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, true if the context is
98 copy-initialization. */
99 BOOL_BITFIELD need_temporary_p
: 1;
100 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
101 from a pointer-to-derived to pointer-to-base is being performed. */
102 BOOL_BITFIELD base_p
: 1;
103 /* If KIND is ck_ref_bind, true when either an lvalue reference is
104 being bound to an lvalue expression or an rvalue reference is
105 being bound to an rvalue expression. If KIND is ck_rvalue or ck_base,
106 true when we are treating an lvalue as an rvalue (12.8p33). If
107 ck_identity, we will be binding a reference directly or decaying to
109 BOOL_BITFIELD rvaluedness_matches_p
: 1;
110 BOOL_BITFIELD check_narrowing
: 1;
111 /* Whether check_narrowing should only check TREE_CONSTANTs; used
112 in build_converted_constant_expr. */
113 BOOL_BITFIELD check_narrowing_const_only
: 1;
114 /* The type of the expression resulting from the conversion. */
117 /* The next conversion in the chain. Since the conversions are
118 arranged from outermost to innermost, the NEXT conversion will
119 actually be performed before this conversion. This variant is
120 used only when KIND is neither ck_identity, ck_ambig nor
121 ck_list. Please use the next_conversion function instead
122 of using this field directly. */
124 /* The expression at the beginning of the conversion chain. This
125 variant is used only if KIND is ck_identity or ck_ambig. */
127 /* The array of conversions for an initializer_list, so this
128 variant is used only when KIN D is ck_list. */
131 /* The function candidate corresponding to this conversion
132 sequence. This field is only used if KIND is ck_user. */
133 struct z_candidate
*cand
;
136 #define CONVERSION_RANK(NODE) \
137 ((NODE)->bad_p ? cr_bad \
138 : (NODE)->ellipsis_p ? cr_ellipsis \
139 : (NODE)->user_conv_p ? cr_user \
142 #define BAD_CONVERSION_RANK(NODE) \
143 ((NODE)->ellipsis_p ? cr_ellipsis \
144 : (NODE)->user_conv_p ? cr_user \
147 static struct obstack conversion_obstack
;
148 static bool conversion_obstack_initialized
;
149 struct rejection_reason
;
151 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
152 static int equal_functions (tree
, tree
);
153 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
155 static int compare_ics (conversion
*, conversion
*);
156 static void maybe_warn_class_memaccess (location_t
, tree
,
157 const vec
<tree
, va_gc
> *);
158 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
159 #define convert_like(CONV, EXPR, COMPLAIN) \
160 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \
161 /*issue_conversion_warnings=*/true, \
162 /*c_cast_p=*/false, (COMPLAIN))
163 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
164 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \
165 /*issue_conversion_warnings=*/true, \
166 /*c_cast_p=*/false, (COMPLAIN))
167 static tree
convert_like_real (conversion
*, tree
, tree
, int, bool,
168 bool, tsubst_flags_t
);
169 static void op_error (const op_location_t
&, enum tree_code
, enum tree_code
,
170 tree
, tree
, tree
, bool);
171 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
173 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
174 static void print_z_candidates (location_t
, struct z_candidate
*);
175 static tree
build_this (tree
);
176 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
177 static bool any_strictly_viable (struct z_candidate
*);
178 static struct z_candidate
*add_template_candidate
179 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
180 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
181 static struct z_candidate
*add_template_candidate_real
182 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
183 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
184 static void add_builtin_candidates
185 (struct z_candidate
**, enum tree_code
, enum tree_code
,
186 tree
, tree
*, int, tsubst_flags_t
);
187 static void add_builtin_candidate
188 (struct z_candidate
**, enum tree_code
, enum tree_code
,
189 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
190 static bool is_complete (tree
);
191 static void build_builtin_candidate
192 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
193 int, tsubst_flags_t
);
194 static struct z_candidate
*add_conv_candidate
195 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
196 tree
, tsubst_flags_t
);
197 static struct z_candidate
*add_function_candidate
198 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
199 tree
, int, conversion
**, tsubst_flags_t
);
200 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
202 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
204 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
205 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
206 static conversion
*next_conversion (conversion
*);
207 static bool is_subseq (conversion
*, conversion
*);
208 static conversion
*maybe_handle_ref_bind (conversion
**);
209 static void maybe_handle_implicit_object (conversion
**);
210 static struct z_candidate
*add_candidate
211 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
212 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
213 static tree
source_type (conversion
*);
214 static void add_warning (struct z_candidate
*, struct z_candidate
*);
215 static bool reference_compatible_p (tree
, tree
);
216 static conversion
*direct_reference_binding (tree
, conversion
*);
217 static bool promoted_arithmetic_type_p (tree
);
218 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
219 static char *name_as_c_string (tree
, tree
, bool *);
220 static tree
prep_operand (tree
);
221 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
222 bool, tree
, tree
, int, struct z_candidate
**,
224 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
225 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
227 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
228 NAME can take many forms... */
231 check_dtor_name (tree basetype
, tree name
)
233 /* Just accept something we've already complained about. */
234 if (name
== error_mark_node
)
237 if (TREE_CODE (name
) == TYPE_DECL
)
238 name
= TREE_TYPE (name
);
239 else if (TYPE_P (name
))
241 else if (identifier_p (name
))
243 if ((MAYBE_CLASS_TYPE_P (basetype
)
244 || TREE_CODE (basetype
) == ENUMERAL_TYPE
)
245 && name
== constructor_name (basetype
))
248 name
= get_type_value (name
);
254 template <class T> struct S { ~S(); };
258 NAME will be a class template. */
259 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
263 if (!name
|| name
== error_mark_node
)
265 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
268 /* We want the address of a function or method. We avoid creating a
269 pointer-to-member function. */
272 build_addr_func (tree function
, tsubst_flags_t complain
)
274 tree type
= TREE_TYPE (function
);
276 /* We have to do these by hand to avoid real pointer to member
278 if (TREE_CODE (type
) == METHOD_TYPE
)
280 if (TREE_CODE (function
) == OFFSET_REF
)
282 tree object
= build_address (TREE_OPERAND (function
, 0));
283 return get_member_function_from_ptrfunc (&object
,
284 TREE_OPERAND (function
, 1),
287 function
= build_address (function
);
290 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
295 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
296 POINTER_TYPE to those. Note, pointer to member function types
297 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
298 two variants. build_call_a is the primitive taking an array of
299 arguments, while build_call_n is a wrapper that handles varargs. */
302 build_call_n (tree function
, int n
, ...)
305 return build_call_a (function
, 0, NULL
);
308 tree
*argarray
= XALLOCAVEC (tree
, n
);
313 for (i
= 0; i
< n
; i
++)
314 argarray
[i
] = va_arg (ap
, tree
);
316 return build_call_a (function
, n
, argarray
);
320 /* Update various flags in cfun and the call itself based on what is being
321 called. Split out of build_call_a so that bot_manip can use it too. */
324 set_flags_from_callee (tree call
)
326 /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */
327 tree decl
= cp_get_callee_fndecl_nofold (call
);
329 /* We check both the decl and the type; a function may be known not to
330 throw without being declared throw(). */
331 bool nothrow
= decl
&& TREE_NOTHROW (decl
);
332 tree callee
= cp_get_callee (call
);
334 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (callee
)));
335 else if (TREE_CODE (call
) == CALL_EXPR
336 && internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
339 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
340 cp_function_chain
->can_throw
= 1;
342 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
343 current_function_returns_abnormally
= 1;
345 TREE_NOTHROW (call
) = nothrow
;
349 build_call_a (tree function
, int n
, tree
*argarray
)
356 function
= build_addr_func (function
, tf_warning_or_error
);
358 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
359 fntype
= TREE_TYPE (TREE_TYPE (function
));
360 gcc_assert (TREE_CODE (fntype
) == FUNCTION_TYPE
361 || TREE_CODE (fntype
) == METHOD_TYPE
);
362 result_type
= TREE_TYPE (fntype
);
363 /* An rvalue has no cv-qualifiers. */
364 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
365 result_type
= cv_unqualified (result_type
);
367 function
= build_call_array_loc (input_location
,
368 result_type
, function
, n
, argarray
);
369 set_flags_from_callee (function
);
371 decl
= get_callee_fndecl (function
);
373 if (decl
&& !TREE_USED (decl
))
375 /* We invoke build_call directly for several library
376 functions. These may have been declared normally if
377 we're building libgcc, so we can't just check
379 gcc_assert (DECL_ARTIFICIAL (decl
)
380 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
385 require_complete_eh_spec_types (fntype
, decl
);
387 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
389 /* Don't pass empty class objects by value. This is useful
390 for tags in STL, which are used to control overload resolution.
391 We don't need to handle other cases of copying empty classes. */
392 if (!decl
|| !fndecl_built_in_p (decl
))
393 for (i
= 0; i
< n
; i
++)
395 tree arg
= CALL_EXPR_ARG (function
, i
);
396 if (is_empty_class (TREE_TYPE (arg
))
397 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
399 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
400 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
401 CALL_EXPR_ARG (function
, i
) = arg
;
408 /* New overloading code. */
412 struct candidate_warning
{
414 candidate_warning
*next
;
417 /* Information for providing diagnostics about why overloading failed. */
419 enum rejection_reason_code
{
422 rr_explicit_conversion
,
423 rr_template_conversion
,
425 rr_bad_arg_conversion
,
426 rr_template_unification
,
429 rr_constraint_failure
432 struct conversion_info
{
433 /* The index of the argument, 0-based. */
435 /* The actual argument or its type. */
437 /* The type of the parameter. */
439 /* The location of the argument. */
443 struct rejection_reason
{
444 enum rejection_reason_code code
;
446 /* Information about an arity mismatch. */
448 /* The expected number of arguments. */
450 /* The actual number of arguments in the call. */
452 /* Whether the call was a varargs call. */
455 /* Information about an argument conversion mismatch. */
456 struct conversion_info conversion
;
457 /* Same, but for bad argument conversions. */
458 struct conversion_info bad_conversion
;
459 /* Information about template unification failures. These are the
460 parameters passed to fn_type_unification. */
468 unification_kind_t strict
;
470 } template_unification
;
471 /* Information about template instantiation failures. These are the
472 parameters passed to instantiate_template. */
476 } template_instantiation
;
481 /* The FUNCTION_DECL that will be called if this candidate is
482 selected by overload resolution. */
484 /* If not NULL_TREE, the first argument to use when calling this
487 /* The rest of the arguments to use when calling this function. If
488 there are no further arguments this may be NULL or it may be an
490 const vec
<tree
, va_gc
> *args
;
491 /* The implicit conversion sequences for each of the arguments to
494 /* The number of implicit conversion sequences. */
496 /* If FN is a user-defined conversion, the standard conversion
497 sequence from the type returned by FN to the desired destination
499 conversion
*second_conv
;
500 struct rejection_reason
*reason
;
501 /* If FN is a member function, the binfo indicating the path used to
502 qualify the name of FN at the call site. This path is used to
503 determine whether or not FN is accessible if it is selected by
504 overload resolution. The DECL_CONTEXT of FN will always be a
505 (possibly improper) base of this binfo. */
507 /* If FN is a non-static member function, the binfo indicating the
508 subobject to which the `this' pointer should be converted if FN
509 is selected by overload resolution. The type pointed to by
510 the `this' pointer must correspond to the most derived class
511 indicated by the CONVERSION_PATH. */
512 tree conversion_path
;
515 candidate_warning
*warnings
;
519 /* The flags active in add_candidate. */
523 /* Returns true iff T is a null pointer constant in the sense of
527 null_ptr_cst_p (tree t
)
529 tree type
= TREE_TYPE (t
);
533 A null pointer constant is an integral constant expression
534 (_expr.const_) rvalue of integer type that evaluates to zero or
535 an rvalue of type std::nullptr_t. */
536 if (NULLPTR_TYPE_P (type
))
539 if (cxx_dialect
>= cxx11
)
541 STRIP_ANY_LOCATION_WRAPPER (t
);
543 /* Core issue 903 says only literal 0 is a null pointer constant. */
544 if (TREE_CODE (type
) == INTEGER_TYPE
545 && !char_type_p (type
)
546 && TREE_CODE (t
) == INTEGER_CST
548 && !TREE_OVERFLOW (t
))
551 else if (CP_INTEGRAL_TYPE_P (type
))
553 t
= fold_non_dependent_expr (t
, tf_none
);
555 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
562 /* Returns true iff T is a null member pointer value (4.11). */
565 null_member_pointer_value_p (tree t
)
567 tree type
= TREE_TYPE (t
);
570 else if (TYPE_PTRMEMFUNC_P (type
))
571 return (TREE_CODE (t
) == CONSTRUCTOR
572 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
573 else if (TYPE_PTRDATAMEM_P (type
))
574 return integer_all_onesp (t
);
579 /* Returns nonzero if PARMLIST consists of only default parms,
580 ellipsis, and/or undeduced parameter packs. */
583 sufficient_parms_p (const_tree parmlist
)
585 for (; parmlist
&& parmlist
!= void_list_node
;
586 parmlist
= TREE_CHAIN (parmlist
))
587 if (!TREE_PURPOSE (parmlist
)
588 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
593 /* Allocate N bytes of memory from the conversion obstack. The memory
594 is zeroed before being returned. */
597 conversion_obstack_alloc (size_t n
)
600 if (!conversion_obstack_initialized
)
602 gcc_obstack_init (&conversion_obstack
);
603 conversion_obstack_initialized
= true;
605 p
= obstack_alloc (&conversion_obstack
, n
);
610 /* Allocate rejection reasons. */
612 static struct rejection_reason
*
613 alloc_rejection (enum rejection_reason_code code
)
615 struct rejection_reason
*p
;
616 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
621 static struct rejection_reason
*
622 arity_rejection (tree first_arg
, int expected
, int actual
)
624 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
625 int adjust
= first_arg
!= NULL_TREE
;
626 r
->u
.arity
.expected
= expected
- adjust
;
627 r
->u
.arity
.actual
= actual
- adjust
;
631 static struct rejection_reason
*
632 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
635 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
636 int adjust
= first_arg
!= NULL_TREE
;
637 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
638 r
->u
.conversion
.from
= from
;
639 r
->u
.conversion
.to_type
= to
;
640 r
->u
.conversion
.loc
= loc
;
644 static struct rejection_reason
*
645 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
648 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
649 int adjust
= first_arg
!= NULL_TREE
;
650 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
651 r
->u
.bad_conversion
.from
= from
;
652 r
->u
.bad_conversion
.to_type
= to
;
653 r
->u
.bad_conversion
.loc
= loc
;
657 static struct rejection_reason
*
658 explicit_conversion_rejection (tree from
, tree to
)
660 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
661 r
->u
.conversion
.n_arg
= 0;
662 r
->u
.conversion
.from
= from
;
663 r
->u
.conversion
.to_type
= to
;
664 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
668 static struct rejection_reason
*
669 template_conversion_rejection (tree from
, tree to
)
671 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
672 r
->u
.conversion
.n_arg
= 0;
673 r
->u
.conversion
.from
= from
;
674 r
->u
.conversion
.to_type
= to
;
675 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
679 static struct rejection_reason
*
680 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
681 const tree
*args
, unsigned int nargs
,
682 tree return_type
, unification_kind_t strict
,
685 size_t args_n_bytes
= sizeof (*args
) * nargs
;
686 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
687 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
688 r
->u
.template_unification
.tmpl
= tmpl
;
689 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
690 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
691 /* Copy args to our own storage. */
692 memcpy (args1
, args
, args_n_bytes
);
693 r
->u
.template_unification
.args
= args1
;
694 r
->u
.template_unification
.nargs
= nargs
;
695 r
->u
.template_unification
.return_type
= return_type
;
696 r
->u
.template_unification
.strict
= strict
;
697 r
->u
.template_unification
.flags
= flags
;
701 static struct rejection_reason
*
702 template_unification_error_rejection (void)
704 return alloc_rejection (rr_template_unification
);
707 static struct rejection_reason
*
708 invalid_copy_with_fn_template_rejection (void)
710 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
714 static struct rejection_reason
*
715 inherited_ctor_rejection (void)
717 struct rejection_reason
*r
= alloc_rejection (rr_inherited_ctor
);
721 // Build a constraint failure record, saving information into the
722 // template_instantiation field of the rejection. If FN is not a template
723 // declaration, the TMPL member is the FN declaration and TARGS is empty.
725 static struct rejection_reason
*
726 constraint_failure (tree fn
)
728 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
729 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
731 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
732 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
736 r
->u
.template_instantiation
.tmpl
= fn
;
737 r
->u
.template_instantiation
.targs
= NULL_TREE
;
742 /* Dynamically allocate a conversion. */
745 alloc_conversion (conversion_kind kind
)
748 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
753 /* Make sure that all memory on the conversion obstack has been
757 validate_conversion_obstack (void)
759 if (conversion_obstack_initialized
)
760 gcc_assert ((obstack_next_free (&conversion_obstack
)
761 == obstack_base (&conversion_obstack
)));
764 /* Dynamically allocate an array of N conversions. */
767 alloc_conversions (size_t n
)
769 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
773 build_conv (conversion_kind code
, tree type
, conversion
*from
)
776 conversion_rank rank
= CONVERSION_RANK (from
);
778 /* Note that the caller is responsible for filling in t->cand for
779 user-defined conversions. */
780 t
= alloc_conversion (code
);
804 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
805 t
->bad_p
= from
->bad_p
;
810 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
811 specialization of std::initializer_list<T>, if such a conversion is
815 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
817 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
818 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
819 conversion
**subconvs
= alloc_conversions (len
);
824 /* Within a list-initialization we can have more user-defined
826 flags
&= ~LOOKUP_NO_CONVERSION
;
827 /* But no narrowing conversions. */
828 flags
|= LOOKUP_NO_NARROWING
;
830 /* Can't make an array of these types. */
831 if (TYPE_REF_P (elttype
)
832 || TREE_CODE (elttype
) == FUNCTION_TYPE
833 || VOID_TYPE_P (elttype
))
836 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
839 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
840 false, flags
, complain
);
847 t
= alloc_conversion (ck_list
);
849 t
->u
.list
= subconvs
;
852 for (i
= 0; i
< len
; ++i
)
854 conversion
*sub
= subconvs
[i
];
855 if (sub
->rank
> t
->rank
)
857 if (sub
->user_conv_p
)
858 t
->user_conv_p
= true;
866 /* Return the next conversion of the conversion chain (if applicable),
867 or NULL otherwise. Please use this function instead of directly
868 accessing fields of struct conversion. */
871 next_conversion (conversion
*conv
)
874 || conv
->kind
== ck_identity
875 || conv
->kind
== ck_ambig
876 || conv
->kind
== ck_list
)
881 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
882 is a valid aggregate initializer for array type ATYPE. */
885 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
888 tree elttype
= TREE_TYPE (atype
);
889 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
891 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
893 if (TREE_CODE (elttype
) == ARRAY_TYPE
894 && TREE_CODE (val
) == CONSTRUCTOR
)
895 ok
= can_convert_array (elttype
, val
, flags
, complain
);
897 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
905 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
906 aggregate class, if such a conversion is possible. */
909 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
911 unsigned HOST_WIDE_INT i
= 0;
913 tree field
= next_initializable_field (TYPE_FIELDS (type
));
914 tree empty_ctor
= NULL_TREE
;
916 /* We already called reshape_init in implicit_conversion. */
918 /* The conversions within the init-list aren't affected by the enclosing
919 context; they're always simple copy-initialization. */
920 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
922 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
924 tree ftype
= TREE_TYPE (field
);
928 if (i
< CONSTRUCTOR_NELTS (ctor
))
929 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
930 else if (DECL_INITIAL (field
))
931 val
= get_nsdmi (field
, /*ctor*/false, complain
);
932 else if (TYPE_REF_P (ftype
))
933 /* Value-initialization of reference is ill-formed. */
937 if (empty_ctor
== NULL_TREE
)
938 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
943 if (TREE_CODE (ftype
) == ARRAY_TYPE
944 && TREE_CODE (val
) == CONSTRUCTOR
)
945 ok
= can_convert_array (ftype
, val
, flags
, complain
);
947 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
953 if (TREE_CODE (type
) == UNION_TYPE
)
957 if (i
< CONSTRUCTOR_NELTS (ctor
))
960 c
= alloc_conversion (ck_aggr
);
963 c
->user_conv_p
= true;
964 c
->check_narrowing
= true;
969 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
970 array type, if such a conversion is possible. */
973 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
976 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
977 tree elttype
= TREE_TYPE (type
);
982 enum conversion_rank rank
= cr_exact
;
984 /* We might need to propagate the size from the element to the array. */
985 complete_type (type
);
987 if (TYPE_DOMAIN (type
)
988 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
990 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
995 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
997 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1000 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1001 false, flags
, complain
);
1005 if (sub
->rank
> rank
)
1007 if (sub
->user_conv_p
)
1013 c
= alloc_conversion (ck_aggr
);
1016 c
->user_conv_p
= user
;
1022 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1023 complex type, if such a conversion is possible. */
1026 build_complex_conv (tree type
, tree ctor
, int flags
,
1027 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
;
1041 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1043 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1046 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1047 false, flags
, complain
);
1051 if (sub
->rank
> rank
)
1053 if (sub
->user_conv_p
)
1059 c
= alloc_conversion (ck_aggr
);
1062 c
->user_conv_p
= user
;
1068 /* Build a representation of the identity conversion from EXPR to
1069 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1072 build_identity_conv (tree type
, tree expr
)
1076 c
= alloc_conversion (ck_identity
);
1083 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1084 were multiple user-defined conversions to accomplish the job.
1085 Build a conversion that indicates that ambiguity. */
1088 build_ambiguous_conv (tree type
, tree expr
)
1092 c
= alloc_conversion (ck_ambig
);
1100 strip_top_quals (tree t
)
1102 if (TREE_CODE (t
) == ARRAY_TYPE
)
1104 return cp_build_qualified_type (t
, 0);
1107 /* Returns the standard conversion path (see [conv]) from type FROM to type
1108 TO, if any. For proper handling of null pointer constants, you must
1109 also pass the expression EXPR to convert from. If C_CAST_P is true,
1110 this conversion is coming from a C-style cast. */
1113 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1114 int flags
, tsubst_flags_t complain
)
1116 enum tree_code fcode
, tcode
;
1118 bool fromref
= false;
1121 to
= non_reference (to
);
1122 if (TYPE_REF_P (from
))
1125 from
= TREE_TYPE (from
);
1128 to
= strip_top_quals (to
);
1129 from
= strip_top_quals (from
);
1131 if (expr
&& type_unknown_p (expr
))
1133 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1135 tsubst_flags_t tflags
= tf_conv
;
1136 expr
= instantiate_type (to
, expr
, tflags
);
1137 if (expr
== error_mark_node
)
1139 from
= TREE_TYPE (expr
);
1141 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1143 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1144 expr
= resolve_nondeduced_context (expr
, complain
);
1145 from
= TREE_TYPE (expr
);
1149 fcode
= TREE_CODE (from
);
1150 tcode
= TREE_CODE (to
);
1152 conv
= build_identity_conv (from
, expr
);
1153 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1155 from
= type_decays_to (from
);
1156 fcode
= TREE_CODE (from
);
1157 /* Tell convert_like_real that we're using the address. */
1158 conv
->rvaluedness_matches_p
= true;
1159 conv
= build_conv (ck_lvalue
, from
, conv
);
1161 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1162 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1163 express the copy constructor call required by copy-initialization. */
1164 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1169 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1172 from
= strip_top_quals (bitfield_type
);
1173 fcode
= TREE_CODE (from
);
1176 conv
= build_conv (ck_rvalue
, from
, conv
);
1177 if (flags
& LOOKUP_PREFER_RVALUE
)
1178 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1179 conv
->rvaluedness_matches_p
= true;
1182 /* Allow conversion between `__complex__' data types. */
1183 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1185 /* The standard conversion sequence to convert FROM to TO is
1186 the standard conversion sequence to perform componentwise
1188 conversion
*part_conv
= standard_conversion
1189 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1194 conv
= build_conv (part_conv
->kind
, to
, conv
);
1195 conv
->rank
= part_conv
->rank
;
1203 if (same_type_p (from
, to
))
1205 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1206 conv
->type
= qualified_to
;
1211 A null pointer constant can be converted to a pointer type; ... A
1212 null pointer constant of integral type can be converted to an
1213 rvalue of type std::nullptr_t. */
1214 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1215 || NULLPTR_TYPE_P (to
))
1216 && ((expr
&& null_ptr_cst_p (expr
))
1217 || NULLPTR_TYPE_P (from
)))
1218 conv
= build_conv (ck_std
, to
, conv
);
1219 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1220 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1222 /* For backwards brain damage compatibility, allow interconversion of
1223 pointers and integers with a pedwarn. */
1224 conv
= build_conv (ck_std
, to
, conv
);
1227 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1229 /* For backwards brain damage compatibility, allow interconversion of
1230 enums and integers with a pedwarn. */
1231 conv
= build_conv (ck_std
, to
, conv
);
1234 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1235 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1240 if (tcode
== POINTER_TYPE
)
1242 to_pointee
= TREE_TYPE (to
);
1243 from_pointee
= TREE_TYPE (from
);
1245 /* Since this is the target of a pointer, it can't have function
1246 qualifiers, so any TYPE_QUALS must be for attributes const or
1247 noreturn. Strip them. */
1248 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1249 && TYPE_QUALS (to_pointee
))
1250 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1251 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1252 && TYPE_QUALS (from_pointee
))
1253 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1257 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1258 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1261 if (tcode
== POINTER_TYPE
1262 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1265 else if (VOID_TYPE_P (to_pointee
)
1266 && !TYPE_PTRDATAMEM_P (from
)
1267 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1269 tree nfrom
= TREE_TYPE (from
);
1270 /* Don't try to apply restrict to void. */
1271 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1272 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1273 from
= build_pointer_type (from_pointee
);
1274 conv
= build_conv (ck_ptr
, from
, conv
);
1276 else if (TYPE_PTRDATAMEM_P (from
))
1278 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1279 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1281 if (same_type_p (fbase
, tbase
))
1282 /* No base conversion needed. */;
1283 else if (DERIVED_FROM_P (fbase
, tbase
)
1284 && (same_type_ignoring_top_level_qualifiers_p
1285 (from_pointee
, to_pointee
)))
1287 from
= build_ptrmem_type (tbase
, from_pointee
);
1288 conv
= build_conv (ck_pmem
, from
, conv
);
1293 else if (CLASS_TYPE_P (from_pointee
)
1294 && CLASS_TYPE_P (to_pointee
)
1297 An rvalue of type "pointer to cv D," where D is a
1298 class type, can be converted to an rvalue of type
1299 "pointer to cv B," where B is a base class (clause
1300 _class.derived_) of D. If B is an inaccessible
1301 (clause _class.access_) or ambiguous
1302 (_class.member.lookup_) base class of D, a program
1303 that necessitates this conversion is ill-formed.
1304 Therefore, we use DERIVED_FROM_P, and do not check
1305 access or uniqueness. */
1306 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1309 = cp_build_qualified_type (to_pointee
,
1310 cp_type_quals (from_pointee
));
1311 from
= build_pointer_type (from_pointee
);
1312 conv
= build_conv (ck_ptr
, from
, conv
);
1313 conv
->base_p
= true;
1316 if (same_type_p (from
, to
))
1318 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1319 /* In a C-style cast, we ignore CV-qualification because we
1320 are allowed to perform a static_cast followed by a
1322 conv
= build_conv (ck_qual
, to
, conv
);
1323 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1324 conv
= build_conv (ck_qual
, to
, conv
);
1325 else if (expr
&& string_conv_p (to
, expr
, 0))
1326 /* converting from string constant to char *. */
1327 conv
= build_conv (ck_qual
, to
, conv
);
1328 else if (fnptr_conv_p (to
, from
))
1329 conv
= build_conv (ck_fnptr
, to
, conv
);
1330 /* Allow conversions among compatible ObjC pointer types (base
1331 conversions have been already handled above). */
1332 else if (c_dialect_objc ()
1333 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1334 conv
= build_conv (ck_ptr
, to
, conv
);
1335 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1337 conv
= build_conv (ck_ptr
, to
, conv
);
1345 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1347 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1348 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1349 tree fbase
= class_of_this_parm (fromfn
);
1350 tree tbase
= class_of_this_parm (tofn
);
1352 if (!DERIVED_FROM_P (fbase
, tbase
))
1355 tree fstat
= static_fn_type (fromfn
);
1356 tree tstat
= static_fn_type (tofn
);
1357 if (same_type_p (tstat
, fstat
)
1358 || fnptr_conv_p (tstat
, fstat
))
1363 if (!same_type_p (fbase
, tbase
))
1365 from
= build_memfn_type (fstat
,
1367 cp_type_quals (tbase
),
1368 type_memfn_rqual (tofn
));
1369 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1370 conv
= build_conv (ck_pmem
, from
, conv
);
1371 conv
->base_p
= true;
1373 if (fnptr_conv_p (tstat
, fstat
))
1374 conv
= build_conv (ck_fnptr
, to
, conv
);
1376 else if (tcode
== BOOLEAN_TYPE
)
1380 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1381 to member type can be converted to a prvalue of type bool. ...
1382 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1383 std::nullptr_t can be converted to a prvalue of type bool; */
1384 if (ARITHMETIC_TYPE_P (from
)
1385 || UNSCOPED_ENUM_P (from
)
1386 || fcode
== POINTER_TYPE
1387 || TYPE_PTRMEM_P (from
)
1388 || NULLPTR_TYPE_P (from
))
1390 conv
= build_conv (ck_std
, to
, conv
);
1391 if (fcode
== POINTER_TYPE
1392 || TYPE_PTRDATAMEM_P (from
)
1393 || (TYPE_PTRMEMFUNC_P (from
)
1394 && conv
->rank
< cr_pbool
)
1395 || NULLPTR_TYPE_P (from
))
1396 conv
->rank
= cr_pbool
;
1397 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1399 if (flags
& LOOKUP_NO_NARROWING
)
1400 conv
->check_narrowing
= true;
1406 /* We don't check for ENUMERAL_TYPE here because there are no standard
1407 conversions to enum type. */
1408 /* As an extension, allow conversion to complex type. */
1409 else if (ARITHMETIC_TYPE_P (to
))
1411 if (! (INTEGRAL_CODE_P (fcode
)
1412 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1413 || SCOPED_ENUM_P (from
))
1415 conv
= build_conv (ck_std
, to
, conv
);
1417 /* Give this a better rank if it's a promotion. */
1418 if (same_type_p (to
, type_promotes_to (from
))
1419 && next_conversion (conv
)->rank
<= cr_promotion
)
1420 conv
->rank
= cr_promotion
;
1422 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1423 && vector_types_convertible_p (from
, to
, false))
1424 return build_conv (ck_std
, to
, conv
);
1425 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1426 && is_properly_derived_from (from
, to
))
1428 if (conv
->kind
== ck_rvalue
)
1429 conv
= next_conversion (conv
);
1430 conv
= build_conv (ck_base
, to
, conv
);
1431 /* The derived-to-base conversion indicates the initialization
1432 of a parameter with base type from an object of a derived
1433 type. A temporary object is created to hold the result of
1434 the conversion unless we're binding directly to a reference. */
1435 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1436 if (flags
& LOOKUP_PREFER_RVALUE
)
1437 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1438 conv
->rvaluedness_matches_p
= true;
1443 if (flags
& LOOKUP_NO_NARROWING
)
1444 conv
->check_narrowing
= true;
1449 /* Returns nonzero if T1 is reference-related to T2. */
1452 reference_related_p (tree t1
, tree t2
)
1454 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1457 t1
= TYPE_MAIN_VARIANT (t1
);
1458 t2
= TYPE_MAIN_VARIANT (t2
);
1462 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1463 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1465 return (same_type_p (t1
, t2
)
1466 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1467 && DERIVED_FROM_P (t1
, t2
)));
1470 /* Returns nonzero if T1 is reference-compatible with T2. */
1473 reference_compatible_p (tree t1
, tree t2
)
1477 "cv1 T1" is reference compatible with "cv2 T2" if
1478 * T1 is reference-related to T2 or
1479 * T2 is "noexcept function" and T1 is "function", where the
1480 function types are otherwise the same,
1481 and cv1 is the same cv-qualification as, or greater cv-qualification
1483 return ((reference_related_p (t1
, t2
)
1484 || fnptr_conv_p (t1
, t2
))
1485 && at_least_as_qualified_p (t1
, t2
));
1488 /* A reference of the indicated TYPE is being bound directly to the
1489 expression represented by the implicit conversion sequence CONV.
1490 Return a conversion sequence for this binding. */
1493 direct_reference_binding (tree type
, conversion
*conv
)
1497 gcc_assert (TYPE_REF_P (type
));
1498 gcc_assert (!TYPE_REF_P (conv
->type
));
1500 t
= TREE_TYPE (type
);
1502 if (conv
->kind
== ck_identity
)
1503 /* Mark the identity conv as to not decay to rvalue. */
1504 conv
->rvaluedness_matches_p
= true;
1508 When a parameter of reference type binds directly
1509 (_dcl.init.ref_) to an argument expression, the implicit
1510 conversion sequence is the identity conversion, unless the
1511 argument expression has a type that is a derived class of the
1512 parameter type, in which case the implicit conversion sequence is
1513 a derived-to-base Conversion.
1515 If the parameter binds directly to the result of applying a
1516 conversion function to the argument expression, the implicit
1517 conversion sequence is a user-defined conversion sequence
1518 (_over.ics.user_), with the second standard conversion sequence
1519 either an identity conversion or, if the conversion function
1520 returns an entity of a type that is a derived class of the
1521 parameter type, a derived-to-base conversion. */
1522 if (is_properly_derived_from (conv
->type
, t
))
1524 /* Represent the derived-to-base conversion. */
1525 conv
= build_conv (ck_base
, t
, conv
);
1526 /* We will actually be binding to the base-class subobject in
1527 the derived class, so we mark this conversion appropriately.
1528 That way, convert_like knows not to generate a temporary. */
1529 conv
->need_temporary_p
= false;
1532 return build_conv (ck_ref_bind
, type
, conv
);
1535 /* Returns the conversion path from type FROM to reference type TO for
1536 purposes of reference binding. For lvalue binding, either pass a
1537 reference type to FROM or an lvalue expression to EXPR. If the
1538 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1539 the conversion returned. If C_CAST_P is true, this
1540 conversion is coming from a C-style cast. */
1543 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1544 tsubst_flags_t complain
)
1546 conversion
*conv
= NULL
;
1547 tree to
= TREE_TYPE (rto
);
1552 cp_lvalue_kind gl_kind
;
1555 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1557 expr
= instantiate_type (to
, expr
, tf_none
);
1558 if (expr
== error_mark_node
)
1560 from
= TREE_TYPE (expr
);
1563 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1565 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1566 /* DR 1288: Otherwise, if the initializer list has a single element
1567 of type E and ... [T's] referenced type is reference-related to E,
1568 the object or reference is initialized from that element... */
1569 if (CONSTRUCTOR_NELTS (expr
) == 1)
1571 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1572 if (error_operand_p (elt
))
1574 tree etype
= TREE_TYPE (elt
);
1575 if (reference_related_p (to
, etype
))
1582 /* Otherwise, if T is a reference type, a prvalue temporary of the type
1583 referenced by T is copy-list-initialized, and the reference is bound
1584 to that temporary. */
1585 CONSTRUCTOR_IS_DIRECT_INIT (expr
) = false;
1589 if (TYPE_REF_P (from
))
1591 from
= TREE_TYPE (from
);
1592 if (!TYPE_REF_IS_RVALUE (rfrom
)
1593 || TREE_CODE (from
) == FUNCTION_TYPE
)
1594 gl_kind
= clk_ordinary
;
1596 gl_kind
= clk_rvalueref
;
1599 gl_kind
= lvalue_kind (expr
);
1600 else if (CLASS_TYPE_P (from
)
1601 || TREE_CODE (from
) == ARRAY_TYPE
)
1602 gl_kind
= clk_class
;
1606 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1607 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1608 && (gl_kind
& clk_class
))
1611 /* Same mask as real_lvalue_p. */
1612 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1615 if ((gl_kind
& clk_bitfield
) != 0)
1616 tfrom
= unlowered_expr_type (expr
);
1618 /* Figure out whether or not the types are reference-related and
1619 reference compatible. We have to do this after stripping
1620 references from FROM. */
1621 related_p
= reference_related_p (to
, tfrom
);
1622 /* If this is a C cast, first convert to an appropriately qualified
1623 type, so that we can later do a const_cast to the desired type. */
1624 if (related_p
&& c_cast_p
1625 && !at_least_as_qualified_p (to
, tfrom
))
1626 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1627 compatible_p
= reference_compatible_p (to
, tfrom
);
1629 /* Directly bind reference when target expression's type is compatible with
1630 the reference and expression is an lvalue. In DR391, the wording in
1631 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1632 const and rvalue references to rvalues of compatible class type.
1633 We should also do direct bindings for non-class xvalues. */
1634 if ((related_p
|| compatible_p
) && gl_kind
)
1638 If the initializer expression
1640 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1641 is reference-compatible with "cv2 T2,"
1643 the reference is bound directly to the initializer expression
1647 If the initializer expression is an rvalue, with T2 a class type,
1648 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1649 is bound to the object represented by the rvalue or to a sub-object
1650 within that object. */
1652 conv
= build_identity_conv (tfrom
, expr
);
1653 conv
= direct_reference_binding (rto
, conv
);
1655 if (TYPE_REF_P (rfrom
))
1656 /* Handle rvalue reference to function properly. */
1657 conv
->rvaluedness_matches_p
1658 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1660 conv
->rvaluedness_matches_p
1661 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1663 if ((gl_kind
& clk_bitfield
) != 0
1664 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1665 /* For the purposes of overload resolution, we ignore the fact
1666 this expression is a bitfield or packed field. (In particular,
1667 [over.ics.ref] says specifically that a function with a
1668 non-const reference parameter is viable even if the
1669 argument is a bitfield.)
1671 However, when we actually call the function we must create
1672 a temporary to which to bind the reference. If the
1673 reference is volatile, or isn't const, then we cannot make
1674 a temporary, so we just issue an error when the conversion
1676 conv
->need_temporary_p
= true;
1678 /* Don't allow binding of lvalues (other than function lvalues) to
1679 rvalue references. */
1680 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1681 && TREE_CODE (to
) != FUNCTION_TYPE
)
1684 /* Nor the reverse. */
1685 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1686 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1687 || (flags
& LOOKUP_NO_RVAL_BIND
))
1688 && TREE_CODE (to
) != FUNCTION_TYPE
)
1696 /* [class.conv.fct] A conversion function is never used to convert a
1697 (possibly cv-qualified) object to the (possibly cv-qualified) same
1698 object type (or a reference to it), to a (possibly cv-qualified) base
1699 class of that type (or a reference to it).... */
1700 else if (CLASS_TYPE_P (from
) && !related_p
1701 && !(flags
& LOOKUP_NO_CONVERSION
))
1705 If the initializer expression
1707 -- has a class type (i.e., T2 is a class type) can be
1708 implicitly converted to an lvalue of type "cv3 T3," where
1709 "cv1 T1" is reference-compatible with "cv3 T3". (this
1710 conversion is selected by enumerating the applicable
1711 conversion functions (_over.match.ref_) and choosing the
1712 best one through overload resolution. (_over.match_).
1714 the reference is bound to the lvalue result of the conversion
1715 in the second case. */
1716 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1719 return cand
->second_conv
;
1722 /* From this point on, we conceptually need temporaries, even if we
1723 elide them. Only the cases above are "direct bindings". */
1724 if (flags
& LOOKUP_NO_TEMP_BIND
)
1729 When a parameter of reference type is not bound directly to an
1730 argument expression, the conversion sequence is the one required
1731 to convert the argument expression to the underlying type of the
1732 reference according to _over.best.ics_. Conceptually, this
1733 conversion sequence corresponds to copy-initializing a temporary
1734 of the underlying type with the argument expression. Any
1735 difference in top-level cv-qualification is subsumed by the
1736 initialization itself and does not constitute a conversion. */
1740 Otherwise, the reference shall be an lvalue reference to a
1741 non-volatile const type, or the reference shall be an rvalue
1744 We try below to treat this as a bad conversion to improve diagnostics,
1745 but if TO is an incomplete class, we need to reject this conversion
1746 now to avoid unnecessary instantiation. */
1747 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1748 && !COMPLETE_TYPE_P (to
))
1751 /* We're generating a temporary now, but don't bind any more in the
1752 conversion (specifically, don't slice the temporary returned by a
1753 conversion operator). */
1754 flags
|= LOOKUP_NO_TEMP_BIND
;
1756 /* Core issue 899: When [copy-]initializing a temporary to be bound
1757 to the first parameter of a copy constructor (12.8) called with
1758 a single argument in the context of direct-initialization,
1759 explicit conversion functions are also considered.
1761 So don't set LOOKUP_ONLYCONVERTING in that case. */
1762 if (!(flags
& LOOKUP_COPY_PARM
))
1763 flags
|= LOOKUP_ONLYCONVERTING
;
1766 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1771 if (conv
->user_conv_p
)
1773 /* If initializing the temporary used a conversion function,
1774 recalculate the second conversion sequence. */
1775 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1776 if (t
->kind
== ck_user
1777 && DECL_CONV_FN_P (t
->cand
->fn
))
1779 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1780 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1781 conversion
*new_second
1782 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1786 return merge_conversion_sequences (t
, new_second
);
1790 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1791 /* This reference binding, unlike those above, requires the
1792 creation of a temporary. */
1793 conv
->need_temporary_p
= true;
1794 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1798 Otherwise, the reference shall be an lvalue reference to a
1799 non-volatile const type, or the reference shall be an rvalue
1801 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1806 Otherwise, a temporary of type "cv1 T1" is created and
1807 initialized from the initializer expression using the rules for a
1808 non-reference copy initialization. If T1 is reference-related to
1809 T2, cv1 must be the same cv-qualification as, or greater
1810 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1811 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1817 /* Returns the implicit conversion sequence (see [over.ics]) from type
1818 FROM to type TO. The optional expression EXPR may affect the
1819 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1820 true, this conversion is coming from a C-style cast. */
1823 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1824 int flags
, tsubst_flags_t complain
)
1828 if (from
== error_mark_node
|| to
== error_mark_node
1829 || expr
== error_mark_node
)
1832 /* Other flags only apply to the primary function in overload
1833 resolution, or after we've chosen one. */
1834 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1835 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1836 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1838 /* FIXME: actually we don't want warnings either, but we can't just
1839 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1840 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1841 We really ought not to issue that warning until we've committed
1842 to that conversion. */
1843 complain
&= ~tf_error
;
1845 /* Call reshape_init early to remove redundant braces. */
1846 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1847 && CLASS_TYPE_P (to
)
1848 && COMPLETE_TYPE_P (complete_type (to
))
1849 && !CLASSTYPE_NON_AGGREGATE (to
))
1851 expr
= reshape_init (to
, expr
, complain
);
1852 if (expr
== error_mark_node
)
1854 from
= TREE_TYPE (expr
);
1857 if (TYPE_REF_P (to
))
1858 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1860 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1865 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1867 if (is_std_init_list (to
))
1868 return build_list_conv (to
, expr
, flags
, complain
);
1870 /* As an extension, allow list-initialization of _Complex. */
1871 if (TREE_CODE (to
) == COMPLEX_TYPE
)
1873 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1878 /* Allow conversion from an initializer-list with one element to a
1880 if (SCALAR_TYPE_P (to
))
1882 int nelts
= CONSTRUCTOR_NELTS (expr
);
1886 elt
= build_value_init (to
, tf_none
);
1887 else if (nelts
== 1)
1888 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1890 elt
= error_mark_node
;
1892 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1893 c_cast_p
, flags
, complain
);
1896 conv
->check_narrowing
= true;
1897 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1898 /* Too many levels of braces, i.e. '{{1}}'. */
1903 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1904 return build_array_conv (to
, expr
, flags
, complain
);
1907 if (expr
!= NULL_TREE
1908 && (MAYBE_CLASS_TYPE_P (from
)
1909 || MAYBE_CLASS_TYPE_P (to
))
1910 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1912 struct z_candidate
*cand
;
1914 if (CLASS_TYPE_P (to
)
1915 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1916 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1917 return build_aggr_conv (to
, expr
, flags
, complain
);
1919 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
1922 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
1923 && CONSTRUCTOR_NELTS (expr
) == 1
1924 && !is_list_ctor (cand
->fn
))
1926 /* "If C is not an initializer-list constructor and the
1927 initializer list has a single element of type cv U, where U is
1928 X or a class derived from X, the implicit conversion sequence
1929 has Exact Match rank if U is X, or Conversion rank if U is
1931 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1932 tree elttype
= TREE_TYPE (elt
);
1933 if (reference_related_p (to
, elttype
))
1934 return implicit_conversion (to
, elttype
, elt
,
1935 c_cast_p
, flags
, complain
);
1937 conv
= cand
->second_conv
;
1940 /* We used to try to bind a reference to a temporary here, but that
1941 is now handled after the recursive call to this function at the end
1942 of reference_binding. */
1949 /* Like implicit_conversion, but return NULL if the conversion is bad.
1951 This is not static so that check_non_deducible_conversion can call it within
1952 add_template_candidate_real as part of overload resolution; it should not be
1953 called outside of overload resolution. */
1956 good_conversion (tree to
, tree from
, tree expr
,
1957 int flags
, tsubst_flags_t complain
)
1959 conversion
*c
= implicit_conversion (to
, from
, expr
, /*cast*/false,
1966 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1967 functions. ARGS will not be changed until a single candidate is
1970 static struct z_candidate
*
1971 add_candidate (struct z_candidate
**candidates
,
1972 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
1973 size_t num_convs
, conversion
**convs
,
1974 tree access_path
, tree conversion_path
,
1975 int viable
, struct rejection_reason
*reason
,
1978 struct z_candidate
*cand
= (struct z_candidate
*)
1979 conversion_obstack_alloc (sizeof (struct z_candidate
));
1982 cand
->first_arg
= first_arg
;
1984 cand
->convs
= convs
;
1985 cand
->num_convs
= num_convs
;
1986 cand
->access_path
= access_path
;
1987 cand
->conversion_path
= conversion_path
;
1988 cand
->viable
= viable
;
1989 cand
->reason
= reason
;
1990 cand
->next
= *candidates
;
1991 cand
->flags
= flags
;
1997 /* Return the number of remaining arguments in the parameter list
1998 beginning with ARG. */
2001 remaining_arguments (tree arg
)
2005 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
2006 arg
= TREE_CHAIN (arg
))
2012 /* [over.match.copy]: When initializing a temporary object (12.2) to be bound
2013 to the first parameter of a constructor where the parameter is of type
2014 "reference to possibly cv-qualified T" and the constructor is called with a
2015 single argument in the context of direct-initialization of an object of type
2016 "cv2 T", explicit conversion functions are also considered.
2018 So set LOOKUP_COPY_PARM to let reference_binding know that
2019 it's being called in that context. */
2022 conv_flags (int i
, int nargs
, tree fn
, tree arg
, int flags
)
2026 if (i
== 0 && nargs
== 1 && DECL_CONSTRUCTOR_P (fn
)
2027 && (t
= FUNCTION_FIRST_USER_PARMTYPE (fn
))
2028 && (same_type_ignoring_top_level_qualifiers_p
2029 (non_reference (TREE_VALUE (t
)), DECL_CONTEXT (fn
))))
2031 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2032 lflags
|= LOOKUP_COPY_PARM
;
2033 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2034 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2035 lflags
|= LOOKUP_NO_CONVERSION
;
2038 lflags
|= LOOKUP_ONLYCONVERTING
;
2043 /* Create an overload candidate for the function or method FN called
2044 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
2045 FLAGS is passed on to implicit_conversion.
2047 This does not change ARGS.
2049 CTYPE, if non-NULL, is the type we want to pretend this function
2050 comes from for purposes of overload resolution. */
2052 static struct z_candidate
*
2053 add_function_candidate (struct z_candidate
**candidates
,
2054 tree fn
, tree ctype
, tree first_arg
,
2055 const vec
<tree
, va_gc
> *args
, tree access_path
,
2056 tree conversion_path
, int flags
,
2058 tsubst_flags_t complain
)
2060 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2063 tree orig_first_arg
= first_arg
;
2066 struct rejection_reason
*reason
= NULL
;
2068 /* At this point we should not see any functions which haven't been
2069 explicitly declared, except for friend functions which will have
2070 been found using argument dependent lookup. */
2071 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2073 /* The `this', `in_chrg' and VTT arguments to constructors are not
2074 considered in overload resolution. */
2075 if (DECL_CONSTRUCTOR_P (fn
))
2077 if (ctor_omit_inherited_parms (fn
))
2078 /* Bring back parameters omitted from an inherited ctor. */
2079 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2081 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2082 skip
= num_artificial_parms_for (fn
);
2083 if (skip
> 0 && first_arg
!= NULL_TREE
)
2086 first_arg
= NULL_TREE
;
2092 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2094 convs
= alloc_conversions (len
);
2096 /* 13.3.2 - Viable functions [over.match.viable]
2097 First, to be a viable function, a candidate function shall have enough
2098 parameters to agree in number with the arguments in the list.
2100 We need to check this first; otherwise, checking the ICSes might cause
2101 us to produce an ill-formed template instantiation. */
2103 parmnode
= parmlist
;
2104 for (i
= 0; i
< len
; ++i
)
2106 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2108 parmnode
= TREE_CHAIN (parmnode
);
2111 if ((i
< len
&& parmnode
)
2112 || !sufficient_parms_p (parmnode
))
2114 int remaining
= remaining_arguments (parmnode
);
2116 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2119 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2120 parameter of type "reference to cv C" (including such a constructor
2121 instantiated from a template) is excluded from the set of candidate
2122 functions when used to construct an object of type D with an argument list
2123 containing a single argument if C is reference-related to D. */
2124 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2125 && flag_new_inheriting_ctors
2126 && DECL_INHERITED_CTOR (fn
))
2128 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2129 tree dtype
= DECL_CONTEXT (fn
);
2130 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2131 if (reference_related_p (ptype
, dtype
)
2132 && reference_related_p (btype
, ptype
))
2135 reason
= inherited_ctor_rejection ();
2139 /* Second, for a function to be viable, its constraints must be
2141 if (flag_concepts
&& viable
2142 && !constraints_satisfied_p (fn
))
2144 reason
= constraint_failure (fn
);
2148 /* When looking for a function from a subobject from an implicit
2149 copy/move constructor/operator=, don't consider anything that takes (a
2150 reference to) an unrelated type. See c++/44909 and core 1092. */
2151 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2153 if (DECL_CONSTRUCTOR_P (fn
))
2155 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2156 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2162 parmnode
= chain_index (i
-1, parmlist
);
2163 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2168 /* This only applies at the top level. */
2169 flags
&= ~LOOKUP_DEFAULTED
;
2175 /* Third, for F to be a viable function, there shall exist for each
2176 argument an implicit conversion sequence that converts that argument
2177 to the corresponding parameter of F. */
2179 parmnode
= parmlist
;
2181 for (i
= 0; i
< len
; ++i
)
2183 tree argtype
, to_type
;
2188 if (parmnode
== void_list_node
)
2193 /* Already set during deduction. */
2194 parmnode
= TREE_CHAIN (parmnode
);
2198 if (i
== 0 && first_arg
!= NULL_TREE
)
2201 arg
= CONST_CAST_TREE (
2202 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2203 argtype
= lvalue_type (arg
);
2205 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2206 && ! DECL_CONSTRUCTOR_P (fn
));
2210 tree parmtype
= TREE_VALUE (parmnode
);
2212 parmnode
= TREE_CHAIN (parmnode
);
2214 /* The type of the implicit object parameter ('this') for
2215 overload resolution is not always the same as for the
2216 function itself; conversion functions are considered to
2217 be members of the class being converted, and functions
2218 introduced by a using-declaration are considered to be
2219 members of the class that uses them.
2221 Since build_over_call ignores the ICS for the `this'
2222 parameter, we can just change the parm type. */
2223 if (ctype
&& is_this
)
2225 parmtype
= cp_build_qualified_type
2226 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2227 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2229 /* If the function has a ref-qualifier, the implicit
2230 object parameter has reference type. */
2231 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2232 parmtype
= cp_build_reference_type (parmtype
, rv
);
2233 /* The special handling of 'this' conversions in compare_ics
2234 does not apply if there is a ref-qualifier. */
2239 parmtype
= build_pointer_type (parmtype
);
2240 /* We don't use build_this here because we don't want to
2241 capture the object argument until we've chosen a
2242 non-static member function. */
2243 arg
= build_address (arg
);
2244 argtype
= lvalue_type (arg
);
2248 int lflags
= conv_flags (i
, len
-skip
, fn
, arg
, flags
);
2250 t
= implicit_conversion (parmtype
, argtype
, arg
,
2251 /*c_cast_p=*/false, lflags
, complain
);
2256 t
= build_identity_conv (argtype
, arg
);
2257 t
->ellipsis_p
= true;
2268 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
,
2269 EXPR_LOCATION (arg
));
2276 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
,
2277 EXPR_LOCATION (arg
));
2283 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2284 access_path
, conversion_path
, viable
, reason
, flags
);
2287 /* Create an overload candidate for the conversion function FN which will
2288 be invoked for expression OBJ, producing a pointer-to-function which
2289 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2290 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2291 passed on to implicit_conversion.
2293 Actually, we don't really care about FN; we care about the type it
2294 converts to. There may be multiple conversion functions that will
2295 convert to that type, and we rely on build_user_type_conversion_1 to
2296 choose the best one; so when we create our candidate, we record the type
2297 instead of the function. */
2299 static struct z_candidate
*
2300 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2301 const vec
<tree
, va_gc
> *arglist
,
2302 tree access_path
, tree conversion_path
,
2303 tsubst_flags_t complain
)
2305 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2306 int i
, len
, viable
, flags
;
2307 tree parmlist
, parmnode
;
2309 struct rejection_reason
*reason
;
2311 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2312 parmlist
= TREE_TYPE (parmlist
);
2313 parmlist
= TYPE_ARG_TYPES (parmlist
);
2315 len
= vec_safe_length (arglist
) + 1;
2316 convs
= alloc_conversions (len
);
2317 parmnode
= parmlist
;
2319 flags
= LOOKUP_IMPLICIT
;
2322 /* Don't bother looking up the same type twice. */
2323 if (*candidates
&& (*candidates
)->fn
== totype
)
2326 for (i
= 0; i
< len
; ++i
)
2328 tree arg
, argtype
, convert_type
= NULL_TREE
;
2334 arg
= (*arglist
)[i
- 1];
2335 argtype
= lvalue_type (arg
);
2339 t
= build_identity_conv (argtype
, NULL_TREE
);
2340 t
= build_conv (ck_user
, totype
, t
);
2341 /* Leave the 'cand' field null; we'll figure out the conversion in
2342 convert_like_real if this candidate is chosen. */
2343 convert_type
= totype
;
2345 else if (parmnode
== void_list_node
)
2349 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2350 /*c_cast_p=*/false, flags
, complain
);
2351 convert_type
= TREE_VALUE (parmnode
);
2355 t
= build_identity_conv (argtype
, arg
);
2356 t
->ellipsis_p
= true;
2357 convert_type
= argtype
;
2367 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
,
2368 EXPR_LOCATION (arg
));
2375 parmnode
= TREE_CHAIN (parmnode
);
2379 || ! sufficient_parms_p (parmnode
))
2381 int remaining
= remaining_arguments (parmnode
);
2383 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2386 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2387 access_path
, conversion_path
, viable
, reason
, flags
);
2391 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2392 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2393 int flags
, tsubst_flags_t complain
)
2400 struct rejection_reason
*reason
= NULL
;
2405 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2406 convs
= alloc_conversions (num_convs
);
2408 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2409 conversion ops are allowed. We handle that here by just checking for
2410 boolean_type_node because other operators don't ask for it. COND_EXPR
2411 also does contextual conversion to bool for the first operand, but we
2412 handle that in build_conditional_expr, and type1 here is operand 2. */
2413 if (type1
!= boolean_type_node
)
2414 flags
|= LOOKUP_ONLYCONVERTING
;
2416 for (i
= 0; i
< 2; ++i
)
2421 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2422 /*c_cast_p=*/false, flags
, complain
);
2426 /* We need something for printing the candidate. */
2427 t
= build_identity_conv (types
[i
], NULL_TREE
);
2428 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2429 types
[i
], EXPR_LOCATION (args
[i
]));
2434 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2436 EXPR_LOCATION (args
[i
]));
2441 /* For COND_EXPR we rearranged the arguments; undo that now. */
2444 convs
[2] = convs
[1];
2445 convs
[1] = convs
[0];
2446 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2447 /*c_cast_p=*/false, flags
,
2454 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2456 EXPR_LOCATION (args
[2]));
2460 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2462 /*access_path=*/NULL_TREE
,
2463 /*conversion_path=*/NULL_TREE
,
2464 viable
, reason
, flags
);
2468 is_complete (tree t
)
2470 return COMPLETE_TYPE_P (complete_type (t
));
2473 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2476 promoted_arithmetic_type_p (tree type
)
2480 In this section, the term promoted integral type is used to refer
2481 to those integral types which are preserved by integral promotion
2482 (including e.g. int and long but excluding e.g. char).
2483 Similarly, the term promoted arithmetic type refers to promoted
2484 integral types plus floating types. */
2485 return ((CP_INTEGRAL_TYPE_P (type
)
2486 && same_type_p (type_promotes_to (type
), type
))
2487 || TREE_CODE (type
) == REAL_TYPE
);
2490 /* Create any builtin operator overload candidates for the operator in
2491 question given the converted operand types TYPE1 and TYPE2. The other
2492 args are passed through from add_builtin_candidates to
2493 build_builtin_candidate.
2495 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2496 If CODE is requires candidates operands of the same type of the kind
2497 of which TYPE1 and TYPE2 are, we add both candidates
2498 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2501 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2502 enum tree_code code2
, tree fnname
, tree type1
,
2503 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2504 tsubst_flags_t complain
)
2508 case POSTINCREMENT_EXPR
:
2509 case POSTDECREMENT_EXPR
:
2510 args
[1] = integer_zero_node
;
2511 type2
= integer_type_node
;
2520 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2521 and VQ is either volatile or empty, there exist candidate operator
2522 functions of the form
2523 VQ T& operator++(VQ T&);
2524 T operator++(VQ T&, int);
2525 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2526 type other than bool, and VQ is either volatile or empty, there exist
2527 candidate operator functions of the form
2528 VQ T& operator--(VQ T&);
2529 T operator--(VQ T&, int);
2530 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2531 complete object type, and VQ is either volatile or empty, there exist
2532 candidate operator functions of the form
2533 T*VQ& operator++(T*VQ&);
2534 T*VQ& operator--(T*VQ&);
2535 T* operator++(T*VQ&, int);
2536 T* operator--(T*VQ&, int); */
2538 case POSTDECREMENT_EXPR
:
2539 case PREDECREMENT_EXPR
:
2540 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2543 case POSTINCREMENT_EXPR
:
2544 case PREINCREMENT_EXPR
:
2545 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2547 type1
= build_reference_type (type1
);
2552 /* 7 For every cv-qualified or cv-unqualified object type T, there
2553 exist candidate operator functions of the form
2557 8 For every function type T, there exist candidate operator functions of
2559 T& operator*(T*); */
2562 if (TYPE_PTR_P (type1
)
2563 && (TYPE_PTROB_P (type1
)
2564 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2568 /* 9 For every type T, there exist candidate operator functions of the form
2571 10For every promoted arithmetic type T, there exist candidate operator
2572 functions of the form
2576 case UNARY_PLUS_EXPR
: /* unary + */
2577 if (TYPE_PTR_P (type1
))
2581 if (ARITHMETIC_TYPE_P (type1
))
2585 /* 11For every promoted integral type T, there exist candidate operator
2586 functions of the form
2590 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2594 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2595 is the same type as C2 or is a derived class of C2, T is a complete
2596 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2597 there exist candidate operator functions of the form
2598 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2599 where CV12 is the union of CV1 and CV2. */
2602 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2604 tree c1
= TREE_TYPE (type1
);
2605 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2607 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2608 && (TYPE_PTRMEMFUNC_P (type2
)
2609 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2614 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2615 didate operator functions of the form
2620 bool operator<(L, R);
2621 bool operator>(L, R);
2622 bool operator<=(L, R);
2623 bool operator>=(L, R);
2624 bool operator==(L, R);
2625 bool operator!=(L, R);
2626 where LR is the result of the usual arithmetic conversions between
2629 14For every pair of types T and I, where T is a cv-qualified or cv-
2630 unqualified complete object type and I is a promoted integral type,
2631 there exist candidate operator functions of the form
2632 T* operator+(T*, I);
2633 T& operator[](T*, I);
2634 T* operator-(T*, I);
2635 T* operator+(I, T*);
2636 T& operator[](I, T*);
2638 15For every T, where T is a pointer to complete object type, there exist
2639 candidate operator functions of the form112)
2640 ptrdiff_t operator-(T, T);
2642 16For every pointer or enumeration type T, there exist candidate operator
2643 functions of the form
2644 bool operator<(T, T);
2645 bool operator>(T, T);
2646 bool operator<=(T, T);
2647 bool operator>=(T, T);
2648 bool operator==(T, T);
2649 bool operator!=(T, T);
2651 17For every pointer to member type T, there exist candidate operator
2652 functions of the form
2653 bool operator==(T, T);
2654 bool operator!=(T, T); */
2657 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2659 if (TYPE_PTROB_P (type1
)
2660 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2662 type2
= ptrdiff_type_node
;
2667 case TRUNC_DIV_EXPR
:
2668 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2674 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2675 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2677 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2682 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2694 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2696 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2698 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2699 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2701 if (TYPE_PTR_P (type1
)
2702 && null_ptr_cst_p (args
[1]))
2707 if (null_ptr_cst_p (args
[0])
2708 && TYPE_PTR_P (type2
))
2716 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2720 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2722 type1
= ptrdiff_type_node
;
2725 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2727 type2
= ptrdiff_type_node
;
2732 /* 18For every pair of promoted integral types L and R, there exist candi-
2733 date operator functions of the form
2740 where LR is the result of the usual arithmetic conversions between
2743 case TRUNC_MOD_EXPR
:
2749 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2753 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2754 type, VQ is either volatile or empty, and R is a promoted arithmetic
2755 type, there exist candidate operator functions of the form
2756 VQ L& operator=(VQ L&, R);
2757 VQ L& operator*=(VQ L&, R);
2758 VQ L& operator/=(VQ L&, R);
2759 VQ L& operator+=(VQ L&, R);
2760 VQ L& operator-=(VQ L&, R);
2762 20For every pair T, VQ), where T is any type and VQ is either volatile
2763 or empty, there exist candidate operator functions of the form
2764 T*VQ& operator=(T*VQ&, T*);
2766 21For every pair T, VQ), where T is a pointer to member type and VQ is
2767 either volatile or empty, there exist candidate operator functions of
2769 VQ T& operator=(VQ T&, T);
2771 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2772 unqualified complete object type, VQ is either volatile or empty, and
2773 I is a promoted integral type, there exist candidate operator func-
2775 T*VQ& operator+=(T*VQ&, I);
2776 T*VQ& operator-=(T*VQ&, I);
2778 23For every triple L, VQ, R), where L is an integral or enumeration
2779 type, VQ is either volatile or empty, and R is a promoted integral
2780 type, there exist candidate operator functions of the form
2782 VQ L& operator%=(VQ L&, R);
2783 VQ L& operator<<=(VQ L&, R);
2784 VQ L& operator>>=(VQ L&, R);
2785 VQ L& operator&=(VQ L&, R);
2786 VQ L& operator^=(VQ L&, R);
2787 VQ L& operator|=(VQ L&, R); */
2794 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2796 type2
= ptrdiff_type_node
;
2801 case TRUNC_DIV_EXPR
:
2802 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2806 case TRUNC_MOD_EXPR
:
2812 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2817 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2819 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2820 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2821 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2822 || ((TYPE_PTRMEMFUNC_P (type1
)
2823 || TYPE_PTR_P (type1
))
2824 && null_ptr_cst_p (args
[1])))
2834 type1
= build_reference_type (type1
);
2840 For every pair of promoted arithmetic types L and R, there
2841 exist candidate operator functions of the form
2843 LR operator?(bool, L, R);
2845 where LR is the result of the usual arithmetic conversions
2846 between types L and R.
2848 For every type T, where T is a pointer or pointer-to-member
2849 type, there exist candidate operator functions of the form T
2850 operator?(bool, T, T); */
2852 if (promoted_arithmetic_type_p (type1
)
2853 && promoted_arithmetic_type_p (type2
))
2857 /* Otherwise, the types should be pointers. */
2858 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2861 /* We don't check that the two types are the same; the logic
2862 below will actually create two candidates; one in which both
2863 parameter types are TYPE1, and one in which both parameter
2869 if (ARITHMETIC_TYPE_P (type1
))
2877 /* Make sure we don't create builtin candidates with dependent types. */
2878 bool u1
= uses_template_parms (type1
);
2879 bool u2
= type2
? uses_template_parms (type2
) : false;
2882 /* Try to recover if one of the types is non-dependent. But if
2883 there's only one type, there's nothing we can do. */
2886 /* And we lose if both are dependent. */
2889 /* Or if they have different forms. */
2890 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2899 /* If we're dealing with two pointer types or two enumeral types,
2900 we need candidates for both of them. */
2901 if (type2
&& !same_type_p (type1
, type2
)
2902 && TREE_CODE (type1
) == TREE_CODE (type2
)
2903 && (TYPE_REF_P (type1
)
2904 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2905 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2906 || TYPE_PTRMEMFUNC_P (type1
)
2907 || MAYBE_CLASS_TYPE_P (type1
)
2908 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2910 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2912 tree cptype
= composite_pointer_type (type1
, type2
,
2917 if (cptype
!= error_mark_node
)
2919 build_builtin_candidate
2920 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
2926 build_builtin_candidate
2927 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
2928 build_builtin_candidate
2929 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
2933 build_builtin_candidate
2934 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
2938 type_decays_to (tree type
)
2940 if (TREE_CODE (type
) == ARRAY_TYPE
)
2941 return build_pointer_type (TREE_TYPE (type
));
2942 if (TREE_CODE (type
) == FUNCTION_TYPE
)
2943 return build_pointer_type (type
);
2947 /* There are three conditions of builtin candidates:
2949 1) bool-taking candidates. These are the same regardless of the input.
2950 2) pointer-pair taking candidates. These are generated for each type
2951 one of the input types converts to.
2952 3) arithmetic candidates. According to the standard, we should generate
2953 all of these, but I'm trying not to...
2955 Here we generate a superset of the possible candidates for this particular
2956 case. That is a subset of the full set the standard defines, plus some
2957 other cases which the standard disallows. add_builtin_candidate will
2958 filter out the invalid set. */
2961 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
2962 enum tree_code code2
, tree fnname
, tree
*args
,
2963 int flags
, tsubst_flags_t complain
)
2967 tree type
, argtypes
[3], t
;
2968 /* TYPES[i] is the set of possible builtin-operator parameter types
2969 we will consider for the Ith argument. */
2970 vec
<tree
, va_gc
> *types
[2];
2973 for (i
= 0; i
< 3; ++i
)
2976 argtypes
[i
] = unlowered_expr_type (args
[i
]);
2978 argtypes
[i
] = NULL_TREE
;
2983 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2984 and VQ is either volatile or empty, there exist candidate operator
2985 functions of the form
2986 VQ T& operator++(VQ T&); */
2988 case POSTINCREMENT_EXPR
:
2989 case PREINCREMENT_EXPR
:
2990 case POSTDECREMENT_EXPR
:
2991 case PREDECREMENT_EXPR
:
2996 /* 24There also exist candidate operator functions of the form
2997 bool operator!(bool);
2998 bool operator&&(bool, bool);
2999 bool operator||(bool, bool); */
3001 case TRUTH_NOT_EXPR
:
3002 build_builtin_candidate
3003 (candidates
, fnname
, boolean_type_node
,
3004 NULL_TREE
, args
, argtypes
, flags
, complain
);
3007 case TRUTH_ORIF_EXPR
:
3008 case TRUTH_ANDIF_EXPR
:
3009 build_builtin_candidate
3010 (candidates
, fnname
, boolean_type_node
,
3011 boolean_type_node
, args
, argtypes
, flags
, complain
);
3033 types
[0] = make_tree_vector ();
3034 types
[1] = make_tree_vector ();
3036 for (i
= 0; i
< 2; ++i
)
3040 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
3044 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
3047 convs
= lookup_conversions (argtypes
[i
]);
3049 if (code
== COND_EXPR
)
3051 if (lvalue_p (args
[i
]))
3052 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3054 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3060 for (; convs
; convs
= TREE_CHAIN (convs
))
3062 type
= TREE_TYPE (convs
);
3065 && (!TYPE_REF_P (type
)
3066 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3069 if (code
== COND_EXPR
&& TYPE_REF_P (type
))
3070 vec_safe_push (types
[i
], type
);
3072 type
= non_reference (type
);
3073 if (i
!= 0 || ! ref1
)
3075 type
= cv_unqualified (type_decays_to (type
));
3076 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3077 vec_safe_push (types
[i
], type
);
3078 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3079 type
= type_promotes_to (type
);
3082 if (! vec_member (type
, types
[i
]))
3083 vec_safe_push (types
[i
], type
);
3088 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3089 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3090 type
= non_reference (argtypes
[i
]);
3091 if (i
!= 0 || ! ref1
)
3093 type
= cv_unqualified (type_decays_to (type
));
3094 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3095 vec_safe_push (types
[i
], type
);
3096 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3097 type
= type_promotes_to (type
);
3099 vec_safe_push (types
[i
], type
);
3103 /* Run through the possible parameter types of both arguments,
3104 creating candidates with those parameter types. */
3105 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3110 if (!types
[1]->is_empty ())
3111 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3112 add_builtin_candidate
3113 (candidates
, code
, code2
, fnname
, t
,
3114 u
, args
, argtypes
, flags
, complain
);
3116 add_builtin_candidate
3117 (candidates
, code
, code2
, fnname
, t
,
3118 NULL_TREE
, args
, argtypes
, flags
, complain
);
3121 release_tree_vector (types
[0]);
3122 release_tree_vector (types
[1]);
3126 /* If TMPL can be successfully instantiated as indicated by
3127 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3129 TMPL is the template. EXPLICIT_TARGS are any explicit template
3130 arguments. ARGLIST is the arguments provided at the call-site.
3131 This does not change ARGLIST. The RETURN_TYPE is the desired type
3132 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3133 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3134 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3136 static struct z_candidate
*
3137 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3138 tree ctype
, tree explicit_targs
, tree first_arg
,
3139 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3140 tree access_path
, tree conversion_path
,
3141 int flags
, tree obj
, unification_kind_t strict
,
3142 tsubst_flags_t complain
)
3144 int ntparms
= DECL_NTPARMS (tmpl
);
3145 tree targs
= make_tree_vec (ntparms
);
3146 unsigned int len
= vec_safe_length (arglist
);
3147 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3148 unsigned int skip_without_in_chrg
= 0;
3149 tree first_arg_without_in_chrg
= first_arg
;
3150 tree
*args_without_in_chrg
;
3151 unsigned int nargs_without_in_chrg
;
3152 unsigned int ia
, ix
;
3154 struct z_candidate
*cand
;
3156 struct rejection_reason
*reason
= NULL
;
3158 conversion
**convs
= NULL
;
3160 /* We don't do deduction on the in-charge parameter, the VTT
3161 parameter or 'this'. */
3162 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3164 if (first_arg_without_in_chrg
!= NULL_TREE
)
3165 first_arg_without_in_chrg
= NULL_TREE
;
3166 else if (return_type
&& strict
== DEDUCE_CALL
)
3167 /* We're deducing for a call to the result of a template conversion
3168 function, so the args don't contain 'this'; leave them alone. */;
3170 ++skip_without_in_chrg
;
3173 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3174 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3175 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3177 if (first_arg_without_in_chrg
!= NULL_TREE
)
3178 first_arg_without_in_chrg
= NULL_TREE
;
3180 ++skip_without_in_chrg
;
3183 if (len
< skip_without_in_chrg
)
3186 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3187 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3188 TREE_TYPE ((*arglist
)[0])))
3190 /* 12.8/6 says, "A declaration of a constructor for a class X is
3191 ill-formed if its first parameter is of type (optionally cv-qualified)
3192 X and either there are no other parameters or else all other
3193 parameters have default arguments. A member function template is never
3194 instantiated to produce such a constructor signature."
3196 So if we're trying to copy an object of the containing class, don't
3197 consider a template constructor that has a first parameter type that
3198 is just a template parameter, as we would deduce a signature that we
3199 would then reject in the code below. */
3200 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3202 firstparm
= TREE_VALUE (firstparm
);
3203 if (PACK_EXPANSION_P (firstparm
))
3204 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3205 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3207 gcc_assert (!explicit_targs
);
3208 reason
= invalid_copy_with_fn_template_rejection ();
3214 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3215 + (len
- skip_without_in_chrg
));
3216 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3218 if (first_arg_without_in_chrg
!= NULL_TREE
)
3220 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3223 for (ix
= skip_without_in_chrg
;
3224 vec_safe_iterate (arglist
, ix
, &arg
);
3227 args_without_in_chrg
[ia
] = arg
;
3230 gcc_assert (ia
== nargs_without_in_chrg
);
3232 errs
= errorcount
+sorrycount
;
3234 convs
= alloc_conversions (nargs
);
3235 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3236 args_without_in_chrg
,
3237 nargs_without_in_chrg
,
3238 return_type
, strict
, flags
, convs
,
3239 false, complain
& tf_decltype
);
3241 if (fn
== error_mark_node
)
3243 /* Don't repeat unification later if it already resulted in errors. */
3244 if (errorcount
+sorrycount
== errs
)
3245 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3246 targs
, args_without_in_chrg
,
3247 nargs_without_in_chrg
,
3248 return_type
, strict
, flags
);
3250 reason
= template_unification_error_rejection ();
3254 /* Now the explicit specifier might have been deduced; check if this
3255 declaration is explicit. If it is and we're ignoring non-converting
3256 constructors, don't add this function to the set of candidates. */
3257 if ((flags
& LOOKUP_ONLYCONVERTING
) && DECL_NONCONVERTING_P (fn
))
3260 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3262 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3263 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3266 /* We're trying to produce a constructor with a prohibited signature,
3267 as discussed above; handle here any cases we didn't catch then,
3269 reason
= invalid_copy_with_fn_template_rejection ();
3274 if (obj
!= NULL_TREE
)
3275 /* Aha, this is a conversion function. */
3276 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3277 access_path
, conversion_path
, complain
);
3279 cand
= add_function_candidate (candidates
, fn
, ctype
,
3280 first_arg
, arglist
, access_path
,
3281 conversion_path
, flags
, convs
, complain
);
3282 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3283 /* This situation can occur if a member template of a template
3284 class is specialized. Then, instantiate_template might return
3285 an instantiation of the specialization, in which case the
3286 DECL_TI_TEMPLATE field will point at the original
3287 specialization. For example:
3289 template <class T> struct S { template <class U> void f(U);
3290 template <> void f(int) {}; };
3294 Here, TMPL will be template <class U> S<double>::f(U).
3295 And, instantiate template will give us the specialization
3296 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3297 for this will point at template <class T> template <> S<T>::f(int),
3298 so that we can find the definition. For the purposes of
3299 overload resolution, however, we want the original TMPL. */
3300 cand
->template_decl
= build_template_info (tmpl
, targs
);
3302 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3303 cand
->explicit_targs
= explicit_targs
;
3307 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3308 access_path
, conversion_path
, 0, reason
, flags
);
3312 static struct z_candidate
*
3313 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3314 tree explicit_targs
, tree first_arg
,
3315 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3316 tree access_path
, tree conversion_path
, int flags
,
3317 unification_kind_t strict
, tsubst_flags_t complain
)
3320 add_template_candidate_real (candidates
, tmpl
, ctype
,
3321 explicit_targs
, first_arg
, arglist
,
3322 return_type
, access_path
, conversion_path
,
3323 flags
, NULL_TREE
, strict
, complain
);
3326 /* Create an overload candidate for the conversion function template TMPL,
3327 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3328 pointer-to-function which will in turn be called with the argument list
3329 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3330 passed on to implicit_conversion. */
3332 static struct z_candidate
*
3333 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3335 const vec
<tree
, va_gc
> *arglist
,
3336 tree return_type
, tree access_path
,
3337 tree conversion_path
, tsubst_flags_t complain
)
3339 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3340 core issue 2189, let's disable this candidate if there are any call
3346 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3347 NULL_TREE
, arglist
, return_type
, access_path
,
3348 conversion_path
, 0, obj
, DEDUCE_CALL
,
3352 /* The CANDS are the set of candidates that were considered for
3353 overload resolution. Return the set of viable candidates, or CANDS
3354 if none are viable. If any of the candidates were viable, set
3355 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3356 considered viable only if it is strictly viable. */
3358 static struct z_candidate
*
3359 splice_viable (struct z_candidate
*cands
,
3363 struct z_candidate
*viable
;
3364 struct z_candidate
**last_viable
;
3365 struct z_candidate
**cand
;
3366 bool found_strictly_viable
= false;
3368 /* Be strict inside templates, since build_over_call won't actually
3369 do the conversions to get pedwarns. */
3370 if (processing_template_decl
)
3374 last_viable
= &viable
;
3375 *any_viable_p
= false;
3380 struct z_candidate
*c
= *cand
;
3382 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3384 /* Be strict in the presence of a viable candidate. Also if
3385 there are template candidates, so that we get deduction errors
3386 for them instead of silently preferring a bad conversion. */
3388 if (viable
&& !found_strictly_viable
)
3390 /* Put any spliced near matches back onto the main list so
3391 that we see them if there is no strict match. */
3392 *any_viable_p
= false;
3393 *last_viable
= cands
;
3396 last_viable
= &viable
;
3400 if (strict_p
? c
->viable
== 1 : c
->viable
)
3405 last_viable
= &c
->next
;
3406 *any_viable_p
= true;
3408 found_strictly_viable
= true;
3414 return viable
? viable
: cands
;
3418 any_strictly_viable (struct z_candidate
*cands
)
3420 for (; cands
; cands
= cands
->next
)
3421 if (cands
->viable
== 1)
3426 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3427 words, it is about to become the "this" pointer for a member
3428 function call. Take the address of the object. */
3431 build_this (tree obj
)
3433 /* In a template, we are only concerned about the type of the
3434 expression, so we can take a shortcut. */
3435 if (processing_template_decl
)
3436 return build_address (obj
);
3438 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3441 /* Returns true iff functions are equivalent. Equivalent functions are
3442 not '==' only if one is a function-local extern function or if
3443 both are extern "C". */
3446 equal_functions (tree fn1
, tree fn2
)
3448 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3450 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3452 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3453 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3454 return decls_match (fn1
, fn2
);
3458 /* Print information about a candidate FN being rejected due to INFO. */
3461 print_conversion_rejection (location_t loc
, struct conversion_info
*info
,
3464 tree from
= info
->from
;
3466 from
= lvalue_type (from
);
3467 if (info
->n_arg
== -1)
3469 /* Conversion of implicit `this' argument failed. */
3470 if (!TYPE_P (info
->from
))
3471 /* A bad conversion for 'this' must be discarding cv-quals. */
3472 inform (loc
, " passing %qT as %<this%> "
3473 "argument discards qualifiers",
3476 inform (loc
, " no known conversion for implicit "
3477 "%<this%> parameter from %qH to %qI",
3478 from
, info
->to_type
);
3480 else if (!TYPE_P (info
->from
))
3482 if (info
->n_arg
>= 0)
3483 inform (loc
, " conversion of argument %d would be ill-formed:",
3485 perform_implicit_conversion (info
->to_type
, info
->from
,
3486 tf_warning_or_error
);
3488 else if (info
->n_arg
== -2)
3489 /* Conversion of conversion function return value failed. */
3490 inform (loc
, " no known conversion from %qH to %qI",
3491 from
, info
->to_type
);
3494 if (TREE_CODE (fn
) == FUNCTION_DECL
)
3495 loc
= get_fndecl_argument_location (fn
, info
->n_arg
);
3496 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3497 info
->n_arg
+ 1, from
, info
->to_type
);
3501 /* Print information about a candidate with WANT parameters and we found
3505 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3507 inform_n (loc
, want
,
3508 " candidate expects %d argument, %d provided",
3509 " candidate expects %d arguments, %d provided",
3513 /* Print information about one overload candidate CANDIDATE. MSGSTR
3514 is the text to print before the candidate itself.
3516 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3517 to have been run through gettext by the caller. This wart makes
3518 life simpler in print_z_candidates and for the translators. */
3521 print_z_candidate (location_t loc
, const char *msgstr
,
3522 struct z_candidate
*candidate
)
3524 const char *msg
= (msgstr
== NULL
3526 : ACONCAT ((msgstr
, " ", NULL
)));
3527 tree fn
= candidate
->fn
;
3528 if (flag_new_inheriting_ctors
)
3529 fn
= strip_inheriting_ctors (fn
);
3530 location_t cloc
= location_of (fn
);
3532 if (identifier_p (fn
))
3535 if (candidate
->num_convs
== 3)
3536 inform (cloc
, "%s%<%D(%T, %T, %T)%> <built-in>", msg
, fn
,
3537 candidate
->convs
[0]->type
,
3538 candidate
->convs
[1]->type
,
3539 candidate
->convs
[2]->type
);
3540 else if (candidate
->num_convs
== 2)
3541 inform (cloc
, "%s%<%D(%T, %T)%> <built-in>", msg
, fn
,
3542 candidate
->convs
[0]->type
,
3543 candidate
->convs
[1]->type
);
3545 inform (cloc
, "%s%<%D(%T)%> <built-in>", msg
, fn
,
3546 candidate
->convs
[0]->type
);
3548 else if (TYPE_P (fn
))
3549 inform (cloc
, "%s%qT <conversion>", msg
, fn
);
3550 else if (candidate
->viable
== -1)
3551 inform (cloc
, "%s%#qD <near match>", msg
, fn
);
3552 else if (DECL_DELETED_FN (fn
))
3553 inform (cloc
, "%s%#qD <deleted>", msg
, fn
);
3555 inform (cloc
, "%s%#qD", msg
, fn
);
3556 if (fn
!= candidate
->fn
)
3558 cloc
= location_of (candidate
->fn
);
3559 inform (cloc
, " inherited here");
3561 /* Give the user some information about why this candidate failed. */
3562 if (candidate
->reason
!= NULL
)
3564 struct rejection_reason
*r
= candidate
->reason
;
3569 print_arity_information (cloc
, r
->u
.arity
.actual
,
3570 r
->u
.arity
.expected
);
3572 case rr_arg_conversion
:
3573 print_conversion_rejection (cloc
, &r
->u
.conversion
, fn
);
3575 case rr_bad_arg_conversion
:
3576 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
, fn
);
3578 case rr_explicit_conversion
:
3579 inform (cloc
, " return type %qT of explicit conversion function "
3580 "cannot be converted to %qT with a qualification "
3581 "conversion", r
->u
.conversion
.from
,
3582 r
->u
.conversion
.to_type
);
3584 case rr_template_conversion
:
3585 inform (cloc
, " conversion from return type %qT of template "
3586 "conversion function specialization to %qT is not an "
3587 "exact match", r
->u
.conversion
.from
,
3588 r
->u
.conversion
.to_type
);
3590 case rr_template_unification
:
3591 /* We use template_unification_error_rejection if unification caused
3592 actual non-SFINAE errors, in which case we don't need to repeat
3594 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3596 inform (cloc
, " substitution of deduced template arguments "
3597 "resulted in errors seen above");
3600 /* Re-run template unification with diagnostics. */
3601 inform (cloc
, " template argument deduction/substitution failed:");
3602 fn_type_unification (r
->u
.template_unification
.tmpl
,
3603 r
->u
.template_unification
.explicit_targs
,
3605 (r
->u
.template_unification
.num_targs
)),
3606 r
->u
.template_unification
.args
,
3607 r
->u
.template_unification
.nargs
,
3608 r
->u
.template_unification
.return_type
,
3609 r
->u
.template_unification
.strict
,
3610 r
->u
.template_unification
.flags
,
3613 case rr_invalid_copy
:
3615 " a constructor taking a single argument of its own "
3616 "class type is invalid");
3618 case rr_constraint_failure
:
3620 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3621 tree args
= r
->u
.template_instantiation
.targs
;
3622 diagnose_constraints (cloc
, tmpl
, args
);
3625 case rr_inherited_ctor
:
3626 inform (cloc
, " an inherited constructor is not a candidate for "
3627 "initialization from an expression of the same or derived "
3632 /* This candidate didn't have any issues or we failed to
3633 handle a particular code. Either way... */
3640 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3642 struct z_candidate
*cand1
;
3643 struct z_candidate
**cand2
;
3648 /* Remove non-viable deleted candidates. */
3650 for (cand2
= &cand1
; *cand2
; )
3652 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3653 && !(*cand2
)->viable
3654 && DECL_DELETED_FN ((*cand2
)->fn
))
3655 *cand2
= (*cand2
)->next
;
3657 cand2
= &(*cand2
)->next
;
3659 /* ...if there are any non-deleted ones. */
3663 /* There may be duplicates in the set of candidates. We put off
3664 checking this condition as long as possible, since we have no way
3665 to eliminate duplicates from a set of functions in less than n^2
3666 time. Now we are about to emit an error message, so it is more
3667 permissible to go slowly. */
3668 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3670 tree fn
= cand1
->fn
;
3671 /* Skip builtin candidates and conversion functions. */
3674 cand2
= &cand1
->next
;
3677 if (DECL_P ((*cand2
)->fn
)
3678 && equal_functions (fn
, (*cand2
)->fn
))
3679 *cand2
= (*cand2
)->next
;
3681 cand2
= &(*cand2
)->next
;
3685 for (; candidates
; candidates
= candidates
->next
)
3686 print_z_candidate (loc
, "candidate:", candidates
);
3689 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3690 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3691 the result of the conversion function to convert it to the final
3692 desired type. Merge the two sequences into a single sequence,
3693 and return the merged sequence. */
3696 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3699 bool bad
= user_seq
->bad_p
;
3701 gcc_assert (user_seq
->kind
== ck_user
);
3703 /* Find the end of the second conversion sequence. */
3704 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3706 /* The entire sequence is a user-conversion sequence. */
3707 (*t
)->user_conv_p
= true;
3712 if ((*t
)->rvaluedness_matches_p
)
3713 /* We're binding a reference directly to the result of the conversion.
3714 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3715 type, but we want it back. */
3716 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3718 /* Replace the identity conversion with the user conversion
3725 /* Handle overload resolution for initializing an object of class type from
3726 an initializer list. First we look for a suitable constructor that
3727 takes a std::initializer_list; if we don't find one, we then look for a
3728 non-list constructor.
3730 Parameters are as for add_candidates, except that the arguments are in
3731 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3732 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3735 add_list_candidates (tree fns
, tree first_arg
,
3736 const vec
<tree
, va_gc
> *args
, tree totype
,
3737 tree explicit_targs
, bool template_only
,
3738 tree conversion_path
, tree access_path
,
3740 struct z_candidate
**candidates
,
3741 tsubst_flags_t complain
)
3743 gcc_assert (*candidates
== NULL
);
3745 /* We're looking for a ctor for list-initialization. */
3746 flags
|= LOOKUP_LIST_INIT_CTOR
;
3747 /* And we don't allow narrowing conversions. We also use this flag to
3748 avoid the copy constructor call for copy-list-initialization. */
3749 flags
|= LOOKUP_NO_NARROWING
;
3751 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3752 tree init_list
= (*args
)[nart
];
3754 /* Always use the default constructor if the list is empty (DR 990). */
3755 if (CONSTRUCTOR_NELTS (init_list
) == 0
3756 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3758 /* If the class has a list ctor, try passing the list as a single
3759 argument first, but only consider list ctors. */
3760 else if (TYPE_HAS_LIST_CTOR (totype
))
3762 flags
|= LOOKUP_LIST_ONLY
;
3763 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3764 explicit_targs
, template_only
, conversion_path
,
3765 access_path
, flags
, candidates
, complain
);
3766 if (any_strictly_viable (*candidates
))
3770 /* Expand the CONSTRUCTOR into a new argument vec. */
3771 vec
<tree
, va_gc
> *new_args
;
3772 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3773 for (unsigned i
= 0; i
< nart
; ++i
)
3774 new_args
->quick_push ((*args
)[i
]);
3775 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3776 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3778 /* We aren't looking for list-ctors anymore. */
3779 flags
&= ~LOOKUP_LIST_ONLY
;
3780 /* We allow more user-defined conversions within an init-list. */
3781 flags
&= ~LOOKUP_NO_CONVERSION
;
3783 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3784 explicit_targs
, template_only
, conversion_path
,
3785 access_path
, flags
, candidates
, complain
);
3788 /* Returns the best overload candidate to perform the requested
3789 conversion. This function is used for three the overloading situations
3790 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3791 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3792 per [dcl.init.ref], so we ignore temporary bindings. */
3794 static struct z_candidate
*
3795 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3796 tsubst_flags_t complain
)
3798 struct z_candidate
*candidates
, *cand
;
3800 tree ctors
= NULL_TREE
;
3801 tree conv_fns
= NULL_TREE
;
3802 conversion
*conv
= NULL
;
3803 tree first_arg
= NULL_TREE
;
3804 vec
<tree
, va_gc
> *args
= NULL
;
3811 fromtype
= TREE_TYPE (expr
);
3813 /* We represent conversion within a hierarchy using RVALUE_CONV and
3814 BASE_CONV, as specified by [over.best.ics]; these become plain
3815 constructor calls, as specified in [dcl.init]. */
3816 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3817 || !DERIVED_FROM_P (totype
, fromtype
));
3819 if (CLASS_TYPE_P (totype
))
3820 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3821 creating a garbage BASELINK; constructors can't be inherited. */
3822 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3824 if (MAYBE_CLASS_TYPE_P (fromtype
))
3826 tree to_nonref
= non_reference (totype
);
3827 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3828 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3829 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3831 /* [class.conv.fct] A conversion function is never used to
3832 convert a (possibly cv-qualified) object to the (possibly
3833 cv-qualified) same object type (or a reference to it), to a
3834 (possibly cv-qualified) base class of that type (or a
3835 reference to it)... */
3838 conv_fns
= lookup_conversions (fromtype
);
3842 flags
|= LOOKUP_NO_CONVERSION
;
3843 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3844 flags
|= LOOKUP_NO_NARROWING
;
3846 /* It's OK to bind a temporary for converting constructor arguments, but
3847 not in converting the return value of a conversion operator. */
3848 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3849 | (flags
& LOOKUP_NO_NARROWING
));
3850 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3854 int ctorflags
= flags
;
3856 first_arg
= build_dummy_object (totype
);
3858 /* We should never try to call the abstract or base constructor
3860 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3861 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3863 args
= make_tree_vector_single (expr
);
3864 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3866 /* List-initialization. */
3867 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3868 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3869 ctorflags
, &candidates
, complain
);
3873 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3874 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3875 ctorflags
, &candidates
, complain
);
3878 for (cand
= candidates
; cand
; cand
= cand
->next
)
3880 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3882 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3883 set, then this is copy-initialization. In that case, "The
3884 result of the call is then used to direct-initialize the
3885 object that is the destination of the copy-initialization."
3888 We represent this in the conversion sequence with an
3889 rvalue conversion, which means a constructor call. */
3890 if (!TYPE_REF_P (totype
)
3891 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3893 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3899 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3900 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3905 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3907 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3908 struct z_candidate
*old_candidates
;
3910 /* If we are called to convert to a reference type, we are trying to
3911 find a direct binding, so don't even consider temporaries. If
3912 we don't find a direct binding, the caller will try again to
3913 look for a temporary binding. */
3914 if (TYPE_REF_P (totype
))
3915 convflags
|= LOOKUP_NO_TEMP_BIND
;
3917 old_candidates
= candidates
;
3918 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3920 conversion_path
, TYPE_BINFO (fromtype
),
3921 flags
, &candidates
, complain
);
3923 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
3925 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
3927 = implicit_conversion (totype
,
3930 /*c_cast_p=*/false, convflags
,
3933 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3934 copy-initialization. In that case, "The result of the
3935 call is then used to direct-initialize the object that is
3936 the destination of the copy-initialization." [dcl.init]
3938 We represent this in the conversion sequence with an
3939 rvalue conversion, which means a constructor call. But
3940 don't add a second rvalue conversion if there's already
3941 one there. Which there really shouldn't be, but it's
3942 harmless since we'd add it here anyway. */
3943 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
3944 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3945 ics
= build_conv (ck_rvalue
, totype
, ics
);
3947 cand
->second_conv
= ics
;
3952 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
3954 EXPR_LOCATION (expr
));
3956 else if (DECL_NONCONVERTING_P (cand
->fn
)
3957 && ics
->rank
> cr_exact
)
3959 /* 13.3.1.5: For direct-initialization, those explicit
3960 conversion functions that are not hidden within S and
3961 yield type T or a type that can be converted to type T
3962 with a qualification conversion (4.4) are also candidate
3964 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3965 I've raised this issue with the committee. --jason 9/2011 */
3967 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
3969 else if (cand
->viable
== 1 && ics
->bad_p
)
3973 = bad_arg_conversion_rejection (NULL_TREE
, -2,
3975 EXPR_LOCATION (expr
));
3977 else if (primary_template_specialization_p (cand
->fn
)
3978 && ics
->rank
> cr_exact
)
3980 /* 13.3.3.1.2: If the user-defined conversion is specified by
3981 a specialization of a conversion function template, the
3982 second standard conversion sequence shall have exact match
3985 cand
->reason
= template_conversion_rejection (rettype
, totype
);
3990 candidates
= splice_viable (candidates
, false, &any_viable_p
);
3994 release_tree_vector (args
);
3998 cand
= tourney (candidates
, complain
);
4001 if (complain
& tf_error
)
4003 auto_diagnostic_group d
;
4004 error ("conversion from %qH to %qI is ambiguous",
4006 print_z_candidates (location_of (expr
), candidates
);
4009 cand
= candidates
; /* any one will do */
4010 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
4011 cand
->second_conv
->user_conv_p
= true;
4012 if (!any_strictly_viable (candidates
))
4013 cand
->second_conv
->bad_p
= true;
4014 if (flags
& LOOKUP_ONLYCONVERTING
)
4015 cand
->second_conv
->need_temporary_p
= true;
4016 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
4017 ambiguous conversion is no worse than another user-defined
4024 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
4025 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
4026 else if (cand
->second_conv
->kind
== ck_rvalue
)
4027 /* DR 5: [in the first step of copy-initialization]...if the function
4028 is a constructor, the call initializes a temporary of the
4029 cv-unqualified version of the destination type. */
4030 convtype
= cv_unqualified (totype
);
4033 /* Build the user conversion sequence. */
4037 build_identity_conv (TREE_TYPE (expr
), expr
));
4039 if (cand
->viable
== -1)
4042 /* We're performing the maybe-rvalue overload resolution and
4043 a conversion function is in play. Reject converting the return
4044 value of the conversion function to a base class. */
4045 if ((flags
& LOOKUP_PREFER_RVALUE
) && !DECL_CONSTRUCTOR_P (cand
->fn
))
4046 for (conversion
*t
= cand
->second_conv
; t
; t
= next_conversion (t
))
4047 if (t
->kind
== ck_base
)
4050 /* Remember that this was a list-initialization. */
4051 if (flags
& LOOKUP_NO_NARROWING
)
4052 conv
->check_narrowing
= true;
4054 /* Combine it with the second conversion sequence. */
4055 cand
->second_conv
= merge_conversion_sequences (conv
,
4061 /* Wrapper for above. */
4064 build_user_type_conversion (tree totype
, tree expr
, int flags
,
4065 tsubst_flags_t complain
)
4067 struct z_candidate
*cand
;
4070 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4071 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
4075 if (cand
->second_conv
->kind
== ck_ambig
)
4076 ret
= error_mark_node
;
4079 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4080 ret
= convert_from_reference (expr
);
4086 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4090 /* Subroutine of convert_nontype_argument.
4092 EXPR is an expression used in a context that requires a converted
4093 constant-expression, such as a template non-type parameter. Do any
4094 necessary conversions (that are permitted for converted
4095 constant-expressions) to convert it to the desired type.
4097 If conversion is successful, returns the converted expression;
4098 otherwise, returns error_mark_node. */
4101 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4106 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
4108 if (error_operand_p (expr
))
4109 return error_mark_node
;
4111 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4112 p
= conversion_obstack_alloc (0);
4114 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4116 LOOKUP_IMPLICIT
, complain
);
4118 /* A converted constant expression of type T is an expression, implicitly
4119 converted to type T, where the converted expression is a constant
4120 expression and the implicit conversion sequence contains only
4122 * user-defined conversions,
4123 * lvalue-to-rvalue conversions (7.1),
4124 * array-to-pointer conversions (7.2),
4125 * function-to-pointer conversions (7.3),
4126 * qualification conversions (7.5),
4127 * integral promotions (7.6),
4128 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4129 * null pointer conversions (7.11) from std::nullptr_t,
4130 * null member pointer conversions (7.12) from std::nullptr_t, and
4131 * function pointer conversions (7.13),
4133 and where the reference binding (if any) binds directly. */
4135 for (conversion
*c
= conv
;
4136 conv
&& c
->kind
!= ck_identity
;
4137 c
= next_conversion (c
))
4141 /* A conversion function is OK. If it isn't constexpr, we'll
4142 complain later that the argument isn't constant. */
4144 /* The lvalue-to-rvalue conversion is OK. */
4146 /* Array-to-pointer and function-to-pointer. */
4148 /* Function pointer conversions. */
4150 /* Qualification conversions. */
4155 if (c
->need_temporary_p
)
4157 if (complain
& tf_error
)
4158 error_at (loc
, "initializing %qH with %qI in converted "
4159 "constant expression does not bind directly",
4160 type
, next_conversion (c
)->type
);
4169 t
= next_conversion (c
)->type
;
4170 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4171 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4172 /* Integral promotion or conversion. */
4174 if (NULLPTR_TYPE_P (t
))
4175 /* Conversion from nullptr to pointer or pointer-to-member. */
4178 if (complain
& tf_error
)
4179 error_at (loc
, "conversion from %qH to %qI in a "
4180 "converted constant expression", t
, type
);
4189 /* Avoid confusing convert_nontype_argument by introducing
4190 a redundant conversion to the same reference type. */
4191 if (conv
&& conv
->kind
== ck_ref_bind
4192 && REFERENCE_REF_P (expr
))
4194 tree ref
= TREE_OPERAND (expr
, 0);
4195 if (same_type_p (type
, TREE_TYPE (ref
)))
4201 conv
->check_narrowing
= true;
4202 conv
->check_narrowing_const_only
= true;
4203 expr
= convert_like (conv
, expr
, complain
);
4207 if (complain
& tf_error
)
4208 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4209 TREE_TYPE (expr
), type
);
4210 expr
= error_mark_node
;
4213 /* Free all the conversions we allocated. */
4214 obstack_free (&conversion_obstack
, p
);
4219 /* Do any initial processing on the arguments to a function call. */
4221 static vec
<tree
, va_gc
> *
4222 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4227 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4229 if (error_operand_p (arg
))
4231 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4233 if (complain
& tf_error
)
4234 error ("invalid use of void expression");
4237 else if (invalid_nonstatic_memfn_p (arg
->exp
.locus
, arg
, complain
))
4243 /* Perform overload resolution on FN, which is called with the ARGS.
4245 Return the candidate function selected by overload resolution, or
4246 NULL if the event that overload resolution failed. In the case
4247 that overload resolution fails, *CANDIDATES will be the set of
4248 candidates considered, and ANY_VIABLE_P will be set to true or
4249 false to indicate whether or not any of the candidates were
4252 The ARGS should already have gone through RESOLVE_ARGS before this
4253 function is called. */
4255 static struct z_candidate
*
4256 perform_overload_resolution (tree fn
,
4257 const vec
<tree
, va_gc
> *args
,
4258 struct z_candidate
**candidates
,
4259 bool *any_viable_p
, tsubst_flags_t complain
)
4261 struct z_candidate
*cand
;
4262 tree explicit_targs
;
4265 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4267 explicit_targs
= NULL_TREE
;
4271 *any_viable_p
= true;
4274 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4275 || TREE_CODE (fn
) == TEMPLATE_DECL
4276 || TREE_CODE (fn
) == OVERLOAD
4277 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4279 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4281 explicit_targs
= TREE_OPERAND (fn
, 1);
4282 fn
= TREE_OPERAND (fn
, 0);
4286 /* Add the various candidate functions. */
4287 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4288 explicit_targs
, template_only
,
4289 /*conversion_path=*/NULL_TREE
,
4290 /*access_path=*/NULL_TREE
,
4292 candidates
, complain
);
4294 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4296 cand
= tourney (*candidates
, complain
);
4300 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4304 /* Print an error message about being unable to build a call to FN with
4305 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4306 be located; CANDIDATES is a possibly empty list of such
4310 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4311 struct z_candidate
*candidates
)
4313 tree targs
= NULL_TREE
;
4314 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4316 targs
= TREE_OPERAND (fn
, 1);
4317 fn
= TREE_OPERAND (fn
, 0);
4319 tree name
= OVL_NAME (fn
);
4320 location_t loc
= location_of (name
);
4322 name
= lookup_template_function (name
, targs
);
4324 auto_diagnostic_group d
;
4325 if (!any_strictly_viable (candidates
))
4326 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4327 name
, build_tree_list_vec (args
));
4329 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4330 name
, build_tree_list_vec (args
));
4332 print_z_candidates (loc
, candidates
);
4335 /* Return an expression for a call to FN (a namespace-scope function,
4336 or a static member function) with the ARGS. This may change
4340 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4341 tsubst_flags_t complain
)
4343 struct z_candidate
*candidates
, *cand
;
4348 if (args
!= NULL
&& *args
!= NULL
)
4350 *args
= resolve_args (*args
, complain
);
4352 return error_mark_node
;
4356 tm_malloc_replacement (fn
);
4358 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4359 p
= conversion_obstack_alloc (0);
4361 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4366 if (complain
& tf_error
)
4368 // If there is a single (non-viable) function candidate,
4369 // let the error be diagnosed by cp_build_function_call_vec.
4370 if (!any_viable_p
&& candidates
&& ! candidates
->next
4371 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4372 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4374 // Otherwise, emit notes for non-viable candidates.
4375 print_error_for_call_failure (fn
, *args
, candidates
);
4377 result
= error_mark_node
;
4381 int flags
= LOOKUP_NORMAL
;
4382 /* If fn is template_id_expr, the call has explicit template arguments
4383 (e.g. func<int>(5)), communicate this info to build_over_call
4384 through flags so that later we can use it to decide whether to warn
4385 about peculiar null pointer conversion. */
4386 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4388 /* If overload resolution selects a specialization of a
4389 function concept for non-dependent template arguments,
4390 the expression is true if the constraints are satisfied
4391 and false otherwise.
4393 NOTE: This is an extension of Concepts Lite TS that
4394 allows constraints to be used in expressions. */
4395 if (flag_concepts
&& !processing_template_decl
)
4397 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4398 tree targs
= DECL_TI_ARGS (cand
->fn
);
4399 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4400 if (DECL_DECLARED_CONCEPT_P (decl
))
4401 return evaluate_function_concept (decl
, targs
);
4404 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4407 result
= build_over_call (cand
, flags
, complain
);
4410 /* Free all the conversions we allocated. */
4411 obstack_free (&conversion_obstack
, p
);
4416 /* Build a call to a global operator new. FNNAME is the name of the
4417 operator (either "operator new" or "operator new[]") and ARGS are
4418 the arguments provided. This may change ARGS. *SIZE points to the
4419 total number of bytes required by the allocation, and is updated if
4420 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4421 be used. If this function determines that no cookie should be
4422 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4423 is not NULL_TREE, it is evaluated before calculating the final
4424 array size, and if it fails, the array size is replaced with
4425 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4426 is non-NULL, it will be set, upon return, to the allocation
4430 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4431 tree
*size
, tree
*cookie_size
,
4432 tree align_arg
, tree size_check
,
4433 tree
*fn
, tsubst_flags_t complain
)
4435 tree original_size
= *size
;
4437 struct z_candidate
*candidates
;
4438 struct z_candidate
*cand
= NULL
;
4443 /* Set to (size_t)-1 if the size check fails. */
4444 if (size_check
!= NULL_TREE
)
4446 tree errval
= TYPE_MAX_VALUE (sizetype
);
4447 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4448 errval
= throw_bad_array_new_length ();
4449 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4450 original_size
, errval
);
4452 vec_safe_insert (*args
, 0, *size
);
4453 *args
= resolve_args (*args
, complain
);
4455 return error_mark_node
;
4461 If this lookup fails to find the name, or if the allocated type
4462 is not a class type, the allocation function's name is looked
4463 up in the global scope.
4465 we disregard block-scope declarations of "operator new". */
4466 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4467 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4471 vec
<tree
, va_gc
>* align_args
4472 = vec_copy_and_insert (*args
, align_arg
, 1);
4473 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4474 &any_viable_p
, tf_none
);
4477 /* If no aligned allocation function matches, try again without the
4481 /* Figure out what function is being called. */
4483 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4486 /* If no suitable function could be found, issue an error message
4490 if (complain
& tf_error
)
4491 print_error_for_call_failure (fns
, *args
, candidates
);
4492 return error_mark_node
;
4495 /* If a cookie is required, add some extra space. Whether
4496 or not a cookie is required cannot be determined until
4497 after we know which function was called. */
4500 bool use_cookie
= true;
4503 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4504 /* Skip the size_t parameter. */
4505 arg_types
= TREE_CHAIN (arg_types
);
4506 /* Check the remaining parameters (if any). */
4508 && TREE_CHAIN (arg_types
) == void_list_node
4509 && same_type_p (TREE_VALUE (arg_types
),
4512 /* If we need a cookie, adjust the number of bytes allocated. */
4515 /* Update the total size. */
4516 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4519 /* Set to (size_t)-1 if the size check fails. */
4520 gcc_assert (size_check
!= NULL_TREE
);
4521 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4522 *size
, TYPE_MAX_VALUE (sizetype
));
4524 /* Update the argument list to reflect the adjusted size. */
4525 (**args
)[0] = *size
;
4528 *cookie_size
= NULL_TREE
;
4531 /* Tell our caller which function we decided to call. */
4535 /* Build the CALL_EXPR. */
4536 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4539 /* Build a new call to operator(). This may change ARGS. */
4542 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4544 struct z_candidate
*candidates
= 0, *cand
;
4545 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4547 tree result
= NULL_TREE
;
4550 obj
= mark_lvalue_use (obj
);
4552 if (error_operand_p (obj
))
4553 return error_mark_node
;
4555 tree type
= TREE_TYPE (obj
);
4557 obj
= prep_operand (obj
);
4559 if (TYPE_PTRMEMFUNC_P (type
))
4561 if (complain
& tf_error
)
4562 /* It's no good looking for an overloaded operator() on a
4563 pointer-to-member-function. */
4564 error ("pointer-to-member function %qE cannot be called without "
4565 "an object; consider using %<.*%> or %<->*%>", obj
);
4566 return error_mark_node
;
4569 if (TYPE_BINFO (type
))
4571 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4572 if (fns
== error_mark_node
)
4573 return error_mark_node
;
4578 if (args
!= NULL
&& *args
!= NULL
)
4580 *args
= resolve_args (*args
, complain
);
4582 return error_mark_node
;
4585 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4586 p
= conversion_obstack_alloc (0);
4590 first_mem_arg
= obj
;
4592 add_candidates (BASELINK_FUNCTIONS (fns
),
4593 first_mem_arg
, *args
, NULL_TREE
,
4595 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4596 LOOKUP_NORMAL
, &candidates
, complain
);
4599 convs
= lookup_conversions (type
);
4601 for (; convs
; convs
= TREE_CHAIN (convs
))
4603 tree totype
= TREE_TYPE (convs
);
4605 if (TYPE_PTRFN_P (totype
)
4606 || TYPE_REFFN_P (totype
)
4607 || (TYPE_REF_P (totype
)
4608 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4609 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4613 if (DECL_NONCONVERTING_P (fn
))
4616 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4617 add_template_conv_candidate
4618 (&candidates
, fn
, obj
, *args
, totype
,
4619 /*access_path=*/NULL_TREE
,
4620 /*conversion_path=*/NULL_TREE
, complain
);
4622 add_conv_candidate (&candidates
, fn
, obj
,
4623 *args
, /*conversion_path=*/NULL_TREE
,
4624 /*access_path=*/NULL_TREE
, complain
);
4628 /* Be strict here because if we choose a bad conversion candidate, the
4629 errors we get won't mention the call context. */
4630 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4633 if (complain
& tf_error
)
4635 auto_diagnostic_group d
;
4636 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4637 build_tree_list_vec (*args
));
4638 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4640 result
= error_mark_node
;
4644 cand
= tourney (candidates
, complain
);
4647 if (complain
& tf_error
)
4649 auto_diagnostic_group d
;
4650 error ("call of %<(%T) (%A)%> is ambiguous",
4651 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4652 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4654 result
= error_mark_node
;
4656 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4657 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4658 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4659 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4662 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4663 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4667 gcc_checking_assert (TYPE_P (cand
->fn
));
4668 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4670 obj
= convert_from_reference (obj
);
4671 result
= cp_build_function_call_vec (obj
, args
, complain
);
4675 /* Free all the conversions we allocated. */
4676 obstack_free (&conversion_obstack
, p
);
4681 /* Wrapper for above. */
4684 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4687 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4688 ret
= build_op_call_1 (obj
, args
, complain
);
4689 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4693 /* Called by op_error to prepare format strings suitable for the error
4694 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4695 and a suffix (controlled by NTYPES). */
4698 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4702 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4703 : G_("no match for "), errmsg
, NULL
);
4706 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4707 else if (ntypes
== 2)
4708 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4710 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4716 op_error (const op_location_t
&loc
,
4717 enum tree_code code
, enum tree_code code2
,
4718 tree arg1
, tree arg2
, tree arg3
, bool match
)
4720 bool assop
= code
== MODIFY_EXPR
;
4721 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4726 if (flag_diagnostics_show_caret
)
4727 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4729 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4731 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4732 "in %<%E ? %E : %E%>"), 3, match
),
4734 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4737 case POSTINCREMENT_EXPR
:
4738 case POSTDECREMENT_EXPR
:
4739 if (flag_diagnostics_show_caret
)
4740 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4741 opname
, TREE_TYPE (arg1
));
4743 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4745 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4749 if (flag_diagnostics_show_caret
)
4750 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4751 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4753 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4755 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4760 if (flag_diagnostics_show_caret
)
4761 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4762 opname
, TREE_TYPE (arg1
));
4764 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4765 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4770 if (flag_diagnostics_show_caret
)
4772 binary_op_rich_location
richloc (loc
, arg1
, arg2
, true);
4774 op_error_string (G_("%<operator%s%>"), 2, match
),
4775 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4778 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4780 opname
, arg1
, opname
, arg2
,
4781 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4783 if (flag_diagnostics_show_caret
)
4784 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4785 opname
, TREE_TYPE (arg1
));
4787 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4789 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4794 /* Return the implicit conversion sequence that could be used to
4795 convert E1 to E2 in [expr.cond]. */
4798 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4800 tree t1
= non_reference (TREE_TYPE (e1
));
4801 tree t2
= non_reference (TREE_TYPE (e2
));
4807 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4808 implicitly converted (clause _conv_) to the type "lvalue reference to
4809 T2", subject to the constraint that in the conversion the
4810 reference must bind directly (_dcl.init.ref_) to an lvalue.
4812 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4813 implicitly converted to the type "rvalue reference to T2", subject to
4814 the constraint that the reference must bind directly. */
4817 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4818 conv
= implicit_conversion (rtype
,
4822 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4823 |LOOKUP_ONLYCONVERTING
,
4825 if (conv
&& !conv
->bad_p
)
4829 /* If E2 is a prvalue or if neither of the conversions above can be done
4830 and at least one of the operands has (possibly cv-qualified) class
4832 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4837 If E1 and E2 have class type, and the underlying class types are
4838 the same or one is a base class of the other: E1 can be converted
4839 to match E2 if the class of T2 is the same type as, or a base
4840 class of, the class of T1, and the cv-qualification of T2 is the
4841 same cv-qualification as, or a greater cv-qualification than, the
4842 cv-qualification of T1. If the conversion is applied, E1 is
4843 changed to an rvalue of type T2 that still refers to the original
4844 source class object (or the appropriate subobject thereof). */
4845 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4846 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4848 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4850 conv
= build_identity_conv (t1
, e1
);
4851 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4852 TYPE_MAIN_VARIANT (t2
)))
4853 conv
= build_conv (ck_base
, t2
, conv
);
4855 conv
= build_conv (ck_rvalue
, t2
, conv
);
4864 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4865 converted to the type that expression E2 would have if E2 were
4866 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4867 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4868 LOOKUP_IMPLICIT
, complain
);
4871 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4872 arguments to the conditional expression. */
4875 build_conditional_expr_1 (const op_location_t
&loc
,
4876 tree arg1
, tree arg2
, tree arg3
,
4877 tsubst_flags_t complain
)
4881 tree result
= NULL_TREE
;
4882 tree result_type
= NULL_TREE
;
4883 bool is_glvalue
= true;
4884 struct z_candidate
*candidates
= 0;
4885 struct z_candidate
*cand
;
4887 tree orig_arg2
, orig_arg3
;
4889 /* As a G++ extension, the second argument to the conditional can be
4890 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4891 c'.) If the second operand is omitted, make sure it is
4892 calculated only once. */
4895 if (complain
& tf_error
)
4896 pedwarn (loc
, OPT_Wpedantic
,
4897 "ISO C++ forbids omitting the middle term of a ?: expression");
4899 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
4900 warn_for_omitted_condop (loc
, arg1
);
4902 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4903 if (lvalue_p (arg1
))
4904 arg2
= arg1
= cp_stabilize_reference (arg1
);
4906 arg2
= arg1
= cp_save_expr (arg1
);
4909 /* If something has already gone wrong, just pass that fact up the
4911 if (error_operand_p (arg1
)
4912 || error_operand_p (arg2
)
4913 || error_operand_p (arg3
))
4914 return error_mark_node
;
4919 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
4921 tree arg1_type
= TREE_TYPE (arg1
);
4923 /* If arg1 is another cond_expr choosing between -1 and 0,
4924 then we can use its comparison. It may help to avoid
4925 additional comparison, produce more accurate diagnostics
4926 and enables folding. */
4927 if (TREE_CODE (arg1
) == VEC_COND_EXPR
4928 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
4929 && integer_zerop (TREE_OPERAND (arg1
, 2)))
4930 arg1
= TREE_OPERAND (arg1
, 0);
4932 arg1
= force_rvalue (arg1
, complain
);
4933 arg2
= force_rvalue (arg2
, complain
);
4934 arg3
= force_rvalue (arg3
, complain
);
4936 /* force_rvalue can return error_mark on valid arguments. */
4937 if (error_operand_p (arg1
)
4938 || error_operand_p (arg2
)
4939 || error_operand_p (arg3
))
4940 return error_mark_node
;
4942 arg2_type
= TREE_TYPE (arg2
);
4943 arg3_type
= TREE_TYPE (arg3
);
4945 if (!VECTOR_TYPE_P (arg2_type
)
4946 && !VECTOR_TYPE_P (arg3_type
))
4948 /* Rely on the error messages of the scalar version. */
4949 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
4950 orig_arg2
, orig_arg3
, complain
);
4951 if (scal
== error_mark_node
)
4952 return error_mark_node
;
4953 tree stype
= TREE_TYPE (scal
);
4954 tree ctype
= TREE_TYPE (arg1_type
);
4955 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
4956 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
4958 if (complain
& tf_error
)
4959 error_at (loc
, "inferred scalar type %qT is not an integer or "
4960 "floating point type of the same size as %qT", stype
,
4961 COMPARISON_CLASS_P (arg1
)
4962 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
4964 return error_mark_node
;
4967 tree vtype
= build_opaque_vector_type (stype
,
4968 TYPE_VECTOR_SUBPARTS (arg1_type
));
4969 /* We could pass complain & tf_warning to unsafe_conversion_p,
4970 but the warnings (like Wsign-conversion) have already been
4971 given by the scalar build_conditional_expr_1. We still check
4972 unsafe_conversion_p to forbid truncating long long -> float. */
4973 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
4975 if (complain
& tf_error
)
4976 error_at (loc
, "conversion of scalar %qH to vector %qI "
4977 "involves truncation", arg2_type
, vtype
);
4978 return error_mark_node
;
4980 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
4982 if (complain
& tf_error
)
4983 error_at (loc
, "conversion of scalar %qH to vector %qI "
4984 "involves truncation", arg3_type
, vtype
);
4985 return error_mark_node
;
4988 arg2
= cp_convert (stype
, arg2
, complain
);
4989 arg2
= save_expr (arg2
);
4990 arg2
= build_vector_from_val (vtype
, arg2
);
4992 arg3
= cp_convert (stype
, arg3
, complain
);
4993 arg3
= save_expr (arg3
);
4994 arg3
= build_vector_from_val (vtype
, arg3
);
4998 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
5000 enum stv_conv convert_flag
=
5001 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
5002 complain
& tf_error
);
5004 switch (convert_flag
)
5007 return error_mark_node
;
5010 arg2
= save_expr (arg2
);
5011 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5012 arg2
= build_vector_from_val (arg3_type
, arg2
);
5013 arg2_type
= TREE_TYPE (arg2
);
5018 arg3
= save_expr (arg3
);
5019 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5020 arg3
= build_vector_from_val (arg2_type
, arg3
);
5021 arg3_type
= TREE_TYPE (arg3
);
5029 if (!same_type_p (arg2_type
, arg3_type
)
5030 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5031 TYPE_VECTOR_SUBPARTS (arg2_type
))
5032 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5034 if (complain
& tf_error
)
5036 "incompatible vector types in conditional expression: "
5037 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5038 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5039 return error_mark_node
;
5042 if (!COMPARISON_CLASS_P (arg1
))
5044 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5045 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5047 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5052 The first expression is implicitly converted to bool (clause
5054 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5056 if (error_operand_p (arg1
))
5057 return error_mark_node
;
5061 If either the second or the third operand has type (possibly
5062 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5063 array-to-pointer (_conv.array_), and function-to-pointer
5064 (_conv.func_) standard conversions are performed on the second
5065 and third operands. */
5066 arg2_type
= unlowered_expr_type (arg2
);
5067 arg3_type
= unlowered_expr_type (arg3
);
5068 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5072 One of the following shall hold:
5074 --The second or the third operand (but not both) is a
5075 throw-expression (_except.throw_); the result is of the type
5076 and value category of the other.
5078 --Both the second and the third operands have type void; the
5079 result is of type void and is a prvalue. */
5080 if (TREE_CODE (arg2
) == THROW_EXPR
5081 && TREE_CODE (arg3
) != THROW_EXPR
)
5083 result_type
= arg3_type
;
5084 is_glvalue
= glvalue_p (arg3
);
5086 else if (TREE_CODE (arg2
) != THROW_EXPR
5087 && TREE_CODE (arg3
) == THROW_EXPR
)
5089 result_type
= arg2_type
;
5090 is_glvalue
= glvalue_p (arg2
);
5092 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5094 result_type
= void_type_node
;
5099 if (complain
& tf_error
)
5101 if (VOID_TYPE_P (arg2_type
))
5102 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5103 "second operand to the conditional operator "
5104 "is of type %<void%>, but the third operand is "
5105 "neither a throw-expression nor of type %<void%>");
5107 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5108 "third operand to the conditional operator "
5109 "is of type %<void%>, but the second operand is "
5110 "neither a throw-expression nor of type %<void%>");
5112 return error_mark_node
;
5115 goto valid_operands
;
5119 Otherwise, if the second and third operand have different types,
5120 and either has (possibly cv-qualified) class type, or if both are
5121 glvalues of the same value category and the same type except for
5122 cv-qualification, an attempt is made to convert each of those operands
5123 to the type of the other. */
5124 else if (!same_type_p (arg2_type
, arg3_type
)
5125 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5126 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5128 && glvalue_p (arg2
) && glvalue_p (arg3
)
5129 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5133 bool converted
= false;
5135 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5136 p
= conversion_obstack_alloc (0);
5138 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5139 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5143 If both can be converted, or one can be converted but the
5144 conversion is ambiguous, the program is ill-formed. If
5145 neither can be converted, the operands are left unchanged and
5146 further checking is performed as described below. If exactly
5147 one conversion is possible, that conversion is applied to the
5148 chosen operand and the converted operand is used in place of
5149 the original operand for the remainder of this section. */
5150 if ((conv2
&& !conv2
->bad_p
5151 && conv3
&& !conv3
->bad_p
)
5152 || (conv2
&& conv2
->kind
== ck_ambig
)
5153 || (conv3
&& conv3
->kind
== ck_ambig
))
5155 if (complain
& tf_error
)
5157 error_at (loc
, "operands to ?: have different types %qT and %qT",
5158 arg2_type
, arg3_type
);
5159 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5160 inform (loc
, " and each type can be converted to the other");
5161 else if (conv2
&& conv2
->kind
== ck_ambig
)
5162 convert_like (conv2
, arg2
, complain
);
5164 convert_like (conv3
, arg3
, complain
);
5166 result
= error_mark_node
;
5168 else if (conv2
&& !conv2
->bad_p
)
5170 arg2
= convert_like (conv2
, arg2
, complain
);
5171 arg2
= convert_from_reference (arg2
);
5172 arg2_type
= TREE_TYPE (arg2
);
5173 /* Even if CONV2 is a valid conversion, the result of the
5174 conversion may be invalid. For example, if ARG3 has type
5175 "volatile X", and X does not have a copy constructor
5176 accepting a "volatile X&", then even if ARG2 can be
5177 converted to X, the conversion will fail. */
5178 if (error_operand_p (arg2
))
5179 result
= error_mark_node
;
5182 else if (conv3
&& !conv3
->bad_p
)
5184 arg3
= convert_like (conv3
, arg3
, complain
);
5185 arg3
= convert_from_reference (arg3
);
5186 arg3_type
= TREE_TYPE (arg3
);
5187 if (error_operand_p (arg3
))
5188 result
= error_mark_node
;
5192 /* Free all the conversions we allocated. */
5193 obstack_free (&conversion_obstack
, p
);
5198 /* If, after the conversion, both operands have class type,
5199 treat the cv-qualification of both operands as if it were the
5200 union of the cv-qualification of the operands.
5202 The standard is not clear about what to do in this
5203 circumstance. For example, if the first operand has type
5204 "const X" and the second operand has a user-defined
5205 conversion to "volatile X", what is the type of the second
5206 operand after this step? Making it be "const X" (matching
5207 the first operand) seems wrong, as that discards the
5208 qualification without actually performing a copy. Leaving it
5209 as "volatile X" seems wrong as that will result in the
5210 conditional expression failing altogether, even though,
5211 according to this step, the one operand could be converted to
5212 the type of the other. */
5214 && CLASS_TYPE_P (arg2_type
)
5215 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5216 arg2_type
= arg3_type
=
5217 cp_build_qualified_type (arg2_type
,
5218 cp_type_quals (arg2_type
)
5219 | cp_type_quals (arg3_type
));
5224 If the second and third operands are glvalues of the same value
5225 category and have the same type, the result is of that type and
5227 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5228 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5229 && same_type_p (arg2_type
, arg3_type
))
5231 result_type
= arg2_type
;
5232 arg2
= mark_lvalue_use (arg2
);
5233 arg3
= mark_lvalue_use (arg3
);
5234 goto valid_operands
;
5239 Otherwise, the result is an rvalue. If the second and third
5240 operand do not have the same type, and either has (possibly
5241 cv-qualified) class type, overload resolution is used to
5242 determine the conversions (if any) to be applied to the operands
5243 (_over.match.oper_, _over.built_). */
5245 if (!same_type_p (arg2_type
, arg3_type
)
5246 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5252 /* Rearrange the arguments so that add_builtin_candidate only has
5253 to know about two args. In build_builtin_candidate, the
5254 arguments are unscrambled. */
5258 add_builtin_candidates (&candidates
,
5261 ovl_op_identifier (false, COND_EXPR
),
5263 LOOKUP_NORMAL
, complain
);
5267 If the overload resolution fails, the program is
5269 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5272 if (complain
& tf_error
)
5273 error_at (loc
, "operands to ?: have different types %qT and %qT",
5274 arg2_type
, arg3_type
);
5275 return error_mark_node
;
5277 cand
= tourney (candidates
, complain
);
5280 if (complain
& tf_error
)
5282 auto_diagnostic_group d
;
5283 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5284 print_z_candidates (loc
, candidates
);
5286 return error_mark_node
;
5291 Otherwise, the conversions thus determined are applied, and
5292 the converted operands are used in place of the original
5293 operands for the remainder of this section. */
5294 conv
= cand
->convs
[0];
5295 arg1
= convert_like (conv
, arg1
, complain
);
5296 conv
= cand
->convs
[1];
5297 arg2
= convert_like (conv
, arg2
, complain
);
5298 arg2_type
= TREE_TYPE (arg2
);
5299 conv
= cand
->convs
[2];
5300 arg3
= convert_like (conv
, arg3
, complain
);
5301 arg3_type
= TREE_TYPE (arg3
);
5306 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5307 and function-to-pointer (_conv.func_) standard conversions are
5308 performed on the second and third operands.
5310 We need to force the lvalue-to-rvalue conversion here for class types,
5311 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5312 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5315 arg2
= force_rvalue (arg2
, complain
);
5316 if (!CLASS_TYPE_P (arg2_type
))
5317 arg2_type
= TREE_TYPE (arg2
);
5319 arg3
= force_rvalue (arg3
, complain
);
5320 if (!CLASS_TYPE_P (arg3_type
))
5321 arg3_type
= TREE_TYPE (arg3
);
5323 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5324 return error_mark_node
;
5328 After those conversions, one of the following shall hold:
5330 --The second and third operands have the same type; the result is of
5332 if (same_type_p (arg2_type
, arg3_type
))
5333 result_type
= arg2_type
;
5336 --The second and third operands have arithmetic or enumeration
5337 type; the usual arithmetic conversions are performed to bring
5338 them to a common type, and the result is of that type. */
5339 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5340 || UNSCOPED_ENUM_P (arg2_type
))
5341 && (ARITHMETIC_TYPE_P (arg3_type
)
5342 || UNSCOPED_ENUM_P (arg3_type
)))
5344 /* In this case, there is always a common type. */
5345 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5347 if (complain
& tf_warning
)
5348 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5349 "implicit conversion from %qH to %qI to "
5350 "match other result of conditional",
5353 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5354 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5356 tree stripped_orig_arg2
= tree_strip_any_location_wrapper (orig_arg2
);
5357 tree stripped_orig_arg3
= tree_strip_any_location_wrapper (orig_arg3
);
5358 if (TREE_CODE (stripped_orig_arg2
) == CONST_DECL
5359 && TREE_CODE (stripped_orig_arg3
) == CONST_DECL
5360 && (DECL_CONTEXT (stripped_orig_arg2
)
5361 == DECL_CONTEXT (stripped_orig_arg3
)))
5362 /* Two enumerators from the same enumeration can have different
5363 types when the enumeration is still being defined. */;
5364 else if (complain
& tf_warning
)
5365 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5366 "conditional expression: %qT vs %qT",
5367 arg2_type
, arg3_type
);
5369 else if (extra_warnings
5370 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5371 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5372 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5373 && !same_type_p (arg2_type
,
5374 type_promotes_to (arg3_type
)))))
5376 if (complain
& tf_warning
)
5377 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5378 "conditional expression");
5381 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5382 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5386 --The second and third operands have pointer type, or one has
5387 pointer type and the other is a null pointer constant; pointer
5388 conversions (_conv.ptr_) and qualification conversions
5389 (_conv.qual_) are performed to bring them to their composite
5390 pointer type (_expr.rel_). The result is of the composite
5393 --The second and third operands have pointer to member type, or
5394 one has pointer to member type and the other is a null pointer
5395 constant; pointer to member conversions (_conv.mem_) and
5396 qualification conversions (_conv.qual_) are performed to bring
5397 them to a common type, whose cv-qualification shall match the
5398 cv-qualification of either the second or the third operand.
5399 The result is of the common type. */
5400 else if ((null_ptr_cst_p (arg2
)
5401 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5402 || (null_ptr_cst_p (arg3
)
5403 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5404 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5405 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5406 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5408 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5409 arg3
, CPO_CONDITIONAL_EXPR
,
5411 if (result_type
== error_mark_node
)
5412 return error_mark_node
;
5413 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5414 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5419 if (complain
& tf_error
)
5420 error_at (loc
, "operands to ?: have different types %qT and %qT",
5421 arg2_type
, arg3_type
);
5422 return error_mark_node
;
5425 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5426 return error_mark_node
;
5429 if (processing_template_decl
&& is_glvalue
)
5431 /* Let lvalue_kind know this was a glvalue. */
5432 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5433 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5436 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5438 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5439 warn here, because the COND_EXPR will be turned into ARG2. */
5440 if (warn_duplicated_branches
5441 && (complain
& tf_warning
)
5442 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5443 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5444 "this condition has identical branches");
5446 /* We can't use result_type below, as fold might have returned a
5451 /* Expand both sides into the same slot, hopefully the target of
5452 the ?: expression. We used to check for TARGET_EXPRs here,
5453 but now we sometimes wrap them in NOP_EXPRs so the test would
5455 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5456 result
= get_target_expr_sfinae (result
, complain
);
5457 /* If this expression is an rvalue, but might be mistaken for an
5458 lvalue, we must add a NON_LVALUE_EXPR. */
5459 result
= rvalue (result
);
5462 result
= force_paren_expr (result
);
5467 /* Wrapper for above. */
5470 build_conditional_expr (const op_location_t
&loc
,
5471 tree arg1
, tree arg2
, tree arg3
,
5472 tsubst_flags_t complain
)
5475 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5476 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5477 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5481 /* OPERAND is an operand to an expression. Perform necessary steps
5482 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5486 prep_operand (tree operand
)
5490 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5491 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5492 /* Make sure the template type is instantiated now. */
5493 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5499 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5500 OVERLOAD) to the CANDIDATES, returning an updated list of
5501 CANDIDATES. The ARGS are the arguments provided to the call;
5502 if FIRST_ARG is non-null it is the implicit object argument,
5503 otherwise the first element of ARGS is used if needed. The
5504 EXPLICIT_TARGS are explicit template arguments provided.
5505 TEMPLATE_ONLY is true if only template functions should be
5506 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5507 add_function_candidate. */
5510 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5512 tree explicit_targs
, bool template_only
,
5513 tree conversion_path
, tree access_path
,
5515 struct z_candidate
**candidates
,
5516 tsubst_flags_t complain
)
5519 const vec
<tree
, va_gc
> *non_static_args
;
5520 bool check_list_ctor
= false;
5521 bool check_converting
= false;
5522 unification_kind_t strict
;
5527 /* Precalculate special handling of constructors and conversion ops. */
5528 tree fn
= OVL_FIRST (fns
);
5529 if (DECL_CONV_FN_P (fn
))
5531 check_list_ctor
= false;
5532 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5533 if (flags
& LOOKUP_NO_CONVERSION
)
5534 /* We're doing return_type(x). */
5535 strict
= DEDUCE_CONV
;
5537 /* We're doing x.operator return_type(). */
5538 strict
= DEDUCE_EXACT
;
5539 /* [over.match.funcs] For conversion functions, the function
5540 is considered to be a member of the class of the implicit
5541 object argument for the purpose of defining the type of
5542 the implicit object parameter. */
5543 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5547 if (DECL_CONSTRUCTOR_P (fn
))
5549 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5550 /* For list-initialization we consider explicit constructors
5551 and complain if one is chosen. */
5553 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5554 == LOOKUP_ONLYCONVERTING
);
5556 strict
= DEDUCE_CALL
;
5557 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5561 non_static_args
= args
;
5563 /* Delay creating the implicit this parameter until it is needed. */
5564 non_static_args
= NULL
;
5566 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5570 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5572 if (check_list_ctor
&& !is_list_ctor (fn
))
5575 tree fn_first_arg
= NULL_TREE
;
5576 const vec
<tree
, va_gc
> *fn_args
= args
;
5578 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5580 /* Figure out where the object arg comes from. If this
5581 function is a non-static member and we didn't get an
5582 implicit object argument, move it out of args. */
5583 if (first_arg
== NULL_TREE
)
5587 vec
<tree
, va_gc
> *tempvec
;
5588 vec_alloc (tempvec
, args
->length () - 1);
5589 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5590 tempvec
->quick_push (arg
);
5591 non_static_args
= tempvec
;
5592 first_arg
= (*args
)[0];
5595 fn_first_arg
= first_arg
;
5596 fn_args
= non_static_args
;
5599 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5600 add_template_candidate (candidates
,
5612 else if (!template_only
)
5613 add_function_candidate (candidates
,
5626 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5627 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5630 op_is_ordered (tree_code code
)
5636 return (flag_strong_eval_order
> 1 ? -1 : 0);
5640 return (flag_strong_eval_order
> 1 ? 1 : 0);
5643 // Not overloadable (yet).
5645 // Only one argument.
5652 return (flag_strong_eval_order
? 1 : 0);
5660 build_new_op_1 (const op_location_t
&loc
, enum tree_code code
, int flags
,
5661 tree arg1
, tree arg2
, tree arg3
, tree
*overload
,
5662 tsubst_flags_t complain
)
5664 struct z_candidate
*candidates
= 0, *cand
;
5665 vec
<tree
, va_gc
> *arglist
;
5667 tree result
= NULL_TREE
;
5668 bool result_valid_p
= false;
5669 enum tree_code code2
= NOP_EXPR
;
5670 enum tree_code code_orig_arg1
= ERROR_MARK
;
5671 enum tree_code code_orig_arg2
= ERROR_MARK
;
5677 if (error_operand_p (arg1
)
5678 || error_operand_p (arg2
)
5679 || error_operand_p (arg3
))
5680 return error_mark_node
;
5682 bool ismodop
= code
== MODIFY_EXPR
;
5685 code2
= TREE_CODE (arg3
);
5688 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5690 arg1
= prep_operand (arg1
);
5692 bool memonly
= false;
5697 case VEC_DELETE_EXPR
:
5699 /* Use build_op_new_call and build_op_delete_call instead. */
5703 /* Use build_op_call instead. */
5706 case TRUTH_ORIF_EXPR
:
5707 case TRUTH_ANDIF_EXPR
:
5708 case TRUTH_AND_EXPR
:
5710 /* These are saved for the sake of warn_logical_operator. */
5711 code_orig_arg1
= TREE_CODE (arg1
);
5712 code_orig_arg2
= TREE_CODE (arg2
);
5720 /* These are saved for the sake of maybe_warn_bool_compare. */
5721 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5722 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5725 /* =, ->, [], () must be non-static member functions. */
5727 if (code2
!= NOP_EXPR
)
5739 arg2
= prep_operand (arg2
);
5740 arg3
= prep_operand (arg3
);
5742 if (code
== COND_EXPR
)
5743 /* Use build_conditional_expr instead. */
5745 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5746 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5749 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5750 arg2
= integer_zero_node
;
5752 vec_alloc (arglist
, 3);
5753 arglist
->quick_push (arg1
);
5754 if (arg2
!= NULL_TREE
)
5755 arglist
->quick_push (arg2
);
5756 if (arg3
!= NULL_TREE
)
5757 arglist
->quick_push (arg3
);
5759 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5760 p
= conversion_obstack_alloc (0);
5762 /* Add namespace-scope operators to the list of functions to
5766 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5767 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5768 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5769 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5770 flags
, &candidates
, complain
);
5775 args
[2] = NULL_TREE
;
5777 /* Add class-member operators to the candidate set. */
5778 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5782 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5783 if (fns
== error_mark_node
)
5785 result
= error_mark_node
;
5786 goto user_defined_result_ready
;
5789 add_candidates (BASELINK_FUNCTIONS (fns
),
5790 NULL_TREE
, arglist
, NULL_TREE
,
5792 BASELINK_BINFO (fns
),
5793 BASELINK_ACCESS_BINFO (fns
),
5794 flags
, &candidates
, complain
);
5796 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5797 only non-member functions that have type T1 or reference to
5798 cv-qualified-opt T1 for the first argument, if the first argument
5799 has an enumeration type, or T2 or reference to cv-qualified-opt
5800 T2 for the second argument, if the second argument has an
5801 enumeration type. Filter out those that don't match. */
5802 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5804 struct z_candidate
**candp
, **next
;
5806 for (candp
= &candidates
; *candp
; candp
= next
)
5808 tree parmlist
, parmtype
;
5809 int i
, nargs
= (arg2
? 2 : 1);
5814 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5816 for (i
= 0; i
< nargs
; ++i
)
5818 parmtype
= TREE_VALUE (parmlist
);
5820 if (TYPE_REF_P (parmtype
))
5821 parmtype
= TREE_TYPE (parmtype
);
5822 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5823 && (same_type_ignoring_top_level_qualifiers_p
5824 (TREE_TYPE (args
[i
]), parmtype
)))
5827 parmlist
= TREE_CHAIN (parmlist
);
5830 /* No argument has an appropriate type, so remove this
5831 candidate function from the list. */
5834 *candp
= cand
->next
;
5840 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5847 /* For these, the built-in candidates set is empty
5848 [over.match.oper]/3. We don't want non-strict matches
5849 because exact matches are always possible with built-in
5850 operators. The built-in candidate set for COMPONENT_REF
5851 would be empty too, but since there are no such built-in
5852 operators, we accept non-strict matches for them. */
5861 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5866 case POSTINCREMENT_EXPR
:
5867 case POSTDECREMENT_EXPR
:
5868 /* Don't try anything fancy if we're not allowed to produce
5870 if (!(complain
& tf_error
))
5871 return error_mark_node
;
5873 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5874 distinguish between prefix and postfix ++ and
5875 operator++() was used for both, so we allow this with
5879 const char *msg
= (flag_permissive
)
5880 ? G_("no %<%D(int)%> declared for postfix %qs,"
5881 " trying prefix operator instead")
5882 : G_("no %<%D(int)%> declared for postfix %qs");
5883 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
5886 if (!flag_permissive
)
5887 return error_mark_node
;
5889 if (code
== POSTINCREMENT_EXPR
)
5890 code
= PREINCREMENT_EXPR
;
5892 code
= PREDECREMENT_EXPR
;
5893 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5894 NULL_TREE
, overload
, complain
);
5897 /* The caller will deal with these. */
5902 result_valid_p
= true;
5906 if (complain
& tf_error
)
5908 /* If one of the arguments of the operator represents
5909 an invalid use of member function pointer, try to report
5910 a meaningful error ... */
5911 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
5912 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
5913 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
5914 /* We displayed the error message. */;
5917 /* ... Otherwise, report the more generic
5918 "no matching operator found" error */
5919 auto_diagnostic_group d
;
5920 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
5921 print_z_candidates (loc
, candidates
);
5924 result
= error_mark_node
;
5930 cand
= tourney (candidates
, complain
);
5933 if (complain
& tf_error
)
5935 auto_diagnostic_group d
;
5936 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
5937 print_z_candidates (loc
, candidates
);
5939 result
= error_mark_node
;
5941 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
5944 *overload
= cand
->fn
;
5946 if (resolve_args (arglist
, complain
) == NULL
)
5947 result
= error_mark_node
;
5949 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
5951 if (trivial_fn_p (cand
->fn
))
5952 /* There won't be a CALL_EXPR. */;
5953 else if (result
&& result
!= error_mark_node
)
5955 tree call
= extract_call_expr (result
);
5956 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
5958 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
5959 /* This prevents build_new_function_call from discarding this
5960 function during instantiation of the enclosing template. */
5961 KOENIG_LOOKUP_P (call
) = 1;
5963 /* Specify evaluation order as per P0145R2. */
5964 CALL_EXPR_ORDERED_ARGS (call
) = false;
5965 switch (op_is_ordered (code
))
5968 CALL_EXPR_REVERSE_ARGS (call
) = true;
5972 CALL_EXPR_ORDERED_ARGS (call
) = true;
5982 /* Give any warnings we noticed during overload resolution. */
5983 if (cand
->warnings
&& (complain
& tf_warning
))
5985 struct candidate_warning
*w
;
5986 for (w
= cand
->warnings
; w
; w
= w
->next
)
5987 joust (cand
, w
->loser
, 1, complain
);
5990 /* Check for comparison of different enum types. */
5999 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
6000 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
6001 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
6002 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
6003 && (complain
& tf_warning
))
6005 warning (OPT_Wenum_compare
,
6006 "comparison between %q#T and %q#T",
6007 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
6014 /* We need to strip any leading REF_BIND so that bitfields
6015 don't cause errors. This should not remove any important
6016 conversions, because builtins don't apply to class
6017 objects directly. */
6018 conv
= cand
->convs
[0];
6019 if (conv
->kind
== ck_ref_bind
)
6020 conv
= next_conversion (conv
);
6021 arg1
= convert_like (conv
, arg1
, complain
);
6025 conv
= cand
->convs
[1];
6026 if (conv
->kind
== ck_ref_bind
)
6027 conv
= next_conversion (conv
);
6029 arg2
= decay_conversion (arg2
, complain
);
6031 /* We need to call warn_logical_operator before
6032 converting arg2 to a boolean_type, but after
6033 decaying an enumerator to its value. */
6034 if (complain
& tf_warning
)
6035 warn_logical_operator (loc
, code
, boolean_type_node
,
6036 code_orig_arg1
, arg1
,
6037 code_orig_arg2
, arg2
);
6039 arg2
= convert_like (conv
, arg2
, complain
);
6043 conv
= cand
->convs
[2];
6044 if (conv
->kind
== ck_ref_bind
)
6045 conv
= next_conversion (conv
);
6046 arg3
= convert_like (conv
, arg3
, complain
);
6052 user_defined_result_ready
:
6054 /* Free all the conversions we allocated. */
6055 obstack_free (&conversion_obstack
, p
);
6057 if (result
|| result_valid_p
)
6064 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6067 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6069 case TRUTH_ANDIF_EXPR
:
6070 case TRUTH_ORIF_EXPR
:
6071 case TRUTH_AND_EXPR
:
6073 if (complain
& tf_warning
)
6074 warn_logical_operator (loc
, code
, boolean_type_node
,
6075 code_orig_arg1
, arg1
,
6076 code_orig_arg2
, arg2
);
6084 if ((complain
& tf_warning
)
6085 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6086 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6087 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6088 if (complain
& tf_warning
&& warn_tautological_compare
)
6089 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6094 case TRUNC_DIV_EXPR
:
6099 case TRUNC_MOD_EXPR
:
6103 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6105 case UNARY_PLUS_EXPR
:
6108 case TRUTH_NOT_EXPR
:
6109 case PREINCREMENT_EXPR
:
6110 case POSTINCREMENT_EXPR
:
6111 case PREDECREMENT_EXPR
:
6112 case POSTDECREMENT_EXPR
:
6116 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6119 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6122 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6126 /* The caller will deal with these. */
6138 /* Wrapper for above. */
6141 build_new_op (const op_location_t
&loc
, enum tree_code code
, int flags
,
6142 tree arg1
, tree arg2
, tree arg3
,
6143 tree
*overload
, tsubst_flags_t complain
)
6146 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6147 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6148 overload
, complain
);
6149 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6153 /* CALL was returned by some call-building function; extract the actual
6154 CALL_EXPR from any bits that have been tacked on, e.g. by
6155 convert_from_reference. */
6158 extract_call_expr (tree call
)
6160 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6161 call
= TREE_OPERAND (call
, 1);
6162 if (REFERENCE_REF_P (call
))
6163 call
= TREE_OPERAND (call
, 0);
6164 if (TREE_CODE (call
) == TARGET_EXPR
)
6165 call
= TARGET_EXPR_INITIAL (call
);
6166 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6167 || TREE_CODE (call
) == AGGR_INIT_EXPR
6168 || call
== error_mark_node
);
6172 /* Returns true if FN has two parameters, of which the second has type
6176 second_parm_is_size_t (tree fn
)
6178 tree t
= FUNCTION_ARG_CHAIN (fn
);
6179 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6182 if (t
== void_list_node
)
6184 if (aligned_new_threshold
&& t
6185 && same_type_p (TREE_VALUE (t
), align_type_node
)
6186 && TREE_CHAIN (t
) == void_list_node
)
6191 /* True if T, an allocation function, has std::align_val_t as its second
6195 aligned_allocation_fn_p (tree t
)
6197 if (!aligned_new_threshold
)
6200 tree a
= FUNCTION_ARG_CHAIN (t
);
6201 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6204 /* True if T is std::destroying_delete_t. */
6207 std_destroying_delete_t_p (tree t
)
6209 return (TYPE_CONTEXT (t
) == std_node
6210 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6213 /* A deallocation function with at least two parameters whose second parameter
6214 type is of type std::destroying_delete_t is a destroying operator delete. A
6215 destroying operator delete shall be a class member function named operator
6216 delete. [ Note: Array deletion cannot use a destroying operator
6217 delete. --end note ] */
6220 destroying_delete_p (tree t
)
6222 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6223 if (!a
|| !TREE_CHAIN (a
))
6225 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6226 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6229 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6230 function (3.7.4.2 [basic.stc.dynamic.deallocation]) with a parameter of
6231 std::align_val_t. */
6234 aligned_deallocation_fn_p (tree t
)
6236 if (!aligned_new_threshold
)
6239 /* A template instance is never a usual deallocation function,
6240 regardless of its signature. */
6241 if (TREE_CODE (t
) == TEMPLATE_DECL
6242 || primary_template_specialization_p (t
))
6245 tree a
= FUNCTION_ARG_CHAIN (t
);
6246 if (destroying_delete_p (t
))
6248 if (same_type_p (TREE_VALUE (a
), align_type_node
)
6249 && TREE_CHAIN (a
) == void_list_node
)
6251 if (!same_type_p (TREE_VALUE (a
), size_type_node
))
6254 if (a
&& same_type_p (TREE_VALUE (a
), align_type_node
)
6255 && TREE_CHAIN (a
) == void_list_node
)
6260 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
6261 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
6264 usual_deallocation_fn_p (tree t
)
6266 /* A template instance is never a usual deallocation function,
6267 regardless of its signature. */
6268 if (TREE_CODE (t
) == TEMPLATE_DECL
6269 || primary_template_specialization_p (t
))
6272 /* If a class T has a member deallocation function named operator delete
6273 with exactly one parameter, then that function is a usual
6274 (non-placement) deallocation function. If class T does not declare
6275 such an operator delete but does declare a member deallocation
6276 function named operator delete with exactly two parameters, the second
6277 of which has type std::size_t (18.2), then this function is a usual
6278 deallocation function. */
6279 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6280 tree chain
= FUNCTION_ARG_CHAIN (t
);
6283 if (destroying_delete_p (t
))
6284 chain
= TREE_CHAIN (chain
);
6285 if (chain
== void_list_node
6286 || ((!global
|| flag_sized_deallocation
)
6287 && second_parm_is_size_t (t
)))
6289 if (aligned_deallocation_fn_p (t
))
6294 /* Build a call to operator delete. This has to be handled very specially,
6295 because the restrictions on what signatures match are different from all
6296 other call instances. For a normal delete, only a delete taking (void *)
6297 or (void *, size_t) is accepted. For a placement delete, only an exact
6298 match with the placement new is accepted.
6300 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6301 ADDR is the pointer to be deleted.
6302 SIZE is the size of the memory block to be deleted.
6303 GLOBAL_P is true if the delete-expression should not consider
6304 class-specific delete operators.
6305 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6307 If this call to "operator delete" is being generated as part to
6308 deallocate memory allocated via a new-expression (as per [expr.new]
6309 which requires that if the initialization throws an exception then
6310 we call a deallocation function), then ALLOC_FN is the allocation
6314 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6315 bool global_p
, tree placement
,
6316 tree alloc_fn
, tsubst_flags_t complain
)
6318 tree fn
= NULL_TREE
;
6319 tree fns
, fnname
, type
, t
;
6321 if (addr
== error_mark_node
)
6322 return error_mark_node
;
6324 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6326 fnname
= ovl_op_identifier (false, code
);
6328 if (CLASS_TYPE_P (type
)
6329 && COMPLETE_TYPE_P (complete_type (type
))
6333 If the result of the lookup is ambiguous or inaccessible, or if
6334 the lookup selects a placement deallocation function, the
6335 program is ill-formed.
6337 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6339 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6340 if (fns
== error_mark_node
)
6341 return error_mark_node
;
6346 if (fns
== NULL_TREE
)
6347 fns
= lookup_name_nonclass (fnname
);
6349 /* Strip const and volatile from addr. */
6351 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6355 /* "A declaration of a placement deallocation function matches the
6356 declaration of a placement allocation function if it has the same
6357 number of parameters and, after parameter transformations (8.3.5),
6358 all parameter types except the first are identical."
6360 So we build up the function type we want and ask instantiate_type
6361 to get it for us. */
6362 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6363 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6364 t
= build_function_type (void_type_node
, t
);
6366 fn
= instantiate_type (t
, fns
, tf_none
);
6367 if (fn
== error_mark_node
)
6370 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6372 /* "If the lookup finds the two-parameter form of a usual deallocation
6373 function (3.7.4.2) and that function, considered as a placement
6374 deallocation function, would have been selected as a match for the
6375 allocation function, the program is ill-formed." */
6376 if (second_parm_is_size_t (fn
))
6378 const char *const msg1
6379 = G_("exception cleanup for this placement new selects "
6380 "non-placement operator delete");
6381 const char *const msg2
6382 = G_("%qD is a usual (non-placement) deallocation "
6383 "function in C++14 (or with -fsized-deallocation)");
6385 /* But if the class has an operator delete (void *), then that is
6386 the usual deallocation function, so we shouldn't complain
6387 about using the operator delete (void *, size_t). */
6388 if (DECL_CLASS_SCOPE_P (fn
))
6389 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6393 if (usual_deallocation_fn_p (elt
)
6394 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6397 /* Before C++14 a two-parameter global deallocation function is
6398 always a placement deallocation function, but warn if
6400 else if (!flag_sized_deallocation
)
6402 if (complain
& tf_warning
)
6404 auto_diagnostic_group d
;
6405 if (warning (OPT_Wc__14_compat
, msg1
))
6406 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6411 if (complain
& tf_warning_or_error
)
6413 auto_diagnostic_group d
;
6414 if (permerror (input_location
, msg1
))
6416 /* Only mention C++14 for namespace-scope delete. */
6417 if (DECL_NAMESPACE_SCOPE_P (fn
))
6418 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6420 inform (DECL_SOURCE_LOCATION (fn
),
6421 "%qD is a usual (non-placement) deallocation "
6426 return error_mark_node
;
6431 /* "Any non-placement deallocation function matches a non-placement
6432 allocation function. If the lookup finds a single matching
6433 deallocation function, that function will be called; otherwise, no
6434 deallocation function will be called." */
6435 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6438 if (usual_deallocation_fn_p (elt
))
6446 /* -- If the type has new-extended alignment, a function with a
6447 parameter of type std::align_val_t is preferred; otherwise a
6448 function without such a parameter is preferred. If exactly one
6449 preferred function is found, that function is selected and the
6450 selection process terminates. If more than one preferred
6451 function is found, all non-preferred functions are eliminated
6452 from further consideration. */
6453 if (aligned_new_threshold
)
6455 bool want_align
= type_has_new_extended_alignment (type
);
6456 bool fn_align
= aligned_deallocation_fn_p (fn
);
6457 bool elt_align
= aligned_deallocation_fn_p (elt
);
6459 if (elt_align
!= fn_align
)
6461 if (want_align
== elt_align
)
6467 /* -- If the deallocation functions have class scope, the one
6468 without a parameter of type std::size_t is selected. */
6470 if (DECL_CLASS_SCOPE_P (fn
))
6473 /* -- If the type is complete and if, for the second alternative
6474 (delete array) only, the operand is a pointer to a class type
6475 with a non-trivial destructor or a (possibly multi-dimensional)
6476 array thereof, the function with a parameter of type std::size_t
6479 -- Otherwise, it is unspecified whether a deallocation function
6480 with a parameter of type std::size_t is selected. */
6483 want_size
= COMPLETE_TYPE_P (type
);
6484 if (code
== VEC_DELETE_EXPR
6485 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6486 /* We need a cookie to determine the array size. */
6489 bool fn_size
= second_parm_is_size_t (fn
);
6490 bool elt_size
= second_parm_is_size_t (elt
);
6491 gcc_assert (fn_size
!= elt_size
);
6492 if (want_size
== elt_size
)
6497 /* If we have a matching function, call it. */
6500 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6502 /* If the FN is a member function, make sure that it is
6504 if (BASELINK_P (fns
))
6505 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6508 /* Core issue 901: It's ok to new a type with deleted delete. */
6509 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6514 /* The placement args might not be suitable for overload
6515 resolution at this point, so build the call directly. */
6516 int nargs
= call_expr_nargs (placement
);
6517 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6520 for (i
= 1; i
< nargs
; i
++)
6521 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6522 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6523 return error_mark_node
;
6524 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6528 tree destroying
= destroying_delete_p (fn
);
6531 /* Strip const and volatile from addr but retain the type of the
6533 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6534 rtype
= cv_unqualified (rtype
);
6535 rtype
= TYPE_POINTER_TO (rtype
);
6536 addr
= cp_convert (rtype
, oaddr
, complain
);
6537 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6542 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6543 args
->quick_push (addr
);
6545 args
->quick_push (destroying
);
6546 if (second_parm_is_size_t (fn
))
6547 args
->quick_push (size
);
6548 if (aligned_deallocation_fn_p (fn
))
6550 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6551 args
->quick_push (al
);
6553 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6554 release_tree_vector (args
);
6561 If no unambiguous matching deallocation function can be found,
6562 propagating the exception does not cause the object's memory to
6566 if ((complain
& tf_warning
)
6568 warning (0, "no corresponding deallocation function for %qD",
6573 if (complain
& tf_error
)
6574 error ("no suitable %<operator %s%> for %qT",
6575 OVL_OP_INFO (false, code
)->name
, type
);
6576 return error_mark_node
;
6579 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6582 If ISSUE_ERROR is true, then issue an error about the
6583 access, followed by a note showing the declaration.
6584 Otherwise, just show the note. */
6587 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6589 if (TREE_PRIVATE (decl
))
6592 error ("%q#D is private within this context", diag_decl
);
6593 inform (DECL_SOURCE_LOCATION (diag_decl
),
6594 "declared private here");
6596 else if (TREE_PROTECTED (decl
))
6599 error ("%q#D is protected within this context", diag_decl
);
6600 inform (DECL_SOURCE_LOCATION (diag_decl
),
6601 "declared protected here");
6606 error ("%q#D is inaccessible within this context", diag_decl
);
6607 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6611 /* If the current scope isn't allowed to access DECL along
6612 BASETYPE_PATH, give an error. The most derived class in
6613 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6614 the declaration to use in the error diagnostic. */
6617 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6618 tsubst_flags_t complain
, access_failure_info
*afi
)
6620 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6622 if (flag_new_inheriting_ctors
6623 && DECL_INHERITED_CTOR (decl
))
6625 /* 7.3.3/18: The additional constructors are accessible if they would be
6626 accessible when used to construct an object of the corresponding base
6628 decl
= strip_inheriting_ctors (decl
);
6629 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6630 ba_any
, NULL
, complain
);
6633 if (!accessible_p (basetype_path
, decl
, true))
6635 if (flag_new_inheriting_ctors
)
6636 diag_decl
= strip_inheriting_ctors (diag_decl
);
6637 if (complain
& tf_error
)
6638 complain_about_access (decl
, diag_decl
, true);
6640 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6647 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6648 bitwise or of LOOKUP_* values. If any errors are warnings are
6649 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6650 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6654 build_temp (tree expr
, tree type
, int flags
,
6655 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6658 vec
<tree
, va_gc
> *args
;
6660 *diagnostic_kind
= DK_UNSPECIFIED
;
6662 /* If the source is a packed field, calling the copy constructor will require
6663 binding the field to the reference parameter to the copy constructor, and
6664 we'll end up with an infinite loop. If we can use a bitwise copy, then
6666 if ((lvalue_kind (expr
) & clk_packed
)
6667 && CLASS_TYPE_P (TREE_TYPE (expr
))
6668 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6669 return get_target_expr_sfinae (expr
, complain
);
6671 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6672 args
= make_tree_vector_single (expr
);
6673 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6674 &args
, type
, flags
, complain
);
6675 release_tree_vector (args
);
6676 if (warningcount
+ werrorcount
> savew
)
6677 *diagnostic_kind
= DK_WARNING
;
6678 else if (errorcount
> savee
)
6679 *diagnostic_kind
= DK_ERROR
;
6683 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6684 Also handle a subset of zero as null warnings.
6685 EXPR is implicitly converted to type TOTYPE.
6686 FN and ARGNUM are used for diagnostics. */
6689 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6691 /* Issue warnings about peculiar, but valid, uses of NULL. */
6692 if (null_node_p (expr
) && TREE_CODE (totype
) != BOOLEAN_TYPE
6693 && ARITHMETIC_TYPE_P (totype
))
6695 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6696 loc
= expansion_point_location_if_in_system_header (loc
);
6699 auto_diagnostic_group d
;
6700 if (warning_at (loc
, OPT_Wconversion_null
,
6701 "passing NULL to non-pointer argument %P of %qD",
6703 inform (get_fndecl_argument_location (fn
, argnum
),
6707 warning_at (loc
, OPT_Wconversion_null
,
6708 "converting to non-pointer type %qT from NULL", totype
);
6711 /* Issue warnings if "false" is converted to a NULL pointer */
6712 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6713 && TYPE_PTR_P (totype
))
6715 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6718 auto_diagnostic_group d
;
6719 if (warning_at (loc
, OPT_Wconversion_null
,
6720 "converting %<false%> to pointer type for argument "
6721 "%P of %qD", argnum
, fn
))
6722 inform (get_fndecl_argument_location (fn
, argnum
),
6726 warning_at (loc
, OPT_Wconversion_null
,
6727 "converting %<false%> to pointer type %qT", totype
);
6729 /* Handle zero as null pointer warnings for cases other
6730 than EQ_EXPR and NE_EXPR */
6731 else if (null_ptr_cst_p (expr
) &&
6732 (TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
)))
6735 expansion_point_location_if_in_system_header (input_location
);
6736 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6740 /* We gave a diagnostic during a conversion. If this was in the second
6741 standard conversion sequence of a user-defined conversion sequence, say
6742 which user-defined conversion. */
6745 maybe_print_user_conv_context (conversion
*convs
)
6747 if (convs
->user_conv_p
)
6748 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6749 if (t
->kind
== ck_user
)
6751 print_z_candidate (0, " after user-defined conversion:",
6757 /* Locate the parameter with the given index within FNDECL.
6758 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6759 Return the location of the FNDECL itself if there are problems. */
6762 get_fndecl_argument_location (tree fndecl
, int argnum
)
6764 /* The locations of implicitly-declared functions are likely to be
6765 more meaningful than those of their parameters. */
6766 if (DECL_ARTIFICIAL (fndecl
))
6767 return DECL_SOURCE_LOCATION (fndecl
);
6772 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6773 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6774 i
< argnum
&& param
;
6775 i
++, param
= TREE_CHAIN (param
))
6778 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6779 return the location of FNDECL. */
6781 return DECL_SOURCE_LOCATION (fndecl
);
6783 return DECL_SOURCE_LOCATION (param
);
6786 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6787 within its declaration (or the fndecl itself if something went
6791 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6794 inform (get_fndecl_argument_location (fn
, argnum
),
6795 " initializing argument %P of %qD", argnum
, fn
);
6798 /* Perform the conversions in CONVS on the expression EXPR. FN and
6799 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6800 indicates the `this' argument of a method. INNER is nonzero when
6801 being called to continue a conversion chain. It is negative when a
6802 reference binding will be applied, positive otherwise. If
6803 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6804 conversions will be emitted if appropriate. If C_CAST_P is true,
6805 this conversion is coming from a C-style cast; in that case,
6806 conversions to inaccessible bases are permitted. */
6809 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6810 bool issue_conversion_warnings
,
6811 bool c_cast_p
, tsubst_flags_t complain
)
6813 tree totype
= convs
->type
;
6814 diagnostic_t diag_kind
;
6816 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
6818 if (convs
->bad_p
&& !(complain
& tf_error
))
6819 return error_mark_node
;
6822 && convs
->kind
!= ck_user
6823 && convs
->kind
!= ck_list
6824 && convs
->kind
!= ck_ambig
6825 && (convs
->kind
!= ck_ref_bind
6826 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6827 && (convs
->kind
!= ck_rvalue
6828 || SCALAR_TYPE_P (totype
))
6829 && convs
->kind
!= ck_base
)
6831 bool complained
= false;
6832 conversion
*t
= convs
;
6834 /* Give a helpful error if this is bad because of excess braces. */
6835 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6836 && SCALAR_TYPE_P (totype
)
6837 && CONSTRUCTOR_NELTS (expr
) > 0
6838 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6840 complained
= permerror (loc
, "too many braces around initializer "
6842 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6843 && CONSTRUCTOR_NELTS (expr
) == 1)
6844 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6847 /* Give a helpful error if this is bad because a conversion to bool
6848 from std::nullptr_t requires direct-initialization. */
6849 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6850 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6851 complained
= permerror (loc
, "converting to %qH from %qI requires "
6852 "direct-initialization",
6853 totype
, TREE_TYPE (expr
));
6855 for (; t
; t
= next_conversion (t
))
6857 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6859 auto_diagnostic_group d
;
6860 complained
= permerror (loc
, "invalid user-defined conversion "
6861 "from %qH to %qI", TREE_TYPE (expr
),
6864 print_z_candidate (loc
, "candidate is:", t
->cand
);
6865 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6866 /*issue_conversion_warnings=*/false,
6869 if (convs
->kind
== ck_ref_bind
)
6870 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6871 LOOKUP_NORMAL
, NULL_TREE
,
6874 expr
= cp_convert (totype
, expr
, complain
);
6876 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
6879 else if (t
->kind
== ck_user
|| !t
->bad_p
)
6881 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6882 /*issue_conversion_warnings=*/false,
6887 else if (t
->kind
== ck_ambig
)
6888 return convert_like_real (t
, expr
, fn
, argnum
,
6889 /*issue_conversion_warnings=*/false,
6892 else if (t
->kind
== ck_identity
)
6897 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
6898 gcc_rich_location
richloc (loc
, &label
);
6899 complained
= permerror (&richloc
,
6900 "invalid conversion from %qH to %qI",
6901 TREE_TYPE (expr
), totype
);
6904 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
6906 return cp_convert (totype
, expr
, complain
);
6909 if (issue_conversion_warnings
&& (complain
& tf_warning
))
6910 conversion_null_warnings (totype
, expr
, fn
, argnum
);
6912 switch (convs
->kind
)
6916 struct z_candidate
*cand
= convs
->cand
;
6919 /* We chose the surrogate function from add_conv_candidate, now we
6920 actually need to build the conversion. */
6921 cand
= build_user_type_conversion_1 (totype
, expr
,
6922 LOOKUP_NO_CONVERSION
, complain
);
6924 tree convfn
= cand
->fn
;
6926 /* When converting from an init list we consider explicit
6927 constructors, but actually trying to call one is an error. */
6928 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
6929 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
6930 /* Unless this is for direct-list-initialization. */
6931 && !CONSTRUCTOR_IS_DIRECT_INIT (expr
)
6932 /* And in C++98 a default constructor can't be explicit. */
6933 && cxx_dialect
>= cxx11
)
6935 if (!(complain
& tf_error
))
6936 return error_mark_node
;
6937 location_t loc
= location_of (expr
);
6938 if (CONSTRUCTOR_NELTS (expr
) == 0
6939 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
6941 auto_diagnostic_group d
;
6942 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
6943 "would use explicit constructor %qD",
6945 inform (loc
, "in C++11 and above a default constructor "
6949 error ("converting to %qT from initializer list would use "
6950 "explicit constructor %qD", totype
, convfn
);
6953 /* If we're initializing from {}, it's value-initialization. */
6954 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6955 && CONSTRUCTOR_NELTS (expr
) == 0
6956 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
6958 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
6959 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
6960 return error_mark_node
;
6961 expr
= build_value_init (totype
, complain
);
6962 expr
= get_target_expr_sfinae (expr
, complain
);
6963 if (expr
!= error_mark_node
)
6965 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6966 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
6971 expr
= mark_rvalue_use (expr
);
6973 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
6975 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
6978 /* If this is a constructor or a function returning an aggr type,
6979 we need to build up a TARGET_EXPR. */
6980 if (DECL_CONSTRUCTOR_P (convfn
))
6982 expr
= build_cplus_new (totype
, expr
, complain
);
6984 /* Remember that this was list-initialization. */
6985 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
6986 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6992 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
6994 int nelts
= CONSTRUCTOR_NELTS (expr
);
6996 expr
= build_value_init (totype
, complain
);
6997 else if (nelts
== 1)
6998 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7002 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
7003 /*read_p=*/true, UNKNOWN_LOCATION
,
7004 /*reject_builtin=*/true);
7006 if (type_unknown_p (expr
))
7007 expr
= instantiate_type (totype
, expr
, complain
);
7008 if (expr
== null_node
7009 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
7010 /* If __null has been converted to an integer type, we do not want to
7011 continue to warn about uses of EXPR as an integer, rather than as a
7013 expr
= build_int_cst (totype
, 0);
7016 /* We leave bad_p off ck_ambig because overload resolution considers
7017 it valid, it just fails when we try to perform it. So we need to
7018 check complain here, too. */
7019 if (complain
& tf_error
)
7021 /* Call build_user_type_conversion again for the error. */
7022 int flags
= (convs
->need_temporary_p
7023 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7024 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7025 gcc_assert (seen_error ());
7026 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7028 return error_mark_node
;
7032 /* Conversion to std::initializer_list<T>. */
7033 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7034 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7035 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7036 tree array
, val
, field
;
7037 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7040 /* Convert all the elements. */
7041 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7043 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
, argnum
,
7044 false, false, complain
);
7045 if (sub
== error_mark_node
)
7047 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7048 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7049 return error_mark_node
;
7050 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
), NULL_TREE
, sub
);
7051 if (!TREE_CONSTANT (sub
))
7052 TREE_CONSTANT (new_ctor
) = false;
7054 /* Build up the array. */
7055 elttype
= cp_build_qualified_type
7056 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7057 array
= build_array_of_n_type (elttype
, len
);
7058 array
= finish_compound_literal (array
, new_ctor
, complain
);
7059 /* Take the address explicitly rather than via decay_conversion
7060 to avoid the error about taking the address of a temporary. */
7061 array
= cp_build_addr_expr (array
, complain
);
7062 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7063 if (array
== error_mark_node
)
7064 return error_mark_node
;
7066 /* Build up the initializer_list object. Note: fail gracefully
7067 if the object cannot be completed because, for example, no
7068 definition is provided (c++/80956). */
7069 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7071 return error_mark_node
;
7072 field
= next_initializable_field (TYPE_FIELDS (totype
));
7073 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7074 field
= next_initializable_field (DECL_CHAIN (field
));
7075 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7076 new_ctor
= build_constructor (totype
, vec
);
7077 return get_target_expr_sfinae (new_ctor
, complain
);
7081 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7083 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7084 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7085 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7087 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7089 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7092 expr
= reshape_init (totype
, expr
, complain
);
7093 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7095 if (expr
!= error_mark_node
)
7096 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7103 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7104 convs
->kind
== ck_ref_bind
7105 ? issue_conversion_warnings
: false,
7106 c_cast_p
, complain
);
7107 if (expr
== error_mark_node
)
7108 return error_mark_node
;
7110 switch (convs
->kind
)
7113 expr
= decay_conversion (expr
, complain
);
7114 if (expr
== error_mark_node
)
7116 if (complain
& tf_error
)
7118 auto_diagnostic_group d
;
7119 maybe_print_user_conv_context (convs
);
7120 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7122 return error_mark_node
;
7125 if (! MAYBE_CLASS_TYPE_P (totype
))
7128 /* Don't introduce copies when passing arguments along to the inherited
7130 if (current_function_decl
7131 && flag_new_inheriting_ctors
7132 && DECL_INHERITED_CTOR (current_function_decl
))
7135 if (TREE_CODE (expr
) == TARGET_EXPR
7136 && TARGET_EXPR_LIST_INIT_P (expr
))
7137 /* Copy-list-initialization doesn't actually involve a copy. */
7142 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7144 /* We are going to bind a reference directly to a base-class
7145 subobject of EXPR. */
7146 /* Build an expression for `*((base*) &expr)'. */
7147 expr
= convert_to_base (expr
, totype
,
7148 !c_cast_p
, /*nonnull=*/true, complain
);
7152 /* Copy-initialization where the cv-unqualified version of the source
7153 type is the same class as, or a derived class of, the class of the
7154 destination [is treated as direct-initialization]. [dcl.init] */
7155 flags
= LOOKUP_NORMAL
;
7156 if (convs
->user_conv_p
)
7157 /* This conversion is being done in the context of a user-defined
7158 conversion (i.e. the second step of copy-initialization), so
7159 don't allow any more. */
7160 flags
|= LOOKUP_NO_CONVERSION
;
7162 flags
|= LOOKUP_ONLYCONVERTING
;
7163 if (convs
->rvaluedness_matches_p
)
7164 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7165 flags
|= LOOKUP_PREFER_RVALUE
;
7166 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7167 if (diag_kind
&& complain
)
7169 auto_diagnostic_group d
;
7170 maybe_print_user_conv_context (convs
);
7171 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7174 return build_cplus_new (totype
, expr
, complain
);
7178 tree ref_type
= totype
;
7180 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7182 tree extype
= TREE_TYPE (expr
);
7183 auto_diagnostic_group d
;
7184 if (TYPE_REF_IS_RVALUE (ref_type
)
7186 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7187 "lvalue of type %qI", totype
, extype
);
7188 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7189 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7190 error_at (loc
, "cannot bind non-const lvalue reference of "
7191 "type %qH to an rvalue of type %qI", totype
, extype
);
7192 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7193 error_at (loc
, "binding reference of type %qH to %qI "
7194 "discards qualifiers", totype
, extype
);
7197 maybe_print_user_conv_context (convs
);
7198 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7200 return error_mark_node
;
7203 /* If necessary, create a temporary.
7205 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7206 that need temporaries, even when their types are reference
7207 compatible with the type of reference being bound, so the
7208 upcoming call to cp_build_addr_expr doesn't fail. */
7209 if (convs
->need_temporary_p
7210 || TREE_CODE (expr
) == CONSTRUCTOR
7211 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7213 /* Otherwise, a temporary of type "cv1 T1" is created and
7214 initialized from the initializer expression using the rules
7215 for a non-reference copy-initialization (8.5). */
7217 tree type
= TREE_TYPE (ref_type
);
7218 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7220 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7221 (type
, next_conversion (convs
)->type
));
7222 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7223 && !TYPE_REF_IS_RVALUE (ref_type
))
7225 /* If the reference is volatile or non-const, we
7226 cannot create a temporary. */
7227 if (lvalue
& clk_bitfield
)
7228 error_at (loc
, "cannot bind bitfield %qE to %qT",
7230 else if (lvalue
& clk_packed
)
7231 error_at (loc
, "cannot bind packed field %qE to %qT",
7234 error_at (loc
, "cannot bind rvalue %qE to %qT",
7236 return error_mark_node
;
7238 /* If the source is a packed field, and we must use a copy
7239 constructor, then building the target expr will require
7240 binding the field to the reference parameter to the
7241 copy constructor, and we'll end up with an infinite
7242 loop. If we can use a bitwise copy, then we'll be
7244 if ((lvalue
& clk_packed
)
7245 && CLASS_TYPE_P (type
)
7246 && type_has_nontrivial_copy_init (type
))
7248 error_at (loc
, "cannot bind packed field %qE to %qT",
7250 return error_mark_node
;
7252 if (lvalue
& clk_bitfield
)
7254 expr
= convert_bitfield_to_declared_type (expr
);
7255 expr
= fold_convert (type
, expr
);
7257 expr
= build_target_expr_with_type (expr
, type
, complain
);
7260 /* Take the address of the thing to which we will bind the
7262 expr
= cp_build_addr_expr (expr
, complain
);
7263 if (expr
== error_mark_node
)
7264 return error_mark_node
;
7266 /* Convert it to a pointer to the type referred to by the
7267 reference. This will adjust the pointer if a derived to
7268 base conversion is being performed. */
7269 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7271 /* Convert the pointer to the desired reference type. */
7272 return build_nop (ref_type
, expr
);
7276 return decay_conversion (expr
, complain
);
7279 /* ??? Should the address of a transaction-safe pointer point to the TM
7280 clone, and this conversion look up the primary function? */
7281 return build_nop (totype
, expr
);
7284 /* Warn about deprecated conversion if appropriate. */
7285 string_conv_p (totype
, expr
, 1);
7290 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7291 /*nonnull=*/false, complain
);
7292 return build_nop (totype
, expr
);
7295 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7296 c_cast_p
, complain
);
7302 if (convs
->check_narrowing
7303 && !check_narrowing (totype
, expr
, complain
,
7304 convs
->check_narrowing_const_only
))
7305 return error_mark_node
;
7307 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7308 if (issue_conversion_warnings
)
7309 expr
= cp_convert_and_check (totype
, expr
, complain
);
7311 expr
= cp_convert (totype
, expr
, complain
);
7316 /* ARG is being passed to a varargs function. Perform any conversions
7317 required. Return the converted value. */
7320 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7323 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
7327 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7328 standard conversions are performed. */
7329 arg
= decay_conversion (arg
, complain
);
7330 arg_type
= TREE_TYPE (arg
);
7333 If the argument has integral or enumeration type that is subject
7334 to the integral promotions (_conv.prom_), or a floating point
7335 type that is subject to the floating point promotion
7336 (_conv.fpprom_), the value of the argument is converted to the
7337 promoted type before the call. */
7338 if (TREE_CODE (arg_type
) == REAL_TYPE
7339 && (TYPE_PRECISION (arg_type
)
7340 < TYPE_PRECISION (double_type_node
))
7341 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7343 if ((complain
& tf_warning
)
7344 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7345 warning_at (loc
, OPT_Wdouble_promotion
,
7346 "implicit conversion from %qH to %qI when passing "
7347 "argument to function",
7348 arg_type
, double_type_node
);
7349 arg
= convert_to_real_nofold (double_type_node
, arg
);
7351 else if (NULLPTR_TYPE_P (arg_type
))
7352 arg
= null_pointer_node
;
7353 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7355 if (SCOPED_ENUM_P (arg_type
))
7357 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7359 prom
= cp_perform_integral_promotions (prom
, complain
);
7360 if (abi_version_crosses (6)
7361 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7362 && (complain
& tf_warning
))
7363 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
7364 "%qT before -fabi-version=6, %qT after", arg_type
,
7365 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7366 if (!abi_version_at_least (6))
7370 arg
= cp_perform_integral_promotions (arg
, complain
);
7373 arg
= require_complete_type_sfinae (arg
, complain
);
7374 arg_type
= TREE_TYPE (arg
);
7376 if (arg
!= error_mark_node
7377 /* In a template (or ill-formed code), we can have an incomplete type
7378 even after require_complete_type_sfinae, in which case we don't know
7379 whether it has trivial copy or not. */
7380 && COMPLETE_TYPE_P (arg_type
)
7381 && !cp_unevaluated_operand
)
7383 /* [expr.call] 5.2.2/7:
7384 Passing a potentially-evaluated argument of class type (Clause 9)
7385 with a non-trivial copy constructor or a non-trivial destructor
7386 with no corresponding parameter is conditionally-supported, with
7387 implementation-defined semantics.
7389 We support it as pass-by-invisible-reference, just like a normal
7392 If the call appears in the context of a sizeof expression,
7393 it is not potentially-evaluated. */
7394 if (type_has_nontrivial_copy_init (arg_type
)
7395 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7397 arg
= force_rvalue (arg
, complain
);
7398 if (complain
& tf_warning
)
7399 warning (OPT_Wconditionally_supported
,
7400 "passing objects of non-trivially-copyable "
7401 "type %q#T through %<...%> is conditionally supported",
7403 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7405 /* Build up a real lvalue-to-rvalue conversion in case the
7406 copy constructor is trivial but not callable. */
7407 else if (CLASS_TYPE_P (arg_type
))
7408 force_rvalue (arg
, complain
);
7415 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7418 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7420 if (processing_template_decl
)
7422 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7423 SET_EXPR_LOCATION (r
, loc
);
7427 type
= complete_type_or_else (type
, NULL_TREE
);
7429 if (expr
== error_mark_node
|| !type
)
7430 return error_mark_node
;
7432 expr
= mark_lvalue_use (expr
);
7434 if (TYPE_REF_P (type
))
7436 error ("cannot receive reference type %qT through %<...%>", type
);
7437 return error_mark_node
;
7440 if (type_has_nontrivial_copy_init (type
)
7441 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7443 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7444 it as pass by invisible reference. */
7445 warning_at (loc
, OPT_Wconditionally_supported
,
7446 "receiving objects of non-trivially-copyable type %q#T "
7447 "through %<...%> is conditionally-supported", type
);
7449 tree ref
= cp_build_reference_type (type
, false);
7450 expr
= build_va_arg (loc
, expr
, ref
);
7451 return convert_from_reference (expr
);
7454 tree ret
= build_va_arg (loc
, expr
, type
);
7455 if (CLASS_TYPE_P (type
))
7456 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7457 know how to handle it. */
7458 ret
= get_target_expr (ret
);
7462 /* TYPE has been given to va_arg. Apply the default conversions which
7463 would have happened when passed via ellipsis. Return the promoted
7464 type, or the passed type if there is no change. */
7467 cxx_type_promotes_to (tree type
)
7471 /* Perform the array-to-pointer and function-to-pointer
7473 type
= type_decays_to (type
);
7475 promote
= type_promotes_to (type
);
7476 if (same_type_p (type
, promote
))
7482 /* ARG is a default argument expression being passed to a parameter of
7483 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7484 zero-based argument number. Do any required conversions. Return
7485 the converted value. */
7487 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7489 push_defarg_context (tree fn
)
7490 { vec_safe_push (default_arg_context
, fn
); }
7493 pop_defarg_context (void)
7494 { default_arg_context
->pop (); }
7497 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7498 tsubst_flags_t complain
)
7503 /* See through clones. */
7504 fn
= DECL_ORIGIN (fn
);
7505 /* And inheriting ctors. */
7506 if (flag_new_inheriting_ctors
)
7507 fn
= strip_inheriting_ctors (fn
);
7509 /* Detect recursion. */
7510 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7513 if (complain
& tf_error
)
7514 error ("recursive evaluation of default argument for %q#D", fn
);
7515 return error_mark_node
;
7518 /* If the ARG is an unparsed default argument expression, the
7519 conversion cannot be performed. */
7520 if (TREE_CODE (arg
) == DEFAULT_ARG
)
7522 if (complain
& tf_error
)
7523 error ("call to %qD uses the default argument for parameter %P, which "
7524 "is not yet defined", fn
, parmnum
);
7525 return error_mark_node
;
7528 push_defarg_context (fn
);
7530 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7531 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7537 The names in the expression are bound, and the semantic
7538 constraints are checked, at the point where the default
7539 expressions appears.
7541 we must not perform access checks here. */
7542 push_deferring_access_checks (dk_no_check
);
7543 /* We must make a copy of ARG, in case subsequent processing
7544 alters any part of it. */
7545 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7547 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7548 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7550 arg
= convert_for_arg_passing (type
, arg
, complain
);
7551 pop_deferring_access_checks();
7553 pop_defarg_context ();
7558 /* Returns the type which will really be used for passing an argument of
7562 type_passed_as (tree type
)
7564 /* Pass classes with copy ctors by invisible reference. */
7565 if (TREE_ADDRESSABLE (type
))
7567 type
= build_reference_type (type
);
7568 /* There are no other pointers to this temporary. */
7569 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7571 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7572 && INTEGRAL_TYPE_P (type
)
7573 && COMPLETE_TYPE_P (type
)
7574 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7575 type
= integer_type_node
;
7580 /* Actually perform the appropriate conversion. */
7583 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7587 /* If VAL is a bitfield, then -- since it has already been converted
7588 to TYPE -- it cannot have a precision greater than TYPE.
7590 If it has a smaller precision, we must widen it here. For
7591 example, passing "int f:3;" to a function expecting an "int" will
7592 not result in any conversion before this point.
7594 If the precision is the same we must not risk widening. For
7595 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7596 often have type "int", even though the C++ type for the field is
7597 "long long". If the value is being passed to a function
7598 expecting an "int", then no conversions will be required. But,
7599 if we call convert_bitfield_to_declared_type, the bitfield will
7600 be converted to "long long". */
7601 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7603 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7604 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7606 if (val
== error_mark_node
)
7608 /* Pass classes with copy ctors by invisible reference. */
7609 else if (TREE_ADDRESSABLE (type
))
7610 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7611 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7612 && INTEGRAL_TYPE_P (type
)
7613 && COMPLETE_TYPE_P (type
)
7614 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7615 val
= cp_perform_integral_promotions (val
, complain
);
7616 if (complain
& tf_warning
)
7618 if (warn_suggest_attribute_format
)
7620 tree rhstype
= TREE_TYPE (val
);
7621 const enum tree_code coder
= TREE_CODE (rhstype
);
7622 const enum tree_code codel
= TREE_CODE (type
);
7623 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7625 && check_missing_format_attribute (type
, rhstype
))
7626 warning (OPT_Wsuggest_attribute_format
,
7627 "argument of function call might be a candidate "
7628 "for a format attribute");
7630 maybe_warn_parm_abi (type
, cp_expr_loc_or_loc (val
, input_location
));
7633 warn_for_address_or_pointer_of_packed_member (false, type
, val
);
7638 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7639 which just decay_conversion or no conversions at all should be done.
7640 This is true for some builtins which don't act like normal functions.
7641 Return 2 if no conversions at all should be done, 1 if just
7642 decay_conversion. Return 3 for special treatment of the 3rd argument
7643 for __builtin_*_overflow_p. */
7646 magic_varargs_p (tree fn
)
7648 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7649 switch (DECL_FUNCTION_CODE (fn
))
7651 case BUILT_IN_CLASSIFY_TYPE
:
7652 case BUILT_IN_CONSTANT_P
:
7653 case BUILT_IN_NEXT_ARG
:
7654 case BUILT_IN_VA_START
:
7657 case BUILT_IN_ADD_OVERFLOW_P
:
7658 case BUILT_IN_SUB_OVERFLOW_P
:
7659 case BUILT_IN_MUL_OVERFLOW_P
:
7663 return lookup_attribute ("type generic",
7664 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7670 /* Returns the decl of the dispatcher function if FN is a function version. */
7673 get_function_version_dispatcher (tree fn
)
7675 tree dispatcher_decl
= NULL
;
7677 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7678 && DECL_FUNCTION_VERSIONED (fn
));
7680 gcc_assert (targetm
.get_function_versions_dispatcher
);
7681 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7683 if (dispatcher_decl
== NULL
)
7685 error_at (input_location
, "use of multiversioned function "
7686 "without a default");
7690 retrofit_lang_decl (dispatcher_decl
);
7691 gcc_assert (dispatcher_decl
!= NULL
);
7692 return dispatcher_decl
;
7695 /* fn is a function version dispatcher that is marked used. Mark all the
7696 semantically identical function versions it will dispatch as used. */
7699 mark_versions_used (tree fn
)
7701 struct cgraph_node
*node
;
7702 struct cgraph_function_version_info
*node_v
;
7703 struct cgraph_function_version_info
*it_v
;
7705 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7707 node
= cgraph_node::get (fn
);
7711 gcc_assert (node
->dispatcher_function
);
7713 node_v
= node
->function_version ();
7717 /* All semantically identical versions are chained. Traverse and mark each
7718 one of them as used. */
7719 it_v
= node_v
->next
;
7720 while (it_v
!= NULL
)
7722 mark_used (it_v
->this_node
->decl
);
7727 /* Build a call to "the copy constructor" for the type of A, even if it
7728 wouldn't be selected by normal overload resolution. Used for
7732 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7734 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7735 tree binfo
= TYPE_BINFO (ctype
);
7736 tree copy
= get_copy_ctor (ctype
, complain
);
7737 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7738 tree ob
= build_dummy_object (ctype
);
7739 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7740 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7741 LOOKUP_NORMAL
, NULL
, complain
);
7742 release_tree_vector (args
);
7746 /* Return true iff T refers to a base field. */
7749 is_base_field_ref (tree t
)
7752 if (TREE_CODE (t
) == ADDR_EXPR
)
7753 t
= TREE_OPERAND (t
, 0);
7754 if (TREE_CODE (t
) == COMPONENT_REF
)
7755 t
= TREE_OPERAND (t
, 1);
7756 if (TREE_CODE (t
) == FIELD_DECL
)
7757 return DECL_FIELD_IS_BASE (t
);
7761 /* We can't elide a copy from a function returning by value to a base
7762 subobject, as the callee might clobber tail padding. Return true iff this
7763 could be that case. */
7766 unsafe_copy_elision_p (tree target
, tree exp
)
7768 /* Copy elision only happens with a TARGET_EXPR. */
7769 if (TREE_CODE (exp
) != TARGET_EXPR
)
7771 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7772 /* It's safe to elide the copy for a class with no tail padding. */
7773 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7775 /* It's safe to elide the copy if we aren't initializing a base object. */
7776 if (!is_base_field_ref (target
))
7778 tree init
= TARGET_EXPR_INITIAL (exp
);
7779 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7780 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7781 init
= TREE_OPERAND (init
, 1);
7782 if (TREE_CODE (init
) == COND_EXPR
)
7784 /* We'll end up copying from each of the arms of the COND_EXPR directly
7785 into the target, so look at them. */
7786 if (tree op
= TREE_OPERAND (init
, 1))
7787 if (unsafe_copy_elision_p (target
, op
))
7789 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7791 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7792 && !AGGR_INIT_VIA_CTOR_P (init
));
7795 /* True iff C is a conversion that binds a reference to a prvalue. */
7798 conv_binds_ref_to_prvalue (conversion
*c
)
7800 if (c
->kind
!= ck_ref_bind
)
7802 if (c
->need_temporary_p
)
7805 c
= next_conversion (c
);
7807 if (c
->kind
== ck_rvalue
)
7809 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7811 if (c
->kind
== ck_identity
&& c
->u
.expr
7812 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7818 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7819 class type or a pointer to class type. */
7822 build_trivial_dtor_call (tree instance
)
7824 gcc_assert (!is_dummy_object (instance
));
7826 if (!flag_lifetime_dse
)
7829 return fold_convert (void_type_node
, instance
);
7832 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
7834 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7836 instance
= cp_build_fold_indirect_ref (instance
);
7839 /* A trivial destructor should still clobber the object. */
7840 tree clobber
= build_clobber (TREE_TYPE (instance
));
7841 return build2 (MODIFY_EXPR
, void_type_node
,
7845 /* Subroutine of the various build_*_call functions. Overload resolution
7846 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7847 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7848 bitmask of various LOOKUP_* flags which apply to the call itself. */
7851 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7854 const vec
<tree
, va_gc
> *args
= cand
->args
;
7855 tree first_arg
= cand
->first_arg
;
7856 conversion
**convs
= cand
->convs
;
7858 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
7863 unsigned int arg_index
= 0;
7867 bool already_used
= false;
7869 /* In a template, there is no need to perform all of the work that
7870 is normally done. We are only interested in the type of the call
7871 expression, i.e., the return type of the function. Any semantic
7872 errors will be deferred until the template is instantiated. */
7873 if (processing_template_decl
)
7877 const tree
*argarray
;
7880 if (undeduced_auto_decl (fn
))
7881 mark_used (fn
, complain
);
7883 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
7887 return_type
= TREE_TYPE (TREE_TYPE (fn
));
7888 nargs
= vec_safe_length (args
);
7889 if (first_arg
== NULL_TREE
)
7890 argarray
= args
->address ();
7898 alcarray
= XALLOCAVEC (tree
, nargs
);
7899 alcarray
[0] = build_this (first_arg
);
7900 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
7901 alcarray
[ix
+ 1] = arg
;
7902 argarray
= alcarray
;
7905 addr
= build_addr_func (fn
, complain
);
7906 if (addr
== error_mark_node
)
7907 return error_mark_node
;
7908 expr
= build_call_array_loc (input_location
, return_type
,
7909 addr
, nargs
, argarray
);
7910 if (TREE_THIS_VOLATILE (fn
) && cfun
)
7911 current_function_returns_abnormally
= 1;
7912 return convert_from_reference (expr
);
7915 /* Give any warnings we noticed during overload resolution. */
7916 if (cand
->warnings
&& (complain
& tf_warning
))
7918 struct candidate_warning
*w
;
7919 for (w
= cand
->warnings
; w
; w
= w
->next
)
7920 joust (cand
, w
->loser
, 1, complain
);
7923 /* Core issue 2327: P0135 doesn't say how to handle the case where the
7924 argument to the copy constructor ends up being a prvalue after
7925 conversion. Let's do the normal processing, but pretend we aren't
7926 actually using the copy constructor. */
7927 bool force_elide
= false;
7928 if (cxx_dialect
>= cxx17
7929 && cand
->num_convs
== 1
7930 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
7931 && (DECL_COPY_CONSTRUCTOR_P (fn
)
7932 || DECL_MOVE_CONSTRUCTOR_P (fn
))
7933 && conv_binds_ref_to_prvalue (convs
[0]))
7936 goto not_really_used
;
7939 /* OK, we're actually calling this inherited constructor; set its deletedness
7940 appropriately. We can get away with doing this here because calling is
7941 the only way to refer to a constructor. */
7942 if (DECL_INHERITED_CTOR (fn
))
7943 deduce_inheriting_ctor (fn
);
7945 /* Make =delete work with SFINAE. */
7946 if (DECL_DELETED_FN (fn
))
7948 if (complain
& tf_error
)
7950 return error_mark_node
;
7953 if (DECL_FUNCTION_MEMBER_P (fn
))
7956 /* If FN is a template function, two cases must be considered.
7961 template <class T> void f();
7963 template <class T> struct B {
7967 struct C : A, B<int> {
7969 using B<int>::g; // #2
7972 In case #1 where `A::f' is a member template, DECL_ACCESS is
7973 recorded in the primary template but not in its specialization.
7974 We check access of FN using its primary template.
7976 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7977 because it is a member of class template B, DECL_ACCESS is
7978 recorded in the specialization `B<int>::g'. We cannot use its
7979 primary template because `B<T>::g' and `B<int>::g' may have
7980 different access. */
7981 if (DECL_TEMPLATE_INFO (fn
)
7982 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
7983 access_fn
= DECL_TI_TEMPLATE (fn
);
7986 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
7988 return error_mark_node
;
7991 /* If we're checking for implicit delete, don't bother with argument
7993 if (flags
& LOOKUP_SPECULATIVE
)
7995 if (cand
->viable
== 1)
7997 else if (!(complain
& tf_error
))
7998 /* Reject bad conversions now. */
7999 return error_mark_node
;
8000 /* else continue to get conversion error. */
8005 /* N3276 magic doesn't apply to nested calls. */
8006 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
8007 complain
&= ~tf_decltype
;
8008 /* No-Cleanup doesn't apply to nested calls either. */
8009 tsubst_flags_t no_cleanup_complain
= complain
;
8010 complain
&= ~tf_no_cleanup
;
8012 /* Find maximum size of vector to hold converted arguments. */
8013 parmlen
= list_length (parm
);
8014 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8015 if (parmlen
> nargs
)
8017 argarray
= XALLOCAVEC (tree
, nargs
);
8019 /* The implicit parameters to a constructor are not considered by overload
8020 resolution, and must be of the proper type. */
8021 if (DECL_CONSTRUCTOR_P (fn
))
8024 if (first_arg
!= NULL_TREE
)
8026 object_arg
= first_arg
;
8027 first_arg
= NULL_TREE
;
8031 object_arg
= (*args
)[arg_index
];
8034 argarray
[j
++] = build_this (object_arg
);
8035 parm
= TREE_CHAIN (parm
);
8036 /* We should never try to call the abstract constructor. */
8037 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8039 if (DECL_HAS_VTT_PARM_P (fn
))
8041 argarray
[j
++] = (*args
)[arg_index
];
8043 parm
= TREE_CHAIN (parm
);
8046 if (flags
& LOOKUP_PREFER_RVALUE
)
8048 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8049 the first parameter of the selected constructor is not an rvalue
8050 reference to the object's type (possibly cv-qualified)...." */
8051 gcc_assert (!(complain
& tf_error
));
8052 tree ptype
= convs
[0]->type
;
8053 if (!TYPE_REF_P (ptype
)
8054 || !TYPE_REF_IS_RVALUE (ptype
)
8055 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8056 return error_mark_node
;
8059 /* Bypass access control for 'this' parameter. */
8060 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8062 tree parmtype
= TREE_VALUE (parm
);
8063 tree arg
= build_this (first_arg
!= NULL_TREE
8065 : (*args
)[arg_index
]);
8066 tree argtype
= TREE_TYPE (arg
);
8070 if (arg
== error_mark_node
)
8071 return error_mark_node
;
8073 if (convs
[i
]->bad_p
)
8075 if (complain
& tf_error
)
8077 auto_diagnostic_group d
;
8078 if (permerror (input_location
, "passing %qT as %<this%> "
8079 "argument discards qualifiers",
8080 TREE_TYPE (argtype
)))
8081 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8084 return error_mark_node
;
8087 /* See if the function member or the whole class type is declared
8088 final and the call can be devirtualized. */
8089 if (DECL_FINAL_P (fn
)
8090 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
8091 flags
|= LOOKUP_NONVIRTUAL
;
8093 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8094 X is called for an object that is not of type X, or of a type
8095 derived from X, the behavior is undefined.
8097 So we can assume that anything passed as 'this' is non-null, and
8098 optimize accordingly. */
8099 gcc_assert (TYPE_PTR_P (parmtype
));
8100 /* Convert to the base in which the function was declared. */
8101 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8102 converted_arg
= build_base_path (PLUS_EXPR
,
8104 cand
->conversion_path
,
8106 /* Check that the base class is accessible. */
8107 if (!accessible_base_p (TREE_TYPE (argtype
),
8108 BINFO_TYPE (cand
->conversion_path
), true))
8110 if (complain
& tf_error
)
8111 error ("%qT is not an accessible base of %qT",
8112 BINFO_TYPE (cand
->conversion_path
),
8113 TREE_TYPE (argtype
));
8115 return error_mark_node
;
8117 /* If fn was found by a using declaration, the conversion path
8118 will be to the derived class, not the base declaring fn. We
8119 must convert from derived to base. */
8120 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8121 TREE_TYPE (parmtype
), ba_unique
,
8123 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8124 base_binfo
, 1, complain
);
8126 argarray
[j
++] = converted_arg
;
8127 parm
= TREE_CHAIN (parm
);
8128 if (first_arg
!= NULL_TREE
)
8129 first_arg
= NULL_TREE
;
8136 gcc_assert (first_arg
== NULL_TREE
);
8137 for (; arg_index
< vec_safe_length (args
) && parm
;
8138 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8140 tree type
= TREE_VALUE (parm
);
8141 tree arg
= (*args
)[arg_index
];
8142 bool conversion_warning
= true;
8146 /* If the argument is NULL and used to (implicitly) instantiate a
8147 template function (and bind one of the template arguments to
8148 the type of 'long int'), we don't want to warn about passing NULL
8149 to non-pointer argument.
8150 For example, if we have this template function:
8152 template<typename T> void func(T x) {}
8154 we want to warn (when -Wconversion is enabled) in this case:
8160 but not in this case:
8166 if (null_node_p (arg
)
8167 && DECL_TEMPLATE_INFO (fn
)
8168 && cand
->template_decl
8169 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8170 conversion_warning
= false;
8172 /* Warn about initializer_list deduction that isn't currently in the
8174 if (cxx_dialect
> cxx98
8175 && flag_deduce_init_list
8176 && cand
->template_decl
8177 && is_std_init_list (non_reference (type
))
8178 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
8180 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
8181 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
8182 tree patparm
= get_pattern_parm (realparm
, tmpl
);
8183 tree pattype
= TREE_TYPE (patparm
);
8184 if (PACK_EXPANSION_P (pattype
))
8185 pattype
= PACK_EXPANSION_PATTERN (pattype
);
8186 pattype
= non_reference (pattype
);
8188 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
8189 && (cand
->explicit_targs
== NULL_TREE
8190 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
8191 <= TEMPLATE_TYPE_IDX (pattype
))))
8193 pedwarn (input_location
, 0, "deducing %qT as %qT",
8194 non_reference (TREE_TYPE (patparm
)),
8195 non_reference (type
));
8196 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
8197 " in call to %qD", cand
->fn
);
8198 pedwarn (input_location
, 0,
8199 " (you can disable this with -fno-deduce-init-list)");
8203 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8204 knows not to allow any more UDCs. This needs to happen after we
8205 process cand->warnings. */
8206 if (flags
& LOOKUP_NO_CONVERSION
)
8207 conv
->user_conv_p
= true;
8209 tsubst_flags_t arg_complain
= complain
;
8210 if (!conversion_warning
)
8211 arg_complain
&= ~tf_warning
;
8213 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8215 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8217 if (val
== error_mark_node
)
8218 return error_mark_node
;
8220 argarray
[j
++] = val
;
8223 /* Default arguments */
8224 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8226 if (TREE_VALUE (parm
) == error_mark_node
)
8227 return error_mark_node
;
8228 val
= convert_default_arg (TREE_VALUE (parm
),
8229 TREE_PURPOSE (parm
),
8232 if (val
== error_mark_node
)
8233 return error_mark_node
;
8234 argarray
[j
++] = val
;
8238 int magic
= magic_varargs_p (fn
);
8239 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8241 tree a
= (*args
)[arg_index
];
8242 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8244 /* Do no conversions for certain magic varargs. */
8245 a
= mark_type_use (a
);
8246 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8247 return error_mark_node
;
8249 else if (magic
!= 0)
8250 /* For other magic varargs only do decay_conversion. */
8251 a
= decay_conversion (a
, complain
);
8252 else if (DECL_CONSTRUCTOR_P (fn
)
8253 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8256 /* Avoid infinite recursion trying to call A(...). */
8257 if (complain
& tf_error
)
8258 /* Try to call the actual copy constructor for a good error. */
8259 call_copy_ctor (a
, complain
);
8260 return error_mark_node
;
8263 a
= convert_arg_to_ellipsis (a
, complain
);
8264 if (a
== error_mark_node
)
8265 return error_mark_node
;
8269 gcc_assert (j
<= nargs
);
8272 /* Avoid to do argument-transformation, if warnings for format, and for
8273 nonnull are disabled. Just in case that at least one of them is active
8274 the check_function_arguments function might warn about something. */
8276 bool warned_p
= false;
8279 || warn_suggest_attribute_format
8282 tree
*fargs
= (!nargs
? argarray
8283 : (tree
*) alloca (nargs
* sizeof (tree
)));
8284 for (j
= 0; j
< nargs
; j
++)
8286 /* For -Wformat undo the implicit passing by hidden reference
8287 done by convert_arg_to_ellipsis. */
8288 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8289 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8290 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8292 fargs
[j
] = argarray
[j
];
8295 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8296 nargs
, fargs
, NULL
);
8299 if (DECL_INHERITED_CTOR (fn
))
8301 /* Check for passing ellipsis arguments to an inherited constructor. We
8302 could handle this by open-coding the inherited constructor rather than
8303 defining it, but let's not bother now. */
8304 if (!cp_unevaluated_operand
8306 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8308 if (complain
& tf_error
)
8310 sorry ("passing arguments to ellipsis of inherited constructor "
8312 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8314 return error_mark_node
;
8317 /* A base constructor inheriting from a virtual base doesn't get the
8318 inherited arguments, just this and __vtt. */
8319 if (ctor_omit_inherited_parms (fn
))
8323 /* Avoid actually calling copy constructors and copy assignment operators,
8326 if (! flag_elide_constructors
&& !force_elide
)
8327 /* Do things the hard way. */;
8328 else if (cand
->num_convs
== 1
8329 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8330 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8331 /* It's unsafe to elide the constructor when handling
8332 a noexcept-expression, it may evaluate to the wrong
8333 value (c++/53025). */
8334 && (force_elide
|| cp_noexcept_operand
== 0))
8337 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8339 bool trivial
= trivial_fn_p (fn
);
8341 /* Pull out the real argument, disregarding const-correctness. */
8343 /* Strip the reference binding for the constructor parameter. */
8344 if (CONVERT_EXPR_P (targ
)
8345 && TYPE_REF_P (TREE_TYPE (targ
)))
8346 targ
= TREE_OPERAND (targ
, 0);
8347 /* But don't strip any other reference bindings; binding a temporary to a
8348 reference prevents copy elision. */
8349 while ((CONVERT_EXPR_P (targ
)
8350 && !TYPE_REF_P (TREE_TYPE (targ
)))
8351 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8352 targ
= TREE_OPERAND (targ
, 0);
8353 if (TREE_CODE (targ
) == ADDR_EXPR
)
8355 targ
= TREE_OPERAND (targ
, 0);
8356 if (!same_type_ignoring_top_level_qualifiers_p
8357 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8366 arg
= cp_build_fold_indirect_ref (arg
);
8368 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8370 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8371 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8373 /* It's from binding the ref parm to a packed field. */
8374 || convs
[0]->need_temporary_p
8376 /* See unsafe_copy_elision_p. */
8377 || DECL_BASE_CONSTRUCTOR_P (fn
));
8380 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8381 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8383 /* [class.copy]: the copy constructor is implicitly defined even if the
8384 implementation elided its use. But don't warn about deprecation when
8385 eliding a temporary, as then no copy is actually performed. */
8386 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8388 /* The language says this isn't called. */;
8391 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8392 return error_mark_node
;
8393 already_used
= true;
8396 cp_warn_deprecated_use (fn
, complain
);
8398 /* If we're creating a temp and we already have one, don't create a
8399 new one. If we're not creating a temp but we get one, use
8400 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8401 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8402 temp or an INIT_EXPR otherwise. */
8403 if (is_dummy_object (fa
))
8405 if (TREE_CODE (arg
) == TARGET_EXPR
)
8408 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8410 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8413 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8415 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8419 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8420 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8421 && trivial_fn_p (fn
))
8423 tree to
= cp_stabilize_reference
8424 (cp_build_fold_indirect_ref (argarray
[0]));
8425 tree type
= TREE_TYPE (to
);
8426 tree as_base
= CLASSTYPE_AS_BASE (type
);
8427 tree arg
= argarray
[1];
8428 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
8430 if (is_really_empty_class (type
))
8432 /* Avoid copying empty classes. */
8433 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8434 TREE_NO_WARNING (val
) = 1;
8436 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8438 if (is_std_init_list (type
)
8439 && conv_binds_ref_to_prvalue (convs
[1]))
8440 warning_at (loc
, OPT_Winit_list_lifetime
,
8441 "assignment from temporary initializer_list does not "
8442 "extend the lifetime of the underlying array");
8443 arg
= cp_build_fold_indirect_ref (arg
);
8444 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8448 /* We must only copy the non-tail padding parts. */
8450 tree array_type
, alias_set
;
8452 arg2
= TYPE_SIZE_UNIT (as_base
);
8453 arg0
= cp_build_addr_expr (to
, complain
);
8455 array_type
= build_array_type (unsigned_char_type_node
,
8457 (size_binop (MINUS_EXPR
,
8458 arg2
, size_int (1))));
8459 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8460 t
= build2 (MODIFY_EXPR
, void_type_node
,
8461 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8462 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8463 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8464 TREE_NO_WARNING (val
) = 1;
8467 cp_warn_deprecated_use (fn
, complain
);
8471 else if (trivial_fn_p (fn
))
8473 if (DECL_DESTRUCTOR_P (fn
))
8474 return build_trivial_dtor_call (argarray
[0]);
8475 else if (default_ctor_p (fn
))
8477 if (is_dummy_object (argarray
[0]))
8478 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8479 no_cleanup_complain
);
8481 return cp_build_fold_indirect_ref (argarray
[0]);
8485 gcc_assert (!force_elide
);
8488 && !mark_used (fn
, complain
))
8489 return error_mark_node
;
8491 /* Warn if the built-in writes to an object of a non-trivial type. */
8492 if (warn_class_memaccess
8493 && vec_safe_length (args
) >= 2
8494 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8495 maybe_warn_class_memaccess (input_location
, fn
, args
);
8497 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8500 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8502 ba_any
, NULL
, complain
);
8503 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8505 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8507 if (TREE_SIDE_EFFECTS (argarray
[0]))
8508 argarray
[0] = save_expr (argarray
[0]);
8509 t
= build_pointer_type (TREE_TYPE (fn
));
8510 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8515 fn
= build_addr_func (fn
, complain
);
8516 if (fn
== error_mark_node
)
8517 return error_mark_node
;
8520 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8521 if (call
== error_mark_node
)
8523 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8525 tree c
= extract_call_expr (call
);
8526 /* build_new_op_1 will clear this when appropriate. */
8527 CALL_EXPR_ORDERED_ARGS (c
) = true;
8531 tree c
= extract_call_expr (call
);
8532 if (TREE_CODE (c
) == CALL_EXPR
)
8533 TREE_NO_WARNING (c
) = 1;
8541 /* Return the DECL of the first non-static subobject of class TYPE
8542 that satisfies the predicate PRED or null if none can be found. */
8544 template <class Predicate
>
8546 first_non_static_field (tree type
, Predicate pred
)
8548 if (!type
|| !CLASS_TYPE_P (type
))
8551 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8553 if (TREE_CODE (field
) != FIELD_DECL
)
8555 if (TREE_STATIC (field
))
8563 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8564 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8566 tree base
= TREE_TYPE (base_binfo
);
8569 if (tree field
= first_non_static_field (base
, pred
))
8576 struct NonPublicField
8578 bool operator() (const_tree t
)
8580 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8584 /* Return the DECL of the first non-public subobject of class TYPE
8585 or null if none can be found. */
8588 first_non_public_field (tree type
)
8590 return first_non_static_field (type
, NonPublicField ());
8593 struct NonTrivialField
8595 bool operator() (const_tree t
)
8597 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8601 /* Return the DECL of the first non-trivial subobject of class TYPE
8602 or null if none can be found. */
8605 first_non_trivial_field (tree type
)
8607 return first_non_static_field (type
, NonTrivialField ());
8610 } /* unnamed namespace */
8612 /* Return true if all copy and move assignment operator overloads for
8613 class TYPE are trivial and at least one of them is not deleted and,
8614 when ACCESS is set, accessible. Return false otherwise. Set
8615 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8616 copy or move assignment. */
8619 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8621 tree fns
= get_class_binding (type
, assign_op_identifier
);
8622 bool all_trivial
= true;
8624 /* Iterate over overloads of the assignment operator, checking
8625 accessible copy assignments for triviality. */
8627 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8631 /* Skip operators that aren't copy assignments. */
8635 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8636 || accessible_p (TYPE_BINFO (type
), f
, true));
8638 /* Skip template assignment operators and deleted functions. */
8639 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8645 if (!accessible
|| !trivial_fn_p (f
))
8646 all_trivial
= false;
8648 /* Break early when both properties have been determined. */
8649 if (*hasassign
&& !all_trivial
)
8653 /* Return true if they're all trivial and one of the expressions
8654 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8655 tree ref
= cp_build_reference_type (type
, false);
8657 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8658 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8661 /* Return true if all copy and move ctor overloads for class TYPE are
8662 trivial and at least one of them is not deleted and, when ACCESS is
8663 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8664 to true when the TYPE has a (not necessarily trivial) default and copy
8665 (or move) ctor, respectively. */
8668 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8670 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8671 bool all_trivial
= true;
8673 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8677 /* Skip template constructors. */
8678 if (TREE_CODE (f
) != FUNCTION_DECL
)
8681 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8683 /* Skip ctors other than default, copy, and move. */
8684 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8687 if (DECL_DELETED_FN (f
))
8690 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8691 || accessible_p (TYPE_BINFO (type
), f
, true));
8694 hasctor
[cpy_or_move_ctor_p
] = true;
8696 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8697 all_trivial
= false;
8699 /* Break early when both properties have been determined. */
8700 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8707 /* Issue a warning on a call to the built-in function FNDECL if it is
8708 a raw memory write whose destination is not an object of (something
8709 like) trivial or standard layout type with a non-deleted assignment
8710 and copy ctor. Detects const correctness violations, corrupting
8711 references, virtual table pointers, and bypassing non-trivial
8715 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8716 const vec
<tree
, va_gc
> *args
)
8718 /* Except for bcopy where it's second, the destination pointer is
8719 the first argument for all functions handled here. Compute
8720 the index of the destination and source arguments. */
8721 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8722 unsigned srcidx
= !dstidx
;
8724 tree dest
= (*args
)[dstidx
];
8725 if (!TREE_TYPE (dest
) || !INDIRECT_TYPE_P (TREE_TYPE (dest
)))
8728 tree srctype
= NULL_TREE
;
8730 /* Determine the type of the pointed-to object and whether it's
8731 a complete class type. */
8732 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8734 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8737 /* Check to see if the raw memory call is made by a non-static member
8738 function with THIS as the destination argument for the destination
8739 type. If so, and if the class has no non-trivial bases or members,
8740 be more permissive. */
8741 if (current_function_decl
8742 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8743 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8745 tree ctx
= DECL_CONTEXT (current_function_decl
);
8746 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8747 tree binfo
= TYPE_BINFO (ctx
);
8750 && !BINFO_VTABLE (binfo
)
8751 && !first_non_trivial_field (desttype
))
8755 /* True if the class is trivial. */
8756 bool trivial
= trivial_type_p (desttype
);
8758 /* Set to true if DESTYPE has an accessible copy assignment. */
8759 bool hasassign
= false;
8760 /* True if all of the class' overloaded copy assignment operators
8761 are all trivial (and not deleted) and at least one of them is
8763 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8765 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8767 bool hasctors
[2] = { false, false };
8769 /* True if all of the class' overloaded copy constructors are all
8770 trivial (and not deleted) and at least one of them is accessible. */
8771 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8773 /* Set FLD to the first private/protected member of the class. */
8774 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8776 /* The warning format string. */
8777 const char *warnfmt
= NULL
;
8778 /* A suggested alternative to offer instead of the raw memory call.
8779 Empty string when none can be come up with. */
8780 const char *suggest
= "";
8781 bool warned
= false;
8783 switch (DECL_FUNCTION_CODE (fndecl
))
8785 case BUILT_IN_MEMSET
:
8786 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8788 /* Diagnose setting non-copy-assignable or non-trivial types,
8789 or types with a private member, to (potentially) non-zero
8790 bytes. Since the value of the bytes being written is unknown,
8791 suggest using assignment instead (if one exists). Also warn
8792 for writes into objects for which zero-initialization doesn't
8793 mean all bits clear (pointer-to-member data, where null is all
8794 bits set). Since the value being written is (most likely)
8795 non-zero, simply suggest assignment (but not copy assignment). */
8796 suggest
= "; use assignment instead";
8798 warnfmt
= G_("%qD writing to an object of type %#qT with "
8799 "no trivial copy-assignment");
8801 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8804 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8805 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8806 "%qD writing to an object of type %#qT with "
8808 fndecl
, desttype
, access
, fld
);
8810 else if (!zero_init_p (desttype
))
8811 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8812 "a pointer to data member%s");
8818 case BUILT_IN_BZERO
:
8819 /* Similarly to the above, diagnose clearing non-trivial or non-
8820 standard layout objects, or objects of types with no assignmenmt.
8821 Since the value being written is known to be zero, suggest either
8822 copy assignment, copy ctor, or default ctor as an alternative,
8823 depending on what's available. */
8825 if (hasassign
&& hasctors
[0])
8826 suggest
= G_("; use assignment or value-initialization instead");
8828 suggest
= G_("; use assignment instead");
8829 else if (hasctors
[0])
8830 suggest
= G_("; use value-initialization instead");
8833 warnfmt
= G_("%qD clearing an object of type %#qT with "
8834 "no trivial copy-assignment%s");
8836 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8837 else if (!zero_init_p (desttype
))
8838 warnfmt
= G_("%qD clearing an object of type %#qT containing "
8839 "a pointer-to-member%s");
8842 case BUILT_IN_BCOPY
:
8843 case BUILT_IN_MEMCPY
:
8844 case BUILT_IN_MEMMOVE
:
8845 case BUILT_IN_MEMPCPY
:
8846 /* Determine the type of the source object. */
8847 srctype
= TREE_TYPE ((*args
)[srcidx
]);
8848 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
8849 srctype
= void_type_node
;
8851 srctype
= TREE_TYPE (srctype
);
8853 /* Since it's impossible to determine wheter the byte copy is
8854 being used in place of assignment to an existing object or
8855 as a substitute for initialization, assume it's the former.
8856 Determine the best alternative to use instead depending on
8857 what's not deleted. */
8858 if (hasassign
&& hasctors
[1])
8859 suggest
= G_("; use copy-assignment or copy-initialization instead");
8861 suggest
= G_("; use copy-assignment instead");
8862 else if (hasctors
[1])
8863 suggest
= G_("; use copy-initialization instead");
8866 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
8867 "copy-assignment%s");
8868 else if (!trivially_copyable_p (desttype
))
8869 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
8872 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
8875 && !VOID_TYPE_P (srctype
)
8876 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8877 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8880 /* Warn when copying into a non-trivial object from an object
8881 of a different type other than void or char. */
8882 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8883 "%qD copying an object of non-trivial type "
8884 "%#qT from an array of %#qT",
8885 fndecl
, desttype
, srctype
);
8888 && !VOID_TYPE_P (srctype
)
8889 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8890 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8893 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8894 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8895 "%qD copying an object of type %#qT with "
8896 "%qs member %qD from an array of %#qT; use "
8897 "assignment or copy-initialization instead",
8898 fndecl
, desttype
, access
, fld
, srctype
);
8900 else if (!trivial
&& vec_safe_length (args
) > 2)
8902 tree sz
= maybe_constant_value ((*args
)[2]);
8903 if (!tree_fits_uhwi_p (sz
))
8906 /* Finally, warn on partial copies. */
8907 unsigned HOST_WIDE_INT typesize
8908 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
8909 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
8910 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8911 (typesize
- partial
> 1
8912 ? G_("%qD writing to an object of "
8913 "a non-trivial type %#qT leaves %wu "
8915 : G_("%qD writing to an object of "
8916 "a non-trivial type %#qT leaves %wu "
8918 fndecl
, desttype
, typesize
- partial
);
8922 case BUILT_IN_REALLOC
:
8924 if (!trivially_copyable_p (desttype
))
8925 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
8926 "%#qT; use %<new%> and %<delete%> instead");
8928 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
8929 "constructor; use %<new%> and %<delete%> instead");
8930 else if (!get_dtor (desttype
, tf_none
))
8931 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
8935 tree sz
= maybe_constant_value ((*args
)[1]);
8936 if (TREE_CODE (sz
) == INTEGER_CST
8937 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
8938 /* Finally, warn on reallocation into insufficient space. */
8939 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8940 "%qD moving an object of non-trivial type "
8941 "%#qT and size %E into a region of size %E",
8942 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
8954 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8955 warnfmt
, fndecl
, desttype
, suggest
);
8957 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8958 warnfmt
, fndecl
, desttype
);
8962 inform (location_of (desttype
), "%#qT declared here", desttype
);
8965 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
8966 This function performs no overload resolution, conversion, or other
8967 high-level operations. */
8970 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
8971 tsubst_flags_t complain
)
8975 /* Remember roughly where this call is. */
8976 location_t loc
= cp_expr_loc_or_loc (fn
, input_location
);
8977 fn
= build_call_a (fn
, nargs
, argarray
);
8978 SET_EXPR_LOCATION (fn
, loc
);
8980 fndecl
= get_callee_fndecl (fn
);
8982 /* Check that arguments to builtin functions match the expectations. */
8984 && !processing_template_decl
8985 && fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
8989 /* We need to take care that values to BUILT_IN_NORMAL
8991 for (i
= 0; i
< nargs
; i
++)
8992 argarray
[i
] = maybe_constant_value (argarray
[i
]);
8994 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
8996 return error_mark_node
;
8999 if (VOID_TYPE_P (TREE_TYPE (fn
)))
9002 /* 5.2.2/11: If a function call is a prvalue of object type: if the
9003 function call is either the operand of a decltype-specifier or the
9004 right operand of a comma operator that is the operand of a
9005 decltype-specifier, a temporary object is not introduced for the
9006 prvalue. The type of the prvalue may be incomplete. */
9007 if (!(complain
& tf_decltype
))
9009 fn
= require_complete_type_sfinae (fn
, complain
);
9010 if (fn
== error_mark_node
)
9011 return error_mark_node
;
9013 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9015 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9016 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9019 return convert_from_reference (fn
);
9022 /* Returns the value to use for the in-charge parameter when making a
9023 call to a function with the indicated NAME.
9025 FIXME:Can't we find a neater way to do this mapping? */
9028 in_charge_arg_for_name (tree name
)
9030 if (IDENTIFIER_CTOR_P (name
))
9032 if (name
== complete_ctor_identifier
)
9033 return integer_one_node
;
9034 gcc_checking_assert (name
== base_ctor_identifier
);
9038 if (name
== complete_dtor_identifier
)
9039 return integer_two_node
;
9040 else if (name
== deleting_dtor_identifier
)
9041 return integer_three_node
;
9042 gcc_checking_assert (name
== base_dtor_identifier
);
9045 return integer_zero_node
;
9048 /* We've built up a constructor call RET. Complain if it delegates to the
9049 constructor we're currently compiling. */
9052 check_self_delegation (tree ret
)
9054 if (TREE_CODE (ret
) == TARGET_EXPR
)
9055 ret
= TARGET_EXPR_INITIAL (ret
);
9056 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9057 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9058 error ("constructor delegates to itself");
9061 /* Build a call to a constructor, destructor, or an assignment
9062 operator for INSTANCE, an expression with class type. NAME
9063 indicates the special member function to call; *ARGS are the
9064 arguments. ARGS may be NULL. This may change ARGS. BINFO
9065 indicates the base of INSTANCE that is to be passed as the `this'
9066 parameter to the member function called.
9068 FLAGS are the LOOKUP_* flags to use when processing the call.
9070 If NAME indicates a complete object constructor, INSTANCE may be
9071 NULL_TREE. In this case, the caller will call build_cplus_new to
9072 store the newly constructed object into a VAR_DECL. */
9075 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9076 tree binfo
, int flags
, tsubst_flags_t complain
)
9079 /* The type of the subobject to be constructed or destroyed. */
9081 vec
<tree
, va_gc
> *allocated
= NULL
;
9084 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9086 if (error_operand_p (instance
))
9087 return error_mark_node
;
9089 if (IDENTIFIER_DTOR_P (name
))
9091 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9092 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9093 /* Shortcut to avoid lazy destructor declaration. */
9094 return build_trivial_dtor_call (instance
);
9099 /* Resolve the name. */
9100 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9101 return error_mark_node
;
9103 binfo
= TYPE_BINFO (binfo
);
9106 gcc_assert (binfo
!= NULL_TREE
);
9108 class_type
= BINFO_TYPE (binfo
);
9110 /* Handle the special case where INSTANCE is NULL_TREE. */
9111 if (name
== complete_ctor_identifier
&& !instance
)
9112 instance
= build_dummy_object (class_type
);
9115 /* Convert to the base class, if necessary. */
9116 if (!same_type_ignoring_top_level_qualifiers_p
9117 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9119 if (IDENTIFIER_CDTOR_P (name
))
9120 /* For constructors and destructors, either the base is
9121 non-virtual, or it is virtual but we are doing the
9122 conversion from a constructor or destructor for the
9123 complete object. In either case, we can convert
9125 instance
= convert_to_base_statically (instance
, binfo
);
9128 /* However, for assignment operators, we must convert
9129 dynamically if the base is virtual. */
9130 gcc_checking_assert (name
== assign_op_identifier
);
9131 instance
= build_base_path (PLUS_EXPR
, instance
,
9132 binfo
, /*nonnull=*/1, complain
);
9137 gcc_assert (instance
!= NULL_TREE
);
9139 /* In C++17, "If the initializer expression is a prvalue and the
9140 cv-unqualified version of the source type is the same class as the class
9141 of the destination, the initializer expression is used to initialize the
9142 destination object." Handle that here to avoid doing overload
9144 if (cxx_dialect
>= cxx17
9145 && args
&& vec_safe_length (*args
) == 1
9146 && name
== complete_ctor_identifier
)
9148 tree arg
= (**args
)[0];
9150 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9151 && !TYPE_HAS_LIST_CTOR (class_type
)
9152 && CONSTRUCTOR_NELTS (arg
) == 1)
9153 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9155 if ((TREE_CODE (arg
) == TARGET_EXPR
9156 || TREE_CODE (arg
) == CONSTRUCTOR
)
9157 && (same_type_ignoring_top_level_qualifiers_p
9158 (class_type
, TREE_TYPE (arg
))))
9160 if (is_dummy_object (instance
))
9162 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9163 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9165 if ((complain
& tf_error
)
9166 && (flags
& LOOKUP_DELEGATING_CONS
))
9167 check_self_delegation (arg
);
9168 /* Avoid change of behavior on Wunused-var-2.C. */
9169 instance
= mark_lvalue_use (instance
);
9170 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9174 fns
= lookup_fnfields (binfo
, name
, 1);
9176 /* When making a call to a constructor or destructor for a subobject
9177 that uses virtual base classes, pass down a pointer to a VTT for
9179 if ((name
== base_ctor_identifier
9180 || name
== base_dtor_identifier
)
9181 && CLASSTYPE_VBASECLASSES (class_type
))
9186 /* If the current function is a complete object constructor
9187 or destructor, then we fetch the VTT directly.
9188 Otherwise, we look it up using the VTT we were given. */
9189 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9190 vtt
= decay_conversion (vtt
, complain
);
9191 if (vtt
== error_mark_node
)
9192 return error_mark_node
;
9193 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9194 if (BINFO_SUBVTT_INDEX (binfo
))
9195 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9201 allocated
= make_tree_vector ();
9205 vec_safe_insert (*args
, 0, sub_vtt
);
9208 ret
= build_new_method_call (instance
, fns
, args
,
9209 TYPE_BINFO (BINFO_TYPE (binfo
)),
9213 if (allocated
!= NULL
)
9214 release_tree_vector (allocated
);
9216 if ((complain
& tf_error
)
9217 && (flags
& LOOKUP_DELEGATING_CONS
)
9218 && name
== complete_ctor_identifier
)
9219 check_self_delegation (ret
);
9224 /* Return the NAME, as a C string. The NAME indicates a function that
9225 is a member of TYPE. *FREE_P is set to true if the caller must
9226 free the memory returned.
9228 Rather than go through all of this, we should simply set the names
9229 of constructors and destructors appropriately, and dispense with
9230 ctor_identifier, dtor_identifier, etc. */
9233 name_as_c_string (tree name
, tree type
, bool *free_p
)
9235 const char *pretty_name
;
9237 /* Assume that we will not allocate memory. */
9239 /* Constructors and destructors are special. */
9240 if (IDENTIFIER_CDTOR_P (name
))
9243 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9244 /* For a destructor, add the '~'. */
9245 if (IDENTIFIER_DTOR_P (name
))
9247 pretty_name
= concat ("~", pretty_name
, NULL
);
9248 /* Remember that we need to free the memory allocated. */
9252 else if (IDENTIFIER_CONV_OP_P (name
))
9254 pretty_name
= concat ("operator ",
9255 type_as_string_translate (TREE_TYPE (name
),
9256 TFF_PLAIN_IDENTIFIER
),
9258 /* Remember that we need to free the memory allocated. */
9262 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9264 return CONST_CAST (char *, pretty_name
);
9267 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9270 static z_candidate
*
9271 single_z_candidate (z_candidate
*candidates
)
9273 if (candidates
== NULL
)
9276 if (candidates
->next
)
9282 /* If CANDIDATE is invalid due to a bad argument type, return the
9283 pertinent conversion_info.
9285 Otherwise, return NULL. */
9287 static const conversion_info
*
9288 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9290 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9291 rejection_reason
*r
= candidate
->reason
;
9301 case rr_arg_conversion
:
9302 return &r
->u
.conversion
;
9304 case rr_bad_arg_conversion
:
9305 return &r
->u
.bad_conversion
;
9309 /* Issue an error and note complaining about a bad argument type at a
9310 callsite with a single candidate FNDECL.
9312 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9313 case input_location is used).
9314 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9315 the formal parameter. */
9318 complain_about_bad_argument (location_t arg_loc
,
9319 tree from_type
, tree to_type
,
9320 tree fndecl
, int parmnum
)
9322 auto_diagnostic_group d
;
9323 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9324 range_label
*label
= &rhs_label
;
9325 if (arg_loc
== UNKNOWN_LOCATION
)
9327 arg_loc
= input_location
;
9330 gcc_rich_location
richloc (arg_loc
, label
);
9332 "cannot convert %qH to %qI",
9333 from_type
, to_type
);
9334 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9338 /* Subroutine of build_new_method_call_1, for where there are no viable
9339 candidates for the call. */
9342 complain_about_no_candidates_for_method_call (tree instance
,
9343 z_candidate
*candidates
,
9344 tree explicit_targs
,
9346 tree optype
, tree name
,
9347 bool skip_first_for_error
,
9348 vec
<tree
, va_gc
> *user_args
)
9350 auto_diagnostic_group d
;
9351 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9352 cxx_incomplete_type_error (instance
, basetype
);
9354 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9355 basetype
, optype
, build_tree_list_vec (user_args
),
9356 TREE_TYPE (instance
));
9359 /* Special-case for when there's a single candidate that's failing
9360 due to a bad argument type. */
9361 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9362 if (const conversion_info
*conv
9363 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9365 complain_about_bad_argument (conv
->loc
,
9366 conv
->from
, conv
->to_type
,
9367 candidate
->fn
, conv
->n_arg
);
9371 tree arglist
= build_tree_list_vec (user_args
);
9372 tree errname
= name
;
9373 bool twiddle
= false;
9374 if (IDENTIFIER_CDTOR_P (errname
))
9376 twiddle
= IDENTIFIER_DTOR_P (errname
);
9377 errname
= constructor_name (basetype
);
9380 errname
= lookup_template_function (errname
, explicit_targs
);
9381 if (skip_first_for_error
)
9382 arglist
= TREE_CHAIN (arglist
);
9383 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9384 basetype
, &"~"[!twiddle
], errname
, arglist
,
9385 TREE_TYPE (instance
));
9387 print_z_candidates (location_of (name
), candidates
);
9390 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9391 be set, upon return, to the function called. ARGS may be NULL.
9392 This may change ARGS. */
9395 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9396 tree conversion_path
, int flags
,
9397 tree
*fn_p
, tsubst_flags_t complain
)
9399 struct z_candidate
*candidates
= 0, *cand
;
9400 tree explicit_targs
= NULL_TREE
;
9401 tree basetype
= NULL_TREE
;
9402 tree access_binfo
, binfo
;
9404 tree first_mem_arg
= NULL_TREE
;
9406 bool skip_first_for_error
;
9407 vec
<tree
, va_gc
> *user_args
;
9410 int template_only
= 0;
9414 vec
<tree
, va_gc
> *orig_args
= NULL
;
9417 gcc_assert (instance
!= NULL_TREE
);
9419 /* We don't know what function we're going to call, yet. */
9423 if (error_operand_p (instance
)
9424 || !fns
|| error_operand_p (fns
))
9425 return error_mark_node
;
9427 if (!BASELINK_P (fns
))
9429 if (complain
& tf_error
)
9430 error ("call to non-function %qD", fns
);
9431 return error_mark_node
;
9434 orig_instance
= instance
;
9437 /* Dismantle the baselink to collect all the information we need. */
9438 if (!conversion_path
)
9439 conversion_path
= BASELINK_BINFO (fns
);
9440 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9441 binfo
= BASELINK_BINFO (fns
);
9442 optype
= BASELINK_OPTYPE (fns
);
9443 fns
= BASELINK_FUNCTIONS (fns
);
9444 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9446 explicit_targs
= TREE_OPERAND (fns
, 1);
9447 fns
= TREE_OPERAND (fns
, 0);
9450 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
9451 || TREE_CODE (fns
) == TEMPLATE_DECL
9452 || TREE_CODE (fns
) == OVERLOAD
);
9453 fn
= OVL_FIRST (fns
);
9454 name
= DECL_NAME (fn
);
9456 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9457 gcc_assert (CLASS_TYPE_P (basetype
));
9459 user_args
= args
== NULL
? NULL
: *args
;
9460 /* Under DR 147 A::A() is an invalid constructor call,
9461 not a functional cast. */
9462 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9464 if (! (complain
& tf_error
))
9465 return error_mark_node
;
9467 basetype
= DECL_CONTEXT (fn
);
9468 name
= constructor_name (basetype
);
9469 auto_diagnostic_group d
;
9470 if (permerror (input_location
,
9471 "cannot call constructor %<%T::%D%> directly",
9473 inform (input_location
, "for a function-style cast, remove the "
9474 "redundant %<::%D%>", name
);
9475 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9480 if (processing_template_decl
)
9482 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9483 instance
= build_non_dependent_expr (instance
);
9485 make_args_non_dependent (*args
);
9488 /* Process the argument list. */
9489 if (args
!= NULL
&& *args
!= NULL
)
9491 *args
= resolve_args (*args
, complain
);
9493 return error_mark_node
;
9497 /* Consider the object argument to be used even if we end up selecting a
9498 static member function. */
9499 instance
= mark_type_use (instance
);
9501 /* Figure out whether to skip the first argument for the error
9502 message we will display to users if an error occurs. We don't
9503 want to display any compiler-generated arguments. The "this"
9504 pointer hasn't been added yet. However, we must remove the VTT
9505 pointer if this is a call to a base-class constructor or
9507 skip_first_for_error
= false;
9508 if (IDENTIFIER_CDTOR_P (name
))
9510 /* Callers should explicitly indicate whether they want to ctor
9511 the complete object or just the part without virtual bases. */
9512 gcc_assert (name
!= ctor_identifier
);
9514 /* Remove the VTT pointer, if present. */
9515 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9516 && CLASSTYPE_VBASECLASSES (basetype
))
9517 skip_first_for_error
= true;
9519 /* It's OK to call destructors and constructors on cv-qualified
9520 objects. Therefore, convert the INSTANCE to the unqualified
9521 type, if necessary. */
9522 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9524 instance
= build_this (instance
);
9525 instance
= build_nop (build_pointer_type (basetype
), instance
);
9526 instance
= build_fold_indirect_ref (instance
);
9530 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9532 /* For the overload resolution we need to find the actual `this`
9533 that would be captured if the call turns out to be to a
9534 non-static member function. Do not actually capture it at this
9536 if (DECL_CONSTRUCTOR_P (fn
))
9537 /* Constructors don't use the enclosing 'this'. */
9538 first_mem_arg
= instance
;
9540 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9542 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9543 p
= conversion_obstack_alloc (0);
9545 /* The number of arguments artificial parms in ARGS; we subtract one because
9546 there's no 'this' in ARGS. */
9547 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9549 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9550 initializer, not T({ }). */
9551 if (DECL_CONSTRUCTOR_P (fn
)
9552 && vec_safe_length (user_args
) > skip
9553 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9555 tree init_list
= (*user_args
)[skip
];
9556 tree init
= NULL_TREE
;
9558 gcc_assert (user_args
->length () == skip
+ 1
9559 && !(flags
& LOOKUP_ONLYCONVERTING
));
9561 /* If the initializer list has no elements and T is a class type with
9562 a default constructor, the object is value-initialized. Handle
9563 this here so we don't need to handle it wherever we use
9564 build_special_member_call. */
9565 if (CONSTRUCTOR_NELTS (init_list
) == 0
9566 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9567 /* For a user-provided default constructor, use the normal
9568 mechanisms so that protected access works. */
9569 && type_has_non_user_provided_default_constructor (basetype
)
9570 && !processing_template_decl
)
9571 init
= build_value_init (basetype
, complain
);
9573 /* If BASETYPE is an aggregate, we need to do aggregate
9575 else if (CP_AGGREGATE_TYPE_P (basetype
))
9577 init
= reshape_init (basetype
, init_list
, complain
);
9578 init
= digest_init (basetype
, init
, complain
);
9583 if (is_dummy_object (instance
))
9584 return get_target_expr_sfinae (init
, complain
);
9585 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9586 TREE_SIDE_EFFECTS (init
) = true;
9590 /* Otherwise go ahead with overload resolution. */
9591 add_list_candidates (fns
, first_mem_arg
, user_args
,
9592 basetype
, explicit_targs
, template_only
,
9593 conversion_path
, access_binfo
, flags
,
9594 &candidates
, complain
);
9597 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9598 explicit_targs
, template_only
, conversion_path
,
9599 access_binfo
, flags
, &candidates
, complain
);
9601 any_viable_p
= false;
9602 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9606 if (complain
& tf_error
)
9607 complain_about_no_candidates_for_method_call (instance
, candidates
,
9608 explicit_targs
, basetype
,
9610 skip_first_for_error
,
9612 call
= error_mark_node
;
9616 cand
= tourney (candidates
, complain
);
9623 if (complain
& tf_error
)
9625 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9626 arglist
= build_tree_list_vec (user_args
);
9627 if (skip_first_for_error
)
9628 arglist
= TREE_CHAIN (arglist
);
9629 auto_diagnostic_group d
;
9630 if (!any_strictly_viable (candidates
))
9631 error ("no matching function for call to %<%s(%A)%>",
9632 pretty_name
, arglist
);
9634 error ("call of overloaded %<%s(%A)%> is ambiguous",
9635 pretty_name
, arglist
);
9636 print_z_candidates (location_of (name
), candidates
);
9640 call
= error_mark_node
;
9647 if (!(flags
& LOOKUP_NONVIRTUAL
)
9648 && DECL_PURE_VIRTUAL_P (fn
)
9649 && instance
== current_class_ref
9650 && (complain
& tf_warning
))
9652 /* This is not an error, it is runtime undefined
9654 if (!current_function_decl
)
9655 warning (0, "pure virtual %q#D called from "
9656 "non-static data member initializer", fn
);
9657 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9658 || DECL_DESTRUCTOR_P (current_function_decl
))
9659 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9660 ? G_("pure virtual %q#D called from constructor")
9661 : G_("pure virtual %q#D called from destructor")),
9665 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9666 && !DECL_CONSTRUCTOR_P (fn
)
9667 && is_dummy_object (instance
))
9669 instance
= maybe_resolve_dummy (instance
, true);
9670 if (instance
== error_mark_node
)
9671 call
= error_mark_node
;
9672 else if (!is_dummy_object (instance
))
9674 /* We captured 'this' in the current lambda now that
9675 we know we really need it. */
9676 cand
->first_arg
= instance
;
9678 else if (any_dependent_bases_p ())
9679 /* We can't tell until instantiation time whether we can use
9680 *this as the implicit object argument. */;
9683 if (complain
& tf_error
)
9684 error ("cannot call member function %qD without object",
9686 call
= error_mark_node
;
9690 if (call
!= error_mark_node
)
9692 /* Optimize away vtable lookup if we know that this
9693 function can't be overridden. We need to check if
9694 the context and the type where we found fn are the same,
9695 actually FN might be defined in a different class
9696 type because of a using-declaration. In this case, we
9697 do not want to perform a non-virtual call. */
9698 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9699 && same_type_ignoring_top_level_qualifiers_p
9700 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9701 && resolves_to_fixed_type_p (instance
, 0))
9702 flags
|= LOOKUP_NONVIRTUAL
;
9704 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9705 /* Now we know what function is being called. */
9708 /* Build the actual CALL_EXPR. */
9709 call
= build_over_call (cand
, flags
, complain
);
9710 /* In an expression of the form `a->f()' where `f' turns
9711 out to be a static member function, `a' is
9712 none-the-less evaluated. */
9713 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9714 && !is_dummy_object (instance
)
9715 && TREE_SIDE_EFFECTS (instance
))
9717 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9720 if (TREE_THIS_VOLATILE (a
))
9722 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9724 else if (call
!= error_mark_node
9725 && DECL_DESTRUCTOR_P (cand
->fn
)
9726 && !VOID_TYPE_P (TREE_TYPE (call
)))
9727 /* An explicit call of the form "x->~X()" has type
9728 "void". However, on platforms where destructors
9729 return "this" (i.e., those where
9730 targetm.cxx.cdtor_returns_this is true), such calls
9731 will appear to have a return value of pointer type
9732 to the low-level call machinery. We do not want to
9733 change the low-level machinery, since we want to be
9734 able to optimize "delete f()" on such platforms as
9735 "operator delete(~X(f()))" (rather than generating
9736 "t = f(), ~X(t), operator delete (t)"). */
9737 call
= build_nop (void_type_node
, call
);
9742 if (processing_template_decl
&& call
!= error_mark_node
)
9744 bool cast_to_void
= false;
9746 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9747 call
= TREE_OPERAND (call
, 1);
9748 else if (TREE_CODE (call
) == NOP_EXPR
)
9750 cast_to_void
= true;
9751 call
= TREE_OPERAND (call
, 0);
9753 if (INDIRECT_REF_P (call
))
9754 call
= TREE_OPERAND (call
, 0);
9755 call
= (build_min_non_dep_call_vec
9757 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9758 orig_instance
, orig_fns
, NULL_TREE
),
9760 SET_EXPR_LOCATION (call
, input_location
);
9761 call
= convert_from_reference (call
);
9763 call
= build_nop (void_type_node
, call
);
9766 /* Free all the conversions we allocated. */
9767 obstack_free (&conversion_obstack
, p
);
9769 if (orig_args
!= NULL
)
9770 release_tree_vector (orig_args
);
9775 /* Wrapper for above. */
9778 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9779 tree conversion_path
, int flags
,
9780 tree
*fn_p
, tsubst_flags_t complain
)
9783 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9784 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9786 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9790 /* Returns true iff standard conversion sequence ICS1 is a proper
9791 subsequence of ICS2. */
9794 is_subseq (conversion
*ics1
, conversion
*ics2
)
9796 /* We can assume that a conversion of the same code
9797 between the same types indicates a subsequence since we only get
9798 here if the types we are converting from are the same. */
9800 while (ics1
->kind
== ck_rvalue
9801 || ics1
->kind
== ck_lvalue
)
9802 ics1
= next_conversion (ics1
);
9806 while (ics2
->kind
== ck_rvalue
9807 || ics2
->kind
== ck_lvalue
)
9808 ics2
= next_conversion (ics2
);
9810 if (ics2
->kind
== ck_user
9811 || ics2
->kind
== ck_ambig
9812 || ics2
->kind
== ck_aggr
9813 || ics2
->kind
== ck_list
9814 || ics2
->kind
== ck_identity
)
9815 /* At this point, ICS1 cannot be a proper subsequence of
9816 ICS2. We can get a USER_CONV when we are comparing the
9817 second standard conversion sequence of two user conversion
9821 ics2
= next_conversion (ics2
);
9823 while (ics2
->kind
== ck_rvalue
9824 || ics2
->kind
== ck_lvalue
)
9825 ics2
= next_conversion (ics2
);
9827 if (ics2
->kind
== ics1
->kind
9828 && same_type_p (ics2
->type
, ics1
->type
)
9829 && (ics1
->kind
== ck_identity
9830 || same_type_p (next_conversion (ics2
)->type
,
9831 next_conversion (ics1
)->type
)))
9836 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9837 be any _TYPE nodes. */
9840 is_properly_derived_from (tree derived
, tree base
)
9842 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
9845 /* We only allow proper derivation here. The DERIVED_FROM_P macro
9846 considers every class derived from itself. */
9847 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
9848 && DERIVED_FROM_P (base
, derived
));
9851 /* We build the ICS for an implicit object parameter as a pointer
9852 conversion sequence. However, such a sequence should be compared
9853 as if it were a reference conversion sequence. If ICS is the
9854 implicit conversion sequence for an implicit object parameter,
9855 modify it accordingly. */
9858 maybe_handle_implicit_object (conversion
**ics
)
9862 /* [over.match.funcs]
9864 For non-static member functions, the type of the
9865 implicit object parameter is "reference to cv X"
9866 where X is the class of which the function is a
9867 member and cv is the cv-qualification on the member
9868 function declaration. */
9869 conversion
*t
= *ics
;
9870 tree reference_type
;
9872 /* The `this' parameter is a pointer to a class type. Make the
9873 implicit conversion talk about a reference to that same class
9875 reference_type
= TREE_TYPE (t
->type
);
9876 reference_type
= build_reference_type (reference_type
);
9878 if (t
->kind
== ck_qual
)
9879 t
= next_conversion (t
);
9880 if (t
->kind
== ck_ptr
)
9881 t
= next_conversion (t
);
9882 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
9883 t
= direct_reference_binding (reference_type
, t
);
9885 t
->rvaluedness_matches_p
= 0;
9890 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
9891 and return the initial reference binding conversion. Otherwise,
9892 leave *ICS unchanged and return NULL. */
9895 maybe_handle_ref_bind (conversion
**ics
)
9897 if ((*ics
)->kind
== ck_ref_bind
)
9899 conversion
*old_ics
= *ics
;
9900 *ics
= next_conversion (old_ics
);
9901 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
9908 /* Compare two implicit conversion sequences according to the rules set out in
9909 [over.ics.rank]. Return values:
9911 1: ics1 is better than ics2
9912 -1: ics2 is better than ics1
9913 0: ics1 and ics2 are indistinguishable */
9916 compare_ics (conversion
*ics1
, conversion
*ics2
)
9922 tree deref_from_type1
= NULL_TREE
;
9923 tree deref_from_type2
= NULL_TREE
;
9924 tree deref_to_type1
= NULL_TREE
;
9925 tree deref_to_type2
= NULL_TREE
;
9926 conversion_rank rank1
, rank2
;
9928 /* REF_BINDING is nonzero if the result of the conversion sequence
9929 is a reference type. In that case REF_CONV is the reference
9930 binding conversion. */
9931 conversion
*ref_conv1
;
9932 conversion
*ref_conv2
;
9934 /* Compare badness before stripping the reference conversion. */
9935 if (ics1
->bad_p
> ics2
->bad_p
)
9937 else if (ics1
->bad_p
< ics2
->bad_p
)
9940 /* Handle implicit object parameters. */
9941 maybe_handle_implicit_object (&ics1
);
9942 maybe_handle_implicit_object (&ics2
);
9944 /* Handle reference parameters. */
9945 ref_conv1
= maybe_handle_ref_bind (&ics1
);
9946 ref_conv2
= maybe_handle_ref_bind (&ics2
);
9948 /* List-initialization sequence L1 is a better conversion sequence than
9949 list-initialization sequence L2 if L1 converts to
9950 std::initializer_list<X> for some X and L2 does not. */
9951 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
9953 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
9958 When comparing the basic forms of implicit conversion sequences (as
9959 defined in _over.best.ics_)
9961 --a standard conversion sequence (_over.ics.scs_) is a better
9962 conversion sequence than a user-defined conversion sequence
9963 or an ellipsis conversion sequence, and
9965 --a user-defined conversion sequence (_over.ics.user_) is a
9966 better conversion sequence than an ellipsis conversion sequence
9967 (_over.ics.ellipsis_). */
9968 /* Use BAD_CONVERSION_RANK because we already checked for a badness
9969 mismatch. If both ICS are bad, we try to make a decision based on
9970 what would have happened if they'd been good. This is not an
9971 extension, we'll still give an error when we build up the call; this
9972 just helps us give a more helpful error message. */
9973 rank1
= BAD_CONVERSION_RANK (ics1
);
9974 rank2
= BAD_CONVERSION_RANK (ics2
);
9978 else if (rank1
< rank2
)
9981 if (ics1
->ellipsis_p
)
9982 /* Both conversions are ellipsis conversions. */
9985 /* User-defined conversion sequence U1 is a better conversion sequence
9986 than another user-defined conversion sequence U2 if they contain the
9987 same user-defined conversion operator or constructor and if the sec-
9988 ond standard conversion sequence of U1 is better than the second
9989 standard conversion sequence of U2. */
9991 /* Handle list-conversion with the same code even though it isn't always
9992 ranked as a user-defined conversion and it doesn't have a second
9993 standard conversion sequence; it will still have the desired effect.
9994 Specifically, we need to do the reference binding comparison at the
9995 end of this function. */
9997 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
|| ics1
->kind
== ck_aggr
)
10002 for (t1
= ics1
; t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
10003 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
10004 || t1
->kind
== ck_list
)
10006 for (t2
= ics2
; t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
10007 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
10008 || t2
->kind
== ck_list
)
10011 if (t1
->kind
!= t2
->kind
)
10013 else if (t1
->kind
== ck_user
)
10015 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10016 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10022 /* For ambiguous or aggregate conversions, use the target type as
10023 a proxy for the conversion function. */
10024 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10028 /* We can just fall through here, after setting up
10029 FROM_TYPE1 and FROM_TYPE2. */
10030 from_type1
= t1
->type
;
10031 from_type2
= t2
->type
;
10038 /* We're dealing with two standard conversion sequences.
10042 Standard conversion sequence S1 is a better conversion
10043 sequence than standard conversion sequence S2 if
10045 --S1 is a proper subsequence of S2 (comparing the conversion
10046 sequences in the canonical form defined by _over.ics.scs_,
10047 excluding any Lvalue Transformation; the identity
10048 conversion sequence is considered to be a subsequence of
10049 any non-identity conversion sequence */
10052 while (t1
->kind
!= ck_identity
)
10053 t1
= next_conversion (t1
);
10054 from_type1
= t1
->type
;
10057 while (t2
->kind
!= ck_identity
)
10058 t2
= next_conversion (t2
);
10059 from_type2
= t2
->type
;
10062 /* One sequence can only be a subsequence of the other if they start with
10063 the same type. They can start with different types when comparing the
10064 second standard conversion sequence in two user-defined conversion
10066 if (same_type_p (from_type1
, from_type2
))
10068 if (is_subseq (ics1
, ics2
))
10070 if (is_subseq (ics2
, ics1
))
10078 --the rank of S1 is better than the rank of S2 (by the rules
10081 Standard conversion sequences are ordered by their ranks: an Exact
10082 Match is a better conversion than a Promotion, which is a better
10083 conversion than a Conversion.
10085 Two conversion sequences with the same rank are indistinguishable
10086 unless one of the following rules applies:
10088 --A conversion that does not a convert a pointer, pointer to member,
10089 or std::nullptr_t to bool is better than one that does.
10091 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10092 so that we do not have to check it explicitly. */
10093 if (ics1
->rank
< ics2
->rank
)
10095 else if (ics2
->rank
< ics1
->rank
)
10098 to_type1
= ics1
->type
;
10099 to_type2
= ics2
->type
;
10101 /* A conversion from scalar arithmetic type to complex is worse than a
10102 conversion between scalar arithmetic types. */
10103 if (same_type_p (from_type1
, from_type2
)
10104 && ARITHMETIC_TYPE_P (from_type1
)
10105 && ARITHMETIC_TYPE_P (to_type1
)
10106 && ARITHMETIC_TYPE_P (to_type2
)
10107 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10108 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10110 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10116 if (TYPE_PTR_P (from_type1
)
10117 && TYPE_PTR_P (from_type2
)
10118 && TYPE_PTR_P (to_type1
)
10119 && TYPE_PTR_P (to_type2
))
10121 deref_from_type1
= TREE_TYPE (from_type1
);
10122 deref_from_type2
= TREE_TYPE (from_type2
);
10123 deref_to_type1
= TREE_TYPE (to_type1
);
10124 deref_to_type2
= TREE_TYPE (to_type2
);
10126 /* The rules for pointers to members A::* are just like the rules
10127 for pointers A*, except opposite: if B is derived from A then
10128 A::* converts to B::*, not vice versa. For that reason, we
10129 switch the from_ and to_ variables here. */
10130 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10131 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10132 || (TYPE_PTRMEMFUNC_P (from_type1
)
10133 && TYPE_PTRMEMFUNC_P (from_type2
)
10134 && TYPE_PTRMEMFUNC_P (to_type1
)
10135 && TYPE_PTRMEMFUNC_P (to_type2
)))
10137 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10138 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10139 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10140 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10143 if (deref_from_type1
!= NULL_TREE
10144 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10145 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10147 /* This was one of the pointer or pointer-like conversions.
10151 --If class B is derived directly or indirectly from class A,
10152 conversion of B* to A* is better than conversion of B* to
10153 void*, and conversion of A* to void* is better than
10154 conversion of B* to void*. */
10155 if (VOID_TYPE_P (deref_to_type1
)
10156 && VOID_TYPE_P (deref_to_type2
))
10158 if (is_properly_derived_from (deref_from_type1
,
10161 else if (is_properly_derived_from (deref_from_type2
,
10165 else if (VOID_TYPE_P (deref_to_type1
)
10166 || VOID_TYPE_P (deref_to_type2
))
10168 if (same_type_p (deref_from_type1
, deref_from_type2
))
10170 if (VOID_TYPE_P (deref_to_type2
))
10172 if (is_properly_derived_from (deref_from_type1
,
10176 /* We know that DEREF_TO_TYPE1 is `void' here. */
10177 else if (is_properly_derived_from (deref_from_type1
,
10182 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10183 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10187 --If class B is derived directly or indirectly from class A
10188 and class C is derived directly or indirectly from B,
10190 --conversion of C* to B* is better than conversion of C* to
10193 --conversion of B* to A* is better than conversion of C* to
10195 if (same_type_p (deref_from_type1
, deref_from_type2
))
10197 if (is_properly_derived_from (deref_to_type1
,
10200 else if (is_properly_derived_from (deref_to_type2
,
10204 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10206 if (is_properly_derived_from (deref_from_type2
,
10209 else if (is_properly_derived_from (deref_from_type1
,
10215 else if (CLASS_TYPE_P (non_reference (from_type1
))
10216 && same_type_p (from_type1
, from_type2
))
10218 tree from
= non_reference (from_type1
);
10222 --binding of an expression of type C to a reference of type
10223 B& is better than binding an expression of type C to a
10224 reference of type A&
10226 --conversion of C to B is better than conversion of C to A, */
10227 if (is_properly_derived_from (from
, to_type1
)
10228 && is_properly_derived_from (from
, to_type2
))
10230 if (is_properly_derived_from (to_type1
, to_type2
))
10232 else if (is_properly_derived_from (to_type2
, to_type1
))
10236 else if (CLASS_TYPE_P (non_reference (to_type1
))
10237 && same_type_p (to_type1
, to_type2
))
10239 tree to
= non_reference (to_type1
);
10243 --binding of an expression of type B to a reference of type
10244 A& is better than binding an expression of type C to a
10245 reference of type A&,
10247 --conversion of B to A is better than conversion of C to A */
10248 if (is_properly_derived_from (from_type1
, to
)
10249 && is_properly_derived_from (from_type2
, to
))
10251 if (is_properly_derived_from (from_type2
, from_type1
))
10253 else if (is_properly_derived_from (from_type1
, from_type2
))
10260 --S1 and S2 differ only in their qualification conversion and yield
10261 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10262 qualification signature of type T1 is a proper subset of the cv-
10263 qualification signature of type T2 */
10264 if (ics1
->kind
== ck_qual
10265 && ics2
->kind
== ck_qual
10266 && same_type_p (from_type1
, from_type2
))
10268 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10275 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10276 to an implicit object parameter of a non-static member function
10277 declared without a ref-qualifier, and either S1 binds an lvalue
10278 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10279 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10280 draft standard, 13.3.3.2)
10282 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10283 types to which the references refer are the same type except for
10284 top-level cv-qualifiers, and the type to which the reference
10285 initialized by S2 refers is more cv-qualified than the type to
10286 which the reference initialized by S1 refers.
10288 DR 1328 [over.match.best]: the context is an initialization by
10289 conversion function for direct reference binding (13.3.1.6) of a
10290 reference to function type, the return type of F1 is the same kind of
10291 reference (i.e. lvalue or rvalue) as the reference being initialized,
10292 and the return type of F2 is not. */
10294 if (ref_conv1
&& ref_conv2
)
10296 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10297 && (ref_conv1
->rvaluedness_matches_p
10298 != ref_conv2
->rvaluedness_matches_p
)
10299 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10300 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10301 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10303 if (ref_conv1
->bad_p
10304 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10305 TREE_TYPE (ref_conv2
->type
)))
10306 /* Don't prefer a bad conversion that drops cv-quals to a bad
10307 conversion with the wrong rvalueness. */
10309 return (ref_conv1
->rvaluedness_matches_p
10310 - ref_conv2
->rvaluedness_matches_p
);
10313 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10315 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10316 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10317 if (ref_conv1
->bad_p
)
10319 /* Prefer the one that drops fewer cv-quals. */
10320 tree ftype
= next_conversion (ref_conv1
)->type
;
10321 int fquals
= cp_type_quals (ftype
);
10325 return comp_cv_qualification (q2
, q1
);
10329 /* Neither conversion sequence is better than the other. */
10333 /* The source type for this standard conversion sequence. */
10336 source_type (conversion
*t
)
10338 for (;; t
= next_conversion (t
))
10340 if (t
->kind
== ck_user
10341 || t
->kind
== ck_ambig
10342 || t
->kind
== ck_identity
)
10345 gcc_unreachable ();
10348 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10349 a pointer to LOSER and re-running joust to produce the warning if WINNER
10350 is actually used. */
10353 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10355 candidate_warning
*cw
= (candidate_warning
*)
10356 conversion_obstack_alloc (sizeof (candidate_warning
));
10358 cw
->next
= winner
->warnings
;
10359 winner
->warnings
= cw
;
10362 /* Compare two candidates for overloading as described in
10363 [over.match.best]. Return values:
10365 1: cand1 is better than cand2
10366 -1: cand2 is better than cand1
10367 0: cand1 and cand2 are indistinguishable */
10370 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10371 tsubst_flags_t complain
)
10374 int off1
= 0, off2
= 0;
10378 /* Candidates that involve bad conversions are always worse than those
10380 if (cand1
->viable
> cand2
->viable
)
10382 if (cand1
->viable
< cand2
->viable
)
10385 /* If we have two pseudo-candidates for conversions to the same type,
10386 or two candidates for the same function, arbitrarily pick one. */
10387 if (cand1
->fn
== cand2
->fn
10388 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10391 /* Prefer a non-deleted function over an implicitly deleted move
10392 constructor or assignment operator. This differs slightly from the
10393 wording for issue 1402 (which says the move op is ignored by overload
10394 resolution), but this way produces better error messages. */
10395 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10396 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10397 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10399 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10400 && move_fn_p (cand1
->fn
))
10402 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10403 && move_fn_p (cand2
->fn
))
10407 /* a viable function F1
10408 is defined to be a better function than another viable function F2 if
10409 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10410 ICSi(F2), and then */
10412 /* for some argument j, ICSj(F1) is a better conversion sequence than
10415 /* For comparing static and non-static member functions, we ignore
10416 the implicit object parameter of the non-static function. The
10417 standard says to pretend that the static function has an object
10418 parm, but that won't work with operator overloading. */
10419 len
= cand1
->num_convs
;
10420 if (len
!= cand2
->num_convs
)
10422 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10423 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10425 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10426 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10427 /* We're comparing a near-match list constructor and a near-match
10428 non-list constructor. Just treat them as unordered. */
10431 gcc_assert (static_1
!= static_2
);
10442 for (i
= 0; i
< len
; ++i
)
10444 conversion
*t1
= cand1
->convs
[i
+ off1
];
10445 conversion
*t2
= cand2
->convs
[i
+ off2
];
10446 int comp
= compare_ics (t1
, t2
);
10450 if ((complain
& tf_warning
)
10452 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10453 == cr_std
+ cr_promotion
)
10454 && t1
->kind
== ck_std
10455 && t2
->kind
== ck_std
10456 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10457 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10458 && (TYPE_PRECISION (t1
->type
)
10459 == TYPE_PRECISION (t2
->type
))
10460 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10461 || (TREE_CODE (next_conversion (t1
)->type
)
10462 == ENUMERAL_TYPE
)))
10464 tree type
= next_conversion (t1
)->type
;
10466 struct z_candidate
*w
, *l
;
10468 type1
= t1
->type
, type2
= t2
->type
,
10469 w
= cand1
, l
= cand2
;
10471 type1
= t2
->type
, type2
= t1
->type
,
10472 w
= cand2
, l
= cand1
;
10476 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10477 type
, type1
, type2
);
10478 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10481 add_warning (w
, l
);
10484 if (winner
&& comp
!= winner
)
10493 /* warn about confusing overload resolution for user-defined conversions,
10494 either between a constructor and a conversion op, or between two
10496 if ((complain
& tf_warning
)
10497 && winner
&& warn_conversion
&& cand1
->second_conv
10498 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10499 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10501 struct z_candidate
*w
, *l
;
10502 bool give_warning
= false;
10505 w
= cand1
, l
= cand2
;
10507 w
= cand2
, l
= cand1
;
10509 /* We don't want to complain about `X::operator T1 ()'
10510 beating `X::operator T2 () const', when T2 is a no less
10511 cv-qualified version of T1. */
10512 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10513 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10515 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10516 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10518 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10523 if (!comp_ptr_ttypes (t
, f
))
10524 give_warning
= true;
10527 give_warning
= true;
10533 tree source
= source_type (w
->convs
[0]);
10534 if (INDIRECT_TYPE_P (source
))
10535 source
= TREE_TYPE (source
);
10536 auto_diagnostic_group d
;
10537 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10538 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10539 source
, w
->second_conv
->type
))
10541 inform (input_location
, " because conversion sequence for the argument is better");
10545 add_warning (w
, l
);
10551 /* DR 495 moved this tiebreaker above the template ones. */
10552 /* or, if not that,
10553 the context is an initialization by user-defined conversion (see
10554 _dcl.init_ and _over.match.user_) and the standard conversion
10555 sequence from the return type of F1 to the destination type (i.e.,
10556 the type of the entity being initialized) is a better conversion
10557 sequence than the standard conversion sequence from the return type
10558 of F2 to the destination type. */
10560 if (cand1
->second_conv
)
10562 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10567 /* or, if not that,
10568 F1 is a non-template function and F2 is a template function
10571 if (!cand1
->template_decl
&& cand2
->template_decl
)
10573 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10576 /* or, if not that,
10577 F1 and F2 are template functions and the function template for F1 is
10578 more specialized than the template for F2 according to the partial
10581 if (cand1
->template_decl
&& cand2
->template_decl
)
10583 winner
= more_specialized_fn
10584 (TI_TEMPLATE (cand1
->template_decl
),
10585 TI_TEMPLATE (cand2
->template_decl
),
10586 /* [temp.func.order]: The presence of unused ellipsis and default
10587 arguments has no effect on the partial ordering of function
10588 templates. add_function_candidate() will not have
10589 counted the "this" argument for constructors. */
10590 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10596 // or, if not that, F1 is more constrained than F2.
10597 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10599 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10604 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10605 if (deduction_guide_p (cand1
->fn
))
10607 gcc_assert (deduction_guide_p (cand2
->fn
));
10608 /* We distinguish between candidates from an explicit deduction guide and
10609 candidates built from a constructor based on DECL_ARTIFICIAL. */
10610 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10611 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10613 return art2
- art1
;
10617 /* Prefer the special copy guide over a declared copy/move
10619 if (copy_guide_p (cand1
->fn
))
10621 if (copy_guide_p (cand2
->fn
))
10624 /* Prefer a candidate generated from a non-template constructor. */
10625 int tg1
= template_guide_p (cand1
->fn
);
10626 int tg2
= template_guide_p (cand2
->fn
);
10632 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10633 for all arguments the corresponding parameters of F1 and F2 have the same
10634 type (CWG 2273/2277). */
10635 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10636 && !DECL_CONV_FN_P (cand1
->fn
)
10637 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10638 && !DECL_CONV_FN_P (cand2
->fn
))
10640 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10641 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10643 bool used1
= false;
10644 bool used2
= false;
10645 if (base1
== base2
)
10646 /* No difference. */;
10647 else if (DERIVED_FROM_P (base1
, base2
))
10649 else if (DERIVED_FROM_P (base2
, base1
))
10652 if (int diff
= used2
- used1
)
10654 for (i
= 0; i
< len
; ++i
)
10656 conversion
*t1
= cand1
->convs
[i
+ off1
];
10657 conversion
*t2
= cand2
->convs
[i
+ off2
];
10658 if (!same_type_p (t1
->type
, t2
->type
))
10666 /* Check whether we can discard a builtin candidate, either because we
10667 have two identical ones or matching builtin and non-builtin candidates.
10669 (Pedantically in the latter case the builtin which matched the user
10670 function should not be added to the overload set, but we spot it here.
10673 ... the builtin candidates include ...
10674 - do not have the same parameter type list as any non-template
10675 non-member candidate. */
10677 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10679 for (i
= 0; i
< len
; ++i
)
10680 if (!same_type_p (cand1
->convs
[i
]->type
,
10681 cand2
->convs
[i
]->type
))
10683 if (i
== cand1
->num_convs
)
10685 if (cand1
->fn
== cand2
->fn
)
10686 /* Two built-in candidates; arbitrarily pick one. */
10688 else if (identifier_p (cand1
->fn
))
10689 /* cand1 is built-in; prefer cand2. */
10692 /* cand2 is built-in; prefer cand1. */
10697 /* For candidates of a multi-versioned function, make the version with
10698 the highest priority win. This version will be checked for dispatching
10699 first. If this version can be inlined into the caller, the front-end
10700 will simply make a direct call to this function. */
10702 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10703 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10704 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10705 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10707 tree f1
= TREE_TYPE (cand1
->fn
);
10708 tree f2
= TREE_TYPE (cand2
->fn
);
10709 tree p1
= TYPE_ARG_TYPES (f1
);
10710 tree p2
= TYPE_ARG_TYPES (f2
);
10712 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10713 is possible that cand1->fn and cand2->fn are function versions but of
10714 different functions. Check types to see if they are versions of the same
10716 if (compparms (p1
, p2
)
10717 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10719 /* Always make the version with the higher priority, more
10720 specialized, win. */
10721 gcc_assert (targetm
.compare_version_priority
);
10722 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10729 /* If the two function declarations represent the same function (this can
10730 happen with declarations in multiple scopes and arg-dependent lookup),
10731 arbitrarily choose one. But first make sure the default args we're
10733 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10734 && equal_functions (cand1
->fn
, cand2
->fn
))
10736 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10737 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10739 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10741 for (i
= 0; i
< len
; ++i
)
10743 /* Don't crash if the fn is variadic. */
10746 parms1
= TREE_CHAIN (parms1
);
10747 parms2
= TREE_CHAIN (parms2
);
10751 parms1
= TREE_CHAIN (parms1
);
10753 parms2
= TREE_CHAIN (parms2
);
10755 for (; parms1
; ++i
)
10757 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10758 TREE_PURPOSE (parms2
)))
10762 if (complain
& tf_error
)
10764 auto_diagnostic_group d
;
10765 if (permerror (input_location
,
10766 "default argument mismatch in "
10767 "overload resolution"))
10769 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10770 " candidate 1: %q#F", cand1
->fn
);
10771 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10772 " candidate 2: %q#F", cand2
->fn
);
10779 add_warning (cand1
, cand2
);
10782 parms1
= TREE_CHAIN (parms1
);
10783 parms2
= TREE_CHAIN (parms2
);
10791 /* Extension: If the worst conversion for one candidate is worse than the
10792 worst conversion for the other, take the first. */
10793 if (!pedantic
&& (complain
& tf_warning_or_error
))
10795 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
10796 struct z_candidate
*w
= 0, *l
= 0;
10798 for (i
= 0; i
< len
; ++i
)
10800 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
10801 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
10802 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
10803 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
10806 winner
= 1, w
= cand1
, l
= cand2
;
10808 winner
= -1, w
= cand2
, l
= cand1
;
10811 /* Don't choose a deleted function over ambiguity. */
10812 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
10816 auto_diagnostic_group d
;
10817 pedwarn (input_location
, 0,
10818 "ISO C++ says that these are ambiguous, even "
10819 "though the worst conversion for the first is better than "
10820 "the worst conversion for the second:");
10821 print_z_candidate (input_location
, _("candidate 1:"), w
);
10822 print_z_candidate (input_location
, _("candidate 2:"), l
);
10825 add_warning (w
, l
);
10830 gcc_assert (!winner
);
10834 /* Given a list of candidates for overloading, find the best one, if any.
10835 This algorithm has a worst case of O(2n) (winner is last), and a best
10836 case of O(n/2) (totally ambiguous); much better than a sorting
10839 static struct z_candidate
*
10840 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
10842 struct z_candidate
*champ
= candidates
, *challenger
;
10844 int champ_compared_to_predecessor
= 0;
10846 /* Walk through the list once, comparing each current champ to the next
10847 candidate, knocking out a candidate or two with each comparison. */
10849 for (challenger
= champ
->next
; challenger
; )
10851 fate
= joust (champ
, challenger
, 0, complain
);
10853 challenger
= challenger
->next
;
10858 champ
= challenger
->next
;
10861 champ_compared_to_predecessor
= 0;
10865 champ
= challenger
;
10866 champ_compared_to_predecessor
= 1;
10869 challenger
= champ
->next
;
10873 /* Make sure the champ is better than all the candidates it hasn't yet
10874 been compared to. */
10876 for (challenger
= candidates
;
10877 challenger
!= champ
10878 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
10879 challenger
= challenger
->next
)
10881 fate
= joust (champ
, challenger
, 0, complain
);
10889 /* Returns nonzero if things of type FROM can be converted to TO. */
10892 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
10894 tree arg
= NULL_TREE
;
10895 /* implicit_conversion only considers user-defined conversions
10896 if it has an expression for the call argument list. */
10897 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
10898 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
10899 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
10902 /* Returns nonzero if things of type FROM can be converted to TO with a
10903 standard conversion. */
10906 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
10908 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
10911 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
10914 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
10915 tsubst_flags_t complain
)
10921 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10922 p
= conversion_obstack_alloc (0);
10923 /* We want to discard any access checks done for this test,
10924 as we might not be in the appropriate access context and
10925 we'll do the check again when we actually perform the
10927 push_deferring_access_checks (dk_deferred
);
10929 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10931 ok_p
= (t
&& !t
->bad_p
);
10933 /* Discard the access checks now. */
10934 pop_deferring_access_checks ();
10935 /* Free all the conversions we allocated. */
10936 obstack_free (&conversion_obstack
, p
);
10941 /* Like can_convert_arg, but allows dubious conversions as well. */
10944 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
10945 tsubst_flags_t complain
)
10950 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10951 p
= conversion_obstack_alloc (0);
10952 /* Try to perform the conversion. */
10953 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10955 /* Free all the conversions we allocated. */
10956 obstack_free (&conversion_obstack
, p
);
10961 /* Convert EXPR to TYPE. Return the converted expression.
10963 Note that we allow bad conversions here because by the time we get to
10964 this point we are committed to doing the conversion. If we end up
10965 doing a bad conversion, convert_like will complain. */
10968 perform_implicit_conversion_flags (tree type
, tree expr
,
10969 tsubst_flags_t complain
, int flags
)
10973 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
10975 if (TYPE_REF_P (type
))
10976 expr
= mark_lvalue_use (expr
);
10978 expr
= mark_rvalue_use (expr
);
10980 if (error_operand_p (expr
))
10981 return error_mark_node
;
10983 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10984 p
= conversion_obstack_alloc (0);
10986 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
10987 /*c_cast_p=*/false,
10992 if (complain
& tf_error
)
10994 /* If expr has unknown type, then it is an overloaded function.
10995 Call instantiate_type to get good error messages. */
10996 if (TREE_TYPE (expr
) == unknown_type_node
)
10997 instantiate_type (type
, expr
, complain
);
10998 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
10999 /* We gave an error. */;
11002 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
11003 gcc_rich_location
rich_loc (loc
, &label
);
11004 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
11005 expr
, TREE_TYPE (expr
), type
);
11008 expr
= error_mark_node
;
11010 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11012 /* In a template, we are only concerned about determining the
11013 type of non-dependent expressions, so we do not have to
11014 perform the actual conversion. But for initializers, we
11015 need to be able to perform it at instantiation
11016 (or instantiate_non_dependent_expr) time. */
11017 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11018 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11019 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11022 expr
= convert_like (conv
, expr
, complain
);
11024 /* Free all the conversions we allocated. */
11025 obstack_free (&conversion_obstack
, p
);
11031 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11033 return perform_implicit_conversion_flags (type
, expr
, complain
,
11037 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11038 permitted. If the conversion is valid, the converted expression is
11039 returned. Otherwise, NULL_TREE is returned, except in the case
11040 that TYPE is a class type; in that case, an error is issued. If
11041 C_CAST_P is true, then this direct-initialization is taking
11042 place as part of a static_cast being attempted as part of a C-style
11046 perform_direct_initialization_if_possible (tree type
,
11049 tsubst_flags_t complain
)
11054 if (type
== error_mark_node
|| error_operand_p (expr
))
11055 return error_mark_node
;
11058 If the destination type is a (possibly cv-qualified) class type:
11060 -- If the initialization is direct-initialization ...,
11061 constructors are considered. ... If no constructor applies, or
11062 the overload resolution is ambiguous, the initialization is
11064 if (CLASS_TYPE_P (type
))
11066 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
11067 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11068 &args
, type
, LOOKUP_NORMAL
, complain
);
11069 release_tree_vector (args
);
11070 return build_cplus_new (type
, expr
, complain
);
11073 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11074 p
= conversion_obstack_alloc (0);
11076 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11078 LOOKUP_NORMAL
, complain
);
11079 if (!conv
|| conv
->bad_p
)
11081 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11083 /* In a template, we are only concerned about determining the
11084 type of non-dependent expressions, so we do not have to
11085 perform the actual conversion. But for initializers, we
11086 need to be able to perform it at instantiation
11087 (or instantiate_non_dependent_expr) time. */
11088 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11089 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11092 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11093 /*issue_conversion_warnings=*/false,
11097 /* Free all the conversions we allocated. */
11098 obstack_free (&conversion_obstack
, p
);
11103 /* When initializing a reference that lasts longer than a full-expression,
11104 this special rule applies:
11108 The temporary to which the reference is bound or the temporary
11109 that is the complete object to which the reference is bound
11110 persists for the lifetime of the reference.
11112 The temporaries created during the evaluation of the expression
11113 initializing the reference, except the temporary to which the
11114 reference is bound, are destroyed at the end of the
11115 full-expression in which they are created.
11117 In that case, we store the converted expression into a new
11118 VAR_DECL in a new scope.
11120 However, we want to be careful not to create temporaries when
11121 they are not required. For example, given:
11124 struct D : public B {};
11128 there is no need to copy the return value from "f"; we can just
11129 extend its lifetime. Similarly, given:
11132 struct T { operator S(); };
11136 we can extend the lifetime of the return value of the conversion
11139 The next several functions are involved in this lifetime extension. */
11141 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11142 reference is being bound to a temporary. Create and return a new
11143 VAR_DECL with the indicated TYPE; this variable will store the value to
11144 which the reference is bound. */
11147 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11149 tree var
= create_temporary_var (type
);
11151 /* Register the variable. */
11153 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11155 /* Namespace-scope or local static; give it a mangled name. */
11156 /* FIXME share comdat with decl? */
11158 TREE_STATIC (var
) = TREE_STATIC (decl
);
11159 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11160 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11162 tree name
= mangle_ref_init_variable (decl
);
11163 DECL_NAME (var
) = name
;
11164 SET_DECL_ASSEMBLER_NAME (var
, name
);
11167 /* Create a new cleanup level if necessary. */
11168 maybe_push_cleanup_level (type
);
11170 return pushdecl (var
);
11173 /* EXPR is the initializer for a variable DECL of reference or
11174 std::initializer_list type. Create, push and return a new VAR_DECL
11175 for the initializer so that it will live as long as DECL. Any
11176 cleanup for the new variable is returned through CLEANUP, and the
11177 code to initialize the new variable is returned through INITP. */
11180 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11187 /* Create the temporary variable. */
11188 type
= TREE_TYPE (expr
);
11189 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11190 layout_decl (var
, 0);
11191 /* If the rvalue is the result of a function call it will be
11192 a TARGET_EXPR. If it is some other construct (such as a
11193 member access expression where the underlying object is
11194 itself the result of a function call), turn it into a
11195 TARGET_EXPR here. It is important that EXPR be a
11196 TARGET_EXPR below since otherwise the INIT_EXPR will
11197 attempt to make a bitwise copy of EXPR to initialize
11199 if (TREE_CODE (expr
) != TARGET_EXPR
)
11200 expr
= get_target_expr (expr
);
11202 if (TREE_CODE (decl
) == FIELD_DECL
11203 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11205 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11206 "until the constructor exits", decl
);
11207 TREE_NO_WARNING (decl
) = true;
11210 /* Recursively extend temps in this initializer. */
11211 TARGET_EXPR_INITIAL (expr
)
11212 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11214 /* Any reference temp has a non-trivial initializer. */
11215 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11217 /* If the initializer is constant, put it in DECL_INITIAL so we get
11218 static initialization and use in constant expressions. */
11219 init
= maybe_constant_init (expr
);
11220 /* As in store_init_value. */
11221 init
= cp_fully_fold (init
);
11222 if (TREE_CONSTANT (init
))
11224 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11226 /* 5.19 says that a constant expression can include an
11227 lvalue-rvalue conversion applied to "a glvalue of literal type
11228 that refers to a non-volatile temporary object initialized
11229 with a constant expression". Rather than try to communicate
11230 that this VAR_DECL is a temporary, just mark it constexpr. */
11231 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11232 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11233 TREE_CONSTANT (var
) = true;
11234 TREE_READONLY (var
) = true;
11236 DECL_INITIAL (var
) = init
;
11240 /* Create the INIT_EXPR that will initialize the temporary
11242 init
= split_nonconstant_init (var
, expr
);
11243 if (at_function_scope_p ())
11245 add_decl_expr (var
);
11247 if (TREE_STATIC (var
))
11248 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11251 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11253 vec_safe_push (*cleanups
, cleanup
);
11256 /* We must be careful to destroy the temporary only
11257 after its initialization has taken place. If the
11258 initialization throws an exception, then the
11259 destructor should not be run. We cannot simply
11260 transform INIT into something like:
11262 (INIT, ({ CLEANUP_STMT; }))
11264 because emit_local_var always treats the
11265 initializer as a full-expression. Thus, the
11266 destructor would run too early; it would run at the
11267 end of initializing the reference variable, rather
11268 than at the end of the block enclosing the
11269 reference variable.
11271 The solution is to pass back a cleanup expression
11272 which the caller is responsible for attaching to
11273 the statement tree. */
11277 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11278 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11280 if (CP_DECL_THREAD_LOCAL_P (var
))
11281 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11284 static_aggregates
= tree_cons (NULL_TREE
, var
,
11285 static_aggregates
);
11288 /* Check whether the dtor is callable. */
11289 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11291 /* Avoid -Wunused-variable warning (c++/38958). */
11292 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11294 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11300 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11301 initializing a variable of that TYPE. */
11304 initialize_reference (tree type
, tree expr
,
11305 int flags
, tsubst_flags_t complain
)
11309 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
11311 if (type
== error_mark_node
|| error_operand_p (expr
))
11312 return error_mark_node
;
11314 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11315 p
= conversion_obstack_alloc (0);
11317 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11319 if (!conv
|| conv
->bad_p
)
11321 if (complain
& tf_error
)
11324 convert_like (conv
, expr
, complain
);
11325 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11326 && !TYPE_REF_IS_RVALUE (type
)
11327 && !lvalue_p (expr
))
11328 error_at (loc
, "invalid initialization of non-const reference of "
11329 "type %qH from an rvalue of type %qI",
11330 type
, TREE_TYPE (expr
));
11332 error_at (loc
, "invalid initialization of reference of type "
11333 "%qH from expression of type %qI", type
,
11336 return error_mark_node
;
11339 if (conv
->kind
== ck_ref_bind
)
11340 /* Perform the conversion. */
11341 expr
= convert_like (conv
, expr
, complain
);
11342 else if (conv
->kind
== ck_ambig
)
11343 /* We gave an error in build_user_type_conversion_1. */
11344 expr
= error_mark_node
;
11346 gcc_unreachable ();
11348 /* Free all the conversions we allocated. */
11349 obstack_free (&conversion_obstack
, p
);
11354 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11355 which is bound either to a reference or a std::initializer_list. */
11358 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11363 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11365 TREE_OPERAND (sub
, 1)
11366 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11369 if (TREE_CODE (sub
) != ADDR_EXPR
)
11371 /* Deal with binding to a subobject. */
11372 for (p
= &TREE_OPERAND (sub
, 0);
11373 (TREE_CODE (*p
) == COMPONENT_REF
11374 || TREE_CODE (*p
) == ARRAY_REF
); )
11375 p
= &TREE_OPERAND (*p
, 0);
11376 if (TREE_CODE (*p
) == TARGET_EXPR
)
11378 tree subinit
= NULL_TREE
;
11379 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11380 recompute_tree_invariant_for_addr_expr (sub
);
11382 init
= fold_convert (TREE_TYPE (init
), sub
);
11384 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11389 /* INIT is part of the initializer for DECL. If there are any
11390 reference or initializer lists being initialized, extend their
11391 lifetime to match that of DECL. */
11394 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11396 tree type
= TREE_TYPE (init
);
11397 if (processing_template_decl
)
11399 if (TYPE_REF_P (type
))
11400 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11404 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11405 ctor
= TARGET_EXPR_INITIAL (ctor
);
11406 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11408 if (is_std_init_list (type
))
11410 /* The temporary array underlying a std::initializer_list
11411 is handled like a reference temporary. */
11412 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11413 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11414 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11419 constructor_elt
*p
;
11420 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11421 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11422 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11424 recompute_constructor_flags (ctor
);
11425 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11426 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11433 /* Returns true iff an initializer for TYPE could contain temporaries that
11434 need to be extended because they are bound to references or
11435 std::initializer_list. */
11438 type_has_extended_temps (tree type
)
11440 type
= strip_array_types (type
);
11441 if (TYPE_REF_P (type
))
11443 if (CLASS_TYPE_P (type
))
11445 if (is_std_init_list (type
))
11447 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11448 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11449 if (type_has_extended_temps (TREE_TYPE (f
)))
11455 /* Returns true iff TYPE is some variant of std::initializer_list. */
11458 is_std_init_list (tree type
)
11460 if (!TYPE_P (type
))
11462 if (cxx_dialect
== cxx98
)
11464 /* Look through typedefs. */
11465 type
= TYPE_MAIN_VARIANT (type
);
11466 return (CLASS_TYPE_P (type
)
11467 && CP_TYPE_CONTEXT (type
) == std_node
11468 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11471 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11472 will accept an argument list of a single std::initializer_list<T>. */
11475 is_list_ctor (tree decl
)
11477 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11480 if (!args
|| args
== void_list_node
)
11483 arg
= non_reference (TREE_VALUE (args
));
11484 if (!is_std_init_list (arg
))
11487 args
= TREE_CHAIN (args
);
11489 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11490 /* There are more non-defaulted parms. */
11496 #include "gt-cp-call.h"