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, so until the committee resolves core
3278 issue 2189, let's disable this candidate if there are any viable call
3280 if (any_strictly_viable (*candidates
))
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 /* Replace the identity conversion with the user conversion
3652 /* Handle overload resolution for initializing an object of class type from
3653 an initializer list. First we look for a suitable constructor that
3654 takes a std::initializer_list; if we don't find one, we then look for a
3655 non-list constructor.
3657 Parameters are as for add_candidates, except that the arguments are in
3658 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3659 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3662 add_list_candidates (tree fns
, tree first_arg
,
3663 const vec
<tree
, va_gc
> *args
, tree totype
,
3664 tree explicit_targs
, bool template_only
,
3665 tree conversion_path
, tree access_path
,
3667 struct z_candidate
**candidates
,
3668 tsubst_flags_t complain
)
3670 gcc_assert (*candidates
== NULL
);
3672 /* We're looking for a ctor for list-initialization. */
3673 flags
|= LOOKUP_LIST_INIT_CTOR
;
3674 /* And we don't allow narrowing conversions. We also use this flag to
3675 avoid the copy constructor call for copy-list-initialization. */
3676 flags
|= LOOKUP_NO_NARROWING
;
3678 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3679 tree init_list
= (*args
)[nart
];
3681 /* Always use the default constructor if the list is empty (DR 990). */
3682 if (CONSTRUCTOR_NELTS (init_list
) == 0
3683 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3685 /* If the class has a list ctor, try passing the list as a single
3686 argument first, but only consider list ctors. */
3687 else if (TYPE_HAS_LIST_CTOR (totype
))
3689 flags
|= LOOKUP_LIST_ONLY
;
3690 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3691 explicit_targs
, template_only
, conversion_path
,
3692 access_path
, flags
, candidates
, complain
);
3693 if (any_strictly_viable (*candidates
))
3697 /* Expand the CONSTRUCTOR into a new argument vec. */
3698 vec
<tree
, va_gc
> *new_args
;
3699 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3700 for (unsigned i
= 0; i
< nart
; ++i
)
3701 new_args
->quick_push ((*args
)[i
]);
3702 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3703 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3705 /* We aren't looking for list-ctors anymore. */
3706 flags
&= ~LOOKUP_LIST_ONLY
;
3707 /* We allow more user-defined conversions within an init-list. */
3708 flags
&= ~LOOKUP_NO_CONVERSION
;
3710 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3711 explicit_targs
, template_only
, conversion_path
,
3712 access_path
, flags
, candidates
, complain
);
3715 /* Returns the best overload candidate to perform the requested
3716 conversion. This function is used for three the overloading situations
3717 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3718 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3719 per [dcl.init.ref], so we ignore temporary bindings. */
3721 static struct z_candidate
*
3722 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3723 tsubst_flags_t complain
)
3725 struct z_candidate
*candidates
, *cand
;
3727 tree ctors
= NULL_TREE
;
3728 tree conv_fns
= NULL_TREE
;
3729 conversion
*conv
= NULL
;
3730 tree first_arg
= NULL_TREE
;
3731 vec
<tree
, va_gc
> *args
= NULL
;
3738 fromtype
= TREE_TYPE (expr
);
3740 /* We represent conversion within a hierarchy using RVALUE_CONV and
3741 BASE_CONV, as specified by [over.best.ics]; these become plain
3742 constructor calls, as specified in [dcl.init]. */
3743 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3744 || !DERIVED_FROM_P (totype
, fromtype
));
3746 if (CLASS_TYPE_P (totype
))
3747 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3748 creating a garbage BASELINK; constructors can't be inherited. */
3749 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3751 if (MAYBE_CLASS_TYPE_P (fromtype
))
3753 tree to_nonref
= non_reference (totype
);
3754 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3755 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3756 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3758 /* [class.conv.fct] A conversion function is never used to
3759 convert a (possibly cv-qualified) object to the (possibly
3760 cv-qualified) same object type (or a reference to it), to a
3761 (possibly cv-qualified) base class of that type (or a
3762 reference to it)... */
3765 conv_fns
= lookup_conversions (fromtype
);
3769 flags
|= LOOKUP_NO_CONVERSION
;
3770 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3771 flags
|= LOOKUP_NO_NARROWING
;
3773 /* It's OK to bind a temporary for converting constructor arguments, but
3774 not in converting the return value of a conversion operator. */
3775 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3776 | (flags
& LOOKUP_NO_NARROWING
));
3777 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3781 int ctorflags
= flags
;
3783 first_arg
= build_dummy_object (totype
);
3785 /* We should never try to call the abstract or base constructor
3787 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3788 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3790 args
= make_tree_vector_single (expr
);
3791 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3793 /* List-initialization. */
3794 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3795 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3796 ctorflags
, &candidates
, complain
);
3800 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3801 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3802 ctorflags
, &candidates
, complain
);
3805 for (cand
= candidates
; cand
; cand
= cand
->next
)
3807 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3809 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3810 set, then this is copy-initialization. In that case, "The
3811 result of the call is then used to direct-initialize the
3812 object that is the destination of the copy-initialization."
3815 We represent this in the conversion sequence with an
3816 rvalue conversion, which means a constructor call. */
3817 if (TREE_CODE (totype
) != REFERENCE_TYPE
3818 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3820 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3826 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3827 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3832 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3834 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3835 struct z_candidate
*old_candidates
;
3837 /* If we are called to convert to a reference type, we are trying to
3838 find a direct binding, so don't even consider temporaries. If
3839 we don't find a direct binding, the caller will try again to
3840 look for a temporary binding. */
3841 if (TREE_CODE (totype
) == REFERENCE_TYPE
)
3842 convflags
|= LOOKUP_NO_TEMP_BIND
;
3844 old_candidates
= candidates
;
3845 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3847 conversion_path
, TYPE_BINFO (fromtype
),
3848 flags
, &candidates
, complain
);
3850 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
3852 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
3854 = implicit_conversion (totype
,
3857 /*c_cast_p=*/false, convflags
,
3860 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3861 copy-initialization. In that case, "The result of the
3862 call is then used to direct-initialize the object that is
3863 the destination of the copy-initialization." [dcl.init]
3865 We represent this in the conversion sequence with an
3866 rvalue conversion, which means a constructor call. But
3867 don't add a second rvalue conversion if there's already
3868 one there. Which there really shouldn't be, but it's
3869 harmless since we'd add it here anyway. */
3870 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
3871 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3872 ics
= build_conv (ck_rvalue
, totype
, ics
);
3874 cand
->second_conv
= ics
;
3879 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
3882 else if (DECL_NONCONVERTING_P (cand
->fn
)
3883 && ics
->rank
> cr_exact
)
3885 /* 13.3.1.5: For direct-initialization, those explicit
3886 conversion functions that are not hidden within S and
3887 yield type T or a type that can be converted to type T
3888 with a qualification conversion (4.4) are also candidate
3890 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3891 I've raised this issue with the committee. --jason 9/2011 */
3893 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
3895 else if (cand
->viable
== 1 && ics
->bad_p
)
3899 = bad_arg_conversion_rejection (NULL_TREE
, -2,
3902 else if (primary_template_specialization_p (cand
->fn
)
3903 && ics
->rank
> cr_exact
)
3905 /* 13.3.3.1.2: If the user-defined conversion is specified by
3906 a specialization of a conversion function template, the
3907 second standard conversion sequence shall have exact match
3910 cand
->reason
= template_conversion_rejection (rettype
, totype
);
3915 candidates
= splice_viable (candidates
, false, &any_viable_p
);
3919 release_tree_vector (args
);
3923 cand
= tourney (candidates
, complain
);
3926 if (complain
& tf_error
)
3928 error ("conversion from %qH to %qI is ambiguous",
3930 print_z_candidates (location_of (expr
), candidates
);
3933 cand
= candidates
; /* any one will do */
3934 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
3935 cand
->second_conv
->user_conv_p
= true;
3936 if (!any_strictly_viable (candidates
))
3937 cand
->second_conv
->bad_p
= true;
3938 if (flags
& LOOKUP_ONLYCONVERTING
)
3939 cand
->second_conv
->need_temporary_p
= true;
3940 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3941 ambiguous conversion is no worse than another user-defined
3948 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
3949 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
3950 else if (cand
->second_conv
->kind
== ck_rvalue
)
3951 /* DR 5: [in the first step of copy-initialization]...if the function
3952 is a constructor, the call initializes a temporary of the
3953 cv-unqualified version of the destination type. */
3954 convtype
= cv_unqualified (totype
);
3957 /* Build the user conversion sequence. */
3961 build_identity_conv (TREE_TYPE (expr
), expr
));
3963 if (cand
->viable
== -1)
3966 /* Remember that this was a list-initialization. */
3967 if (flags
& LOOKUP_NO_NARROWING
)
3968 conv
->check_narrowing
= true;
3970 /* Combine it with the second conversion sequence. */
3971 cand
->second_conv
= merge_conversion_sequences (conv
,
3977 /* Wrapper for above. */
3980 build_user_type_conversion (tree totype
, tree expr
, int flags
,
3981 tsubst_flags_t complain
)
3983 struct z_candidate
*cand
;
3986 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
3987 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
3991 if (cand
->second_conv
->kind
== ck_ambig
)
3992 ret
= error_mark_node
;
3995 expr
= convert_like (cand
->second_conv
, expr
, complain
);
3996 ret
= convert_from_reference (expr
);
4002 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4006 /* Subroutine of convert_nontype_argument.
4008 EXPR is an expression used in a context that requires a converted
4009 constant-expression, such as a template non-type parameter. Do any
4010 necessary conversions (that are permitted for converted
4011 constant-expressions) to convert it to the desired type.
4013 If conversion is successful, returns the converted expression;
4014 otherwise, returns error_mark_node. */
4017 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4022 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
4024 if (error_operand_p (expr
))
4025 return error_mark_node
;
4027 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4028 p
= conversion_obstack_alloc (0);
4030 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4032 LOOKUP_IMPLICIT
, complain
);
4034 /* A converted constant expression of type T is an expression, implicitly
4035 converted to type T, where the converted expression is a constant
4036 expression and the implicit conversion sequence contains only
4038 * user-defined conversions,
4039 * lvalue-to-rvalue conversions (7.1),
4040 * array-to-pointer conversions (7.2),
4041 * function-to-pointer conversions (7.3),
4042 * qualification conversions (7.5),
4043 * integral promotions (7.6),
4044 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4045 * null pointer conversions (7.11) from std::nullptr_t,
4046 * null member pointer conversions (7.12) from std::nullptr_t, and
4047 * function pointer conversions (7.13),
4049 and where the reference binding (if any) binds directly. */
4051 for (conversion
*c
= conv
;
4052 conv
&& c
->kind
!= ck_identity
;
4053 c
= next_conversion (c
))
4057 /* A conversion function is OK. If it isn't constexpr, we'll
4058 complain later that the argument isn't constant. */
4060 /* The lvalue-to-rvalue conversion is OK. */
4062 /* Array-to-pointer and function-to-pointer. */
4064 /* Function pointer conversions. */
4066 /* Qualification conversions. */
4071 if (c
->need_temporary_p
)
4073 if (complain
& tf_error
)
4074 error_at (loc
, "initializing %qH with %qI in converted "
4075 "constant expression does not bind directly",
4076 type
, next_conversion (c
)->type
);
4085 t
= next_conversion (c
)->type
;
4086 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4087 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4088 /* Integral promotion or conversion. */
4090 if (NULLPTR_TYPE_P (t
))
4091 /* Conversion from nullptr to pointer or pointer-to-member. */
4094 if (complain
& tf_error
)
4095 error_at (loc
, "conversion from %qH to %qI in a "
4096 "converted constant expression", t
, type
);
4105 /* Avoid confusing convert_nontype_argument by introducing
4106 a redundant conversion to the same reference type. */
4107 if (conv
&& conv
->kind
== ck_ref_bind
4108 && REFERENCE_REF_P (expr
))
4110 tree ref
= TREE_OPERAND (expr
, 0);
4111 if (same_type_p (type
, TREE_TYPE (ref
)))
4116 expr
= convert_like (conv
, expr
, complain
);
4118 expr
= error_mark_node
;
4120 /* Free all the conversions we allocated. */
4121 obstack_free (&conversion_obstack
, p
);
4126 /* Do any initial processing on the arguments to a function call. */
4128 static vec
<tree
, va_gc
> *
4129 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4134 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4136 if (error_operand_p (arg
))
4138 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4140 if (complain
& tf_error
)
4141 error ("invalid use of void expression");
4144 else if (invalid_nonstatic_memfn_p (input_location
, arg
, complain
))
4150 /* Perform overload resolution on FN, which is called with the ARGS.
4152 Return the candidate function selected by overload resolution, or
4153 NULL if the event that overload resolution failed. In the case
4154 that overload resolution fails, *CANDIDATES will be the set of
4155 candidates considered, and ANY_VIABLE_P will be set to true or
4156 false to indicate whether or not any of the candidates were
4159 The ARGS should already have gone through RESOLVE_ARGS before this
4160 function is called. */
4162 static struct z_candidate
*
4163 perform_overload_resolution (tree fn
,
4164 const vec
<tree
, va_gc
> *args
,
4165 struct z_candidate
**candidates
,
4166 bool *any_viable_p
, tsubst_flags_t complain
)
4168 struct z_candidate
*cand
;
4169 tree explicit_targs
;
4172 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4174 explicit_targs
= NULL_TREE
;
4178 *any_viable_p
= true;
4181 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4182 || TREE_CODE (fn
) == TEMPLATE_DECL
4183 || TREE_CODE (fn
) == OVERLOAD
4184 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4186 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4188 explicit_targs
= TREE_OPERAND (fn
, 1);
4189 fn
= TREE_OPERAND (fn
, 0);
4193 /* Add the various candidate functions. */
4194 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4195 explicit_targs
, template_only
,
4196 /*conversion_path=*/NULL_TREE
,
4197 /*access_path=*/NULL_TREE
,
4199 candidates
, complain
);
4201 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4203 cand
= tourney (*candidates
, complain
);
4207 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4211 /* Print an error message about being unable to build a call to FN with
4212 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4213 be located; CANDIDATES is a possibly empty list of such
4217 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4218 struct z_candidate
*candidates
)
4220 tree targs
= NULL_TREE
;
4221 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4223 targs
= TREE_OPERAND (fn
, 1);
4224 fn
= TREE_OPERAND (fn
, 0);
4226 tree name
= OVL_NAME (fn
);
4227 location_t loc
= location_of (name
);
4229 name
= lookup_template_function (name
, targs
);
4231 if (!any_strictly_viable (candidates
))
4232 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4233 name
, build_tree_list_vec (args
));
4235 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4236 name
, build_tree_list_vec (args
));
4238 print_z_candidates (loc
, candidates
);
4241 /* Return an expression for a call to FN (a namespace-scope function,
4242 or a static member function) with the ARGS. This may change
4246 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4247 tsubst_flags_t complain
)
4249 struct z_candidate
*candidates
, *cand
;
4254 if (args
!= NULL
&& *args
!= NULL
)
4256 *args
= resolve_args (*args
, complain
);
4258 return error_mark_node
;
4262 tm_malloc_replacement (fn
);
4264 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4265 p
= conversion_obstack_alloc (0);
4267 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4272 if (complain
& tf_error
)
4274 // If there is a single (non-viable) function candidate,
4275 // let the error be diagnosed by cp_build_function_call_vec.
4276 if (!any_viable_p
&& candidates
&& ! candidates
->next
4277 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4278 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4280 // Otherwise, emit notes for non-viable candidates.
4281 print_error_for_call_failure (fn
, *args
, candidates
);
4283 result
= error_mark_node
;
4287 int flags
= LOOKUP_NORMAL
;
4288 /* If fn is template_id_expr, the call has explicit template arguments
4289 (e.g. func<int>(5)), communicate this info to build_over_call
4290 through flags so that later we can use it to decide whether to warn
4291 about peculiar null pointer conversion. */
4292 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4294 /* If overload resolution selects a specialization of a
4295 function concept for non-dependent template arguments,
4296 the expression is true if the constraints are satisfied
4297 and false otherwise.
4299 NOTE: This is an extension of Concepts Lite TS that
4300 allows constraints to be used in expressions. */
4301 if (flag_concepts
&& !processing_template_decl
)
4303 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4304 tree targs
= DECL_TI_ARGS (cand
->fn
);
4305 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4306 if (DECL_DECLARED_CONCEPT_P (decl
))
4307 return evaluate_function_concept (decl
, targs
);
4310 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4313 result
= build_over_call (cand
, flags
, complain
);
4316 /* Free all the conversions we allocated. */
4317 obstack_free (&conversion_obstack
, p
);
4322 /* Build a call to a global operator new. FNNAME is the name of the
4323 operator (either "operator new" or "operator new[]") and ARGS are
4324 the arguments provided. This may change ARGS. *SIZE points to the
4325 total number of bytes required by the allocation, and is updated if
4326 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4327 be used. If this function determines that no cookie should be
4328 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4329 is not NULL_TREE, it is evaluated before calculating the final
4330 array size, and if it fails, the array size is replaced with
4331 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4332 is non-NULL, it will be set, upon return, to the allocation
4336 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4337 tree
*size
, tree
*cookie_size
,
4338 tree align_arg
, tree size_check
,
4339 tree
*fn
, tsubst_flags_t complain
)
4341 tree original_size
= *size
;
4343 struct z_candidate
*candidates
;
4344 struct z_candidate
*cand
= NULL
;
4349 /* Set to (size_t)-1 if the size check fails. */
4350 if (size_check
!= NULL_TREE
)
4352 tree errval
= TYPE_MAX_VALUE (sizetype
);
4353 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4354 errval
= throw_bad_array_new_length ();
4355 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4356 original_size
, errval
);
4358 vec_safe_insert (*args
, 0, *size
);
4359 *args
= resolve_args (*args
, complain
);
4361 return error_mark_node
;
4367 If this lookup fails to find the name, or if the allocated type
4368 is not a class type, the allocation function's name is looked
4369 up in the global scope.
4371 we disregard block-scope declarations of "operator new". */
4372 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4373 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4377 vec
<tree
, va_gc
>* align_args
4378 = vec_copy_and_insert (*args
, align_arg
, 1);
4379 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4380 &any_viable_p
, tf_none
);
4383 /* If no aligned allocation function matches, try again without the
4387 /* Figure out what function is being called. */
4389 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4392 /* If no suitable function could be found, issue an error message
4396 if (complain
& tf_error
)
4397 print_error_for_call_failure (fns
, *args
, candidates
);
4398 return error_mark_node
;
4401 /* If a cookie is required, add some extra space. Whether
4402 or not a cookie is required cannot be determined until
4403 after we know which function was called. */
4406 bool use_cookie
= true;
4409 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4410 /* Skip the size_t parameter. */
4411 arg_types
= TREE_CHAIN (arg_types
);
4412 /* Check the remaining parameters (if any). */
4414 && TREE_CHAIN (arg_types
) == void_list_node
4415 && same_type_p (TREE_VALUE (arg_types
),
4418 /* If we need a cookie, adjust the number of bytes allocated. */
4421 /* Update the total size. */
4422 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4425 /* Set to (size_t)-1 if the size check fails. */
4426 gcc_assert (size_check
!= NULL_TREE
);
4427 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4428 *size
, TYPE_MAX_VALUE (sizetype
));
4430 /* Update the argument list to reflect the adjusted size. */
4431 (**args
)[0] = *size
;
4434 *cookie_size
= NULL_TREE
;
4437 /* Tell our caller which function we decided to call. */
4441 /* Build the CALL_EXPR. */
4442 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4445 /* Build a new call to operator(). This may change ARGS. */
4448 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4450 struct z_candidate
*candidates
= 0, *cand
;
4451 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4453 tree result
= NULL_TREE
;
4456 obj
= mark_lvalue_use (obj
);
4458 if (error_operand_p (obj
))
4459 return error_mark_node
;
4461 tree type
= TREE_TYPE (obj
);
4463 obj
= prep_operand (obj
);
4465 if (TYPE_PTRMEMFUNC_P (type
))
4467 if (complain
& tf_error
)
4468 /* It's no good looking for an overloaded operator() on a
4469 pointer-to-member-function. */
4470 error ("pointer-to-member function %qE cannot be called without "
4471 "an object; consider using %<.*%> or %<->*%>", obj
);
4472 return error_mark_node
;
4475 if (TYPE_BINFO (type
))
4477 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4478 if (fns
== error_mark_node
)
4479 return error_mark_node
;
4484 if (args
!= NULL
&& *args
!= NULL
)
4486 *args
= resolve_args (*args
, complain
);
4488 return error_mark_node
;
4491 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4492 p
= conversion_obstack_alloc (0);
4496 first_mem_arg
= obj
;
4498 add_candidates (BASELINK_FUNCTIONS (fns
),
4499 first_mem_arg
, *args
, NULL_TREE
,
4501 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4502 LOOKUP_NORMAL
, &candidates
, complain
);
4505 convs
= lookup_conversions (type
);
4507 for (; convs
; convs
= TREE_CHAIN (convs
))
4509 tree totype
= TREE_TYPE (convs
);
4511 if (TYPE_PTRFN_P (totype
)
4512 || TYPE_REFFN_P (totype
)
4513 || (TREE_CODE (totype
) == REFERENCE_TYPE
4514 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4515 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4519 if (DECL_NONCONVERTING_P (fn
))
4522 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4523 add_template_conv_candidate
4524 (&candidates
, fn
, obj
, *args
, totype
,
4525 /*access_path=*/NULL_TREE
,
4526 /*conversion_path=*/NULL_TREE
, complain
);
4528 add_conv_candidate (&candidates
, fn
, obj
,
4529 *args
, /*conversion_path=*/NULL_TREE
,
4530 /*access_path=*/NULL_TREE
, complain
);
4534 /* Be strict here because if we choose a bad conversion candidate, the
4535 errors we get won't mention the call context. */
4536 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4539 if (complain
& tf_error
)
4541 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4542 build_tree_list_vec (*args
));
4543 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4545 result
= error_mark_node
;
4549 cand
= tourney (candidates
, complain
);
4552 if (complain
& tf_error
)
4554 error ("call of %<(%T) (%A)%> is ambiguous",
4555 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4556 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4558 result
= error_mark_node
;
4560 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4561 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4562 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4563 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4566 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4567 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4571 gcc_checking_assert (TYPE_P (cand
->fn
));
4572 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4574 obj
= convert_from_reference (obj
);
4575 result
= cp_build_function_call_vec (obj
, args
, complain
);
4579 /* Free all the conversions we allocated. */
4580 obstack_free (&conversion_obstack
, p
);
4585 /* Wrapper for above. */
4588 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4591 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4592 ret
= build_op_call_1 (obj
, args
, complain
);
4593 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4597 /* Called by op_error to prepare format strings suitable for the error
4598 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4599 and a suffix (controlled by NTYPES). */
4602 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4606 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4607 : G_("no match for "), errmsg
, NULL
);
4610 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4611 else if (ntypes
== 2)
4612 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4614 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4620 op_error (location_t loc
, enum tree_code code
, enum tree_code code2
,
4621 tree arg1
, tree arg2
, tree arg3
, bool match
)
4623 bool assop
= code
== MODIFY_EXPR
;
4624 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4629 if (flag_diagnostics_show_caret
)
4630 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4632 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4634 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4635 "in %<%E ? %E : %E%>"), 3, match
),
4637 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4640 case POSTINCREMENT_EXPR
:
4641 case POSTDECREMENT_EXPR
:
4642 if (flag_diagnostics_show_caret
)
4643 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4644 opname
, TREE_TYPE (arg1
));
4646 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4648 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4652 if (flag_diagnostics_show_caret
)
4653 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4654 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4656 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4658 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4663 if (flag_diagnostics_show_caret
)
4664 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4665 opname
, TREE_TYPE (arg1
));
4667 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4668 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4673 if (flag_diagnostics_show_caret
)
4674 error_at (loc
, op_error_string (G_("%<operator%s%>"), 2, match
),
4675 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4677 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4679 opname
, arg1
, opname
, arg2
,
4680 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4682 if (flag_diagnostics_show_caret
)
4683 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4684 opname
, TREE_TYPE (arg1
));
4686 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4688 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4693 /* Return the implicit conversion sequence that could be used to
4694 convert E1 to E2 in [expr.cond]. */
4697 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4699 tree t1
= non_reference (TREE_TYPE (e1
));
4700 tree t2
= non_reference (TREE_TYPE (e2
));
4706 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4707 implicitly converted (clause _conv_) to the type "lvalue reference to
4708 T2", subject to the constraint that in the conversion the
4709 reference must bind directly (_dcl.init.ref_) to an lvalue.
4711 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4712 implicitly converted to the type "rvalue reference to T2", subject to
4713 the constraint that the reference must bind directly. */
4716 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4717 conv
= implicit_conversion (rtype
,
4721 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4722 |LOOKUP_ONLYCONVERTING
,
4724 if (conv
&& !conv
->bad_p
)
4728 /* If E2 is a prvalue or if neither of the conversions above can be done
4729 and at least one of the operands has (possibly cv-qualified) class
4731 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4736 If E1 and E2 have class type, and the underlying class types are
4737 the same or one is a base class of the other: E1 can be converted
4738 to match E2 if the class of T2 is the same type as, or a base
4739 class of, the class of T1, and the cv-qualification of T2 is the
4740 same cv-qualification as, or a greater cv-qualification than, the
4741 cv-qualification of T1. If the conversion is applied, E1 is
4742 changed to an rvalue of type T2 that still refers to the original
4743 source class object (or the appropriate subobject thereof). */
4744 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4745 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4747 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4749 conv
= build_identity_conv (t1
, e1
);
4750 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4751 TYPE_MAIN_VARIANT (t2
)))
4752 conv
= build_conv (ck_base
, t2
, conv
);
4754 conv
= build_conv (ck_rvalue
, t2
, conv
);
4763 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4764 converted to the type that expression E2 would have if E2 were
4765 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4766 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4767 LOOKUP_IMPLICIT
, complain
);
4770 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4771 arguments to the conditional expression. */
4774 build_conditional_expr_1 (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
4775 tsubst_flags_t complain
)
4779 tree result
= NULL_TREE
;
4780 tree result_type
= NULL_TREE
;
4781 bool is_glvalue
= true;
4782 struct z_candidate
*candidates
= 0;
4783 struct z_candidate
*cand
;
4785 tree orig_arg2
, orig_arg3
;
4787 /* As a G++ extension, the second argument to the conditional can be
4788 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4789 c'.) If the second operand is omitted, make sure it is
4790 calculated only once. */
4793 if (complain
& tf_error
)
4794 pedwarn (loc
, OPT_Wpedantic
,
4795 "ISO C++ forbids omitting the middle term of a ?: expression");
4797 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
4798 warn_for_omitted_condop (loc
, arg1
);
4800 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4801 if (lvalue_p (arg1
))
4802 arg2
= arg1
= cp_stabilize_reference (arg1
);
4804 arg2
= arg1
= cp_save_expr (arg1
);
4807 /* If something has already gone wrong, just pass that fact up the
4809 if (error_operand_p (arg1
)
4810 || error_operand_p (arg2
)
4811 || error_operand_p (arg3
))
4812 return error_mark_node
;
4817 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
4819 tree arg1_type
= TREE_TYPE (arg1
);
4821 /* If arg1 is another cond_expr choosing between -1 and 0,
4822 then we can use its comparison. It may help to avoid
4823 additional comparison, produce more accurate diagnostics
4824 and enables folding. */
4825 if (TREE_CODE (arg1
) == VEC_COND_EXPR
4826 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
4827 && integer_zerop (TREE_OPERAND (arg1
, 2)))
4828 arg1
= TREE_OPERAND (arg1
, 0);
4830 arg1
= force_rvalue (arg1
, complain
);
4831 arg2
= force_rvalue (arg2
, complain
);
4832 arg3
= force_rvalue (arg3
, complain
);
4834 /* force_rvalue can return error_mark on valid arguments. */
4835 if (error_operand_p (arg1
)
4836 || error_operand_p (arg2
)
4837 || error_operand_p (arg3
))
4838 return error_mark_node
;
4840 arg2_type
= TREE_TYPE (arg2
);
4841 arg3_type
= TREE_TYPE (arg3
);
4843 if (!VECTOR_TYPE_P (arg2_type
)
4844 && !VECTOR_TYPE_P (arg3_type
))
4846 /* Rely on the error messages of the scalar version. */
4847 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
4848 orig_arg2
, orig_arg3
, complain
);
4849 if (scal
== error_mark_node
)
4850 return error_mark_node
;
4851 tree stype
= TREE_TYPE (scal
);
4852 tree ctype
= TREE_TYPE (arg1_type
);
4853 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
4854 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
4856 if (complain
& tf_error
)
4857 error_at (loc
, "inferred scalar type %qT is not an integer or "
4858 "floating point type of the same size as %qT", stype
,
4859 COMPARISON_CLASS_P (arg1
)
4860 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
4862 return error_mark_node
;
4865 tree vtype
= build_opaque_vector_type (stype
,
4866 TYPE_VECTOR_SUBPARTS (arg1_type
));
4867 /* We could pass complain & tf_warning to unsafe_conversion_p,
4868 but the warnings (like Wsign-conversion) have already been
4869 given by the scalar build_conditional_expr_1. We still check
4870 unsafe_conversion_p to forbid truncating long long -> float. */
4871 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
4873 if (complain
& tf_error
)
4874 error_at (loc
, "conversion of scalar %qH to vector %qI "
4875 "involves truncation", arg2_type
, vtype
);
4876 return error_mark_node
;
4878 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
4880 if (complain
& tf_error
)
4881 error_at (loc
, "conversion of scalar %qH to vector %qI "
4882 "involves truncation", arg3_type
, vtype
);
4883 return error_mark_node
;
4886 arg2
= cp_convert (stype
, arg2
, complain
);
4887 arg2
= save_expr (arg2
);
4888 arg2
= build_vector_from_val (vtype
, arg2
);
4890 arg3
= cp_convert (stype
, arg3
, complain
);
4891 arg3
= save_expr (arg3
);
4892 arg3
= build_vector_from_val (vtype
, arg3
);
4896 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
4898 enum stv_conv convert_flag
=
4899 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
4900 complain
& tf_error
);
4902 switch (convert_flag
)
4905 return error_mark_node
;
4908 arg2
= save_expr (arg2
);
4909 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
4910 arg2
= build_vector_from_val (arg3_type
, arg2
);
4911 arg2_type
= TREE_TYPE (arg2
);
4916 arg3
= save_expr (arg3
);
4917 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
4918 arg3
= build_vector_from_val (arg2_type
, arg3
);
4919 arg3_type
= TREE_TYPE (arg3
);
4927 if (!same_type_p (arg2_type
, arg3_type
)
4928 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
4929 TYPE_VECTOR_SUBPARTS (arg2_type
))
4930 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
4932 if (complain
& tf_error
)
4934 "incompatible vector types in conditional expression: "
4935 "%qT, %qT and %qT", TREE_TYPE (arg1
),
4936 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
4937 return error_mark_node
;
4940 if (!COMPARISON_CLASS_P (arg1
))
4942 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
4943 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
4945 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
4950 The first expression is implicitly converted to bool (clause
4952 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
4954 if (error_operand_p (arg1
))
4955 return error_mark_node
;
4959 If either the second or the third operand has type (possibly
4960 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4961 array-to-pointer (_conv.array_), and function-to-pointer
4962 (_conv.func_) standard conversions are performed on the second
4963 and third operands. */
4964 arg2_type
= unlowered_expr_type (arg2
);
4965 arg3_type
= unlowered_expr_type (arg3
);
4966 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
4968 /* Do the conversions. We don't these for `void' type arguments
4969 since it can't have any effect and since decay_conversion
4970 does not handle that case gracefully. */
4971 if (!VOID_TYPE_P (arg2_type
))
4972 arg2
= decay_conversion (arg2
, complain
);
4973 if (!VOID_TYPE_P (arg3_type
))
4974 arg3
= decay_conversion (arg3
, complain
);
4975 arg2_type
= TREE_TYPE (arg2
);
4976 arg3_type
= TREE_TYPE (arg3
);
4980 One of the following shall hold:
4982 --The second or the third operand (but not both) is a
4983 throw-expression (_except.throw_); the result is of the
4984 type of the other and is an rvalue.
4986 --Both the second and the third operands have type void; the
4987 result is of type void and is an rvalue.
4989 We must avoid calling force_rvalue for expressions of type
4990 "void" because it will complain that their value is being
4992 if (TREE_CODE (arg2
) == THROW_EXPR
4993 && TREE_CODE (arg3
) != THROW_EXPR
)
4995 if (!VOID_TYPE_P (arg3_type
))
4997 arg3
= force_rvalue (arg3
, complain
);
4998 if (arg3
== error_mark_node
)
4999 return error_mark_node
;
5001 arg3_type
= TREE_TYPE (arg3
);
5002 result_type
= arg3_type
;
5004 else if (TREE_CODE (arg2
) != THROW_EXPR
5005 && TREE_CODE (arg3
) == THROW_EXPR
)
5007 if (!VOID_TYPE_P (arg2_type
))
5009 arg2
= force_rvalue (arg2
, complain
);
5010 if (arg2
== error_mark_node
)
5011 return error_mark_node
;
5013 arg2_type
= TREE_TYPE (arg2
);
5014 result_type
= arg2_type
;
5016 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5017 result_type
= void_type_node
;
5020 if (complain
& tf_error
)
5022 if (VOID_TYPE_P (arg2_type
))
5023 error_at (EXPR_LOC_OR_LOC (arg3
, loc
),
5024 "second operand to the conditional operator "
5025 "is of type %<void%>, but the third operand is "
5026 "neither a throw-expression nor of type %<void%>");
5028 error_at (EXPR_LOC_OR_LOC (arg2
, loc
),
5029 "third operand to the conditional operator "
5030 "is of type %<void%>, but the second operand is "
5031 "neither a throw-expression nor of type %<void%>");
5033 return error_mark_node
;
5037 goto valid_operands
;
5041 Otherwise, if the second and third operand have different types,
5042 and either has (possibly cv-qualified) class type, or if both are
5043 glvalues of the same value category and the same type except for
5044 cv-qualification, an attempt is made to convert each of those operands
5045 to the type of the other. */
5046 else if (!same_type_p (arg2_type
, arg3_type
)
5047 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5048 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5050 && glvalue_p (arg2
) && glvalue_p (arg3
)
5051 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5055 bool converted
= false;
5057 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5058 p
= conversion_obstack_alloc (0);
5060 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5061 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5065 If both can be converted, or one can be converted but the
5066 conversion is ambiguous, the program is ill-formed. If
5067 neither can be converted, the operands are left unchanged and
5068 further checking is performed as described below. If exactly
5069 one conversion is possible, that conversion is applied to the
5070 chosen operand and the converted operand is used in place of
5071 the original operand for the remainder of this section. */
5072 if ((conv2
&& !conv2
->bad_p
5073 && conv3
&& !conv3
->bad_p
)
5074 || (conv2
&& conv2
->kind
== ck_ambig
)
5075 || (conv3
&& conv3
->kind
== ck_ambig
))
5077 if (complain
& tf_error
)
5079 error_at (loc
, "operands to ?: have different types %qT and %qT",
5080 arg2_type
, arg3_type
);
5081 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5082 inform (loc
, " and each type can be converted to the other");
5083 else if (conv2
&& conv2
->kind
== ck_ambig
)
5084 convert_like (conv2
, arg2
, complain
);
5086 convert_like (conv3
, arg3
, complain
);
5088 result
= error_mark_node
;
5090 else if (conv2
&& !conv2
->bad_p
)
5092 arg2
= convert_like (conv2
, arg2
, complain
);
5093 arg2
= convert_from_reference (arg2
);
5094 arg2_type
= TREE_TYPE (arg2
);
5095 /* Even if CONV2 is a valid conversion, the result of the
5096 conversion may be invalid. For example, if ARG3 has type
5097 "volatile X", and X does not have a copy constructor
5098 accepting a "volatile X&", then even if ARG2 can be
5099 converted to X, the conversion will fail. */
5100 if (error_operand_p (arg2
))
5101 result
= error_mark_node
;
5104 else if (conv3
&& !conv3
->bad_p
)
5106 arg3
= convert_like (conv3
, arg3
, complain
);
5107 arg3
= convert_from_reference (arg3
);
5108 arg3_type
= TREE_TYPE (arg3
);
5109 if (error_operand_p (arg3
))
5110 result
= error_mark_node
;
5114 /* Free all the conversions we allocated. */
5115 obstack_free (&conversion_obstack
, p
);
5120 /* If, after the conversion, both operands have class type,
5121 treat the cv-qualification of both operands as if it were the
5122 union of the cv-qualification of the operands.
5124 The standard is not clear about what to do in this
5125 circumstance. For example, if the first operand has type
5126 "const X" and the second operand has a user-defined
5127 conversion to "volatile X", what is the type of the second
5128 operand after this step? Making it be "const X" (matching
5129 the first operand) seems wrong, as that discards the
5130 qualification without actually performing a copy. Leaving it
5131 as "volatile X" seems wrong as that will result in the
5132 conditional expression failing altogether, even though,
5133 according to this step, the one operand could be converted to
5134 the type of the other. */
5136 && CLASS_TYPE_P (arg2_type
)
5137 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5138 arg2_type
= arg3_type
=
5139 cp_build_qualified_type (arg2_type
,
5140 cp_type_quals (arg2_type
)
5141 | cp_type_quals (arg3_type
));
5146 If the second and third operands are glvalues of the same value
5147 category and have the same type, the result is of that type and
5149 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5150 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5151 && same_type_p (arg2_type
, arg3_type
))
5153 result_type
= arg2_type
;
5154 if (processing_template_decl
)
5155 /* Let lvalue_kind know this was a glvalue. */
5156 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg2
));
5158 arg2
= mark_lvalue_use (arg2
);
5159 arg3
= mark_lvalue_use (arg3
);
5160 goto valid_operands
;
5165 Otherwise, the result is an rvalue. If the second and third
5166 operand do not have the same type, and either has (possibly
5167 cv-qualified) class type, overload resolution is used to
5168 determine the conversions (if any) to be applied to the operands
5169 (_over.match.oper_, _over.built_). */
5171 if (!same_type_p (arg2_type
, arg3_type
)
5172 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5178 /* Rearrange the arguments so that add_builtin_candidate only has
5179 to know about two args. In build_builtin_candidate, the
5180 arguments are unscrambled. */
5184 add_builtin_candidates (&candidates
,
5187 ovl_op_identifier (false, COND_EXPR
),
5189 LOOKUP_NORMAL
, complain
);
5193 If the overload resolution fails, the program is
5195 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5198 if (complain
& tf_error
)
5199 error_at (loc
, "operands to ?: have different types %qT and %qT",
5200 arg2_type
, arg3_type
);
5201 return error_mark_node
;
5203 cand
= tourney (candidates
, complain
);
5206 if (complain
& tf_error
)
5208 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5209 print_z_candidates (loc
, candidates
);
5211 return error_mark_node
;
5216 Otherwise, the conversions thus determined are applied, and
5217 the converted operands are used in place of the original
5218 operands for the remainder of this section. */
5219 conv
= cand
->convs
[0];
5220 arg1
= convert_like (conv
, arg1
, complain
);
5221 conv
= cand
->convs
[1];
5222 arg2
= convert_like (conv
, arg2
, complain
);
5223 arg2_type
= TREE_TYPE (arg2
);
5224 conv
= cand
->convs
[2];
5225 arg3
= convert_like (conv
, arg3
, complain
);
5226 arg3_type
= TREE_TYPE (arg3
);
5231 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5232 and function-to-pointer (_conv.func_) standard conversions are
5233 performed on the second and third operands.
5235 We need to force the lvalue-to-rvalue conversion here for class types,
5236 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5237 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5240 arg2
= force_rvalue (arg2
, complain
);
5241 if (!CLASS_TYPE_P (arg2_type
))
5242 arg2_type
= TREE_TYPE (arg2
);
5244 arg3
= force_rvalue (arg3
, complain
);
5245 if (!CLASS_TYPE_P (arg3_type
))
5246 arg3_type
= TREE_TYPE (arg3
);
5248 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5249 return error_mark_node
;
5253 After those conversions, one of the following shall hold:
5255 --The second and third operands have the same type; the result is of
5257 if (same_type_p (arg2_type
, arg3_type
))
5258 result_type
= arg2_type
;
5261 --The second and third operands have arithmetic or enumeration
5262 type; the usual arithmetic conversions are performed to bring
5263 them to a common type, and the result is of that type. */
5264 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5265 || UNSCOPED_ENUM_P (arg2_type
))
5266 && (ARITHMETIC_TYPE_P (arg3_type
)
5267 || UNSCOPED_ENUM_P (arg3_type
)))
5269 /* In this case, there is always a common type. */
5270 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5272 if (complain
& tf_warning
)
5273 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5274 "implicit conversion from %qH to %qI to "
5275 "match other result of conditional",
5278 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5279 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5281 if (TREE_CODE (orig_arg2
) == CONST_DECL
5282 && TREE_CODE (orig_arg3
) == CONST_DECL
5283 && DECL_CONTEXT (orig_arg2
) == DECL_CONTEXT (orig_arg3
))
5284 /* Two enumerators from the same enumeration can have different
5285 types when the enumeration is still being defined. */;
5286 else if (complain
& tf_warning
)
5287 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5288 "conditional expression: %qT vs %qT",
5289 arg2_type
, arg3_type
);
5291 else if (extra_warnings
5292 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5293 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5294 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5295 && !same_type_p (arg2_type
,
5296 type_promotes_to (arg3_type
)))))
5298 if (complain
& tf_warning
)
5299 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5300 "conditional expression");
5303 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5304 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5308 --The second and third operands have pointer type, or one has
5309 pointer type and the other is a null pointer constant; pointer
5310 conversions (_conv.ptr_) and qualification conversions
5311 (_conv.qual_) are performed to bring them to their composite
5312 pointer type (_expr.rel_). The result is of the composite
5315 --The second and third operands have pointer to member type, or
5316 one has pointer to member type and the other is a null pointer
5317 constant; pointer to member conversions (_conv.mem_) and
5318 qualification conversions (_conv.qual_) are performed to bring
5319 them to a common type, whose cv-qualification shall match the
5320 cv-qualification of either the second or the third operand.
5321 The result is of the common type. */
5322 else if ((null_ptr_cst_p (arg2
)
5323 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5324 || (null_ptr_cst_p (arg3
)
5325 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5326 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5327 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5328 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5330 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5331 arg3
, CPO_CONDITIONAL_EXPR
,
5333 if (result_type
== error_mark_node
)
5334 return error_mark_node
;
5335 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5336 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5341 if (complain
& tf_error
)
5342 error_at (loc
, "operands to ?: have different types %qT and %qT",
5343 arg2_type
, arg3_type
);
5344 return error_mark_node
;
5347 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5348 return error_mark_node
;
5351 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5353 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5354 warn here, because the COND_EXPR will be turned into ARG2. */
5355 if (warn_duplicated_branches
5356 && (complain
& tf_warning
)
5357 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5358 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5359 "this condition has identical branches");
5361 /* We can't use result_type below, as fold might have returned a
5366 /* Expand both sides into the same slot, hopefully the target of
5367 the ?: expression. We used to check for TARGET_EXPRs here,
5368 but now we sometimes wrap them in NOP_EXPRs so the test would
5370 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5371 result
= get_target_expr_sfinae (result
, complain
);
5372 /* If this expression is an rvalue, but might be mistaken for an
5373 lvalue, we must add a NON_LVALUE_EXPR. */
5374 result
= rvalue (result
);
5377 result
= force_paren_expr (result
);
5382 /* Wrapper for above. */
5385 build_conditional_expr (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
5386 tsubst_flags_t complain
)
5389 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5390 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5391 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5395 /* OPERAND is an operand to an expression. Perform necessary steps
5396 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5400 prep_operand (tree operand
)
5404 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5405 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5406 /* Make sure the template type is instantiated now. */
5407 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5413 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5414 OVERLOAD) to the CANDIDATES, returning an updated list of
5415 CANDIDATES. The ARGS are the arguments provided to the call;
5416 if FIRST_ARG is non-null it is the implicit object argument,
5417 otherwise the first element of ARGS is used if needed. The
5418 EXPLICIT_TARGS are explicit template arguments provided.
5419 TEMPLATE_ONLY is true if only template functions should be
5420 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5421 add_function_candidate. */
5424 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5426 tree explicit_targs
, bool template_only
,
5427 tree conversion_path
, tree access_path
,
5429 struct z_candidate
**candidates
,
5430 tsubst_flags_t complain
)
5433 const vec
<tree
, va_gc
> *non_static_args
;
5434 bool check_list_ctor
= false;
5435 bool check_converting
= false;
5436 unification_kind_t strict
;
5441 /* Precalculate special handling of constructors and conversion ops. */
5442 tree fn
= OVL_FIRST (fns
);
5443 if (DECL_CONV_FN_P (fn
))
5445 check_list_ctor
= false;
5446 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5447 if (flags
& LOOKUP_NO_CONVERSION
)
5448 /* We're doing return_type(x). */
5449 strict
= DEDUCE_CONV
;
5451 /* We're doing x.operator return_type(). */
5452 strict
= DEDUCE_EXACT
;
5453 /* [over.match.funcs] For conversion functions, the function
5454 is considered to be a member of the class of the implicit
5455 object argument for the purpose of defining the type of
5456 the implicit object parameter. */
5457 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5461 if (DECL_CONSTRUCTOR_P (fn
))
5463 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5464 /* For list-initialization we consider explicit constructors
5465 and complain if one is chosen. */
5467 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5468 == LOOKUP_ONLYCONVERTING
);
5470 strict
= DEDUCE_CALL
;
5471 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5475 non_static_args
= args
;
5477 /* Delay creating the implicit this parameter until it is needed. */
5478 non_static_args
= NULL
;
5480 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5484 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5486 if (check_list_ctor
&& !is_list_ctor (fn
))
5489 tree fn_first_arg
= NULL_TREE
;
5490 const vec
<tree
, va_gc
> *fn_args
= args
;
5492 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5494 /* Figure out where the object arg comes from. If this
5495 function is a non-static member and we didn't get an
5496 implicit object argument, move it out of args. */
5497 if (first_arg
== NULL_TREE
)
5501 vec
<tree
, va_gc
> *tempvec
;
5502 vec_alloc (tempvec
, args
->length () - 1);
5503 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5504 tempvec
->quick_push (arg
);
5505 non_static_args
= tempvec
;
5506 first_arg
= (*args
)[0];
5509 fn_first_arg
= first_arg
;
5510 fn_args
= non_static_args
;
5513 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5514 add_template_candidate (candidates
,
5526 else if (!template_only
)
5527 add_function_candidate (candidates
,
5539 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5540 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5543 op_is_ordered (tree_code code
)
5549 return (flag_strong_eval_order
> 1 ? -1 : 0);
5553 return (flag_strong_eval_order
> 1 ? 1 : 0);
5556 // Not overloadable (yet).
5558 // Only one argument.
5565 return (flag_strong_eval_order
? 1 : 0);
5573 build_new_op_1 (location_t loc
, enum tree_code code
, int flags
, tree arg1
,
5574 tree arg2
, tree arg3
, tree
*overload
, tsubst_flags_t complain
)
5576 struct z_candidate
*candidates
= 0, *cand
;
5577 vec
<tree
, va_gc
> *arglist
;
5579 tree result
= NULL_TREE
;
5580 bool result_valid_p
= false;
5581 enum tree_code code2
= NOP_EXPR
;
5582 enum tree_code code_orig_arg1
= ERROR_MARK
;
5583 enum tree_code code_orig_arg2
= ERROR_MARK
;
5589 if (error_operand_p (arg1
)
5590 || error_operand_p (arg2
)
5591 || error_operand_p (arg3
))
5592 return error_mark_node
;
5594 bool ismodop
= code
== MODIFY_EXPR
;
5597 code2
= TREE_CODE (arg3
);
5600 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5602 arg1
= prep_operand (arg1
);
5604 bool memonly
= false;
5609 case VEC_DELETE_EXPR
:
5611 /* Use build_op_new_call and build_op_delete_call instead. */
5615 /* Use build_op_call instead. */
5618 case TRUTH_ORIF_EXPR
:
5619 case TRUTH_ANDIF_EXPR
:
5620 case TRUTH_AND_EXPR
:
5622 /* These are saved for the sake of warn_logical_operator. */
5623 code_orig_arg1
= TREE_CODE (arg1
);
5624 code_orig_arg2
= TREE_CODE (arg2
);
5632 /* These are saved for the sake of maybe_warn_bool_compare. */
5633 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5634 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5637 /* =, ->, [], () must be non-static member functions. */
5639 if (code2
!= NOP_EXPR
)
5651 arg2
= prep_operand (arg2
);
5652 arg3
= prep_operand (arg3
);
5654 if (code
== COND_EXPR
)
5655 /* Use build_conditional_expr instead. */
5657 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5658 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5661 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5662 arg2
= integer_zero_node
;
5664 vec_alloc (arglist
, 3);
5665 arglist
->quick_push (arg1
);
5666 if (arg2
!= NULL_TREE
)
5667 arglist
->quick_push (arg2
);
5668 if (arg3
!= NULL_TREE
)
5669 arglist
->quick_push (arg3
);
5671 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5672 p
= conversion_obstack_alloc (0);
5674 /* Add namespace-scope operators to the list of functions to
5678 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5679 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5680 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5681 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5682 flags
, &candidates
, complain
);
5687 args
[2] = NULL_TREE
;
5689 /* Add class-member operators to the candidate set. */
5690 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5694 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5695 if (fns
== error_mark_node
)
5697 result
= error_mark_node
;
5698 goto user_defined_result_ready
;
5701 add_candidates (BASELINK_FUNCTIONS (fns
),
5702 NULL_TREE
, arglist
, NULL_TREE
,
5704 BASELINK_BINFO (fns
),
5705 BASELINK_ACCESS_BINFO (fns
),
5706 flags
, &candidates
, complain
);
5708 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5709 only non-member functions that have type T1 or reference to
5710 cv-qualified-opt T1 for the first argument, if the first argument
5711 has an enumeration type, or T2 or reference to cv-qualified-opt
5712 T2 for the second argument, if the second argument has an
5713 enumeration type. Filter out those that don't match. */
5714 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5716 struct z_candidate
**candp
, **next
;
5718 for (candp
= &candidates
; *candp
; candp
= next
)
5720 tree parmlist
, parmtype
;
5721 int i
, nargs
= (arg2
? 2 : 1);
5726 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5728 for (i
= 0; i
< nargs
; ++i
)
5730 parmtype
= TREE_VALUE (parmlist
);
5732 if (TREE_CODE (parmtype
) == REFERENCE_TYPE
)
5733 parmtype
= TREE_TYPE (parmtype
);
5734 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5735 && (same_type_ignoring_top_level_qualifiers_p
5736 (TREE_TYPE (args
[i
]), parmtype
)))
5739 parmlist
= TREE_CHAIN (parmlist
);
5742 /* No argument has an appropriate type, so remove this
5743 candidate function from the list. */
5746 *candp
= cand
->next
;
5752 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5759 /* For these, the built-in candidates set is empty
5760 [over.match.oper]/3. We don't want non-strict matches
5761 because exact matches are always possible with built-in
5762 operators. The built-in candidate set for COMPONENT_REF
5763 would be empty too, but since there are no such built-in
5764 operators, we accept non-strict matches for them. */
5773 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5778 case POSTINCREMENT_EXPR
:
5779 case POSTDECREMENT_EXPR
:
5780 /* Don't try anything fancy if we're not allowed to produce
5782 if (!(complain
& tf_error
))
5783 return error_mark_node
;
5785 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5786 distinguish between prefix and postfix ++ and
5787 operator++() was used for both, so we allow this with
5791 const char *msg
= (flag_permissive
)
5792 ? G_("no %<%D(int)%> declared for postfix %qs,"
5793 " trying prefix operator instead")
5794 : G_("no %<%D(int)%> declared for postfix %qs");
5795 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
5798 if (!flag_permissive
)
5799 return error_mark_node
;
5801 if (code
== POSTINCREMENT_EXPR
)
5802 code
= PREINCREMENT_EXPR
;
5804 code
= PREDECREMENT_EXPR
;
5805 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5806 NULL_TREE
, overload
, complain
);
5809 /* The caller will deal with these. */
5814 result_valid_p
= true;
5818 if (complain
& tf_error
)
5820 /* If one of the arguments of the operator represents
5821 an invalid use of member function pointer, try to report
5822 a meaningful error ... */
5823 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
5824 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
5825 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
5826 /* We displayed the error message. */;
5829 /* ... Otherwise, report the more generic
5830 "no matching operator found" error */
5831 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
5832 print_z_candidates (loc
, candidates
);
5835 result
= error_mark_node
;
5841 cand
= tourney (candidates
, complain
);
5844 if (complain
& tf_error
)
5846 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
5847 print_z_candidates (loc
, candidates
);
5849 result
= error_mark_node
;
5851 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
5854 *overload
= cand
->fn
;
5856 if (resolve_args (arglist
, complain
) == NULL
)
5857 result
= error_mark_node
;
5859 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
5861 if (trivial_fn_p (cand
->fn
))
5862 /* There won't be a CALL_EXPR. */;
5863 else if (result
&& result
!= error_mark_node
)
5865 tree call
= extract_call_expr (result
);
5866 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
5868 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
5869 /* This prevents build_new_function_call from discarding this
5870 function during instantiation of the enclosing template. */
5871 KOENIG_LOOKUP_P (call
) = 1;
5873 /* Specify evaluation order as per P0145R2. */
5874 CALL_EXPR_ORDERED_ARGS (call
) = false;
5875 switch (op_is_ordered (code
))
5878 CALL_EXPR_REVERSE_ARGS (call
) = true;
5882 CALL_EXPR_ORDERED_ARGS (call
) = true;
5892 /* Give any warnings we noticed during overload resolution. */
5893 if (cand
->warnings
&& (complain
& tf_warning
))
5895 struct candidate_warning
*w
;
5896 for (w
= cand
->warnings
; w
; w
= w
->next
)
5897 joust (cand
, w
->loser
, 1, complain
);
5900 /* Check for comparison of different enum types. */
5909 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
5910 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
5911 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
5912 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
5913 && (complain
& tf_warning
))
5915 warning (OPT_Wenum_compare
,
5916 "comparison between %q#T and %q#T",
5917 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
5924 /* We need to strip any leading REF_BIND so that bitfields
5925 don't cause errors. This should not remove any important
5926 conversions, because builtins don't apply to class
5927 objects directly. */
5928 conv
= cand
->convs
[0];
5929 if (conv
->kind
== ck_ref_bind
)
5930 conv
= next_conversion (conv
);
5931 arg1
= convert_like (conv
, arg1
, complain
);
5935 conv
= cand
->convs
[1];
5936 if (conv
->kind
== ck_ref_bind
)
5937 conv
= next_conversion (conv
);
5939 arg2
= decay_conversion (arg2
, complain
);
5941 /* We need to call warn_logical_operator before
5942 converting arg2 to a boolean_type, but after
5943 decaying an enumerator to its value. */
5944 if (complain
& tf_warning
)
5945 warn_logical_operator (loc
, code
, boolean_type_node
,
5946 code_orig_arg1
, arg1
,
5947 code_orig_arg2
, arg2
);
5949 arg2
= convert_like (conv
, arg2
, complain
);
5953 conv
= cand
->convs
[2];
5954 if (conv
->kind
== ck_ref_bind
)
5955 conv
= next_conversion (conv
);
5956 arg3
= convert_like (conv
, arg3
, complain
);
5962 user_defined_result_ready
:
5964 /* Free all the conversions we allocated. */
5965 obstack_free (&conversion_obstack
, p
);
5967 if (result
|| result_valid_p
)
5974 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
5977 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
5979 case TRUTH_ANDIF_EXPR
:
5980 case TRUTH_ORIF_EXPR
:
5981 case TRUTH_AND_EXPR
:
5983 if (complain
& tf_warning
)
5984 warn_logical_operator (loc
, code
, boolean_type_node
,
5985 code_orig_arg1
, arg1
,
5986 code_orig_arg2
, arg2
);
5994 if ((complain
& tf_warning
)
5995 && ((code_orig_arg1
== BOOLEAN_TYPE
)
5996 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
5997 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
5998 if (complain
& tf_warning
&& warn_tautological_compare
)
5999 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6004 case TRUNC_DIV_EXPR
:
6009 case TRUNC_MOD_EXPR
:
6013 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6015 case UNARY_PLUS_EXPR
:
6018 case TRUTH_NOT_EXPR
:
6019 case PREINCREMENT_EXPR
:
6020 case POSTINCREMENT_EXPR
:
6021 case PREDECREMENT_EXPR
:
6022 case POSTDECREMENT_EXPR
:
6026 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6029 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6032 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6036 /* The caller will deal with these. */
6048 /* Wrapper for above. */
6051 build_new_op (location_t loc
, enum tree_code code
, int flags
,
6052 tree arg1
, tree arg2
, tree arg3
,
6053 tree
*overload
, tsubst_flags_t complain
)
6056 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6057 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6058 overload
, complain
);
6059 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6063 /* CALL was returned by some call-building function; extract the actual
6064 CALL_EXPR from any bits that have been tacked on, e.g. by
6065 convert_from_reference. */
6068 extract_call_expr (tree call
)
6070 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6071 call
= TREE_OPERAND (call
, 1);
6072 if (REFERENCE_REF_P (call
))
6073 call
= TREE_OPERAND (call
, 0);
6074 if (TREE_CODE (call
) == TARGET_EXPR
)
6075 call
= TARGET_EXPR_INITIAL (call
);
6076 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6077 || TREE_CODE (call
) == AGGR_INIT_EXPR
6078 || call
== error_mark_node
);
6082 /* Returns true if FN has two parameters, of which the second has type
6086 second_parm_is_size_t (tree fn
)
6088 tree t
= FUNCTION_ARG_CHAIN (fn
);
6089 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6092 if (t
== void_list_node
)
6094 if (aligned_new_threshold
&& t
6095 && same_type_p (TREE_VALUE (t
), align_type_node
)
6096 && TREE_CHAIN (t
) == void_list_node
)
6101 /* True if T, an allocation function, has std::align_val_t as its second
6105 aligned_allocation_fn_p (tree t
)
6107 if (!aligned_new_threshold
)
6110 tree a
= FUNCTION_ARG_CHAIN (t
);
6111 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6114 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6115 function (3.7.4.2 [basic.stc.dynamic.deallocation]) with a parameter of
6116 std::align_val_t. */
6119 aligned_deallocation_fn_p (tree t
)
6121 if (!aligned_new_threshold
)
6124 /* A template instance is never a usual deallocation function,
6125 regardless of its signature. */
6126 if (TREE_CODE (t
) == TEMPLATE_DECL
6127 || primary_template_specialization_p (t
))
6130 tree a
= FUNCTION_ARG_CHAIN (t
);
6131 if (same_type_p (TREE_VALUE (a
), align_type_node
)
6132 && TREE_CHAIN (a
) == void_list_node
)
6134 if (!same_type_p (TREE_VALUE (a
), size_type_node
))
6137 if (a
&& same_type_p (TREE_VALUE (a
), align_type_node
)
6138 && TREE_CHAIN (a
) == void_list_node
)
6143 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
6144 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
6147 usual_deallocation_fn_p (tree t
)
6149 /* A template instance is never a usual deallocation function,
6150 regardless of its signature. */
6151 if (TREE_CODE (t
) == TEMPLATE_DECL
6152 || primary_template_specialization_p (t
))
6155 /* If a class T has a member deallocation function named operator delete
6156 with exactly one parameter, then that function is a usual
6157 (non-placement) deallocation function. If class T does not declare
6158 such an operator delete but does declare a member deallocation
6159 function named operator delete with exactly two parameters, the second
6160 of which has type std::size_t (18.2), then this function is a usual
6161 deallocation function. */
6162 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6163 tree chain
= FUNCTION_ARG_CHAIN (t
);
6166 if (chain
== void_list_node
6167 || ((!global
|| flag_sized_deallocation
)
6168 && second_parm_is_size_t (t
)))
6170 if (aligned_deallocation_fn_p (t
))
6175 /* Build a call to operator delete. This has to be handled very specially,
6176 because the restrictions on what signatures match are different from all
6177 other call instances. For a normal delete, only a delete taking (void *)
6178 or (void *, size_t) is accepted. For a placement delete, only an exact
6179 match with the placement new is accepted.
6181 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6182 ADDR is the pointer to be deleted.
6183 SIZE is the size of the memory block to be deleted.
6184 GLOBAL_P is true if the delete-expression should not consider
6185 class-specific delete operators.
6186 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6188 If this call to "operator delete" is being generated as part to
6189 deallocate memory allocated via a new-expression (as per [expr.new]
6190 which requires that if the initialization throws an exception then
6191 we call a deallocation function), then ALLOC_FN is the allocation
6195 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6196 bool global_p
, tree placement
,
6197 tree alloc_fn
, tsubst_flags_t complain
)
6199 tree fn
= NULL_TREE
;
6200 tree fns
, fnname
, type
, t
;
6202 if (addr
== error_mark_node
)
6203 return error_mark_node
;
6205 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6207 fnname
= ovl_op_identifier (false, code
);
6209 if (CLASS_TYPE_P (type
)
6210 && COMPLETE_TYPE_P (complete_type (type
))
6214 If the result of the lookup is ambiguous or inaccessible, or if
6215 the lookup selects a placement deallocation function, the
6216 program is ill-formed.
6218 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6220 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6221 if (fns
== error_mark_node
)
6222 return error_mark_node
;
6227 if (fns
== NULL_TREE
)
6228 fns
= lookup_name_nonclass (fnname
);
6230 /* Strip const and volatile from addr. */
6231 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6235 /* "A declaration of a placement deallocation function matches the
6236 declaration of a placement allocation function if it has the same
6237 number of parameters and, after parameter transformations (8.3.5),
6238 all parameter types except the first are identical."
6240 So we build up the function type we want and ask instantiate_type
6241 to get it for us. */
6242 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6243 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6244 t
= build_function_type (void_type_node
, t
);
6246 fn
= instantiate_type (t
, fns
, tf_none
);
6247 if (fn
== error_mark_node
)
6250 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6252 /* "If the lookup finds the two-parameter form of a usual deallocation
6253 function (3.7.4.2) and that function, considered as a placement
6254 deallocation function, would have been selected as a match for the
6255 allocation function, the program is ill-formed." */
6256 if (second_parm_is_size_t (fn
))
6258 const char *const msg1
6259 = G_("exception cleanup for this placement new selects "
6260 "non-placement operator delete");
6261 const char *const msg2
6262 = G_("%qD is a usual (non-placement) deallocation "
6263 "function in C++14 (or with -fsized-deallocation)");
6265 /* But if the class has an operator delete (void *), then that is
6266 the usual deallocation function, so we shouldn't complain
6267 about using the operator delete (void *, size_t). */
6268 if (DECL_CLASS_SCOPE_P (fn
))
6269 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6273 if (usual_deallocation_fn_p (elt
)
6274 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6277 /* Before C++14 a two-parameter global deallocation function is
6278 always a placement deallocation function, but warn if
6280 else if (!flag_sized_deallocation
)
6282 if ((complain
& tf_warning
)
6283 && warning (OPT_Wc__14_compat
, msg1
))
6284 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6288 if (complain
& tf_warning_or_error
)
6290 if (permerror (input_location
, msg1
))
6292 /* Only mention C++14 for namespace-scope delete. */
6293 if (DECL_NAMESPACE_SCOPE_P (fn
))
6294 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6296 inform (DECL_SOURCE_LOCATION (fn
),
6297 "%qD is a usual (non-placement) deallocation "
6302 return error_mark_node
;
6307 /* "Any non-placement deallocation function matches a non-placement
6308 allocation function. If the lookup finds a single matching
6309 deallocation function, that function will be called; otherwise, no
6310 deallocation function will be called." */
6311 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6314 if (usual_deallocation_fn_p (elt
))
6322 /* -- If the type has new-extended alignment, a function with a
6323 parameter of type std::align_val_t is preferred; otherwise a
6324 function without such a parameter is preferred. If exactly one
6325 preferred function is found, that function is selected and the
6326 selection process terminates. If more than one preferred
6327 function is found, all non-preferred functions are eliminated
6328 from further consideration. */
6329 if (aligned_new_threshold
)
6331 bool want_align
= type_has_new_extended_alignment (type
);
6332 bool fn_align
= aligned_deallocation_fn_p (fn
);
6333 bool elt_align
= aligned_deallocation_fn_p (elt
);
6335 if (elt_align
!= fn_align
)
6337 if (want_align
== elt_align
)
6343 /* -- If the deallocation functions have class scope, the one
6344 without a parameter of type std::size_t is selected. */
6346 if (DECL_CLASS_SCOPE_P (fn
))
6349 /* -- If the type is complete and if, for the second alternative
6350 (delete array) only, the operand is a pointer to a class type
6351 with a non-trivial destructor or a (possibly multi-dimensional)
6352 array thereof, the function with a parameter of type std::size_t
6355 -- Otherwise, it is unspecified whether a deallocation function
6356 with a parameter of type std::size_t is selected. */
6359 want_size
= COMPLETE_TYPE_P (type
);
6360 if (code
== VEC_DELETE_EXPR
6361 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6362 /* We need a cookie to determine the array size. */
6365 bool fn_size
= second_parm_is_size_t (fn
);
6366 bool elt_size
= second_parm_is_size_t (elt
);
6367 gcc_assert (fn_size
!= elt_size
);
6368 if (want_size
== elt_size
)
6373 /* If we have a matching function, call it. */
6376 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6378 /* If the FN is a member function, make sure that it is
6380 if (BASELINK_P (fns
))
6381 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6384 /* Core issue 901: It's ok to new a type with deleted delete. */
6385 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6390 /* The placement args might not be suitable for overload
6391 resolution at this point, so build the call directly. */
6392 int nargs
= call_expr_nargs (placement
);
6393 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6396 for (i
= 1; i
< nargs
; i
++)
6397 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6398 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6399 return error_mark_node
;
6400 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6405 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6406 args
->quick_push (addr
);
6407 if (second_parm_is_size_t (fn
))
6408 args
->quick_push (size
);
6409 if (aligned_deallocation_fn_p (fn
))
6411 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6412 args
->quick_push (al
);
6414 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6415 release_tree_vector (args
);
6422 If no unambiguous matching deallocation function can be found,
6423 propagating the exception does not cause the object's memory to
6427 if ((complain
& tf_warning
)
6429 warning (0, "no corresponding deallocation function for %qD",
6434 if (complain
& tf_error
)
6435 error ("no suitable %<operator %s%> for %qT",
6436 OVL_OP_INFO (false, code
)->name
, type
);
6437 return error_mark_node
;
6440 /* If the current scope isn't allowed to access DECL along
6441 BASETYPE_PATH, give an error. The most derived class in
6442 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6443 the declaration to use in the error diagnostic. */
6446 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6447 tsubst_flags_t complain
, access_failure_info
*afi
)
6449 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6451 if (flag_new_inheriting_ctors
6452 && DECL_INHERITED_CTOR (decl
))
6454 /* 7.3.3/18: The additional constructors are accessible if they would be
6455 accessible when used to construct an object of the corresponding base
6457 decl
= strip_inheriting_ctors (decl
);
6458 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6459 ba_any
, NULL
, complain
);
6462 if (!accessible_p (basetype_path
, decl
, true))
6464 if (complain
& tf_error
)
6466 if (flag_new_inheriting_ctors
)
6467 diag_decl
= strip_inheriting_ctors (diag_decl
);
6468 if (TREE_PRIVATE (decl
))
6470 error ("%q#D is private within this context", diag_decl
);
6471 inform (DECL_SOURCE_LOCATION (diag_decl
),
6472 "declared private here");
6474 afi
->record_access_failure (basetype_path
, diag_decl
);
6476 else if (TREE_PROTECTED (decl
))
6478 error ("%q#D is protected within this context", diag_decl
);
6479 inform (DECL_SOURCE_LOCATION (diag_decl
),
6480 "declared protected here");
6482 afi
->record_access_failure (basetype_path
, diag_decl
);
6486 error ("%q#D is inaccessible within this context", diag_decl
);
6487 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6489 afi
->record_access_failure (basetype_path
, diag_decl
);
6498 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6499 bitwise or of LOOKUP_* values. If any errors are warnings are
6500 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6501 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6505 build_temp (tree expr
, tree type
, int flags
,
6506 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6509 vec
<tree
, va_gc
> *args
;
6511 *diagnostic_kind
= DK_UNSPECIFIED
;
6513 /* If the source is a packed field, calling the copy constructor will require
6514 binding the field to the reference parameter to the copy constructor, and
6515 we'll end up with an infinite loop. If we can use a bitwise copy, then
6517 if ((lvalue_kind (expr
) & clk_packed
)
6518 && CLASS_TYPE_P (TREE_TYPE (expr
))
6519 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6520 return get_target_expr_sfinae (expr
, complain
);
6522 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6523 args
= make_tree_vector_single (expr
);
6524 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6525 &args
, type
, flags
, complain
);
6526 release_tree_vector (args
);
6527 if (warningcount
+ werrorcount
> savew
)
6528 *diagnostic_kind
= DK_WARNING
;
6529 else if (errorcount
> savee
)
6530 *diagnostic_kind
= DK_ERROR
;
6534 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6535 EXPR is implicitly converted to type TOTYPE.
6536 FN and ARGNUM are used for diagnostics. */
6539 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6541 /* Issue warnings about peculiar, but valid, uses of NULL. */
6542 if (null_node_p (expr
) && TREE_CODE (totype
) != BOOLEAN_TYPE
6543 && ARITHMETIC_TYPE_P (totype
))
6545 source_location loc
=
6546 expansion_point_location_if_in_system_header (input_location
);
6549 warning_at (loc
, OPT_Wconversion_null
,
6550 "passing NULL to non-pointer argument %P of %qD",
6553 warning_at (loc
, OPT_Wconversion_null
,
6554 "converting to non-pointer type %qT from NULL", totype
);
6557 /* Issue warnings if "false" is converted to a NULL pointer */
6558 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6559 && TYPE_PTR_P (totype
))
6562 warning_at (input_location
, OPT_Wconversion_null
,
6563 "converting %<false%> to pointer type for argument %P "
6564 "of %qD", argnum
, fn
);
6566 warning_at (input_location
, OPT_Wconversion_null
,
6567 "converting %<false%> to pointer type %qT", totype
);
6571 /* We gave a diagnostic during a conversion. If this was in the second
6572 standard conversion sequence of a user-defined conversion sequence, say
6573 which user-defined conversion. */
6576 maybe_print_user_conv_context (conversion
*convs
)
6578 if (convs
->user_conv_p
)
6579 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6580 if (t
->kind
== ck_user
)
6582 print_z_candidate (0, " after user-defined conversion:",
6588 /* Locate the parameter with the given index within FNDECL.
6589 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6590 Return the location of the FNDECL itself if there are problems. */
6593 get_fndecl_argument_location (tree fndecl
, int argnum
)
6598 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6599 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6600 i
< argnum
&& param
;
6601 i
++, param
= TREE_CHAIN (param
))
6604 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6605 return the location of FNDECL. */
6607 return DECL_SOURCE_LOCATION (fndecl
);
6609 return DECL_SOURCE_LOCATION (param
);
6612 /* Perform the conversions in CONVS on the expression EXPR. FN and
6613 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6614 indicates the `this' argument of a method. INNER is nonzero when
6615 being called to continue a conversion chain. It is negative when a
6616 reference binding will be applied, positive otherwise. If
6617 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6618 conversions will be emitted if appropriate. If C_CAST_P is true,
6619 this conversion is coming from a C-style cast; in that case,
6620 conversions to inaccessible bases are permitted. */
6623 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6624 bool issue_conversion_warnings
,
6625 bool c_cast_p
, tsubst_flags_t complain
)
6627 tree totype
= convs
->type
;
6628 diagnostic_t diag_kind
;
6630 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6632 if (convs
->bad_p
&& !(complain
& tf_error
))
6633 return error_mark_node
;
6636 && convs
->kind
!= ck_user
6637 && convs
->kind
!= ck_list
6638 && convs
->kind
!= ck_ambig
6639 && (convs
->kind
!= ck_ref_bind
6640 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6641 && (convs
->kind
!= ck_rvalue
6642 || SCALAR_TYPE_P (totype
))
6643 && convs
->kind
!= ck_base
)
6645 bool complained
= false;
6646 conversion
*t
= convs
;
6648 /* Give a helpful error if this is bad because of excess braces. */
6649 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6650 && SCALAR_TYPE_P (totype
)
6651 && CONSTRUCTOR_NELTS (expr
) > 0
6652 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6654 complained
= permerror (loc
, "too many braces around initializer "
6656 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6657 && CONSTRUCTOR_NELTS (expr
) == 1)
6658 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6661 /* Give a helpful error if this is bad because a conversion to bool
6662 from std::nullptr_t requires direct-initialization. */
6663 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6664 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6665 complained
= permerror (loc
, "converting to %qH from %qI requires "
6666 "direct-initialization",
6667 totype
, TREE_TYPE (expr
));
6669 for (; t
; t
= next_conversion (t
))
6671 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6673 complained
= permerror (loc
, "invalid user-defined conversion "
6674 "from %qH to %qI", TREE_TYPE (expr
),
6677 print_z_candidate (loc
, "candidate is:", t
->cand
);
6678 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6679 /*issue_conversion_warnings=*/false,
6682 if (convs
->kind
== ck_ref_bind
)
6683 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6684 LOOKUP_NORMAL
, NULL_TREE
,
6687 expr
= cp_convert (totype
, expr
, complain
);
6688 if (complained
&& fn
)
6689 inform (DECL_SOURCE_LOCATION (fn
),
6690 " initializing argument %P of %qD", argnum
, fn
);
6693 else if (t
->kind
== ck_user
|| !t
->bad_p
)
6695 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6696 /*issue_conversion_warnings=*/false,
6701 else if (t
->kind
== ck_ambig
)
6702 return convert_like_real (t
, expr
, fn
, argnum
,
6703 /*issue_conversion_warnings=*/false,
6706 else if (t
->kind
== ck_identity
)
6710 complained
= permerror (loc
, "invalid conversion from %qH to %qI",
6711 TREE_TYPE (expr
), totype
);
6712 if (complained
&& fn
)
6713 inform (get_fndecl_argument_location (fn
, argnum
),
6714 " initializing argument %P of %qD", argnum
, fn
);
6716 return cp_convert (totype
, expr
, complain
);
6719 if (issue_conversion_warnings
&& (complain
& tf_warning
))
6720 conversion_null_warnings (totype
, expr
, fn
, argnum
);
6722 switch (convs
->kind
)
6726 struct z_candidate
*cand
= convs
->cand
;
6729 /* We chose the surrogate function from add_conv_candidate, now we
6730 actually need to build the conversion. */
6731 cand
= build_user_type_conversion_1 (totype
, expr
,
6732 LOOKUP_NO_CONVERSION
, complain
);
6734 tree convfn
= cand
->fn
;
6736 /* When converting from an init list we consider explicit
6737 constructors, but actually trying to call one is an error. */
6738 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
6739 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
6740 /* Unless this is for direct-list-initialization. */
6741 && !CONSTRUCTOR_IS_DIRECT_INIT (expr
)
6742 /* And in C++98 a default constructor can't be explicit. */
6743 && cxx_dialect
>= cxx11
)
6745 if (!(complain
& tf_error
))
6746 return error_mark_node
;
6747 location_t loc
= location_of (expr
);
6748 if (CONSTRUCTOR_NELTS (expr
) == 0
6749 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
6751 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
6752 "would use explicit constructor %qD",
6754 inform (loc
, "in C++11 and above a default constructor "
6758 error ("converting to %qT from initializer list would use "
6759 "explicit constructor %qD", totype
, convfn
);
6762 /* If we're initializing from {}, it's value-initialization. */
6763 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6764 && CONSTRUCTOR_NELTS (expr
) == 0
6765 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
6767 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
6768 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
6769 return error_mark_node
;
6770 expr
= build_value_init (totype
, complain
);
6771 expr
= get_target_expr_sfinae (expr
, complain
);
6772 if (expr
!= error_mark_node
)
6774 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6775 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
6780 expr
= mark_rvalue_use (expr
);
6782 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
6784 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
6787 /* If this is a constructor or a function returning an aggr type,
6788 we need to build up a TARGET_EXPR. */
6789 if (DECL_CONSTRUCTOR_P (convfn
))
6791 expr
= build_cplus_new (totype
, expr
, complain
);
6793 /* Remember that this was list-initialization. */
6794 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
6795 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6801 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
6803 int nelts
= CONSTRUCTOR_NELTS (expr
);
6805 expr
= build_value_init (totype
, complain
);
6806 else if (nelts
== 1)
6807 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6811 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
6812 /*read_p=*/true, UNKNOWN_LOCATION
,
6813 /*reject_builtin=*/true);
6815 if (type_unknown_p (expr
))
6816 expr
= instantiate_type (totype
, expr
, complain
);
6817 if (expr
== null_node
6818 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
6819 /* If __null has been converted to an integer type, we do not want to
6820 continue to warn about uses of EXPR as an integer, rather than as a
6822 expr
= build_int_cst (totype
, 0);
6825 /* We leave bad_p off ck_ambig because overload resolution considers
6826 it valid, it just fails when we try to perform it. So we need to
6827 check complain here, too. */
6828 if (complain
& tf_error
)
6830 /* Call build_user_type_conversion again for the error. */
6831 int flags
= (convs
->need_temporary_p
6832 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
6833 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
6834 gcc_assert (seen_error ());
6836 inform (DECL_SOURCE_LOCATION (fn
),
6837 " initializing argument %P of %qD", argnum
, fn
);
6839 return error_mark_node
;
6843 /* Conversion to std::initializer_list<T>. */
6844 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
6845 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
6846 unsigned len
= CONSTRUCTOR_NELTS (expr
);
6847 tree array
, val
, field
;
6848 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
6851 /* Convert all the elements. */
6852 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
6854 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
, argnum
,
6855 false, false, complain
);
6856 if (sub
== error_mark_node
)
6858 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
6859 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
6860 return error_mark_node
;
6861 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
), NULL_TREE
, sub
);
6862 if (!TREE_CONSTANT (sub
))
6863 TREE_CONSTANT (new_ctor
) = false;
6865 /* Build up the array. */
6866 elttype
= cp_build_qualified_type
6867 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
6868 array
= build_array_of_n_type (elttype
, len
);
6869 array
= finish_compound_literal (array
, new_ctor
, complain
);
6870 /* Take the address explicitly rather than via decay_conversion
6871 to avoid the error about taking the address of a temporary. */
6872 array
= cp_build_addr_expr (array
, complain
);
6873 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
6874 if (array
== error_mark_node
)
6875 return error_mark_node
;
6877 /* Build up the initializer_list object. */
6878 totype
= complete_type (totype
);
6879 field
= next_initializable_field (TYPE_FIELDS (totype
));
6880 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
6881 field
= next_initializable_field (DECL_CHAIN (field
));
6882 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
6883 new_ctor
= build_constructor (totype
, vec
);
6884 return get_target_expr_sfinae (new_ctor
, complain
);
6888 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
6890 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6891 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
6892 real
= perform_implicit_conversion (TREE_TYPE (totype
),
6894 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
6896 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
6899 expr
= reshape_init (totype
, expr
, complain
);
6900 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
6902 if (expr
!= error_mark_node
)
6903 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6910 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
6911 convs
->kind
== ck_ref_bind
6912 ? issue_conversion_warnings
: false,
6913 c_cast_p
, complain
);
6914 if (expr
== error_mark_node
)
6915 return error_mark_node
;
6917 switch (convs
->kind
)
6920 expr
= decay_conversion (expr
, complain
);
6921 if (expr
== error_mark_node
)
6923 if (complain
& tf_error
)
6925 maybe_print_user_conv_context (convs
);
6927 inform (DECL_SOURCE_LOCATION (fn
),
6928 " initializing argument %P of %qD", argnum
, fn
);
6930 return error_mark_node
;
6933 if (! MAYBE_CLASS_TYPE_P (totype
))
6936 /* Don't introduce copies when passing arguments along to the inherited
6938 if (current_function_decl
6939 && flag_new_inheriting_ctors
6940 && DECL_INHERITED_CTOR (current_function_decl
))
6943 if (TREE_CODE (expr
) == TARGET_EXPR
6944 && TARGET_EXPR_LIST_INIT_P (expr
))
6945 /* Copy-list-initialization doesn't actually involve a copy. */
6950 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
6952 /* We are going to bind a reference directly to a base-class
6953 subobject of EXPR. */
6954 /* Build an expression for `*((base*) &expr)'. */
6955 expr
= convert_to_base (expr
, totype
,
6956 !c_cast_p
, /*nonnull=*/true, complain
);
6960 /* Copy-initialization where the cv-unqualified version of the source
6961 type is the same class as, or a derived class of, the class of the
6962 destination [is treated as direct-initialization]. [dcl.init] */
6963 flags
= LOOKUP_NORMAL
;
6964 if (convs
->user_conv_p
)
6965 /* This conversion is being done in the context of a user-defined
6966 conversion (i.e. the second step of copy-initialization), so
6967 don't allow any more. */
6968 flags
|= LOOKUP_NO_CONVERSION
;
6970 flags
|= LOOKUP_ONLYCONVERTING
;
6971 if (convs
->rvaluedness_matches_p
)
6972 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
6973 flags
|= LOOKUP_PREFER_RVALUE
;
6974 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
6975 if (diag_kind
&& complain
)
6977 maybe_print_user_conv_context (convs
);
6979 inform (DECL_SOURCE_LOCATION (fn
),
6980 " initializing argument %P of %qD", argnum
, fn
);
6983 return build_cplus_new (totype
, expr
, complain
);
6987 tree ref_type
= totype
;
6989 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
6991 tree extype
= TREE_TYPE (expr
);
6992 if (TYPE_REF_IS_RVALUE (ref_type
)
6994 error_at (loc
, "cannot bind rvalue reference of type %qH to "
6995 "lvalue of type %qI", totype
, extype
);
6996 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
6997 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
6998 error_at (loc
, "cannot bind non-const lvalue reference of "
6999 "type %qH to an rvalue of type %qI", totype
, extype
);
7000 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7001 error_at (loc
, "binding reference of type %qH to %qI "
7002 "discards qualifiers", totype
, extype
);
7005 maybe_print_user_conv_context (convs
);
7007 inform (DECL_SOURCE_LOCATION (fn
),
7008 " initializing argument %P of %qD", argnum
, fn
);
7009 return error_mark_node
;
7012 /* If necessary, create a temporary.
7014 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7015 that need temporaries, even when their types are reference
7016 compatible with the type of reference being bound, so the
7017 upcoming call to cp_build_addr_expr doesn't fail. */
7018 if (convs
->need_temporary_p
7019 || TREE_CODE (expr
) == CONSTRUCTOR
7020 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7022 /* Otherwise, a temporary of type "cv1 T1" is created and
7023 initialized from the initializer expression using the rules
7024 for a non-reference copy-initialization (8.5). */
7026 tree type
= TREE_TYPE (ref_type
);
7027 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7029 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7030 (type
, next_conversion (convs
)->type
));
7031 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7032 && !TYPE_REF_IS_RVALUE (ref_type
))
7034 /* If the reference is volatile or non-const, we
7035 cannot create a temporary. */
7036 if (lvalue
& clk_bitfield
)
7037 error_at (loc
, "cannot bind bitfield %qE to %qT",
7039 else if (lvalue
& clk_packed
)
7040 error_at (loc
, "cannot bind packed field %qE to %qT",
7043 error_at (loc
, "cannot bind rvalue %qE to %qT",
7045 return error_mark_node
;
7047 /* If the source is a packed field, and we must use a copy
7048 constructor, then building the target expr will require
7049 binding the field to the reference parameter to the
7050 copy constructor, and we'll end up with an infinite
7051 loop. If we can use a bitwise copy, then we'll be
7053 if ((lvalue
& clk_packed
)
7054 && CLASS_TYPE_P (type
)
7055 && type_has_nontrivial_copy_init (type
))
7057 error_at (loc
, "cannot bind packed field %qE to %qT",
7059 return error_mark_node
;
7061 if (lvalue
& clk_bitfield
)
7063 expr
= convert_bitfield_to_declared_type (expr
);
7064 expr
= fold_convert (type
, expr
);
7066 expr
= build_target_expr_with_type (expr
, type
, complain
);
7069 /* Take the address of the thing to which we will bind the
7071 expr
= cp_build_addr_expr (expr
, complain
);
7072 if (expr
== error_mark_node
)
7073 return error_mark_node
;
7075 /* Convert it to a pointer to the type referred to by the
7076 reference. This will adjust the pointer if a derived to
7077 base conversion is being performed. */
7078 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7080 /* Convert the pointer to the desired reference type. */
7081 return build_nop (ref_type
, expr
);
7085 return decay_conversion (expr
, complain
);
7088 /* ??? Should the address of a transaction-safe pointer point to the TM
7089 clone, and this conversion look up the primary function? */
7090 return build_nop (totype
, expr
);
7093 /* Warn about deprecated conversion if appropriate. */
7094 string_conv_p (totype
, expr
, 1);
7099 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7100 /*nonnull=*/false, complain
);
7101 return build_nop (totype
, expr
);
7104 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7105 c_cast_p
, complain
);
7111 if (convs
->check_narrowing
7112 && !check_narrowing (totype
, expr
, complain
))
7113 return error_mark_node
;
7115 if (issue_conversion_warnings
)
7116 expr
= cp_convert_and_check (totype
, expr
, complain
);
7118 expr
= cp_convert (totype
, expr
, complain
);
7123 /* ARG is being passed to a varargs function. Perform any conversions
7124 required. Return the converted value. */
7127 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7130 location_t loc
= EXPR_LOC_OR_LOC (arg
, input_location
);
7134 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7135 standard conversions are performed. */
7136 arg
= decay_conversion (arg
, complain
);
7137 arg_type
= TREE_TYPE (arg
);
7140 If the argument has integral or enumeration type that is subject
7141 to the integral promotions (_conv.prom_), or a floating point
7142 type that is subject to the floating point promotion
7143 (_conv.fpprom_), the value of the argument is converted to the
7144 promoted type before the call. */
7145 if (TREE_CODE (arg_type
) == REAL_TYPE
7146 && (TYPE_PRECISION (arg_type
)
7147 < TYPE_PRECISION (double_type_node
))
7148 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7150 if ((complain
& tf_warning
)
7151 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7152 warning_at (loc
, OPT_Wdouble_promotion
,
7153 "implicit conversion from %qH to %qI when passing "
7154 "argument to function",
7155 arg_type
, double_type_node
);
7156 arg
= convert_to_real_nofold (double_type_node
, arg
);
7158 else if (NULLPTR_TYPE_P (arg_type
))
7159 arg
= null_pointer_node
;
7160 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7162 if (SCOPED_ENUM_P (arg_type
))
7164 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7166 prom
= cp_perform_integral_promotions (prom
, complain
);
7167 if (abi_version_crosses (6)
7168 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7169 && (complain
& tf_warning
))
7170 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
7171 "%qT before -fabi-version=6, %qT after", arg_type
,
7172 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7173 if (!abi_version_at_least (6))
7177 arg
= cp_perform_integral_promotions (arg
, complain
);
7180 arg
= require_complete_type_sfinae (arg
, complain
);
7181 arg_type
= TREE_TYPE (arg
);
7183 if (arg
!= error_mark_node
7184 /* In a template (or ill-formed code), we can have an incomplete type
7185 even after require_complete_type_sfinae, in which case we don't know
7186 whether it has trivial copy or not. */
7187 && COMPLETE_TYPE_P (arg_type
)
7188 && !cp_unevaluated_operand
)
7190 /* [expr.call] 5.2.2/7:
7191 Passing a potentially-evaluated argument of class type (Clause 9)
7192 with a non-trivial copy constructor or a non-trivial destructor
7193 with no corresponding parameter is conditionally-supported, with
7194 implementation-defined semantics.
7196 We support it as pass-by-invisible-reference, just like a normal
7199 If the call appears in the context of a sizeof expression,
7200 it is not potentially-evaluated. */
7201 if (type_has_nontrivial_copy_init (arg_type
)
7202 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7204 arg
= force_rvalue (arg
, complain
);
7205 if (complain
& tf_warning
)
7206 warning (OPT_Wconditionally_supported
,
7207 "passing objects of non-trivially-copyable "
7208 "type %q#T through %<...%> is conditionally supported",
7210 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7212 /* Build up a real lvalue-to-rvalue conversion in case the
7213 copy constructor is trivial but not callable. */
7214 else if (CLASS_TYPE_P (arg_type
))
7215 force_rvalue (arg
, complain
);
7222 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7225 build_x_va_arg (source_location loc
, tree expr
, tree type
)
7227 if (processing_template_decl
)
7229 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7230 SET_EXPR_LOCATION (r
, loc
);
7234 type
= complete_type_or_else (type
, NULL_TREE
);
7236 if (expr
== error_mark_node
|| !type
)
7237 return error_mark_node
;
7239 expr
= mark_lvalue_use (expr
);
7241 if (TREE_CODE (type
) == REFERENCE_TYPE
)
7243 error ("cannot receive reference type %qT through %<...%>", type
);
7244 return error_mark_node
;
7247 if (type_has_nontrivial_copy_init (type
)
7248 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7250 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7251 it as pass by invisible reference. */
7252 warning_at (loc
, OPT_Wconditionally_supported
,
7253 "receiving objects of non-trivially-copyable type %q#T "
7254 "through %<...%> is conditionally-supported", type
);
7256 tree ref
= cp_build_reference_type (type
, false);
7257 expr
= build_va_arg (loc
, expr
, ref
);
7258 return convert_from_reference (expr
);
7261 tree ret
= build_va_arg (loc
, expr
, type
);
7262 if (CLASS_TYPE_P (type
))
7263 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7264 know how to handle it. */
7265 ret
= get_target_expr (ret
);
7269 /* TYPE has been given to va_arg. Apply the default conversions which
7270 would have happened when passed via ellipsis. Return the promoted
7271 type, or the passed type if there is no change. */
7274 cxx_type_promotes_to (tree type
)
7278 /* Perform the array-to-pointer and function-to-pointer
7280 type
= type_decays_to (type
);
7282 promote
= type_promotes_to (type
);
7283 if (same_type_p (type
, promote
))
7289 /* ARG is a default argument expression being passed to a parameter of
7290 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7291 zero-based argument number. Do any required conversions. Return
7292 the converted value. */
7294 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7296 push_defarg_context (tree fn
)
7297 { vec_safe_push (default_arg_context
, fn
); }
7300 pop_defarg_context (void)
7301 { default_arg_context
->pop (); }
7304 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7305 tsubst_flags_t complain
)
7310 /* See through clones. */
7311 fn
= DECL_ORIGIN (fn
);
7312 /* And inheriting ctors. */
7313 if (flag_new_inheriting_ctors
)
7314 fn
= strip_inheriting_ctors (fn
);
7316 /* Detect recursion. */
7317 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7320 if (complain
& tf_error
)
7321 error ("recursive evaluation of default argument for %q#D", fn
);
7322 return error_mark_node
;
7325 /* If the ARG is an unparsed default argument expression, the
7326 conversion cannot be performed. */
7327 if (TREE_CODE (arg
) == DEFAULT_ARG
)
7329 if (complain
& tf_error
)
7330 error ("call to %qD uses the default argument for parameter %P, which "
7331 "is not yet defined", fn
, parmnum
);
7332 return error_mark_node
;
7335 push_defarg_context (fn
);
7337 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7338 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7344 The names in the expression are bound, and the semantic
7345 constraints are checked, at the point where the default
7346 expressions appears.
7348 we must not perform access checks here. */
7349 push_deferring_access_checks (dk_no_check
);
7350 /* We must make a copy of ARG, in case subsequent processing
7351 alters any part of it. */
7352 arg
= break_out_target_exprs (arg
);
7353 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7354 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7356 arg
= convert_for_arg_passing (type
, arg
, complain
);
7357 pop_deferring_access_checks();
7359 pop_defarg_context ();
7364 /* Returns the type which will really be used for passing an argument of
7368 type_passed_as (tree type
)
7370 /* Pass classes with copy ctors by invisible reference. */
7371 if (TREE_ADDRESSABLE (type
))
7373 type
= build_reference_type (type
);
7374 /* There are no other pointers to this temporary. */
7375 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7377 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7378 && INTEGRAL_TYPE_P (type
)
7379 && COMPLETE_TYPE_P (type
)
7380 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7381 type
= integer_type_node
;
7386 /* Actually perform the appropriate conversion. */
7389 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7393 /* If VAL is a bitfield, then -- since it has already been converted
7394 to TYPE -- it cannot have a precision greater than TYPE.
7396 If it has a smaller precision, we must widen it here. For
7397 example, passing "int f:3;" to a function expecting an "int" will
7398 not result in any conversion before this point.
7400 If the precision is the same we must not risk widening. For
7401 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7402 often have type "int", even though the C++ type for the field is
7403 "long long". If the value is being passed to a function
7404 expecting an "int", then no conversions will be required. But,
7405 if we call convert_bitfield_to_declared_type, the bitfield will
7406 be converted to "long long". */
7407 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7409 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7410 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7412 if (val
== error_mark_node
)
7414 /* Pass classes with copy ctors by invisible reference. */
7415 else if (TREE_ADDRESSABLE (type
))
7416 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7417 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7418 && INTEGRAL_TYPE_P (type
)
7419 && COMPLETE_TYPE_P (type
)
7420 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7421 val
= cp_perform_integral_promotions (val
, complain
);
7422 if (complain
& tf_warning
)
7424 if (warn_suggest_attribute_format
)
7426 tree rhstype
= TREE_TYPE (val
);
7427 const enum tree_code coder
= TREE_CODE (rhstype
);
7428 const enum tree_code codel
= TREE_CODE (type
);
7429 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7431 && check_missing_format_attribute (type
, rhstype
))
7432 warning (OPT_Wsuggest_attribute_format
,
7433 "argument of function call might be a candidate "
7434 "for a format attribute");
7436 maybe_warn_parm_abi (type
, EXPR_LOC_OR_LOC (val
, input_location
));
7441 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7442 which just decay_conversion or no conversions at all should be done.
7443 This is true for some builtins which don't act like normal functions.
7444 Return 2 if no conversions at all should be done, 1 if just
7445 decay_conversion. Return 3 for special treatment of the 3rd argument
7446 for __builtin_*_overflow_p. */
7449 magic_varargs_p (tree fn
)
7451 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7452 switch (DECL_FUNCTION_CODE (fn
))
7454 case BUILT_IN_CLASSIFY_TYPE
:
7455 case BUILT_IN_CONSTANT_P
:
7456 case BUILT_IN_NEXT_ARG
:
7457 case BUILT_IN_VA_START
:
7460 case BUILT_IN_ADD_OVERFLOW_P
:
7461 case BUILT_IN_SUB_OVERFLOW_P
:
7462 case BUILT_IN_MUL_OVERFLOW_P
:
7466 return lookup_attribute ("type generic",
7467 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7473 /* Returns the decl of the dispatcher function if FN is a function version. */
7476 get_function_version_dispatcher (tree fn
)
7478 tree dispatcher_decl
= NULL
;
7480 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7481 && DECL_FUNCTION_VERSIONED (fn
));
7483 gcc_assert (targetm
.get_function_versions_dispatcher
);
7484 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7486 if (dispatcher_decl
== NULL
)
7488 error_at (input_location
, "use of multiversioned function "
7489 "without a default");
7493 retrofit_lang_decl (dispatcher_decl
);
7494 gcc_assert (dispatcher_decl
!= NULL
);
7495 return dispatcher_decl
;
7498 /* fn is a function version dispatcher that is marked used. Mark all the
7499 semantically identical function versions it will dispatch as used. */
7502 mark_versions_used (tree fn
)
7504 struct cgraph_node
*node
;
7505 struct cgraph_function_version_info
*node_v
;
7506 struct cgraph_function_version_info
*it_v
;
7508 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7510 node
= cgraph_node::get (fn
);
7514 gcc_assert (node
->dispatcher_function
);
7516 node_v
= node
->function_version ();
7520 /* All semantically identical versions are chained. Traverse and mark each
7521 one of them as used. */
7522 it_v
= node_v
->next
;
7523 while (it_v
!= NULL
)
7525 mark_used (it_v
->this_node
->decl
);
7530 /* Build a call to "the copy constructor" for the type of A, even if it
7531 wouldn't be selected by normal overload resolution. Used for
7535 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7537 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7538 tree binfo
= TYPE_BINFO (ctype
);
7539 tree copy
= get_copy_ctor (ctype
, complain
);
7540 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7541 tree ob
= build_dummy_object (ctype
);
7542 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7543 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7544 LOOKUP_NORMAL
, NULL
, complain
);
7545 release_tree_vector (args
);
7549 /* Return true iff T refers to a base field. */
7552 is_base_field_ref (tree t
)
7555 if (TREE_CODE (t
) == ADDR_EXPR
)
7556 t
= TREE_OPERAND (t
, 0);
7557 if (TREE_CODE (t
) == COMPONENT_REF
)
7558 t
= TREE_OPERAND (t
, 1);
7559 if (TREE_CODE (t
) == FIELD_DECL
)
7560 return DECL_FIELD_IS_BASE (t
);
7564 /* We can't elide a copy from a function returning by value to a base
7565 subobject, as the callee might clobber tail padding. Return true iff this
7566 could be that case. */
7569 unsafe_copy_elision_p (tree target
, tree exp
)
7571 /* Copy elision only happens with a TARGET_EXPR. */
7572 if (TREE_CODE (exp
) != TARGET_EXPR
)
7574 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7575 /* It's safe to elide the copy for a class with no tail padding. */
7576 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7578 /* It's safe to elide the copy if we aren't initializing a base object. */
7579 if (!is_base_field_ref (target
))
7581 tree init
= TARGET_EXPR_INITIAL (exp
);
7582 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7583 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7584 init
= TREE_OPERAND (init
, 1);
7585 if (TREE_CODE (init
) == COND_EXPR
)
7587 /* We'll end up copying from each of the arms of the COND_EXPR directly
7588 into the target, so look at them. */
7589 if (tree op
= TREE_OPERAND (init
, 1))
7590 if (unsafe_copy_elision_p (target
, op
))
7592 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7594 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7595 && !AGGR_INIT_VIA_CTOR_P (init
));
7598 /* True iff C is a conversion that binds a reference to a prvalue. */
7601 conv_binds_ref_to_prvalue (conversion
*c
)
7603 if (c
->kind
!= ck_ref_bind
)
7605 if (c
->need_temporary_p
)
7608 c
= next_conversion (c
);
7610 if (c
->kind
== ck_rvalue
)
7612 if (c
->kind
== ck_user
&& TREE_CODE (c
->type
) != REFERENCE_TYPE
)
7618 /* Subroutine of the various build_*_call functions. Overload resolution
7619 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7620 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7621 bitmask of various LOOKUP_* flags which apply to the call itself. */
7624 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7627 const vec
<tree
, va_gc
> *args
= cand
->args
;
7628 tree first_arg
= cand
->first_arg
;
7629 conversion
**convs
= cand
->convs
;
7631 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
7636 unsigned int arg_index
= 0;
7640 bool already_used
= false;
7642 /* In a template, there is no need to perform all of the work that
7643 is normally done. We are only interested in the type of the call
7644 expression, i.e., the return type of the function. Any semantic
7645 errors will be deferred until the template is instantiated. */
7646 if (processing_template_decl
)
7650 const tree
*argarray
;
7653 if (undeduced_auto_decl (fn
))
7654 mark_used (fn
, complain
);
7656 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
7660 return_type
= TREE_TYPE (TREE_TYPE (fn
));
7661 nargs
= vec_safe_length (args
);
7662 if (first_arg
== NULL_TREE
)
7663 argarray
= args
->address ();
7671 alcarray
= XALLOCAVEC (tree
, nargs
);
7672 alcarray
[0] = build_this (first_arg
);
7673 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
7674 alcarray
[ix
+ 1] = arg
;
7675 argarray
= alcarray
;
7678 addr
= build_addr_func (fn
, complain
);
7679 if (addr
== error_mark_node
)
7680 return error_mark_node
;
7681 expr
= build_call_array_loc (input_location
, return_type
,
7682 addr
, nargs
, argarray
);
7683 if (TREE_THIS_VOLATILE (fn
) && cfun
)
7684 current_function_returns_abnormally
= 1;
7685 return convert_from_reference (expr
);
7688 /* Give any warnings we noticed during overload resolution. */
7689 if (cand
->warnings
&& (complain
& tf_warning
))
7691 struct candidate_warning
*w
;
7692 for (w
= cand
->warnings
; w
; w
= w
->next
)
7693 joust (cand
, w
->loser
, 1, complain
);
7696 /* Core issue 2327: P0135 doesn't say how to handle the case where the
7697 argument to the copy constructor ends up being a prvalue after
7698 conversion. Let's do the normal processing, but pretend we aren't
7699 actually using the copy constructor. */
7700 bool force_elide
= false;
7701 if (cxx_dialect
>= cxx17
7702 && cand
->num_convs
== 1
7703 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
7704 && (DECL_COPY_CONSTRUCTOR_P (fn
)
7705 || DECL_MOVE_CONSTRUCTOR_P (fn
))
7706 && conv_binds_ref_to_prvalue (convs
[0]))
7709 goto not_really_used
;
7712 /* OK, we're actually calling this inherited constructor; set its deletedness
7713 appropriately. We can get away with doing this here because calling is
7714 the only way to refer to a constructor. */
7715 if (DECL_INHERITED_CTOR (fn
))
7716 deduce_inheriting_ctor (fn
);
7718 /* Make =delete work with SFINAE. */
7719 if (DECL_DELETED_FN (fn
))
7721 if (complain
& tf_error
)
7723 return error_mark_node
;
7726 if (DECL_FUNCTION_MEMBER_P (fn
))
7729 /* If FN is a template function, two cases must be considered.
7734 template <class T> void f();
7736 template <class T> struct B {
7740 struct C : A, B<int> {
7742 using B<int>::g; // #2
7745 In case #1 where `A::f' is a member template, DECL_ACCESS is
7746 recorded in the primary template but not in its specialization.
7747 We check access of FN using its primary template.
7749 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7750 because it is a member of class template B, DECL_ACCESS is
7751 recorded in the specialization `B<int>::g'. We cannot use its
7752 primary template because `B<T>::g' and `B<int>::g' may have
7753 different access. */
7754 if (DECL_TEMPLATE_INFO (fn
)
7755 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
7756 access_fn
= DECL_TI_TEMPLATE (fn
);
7759 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
7761 return error_mark_node
;
7764 /* If we're checking for implicit delete, don't bother with argument
7766 if (flags
& LOOKUP_SPECULATIVE
)
7768 if (cand
->viable
== 1)
7770 else if (!(complain
& tf_error
))
7771 /* Reject bad conversions now. */
7772 return error_mark_node
;
7773 /* else continue to get conversion error. */
7778 /* N3276 magic doesn't apply to nested calls. */
7779 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
7780 complain
&= ~tf_decltype
;
7781 /* No-Cleanup doesn't apply to nested calls either. */
7782 tsubst_flags_t no_cleanup_complain
= complain
;
7783 complain
&= ~tf_no_cleanup
;
7785 /* Find maximum size of vector to hold converted arguments. */
7786 parmlen
= list_length (parm
);
7787 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
7788 if (parmlen
> nargs
)
7790 argarray
= XALLOCAVEC (tree
, nargs
);
7792 /* The implicit parameters to a constructor are not considered by overload
7793 resolution, and must be of the proper type. */
7794 if (DECL_CONSTRUCTOR_P (fn
))
7797 if (first_arg
!= NULL_TREE
)
7799 object_arg
= first_arg
;
7800 first_arg
= NULL_TREE
;
7804 object_arg
= (*args
)[arg_index
];
7807 argarray
[j
++] = build_this (object_arg
);
7808 parm
= TREE_CHAIN (parm
);
7809 /* We should never try to call the abstract constructor. */
7810 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
7812 if (DECL_HAS_VTT_PARM_P (fn
))
7814 argarray
[j
++] = (*args
)[arg_index
];
7816 parm
= TREE_CHAIN (parm
);
7819 if (flags
& LOOKUP_PREFER_RVALUE
)
7821 /* The implicit move specified in 15.8.3/3 fails "...if the type of
7822 the first parameter of the selected constructor is not an rvalue
7823 reference to the object’s type (possibly cv-qualified)...." */
7824 gcc_assert (!(complain
& tf_error
));
7825 tree ptype
= convs
[0]->type
;
7826 if (TREE_CODE (ptype
) != REFERENCE_TYPE
7827 || !TYPE_REF_IS_RVALUE (ptype
)
7828 || CONVERSION_RANK (convs
[0]) > cr_exact
)
7829 return error_mark_node
;
7832 /* Bypass access control for 'this' parameter. */
7833 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
7835 tree parmtype
= TREE_VALUE (parm
);
7836 tree arg
= build_this (first_arg
!= NULL_TREE
7838 : (*args
)[arg_index
]);
7839 tree argtype
= TREE_TYPE (arg
);
7843 if (arg
== error_mark_node
)
7844 return error_mark_node
;
7846 if (convs
[i
]->bad_p
)
7848 if (complain
& tf_error
)
7850 if (permerror (input_location
, "passing %qT as %<this%> "
7851 "argument discards qualifiers",
7852 TREE_TYPE (argtype
)))
7853 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
7856 return error_mark_node
;
7859 /* See if the function member or the whole class type is declared
7860 final and the call can be devirtualized. */
7861 if (DECL_FINAL_P (fn
)
7862 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
7863 flags
|= LOOKUP_NONVIRTUAL
;
7865 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
7866 X is called for an object that is not of type X, or of a type
7867 derived from X, the behavior is undefined.
7869 So we can assume that anything passed as 'this' is non-null, and
7870 optimize accordingly. */
7871 gcc_assert (TYPE_PTR_P (parmtype
));
7872 /* Convert to the base in which the function was declared. */
7873 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
7874 converted_arg
= build_base_path (PLUS_EXPR
,
7876 cand
->conversion_path
,
7878 /* Check that the base class is accessible. */
7879 if (!accessible_base_p (TREE_TYPE (argtype
),
7880 BINFO_TYPE (cand
->conversion_path
), true))
7882 if (complain
& tf_error
)
7883 error ("%qT is not an accessible base of %qT",
7884 BINFO_TYPE (cand
->conversion_path
),
7885 TREE_TYPE (argtype
));
7887 return error_mark_node
;
7889 /* If fn was found by a using declaration, the conversion path
7890 will be to the derived class, not the base declaring fn. We
7891 must convert from derived to base. */
7892 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
7893 TREE_TYPE (parmtype
), ba_unique
,
7895 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
7896 base_binfo
, 1, complain
);
7898 argarray
[j
++] = converted_arg
;
7899 parm
= TREE_CHAIN (parm
);
7900 if (first_arg
!= NULL_TREE
)
7901 first_arg
= NULL_TREE
;
7908 gcc_assert (first_arg
== NULL_TREE
);
7909 for (; arg_index
< vec_safe_length (args
) && parm
;
7910 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
7912 tree type
= TREE_VALUE (parm
);
7913 tree arg
= (*args
)[arg_index
];
7914 bool conversion_warning
= true;
7918 /* If the argument is NULL and used to (implicitly) instantiate a
7919 template function (and bind one of the template arguments to
7920 the type of 'long int'), we don't want to warn about passing NULL
7921 to non-pointer argument.
7922 For example, if we have this template function:
7924 template<typename T> void func(T x) {}
7926 we want to warn (when -Wconversion is enabled) in this case:
7932 but not in this case:
7938 if (null_node_p (arg
)
7939 && DECL_TEMPLATE_INFO (fn
)
7940 && cand
->template_decl
7941 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
7942 conversion_warning
= false;
7944 /* Warn about initializer_list deduction that isn't currently in the
7946 if (cxx_dialect
> cxx98
7947 && flag_deduce_init_list
7948 && cand
->template_decl
7949 && is_std_init_list (non_reference (type
))
7950 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
7952 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
7953 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
7954 tree patparm
= get_pattern_parm (realparm
, tmpl
);
7955 tree pattype
= TREE_TYPE (patparm
);
7956 if (PACK_EXPANSION_P (pattype
))
7957 pattype
= PACK_EXPANSION_PATTERN (pattype
);
7958 pattype
= non_reference (pattype
);
7960 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
7961 && (cand
->explicit_targs
== NULL_TREE
7962 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
7963 <= TEMPLATE_TYPE_IDX (pattype
))))
7965 pedwarn (input_location
, 0, "deducing %qT as %qT",
7966 non_reference (TREE_TYPE (patparm
)),
7967 non_reference (type
));
7968 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
7969 " in call to %qD", cand
->fn
);
7970 pedwarn (input_location
, 0,
7971 " (you can disable this with -fno-deduce-init-list)");
7975 /* Set user_conv_p on the argument conversions, so rvalue/base handling
7976 knows not to allow any more UDCs. This needs to happen after we
7977 process cand->warnings. */
7978 if (flags
& LOOKUP_NO_CONVERSION
)
7979 conv
->user_conv_p
= true;
7981 tsubst_flags_t arg_complain
= complain
;
7982 if (!conversion_warning
)
7983 arg_complain
&= ~tf_warning
;
7985 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
7987 val
= convert_for_arg_passing (type
, val
, arg_complain
);
7989 if (val
== error_mark_node
)
7990 return error_mark_node
;
7992 argarray
[j
++] = val
;
7995 /* Default arguments */
7996 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
7998 if (TREE_VALUE (parm
) == error_mark_node
)
7999 return error_mark_node
;
8000 val
= convert_default_arg (TREE_VALUE (parm
),
8001 TREE_PURPOSE (parm
),
8004 if (val
== error_mark_node
)
8005 return error_mark_node
;
8006 argarray
[j
++] = val
;
8010 int magic
= magic_varargs_p (fn
);
8011 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8013 tree a
= (*args
)[arg_index
];
8014 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8016 /* Do no conversions for certain magic varargs. */
8017 a
= mark_type_use (a
);
8018 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8019 return error_mark_node
;
8021 else if (magic
!= 0)
8022 /* For other magic varargs only do decay_conversion. */
8023 a
= decay_conversion (a
, complain
);
8024 else if (DECL_CONSTRUCTOR_P (fn
)
8025 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8028 /* Avoid infinite recursion trying to call A(...). */
8029 if (complain
& tf_error
)
8030 /* Try to call the actual copy constructor for a good error. */
8031 call_copy_ctor (a
, complain
);
8032 return error_mark_node
;
8035 a
= convert_arg_to_ellipsis (a
, complain
);
8036 if (a
== error_mark_node
)
8037 return error_mark_node
;
8041 gcc_assert (j
<= nargs
);
8044 /* Avoid to do argument-transformation, if warnings for format, and for
8045 nonnull are disabled. Just in case that at least one of them is active
8046 the check_function_arguments function might warn about something. */
8048 bool warned_p
= false;
8051 || warn_suggest_attribute_format
8054 tree
*fargs
= (!nargs
? argarray
8055 : (tree
*) alloca (nargs
* sizeof (tree
)));
8056 for (j
= 0; j
< nargs
; j
++)
8058 /* For -Wformat undo the implicit passing by hidden reference
8059 done by convert_arg_to_ellipsis. */
8060 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8061 && TREE_CODE (TREE_TYPE (argarray
[j
])) == REFERENCE_TYPE
)
8062 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8064 fargs
[j
] = maybe_constant_value (argarray
[j
]);
8067 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8068 nargs
, fargs
, NULL
);
8071 if (DECL_INHERITED_CTOR (fn
))
8073 /* Check for passing ellipsis arguments to an inherited constructor. We
8074 could handle this by open-coding the inherited constructor rather than
8075 defining it, but let's not bother now. */
8076 if (!cp_unevaluated_operand
8078 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8080 if (complain
& tf_error
)
8082 sorry ("passing arguments to ellipsis of inherited constructor "
8084 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8086 return error_mark_node
;
8089 /* A base constructor inheriting from a virtual base doesn't get the
8090 inherited arguments, just this and __vtt. */
8091 if (ctor_omit_inherited_parms (fn
))
8095 /* Avoid actually calling copy constructors and copy assignment operators,
8098 if (! flag_elide_constructors
&& !force_elide
)
8099 /* Do things the hard way. */;
8100 else if (cand
->num_convs
== 1
8101 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8102 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8103 /* It's unsafe to elide the constructor when handling
8104 a noexcept-expression, it may evaluate to the wrong
8105 value (c++/53025). */
8106 && (force_elide
|| cp_noexcept_operand
== 0))
8109 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8111 bool trivial
= trivial_fn_p (fn
);
8113 /* Pull out the real argument, disregarding const-correctness. */
8115 /* Strip the reference binding for the constructor parameter. */
8116 if (CONVERT_EXPR_P (targ
)
8117 && TREE_CODE (TREE_TYPE (targ
)) == REFERENCE_TYPE
)
8118 targ
= TREE_OPERAND (targ
, 0);
8119 /* But don't strip any other reference bindings; binding a temporary to a
8120 reference prevents copy elision. */
8121 while ((CONVERT_EXPR_P (targ
)
8122 && TREE_CODE (TREE_TYPE (targ
)) != REFERENCE_TYPE
)
8123 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8124 targ
= TREE_OPERAND (targ
, 0);
8125 if (TREE_CODE (targ
) == ADDR_EXPR
)
8127 targ
= TREE_OPERAND (targ
, 0);
8128 if (!same_type_ignoring_top_level_qualifiers_p
8129 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8138 arg
= cp_build_fold_indirect_ref (arg
);
8140 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8142 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8143 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8145 /* It's from binding the ref parm to a packed field. */
8146 || convs
[0]->need_temporary_p
8148 /* See unsafe_copy_elision_p. */
8149 || DECL_BASE_CONSTRUCTOR_P (fn
));
8151 /* [class.copy]: the copy constructor is implicitly defined even if
8152 the implementation elided its use. */
8153 if (!trivial
&& !force_elide
)
8155 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8156 return error_mark_node
;
8157 already_used
= true;
8160 /* If we're creating a temp and we already have one, don't create a
8161 new one. If we're not creating a temp but we get one, use
8162 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8163 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8164 temp or an INIT_EXPR otherwise. */
8166 if (is_dummy_object (fa
))
8168 if (TREE_CODE (arg
) == TARGET_EXPR
)
8171 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8173 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8174 && !unsafe_copy_elision_p (fa
, arg
))
8176 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8178 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8182 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8183 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8184 && trivial_fn_p (fn
))
8186 tree to
= cp_stabilize_reference
8187 (cp_build_fold_indirect_ref (argarray
[0]));
8188 tree type
= TREE_TYPE (to
);
8189 tree as_base
= CLASSTYPE_AS_BASE (type
);
8190 tree arg
= argarray
[1];
8192 if (is_really_empty_class (type
))
8194 /* Avoid copying empty classes. */
8195 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8196 TREE_NO_WARNING (val
) = 1;
8198 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8200 arg
= cp_build_fold_indirect_ref (arg
);
8201 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8205 /* We must only copy the non-tail padding parts. */
8207 tree array_type
, alias_set
;
8209 arg2
= TYPE_SIZE_UNIT (as_base
);
8210 arg0
= cp_build_addr_expr (to
, complain
);
8212 array_type
= build_array_type (unsigned_char_type_node
,
8214 (size_binop (MINUS_EXPR
,
8215 arg2
, size_int (1))));
8216 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8217 t
= build2 (MODIFY_EXPR
, void_type_node
,
8218 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8219 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8220 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8221 TREE_NO_WARNING (val
) = 1;
8226 else if (trivial_fn_p (fn
))
8228 if (DECL_DESTRUCTOR_P (fn
))
8229 return fold_convert (void_type_node
, argarray
[0]);
8230 else if (default_ctor_p (fn
))
8232 if (is_dummy_object (argarray
[0]))
8233 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8234 no_cleanup_complain
);
8236 return cp_build_fold_indirect_ref (argarray
[0]);
8240 gcc_assert (!force_elide
);
8243 && !mark_used (fn
, complain
))
8244 return error_mark_node
;
8246 /* Warn if the built-in writes to an object of a non-trivial type. */
8247 if (warn_class_memaccess
8248 && vec_safe_length (args
) >= 2
8249 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8250 maybe_warn_class_memaccess (input_location
, fn
, args
);
8252 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0
8253 /* Don't mess with virtual lookup in instantiate_non_dependent_expr;
8254 virtual functions can't be constexpr. */
8255 && !in_template_function ())
8258 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8260 ba_any
, NULL
, complain
);
8261 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8263 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8265 if (TREE_SIDE_EFFECTS (argarray
[0]))
8266 argarray
[0] = save_expr (argarray
[0]);
8267 t
= build_pointer_type (TREE_TYPE (fn
));
8268 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8273 fn
= build_addr_func (fn
, complain
);
8274 if (fn
== error_mark_node
)
8275 return error_mark_node
;
8278 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8279 if (call
== error_mark_node
)
8281 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8283 tree c
= extract_call_expr (call
);
8284 /* build_new_op_1 will clear this when appropriate. */
8285 CALL_EXPR_ORDERED_ARGS (c
) = true;
8289 tree c
= extract_call_expr (call
);
8290 if (TREE_CODE (c
) == CALL_EXPR
)
8291 TREE_NO_WARNING (c
) = 1;
8299 /* Return the DECL of the first non-static subobject of class TYPE
8300 that satisfies the predicate PRED or null if none can be found. */
8302 template <class Predicate
>
8304 first_non_static_field (tree type
, Predicate pred
)
8306 if (!type
|| !CLASS_TYPE_P (type
))
8309 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8311 if (TREE_CODE (field
) != FIELD_DECL
)
8313 if (TREE_STATIC (field
))
8321 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8322 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8324 tree base
= TREE_TYPE (base_binfo
);
8327 if (tree field
= first_non_static_field (base
, pred
))
8334 struct NonPublicField
8336 bool operator() (const_tree t
)
8338 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8342 /* Return the DECL of the first non-public subobject of class TYPE
8343 or null if none can be found. */
8346 first_non_public_field (tree type
)
8348 return first_non_static_field (type
, NonPublicField ());
8351 struct NonTrivialField
8353 bool operator() (const_tree t
)
8355 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8359 /* Return the DECL of the first non-trivial subobject of class TYPE
8360 or null if none can be found. */
8363 first_non_trivial_field (tree type
)
8365 return first_non_static_field (type
, NonTrivialField ());
8368 } /* unnamed namespace */
8370 /* Return true if all copy and move assignment operator overloads for
8371 class TYPE are trivial and at least one of them is not deleted and,
8372 when ACCESS is set, accessible. Return false otherwise. Set
8373 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8374 copy or move assignment. */
8377 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8379 tree fns
= get_class_binding (type
, assign_op_identifier
);
8380 bool all_trivial
= true;
8382 /* Iterate over overloads of the assignment operator, checking
8383 accessible copy assignments for triviality. */
8385 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8389 /* Skip operators that aren't copy assignments. */
8393 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8394 || accessible_p (TYPE_BINFO (type
), f
, true));
8396 /* Skip template assignment operators and deleted functions. */
8397 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8403 if (!accessible
|| !trivial_fn_p (f
))
8404 all_trivial
= false;
8406 /* Break early when both properties have been determined. */
8407 if (*hasassign
&& !all_trivial
)
8411 /* Return true if they're all trivial and one of the expressions
8412 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8413 tree ref
= cp_build_reference_type (type
, false);
8415 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8416 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8419 /* Return true if all copy and move ctor overloads for class TYPE are
8420 trivial and at least one of them is not deleted and, when ACCESS is
8421 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8422 to true when the TYPE has a (not necessarily trivial) default and copy
8423 (or move) ctor, respectively. */
8426 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8428 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8429 bool all_trivial
= true;
8431 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8435 /* Skip template constructors. */
8436 if (TREE_CODE (f
) != FUNCTION_DECL
)
8439 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8441 /* Skip ctors other than default, copy, and move. */
8442 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8445 if (DECL_DELETED_FN (f
))
8448 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8449 || accessible_p (TYPE_BINFO (type
), f
, true));
8452 hasctor
[cpy_or_move_ctor_p
] = true;
8454 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8455 all_trivial
= false;
8457 /* Break early when both properties have been determined. */
8458 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8465 /* Issue a warning on a call to the built-in function FNDECL if it is
8466 a raw memory write whose destination is not an object of (something
8467 like) trivial or standard layout type with a non-deleted assignment
8468 and copy ctor. Detects const correctness violations, corrupting
8469 references, virtual table pointers, and bypassing non-trivial
8473 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8474 const vec
<tree
, va_gc
> *args
)
8476 /* Except for bcopy where it's second, the destination pointer is
8477 the first argument for all functions handled here. Compute
8478 the index of the destination and source arguments. */
8479 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8480 unsigned srcidx
= !dstidx
;
8482 tree dest
= (*args
)[dstidx
];
8483 if (!TREE_TYPE (dest
) || !POINTER_TYPE_P (TREE_TYPE (dest
)))
8486 tree srctype
= NULL_TREE
;
8488 /* Determine the type of the pointed-to object and whether it's
8489 a complete class type. */
8490 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8492 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8495 /* Check to see if the raw memory call is made by a non-static member
8496 function with THIS as the destination argument for the destination
8497 type. If so, and if the class has no non-trivial bases or members,
8498 be more permissive. */
8499 if (current_function_decl
8500 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8501 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8503 tree ctx
= DECL_CONTEXT (current_function_decl
);
8504 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8505 tree binfo
= TYPE_BINFO (ctx
);
8507 /* FIXME: The following if statement is overly permissive (see
8508 bug 84851). Remove it in GCC 9. */
8510 && !BINFO_VTABLE (binfo
)
8511 && !BINFO_N_BASE_BINFOS (binfo
)
8512 && (DECL_CONSTRUCTOR_P (current_function_decl
)
8513 || DECL_DESTRUCTOR_P (current_function_decl
)))
8517 && !BINFO_VTABLE (binfo
)
8518 && !first_non_trivial_field (desttype
))
8522 /* True if the class is trivial. */
8523 bool trivial
= trivial_type_p (desttype
);
8525 /* Set to true if DESTYPE has an accessible copy assignment. */
8526 bool hasassign
= false;
8527 /* True if all of the class' overloaded copy assignment operators
8528 are all trivial (and not deleted) and at least one of them is
8530 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8532 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8534 bool hasctors
[2] = { false, false };
8536 /* True if all of the class' overloaded copy constructors are all
8537 trivial (and not deleted) and at least one of them is accessible. */
8538 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8540 /* Set FLD to the first private/protected member of the class. */
8541 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8543 /* The warning format string. */
8544 const char *warnfmt
= NULL
;
8545 /* A suggested alternative to offer instead of the raw memory call.
8546 Empty string when none can be come up with. */
8547 const char *suggest
= "";
8548 bool warned
= false;
8550 switch (DECL_FUNCTION_CODE (fndecl
))
8552 case BUILT_IN_MEMSET
:
8553 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8555 /* Diagnose setting non-copy-assignable or non-trivial types,
8556 or types with a private member, to (potentially) non-zero
8557 bytes. Since the value of the bytes being written is unknown,
8558 suggest using assignment instead (if one exists). Also warn
8559 for writes into objects for which zero-initialization doesn't
8560 mean all bits clear (pointer-to-member data, where null is all
8561 bits set). Since the value being written is (most likely)
8562 non-zero, simply suggest assignment (but not copy assignment). */
8563 suggest
= "; use assignment instead";
8565 warnfmt
= G_("%qD writing to an object of type %#qT with "
8566 "no trivial copy-assignment");
8568 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8571 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8572 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8573 "%qD writing to an object of type %#qT with "
8575 fndecl
, desttype
, access
, fld
);
8577 else if (!zero_init_p (desttype
))
8578 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8579 "a pointer to data member%s");
8585 case BUILT_IN_BZERO
:
8586 /* Similarly to the above, diagnose clearing non-trivial or non-
8587 standard layout objects, or objects of types with no assignmenmt.
8588 Since the value being written is known to be zero, suggest either
8589 copy assignment, copy ctor, or default ctor as an alternative,
8590 depending on what's available. */
8592 if (hasassign
&& hasctors
[0])
8593 suggest
= G_("; use assignment or value-initialization instead");
8595 suggest
= G_("; use assignment instead");
8596 else if (hasctors
[0])
8597 suggest
= G_("; use value-initialization instead");
8600 warnfmt
= G_("%qD clearing an object of type %#qT with "
8601 "no trivial copy-assignment%s");
8603 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8604 else if (!zero_init_p (desttype
))
8605 warnfmt
= G_("%qD clearing an object of type %#qT containing "
8606 "a pointer-to-member%s");
8609 case BUILT_IN_BCOPY
:
8610 case BUILT_IN_MEMCPY
:
8611 case BUILT_IN_MEMMOVE
:
8612 case BUILT_IN_MEMPCPY
:
8613 /* Determine the type of the source object. */
8614 srctype
= TREE_TYPE ((*args
)[srcidx
]);
8615 if (!srctype
|| !POINTER_TYPE_P (srctype
))
8616 srctype
= void_type_node
;
8618 srctype
= TREE_TYPE (srctype
);
8620 /* Since it's impossible to determine wheter the byte copy is
8621 being used in place of assignment to an existing object or
8622 as a substitute for initialization, assume it's the former.
8623 Determine the best alternative to use instead depending on
8624 what's not deleted. */
8625 if (hasassign
&& hasctors
[1])
8626 suggest
= G_("; use copy-assignment or copy-initialization instead");
8628 suggest
= G_("; use copy-assignment instead");
8629 else if (hasctors
[1])
8630 suggest
= G_("; use copy-initialization instead");
8633 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
8634 "copy-assignment%s");
8635 else if (!trivially_copyable_p (desttype
))
8636 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
8639 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
8642 && !VOID_TYPE_P (srctype
)
8643 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8644 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8647 /* Warn when copying into a non-trivial object from an object
8648 of a different type other than void or char. */
8649 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8650 "%qD copying an object of non-trivial type "
8651 "%#qT from an array of %#qT",
8652 fndecl
, desttype
, srctype
);
8655 && !VOID_TYPE_P (srctype
)
8656 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8657 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8660 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8661 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8662 "%qD copying an object of type %#qT with "
8663 "%qs member %qD from an array of %#qT; use "
8664 "assignment or copy-initialization instead",
8665 fndecl
, desttype
, access
, fld
, srctype
);
8667 else if (!trivial
&& vec_safe_length (args
) > 2)
8669 tree sz
= maybe_constant_value ((*args
)[2]);
8670 if (!tree_fits_uhwi_p (sz
))
8673 /* Finally, warn on partial copies. */
8674 unsigned HOST_WIDE_INT typesize
8675 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
8676 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
8677 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8678 (typesize
- partial
> 1
8679 ? G_("%qD writing to an object of "
8680 "a non-trivial type %#qT leaves %wu "
8682 : G_("%qD writing to an object of "
8683 "a non-trivial type %#qT leaves %wu "
8685 fndecl
, desttype
, typesize
- partial
);
8689 case BUILT_IN_REALLOC
:
8691 if (!trivially_copyable_p (desttype
))
8692 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
8693 "%#qT; use %<new%> and %<delete%> instead");
8695 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
8696 "constructor; use %<new%> and %<delete%> instead");
8697 else if (!get_dtor (desttype
, tf_none
))
8698 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
8702 tree sz
= maybe_constant_value ((*args
)[1]);
8703 if (TREE_CODE (sz
) == INTEGER_CST
8704 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
8705 /* Finally, warn on reallocation into insufficient space. */
8706 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8707 "%qD moving an object of non-trivial type "
8708 "%#qT and size %E into a region of size %E",
8709 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
8721 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8722 warnfmt
, fndecl
, desttype
, suggest
);
8724 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8725 warnfmt
, fndecl
, desttype
);
8729 inform (location_of (desttype
), "%#qT declared here", desttype
);
8732 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
8733 This function performs no overload resolution, conversion, or other
8734 high-level operations. */
8737 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
8738 tsubst_flags_t complain
)
8742 /* Remember roughly where this call is. */
8743 location_t loc
= EXPR_LOC_OR_LOC (fn
, input_location
);
8744 fn
= build_call_a (fn
, nargs
, argarray
);
8745 SET_EXPR_LOCATION (fn
, loc
);
8747 fndecl
= get_callee_fndecl (fn
);
8749 /* Check that arguments to builtin functions match the expectations. */
8751 && DECL_BUILT_IN (fndecl
)
8752 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
)
8756 /* We need to take care that values to BUILT_IN_NORMAL
8758 for (i
= 0; i
< nargs
; i
++)
8759 argarray
[i
] = fold_non_dependent_expr (argarray
[i
]);
8761 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
8763 return error_mark_node
;
8766 if (VOID_TYPE_P (TREE_TYPE (fn
)))
8769 /* 5.2.2/11: If a function call is a prvalue of object type: if the
8770 function call is either the operand of a decltype-specifier or the
8771 right operand of a comma operator that is the operand of a
8772 decltype-specifier, a temporary object is not introduced for the
8773 prvalue. The type of the prvalue may be incomplete. */
8774 if (!(complain
& tf_decltype
))
8776 fn
= require_complete_type_sfinae (fn
, complain
);
8777 if (fn
== error_mark_node
)
8778 return error_mark_node
;
8780 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
8782 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
8783 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
8786 return convert_from_reference (fn
);
8789 /* Returns the value to use for the in-charge parameter when making a
8790 call to a function with the indicated NAME.
8792 FIXME:Can't we find a neater way to do this mapping? */
8795 in_charge_arg_for_name (tree name
)
8797 if (IDENTIFIER_CTOR_P (name
))
8799 if (name
== complete_ctor_identifier
)
8800 return integer_one_node
;
8801 gcc_checking_assert (name
== base_ctor_identifier
);
8805 if (name
== complete_dtor_identifier
)
8806 return integer_two_node
;
8807 else if (name
== deleting_dtor_identifier
)
8808 return integer_three_node
;
8809 gcc_checking_assert (name
== base_dtor_identifier
);
8812 return integer_zero_node
;
8815 /* We've built up a constructor call RET. Complain if it delegates to the
8816 constructor we're currently compiling. */
8819 check_self_delegation (tree ret
)
8821 if (TREE_CODE (ret
) == TARGET_EXPR
)
8822 ret
= TARGET_EXPR_INITIAL (ret
);
8823 tree fn
= cp_get_callee_fndecl_nofold (ret
);
8824 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
8825 error ("constructor delegates to itself");
8828 /* Build a call to a constructor, destructor, or an assignment
8829 operator for INSTANCE, an expression with class type. NAME
8830 indicates the special member function to call; *ARGS are the
8831 arguments. ARGS may be NULL. This may change ARGS. BINFO
8832 indicates the base of INSTANCE that is to be passed as the `this'
8833 parameter to the member function called.
8835 FLAGS are the LOOKUP_* flags to use when processing the call.
8837 If NAME indicates a complete object constructor, INSTANCE may be
8838 NULL_TREE. In this case, the caller will call build_cplus_new to
8839 store the newly constructed object into a VAR_DECL. */
8842 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
8843 tree binfo
, int flags
, tsubst_flags_t complain
)
8846 /* The type of the subobject to be constructed or destroyed. */
8848 vec
<tree
, va_gc
> *allocated
= NULL
;
8851 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
8854 /* Resolve the name. */
8855 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
8856 return error_mark_node
;
8858 binfo
= TYPE_BINFO (binfo
);
8861 gcc_assert (binfo
!= NULL_TREE
);
8863 class_type
= BINFO_TYPE (binfo
);
8865 /* Handle the special case where INSTANCE is NULL_TREE. */
8866 if (name
== complete_ctor_identifier
&& !instance
)
8867 instance
= build_dummy_object (class_type
);
8870 if (IDENTIFIER_DTOR_P (name
))
8871 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
8873 /* Convert to the base class, if necessary. */
8874 if (!same_type_ignoring_top_level_qualifiers_p
8875 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
8877 if (IDENTIFIER_CDTOR_P (name
))
8878 /* For constructors and destructors, either the base is
8879 non-virtual, or it is virtual but we are doing the
8880 conversion from a constructor or destructor for the
8881 complete object. In either case, we can convert
8883 instance
= convert_to_base_statically (instance
, binfo
);
8886 /* However, for assignment operators, we must convert
8887 dynamically if the base is virtual. */
8888 gcc_checking_assert (name
== assign_op_identifier
);
8889 instance
= build_base_path (PLUS_EXPR
, instance
,
8890 binfo
, /*nonnull=*/1, complain
);
8895 gcc_assert (instance
!= NULL_TREE
);
8897 /* In C++17, "If the initializer expression is a prvalue and the
8898 cv-unqualified version of the source type is the same class as the class
8899 of the destination, the initializer expression is used to initialize the
8900 destination object." Handle that here to avoid doing overload
8902 if (cxx_dialect
>= cxx17
8903 && args
&& vec_safe_length (*args
) == 1
8904 && name
== complete_ctor_identifier
)
8906 tree arg
= (**args
)[0];
8908 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
8909 && !TYPE_HAS_LIST_CTOR (class_type
)
8910 && CONSTRUCTOR_NELTS (arg
) == 1)
8911 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
8913 if ((TREE_CODE (arg
) == TARGET_EXPR
8914 || TREE_CODE (arg
) == CONSTRUCTOR
)
8915 && (same_type_ignoring_top_level_qualifiers_p
8916 (class_type
, TREE_TYPE (arg
))))
8918 if (is_dummy_object (instance
))
8920 else if (TREE_CODE (arg
) == TARGET_EXPR
)
8921 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
8923 if ((complain
& tf_error
)
8924 && (flags
& LOOKUP_DELEGATING_CONS
))
8925 check_self_delegation (arg
);
8926 /* Avoid change of behavior on Wunused-var-2.C. */
8927 instance
= mark_lvalue_use (instance
);
8928 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
8932 fns
= lookup_fnfields (binfo
, name
, 1);
8934 /* When making a call to a constructor or destructor for a subobject
8935 that uses virtual base classes, pass down a pointer to a VTT for
8937 if ((name
== base_ctor_identifier
8938 || name
== base_dtor_identifier
)
8939 && CLASSTYPE_VBASECLASSES (class_type
))
8944 /* If the current function is a complete object constructor
8945 or destructor, then we fetch the VTT directly.
8946 Otherwise, we look it up using the VTT we were given. */
8947 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
8948 vtt
= decay_conversion (vtt
, complain
);
8949 if (vtt
== error_mark_node
)
8950 return error_mark_node
;
8951 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
8952 if (BINFO_SUBVTT_INDEX (binfo
))
8953 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
8959 allocated
= make_tree_vector ();
8963 vec_safe_insert (*args
, 0, sub_vtt
);
8966 ret
= build_new_method_call (instance
, fns
, args
,
8967 TYPE_BINFO (BINFO_TYPE (binfo
)),
8971 if (allocated
!= NULL
)
8972 release_tree_vector (allocated
);
8974 if ((complain
& tf_error
)
8975 && (flags
& LOOKUP_DELEGATING_CONS
)
8976 && name
== complete_ctor_identifier
)
8977 check_self_delegation (ret
);
8982 /* Return the NAME, as a C string. The NAME indicates a function that
8983 is a member of TYPE. *FREE_P is set to true if the caller must
8984 free the memory returned.
8986 Rather than go through all of this, we should simply set the names
8987 of constructors and destructors appropriately, and dispense with
8988 ctor_identifier, dtor_identifier, etc. */
8991 name_as_c_string (tree name
, tree type
, bool *free_p
)
8993 const char *pretty_name
;
8995 /* Assume that we will not allocate memory. */
8997 /* Constructors and destructors are special. */
8998 if (IDENTIFIER_CDTOR_P (name
))
9001 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9002 /* For a destructor, add the '~'. */
9003 if (IDENTIFIER_DTOR_P (name
))
9005 pretty_name
= concat ("~", pretty_name
, NULL
);
9006 /* Remember that we need to free the memory allocated. */
9010 else if (IDENTIFIER_CONV_OP_P (name
))
9012 pretty_name
= concat ("operator ",
9013 type_as_string_translate (TREE_TYPE (name
),
9014 TFF_PLAIN_IDENTIFIER
),
9016 /* Remember that we need to free the memory allocated. */
9020 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9022 return CONST_CAST (char *, pretty_name
);
9025 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9026 be set, upon return, to the function called. ARGS may be NULL.
9027 This may change ARGS. */
9030 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9031 tree conversion_path
, int flags
,
9032 tree
*fn_p
, tsubst_flags_t complain
)
9034 struct z_candidate
*candidates
= 0, *cand
;
9035 tree explicit_targs
= NULL_TREE
;
9036 tree basetype
= NULL_TREE
;
9037 tree access_binfo
, binfo
;
9039 tree first_mem_arg
= NULL_TREE
;
9041 bool skip_first_for_error
;
9042 vec
<tree
, va_gc
> *user_args
;
9045 int template_only
= 0;
9049 vec
<tree
, va_gc
> *orig_args
= NULL
;
9052 gcc_assert (instance
!= NULL_TREE
);
9054 /* We don't know what function we're going to call, yet. */
9058 if (error_operand_p (instance
)
9059 || !fns
|| error_operand_p (fns
))
9060 return error_mark_node
;
9062 if (!BASELINK_P (fns
))
9064 if (complain
& tf_error
)
9065 error ("call to non-function %qD", fns
);
9066 return error_mark_node
;
9069 orig_instance
= instance
;
9072 /* Dismantle the baselink to collect all the information we need. */
9073 if (!conversion_path
)
9074 conversion_path
= BASELINK_BINFO (fns
);
9075 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9076 binfo
= BASELINK_BINFO (fns
);
9077 optype
= BASELINK_OPTYPE (fns
);
9078 fns
= BASELINK_FUNCTIONS (fns
);
9079 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9081 explicit_targs
= TREE_OPERAND (fns
, 1);
9082 fns
= TREE_OPERAND (fns
, 0);
9085 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
9086 || TREE_CODE (fns
) == TEMPLATE_DECL
9087 || TREE_CODE (fns
) == OVERLOAD
);
9088 fn
= OVL_FIRST (fns
);
9089 name
= DECL_NAME (fn
);
9091 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9092 gcc_assert (CLASS_TYPE_P (basetype
));
9094 if (processing_template_decl
)
9096 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9097 instance
= build_non_dependent_expr (instance
);
9099 make_args_non_dependent (*args
);
9102 user_args
= args
== NULL
? NULL
: *args
;
9103 /* Under DR 147 A::A() is an invalid constructor call,
9104 not a functional cast. */
9105 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9107 if (! (complain
& tf_error
))
9108 return error_mark_node
;
9110 basetype
= DECL_CONTEXT (fn
);
9111 name
= constructor_name (basetype
);
9112 if (permerror (input_location
,
9113 "cannot call constructor %<%T::%D%> directly",
9115 inform (input_location
, "for a function-style cast, remove the "
9116 "redundant %<::%D%>", name
);
9117 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9122 /* Process the argument list. */
9123 if (args
!= NULL
&& *args
!= NULL
)
9125 *args
= resolve_args (*args
, complain
);
9127 return error_mark_node
;
9130 /* Consider the object argument to be used even if we end up selecting a
9131 static member function. */
9132 instance
= mark_type_use (instance
);
9134 /* Figure out whether to skip the first argument for the error
9135 message we will display to users if an error occurs. We don't
9136 want to display any compiler-generated arguments. The "this"
9137 pointer hasn't been added yet. However, we must remove the VTT
9138 pointer if this is a call to a base-class constructor or
9140 skip_first_for_error
= false;
9141 if (IDENTIFIER_CDTOR_P (name
))
9143 /* Callers should explicitly indicate whether they want to ctor
9144 the complete object or just the part without virtual bases. */
9145 gcc_assert (name
!= ctor_identifier
);
9147 /* Remove the VTT pointer, if present. */
9148 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9149 && CLASSTYPE_VBASECLASSES (basetype
))
9150 skip_first_for_error
= true;
9152 /* It's OK to call destructors and constructors on cv-qualified
9153 objects. Therefore, convert the INSTANCE to the unqualified
9154 type, if necessary. */
9155 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9157 instance
= build_this (instance
);
9158 instance
= build_nop (build_pointer_type (basetype
), instance
);
9159 instance
= build_fold_indirect_ref (instance
);
9163 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9165 /* For the overload resolution we need to find the actual `this`
9166 that would be captured if the call turns out to be to a
9167 non-static member function. Do not actually capture it at this
9169 if (DECL_CONSTRUCTOR_P (fn
))
9170 /* Constructors don't use the enclosing 'this'. */
9171 first_mem_arg
= instance
;
9173 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9175 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9176 p
= conversion_obstack_alloc (0);
9178 /* The number of arguments artificial parms in ARGS; we subtract one because
9179 there's no 'this' in ARGS. */
9180 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9182 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9183 initializer, not T({ }). */
9184 if (DECL_CONSTRUCTOR_P (fn
)
9185 && vec_safe_length (user_args
) > skip
9186 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9188 tree init_list
= (*user_args
)[skip
];
9189 tree init
= NULL_TREE
;
9191 gcc_assert (user_args
->length () == skip
+ 1
9192 && !(flags
& LOOKUP_ONLYCONVERTING
));
9194 /* If the initializer list has no elements and T is a class type with
9195 a default constructor, the object is value-initialized. Handle
9196 this here so we don't need to handle it wherever we use
9197 build_special_member_call. */
9198 if (CONSTRUCTOR_NELTS (init_list
) == 0
9199 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9200 /* For a user-provided default constructor, use the normal
9201 mechanisms so that protected access works. */
9202 && type_has_non_user_provided_default_constructor (basetype
)
9203 && !processing_template_decl
)
9204 init
= build_value_init (basetype
, complain
);
9206 /* If BASETYPE is an aggregate, we need to do aggregate
9208 else if (CP_AGGREGATE_TYPE_P (basetype
))
9210 init
= reshape_init (basetype
, init_list
, complain
);
9211 init
= digest_init (basetype
, init
, complain
);
9216 if (is_dummy_object (instance
))
9217 return get_target_expr_sfinae (init
, complain
);
9218 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9219 TREE_SIDE_EFFECTS (init
) = true;
9223 /* Otherwise go ahead with overload resolution. */
9224 add_list_candidates (fns
, first_mem_arg
, user_args
,
9225 basetype
, explicit_targs
, template_only
,
9226 conversion_path
, access_binfo
, flags
,
9227 &candidates
, complain
);
9230 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9231 explicit_targs
, template_only
, conversion_path
,
9232 access_binfo
, flags
, &candidates
, complain
);
9234 any_viable_p
= false;
9235 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9239 if (complain
& tf_error
)
9241 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9242 cxx_incomplete_type_error (instance
, basetype
);
9244 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9245 basetype
, optype
, build_tree_list_vec (user_args
),
9246 TREE_TYPE (instance
));
9249 tree arglist
= build_tree_list_vec (user_args
);
9250 tree errname
= name
;
9251 bool twiddle
= false;
9252 if (IDENTIFIER_CDTOR_P (errname
))
9254 twiddle
= IDENTIFIER_DTOR_P (errname
);
9255 errname
= constructor_name (basetype
);
9258 errname
= lookup_template_function (errname
, explicit_targs
);
9259 if (skip_first_for_error
)
9260 arglist
= TREE_CHAIN (arglist
);
9261 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9262 basetype
, &"~"[!twiddle
], errname
, arglist
,
9263 TREE_TYPE (instance
));
9265 print_z_candidates (location_of (name
), candidates
);
9267 call
= error_mark_node
;
9271 cand
= tourney (candidates
, complain
);
9278 if (complain
& tf_error
)
9280 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9281 arglist
= build_tree_list_vec (user_args
);
9282 if (skip_first_for_error
)
9283 arglist
= TREE_CHAIN (arglist
);
9284 if (!any_strictly_viable (candidates
))
9285 error ("no matching function for call to %<%s(%A)%>",
9286 pretty_name
, arglist
);
9288 error ("call of overloaded %<%s(%A)%> is ambiguous",
9289 pretty_name
, arglist
);
9290 print_z_candidates (location_of (name
), candidates
);
9294 call
= error_mark_node
;
9301 if (!(flags
& LOOKUP_NONVIRTUAL
)
9302 && DECL_PURE_VIRTUAL_P (fn
)
9303 && instance
== current_class_ref
9304 && (complain
& tf_warning
))
9306 /* This is not an error, it is runtime undefined
9308 if (!current_function_decl
)
9309 warning (0, "pure virtual %q#D called from "
9310 "non-static data member initializer", fn
);
9311 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9312 || DECL_DESTRUCTOR_P (current_function_decl
))
9313 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9314 ? G_("pure virtual %q#D called from constructor")
9315 : G_("pure virtual %q#D called from destructor")),
9319 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9320 && !DECL_CONSTRUCTOR_P (fn
)
9321 && is_dummy_object (instance
))
9323 instance
= maybe_resolve_dummy (instance
, true);
9324 if (instance
== error_mark_node
)
9325 call
= error_mark_node
;
9326 else if (!is_dummy_object (instance
))
9328 /* We captured 'this' in the current lambda now that
9329 we know we really need it. */
9330 cand
->first_arg
= instance
;
9332 else if (any_dependent_bases_p ())
9333 /* We can't tell until instantiation time whether we can use
9334 *this as the implicit object argument. */;
9337 if (complain
& tf_error
)
9338 error ("cannot call member function %qD without object",
9340 call
= error_mark_node
;
9344 if (call
!= error_mark_node
)
9346 /* Optimize away vtable lookup if we know that this
9347 function can't be overridden. We need to check if
9348 the context and the type where we found fn are the same,
9349 actually FN might be defined in a different class
9350 type because of a using-declaration. In this case, we
9351 do not want to perform a non-virtual call. */
9352 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9353 && same_type_ignoring_top_level_qualifiers_p
9354 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9355 && resolves_to_fixed_type_p (instance
, 0))
9356 flags
|= LOOKUP_NONVIRTUAL
;
9358 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9359 /* Now we know what function is being called. */
9362 /* Build the actual CALL_EXPR. */
9363 call
= build_over_call (cand
, flags
, complain
);
9364 /* In an expression of the form `a->f()' where `f' turns
9365 out to be a static member function, `a' is
9366 none-the-less evaluated. */
9367 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9368 && !is_dummy_object (instance
)
9369 && TREE_SIDE_EFFECTS (instance
))
9371 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9374 if (TREE_THIS_VOLATILE (a
))
9376 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9378 else if (call
!= error_mark_node
9379 && DECL_DESTRUCTOR_P (cand
->fn
)
9380 && !VOID_TYPE_P (TREE_TYPE (call
)))
9381 /* An explicit call of the form "x->~X()" has type
9382 "void". However, on platforms where destructors
9383 return "this" (i.e., those where
9384 targetm.cxx.cdtor_returns_this is true), such calls
9385 will appear to have a return value of pointer type
9386 to the low-level call machinery. We do not want to
9387 change the low-level machinery, since we want to be
9388 able to optimize "delete f()" on such platforms as
9389 "operator delete(~X(f()))" (rather than generating
9390 "t = f(), ~X(t), operator delete (t)"). */
9391 call
= build_nop (void_type_node
, call
);
9396 if (processing_template_decl
&& call
!= error_mark_node
)
9398 bool cast_to_void
= false;
9400 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9401 call
= TREE_OPERAND (call
, 1);
9402 else if (TREE_CODE (call
) == NOP_EXPR
)
9404 cast_to_void
= true;
9405 call
= TREE_OPERAND (call
, 0);
9407 if (INDIRECT_REF_P (call
))
9408 call
= TREE_OPERAND (call
, 0);
9409 call
= (build_min_non_dep_call_vec
9411 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9412 orig_instance
, orig_fns
, NULL_TREE
),
9414 SET_EXPR_LOCATION (call
, input_location
);
9415 call
= convert_from_reference (call
);
9417 call
= build_nop (void_type_node
, call
);
9420 /* Free all the conversions we allocated. */
9421 obstack_free (&conversion_obstack
, p
);
9423 if (orig_args
!= NULL
)
9424 release_tree_vector (orig_args
);
9429 /* Wrapper for above. */
9432 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9433 tree conversion_path
, int flags
,
9434 tree
*fn_p
, tsubst_flags_t complain
)
9437 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9438 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9440 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9444 /* Returns true iff standard conversion sequence ICS1 is a proper
9445 subsequence of ICS2. */
9448 is_subseq (conversion
*ics1
, conversion
*ics2
)
9450 /* We can assume that a conversion of the same code
9451 between the same types indicates a subsequence since we only get
9452 here if the types we are converting from are the same. */
9454 while (ics1
->kind
== ck_rvalue
9455 || ics1
->kind
== ck_lvalue
)
9456 ics1
= next_conversion (ics1
);
9460 while (ics2
->kind
== ck_rvalue
9461 || ics2
->kind
== ck_lvalue
)
9462 ics2
= next_conversion (ics2
);
9464 if (ics2
->kind
== ck_user
9465 || ics2
->kind
== ck_ambig
9466 || ics2
->kind
== ck_aggr
9467 || ics2
->kind
== ck_list
9468 || ics2
->kind
== ck_identity
)
9469 /* At this point, ICS1 cannot be a proper subsequence of
9470 ICS2. We can get a USER_CONV when we are comparing the
9471 second standard conversion sequence of two user conversion
9475 ics2
= next_conversion (ics2
);
9477 while (ics2
->kind
== ck_rvalue
9478 || ics2
->kind
== ck_lvalue
)
9479 ics2
= next_conversion (ics2
);
9481 if (ics2
->kind
== ics1
->kind
9482 && same_type_p (ics2
->type
, ics1
->type
)
9483 && (ics1
->kind
== ck_identity
9484 || same_type_p (next_conversion (ics2
)->type
,
9485 next_conversion (ics1
)->type
)))
9490 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9491 be any _TYPE nodes. */
9494 is_properly_derived_from (tree derived
, tree base
)
9496 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
9499 /* We only allow proper derivation here. The DERIVED_FROM_P macro
9500 considers every class derived from itself. */
9501 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
9502 && DERIVED_FROM_P (base
, derived
));
9505 /* We build the ICS for an implicit object parameter as a pointer
9506 conversion sequence. However, such a sequence should be compared
9507 as if it were a reference conversion sequence. If ICS is the
9508 implicit conversion sequence for an implicit object parameter,
9509 modify it accordingly. */
9512 maybe_handle_implicit_object (conversion
**ics
)
9516 /* [over.match.funcs]
9518 For non-static member functions, the type of the
9519 implicit object parameter is "reference to cv X"
9520 where X is the class of which the function is a
9521 member and cv is the cv-qualification on the member
9522 function declaration. */
9523 conversion
*t
= *ics
;
9524 tree reference_type
;
9526 /* The `this' parameter is a pointer to a class type. Make the
9527 implicit conversion talk about a reference to that same class
9529 reference_type
= TREE_TYPE (t
->type
);
9530 reference_type
= build_reference_type (reference_type
);
9532 if (t
->kind
== ck_qual
)
9533 t
= next_conversion (t
);
9534 if (t
->kind
== ck_ptr
)
9535 t
= next_conversion (t
);
9536 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
9537 t
= direct_reference_binding (reference_type
, t
);
9539 t
->rvaluedness_matches_p
= 0;
9544 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
9545 and return the initial reference binding conversion. Otherwise,
9546 leave *ICS unchanged and return NULL. */
9549 maybe_handle_ref_bind (conversion
**ics
)
9551 if ((*ics
)->kind
== ck_ref_bind
)
9553 conversion
*old_ics
= *ics
;
9554 *ics
= next_conversion (old_ics
);
9555 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
9562 /* Compare two implicit conversion sequences according to the rules set out in
9563 [over.ics.rank]. Return values:
9565 1: ics1 is better than ics2
9566 -1: ics2 is better than ics1
9567 0: ics1 and ics2 are indistinguishable */
9570 compare_ics (conversion
*ics1
, conversion
*ics2
)
9576 tree deref_from_type1
= NULL_TREE
;
9577 tree deref_from_type2
= NULL_TREE
;
9578 tree deref_to_type1
= NULL_TREE
;
9579 tree deref_to_type2
= NULL_TREE
;
9580 conversion_rank rank1
, rank2
;
9582 /* REF_BINDING is nonzero if the result of the conversion sequence
9583 is a reference type. In that case REF_CONV is the reference
9584 binding conversion. */
9585 conversion
*ref_conv1
;
9586 conversion
*ref_conv2
;
9588 /* Compare badness before stripping the reference conversion. */
9589 if (ics1
->bad_p
> ics2
->bad_p
)
9591 else if (ics1
->bad_p
< ics2
->bad_p
)
9594 /* Handle implicit object parameters. */
9595 maybe_handle_implicit_object (&ics1
);
9596 maybe_handle_implicit_object (&ics2
);
9598 /* Handle reference parameters. */
9599 ref_conv1
= maybe_handle_ref_bind (&ics1
);
9600 ref_conv2
= maybe_handle_ref_bind (&ics2
);
9602 /* List-initialization sequence L1 is a better conversion sequence than
9603 list-initialization sequence L2 if L1 converts to
9604 std::initializer_list<X> for some X and L2 does not. */
9605 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
9607 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
9612 When comparing the basic forms of implicit conversion sequences (as
9613 defined in _over.best.ics_)
9615 --a standard conversion sequence (_over.ics.scs_) is a better
9616 conversion sequence than a user-defined conversion sequence
9617 or an ellipsis conversion sequence, and
9619 --a user-defined conversion sequence (_over.ics.user_) is a
9620 better conversion sequence than an ellipsis conversion sequence
9621 (_over.ics.ellipsis_). */
9622 /* Use BAD_CONVERSION_RANK because we already checked for a badness
9623 mismatch. If both ICS are bad, we try to make a decision based on
9624 what would have happened if they'd been good. This is not an
9625 extension, we'll still give an error when we build up the call; this
9626 just helps us give a more helpful error message. */
9627 rank1
= BAD_CONVERSION_RANK (ics1
);
9628 rank2
= BAD_CONVERSION_RANK (ics2
);
9632 else if (rank1
< rank2
)
9635 if (ics1
->ellipsis_p
)
9636 /* Both conversions are ellipsis conversions. */
9639 /* User-defined conversion sequence U1 is a better conversion sequence
9640 than another user-defined conversion sequence U2 if they contain the
9641 same user-defined conversion operator or constructor and if the sec-
9642 ond standard conversion sequence of U1 is better than the second
9643 standard conversion sequence of U2. */
9645 /* Handle list-conversion with the same code even though it isn't always
9646 ranked as a user-defined conversion and it doesn't have a second
9647 standard conversion sequence; it will still have the desired effect.
9648 Specifically, we need to do the reference binding comparison at the
9649 end of this function. */
9651 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
|| ics1
->kind
== ck_aggr
)
9656 for (t1
= ics1
; t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
9657 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
9658 || t1
->kind
== ck_list
)
9660 for (t2
= ics2
; t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
9661 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
9662 || t2
->kind
== ck_list
)
9665 if (t1
->kind
!= t2
->kind
)
9667 else if (t1
->kind
== ck_user
)
9669 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
9670 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
9676 /* For ambiguous or aggregate conversions, use the target type as
9677 a proxy for the conversion function. */
9678 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
9682 /* We can just fall through here, after setting up
9683 FROM_TYPE1 and FROM_TYPE2. */
9684 from_type1
= t1
->type
;
9685 from_type2
= t2
->type
;
9692 /* We're dealing with two standard conversion sequences.
9696 Standard conversion sequence S1 is a better conversion
9697 sequence than standard conversion sequence S2 if
9699 --S1 is a proper subsequence of S2 (comparing the conversion
9700 sequences in the canonical form defined by _over.ics.scs_,
9701 excluding any Lvalue Transformation; the identity
9702 conversion sequence is considered to be a subsequence of
9703 any non-identity conversion sequence */
9706 while (t1
->kind
!= ck_identity
)
9707 t1
= next_conversion (t1
);
9708 from_type1
= t1
->type
;
9711 while (t2
->kind
!= ck_identity
)
9712 t2
= next_conversion (t2
);
9713 from_type2
= t2
->type
;
9716 /* One sequence can only be a subsequence of the other if they start with
9717 the same type. They can start with different types when comparing the
9718 second standard conversion sequence in two user-defined conversion
9720 if (same_type_p (from_type1
, from_type2
))
9722 if (is_subseq (ics1
, ics2
))
9724 if (is_subseq (ics2
, ics1
))
9732 --the rank of S1 is better than the rank of S2 (by the rules
9735 Standard conversion sequences are ordered by their ranks: an Exact
9736 Match is a better conversion than a Promotion, which is a better
9737 conversion than a Conversion.
9739 Two conversion sequences with the same rank are indistinguishable
9740 unless one of the following rules applies:
9742 --A conversion that does not a convert a pointer, pointer to member,
9743 or std::nullptr_t to bool is better than one that does.
9745 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
9746 so that we do not have to check it explicitly. */
9747 if (ics1
->rank
< ics2
->rank
)
9749 else if (ics2
->rank
< ics1
->rank
)
9752 to_type1
= ics1
->type
;
9753 to_type2
= ics2
->type
;
9755 /* A conversion from scalar arithmetic type to complex is worse than a
9756 conversion between scalar arithmetic types. */
9757 if (same_type_p (from_type1
, from_type2
)
9758 && ARITHMETIC_TYPE_P (from_type1
)
9759 && ARITHMETIC_TYPE_P (to_type1
)
9760 && ARITHMETIC_TYPE_P (to_type2
)
9761 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
9762 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
9764 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
9770 if (TYPE_PTR_P (from_type1
)
9771 && TYPE_PTR_P (from_type2
)
9772 && TYPE_PTR_P (to_type1
)
9773 && TYPE_PTR_P (to_type2
))
9775 deref_from_type1
= TREE_TYPE (from_type1
);
9776 deref_from_type2
= TREE_TYPE (from_type2
);
9777 deref_to_type1
= TREE_TYPE (to_type1
);
9778 deref_to_type2
= TREE_TYPE (to_type2
);
9780 /* The rules for pointers to members A::* are just like the rules
9781 for pointers A*, except opposite: if B is derived from A then
9782 A::* converts to B::*, not vice versa. For that reason, we
9783 switch the from_ and to_ variables here. */
9784 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
9785 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
9786 || (TYPE_PTRMEMFUNC_P (from_type1
)
9787 && TYPE_PTRMEMFUNC_P (from_type2
)
9788 && TYPE_PTRMEMFUNC_P (to_type1
)
9789 && TYPE_PTRMEMFUNC_P (to_type2
)))
9791 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
9792 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
9793 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
9794 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
9797 if (deref_from_type1
!= NULL_TREE
9798 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
9799 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
9801 /* This was one of the pointer or pointer-like conversions.
9805 --If class B is derived directly or indirectly from class A,
9806 conversion of B* to A* is better than conversion of B* to
9807 void*, and conversion of A* to void* is better than
9808 conversion of B* to void*. */
9809 if (VOID_TYPE_P (deref_to_type1
)
9810 && VOID_TYPE_P (deref_to_type2
))
9812 if (is_properly_derived_from (deref_from_type1
,
9815 else if (is_properly_derived_from (deref_from_type2
,
9819 else if (VOID_TYPE_P (deref_to_type1
)
9820 || VOID_TYPE_P (deref_to_type2
))
9822 if (same_type_p (deref_from_type1
, deref_from_type2
))
9824 if (VOID_TYPE_P (deref_to_type2
))
9826 if (is_properly_derived_from (deref_from_type1
,
9830 /* We know that DEREF_TO_TYPE1 is `void' here. */
9831 else if (is_properly_derived_from (deref_from_type1
,
9836 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
9837 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
9841 --If class B is derived directly or indirectly from class A
9842 and class C is derived directly or indirectly from B,
9844 --conversion of C* to B* is better than conversion of C* to
9847 --conversion of B* to A* is better than conversion of C* to
9849 if (same_type_p (deref_from_type1
, deref_from_type2
))
9851 if (is_properly_derived_from (deref_to_type1
,
9854 else if (is_properly_derived_from (deref_to_type2
,
9858 else if (same_type_p (deref_to_type1
, deref_to_type2
))
9860 if (is_properly_derived_from (deref_from_type2
,
9863 else if (is_properly_derived_from (deref_from_type1
,
9869 else if (CLASS_TYPE_P (non_reference (from_type1
))
9870 && same_type_p (from_type1
, from_type2
))
9872 tree from
= non_reference (from_type1
);
9876 --binding of an expression of type C to a reference of type
9877 B& is better than binding an expression of type C to a
9878 reference of type A&
9880 --conversion of C to B is better than conversion of C to A, */
9881 if (is_properly_derived_from (from
, to_type1
)
9882 && is_properly_derived_from (from
, to_type2
))
9884 if (is_properly_derived_from (to_type1
, to_type2
))
9886 else if (is_properly_derived_from (to_type2
, to_type1
))
9890 else if (CLASS_TYPE_P (non_reference (to_type1
))
9891 && same_type_p (to_type1
, to_type2
))
9893 tree to
= non_reference (to_type1
);
9897 --binding of an expression of type B to a reference of type
9898 A& is better than binding an expression of type C to a
9899 reference of type A&,
9901 --conversion of B to A is better than conversion of C to A */
9902 if (is_properly_derived_from (from_type1
, to
)
9903 && is_properly_derived_from (from_type2
, to
))
9905 if (is_properly_derived_from (from_type2
, from_type1
))
9907 else if (is_properly_derived_from (from_type1
, from_type2
))
9914 --S1 and S2 differ only in their qualification conversion and yield
9915 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
9916 qualification signature of type T1 is a proper subset of the cv-
9917 qualification signature of type T2 */
9918 if (ics1
->kind
== ck_qual
9919 && ics2
->kind
== ck_qual
9920 && same_type_p (from_type1
, from_type2
))
9922 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
9929 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
9930 to an implicit object parameter of a non-static member function
9931 declared without a ref-qualifier, and either S1 binds an lvalue
9932 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
9933 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
9934 draft standard, 13.3.3.2)
9936 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
9937 types to which the references refer are the same type except for
9938 top-level cv-qualifiers, and the type to which the reference
9939 initialized by S2 refers is more cv-qualified than the type to
9940 which the reference initialized by S1 refers.
9942 DR 1328 [over.match.best]: the context is an initialization by
9943 conversion function for direct reference binding (13.3.1.6) of a
9944 reference to function type, the return type of F1 is the same kind of
9945 reference (i.e. lvalue or rvalue) as the reference being initialized,
9946 and the return type of F2 is not. */
9948 if (ref_conv1
&& ref_conv2
)
9950 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
9951 && (ref_conv1
->rvaluedness_matches_p
9952 != ref_conv2
->rvaluedness_matches_p
)
9953 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
9954 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
9955 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
9957 if (ref_conv1
->bad_p
9958 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
9959 TREE_TYPE (ref_conv2
->type
)))
9960 /* Don't prefer a bad conversion that drops cv-quals to a bad
9961 conversion with the wrong rvalueness. */
9963 return (ref_conv1
->rvaluedness_matches_p
9964 - ref_conv2
->rvaluedness_matches_p
);
9967 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
9969 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
9970 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
9971 if (ref_conv1
->bad_p
)
9973 /* Prefer the one that drops fewer cv-quals. */
9974 tree ftype
= next_conversion (ref_conv1
)->type
;
9975 int fquals
= cp_type_quals (ftype
);
9979 return comp_cv_qualification (q2
, q1
);
9983 /* Neither conversion sequence is better than the other. */
9987 /* The source type for this standard conversion sequence. */
9990 source_type (conversion
*t
)
9992 for (;; t
= next_conversion (t
))
9994 if (t
->kind
== ck_user
9995 || t
->kind
== ck_ambig
9996 || t
->kind
== ck_identity
)
10002 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10003 a pointer to LOSER and re-running joust to produce the warning if WINNER
10004 is actually used. */
10007 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10009 candidate_warning
*cw
= (candidate_warning
*)
10010 conversion_obstack_alloc (sizeof (candidate_warning
));
10012 cw
->next
= winner
->warnings
;
10013 winner
->warnings
= cw
;
10016 /* Compare two candidates for overloading as described in
10017 [over.match.best]. Return values:
10019 1: cand1 is better than cand2
10020 -1: cand2 is better than cand1
10021 0: cand1 and cand2 are indistinguishable */
10024 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10025 tsubst_flags_t complain
)
10028 int off1
= 0, off2
= 0;
10032 /* Candidates that involve bad conversions are always worse than those
10034 if (cand1
->viable
> cand2
->viable
)
10036 if (cand1
->viable
< cand2
->viable
)
10039 /* If we have two pseudo-candidates for conversions to the same type,
10040 or two candidates for the same function, arbitrarily pick one. */
10041 if (cand1
->fn
== cand2
->fn
10042 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10045 /* Prefer a non-deleted function over an implicitly deleted move
10046 constructor or assignment operator. This differs slightly from the
10047 wording for issue 1402 (which says the move op is ignored by overload
10048 resolution), but this way produces better error messages. */
10049 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10050 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10051 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10053 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10054 && move_fn_p (cand1
->fn
))
10056 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10057 && move_fn_p (cand2
->fn
))
10061 /* a viable function F1
10062 is defined to be a better function than another viable function F2 if
10063 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10064 ICSi(F2), and then */
10066 /* for some argument j, ICSj(F1) is a better conversion sequence than
10069 /* For comparing static and non-static member functions, we ignore
10070 the implicit object parameter of the non-static function. The
10071 standard says to pretend that the static function has an object
10072 parm, but that won't work with operator overloading. */
10073 len
= cand1
->num_convs
;
10074 if (len
!= cand2
->num_convs
)
10076 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10077 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10079 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10080 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10081 /* We're comparing a near-match list constructor and a near-match
10082 non-list constructor. Just treat them as unordered. */
10085 gcc_assert (static_1
!= static_2
);
10096 for (i
= 0; i
< len
; ++i
)
10098 conversion
*t1
= cand1
->convs
[i
+ off1
];
10099 conversion
*t2
= cand2
->convs
[i
+ off2
];
10100 int comp
= compare_ics (t1
, t2
);
10104 if ((complain
& tf_warning
)
10106 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10107 == cr_std
+ cr_promotion
)
10108 && t1
->kind
== ck_std
10109 && t2
->kind
== ck_std
10110 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10111 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10112 && (TYPE_PRECISION (t1
->type
)
10113 == TYPE_PRECISION (t2
->type
))
10114 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10115 || (TREE_CODE (next_conversion (t1
)->type
)
10116 == ENUMERAL_TYPE
)))
10118 tree type
= next_conversion (t1
)->type
;
10120 struct z_candidate
*w
, *l
;
10122 type1
= t1
->type
, type2
= t2
->type
,
10123 w
= cand1
, l
= cand2
;
10125 type1
= t2
->type
, type2
= t1
->type
,
10126 w
= cand2
, l
= cand1
;
10130 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10131 type
, type1
, type2
);
10132 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10135 add_warning (w
, l
);
10138 if (winner
&& comp
!= winner
)
10147 /* warn about confusing overload resolution for user-defined conversions,
10148 either between a constructor and a conversion op, or between two
10150 if ((complain
& tf_warning
)
10151 && winner
&& warn_conversion
&& cand1
->second_conv
10152 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10153 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10155 struct z_candidate
*w
, *l
;
10156 bool give_warning
= false;
10159 w
= cand1
, l
= cand2
;
10161 w
= cand2
, l
= cand1
;
10163 /* We don't want to complain about `X::operator T1 ()'
10164 beating `X::operator T2 () const', when T2 is a no less
10165 cv-qualified version of T1. */
10166 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10167 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10169 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10170 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10172 if (TREE_CODE (t
) == TREE_CODE (f
) && POINTER_TYPE_P (t
))
10177 if (!comp_ptr_ttypes (t
, f
))
10178 give_warning
= true;
10181 give_warning
= true;
10187 tree source
= source_type (w
->convs
[0]);
10188 if (POINTER_TYPE_P (source
))
10189 source
= TREE_TYPE (source
);
10190 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10191 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10192 source
, w
->second_conv
->type
))
10194 inform (input_location
, " because conversion sequence for the argument is better");
10198 add_warning (w
, l
);
10204 /* DR 495 moved this tiebreaker above the template ones. */
10205 /* or, if not that,
10206 the context is an initialization by user-defined conversion (see
10207 _dcl.init_ and _over.match.user_) and the standard conversion
10208 sequence from the return type of F1 to the destination type (i.e.,
10209 the type of the entity being initialized) is a better conversion
10210 sequence than the standard conversion sequence from the return type
10211 of F2 to the destination type. */
10213 if (cand1
->second_conv
)
10215 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10220 /* or, if not that,
10221 F1 is a non-template function and F2 is a template function
10224 if (!cand1
->template_decl
&& cand2
->template_decl
)
10226 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10229 /* or, if not that,
10230 F1 and F2 are template functions and the function template for F1 is
10231 more specialized than the template for F2 according to the partial
10234 if (cand1
->template_decl
&& cand2
->template_decl
)
10236 winner
= more_specialized_fn
10237 (TI_TEMPLATE (cand1
->template_decl
),
10238 TI_TEMPLATE (cand2
->template_decl
),
10239 /* [temp.func.order]: The presence of unused ellipsis and default
10240 arguments has no effect on the partial ordering of function
10241 templates. add_function_candidate() will not have
10242 counted the "this" argument for constructors. */
10243 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10249 // or, if not that, F1 is more constrained than F2.
10250 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10252 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10257 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10258 if (deduction_guide_p (cand1
->fn
))
10260 gcc_assert (deduction_guide_p (cand2
->fn
));
10261 /* We distinguish between candidates from an explicit deduction guide and
10262 candidates built from a constructor based on DECL_ARTIFICIAL. */
10263 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10264 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10266 return art2
- art1
;
10270 /* Prefer the special copy guide over a declared copy/move
10272 if (copy_guide_p (cand1
->fn
))
10274 if (copy_guide_p (cand2
->fn
))
10277 /* Prefer a candidate generated from a non-template constructor. */
10278 int tg1
= template_guide_p (cand1
->fn
);
10279 int tg2
= template_guide_p (cand2
->fn
);
10285 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10286 for all arguments the corresponding parameters of F1 and F2 have the same
10287 type (CWG 2273/2277). */
10288 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10289 && !DECL_CONV_FN_P (cand1
->fn
)
10290 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10291 && !DECL_CONV_FN_P (cand2
->fn
))
10293 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10294 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10296 bool used1
= false;
10297 bool used2
= false;
10298 if (base1
== base2
)
10299 /* No difference. */;
10300 else if (DERIVED_FROM_P (base1
, base2
))
10302 else if (DERIVED_FROM_P (base2
, base1
))
10305 if (int diff
= used2
- used1
)
10307 for (i
= 0; i
< len
; ++i
)
10309 conversion
*t1
= cand1
->convs
[i
+ off1
];
10310 conversion
*t2
= cand2
->convs
[i
+ off2
];
10311 if (!same_type_p (t1
->type
, t2
->type
))
10319 /* Check whether we can discard a builtin candidate, either because we
10320 have two identical ones or matching builtin and non-builtin candidates.
10322 (Pedantically in the latter case the builtin which matched the user
10323 function should not be added to the overload set, but we spot it here.
10326 ... the builtin candidates include ...
10327 - do not have the same parameter type list as any non-template
10328 non-member candidate. */
10330 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10332 for (i
= 0; i
< len
; ++i
)
10333 if (!same_type_p (cand1
->convs
[i
]->type
,
10334 cand2
->convs
[i
]->type
))
10336 if (i
== cand1
->num_convs
)
10338 if (cand1
->fn
== cand2
->fn
)
10339 /* Two built-in candidates; arbitrarily pick one. */
10341 else if (identifier_p (cand1
->fn
))
10342 /* cand1 is built-in; prefer cand2. */
10345 /* cand2 is built-in; prefer cand1. */
10350 /* For candidates of a multi-versioned function, make the version with
10351 the highest priority win. This version will be checked for dispatching
10352 first. If this version can be inlined into the caller, the front-end
10353 will simply make a direct call to this function. */
10355 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10356 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10357 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10358 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10360 tree f1
= TREE_TYPE (cand1
->fn
);
10361 tree f2
= TREE_TYPE (cand2
->fn
);
10362 tree p1
= TYPE_ARG_TYPES (f1
);
10363 tree p2
= TYPE_ARG_TYPES (f2
);
10365 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10366 is possible that cand1->fn and cand2->fn are function versions but of
10367 different functions. Check types to see if they are versions of the same
10369 if (compparms (p1
, p2
)
10370 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10372 /* Always make the version with the higher priority, more
10373 specialized, win. */
10374 gcc_assert (targetm
.compare_version_priority
);
10375 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10382 /* If the two function declarations represent the same function (this can
10383 happen with declarations in multiple scopes and arg-dependent lookup),
10384 arbitrarily choose one. But first make sure the default args we're
10386 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10387 && equal_functions (cand1
->fn
, cand2
->fn
))
10389 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10390 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10392 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10394 for (i
= 0; i
< len
; ++i
)
10396 /* Don't crash if the fn is variadic. */
10399 parms1
= TREE_CHAIN (parms1
);
10400 parms2
= TREE_CHAIN (parms2
);
10404 parms1
= TREE_CHAIN (parms1
);
10406 parms2
= TREE_CHAIN (parms2
);
10408 for (; parms1
; ++i
)
10410 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10411 TREE_PURPOSE (parms2
)))
10415 if (complain
& tf_error
)
10417 if (permerror (input_location
,
10418 "default argument mismatch in "
10419 "overload resolution"))
10421 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10422 " candidate 1: %q#F", cand1
->fn
);
10423 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10424 " candidate 2: %q#F", cand2
->fn
);
10431 add_warning (cand1
, cand2
);
10434 parms1
= TREE_CHAIN (parms1
);
10435 parms2
= TREE_CHAIN (parms2
);
10443 /* Extension: If the worst conversion for one candidate is worse than the
10444 worst conversion for the other, take the first. */
10445 if (!pedantic
&& (complain
& tf_warning_or_error
))
10447 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
10448 struct z_candidate
*w
= 0, *l
= 0;
10450 for (i
= 0; i
< len
; ++i
)
10452 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
10453 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
10454 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
10455 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
10458 winner
= 1, w
= cand1
, l
= cand2
;
10460 winner
= -1, w
= cand2
, l
= cand1
;
10463 /* Don't choose a deleted function over ambiguity. */
10464 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
10468 pedwarn (input_location
, 0,
10469 "ISO C++ says that these are ambiguous, even "
10470 "though the worst conversion for the first is better than "
10471 "the worst conversion for the second:");
10472 print_z_candidate (input_location
, _("candidate 1:"), w
);
10473 print_z_candidate (input_location
, _("candidate 2:"), l
);
10476 add_warning (w
, l
);
10481 gcc_assert (!winner
);
10485 /* Given a list of candidates for overloading, find the best one, if any.
10486 This algorithm has a worst case of O(2n) (winner is last), and a best
10487 case of O(n/2) (totally ambiguous); much better than a sorting
10490 static struct z_candidate
*
10491 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
10493 struct z_candidate
*champ
= candidates
, *challenger
;
10495 int champ_compared_to_predecessor
= 0;
10497 /* Walk through the list once, comparing each current champ to the next
10498 candidate, knocking out a candidate or two with each comparison. */
10500 for (challenger
= champ
->next
; challenger
; )
10502 fate
= joust (champ
, challenger
, 0, complain
);
10504 challenger
= challenger
->next
;
10509 champ
= challenger
->next
;
10512 champ_compared_to_predecessor
= 0;
10516 champ
= challenger
;
10517 champ_compared_to_predecessor
= 1;
10520 challenger
= champ
->next
;
10524 /* Make sure the champ is better than all the candidates it hasn't yet
10525 been compared to. */
10527 for (challenger
= candidates
;
10528 challenger
!= champ
10529 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
10530 challenger
= challenger
->next
)
10532 fate
= joust (champ
, challenger
, 0, complain
);
10540 /* Returns nonzero if things of type FROM can be converted to TO. */
10543 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
10545 tree arg
= NULL_TREE
;
10546 /* implicit_conversion only considers user-defined conversions
10547 if it has an expression for the call argument list. */
10548 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
10549 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
10550 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
10553 /* Returns nonzero if things of type FROM can be converted to TO with a
10554 standard conversion. */
10557 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
10559 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
10562 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
10565 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
10566 tsubst_flags_t complain
)
10572 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10573 p
= conversion_obstack_alloc (0);
10574 /* We want to discard any access checks done for this test,
10575 as we might not be in the appropriate access context and
10576 we'll do the check again when we actually perform the
10578 push_deferring_access_checks (dk_deferred
);
10580 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10582 ok_p
= (t
&& !t
->bad_p
);
10584 /* Discard the access checks now. */
10585 pop_deferring_access_checks ();
10586 /* Free all the conversions we allocated. */
10587 obstack_free (&conversion_obstack
, p
);
10592 /* Like can_convert_arg, but allows dubious conversions as well. */
10595 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
10596 tsubst_flags_t complain
)
10601 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10602 p
= conversion_obstack_alloc (0);
10603 /* Try to perform the conversion. */
10604 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10606 /* Free all the conversions we allocated. */
10607 obstack_free (&conversion_obstack
, p
);
10612 /* Convert EXPR to TYPE. Return the converted expression.
10614 Note that we allow bad conversions here because by the time we get to
10615 this point we are committed to doing the conversion. If we end up
10616 doing a bad conversion, convert_like will complain. */
10619 perform_implicit_conversion_flags (tree type
, tree expr
,
10620 tsubst_flags_t complain
, int flags
)
10624 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
10626 if (TREE_CODE (type
) == REFERENCE_TYPE
)
10627 expr
= mark_lvalue_use (expr
);
10629 expr
= mark_rvalue_use (expr
);
10631 if (error_operand_p (expr
))
10632 return error_mark_node
;
10634 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10635 p
= conversion_obstack_alloc (0);
10637 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
10638 /*c_cast_p=*/false,
10643 if (complain
& tf_error
)
10645 /* If expr has unknown type, then it is an overloaded function.
10646 Call instantiate_type to get good error messages. */
10647 if (TREE_TYPE (expr
) == unknown_type_node
)
10648 instantiate_type (type
, expr
, complain
);
10649 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
10650 /* We gave an error. */;
10652 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
10653 TREE_TYPE (expr
), type
);
10655 expr
= error_mark_node
;
10657 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
10659 /* In a template, we are only concerned about determining the
10660 type of non-dependent expressions, so we do not have to
10661 perform the actual conversion. But for initializers, we
10662 need to be able to perform it at instantiation
10663 (or instantiate_non_dependent_expr) time. */
10664 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
10665 if (!(flags
& LOOKUP_ONLYCONVERTING
))
10666 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
10669 expr
= convert_like (conv
, expr
, complain
);
10671 /* Free all the conversions we allocated. */
10672 obstack_free (&conversion_obstack
, p
);
10678 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
10680 return perform_implicit_conversion_flags (type
, expr
, complain
,
10684 /* Convert EXPR to TYPE (as a direct-initialization) if that is
10685 permitted. If the conversion is valid, the converted expression is
10686 returned. Otherwise, NULL_TREE is returned, except in the case
10687 that TYPE is a class type; in that case, an error is issued. If
10688 C_CAST_P is true, then this direct-initialization is taking
10689 place as part of a static_cast being attempted as part of a C-style
10693 perform_direct_initialization_if_possible (tree type
,
10696 tsubst_flags_t complain
)
10701 if (type
== error_mark_node
|| error_operand_p (expr
))
10702 return error_mark_node
;
10705 If the destination type is a (possibly cv-qualified) class type:
10707 -- If the initialization is direct-initialization ...,
10708 constructors are considered. ... If no constructor applies, or
10709 the overload resolution is ambiguous, the initialization is
10711 if (CLASS_TYPE_P (type
))
10713 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
10714 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
10715 &args
, type
, LOOKUP_NORMAL
, complain
);
10716 release_tree_vector (args
);
10717 return build_cplus_new (type
, expr
, complain
);
10720 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10721 p
= conversion_obstack_alloc (0);
10723 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
10725 LOOKUP_NORMAL
, complain
);
10726 if (!conv
|| conv
->bad_p
)
10728 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
10730 /* In a template, we are only concerned about determining the
10731 type of non-dependent expressions, so we do not have to
10732 perform the actual conversion. But for initializers, we
10733 need to be able to perform it at instantiation
10734 (or instantiate_non_dependent_expr) time. */
10735 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
10736 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
10739 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
10740 /*issue_conversion_warnings=*/false,
10744 /* Free all the conversions we allocated. */
10745 obstack_free (&conversion_obstack
, p
);
10750 /* When initializing a reference that lasts longer than a full-expression,
10751 this special rule applies:
10755 The temporary to which the reference is bound or the temporary
10756 that is the complete object to which the reference is bound
10757 persists for the lifetime of the reference.
10759 The temporaries created during the evaluation of the expression
10760 initializing the reference, except the temporary to which the
10761 reference is bound, are destroyed at the end of the
10762 full-expression in which they are created.
10764 In that case, we store the converted expression into a new
10765 VAR_DECL in a new scope.
10767 However, we want to be careful not to create temporaries when
10768 they are not required. For example, given:
10771 struct D : public B {};
10775 there is no need to copy the return value from "f"; we can just
10776 extend its lifetime. Similarly, given:
10779 struct T { operator S(); };
10783 we can extend the lifetime of the return value of the conversion
10786 The next several functions are involved in this lifetime extension. */
10788 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
10789 reference is being bound to a temporary. Create and return a new
10790 VAR_DECL with the indicated TYPE; this variable will store the value to
10791 which the reference is bound. */
10794 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
10796 tree var
= create_temporary_var (type
);
10798 /* Register the variable. */
10800 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
10802 /* Namespace-scope or local static; give it a mangled name. */
10803 /* FIXME share comdat with decl? */
10805 TREE_STATIC (var
) = TREE_STATIC (decl
);
10806 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
10807 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
10809 tree name
= mangle_ref_init_variable (decl
);
10810 DECL_NAME (var
) = name
;
10811 SET_DECL_ASSEMBLER_NAME (var
, name
);
10813 var
= pushdecl (var
);
10816 /* Create a new cleanup level if necessary. */
10817 maybe_push_cleanup_level (type
);
10822 /* EXPR is the initializer for a variable DECL of reference or
10823 std::initializer_list type. Create, push and return a new VAR_DECL
10824 for the initializer so that it will live as long as DECL. Any
10825 cleanup for the new variable is returned through CLEANUP, and the
10826 code to initialize the new variable is returned through INITP. */
10829 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
10836 /* Create the temporary variable. */
10837 type
= TREE_TYPE (expr
);
10838 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
10839 layout_decl (var
, 0);
10840 /* If the rvalue is the result of a function call it will be
10841 a TARGET_EXPR. If it is some other construct (such as a
10842 member access expression where the underlying object is
10843 itself the result of a function call), turn it into a
10844 TARGET_EXPR here. It is important that EXPR be a
10845 TARGET_EXPR below since otherwise the INIT_EXPR will
10846 attempt to make a bitwise copy of EXPR to initialize
10848 if (TREE_CODE (expr
) != TARGET_EXPR
)
10849 expr
= get_target_expr (expr
);
10851 if (TREE_CODE (decl
) == FIELD_DECL
10852 && extra_warnings
&& !TREE_NO_WARNING (decl
))
10854 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
10855 "until the constructor exits", decl
);
10856 TREE_NO_WARNING (decl
) = true;
10859 /* Recursively extend temps in this initializer. */
10860 TARGET_EXPR_INITIAL (expr
)
10861 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
10863 /* Any reference temp has a non-trivial initializer. */
10864 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
10866 /* If the initializer is constant, put it in DECL_INITIAL so we get
10867 static initialization and use in constant expressions. */
10868 init
= maybe_constant_init (expr
);
10869 if (TREE_CONSTANT (init
))
10871 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
10873 /* 5.19 says that a constant expression can include an
10874 lvalue-rvalue conversion applied to "a glvalue of literal type
10875 that refers to a non-volatile temporary object initialized
10876 with a constant expression". Rather than try to communicate
10877 that this VAR_DECL is a temporary, just mark it constexpr.
10879 Currently this is only useful for initializer_list temporaries,
10880 since reference vars can't appear in constant expressions. */
10881 DECL_DECLARED_CONSTEXPR_P (var
) = true;
10882 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
10883 TREE_CONSTANT (var
) = true;
10885 DECL_INITIAL (var
) = init
;
10889 /* Create the INIT_EXPR that will initialize the temporary
10891 init
= split_nonconstant_init (var
, expr
);
10892 if (at_function_scope_p ())
10894 add_decl_expr (var
);
10896 if (TREE_STATIC (var
))
10897 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
10900 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
10902 vec_safe_push (*cleanups
, cleanup
);
10905 /* We must be careful to destroy the temporary only
10906 after its initialization has taken place. If the
10907 initialization throws an exception, then the
10908 destructor should not be run. We cannot simply
10909 transform INIT into something like:
10911 (INIT, ({ CLEANUP_STMT; }))
10913 because emit_local_var always treats the
10914 initializer as a full-expression. Thus, the
10915 destructor would run too early; it would run at the
10916 end of initializing the reference variable, rather
10917 than at the end of the block enclosing the
10918 reference variable.
10920 The solution is to pass back a cleanup expression
10921 which the caller is responsible for attaching to
10922 the statement tree. */
10926 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
10927 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
10929 if (CP_DECL_THREAD_LOCAL_P (var
))
10930 tls_aggregates
= tree_cons (NULL_TREE
, var
,
10933 static_aggregates
= tree_cons (NULL_TREE
, var
,
10934 static_aggregates
);
10937 /* Check whether the dtor is callable. */
10938 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
10940 /* Avoid -Wunused-variable warning (c++/38958). */
10941 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
10943 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
10949 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
10950 initializing a variable of that TYPE. */
10953 initialize_reference (tree type
, tree expr
,
10954 int flags
, tsubst_flags_t complain
)
10958 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
10960 if (type
== error_mark_node
|| error_operand_p (expr
))
10961 return error_mark_node
;
10963 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10964 p
= conversion_obstack_alloc (0);
10966 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
10968 if (!conv
|| conv
->bad_p
)
10970 if (complain
& tf_error
)
10973 convert_like (conv
, expr
, complain
);
10974 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
10975 && !TYPE_REF_IS_RVALUE (type
)
10976 && !lvalue_p (expr
))
10977 error_at (loc
, "invalid initialization of non-const reference of "
10978 "type %qH from an rvalue of type %qI",
10979 type
, TREE_TYPE (expr
));
10981 error_at (loc
, "invalid initialization of reference of type "
10982 "%qH from expression of type %qI", type
,
10985 return error_mark_node
;
10988 if (conv
->kind
== ck_ref_bind
)
10989 /* Perform the conversion. */
10990 expr
= convert_like (conv
, expr
, complain
);
10991 else if (conv
->kind
== ck_ambig
)
10992 /* We gave an error in build_user_type_conversion_1. */
10993 expr
= error_mark_node
;
10995 gcc_unreachable ();
10997 /* Free all the conversions we allocated. */
10998 obstack_free (&conversion_obstack
, p
);
11003 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11004 which is bound either to a reference or a std::initializer_list. */
11007 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11012 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11014 TREE_OPERAND (sub
, 1)
11015 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11018 if (TREE_CODE (sub
) != ADDR_EXPR
)
11020 /* Deal with binding to a subobject. */
11021 for (p
= &TREE_OPERAND (sub
, 0); TREE_CODE (*p
) == COMPONENT_REF
; )
11022 p
= &TREE_OPERAND (*p
, 0);
11023 if (TREE_CODE (*p
) == TARGET_EXPR
)
11025 tree subinit
= NULL_TREE
;
11026 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11027 recompute_tree_invariant_for_addr_expr (sub
);
11029 init
= fold_convert (TREE_TYPE (init
), sub
);
11031 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11036 /* INIT is part of the initializer for DECL. If there are any
11037 reference or initializer lists being initialized, extend their
11038 lifetime to match that of DECL. */
11041 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11043 tree type
= TREE_TYPE (init
);
11044 if (processing_template_decl
)
11046 if (TREE_CODE (type
) == REFERENCE_TYPE
)
11047 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11051 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11052 ctor
= TARGET_EXPR_INITIAL (ctor
);
11053 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11055 if (is_std_init_list (type
))
11057 /* The temporary array underlying a std::initializer_list
11058 is handled like a reference temporary. */
11059 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11060 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11061 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11066 constructor_elt
*p
;
11067 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11068 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11069 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11071 recompute_constructor_flags (ctor
);
11072 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11073 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11080 /* Returns true iff an initializer for TYPE could contain temporaries that
11081 need to be extended because they are bound to references or
11082 std::initializer_list. */
11085 type_has_extended_temps (tree type
)
11087 type
= strip_array_types (type
);
11088 if (TREE_CODE (type
) == REFERENCE_TYPE
)
11090 if (CLASS_TYPE_P (type
))
11092 if (is_std_init_list (type
))
11094 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11095 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11096 if (type_has_extended_temps (TREE_TYPE (f
)))
11102 /* Returns true iff TYPE is some variant of std::initializer_list. */
11105 is_std_init_list (tree type
)
11107 if (!TYPE_P (type
))
11109 if (cxx_dialect
== cxx98
)
11111 /* Look through typedefs. */
11112 type
= TYPE_MAIN_VARIANT (type
);
11113 return (CLASS_TYPE_P (type
)
11114 && CP_TYPE_CONTEXT (type
) == std_node
11115 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11118 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11119 will accept an argument list of a single std::initializer_list<T>. */
11122 is_list_ctor (tree decl
)
11124 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11127 if (!args
|| args
== void_list_node
)
11130 arg
= non_reference (TREE_VALUE (args
));
11131 if (!is_std_init_list (arg
))
11134 args
= TREE_CHAIN (args
);
11136 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11137 /* There are more non-defaulted parms. */
11143 #include "gt-cp-call.h"