1 /* Functions related to invoking -*- C++ -*- methods and overloaded functions.
2 Copyright (C) 1987-2018 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"
45 /* The various kinds of conversion. */
47 enum conversion_kind
{
64 /* The rank of the conversion. Order of the enumerals matters; better
65 conversions should come earlier in the list. */
67 enum conversion_rank
{
78 /* An implicit conversion sequence, in the sense of [over.best.ics].
79 The first conversion to be performed is at the end of the chain.
80 That conversion is always a cr_identity conversion. */
83 /* The kind of conversion represented by this step. */
85 /* The rank of this conversion. */
87 BOOL_BITFIELD user_conv_p
: 1;
88 BOOL_BITFIELD ellipsis_p
: 1;
89 BOOL_BITFIELD this_p
: 1;
90 /* True if this conversion would be permitted with a bending of
91 language standards, e.g. disregarding pointer qualifiers or
92 converting integers to pointers. */
93 BOOL_BITFIELD bad_p
: 1;
94 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
95 temporary should be created to hold the result of the
96 conversion. If KIND is ck_ambig, true if the context is
97 copy-initialization. */
98 BOOL_BITFIELD need_temporary_p
: 1;
99 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
100 from a pointer-to-derived to pointer-to-base is being performed. */
101 BOOL_BITFIELD base_p
: 1;
102 /* If KIND is ck_ref_bind, true when either an lvalue reference is
103 being bound to an lvalue expression or an rvalue reference is
104 being bound to an rvalue expression. If KIND is ck_rvalue,
105 true when we are treating an lvalue as an rvalue (12.8p33). If
106 KIND is ck_base, always false. If ck_identity, we will be
107 binding a reference directly or decaying to a pointer. */
108 BOOL_BITFIELD rvaluedness_matches_p
: 1;
109 BOOL_BITFIELD check_narrowing
: 1;
110 /* The type of the expression resulting from the conversion. */
113 /* The next conversion in the chain. Since the conversions are
114 arranged from outermost to innermost, the NEXT conversion will
115 actually be performed before this conversion. This variant is
116 used only when KIND is neither ck_identity, ck_ambig nor
117 ck_list. Please use the next_conversion function instead
118 of using this field directly. */
120 /* The expression at the beginning of the conversion chain. This
121 variant is used only if KIND is ck_identity or ck_ambig. */
123 /* The array of conversions for an initializer_list, so this
124 variant is used only when KIN D is ck_list. */
127 /* The function candidate corresponding to this conversion
128 sequence. This field is only used if KIND is ck_user. */
129 struct z_candidate
*cand
;
132 #define CONVERSION_RANK(NODE) \
133 ((NODE)->bad_p ? cr_bad \
134 : (NODE)->ellipsis_p ? cr_ellipsis \
135 : (NODE)->user_conv_p ? cr_user \
138 #define BAD_CONVERSION_RANK(NODE) \
139 ((NODE)->ellipsis_p ? cr_ellipsis \
140 : (NODE)->user_conv_p ? cr_user \
143 static struct obstack conversion_obstack
;
144 static bool conversion_obstack_initialized
;
145 struct rejection_reason
;
147 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
148 static int equal_functions (tree
, tree
);
149 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
151 static int compare_ics (conversion
*, conversion
*);
152 static void maybe_warn_class_memaccess (location_t
, tree
,
153 const vec
<tree
, va_gc
> *);
154 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
155 #define convert_like(CONV, EXPR, COMPLAIN) \
156 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \
157 /*issue_conversion_warnings=*/true, \
158 /*c_cast_p=*/false, (COMPLAIN))
159 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
160 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \
161 /*issue_conversion_warnings=*/true, \
162 /*c_cast_p=*/false, (COMPLAIN))
163 static tree
convert_like_real (conversion
*, tree
, tree
, int, bool,
164 bool, tsubst_flags_t
);
165 static void op_error (location_t
, enum tree_code
, enum tree_code
, tree
,
167 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
169 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
170 static void print_z_candidates (location_t
, struct z_candidate
*);
171 static tree
build_this (tree
);
172 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
173 static bool any_strictly_viable (struct z_candidate
*);
174 static struct z_candidate
*add_template_candidate
175 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
176 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
177 static struct z_candidate
*add_template_candidate_real
178 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
179 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
180 static void add_builtin_candidates
181 (struct z_candidate
**, enum tree_code
, enum tree_code
,
182 tree
, tree
*, int, tsubst_flags_t
);
183 static void add_builtin_candidate
184 (struct z_candidate
**, enum tree_code
, enum tree_code
,
185 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
186 static bool is_complete (tree
);
187 static void build_builtin_candidate
188 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
189 int, tsubst_flags_t
);
190 static struct z_candidate
*add_conv_candidate
191 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
192 tree
, tsubst_flags_t
);
193 static struct z_candidate
*add_function_candidate
194 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
195 tree
, int, tsubst_flags_t
);
196 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
198 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
200 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
201 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
202 static conversion
*next_conversion (conversion
*);
203 static bool is_subseq (conversion
*, conversion
*);
204 static conversion
*maybe_handle_ref_bind (conversion
**);
205 static void maybe_handle_implicit_object (conversion
**);
206 static struct z_candidate
*add_candidate
207 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
208 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
209 static tree
source_type (conversion
*);
210 static void add_warning (struct z_candidate
*, struct z_candidate
*);
211 static bool reference_compatible_p (tree
, tree
);
212 static conversion
*direct_reference_binding (tree
, conversion
*);
213 static bool promoted_arithmetic_type_p (tree
);
214 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
215 static char *name_as_c_string (tree
, tree
, bool *);
216 static tree
prep_operand (tree
);
217 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
218 bool, tree
, tree
, int, struct z_candidate
**,
220 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
221 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
223 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
224 NAME can take many forms... */
227 check_dtor_name (tree basetype
, tree name
)
229 /* Just accept something we've already complained about. */
230 if (name
== error_mark_node
)
233 if (TREE_CODE (name
) == TYPE_DECL
)
234 name
= TREE_TYPE (name
);
235 else if (TYPE_P (name
))
237 else if (identifier_p (name
))
239 if ((MAYBE_CLASS_TYPE_P (basetype
)
240 || TREE_CODE (basetype
) == ENUMERAL_TYPE
)
241 && name
== constructor_name (basetype
))
244 name
= get_type_value (name
);
250 template <class T> struct S { ~S(); };
254 NAME will be a class template. */
255 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
259 if (!name
|| name
== error_mark_node
)
261 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
264 /* We want the address of a function or method. We avoid creating a
265 pointer-to-member function. */
268 build_addr_func (tree function
, tsubst_flags_t complain
)
270 tree type
= TREE_TYPE (function
);
272 /* We have to do these by hand to avoid real pointer to member
274 if (TREE_CODE (type
) == METHOD_TYPE
)
276 if (TREE_CODE (function
) == OFFSET_REF
)
278 tree object
= build_address (TREE_OPERAND (function
, 0));
279 return get_member_function_from_ptrfunc (&object
,
280 TREE_OPERAND (function
, 1),
283 function
= build_address (function
);
286 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
291 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
292 POINTER_TYPE to those. Note, pointer to member function types
293 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
294 two variants. build_call_a is the primitive taking an array of
295 arguments, while build_call_n is a wrapper that handles varargs. */
298 build_call_n (tree function
, int n
, ...)
301 return build_call_a (function
, 0, NULL
);
304 tree
*argarray
= XALLOCAVEC (tree
, n
);
309 for (i
= 0; i
< n
; i
++)
310 argarray
[i
] = va_arg (ap
, tree
);
312 return build_call_a (function
, n
, argarray
);
316 /* Update various flags in cfun and the call itself based on what is being
317 called. Split out of build_call_a so that bot_manip can use it too. */
320 set_flags_from_callee (tree call
)
323 tree decl
= get_callee_fndecl (call
);
325 /* We check both the decl and the type; a function may be known not to
326 throw without being declared throw(). */
327 nothrow
= decl
&& TREE_NOTHROW (decl
);
328 if (CALL_EXPR_FN (call
))
329 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call
))));
330 else if (internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
333 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
334 cp_function_chain
->can_throw
= 1;
336 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
337 current_function_returns_abnormally
= 1;
339 TREE_NOTHROW (call
) = nothrow
;
343 build_call_a (tree function
, int n
, tree
*argarray
)
350 function
= build_addr_func (function
, tf_warning_or_error
);
352 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
353 fntype
= TREE_TYPE (TREE_TYPE (function
));
354 gcc_assert (TREE_CODE (fntype
) == FUNCTION_TYPE
355 || TREE_CODE (fntype
) == METHOD_TYPE
);
356 result_type
= TREE_TYPE (fntype
);
357 /* An rvalue has no cv-qualifiers. */
358 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
359 result_type
= cv_unqualified (result_type
);
361 function
= build_call_array_loc (input_location
,
362 result_type
, function
, n
, argarray
);
363 set_flags_from_callee (function
);
365 decl
= get_callee_fndecl (function
);
367 if (decl
&& !TREE_USED (decl
))
369 /* We invoke build_call directly for several library
370 functions. These may have been declared normally if
371 we're building libgcc, so we can't just check
373 gcc_assert (DECL_ARTIFICIAL (decl
)
374 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
379 require_complete_eh_spec_types (fntype
, decl
);
381 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
383 /* Don't pass empty class objects by value. This is useful
384 for tags in STL, which are used to control overload resolution.
385 We don't need to handle other cases of copying empty classes. */
386 if (! decl
|| ! DECL_BUILT_IN (decl
))
387 for (i
= 0; i
< n
; i
++)
389 tree arg
= CALL_EXPR_ARG (function
, i
);
390 if (is_empty_class (TREE_TYPE (arg
))
391 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
393 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
394 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
395 CALL_EXPR_ARG (function
, i
) = arg
;
402 /* New overloading code. */
406 struct candidate_warning
{
408 candidate_warning
*next
;
411 /* Information for providing diagnostics about why overloading failed. */
413 enum rejection_reason_code
{
416 rr_explicit_conversion
,
417 rr_template_conversion
,
419 rr_bad_arg_conversion
,
420 rr_template_unification
,
423 rr_constraint_failure
426 struct conversion_info
{
427 /* The index of the argument, 0-based. */
429 /* The actual argument or its type. */
431 /* The type of the parameter. */
435 struct rejection_reason
{
436 enum rejection_reason_code code
;
438 /* Information about an arity mismatch. */
440 /* The expected number of arguments. */
442 /* The actual number of arguments in the call. */
444 /* Whether the call was a varargs call. */
447 /* Information about an argument conversion mismatch. */
448 struct conversion_info conversion
;
449 /* Same, but for bad argument conversions. */
450 struct conversion_info bad_conversion
;
451 /* Information about template unification failures. These are the
452 parameters passed to fn_type_unification. */
460 unification_kind_t strict
;
462 } template_unification
;
463 /* Information about template instantiation failures. These are the
464 parameters passed to instantiate_template. */
468 } template_instantiation
;
473 /* The FUNCTION_DECL that will be called if this candidate is
474 selected by overload resolution. */
476 /* If not NULL_TREE, the first argument to use when calling this
479 /* The rest of the arguments to use when calling this function. If
480 there are no further arguments this may be NULL or it may be an
482 const vec
<tree
, va_gc
> *args
;
483 /* The implicit conversion sequences for each of the arguments to
486 /* The number of implicit conversion sequences. */
488 /* If FN is a user-defined conversion, the standard conversion
489 sequence from the type returned by FN to the desired destination
491 conversion
*second_conv
;
492 struct rejection_reason
*reason
;
493 /* If FN is a member function, the binfo indicating the path used to
494 qualify the name of FN at the call site. This path is used to
495 determine whether or not FN is accessible if it is selected by
496 overload resolution. The DECL_CONTEXT of FN will always be a
497 (possibly improper) base of this binfo. */
499 /* If FN is a non-static member function, the binfo indicating the
500 subobject to which the `this' pointer should be converted if FN
501 is selected by overload resolution. The type pointed to by
502 the `this' pointer must correspond to the most derived class
503 indicated by the CONVERSION_PATH. */
504 tree conversion_path
;
507 candidate_warning
*warnings
;
511 /* The flags active in add_candidate. */
515 /* Returns true iff T is a null pointer constant in the sense of
519 null_ptr_cst_p (tree t
)
521 tree type
= TREE_TYPE (t
);
525 A null pointer constant is an integral constant expression
526 (_expr.const_) rvalue of integer type that evaluates to zero or
527 an rvalue of type std::nullptr_t. */
528 if (NULLPTR_TYPE_P (type
))
531 if (cxx_dialect
>= cxx11
)
533 STRIP_ANY_LOCATION_WRAPPER (t
);
535 /* Core issue 903 says only literal 0 is a null pointer constant. */
536 if (TREE_CODE (type
) == INTEGER_TYPE
537 && !char_type_p (type
)
538 && TREE_CODE (t
) == INTEGER_CST
540 && !TREE_OVERFLOW (t
))
543 else if (CP_INTEGRAL_TYPE_P (type
))
545 t
= fold_non_dependent_expr (t
);
547 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
554 /* Returns true iff T is a null member pointer value (4.11). */
557 null_member_pointer_value_p (tree t
)
559 tree type
= TREE_TYPE (t
);
562 else if (TYPE_PTRMEMFUNC_P (type
))
563 return (TREE_CODE (t
) == CONSTRUCTOR
564 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
565 else if (TYPE_PTRDATAMEM_P (type
))
566 return integer_all_onesp (t
);
571 /* Returns nonzero if PARMLIST consists of only default parms,
572 ellipsis, and/or undeduced parameter packs. */
575 sufficient_parms_p (const_tree parmlist
)
577 for (; parmlist
&& parmlist
!= void_list_node
;
578 parmlist
= TREE_CHAIN (parmlist
))
579 if (!TREE_PURPOSE (parmlist
)
580 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
585 /* Allocate N bytes of memory from the conversion obstack. The memory
586 is zeroed before being returned. */
589 conversion_obstack_alloc (size_t n
)
592 if (!conversion_obstack_initialized
)
594 gcc_obstack_init (&conversion_obstack
);
595 conversion_obstack_initialized
= true;
597 p
= obstack_alloc (&conversion_obstack
, n
);
602 /* Allocate rejection reasons. */
604 static struct rejection_reason
*
605 alloc_rejection (enum rejection_reason_code code
)
607 struct rejection_reason
*p
;
608 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
613 static struct rejection_reason
*
614 arity_rejection (tree first_arg
, int expected
, int actual
)
616 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
617 int adjust
= first_arg
!= NULL_TREE
;
618 r
->u
.arity
.expected
= expected
- adjust
;
619 r
->u
.arity
.actual
= actual
- adjust
;
623 static struct rejection_reason
*
624 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
)
626 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
627 int adjust
= first_arg
!= NULL_TREE
;
628 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
629 r
->u
.conversion
.from
= from
;
630 r
->u
.conversion
.to_type
= to
;
634 static struct rejection_reason
*
635 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
)
637 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
638 int adjust
= first_arg
!= NULL_TREE
;
639 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
640 r
->u
.bad_conversion
.from
= from
;
641 r
->u
.bad_conversion
.to_type
= to
;
645 static struct rejection_reason
*
646 explicit_conversion_rejection (tree from
, tree to
)
648 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
649 r
->u
.conversion
.n_arg
= 0;
650 r
->u
.conversion
.from
= from
;
651 r
->u
.conversion
.to_type
= to
;
655 static struct rejection_reason
*
656 template_conversion_rejection (tree from
, tree to
)
658 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
659 r
->u
.conversion
.n_arg
= 0;
660 r
->u
.conversion
.from
= from
;
661 r
->u
.conversion
.to_type
= to
;
665 static struct rejection_reason
*
666 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
667 const tree
*args
, unsigned int nargs
,
668 tree return_type
, unification_kind_t strict
,
671 size_t args_n_bytes
= sizeof (*args
) * nargs
;
672 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
673 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
674 r
->u
.template_unification
.tmpl
= tmpl
;
675 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
676 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
677 /* Copy args to our own storage. */
678 memcpy (args1
, args
, args_n_bytes
);
679 r
->u
.template_unification
.args
= args1
;
680 r
->u
.template_unification
.nargs
= nargs
;
681 r
->u
.template_unification
.return_type
= return_type
;
682 r
->u
.template_unification
.strict
= strict
;
683 r
->u
.template_unification
.flags
= flags
;
687 static struct rejection_reason
*
688 template_unification_error_rejection (void)
690 return alloc_rejection (rr_template_unification
);
693 static struct rejection_reason
*
694 invalid_copy_with_fn_template_rejection (void)
696 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
700 static struct rejection_reason
*
701 inherited_ctor_rejection (void)
703 struct rejection_reason
*r
= alloc_rejection (rr_inherited_ctor
);
707 // Build a constraint failure record, saving information into the
708 // template_instantiation field of the rejection. If FN is not a template
709 // declaration, the TMPL member is the FN declaration and TARGS is empty.
711 static struct rejection_reason
*
712 constraint_failure (tree fn
)
714 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
715 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
717 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
718 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
722 r
->u
.template_instantiation
.tmpl
= fn
;
723 r
->u
.template_instantiation
.targs
= NULL_TREE
;
728 /* Dynamically allocate a conversion. */
731 alloc_conversion (conversion_kind kind
)
734 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
739 /* Make sure that all memory on the conversion obstack has been
743 validate_conversion_obstack (void)
745 if (conversion_obstack_initialized
)
746 gcc_assert ((obstack_next_free (&conversion_obstack
)
747 == obstack_base (&conversion_obstack
)));
750 /* Dynamically allocate an array of N conversions. */
753 alloc_conversions (size_t n
)
755 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
759 build_conv (conversion_kind code
, tree type
, conversion
*from
)
762 conversion_rank rank
= CONVERSION_RANK (from
);
764 /* Note that the caller is responsible for filling in t->cand for
765 user-defined conversions. */
766 t
= alloc_conversion (code
);
790 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
791 t
->bad_p
= from
->bad_p
;
796 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
797 specialization of std::initializer_list<T>, if such a conversion is
801 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
803 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
804 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
805 conversion
**subconvs
= alloc_conversions (len
);
810 /* Within a list-initialization we can have more user-defined
812 flags
&= ~LOOKUP_NO_CONVERSION
;
813 /* But no narrowing conversions. */
814 flags
|= LOOKUP_NO_NARROWING
;
816 /* Can't make an array of these types. */
817 if (TREE_CODE (elttype
) == REFERENCE_TYPE
818 || TREE_CODE (elttype
) == FUNCTION_TYPE
819 || VOID_TYPE_P (elttype
))
822 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
825 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
826 false, flags
, complain
);
833 t
= alloc_conversion (ck_list
);
835 t
->u
.list
= subconvs
;
838 for (i
= 0; i
< len
; ++i
)
840 conversion
*sub
= subconvs
[i
];
841 if (sub
->rank
> t
->rank
)
843 if (sub
->user_conv_p
)
844 t
->user_conv_p
= true;
852 /* Return the next conversion of the conversion chain (if applicable),
853 or NULL otherwise. Please use this function instead of directly
854 accessing fields of struct conversion. */
857 next_conversion (conversion
*conv
)
860 || conv
->kind
== ck_identity
861 || conv
->kind
== ck_ambig
862 || conv
->kind
== ck_list
)
867 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
868 is a valid aggregate initializer for array type ATYPE. */
871 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
874 tree elttype
= TREE_TYPE (atype
);
875 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
877 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
879 if (TREE_CODE (elttype
) == ARRAY_TYPE
880 && TREE_CODE (val
) == CONSTRUCTOR
)
881 ok
= can_convert_array (elttype
, val
, flags
, complain
);
883 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
891 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
892 aggregate class, if such a conversion is possible. */
895 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
897 unsigned HOST_WIDE_INT i
= 0;
899 tree field
= next_initializable_field (TYPE_FIELDS (type
));
900 tree empty_ctor
= NULL_TREE
;
902 /* We already called reshape_init in implicit_conversion. */
904 /* The conversions within the init-list aren't affected by the enclosing
905 context; they're always simple copy-initialization. */
906 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
908 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
910 tree ftype
= TREE_TYPE (field
);
914 if (i
< CONSTRUCTOR_NELTS (ctor
))
915 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
916 else if (DECL_INITIAL (field
))
917 val
= get_nsdmi (field
, /*ctor*/false, complain
);
918 else if (TREE_CODE (ftype
) == REFERENCE_TYPE
)
919 /* Value-initialization of reference is ill-formed. */
923 if (empty_ctor
== NULL_TREE
)
924 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
929 if (TREE_CODE (ftype
) == ARRAY_TYPE
930 && TREE_CODE (val
) == CONSTRUCTOR
)
931 ok
= can_convert_array (ftype
, val
, flags
, complain
);
933 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
939 if (TREE_CODE (type
) == UNION_TYPE
)
943 if (i
< CONSTRUCTOR_NELTS (ctor
))
946 c
= alloc_conversion (ck_aggr
);
949 c
->user_conv_p
= true;
950 c
->check_narrowing
= true;
955 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
956 array type, if such a conversion is possible. */
959 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
962 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
963 tree elttype
= TREE_TYPE (type
);
968 enum conversion_rank rank
= cr_exact
;
970 /* We might need to propagate the size from the element to the array. */
971 complete_type (type
);
973 if (TYPE_DOMAIN (type
)
974 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
976 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
981 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
983 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
986 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
987 false, flags
, complain
);
991 if (sub
->rank
> rank
)
993 if (sub
->user_conv_p
)
999 c
= alloc_conversion (ck_aggr
);
1002 c
->user_conv_p
= user
;
1008 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1009 complex type, if such a conversion is possible. */
1012 build_complex_conv (tree type
, tree ctor
, int flags
,
1013 tsubst_flags_t complain
)
1016 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1017 tree elttype
= TREE_TYPE (type
);
1022 enum conversion_rank rank
= cr_exact
;
1027 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1029 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1032 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1033 false, flags
, complain
);
1037 if (sub
->rank
> rank
)
1039 if (sub
->user_conv_p
)
1045 c
= alloc_conversion (ck_aggr
);
1048 c
->user_conv_p
= user
;
1054 /* Build a representation of the identity conversion from EXPR to
1055 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1058 build_identity_conv (tree type
, tree expr
)
1062 c
= alloc_conversion (ck_identity
);
1069 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1070 were multiple user-defined conversions to accomplish the job.
1071 Build a conversion that indicates that ambiguity. */
1074 build_ambiguous_conv (tree type
, tree expr
)
1078 c
= alloc_conversion (ck_ambig
);
1086 strip_top_quals (tree t
)
1088 if (TREE_CODE (t
) == ARRAY_TYPE
)
1090 return cp_build_qualified_type (t
, 0);
1093 /* Returns the standard conversion path (see [conv]) from type FROM to type
1094 TO, if any. For proper handling of null pointer constants, you must
1095 also pass the expression EXPR to convert from. If C_CAST_P is true,
1096 this conversion is coming from a C-style cast. */
1099 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1100 int flags
, tsubst_flags_t complain
)
1102 enum tree_code fcode
, tcode
;
1104 bool fromref
= false;
1107 to
= non_reference (to
);
1108 if (TREE_CODE (from
) == REFERENCE_TYPE
)
1111 from
= TREE_TYPE (from
);
1114 to
= strip_top_quals (to
);
1115 from
= strip_top_quals (from
);
1117 if (expr
&& type_unknown_p (expr
))
1119 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1121 tsubst_flags_t tflags
= tf_conv
;
1122 expr
= instantiate_type (to
, expr
, tflags
);
1123 if (expr
== error_mark_node
)
1125 from
= TREE_TYPE (expr
);
1127 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1129 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1130 expr
= resolve_nondeduced_context (expr
, complain
);
1131 from
= TREE_TYPE (expr
);
1135 fcode
= TREE_CODE (from
);
1136 tcode
= TREE_CODE (to
);
1138 conv
= build_identity_conv (from
, expr
);
1139 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1141 from
= type_decays_to (from
);
1142 fcode
= TREE_CODE (from
);
1143 /* Tell convert_like_real that we're using the address. */
1144 conv
->rvaluedness_matches_p
= true;
1145 conv
= build_conv (ck_lvalue
, from
, conv
);
1147 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1148 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1149 express the copy constructor call required by copy-initialization. */
1150 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1155 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1158 from
= strip_top_quals (bitfield_type
);
1159 fcode
= TREE_CODE (from
);
1162 conv
= build_conv (ck_rvalue
, from
, conv
);
1163 if (flags
& LOOKUP_PREFER_RVALUE
)
1164 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1165 conv
->rvaluedness_matches_p
= true;
1168 /* Allow conversion between `__complex__' data types. */
1169 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1171 /* The standard conversion sequence to convert FROM to TO is
1172 the standard conversion sequence to perform componentwise
1174 conversion
*part_conv
= standard_conversion
1175 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1180 conv
= build_conv (part_conv
->kind
, to
, conv
);
1181 conv
->rank
= part_conv
->rank
;
1189 if (same_type_p (from
, to
))
1191 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1192 conv
->type
= qualified_to
;
1197 A null pointer constant can be converted to a pointer type; ... A
1198 null pointer constant of integral type can be converted to an
1199 rvalue of type std::nullptr_t. */
1200 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1201 || NULLPTR_TYPE_P (to
))
1202 && ((expr
&& null_ptr_cst_p (expr
))
1203 || NULLPTR_TYPE_P (from
)))
1204 conv
= build_conv (ck_std
, to
, conv
);
1205 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1206 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1208 /* For backwards brain damage compatibility, allow interconversion of
1209 pointers and integers with a pedwarn. */
1210 conv
= build_conv (ck_std
, to
, conv
);
1213 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1215 /* For backwards brain damage compatibility, allow interconversion of
1216 enums and integers with a pedwarn. */
1217 conv
= build_conv (ck_std
, to
, conv
);
1220 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1221 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1226 if (tcode
== POINTER_TYPE
)
1228 to_pointee
= TREE_TYPE (to
);
1229 from_pointee
= TREE_TYPE (from
);
1231 /* Since this is the target of a pointer, it can't have function
1232 qualifiers, so any TYPE_QUALS must be for attributes const or
1233 noreturn. Strip them. */
1234 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1235 && TYPE_QUALS (to_pointee
))
1236 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1237 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1238 && TYPE_QUALS (from_pointee
))
1239 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1243 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1244 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1247 if (tcode
== POINTER_TYPE
1248 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1251 else if (VOID_TYPE_P (to_pointee
)
1252 && !TYPE_PTRDATAMEM_P (from
)
1253 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1255 tree nfrom
= TREE_TYPE (from
);
1256 /* Don't try to apply restrict to void. */
1257 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1258 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1259 from
= build_pointer_type (from_pointee
);
1260 conv
= build_conv (ck_ptr
, from
, conv
);
1262 else if (TYPE_PTRDATAMEM_P (from
))
1264 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1265 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1267 if (same_type_p (fbase
, tbase
))
1268 /* No base conversion needed. */;
1269 else if (DERIVED_FROM_P (fbase
, tbase
)
1270 && (same_type_ignoring_top_level_qualifiers_p
1271 (from_pointee
, to_pointee
)))
1273 from
= build_ptrmem_type (tbase
, from_pointee
);
1274 conv
= build_conv (ck_pmem
, from
, conv
);
1279 else if (CLASS_TYPE_P (from_pointee
)
1280 && CLASS_TYPE_P (to_pointee
)
1283 An rvalue of type "pointer to cv D," where D is a
1284 class type, can be converted to an rvalue of type
1285 "pointer to cv B," where B is a base class (clause
1286 _class.derived_) of D. If B is an inaccessible
1287 (clause _class.access_) or ambiguous
1288 (_class.member.lookup_) base class of D, a program
1289 that necessitates this conversion is ill-formed.
1290 Therefore, we use DERIVED_FROM_P, and do not check
1291 access or uniqueness. */
1292 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1295 = cp_build_qualified_type (to_pointee
,
1296 cp_type_quals (from_pointee
));
1297 from
= build_pointer_type (from_pointee
);
1298 conv
= build_conv (ck_ptr
, from
, conv
);
1299 conv
->base_p
= true;
1302 if (same_type_p (from
, to
))
1304 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1305 /* In a C-style cast, we ignore CV-qualification because we
1306 are allowed to perform a static_cast followed by a
1308 conv
= build_conv (ck_qual
, to
, conv
);
1309 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1310 conv
= build_conv (ck_qual
, to
, conv
);
1311 else if (expr
&& string_conv_p (to
, expr
, 0))
1312 /* converting from string constant to char *. */
1313 conv
= build_conv (ck_qual
, to
, conv
);
1314 else if (fnptr_conv_p (to
, from
))
1315 conv
= build_conv (ck_fnptr
, to
, conv
);
1316 /* Allow conversions among compatible ObjC pointer types (base
1317 conversions have been already handled above). */
1318 else if (c_dialect_objc ()
1319 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1320 conv
= build_conv (ck_ptr
, to
, conv
);
1321 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1323 conv
= build_conv (ck_ptr
, to
, conv
);
1331 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1333 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1334 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1335 tree fbase
= class_of_this_parm (fromfn
);
1336 tree tbase
= class_of_this_parm (tofn
);
1338 if (!DERIVED_FROM_P (fbase
, tbase
))
1341 tree fstat
= static_fn_type (fromfn
);
1342 tree tstat
= static_fn_type (tofn
);
1343 if (same_type_p (tstat
, fstat
)
1344 || fnptr_conv_p (tstat
, fstat
))
1349 if (!same_type_p (fbase
, tbase
))
1351 from
= build_memfn_type (fstat
,
1353 cp_type_quals (tbase
),
1354 type_memfn_rqual (tofn
));
1355 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1356 conv
= build_conv (ck_pmem
, from
, conv
);
1357 conv
->base_p
= true;
1359 if (fnptr_conv_p (tstat
, fstat
))
1360 conv
= build_conv (ck_fnptr
, to
, conv
);
1362 else if (tcode
== BOOLEAN_TYPE
)
1366 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1367 to member type can be converted to a prvalue of type bool. ...
1368 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1369 std::nullptr_t can be converted to a prvalue of type bool; */
1370 if (ARITHMETIC_TYPE_P (from
)
1371 || UNSCOPED_ENUM_P (from
)
1372 || fcode
== POINTER_TYPE
1373 || TYPE_PTRMEM_P (from
)
1374 || NULLPTR_TYPE_P (from
))
1376 conv
= build_conv (ck_std
, to
, conv
);
1377 if (fcode
== POINTER_TYPE
1378 || TYPE_PTRDATAMEM_P (from
)
1379 || (TYPE_PTRMEMFUNC_P (from
)
1380 && conv
->rank
< cr_pbool
)
1381 || NULLPTR_TYPE_P (from
))
1382 conv
->rank
= cr_pbool
;
1383 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1390 /* We don't check for ENUMERAL_TYPE here because there are no standard
1391 conversions to enum type. */
1392 /* As an extension, allow conversion to complex type. */
1393 else if (ARITHMETIC_TYPE_P (to
))
1395 if (! (INTEGRAL_CODE_P (fcode
)
1396 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1397 || SCOPED_ENUM_P (from
))
1399 conv
= build_conv (ck_std
, to
, conv
);
1401 /* Give this a better rank if it's a promotion. */
1402 if (same_type_p (to
, type_promotes_to (from
))
1403 && next_conversion (conv
)->rank
<= cr_promotion
)
1404 conv
->rank
= cr_promotion
;
1406 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1407 && vector_types_convertible_p (from
, to
, false))
1408 return build_conv (ck_std
, to
, conv
);
1409 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1410 && is_properly_derived_from (from
, to
))
1412 if (conv
->kind
== ck_rvalue
)
1413 conv
= next_conversion (conv
);
1414 conv
= build_conv (ck_base
, to
, conv
);
1415 /* The derived-to-base conversion indicates the initialization
1416 of a parameter with base type from an object of a derived
1417 type. A temporary object is created to hold the result of
1418 the conversion unless we're binding directly to a reference. */
1419 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1424 if (flags
& LOOKUP_NO_NARROWING
)
1425 conv
->check_narrowing
= true;
1430 /* Returns nonzero if T1 is reference-related to T2. */
1433 reference_related_p (tree t1
, tree t2
)
1435 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1438 t1
= TYPE_MAIN_VARIANT (t1
);
1439 t2
= TYPE_MAIN_VARIANT (t2
);
1443 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1444 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1446 return (same_type_p (t1
, t2
)
1447 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1448 && DERIVED_FROM_P (t1
, t2
)));
1451 /* Returns nonzero if T1 is reference-compatible with T2. */
1454 reference_compatible_p (tree t1
, tree t2
)
1458 "cv1 T1" is reference compatible with "cv2 T2" if
1459 * T1 is reference-related to T2 or
1460 * T2 is "noexcept function" and T1 is "function", where the
1461 function types are otherwise the same,
1462 and cv1 is the same cv-qualification as, or greater cv-qualification
1464 return ((reference_related_p (t1
, t2
)
1465 || fnptr_conv_p (t1
, t2
))
1466 && at_least_as_qualified_p (t1
, t2
));
1469 /* A reference of the indicated TYPE is being bound directly to the
1470 expression represented by the implicit conversion sequence CONV.
1471 Return a conversion sequence for this binding. */
1474 direct_reference_binding (tree type
, conversion
*conv
)
1478 gcc_assert (TREE_CODE (type
) == REFERENCE_TYPE
);
1479 gcc_assert (TREE_CODE (conv
->type
) != REFERENCE_TYPE
);
1481 t
= TREE_TYPE (type
);
1483 if (conv
->kind
== ck_identity
)
1484 /* Mark the identity conv as to not decay to rvalue. */
1485 conv
->rvaluedness_matches_p
= true;
1489 When a parameter of reference type binds directly
1490 (_dcl.init.ref_) to an argument expression, the implicit
1491 conversion sequence is the identity conversion, unless the
1492 argument expression has a type that is a derived class of the
1493 parameter type, in which case the implicit conversion sequence is
1494 a derived-to-base Conversion.
1496 If the parameter binds directly to the result of applying a
1497 conversion function to the argument expression, the implicit
1498 conversion sequence is a user-defined conversion sequence
1499 (_over.ics.user_), with the second standard conversion sequence
1500 either an identity conversion or, if the conversion function
1501 returns an entity of a type that is a derived class of the
1502 parameter type, a derived-to-base conversion. */
1503 if (is_properly_derived_from (conv
->type
, t
))
1505 /* Represent the derived-to-base conversion. */
1506 conv
= build_conv (ck_base
, t
, conv
);
1507 /* We will actually be binding to the base-class subobject in
1508 the derived class, so we mark this conversion appropriately.
1509 That way, convert_like knows not to generate a temporary. */
1510 conv
->need_temporary_p
= false;
1513 return build_conv (ck_ref_bind
, type
, conv
);
1516 /* Returns the conversion path from type FROM to reference type TO for
1517 purposes of reference binding. For lvalue binding, either pass a
1518 reference type to FROM or an lvalue expression to EXPR. If the
1519 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1520 the conversion returned. If C_CAST_P is true, this
1521 conversion is coming from a C-style cast. */
1524 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1525 tsubst_flags_t complain
)
1527 conversion
*conv
= NULL
;
1528 tree to
= TREE_TYPE (rto
);
1533 cp_lvalue_kind gl_kind
;
1536 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1538 expr
= instantiate_type (to
, expr
, tf_none
);
1539 if (expr
== error_mark_node
)
1541 from
= TREE_TYPE (expr
);
1544 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1546 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1547 /* DR 1288: Otherwise, if the initializer list has a single element
1548 of type E and ... [T's] referenced type is reference-related to E,
1549 the object or reference is initialized from that element... */
1550 if (CONSTRUCTOR_NELTS (expr
) == 1)
1552 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1553 if (error_operand_p (elt
))
1555 tree etype
= TREE_TYPE (elt
);
1556 if (reference_related_p (to
, etype
))
1563 /* Otherwise, if T is a reference type, a prvalue temporary of the
1564 type referenced by T is copy-list-initialized or
1565 direct-list-initialized, depending on the kind of initialization
1566 for the reference, and the reference is bound to that temporary. */
1567 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1568 flags
|LOOKUP_NO_TEMP_BIND
, complain
);
1572 if (TREE_CODE (from
) == REFERENCE_TYPE
)
1574 from
= TREE_TYPE (from
);
1575 if (!TYPE_REF_IS_RVALUE (rfrom
)
1576 || TREE_CODE (from
) == FUNCTION_TYPE
)
1577 gl_kind
= clk_ordinary
;
1579 gl_kind
= clk_rvalueref
;
1582 gl_kind
= lvalue_kind (expr
);
1583 else if (CLASS_TYPE_P (from
)
1584 || TREE_CODE (from
) == ARRAY_TYPE
)
1585 gl_kind
= clk_class
;
1589 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1590 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1591 && (gl_kind
& clk_class
))
1594 /* Same mask as real_lvalue_p. */
1595 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1598 if ((gl_kind
& clk_bitfield
) != 0)
1599 tfrom
= unlowered_expr_type (expr
);
1601 /* Figure out whether or not the types are reference-related and
1602 reference compatible. We have to do this after stripping
1603 references from FROM. */
1604 related_p
= reference_related_p (to
, tfrom
);
1605 /* If this is a C cast, first convert to an appropriately qualified
1606 type, so that we can later do a const_cast to the desired type. */
1607 if (related_p
&& c_cast_p
1608 && !at_least_as_qualified_p (to
, tfrom
))
1609 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1610 compatible_p
= reference_compatible_p (to
, tfrom
);
1612 /* Directly bind reference when target expression's type is compatible with
1613 the reference and expression is an lvalue. In DR391, the wording in
1614 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1615 const and rvalue references to rvalues of compatible class type.
1616 We should also do direct bindings for non-class xvalues. */
1617 if ((related_p
|| compatible_p
) && gl_kind
)
1621 If the initializer expression
1623 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1624 is reference-compatible with "cv2 T2,"
1626 the reference is bound directly to the initializer expression
1630 If the initializer expression is an rvalue, with T2 a class type,
1631 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1632 is bound to the object represented by the rvalue or to a sub-object
1633 within that object. */
1635 conv
= build_identity_conv (tfrom
, expr
);
1636 conv
= direct_reference_binding (rto
, conv
);
1638 if (TREE_CODE (rfrom
) == REFERENCE_TYPE
)
1639 /* Handle rvalue reference to function properly. */
1640 conv
->rvaluedness_matches_p
1641 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1643 conv
->rvaluedness_matches_p
1644 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1646 if ((gl_kind
& clk_bitfield
) != 0
1647 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1648 /* For the purposes of overload resolution, we ignore the fact
1649 this expression is a bitfield or packed field. (In particular,
1650 [over.ics.ref] says specifically that a function with a
1651 non-const reference parameter is viable even if the
1652 argument is a bitfield.)
1654 However, when we actually call the function we must create
1655 a temporary to which to bind the reference. If the
1656 reference is volatile, or isn't const, then we cannot make
1657 a temporary, so we just issue an error when the conversion
1659 conv
->need_temporary_p
= true;
1661 /* Don't allow binding of lvalues (other than function lvalues) to
1662 rvalue references. */
1663 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1664 && TREE_CODE (to
) != FUNCTION_TYPE
)
1667 /* Nor the reverse. */
1668 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1669 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1670 || (flags
& LOOKUP_NO_RVAL_BIND
))
1671 && TREE_CODE (to
) != FUNCTION_TYPE
)
1679 /* [class.conv.fct] A conversion function is never used to convert a
1680 (possibly cv-qualified) object to the (possibly cv-qualified) same
1681 object type (or a reference to it), to a (possibly cv-qualified) base
1682 class of that type (or a reference to it).... */
1683 else if (CLASS_TYPE_P (from
) && !related_p
1684 && !(flags
& LOOKUP_NO_CONVERSION
))
1688 If the initializer expression
1690 -- has a class type (i.e., T2 is a class type) can be
1691 implicitly converted to an lvalue of type "cv3 T3," where
1692 "cv1 T1" is reference-compatible with "cv3 T3". (this
1693 conversion is selected by enumerating the applicable
1694 conversion functions (_over.match.ref_) and choosing the
1695 best one through overload resolution. (_over.match_).
1697 the reference is bound to the lvalue result of the conversion
1698 in the second case. */
1699 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1702 return cand
->second_conv
;
1705 /* From this point on, we conceptually need temporaries, even if we
1706 elide them. Only the cases above are "direct bindings". */
1707 if (flags
& LOOKUP_NO_TEMP_BIND
)
1712 When a parameter of reference type is not bound directly to an
1713 argument expression, the conversion sequence is the one required
1714 to convert the argument expression to the underlying type of the
1715 reference according to _over.best.ics_. Conceptually, this
1716 conversion sequence corresponds to copy-initializing a temporary
1717 of the underlying type with the argument expression. Any
1718 difference in top-level cv-qualification is subsumed by the
1719 initialization itself and does not constitute a conversion. */
1723 Otherwise, the reference shall be an lvalue reference to a
1724 non-volatile const type, or the reference shall be an rvalue
1727 We try below to treat this as a bad conversion to improve diagnostics,
1728 but if TO is an incomplete class, we need to reject this conversion
1729 now to avoid unnecessary instantiation. */
1730 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1731 && !COMPLETE_TYPE_P (to
))
1734 /* We're generating a temporary now, but don't bind any more in the
1735 conversion (specifically, don't slice the temporary returned by a
1736 conversion operator). */
1737 flags
|= LOOKUP_NO_TEMP_BIND
;
1739 /* Core issue 899: When [copy-]initializing a temporary to be bound
1740 to the first parameter of a copy constructor (12.8) called with
1741 a single argument in the context of direct-initialization,
1742 explicit conversion functions are also considered.
1744 So don't set LOOKUP_ONLYCONVERTING in that case. */
1745 if (!(flags
& LOOKUP_COPY_PARM
))
1746 flags
|= LOOKUP_ONLYCONVERTING
;
1749 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1754 if (conv
->user_conv_p
)
1756 /* If initializing the temporary used a conversion function,
1757 recalculate the second conversion sequence. */
1758 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1759 if (t
->kind
== ck_user
1760 && DECL_CONV_FN_P (t
->cand
->fn
))
1762 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1763 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1764 conversion
*new_second
1765 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1769 return merge_conversion_sequences (t
, new_second
);
1773 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1774 /* This reference binding, unlike those above, requires the
1775 creation of a temporary. */
1776 conv
->need_temporary_p
= true;
1777 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1781 Otherwise, the reference shall be an lvalue reference to a
1782 non-volatile const type, or the reference shall be an rvalue
1784 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1789 Otherwise, a temporary of type "cv1 T1" is created and
1790 initialized from the initializer expression using the rules for a
1791 non-reference copy initialization. If T1 is reference-related to
1792 T2, cv1 must be the same cv-qualification as, or greater
1793 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1794 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1800 /* Returns the implicit conversion sequence (see [over.ics]) from type
1801 FROM to type TO. The optional expression EXPR may affect the
1802 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1803 true, this conversion is coming from a C-style cast. */
1806 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1807 int flags
, tsubst_flags_t complain
)
1811 if (from
== error_mark_node
|| to
== error_mark_node
1812 || expr
== error_mark_node
)
1815 /* Other flags only apply to the primary function in overload
1816 resolution, or after we've chosen one. */
1817 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1818 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1819 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1821 /* FIXME: actually we don't want warnings either, but we can't just
1822 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1823 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1824 We really ought not to issue that warning until we've committed
1825 to that conversion. */
1826 complain
&= ~tf_error
;
1828 /* Call reshape_init early to remove redundant braces. */
1829 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1830 && CLASS_TYPE_P (to
)
1831 && COMPLETE_TYPE_P (complete_type (to
))
1832 && !CLASSTYPE_NON_AGGREGATE (to
))
1834 expr
= reshape_init (to
, expr
, complain
);
1835 if (expr
== error_mark_node
)
1837 from
= TREE_TYPE (expr
);
1840 if (TREE_CODE (to
) == REFERENCE_TYPE
)
1841 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1843 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1848 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1850 if (is_std_init_list (to
))
1851 return build_list_conv (to
, expr
, flags
, complain
);
1853 /* As an extension, allow list-initialization of _Complex. */
1854 if (TREE_CODE (to
) == COMPLEX_TYPE
)
1856 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1861 /* Allow conversion from an initializer-list with one element to a
1863 if (SCALAR_TYPE_P (to
))
1865 int nelts
= CONSTRUCTOR_NELTS (expr
);
1869 elt
= build_value_init (to
, tf_none
);
1870 else if (nelts
== 1)
1871 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1873 elt
= error_mark_node
;
1875 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1876 c_cast_p
, flags
, complain
);
1879 conv
->check_narrowing
= true;
1880 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1881 /* Too many levels of braces, i.e. '{{1}}'. */
1886 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1887 return build_array_conv (to
, expr
, flags
, complain
);
1890 if (expr
!= NULL_TREE
1891 && (MAYBE_CLASS_TYPE_P (from
)
1892 || MAYBE_CLASS_TYPE_P (to
))
1893 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1895 struct z_candidate
*cand
;
1897 if (CLASS_TYPE_P (to
)
1898 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1899 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1900 return build_aggr_conv (to
, expr
, flags
, complain
);
1902 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
1905 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
1906 && CONSTRUCTOR_NELTS (expr
) == 1
1907 && !is_list_ctor (cand
->fn
))
1909 /* "If C is not an initializer-list constructor and the
1910 initializer list has a single element of type cv U, where U is
1911 X or a class derived from X, the implicit conversion sequence
1912 has Exact Match rank if U is X, or Conversion rank if U is
1914 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1915 tree elttype
= TREE_TYPE (elt
);
1916 if (reference_related_p (to
, elttype
))
1917 return implicit_conversion (to
, elttype
, elt
,
1918 c_cast_p
, flags
, complain
);
1920 conv
= cand
->second_conv
;
1923 /* We used to try to bind a reference to a temporary here, but that
1924 is now handled after the recursive call to this function at the end
1925 of reference_binding. */
1932 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1933 functions. ARGS will not be changed until a single candidate is
1936 static struct z_candidate
*
1937 add_candidate (struct z_candidate
**candidates
,
1938 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
1939 size_t num_convs
, conversion
**convs
,
1940 tree access_path
, tree conversion_path
,
1941 int viable
, struct rejection_reason
*reason
,
1944 struct z_candidate
*cand
= (struct z_candidate
*)
1945 conversion_obstack_alloc (sizeof (struct z_candidate
));
1948 cand
->first_arg
= first_arg
;
1950 cand
->convs
= convs
;
1951 cand
->num_convs
= num_convs
;
1952 cand
->access_path
= access_path
;
1953 cand
->conversion_path
= conversion_path
;
1954 cand
->viable
= viable
;
1955 cand
->reason
= reason
;
1956 cand
->next
= *candidates
;
1957 cand
->flags
= flags
;
1963 /* Return the number of remaining arguments in the parameter list
1964 beginning with ARG. */
1967 remaining_arguments (tree arg
)
1971 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
1972 arg
= TREE_CHAIN (arg
))
1978 /* Create an overload candidate for the function or method FN called
1979 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1980 FLAGS is passed on to implicit_conversion.
1982 This does not change ARGS.
1984 CTYPE, if non-NULL, is the type we want to pretend this function
1985 comes from for purposes of overload resolution. */
1987 static struct z_candidate
*
1988 add_function_candidate (struct z_candidate
**candidates
,
1989 tree fn
, tree ctype
, tree first_arg
,
1990 const vec
<tree
, va_gc
> *args
, tree access_path
,
1991 tree conversion_path
, int flags
,
1992 tsubst_flags_t complain
)
1994 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
1998 tree orig_first_arg
= first_arg
;
2001 struct rejection_reason
*reason
= NULL
;
2003 /* At this point we should not see any functions which haven't been
2004 explicitly declared, except for friend functions which will have
2005 been found using argument dependent lookup. */
2006 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2008 /* The `this', `in_chrg' and VTT arguments to constructors are not
2009 considered in overload resolution. */
2010 if (DECL_CONSTRUCTOR_P (fn
))
2012 if (ctor_omit_inherited_parms (fn
))
2013 /* Bring back parameters omitted from an inherited ctor. */
2014 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2016 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2017 skip
= num_artificial_parms_for (fn
);
2018 if (skip
> 0 && first_arg
!= NULL_TREE
)
2021 first_arg
= NULL_TREE
;
2027 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2028 convs
= alloc_conversions (len
);
2030 /* 13.3.2 - Viable functions [over.match.viable]
2031 First, to be a viable function, a candidate function shall have enough
2032 parameters to agree in number with the arguments in the list.
2034 We need to check this first; otherwise, checking the ICSes might cause
2035 us to produce an ill-formed template instantiation. */
2037 parmnode
= parmlist
;
2038 for (i
= 0; i
< len
; ++i
)
2040 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2042 parmnode
= TREE_CHAIN (parmnode
);
2045 if ((i
< len
&& parmnode
)
2046 || !sufficient_parms_p (parmnode
))
2048 int remaining
= remaining_arguments (parmnode
);
2050 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2053 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2054 parameter of type "reference to cv C" (including such a constructor
2055 instantiated from a template) is excluded from the set of candidate
2056 functions when used to construct an object of type D with an argument list
2057 containing a single argument if C is reference-related to D. */
2058 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2059 && flag_new_inheriting_ctors
2060 && DECL_INHERITED_CTOR (fn
))
2062 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2063 tree dtype
= DECL_CONTEXT (fn
);
2064 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2065 if (reference_related_p (ptype
, dtype
)
2066 && reference_related_p (btype
, ptype
))
2069 reason
= inherited_ctor_rejection ();
2073 /* Second, for a function to be viable, its constraints must be
2075 if (flag_concepts
&& viable
2076 && !constraints_satisfied_p (fn
))
2078 reason
= constraint_failure (fn
);
2082 /* When looking for a function from a subobject from an implicit
2083 copy/move constructor/operator=, don't consider anything that takes (a
2084 reference to) an unrelated type. See c++/44909 and core 1092. */
2085 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2087 if (DECL_CONSTRUCTOR_P (fn
))
2089 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2090 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2096 parmnode
= chain_index (i
-1, parmlist
);
2097 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2102 /* This only applies at the top level. */
2103 flags
&= ~LOOKUP_DEFAULTED
;
2109 /* Third, for F to be a viable function, there shall exist for each
2110 argument an implicit conversion sequence that converts that argument
2111 to the corresponding parameter of F. */
2113 parmnode
= parmlist
;
2115 for (i
= 0; i
< len
; ++i
)
2117 tree argtype
, to_type
;
2122 if (parmnode
== void_list_node
)
2125 if (i
== 0 && first_arg
!= NULL_TREE
)
2128 arg
= CONST_CAST_TREE (
2129 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2130 argtype
= lvalue_type (arg
);
2132 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2133 && ! DECL_CONSTRUCTOR_P (fn
));
2137 tree parmtype
= TREE_VALUE (parmnode
);
2140 parmnode
= TREE_CHAIN (parmnode
);
2142 /* The type of the implicit object parameter ('this') for
2143 overload resolution is not always the same as for the
2144 function itself; conversion functions are considered to
2145 be members of the class being converted, and functions
2146 introduced by a using-declaration are considered to be
2147 members of the class that uses them.
2149 Since build_over_call ignores the ICS for the `this'
2150 parameter, we can just change the parm type. */
2151 if (ctype
&& is_this
)
2153 parmtype
= cp_build_qualified_type
2154 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2155 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2157 /* If the function has a ref-qualifier, the implicit
2158 object parameter has reference type. */
2159 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2160 parmtype
= cp_build_reference_type (parmtype
, rv
);
2161 /* The special handling of 'this' conversions in compare_ics
2162 does not apply if there is a ref-qualifier. */
2167 parmtype
= build_pointer_type (parmtype
);
2168 /* We don't use build_this here because we don't want to
2169 capture the object argument until we've chosen a
2170 non-static member function. */
2171 arg
= build_address (arg
);
2172 argtype
= lvalue_type (arg
);
2176 /* Core issue 899: When [copy-]initializing a temporary to be bound
2177 to the first parameter of a copy constructor (12.8) called with
2178 a single argument in the context of direct-initialization,
2179 explicit conversion functions are also considered.
2181 So set LOOKUP_COPY_PARM to let reference_binding know that
2182 it's being called in that context. We generalize the above
2183 to handle move constructors and template constructors as well;
2184 the standardese should soon be updated similarly. */
2185 if (ctype
&& i
== 0 && (len
-skip
== 1)
2186 && DECL_CONSTRUCTOR_P (fn
)
2187 && parmtype
!= error_mark_node
2188 && (same_type_ignoring_top_level_qualifiers_p
2189 (non_reference (parmtype
), ctype
)))
2191 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2192 lflags
|= LOOKUP_COPY_PARM
;
2193 /* We allow user-defined conversions within init-lists, but
2194 don't list-initialize the copy parm, as that would mean
2195 using two levels of braces for the same type. */
2196 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2197 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2198 lflags
|= LOOKUP_NO_CONVERSION
;
2201 lflags
|= LOOKUP_ONLYCONVERTING
;
2203 t
= implicit_conversion (parmtype
, argtype
, arg
,
2204 /*c_cast_p=*/false, lflags
, complain
);
2209 t
= build_identity_conv (argtype
, arg
);
2210 t
->ellipsis_p
= true;
2221 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
);
2228 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
);
2233 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2234 access_path
, conversion_path
, viable
, reason
, flags
);
2237 /* Create an overload candidate for the conversion function FN which will
2238 be invoked for expression OBJ, producing a pointer-to-function which
2239 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2240 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2241 passed on to implicit_conversion.
2243 Actually, we don't really care about FN; we care about the type it
2244 converts to. There may be multiple conversion functions that will
2245 convert to that type, and we rely on build_user_type_conversion_1 to
2246 choose the best one; so when we create our candidate, we record the type
2247 instead of the function. */
2249 static struct z_candidate
*
2250 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2251 const vec
<tree
, va_gc
> *arglist
,
2252 tree access_path
, tree conversion_path
,
2253 tsubst_flags_t complain
)
2255 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2256 int i
, len
, viable
, flags
;
2257 tree parmlist
, parmnode
;
2259 struct rejection_reason
*reason
;
2261 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2262 parmlist
= TREE_TYPE (parmlist
);
2263 parmlist
= TYPE_ARG_TYPES (parmlist
);
2265 len
= vec_safe_length (arglist
) + 1;
2266 convs
= alloc_conversions (len
);
2267 parmnode
= parmlist
;
2269 flags
= LOOKUP_IMPLICIT
;
2272 /* Don't bother looking up the same type twice. */
2273 if (*candidates
&& (*candidates
)->fn
== totype
)
2276 for (i
= 0; i
< len
; ++i
)
2278 tree arg
, argtype
, convert_type
= NULL_TREE
;
2284 arg
= (*arglist
)[i
- 1];
2285 argtype
= lvalue_type (arg
);
2289 t
= build_identity_conv (argtype
, NULL_TREE
);
2290 t
= build_conv (ck_user
, totype
, t
);
2291 /* Leave the 'cand' field null; we'll figure out the conversion in
2292 convert_like_real if this candidate is chosen. */
2293 convert_type
= totype
;
2295 else if (parmnode
== void_list_node
)
2299 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2300 /*c_cast_p=*/false, flags
, complain
);
2301 convert_type
= TREE_VALUE (parmnode
);
2305 t
= build_identity_conv (argtype
, arg
);
2306 t
->ellipsis_p
= true;
2307 convert_type
= argtype
;
2317 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
);
2324 parmnode
= TREE_CHAIN (parmnode
);
2328 || ! sufficient_parms_p (parmnode
))
2330 int remaining
= remaining_arguments (parmnode
);
2332 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2335 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2336 access_path
, conversion_path
, viable
, reason
, flags
);
2340 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2341 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2342 int flags
, tsubst_flags_t complain
)
2349 struct rejection_reason
*reason
= NULL
;
2354 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2355 convs
= alloc_conversions (num_convs
);
2357 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2358 conversion ops are allowed. We handle that here by just checking for
2359 boolean_type_node because other operators don't ask for it. COND_EXPR
2360 also does contextual conversion to bool for the first operand, but we
2361 handle that in build_conditional_expr, and type1 here is operand 2. */
2362 if (type1
!= boolean_type_node
)
2363 flags
|= LOOKUP_ONLYCONVERTING
;
2365 for (i
= 0; i
< 2; ++i
)
2370 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2371 /*c_cast_p=*/false, flags
, complain
);
2375 /* We need something for printing the candidate. */
2376 t
= build_identity_conv (types
[i
], NULL_TREE
);
2377 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2383 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2389 /* For COND_EXPR we rearranged the arguments; undo that now. */
2392 convs
[2] = convs
[1];
2393 convs
[1] = convs
[0];
2394 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2395 /*c_cast_p=*/false, flags
,
2402 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2407 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2409 /*access_path=*/NULL_TREE
,
2410 /*conversion_path=*/NULL_TREE
,
2411 viable
, reason
, flags
);
2415 is_complete (tree t
)
2417 return COMPLETE_TYPE_P (complete_type (t
));
2420 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2423 promoted_arithmetic_type_p (tree type
)
2427 In this section, the term promoted integral type is used to refer
2428 to those integral types which are preserved by integral promotion
2429 (including e.g. int and long but excluding e.g. char).
2430 Similarly, the term promoted arithmetic type refers to promoted
2431 integral types plus floating types. */
2432 return ((CP_INTEGRAL_TYPE_P (type
)
2433 && same_type_p (type_promotes_to (type
), type
))
2434 || TREE_CODE (type
) == REAL_TYPE
);
2437 /* Create any builtin operator overload candidates for the operator in
2438 question given the converted operand types TYPE1 and TYPE2. The other
2439 args are passed through from add_builtin_candidates to
2440 build_builtin_candidate.
2442 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2443 If CODE is requires candidates operands of the same type of the kind
2444 of which TYPE1 and TYPE2 are, we add both candidates
2445 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2448 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2449 enum tree_code code2
, tree fnname
, tree type1
,
2450 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2451 tsubst_flags_t complain
)
2455 case POSTINCREMENT_EXPR
:
2456 case POSTDECREMENT_EXPR
:
2457 args
[1] = integer_zero_node
;
2458 type2
= integer_type_node
;
2467 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2468 and VQ is either volatile or empty, there exist candidate operator
2469 functions of the form
2470 VQ T& operator++(VQ T&);
2471 T operator++(VQ T&, int);
2472 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2473 type other than bool, and VQ is either volatile or empty, there exist
2474 candidate operator functions of the form
2475 VQ T& operator--(VQ T&);
2476 T operator--(VQ T&, int);
2477 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2478 complete object type, and VQ is either volatile or empty, there exist
2479 candidate operator functions of the form
2480 T*VQ& operator++(T*VQ&);
2481 T*VQ& operator--(T*VQ&);
2482 T* operator++(T*VQ&, int);
2483 T* operator--(T*VQ&, int); */
2485 case POSTDECREMENT_EXPR
:
2486 case PREDECREMENT_EXPR
:
2487 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2490 case POSTINCREMENT_EXPR
:
2491 case PREINCREMENT_EXPR
:
2492 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2494 type1
= build_reference_type (type1
);
2499 /* 7 For every cv-qualified or cv-unqualified object type T, there
2500 exist candidate operator functions of the form
2504 8 For every function type T, there exist candidate operator functions of
2506 T& operator*(T*); */
2509 if (TYPE_PTR_P (type1
)
2510 && (TYPE_PTROB_P (type1
)
2511 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2515 /* 9 For every type T, there exist candidate operator functions of the form
2518 10For every promoted arithmetic type T, there exist candidate operator
2519 functions of the form
2523 case UNARY_PLUS_EXPR
: /* unary + */
2524 if (TYPE_PTR_P (type1
))
2528 if (ARITHMETIC_TYPE_P (type1
))
2532 /* 11For every promoted integral type T, there exist candidate operator
2533 functions of the form
2537 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2541 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2542 is the same type as C2 or is a derived class of C2, T is a complete
2543 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2544 there exist candidate operator functions of the form
2545 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2546 where CV12 is the union of CV1 and CV2. */
2549 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2551 tree c1
= TREE_TYPE (type1
);
2552 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2554 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2555 && (TYPE_PTRMEMFUNC_P (type2
)
2556 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2561 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2562 didate operator functions of the form
2567 bool operator<(L, R);
2568 bool operator>(L, R);
2569 bool operator<=(L, R);
2570 bool operator>=(L, R);
2571 bool operator==(L, R);
2572 bool operator!=(L, R);
2573 where LR is the result of the usual arithmetic conversions between
2576 14For every pair of types T and I, where T is a cv-qualified or cv-
2577 unqualified complete object type and I is a promoted integral type,
2578 there exist candidate operator functions of the form
2579 T* operator+(T*, I);
2580 T& operator[](T*, I);
2581 T* operator-(T*, I);
2582 T* operator+(I, T*);
2583 T& operator[](I, T*);
2585 15For every T, where T is a pointer to complete object type, there exist
2586 candidate operator functions of the form112)
2587 ptrdiff_t operator-(T, T);
2589 16For every pointer or enumeration type T, there exist candidate operator
2590 functions of the form
2591 bool operator<(T, T);
2592 bool operator>(T, T);
2593 bool operator<=(T, T);
2594 bool operator>=(T, T);
2595 bool operator==(T, T);
2596 bool operator!=(T, T);
2598 17For every pointer to member type T, there exist candidate operator
2599 functions of the form
2600 bool operator==(T, T);
2601 bool operator!=(T, T); */
2604 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2606 if (TYPE_PTROB_P (type1
)
2607 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2609 type2
= ptrdiff_type_node
;
2614 case TRUNC_DIV_EXPR
:
2615 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2621 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2622 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2624 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2629 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2641 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2643 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2645 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2646 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2648 if (TYPE_PTR_P (type1
)
2649 && null_ptr_cst_p (args
[1]))
2654 if (null_ptr_cst_p (args
[0])
2655 && TYPE_PTR_P (type2
))
2663 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2667 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2669 type1
= ptrdiff_type_node
;
2672 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2674 type2
= ptrdiff_type_node
;
2679 /* 18For every pair of promoted integral types L and R, there exist candi-
2680 date operator functions of the form
2687 where LR is the result of the usual arithmetic conversions between
2690 case TRUNC_MOD_EXPR
:
2696 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2700 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2701 type, VQ is either volatile or empty, and R is a promoted arithmetic
2702 type, there exist candidate operator functions of the form
2703 VQ L& operator=(VQ L&, R);
2704 VQ L& operator*=(VQ L&, R);
2705 VQ L& operator/=(VQ L&, R);
2706 VQ L& operator+=(VQ L&, R);
2707 VQ L& operator-=(VQ L&, R);
2709 20For every pair T, VQ), where T is any type and VQ is either volatile
2710 or empty, there exist candidate operator functions of the form
2711 T*VQ& operator=(T*VQ&, T*);
2713 21For every pair T, VQ), where T is a pointer to member type and VQ is
2714 either volatile or empty, there exist candidate operator functions of
2716 VQ T& operator=(VQ T&, T);
2718 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2719 unqualified complete object type, VQ is either volatile or empty, and
2720 I is a promoted integral type, there exist candidate operator func-
2722 T*VQ& operator+=(T*VQ&, I);
2723 T*VQ& operator-=(T*VQ&, I);
2725 23For every triple L, VQ, R), where L is an integral or enumeration
2726 type, VQ is either volatile or empty, and R is a promoted integral
2727 type, there exist candidate operator functions of the form
2729 VQ L& operator%=(VQ L&, R);
2730 VQ L& operator<<=(VQ L&, R);
2731 VQ L& operator>>=(VQ L&, R);
2732 VQ L& operator&=(VQ L&, R);
2733 VQ L& operator^=(VQ L&, R);
2734 VQ L& operator|=(VQ L&, R); */
2741 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2743 type2
= ptrdiff_type_node
;
2748 case TRUNC_DIV_EXPR
:
2749 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2753 case TRUNC_MOD_EXPR
:
2759 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2764 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2766 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2767 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2768 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2769 || ((TYPE_PTRMEMFUNC_P (type1
)
2770 || TYPE_PTR_P (type1
))
2771 && null_ptr_cst_p (args
[1])))
2781 type1
= build_reference_type (type1
);
2787 For every pair of promoted arithmetic types L and R, there
2788 exist candidate operator functions of the form
2790 LR operator?(bool, L, R);
2792 where LR is the result of the usual arithmetic conversions
2793 between types L and R.
2795 For every type T, where T is a pointer or pointer-to-member
2796 type, there exist candidate operator functions of the form T
2797 operator?(bool, T, T); */
2799 if (promoted_arithmetic_type_p (type1
)
2800 && promoted_arithmetic_type_p (type2
))
2804 /* Otherwise, the types should be pointers. */
2805 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2808 /* We don't check that the two types are the same; the logic
2809 below will actually create two candidates; one in which both
2810 parameter types are TYPE1, and one in which both parameter
2816 if (ARITHMETIC_TYPE_P (type1
))
2824 /* Make sure we don't create builtin candidates with dependent types. */
2825 bool u1
= uses_template_parms (type1
);
2826 bool u2
= type2
? uses_template_parms (type2
) : false;
2829 /* Try to recover if one of the types is non-dependent. But if
2830 there's only one type, there's nothing we can do. */
2833 /* And we lose if both are dependent. */
2836 /* Or if they have different forms. */
2837 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2846 /* If we're dealing with two pointer types or two enumeral types,
2847 we need candidates for both of them. */
2848 if (type2
&& !same_type_p (type1
, type2
)
2849 && TREE_CODE (type1
) == TREE_CODE (type2
)
2850 && (TREE_CODE (type1
) == REFERENCE_TYPE
2851 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2852 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2853 || TYPE_PTRMEMFUNC_P (type1
)
2854 || MAYBE_CLASS_TYPE_P (type1
)
2855 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2857 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2859 tree cptype
= composite_pointer_type (type1
, type2
,
2864 if (cptype
!= error_mark_node
)
2866 build_builtin_candidate
2867 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
2873 build_builtin_candidate
2874 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
2875 build_builtin_candidate
2876 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
2880 build_builtin_candidate
2881 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
2885 type_decays_to (tree type
)
2887 if (TREE_CODE (type
) == ARRAY_TYPE
)
2888 return build_pointer_type (TREE_TYPE (type
));
2889 if (TREE_CODE (type
) == FUNCTION_TYPE
)
2890 return build_pointer_type (type
);
2894 /* There are three conditions of builtin candidates:
2896 1) bool-taking candidates. These are the same regardless of the input.
2897 2) pointer-pair taking candidates. These are generated for each type
2898 one of the input types converts to.
2899 3) arithmetic candidates. According to the standard, we should generate
2900 all of these, but I'm trying not to...
2902 Here we generate a superset of the possible candidates for this particular
2903 case. That is a subset of the full set the standard defines, plus some
2904 other cases which the standard disallows. add_builtin_candidate will
2905 filter out the invalid set. */
2908 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
2909 enum tree_code code2
, tree fnname
, tree
*args
,
2910 int flags
, tsubst_flags_t complain
)
2914 tree type
, argtypes
[3], t
;
2915 /* TYPES[i] is the set of possible builtin-operator parameter types
2916 we will consider for the Ith argument. */
2917 vec
<tree
, va_gc
> *types
[2];
2920 for (i
= 0; i
< 3; ++i
)
2923 argtypes
[i
] = unlowered_expr_type (args
[i
]);
2925 argtypes
[i
] = NULL_TREE
;
2930 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2931 and VQ is either volatile or empty, there exist candidate operator
2932 functions of the form
2933 VQ T& operator++(VQ T&); */
2935 case POSTINCREMENT_EXPR
:
2936 case PREINCREMENT_EXPR
:
2937 case POSTDECREMENT_EXPR
:
2938 case PREDECREMENT_EXPR
:
2943 /* 24There also exist candidate operator functions of the form
2944 bool operator!(bool);
2945 bool operator&&(bool, bool);
2946 bool operator||(bool, bool); */
2948 case TRUTH_NOT_EXPR
:
2949 build_builtin_candidate
2950 (candidates
, fnname
, boolean_type_node
,
2951 NULL_TREE
, args
, argtypes
, flags
, complain
);
2954 case TRUTH_ORIF_EXPR
:
2955 case TRUTH_ANDIF_EXPR
:
2956 build_builtin_candidate
2957 (candidates
, fnname
, boolean_type_node
,
2958 boolean_type_node
, args
, argtypes
, flags
, complain
);
2980 types
[0] = make_tree_vector ();
2981 types
[1] = make_tree_vector ();
2983 for (i
= 0; i
< 2; ++i
)
2987 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
2991 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
2994 convs
= lookup_conversions (argtypes
[i
]);
2996 if (code
== COND_EXPR
)
2998 if (lvalue_p (args
[i
]))
2999 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3001 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3007 for (; convs
; convs
= TREE_CHAIN (convs
))
3009 type
= TREE_TYPE (convs
);
3012 && (TREE_CODE (type
) != REFERENCE_TYPE
3013 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3016 if (code
== COND_EXPR
&& TREE_CODE (type
) == REFERENCE_TYPE
)
3017 vec_safe_push (types
[i
], type
);
3019 type
= non_reference (type
);
3020 if (i
!= 0 || ! ref1
)
3022 type
= cv_unqualified (type_decays_to (type
));
3023 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3024 vec_safe_push (types
[i
], type
);
3025 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3026 type
= type_promotes_to (type
);
3029 if (! vec_member (type
, types
[i
]))
3030 vec_safe_push (types
[i
], type
);
3035 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3036 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3037 type
= non_reference (argtypes
[i
]);
3038 if (i
!= 0 || ! ref1
)
3040 type
= cv_unqualified (type_decays_to (type
));
3041 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3042 vec_safe_push (types
[i
], type
);
3043 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3044 type
= type_promotes_to (type
);
3046 vec_safe_push (types
[i
], type
);
3050 /* Run through the possible parameter types of both arguments,
3051 creating candidates with those parameter types. */
3052 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3057 if (!types
[1]->is_empty ())
3058 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3059 add_builtin_candidate
3060 (candidates
, code
, code2
, fnname
, t
,
3061 u
, args
, argtypes
, flags
, complain
);
3063 add_builtin_candidate
3064 (candidates
, code
, code2
, fnname
, t
,
3065 NULL_TREE
, args
, argtypes
, flags
, complain
);
3068 release_tree_vector (types
[0]);
3069 release_tree_vector (types
[1]);
3073 /* If TMPL can be successfully instantiated as indicated by
3074 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3076 TMPL is the template. EXPLICIT_TARGS are any explicit template
3077 arguments. ARGLIST is the arguments provided at the call-site.
3078 This does not change ARGLIST. The RETURN_TYPE is the desired type
3079 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3080 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3081 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3083 static struct z_candidate
*
3084 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3085 tree ctype
, tree explicit_targs
, tree first_arg
,
3086 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3087 tree access_path
, tree conversion_path
,
3088 int flags
, tree obj
, unification_kind_t strict
,
3089 tsubst_flags_t complain
)
3091 int ntparms
= DECL_NTPARMS (tmpl
);
3092 tree targs
= make_tree_vec (ntparms
);
3093 unsigned int len
= vec_safe_length (arglist
);
3094 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3095 unsigned int skip_without_in_chrg
= 0;
3096 tree first_arg_without_in_chrg
= first_arg
;
3097 tree
*args_without_in_chrg
;
3098 unsigned int nargs_without_in_chrg
;
3099 unsigned int ia
, ix
;
3101 struct z_candidate
*cand
;
3103 struct rejection_reason
*reason
= NULL
;
3106 /* We don't do deduction on the in-charge parameter, the VTT
3107 parameter or 'this'. */
3108 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3110 if (first_arg_without_in_chrg
!= NULL_TREE
)
3111 first_arg_without_in_chrg
= NULL_TREE
;
3112 else if (return_type
&& strict
== DEDUCE_CALL
)
3113 /* We're deducing for a call to the result of a template conversion
3114 function, so the args don't contain 'this'; leave them alone. */;
3116 ++skip_without_in_chrg
;
3119 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3120 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3121 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3123 if (first_arg_without_in_chrg
!= NULL_TREE
)
3124 first_arg_without_in_chrg
= NULL_TREE
;
3126 ++skip_without_in_chrg
;
3129 if (len
< skip_without_in_chrg
)
3132 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3133 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3134 TREE_TYPE ((*arglist
)[0])))
3136 /* 12.8/6 says, "A declaration of a constructor for a class X is
3137 ill-formed if its first parameter is of type (optionally cv-qualified)
3138 X and either there are no other parameters or else all other
3139 parameters have default arguments. A member function template is never
3140 instantiated to produce such a constructor signature."
3142 So if we're trying to copy an object of the containing class, don't
3143 consider a template constructor that has a first parameter type that
3144 is just a template parameter, as we would deduce a signature that we
3145 would then reject in the code below. */
3146 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3148 firstparm
= TREE_VALUE (firstparm
);
3149 if (PACK_EXPANSION_P (firstparm
))
3150 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3151 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3153 gcc_assert (!explicit_targs
);
3154 reason
= invalid_copy_with_fn_template_rejection ();
3160 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3161 + (len
- skip_without_in_chrg
));
3162 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3164 if (first_arg_without_in_chrg
!= NULL_TREE
)
3166 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3169 for (ix
= skip_without_in_chrg
;
3170 vec_safe_iterate (arglist
, ix
, &arg
);
3173 args_without_in_chrg
[ia
] = arg
;
3176 gcc_assert (ia
== nargs_without_in_chrg
);
3178 errs
= errorcount
+sorrycount
;
3179 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3180 args_without_in_chrg
,
3181 nargs_without_in_chrg
,
3182 return_type
, strict
, flags
, false,
3183 complain
& tf_decltype
);
3185 if (fn
== error_mark_node
)
3187 /* Don't repeat unification later if it already resulted in errors. */
3188 if (errorcount
+sorrycount
== errs
)
3189 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3190 targs
, args_without_in_chrg
,
3191 nargs_without_in_chrg
,
3192 return_type
, strict
, flags
);
3194 reason
= template_unification_error_rejection ();
3198 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3200 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3201 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3204 /* We're trying to produce a constructor with a prohibited signature,
3205 as discussed above; handle here any cases we didn't catch then,
3207 reason
= invalid_copy_with_fn_template_rejection ();
3212 if (obj
!= NULL_TREE
)
3213 /* Aha, this is a conversion function. */
3214 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3215 access_path
, conversion_path
, complain
);
3217 cand
= add_function_candidate (candidates
, fn
, ctype
,
3218 first_arg
, arglist
, access_path
,
3219 conversion_path
, flags
, complain
);
3220 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3221 /* This situation can occur if a member template of a template
3222 class is specialized. Then, instantiate_template might return
3223 an instantiation of the specialization, in which case the
3224 DECL_TI_TEMPLATE field will point at the original
3225 specialization. For example:
3227 template <class T> struct S { template <class U> void f(U);
3228 template <> void f(int) {}; };
3232 Here, TMPL will be template <class U> S<double>::f(U).
3233 And, instantiate template will give us the specialization
3234 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3235 for this will point at template <class T> template <> S<T>::f(int),
3236 so that we can find the definition. For the purposes of
3237 overload resolution, however, we want the original TMPL. */
3238 cand
->template_decl
= build_template_info (tmpl
, targs
);
3240 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3241 cand
->explicit_targs
= explicit_targs
;
3245 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3246 access_path
, conversion_path
, 0, reason
, flags
);
3250 static struct z_candidate
*
3251 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3252 tree explicit_targs
, tree first_arg
,
3253 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3254 tree access_path
, tree conversion_path
, int flags
,
3255 unification_kind_t strict
, tsubst_flags_t complain
)
3258 add_template_candidate_real (candidates
, tmpl
, ctype
,
3259 explicit_targs
, first_arg
, arglist
,
3260 return_type
, access_path
, conversion_path
,
3261 flags
, NULL_TREE
, strict
, complain
);
3264 /* Create an overload candidate for the conversion function template TMPL,
3265 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3266 pointer-to-function which will in turn be called with the argument list
3267 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3268 passed on to implicit_conversion. */
3270 static struct z_candidate
*
3271 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3273 const vec
<tree
, va_gc
> *arglist
,
3274 tree return_type
, tree access_path
,
3275 tree conversion_path
, tsubst_flags_t complain
)
3277 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3278 core issue 2189, let's disable this candidate if there are any call
3284 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3285 NULL_TREE
, arglist
, return_type
, access_path
,
3286 conversion_path
, 0, obj
, DEDUCE_CALL
,
3290 /* The CANDS are the set of candidates that were considered for
3291 overload resolution. Return the set of viable candidates, or CANDS
3292 if none are viable. If any of the candidates were viable, set
3293 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3294 considered viable only if it is strictly viable. */
3296 static struct z_candidate
*
3297 splice_viable (struct z_candidate
*cands
,
3301 struct z_candidate
*viable
;
3302 struct z_candidate
**last_viable
;
3303 struct z_candidate
**cand
;
3304 bool found_strictly_viable
= false;
3306 /* Be strict inside templates, since build_over_call won't actually
3307 do the conversions to get pedwarns. */
3308 if (processing_template_decl
)
3312 last_viable
= &viable
;
3313 *any_viable_p
= false;
3318 struct z_candidate
*c
= *cand
;
3320 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3322 /* Be strict in the presence of a viable candidate. Also if
3323 there are template candidates, so that we get deduction errors
3324 for them instead of silently preferring a bad conversion. */
3326 if (viable
&& !found_strictly_viable
)
3328 /* Put any spliced near matches back onto the main list so
3329 that we see them if there is no strict match. */
3330 *any_viable_p
= false;
3331 *last_viable
= cands
;
3334 last_viable
= &viable
;
3338 if (strict_p
? c
->viable
== 1 : c
->viable
)
3343 last_viable
= &c
->next
;
3344 *any_viable_p
= true;
3346 found_strictly_viable
= true;
3352 return viable
? viable
: cands
;
3356 any_strictly_viable (struct z_candidate
*cands
)
3358 for (; cands
; cands
= cands
->next
)
3359 if (cands
->viable
== 1)
3364 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3365 words, it is about to become the "this" pointer for a member
3366 function call. Take the address of the object. */
3369 build_this (tree obj
)
3371 /* In a template, we are only concerned about the type of the
3372 expression, so we can take a shortcut. */
3373 if (processing_template_decl
)
3374 return build_address (obj
);
3376 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3379 /* Returns true iff functions are equivalent. Equivalent functions are
3380 not '==' only if one is a function-local extern function or if
3381 both are extern "C". */
3384 equal_functions (tree fn1
, tree fn2
)
3386 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3388 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3390 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3391 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3392 return decls_match (fn1
, fn2
);
3396 /* Print information about a candidate being rejected due to INFO. */
3399 print_conversion_rejection (location_t loc
, struct conversion_info
*info
)
3401 tree from
= info
->from
;
3403 from
= lvalue_type (from
);
3404 if (info
->n_arg
== -1)
3406 /* Conversion of implicit `this' argument failed. */
3407 if (!TYPE_P (info
->from
))
3408 /* A bad conversion for 'this' must be discarding cv-quals. */
3409 inform (loc
, " passing %qT as %<this%> "
3410 "argument discards qualifiers",
3413 inform (loc
, " no known conversion for implicit "
3414 "%<this%> parameter from %qH to %qI",
3415 from
, info
->to_type
);
3417 else if (!TYPE_P (info
->from
))
3419 if (info
->n_arg
>= 0)
3420 inform (loc
, " conversion of argument %d would be ill-formed:",
3422 perform_implicit_conversion (info
->to_type
, info
->from
,
3423 tf_warning_or_error
);
3425 else if (info
->n_arg
== -2)
3426 /* Conversion of conversion function return value failed. */
3427 inform (loc
, " no known conversion from %qH to %qI",
3428 from
, info
->to_type
);
3430 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3431 info
->n_arg
+ 1, from
, info
->to_type
);
3434 /* Print information about a candidate with WANT parameters and we found
3438 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3440 inform_n (loc
, want
,
3441 " candidate expects %d argument, %d provided",
3442 " candidate expects %d arguments, %d provided",
3446 /* Print information about one overload candidate CANDIDATE. MSGSTR
3447 is the text to print before the candidate itself.
3449 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3450 to have been run through gettext by the caller. This wart makes
3451 life simpler in print_z_candidates and for the translators. */
3454 print_z_candidate (location_t loc
, const char *msgstr
,
3455 struct z_candidate
*candidate
)
3457 const char *msg
= (msgstr
== NULL
3459 : ACONCAT ((msgstr
, " ", NULL
)));
3460 tree fn
= candidate
->fn
;
3461 if (flag_new_inheriting_ctors
)
3462 fn
= strip_inheriting_ctors (fn
);
3463 location_t cloc
= location_of (fn
);
3465 if (identifier_p (fn
))
3468 if (candidate
->num_convs
== 3)
3469 inform (cloc
, "%s%<%D(%T, %T, %T)%> <built-in>", msg
, fn
,
3470 candidate
->convs
[0]->type
,
3471 candidate
->convs
[1]->type
,
3472 candidate
->convs
[2]->type
);
3473 else if (candidate
->num_convs
== 2)
3474 inform (cloc
, "%s%<%D(%T, %T)%> <built-in>", msg
, fn
,
3475 candidate
->convs
[0]->type
,
3476 candidate
->convs
[1]->type
);
3478 inform (cloc
, "%s%<%D(%T)%> <built-in>", msg
, fn
,
3479 candidate
->convs
[0]->type
);
3481 else if (TYPE_P (fn
))
3482 inform (cloc
, "%s%qT <conversion>", msg
, fn
);
3483 else if (candidate
->viable
== -1)
3484 inform (cloc
, "%s%#qD <near match>", msg
, fn
);
3485 else if (DECL_DELETED_FN (fn
))
3486 inform (cloc
, "%s%#qD <deleted>", msg
, fn
);
3488 inform (cloc
, "%s%#qD", msg
, fn
);
3489 if (fn
!= candidate
->fn
)
3491 cloc
= location_of (candidate
->fn
);
3492 inform (cloc
, " inherited here");
3494 /* Give the user some information about why this candidate failed. */
3495 if (candidate
->reason
!= NULL
)
3497 struct rejection_reason
*r
= candidate
->reason
;
3502 print_arity_information (cloc
, r
->u
.arity
.actual
,
3503 r
->u
.arity
.expected
);
3505 case rr_arg_conversion
:
3506 print_conversion_rejection (cloc
, &r
->u
.conversion
);
3508 case rr_bad_arg_conversion
:
3509 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
);
3511 case rr_explicit_conversion
:
3512 inform (cloc
, " return type %qT of explicit conversion function "
3513 "cannot be converted to %qT with a qualification "
3514 "conversion", r
->u
.conversion
.from
,
3515 r
->u
.conversion
.to_type
);
3517 case rr_template_conversion
:
3518 inform (cloc
, " conversion from return type %qT of template "
3519 "conversion function specialization to %qT is not an "
3520 "exact match", r
->u
.conversion
.from
,
3521 r
->u
.conversion
.to_type
);
3523 case rr_template_unification
:
3524 /* We use template_unification_error_rejection if unification caused
3525 actual non-SFINAE errors, in which case we don't need to repeat
3527 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3529 inform (cloc
, " substitution of deduced template arguments "
3530 "resulted in errors seen above");
3533 /* Re-run template unification with diagnostics. */
3534 inform (cloc
, " template argument deduction/substitution failed:");
3535 fn_type_unification (r
->u
.template_unification
.tmpl
,
3536 r
->u
.template_unification
.explicit_targs
,
3538 (r
->u
.template_unification
.num_targs
)),
3539 r
->u
.template_unification
.args
,
3540 r
->u
.template_unification
.nargs
,
3541 r
->u
.template_unification
.return_type
,
3542 r
->u
.template_unification
.strict
,
3543 r
->u
.template_unification
.flags
,
3546 case rr_invalid_copy
:
3548 " a constructor taking a single argument of its own "
3549 "class type is invalid");
3551 case rr_constraint_failure
:
3553 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3554 tree args
= r
->u
.template_instantiation
.targs
;
3555 diagnose_constraints (cloc
, tmpl
, args
);
3558 case rr_inherited_ctor
:
3559 inform (cloc
, " an inherited constructor is not a candidate for "
3560 "initialization from an expression of the same or derived "
3565 /* This candidate didn't have any issues or we failed to
3566 handle a particular code. Either way... */
3573 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3575 struct z_candidate
*cand1
;
3576 struct z_candidate
**cand2
;
3581 /* Remove non-viable deleted candidates. */
3583 for (cand2
= &cand1
; *cand2
; )
3585 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3586 && !(*cand2
)->viable
3587 && DECL_DELETED_FN ((*cand2
)->fn
))
3588 *cand2
= (*cand2
)->next
;
3590 cand2
= &(*cand2
)->next
;
3592 /* ...if there are any non-deleted ones. */
3596 /* There may be duplicates in the set of candidates. We put off
3597 checking this condition as long as possible, since we have no way
3598 to eliminate duplicates from a set of functions in less than n^2
3599 time. Now we are about to emit an error message, so it is more
3600 permissible to go slowly. */
3601 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3603 tree fn
= cand1
->fn
;
3604 /* Skip builtin candidates and conversion functions. */
3607 cand2
= &cand1
->next
;
3610 if (DECL_P ((*cand2
)->fn
)
3611 && equal_functions (fn
, (*cand2
)->fn
))
3612 *cand2
= (*cand2
)->next
;
3614 cand2
= &(*cand2
)->next
;
3618 for (; candidates
; candidates
= candidates
->next
)
3619 print_z_candidate (loc
, "candidate:", candidates
);
3622 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3623 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3624 the result of the conversion function to convert it to the final
3625 desired type. Merge the two sequences into a single sequence,
3626 and return the merged sequence. */
3629 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3632 bool bad
= user_seq
->bad_p
;
3634 gcc_assert (user_seq
->kind
== ck_user
);
3636 /* Find the end of the second conversion sequence. */
3637 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3639 /* The entire sequence is a user-conversion sequence. */
3640 (*t
)->user_conv_p
= true;
3645 if ((*t
)->rvaluedness_matches_p
)
3646 /* We're binding a reference directly to the result of the conversion.
3647 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3648 type, but we want it back. */
3649 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3651 /* Replace the identity conversion with the user conversion
3658 /* Handle overload resolution for initializing an object of class type from
3659 an initializer list. First we look for a suitable constructor that
3660 takes a std::initializer_list; if we don't find one, we then look for a
3661 non-list constructor.
3663 Parameters are as for add_candidates, except that the arguments are in
3664 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3665 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3668 add_list_candidates (tree fns
, tree first_arg
,
3669 const vec
<tree
, va_gc
> *args
, tree totype
,
3670 tree explicit_targs
, bool template_only
,
3671 tree conversion_path
, tree access_path
,
3673 struct z_candidate
**candidates
,
3674 tsubst_flags_t complain
)
3676 gcc_assert (*candidates
== NULL
);
3678 /* We're looking for a ctor for list-initialization. */
3679 flags
|= LOOKUP_LIST_INIT_CTOR
;
3680 /* And we don't allow narrowing conversions. We also use this flag to
3681 avoid the copy constructor call for copy-list-initialization. */
3682 flags
|= LOOKUP_NO_NARROWING
;
3684 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3685 tree init_list
= (*args
)[nart
];
3687 /* Always use the default constructor if the list is empty (DR 990). */
3688 if (CONSTRUCTOR_NELTS (init_list
) == 0
3689 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3691 /* If the class has a list ctor, try passing the list as a single
3692 argument first, but only consider list ctors. */
3693 else if (TYPE_HAS_LIST_CTOR (totype
))
3695 flags
|= LOOKUP_LIST_ONLY
;
3696 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3697 explicit_targs
, template_only
, conversion_path
,
3698 access_path
, flags
, candidates
, complain
);
3699 if (any_strictly_viable (*candidates
))
3703 /* Expand the CONSTRUCTOR into a new argument vec. */
3704 vec
<tree
, va_gc
> *new_args
;
3705 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3706 for (unsigned i
= 0; i
< nart
; ++i
)
3707 new_args
->quick_push ((*args
)[i
]);
3708 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3709 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3711 /* We aren't looking for list-ctors anymore. */
3712 flags
&= ~LOOKUP_LIST_ONLY
;
3713 /* We allow more user-defined conversions within an init-list. */
3714 flags
&= ~LOOKUP_NO_CONVERSION
;
3716 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3717 explicit_targs
, template_only
, conversion_path
,
3718 access_path
, flags
, candidates
, complain
);
3721 /* Returns the best overload candidate to perform the requested
3722 conversion. This function is used for three the overloading situations
3723 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3724 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3725 per [dcl.init.ref], so we ignore temporary bindings. */
3727 static struct z_candidate
*
3728 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3729 tsubst_flags_t complain
)
3731 struct z_candidate
*candidates
, *cand
;
3733 tree ctors
= NULL_TREE
;
3734 tree conv_fns
= NULL_TREE
;
3735 conversion
*conv
= NULL
;
3736 tree first_arg
= NULL_TREE
;
3737 vec
<tree
, va_gc
> *args
= NULL
;
3744 fromtype
= TREE_TYPE (expr
);
3746 /* We represent conversion within a hierarchy using RVALUE_CONV and
3747 BASE_CONV, as specified by [over.best.ics]; these become plain
3748 constructor calls, as specified in [dcl.init]. */
3749 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3750 || !DERIVED_FROM_P (totype
, fromtype
));
3752 if (CLASS_TYPE_P (totype
))
3753 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3754 creating a garbage BASELINK; constructors can't be inherited. */
3755 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3757 if (MAYBE_CLASS_TYPE_P (fromtype
))
3759 tree to_nonref
= non_reference (totype
);
3760 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3761 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3762 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3764 /* [class.conv.fct] A conversion function is never used to
3765 convert a (possibly cv-qualified) object to the (possibly
3766 cv-qualified) same object type (or a reference to it), to a
3767 (possibly cv-qualified) base class of that type (or a
3768 reference to it)... */
3771 conv_fns
= lookup_conversions (fromtype
);
3775 flags
|= LOOKUP_NO_CONVERSION
;
3776 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3777 flags
|= LOOKUP_NO_NARROWING
;
3779 /* It's OK to bind a temporary for converting constructor arguments, but
3780 not in converting the return value of a conversion operator. */
3781 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3782 | (flags
& LOOKUP_NO_NARROWING
));
3783 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3787 int ctorflags
= flags
;
3789 first_arg
= build_dummy_object (totype
);
3791 /* We should never try to call the abstract or base constructor
3793 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3794 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3796 args
= make_tree_vector_single (expr
);
3797 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3799 /* List-initialization. */
3800 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3801 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3802 ctorflags
, &candidates
, complain
);
3806 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3807 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3808 ctorflags
, &candidates
, complain
);
3811 for (cand
= candidates
; cand
; cand
= cand
->next
)
3813 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3815 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3816 set, then this is copy-initialization. In that case, "The
3817 result of the call is then used to direct-initialize the
3818 object that is the destination of the copy-initialization."
3821 We represent this in the conversion sequence with an
3822 rvalue conversion, which means a constructor call. */
3823 if (TREE_CODE (totype
) != REFERENCE_TYPE
3824 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3826 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3832 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3833 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3838 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3840 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3841 struct z_candidate
*old_candidates
;
3843 /* If we are called to convert to a reference type, we are trying to
3844 find a direct binding, so don't even consider temporaries. If
3845 we don't find a direct binding, the caller will try again to
3846 look for a temporary binding. */
3847 if (TREE_CODE (totype
) == REFERENCE_TYPE
)
3848 convflags
|= LOOKUP_NO_TEMP_BIND
;
3850 old_candidates
= candidates
;
3851 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3853 conversion_path
, TYPE_BINFO (fromtype
),
3854 flags
, &candidates
, complain
);
3856 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
3858 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
3860 = implicit_conversion (totype
,
3863 /*c_cast_p=*/false, convflags
,
3866 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3867 copy-initialization. In that case, "The result of the
3868 call is then used to direct-initialize the object that is
3869 the destination of the copy-initialization." [dcl.init]
3871 We represent this in the conversion sequence with an
3872 rvalue conversion, which means a constructor call. But
3873 don't add a second rvalue conversion if there's already
3874 one there. Which there really shouldn't be, but it's
3875 harmless since we'd add it here anyway. */
3876 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
3877 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3878 ics
= build_conv (ck_rvalue
, totype
, ics
);
3880 cand
->second_conv
= ics
;
3885 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
3888 else if (DECL_NONCONVERTING_P (cand
->fn
)
3889 && ics
->rank
> cr_exact
)
3891 /* 13.3.1.5: For direct-initialization, those explicit
3892 conversion functions that are not hidden within S and
3893 yield type T or a type that can be converted to type T
3894 with a qualification conversion (4.4) are also candidate
3896 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3897 I've raised this issue with the committee. --jason 9/2011 */
3899 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
3901 else if (cand
->viable
== 1 && ics
->bad_p
)
3905 = bad_arg_conversion_rejection (NULL_TREE
, -2,
3908 else if (primary_template_specialization_p (cand
->fn
)
3909 && ics
->rank
> cr_exact
)
3911 /* 13.3.3.1.2: If the user-defined conversion is specified by
3912 a specialization of a conversion function template, the
3913 second standard conversion sequence shall have exact match
3916 cand
->reason
= template_conversion_rejection (rettype
, totype
);
3921 candidates
= splice_viable (candidates
, false, &any_viable_p
);
3925 release_tree_vector (args
);
3929 cand
= tourney (candidates
, complain
);
3932 if (complain
& tf_error
)
3934 error ("conversion from %qH to %qI is ambiguous",
3936 print_z_candidates (location_of (expr
), candidates
);
3939 cand
= candidates
; /* any one will do */
3940 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
3941 cand
->second_conv
->user_conv_p
= true;
3942 if (!any_strictly_viable (candidates
))
3943 cand
->second_conv
->bad_p
= true;
3944 if (flags
& LOOKUP_ONLYCONVERTING
)
3945 cand
->second_conv
->need_temporary_p
= true;
3946 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3947 ambiguous conversion is no worse than another user-defined
3954 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
3955 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
3956 else if (cand
->second_conv
->kind
== ck_rvalue
)
3957 /* DR 5: [in the first step of copy-initialization]...if the function
3958 is a constructor, the call initializes a temporary of the
3959 cv-unqualified version of the destination type. */
3960 convtype
= cv_unqualified (totype
);
3963 /* Build the user conversion sequence. */
3967 build_identity_conv (TREE_TYPE (expr
), expr
));
3969 if (cand
->viable
== -1)
3972 /* Remember that this was a list-initialization. */
3973 if (flags
& LOOKUP_NO_NARROWING
)
3974 conv
->check_narrowing
= true;
3976 /* Combine it with the second conversion sequence. */
3977 cand
->second_conv
= merge_conversion_sequences (conv
,
3983 /* Wrapper for above. */
3986 build_user_type_conversion (tree totype
, tree expr
, int flags
,
3987 tsubst_flags_t complain
)
3989 struct z_candidate
*cand
;
3992 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
3993 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
3997 if (cand
->second_conv
->kind
== ck_ambig
)
3998 ret
= error_mark_node
;
4001 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4002 ret
= convert_from_reference (expr
);
4008 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4012 /* Subroutine of convert_nontype_argument.
4014 EXPR is an expression used in a context that requires a converted
4015 constant-expression, such as a template non-type parameter. Do any
4016 necessary conversions (that are permitted for converted
4017 constant-expressions) to convert it to the desired type.
4019 If conversion is successful, returns the converted expression;
4020 otherwise, returns error_mark_node. */
4023 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4028 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
4030 if (error_operand_p (expr
))
4031 return error_mark_node
;
4033 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4034 p
= conversion_obstack_alloc (0);
4036 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4038 LOOKUP_IMPLICIT
, complain
);
4040 /* A converted constant expression of type T is an expression, implicitly
4041 converted to type T, where the converted expression is a constant
4042 expression and the implicit conversion sequence contains only
4044 * user-defined conversions,
4045 * lvalue-to-rvalue conversions (7.1),
4046 * array-to-pointer conversions (7.2),
4047 * function-to-pointer conversions (7.3),
4048 * qualification conversions (7.5),
4049 * integral promotions (7.6),
4050 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4051 * null pointer conversions (7.11) from std::nullptr_t,
4052 * null member pointer conversions (7.12) from std::nullptr_t, and
4053 * function pointer conversions (7.13),
4055 and where the reference binding (if any) binds directly. */
4057 for (conversion
*c
= conv
;
4058 conv
&& c
->kind
!= ck_identity
;
4059 c
= next_conversion (c
))
4063 /* A conversion function is OK. If it isn't constexpr, we'll
4064 complain later that the argument isn't constant. */
4066 /* The lvalue-to-rvalue conversion is OK. */
4068 /* Array-to-pointer and function-to-pointer. */
4070 /* Function pointer conversions. */
4072 /* Qualification conversions. */
4077 if (c
->need_temporary_p
)
4079 if (complain
& tf_error
)
4080 error_at (loc
, "initializing %qH with %qI in converted "
4081 "constant expression does not bind directly",
4082 type
, next_conversion (c
)->type
);
4091 t
= next_conversion (c
)->type
;
4092 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4093 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4094 /* Integral promotion or conversion. */
4096 if (NULLPTR_TYPE_P (t
))
4097 /* Conversion from nullptr to pointer or pointer-to-member. */
4100 if (complain
& tf_error
)
4101 error_at (loc
, "conversion from %qH to %qI in a "
4102 "converted constant expression", t
, type
);
4111 /* Avoid confusing convert_nontype_argument by introducing
4112 a redundant conversion to the same reference type. */
4113 if (conv
&& conv
->kind
== ck_ref_bind
4114 && REFERENCE_REF_P (expr
))
4116 tree ref
= TREE_OPERAND (expr
, 0);
4117 if (same_type_p (type
, TREE_TYPE (ref
)))
4122 expr
= convert_like (conv
, expr
, complain
);
4124 expr
= error_mark_node
;
4126 /* Free all the conversions we allocated. */
4127 obstack_free (&conversion_obstack
, p
);
4132 /* Do any initial processing on the arguments to a function call. */
4134 static vec
<tree
, va_gc
> *
4135 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4140 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4142 if (error_operand_p (arg
))
4144 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4146 if (complain
& tf_error
)
4147 error ("invalid use of void expression");
4150 else if (invalid_nonstatic_memfn_p (input_location
, arg
, complain
))
4156 /* Perform overload resolution on FN, which is called with the ARGS.
4158 Return the candidate function selected by overload resolution, or
4159 NULL if the event that overload resolution failed. In the case
4160 that overload resolution fails, *CANDIDATES will be the set of
4161 candidates considered, and ANY_VIABLE_P will be set to true or
4162 false to indicate whether or not any of the candidates were
4165 The ARGS should already have gone through RESOLVE_ARGS before this
4166 function is called. */
4168 static struct z_candidate
*
4169 perform_overload_resolution (tree fn
,
4170 const vec
<tree
, va_gc
> *args
,
4171 struct z_candidate
**candidates
,
4172 bool *any_viable_p
, tsubst_flags_t complain
)
4174 struct z_candidate
*cand
;
4175 tree explicit_targs
;
4178 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4180 explicit_targs
= NULL_TREE
;
4184 *any_viable_p
= true;
4187 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4188 || TREE_CODE (fn
) == TEMPLATE_DECL
4189 || TREE_CODE (fn
) == OVERLOAD
4190 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4192 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4194 explicit_targs
= TREE_OPERAND (fn
, 1);
4195 fn
= TREE_OPERAND (fn
, 0);
4199 /* Add the various candidate functions. */
4200 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4201 explicit_targs
, template_only
,
4202 /*conversion_path=*/NULL_TREE
,
4203 /*access_path=*/NULL_TREE
,
4205 candidates
, complain
);
4207 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4209 cand
= tourney (*candidates
, complain
);
4213 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4217 /* Print an error message about being unable to build a call to FN with
4218 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4219 be located; CANDIDATES is a possibly empty list of such
4223 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4224 struct z_candidate
*candidates
)
4226 tree targs
= NULL_TREE
;
4227 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4229 targs
= TREE_OPERAND (fn
, 1);
4230 fn
= TREE_OPERAND (fn
, 0);
4232 tree name
= OVL_NAME (fn
);
4233 location_t loc
= location_of (name
);
4235 name
= lookup_template_function (name
, targs
);
4237 if (!any_strictly_viable (candidates
))
4238 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4239 name
, build_tree_list_vec (args
));
4241 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4242 name
, build_tree_list_vec (args
));
4244 print_z_candidates (loc
, candidates
);
4247 /* Return an expression for a call to FN (a namespace-scope function,
4248 or a static member function) with the ARGS. This may change
4252 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4253 tsubst_flags_t complain
)
4255 struct z_candidate
*candidates
, *cand
;
4260 if (args
!= NULL
&& *args
!= NULL
)
4262 *args
= resolve_args (*args
, complain
);
4264 return error_mark_node
;
4268 tm_malloc_replacement (fn
);
4270 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4271 p
= conversion_obstack_alloc (0);
4273 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4278 if (complain
& tf_error
)
4280 // If there is a single (non-viable) function candidate,
4281 // let the error be diagnosed by cp_build_function_call_vec.
4282 if (!any_viable_p
&& candidates
&& ! candidates
->next
4283 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4284 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4286 // Otherwise, emit notes for non-viable candidates.
4287 print_error_for_call_failure (fn
, *args
, candidates
);
4289 result
= error_mark_node
;
4293 int flags
= LOOKUP_NORMAL
;
4294 /* If fn is template_id_expr, the call has explicit template arguments
4295 (e.g. func<int>(5)), communicate this info to build_over_call
4296 through flags so that later we can use it to decide whether to warn
4297 about peculiar null pointer conversion. */
4298 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4300 /* If overload resolution selects a specialization of a
4301 function concept for non-dependent template arguments,
4302 the expression is true if the constraints are satisfied
4303 and false otherwise.
4305 NOTE: This is an extension of Concepts Lite TS that
4306 allows constraints to be used in expressions. */
4307 if (flag_concepts
&& !processing_template_decl
)
4309 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4310 tree targs
= DECL_TI_ARGS (cand
->fn
);
4311 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4312 if (DECL_DECLARED_CONCEPT_P (decl
))
4313 return evaluate_function_concept (decl
, targs
);
4316 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4319 result
= build_over_call (cand
, flags
, complain
);
4322 /* Free all the conversions we allocated. */
4323 obstack_free (&conversion_obstack
, p
);
4328 /* Build a call to a global operator new. FNNAME is the name of the
4329 operator (either "operator new" or "operator new[]") and ARGS are
4330 the arguments provided. This may change ARGS. *SIZE points to the
4331 total number of bytes required by the allocation, and is updated if
4332 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4333 be used. If this function determines that no cookie should be
4334 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4335 is not NULL_TREE, it is evaluated before calculating the final
4336 array size, and if it fails, the array size is replaced with
4337 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4338 is non-NULL, it will be set, upon return, to the allocation
4342 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4343 tree
*size
, tree
*cookie_size
,
4344 tree align_arg
, tree size_check
,
4345 tree
*fn
, tsubst_flags_t complain
)
4347 tree original_size
= *size
;
4349 struct z_candidate
*candidates
;
4350 struct z_candidate
*cand
= NULL
;
4355 /* Set to (size_t)-1 if the size check fails. */
4356 if (size_check
!= NULL_TREE
)
4358 tree errval
= TYPE_MAX_VALUE (sizetype
);
4359 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4360 errval
= throw_bad_array_new_length ();
4361 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4362 original_size
, errval
);
4364 vec_safe_insert (*args
, 0, *size
);
4365 *args
= resolve_args (*args
, complain
);
4367 return error_mark_node
;
4373 If this lookup fails to find the name, or if the allocated type
4374 is not a class type, the allocation function's name is looked
4375 up in the global scope.
4377 we disregard block-scope declarations of "operator new". */
4378 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4379 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4383 vec
<tree
, va_gc
>* align_args
4384 = vec_copy_and_insert (*args
, align_arg
, 1);
4385 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4386 &any_viable_p
, tf_none
);
4389 /* If no aligned allocation function matches, try again without the
4393 /* Figure out what function is being called. */
4395 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4398 /* If no suitable function could be found, issue an error message
4402 if (complain
& tf_error
)
4403 print_error_for_call_failure (fns
, *args
, candidates
);
4404 return error_mark_node
;
4407 /* If a cookie is required, add some extra space. Whether
4408 or not a cookie is required cannot be determined until
4409 after we know which function was called. */
4412 bool use_cookie
= true;
4415 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4416 /* Skip the size_t parameter. */
4417 arg_types
= TREE_CHAIN (arg_types
);
4418 /* Check the remaining parameters (if any). */
4420 && TREE_CHAIN (arg_types
) == void_list_node
4421 && same_type_p (TREE_VALUE (arg_types
),
4424 /* If we need a cookie, adjust the number of bytes allocated. */
4427 /* Update the total size. */
4428 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4431 /* Set to (size_t)-1 if the size check fails. */
4432 gcc_assert (size_check
!= NULL_TREE
);
4433 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4434 *size
, TYPE_MAX_VALUE (sizetype
));
4436 /* Update the argument list to reflect the adjusted size. */
4437 (**args
)[0] = *size
;
4440 *cookie_size
= NULL_TREE
;
4443 /* Tell our caller which function we decided to call. */
4447 /* Build the CALL_EXPR. */
4448 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4451 /* Build a new call to operator(). This may change ARGS. */
4454 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4456 struct z_candidate
*candidates
= 0, *cand
;
4457 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4459 tree result
= NULL_TREE
;
4462 obj
= mark_lvalue_use (obj
);
4464 if (error_operand_p (obj
))
4465 return error_mark_node
;
4467 tree type
= TREE_TYPE (obj
);
4469 obj
= prep_operand (obj
);
4471 if (TYPE_PTRMEMFUNC_P (type
))
4473 if (complain
& tf_error
)
4474 /* It's no good looking for an overloaded operator() on a
4475 pointer-to-member-function. */
4476 error ("pointer-to-member function %qE cannot be called without "
4477 "an object; consider using %<.*%> or %<->*%>", obj
);
4478 return error_mark_node
;
4481 if (TYPE_BINFO (type
))
4483 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4484 if (fns
== error_mark_node
)
4485 return error_mark_node
;
4490 if (args
!= NULL
&& *args
!= NULL
)
4492 *args
= resolve_args (*args
, complain
);
4494 return error_mark_node
;
4497 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4498 p
= conversion_obstack_alloc (0);
4502 first_mem_arg
= obj
;
4504 add_candidates (BASELINK_FUNCTIONS (fns
),
4505 first_mem_arg
, *args
, NULL_TREE
,
4507 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4508 LOOKUP_NORMAL
, &candidates
, complain
);
4511 convs
= lookup_conversions (type
);
4513 for (; convs
; convs
= TREE_CHAIN (convs
))
4515 tree totype
= TREE_TYPE (convs
);
4517 if (TYPE_PTRFN_P (totype
)
4518 || TYPE_REFFN_P (totype
)
4519 || (TREE_CODE (totype
) == REFERENCE_TYPE
4520 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4521 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4525 if (DECL_NONCONVERTING_P (fn
))
4528 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4529 add_template_conv_candidate
4530 (&candidates
, fn
, obj
, *args
, totype
,
4531 /*access_path=*/NULL_TREE
,
4532 /*conversion_path=*/NULL_TREE
, complain
);
4534 add_conv_candidate (&candidates
, fn
, obj
,
4535 *args
, /*conversion_path=*/NULL_TREE
,
4536 /*access_path=*/NULL_TREE
, complain
);
4540 /* Be strict here because if we choose a bad conversion candidate, the
4541 errors we get won't mention the call context. */
4542 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4545 if (complain
& tf_error
)
4547 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4548 build_tree_list_vec (*args
));
4549 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4551 result
= error_mark_node
;
4555 cand
= tourney (candidates
, complain
);
4558 if (complain
& tf_error
)
4560 error ("call of %<(%T) (%A)%> is ambiguous",
4561 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4562 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4564 result
= error_mark_node
;
4566 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4567 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4568 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4569 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4572 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4573 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4577 gcc_checking_assert (TYPE_P (cand
->fn
));
4578 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4580 obj
= convert_from_reference (obj
);
4581 result
= cp_build_function_call_vec (obj
, args
, complain
);
4585 /* Free all the conversions we allocated. */
4586 obstack_free (&conversion_obstack
, p
);
4591 /* Wrapper for above. */
4594 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4597 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4598 ret
= build_op_call_1 (obj
, args
, complain
);
4599 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4603 /* Called by op_error to prepare format strings suitable for the error
4604 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4605 and a suffix (controlled by NTYPES). */
4608 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4612 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4613 : G_("no match for "), errmsg
, NULL
);
4616 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4617 else if (ntypes
== 2)
4618 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4620 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4626 op_error (location_t loc
, enum tree_code code
, enum tree_code code2
,
4627 tree arg1
, tree arg2
, tree arg3
, bool match
)
4629 bool assop
= code
== MODIFY_EXPR
;
4630 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4635 if (flag_diagnostics_show_caret
)
4636 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4638 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4640 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4641 "in %<%E ? %E : %E%>"), 3, match
),
4643 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4646 case POSTINCREMENT_EXPR
:
4647 case POSTDECREMENT_EXPR
:
4648 if (flag_diagnostics_show_caret
)
4649 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4650 opname
, TREE_TYPE (arg1
));
4652 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4654 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4658 if (flag_diagnostics_show_caret
)
4659 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4660 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4662 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4664 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4669 if (flag_diagnostics_show_caret
)
4670 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4671 opname
, TREE_TYPE (arg1
));
4673 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4674 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4679 if (flag_diagnostics_show_caret
)
4680 error_at (loc
, op_error_string (G_("%<operator%s%>"), 2, match
),
4681 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4683 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4685 opname
, arg1
, opname
, arg2
,
4686 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4688 if (flag_diagnostics_show_caret
)
4689 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4690 opname
, TREE_TYPE (arg1
));
4692 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4694 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4699 /* Return the implicit conversion sequence that could be used to
4700 convert E1 to E2 in [expr.cond]. */
4703 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4705 tree t1
= non_reference (TREE_TYPE (e1
));
4706 tree t2
= non_reference (TREE_TYPE (e2
));
4712 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4713 implicitly converted (clause _conv_) to the type "lvalue reference to
4714 T2", subject to the constraint that in the conversion the
4715 reference must bind directly (_dcl.init.ref_) to an lvalue.
4717 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4718 implicitly converted to the type "rvalue reference to T2", subject to
4719 the constraint that the reference must bind directly. */
4722 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4723 conv
= implicit_conversion (rtype
,
4727 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4728 |LOOKUP_ONLYCONVERTING
,
4730 if (conv
&& !conv
->bad_p
)
4734 /* If E2 is a prvalue or if neither of the conversions above can be done
4735 and at least one of the operands has (possibly cv-qualified) class
4737 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4742 If E1 and E2 have class type, and the underlying class types are
4743 the same or one is a base class of the other: E1 can be converted
4744 to match E2 if the class of T2 is the same type as, or a base
4745 class of, the class of T1, and the cv-qualification of T2 is the
4746 same cv-qualification as, or a greater cv-qualification than, the
4747 cv-qualification of T1. If the conversion is applied, E1 is
4748 changed to an rvalue of type T2 that still refers to the original
4749 source class object (or the appropriate subobject thereof). */
4750 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4751 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4753 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4755 conv
= build_identity_conv (t1
, e1
);
4756 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4757 TYPE_MAIN_VARIANT (t2
)))
4758 conv
= build_conv (ck_base
, t2
, conv
);
4760 conv
= build_conv (ck_rvalue
, t2
, conv
);
4769 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4770 converted to the type that expression E2 would have if E2 were
4771 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4772 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4773 LOOKUP_IMPLICIT
, complain
);
4776 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4777 arguments to the conditional expression. */
4780 build_conditional_expr_1 (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
4781 tsubst_flags_t complain
)
4785 tree result
= NULL_TREE
;
4786 tree result_type
= NULL_TREE
;
4787 bool is_glvalue
= true;
4788 struct z_candidate
*candidates
= 0;
4789 struct z_candidate
*cand
;
4791 tree orig_arg2
, orig_arg3
;
4793 /* As a G++ extension, the second argument to the conditional can be
4794 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4795 c'.) If the second operand is omitted, make sure it is
4796 calculated only once. */
4799 if (complain
& tf_error
)
4800 pedwarn (loc
, OPT_Wpedantic
,
4801 "ISO C++ forbids omitting the middle term of a ?: expression");
4803 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
4804 warn_for_omitted_condop (loc
, arg1
);
4806 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4807 if (lvalue_p (arg1
))
4808 arg2
= arg1
= cp_stabilize_reference (arg1
);
4810 arg2
= arg1
= cp_save_expr (arg1
);
4813 /* If something has already gone wrong, just pass that fact up the
4815 if (error_operand_p (arg1
)
4816 || error_operand_p (arg2
)
4817 || error_operand_p (arg3
))
4818 return error_mark_node
;
4823 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
4825 tree arg1_type
= TREE_TYPE (arg1
);
4827 /* If arg1 is another cond_expr choosing between -1 and 0,
4828 then we can use its comparison. It may help to avoid
4829 additional comparison, produce more accurate diagnostics
4830 and enables folding. */
4831 if (TREE_CODE (arg1
) == VEC_COND_EXPR
4832 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
4833 && integer_zerop (TREE_OPERAND (arg1
, 2)))
4834 arg1
= TREE_OPERAND (arg1
, 0);
4836 arg1
= force_rvalue (arg1
, complain
);
4837 arg2
= force_rvalue (arg2
, complain
);
4838 arg3
= force_rvalue (arg3
, complain
);
4840 /* force_rvalue can return error_mark on valid arguments. */
4841 if (error_operand_p (arg1
)
4842 || error_operand_p (arg2
)
4843 || error_operand_p (arg3
))
4844 return error_mark_node
;
4846 arg2_type
= TREE_TYPE (arg2
);
4847 arg3_type
= TREE_TYPE (arg3
);
4849 if (!VECTOR_TYPE_P (arg2_type
)
4850 && !VECTOR_TYPE_P (arg3_type
))
4852 /* Rely on the error messages of the scalar version. */
4853 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
4854 orig_arg2
, orig_arg3
, complain
);
4855 if (scal
== error_mark_node
)
4856 return error_mark_node
;
4857 tree stype
= TREE_TYPE (scal
);
4858 tree ctype
= TREE_TYPE (arg1_type
);
4859 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
4860 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
4862 if (complain
& tf_error
)
4863 error_at (loc
, "inferred scalar type %qT is not an integer or "
4864 "floating point type of the same size as %qT", stype
,
4865 COMPARISON_CLASS_P (arg1
)
4866 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
4868 return error_mark_node
;
4871 tree vtype
= build_opaque_vector_type (stype
,
4872 TYPE_VECTOR_SUBPARTS (arg1_type
));
4873 /* We could pass complain & tf_warning to unsafe_conversion_p,
4874 but the warnings (like Wsign-conversion) have already been
4875 given by the scalar build_conditional_expr_1. We still check
4876 unsafe_conversion_p to forbid truncating long long -> float. */
4877 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
4879 if (complain
& tf_error
)
4880 error_at (loc
, "conversion of scalar %qH to vector %qI "
4881 "involves truncation", arg2_type
, vtype
);
4882 return error_mark_node
;
4884 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
4886 if (complain
& tf_error
)
4887 error_at (loc
, "conversion of scalar %qH to vector %qI "
4888 "involves truncation", arg3_type
, vtype
);
4889 return error_mark_node
;
4892 arg2
= cp_convert (stype
, arg2
, complain
);
4893 arg2
= save_expr (arg2
);
4894 arg2
= build_vector_from_val (vtype
, arg2
);
4896 arg3
= cp_convert (stype
, arg3
, complain
);
4897 arg3
= save_expr (arg3
);
4898 arg3
= build_vector_from_val (vtype
, arg3
);
4902 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
4904 enum stv_conv convert_flag
=
4905 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
4906 complain
& tf_error
);
4908 switch (convert_flag
)
4911 return error_mark_node
;
4914 arg2
= save_expr (arg2
);
4915 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
4916 arg2
= build_vector_from_val (arg3_type
, arg2
);
4917 arg2_type
= TREE_TYPE (arg2
);
4922 arg3
= save_expr (arg3
);
4923 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
4924 arg3
= build_vector_from_val (arg2_type
, arg3
);
4925 arg3_type
= TREE_TYPE (arg3
);
4933 if (!same_type_p (arg2_type
, arg3_type
)
4934 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
4935 TYPE_VECTOR_SUBPARTS (arg2_type
))
4936 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
4938 if (complain
& tf_error
)
4940 "incompatible vector types in conditional expression: "
4941 "%qT, %qT and %qT", TREE_TYPE (arg1
),
4942 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
4943 return error_mark_node
;
4946 if (!COMPARISON_CLASS_P (arg1
))
4948 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
4949 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
4951 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
4956 The first expression is implicitly converted to bool (clause
4958 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
4960 if (error_operand_p (arg1
))
4961 return error_mark_node
;
4965 If either the second or the third operand has type (possibly
4966 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4967 array-to-pointer (_conv.array_), and function-to-pointer
4968 (_conv.func_) standard conversions are performed on the second
4969 and third operands. */
4970 arg2_type
= unlowered_expr_type (arg2
);
4971 arg3_type
= unlowered_expr_type (arg3
);
4972 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
4974 /* Do the conversions. We don't these for `void' type arguments
4975 since it can't have any effect and since decay_conversion
4976 does not handle that case gracefully. */
4977 if (!VOID_TYPE_P (arg2_type
))
4978 arg2
= decay_conversion (arg2
, complain
);
4979 if (!VOID_TYPE_P (arg3_type
))
4980 arg3
= decay_conversion (arg3
, complain
);
4981 arg2_type
= TREE_TYPE (arg2
);
4982 arg3_type
= TREE_TYPE (arg3
);
4986 One of the following shall hold:
4988 --The second or the third operand (but not both) is a
4989 throw-expression (_except.throw_); the result is of the
4990 type of the other and is an rvalue.
4992 --Both the second and the third operands have type void; the
4993 result is of type void and is an rvalue.
4995 We must avoid calling force_rvalue for expressions of type
4996 "void" because it will complain that their value is being
4998 if (TREE_CODE (arg2
) == THROW_EXPR
4999 && TREE_CODE (arg3
) != THROW_EXPR
)
5001 if (!VOID_TYPE_P (arg3_type
))
5003 arg3
= force_rvalue (arg3
, complain
);
5004 if (arg3
== error_mark_node
)
5005 return error_mark_node
;
5007 arg3_type
= TREE_TYPE (arg3
);
5008 result_type
= arg3_type
;
5010 else if (TREE_CODE (arg2
) != THROW_EXPR
5011 && TREE_CODE (arg3
) == THROW_EXPR
)
5013 if (!VOID_TYPE_P (arg2_type
))
5015 arg2
= force_rvalue (arg2
, complain
);
5016 if (arg2
== error_mark_node
)
5017 return error_mark_node
;
5019 arg2_type
= TREE_TYPE (arg2
);
5020 result_type
= arg2_type
;
5022 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5023 result_type
= void_type_node
;
5026 if (complain
& tf_error
)
5028 if (VOID_TYPE_P (arg2_type
))
5029 error_at (EXPR_LOC_OR_LOC (arg3
, loc
),
5030 "second operand to the conditional operator "
5031 "is of type %<void%>, but the third operand is "
5032 "neither a throw-expression nor of type %<void%>");
5034 error_at (EXPR_LOC_OR_LOC (arg2
, loc
),
5035 "third operand to the conditional operator "
5036 "is of type %<void%>, but the second operand is "
5037 "neither a throw-expression nor of type %<void%>");
5039 return error_mark_node
;
5043 goto valid_operands
;
5047 Otherwise, if the second and third operand have different types,
5048 and either has (possibly cv-qualified) class type, or if both are
5049 glvalues of the same value category and the same type except for
5050 cv-qualification, an attempt is made to convert each of those operands
5051 to the type of the other. */
5052 else if (!same_type_p (arg2_type
, arg3_type
)
5053 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5054 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5056 && glvalue_p (arg2
) && glvalue_p (arg3
)
5057 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5061 bool converted
= false;
5063 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5064 p
= conversion_obstack_alloc (0);
5066 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5067 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5071 If both can be converted, or one can be converted but the
5072 conversion is ambiguous, the program is ill-formed. If
5073 neither can be converted, the operands are left unchanged and
5074 further checking is performed as described below. If exactly
5075 one conversion is possible, that conversion is applied to the
5076 chosen operand and the converted operand is used in place of
5077 the original operand for the remainder of this section. */
5078 if ((conv2
&& !conv2
->bad_p
5079 && conv3
&& !conv3
->bad_p
)
5080 || (conv2
&& conv2
->kind
== ck_ambig
)
5081 || (conv3
&& conv3
->kind
== ck_ambig
))
5083 if (complain
& tf_error
)
5085 error_at (loc
, "operands to ?: have different types %qT and %qT",
5086 arg2_type
, arg3_type
);
5087 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5088 inform (loc
, " and each type can be converted to the other");
5089 else if (conv2
&& conv2
->kind
== ck_ambig
)
5090 convert_like (conv2
, arg2
, complain
);
5092 convert_like (conv3
, arg3
, complain
);
5094 result
= error_mark_node
;
5096 else if (conv2
&& !conv2
->bad_p
)
5098 arg2
= convert_like (conv2
, arg2
, complain
);
5099 arg2
= convert_from_reference (arg2
);
5100 arg2_type
= TREE_TYPE (arg2
);
5101 /* Even if CONV2 is a valid conversion, the result of the
5102 conversion may be invalid. For example, if ARG3 has type
5103 "volatile X", and X does not have a copy constructor
5104 accepting a "volatile X&", then even if ARG2 can be
5105 converted to X, the conversion will fail. */
5106 if (error_operand_p (arg2
))
5107 result
= error_mark_node
;
5110 else if (conv3
&& !conv3
->bad_p
)
5112 arg3
= convert_like (conv3
, arg3
, complain
);
5113 arg3
= convert_from_reference (arg3
);
5114 arg3_type
= TREE_TYPE (arg3
);
5115 if (error_operand_p (arg3
))
5116 result
= error_mark_node
;
5120 /* Free all the conversions we allocated. */
5121 obstack_free (&conversion_obstack
, p
);
5126 /* If, after the conversion, both operands have class type,
5127 treat the cv-qualification of both operands as if it were the
5128 union of the cv-qualification of the operands.
5130 The standard is not clear about what to do in this
5131 circumstance. For example, if the first operand has type
5132 "const X" and the second operand has a user-defined
5133 conversion to "volatile X", what is the type of the second
5134 operand after this step? Making it be "const X" (matching
5135 the first operand) seems wrong, as that discards the
5136 qualification without actually performing a copy. Leaving it
5137 as "volatile X" seems wrong as that will result in the
5138 conditional expression failing altogether, even though,
5139 according to this step, the one operand could be converted to
5140 the type of the other. */
5142 && CLASS_TYPE_P (arg2_type
)
5143 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5144 arg2_type
= arg3_type
=
5145 cp_build_qualified_type (arg2_type
,
5146 cp_type_quals (arg2_type
)
5147 | cp_type_quals (arg3_type
));
5152 If the second and third operands are glvalues of the same value
5153 category and have the same type, the result is of that type and
5155 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5156 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5157 && same_type_p (arg2_type
, arg3_type
))
5159 result_type
= arg2_type
;
5160 if (processing_template_decl
)
5161 /* Let lvalue_kind know this was a glvalue. */
5162 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg2
));
5164 arg2
= mark_lvalue_use (arg2
);
5165 arg3
= mark_lvalue_use (arg3
);
5166 goto valid_operands
;
5171 Otherwise, the result is an rvalue. If the second and third
5172 operand do not have the same type, and either has (possibly
5173 cv-qualified) class type, overload resolution is used to
5174 determine the conversions (if any) to be applied to the operands
5175 (_over.match.oper_, _over.built_). */
5177 if (!same_type_p (arg2_type
, arg3_type
)
5178 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5184 /* Rearrange the arguments so that add_builtin_candidate only has
5185 to know about two args. In build_builtin_candidate, the
5186 arguments are unscrambled. */
5190 add_builtin_candidates (&candidates
,
5193 ovl_op_identifier (false, COND_EXPR
),
5195 LOOKUP_NORMAL
, complain
);
5199 If the overload resolution fails, the program is
5201 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5204 if (complain
& tf_error
)
5205 error_at (loc
, "operands to ?: have different types %qT and %qT",
5206 arg2_type
, arg3_type
);
5207 return error_mark_node
;
5209 cand
= tourney (candidates
, complain
);
5212 if (complain
& tf_error
)
5214 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5215 print_z_candidates (loc
, candidates
);
5217 return error_mark_node
;
5222 Otherwise, the conversions thus determined are applied, and
5223 the converted operands are used in place of the original
5224 operands for the remainder of this section. */
5225 conv
= cand
->convs
[0];
5226 arg1
= convert_like (conv
, arg1
, complain
);
5227 conv
= cand
->convs
[1];
5228 arg2
= convert_like (conv
, arg2
, complain
);
5229 arg2_type
= TREE_TYPE (arg2
);
5230 conv
= cand
->convs
[2];
5231 arg3
= convert_like (conv
, arg3
, complain
);
5232 arg3_type
= TREE_TYPE (arg3
);
5237 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5238 and function-to-pointer (_conv.func_) standard conversions are
5239 performed on the second and third operands.
5241 We need to force the lvalue-to-rvalue conversion here for class types,
5242 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5243 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5246 arg2
= force_rvalue (arg2
, complain
);
5247 if (!CLASS_TYPE_P (arg2_type
))
5248 arg2_type
= TREE_TYPE (arg2
);
5250 arg3
= force_rvalue (arg3
, complain
);
5251 if (!CLASS_TYPE_P (arg3_type
))
5252 arg3_type
= TREE_TYPE (arg3
);
5254 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5255 return error_mark_node
;
5259 After those conversions, one of the following shall hold:
5261 --The second and third operands have the same type; the result is of
5263 if (same_type_p (arg2_type
, arg3_type
))
5264 result_type
= arg2_type
;
5267 --The second and third operands have arithmetic or enumeration
5268 type; the usual arithmetic conversions are performed to bring
5269 them to a common type, and the result is of that type. */
5270 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5271 || UNSCOPED_ENUM_P (arg2_type
))
5272 && (ARITHMETIC_TYPE_P (arg3_type
)
5273 || UNSCOPED_ENUM_P (arg3_type
)))
5275 /* In this case, there is always a common type. */
5276 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5278 if (complain
& tf_warning
)
5279 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5280 "implicit conversion from %qH to %qI to "
5281 "match other result of conditional",
5284 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5285 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5287 if (TREE_CODE (orig_arg2
) == CONST_DECL
5288 && TREE_CODE (orig_arg3
) == CONST_DECL
5289 && DECL_CONTEXT (orig_arg2
) == DECL_CONTEXT (orig_arg3
))
5290 /* Two enumerators from the same enumeration can have different
5291 types when the enumeration is still being defined. */;
5292 else if (complain
& tf_warning
)
5293 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5294 "conditional expression: %qT vs %qT",
5295 arg2_type
, arg3_type
);
5297 else if (extra_warnings
5298 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5299 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5300 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5301 && !same_type_p (arg2_type
,
5302 type_promotes_to (arg3_type
)))))
5304 if (complain
& tf_warning
)
5305 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5306 "conditional expression");
5309 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5310 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5314 --The second and third operands have pointer type, or one has
5315 pointer type and the other is a null pointer constant; pointer
5316 conversions (_conv.ptr_) and qualification conversions
5317 (_conv.qual_) are performed to bring them to their composite
5318 pointer type (_expr.rel_). The result is of the composite
5321 --The second and third operands have pointer to member type, or
5322 one has pointer to member type and the other is a null pointer
5323 constant; pointer to member conversions (_conv.mem_) and
5324 qualification conversions (_conv.qual_) are performed to bring
5325 them to a common type, whose cv-qualification shall match the
5326 cv-qualification of either the second or the third operand.
5327 The result is of the common type. */
5328 else if ((null_ptr_cst_p (arg2
)
5329 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5330 || (null_ptr_cst_p (arg3
)
5331 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5332 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5333 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5334 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5336 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5337 arg3
, CPO_CONDITIONAL_EXPR
,
5339 if (result_type
== error_mark_node
)
5340 return error_mark_node
;
5341 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5342 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5347 if (complain
& tf_error
)
5348 error_at (loc
, "operands to ?: have different types %qT and %qT",
5349 arg2_type
, arg3_type
);
5350 return error_mark_node
;
5353 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5354 return error_mark_node
;
5357 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5359 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5360 warn here, because the COND_EXPR will be turned into ARG2. */
5361 if (warn_duplicated_branches
5362 && (complain
& tf_warning
)
5363 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5364 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5365 "this condition has identical branches");
5367 /* We can't use result_type below, as fold might have returned a
5372 /* Expand both sides into the same slot, hopefully the target of
5373 the ?: expression. We used to check for TARGET_EXPRs here,
5374 but now we sometimes wrap them in NOP_EXPRs so the test would
5376 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5377 result
= get_target_expr_sfinae (result
, complain
);
5378 /* If this expression is an rvalue, but might be mistaken for an
5379 lvalue, we must add a NON_LVALUE_EXPR. */
5380 result
= rvalue (result
);
5383 result
= force_paren_expr (result
);
5388 /* Wrapper for above. */
5391 build_conditional_expr (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
5392 tsubst_flags_t complain
)
5395 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5396 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5397 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5401 /* OPERAND is an operand to an expression. Perform necessary steps
5402 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5406 prep_operand (tree operand
)
5410 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5411 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5412 /* Make sure the template type is instantiated now. */
5413 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5419 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5420 OVERLOAD) to the CANDIDATES, returning an updated list of
5421 CANDIDATES. The ARGS are the arguments provided to the call;
5422 if FIRST_ARG is non-null it is the implicit object argument,
5423 otherwise the first element of ARGS is used if needed. The
5424 EXPLICIT_TARGS are explicit template arguments provided.
5425 TEMPLATE_ONLY is true if only template functions should be
5426 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5427 add_function_candidate. */
5430 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5432 tree explicit_targs
, bool template_only
,
5433 tree conversion_path
, tree access_path
,
5435 struct z_candidate
**candidates
,
5436 tsubst_flags_t complain
)
5439 const vec
<tree
, va_gc
> *non_static_args
;
5440 bool check_list_ctor
= false;
5441 bool check_converting
= false;
5442 unification_kind_t strict
;
5447 /* Precalculate special handling of constructors and conversion ops. */
5448 tree fn
= OVL_FIRST (fns
);
5449 if (DECL_CONV_FN_P (fn
))
5451 check_list_ctor
= false;
5452 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5453 if (flags
& LOOKUP_NO_CONVERSION
)
5454 /* We're doing return_type(x). */
5455 strict
= DEDUCE_CONV
;
5457 /* We're doing x.operator return_type(). */
5458 strict
= DEDUCE_EXACT
;
5459 /* [over.match.funcs] For conversion functions, the function
5460 is considered to be a member of the class of the implicit
5461 object argument for the purpose of defining the type of
5462 the implicit object parameter. */
5463 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5467 if (DECL_CONSTRUCTOR_P (fn
))
5469 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5470 /* For list-initialization we consider explicit constructors
5471 and complain if one is chosen. */
5473 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5474 == LOOKUP_ONLYCONVERTING
);
5476 strict
= DEDUCE_CALL
;
5477 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5481 non_static_args
= args
;
5483 /* Delay creating the implicit this parameter until it is needed. */
5484 non_static_args
= NULL
;
5486 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5490 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5492 if (check_list_ctor
&& !is_list_ctor (fn
))
5495 tree fn_first_arg
= NULL_TREE
;
5496 const vec
<tree
, va_gc
> *fn_args
= args
;
5498 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5500 /* Figure out where the object arg comes from. If this
5501 function is a non-static member and we didn't get an
5502 implicit object argument, move it out of args. */
5503 if (first_arg
== NULL_TREE
)
5507 vec
<tree
, va_gc
> *tempvec
;
5508 vec_alloc (tempvec
, args
->length () - 1);
5509 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5510 tempvec
->quick_push (arg
);
5511 non_static_args
= tempvec
;
5512 first_arg
= (*args
)[0];
5515 fn_first_arg
= first_arg
;
5516 fn_args
= non_static_args
;
5519 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5520 add_template_candidate (candidates
,
5532 else if (!template_only
)
5533 add_function_candidate (candidates
,
5545 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5546 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5549 op_is_ordered (tree_code code
)
5555 return (flag_strong_eval_order
> 1 ? -1 : 0);
5559 return (flag_strong_eval_order
> 1 ? 1 : 0);
5562 // Not overloadable (yet).
5564 // Only one argument.
5571 return (flag_strong_eval_order
? 1 : 0);
5579 build_new_op_1 (location_t loc
, enum tree_code code
, int flags
, tree arg1
,
5580 tree arg2
, tree arg3
, tree
*overload
, tsubst_flags_t complain
)
5582 struct z_candidate
*candidates
= 0, *cand
;
5583 vec
<tree
, va_gc
> *arglist
;
5585 tree result
= NULL_TREE
;
5586 bool result_valid_p
= false;
5587 enum tree_code code2
= NOP_EXPR
;
5588 enum tree_code code_orig_arg1
= ERROR_MARK
;
5589 enum tree_code code_orig_arg2
= ERROR_MARK
;
5595 if (error_operand_p (arg1
)
5596 || error_operand_p (arg2
)
5597 || error_operand_p (arg3
))
5598 return error_mark_node
;
5600 bool ismodop
= code
== MODIFY_EXPR
;
5603 code2
= TREE_CODE (arg3
);
5606 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5608 arg1
= prep_operand (arg1
);
5610 bool memonly
= false;
5615 case VEC_DELETE_EXPR
:
5617 /* Use build_op_new_call and build_op_delete_call instead. */
5621 /* Use build_op_call instead. */
5624 case TRUTH_ORIF_EXPR
:
5625 case TRUTH_ANDIF_EXPR
:
5626 case TRUTH_AND_EXPR
:
5628 /* These are saved for the sake of warn_logical_operator. */
5629 code_orig_arg1
= TREE_CODE (arg1
);
5630 code_orig_arg2
= TREE_CODE (arg2
);
5638 /* These are saved for the sake of maybe_warn_bool_compare. */
5639 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5640 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5643 /* =, ->, [], () must be non-static member functions. */
5645 if (code2
!= NOP_EXPR
)
5657 arg2
= prep_operand (arg2
);
5658 arg3
= prep_operand (arg3
);
5660 if (code
== COND_EXPR
)
5661 /* Use build_conditional_expr instead. */
5663 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5664 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5667 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5668 arg2
= integer_zero_node
;
5670 vec_alloc (arglist
, 3);
5671 arglist
->quick_push (arg1
);
5672 if (arg2
!= NULL_TREE
)
5673 arglist
->quick_push (arg2
);
5674 if (arg3
!= NULL_TREE
)
5675 arglist
->quick_push (arg3
);
5677 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5678 p
= conversion_obstack_alloc (0);
5680 /* Add namespace-scope operators to the list of functions to
5684 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5685 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5686 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5687 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5688 flags
, &candidates
, complain
);
5693 args
[2] = NULL_TREE
;
5695 /* Add class-member operators to the candidate set. */
5696 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5700 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5701 if (fns
== error_mark_node
)
5703 result
= error_mark_node
;
5704 goto user_defined_result_ready
;
5707 add_candidates (BASELINK_FUNCTIONS (fns
),
5708 NULL_TREE
, arglist
, NULL_TREE
,
5710 BASELINK_BINFO (fns
),
5711 BASELINK_ACCESS_BINFO (fns
),
5712 flags
, &candidates
, complain
);
5714 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5715 only non-member functions that have type T1 or reference to
5716 cv-qualified-opt T1 for the first argument, if the first argument
5717 has an enumeration type, or T2 or reference to cv-qualified-opt
5718 T2 for the second argument, if the second argument has an
5719 enumeration type. Filter out those that don't match. */
5720 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5722 struct z_candidate
**candp
, **next
;
5724 for (candp
= &candidates
; *candp
; candp
= next
)
5726 tree parmlist
, parmtype
;
5727 int i
, nargs
= (arg2
? 2 : 1);
5732 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5734 for (i
= 0; i
< nargs
; ++i
)
5736 parmtype
= TREE_VALUE (parmlist
);
5738 if (TREE_CODE (parmtype
) == REFERENCE_TYPE
)
5739 parmtype
= TREE_TYPE (parmtype
);
5740 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5741 && (same_type_ignoring_top_level_qualifiers_p
5742 (TREE_TYPE (args
[i
]), parmtype
)))
5745 parmlist
= TREE_CHAIN (parmlist
);
5748 /* No argument has an appropriate type, so remove this
5749 candidate function from the list. */
5752 *candp
= cand
->next
;
5758 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5765 /* For these, the built-in candidates set is empty
5766 [over.match.oper]/3. We don't want non-strict matches
5767 because exact matches are always possible with built-in
5768 operators. The built-in candidate set for COMPONENT_REF
5769 would be empty too, but since there are no such built-in
5770 operators, we accept non-strict matches for them. */
5779 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5784 case POSTINCREMENT_EXPR
:
5785 case POSTDECREMENT_EXPR
:
5786 /* Don't try anything fancy if we're not allowed to produce
5788 if (!(complain
& tf_error
))
5789 return error_mark_node
;
5791 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5792 distinguish between prefix and postfix ++ and
5793 operator++() was used for both, so we allow this with
5797 const char *msg
= (flag_permissive
)
5798 ? G_("no %<%D(int)%> declared for postfix %qs,"
5799 " trying prefix operator instead")
5800 : G_("no %<%D(int)%> declared for postfix %qs");
5801 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
5804 if (!flag_permissive
)
5805 return error_mark_node
;
5807 if (code
== POSTINCREMENT_EXPR
)
5808 code
= PREINCREMENT_EXPR
;
5810 code
= PREDECREMENT_EXPR
;
5811 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5812 NULL_TREE
, overload
, complain
);
5815 /* The caller will deal with these. */
5820 result_valid_p
= true;
5824 if (complain
& tf_error
)
5826 /* If one of the arguments of the operator represents
5827 an invalid use of member function pointer, try to report
5828 a meaningful error ... */
5829 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
5830 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
5831 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
5832 /* We displayed the error message. */;
5835 /* ... Otherwise, report the more generic
5836 "no matching operator found" error */
5837 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
5838 print_z_candidates (loc
, candidates
);
5841 result
= error_mark_node
;
5847 cand
= tourney (candidates
, complain
);
5850 if (complain
& tf_error
)
5852 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
5853 print_z_candidates (loc
, candidates
);
5855 result
= error_mark_node
;
5857 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
5860 *overload
= cand
->fn
;
5862 if (resolve_args (arglist
, complain
) == NULL
)
5863 result
= error_mark_node
;
5865 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
5867 if (trivial_fn_p (cand
->fn
))
5868 /* There won't be a CALL_EXPR. */;
5869 else if (result
&& result
!= error_mark_node
)
5871 tree call
= extract_call_expr (result
);
5872 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
5874 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
5875 /* This prevents build_new_function_call from discarding this
5876 function during instantiation of the enclosing template. */
5877 KOENIG_LOOKUP_P (call
) = 1;
5879 /* Specify evaluation order as per P0145R2. */
5880 CALL_EXPR_ORDERED_ARGS (call
) = false;
5881 switch (op_is_ordered (code
))
5884 CALL_EXPR_REVERSE_ARGS (call
) = true;
5888 CALL_EXPR_ORDERED_ARGS (call
) = true;
5898 /* Give any warnings we noticed during overload resolution. */
5899 if (cand
->warnings
&& (complain
& tf_warning
))
5901 struct candidate_warning
*w
;
5902 for (w
= cand
->warnings
; w
; w
= w
->next
)
5903 joust (cand
, w
->loser
, 1, complain
);
5906 /* Check for comparison of different enum types. */
5915 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
5916 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
5917 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
5918 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
5919 && (complain
& tf_warning
))
5921 warning (OPT_Wenum_compare
,
5922 "comparison between %q#T and %q#T",
5923 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
5930 /* We need to strip any leading REF_BIND so that bitfields
5931 don't cause errors. This should not remove any important
5932 conversions, because builtins don't apply to class
5933 objects directly. */
5934 conv
= cand
->convs
[0];
5935 if (conv
->kind
== ck_ref_bind
)
5936 conv
= next_conversion (conv
);
5937 arg1
= convert_like (conv
, arg1
, complain
);
5941 conv
= cand
->convs
[1];
5942 if (conv
->kind
== ck_ref_bind
)
5943 conv
= next_conversion (conv
);
5945 arg2
= decay_conversion (arg2
, complain
);
5947 /* We need to call warn_logical_operator before
5948 converting arg2 to a boolean_type, but after
5949 decaying an enumerator to its value. */
5950 if (complain
& tf_warning
)
5951 warn_logical_operator (loc
, code
, boolean_type_node
,
5952 code_orig_arg1
, arg1
,
5953 code_orig_arg2
, arg2
);
5955 arg2
= convert_like (conv
, arg2
, complain
);
5959 conv
= cand
->convs
[2];
5960 if (conv
->kind
== ck_ref_bind
)
5961 conv
= next_conversion (conv
);
5962 arg3
= convert_like (conv
, arg3
, complain
);
5968 user_defined_result_ready
:
5970 /* Free all the conversions we allocated. */
5971 obstack_free (&conversion_obstack
, p
);
5973 if (result
|| result_valid_p
)
5980 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
5983 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
5985 case TRUTH_ANDIF_EXPR
:
5986 case TRUTH_ORIF_EXPR
:
5987 case TRUTH_AND_EXPR
:
5989 if (complain
& tf_warning
)
5990 warn_logical_operator (loc
, code
, boolean_type_node
,
5991 code_orig_arg1
, arg1
,
5992 code_orig_arg2
, arg2
);
6000 if ((complain
& tf_warning
)
6001 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6002 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6003 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6004 if (complain
& tf_warning
&& warn_tautological_compare
)
6005 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6010 case TRUNC_DIV_EXPR
:
6015 case TRUNC_MOD_EXPR
:
6019 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6021 case UNARY_PLUS_EXPR
:
6024 case TRUTH_NOT_EXPR
:
6025 case PREINCREMENT_EXPR
:
6026 case POSTINCREMENT_EXPR
:
6027 case PREDECREMENT_EXPR
:
6028 case POSTDECREMENT_EXPR
:
6032 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6035 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6038 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6042 /* The caller will deal with these. */
6054 /* Wrapper for above. */
6057 build_new_op (location_t loc
, enum tree_code code
, int flags
,
6058 tree arg1
, tree arg2
, tree arg3
,
6059 tree
*overload
, tsubst_flags_t complain
)
6062 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6063 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6064 overload
, complain
);
6065 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6069 /* CALL was returned by some call-building function; extract the actual
6070 CALL_EXPR from any bits that have been tacked on, e.g. by
6071 convert_from_reference. */
6074 extract_call_expr (tree call
)
6076 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6077 call
= TREE_OPERAND (call
, 1);
6078 if (REFERENCE_REF_P (call
))
6079 call
= TREE_OPERAND (call
, 0);
6080 if (TREE_CODE (call
) == TARGET_EXPR
)
6081 call
= TARGET_EXPR_INITIAL (call
);
6082 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6083 || TREE_CODE (call
) == AGGR_INIT_EXPR
6084 || call
== error_mark_node
);
6088 /* Returns true if FN has two parameters, of which the second has type
6092 second_parm_is_size_t (tree fn
)
6094 tree t
= FUNCTION_ARG_CHAIN (fn
);
6095 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6098 if (t
== void_list_node
)
6100 if (aligned_new_threshold
&& t
6101 && same_type_p (TREE_VALUE (t
), align_type_node
)
6102 && TREE_CHAIN (t
) == void_list_node
)
6107 /* True if T, an allocation function, has std::align_val_t as its second
6111 aligned_allocation_fn_p (tree t
)
6113 if (!aligned_new_threshold
)
6116 tree a
= FUNCTION_ARG_CHAIN (t
);
6117 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6120 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6121 function (3.7.4.2 [basic.stc.dynamic.deallocation]) with a parameter of
6122 std::align_val_t. */
6125 aligned_deallocation_fn_p (tree t
)
6127 if (!aligned_new_threshold
)
6130 /* A template instance is never a usual deallocation function,
6131 regardless of its signature. */
6132 if (TREE_CODE (t
) == TEMPLATE_DECL
6133 || primary_template_specialization_p (t
))
6136 tree a
= FUNCTION_ARG_CHAIN (t
);
6137 if (same_type_p (TREE_VALUE (a
), align_type_node
)
6138 && TREE_CHAIN (a
) == void_list_node
)
6140 if (!same_type_p (TREE_VALUE (a
), size_type_node
))
6143 if (a
&& same_type_p (TREE_VALUE (a
), align_type_node
)
6144 && TREE_CHAIN (a
) == void_list_node
)
6149 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
6150 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
6153 usual_deallocation_fn_p (tree t
)
6155 /* A template instance is never a usual deallocation function,
6156 regardless of its signature. */
6157 if (TREE_CODE (t
) == TEMPLATE_DECL
6158 || primary_template_specialization_p (t
))
6161 /* If a class T has a member deallocation function named operator delete
6162 with exactly one parameter, then that function is a usual
6163 (non-placement) deallocation function. If class T does not declare
6164 such an operator delete but does declare a member deallocation
6165 function named operator delete with exactly two parameters, the second
6166 of which has type std::size_t (18.2), then this function is a usual
6167 deallocation function. */
6168 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6169 tree chain
= FUNCTION_ARG_CHAIN (t
);
6172 if (chain
== void_list_node
6173 || ((!global
|| flag_sized_deallocation
)
6174 && second_parm_is_size_t (t
)))
6176 if (aligned_deallocation_fn_p (t
))
6181 /* Build a call to operator delete. This has to be handled very specially,
6182 because the restrictions on what signatures match are different from all
6183 other call instances. For a normal delete, only a delete taking (void *)
6184 or (void *, size_t) is accepted. For a placement delete, only an exact
6185 match with the placement new is accepted.
6187 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6188 ADDR is the pointer to be deleted.
6189 SIZE is the size of the memory block to be deleted.
6190 GLOBAL_P is true if the delete-expression should not consider
6191 class-specific delete operators.
6192 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6194 If this call to "operator delete" is being generated as part to
6195 deallocate memory allocated via a new-expression (as per [expr.new]
6196 which requires that if the initialization throws an exception then
6197 we call a deallocation function), then ALLOC_FN is the allocation
6201 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6202 bool global_p
, tree placement
,
6203 tree alloc_fn
, tsubst_flags_t complain
)
6205 tree fn
= NULL_TREE
;
6206 tree fns
, fnname
, type
, t
;
6208 if (addr
== error_mark_node
)
6209 return error_mark_node
;
6211 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6213 fnname
= ovl_op_identifier (false, code
);
6215 if (CLASS_TYPE_P (type
)
6216 && COMPLETE_TYPE_P (complete_type (type
))
6220 If the result of the lookup is ambiguous or inaccessible, or if
6221 the lookup selects a placement deallocation function, the
6222 program is ill-formed.
6224 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6226 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6227 if (fns
== error_mark_node
)
6228 return error_mark_node
;
6233 if (fns
== NULL_TREE
)
6234 fns
= lookup_name_nonclass (fnname
);
6236 /* Strip const and volatile from addr. */
6237 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6241 /* "A declaration of a placement deallocation function matches the
6242 declaration of a placement allocation function if it has the same
6243 number of parameters and, after parameter transformations (8.3.5),
6244 all parameter types except the first are identical."
6246 So we build up the function type we want and ask instantiate_type
6247 to get it for us. */
6248 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6249 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6250 t
= build_function_type (void_type_node
, t
);
6252 fn
= instantiate_type (t
, fns
, tf_none
);
6253 if (fn
== error_mark_node
)
6256 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6258 /* "If the lookup finds the two-parameter form of a usual deallocation
6259 function (3.7.4.2) and that function, considered as a placement
6260 deallocation function, would have been selected as a match for the
6261 allocation function, the program is ill-formed." */
6262 if (second_parm_is_size_t (fn
))
6264 const char *const msg1
6265 = G_("exception cleanup for this placement new selects "
6266 "non-placement operator delete");
6267 const char *const msg2
6268 = G_("%qD is a usual (non-placement) deallocation "
6269 "function in C++14 (or with -fsized-deallocation)");
6271 /* But if the class has an operator delete (void *), then that is
6272 the usual deallocation function, so we shouldn't complain
6273 about using the operator delete (void *, size_t). */
6274 if (DECL_CLASS_SCOPE_P (fn
))
6275 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6279 if (usual_deallocation_fn_p (elt
)
6280 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6283 /* Before C++14 a two-parameter global deallocation function is
6284 always a placement deallocation function, but warn if
6286 else if (!flag_sized_deallocation
)
6288 if ((complain
& tf_warning
)
6289 && warning (OPT_Wc__14_compat
, msg1
))
6290 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6294 if (complain
& tf_warning_or_error
)
6296 if (permerror (input_location
, msg1
))
6298 /* Only mention C++14 for namespace-scope delete. */
6299 if (DECL_NAMESPACE_SCOPE_P (fn
))
6300 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6302 inform (DECL_SOURCE_LOCATION (fn
),
6303 "%qD is a usual (non-placement) deallocation "
6308 return error_mark_node
;
6313 /* "Any non-placement deallocation function matches a non-placement
6314 allocation function. If the lookup finds a single matching
6315 deallocation function, that function will be called; otherwise, no
6316 deallocation function will be called." */
6317 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6320 if (usual_deallocation_fn_p (elt
))
6328 /* -- If the type has new-extended alignment, a function with a
6329 parameter of type std::align_val_t is preferred; otherwise a
6330 function without such a parameter is preferred. If exactly one
6331 preferred function is found, that function is selected and the
6332 selection process terminates. If more than one preferred
6333 function is found, all non-preferred functions are eliminated
6334 from further consideration. */
6335 if (aligned_new_threshold
)
6337 bool want_align
= type_has_new_extended_alignment (type
);
6338 bool fn_align
= aligned_deallocation_fn_p (fn
);
6339 bool elt_align
= aligned_deallocation_fn_p (elt
);
6341 if (elt_align
!= fn_align
)
6343 if (want_align
== elt_align
)
6349 /* -- If the deallocation functions have class scope, the one
6350 without a parameter of type std::size_t is selected. */
6352 if (DECL_CLASS_SCOPE_P (fn
))
6355 /* -- If the type is complete and if, for the second alternative
6356 (delete array) only, the operand is a pointer to a class type
6357 with a non-trivial destructor or a (possibly multi-dimensional)
6358 array thereof, the function with a parameter of type std::size_t
6361 -- Otherwise, it is unspecified whether a deallocation function
6362 with a parameter of type std::size_t is selected. */
6365 want_size
= COMPLETE_TYPE_P (type
);
6366 if (code
== VEC_DELETE_EXPR
6367 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6368 /* We need a cookie to determine the array size. */
6371 bool fn_size
= second_parm_is_size_t (fn
);
6372 bool elt_size
= second_parm_is_size_t (elt
);
6373 gcc_assert (fn_size
!= elt_size
);
6374 if (want_size
== elt_size
)
6379 /* If we have a matching function, call it. */
6382 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6384 /* If the FN is a member function, make sure that it is
6386 if (BASELINK_P (fns
))
6387 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6390 /* Core issue 901: It's ok to new a type with deleted delete. */
6391 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6396 /* The placement args might not be suitable for overload
6397 resolution at this point, so build the call directly. */
6398 int nargs
= call_expr_nargs (placement
);
6399 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6402 for (i
= 1; i
< nargs
; i
++)
6403 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6404 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6405 return error_mark_node
;
6406 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6411 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6412 args
->quick_push (addr
);
6413 if (second_parm_is_size_t (fn
))
6414 args
->quick_push (size
);
6415 if (aligned_deallocation_fn_p (fn
))
6417 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6418 args
->quick_push (al
);
6420 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6421 release_tree_vector (args
);
6428 If no unambiguous matching deallocation function can be found,
6429 propagating the exception does not cause the object's memory to
6433 if ((complain
& tf_warning
)
6435 warning (0, "no corresponding deallocation function for %qD",
6440 if (complain
& tf_error
)
6441 error ("no suitable %<operator %s%> for %qT",
6442 OVL_OP_INFO (false, code
)->name
, type
);
6443 return error_mark_node
;
6446 /* If the current scope isn't allowed to access DECL along
6447 BASETYPE_PATH, give an error. The most derived class in
6448 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6449 the declaration to use in the error diagnostic. */
6452 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6453 tsubst_flags_t complain
, access_failure_info
*afi
)
6455 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6457 if (flag_new_inheriting_ctors
6458 && DECL_INHERITED_CTOR (decl
))
6460 /* 7.3.3/18: The additional constructors are accessible if they would be
6461 accessible when used to construct an object of the corresponding base
6463 decl
= strip_inheriting_ctors (decl
);
6464 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6465 ba_any
, NULL
, complain
);
6468 if (!accessible_p (basetype_path
, decl
, true))
6470 if (complain
& tf_error
)
6472 if (flag_new_inheriting_ctors
)
6473 diag_decl
= strip_inheriting_ctors (diag_decl
);
6474 if (TREE_PRIVATE (decl
))
6476 error ("%q#D is private within this context", diag_decl
);
6477 inform (DECL_SOURCE_LOCATION (diag_decl
),
6478 "declared private here");
6480 afi
->record_access_failure (basetype_path
, diag_decl
);
6482 else if (TREE_PROTECTED (decl
))
6484 error ("%q#D is protected within this context", diag_decl
);
6485 inform (DECL_SOURCE_LOCATION (diag_decl
),
6486 "declared protected here");
6488 afi
->record_access_failure (basetype_path
, diag_decl
);
6492 error ("%q#D is inaccessible within this context", diag_decl
);
6493 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6495 afi
->record_access_failure (basetype_path
, diag_decl
);
6504 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6505 bitwise or of LOOKUP_* values. If any errors are warnings are
6506 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6507 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6511 build_temp (tree expr
, tree type
, int flags
,
6512 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6515 vec
<tree
, va_gc
> *args
;
6517 *diagnostic_kind
= DK_UNSPECIFIED
;
6519 /* If the source is a packed field, calling the copy constructor will require
6520 binding the field to the reference parameter to the copy constructor, and
6521 we'll end up with an infinite loop. If we can use a bitwise copy, then
6523 if ((lvalue_kind (expr
) & clk_packed
)
6524 && CLASS_TYPE_P (TREE_TYPE (expr
))
6525 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6526 return get_target_expr_sfinae (expr
, complain
);
6528 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6529 args
= make_tree_vector_single (expr
);
6530 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6531 &args
, type
, flags
, complain
);
6532 release_tree_vector (args
);
6533 if (warningcount
+ werrorcount
> savew
)
6534 *diagnostic_kind
= DK_WARNING
;
6535 else if (errorcount
> savee
)
6536 *diagnostic_kind
= DK_ERROR
;
6540 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6541 EXPR is implicitly converted to type TOTYPE.
6542 FN and ARGNUM are used for diagnostics. */
6545 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6547 /* Issue warnings about peculiar, but valid, uses of NULL. */
6548 if (null_node_p (expr
) && TREE_CODE (totype
) != BOOLEAN_TYPE
6549 && ARITHMETIC_TYPE_P (totype
))
6551 source_location loc
=
6552 expansion_point_location_if_in_system_header (input_location
);
6555 warning_at (loc
, OPT_Wconversion_null
,
6556 "passing NULL to non-pointer argument %P of %qD",
6559 warning_at (loc
, OPT_Wconversion_null
,
6560 "converting to non-pointer type %qT from NULL", totype
);
6563 /* Issue warnings if "false" is converted to a NULL pointer */
6564 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6565 && TYPE_PTR_P (totype
))
6568 warning_at (input_location
, OPT_Wconversion_null
,
6569 "converting %<false%> to pointer type for argument %P "
6570 "of %qD", argnum
, fn
);
6572 warning_at (input_location
, OPT_Wconversion_null
,
6573 "converting %<false%> to pointer type %qT", totype
);
6577 /* We gave a diagnostic during a conversion. If this was in the second
6578 standard conversion sequence of a user-defined conversion sequence, say
6579 which user-defined conversion. */
6582 maybe_print_user_conv_context (conversion
*convs
)
6584 if (convs
->user_conv_p
)
6585 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6586 if (t
->kind
== ck_user
)
6588 print_z_candidate (0, " after user-defined conversion:",
6594 /* Locate the parameter with the given index within FNDECL.
6595 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6596 Return the location of the FNDECL itself if there are problems. */
6599 get_fndecl_argument_location (tree fndecl
, int argnum
)
6604 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6605 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6606 i
< argnum
&& param
;
6607 i
++, param
= TREE_CHAIN (param
))
6610 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6611 return the location of FNDECL. */
6613 return DECL_SOURCE_LOCATION (fndecl
);
6615 return DECL_SOURCE_LOCATION (param
);
6618 /* Perform the conversions in CONVS on the expression EXPR. FN and
6619 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6620 indicates the `this' argument of a method. INNER is nonzero when
6621 being called to continue a conversion chain. It is negative when a
6622 reference binding will be applied, positive otherwise. If
6623 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6624 conversions will be emitted if appropriate. If C_CAST_P is true,
6625 this conversion is coming from a C-style cast; in that case,
6626 conversions to inaccessible bases are permitted. */
6629 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6630 bool issue_conversion_warnings
,
6631 bool c_cast_p
, tsubst_flags_t complain
)
6633 tree totype
= convs
->type
;
6634 diagnostic_t diag_kind
;
6636 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6638 if (convs
->bad_p
&& !(complain
& tf_error
))
6639 return error_mark_node
;
6642 && convs
->kind
!= ck_user
6643 && convs
->kind
!= ck_list
6644 && convs
->kind
!= ck_ambig
6645 && (convs
->kind
!= ck_ref_bind
6646 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6647 && (convs
->kind
!= ck_rvalue
6648 || SCALAR_TYPE_P (totype
))
6649 && convs
->kind
!= ck_base
)
6651 bool complained
= false;
6652 conversion
*t
= convs
;
6654 /* Give a helpful error if this is bad because of excess braces. */
6655 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6656 && SCALAR_TYPE_P (totype
)
6657 && CONSTRUCTOR_NELTS (expr
) > 0
6658 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6660 complained
= permerror (loc
, "too many braces around initializer "
6662 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6663 && CONSTRUCTOR_NELTS (expr
) == 1)
6664 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6667 /* Give a helpful error if this is bad because a conversion to bool
6668 from std::nullptr_t requires direct-initialization. */
6669 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6670 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6671 complained
= permerror (loc
, "converting to %qH from %qI requires "
6672 "direct-initialization",
6673 totype
, TREE_TYPE (expr
));
6675 for (; t
; t
= next_conversion (t
))
6677 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6679 complained
= permerror (loc
, "invalid user-defined conversion "
6680 "from %qH to %qI", TREE_TYPE (expr
),
6683 print_z_candidate (loc
, "candidate is:", t
->cand
);
6684 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6685 /*issue_conversion_warnings=*/false,
6688 if (convs
->kind
== ck_ref_bind
)
6689 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6690 LOOKUP_NORMAL
, NULL_TREE
,
6693 expr
= cp_convert (totype
, expr
, complain
);
6694 if (complained
&& fn
)
6695 inform (DECL_SOURCE_LOCATION (fn
),
6696 " initializing argument %P of %qD", argnum
, fn
);
6699 else if (t
->kind
== ck_user
|| !t
->bad_p
)
6701 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6702 /*issue_conversion_warnings=*/false,
6707 else if (t
->kind
== ck_ambig
)
6708 return convert_like_real (t
, expr
, fn
, argnum
,
6709 /*issue_conversion_warnings=*/false,
6712 else if (t
->kind
== ck_identity
)
6716 complained
= permerror (loc
, "invalid conversion from %qH to %qI",
6717 TREE_TYPE (expr
), totype
);
6718 if (complained
&& fn
)
6719 inform (get_fndecl_argument_location (fn
, argnum
),
6720 " initializing argument %P of %qD", argnum
, fn
);
6722 return cp_convert (totype
, expr
, complain
);
6725 if (issue_conversion_warnings
&& (complain
& tf_warning
))
6726 conversion_null_warnings (totype
, expr
, fn
, argnum
);
6728 switch (convs
->kind
)
6732 struct z_candidate
*cand
= convs
->cand
;
6735 /* We chose the surrogate function from add_conv_candidate, now we
6736 actually need to build the conversion. */
6737 cand
= build_user_type_conversion_1 (totype
, expr
,
6738 LOOKUP_NO_CONVERSION
, complain
);
6740 tree convfn
= cand
->fn
;
6742 /* When converting from an init list we consider explicit
6743 constructors, but actually trying to call one is an error. */
6744 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
6745 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
6746 /* Unless this is for direct-list-initialization. */
6747 && !CONSTRUCTOR_IS_DIRECT_INIT (expr
)
6748 /* And in C++98 a default constructor can't be explicit. */
6749 && cxx_dialect
>= cxx11
)
6751 if (!(complain
& tf_error
))
6752 return error_mark_node
;
6753 location_t loc
= location_of (expr
);
6754 if (CONSTRUCTOR_NELTS (expr
) == 0
6755 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
6757 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
6758 "would use explicit constructor %qD",
6760 inform (loc
, "in C++11 and above a default constructor "
6764 error ("converting to %qT from initializer list would use "
6765 "explicit constructor %qD", totype
, convfn
);
6768 /* If we're initializing from {}, it's value-initialization. */
6769 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6770 && CONSTRUCTOR_NELTS (expr
) == 0
6771 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
6773 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
6774 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
6775 return error_mark_node
;
6776 expr
= build_value_init (totype
, complain
);
6777 expr
= get_target_expr_sfinae (expr
, complain
);
6778 if (expr
!= error_mark_node
)
6780 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6781 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
6786 expr
= mark_rvalue_use (expr
);
6788 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
6790 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
6793 /* If this is a constructor or a function returning an aggr type,
6794 we need to build up a TARGET_EXPR. */
6795 if (DECL_CONSTRUCTOR_P (convfn
))
6797 expr
= build_cplus_new (totype
, expr
, complain
);
6799 /* Remember that this was list-initialization. */
6800 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
6801 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6807 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
6809 int nelts
= CONSTRUCTOR_NELTS (expr
);
6811 expr
= build_value_init (totype
, complain
);
6812 else if (nelts
== 1)
6813 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6817 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
6818 /*read_p=*/true, UNKNOWN_LOCATION
,
6819 /*reject_builtin=*/true);
6821 if (type_unknown_p (expr
))
6822 expr
= instantiate_type (totype
, expr
, complain
);
6823 if (expr
== null_node
6824 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
6825 /* If __null has been converted to an integer type, we do not want to
6826 continue to warn about uses of EXPR as an integer, rather than as a
6828 expr
= build_int_cst (totype
, 0);
6831 /* We leave bad_p off ck_ambig because overload resolution considers
6832 it valid, it just fails when we try to perform it. So we need to
6833 check complain here, too. */
6834 if (complain
& tf_error
)
6836 /* Call build_user_type_conversion again for the error. */
6837 int flags
= (convs
->need_temporary_p
6838 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
6839 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
6840 gcc_assert (seen_error ());
6842 inform (DECL_SOURCE_LOCATION (fn
),
6843 " initializing argument %P of %qD", argnum
, fn
);
6845 return error_mark_node
;
6849 /* Conversion to std::initializer_list<T>. */
6850 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
6851 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
6852 unsigned len
= CONSTRUCTOR_NELTS (expr
);
6853 tree array
, val
, field
;
6854 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
6857 /* Convert all the elements. */
6858 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
6860 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
, argnum
,
6861 false, false, complain
);
6862 if (sub
== error_mark_node
)
6864 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
6865 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
6866 return error_mark_node
;
6867 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
), NULL_TREE
, sub
);
6868 if (!TREE_CONSTANT (sub
))
6869 TREE_CONSTANT (new_ctor
) = false;
6871 /* Build up the array. */
6872 elttype
= cp_build_qualified_type
6873 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
6874 array
= build_array_of_n_type (elttype
, len
);
6875 array
= finish_compound_literal (array
, new_ctor
, complain
);
6876 /* Take the address explicitly rather than via decay_conversion
6877 to avoid the error about taking the address of a temporary. */
6878 array
= cp_build_addr_expr (array
, complain
);
6879 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
6880 if (array
== error_mark_node
)
6881 return error_mark_node
;
6883 /* Build up the initializer_list object. */
6884 totype
= complete_type (totype
);
6885 field
= next_initializable_field (TYPE_FIELDS (totype
));
6886 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
6887 field
= next_initializable_field (DECL_CHAIN (field
));
6888 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
6889 new_ctor
= build_constructor (totype
, vec
);
6890 return get_target_expr_sfinae (new_ctor
, complain
);
6894 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
6896 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6897 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
6898 real
= perform_implicit_conversion (TREE_TYPE (totype
),
6900 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
6902 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
6905 expr
= reshape_init (totype
, expr
, complain
);
6906 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
6908 if (expr
!= error_mark_node
)
6909 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6916 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
6917 convs
->kind
== ck_ref_bind
6918 ? issue_conversion_warnings
: false,
6919 c_cast_p
, complain
);
6920 if (expr
== error_mark_node
)
6921 return error_mark_node
;
6923 switch (convs
->kind
)
6926 expr
= decay_conversion (expr
, complain
);
6927 if (expr
== error_mark_node
)
6929 if (complain
& tf_error
)
6931 maybe_print_user_conv_context (convs
);
6933 inform (DECL_SOURCE_LOCATION (fn
),
6934 " initializing argument %P of %qD", argnum
, fn
);
6936 return error_mark_node
;
6939 if (! MAYBE_CLASS_TYPE_P (totype
))
6942 /* Don't introduce copies when passing arguments along to the inherited
6944 if (current_function_decl
6945 && flag_new_inheriting_ctors
6946 && DECL_INHERITED_CTOR (current_function_decl
))
6949 if (TREE_CODE (expr
) == TARGET_EXPR
6950 && TARGET_EXPR_LIST_INIT_P (expr
))
6951 /* Copy-list-initialization doesn't actually involve a copy. */
6956 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
6958 /* We are going to bind a reference directly to a base-class
6959 subobject of EXPR. */
6960 /* Build an expression for `*((base*) &expr)'. */
6961 expr
= convert_to_base (expr
, totype
,
6962 !c_cast_p
, /*nonnull=*/true, complain
);
6966 /* Copy-initialization where the cv-unqualified version of the source
6967 type is the same class as, or a derived class of, the class of the
6968 destination [is treated as direct-initialization]. [dcl.init] */
6969 flags
= LOOKUP_NORMAL
;
6970 if (convs
->user_conv_p
)
6971 /* This conversion is being done in the context of a user-defined
6972 conversion (i.e. the second step of copy-initialization), so
6973 don't allow any more. */
6974 flags
|= LOOKUP_NO_CONVERSION
;
6976 flags
|= LOOKUP_ONLYCONVERTING
;
6977 if (convs
->rvaluedness_matches_p
)
6978 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
6979 flags
|= LOOKUP_PREFER_RVALUE
;
6980 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
6981 if (diag_kind
&& complain
)
6983 maybe_print_user_conv_context (convs
);
6985 inform (DECL_SOURCE_LOCATION (fn
),
6986 " initializing argument %P of %qD", argnum
, fn
);
6989 return build_cplus_new (totype
, expr
, complain
);
6993 tree ref_type
= totype
;
6995 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
6997 tree extype
= TREE_TYPE (expr
);
6998 if (TYPE_REF_IS_RVALUE (ref_type
)
7000 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7001 "lvalue of type %qI", totype
, extype
);
7002 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7003 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7004 error_at (loc
, "cannot bind non-const lvalue reference of "
7005 "type %qH to an rvalue of type %qI", totype
, extype
);
7006 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7007 error_at (loc
, "binding reference of type %qH to %qI "
7008 "discards qualifiers", totype
, extype
);
7011 maybe_print_user_conv_context (convs
);
7013 inform (DECL_SOURCE_LOCATION (fn
),
7014 " initializing argument %P of %qD", argnum
, fn
);
7015 return error_mark_node
;
7018 /* If necessary, create a temporary.
7020 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7021 that need temporaries, even when their types are reference
7022 compatible with the type of reference being bound, so the
7023 upcoming call to cp_build_addr_expr doesn't fail. */
7024 if (convs
->need_temporary_p
7025 || TREE_CODE (expr
) == CONSTRUCTOR
7026 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7028 /* Otherwise, a temporary of type "cv1 T1" is created and
7029 initialized from the initializer expression using the rules
7030 for a non-reference copy-initialization (8.5). */
7032 tree type
= TREE_TYPE (ref_type
);
7033 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7035 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7036 (type
, next_conversion (convs
)->type
));
7037 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7038 && !TYPE_REF_IS_RVALUE (ref_type
))
7040 /* If the reference is volatile or non-const, we
7041 cannot create a temporary. */
7042 if (lvalue
& clk_bitfield
)
7043 error_at (loc
, "cannot bind bitfield %qE to %qT",
7045 else if (lvalue
& clk_packed
)
7046 error_at (loc
, "cannot bind packed field %qE to %qT",
7049 error_at (loc
, "cannot bind rvalue %qE to %qT",
7051 return error_mark_node
;
7053 /* If the source is a packed field, and we must use a copy
7054 constructor, then building the target expr will require
7055 binding the field to the reference parameter to the
7056 copy constructor, and we'll end up with an infinite
7057 loop. If we can use a bitwise copy, then we'll be
7059 if ((lvalue
& clk_packed
)
7060 && CLASS_TYPE_P (type
)
7061 && type_has_nontrivial_copy_init (type
))
7063 error_at (loc
, "cannot bind packed field %qE to %qT",
7065 return error_mark_node
;
7067 if (lvalue
& clk_bitfield
)
7069 expr
= convert_bitfield_to_declared_type (expr
);
7070 expr
= fold_convert (type
, expr
);
7072 expr
= build_target_expr_with_type (expr
, type
, complain
);
7075 /* Take the address of the thing to which we will bind the
7077 expr
= cp_build_addr_expr (expr
, complain
);
7078 if (expr
== error_mark_node
)
7079 return error_mark_node
;
7081 /* Convert it to a pointer to the type referred to by the
7082 reference. This will adjust the pointer if a derived to
7083 base conversion is being performed. */
7084 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7086 /* Convert the pointer to the desired reference type. */
7087 return build_nop (ref_type
, expr
);
7091 return decay_conversion (expr
, complain
);
7094 /* ??? Should the address of a transaction-safe pointer point to the TM
7095 clone, and this conversion look up the primary function? */
7096 return build_nop (totype
, expr
);
7099 /* Warn about deprecated conversion if appropriate. */
7100 string_conv_p (totype
, expr
, 1);
7105 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7106 /*nonnull=*/false, complain
);
7107 return build_nop (totype
, expr
);
7110 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7111 c_cast_p
, complain
);
7117 if (convs
->check_narrowing
7118 && !check_narrowing (totype
, expr
, complain
))
7119 return error_mark_node
;
7121 if (issue_conversion_warnings
)
7122 expr
= cp_convert_and_check (totype
, expr
, complain
);
7124 expr
= cp_convert (totype
, expr
, complain
);
7129 /* ARG is being passed to a varargs function. Perform any conversions
7130 required. Return the converted value. */
7133 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7136 location_t loc
= EXPR_LOC_OR_LOC (arg
, input_location
);
7140 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7141 standard conversions are performed. */
7142 arg
= decay_conversion (arg
, complain
);
7143 arg_type
= TREE_TYPE (arg
);
7146 If the argument has integral or enumeration type that is subject
7147 to the integral promotions (_conv.prom_), or a floating point
7148 type that is subject to the floating point promotion
7149 (_conv.fpprom_), the value of the argument is converted to the
7150 promoted type before the call. */
7151 if (TREE_CODE (arg_type
) == REAL_TYPE
7152 && (TYPE_PRECISION (arg_type
)
7153 < TYPE_PRECISION (double_type_node
))
7154 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7156 if ((complain
& tf_warning
)
7157 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7158 warning_at (loc
, OPT_Wdouble_promotion
,
7159 "implicit conversion from %qH to %qI when passing "
7160 "argument to function",
7161 arg_type
, double_type_node
);
7162 arg
= convert_to_real_nofold (double_type_node
, arg
);
7164 else if (NULLPTR_TYPE_P (arg_type
))
7165 arg
= null_pointer_node
;
7166 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7168 if (SCOPED_ENUM_P (arg_type
))
7170 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7172 prom
= cp_perform_integral_promotions (prom
, complain
);
7173 if (abi_version_crosses (6)
7174 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7175 && (complain
& tf_warning
))
7176 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
7177 "%qT before -fabi-version=6, %qT after", arg_type
,
7178 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7179 if (!abi_version_at_least (6))
7183 arg
= cp_perform_integral_promotions (arg
, complain
);
7186 arg
= require_complete_type_sfinae (arg
, complain
);
7187 arg_type
= TREE_TYPE (arg
);
7189 if (arg
!= error_mark_node
7190 /* In a template (or ill-formed code), we can have an incomplete type
7191 even after require_complete_type_sfinae, in which case we don't know
7192 whether it has trivial copy or not. */
7193 && COMPLETE_TYPE_P (arg_type
)
7194 && !cp_unevaluated_operand
)
7196 /* [expr.call] 5.2.2/7:
7197 Passing a potentially-evaluated argument of class type (Clause 9)
7198 with a non-trivial copy constructor or a non-trivial destructor
7199 with no corresponding parameter is conditionally-supported, with
7200 implementation-defined semantics.
7202 We support it as pass-by-invisible-reference, just like a normal
7205 If the call appears in the context of a sizeof expression,
7206 it is not potentially-evaluated. */
7207 if (type_has_nontrivial_copy_init (arg_type
)
7208 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7210 arg
= force_rvalue (arg
, complain
);
7211 if (complain
& tf_warning
)
7212 warning (OPT_Wconditionally_supported
,
7213 "passing objects of non-trivially-copyable "
7214 "type %q#T through %<...%> is conditionally supported",
7216 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7218 /* Build up a real lvalue-to-rvalue conversion in case the
7219 copy constructor is trivial but not callable. */
7220 else if (CLASS_TYPE_P (arg_type
))
7221 force_rvalue (arg
, complain
);
7228 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7231 build_x_va_arg (source_location loc
, tree expr
, tree type
)
7233 if (processing_template_decl
)
7235 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7236 SET_EXPR_LOCATION (r
, loc
);
7240 type
= complete_type_or_else (type
, NULL_TREE
);
7242 if (expr
== error_mark_node
|| !type
)
7243 return error_mark_node
;
7245 expr
= mark_lvalue_use (expr
);
7247 if (TREE_CODE (type
) == REFERENCE_TYPE
)
7249 error ("cannot receive reference type %qT through %<...%>", type
);
7250 return error_mark_node
;
7253 if (type_has_nontrivial_copy_init (type
)
7254 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7256 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7257 it as pass by invisible reference. */
7258 warning_at (loc
, OPT_Wconditionally_supported
,
7259 "receiving objects of non-trivially-copyable type %q#T "
7260 "through %<...%> is conditionally-supported", type
);
7262 tree ref
= cp_build_reference_type (type
, false);
7263 expr
= build_va_arg (loc
, expr
, ref
);
7264 return convert_from_reference (expr
);
7267 tree ret
= build_va_arg (loc
, expr
, type
);
7268 if (CLASS_TYPE_P (type
))
7269 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7270 know how to handle it. */
7271 ret
= get_target_expr (ret
);
7275 /* TYPE has been given to va_arg. Apply the default conversions which
7276 would have happened when passed via ellipsis. Return the promoted
7277 type, or the passed type if there is no change. */
7280 cxx_type_promotes_to (tree type
)
7284 /* Perform the array-to-pointer and function-to-pointer
7286 type
= type_decays_to (type
);
7288 promote
= type_promotes_to (type
);
7289 if (same_type_p (type
, promote
))
7295 /* ARG is a default argument expression being passed to a parameter of
7296 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7297 zero-based argument number. Do any required conversions. Return
7298 the converted value. */
7300 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7302 push_defarg_context (tree fn
)
7303 { vec_safe_push (default_arg_context
, fn
); }
7306 pop_defarg_context (void)
7307 { default_arg_context
->pop (); }
7310 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7311 tsubst_flags_t complain
)
7316 /* See through clones. */
7317 fn
= DECL_ORIGIN (fn
);
7318 /* And inheriting ctors. */
7319 if (flag_new_inheriting_ctors
)
7320 fn
= strip_inheriting_ctors (fn
);
7322 /* Detect recursion. */
7323 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7326 if (complain
& tf_error
)
7327 error ("recursive evaluation of default argument for %q#D", fn
);
7328 return error_mark_node
;
7331 /* If the ARG is an unparsed default argument expression, the
7332 conversion cannot be performed. */
7333 if (TREE_CODE (arg
) == DEFAULT_ARG
)
7335 if (complain
& tf_error
)
7336 error ("call to %qD uses the default argument for parameter %P, which "
7337 "is not yet defined", fn
, parmnum
);
7338 return error_mark_node
;
7341 push_defarg_context (fn
);
7343 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7344 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7350 The names in the expression are bound, and the semantic
7351 constraints are checked, at the point where the default
7352 expressions appears.
7354 we must not perform access checks here. */
7355 push_deferring_access_checks (dk_no_check
);
7356 /* We must make a copy of ARG, in case subsequent processing
7357 alters any part of it. */
7358 arg
= break_out_target_exprs (arg
);
7359 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7360 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7362 arg
= convert_for_arg_passing (type
, arg
, complain
);
7363 pop_deferring_access_checks();
7365 pop_defarg_context ();
7370 /* Returns the type which will really be used for passing an argument of
7374 type_passed_as (tree type
)
7376 /* Pass classes with copy ctors by invisible reference. */
7377 if (TREE_ADDRESSABLE (type
))
7379 type
= build_reference_type (type
);
7380 /* There are no other pointers to this temporary. */
7381 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7383 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7384 && INTEGRAL_TYPE_P (type
)
7385 && COMPLETE_TYPE_P (type
)
7386 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7387 type
= integer_type_node
;
7392 /* Actually perform the appropriate conversion. */
7395 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7399 /* If VAL is a bitfield, then -- since it has already been converted
7400 to TYPE -- it cannot have a precision greater than TYPE.
7402 If it has a smaller precision, we must widen it here. For
7403 example, passing "int f:3;" to a function expecting an "int" will
7404 not result in any conversion before this point.
7406 If the precision is the same we must not risk widening. For
7407 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7408 often have type "int", even though the C++ type for the field is
7409 "long long". If the value is being passed to a function
7410 expecting an "int", then no conversions will be required. But,
7411 if we call convert_bitfield_to_declared_type, the bitfield will
7412 be converted to "long long". */
7413 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7415 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7416 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7418 if (val
== error_mark_node
)
7420 /* Pass classes with copy ctors by invisible reference. */
7421 else if (TREE_ADDRESSABLE (type
))
7422 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7423 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7424 && INTEGRAL_TYPE_P (type
)
7425 && COMPLETE_TYPE_P (type
)
7426 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7427 val
= cp_perform_integral_promotions (val
, complain
);
7428 if (complain
& tf_warning
)
7430 if (warn_suggest_attribute_format
)
7432 tree rhstype
= TREE_TYPE (val
);
7433 const enum tree_code coder
= TREE_CODE (rhstype
);
7434 const enum tree_code codel
= TREE_CODE (type
);
7435 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7437 && check_missing_format_attribute (type
, rhstype
))
7438 warning (OPT_Wsuggest_attribute_format
,
7439 "argument of function call might be a candidate "
7440 "for a format attribute");
7442 maybe_warn_parm_abi (type
, EXPR_LOC_OR_LOC (val
, input_location
));
7447 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7448 which just decay_conversion or no conversions at all should be done.
7449 This is true for some builtins which don't act like normal functions.
7450 Return 2 if no conversions at all should be done, 1 if just
7451 decay_conversion. Return 3 for special treatment of the 3rd argument
7452 for __builtin_*_overflow_p. */
7455 magic_varargs_p (tree fn
)
7457 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7458 switch (DECL_FUNCTION_CODE (fn
))
7460 case BUILT_IN_CLASSIFY_TYPE
:
7461 case BUILT_IN_CONSTANT_P
:
7462 case BUILT_IN_NEXT_ARG
:
7463 case BUILT_IN_VA_START
:
7466 case BUILT_IN_ADD_OVERFLOW_P
:
7467 case BUILT_IN_SUB_OVERFLOW_P
:
7468 case BUILT_IN_MUL_OVERFLOW_P
:
7472 return lookup_attribute ("type generic",
7473 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7479 /* Returns the decl of the dispatcher function if FN is a function version. */
7482 get_function_version_dispatcher (tree fn
)
7484 tree dispatcher_decl
= NULL
;
7486 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7487 && DECL_FUNCTION_VERSIONED (fn
));
7489 gcc_assert (targetm
.get_function_versions_dispatcher
);
7490 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7492 if (dispatcher_decl
== NULL
)
7494 error_at (input_location
, "use of multiversioned function "
7495 "without a default");
7499 retrofit_lang_decl (dispatcher_decl
);
7500 gcc_assert (dispatcher_decl
!= NULL
);
7501 return dispatcher_decl
;
7504 /* fn is a function version dispatcher that is marked used. Mark all the
7505 semantically identical function versions it will dispatch as used. */
7508 mark_versions_used (tree fn
)
7510 struct cgraph_node
*node
;
7511 struct cgraph_function_version_info
*node_v
;
7512 struct cgraph_function_version_info
*it_v
;
7514 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7516 node
= cgraph_node::get (fn
);
7520 gcc_assert (node
->dispatcher_function
);
7522 node_v
= node
->function_version ();
7526 /* All semantically identical versions are chained. Traverse and mark each
7527 one of them as used. */
7528 it_v
= node_v
->next
;
7529 while (it_v
!= NULL
)
7531 mark_used (it_v
->this_node
->decl
);
7536 /* Build a call to "the copy constructor" for the type of A, even if it
7537 wouldn't be selected by normal overload resolution. Used for
7541 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7543 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7544 tree binfo
= TYPE_BINFO (ctype
);
7545 tree copy
= get_copy_ctor (ctype
, complain
);
7546 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7547 tree ob
= build_dummy_object (ctype
);
7548 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7549 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7550 LOOKUP_NORMAL
, NULL
, complain
);
7551 release_tree_vector (args
);
7555 /* Return true iff T refers to a base field. */
7558 is_base_field_ref (tree t
)
7561 if (TREE_CODE (t
) == ADDR_EXPR
)
7562 t
= TREE_OPERAND (t
, 0);
7563 if (TREE_CODE (t
) == COMPONENT_REF
)
7564 t
= TREE_OPERAND (t
, 1);
7565 if (TREE_CODE (t
) == FIELD_DECL
)
7566 return DECL_FIELD_IS_BASE (t
);
7570 /* We can't elide a copy from a function returning by value to a base
7571 subobject, as the callee might clobber tail padding. Return true iff this
7572 could be that case. */
7575 unsafe_copy_elision_p (tree target
, tree exp
)
7577 /* Copy elision only happens with a TARGET_EXPR. */
7578 if (TREE_CODE (exp
) != TARGET_EXPR
)
7580 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7581 /* It's safe to elide the copy for a class with no tail padding. */
7582 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7584 /* It's safe to elide the copy if we aren't initializing a base object. */
7585 if (!is_base_field_ref (target
))
7587 tree init
= TARGET_EXPR_INITIAL (exp
);
7588 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7589 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7590 init
= TREE_OPERAND (init
, 1);
7591 if (TREE_CODE (init
) == COND_EXPR
)
7593 /* We'll end up copying from each of the arms of the COND_EXPR directly
7594 into the target, so look at them. */
7595 if (tree op
= TREE_OPERAND (init
, 1))
7596 if (unsafe_copy_elision_p (target
, op
))
7598 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7600 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7601 && !AGGR_INIT_VIA_CTOR_P (init
));
7604 /* True iff C is a conversion that binds a reference to a prvalue. */
7607 conv_binds_ref_to_prvalue (conversion
*c
)
7609 if (c
->kind
!= ck_ref_bind
)
7611 if (c
->need_temporary_p
)
7614 c
= next_conversion (c
);
7616 if (c
->kind
== ck_rvalue
)
7618 if (c
->kind
== ck_user
&& TREE_CODE (c
->type
) != REFERENCE_TYPE
)
7620 if (c
->kind
== ck_identity
&& c
->u
.expr
7621 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7627 /* Subroutine of the various build_*_call functions. Overload resolution
7628 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7629 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7630 bitmask of various LOOKUP_* flags which apply to the call itself. */
7633 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7636 const vec
<tree
, va_gc
> *args
= cand
->args
;
7637 tree first_arg
= cand
->first_arg
;
7638 conversion
**convs
= cand
->convs
;
7640 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
7645 unsigned int arg_index
= 0;
7649 bool already_used
= false;
7651 /* In a template, there is no need to perform all of the work that
7652 is normally done. We are only interested in the type of the call
7653 expression, i.e., the return type of the function. Any semantic
7654 errors will be deferred until the template is instantiated. */
7655 if (processing_template_decl
)
7659 const tree
*argarray
;
7662 if (undeduced_auto_decl (fn
))
7663 mark_used (fn
, complain
);
7665 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
7669 return_type
= TREE_TYPE (TREE_TYPE (fn
));
7670 nargs
= vec_safe_length (args
);
7671 if (first_arg
== NULL_TREE
)
7672 argarray
= args
->address ();
7680 alcarray
= XALLOCAVEC (tree
, nargs
);
7681 alcarray
[0] = build_this (first_arg
);
7682 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
7683 alcarray
[ix
+ 1] = arg
;
7684 argarray
= alcarray
;
7687 addr
= build_addr_func (fn
, complain
);
7688 if (addr
== error_mark_node
)
7689 return error_mark_node
;
7690 expr
= build_call_array_loc (input_location
, return_type
,
7691 addr
, nargs
, argarray
);
7692 if (TREE_THIS_VOLATILE (fn
) && cfun
)
7693 current_function_returns_abnormally
= 1;
7694 return convert_from_reference (expr
);
7697 /* Give any warnings we noticed during overload resolution. */
7698 if (cand
->warnings
&& (complain
& tf_warning
))
7700 struct candidate_warning
*w
;
7701 for (w
= cand
->warnings
; w
; w
= w
->next
)
7702 joust (cand
, w
->loser
, 1, complain
);
7705 /* Core issue 2327: P0135 doesn't say how to handle the case where the
7706 argument to the copy constructor ends up being a prvalue after
7707 conversion. Let's do the normal processing, but pretend we aren't
7708 actually using the copy constructor. */
7709 bool force_elide
= false;
7710 if (cxx_dialect
>= cxx17
7711 && cand
->num_convs
== 1
7712 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
7713 && (DECL_COPY_CONSTRUCTOR_P (fn
)
7714 || DECL_MOVE_CONSTRUCTOR_P (fn
))
7715 && conv_binds_ref_to_prvalue (convs
[0]))
7718 goto not_really_used
;
7721 /* OK, we're actually calling this inherited constructor; set its deletedness
7722 appropriately. We can get away with doing this here because calling is
7723 the only way to refer to a constructor. */
7724 if (DECL_INHERITED_CTOR (fn
))
7725 deduce_inheriting_ctor (fn
);
7727 /* Make =delete work with SFINAE. */
7728 if (DECL_DELETED_FN (fn
))
7730 if (complain
& tf_error
)
7732 return error_mark_node
;
7735 if (DECL_FUNCTION_MEMBER_P (fn
))
7738 /* If FN is a template function, two cases must be considered.
7743 template <class T> void f();
7745 template <class T> struct B {
7749 struct C : A, B<int> {
7751 using B<int>::g; // #2
7754 In case #1 where `A::f' is a member template, DECL_ACCESS is
7755 recorded in the primary template but not in its specialization.
7756 We check access of FN using its primary template.
7758 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7759 because it is a member of class template B, DECL_ACCESS is
7760 recorded in the specialization `B<int>::g'. We cannot use its
7761 primary template because `B<T>::g' and `B<int>::g' may have
7762 different access. */
7763 if (DECL_TEMPLATE_INFO (fn
)
7764 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
7765 access_fn
= DECL_TI_TEMPLATE (fn
);
7768 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
7770 return error_mark_node
;
7773 /* If we're checking for implicit delete, don't bother with argument
7775 if (flags
& LOOKUP_SPECULATIVE
)
7777 if (cand
->viable
== 1)
7779 else if (!(complain
& tf_error
))
7780 /* Reject bad conversions now. */
7781 return error_mark_node
;
7782 /* else continue to get conversion error. */
7787 /* N3276 magic doesn't apply to nested calls. */
7788 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
7789 complain
&= ~tf_decltype
;
7790 /* No-Cleanup doesn't apply to nested calls either. */
7791 tsubst_flags_t no_cleanup_complain
= complain
;
7792 complain
&= ~tf_no_cleanup
;
7794 /* Find maximum size of vector to hold converted arguments. */
7795 parmlen
= list_length (parm
);
7796 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
7797 if (parmlen
> nargs
)
7799 argarray
= XALLOCAVEC (tree
, nargs
);
7801 /* The implicit parameters to a constructor are not considered by overload
7802 resolution, and must be of the proper type. */
7803 if (DECL_CONSTRUCTOR_P (fn
))
7806 if (first_arg
!= NULL_TREE
)
7808 object_arg
= first_arg
;
7809 first_arg
= NULL_TREE
;
7813 object_arg
= (*args
)[arg_index
];
7816 argarray
[j
++] = build_this (object_arg
);
7817 parm
= TREE_CHAIN (parm
);
7818 /* We should never try to call the abstract constructor. */
7819 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
7821 if (DECL_HAS_VTT_PARM_P (fn
))
7823 argarray
[j
++] = (*args
)[arg_index
];
7825 parm
= TREE_CHAIN (parm
);
7828 if (flags
& LOOKUP_PREFER_RVALUE
)
7830 /* The implicit move specified in 15.8.3/3 fails "...if the type of
7831 the first parameter of the selected constructor is not an rvalue
7832 reference to the object’s type (possibly cv-qualified)...." */
7833 gcc_assert (!(complain
& tf_error
));
7834 tree ptype
= convs
[0]->type
;
7835 if (TREE_CODE (ptype
) != REFERENCE_TYPE
7836 || !TYPE_REF_IS_RVALUE (ptype
)
7837 || CONVERSION_RANK (convs
[0]) > cr_exact
)
7838 return error_mark_node
;
7841 /* Bypass access control for 'this' parameter. */
7842 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
7844 tree parmtype
= TREE_VALUE (parm
);
7845 tree arg
= build_this (first_arg
!= NULL_TREE
7847 : (*args
)[arg_index
]);
7848 tree argtype
= TREE_TYPE (arg
);
7852 if (arg
== error_mark_node
)
7853 return error_mark_node
;
7855 if (convs
[i
]->bad_p
)
7857 if (complain
& tf_error
)
7859 if (permerror (input_location
, "passing %qT as %<this%> "
7860 "argument discards qualifiers",
7861 TREE_TYPE (argtype
)))
7862 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
7865 return error_mark_node
;
7868 /* See if the function member or the whole class type is declared
7869 final and the call can be devirtualized. */
7870 if (DECL_FINAL_P (fn
)
7871 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
7872 flags
|= LOOKUP_NONVIRTUAL
;
7874 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
7875 X is called for an object that is not of type X, or of a type
7876 derived from X, the behavior is undefined.
7878 So we can assume that anything passed as 'this' is non-null, and
7879 optimize accordingly. */
7880 gcc_assert (TYPE_PTR_P (parmtype
));
7881 /* Convert to the base in which the function was declared. */
7882 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
7883 converted_arg
= build_base_path (PLUS_EXPR
,
7885 cand
->conversion_path
,
7887 /* Check that the base class is accessible. */
7888 if (!accessible_base_p (TREE_TYPE (argtype
),
7889 BINFO_TYPE (cand
->conversion_path
), true))
7891 if (complain
& tf_error
)
7892 error ("%qT is not an accessible base of %qT",
7893 BINFO_TYPE (cand
->conversion_path
),
7894 TREE_TYPE (argtype
));
7896 return error_mark_node
;
7898 /* If fn was found by a using declaration, the conversion path
7899 will be to the derived class, not the base declaring fn. We
7900 must convert from derived to base. */
7901 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
7902 TREE_TYPE (parmtype
), ba_unique
,
7904 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
7905 base_binfo
, 1, complain
);
7907 argarray
[j
++] = converted_arg
;
7908 parm
= TREE_CHAIN (parm
);
7909 if (first_arg
!= NULL_TREE
)
7910 first_arg
= NULL_TREE
;
7917 gcc_assert (first_arg
== NULL_TREE
);
7918 for (; arg_index
< vec_safe_length (args
) && parm
;
7919 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
7921 tree type
= TREE_VALUE (parm
);
7922 tree arg
= (*args
)[arg_index
];
7923 bool conversion_warning
= true;
7927 /* If the argument is NULL and used to (implicitly) instantiate a
7928 template function (and bind one of the template arguments to
7929 the type of 'long int'), we don't want to warn about passing NULL
7930 to non-pointer argument.
7931 For example, if we have this template function:
7933 template<typename T> void func(T x) {}
7935 we want to warn (when -Wconversion is enabled) in this case:
7941 but not in this case:
7947 if (null_node_p (arg
)
7948 && DECL_TEMPLATE_INFO (fn
)
7949 && cand
->template_decl
7950 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
7951 conversion_warning
= false;
7953 /* Warn about initializer_list deduction that isn't currently in the
7955 if (cxx_dialect
> cxx98
7956 && flag_deduce_init_list
7957 && cand
->template_decl
7958 && is_std_init_list (non_reference (type
))
7959 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
7961 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
7962 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
7963 tree patparm
= get_pattern_parm (realparm
, tmpl
);
7964 tree pattype
= TREE_TYPE (patparm
);
7965 if (PACK_EXPANSION_P (pattype
))
7966 pattype
= PACK_EXPANSION_PATTERN (pattype
);
7967 pattype
= non_reference (pattype
);
7969 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
7970 && (cand
->explicit_targs
== NULL_TREE
7971 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
7972 <= TEMPLATE_TYPE_IDX (pattype
))))
7974 pedwarn (input_location
, 0, "deducing %qT as %qT",
7975 non_reference (TREE_TYPE (patparm
)),
7976 non_reference (type
));
7977 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
7978 " in call to %qD", cand
->fn
);
7979 pedwarn (input_location
, 0,
7980 " (you can disable this with -fno-deduce-init-list)");
7984 /* Set user_conv_p on the argument conversions, so rvalue/base handling
7985 knows not to allow any more UDCs. This needs to happen after we
7986 process cand->warnings. */
7987 if (flags
& LOOKUP_NO_CONVERSION
)
7988 conv
->user_conv_p
= true;
7990 tsubst_flags_t arg_complain
= complain
;
7991 if (!conversion_warning
)
7992 arg_complain
&= ~tf_warning
;
7994 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
7996 val
= convert_for_arg_passing (type
, val
, arg_complain
);
7998 if (val
== error_mark_node
)
7999 return error_mark_node
;
8001 argarray
[j
++] = val
;
8004 /* Default arguments */
8005 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8007 if (TREE_VALUE (parm
) == error_mark_node
)
8008 return error_mark_node
;
8009 val
= convert_default_arg (TREE_VALUE (parm
),
8010 TREE_PURPOSE (parm
),
8013 if (val
== error_mark_node
)
8014 return error_mark_node
;
8015 argarray
[j
++] = val
;
8019 int magic
= magic_varargs_p (fn
);
8020 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8022 tree a
= (*args
)[arg_index
];
8023 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8025 /* Do no conversions for certain magic varargs. */
8026 a
= mark_type_use (a
);
8027 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8028 return error_mark_node
;
8030 else if (magic
!= 0)
8031 /* For other magic varargs only do decay_conversion. */
8032 a
= decay_conversion (a
, complain
);
8033 else if (DECL_CONSTRUCTOR_P (fn
)
8034 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8037 /* Avoid infinite recursion trying to call A(...). */
8038 if (complain
& tf_error
)
8039 /* Try to call the actual copy constructor for a good error. */
8040 call_copy_ctor (a
, complain
);
8041 return error_mark_node
;
8044 a
= convert_arg_to_ellipsis (a
, complain
);
8045 if (a
== error_mark_node
)
8046 return error_mark_node
;
8050 gcc_assert (j
<= nargs
);
8053 /* Avoid to do argument-transformation, if warnings for format, and for
8054 nonnull are disabled. Just in case that at least one of them is active
8055 the check_function_arguments function might warn about something. */
8057 bool warned_p
= false;
8060 || warn_suggest_attribute_format
8063 tree
*fargs
= (!nargs
? argarray
8064 : (tree
*) alloca (nargs
* sizeof (tree
)));
8065 for (j
= 0; j
< nargs
; j
++)
8067 /* For -Wformat undo the implicit passing by hidden reference
8068 done by convert_arg_to_ellipsis. */
8069 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8070 && TREE_CODE (TREE_TYPE (argarray
[j
])) == REFERENCE_TYPE
)
8071 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8073 fargs
[j
] = maybe_constant_value (argarray
[j
]);
8076 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8077 nargs
, fargs
, NULL
);
8080 if (DECL_INHERITED_CTOR (fn
))
8082 /* Check for passing ellipsis arguments to an inherited constructor. We
8083 could handle this by open-coding the inherited constructor rather than
8084 defining it, but let's not bother now. */
8085 if (!cp_unevaluated_operand
8087 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8089 if (complain
& tf_error
)
8091 sorry ("passing arguments to ellipsis of inherited constructor "
8093 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8095 return error_mark_node
;
8098 /* A base constructor inheriting from a virtual base doesn't get the
8099 inherited arguments, just this and __vtt. */
8100 if (ctor_omit_inherited_parms (fn
))
8104 /* Avoid actually calling copy constructors and copy assignment operators,
8107 if (! flag_elide_constructors
&& !force_elide
)
8108 /* Do things the hard way. */;
8109 else if (cand
->num_convs
== 1
8110 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8111 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8112 /* It's unsafe to elide the constructor when handling
8113 a noexcept-expression, it may evaluate to the wrong
8114 value (c++/53025). */
8115 && (force_elide
|| cp_noexcept_operand
== 0))
8118 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8120 bool trivial
= trivial_fn_p (fn
);
8122 /* Pull out the real argument, disregarding const-correctness. */
8124 /* Strip the reference binding for the constructor parameter. */
8125 if (CONVERT_EXPR_P (targ
)
8126 && TREE_CODE (TREE_TYPE (targ
)) == REFERENCE_TYPE
)
8127 targ
= TREE_OPERAND (targ
, 0);
8128 /* But don't strip any other reference bindings; binding a temporary to a
8129 reference prevents copy elision. */
8130 while ((CONVERT_EXPR_P (targ
)
8131 && TREE_CODE (TREE_TYPE (targ
)) != REFERENCE_TYPE
)
8132 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8133 targ
= TREE_OPERAND (targ
, 0);
8134 if (TREE_CODE (targ
) == ADDR_EXPR
)
8136 targ
= TREE_OPERAND (targ
, 0);
8137 if (!same_type_ignoring_top_level_qualifiers_p
8138 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8147 arg
= cp_build_fold_indirect_ref (arg
);
8149 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8151 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8152 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8154 /* It's from binding the ref parm to a packed field. */
8155 || convs
[0]->need_temporary_p
8157 /* See unsafe_copy_elision_p. */
8158 || DECL_BASE_CONSTRUCTOR_P (fn
));
8160 /* [class.copy]: the copy constructor is implicitly defined even if
8161 the implementation elided its use. */
8162 if (!trivial
&& !force_elide
)
8164 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8165 return error_mark_node
;
8166 already_used
= true;
8169 /* If we're creating a temp and we already have one, don't create a
8170 new one. If we're not creating a temp but we get one, use
8171 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8172 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8173 temp or an INIT_EXPR otherwise. */
8175 if (is_dummy_object (fa
))
8177 if (TREE_CODE (arg
) == TARGET_EXPR
)
8180 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8182 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8183 && !unsafe_copy_elision_p (fa
, arg
))
8185 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8187 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8191 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8192 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8193 && trivial_fn_p (fn
))
8195 tree to
= cp_stabilize_reference
8196 (cp_build_fold_indirect_ref (argarray
[0]));
8197 tree type
= TREE_TYPE (to
);
8198 tree as_base
= CLASSTYPE_AS_BASE (type
);
8199 tree arg
= argarray
[1];
8201 if (is_really_empty_class (type
))
8203 /* Avoid copying empty classes. */
8204 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8205 TREE_NO_WARNING (val
) = 1;
8207 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8209 arg
= cp_build_fold_indirect_ref (arg
);
8210 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8214 /* We must only copy the non-tail padding parts. */
8216 tree array_type
, alias_set
;
8218 arg2
= TYPE_SIZE_UNIT (as_base
);
8219 arg0
= cp_build_addr_expr (to
, complain
);
8221 array_type
= build_array_type (unsigned_char_type_node
,
8223 (size_binop (MINUS_EXPR
,
8224 arg2
, size_int (1))));
8225 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8226 t
= build2 (MODIFY_EXPR
, void_type_node
,
8227 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8228 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8229 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8230 TREE_NO_WARNING (val
) = 1;
8235 else if (trivial_fn_p (fn
))
8237 if (DECL_DESTRUCTOR_P (fn
))
8238 return fold_convert (void_type_node
, argarray
[0]);
8239 else if (default_ctor_p (fn
))
8241 if (is_dummy_object (argarray
[0]))
8242 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8243 no_cleanup_complain
);
8245 return cp_build_fold_indirect_ref (argarray
[0]);
8249 gcc_assert (!force_elide
);
8252 && !mark_used (fn
, complain
))
8253 return error_mark_node
;
8255 /* Warn if the built-in writes to an object of a non-trivial type. */
8256 if (warn_class_memaccess
8257 && vec_safe_length (args
) >= 2
8258 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8259 maybe_warn_class_memaccess (input_location
, fn
, args
);
8261 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0
8262 /* Don't mess with virtual lookup in instantiate_non_dependent_expr;
8263 virtual functions can't be constexpr. */
8264 && !in_template_function ())
8267 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8269 ba_any
, NULL
, complain
);
8270 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8272 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8274 if (TREE_SIDE_EFFECTS (argarray
[0]))
8275 argarray
[0] = save_expr (argarray
[0]);
8276 t
= build_pointer_type (TREE_TYPE (fn
));
8277 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8282 fn
= build_addr_func (fn
, complain
);
8283 if (fn
== error_mark_node
)
8284 return error_mark_node
;
8287 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8288 if (call
== error_mark_node
)
8290 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8292 tree c
= extract_call_expr (call
);
8293 /* build_new_op_1 will clear this when appropriate. */
8294 CALL_EXPR_ORDERED_ARGS (c
) = true;
8298 tree c
= extract_call_expr (call
);
8299 if (TREE_CODE (c
) == CALL_EXPR
)
8300 TREE_NO_WARNING (c
) = 1;
8308 /* Return the DECL of the first non-static subobject of class TYPE
8309 that satisfies the predicate PRED or null if none can be found. */
8311 template <class Predicate
>
8313 first_non_static_field (tree type
, Predicate pred
)
8315 if (!type
|| !CLASS_TYPE_P (type
))
8318 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8320 if (TREE_CODE (field
) != FIELD_DECL
)
8322 if (TREE_STATIC (field
))
8330 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8331 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8333 tree base
= TREE_TYPE (base_binfo
);
8336 if (tree field
= first_non_static_field (base
, pred
))
8343 struct NonPublicField
8345 bool operator() (const_tree t
)
8347 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8351 /* Return the DECL of the first non-public subobject of class TYPE
8352 or null if none can be found. */
8355 first_non_public_field (tree type
)
8357 return first_non_static_field (type
, NonPublicField ());
8360 struct NonTrivialField
8362 bool operator() (const_tree t
)
8364 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8368 /* Return the DECL of the first non-trivial subobject of class TYPE
8369 or null if none can be found. */
8372 first_non_trivial_field (tree type
)
8374 return first_non_static_field (type
, NonTrivialField ());
8377 } /* unnamed namespace */
8379 /* Return true if all copy and move assignment operator overloads for
8380 class TYPE are trivial and at least one of them is not deleted and,
8381 when ACCESS is set, accessible. Return false otherwise. Set
8382 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8383 copy or move assignment. */
8386 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8388 tree fns
= get_class_binding (type
, assign_op_identifier
);
8389 bool all_trivial
= true;
8391 /* Iterate over overloads of the assignment operator, checking
8392 accessible copy assignments for triviality. */
8394 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8398 /* Skip operators that aren't copy assignments. */
8402 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8403 || accessible_p (TYPE_BINFO (type
), f
, true));
8405 /* Skip template assignment operators and deleted functions. */
8406 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8412 if (!accessible
|| !trivial_fn_p (f
))
8413 all_trivial
= false;
8415 /* Break early when both properties have been determined. */
8416 if (*hasassign
&& !all_trivial
)
8420 /* Return true if they're all trivial and one of the expressions
8421 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8422 tree ref
= cp_build_reference_type (type
, false);
8424 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8425 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8428 /* Return true if all copy and move ctor overloads for class TYPE are
8429 trivial and at least one of them is not deleted and, when ACCESS is
8430 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8431 to true when the TYPE has a (not necessarily trivial) default and copy
8432 (or move) ctor, respectively. */
8435 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8437 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8438 bool all_trivial
= true;
8440 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8444 /* Skip template constructors. */
8445 if (TREE_CODE (f
) != FUNCTION_DECL
)
8448 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8450 /* Skip ctors other than default, copy, and move. */
8451 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8454 if (DECL_DELETED_FN (f
))
8457 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8458 || accessible_p (TYPE_BINFO (type
), f
, true));
8461 hasctor
[cpy_or_move_ctor_p
] = true;
8463 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8464 all_trivial
= false;
8466 /* Break early when both properties have been determined. */
8467 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8474 /* Issue a warning on a call to the built-in function FNDECL if it is
8475 a raw memory write whose destination is not an object of (something
8476 like) trivial or standard layout type with a non-deleted assignment
8477 and copy ctor. Detects const correctness violations, corrupting
8478 references, virtual table pointers, and bypassing non-trivial
8482 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8483 const vec
<tree
, va_gc
> *args
)
8485 /* Except for bcopy where it's second, the destination pointer is
8486 the first argument for all functions handled here. Compute
8487 the index of the destination and source arguments. */
8488 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8489 unsigned srcidx
= !dstidx
;
8491 tree dest
= (*args
)[dstidx
];
8492 if (!TREE_TYPE (dest
) || !POINTER_TYPE_P (TREE_TYPE (dest
)))
8495 tree srctype
= NULL_TREE
;
8497 /* Determine the type of the pointed-to object and whether it's
8498 a complete class type. */
8499 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8501 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8504 /* Check to see if the raw memory call is made by a non-static member
8505 function with THIS as the destination argument for the destination
8506 type. If so, and if the class has no non-trivial bases or members,
8507 be more permissive. */
8508 if (current_function_decl
8509 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8510 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8512 tree ctx
= DECL_CONTEXT (current_function_decl
);
8513 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8514 tree binfo
= TYPE_BINFO (ctx
);
8516 /* FIXME: The following if statement is overly permissive (see
8517 bug 84851). Remove it in GCC 9. */
8519 && !BINFO_VTABLE (binfo
)
8520 && !BINFO_N_BASE_BINFOS (binfo
)
8521 && (DECL_CONSTRUCTOR_P (current_function_decl
)
8522 || DECL_DESTRUCTOR_P (current_function_decl
)))
8526 && !BINFO_VTABLE (binfo
)
8527 && !first_non_trivial_field (desttype
))
8531 /* True if the class is trivial. */
8532 bool trivial
= trivial_type_p (desttype
);
8534 /* Set to true if DESTYPE has an accessible copy assignment. */
8535 bool hasassign
= false;
8536 /* True if all of the class' overloaded copy assignment operators
8537 are all trivial (and not deleted) and at least one of them is
8539 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8541 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8543 bool hasctors
[2] = { false, false };
8545 /* True if all of the class' overloaded copy constructors are all
8546 trivial (and not deleted) and at least one of them is accessible. */
8547 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8549 /* Set FLD to the first private/protected member of the class. */
8550 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8552 /* The warning format string. */
8553 const char *warnfmt
= NULL
;
8554 /* A suggested alternative to offer instead of the raw memory call.
8555 Empty string when none can be come up with. */
8556 const char *suggest
= "";
8557 bool warned
= false;
8559 switch (DECL_FUNCTION_CODE (fndecl
))
8561 case BUILT_IN_MEMSET
:
8562 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8564 /* Diagnose setting non-copy-assignable or non-trivial types,
8565 or types with a private member, to (potentially) non-zero
8566 bytes. Since the value of the bytes being written is unknown,
8567 suggest using assignment instead (if one exists). Also warn
8568 for writes into objects for which zero-initialization doesn't
8569 mean all bits clear (pointer-to-member data, where null is all
8570 bits set). Since the value being written is (most likely)
8571 non-zero, simply suggest assignment (but not copy assignment). */
8572 suggest
= "; use assignment instead";
8574 warnfmt
= G_("%qD writing to an object of type %#qT with "
8575 "no trivial copy-assignment");
8577 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8580 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8581 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8582 "%qD writing to an object of type %#qT with "
8584 fndecl
, desttype
, access
, fld
);
8586 else if (!zero_init_p (desttype
))
8587 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8588 "a pointer to data member%s");
8594 case BUILT_IN_BZERO
:
8595 /* Similarly to the above, diagnose clearing non-trivial or non-
8596 standard layout objects, or objects of types with no assignmenmt.
8597 Since the value being written is known to be zero, suggest either
8598 copy assignment, copy ctor, or default ctor as an alternative,
8599 depending on what's available. */
8601 if (hasassign
&& hasctors
[0])
8602 suggest
= G_("; use assignment or value-initialization instead");
8604 suggest
= G_("; use assignment instead");
8605 else if (hasctors
[0])
8606 suggest
= G_("; use value-initialization instead");
8609 warnfmt
= G_("%qD clearing an object of type %#qT with "
8610 "no trivial copy-assignment%s");
8612 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8613 else if (!zero_init_p (desttype
))
8614 warnfmt
= G_("%qD clearing an object of type %#qT containing "
8615 "a pointer-to-member%s");
8618 case BUILT_IN_BCOPY
:
8619 case BUILT_IN_MEMCPY
:
8620 case BUILT_IN_MEMMOVE
:
8621 case BUILT_IN_MEMPCPY
:
8622 /* Determine the type of the source object. */
8623 srctype
= TREE_TYPE ((*args
)[srcidx
]);
8624 if (!srctype
|| !POINTER_TYPE_P (srctype
))
8625 srctype
= void_type_node
;
8627 srctype
= TREE_TYPE (srctype
);
8629 /* Since it's impossible to determine wheter the byte copy is
8630 being used in place of assignment to an existing object or
8631 as a substitute for initialization, assume it's the former.
8632 Determine the best alternative to use instead depending on
8633 what's not deleted. */
8634 if (hasassign
&& hasctors
[1])
8635 suggest
= G_("; use copy-assignment or copy-initialization instead");
8637 suggest
= G_("; use copy-assignment instead");
8638 else if (hasctors
[1])
8639 suggest
= G_("; use copy-initialization instead");
8642 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
8643 "copy-assignment%s");
8644 else if (!trivially_copyable_p (desttype
))
8645 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
8648 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
8651 && !VOID_TYPE_P (srctype
)
8652 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8653 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8656 /* Warn when copying into a non-trivial object from an object
8657 of a different type other than void or char. */
8658 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8659 "%qD copying an object of non-trivial type "
8660 "%#qT from an array of %#qT",
8661 fndecl
, desttype
, srctype
);
8664 && !VOID_TYPE_P (srctype
)
8665 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8666 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8669 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8670 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8671 "%qD copying an object of type %#qT with "
8672 "%qs member %qD from an array of %#qT; use "
8673 "assignment or copy-initialization instead",
8674 fndecl
, desttype
, access
, fld
, srctype
);
8676 else if (!trivial
&& vec_safe_length (args
) > 2)
8678 tree sz
= maybe_constant_value ((*args
)[2]);
8679 if (!tree_fits_uhwi_p (sz
))
8682 /* Finally, warn on partial copies. */
8683 unsigned HOST_WIDE_INT typesize
8684 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
8685 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
8686 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8687 (typesize
- partial
> 1
8688 ? G_("%qD writing to an object of "
8689 "a non-trivial type %#qT leaves %wu "
8691 : G_("%qD writing to an object of "
8692 "a non-trivial type %#qT leaves %wu "
8694 fndecl
, desttype
, typesize
- partial
);
8698 case BUILT_IN_REALLOC
:
8700 if (!trivially_copyable_p (desttype
))
8701 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
8702 "%#qT; use %<new%> and %<delete%> instead");
8704 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
8705 "constructor; use %<new%> and %<delete%> instead");
8706 else if (!get_dtor (desttype
, tf_none
))
8707 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
8711 tree sz
= maybe_constant_value ((*args
)[1]);
8712 if (TREE_CODE (sz
) == INTEGER_CST
8713 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
8714 /* Finally, warn on reallocation into insufficient space. */
8715 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8716 "%qD moving an object of non-trivial type "
8717 "%#qT and size %E into a region of size %E",
8718 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
8730 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8731 warnfmt
, fndecl
, desttype
, suggest
);
8733 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8734 warnfmt
, fndecl
, desttype
);
8738 inform (location_of (desttype
), "%#qT declared here", desttype
);
8741 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
8742 This function performs no overload resolution, conversion, or other
8743 high-level operations. */
8746 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
8747 tsubst_flags_t complain
)
8751 /* Remember roughly where this call is. */
8752 location_t loc
= EXPR_LOC_OR_LOC (fn
, input_location
);
8753 fn
= build_call_a (fn
, nargs
, argarray
);
8754 SET_EXPR_LOCATION (fn
, loc
);
8756 fndecl
= get_callee_fndecl (fn
);
8758 /* Check that arguments to builtin functions match the expectations. */
8760 && DECL_BUILT_IN (fndecl
)
8761 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
8765 /* We need to take care that values to BUILT_IN_NORMAL
8767 for (i
= 0; i
< nargs
; i
++)
8768 argarray
[i
] = fold_non_dependent_expr (argarray
[i
]);
8770 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
8772 return error_mark_node
;
8775 if (VOID_TYPE_P (TREE_TYPE (fn
)))
8778 /* 5.2.2/11: If a function call is a prvalue of object type: if the
8779 function call is either the operand of a decltype-specifier or the
8780 right operand of a comma operator that is the operand of a
8781 decltype-specifier, a temporary object is not introduced for the
8782 prvalue. The type of the prvalue may be incomplete. */
8783 if (!(complain
& tf_decltype
))
8785 fn
= require_complete_type_sfinae (fn
, complain
);
8786 if (fn
== error_mark_node
)
8787 return error_mark_node
;
8789 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
8791 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
8792 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
8795 return convert_from_reference (fn
);
8798 /* Returns the value to use for the in-charge parameter when making a
8799 call to a function with the indicated NAME.
8801 FIXME:Can't we find a neater way to do this mapping? */
8804 in_charge_arg_for_name (tree name
)
8806 if (IDENTIFIER_CTOR_P (name
))
8808 if (name
== complete_ctor_identifier
)
8809 return integer_one_node
;
8810 gcc_checking_assert (name
== base_ctor_identifier
);
8814 if (name
== complete_dtor_identifier
)
8815 return integer_two_node
;
8816 else if (name
== deleting_dtor_identifier
)
8817 return integer_three_node
;
8818 gcc_checking_assert (name
== base_dtor_identifier
);
8821 return integer_zero_node
;
8824 /* We've built up a constructor call RET. Complain if it delegates to the
8825 constructor we're currently compiling. */
8828 check_self_delegation (tree ret
)
8830 if (TREE_CODE (ret
) == TARGET_EXPR
)
8831 ret
= TARGET_EXPR_INITIAL (ret
);
8832 tree fn
= cp_get_callee_fndecl_nofold (ret
);
8833 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
8834 error ("constructor delegates to itself");
8837 /* Build a call to a constructor, destructor, or an assignment
8838 operator for INSTANCE, an expression with class type. NAME
8839 indicates the special member function to call; *ARGS are the
8840 arguments. ARGS may be NULL. This may change ARGS. BINFO
8841 indicates the base of INSTANCE that is to be passed as the `this'
8842 parameter to the member function called.
8844 FLAGS are the LOOKUP_* flags to use when processing the call.
8846 If NAME indicates a complete object constructor, INSTANCE may be
8847 NULL_TREE. In this case, the caller will call build_cplus_new to
8848 store the newly constructed object into a VAR_DECL. */
8851 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
8852 tree binfo
, int flags
, tsubst_flags_t complain
)
8855 /* The type of the subobject to be constructed or destroyed. */
8857 vec
<tree
, va_gc
> *allocated
= NULL
;
8860 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
8863 /* Resolve the name. */
8864 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
8865 return error_mark_node
;
8867 binfo
= TYPE_BINFO (binfo
);
8870 gcc_assert (binfo
!= NULL_TREE
);
8872 class_type
= BINFO_TYPE (binfo
);
8874 /* Handle the special case where INSTANCE is NULL_TREE. */
8875 if (name
== complete_ctor_identifier
&& !instance
)
8876 instance
= build_dummy_object (class_type
);
8879 if (IDENTIFIER_DTOR_P (name
))
8880 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
8882 /* Convert to the base class, if necessary. */
8883 if (!same_type_ignoring_top_level_qualifiers_p
8884 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
8886 if (IDENTIFIER_CDTOR_P (name
))
8887 /* For constructors and destructors, either the base is
8888 non-virtual, or it is virtual but we are doing the
8889 conversion from a constructor or destructor for the
8890 complete object. In either case, we can convert
8892 instance
= convert_to_base_statically (instance
, binfo
);
8895 /* However, for assignment operators, we must convert
8896 dynamically if the base is virtual. */
8897 gcc_checking_assert (name
== assign_op_identifier
);
8898 instance
= build_base_path (PLUS_EXPR
, instance
,
8899 binfo
, /*nonnull=*/1, complain
);
8904 gcc_assert (instance
!= NULL_TREE
);
8906 /* In C++17, "If the initializer expression is a prvalue and the
8907 cv-unqualified version of the source type is the same class as the class
8908 of the destination, the initializer expression is used to initialize the
8909 destination object." Handle that here to avoid doing overload
8911 if (cxx_dialect
>= cxx17
8912 && args
&& vec_safe_length (*args
) == 1
8913 && name
== complete_ctor_identifier
)
8915 tree arg
= (**args
)[0];
8917 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
8918 && !TYPE_HAS_LIST_CTOR (class_type
)
8919 && CONSTRUCTOR_NELTS (arg
) == 1)
8920 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
8922 if ((TREE_CODE (arg
) == TARGET_EXPR
8923 || TREE_CODE (arg
) == CONSTRUCTOR
)
8924 && (same_type_ignoring_top_level_qualifiers_p
8925 (class_type
, TREE_TYPE (arg
))))
8927 if (is_dummy_object (instance
))
8929 else if (TREE_CODE (arg
) == TARGET_EXPR
)
8930 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
8932 if ((complain
& tf_error
)
8933 && (flags
& LOOKUP_DELEGATING_CONS
))
8934 check_self_delegation (arg
);
8935 /* Avoid change of behavior on Wunused-var-2.C. */
8936 instance
= mark_lvalue_use (instance
);
8937 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
8941 fns
= lookup_fnfields (binfo
, name
, 1);
8943 /* When making a call to a constructor or destructor for a subobject
8944 that uses virtual base classes, pass down a pointer to a VTT for
8946 if ((name
== base_ctor_identifier
8947 || name
== base_dtor_identifier
)
8948 && CLASSTYPE_VBASECLASSES (class_type
))
8953 /* If the current function is a complete object constructor
8954 or destructor, then we fetch the VTT directly.
8955 Otherwise, we look it up using the VTT we were given. */
8956 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
8957 vtt
= decay_conversion (vtt
, complain
);
8958 if (vtt
== error_mark_node
)
8959 return error_mark_node
;
8960 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
8961 if (BINFO_SUBVTT_INDEX (binfo
))
8962 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
8968 allocated
= make_tree_vector ();
8972 vec_safe_insert (*args
, 0, sub_vtt
);
8975 ret
= build_new_method_call (instance
, fns
, args
,
8976 TYPE_BINFO (BINFO_TYPE (binfo
)),
8980 if (allocated
!= NULL
)
8981 release_tree_vector (allocated
);
8983 if ((complain
& tf_error
)
8984 && (flags
& LOOKUP_DELEGATING_CONS
)
8985 && name
== complete_ctor_identifier
)
8986 check_self_delegation (ret
);
8991 /* Return the NAME, as a C string. The NAME indicates a function that
8992 is a member of TYPE. *FREE_P is set to true if the caller must
8993 free the memory returned.
8995 Rather than go through all of this, we should simply set the names
8996 of constructors and destructors appropriately, and dispense with
8997 ctor_identifier, dtor_identifier, etc. */
9000 name_as_c_string (tree name
, tree type
, bool *free_p
)
9002 const char *pretty_name
;
9004 /* Assume that we will not allocate memory. */
9006 /* Constructors and destructors are special. */
9007 if (IDENTIFIER_CDTOR_P (name
))
9010 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9011 /* For a destructor, add the '~'. */
9012 if (IDENTIFIER_DTOR_P (name
))
9014 pretty_name
= concat ("~", pretty_name
, NULL
);
9015 /* Remember that we need to free the memory allocated. */
9019 else if (IDENTIFIER_CONV_OP_P (name
))
9021 pretty_name
= concat ("operator ",
9022 type_as_string_translate (TREE_TYPE (name
),
9023 TFF_PLAIN_IDENTIFIER
),
9025 /* Remember that we need to free the memory allocated. */
9029 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9031 return CONST_CAST (char *, pretty_name
);
9034 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9035 be set, upon return, to the function called. ARGS may be NULL.
9036 This may change ARGS. */
9039 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9040 tree conversion_path
, int flags
,
9041 tree
*fn_p
, tsubst_flags_t complain
)
9043 struct z_candidate
*candidates
= 0, *cand
;
9044 tree explicit_targs
= NULL_TREE
;
9045 tree basetype
= NULL_TREE
;
9046 tree access_binfo
, binfo
;
9048 tree first_mem_arg
= NULL_TREE
;
9050 bool skip_first_for_error
;
9051 vec
<tree
, va_gc
> *user_args
;
9054 int template_only
= 0;
9058 vec
<tree
, va_gc
> *orig_args
= NULL
;
9061 gcc_assert (instance
!= NULL_TREE
);
9063 /* We don't know what function we're going to call, yet. */
9067 if (error_operand_p (instance
)
9068 || !fns
|| error_operand_p (fns
))
9069 return error_mark_node
;
9071 if (!BASELINK_P (fns
))
9073 if (complain
& tf_error
)
9074 error ("call to non-function %qD", fns
);
9075 return error_mark_node
;
9078 orig_instance
= instance
;
9081 /* Dismantle the baselink to collect all the information we need. */
9082 if (!conversion_path
)
9083 conversion_path
= BASELINK_BINFO (fns
);
9084 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9085 binfo
= BASELINK_BINFO (fns
);
9086 optype
= BASELINK_OPTYPE (fns
);
9087 fns
= BASELINK_FUNCTIONS (fns
);
9088 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9090 explicit_targs
= TREE_OPERAND (fns
, 1);
9091 fns
= TREE_OPERAND (fns
, 0);
9094 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
9095 || TREE_CODE (fns
) == TEMPLATE_DECL
9096 || TREE_CODE (fns
) == OVERLOAD
);
9097 fn
= OVL_FIRST (fns
);
9098 name
= DECL_NAME (fn
);
9100 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9101 gcc_assert (CLASS_TYPE_P (basetype
));
9103 if (processing_template_decl
)
9105 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9106 instance
= build_non_dependent_expr (instance
);
9108 make_args_non_dependent (*args
);
9111 user_args
= args
== NULL
? NULL
: *args
;
9112 /* Under DR 147 A::A() is an invalid constructor call,
9113 not a functional cast. */
9114 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9116 if (! (complain
& tf_error
))
9117 return error_mark_node
;
9119 basetype
= DECL_CONTEXT (fn
);
9120 name
= constructor_name (basetype
);
9121 if (permerror (input_location
,
9122 "cannot call constructor %<%T::%D%> directly",
9124 inform (input_location
, "for a function-style cast, remove the "
9125 "redundant %<::%D%>", name
);
9126 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9131 /* Process the argument list. */
9132 if (args
!= NULL
&& *args
!= NULL
)
9134 *args
= resolve_args (*args
, complain
);
9136 return error_mark_node
;
9139 /* Consider the object argument to be used even if we end up selecting a
9140 static member function. */
9141 instance
= mark_type_use (instance
);
9143 /* Figure out whether to skip the first argument for the error
9144 message we will display to users if an error occurs. We don't
9145 want to display any compiler-generated arguments. The "this"
9146 pointer hasn't been added yet. However, we must remove the VTT
9147 pointer if this is a call to a base-class constructor or
9149 skip_first_for_error
= false;
9150 if (IDENTIFIER_CDTOR_P (name
))
9152 /* Callers should explicitly indicate whether they want to ctor
9153 the complete object or just the part without virtual bases. */
9154 gcc_assert (name
!= ctor_identifier
);
9156 /* Remove the VTT pointer, if present. */
9157 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9158 && CLASSTYPE_VBASECLASSES (basetype
))
9159 skip_first_for_error
= true;
9161 /* It's OK to call destructors and constructors on cv-qualified
9162 objects. Therefore, convert the INSTANCE to the unqualified
9163 type, if necessary. */
9164 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9166 instance
= build_this (instance
);
9167 instance
= build_nop (build_pointer_type (basetype
), instance
);
9168 instance
= build_fold_indirect_ref (instance
);
9172 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9174 /* For the overload resolution we need to find the actual `this`
9175 that would be captured if the call turns out to be to a
9176 non-static member function. Do not actually capture it at this
9178 if (DECL_CONSTRUCTOR_P (fn
))
9179 /* Constructors don't use the enclosing 'this'. */
9180 first_mem_arg
= instance
;
9182 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9184 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9185 p
= conversion_obstack_alloc (0);
9187 /* The number of arguments artificial parms in ARGS; we subtract one because
9188 there's no 'this' in ARGS. */
9189 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9191 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9192 initializer, not T({ }). */
9193 if (DECL_CONSTRUCTOR_P (fn
)
9194 && vec_safe_length (user_args
) > skip
9195 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9197 tree init_list
= (*user_args
)[skip
];
9198 tree init
= NULL_TREE
;
9200 gcc_assert (user_args
->length () == skip
+ 1
9201 && !(flags
& LOOKUP_ONLYCONVERTING
));
9203 /* If the initializer list has no elements and T is a class type with
9204 a default constructor, the object is value-initialized. Handle
9205 this here so we don't need to handle it wherever we use
9206 build_special_member_call. */
9207 if (CONSTRUCTOR_NELTS (init_list
) == 0
9208 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9209 /* For a user-provided default constructor, use the normal
9210 mechanisms so that protected access works. */
9211 && type_has_non_user_provided_default_constructor (basetype
)
9212 && !processing_template_decl
)
9213 init
= build_value_init (basetype
, complain
);
9215 /* If BASETYPE is an aggregate, we need to do aggregate
9217 else if (CP_AGGREGATE_TYPE_P (basetype
))
9219 init
= reshape_init (basetype
, init_list
, complain
);
9220 init
= digest_init (basetype
, init
, complain
);
9225 if (is_dummy_object (instance
))
9226 return get_target_expr_sfinae (init
, complain
);
9227 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9228 TREE_SIDE_EFFECTS (init
) = true;
9232 /* Otherwise go ahead with overload resolution. */
9233 add_list_candidates (fns
, first_mem_arg
, user_args
,
9234 basetype
, explicit_targs
, template_only
,
9235 conversion_path
, access_binfo
, flags
,
9236 &candidates
, complain
);
9239 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9240 explicit_targs
, template_only
, conversion_path
,
9241 access_binfo
, flags
, &candidates
, complain
);
9243 any_viable_p
= false;
9244 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9248 if (complain
& tf_error
)
9250 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9251 cxx_incomplete_type_error (instance
, basetype
);
9253 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9254 basetype
, optype
, build_tree_list_vec (user_args
),
9255 TREE_TYPE (instance
));
9258 tree arglist
= build_tree_list_vec (user_args
);
9259 tree errname
= name
;
9260 bool twiddle
= false;
9261 if (IDENTIFIER_CDTOR_P (errname
))
9263 twiddle
= IDENTIFIER_DTOR_P (errname
);
9264 errname
= constructor_name (basetype
);
9267 errname
= lookup_template_function (errname
, explicit_targs
);
9268 if (skip_first_for_error
)
9269 arglist
= TREE_CHAIN (arglist
);
9270 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9271 basetype
, &"~"[!twiddle
], errname
, arglist
,
9272 TREE_TYPE (instance
));
9274 print_z_candidates (location_of (name
), candidates
);
9276 call
= error_mark_node
;
9280 cand
= tourney (candidates
, complain
);
9287 if (complain
& tf_error
)
9289 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9290 arglist
= build_tree_list_vec (user_args
);
9291 if (skip_first_for_error
)
9292 arglist
= TREE_CHAIN (arglist
);
9293 if (!any_strictly_viable (candidates
))
9294 error ("no matching function for call to %<%s(%A)%>",
9295 pretty_name
, arglist
);
9297 error ("call of overloaded %<%s(%A)%> is ambiguous",
9298 pretty_name
, arglist
);
9299 print_z_candidates (location_of (name
), candidates
);
9303 call
= error_mark_node
;
9310 if (!(flags
& LOOKUP_NONVIRTUAL
)
9311 && DECL_PURE_VIRTUAL_P (fn
)
9312 && instance
== current_class_ref
9313 && (complain
& tf_warning
))
9315 /* This is not an error, it is runtime undefined
9317 if (!current_function_decl
)
9318 warning (0, "pure virtual %q#D called from "
9319 "non-static data member initializer", fn
);
9320 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9321 || DECL_DESTRUCTOR_P (current_function_decl
))
9322 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9323 ? G_("pure virtual %q#D called from constructor")
9324 : G_("pure virtual %q#D called from destructor")),
9328 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9329 && !DECL_CONSTRUCTOR_P (fn
)
9330 && is_dummy_object (instance
))
9332 instance
= maybe_resolve_dummy (instance
, true);
9333 if (instance
== error_mark_node
)
9334 call
= error_mark_node
;
9335 else if (!is_dummy_object (instance
))
9337 /* We captured 'this' in the current lambda now that
9338 we know we really need it. */
9339 cand
->first_arg
= instance
;
9341 else if (any_dependent_bases_p ())
9342 /* We can't tell until instantiation time whether we can use
9343 *this as the implicit object argument. */;
9346 if (complain
& tf_error
)
9347 error ("cannot call member function %qD without object",
9349 call
= error_mark_node
;
9353 if (call
!= error_mark_node
)
9355 /* Optimize away vtable lookup if we know that this
9356 function can't be overridden. We need to check if
9357 the context and the type where we found fn are the same,
9358 actually FN might be defined in a different class
9359 type because of a using-declaration. In this case, we
9360 do not want to perform a non-virtual call. */
9361 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9362 && same_type_ignoring_top_level_qualifiers_p
9363 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9364 && resolves_to_fixed_type_p (instance
, 0))
9365 flags
|= LOOKUP_NONVIRTUAL
;
9367 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9368 /* Now we know what function is being called. */
9371 /* Build the actual CALL_EXPR. */
9372 call
= build_over_call (cand
, flags
, complain
);
9373 /* In an expression of the form `a->f()' where `f' turns
9374 out to be a static member function, `a' is
9375 none-the-less evaluated. */
9376 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9377 && !is_dummy_object (instance
)
9378 && TREE_SIDE_EFFECTS (instance
))
9380 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9383 if (TREE_THIS_VOLATILE (a
))
9385 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9387 else if (call
!= error_mark_node
9388 && DECL_DESTRUCTOR_P (cand
->fn
)
9389 && !VOID_TYPE_P (TREE_TYPE (call
)))
9390 /* An explicit call of the form "x->~X()" has type
9391 "void". However, on platforms where destructors
9392 return "this" (i.e., those where
9393 targetm.cxx.cdtor_returns_this is true), such calls
9394 will appear to have a return value of pointer type
9395 to the low-level call machinery. We do not want to
9396 change the low-level machinery, since we want to be
9397 able to optimize "delete f()" on such platforms as
9398 "operator delete(~X(f()))" (rather than generating
9399 "t = f(), ~X(t), operator delete (t)"). */
9400 call
= build_nop (void_type_node
, call
);
9405 if (processing_template_decl
&& call
!= error_mark_node
)
9407 bool cast_to_void
= false;
9409 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9410 call
= TREE_OPERAND (call
, 1);
9411 else if (TREE_CODE (call
) == NOP_EXPR
)
9413 cast_to_void
= true;
9414 call
= TREE_OPERAND (call
, 0);
9416 if (INDIRECT_REF_P (call
))
9417 call
= TREE_OPERAND (call
, 0);
9418 call
= (build_min_non_dep_call_vec
9420 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9421 orig_instance
, orig_fns
, NULL_TREE
),
9423 SET_EXPR_LOCATION (call
, input_location
);
9424 call
= convert_from_reference (call
);
9426 call
= build_nop (void_type_node
, call
);
9429 /* Free all the conversions we allocated. */
9430 obstack_free (&conversion_obstack
, p
);
9432 if (orig_args
!= NULL
)
9433 release_tree_vector (orig_args
);
9438 /* Wrapper for above. */
9441 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9442 tree conversion_path
, int flags
,
9443 tree
*fn_p
, tsubst_flags_t complain
)
9446 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9447 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9449 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9453 /* Returns true iff standard conversion sequence ICS1 is a proper
9454 subsequence of ICS2. */
9457 is_subseq (conversion
*ics1
, conversion
*ics2
)
9459 /* We can assume that a conversion of the same code
9460 between the same types indicates a subsequence since we only get
9461 here if the types we are converting from are the same. */
9463 while (ics1
->kind
== ck_rvalue
9464 || ics1
->kind
== ck_lvalue
)
9465 ics1
= next_conversion (ics1
);
9469 while (ics2
->kind
== ck_rvalue
9470 || ics2
->kind
== ck_lvalue
)
9471 ics2
= next_conversion (ics2
);
9473 if (ics2
->kind
== ck_user
9474 || ics2
->kind
== ck_ambig
9475 || ics2
->kind
== ck_aggr
9476 || ics2
->kind
== ck_list
9477 || ics2
->kind
== ck_identity
)
9478 /* At this point, ICS1 cannot be a proper subsequence of
9479 ICS2. We can get a USER_CONV when we are comparing the
9480 second standard conversion sequence of two user conversion
9484 ics2
= next_conversion (ics2
);
9486 while (ics2
->kind
== ck_rvalue
9487 || ics2
->kind
== ck_lvalue
)
9488 ics2
= next_conversion (ics2
);
9490 if (ics2
->kind
== ics1
->kind
9491 && same_type_p (ics2
->type
, ics1
->type
)
9492 && (ics1
->kind
== ck_identity
9493 || same_type_p (next_conversion (ics2
)->type
,
9494 next_conversion (ics1
)->type
)))
9499 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9500 be any _TYPE nodes. */
9503 is_properly_derived_from (tree derived
, tree base
)
9505 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
9508 /* We only allow proper derivation here. The DERIVED_FROM_P macro
9509 considers every class derived from itself. */
9510 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
9511 && DERIVED_FROM_P (base
, derived
));
9514 /* We build the ICS for an implicit object parameter as a pointer
9515 conversion sequence. However, such a sequence should be compared
9516 as if it were a reference conversion sequence. If ICS is the
9517 implicit conversion sequence for an implicit object parameter,
9518 modify it accordingly. */
9521 maybe_handle_implicit_object (conversion
**ics
)
9525 /* [over.match.funcs]
9527 For non-static member functions, the type of the
9528 implicit object parameter is "reference to cv X"
9529 where X is the class of which the function is a
9530 member and cv is the cv-qualification on the member
9531 function declaration. */
9532 conversion
*t
= *ics
;
9533 tree reference_type
;
9535 /* The `this' parameter is a pointer to a class type. Make the
9536 implicit conversion talk about a reference to that same class
9538 reference_type
= TREE_TYPE (t
->type
);
9539 reference_type
= build_reference_type (reference_type
);
9541 if (t
->kind
== ck_qual
)
9542 t
= next_conversion (t
);
9543 if (t
->kind
== ck_ptr
)
9544 t
= next_conversion (t
);
9545 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
9546 t
= direct_reference_binding (reference_type
, t
);
9548 t
->rvaluedness_matches_p
= 0;
9553 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
9554 and return the initial reference binding conversion. Otherwise,
9555 leave *ICS unchanged and return NULL. */
9558 maybe_handle_ref_bind (conversion
**ics
)
9560 if ((*ics
)->kind
== ck_ref_bind
)
9562 conversion
*old_ics
= *ics
;
9563 *ics
= next_conversion (old_ics
);
9564 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
9571 /* Compare two implicit conversion sequences according to the rules set out in
9572 [over.ics.rank]. Return values:
9574 1: ics1 is better than ics2
9575 -1: ics2 is better than ics1
9576 0: ics1 and ics2 are indistinguishable */
9579 compare_ics (conversion
*ics1
, conversion
*ics2
)
9585 tree deref_from_type1
= NULL_TREE
;
9586 tree deref_from_type2
= NULL_TREE
;
9587 tree deref_to_type1
= NULL_TREE
;
9588 tree deref_to_type2
= NULL_TREE
;
9589 conversion_rank rank1
, rank2
;
9591 /* REF_BINDING is nonzero if the result of the conversion sequence
9592 is a reference type. In that case REF_CONV is the reference
9593 binding conversion. */
9594 conversion
*ref_conv1
;
9595 conversion
*ref_conv2
;
9597 /* Compare badness before stripping the reference conversion. */
9598 if (ics1
->bad_p
> ics2
->bad_p
)
9600 else if (ics1
->bad_p
< ics2
->bad_p
)
9603 /* Handle implicit object parameters. */
9604 maybe_handle_implicit_object (&ics1
);
9605 maybe_handle_implicit_object (&ics2
);
9607 /* Handle reference parameters. */
9608 ref_conv1
= maybe_handle_ref_bind (&ics1
);
9609 ref_conv2
= maybe_handle_ref_bind (&ics2
);
9611 /* List-initialization sequence L1 is a better conversion sequence than
9612 list-initialization sequence L2 if L1 converts to
9613 std::initializer_list<X> for some X and L2 does not. */
9614 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
9616 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
9621 When comparing the basic forms of implicit conversion sequences (as
9622 defined in _over.best.ics_)
9624 --a standard conversion sequence (_over.ics.scs_) is a better
9625 conversion sequence than a user-defined conversion sequence
9626 or an ellipsis conversion sequence, and
9628 --a user-defined conversion sequence (_over.ics.user_) is a
9629 better conversion sequence than an ellipsis conversion sequence
9630 (_over.ics.ellipsis_). */
9631 /* Use BAD_CONVERSION_RANK because we already checked for a badness
9632 mismatch. If both ICS are bad, we try to make a decision based on
9633 what would have happened if they'd been good. This is not an
9634 extension, we'll still give an error when we build up the call; this
9635 just helps us give a more helpful error message. */
9636 rank1
= BAD_CONVERSION_RANK (ics1
);
9637 rank2
= BAD_CONVERSION_RANK (ics2
);
9641 else if (rank1
< rank2
)
9644 if (ics1
->ellipsis_p
)
9645 /* Both conversions are ellipsis conversions. */
9648 /* User-defined conversion sequence U1 is a better conversion sequence
9649 than another user-defined conversion sequence U2 if they contain the
9650 same user-defined conversion operator or constructor and if the sec-
9651 ond standard conversion sequence of U1 is better than the second
9652 standard conversion sequence of U2. */
9654 /* Handle list-conversion with the same code even though it isn't always
9655 ranked as a user-defined conversion and it doesn't have a second
9656 standard conversion sequence; it will still have the desired effect.
9657 Specifically, we need to do the reference binding comparison at the
9658 end of this function. */
9660 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
|| ics1
->kind
== ck_aggr
)
9665 for (t1
= ics1
; t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
9666 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
9667 || t1
->kind
== ck_list
)
9669 for (t2
= ics2
; t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
9670 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
9671 || t2
->kind
== ck_list
)
9674 if (t1
->kind
!= t2
->kind
)
9676 else if (t1
->kind
== ck_user
)
9678 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
9679 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
9685 /* For ambiguous or aggregate conversions, use the target type as
9686 a proxy for the conversion function. */
9687 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
9691 /* We can just fall through here, after setting up
9692 FROM_TYPE1 and FROM_TYPE2. */
9693 from_type1
= t1
->type
;
9694 from_type2
= t2
->type
;
9701 /* We're dealing with two standard conversion sequences.
9705 Standard conversion sequence S1 is a better conversion
9706 sequence than standard conversion sequence S2 if
9708 --S1 is a proper subsequence of S2 (comparing the conversion
9709 sequences in the canonical form defined by _over.ics.scs_,
9710 excluding any Lvalue Transformation; the identity
9711 conversion sequence is considered to be a subsequence of
9712 any non-identity conversion sequence */
9715 while (t1
->kind
!= ck_identity
)
9716 t1
= next_conversion (t1
);
9717 from_type1
= t1
->type
;
9720 while (t2
->kind
!= ck_identity
)
9721 t2
= next_conversion (t2
);
9722 from_type2
= t2
->type
;
9725 /* One sequence can only be a subsequence of the other if they start with
9726 the same type. They can start with different types when comparing the
9727 second standard conversion sequence in two user-defined conversion
9729 if (same_type_p (from_type1
, from_type2
))
9731 if (is_subseq (ics1
, ics2
))
9733 if (is_subseq (ics2
, ics1
))
9741 --the rank of S1 is better than the rank of S2 (by the rules
9744 Standard conversion sequences are ordered by their ranks: an Exact
9745 Match is a better conversion than a Promotion, which is a better
9746 conversion than a Conversion.
9748 Two conversion sequences with the same rank are indistinguishable
9749 unless one of the following rules applies:
9751 --A conversion that does not a convert a pointer, pointer to member,
9752 or std::nullptr_t to bool is better than one that does.
9754 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
9755 so that we do not have to check it explicitly. */
9756 if (ics1
->rank
< ics2
->rank
)
9758 else if (ics2
->rank
< ics1
->rank
)
9761 to_type1
= ics1
->type
;
9762 to_type2
= ics2
->type
;
9764 /* A conversion from scalar arithmetic type to complex is worse than a
9765 conversion between scalar arithmetic types. */
9766 if (same_type_p (from_type1
, from_type2
)
9767 && ARITHMETIC_TYPE_P (from_type1
)
9768 && ARITHMETIC_TYPE_P (to_type1
)
9769 && ARITHMETIC_TYPE_P (to_type2
)
9770 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
9771 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
9773 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
9779 if (TYPE_PTR_P (from_type1
)
9780 && TYPE_PTR_P (from_type2
)
9781 && TYPE_PTR_P (to_type1
)
9782 && TYPE_PTR_P (to_type2
))
9784 deref_from_type1
= TREE_TYPE (from_type1
);
9785 deref_from_type2
= TREE_TYPE (from_type2
);
9786 deref_to_type1
= TREE_TYPE (to_type1
);
9787 deref_to_type2
= TREE_TYPE (to_type2
);
9789 /* The rules for pointers to members A::* are just like the rules
9790 for pointers A*, except opposite: if B is derived from A then
9791 A::* converts to B::*, not vice versa. For that reason, we
9792 switch the from_ and to_ variables here. */
9793 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
9794 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
9795 || (TYPE_PTRMEMFUNC_P (from_type1
)
9796 && TYPE_PTRMEMFUNC_P (from_type2
)
9797 && TYPE_PTRMEMFUNC_P (to_type1
)
9798 && TYPE_PTRMEMFUNC_P (to_type2
)))
9800 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
9801 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
9802 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
9803 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
9806 if (deref_from_type1
!= NULL_TREE
9807 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
9808 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
9810 /* This was one of the pointer or pointer-like conversions.
9814 --If class B is derived directly or indirectly from class A,
9815 conversion of B* to A* is better than conversion of B* to
9816 void*, and conversion of A* to void* is better than
9817 conversion of B* to void*. */
9818 if (VOID_TYPE_P (deref_to_type1
)
9819 && VOID_TYPE_P (deref_to_type2
))
9821 if (is_properly_derived_from (deref_from_type1
,
9824 else if (is_properly_derived_from (deref_from_type2
,
9828 else if (VOID_TYPE_P (deref_to_type1
)
9829 || VOID_TYPE_P (deref_to_type2
))
9831 if (same_type_p (deref_from_type1
, deref_from_type2
))
9833 if (VOID_TYPE_P (deref_to_type2
))
9835 if (is_properly_derived_from (deref_from_type1
,
9839 /* We know that DEREF_TO_TYPE1 is `void' here. */
9840 else if (is_properly_derived_from (deref_from_type1
,
9845 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
9846 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
9850 --If class B is derived directly or indirectly from class A
9851 and class C is derived directly or indirectly from B,
9853 --conversion of C* to B* is better than conversion of C* to
9856 --conversion of B* to A* is better than conversion of C* to
9858 if (same_type_p (deref_from_type1
, deref_from_type2
))
9860 if (is_properly_derived_from (deref_to_type1
,
9863 else if (is_properly_derived_from (deref_to_type2
,
9867 else if (same_type_p (deref_to_type1
, deref_to_type2
))
9869 if (is_properly_derived_from (deref_from_type2
,
9872 else if (is_properly_derived_from (deref_from_type1
,
9878 else if (CLASS_TYPE_P (non_reference (from_type1
))
9879 && same_type_p (from_type1
, from_type2
))
9881 tree from
= non_reference (from_type1
);
9885 --binding of an expression of type C to a reference of type
9886 B& is better than binding an expression of type C to a
9887 reference of type A&
9889 --conversion of C to B is better than conversion of C to A, */
9890 if (is_properly_derived_from (from
, to_type1
)
9891 && is_properly_derived_from (from
, to_type2
))
9893 if (is_properly_derived_from (to_type1
, to_type2
))
9895 else if (is_properly_derived_from (to_type2
, to_type1
))
9899 else if (CLASS_TYPE_P (non_reference (to_type1
))
9900 && same_type_p (to_type1
, to_type2
))
9902 tree to
= non_reference (to_type1
);
9906 --binding of an expression of type B to a reference of type
9907 A& is better than binding an expression of type C to a
9908 reference of type A&,
9910 --conversion of B to A is better than conversion of C to A */
9911 if (is_properly_derived_from (from_type1
, to
)
9912 && is_properly_derived_from (from_type2
, to
))
9914 if (is_properly_derived_from (from_type2
, from_type1
))
9916 else if (is_properly_derived_from (from_type1
, from_type2
))
9923 --S1 and S2 differ only in their qualification conversion and yield
9924 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
9925 qualification signature of type T1 is a proper subset of the cv-
9926 qualification signature of type T2 */
9927 if (ics1
->kind
== ck_qual
9928 && ics2
->kind
== ck_qual
9929 && same_type_p (from_type1
, from_type2
))
9931 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
9938 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
9939 to an implicit object parameter of a non-static member function
9940 declared without a ref-qualifier, and either S1 binds an lvalue
9941 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
9942 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
9943 draft standard, 13.3.3.2)
9945 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
9946 types to which the references refer are the same type except for
9947 top-level cv-qualifiers, and the type to which the reference
9948 initialized by S2 refers is more cv-qualified than the type to
9949 which the reference initialized by S1 refers.
9951 DR 1328 [over.match.best]: the context is an initialization by
9952 conversion function for direct reference binding (13.3.1.6) of a
9953 reference to function type, the return type of F1 is the same kind of
9954 reference (i.e. lvalue or rvalue) as the reference being initialized,
9955 and the return type of F2 is not. */
9957 if (ref_conv1
&& ref_conv2
)
9959 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
9960 && (ref_conv1
->rvaluedness_matches_p
9961 != ref_conv2
->rvaluedness_matches_p
)
9962 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
9963 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
9964 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
9966 if (ref_conv1
->bad_p
9967 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
9968 TREE_TYPE (ref_conv2
->type
)))
9969 /* Don't prefer a bad conversion that drops cv-quals to a bad
9970 conversion with the wrong rvalueness. */
9972 return (ref_conv1
->rvaluedness_matches_p
9973 - ref_conv2
->rvaluedness_matches_p
);
9976 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
9978 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
9979 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
9980 if (ref_conv1
->bad_p
)
9982 /* Prefer the one that drops fewer cv-quals. */
9983 tree ftype
= next_conversion (ref_conv1
)->type
;
9984 int fquals
= cp_type_quals (ftype
);
9988 return comp_cv_qualification (q2
, q1
);
9992 /* Neither conversion sequence is better than the other. */
9996 /* The source type for this standard conversion sequence. */
9999 source_type (conversion
*t
)
10001 for (;; t
= next_conversion (t
))
10003 if (t
->kind
== ck_user
10004 || t
->kind
== ck_ambig
10005 || t
->kind
== ck_identity
)
10008 gcc_unreachable ();
10011 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10012 a pointer to LOSER and re-running joust to produce the warning if WINNER
10013 is actually used. */
10016 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10018 candidate_warning
*cw
= (candidate_warning
*)
10019 conversion_obstack_alloc (sizeof (candidate_warning
));
10021 cw
->next
= winner
->warnings
;
10022 winner
->warnings
= cw
;
10025 /* Compare two candidates for overloading as described in
10026 [over.match.best]. Return values:
10028 1: cand1 is better than cand2
10029 -1: cand2 is better than cand1
10030 0: cand1 and cand2 are indistinguishable */
10033 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10034 tsubst_flags_t complain
)
10037 int off1
= 0, off2
= 0;
10041 /* Candidates that involve bad conversions are always worse than those
10043 if (cand1
->viable
> cand2
->viable
)
10045 if (cand1
->viable
< cand2
->viable
)
10048 /* If we have two pseudo-candidates for conversions to the same type,
10049 or two candidates for the same function, arbitrarily pick one. */
10050 if (cand1
->fn
== cand2
->fn
10051 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10054 /* Prefer a non-deleted function over an implicitly deleted move
10055 constructor or assignment operator. This differs slightly from the
10056 wording for issue 1402 (which says the move op is ignored by overload
10057 resolution), but this way produces better error messages. */
10058 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10059 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10060 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10062 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10063 && move_fn_p (cand1
->fn
))
10065 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10066 && move_fn_p (cand2
->fn
))
10070 /* a viable function F1
10071 is defined to be a better function than another viable function F2 if
10072 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10073 ICSi(F2), and then */
10075 /* for some argument j, ICSj(F1) is a better conversion sequence than
10078 /* For comparing static and non-static member functions, we ignore
10079 the implicit object parameter of the non-static function. The
10080 standard says to pretend that the static function has an object
10081 parm, but that won't work with operator overloading. */
10082 len
= cand1
->num_convs
;
10083 if (len
!= cand2
->num_convs
)
10085 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10086 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10088 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10089 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10090 /* We're comparing a near-match list constructor and a near-match
10091 non-list constructor. Just treat them as unordered. */
10094 gcc_assert (static_1
!= static_2
);
10105 for (i
= 0; i
< len
; ++i
)
10107 conversion
*t1
= cand1
->convs
[i
+ off1
];
10108 conversion
*t2
= cand2
->convs
[i
+ off2
];
10109 int comp
= compare_ics (t1
, t2
);
10113 if ((complain
& tf_warning
)
10115 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10116 == cr_std
+ cr_promotion
)
10117 && t1
->kind
== ck_std
10118 && t2
->kind
== ck_std
10119 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10120 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10121 && (TYPE_PRECISION (t1
->type
)
10122 == TYPE_PRECISION (t2
->type
))
10123 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10124 || (TREE_CODE (next_conversion (t1
)->type
)
10125 == ENUMERAL_TYPE
)))
10127 tree type
= next_conversion (t1
)->type
;
10129 struct z_candidate
*w
, *l
;
10131 type1
= t1
->type
, type2
= t2
->type
,
10132 w
= cand1
, l
= cand2
;
10134 type1
= t2
->type
, type2
= t1
->type
,
10135 w
= cand2
, l
= cand1
;
10139 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10140 type
, type1
, type2
);
10141 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10144 add_warning (w
, l
);
10147 if (winner
&& comp
!= winner
)
10156 /* warn about confusing overload resolution for user-defined conversions,
10157 either between a constructor and a conversion op, or between two
10159 if ((complain
& tf_warning
)
10160 && winner
&& warn_conversion
&& cand1
->second_conv
10161 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10162 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10164 struct z_candidate
*w
, *l
;
10165 bool give_warning
= false;
10168 w
= cand1
, l
= cand2
;
10170 w
= cand2
, l
= cand1
;
10172 /* We don't want to complain about `X::operator T1 ()'
10173 beating `X::operator T2 () const', when T2 is a no less
10174 cv-qualified version of T1. */
10175 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10176 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10178 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10179 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10181 if (TREE_CODE (t
) == TREE_CODE (f
) && POINTER_TYPE_P (t
))
10186 if (!comp_ptr_ttypes (t
, f
))
10187 give_warning
= true;
10190 give_warning
= true;
10196 tree source
= source_type (w
->convs
[0]);
10197 if (POINTER_TYPE_P (source
))
10198 source
= TREE_TYPE (source
);
10199 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10200 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10201 source
, w
->second_conv
->type
))
10203 inform (input_location
, " because conversion sequence for the argument is better");
10207 add_warning (w
, l
);
10213 /* DR 495 moved this tiebreaker above the template ones. */
10214 /* or, if not that,
10215 the context is an initialization by user-defined conversion (see
10216 _dcl.init_ and _over.match.user_) and the standard conversion
10217 sequence from the return type of F1 to the destination type (i.e.,
10218 the type of the entity being initialized) is a better conversion
10219 sequence than the standard conversion sequence from the return type
10220 of F2 to the destination type. */
10222 if (cand1
->second_conv
)
10224 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10229 /* or, if not that,
10230 F1 is a non-template function and F2 is a template function
10233 if (!cand1
->template_decl
&& cand2
->template_decl
)
10235 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10238 /* or, if not that,
10239 F1 and F2 are template functions and the function template for F1 is
10240 more specialized than the template for F2 according to the partial
10243 if (cand1
->template_decl
&& cand2
->template_decl
)
10245 winner
= more_specialized_fn
10246 (TI_TEMPLATE (cand1
->template_decl
),
10247 TI_TEMPLATE (cand2
->template_decl
),
10248 /* [temp.func.order]: The presence of unused ellipsis and default
10249 arguments has no effect on the partial ordering of function
10250 templates. add_function_candidate() will not have
10251 counted the "this" argument for constructors. */
10252 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10258 // or, if not that, F1 is more constrained than F2.
10259 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10261 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10266 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10267 if (deduction_guide_p (cand1
->fn
))
10269 gcc_assert (deduction_guide_p (cand2
->fn
));
10270 /* We distinguish between candidates from an explicit deduction guide and
10271 candidates built from a constructor based on DECL_ARTIFICIAL. */
10272 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10273 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10275 return art2
- art1
;
10279 /* Prefer the special copy guide over a declared copy/move
10281 if (copy_guide_p (cand1
->fn
))
10283 if (copy_guide_p (cand2
->fn
))
10286 /* Prefer a candidate generated from a non-template constructor. */
10287 int tg1
= template_guide_p (cand1
->fn
);
10288 int tg2
= template_guide_p (cand2
->fn
);
10294 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10295 for all arguments the corresponding parameters of F1 and F2 have the same
10296 type (CWG 2273/2277). */
10297 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10298 && !DECL_CONV_FN_P (cand1
->fn
)
10299 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10300 && !DECL_CONV_FN_P (cand2
->fn
))
10302 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10303 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10305 bool used1
= false;
10306 bool used2
= false;
10307 if (base1
== base2
)
10308 /* No difference. */;
10309 else if (DERIVED_FROM_P (base1
, base2
))
10311 else if (DERIVED_FROM_P (base2
, base1
))
10314 if (int diff
= used2
- used1
)
10316 for (i
= 0; i
< len
; ++i
)
10318 conversion
*t1
= cand1
->convs
[i
+ off1
];
10319 conversion
*t2
= cand2
->convs
[i
+ off2
];
10320 if (!same_type_p (t1
->type
, t2
->type
))
10328 /* Check whether we can discard a builtin candidate, either because we
10329 have two identical ones or matching builtin and non-builtin candidates.
10331 (Pedantically in the latter case the builtin which matched the user
10332 function should not be added to the overload set, but we spot it here.
10335 ... the builtin candidates include ...
10336 - do not have the same parameter type list as any non-template
10337 non-member candidate. */
10339 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10341 for (i
= 0; i
< len
; ++i
)
10342 if (!same_type_p (cand1
->convs
[i
]->type
,
10343 cand2
->convs
[i
]->type
))
10345 if (i
== cand1
->num_convs
)
10347 if (cand1
->fn
== cand2
->fn
)
10348 /* Two built-in candidates; arbitrarily pick one. */
10350 else if (identifier_p (cand1
->fn
))
10351 /* cand1 is built-in; prefer cand2. */
10354 /* cand2 is built-in; prefer cand1. */
10359 /* For candidates of a multi-versioned function, make the version with
10360 the highest priority win. This version will be checked for dispatching
10361 first. If this version can be inlined into the caller, the front-end
10362 will simply make a direct call to this function. */
10364 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10365 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10366 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10367 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10369 tree f1
= TREE_TYPE (cand1
->fn
);
10370 tree f2
= TREE_TYPE (cand2
->fn
);
10371 tree p1
= TYPE_ARG_TYPES (f1
);
10372 tree p2
= TYPE_ARG_TYPES (f2
);
10374 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10375 is possible that cand1->fn and cand2->fn are function versions but of
10376 different functions. Check types to see if they are versions of the same
10378 if (compparms (p1
, p2
)
10379 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10381 /* Always make the version with the higher priority, more
10382 specialized, win. */
10383 gcc_assert (targetm
.compare_version_priority
);
10384 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10391 /* If the two function declarations represent the same function (this can
10392 happen with declarations in multiple scopes and arg-dependent lookup),
10393 arbitrarily choose one. But first make sure the default args we're
10395 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10396 && equal_functions (cand1
->fn
, cand2
->fn
))
10398 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10399 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10401 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10403 for (i
= 0; i
< len
; ++i
)
10405 /* Don't crash if the fn is variadic. */
10408 parms1
= TREE_CHAIN (parms1
);
10409 parms2
= TREE_CHAIN (parms2
);
10413 parms1
= TREE_CHAIN (parms1
);
10415 parms2
= TREE_CHAIN (parms2
);
10417 for (; parms1
; ++i
)
10419 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10420 TREE_PURPOSE (parms2
)))
10424 if (complain
& tf_error
)
10426 if (permerror (input_location
,
10427 "default argument mismatch in "
10428 "overload resolution"))
10430 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10431 " candidate 1: %q#F", cand1
->fn
);
10432 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10433 " candidate 2: %q#F", cand2
->fn
);
10440 add_warning (cand1
, cand2
);
10443 parms1
= TREE_CHAIN (parms1
);
10444 parms2
= TREE_CHAIN (parms2
);
10452 /* Extension: If the worst conversion for one candidate is worse than the
10453 worst conversion for the other, take the first. */
10454 if (!pedantic
&& (complain
& tf_warning_or_error
))
10456 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
10457 struct z_candidate
*w
= 0, *l
= 0;
10459 for (i
= 0; i
< len
; ++i
)
10461 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
10462 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
10463 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
10464 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
10467 winner
= 1, w
= cand1
, l
= cand2
;
10469 winner
= -1, w
= cand2
, l
= cand1
;
10472 /* Don't choose a deleted function over ambiguity. */
10473 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
10477 pedwarn (input_location
, 0,
10478 "ISO C++ says that these are ambiguous, even "
10479 "though the worst conversion for the first is better than "
10480 "the worst conversion for the second:");
10481 print_z_candidate (input_location
, _("candidate 1:"), w
);
10482 print_z_candidate (input_location
, _("candidate 2:"), l
);
10485 add_warning (w
, l
);
10490 gcc_assert (!winner
);
10494 /* Given a list of candidates for overloading, find the best one, if any.
10495 This algorithm has a worst case of O(2n) (winner is last), and a best
10496 case of O(n/2) (totally ambiguous); much better than a sorting
10499 static struct z_candidate
*
10500 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
10502 struct z_candidate
*champ
= candidates
, *challenger
;
10504 int champ_compared_to_predecessor
= 0;
10506 /* Walk through the list once, comparing each current champ to the next
10507 candidate, knocking out a candidate or two with each comparison. */
10509 for (challenger
= champ
->next
; challenger
; )
10511 fate
= joust (champ
, challenger
, 0, complain
);
10513 challenger
= challenger
->next
;
10518 champ
= challenger
->next
;
10521 champ_compared_to_predecessor
= 0;
10525 champ
= challenger
;
10526 champ_compared_to_predecessor
= 1;
10529 challenger
= champ
->next
;
10533 /* Make sure the champ is better than all the candidates it hasn't yet
10534 been compared to. */
10536 for (challenger
= candidates
;
10537 challenger
!= champ
10538 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
10539 challenger
= challenger
->next
)
10541 fate
= joust (champ
, challenger
, 0, complain
);
10549 /* Returns nonzero if things of type FROM can be converted to TO. */
10552 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
10554 tree arg
= NULL_TREE
;
10555 /* implicit_conversion only considers user-defined conversions
10556 if it has an expression for the call argument list. */
10557 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
10558 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
10559 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
10562 /* Returns nonzero if things of type FROM can be converted to TO with a
10563 standard conversion. */
10566 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
10568 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
10571 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
10574 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
10575 tsubst_flags_t complain
)
10581 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10582 p
= conversion_obstack_alloc (0);
10583 /* We want to discard any access checks done for this test,
10584 as we might not be in the appropriate access context and
10585 we'll do the check again when we actually perform the
10587 push_deferring_access_checks (dk_deferred
);
10589 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10591 ok_p
= (t
&& !t
->bad_p
);
10593 /* Discard the access checks now. */
10594 pop_deferring_access_checks ();
10595 /* Free all the conversions we allocated. */
10596 obstack_free (&conversion_obstack
, p
);
10601 /* Like can_convert_arg, but allows dubious conversions as well. */
10604 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
10605 tsubst_flags_t complain
)
10610 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10611 p
= conversion_obstack_alloc (0);
10612 /* Try to perform the conversion. */
10613 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10615 /* Free all the conversions we allocated. */
10616 obstack_free (&conversion_obstack
, p
);
10621 /* Convert EXPR to TYPE. Return the converted expression.
10623 Note that we allow bad conversions here because by the time we get to
10624 this point we are committed to doing the conversion. If we end up
10625 doing a bad conversion, convert_like will complain. */
10628 perform_implicit_conversion_flags (tree type
, tree expr
,
10629 tsubst_flags_t complain
, int flags
)
10633 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
10635 if (TREE_CODE (type
) == REFERENCE_TYPE
)
10636 expr
= mark_lvalue_use (expr
);
10638 expr
= mark_rvalue_use (expr
);
10640 if (error_operand_p (expr
))
10641 return error_mark_node
;
10643 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10644 p
= conversion_obstack_alloc (0);
10646 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
10647 /*c_cast_p=*/false,
10652 if (complain
& tf_error
)
10654 /* If expr has unknown type, then it is an overloaded function.
10655 Call instantiate_type to get good error messages. */
10656 if (TREE_TYPE (expr
) == unknown_type_node
)
10657 instantiate_type (type
, expr
, complain
);
10658 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
10659 /* We gave an error. */;
10661 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
10662 TREE_TYPE (expr
), type
);
10664 expr
= error_mark_node
;
10666 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
10668 /* In a template, we are only concerned about determining the
10669 type of non-dependent expressions, so we do not have to
10670 perform the actual conversion. But for initializers, we
10671 need to be able to perform it at instantiation
10672 (or instantiate_non_dependent_expr) time. */
10673 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
10674 if (!(flags
& LOOKUP_ONLYCONVERTING
))
10675 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
10678 expr
= convert_like (conv
, expr
, complain
);
10680 /* Free all the conversions we allocated. */
10681 obstack_free (&conversion_obstack
, p
);
10687 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
10689 return perform_implicit_conversion_flags (type
, expr
, complain
,
10693 /* Convert EXPR to TYPE (as a direct-initialization) if that is
10694 permitted. If the conversion is valid, the converted expression is
10695 returned. Otherwise, NULL_TREE is returned, except in the case
10696 that TYPE is a class type; in that case, an error is issued. If
10697 C_CAST_P is true, then this direct-initialization is taking
10698 place as part of a static_cast being attempted as part of a C-style
10702 perform_direct_initialization_if_possible (tree type
,
10705 tsubst_flags_t complain
)
10710 if (type
== error_mark_node
|| error_operand_p (expr
))
10711 return error_mark_node
;
10714 If the destination type is a (possibly cv-qualified) class type:
10716 -- If the initialization is direct-initialization ...,
10717 constructors are considered. ... If no constructor applies, or
10718 the overload resolution is ambiguous, the initialization is
10720 if (CLASS_TYPE_P (type
))
10722 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
10723 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
10724 &args
, type
, LOOKUP_NORMAL
, complain
);
10725 release_tree_vector (args
);
10726 return build_cplus_new (type
, expr
, complain
);
10729 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10730 p
= conversion_obstack_alloc (0);
10732 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
10734 LOOKUP_NORMAL
, complain
);
10735 if (!conv
|| conv
->bad_p
)
10737 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
10739 /* In a template, we are only concerned about determining the
10740 type of non-dependent expressions, so we do not have to
10741 perform the actual conversion. But for initializers, we
10742 need to be able to perform it at instantiation
10743 (or instantiate_non_dependent_expr) time. */
10744 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
10745 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
10748 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
10749 /*issue_conversion_warnings=*/false,
10753 /* Free all the conversions we allocated. */
10754 obstack_free (&conversion_obstack
, p
);
10759 /* When initializing a reference that lasts longer than a full-expression,
10760 this special rule applies:
10764 The temporary to which the reference is bound or the temporary
10765 that is the complete object to which the reference is bound
10766 persists for the lifetime of the reference.
10768 The temporaries created during the evaluation of the expression
10769 initializing the reference, except the temporary to which the
10770 reference is bound, are destroyed at the end of the
10771 full-expression in which they are created.
10773 In that case, we store the converted expression into a new
10774 VAR_DECL in a new scope.
10776 However, we want to be careful not to create temporaries when
10777 they are not required. For example, given:
10780 struct D : public B {};
10784 there is no need to copy the return value from "f"; we can just
10785 extend its lifetime. Similarly, given:
10788 struct T { operator S(); };
10792 we can extend the lifetime of the return value of the conversion
10795 The next several functions are involved in this lifetime extension. */
10797 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
10798 reference is being bound to a temporary. Create and return a new
10799 VAR_DECL with the indicated TYPE; this variable will store the value to
10800 which the reference is bound. */
10803 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
10805 tree var
= create_temporary_var (type
);
10807 /* Register the variable. */
10809 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
10811 /* Namespace-scope or local static; give it a mangled name. */
10812 /* FIXME share comdat with decl? */
10814 TREE_STATIC (var
) = TREE_STATIC (decl
);
10815 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
10816 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
10818 tree name
= mangle_ref_init_variable (decl
);
10819 DECL_NAME (var
) = name
;
10820 SET_DECL_ASSEMBLER_NAME (var
, name
);
10822 var
= pushdecl (var
);
10825 /* Create a new cleanup level if necessary. */
10826 maybe_push_cleanup_level (type
);
10831 /* EXPR is the initializer for a variable DECL of reference or
10832 std::initializer_list type. Create, push and return a new VAR_DECL
10833 for the initializer so that it will live as long as DECL. Any
10834 cleanup for the new variable is returned through CLEANUP, and the
10835 code to initialize the new variable is returned through INITP. */
10838 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
10845 /* Create the temporary variable. */
10846 type
= TREE_TYPE (expr
);
10847 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
10848 layout_decl (var
, 0);
10849 /* If the rvalue is the result of a function call it will be
10850 a TARGET_EXPR. If it is some other construct (such as a
10851 member access expression where the underlying object is
10852 itself the result of a function call), turn it into a
10853 TARGET_EXPR here. It is important that EXPR be a
10854 TARGET_EXPR below since otherwise the INIT_EXPR will
10855 attempt to make a bitwise copy of EXPR to initialize
10857 if (TREE_CODE (expr
) != TARGET_EXPR
)
10858 expr
= get_target_expr (expr
);
10860 if (TREE_CODE (decl
) == FIELD_DECL
10861 && extra_warnings
&& !TREE_NO_WARNING (decl
))
10863 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
10864 "until the constructor exits", decl
);
10865 TREE_NO_WARNING (decl
) = true;
10868 /* Recursively extend temps in this initializer. */
10869 TARGET_EXPR_INITIAL (expr
)
10870 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
10872 /* Any reference temp has a non-trivial initializer. */
10873 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
10875 /* If the initializer is constant, put it in DECL_INITIAL so we get
10876 static initialization and use in constant expressions. */
10877 init
= maybe_constant_init (expr
);
10878 /* As in store_init_value. */
10879 init
= cp_fully_fold (init
);
10880 if (TREE_CONSTANT (init
))
10882 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
10884 /* 5.19 says that a constant expression can include an
10885 lvalue-rvalue conversion applied to "a glvalue of literal type
10886 that refers to a non-volatile temporary object initialized
10887 with a constant expression". Rather than try to communicate
10888 that this VAR_DECL is a temporary, just mark it constexpr.
10890 Currently this is only useful for initializer_list temporaries,
10891 since reference vars can't appear in constant expressions. */
10892 DECL_DECLARED_CONSTEXPR_P (var
) = true;
10893 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
10894 TREE_CONSTANT (var
) = true;
10896 DECL_INITIAL (var
) = init
;
10900 /* Create the INIT_EXPR that will initialize the temporary
10902 init
= split_nonconstant_init (var
, expr
);
10903 if (at_function_scope_p ())
10905 add_decl_expr (var
);
10907 if (TREE_STATIC (var
))
10908 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
10911 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
10913 vec_safe_push (*cleanups
, cleanup
);
10916 /* We must be careful to destroy the temporary only
10917 after its initialization has taken place. If the
10918 initialization throws an exception, then the
10919 destructor should not be run. We cannot simply
10920 transform INIT into something like:
10922 (INIT, ({ CLEANUP_STMT; }))
10924 because emit_local_var always treats the
10925 initializer as a full-expression. Thus, the
10926 destructor would run too early; it would run at the
10927 end of initializing the reference variable, rather
10928 than at the end of the block enclosing the
10929 reference variable.
10931 The solution is to pass back a cleanup expression
10932 which the caller is responsible for attaching to
10933 the statement tree. */
10937 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
10938 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
10940 if (CP_DECL_THREAD_LOCAL_P (var
))
10941 tls_aggregates
= tree_cons (NULL_TREE
, var
,
10944 static_aggregates
= tree_cons (NULL_TREE
, var
,
10945 static_aggregates
);
10948 /* Check whether the dtor is callable. */
10949 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
10951 /* Avoid -Wunused-variable warning (c++/38958). */
10952 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
10954 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
10960 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
10961 initializing a variable of that TYPE. */
10964 initialize_reference (tree type
, tree expr
,
10965 int flags
, tsubst_flags_t complain
)
10969 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
10971 if (type
== error_mark_node
|| error_operand_p (expr
))
10972 return error_mark_node
;
10974 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10975 p
= conversion_obstack_alloc (0);
10977 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
10979 if (!conv
|| conv
->bad_p
)
10981 if (complain
& tf_error
)
10984 convert_like (conv
, expr
, complain
);
10985 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
10986 && !TYPE_REF_IS_RVALUE (type
)
10987 && !lvalue_p (expr
))
10988 error_at (loc
, "invalid initialization of non-const reference of "
10989 "type %qH from an rvalue of type %qI",
10990 type
, TREE_TYPE (expr
));
10992 error_at (loc
, "invalid initialization of reference of type "
10993 "%qH from expression of type %qI", type
,
10996 return error_mark_node
;
10999 if (conv
->kind
== ck_ref_bind
)
11000 /* Perform the conversion. */
11001 expr
= convert_like (conv
, expr
, complain
);
11002 else if (conv
->kind
== ck_ambig
)
11003 /* We gave an error in build_user_type_conversion_1. */
11004 expr
= error_mark_node
;
11006 gcc_unreachable ();
11008 /* Free all the conversions we allocated. */
11009 obstack_free (&conversion_obstack
, p
);
11014 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11015 which is bound either to a reference or a std::initializer_list. */
11018 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11023 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11025 TREE_OPERAND (sub
, 1)
11026 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11029 if (TREE_CODE (sub
) != ADDR_EXPR
)
11031 /* Deal with binding to a subobject. */
11032 for (p
= &TREE_OPERAND (sub
, 0); TREE_CODE (*p
) == COMPONENT_REF
; )
11033 p
= &TREE_OPERAND (*p
, 0);
11034 if (TREE_CODE (*p
) == TARGET_EXPR
)
11036 tree subinit
= NULL_TREE
;
11037 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11038 recompute_tree_invariant_for_addr_expr (sub
);
11040 init
= fold_convert (TREE_TYPE (init
), sub
);
11042 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11047 /* INIT is part of the initializer for DECL. If there are any
11048 reference or initializer lists being initialized, extend their
11049 lifetime to match that of DECL. */
11052 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11054 tree type
= TREE_TYPE (init
);
11055 if (processing_template_decl
)
11057 if (TREE_CODE (type
) == REFERENCE_TYPE
)
11058 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11062 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11063 ctor
= TARGET_EXPR_INITIAL (ctor
);
11064 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11066 if (is_std_init_list (type
))
11068 /* The temporary array underlying a std::initializer_list
11069 is handled like a reference temporary. */
11070 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11071 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11072 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11077 constructor_elt
*p
;
11078 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11079 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11080 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11082 recompute_constructor_flags (ctor
);
11083 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11084 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11091 /* Returns true iff an initializer for TYPE could contain temporaries that
11092 need to be extended because they are bound to references or
11093 std::initializer_list. */
11096 type_has_extended_temps (tree type
)
11098 type
= strip_array_types (type
);
11099 if (TREE_CODE (type
) == REFERENCE_TYPE
)
11101 if (CLASS_TYPE_P (type
))
11103 if (is_std_init_list (type
))
11105 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11106 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11107 if (type_has_extended_temps (TREE_TYPE (f
)))
11113 /* Returns true iff TYPE is some variant of std::initializer_list. */
11116 is_std_init_list (tree type
)
11118 if (!TYPE_P (type
))
11120 if (cxx_dialect
== cxx98
)
11122 /* Look through typedefs. */
11123 type
= TYPE_MAIN_VARIANT (type
);
11124 return (CLASS_TYPE_P (type
)
11125 && CP_TYPE_CONTEXT (type
) == std_node
11126 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11129 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11130 will accept an argument list of a single std::initializer_list<T>. */
11133 is_list_ctor (tree decl
)
11135 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11138 if (!args
|| args
== void_list_node
)
11141 arg
= non_reference (TREE_VALUE (args
));
11142 if (!is_std_init_list (arg
))
11145 args
= TREE_CHAIN (args
);
11147 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11148 /* There are more non-defaulted parms. */
11154 #include "gt-cp-call.h"