args
= cand
->args
;
8091 tree first_arg
= cand
->first_arg
;
8092 conversion
**convs
= cand
->convs
;
8094 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
8099 unsigned int arg_index
= 0;
8103 bool already_used
= false;
8105 /* In a template, there is no need to perform all of the work that
8106 is normally done. We are only interested in the type of the call
8107 expression, i.e., the return type of the function. Any semantic
8108 errors will be deferred until the template is instantiated. */
8109 if (processing_template_decl
)
8113 const tree
*argarray
;
8116 if (undeduced_auto_decl (fn
))
8117 mark_used (fn
, complain
);
8119 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
8123 return_type
= TREE_TYPE (TREE_TYPE (fn
));
8124 nargs
= vec_safe_length (args
);
8125 if (first_arg
== NULL_TREE
)
8126 argarray
= args
->address ();
8134 alcarray
= XALLOCAVEC (tree
, nargs
);
8135 alcarray
[0] = build_this (first_arg
);
8136 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
8137 alcarray
[ix
+ 1] = arg
;
8138 argarray
= alcarray
;
8141 addr
= build_addr_func (fn
, complain
);
8142 if (addr
== error_mark_node
)
8143 return error_mark_node
;
8144 expr
= build_call_array_loc (input_location
, return_type
,
8145 addr
, nargs
, argarray
);
8146 if (TREE_THIS_VOLATILE (fn
) && cfun
)
8147 current_function_returns_abnormally
= 1;
8148 return convert_from_reference (expr
);
8151 /* Give any warnings we noticed during overload resolution. */
8152 if (cand
->warnings
&& (complain
& tf_warning
))
8154 struct candidate_warning
*w
;
8155 for (w
= cand
->warnings
; w
; w
= w
->next
)
8156 joust (cand
, w
->loser
, 1, complain
);
8159 /* Core issue 2327: P0135 doesn't say how to handle the case where the
8160 argument to the copy constructor ends up being a prvalue after
8161 conversion. Let's do the normal processing, but pretend we aren't
8162 actually using the copy constructor. */
8163 bool force_elide
= false;
8164 if (cxx_dialect
>= cxx17
8165 && cand
->num_convs
== 1
8166 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
8167 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8168 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8169 && conv_binds_ref_to_prvalue (convs
[0]))
8172 goto not_really_used
;
8175 /* OK, we're actually calling this inherited constructor; set its deletedness
8176 appropriately. We can get away with doing this here because calling is
8177 the only way to refer to a constructor. */
8178 if (DECL_INHERITED_CTOR (fn
))
8179 deduce_inheriting_ctor (fn
);
8181 /* Make =delete work with SFINAE. */
8182 if (DECL_DELETED_FN (fn
))
8184 if (complain
& tf_error
)
8186 return error_mark_node
;
8189 if (DECL_FUNCTION_MEMBER_P (fn
))
8192 /* If FN is a template function, two cases must be considered.
8197 template <class T> void f();
8199 template <class T> struct B {
8203 struct C : A, B<int> {
8205 using B<int>::g; // #2
8208 In case #1 where `A::f' is a member template, DECL_ACCESS is
8209 recorded in the primary template but not in its specialization.
8210 We check access of FN using its primary template.
8212 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
8213 because it is a member of class template B, DECL_ACCESS is
8214 recorded in the specialization `B<int>::g'. We cannot use its
8215 primary template because `B<T>::g' and `B<int>::g' may have
8216 different access. */
8217 if (DECL_TEMPLATE_INFO (fn
)
8218 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
8219 access_fn
= DECL_TI_TEMPLATE (fn
);
8222 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
8224 return error_mark_node
;
8227 /* If we're checking for implicit delete, don't bother with argument
8229 if (flags
& LOOKUP_SPECULATIVE
)
8231 if (cand
->viable
== 1)
8233 else if (!(complain
& tf_error
))
8234 /* Reject bad conversions now. */
8235 return error_mark_node
;
8236 /* else continue to get conversion error. */
8241 /* N3276 magic doesn't apply to nested calls. */
8242 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8243 complain
&= ~tf_decltype
;
8244 /* No-Cleanup doesn't apply to nested calls either. */
8245 tsubst_flags_t no_cleanup_complain
= complain
;
8246 complain
&= ~tf_no_cleanup
;
8248 /* Find maximum size of vector to hold converted arguments. */
8249 parmlen
= list_length (parm
);
8250 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8251 if (parmlen
> nargs
)
8253 argarray
= XALLOCAVEC (tree
, nargs
);
8255 /* The implicit parameters to a constructor are not considered by overload
8256 resolution, and must be of the proper type. */
8257 if (DECL_CONSTRUCTOR_P (fn
))
8260 if (first_arg
!= NULL_TREE
)
8262 object_arg
= first_arg
;
8263 first_arg
= NULL_TREE
;
8267 object_arg
= (*args
)[arg_index
];
8270 argarray
[j
++] = build_this (object_arg
);
8271 parm
= TREE_CHAIN (parm
);
8272 /* We should never try to call the abstract constructor. */
8273 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8275 if (DECL_HAS_VTT_PARM_P (fn
))
8277 argarray
[j
++] = (*args
)[arg_index
];
8279 parm
= TREE_CHAIN (parm
);
8282 if (flags
& LOOKUP_PREFER_RVALUE
)
8284 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8285 the first parameter of the selected constructor is not an rvalue
8286 reference to the object's type (possibly cv-qualified)...." */
8287 gcc_assert (!(complain
& tf_error
));
8288 tree ptype
= convs
[0]->type
;
8289 if (!TYPE_REF_P (ptype
)
8290 || !TYPE_REF_IS_RVALUE (ptype
)
8291 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8292 return error_mark_node
;
8295 /* Bypass access control for 'this' parameter. */
8296 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8298 tree parmtype
= TREE_VALUE (parm
);
8299 tree arg
= build_this (first_arg
!= NULL_TREE
8301 : (*args
)[arg_index
]);
8302 tree argtype
= TREE_TYPE (arg
);
8306 if (arg
== error_mark_node
)
8307 return error_mark_node
;
8309 if (convs
[i
]->bad_p
)
8311 if (complain
& tf_error
)
8313 auto_diagnostic_group d
;
8314 if (permerror (input_location
, "passing %qT as %<this%> "
8315 "argument discards qualifiers",
8316 TREE_TYPE (argtype
)))
8317 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8320 return error_mark_node
;
8323 /* Optimize away vtable lookup if we know that this
8324 function can't be overridden. We need to check if
8325 the context and the type where we found fn are the same,
8326 actually FN might be defined in a different class
8327 type because of a using-declaration. In this case, we
8328 do not want to perform a non-virtual call. Note that
8329 resolves_to_fixed_type_p checks CLASSTYPE_FINAL too. */
8330 if (DECL_FINAL_P (fn
)
8331 || (resolves_to_fixed_type_p (arg
, 0)
8332 && same_type_ignoring_top_level_qualifiers_p
8333 (DECL_CONTEXT (fn
), BINFO_TYPE (cand
->conversion_path
))))
8334 flags
|= LOOKUP_NONVIRTUAL
;
8336 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8337 X is called for an object that is not of type X, or of a type
8338 derived from X, the behavior is undefined.
8340 So we can assume that anything passed as 'this' is non-null, and
8341 optimize accordingly. */
8342 gcc_assert (TYPE_PTR_P (parmtype
));
8343 /* Convert to the base in which the function was declared. */
8344 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8345 converted_arg
= build_base_path (PLUS_EXPR
,
8347 cand
->conversion_path
,
8349 /* Check that the base class is accessible. */
8350 if (!accessible_base_p (TREE_TYPE (argtype
),
8351 BINFO_TYPE (cand
->conversion_path
), true))
8353 if (complain
& tf_error
)
8354 error ("%qT is not an accessible base of %qT",
8355 BINFO_TYPE (cand
->conversion_path
),
8356 TREE_TYPE (argtype
));
8358 return error_mark_node
;
8360 /* If fn was found by a using declaration, the conversion path
8361 will be to the derived class, not the base declaring fn. We
8362 must convert from derived to base. */
8363 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8364 TREE_TYPE (parmtype
), ba_unique
,
8366 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8367 base_binfo
, 1, complain
);
8369 argarray
[j
++] = converted_arg
;
8370 parm
= TREE_CHAIN (parm
);
8371 if (first_arg
!= NULL_TREE
)
8372 first_arg
= NULL_TREE
;
8379 gcc_assert (first_arg
== NULL_TREE
);
8380 for (; arg_index
< vec_safe_length (args
) && parm
;
8381 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8383 tree type
= TREE_VALUE (parm
);
8384 tree arg
= (*args
)[arg_index
];
8385 bool conversion_warning
= true;
8389 /* If the argument is NULL and used to (implicitly) instantiate a
8390 template function (and bind one of the template arguments to
8391 the type of 'long int'), we don't want to warn about passing NULL
8392 to non-pointer argument.
8393 For example, if we have this template function:
8395 template<typename T> void func(T x) {}
8397 we want to warn (when -Wconversion is enabled) in this case:
8403 but not in this case:
8409 if (null_node_p (arg
)
8410 && DECL_TEMPLATE_INFO (fn
)
8411 && cand
->template_decl
8412 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8413 conversion_warning
= false;
8415 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8416 knows not to allow any more UDCs. This needs to happen after we
8417 process cand->warnings. */
8418 if (flags
& LOOKUP_NO_CONVERSION
)
8419 conv
->user_conv_p
= true;
8421 tsubst_flags_t arg_complain
= complain
;
8422 if (!conversion_warning
)
8423 arg_complain
&= ~tf_warning
;
8425 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8427 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8429 if (val
== error_mark_node
)
8430 return error_mark_node
;
8432 argarray
[j
++] = val
;
8435 /* Default arguments */
8436 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8438 if (TREE_VALUE (parm
) == error_mark_node
)
8439 return error_mark_node
;
8440 val
= convert_default_arg (TREE_VALUE (parm
),
8441 TREE_PURPOSE (parm
),
8444 if (val
== error_mark_node
)
8445 return error_mark_node
;
8446 argarray
[j
++] = val
;
8450 int magic
= magic_varargs_p (fn
);
8451 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8453 tree a
= (*args
)[arg_index
];
8454 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8456 /* Do no conversions for certain magic varargs. */
8457 a
= mark_type_use (a
);
8458 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8459 return error_mark_node
;
8461 else if (magic
!= 0)
8462 /* For other magic varargs only do decay_conversion. */
8463 a
= decay_conversion (a
, complain
);
8464 else if (DECL_CONSTRUCTOR_P (fn
)
8465 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8468 /* Avoid infinite recursion trying to call A(...). */
8469 if (complain
& tf_error
)
8470 /* Try to call the actual copy constructor for a good error. */
8471 call_copy_ctor (a
, complain
);
8472 return error_mark_node
;
8475 a
= convert_arg_to_ellipsis (a
, complain
);
8476 if (a
== error_mark_node
)
8477 return error_mark_node
;
8481 gcc_assert (j
<= nargs
);
8484 /* Avoid to do argument-transformation, if warnings for format, and for
8485 nonnull are disabled. Just in case that at least one of them is active
8486 the check_function_arguments function might warn about something. */
8488 bool warned_p
= false;
8491 || warn_suggest_attribute_format
8494 tree
*fargs
= (!nargs
? argarray
8495 : (tree
*) alloca (nargs
* sizeof (tree
)));
8496 for (j
= 0; j
< nargs
; j
++)
8498 /* For -Wformat undo the implicit passing by hidden reference
8499 done by convert_arg_to_ellipsis. */
8500 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8501 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8502 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8504 fargs
[j
] = argarray
[j
];
8507 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8508 nargs
, fargs
, NULL
);
8511 if (DECL_INHERITED_CTOR (fn
))
8513 /* Check for passing ellipsis arguments to an inherited constructor. We
8514 could handle this by open-coding the inherited constructor rather than
8515 defining it, but let's not bother now. */
8516 if (!cp_unevaluated_operand
8518 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8520 if (complain
& tf_error
)
8522 sorry ("passing arguments to ellipsis of inherited constructor "
8524 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8526 return error_mark_node
;
8529 /* A base constructor inheriting from a virtual base doesn't get the
8530 inherited arguments, just this and __vtt. */
8531 if (ctor_omit_inherited_parms (fn
))
8535 /* Avoid actually calling copy constructors and copy assignment operators,
8538 if (! flag_elide_constructors
&& !force_elide
)
8539 /* Do things the hard way. */;
8540 else if (cand
->num_convs
== 1
8541 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8542 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8543 /* It's unsafe to elide the constructor when handling
8544 a noexcept-expression, it may evaluate to the wrong
8545 value (c++/53025). */
8546 && (force_elide
|| cp_noexcept_operand
== 0))
8549 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8551 bool trivial
= trivial_fn_p (fn
);
8553 /* Pull out the real argument, disregarding const-correctness. */
8555 /* Strip the reference binding for the constructor parameter. */
8556 if (CONVERT_EXPR_P (targ
)
8557 && TYPE_REF_P (TREE_TYPE (targ
)))
8558 targ
= TREE_OPERAND (targ
, 0);
8559 /* But don't strip any other reference bindings; binding a temporary to a
8560 reference prevents copy elision. */
8561 while ((CONVERT_EXPR_P (targ
)
8562 && !TYPE_REF_P (TREE_TYPE (targ
)))
8563 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8564 targ
= TREE_OPERAND (targ
, 0);
8565 if (TREE_CODE (targ
) == ADDR_EXPR
)
8567 targ
= TREE_OPERAND (targ
, 0);
8568 if (!same_type_ignoring_top_level_qualifiers_p
8569 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8578 arg
= cp_build_fold_indirect_ref (arg
);
8580 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8582 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8583 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8585 /* It's from binding the ref parm to a packed field. */
8586 || convs
[0]->need_temporary_p
8588 /* See unsafe_copy_elision_p. */
8589 || DECL_BASE_CONSTRUCTOR_P (fn
));
8592 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8593 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8595 /* [class.copy]: the copy constructor is implicitly defined even if the
8596 implementation elided its use. But don't warn about deprecation when
8597 eliding a temporary, as then no copy is actually performed. */
8598 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8600 /* The language says this isn't called. */;
8603 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8604 return error_mark_node
;
8605 already_used
= true;
8608 cp_warn_deprecated_use (fn
, complain
);
8610 /* If we're creating a temp and we already have one, don't create a
8611 new one. If we're not creating a temp but we get one, use
8612 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8613 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8614 temp or an INIT_EXPR otherwise. */
8615 if (is_dummy_object (fa
))
8617 if (TREE_CODE (arg
) == TARGET_EXPR
)
8620 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8622 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8625 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8627 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8631 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8632 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8633 && trivial_fn_p (fn
))
8635 tree to
= cp_stabilize_reference
8636 (cp_build_fold_indirect_ref (argarray
[0]));
8637 tree type
= TREE_TYPE (to
);
8638 tree as_base
= CLASSTYPE_AS_BASE (type
);
8639 tree arg
= argarray
[1];
8640 location_t loc
= cp_expr_loc_or_input_loc (arg
);
8642 if (is_really_empty_class (type
, /*ignore_vptr*/true))
8644 /* Avoid copying empty classes. */
8645 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8646 TREE_NO_WARNING (val
) = 1;
8648 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8650 if (is_std_init_list (type
)
8651 && conv_binds_ref_to_prvalue (convs
[1]))
8652 warning_at (loc
, OPT_Winit_list_lifetime
,
8653 "assignment from temporary %<initializer_list%> does "
8654 "not extend the lifetime of the underlying array");
8655 arg
= cp_build_fold_indirect_ref (arg
);
8656 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8660 /* We must only copy the non-tail padding parts. */
8662 tree array_type
, alias_set
;
8664 arg2
= TYPE_SIZE_UNIT (as_base
);
8665 arg0
= cp_build_addr_expr (to
, complain
);
8667 array_type
= build_array_type (unsigned_char_type_node
,
8669 (size_binop (MINUS_EXPR
,
8670 arg2
, size_int (1))));
8671 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8672 t
= build2 (MODIFY_EXPR
, void_type_node
,
8673 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8674 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8675 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8676 TREE_NO_WARNING (val
) = 1;
8679 cp_warn_deprecated_use (fn
, complain
);
8683 else if (trivial_fn_p (fn
))
8685 if (DECL_DESTRUCTOR_P (fn
))
8686 return build_trivial_dtor_call (argarray
[0]);
8687 else if (default_ctor_p (fn
))
8689 if (is_dummy_object (argarray
[0]))
8690 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8691 no_cleanup_complain
);
8693 return cp_build_fold_indirect_ref (argarray
[0]);
8697 gcc_assert (!force_elide
);
8700 && !mark_used (fn
, complain
))
8701 return error_mark_node
;
8703 /* Warn if the built-in writes to an object of a non-trivial type. */
8704 if (warn_class_memaccess
8705 && vec_safe_length (args
) >= 2
8706 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8707 maybe_warn_class_memaccess (input_location
, fn
, args
);
8709 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8712 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8714 ba_any
, NULL
, complain
);
8715 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8717 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8719 if (TREE_SIDE_EFFECTS (argarray
[0]))
8720 argarray
[0] = save_expr (argarray
[0]);
8721 t
= build_pointer_type (TREE_TYPE (fn
));
8722 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8727 fn
= build_addr_func (fn
, complain
);
8728 if (fn
== error_mark_node
)
8729 return error_mark_node
;
8732 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8733 if (call
== error_mark_node
)
8735 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8737 tree c
= extract_call_expr (call
);
8738 /* build_new_op_1 will clear this when appropriate. */
8739 CALL_EXPR_ORDERED_ARGS (c
) = true;
8743 tree c
= extract_call_expr (call
);
8744 if (TREE_CODE (c
) == CALL_EXPR
)
8745 TREE_NO_WARNING (c
) = 1;
8753 /* Return the DECL of the first non-static subobject of class TYPE
8754 that satisfies the predicate PRED or null if none can be found. */
8756 template <class Predicate
>
8758 first_non_static_field (tree type
, Predicate pred
)
8760 if (!type
|| !CLASS_TYPE_P (type
))
8763 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8765 if (TREE_CODE (field
) != FIELD_DECL
)
8767 if (TREE_STATIC (field
))
8775 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8776 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8778 tree base
= TREE_TYPE (base_binfo
);
8781 if (tree field
= first_non_static_field (base
, pred
))
8788 struct NonPublicField
8790 bool operator() (const_tree t
)
8792 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8796 /* Return the DECL of the first non-public subobject of class TYPE
8797 or null if none can be found. */
8800 first_non_public_field (tree type
)
8802 return first_non_static_field (type
, NonPublicField ());
8805 struct NonTrivialField
8807 bool operator() (const_tree t
)
8809 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8813 /* Return the DECL of the first non-trivial subobject of class TYPE
8814 or null if none can be found. */
8817 first_non_trivial_field (tree type
)
8819 return first_non_static_field (type
, NonTrivialField ());
8822 } /* unnamed namespace */
8824 /* Return true if all copy and move assignment operator overloads for
8825 class TYPE are trivial and at least one of them is not deleted and,
8826 when ACCESS is set, accessible. Return false otherwise. Set
8827 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8828 copy or move assignment. */
8831 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8833 tree fns
= get_class_binding (type
, assign_op_identifier
);
8834 bool all_trivial
= true;
8836 /* Iterate over overloads of the assignment operator, checking
8837 accessible copy assignments for triviality. */
8839 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8843 /* Skip operators that aren't copy assignments. */
8847 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8848 || accessible_p (TYPE_BINFO (type
), f
, true));
8850 /* Skip template assignment operators and deleted functions. */
8851 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8857 if (!accessible
|| !trivial_fn_p (f
))
8858 all_trivial
= false;
8860 /* Break early when both properties have been determined. */
8861 if (*hasassign
&& !all_trivial
)
8865 /* Return true if they're all trivial and one of the expressions
8866 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8867 tree ref
= cp_build_reference_type (type
, false);
8869 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8870 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8873 /* Return true if all copy and move ctor overloads for class TYPE are
8874 trivial and at least one of them is not deleted and, when ACCESS is
8875 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8876 to true when the TYPE has a (not necessarily trivial) default and copy
8877 (or move) ctor, respectively. */
8880 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8882 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8883 bool all_trivial
= true;
8885 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8889 /* Skip template constructors. */
8890 if (TREE_CODE (f
) != FUNCTION_DECL
)
8893 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8895 /* Skip ctors other than default, copy, and move. */
8896 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8899 if (DECL_DELETED_FN (f
))
8902 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8903 || accessible_p (TYPE_BINFO (type
), f
, true));
8906 hasctor
[cpy_or_move_ctor_p
] = true;
8908 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8909 all_trivial
= false;
8911 /* Break early when both properties have been determined. */
8912 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8919 /* Issue a warning on a call to the built-in function FNDECL if it is
8920 a raw memory write whose destination is not an object of (something
8921 like) trivial or standard layout type with a non-deleted assignment
8922 and copy ctor. Detects const correctness violations, corrupting
8923 references, virtual table pointers, and bypassing non-trivial
8927 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8928 const vec
<tree
, va_gc
> *args
)
8930 /* Except for bcopy where it's second, the destination pointer is
8931 the first argument for all functions handled here. Compute
8932 the index of the destination and source arguments. */
8933 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8934 unsigned srcidx
= !dstidx
;
8936 tree dest
= (*args
)[dstidx
];
8937 if (!TREE_TYPE (dest
)
8938 || (TREE_CODE (TREE_TYPE (dest
)) != ARRAY_TYPE
8939 && !INDIRECT_TYPE_P (TREE_TYPE (dest
))))
8942 tree srctype
= NULL_TREE
;
8944 /* Determine the type of the pointed-to object and whether it's
8945 a complete class type. */
8946 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8948 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8951 /* Check to see if the raw memory call is made by a non-static member
8952 function with THIS as the destination argument for the destination
8953 type. If so, and if the class has no non-trivial bases or members,
8954 be more permissive. */
8955 if (current_function_decl
8956 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8957 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8959 tree ctx
= DECL_CONTEXT (current_function_decl
);
8960 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8961 tree binfo
= TYPE_BINFO (ctx
);
8964 && !BINFO_VTABLE (binfo
)
8965 && !first_non_trivial_field (desttype
))
8969 /* True if the class is trivial. */
8970 bool trivial
= trivial_type_p (desttype
);
8972 /* Set to true if DESTYPE has an accessible copy assignment. */
8973 bool hasassign
= false;
8974 /* True if all of the class' overloaded copy assignment operators
8975 are all trivial (and not deleted) and at least one of them is
8977 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8979 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8981 bool hasctors
[2] = { false, false };
8983 /* True if all of the class' overloaded copy constructors are all
8984 trivial (and not deleted) and at least one of them is accessible. */
8985 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8987 /* Set FLD to the first private/protected member of the class. */
8988 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8990 /* The warning format string. */
8991 const char *warnfmt
= NULL
;
8992 /* A suggested alternative to offer instead of the raw memory call.
8993 Empty string when none can be come up with. */
8994 const char *suggest
= "";
8995 bool warned
= false;
8997 switch (DECL_FUNCTION_CODE (fndecl
))
8999 case BUILT_IN_MEMSET
:
9000 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
9002 /* Diagnose setting non-copy-assignable or non-trivial types,
9003 or types with a private member, to (potentially) non-zero
9004 bytes. Since the value of the bytes being written is unknown,
9005 suggest using assignment instead (if one exists). Also warn
9006 for writes into objects for which zero-initialization doesn't
9007 mean all bits clear (pointer-to-member data, where null is all
9008 bits set). Since the value being written is (most likely)
9009 non-zero, simply suggest assignment (but not copy assignment). */
9010 suggest
= "; use assignment instead";
9012 warnfmt
= G_("%qD writing to an object of type %#qT with "
9013 "no trivial copy-assignment");
9015 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
9018 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
9019 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9020 "%qD writing to an object of type %#qT with "
9022 fndecl
, desttype
, access
, fld
);
9024 else if (!zero_init_p (desttype
))
9025 warnfmt
= G_("%qD writing to an object of type %#qT containing "
9026 "a pointer to data member%s");
9032 case BUILT_IN_BZERO
:
9033 /* Similarly to the above, diagnose clearing non-trivial or non-
9034 standard layout objects, or objects of types with no assignmenmt.
9035 Since the value being written is known to be zero, suggest either
9036 copy assignment, copy ctor, or default ctor as an alternative,
9037 depending on what's available. */
9039 if (hasassign
&& hasctors
[0])
9040 suggest
= G_("; use assignment or value-initialization instead");
9042 suggest
= G_("; use assignment instead");
9043 else if (hasctors
[0])
9044 suggest
= G_("; use value-initialization instead");
9047 warnfmt
= G_("%qD clearing an object of type %#qT with "
9048 "no trivial copy-assignment%s");
9050 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
9051 else if (!zero_init_p (desttype
))
9052 warnfmt
= G_("%qD clearing an object of type %#qT containing "
9053 "a pointer-to-member%s");
9056 case BUILT_IN_BCOPY
:
9057 case BUILT_IN_MEMCPY
:
9058 case BUILT_IN_MEMMOVE
:
9059 case BUILT_IN_MEMPCPY
:
9060 /* Determine the type of the source object. */
9061 srctype
= TREE_TYPE ((*args
)[srcidx
]);
9062 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
9063 srctype
= void_type_node
;
9065 srctype
= TREE_TYPE (srctype
);
9067 /* Since it's impossible to determine wheter the byte copy is
9068 being used in place of assignment to an existing object or
9069 as a substitute for initialization, assume it's the former.
9070 Determine the best alternative to use instead depending on
9071 what's not deleted. */
9072 if (hasassign
&& hasctors
[1])
9073 suggest
= G_("; use copy-assignment or copy-initialization instead");
9075 suggest
= G_("; use copy-assignment instead");
9076 else if (hasctors
[1])
9077 suggest
= G_("; use copy-initialization instead");
9080 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
9081 "copy-assignment%s");
9082 else if (!trivially_copyable_p (desttype
))
9083 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
9086 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
9089 && !VOID_TYPE_P (srctype
)
9090 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9091 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9094 /* Warn when copying into a non-trivial object from an object
9095 of a different type other than void or char. */
9096 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9097 "%qD copying an object of non-trivial type "
9098 "%#qT from an array of %#qT",
9099 fndecl
, desttype
, srctype
);
9102 && !VOID_TYPE_P (srctype
)
9103 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
9104 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
9107 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
9108 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9109 "%qD copying an object of type %#qT with "
9110 "%qs member %qD from an array of %#qT; use "
9111 "assignment or copy-initialization instead",
9112 fndecl
, desttype
, access
, fld
, srctype
);
9114 else if (!trivial
&& vec_safe_length (args
) > 2)
9116 tree sz
= maybe_constant_value ((*args
)[2]);
9117 if (!tree_fits_uhwi_p (sz
))
9120 /* Finally, warn on partial copies. */
9121 unsigned HOST_WIDE_INT typesize
9122 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
9123 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
9124 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9125 (typesize
- partial
> 1
9126 ? G_("%qD writing to an object of "
9127 "a non-trivial type %#qT leaves %wu "
9129 : G_("%qD writing to an object of "
9130 "a non-trivial type %#qT leaves %wu "
9132 fndecl
, desttype
, typesize
- partial
);
9136 case BUILT_IN_REALLOC
:
9138 if (!trivially_copyable_p (desttype
))
9139 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
9140 "%#qT; use %<new%> and %<delete%> instead");
9142 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
9143 "constructor; use %<new%> and %<delete%> instead");
9144 else if (!get_dtor (desttype
, tf_none
))
9145 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
9149 tree sz
= maybe_constant_value ((*args
)[1]);
9150 if (TREE_CODE (sz
) == INTEGER_CST
9151 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
9152 /* Finally, warn on reallocation into insufficient space. */
9153 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9154 "%qD moving an object of non-trivial type "
9155 "%#qT and size %E into a region of size %E",
9156 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
9168 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9169 warnfmt
, fndecl
, desttype
, suggest
);
9171 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
9172 warnfmt
, fndecl
, desttype
);
9176 inform (location_of (desttype
), "%#qT declared here", desttype
);
9179 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
9180 If FN is the result of resolving an overloaded target built-in,
9181 ORIG_FNDECL is the original function decl, otherwise it is null.
9182 This function performs no overload resolution, conversion, or other
9183 high-level operations. */
9186 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
9187 tsubst_flags_t complain
, tree orig_fndecl
)
9191 /* Remember roughly where this call is. */
9192 location_t loc
= cp_expr_loc_or_input_loc (fn
);
9193 fn
= build_call_a (fn
, nargs
, argarray
);
9194 SET_EXPR_LOCATION (fn
, loc
);
9196 fndecl
= get_callee_fndecl (fn
);
9198 orig_fndecl
= fndecl
;
9200 /* Check that arguments to builtin functions match the expectations. */
9202 && !processing_template_decl
9203 && fndecl_built_in_p (fndecl
))
9207 /* We need to take care that values to BUILT_IN_NORMAL
9209 for (i
= 0; i
< nargs
; i
++)
9210 argarray
[i
] = maybe_constant_value (argarray
[i
]);
9212 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
9213 orig_fndecl
, nargs
, argarray
))
9214 return error_mark_node
;
9217 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9220 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9221 function call is either the operand of a decltype-specifier or the
9222 right operand of a comma operator that is the operand of a
9223 decltype-specifier, a temporary object is not introduced for the
9224 prvalue. The type of the prvalue may be incomplete. */
9225 if (!(complain
& tf_decltype
))
9227 fn
= require_complete_type_sfinae (fn
, complain
);
9228 if (fn
== error_mark_node
)
9229 return error_mark_node
;
9231 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9233 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9234 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9237 return convert_from_reference (fn
);
9240 /* Returns the value to use for the in-charge parameter when making a
9241 call to a function with the indicated NAME.
9243 FIXME:Can't we find a neater way to do this mapping? */
9246 in_charge_arg_for_name (tree name
)
9248 if (IDENTIFIER_CTOR_P (name
))
9250 if (name
== complete_ctor_identifier
)
9251 return integer_one_node
;
9252 gcc_checking_assert (name
== base_ctor_identifier
);
9256 if (name
== complete_dtor_identifier
)
9257 return integer_two_node
;
9258 else if (name
== deleting_dtor_identifier
)
9259 return integer_three_node
;
9260 gcc_checking_assert (name
== base_dtor_identifier
);
9263 return integer_zero_node
;
9266 /* We've built up a constructor call RET. Complain if it delegates to the
9267 constructor we're currently compiling. */
9270 check_self_delegation (tree ret
)
9272 if (TREE_CODE (ret
) == TARGET_EXPR
)
9273 ret
= TARGET_EXPR_INITIAL (ret
);
9274 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9275 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9276 error ("constructor delegates to itself");
9279 /* Build a call to a constructor, destructor, or an assignment
9280 operator for INSTANCE, an expression with class type. NAME
9281 indicates the special member function to call; *ARGS are the
9282 arguments. ARGS may be NULL. This may change ARGS. BINFO
9283 indicates the base of INSTANCE that is to be passed as the `this'
9284 parameter to the member function called.
9286 FLAGS are the LOOKUP_* flags to use when processing the call.
9288 If NAME indicates a complete object constructor, INSTANCE may be
9289 NULL_TREE. In this case, the caller will call build_cplus_new to
9290 store the newly constructed object into a VAR_DECL. */
9293 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9294 tree binfo
, int flags
, tsubst_flags_t complain
)
9297 /* The type of the subobject to be constructed or destroyed. */
9299 vec
<tree
, va_gc
> *allocated
= NULL
;
9302 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9304 if (error_operand_p (instance
))
9305 return error_mark_node
;
9307 if (IDENTIFIER_DTOR_P (name
))
9309 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9310 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9311 /* Shortcut to avoid lazy destructor declaration. */
9312 return build_trivial_dtor_call (instance
);
9317 /* Resolve the name. */
9318 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9319 return error_mark_node
;
9321 binfo
= TYPE_BINFO (binfo
);
9324 gcc_assert (binfo
!= NULL_TREE
);
9326 class_type
= BINFO_TYPE (binfo
);
9328 /* Handle the special case where INSTANCE is NULL_TREE. */
9329 if (name
== complete_ctor_identifier
&& !instance
)
9330 instance
= build_dummy_object (class_type
);
9333 /* Convert to the base class, if necessary. */
9334 if (!same_type_ignoring_top_level_qualifiers_p
9335 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9337 if (IDENTIFIER_CDTOR_P (name
))
9338 /* For constructors and destructors, either the base is
9339 non-virtual, or it is virtual but we are doing the
9340 conversion from a constructor or destructor for the
9341 complete object. In either case, we can convert
9343 instance
= convert_to_base_statically (instance
, binfo
);
9346 /* However, for assignment operators, we must convert
9347 dynamically if the base is virtual. */
9348 gcc_checking_assert (name
== assign_op_identifier
);
9349 instance
= build_base_path (PLUS_EXPR
, instance
,
9350 binfo
, /*nonnull=*/1, complain
);
9355 gcc_assert (instance
!= NULL_TREE
);
9357 /* In C++17, "If the initializer expression is a prvalue and the
9358 cv-unqualified version of the source type is the same class as the class
9359 of the destination, the initializer expression is used to initialize the
9360 destination object." Handle that here to avoid doing overload
9362 if (cxx_dialect
>= cxx17
9363 && args
&& vec_safe_length (*args
) == 1
9364 && name
== complete_ctor_identifier
)
9366 tree arg
= (**args
)[0];
9368 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9369 && !TYPE_HAS_LIST_CTOR (class_type
)
9370 && CONSTRUCTOR_NELTS (arg
) == 1)
9371 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9373 if ((TREE_CODE (arg
) == TARGET_EXPR
9374 || TREE_CODE (arg
) == CONSTRUCTOR
)
9375 && (same_type_ignoring_top_level_qualifiers_p
9376 (class_type
, TREE_TYPE (arg
))))
9378 if (is_dummy_object (instance
))
9380 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9381 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9383 if ((complain
& tf_error
)
9384 && (flags
& LOOKUP_DELEGATING_CONS
))
9385 check_self_delegation (arg
);
9386 /* Avoid change of behavior on Wunused-var-2.C. */
9387 instance
= mark_lvalue_use (instance
);
9388 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9392 fns
= lookup_fnfields (binfo
, name
, 1);
9394 /* When making a call to a constructor or destructor for a subobject
9395 that uses virtual base classes, pass down a pointer to a VTT for
9397 if ((name
== base_ctor_identifier
9398 || name
== base_dtor_identifier
)
9399 && CLASSTYPE_VBASECLASSES (class_type
))
9404 /* If the current function is a complete object constructor
9405 or destructor, then we fetch the VTT directly.
9406 Otherwise, we look it up using the VTT we were given. */
9407 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9408 vtt
= decay_conversion (vtt
, complain
);
9409 if (vtt
== error_mark_node
)
9410 return error_mark_node
;
9411 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9412 if (BINFO_SUBVTT_INDEX (binfo
))
9413 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9419 allocated
= make_tree_vector ();
9423 vec_safe_insert (*args
, 0, sub_vtt
);
9426 ret
= build_new_method_call (instance
, fns
, args
,
9427 TYPE_BINFO (BINFO_TYPE (binfo
)),
9431 if (allocated
!= NULL
)
9432 release_tree_vector (allocated
);
9434 if ((complain
& tf_error
)
9435 && (flags
& LOOKUP_DELEGATING_CONS
)
9436 && name
== complete_ctor_identifier
)
9437 check_self_delegation (ret
);
9442 /* Return the NAME, as a C string. The NAME indicates a function that
9443 is a member of TYPE. *FREE_P is set to true if the caller must
9444 free the memory returned.
9446 Rather than go through all of this, we should simply set the names
9447 of constructors and destructors appropriately, and dispense with
9448 ctor_identifier, dtor_identifier, etc. */
9451 name_as_c_string (tree name
, tree type
, bool *free_p
)
9453 const char *pretty_name
;
9455 /* Assume that we will not allocate memory. */
9457 /* Constructors and destructors are special. */
9458 if (IDENTIFIER_CDTOR_P (name
))
9461 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9462 /* For a destructor, add the '~'. */
9463 if (IDENTIFIER_DTOR_P (name
))
9465 pretty_name
= concat ("~", pretty_name
, NULL
);
9466 /* Remember that we need to free the memory allocated. */
9470 else if (IDENTIFIER_CONV_OP_P (name
))
9472 pretty_name
= concat ("operator ",
9473 type_as_string_translate (TREE_TYPE (name
),
9474 TFF_PLAIN_IDENTIFIER
),
9476 /* Remember that we need to free the memory allocated. */
9480 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9482 return CONST_CAST (char *, pretty_name
);
9485 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9488 static z_candidate
*
9489 single_z_candidate (z_candidate
*candidates
)
9491 if (candidates
== NULL
)
9494 if (candidates
->next
)
9500 /* If CANDIDATE is invalid due to a bad argument type, return the
9501 pertinent conversion_info.
9503 Otherwise, return NULL. */
9505 static const conversion_info
*
9506 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9508 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9509 rejection_reason
*r
= candidate
->reason
;
9519 case rr_arg_conversion
:
9520 return &r
->u
.conversion
;
9522 case rr_bad_arg_conversion
:
9523 return &r
->u
.bad_conversion
;
9527 /* Issue an error and note complaining about a bad argument type at a
9528 callsite with a single candidate FNDECL.
9530 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9531 case input_location is used).
9532 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9533 the formal parameter. */
9536 complain_about_bad_argument (location_t arg_loc
,
9537 tree from_type
, tree to_type
,
9538 tree fndecl
, int parmnum
)
9540 auto_diagnostic_group d
;
9541 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9542 range_label
*label
= &rhs_label
;
9543 if (arg_loc
== UNKNOWN_LOCATION
)
9545 arg_loc
= input_location
;
9548 gcc_rich_location
richloc (arg_loc
, label
);
9550 "cannot convert %qH to %qI",
9551 from_type
, to_type
);
9552 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9556 /* Subroutine of build_new_method_call_1, for where there are no viable
9557 candidates for the call. */
9560 complain_about_no_candidates_for_method_call (tree instance
,
9561 z_candidate
*candidates
,
9562 tree explicit_targs
,
9564 tree optype
, tree name
,
9565 bool skip_first_for_error
,
9566 vec
<tree
, va_gc
> *user_args
)
9568 auto_diagnostic_group d
;
9569 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9570 cxx_incomplete_type_error (instance
, basetype
);
9572 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9573 basetype
, optype
, build_tree_list_vec (user_args
),
9574 TREE_TYPE (instance
));
9577 /* Special-case for when there's a single candidate that's failing
9578 due to a bad argument type. */
9579 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9580 if (const conversion_info
*conv
9581 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9583 complain_about_bad_argument (conv
->loc
,
9584 conv
->from
, conv
->to_type
,
9585 candidate
->fn
, conv
->n_arg
);
9589 tree arglist
= build_tree_list_vec (user_args
);
9590 tree errname
= name
;
9591 bool twiddle
= false;
9592 if (IDENTIFIER_CDTOR_P (errname
))
9594 twiddle
= IDENTIFIER_DTOR_P (errname
);
9595 errname
= constructor_name (basetype
);
9598 errname
= lookup_template_function (errname
, explicit_targs
);
9599 if (skip_first_for_error
)
9600 arglist
= TREE_CHAIN (arglist
);
9601 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9602 basetype
, &"~"[!twiddle
], errname
, arglist
,
9603 TREE_TYPE (instance
));
9605 print_z_candidates (location_of (name
), candidates
);
9608 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9609 be set, upon return, to the function called. ARGS may be NULL.
9610 This may change ARGS. */
9613 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9614 tree conversion_path
, int flags
,
9615 tree
*fn_p
, tsubst_flags_t complain
)
9617 struct z_candidate
*candidates
= 0, *cand
;
9618 tree explicit_targs
= NULL_TREE
;
9619 tree basetype
= NULL_TREE
;
9622 tree first_mem_arg
= NULL_TREE
;
9624 bool skip_first_for_error
;
9625 vec
<tree
, va_gc
> *user_args
;
9628 int template_only
= 0;
9632 vec
<tree
, va_gc
> *orig_args
= NULL
;
9635 gcc_assert (instance
!= NULL_TREE
);
9637 /* We don't know what function we're going to call, yet. */
9641 if (error_operand_p (instance
)
9642 || !fns
|| error_operand_p (fns
))
9643 return error_mark_node
;
9645 if (!BASELINK_P (fns
))
9647 if (complain
& tf_error
)
9648 error ("call to non-function %qD", fns
);
9649 return error_mark_node
;
9652 orig_instance
= instance
;
9655 /* Dismantle the baselink to collect all the information we need. */
9656 if (!conversion_path
)
9657 conversion_path
= BASELINK_BINFO (fns
);
9658 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9659 optype
= BASELINK_OPTYPE (fns
);
9660 fns
= BASELINK_FUNCTIONS (fns
);
9661 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9663 explicit_targs
= TREE_OPERAND (fns
, 1);
9664 fns
= TREE_OPERAND (fns
, 0);
9667 gcc_assert (OVL_P (fns
));
9668 fn
= OVL_FIRST (fns
);
9669 name
= DECL_NAME (fn
);
9671 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9672 gcc_assert (CLASS_TYPE_P (basetype
));
9674 user_args
= args
== NULL
? NULL
: *args
;
9675 /* Under DR 147 A::A() is an invalid constructor call,
9676 not a functional cast. */
9677 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9679 if (! (complain
& tf_error
))
9680 return error_mark_node
;
9682 basetype
= DECL_CONTEXT (fn
);
9683 name
= constructor_name (basetype
);
9684 auto_diagnostic_group d
;
9685 if (permerror (input_location
,
9686 "cannot call constructor %<%T::%D%> directly",
9688 inform (input_location
, "for a function-style cast, remove the "
9689 "redundant %<::%D%>", name
);
9690 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9695 if (processing_template_decl
)
9697 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9698 instance
= build_non_dependent_expr (instance
);
9700 make_args_non_dependent (*args
);
9703 /* Process the argument list. */
9704 if (args
!= NULL
&& *args
!= NULL
)
9706 *args
= resolve_args (*args
, complain
);
9708 return error_mark_node
;
9712 /* Consider the object argument to be used even if we end up selecting a
9713 static member function. */
9714 instance
= mark_type_use (instance
);
9716 /* Figure out whether to skip the first argument for the error
9717 message we will display to users if an error occurs. We don't
9718 want to display any compiler-generated arguments. The "this"
9719 pointer hasn't been added yet. However, we must remove the VTT
9720 pointer if this is a call to a base-class constructor or
9722 skip_first_for_error
= false;
9723 if (IDENTIFIER_CDTOR_P (name
))
9725 /* Callers should explicitly indicate whether they want to ctor
9726 the complete object or just the part without virtual bases. */
9727 gcc_assert (name
!= ctor_identifier
);
9729 /* Remove the VTT pointer, if present. */
9730 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9731 && CLASSTYPE_VBASECLASSES (basetype
))
9732 skip_first_for_error
= true;
9734 /* It's OK to call destructors and constructors on cv-qualified
9735 objects. Therefore, convert the INSTANCE to the unqualified
9736 type, if necessary. */
9737 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9739 instance
= build_this (instance
);
9740 instance
= build_nop (build_pointer_type (basetype
), instance
);
9741 instance
= build_fold_indirect_ref (instance
);
9745 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9747 /* For the overload resolution we need to find the actual `this`
9748 that would be captured if the call turns out to be to a
9749 non-static member function. Do not actually capture it at this
9751 if (DECL_CONSTRUCTOR_P (fn
))
9752 /* Constructors don't use the enclosing 'this'. */
9753 first_mem_arg
= instance
;
9755 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9757 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9758 p
= conversion_obstack_alloc (0);
9760 /* The number of arguments artificial parms in ARGS; we subtract one because
9761 there's no 'this' in ARGS. */
9762 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9764 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9765 initializer, not T({ }). */
9766 if (DECL_CONSTRUCTOR_P (fn
)
9767 && vec_safe_length (user_args
) > skip
9768 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9770 tree init_list
= (*user_args
)[skip
];
9771 tree init
= NULL_TREE
;
9773 gcc_assert (user_args
->length () == skip
+ 1
9774 && !(flags
& LOOKUP_ONLYCONVERTING
));
9776 /* If the initializer list has no elements and T is a class type with
9777 a default constructor, the object is value-initialized. Handle
9778 this here so we don't need to handle it wherever we use
9779 build_special_member_call. */
9780 if (CONSTRUCTOR_NELTS (init_list
) == 0
9781 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9782 /* For a user-provided default constructor, use the normal
9783 mechanisms so that protected access works. */
9784 && type_has_non_user_provided_default_constructor (basetype
)
9785 && !processing_template_decl
)
9786 init
= build_value_init (basetype
, complain
);
9788 /* If BASETYPE is an aggregate, we need to do aggregate
9790 else if (CP_AGGREGATE_TYPE_P (basetype
))
9792 init
= reshape_init (basetype
, init_list
, complain
);
9793 init
= digest_init (basetype
, init
, complain
);
9798 if (is_dummy_object (instance
))
9799 return get_target_expr_sfinae (init
, complain
);
9800 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9801 TREE_SIDE_EFFECTS (init
) = true;
9805 /* Otherwise go ahead with overload resolution. */
9806 add_list_candidates (fns
, first_mem_arg
, user_args
,
9807 basetype
, explicit_targs
, template_only
,
9808 conversion_path
, access_binfo
, flags
,
9809 &candidates
, complain
);
9812 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9813 explicit_targs
, template_only
, conversion_path
,
9814 access_binfo
, flags
, &candidates
, complain
);
9816 any_viable_p
= false;
9817 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9821 if (complain
& tf_error
)
9822 complain_about_no_candidates_for_method_call (instance
, candidates
,
9823 explicit_targs
, basetype
,
9825 skip_first_for_error
,
9827 call
= error_mark_node
;
9831 cand
= tourney (candidates
, complain
);
9838 if (complain
& tf_error
)
9840 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9841 arglist
= build_tree_list_vec (user_args
);
9842 if (skip_first_for_error
)
9843 arglist
= TREE_CHAIN (arglist
);
9844 auto_diagnostic_group d
;
9845 if (!any_strictly_viable (candidates
))
9846 error ("no matching function for call to %<%s(%A)%>",
9847 pretty_name
, arglist
);
9849 error ("call of overloaded %<%s(%A)%> is ambiguous",
9850 pretty_name
, arglist
);
9851 print_z_candidates (location_of (name
), candidates
);
9855 call
= error_mark_node
;
9862 if (!(flags
& LOOKUP_NONVIRTUAL
)
9863 && DECL_PURE_VIRTUAL_P (fn
)
9864 && instance
== current_class_ref
9865 && (complain
& tf_warning
))
9867 /* This is not an error, it is runtime undefined
9869 if (!current_function_decl
)
9870 warning (0, "pure virtual %q#D called from "
9871 "non-static data member initializer", fn
);
9872 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9873 || DECL_DESTRUCTOR_P (current_function_decl
))
9874 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9875 ? G_("pure virtual %q#D called from constructor")
9876 : G_("pure virtual %q#D called from destructor")),
9880 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9881 && !DECL_CONSTRUCTOR_P (fn
)
9882 && is_dummy_object (instance
))
9884 instance
= maybe_resolve_dummy (instance
, true);
9885 if (instance
== error_mark_node
)
9886 call
= error_mark_node
;
9887 else if (!is_dummy_object (instance
))
9889 /* We captured 'this' in the current lambda now that
9890 we know we really need it. */
9891 cand
->first_arg
= instance
;
9893 else if (any_dependent_bases_p ())
9894 /* We can't tell until instantiation time whether we can use
9895 *this as the implicit object argument. */;
9898 if (complain
& tf_error
)
9899 error ("cannot call member function %qD without object",
9901 call
= error_mark_node
;
9905 if (call
!= error_mark_node
)
9908 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9909 /* Now we know what function is being called. */
9912 /* Build the actual CALL_EXPR. */
9913 call
= build_over_call (cand
, flags
, complain
);
9914 /* In an expression of the form `a->f()' where `f' turns
9915 out to be a static member function, `a' is
9916 none-the-less evaluated. */
9917 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9918 && !is_dummy_object (instance
)
9919 && TREE_SIDE_EFFECTS (instance
))
9921 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9924 if (TREE_THIS_VOLATILE (a
))
9926 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9928 else if (call
!= error_mark_node
9929 && DECL_DESTRUCTOR_P (cand
->fn
)
9930 && !VOID_TYPE_P (TREE_TYPE (call
)))
9931 /* An explicit call of the form "x->~X()" has type
9932 "void". However, on platforms where destructors
9933 return "this" (i.e., those where
9934 targetm.cxx.cdtor_returns_this is true), such calls
9935 will appear to have a return value of pointer type
9936 to the low-level call machinery. We do not want to
9937 change the low-level machinery, since we want to be
9938 able to optimize "delete f()" on such platforms as
9939 "operator delete(~X(f()))" (rather than generating
9940 "t = f(), ~X(t), operator delete (t)"). */
9941 call
= build_nop (void_type_node
, call
);
9946 if (processing_template_decl
&& call
!= error_mark_node
)
9948 bool cast_to_void
= false;
9950 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9951 call
= TREE_OPERAND (call
, 1);
9952 else if (TREE_CODE (call
) == NOP_EXPR
)
9954 cast_to_void
= true;
9955 call
= TREE_OPERAND (call
, 0);
9957 if (INDIRECT_REF_P (call
))
9958 call
= TREE_OPERAND (call
, 0);
9959 call
= (build_min_non_dep_call_vec
9961 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9962 orig_instance
, orig_fns
, NULL_TREE
),
9964 SET_EXPR_LOCATION (call
, input_location
);
9965 call
= convert_from_reference (call
);
9967 call
= build_nop (void_type_node
, call
);
9970 /* Free all the conversions we allocated. */
9971 obstack_free (&conversion_obstack
, p
);
9973 if (orig_args
!= NULL
)
9974 release_tree_vector (orig_args
);
9979 /* Wrapper for above. */
9982 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9983 tree conversion_path
, int flags
,
9984 tree
*fn_p
, tsubst_flags_t complain
)
9987 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9988 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9990 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9994 /* Returns true iff standard conversion sequence ICS1 is a proper
9995 subsequence of ICS2. */
9998 is_subseq (conversion
*ics1
, conversion
*ics2
)
10000 /* We can assume that a conversion of the same code
10001 between the same types indicates a subsequence since we only get
10002 here if the types we are converting from are the same. */
10004 while (ics1
->kind
== ck_rvalue
10005 || ics1
->kind
== ck_lvalue
)
10006 ics1
= next_conversion (ics1
);
10010 while (ics2
->kind
== ck_rvalue
10011 || ics2
->kind
== ck_lvalue
)
10012 ics2
= next_conversion (ics2
);
10014 if (ics2
->kind
== ck_user
10015 || ics2
->kind
== ck_ambig
10016 || ics2
->kind
== ck_aggr
10017 || ics2
->kind
== ck_list
10018 || ics2
->kind
== ck_identity
)
10019 /* At this point, ICS1 cannot be a proper subsequence of
10020 ICS2. We can get a USER_CONV when we are comparing the
10021 second standard conversion sequence of two user conversion
10025 ics2
= next_conversion (ics2
);
10027 while (ics2
->kind
== ck_rvalue
10028 || ics2
->kind
== ck_lvalue
)
10029 ics2
= next_conversion (ics2
);
10031 if (ics2
->kind
== ics1
->kind
10032 && same_type_p (ics2
->type
, ics1
->type
)
10033 && (ics1
->kind
== ck_identity
10034 || same_type_p (next_conversion (ics2
)->type
,
10035 next_conversion (ics1
)->type
)))
10040 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
10041 be any _TYPE nodes. */
10044 is_properly_derived_from (tree derived
, tree base
)
10046 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
10049 /* We only allow proper derivation here. The DERIVED_FROM_P macro
10050 considers every class derived from itself. */
10051 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
10052 && DERIVED_FROM_P (base
, derived
));
10055 /* We build the ICS for an implicit object parameter as a pointer
10056 conversion sequence. However, such a sequence should be compared
10057 as if it were a reference conversion sequence. If ICS is the
10058 implicit conversion sequence for an implicit object parameter,
10059 modify it accordingly. */
10062 maybe_handle_implicit_object (conversion
**ics
)
10064 if ((*ics
)->this_p
)
10066 /* [over.match.funcs]
10068 For non-static member functions, the type of the
10069 implicit object parameter is "reference to cv X"
10070 where X is the class of which the function is a
10071 member and cv is the cv-qualification on the member
10072 function declaration. */
10073 conversion
*t
= *ics
;
10074 tree reference_type
;
10076 /* The `this' parameter is a pointer to a class type. Make the
10077 implicit conversion talk about a reference to that same class
10079 reference_type
= TREE_TYPE (t
->type
);
10080 reference_type
= build_reference_type (reference_type
);
10082 if (t
->kind
== ck_qual
)
10083 t
= next_conversion (t
);
10084 if (t
->kind
== ck_ptr
)
10085 t
= next_conversion (t
);
10086 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
10087 t
= direct_reference_binding (reference_type
, t
);
10089 t
->rvaluedness_matches_p
= 0;
10094 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
10095 and return the initial reference binding conversion. Otherwise,
10096 leave *ICS unchanged and return NULL. */
10098 static conversion
*
10099 maybe_handle_ref_bind (conversion
**ics
)
10101 if ((*ics
)->kind
== ck_ref_bind
)
10103 conversion
*old_ics
= *ics
;
10104 *ics
= next_conversion (old_ics
);
10105 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
10112 /* Get the expression at the beginning of the conversion chain C. */
10115 conv_get_original_expr (conversion
*c
)
10117 for (; c
; c
= next_conversion (c
))
10118 if (c
->kind
== ck_identity
|| c
->kind
== ck_ambig
)
10123 /* Return a tree representing the number of elements initialized by the
10124 list-initialization C. The caller must check that C converts to an
10128 nelts_initialized_by_list_init (conversion
*c
)
10130 /* If the array we're converting to has a dimension, we'll use that. */
10131 if (TYPE_DOMAIN (c
->type
))
10132 return array_type_nelts_top (c
->type
);
10135 /* Otherwise, we look at how many elements the constructor we're
10136 initializing from has. */
10137 tree ctor
= conv_get_original_expr (c
);
10138 return size_int (CONSTRUCTOR_NELTS (ctor
));
10142 /* True iff C is a conversion that binds a reference or a pointer to
10143 an array of unknown bound. */
10146 conv_binds_to_array_of_unknown_bound (conversion
*c
)
10148 /* ck_ref_bind won't have the reference stripped. */
10149 tree type
= non_reference (c
->type
);
10150 /* ck_qual won't have the pointer stripped. */
10151 type
= strip_pointer_operator (type
);
10152 return (TREE_CODE (type
) == ARRAY_TYPE
10153 && TYPE_DOMAIN (type
) == NULL_TREE
);
10156 /* Compare two implicit conversion sequences according to the rules set out in
10157 [over.ics.rank]. Return values:
10159 1: ics1 is better than ics2
10160 -1: ics2 is better than ics1
10161 0: ics1 and ics2 are indistinguishable */
10164 compare_ics (conversion
*ics1
, conversion
*ics2
)
10170 tree deref_from_type1
= NULL_TREE
;
10171 tree deref_from_type2
= NULL_TREE
;
10172 tree deref_to_type1
= NULL_TREE
;
10173 tree deref_to_type2
= NULL_TREE
;
10174 conversion_rank rank1
, rank2
;
10176 /* REF_BINDING is nonzero if the result of the conversion sequence
10177 is a reference type. In that case REF_CONV is the reference
10178 binding conversion. */
10179 conversion
*ref_conv1
;
10180 conversion
*ref_conv2
;
10182 /* Compare badness before stripping the reference conversion. */
10183 if (ics1
->bad_p
> ics2
->bad_p
)
10185 else if (ics1
->bad_p
< ics2
->bad_p
)
10188 /* Handle implicit object parameters. */
10189 maybe_handle_implicit_object (&ics1
);
10190 maybe_handle_implicit_object (&ics2
);
10192 /* Handle reference parameters. */
10193 ref_conv1
= maybe_handle_ref_bind (&ics1
);
10194 ref_conv2
= maybe_handle_ref_bind (&ics2
);
10196 /* List-initialization sequence L1 is a better conversion sequence than
10197 list-initialization sequence L2 if L1 converts to
10198 std::initializer_list<X> for some X and L2 does not. */
10199 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
10201 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
10206 When comparing the basic forms of implicit conversion sequences (as
10207 defined in _over.best.ics_)
10209 --a standard conversion sequence (_over.ics.scs_) is a better
10210 conversion sequence than a user-defined conversion sequence
10211 or an ellipsis conversion sequence, and
10213 --a user-defined conversion sequence (_over.ics.user_) is a
10214 better conversion sequence than an ellipsis conversion sequence
10215 (_over.ics.ellipsis_). */
10216 /* Use BAD_CONVERSION_RANK because we already checked for a badness
10217 mismatch. If both ICS are bad, we try to make a decision based on
10218 what would have happened if they'd been good. This is not an
10219 extension, we'll still give an error when we build up the call; this
10220 just helps us give a more helpful error message. */
10221 rank1
= BAD_CONVERSION_RANK (ics1
);
10222 rank2
= BAD_CONVERSION_RANK (ics2
);
10226 else if (rank1
< rank2
)
10229 if (ics1
->ellipsis_p
)
10230 /* Both conversions are ellipsis conversions. */
10233 /* User-defined conversion sequence U1 is a better conversion sequence
10234 than another user-defined conversion sequence U2 if they contain the
10235 same user-defined conversion operator or constructor and if the sec-
10236 ond standard conversion sequence of U1 is better than the second
10237 standard conversion sequence of U2. */
10239 /* Handle list-conversion with the same code even though it isn't always
10240 ranked as a user-defined conversion and it doesn't have a second
10241 standard conversion sequence; it will still have the desired effect.
10242 Specifically, we need to do the reference binding comparison at the
10243 end of this function. */
10245 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
10246 || ics1
->kind
== ck_aggr
|| ics2
->kind
== ck_aggr
)
10251 for (t1
= ics1
; t1
&& t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
10252 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
10253 || t1
->kind
== ck_list
)
10255 for (t2
= ics2
; t2
&& t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
10256 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
10257 || t2
->kind
== ck_list
)
10260 if (!t1
|| !t2
|| t1
->kind
!= t2
->kind
)
10262 else if (t1
->kind
== ck_user
)
10264 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10265 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10269 /* List-initialization sequence L1 is a better conversion sequence than
10270 list-initialization sequence L2 if
10272 -- L1 and L2 convert to arrays of the same element type, and either
10273 the number of elements n1 initialized by L1 is less than the number
10274 of elements n2 initialized by L2, or n1=n2 and L2 converts to an array
10275 of unknown bound and L1 does not. (Added in CWG 1307 and extended by
10277 else if (t1
->kind
== ck_aggr
10278 && TREE_CODE (t1
->type
) == ARRAY_TYPE
10279 && TREE_CODE (t2
->type
) == ARRAY_TYPE
)
10281 /* The type of the array elements must be the same. */
10282 if (!same_type_p (TREE_TYPE (t1
->type
), TREE_TYPE (t2
->type
)))
10285 tree n1
= nelts_initialized_by_list_init (t1
);
10286 tree n2
= nelts_initialized_by_list_init (t2
);
10287 if (tree_int_cst_lt (n1
, n2
))
10289 else if (tree_int_cst_lt (n2
, n1
))
10291 /* The n1 == n2 case. */
10292 bool c1
= conv_binds_to_array_of_unknown_bound (t1
);
10293 bool c2
= conv_binds_to_array_of_unknown_bound (t2
);
10296 else if (!c1
&& c2
)
10303 /* For ambiguous or aggregate conversions, use the target type as
10304 a proxy for the conversion function. */
10305 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10309 /* We can just fall through here, after setting up
10310 FROM_TYPE1 and FROM_TYPE2. */
10311 from_type1
= t1
->type
;
10312 from_type2
= t2
->type
;
10319 /* We're dealing with two standard conversion sequences.
10323 Standard conversion sequence S1 is a better conversion
10324 sequence than standard conversion sequence S2 if
10326 --S1 is a proper subsequence of S2 (comparing the conversion
10327 sequences in the canonical form defined by _over.ics.scs_,
10328 excluding any Lvalue Transformation; the identity
10329 conversion sequence is considered to be a subsequence of
10330 any non-identity conversion sequence */
10333 while (t1
->kind
!= ck_identity
)
10334 t1
= next_conversion (t1
);
10335 from_type1
= t1
->type
;
10338 while (t2
->kind
!= ck_identity
)
10339 t2
= next_conversion (t2
);
10340 from_type2
= t2
->type
;
10343 /* One sequence can only be a subsequence of the other if they start with
10344 the same type. They can start with different types when comparing the
10345 second standard conversion sequence in two user-defined conversion
10347 if (same_type_p (from_type1
, from_type2
))
10349 if (is_subseq (ics1
, ics2
))
10351 if (is_subseq (ics2
, ics1
))
10359 --the rank of S1 is better than the rank of S2 (by the rules
10362 Standard conversion sequences are ordered by their ranks: an Exact
10363 Match is a better conversion than a Promotion, which is a better
10364 conversion than a Conversion.
10366 Two conversion sequences with the same rank are indistinguishable
10367 unless one of the following rules applies:
10369 --A conversion that does not a convert a pointer, pointer to member,
10370 or std::nullptr_t to bool is better than one that does.
10372 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10373 so that we do not have to check it explicitly. */
10374 if (ics1
->rank
< ics2
->rank
)
10376 else if (ics2
->rank
< ics1
->rank
)
10379 to_type1
= ics1
->type
;
10380 to_type2
= ics2
->type
;
10382 /* A conversion from scalar arithmetic type to complex is worse than a
10383 conversion between scalar arithmetic types. */
10384 if (same_type_p (from_type1
, from_type2
)
10385 && ARITHMETIC_TYPE_P (from_type1
)
10386 && ARITHMETIC_TYPE_P (to_type1
)
10387 && ARITHMETIC_TYPE_P (to_type2
)
10388 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10389 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10391 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10397 if (TYPE_PTR_P (from_type1
)
10398 && TYPE_PTR_P (from_type2
)
10399 && TYPE_PTR_P (to_type1
)
10400 && TYPE_PTR_P (to_type2
))
10402 deref_from_type1
= TREE_TYPE (from_type1
);
10403 deref_from_type2
= TREE_TYPE (from_type2
);
10404 deref_to_type1
= TREE_TYPE (to_type1
);
10405 deref_to_type2
= TREE_TYPE (to_type2
);
10407 /* The rules for pointers to members A::* are just like the rules
10408 for pointers A*, except opposite: if B is derived from A then
10409 A::* converts to B::*, not vice versa. For that reason, we
10410 switch the from_ and to_ variables here. */
10411 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10412 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10413 || (TYPE_PTRMEMFUNC_P (from_type1
)
10414 && TYPE_PTRMEMFUNC_P (from_type2
)
10415 && TYPE_PTRMEMFUNC_P (to_type1
)
10416 && TYPE_PTRMEMFUNC_P (to_type2
)))
10418 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10419 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10420 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10421 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10424 if (deref_from_type1
!= NULL_TREE
10425 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10426 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10428 /* This was one of the pointer or pointer-like conversions.
10432 --If class B is derived directly or indirectly from class A,
10433 conversion of B* to A* is better than conversion of B* to
10434 void*, and conversion of A* to void* is better than
10435 conversion of B* to void*. */
10436 if (VOID_TYPE_P (deref_to_type1
)
10437 && VOID_TYPE_P (deref_to_type2
))
10439 if (is_properly_derived_from (deref_from_type1
,
10442 else if (is_properly_derived_from (deref_from_type2
,
10446 else if (VOID_TYPE_P (deref_to_type1
)
10447 || VOID_TYPE_P (deref_to_type2
))
10449 if (same_type_p (deref_from_type1
, deref_from_type2
))
10451 if (VOID_TYPE_P (deref_to_type2
))
10453 if (is_properly_derived_from (deref_from_type1
,
10457 /* We know that DEREF_TO_TYPE1 is `void' here. */
10458 else if (is_properly_derived_from (deref_from_type1
,
10463 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10464 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10468 --If class B is derived directly or indirectly from class A
10469 and class C is derived directly or indirectly from B,
10471 --conversion of C* to B* is better than conversion of C* to
10474 --conversion of B* to A* is better than conversion of C* to
10476 if (same_type_p (deref_from_type1
, deref_from_type2
))
10478 if (is_properly_derived_from (deref_to_type1
,
10481 else if (is_properly_derived_from (deref_to_type2
,
10485 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10487 if (is_properly_derived_from (deref_from_type2
,
10490 else if (is_properly_derived_from (deref_from_type1
,
10496 else if (CLASS_TYPE_P (non_reference (from_type1
))
10497 && same_type_p (from_type1
, from_type2
))
10499 tree from
= non_reference (from_type1
);
10503 --binding of an expression of type C to a reference of type
10504 B& is better than binding an expression of type C to a
10505 reference of type A&
10507 --conversion of C to B is better than conversion of C to A, */
10508 if (is_properly_derived_from (from
, to_type1
)
10509 && is_properly_derived_from (from
, to_type2
))
10511 if (is_properly_derived_from (to_type1
, to_type2
))
10513 else if (is_properly_derived_from (to_type2
, to_type1
))
10517 else if (CLASS_TYPE_P (non_reference (to_type1
))
10518 && same_type_p (to_type1
, to_type2
))
10520 tree to
= non_reference (to_type1
);
10524 --binding of an expression of type B to a reference of type
10525 A& is better than binding an expression of type C to a
10526 reference of type A&,
10528 --conversion of B to A is better than conversion of C to A */
10529 if (is_properly_derived_from (from_type1
, to
)
10530 && is_properly_derived_from (from_type2
, to
))
10532 if (is_properly_derived_from (from_type2
, from_type1
))
10534 else if (is_properly_derived_from (from_type1
, from_type2
))
10541 --S1 and S2 differ only in their qualification conversion and yield
10542 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10543 qualification signature of type T1 is a proper subset of the cv-
10544 qualification signature of type T2 */
10545 if (ics1
->kind
== ck_qual
10546 && ics2
->kind
== ck_qual
10547 && same_type_p (from_type1
, from_type2
))
10549 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10556 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10557 to an implicit object parameter of a non-static member function
10558 declared without a ref-qualifier, and either S1 binds an lvalue
10559 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10560 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10561 draft standard, 13.3.3.2)
10563 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10564 types to which the references refer are the same type except for
10565 top-level cv-qualifiers, and the type to which the reference
10566 initialized by S2 refers is more cv-qualified than the type to
10567 which the reference initialized by S1 refers.
10569 DR 1328 [over.match.best]: the context is an initialization by
10570 conversion function for direct reference binding (13.3.1.6) of a
10571 reference to function type, the return type of F1 is the same kind of
10572 reference (i.e. lvalue or rvalue) as the reference being initialized,
10573 and the return type of F2 is not. */
10575 if (ref_conv1
&& ref_conv2
)
10577 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10578 && (ref_conv1
->rvaluedness_matches_p
10579 != ref_conv2
->rvaluedness_matches_p
)
10580 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10581 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10582 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10584 if (ref_conv1
->bad_p
10585 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10586 TREE_TYPE (ref_conv2
->type
)))
10587 /* Don't prefer a bad conversion that drops cv-quals to a bad
10588 conversion with the wrong rvalueness. */
10590 return (ref_conv1
->rvaluedness_matches_p
10591 - ref_conv2
->rvaluedness_matches_p
);
10594 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10598 void f (int(&)[]), // (1)
10599 f (int(&)[1]), // (2)
10602 (2) is better than (1), but (3) should be equal to (1) and to
10603 (2). For that reason we don't use ck_qual for (1) which would
10604 give it the cr_exact rank while (3) remains ck_identity.
10605 Therefore we compare (1) and (2) here. For (1) we'll have
10607 ck_ref_bind <- ck_identity
10610 so to handle this we must look at ref_conv. */
10611 bool c1
= conv_binds_to_array_of_unknown_bound (ref_conv1
);
10612 bool c2
= conv_binds_to_array_of_unknown_bound (ref_conv2
);
10615 else if (!c1
&& c2
)
10618 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10619 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10620 if (ref_conv1
->bad_p
)
10622 /* Prefer the one that drops fewer cv-quals. */
10623 tree ftype
= next_conversion (ref_conv1
)->type
;
10624 int fquals
= cp_type_quals (ftype
);
10628 return comp_cv_qualification (q2
, q1
);
10635 -- A conversion that promotes an enumeration whose underlying type
10636 is fixed to its underlying type is better than one that promotes to
10637 the promoted underlying type, if the two are different. */
10638 if (ics1
->rank
== cr_promotion
10639 && ics2
->rank
== cr_promotion
10640 && UNSCOPED_ENUM_P (from_type1
)
10641 && ENUM_FIXED_UNDERLYING_TYPE_P (from_type1
)
10642 && same_type_p (from_type1
, from_type2
))
10644 tree utype
= ENUM_UNDERLYING_TYPE (from_type1
);
10645 tree prom
= type_promotes_to (from_type1
);
10646 if (!same_type_p (utype
, prom
))
10648 if (same_type_p (to_type1
, utype
)
10649 && same_type_p (to_type2
, prom
))
10651 else if (same_type_p (to_type2
, utype
)
10652 && same_type_p (to_type1
, prom
))
10657 /* Neither conversion sequence is better than the other. */
10661 /* The source type for this standard conversion sequence. */
10664 source_type (conversion
*t
)
10666 for (;; t
= next_conversion (t
))
10668 if (t
->kind
== ck_user
10669 || t
->kind
== ck_ambig
10670 || t
->kind
== ck_identity
)
10673 gcc_unreachable ();
10676 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10677 a pointer to LOSER and re-running joust to produce the warning if WINNER
10678 is actually used. */
10681 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10683 candidate_warning
*cw
= (candidate_warning
*)
10684 conversion_obstack_alloc (sizeof (candidate_warning
));
10686 cw
->next
= winner
->warnings
;
10687 winner
->warnings
= cw
;
10690 /* CAND is a constructor candidate in joust in C++17 and up. If it copies a
10691 prvalue returned from a conversion function, replace CAND with the candidate
10692 for the conversion and return true. Otherwise, return false. */
10695 joust_maybe_elide_copy (z_candidate
*&cand
)
10697 tree fn
= cand
->fn
;
10698 if (!DECL_COPY_CONSTRUCTOR_P (fn
) && !DECL_MOVE_CONSTRUCTOR_P (fn
))
10700 conversion
*conv
= cand
->convs
[0];
10701 gcc_checking_assert (conv
->kind
== ck_ref_bind
);
10702 conv
= next_conversion (conv
);
10703 if (conv
->kind
== ck_user
&& !TYPE_REF_P (conv
->type
))
10705 gcc_checking_assert (same_type_ignoring_top_level_qualifiers_p
10706 (conv
->type
, DECL_CONTEXT (fn
)));
10707 z_candidate
*uc
= conv
->cand
;
10708 if (DECL_CONV_FN_P (uc
->fn
))
10717 /* Compare two candidates for overloading as described in
10718 [over.match.best]. Return values:
10720 1: cand1 is better than cand2
10721 -1: cand2 is better than cand1
10722 0: cand1 and cand2 are indistinguishable */
10725 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10726 tsubst_flags_t complain
)
10729 int off1
= 0, off2
= 0;
10733 /* Candidates that involve bad conversions are always worse than those
10735 if (cand1
->viable
> cand2
->viable
)
10737 if (cand1
->viable
< cand2
->viable
)
10740 /* If we have two pseudo-candidates for conversions to the same type,
10741 or two candidates for the same function, arbitrarily pick one. */
10742 if (cand1
->fn
== cand2
->fn
10743 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10746 /* Prefer a non-deleted function over an implicitly deleted move
10747 constructor or assignment operator. This differs slightly from the
10748 wording for issue 1402 (which says the move op is ignored by overload
10749 resolution), but this way produces better error messages. */
10750 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10751 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10752 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10754 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10755 && move_fn_p (cand1
->fn
))
10757 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10758 && move_fn_p (cand2
->fn
))
10762 /* a viable function F1
10763 is defined to be a better function than another viable function F2 if
10764 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10765 ICSi(F2), and then */
10767 /* for some argument j, ICSj(F1) is a better conversion sequence than
10770 /* For comparing static and non-static member functions, we ignore
10771 the implicit object parameter of the non-static function. The
10772 standard says to pretend that the static function has an object
10773 parm, but that won't work with operator overloading. */
10774 len
= cand1
->num_convs
;
10775 if (len
!= cand2
->num_convs
)
10777 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10778 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10780 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10781 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10782 /* We're comparing a near-match list constructor and a near-match
10783 non-list constructor. Just treat them as unordered. */
10786 gcc_assert (static_1
!= static_2
);
10797 /* Handle C++17 copy elision in [over.match.ctor] (direct-init) context. The
10798 standard currently says that only constructors are candidates, but if one
10799 copies a prvalue returned by a conversion function we want to treat the
10800 conversion as the candidate instead.
10802 Clang does something similar, as discussed at
10803 http://lists.isocpp.org/core/2017/10/3166.php
10804 http://lists.isocpp.org/core/2019/03/5721.php */
10805 int elided_tiebreaker
= 0;
10806 if (len
== 1 && cxx_dialect
>= cxx17
10807 && DECL_P (cand1
->fn
)
10808 && DECL_COMPLETE_CONSTRUCTOR_P (cand1
->fn
)
10809 && !(cand1
->flags
& LOOKUP_ONLYCONVERTING
))
10811 bool elided1
= joust_maybe_elide_copy (cand1
);
10812 bool elided2
= joust_maybe_elide_copy (cand2
);
10813 /* As a tiebreaker below we will prefer a constructor to a conversion
10814 operator exposed this way. */
10815 elided_tiebreaker
= elided2
- elided1
;
10818 for (i
= 0; i
< len
; ++i
)
10820 conversion
*t1
= cand1
->convs
[i
+ off1
];
10821 conversion
*t2
= cand2
->convs
[i
+ off2
];
10822 int comp
= compare_ics (t1
, t2
);
10826 if ((complain
& tf_warning
)
10828 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10829 == cr_std
+ cr_promotion
)
10830 && t1
->kind
== ck_std
10831 && t2
->kind
== ck_std
10832 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10833 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10834 && (TYPE_PRECISION (t1
->type
)
10835 == TYPE_PRECISION (t2
->type
))
10836 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10837 || (TREE_CODE (next_conversion (t1
)->type
)
10838 == ENUMERAL_TYPE
)))
10840 tree type
= next_conversion (t1
)->type
;
10842 struct z_candidate
*w
, *l
;
10844 type1
= t1
->type
, type2
= t2
->type
,
10845 w
= cand1
, l
= cand2
;
10847 type1
= t2
->type
, type2
= t1
->type
,
10848 w
= cand2
, l
= cand1
;
10852 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10853 type
, type1
, type2
);
10854 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10857 add_warning (w
, l
);
10860 if (winner
&& comp
!= winner
)
10869 /* warn about confusing overload resolution for user-defined conversions,
10870 either between a constructor and a conversion op, or between two
10872 if ((complain
& tf_warning
)
10873 && winner
&& warn_conversion
&& cand1
->second_conv
10874 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10875 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10877 struct z_candidate
*w
, *l
;
10878 bool give_warning
= false;
10881 w
= cand1
, l
= cand2
;
10883 w
= cand2
, l
= cand1
;
10885 /* We don't want to complain about `X::operator T1 ()'
10886 beating `X::operator T2 () const', when T2 is a no less
10887 cv-qualified version of T1. */
10888 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10889 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10891 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10892 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10894 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10899 if (!comp_ptr_ttypes (t
, f
))
10900 give_warning
= true;
10903 give_warning
= true;
10909 tree source
= source_type (w
->convs
[0]);
10910 if (INDIRECT_TYPE_P (source
))
10911 source
= TREE_TYPE (source
);
10912 auto_diagnostic_group d
;
10913 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10914 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10915 source
, w
->second_conv
->type
))
10917 inform (input_location
, " because conversion sequence "
10918 "for the argument is better");
10922 add_warning (w
, l
);
10928 /* Put this tiebreaker first, so that we don't try to look at second_conv of
10929 a constructor candidate that doesn't have one. */
10930 if (elided_tiebreaker
)
10931 return elided_tiebreaker
;
10933 /* DR 495 moved this tiebreaker above the template ones. */
10934 /* or, if not that,
10935 the context is an initialization by user-defined conversion (see
10936 _dcl.init_ and _over.match.user_) and the standard conversion
10937 sequence from the return type of F1 to the destination type (i.e.,
10938 the type of the entity being initialized) is a better conversion
10939 sequence than the standard conversion sequence from the return type
10940 of F2 to the destination type. */
10942 if (cand1
->second_conv
)
10944 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10949 /* or, if not that,
10950 F1 is a non-template function and F2 is a template function
10953 if (!cand1
->template_decl
&& cand2
->template_decl
)
10955 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10958 /* or, if not that,
10959 F1 and F2 are template functions and the function template for F1 is
10960 more specialized than the template for F2 according to the partial
10963 if (cand1
->template_decl
&& cand2
->template_decl
)
10965 winner
= more_specialized_fn
10966 (TI_TEMPLATE (cand1
->template_decl
),
10967 TI_TEMPLATE (cand2
->template_decl
),
10968 /* [temp.func.order]: The presence of unused ellipsis and default
10969 arguments has no effect on the partial ordering of function
10970 templates. add_function_candidate() will not have
10971 counted the "this" argument for constructors. */
10972 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10977 /* Concepts: ... or, if not that, F1 is more constrained than F2.
10979 FIXME: For function templates with no winner, this subsumption may
10980 be computed a separate time. This needs to be validated, and if
10981 so, the redundant check removed. */
10982 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10984 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10989 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10990 if (deduction_guide_p (cand1
->fn
))
10992 gcc_assert (deduction_guide_p (cand2
->fn
));
10993 /* We distinguish between candidates from an explicit deduction guide and
10994 candidates built from a constructor based on DECL_ARTIFICIAL. */
10995 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10996 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10998 return art2
- art1
;
11002 /* Prefer the special copy guide over a declared copy/move
11004 if (copy_guide_p (cand1
->fn
))
11006 if (copy_guide_p (cand2
->fn
))
11009 /* Prefer a candidate generated from a non-template constructor. */
11010 int tg1
= template_guide_p (cand1
->fn
);
11011 int tg2
= template_guide_p (cand2
->fn
);
11017 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
11018 for all arguments the corresponding parameters of F1 and F2 have the same
11019 type (CWG 2273/2277). */
11020 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
11021 && !DECL_CONV_FN_P (cand1
->fn
)
11022 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
11023 && !DECL_CONV_FN_P (cand2
->fn
))
11025 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
11026 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
11028 bool used1
= false;
11029 bool used2
= false;
11030 if (base1
== base2
)
11031 /* No difference. */;
11032 else if (DERIVED_FROM_P (base1
, base2
))
11034 else if (DERIVED_FROM_P (base2
, base1
))
11037 if (int diff
= used2
- used1
)
11039 for (i
= 0; i
< len
; ++i
)
11041 conversion
*t1
= cand1
->convs
[i
+ off1
];
11042 conversion
*t2
= cand2
->convs
[i
+ off2
];
11043 if (!same_type_p (t1
->type
, t2
->type
))
11051 /* Check whether we can discard a builtin candidate, either because we
11052 have two identical ones or matching builtin and non-builtin candidates.
11054 (Pedantically in the latter case the builtin which matched the user
11055 function should not be added to the overload set, but we spot it here.
11058 ... the builtin candidates include ...
11059 - do not have the same parameter type list as any non-template
11060 non-member candidate. */
11062 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
11064 for (i
= 0; i
< len
; ++i
)
11065 if (!same_type_p (cand1
->convs
[i
]->type
,
11066 cand2
->convs
[i
]->type
))
11068 if (i
== cand1
->num_convs
)
11070 if (cand1
->fn
== cand2
->fn
)
11071 /* Two built-in candidates; arbitrarily pick one. */
11073 else if (identifier_p (cand1
->fn
))
11074 /* cand1 is built-in; prefer cand2. */
11077 /* cand2 is built-in; prefer cand1. */
11082 /* For candidates of a multi-versioned function, make the version with
11083 the highest priority win. This version will be checked for dispatching
11084 first. If this version can be inlined into the caller, the front-end
11085 will simply make a direct call to this function. */
11087 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
11088 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
11089 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
11090 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
11092 tree f1
= TREE_TYPE (cand1
->fn
);
11093 tree f2
= TREE_TYPE (cand2
->fn
);
11094 tree p1
= TYPE_ARG_TYPES (f1
);
11095 tree p2
= TYPE_ARG_TYPES (f2
);
11097 /* Check if cand1->fn and cand2->fn are versions of the same function. It
11098 is possible that cand1->fn and cand2->fn are function versions but of
11099 different functions. Check types to see if they are versions of the same
11101 if (compparms (p1
, p2
)
11102 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
11104 /* Always make the version with the higher priority, more
11105 specialized, win. */
11106 gcc_assert (targetm
.compare_version_priority
);
11107 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
11114 /* If the two function declarations represent the same function (this can
11115 happen with declarations in multiple scopes and arg-dependent lookup),
11116 arbitrarily choose one. But first make sure the default args we're
11118 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
11119 && equal_functions (cand1
->fn
, cand2
->fn
))
11121 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
11122 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
11124 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
11126 for (i
= 0; i
< len
; ++i
)
11128 /* Don't crash if the fn is variadic. */
11131 parms1
= TREE_CHAIN (parms1
);
11132 parms2
= TREE_CHAIN (parms2
);
11136 parms1
= TREE_CHAIN (parms1
);
11138 parms2
= TREE_CHAIN (parms2
);
11140 for (; parms1
; ++i
)
11142 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
11143 TREE_PURPOSE (parms2
)))
11147 if (complain
& tf_error
)
11149 auto_diagnostic_group d
;
11150 if (permerror (input_location
,
11151 "default argument mismatch in "
11152 "overload resolution"))
11154 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
11155 " candidate 1: %q#F", cand1
->fn
);
11156 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
11157 " candidate 2: %q#F", cand2
->fn
);
11164 add_warning (cand1
, cand2
);
11167 parms1
= TREE_CHAIN (parms1
);
11168 parms2
= TREE_CHAIN (parms2
);
11176 /* Extension: If the worst conversion for one candidate is better than the
11177 worst conversion for the other, take the first. */
11178 if (!pedantic
&& (complain
& tf_warning_or_error
))
11180 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
11181 struct z_candidate
*w
= 0, *l
= 0;
11183 for (i
= 0; i
< len
; ++i
)
11185 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
11186 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
11187 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
11188 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
11191 winner
= 1, w
= cand1
, l
= cand2
;
11193 winner
= -1, w
= cand2
, l
= cand1
;
11196 /* Don't choose a deleted function over ambiguity. */
11197 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
11201 auto_diagnostic_group d
;
11202 if (pedwarn (input_location
, 0,
11203 "ISO C++ says that these are ambiguous, even "
11204 "though the worst conversion for the first is "
11205 "better than the worst conversion for the second:"))
11207 print_z_candidate (input_location
, N_("candidate 1:"), w
);
11208 print_z_candidate (input_location
, N_("candidate 2:"), l
);
11212 add_warning (w
, l
);
11217 gcc_assert (!winner
);
11221 /* Given a list of candidates for overloading, find the best one, if any.
11222 This algorithm has a worst case of O(2n) (winner is last), and a best
11223 case of O(n/2) (totally ambiguous); much better than a sorting
11226 static struct z_candidate
*
11227 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
11229 struct z_candidate
*champ
= candidates
, *challenger
;
11231 int champ_compared_to_predecessor
= 0;
11233 /* Walk through the list once, comparing each current champ to the next
11234 candidate, knocking out a candidate or two with each comparison. */
11236 for (challenger
= champ
->next
; challenger
; )
11238 fate
= joust (champ
, challenger
, 0, complain
);
11240 challenger
= challenger
->next
;
11245 champ
= challenger
->next
;
11248 champ_compared_to_predecessor
= 0;
11252 champ
= challenger
;
11253 champ_compared_to_predecessor
= 1;
11256 challenger
= champ
->next
;
11260 /* Make sure the champ is better than all the candidates it hasn't yet
11261 been compared to. */
11263 for (challenger
= candidates
;
11264 challenger
!= champ
11265 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
11266 challenger
= challenger
->next
)
11268 fate
= joust (champ
, challenger
, 0, complain
);
11276 /* Returns nonzero if things of type FROM can be converted to TO. */
11279 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
11281 tree arg
= NULL_TREE
;
11282 /* implicit_conversion only considers user-defined conversions
11283 if it has an expression for the call argument list. */
11284 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
11285 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
11286 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
11289 /* Returns nonzero if things of type FROM can be converted to TO with a
11290 standard conversion. */
11293 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
11295 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
11298 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
11301 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
11302 tsubst_flags_t complain
)
11308 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11309 p
= conversion_obstack_alloc (0);
11310 /* We want to discard any access checks done for this test,
11311 as we might not be in the appropriate access context and
11312 we'll do the check again when we actually perform the
11314 push_deferring_access_checks (dk_deferred
);
11316 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11318 ok_p
= (t
&& !t
->bad_p
);
11320 /* Discard the access checks now. */
11321 pop_deferring_access_checks ();
11322 /* Free all the conversions we allocated. */
11323 obstack_free (&conversion_obstack
, p
);
11328 /* Like can_convert_arg, but allows dubious conversions as well. */
11331 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
11332 tsubst_flags_t complain
)
11337 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11338 p
= conversion_obstack_alloc (0);
11339 /* Try to perform the conversion. */
11340 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
11342 /* Free all the conversions we allocated. */
11343 obstack_free (&conversion_obstack
, p
);
11348 /* Convert EXPR to TYPE. Return the converted expression.
11350 Note that we allow bad conversions here because by the time we get to
11351 this point we are committed to doing the conversion. If we end up
11352 doing a bad conversion, convert_like will complain. */
11355 perform_implicit_conversion_flags (tree type
, tree expr
,
11356 tsubst_flags_t complain
, int flags
)
11360 location_t loc
= cp_expr_loc_or_input_loc (expr
);
11362 if (TYPE_REF_P (type
))
11363 expr
= mark_lvalue_use (expr
);
11365 expr
= mark_rvalue_use (expr
);
11367 if (error_operand_p (expr
))
11368 return error_mark_node
;
11370 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11371 p
= conversion_obstack_alloc (0);
11373 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11374 /*c_cast_p=*/false,
11379 if (complain
& tf_error
)
11381 /* If expr has unknown type, then it is an overloaded function.
11382 Call instantiate_type to get good error messages. */
11383 if (TREE_TYPE (expr
) == unknown_type_node
)
11384 instantiate_type (type
, expr
, complain
);
11385 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
11386 /* We gave an error. */;
11389 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
11390 gcc_rich_location
rich_loc (loc
, &label
);
11391 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
11392 expr
, TREE_TYPE (expr
), type
);
11395 expr
= error_mark_node
;
11397 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11399 /* In a template, we are only concerned about determining the
11400 type of non-dependent expressions, so we do not have to
11401 perform the actual conversion. But for initializers, we
11402 need to be able to perform it at instantiation
11403 (or instantiate_non_dependent_expr) time. */
11404 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11405 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11406 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11407 if (flags
& LOOKUP_NO_NARROWING
)
11408 IMPLICIT_CONV_EXPR_BRACED_INIT (expr
) = true;
11411 expr
= convert_like (conv
, expr
, complain
);
11413 /* Free all the conversions we allocated. */
11414 obstack_free (&conversion_obstack
, p
);
11420 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11422 return perform_implicit_conversion_flags (type
, expr
, complain
,
11426 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11427 permitted. If the conversion is valid, the converted expression is
11428 returned. Otherwise, NULL_TREE is returned, except in the case
11429 that TYPE is a class type; in that case, an error is issued. If
11430 C_CAST_P is true, then this direct-initialization is taking
11431 place as part of a static_cast being attempted as part of a C-style
11435 perform_direct_initialization_if_possible (tree type
,
11438 tsubst_flags_t complain
)
11443 if (type
== error_mark_node
|| error_operand_p (expr
))
11444 return error_mark_node
;
11447 If the destination type is a (possibly cv-qualified) class type:
11449 -- If the initialization is direct-initialization ...,
11450 constructors are considered. ... If no constructor applies, or
11451 the overload resolution is ambiguous, the initialization is
11453 if (CLASS_TYPE_P (type
))
11455 releasing_vec
args (make_tree_vector_single (expr
));
11456 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11457 &args
, type
, LOOKUP_NORMAL
, complain
);
11458 return build_cplus_new (type
, expr
, complain
);
11461 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11462 p
= conversion_obstack_alloc (0);
11464 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11466 LOOKUP_NORMAL
, complain
);
11467 if (!conv
|| conv
->bad_p
)
11469 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11471 /* In a template, we are only concerned about determining the
11472 type of non-dependent expressions, so we do not have to
11473 perform the actual conversion. But for initializers, we
11474 need to be able to perform it at instantiation
11475 (or instantiate_non_dependent_expr) time. */
11476 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11477 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11480 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11481 /*issue_conversion_warnings=*/false,
11485 /* Free all the conversions we allocated. */
11486 obstack_free (&conversion_obstack
, p
);
11491 /* When initializing a reference that lasts longer than a full-expression,
11492 this special rule applies:
11496 The temporary to which the reference is bound or the temporary
11497 that is the complete object to which the reference is bound
11498 persists for the lifetime of the reference.
11500 The temporaries created during the evaluation of the expression
11501 initializing the reference, except the temporary to which the
11502 reference is bound, are destroyed at the end of the
11503 full-expression in which they are created.
11505 In that case, we store the converted expression into a new
11506 VAR_DECL in a new scope.
11508 However, we want to be careful not to create temporaries when
11509 they are not required. For example, given:
11512 struct D : public B {};
11516 there is no need to copy the return value from "f"; we can just
11517 extend its lifetime. Similarly, given:
11520 struct T { operator S(); };
11524 we can extend the lifetime of the return value of the conversion
11527 The next several functions are involved in this lifetime extension. */
11529 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11530 reference is being bound to a temporary. Create and return a new
11531 VAR_DECL with the indicated TYPE; this variable will store the value to
11532 which the reference is bound. */
11535 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11537 tree var
= create_temporary_var (type
);
11539 /* Register the variable. */
11541 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11543 /* Namespace-scope or local static; give it a mangled name. */
11545 /* If an initializer is visible to multiple translation units, those
11546 translation units must agree on the addresses of the
11547 temporaries. Therefore the temporaries must be given a consistent name
11548 and vague linkage. The mangled name of a temporary is the name of the
11549 non-temporary object in whose initializer they appear, prefixed with
11550 GR and suffixed with a sequence number mangled using the usual rules
11551 for a seq-id. Temporaries are numbered with a pre-order, depth-first,
11552 left-to-right walk of the complete initializer. */
11554 TREE_STATIC (var
) = TREE_STATIC (decl
);
11555 TREE_PUBLIC (var
) = TREE_PUBLIC (decl
);
11556 if (vague_linkage_p (decl
))
11557 comdat_linkage (var
);
11559 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11560 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11562 tree name
= mangle_ref_init_variable (decl
);
11563 DECL_NAME (var
) = name
;
11564 SET_DECL_ASSEMBLER_NAME (var
, name
);
11567 /* Create a new cleanup level if necessary. */
11568 maybe_push_cleanup_level (type
);
11570 return pushdecl (var
);
11573 /* EXPR is the initializer for a variable DECL of reference or
11574 std::initializer_list type. Create, push and return a new VAR_DECL
11575 for the initializer so that it will live as long as DECL. Any
11576 cleanup for the new variable is returned through CLEANUP, and the
11577 code to initialize the new variable is returned through INITP. */
11580 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11587 /* Create the temporary variable. */
11588 type
= TREE_TYPE (expr
);
11589 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11590 layout_decl (var
, 0);
11591 /* If the rvalue is the result of a function call it will be
11592 a TARGET_EXPR. If it is some other construct (such as a
11593 member access expression where the underlying object is
11594 itself the result of a function call), turn it into a
11595 TARGET_EXPR here. It is important that EXPR be a
11596 TARGET_EXPR below since otherwise the INIT_EXPR will
11597 attempt to make a bitwise copy of EXPR to initialize
11599 if (TREE_CODE (expr
) != TARGET_EXPR
)
11600 expr
= get_target_expr (expr
);
11602 if (TREE_CODE (decl
) == FIELD_DECL
11603 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11605 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11606 "until the constructor exits", decl
);
11607 TREE_NO_WARNING (decl
) = true;
11610 /* Recursively extend temps in this initializer. */
11611 TARGET_EXPR_INITIAL (expr
)
11612 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11614 /* Any reference temp has a non-trivial initializer. */
11615 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11617 /* If the initializer is constant, put it in DECL_INITIAL so we get
11618 static initialization and use in constant expressions. */
11619 init
= maybe_constant_init (expr
);
11620 /* As in store_init_value. */
11621 init
= cp_fully_fold (init
);
11622 if (TREE_CONSTANT (init
))
11624 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11626 /* 5.19 says that a constant expression can include an
11627 lvalue-rvalue conversion applied to "a glvalue of literal type
11628 that refers to a non-volatile temporary object initialized
11629 with a constant expression". Rather than try to communicate
11630 that this VAR_DECL is a temporary, just mark it constexpr. */
11631 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11632 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11633 TREE_CONSTANT (var
) = true;
11634 TREE_READONLY (var
) = true;
11636 DECL_INITIAL (var
) = init
;
11640 /* Create the INIT_EXPR that will initialize the temporary
11642 init
= split_nonconstant_init (var
, expr
);
11643 if (at_function_scope_p ())
11645 add_decl_expr (var
);
11647 if (TREE_STATIC (var
))
11648 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11651 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11653 vec_safe_push (*cleanups
, cleanup
);
11656 /* We must be careful to destroy the temporary only
11657 after its initialization has taken place. If the
11658 initialization throws an exception, then the
11659 destructor should not be run. We cannot simply
11660 transform INIT into something like:
11662 (INIT, ({ CLEANUP_STMT; }))
11664 because emit_local_var always treats the
11665 initializer as a full-expression. Thus, the
11666 destructor would run too early; it would run at the
11667 end of initializing the reference variable, rather
11668 than at the end of the block enclosing the
11669 reference variable.
11671 The solution is to pass back a cleanup expression
11672 which the caller is responsible for attaching to
11673 the statement tree. */
11677 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11678 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11680 if (CP_DECL_THREAD_LOCAL_P (var
))
11681 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11684 static_aggregates
= tree_cons (NULL_TREE
, var
,
11685 static_aggregates
);
11688 /* Check whether the dtor is callable. */
11689 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11691 /* Avoid -Wunused-variable warning (c++/38958). */
11692 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11694 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11700 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11701 initializing a variable of that TYPE. */
11704 initialize_reference (tree type
, tree expr
,
11705 int flags
, tsubst_flags_t complain
)
11709 location_t loc
= cp_expr_loc_or_input_loc (expr
);
11711 if (type
== error_mark_node
|| error_operand_p (expr
))
11712 return error_mark_node
;
11714 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11715 p
= conversion_obstack_alloc (0);
11717 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11719 if (!conv
|| conv
->bad_p
)
11721 if (complain
& tf_error
)
11724 convert_like (conv
, expr
, complain
);
11725 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11726 && !TYPE_REF_IS_RVALUE (type
)
11727 && !lvalue_p (expr
))
11728 error_at (loc
, "invalid initialization of non-const reference of "
11729 "type %qH from an rvalue of type %qI",
11730 type
, TREE_TYPE (expr
));
11732 error_at (loc
, "invalid initialization of reference of type "
11733 "%qH from expression of type %qI", type
,
11736 return error_mark_node
;
11739 if (conv
->kind
== ck_ref_bind
)
11740 /* Perform the conversion. */
11741 expr
= convert_like (conv
, expr
, complain
);
11742 else if (conv
->kind
== ck_ambig
)
11743 /* We gave an error in build_user_type_conversion_1. */
11744 expr
= error_mark_node
;
11746 gcc_unreachable ();
11748 /* Free all the conversions we allocated. */
11749 obstack_free (&conversion_obstack
, p
);
11754 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11755 which is bound either to a reference or a std::initializer_list. */
11758 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11763 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11765 TREE_OPERAND (sub
, 1)
11766 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11769 if (TREE_CODE (sub
) != ADDR_EXPR
)
11771 /* Deal with binding to a subobject. */
11772 for (p
= &TREE_OPERAND (sub
, 0);
11773 (TREE_CODE (*p
) == COMPONENT_REF
11774 || TREE_CODE (*p
) == ARRAY_REF
); )
11775 p
= &TREE_OPERAND (*p
, 0);
11776 if (TREE_CODE (*p
) == TARGET_EXPR
)
11778 tree subinit
= NULL_TREE
;
11779 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11780 recompute_tree_invariant_for_addr_expr (sub
);
11782 init
= fold_convert (TREE_TYPE (init
), sub
);
11784 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11789 /* INIT is part of the initializer for DECL. If there are any
11790 reference or initializer lists being initialized, extend their
11791 lifetime to match that of DECL. */
11794 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11796 tree type
= TREE_TYPE (init
);
11797 if (processing_template_decl
)
11799 if (TYPE_REF_P (type
))
11800 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11804 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11805 ctor
= TARGET_EXPR_INITIAL (ctor
);
11806 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11808 if (is_std_init_list (type
))
11810 /* The temporary array underlying a std::initializer_list
11811 is handled like a reference temporary. */
11812 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11813 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11814 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11819 constructor_elt
*p
;
11820 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11821 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11822 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11824 recompute_constructor_flags (ctor
);
11825 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11826 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11833 /* Returns true iff an initializer for TYPE could contain temporaries that
11834 need to be extended because they are bound to references or
11835 std::initializer_list. */
11838 type_has_extended_temps (tree type
)
11840 type
= strip_array_types (type
);
11841 if (TYPE_REF_P (type
))
11843 if (CLASS_TYPE_P (type
))
11845 if (is_std_init_list (type
))
11847 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11848 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11849 if (type_has_extended_temps (TREE_TYPE (f
)))
11855 /* Returns true iff TYPE is some variant of std::initializer_list. */
11858 is_std_init_list (tree type
)
11860 if (!TYPE_P (type
))
11862 if (cxx_dialect
== cxx98
)
11864 /* Look through typedefs. */
11865 type
= TYPE_MAIN_VARIANT (type
);
11866 return (CLASS_TYPE_P (type
)
11867 && CP_TYPE_CONTEXT (type
) == std_node
11868 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11871 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11872 will accept an argument list of a single std::initializer_list<T>. */
11875 is_list_ctor (tree decl
)
11877 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11880 if (!args
|| args
== void_list_node
)
11883 arg
= non_reference (TREE_VALUE (args
));
11884 if (!is_std_init_list (arg
))
11887 args
= TREE_CHAIN (args
);
11889 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11890 /* There are more non-defaulted parms. */
11896 #include "gt-cp-call.h"