1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987-2015 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 "stor-layout.h"
32 #include "trans-mem.h"
33 #include "stringpool.h"
37 #include "diagnostic-core.h"
41 #include "langhooks.h"
42 #include "c-family/c-objc.h"
44 #include "hard-reg-set.h"
47 #include "internal-fn.h"
49 /* The various kinds of conversion. */
51 enum conversion_kind
{
67 /* The rank of the conversion. Order of the enumerals matters; better
68 conversions should come earlier in the list. */
70 enum conversion_rank
{
81 /* An implicit conversion sequence, in the sense of [over.best.ics].
82 The first conversion to be performed is at the end of the chain.
83 That conversion is always a cr_identity conversion. */
86 /* The kind of conversion represented by this step. */
88 /* The rank of this conversion. */
90 BOOL_BITFIELD user_conv_p
: 1;
91 BOOL_BITFIELD ellipsis_p
: 1;
92 BOOL_BITFIELD this_p
: 1;
93 /* True if this conversion would be permitted with a bending of
94 language standards, e.g. disregarding pointer qualifiers or
95 converting integers to pointers. */
96 BOOL_BITFIELD bad_p
: 1;
97 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
98 temporary should be created to hold the result of the
100 BOOL_BITFIELD need_temporary_p
: 1;
101 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
102 from a pointer-to-derived to pointer-to-base is being performed. */
103 BOOL_BITFIELD base_p
: 1;
104 /* If KIND is ck_ref_bind, true when either an lvalue reference is
105 being bound to an lvalue expression or an rvalue reference is
106 being bound to an rvalue expression. If KIND is ck_rvalue,
107 true when we should treat an lvalue as an rvalue (12.8p33). If
108 KIND is ck_base, always false. */
109 BOOL_BITFIELD rvaluedness_matches_p
: 1;
110 BOOL_BITFIELD check_narrowing
: 1;
111 /* The type of the expression resulting from the conversion. */
114 /* The next conversion in the chain. Since the conversions are
115 arranged from outermost to innermost, the NEXT conversion will
116 actually be performed before this conversion. This variant is
117 used only when KIND is neither ck_identity, ck_ambig nor
118 ck_list. Please use the next_conversion function instead
119 of using this field directly. */
121 /* The expression at the beginning of the conversion chain. This
122 variant is used only if KIND is ck_identity or ck_ambig. */
124 /* The array of conversions for an initializer_list, so this
125 variant is used only when KIN D is ck_list. */
128 /* The function candidate corresponding to this conversion
129 sequence. This field is only used if KIND is ck_user. */
130 struct z_candidate
*cand
;
133 #define CONVERSION_RANK(NODE) \
134 ((NODE)->bad_p ? cr_bad \
135 : (NODE)->ellipsis_p ? cr_ellipsis \
136 : (NODE)->user_conv_p ? cr_user \
139 #define BAD_CONVERSION_RANK(NODE) \
140 ((NODE)->ellipsis_p ? cr_ellipsis \
141 : (NODE)->user_conv_p ? cr_user \
144 static struct obstack conversion_obstack
;
145 static bool conversion_obstack_initialized
;
146 struct rejection_reason
;
148 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
149 static int equal_functions (tree
, tree
);
150 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
152 static int compare_ics (conversion
*, conversion
*);
153 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
154 static tree
build_java_interface_fn_ref (tree
, tree
);
155 #define convert_like(CONV, EXPR, COMPLAIN) \
156 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 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), 0, \
161 /*issue_conversion_warnings=*/true, \
162 /*c_cast_p=*/false, (COMPLAIN))
163 static tree
convert_like_real (conversion
*, tree
, tree
, int, 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 struct z_candidate
*add_template_conv_candidate
181 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
182 tree
, tree
, tree
, tsubst_flags_t
);
183 static void add_builtin_candidates
184 (struct z_candidate
**, enum tree_code
, enum tree_code
,
185 tree
, tree
*, int, tsubst_flags_t
);
186 static void add_builtin_candidate
187 (struct z_candidate
**, enum tree_code
, enum tree_code
,
188 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
189 static bool is_complete (tree
);
190 static void build_builtin_candidate
191 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
192 int, tsubst_flags_t
);
193 static struct z_candidate
*add_conv_candidate
194 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
195 tree
, tsubst_flags_t
);
196 static struct z_candidate
*add_function_candidate
197 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
198 tree
, int, tsubst_flags_t
);
199 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
201 static conversion
*standard_conversion (tree
, tree
, tree
, bool, int);
202 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
204 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
205 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
206 static conversion
*next_conversion (conversion
*);
207 static bool is_subseq (conversion
*, conversion
*);
208 static conversion
*maybe_handle_ref_bind (conversion
**);
209 static void maybe_handle_implicit_object (conversion
**);
210 static struct z_candidate
*add_candidate
211 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
212 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
213 static tree
source_type (conversion
*);
214 static void add_warning (struct z_candidate
*, struct z_candidate
*);
215 static bool reference_compatible_p (tree
, tree
);
216 static conversion
*direct_reference_binding (tree
, conversion
*);
217 static bool promoted_arithmetic_type_p (tree
);
218 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
219 static char *name_as_c_string (tree
, tree
, bool *);
220 static tree
prep_operand (tree
);
221 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
222 bool, tree
, tree
, int, struct z_candidate
**,
224 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
225 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
227 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
228 NAME can take many forms... */
231 check_dtor_name (tree basetype
, tree name
)
233 /* Just accept something we've already complained about. */
234 if (name
== error_mark_node
)
237 if (TREE_CODE (name
) == TYPE_DECL
)
238 name
= TREE_TYPE (name
);
239 else if (TYPE_P (name
))
241 else if (identifier_p (name
))
243 if ((MAYBE_CLASS_TYPE_P (basetype
)
244 && name
== constructor_name (basetype
))
245 || (TREE_CODE (basetype
) == ENUMERAL_TYPE
246 && name
== TYPE_IDENTIFIER (basetype
)))
249 name
= get_type_value (name
);
255 template <class T> struct S { ~S(); };
259 NAME will be a class template. */
260 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
264 if (!name
|| name
== error_mark_node
)
266 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
269 /* We want the address of a function or method. We avoid creating a
270 pointer-to-member function. */
273 build_addr_func (tree function
, tsubst_flags_t complain
)
275 tree type
= TREE_TYPE (function
);
277 /* We have to do these by hand to avoid real pointer to member
279 if (TREE_CODE (type
) == METHOD_TYPE
)
281 if (TREE_CODE (function
) == OFFSET_REF
)
283 tree object
= build_address (TREE_OPERAND (function
, 0));
284 return get_member_function_from_ptrfunc (&object
,
285 TREE_OPERAND (function
, 1),
288 function
= build_address (function
);
291 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
296 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
297 POINTER_TYPE to those. Note, pointer to member function types
298 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
299 two variants. build_call_a is the primitive taking an array of
300 arguments, while build_call_n is a wrapper that handles varargs. */
303 build_call_n (tree function
, int n
, ...)
306 return build_call_a (function
, 0, NULL
);
309 tree
*argarray
= XALLOCAVEC (tree
, n
);
314 for (i
= 0; i
< n
; i
++)
315 argarray
[i
] = va_arg (ap
, tree
);
317 return build_call_a (function
, n
, argarray
);
321 /* Update various flags in cfun and the call itself based on what is being
322 called. Split out of build_call_a so that bot_manip can use it too. */
325 set_flags_from_callee (tree call
)
328 tree decl
= get_callee_fndecl (call
);
330 /* We check both the decl and the type; a function may be known not to
331 throw without being declared throw(). */
332 nothrow
= decl
&& TREE_NOTHROW (decl
);
333 if (CALL_EXPR_FN (call
))
334 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call
))));
335 else if (internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
338 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
339 cp_function_chain
->can_throw
= 1;
341 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
342 current_function_returns_abnormally
= 1;
344 TREE_NOTHROW (call
) = nothrow
;
348 build_call_a (tree function
, int n
, tree
*argarray
)
355 function
= build_addr_func (function
, tf_warning_or_error
);
357 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
358 fntype
= TREE_TYPE (TREE_TYPE (function
));
359 gcc_assert (TREE_CODE (fntype
) == FUNCTION_TYPE
360 || TREE_CODE (fntype
) == METHOD_TYPE
);
361 result_type
= TREE_TYPE (fntype
);
362 /* An rvalue has no cv-qualifiers. */
363 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
364 result_type
= cv_unqualified (result_type
);
366 function
= build_call_array_loc (input_location
,
367 result_type
, function
, n
, argarray
);
368 set_flags_from_callee (function
);
370 decl
= get_callee_fndecl (function
);
372 if (decl
&& !TREE_USED (decl
))
374 /* We invoke build_call directly for several library
375 functions. These may have been declared normally if
376 we're building libgcc, so we can't just check
378 gcc_assert (DECL_ARTIFICIAL (decl
)
379 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
384 require_complete_eh_spec_types (fntype
, decl
);
386 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
388 /* Don't pass empty class objects by value. This is useful
389 for tags in STL, which are used to control overload resolution.
390 We don't need to handle other cases of copying empty classes. */
391 if (! decl
|| ! DECL_BUILT_IN (decl
))
392 for (i
= 0; i
< n
; i
++)
394 tree arg
= CALL_EXPR_ARG (function
, i
);
395 if (is_empty_class (TREE_TYPE (arg
))
396 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
398 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
399 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
400 CALL_EXPR_ARG (function
, i
) = arg
;
407 /* New overloading code. */
411 struct candidate_warning
{
413 candidate_warning
*next
;
416 /* Information for providing diagnostics about why overloading failed. */
418 enum rejection_reason_code
{
421 rr_explicit_conversion
,
422 rr_template_conversion
,
424 rr_bad_arg_conversion
,
425 rr_template_unification
,
427 rr_constraint_failure
430 struct conversion_info
{
431 /* The index of the argument, 0-based. */
433 /* The actual argument or its type. */
435 /* The type of the parameter. */
439 struct rejection_reason
{
440 enum rejection_reason_code code
;
442 /* Information about an arity mismatch. */
444 /* The expected number of arguments. */
446 /* The actual number of arguments in the call. */
448 /* Whether the call was a varargs call. */
451 /* Information about an argument conversion mismatch. */
452 struct conversion_info conversion
;
453 /* Same, but for bad argument conversions. */
454 struct conversion_info bad_conversion
;
455 /* Information about template unification failures. These are the
456 parameters passed to fn_type_unification. */
464 unification_kind_t strict
;
466 } template_unification
;
467 /* Information about template instantiation failures. These are the
468 parameters passed to instantiate_template. */
472 } template_instantiation
;
477 /* The FUNCTION_DECL that will be called if this candidate is
478 selected by overload resolution. */
480 /* If not NULL_TREE, the first argument to use when calling this
483 /* The rest of the arguments to use when calling this function. If
484 there are no further arguments this may be NULL or it may be an
486 const vec
<tree
, va_gc
> *args
;
487 /* The implicit conversion sequences for each of the arguments to
490 /* The number of implicit conversion sequences. */
492 /* If FN is a user-defined conversion, the standard conversion
493 sequence from the type returned by FN to the desired destination
495 conversion
*second_conv
;
496 struct rejection_reason
*reason
;
497 /* If FN is a member function, the binfo indicating the path used to
498 qualify the name of FN at the call site. This path is used to
499 determine whether or not FN is accessible if it is selected by
500 overload resolution. The DECL_CONTEXT of FN will always be a
501 (possibly improper) base of this binfo. */
503 /* If FN is a non-static member function, the binfo indicating the
504 subobject to which the `this' pointer should be converted if FN
505 is selected by overload resolution. The type pointed to by
506 the `this' pointer must correspond to the most derived class
507 indicated by the CONVERSION_PATH. */
508 tree conversion_path
;
511 candidate_warning
*warnings
;
515 /* The flags active in add_candidate. */
519 /* Returns true iff T is a null pointer constant in the sense of
523 null_ptr_cst_p (tree t
)
525 tree type
= TREE_TYPE (t
);
529 A null pointer constant is an integral constant expression
530 (_expr.const_) rvalue of integer type that evaluates to zero or
531 an rvalue of type std::nullptr_t. */
532 if (NULLPTR_TYPE_P (type
))
535 if (cxx_dialect
>= cxx11
)
537 /* Core issue 903 says only literal 0 is a null pointer constant. */
538 if (TREE_CODE (type
) == INTEGER_TYPE
539 && TREE_CODE (t
) == INTEGER_CST
541 && !TREE_OVERFLOW (t
))
544 else if (CP_INTEGRAL_TYPE_P (type
))
546 t
= fold_non_dependent_expr (t
);
548 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
555 /* Returns true iff T is a null member pointer value (4.11). */
558 null_member_pointer_value_p (tree t
)
560 tree type
= TREE_TYPE (t
);
563 else if (TYPE_PTRMEMFUNC_P (type
))
564 return (TREE_CODE (t
) == CONSTRUCTOR
565 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
566 else if (TYPE_PTRDATAMEM_P (type
))
567 return integer_all_onesp (t
);
572 /* Returns nonzero if PARMLIST consists of only default parms,
573 ellipsis, and/or undeduced parameter packs. */
576 sufficient_parms_p (const_tree parmlist
)
578 for (; parmlist
&& parmlist
!= void_list_node
;
579 parmlist
= TREE_CHAIN (parmlist
))
580 if (!TREE_PURPOSE (parmlist
)
581 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
586 /* Allocate N bytes of memory from the conversion obstack. The memory
587 is zeroed before being returned. */
590 conversion_obstack_alloc (size_t n
)
593 if (!conversion_obstack_initialized
)
595 gcc_obstack_init (&conversion_obstack
);
596 conversion_obstack_initialized
= true;
598 p
= obstack_alloc (&conversion_obstack
, n
);
603 /* Allocate rejection reasons. */
605 static struct rejection_reason
*
606 alloc_rejection (enum rejection_reason_code code
)
608 struct rejection_reason
*p
;
609 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
614 static struct rejection_reason
*
615 arity_rejection (tree first_arg
, int expected
, int actual
)
617 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
618 int adjust
= first_arg
!= NULL_TREE
;
619 r
->u
.arity
.expected
= expected
- adjust
;
620 r
->u
.arity
.actual
= actual
- adjust
;
624 static struct rejection_reason
*
625 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
)
627 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
628 int adjust
= first_arg
!= NULL_TREE
;
629 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
630 r
->u
.conversion
.from
= from
;
631 r
->u
.conversion
.to_type
= to
;
635 static struct rejection_reason
*
636 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
)
638 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
639 int adjust
= first_arg
!= NULL_TREE
;
640 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
641 r
->u
.bad_conversion
.from
= from
;
642 r
->u
.bad_conversion
.to_type
= to
;
646 static struct rejection_reason
*
647 explicit_conversion_rejection (tree from
, tree to
)
649 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
650 r
->u
.conversion
.n_arg
= 0;
651 r
->u
.conversion
.from
= from
;
652 r
->u
.conversion
.to_type
= to
;
656 static struct rejection_reason
*
657 template_conversion_rejection (tree from
, tree to
)
659 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
660 r
->u
.conversion
.n_arg
= 0;
661 r
->u
.conversion
.from
= from
;
662 r
->u
.conversion
.to_type
= to
;
666 static struct rejection_reason
*
667 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
668 const tree
*args
, unsigned int nargs
,
669 tree return_type
, unification_kind_t strict
,
672 size_t args_n_bytes
= sizeof (*args
) * nargs
;
673 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
674 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
675 r
->u
.template_unification
.tmpl
= tmpl
;
676 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
677 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
678 /* Copy args to our own storage. */
679 memcpy (args1
, args
, args_n_bytes
);
680 r
->u
.template_unification
.args
= args1
;
681 r
->u
.template_unification
.nargs
= nargs
;
682 r
->u
.template_unification
.return_type
= return_type
;
683 r
->u
.template_unification
.strict
= strict
;
684 r
->u
.template_unification
.flags
= flags
;
688 static struct rejection_reason
*
689 template_unification_error_rejection (void)
691 return alloc_rejection (rr_template_unification
);
694 static struct rejection_reason
*
695 invalid_copy_with_fn_template_rejection (void)
697 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
701 // Build a constraint failure record, saving information into the
702 // template_instantiation field of the rejection. If FN is not a template
703 // declaration, the TMPL member is the FN declaration and TARGS is empty.
705 static struct rejection_reason
*
706 constraint_failure (tree fn
)
708 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
709 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
711 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
712 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
716 r
->u
.template_instantiation
.tmpl
= fn
;
717 r
->u
.template_instantiation
.targs
= NULL_TREE
;
722 /* Dynamically allocate a conversion. */
725 alloc_conversion (conversion_kind kind
)
728 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
733 #ifdef ENABLE_CHECKING
735 /* Make sure that all memory on the conversion obstack has been
739 validate_conversion_obstack (void)
741 if (conversion_obstack_initialized
)
742 gcc_assert ((obstack_next_free (&conversion_obstack
)
743 == obstack_base (&conversion_obstack
)));
746 #endif /* ENABLE_CHECKING */
748 /* Dynamically allocate an array of N conversions. */
751 alloc_conversions (size_t n
)
753 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
757 build_conv (conversion_kind code
, tree type
, conversion
*from
)
760 conversion_rank rank
= CONVERSION_RANK (from
);
762 /* Note that the caller is responsible for filling in t->cand for
763 user-defined conversions. */
764 t
= alloc_conversion (code
);
787 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
788 t
->bad_p
= from
->bad_p
;
793 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
794 specialization of std::initializer_list<T>, if such a conversion is
798 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
800 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
801 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
802 conversion
**subconvs
= alloc_conversions (len
);
807 /* Within a list-initialization we can have more user-defined
809 flags
&= ~LOOKUP_NO_CONVERSION
;
810 /* But no narrowing conversions. */
811 flags
|= LOOKUP_NO_NARROWING
;
813 /* Can't make an array of these types. */
814 if (TREE_CODE (elttype
) == REFERENCE_TYPE
815 || TREE_CODE (elttype
) == FUNCTION_TYPE
816 || VOID_TYPE_P (elttype
))
819 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
822 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
823 false, flags
, complain
);
830 t
= alloc_conversion (ck_list
);
832 t
->u
.list
= subconvs
;
835 for (i
= 0; i
< len
; ++i
)
837 conversion
*sub
= subconvs
[i
];
838 if (sub
->rank
> t
->rank
)
840 if (sub
->user_conv_p
)
841 t
->user_conv_p
= true;
849 /* Return the next conversion of the conversion chain (if applicable),
850 or NULL otherwise. Please use this function instead of directly
851 accessing fields of struct conversion. */
854 next_conversion (conversion
*conv
)
857 || conv
->kind
== ck_identity
858 || conv
->kind
== ck_ambig
859 || conv
->kind
== ck_list
)
864 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
865 is a valid aggregate initializer for array type ATYPE. */
868 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
871 tree elttype
= TREE_TYPE (atype
);
872 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
874 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
876 if (TREE_CODE (elttype
) == ARRAY_TYPE
877 && TREE_CODE (val
) == CONSTRUCTOR
)
878 ok
= can_convert_array (elttype
, val
, flags
, complain
);
880 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
888 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
889 aggregate class, if such a conversion is possible. */
892 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
894 unsigned HOST_WIDE_INT i
= 0;
896 tree field
= next_initializable_field (TYPE_FIELDS (type
));
897 tree empty_ctor
= NULL_TREE
;
899 /* We already called reshape_init in implicit_conversion. */
901 /* The conversions within the init-list aren't affected by the enclosing
902 context; they're always simple copy-initialization. */
903 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
905 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
907 tree ftype
= TREE_TYPE (field
);
911 if (i
< CONSTRUCTOR_NELTS (ctor
))
912 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
913 else if (TREE_CODE (ftype
) == REFERENCE_TYPE
)
914 /* Value-initialization of reference is ill-formed. */
918 if (empty_ctor
== NULL_TREE
)
919 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
924 if (TREE_CODE (ftype
) == ARRAY_TYPE
925 && TREE_CODE (val
) == CONSTRUCTOR
)
926 ok
= can_convert_array (ftype
, val
, flags
, complain
);
928 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
934 if (TREE_CODE (type
) == UNION_TYPE
)
938 if (i
< CONSTRUCTOR_NELTS (ctor
))
941 c
= alloc_conversion (ck_aggr
);
944 c
->user_conv_p
= true;
945 c
->check_narrowing
= true;
950 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
951 array type, if such a conversion is possible. */
954 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
957 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
958 tree elttype
= TREE_TYPE (type
);
963 enum conversion_rank rank
= cr_exact
;
965 /* We might need to propagate the size from the element to the array. */
966 complete_type (type
);
968 if (TYPE_DOMAIN (type
)
969 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
971 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
976 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
978 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
981 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
982 false, flags
, complain
);
986 if (sub
->rank
> rank
)
988 if (sub
->user_conv_p
)
994 c
= alloc_conversion (ck_aggr
);
997 c
->user_conv_p
= user
;
1003 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1004 complex type, if such a conversion is possible. */
1007 build_complex_conv (tree type
, tree ctor
, int flags
,
1008 tsubst_flags_t complain
)
1011 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1012 tree elttype
= TREE_TYPE (type
);
1017 enum conversion_rank rank
= cr_exact
;
1022 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1024 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1027 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1028 false, flags
, complain
);
1032 if (sub
->rank
> rank
)
1034 if (sub
->user_conv_p
)
1040 c
= alloc_conversion (ck_aggr
);
1043 c
->user_conv_p
= user
;
1049 /* Build a representation of the identity conversion from EXPR to
1050 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1053 build_identity_conv (tree type
, tree expr
)
1057 c
= alloc_conversion (ck_identity
);
1064 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1065 were multiple user-defined conversions to accomplish the job.
1066 Build a conversion that indicates that ambiguity. */
1069 build_ambiguous_conv (tree type
, tree expr
)
1073 c
= alloc_conversion (ck_ambig
);
1081 strip_top_quals (tree t
)
1083 if (TREE_CODE (t
) == ARRAY_TYPE
)
1085 return cp_build_qualified_type (t
, 0);
1088 /* Returns the standard conversion path (see [conv]) from type FROM to type
1089 TO, if any. For proper handling of null pointer constants, you must
1090 also pass the expression EXPR to convert from. If C_CAST_P is true,
1091 this conversion is coming from a C-style cast. */
1094 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1097 enum tree_code fcode
, tcode
;
1099 bool fromref
= false;
1102 to
= non_reference (to
);
1103 if (TREE_CODE (from
) == REFERENCE_TYPE
)
1106 from
= TREE_TYPE (from
);
1109 to
= strip_top_quals (to
);
1110 from
= strip_top_quals (from
);
1112 if (expr
&& type_unknown_p (expr
))
1114 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1116 tsubst_flags_t tflags
= tf_conv
;
1117 expr
= instantiate_type (to
, expr
, tflags
);
1118 if (expr
== error_mark_node
)
1120 from
= TREE_TYPE (expr
);
1122 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1124 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1125 expr
= resolve_nondeduced_context (expr
);
1126 from
= TREE_TYPE (expr
);
1130 fcode
= TREE_CODE (from
);
1131 tcode
= TREE_CODE (to
);
1133 conv
= build_identity_conv (from
, expr
);
1134 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1136 from
= type_decays_to (from
);
1137 fcode
= TREE_CODE (from
);
1138 conv
= build_conv (ck_lvalue
, from
, conv
);
1140 else if (fromref
|| (expr
&& lvalue_p (expr
)))
1145 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1148 from
= strip_top_quals (bitfield_type
);
1149 fcode
= TREE_CODE (from
);
1152 conv
= build_conv (ck_rvalue
, from
, conv
);
1153 if (flags
& LOOKUP_PREFER_RVALUE
)
1154 conv
->rvaluedness_matches_p
= true;
1157 /* Allow conversion between `__complex__' data types. */
1158 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1160 /* The standard conversion sequence to convert FROM to TO is
1161 the standard conversion sequence to perform componentwise
1163 conversion
*part_conv
= standard_conversion
1164 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
);
1168 conv
= build_conv (part_conv
->kind
, to
, conv
);
1169 conv
->rank
= part_conv
->rank
;
1177 if (same_type_p (from
, to
))
1179 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1180 conv
->type
= qualified_to
;
1185 A null pointer constant can be converted to a pointer type; ... A
1186 null pointer constant of integral type can be converted to an
1187 rvalue of type std::nullptr_t. */
1188 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1189 || NULLPTR_TYPE_P (to
))
1190 && ((expr
&& null_ptr_cst_p (expr
))
1191 || NULLPTR_TYPE_P (from
)))
1192 conv
= build_conv (ck_std
, to
, conv
);
1193 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1194 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1196 /* For backwards brain damage compatibility, allow interconversion of
1197 pointers and integers with a pedwarn. */
1198 conv
= build_conv (ck_std
, to
, conv
);
1201 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1203 /* For backwards brain damage compatibility, allow interconversion of
1204 enums and integers with a pedwarn. */
1205 conv
= build_conv (ck_std
, to
, conv
);
1208 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1209 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1214 if (tcode
== POINTER_TYPE
1215 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from
),
1218 else if (VOID_TYPE_P (TREE_TYPE (to
))
1219 && !TYPE_PTRDATAMEM_P (from
)
1220 && TREE_CODE (TREE_TYPE (from
)) != FUNCTION_TYPE
)
1222 tree nfrom
= TREE_TYPE (from
);
1223 /* Don't try to apply restrict to void. */
1224 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1225 from
= build_pointer_type
1226 (cp_build_qualified_type (void_type_node
, quals
));
1227 conv
= build_conv (ck_ptr
, from
, conv
);
1229 else if (TYPE_PTRDATAMEM_P (from
))
1231 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1232 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1234 if (DERIVED_FROM_P (fbase
, tbase
)
1235 && (same_type_ignoring_top_level_qualifiers_p
1236 (TYPE_PTRMEM_POINTED_TO_TYPE (from
),
1237 TYPE_PTRMEM_POINTED_TO_TYPE (to
))))
1239 from
= build_ptrmem_type (tbase
,
1240 TYPE_PTRMEM_POINTED_TO_TYPE (from
));
1241 conv
= build_conv (ck_pmem
, from
, conv
);
1243 else if (!same_type_p (fbase
, tbase
))
1246 else if (CLASS_TYPE_P (TREE_TYPE (from
))
1247 && CLASS_TYPE_P (TREE_TYPE (to
))
1250 An rvalue of type "pointer to cv D," where D is a
1251 class type, can be converted to an rvalue of type
1252 "pointer to cv B," where B is a base class (clause
1253 _class.derived_) of D. If B is an inaccessible
1254 (clause _class.access_) or ambiguous
1255 (_class.member.lookup_) base class of D, a program
1256 that necessitates this conversion is ill-formed.
1257 Therefore, we use DERIVED_FROM_P, and do not check
1258 access or uniqueness. */
1259 && DERIVED_FROM_P (TREE_TYPE (to
), TREE_TYPE (from
)))
1262 cp_build_qualified_type (TREE_TYPE (to
),
1263 cp_type_quals (TREE_TYPE (from
)));
1264 from
= build_pointer_type (from
);
1265 conv
= build_conv (ck_ptr
, from
, conv
);
1266 conv
->base_p
= true;
1269 if (tcode
== POINTER_TYPE
)
1271 to_pointee
= TREE_TYPE (to
);
1272 from_pointee
= TREE_TYPE (from
);
1276 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1277 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1280 if (same_type_p (from
, to
))
1282 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1283 /* In a C-style cast, we ignore CV-qualification because we
1284 are allowed to perform a static_cast followed by a
1286 conv
= build_conv (ck_qual
, to
, conv
);
1287 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1288 conv
= build_conv (ck_qual
, to
, conv
);
1289 else if (expr
&& string_conv_p (to
, expr
, 0))
1290 /* converting from string constant to char *. */
1291 conv
= build_conv (ck_qual
, to
, conv
);
1292 /* Allow conversions among compatible ObjC pointer types (base
1293 conversions have been already handled above). */
1294 else if (c_dialect_objc ()
1295 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1296 conv
= build_conv (ck_ptr
, to
, conv
);
1297 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1299 conv
= build_conv (ck_ptr
, to
, conv
);
1307 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1309 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1310 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1311 tree fbase
= class_of_this_parm (fromfn
);
1312 tree tbase
= class_of_this_parm (tofn
);
1314 if (!DERIVED_FROM_P (fbase
, tbase
)
1315 || !same_type_p (static_fn_type (fromfn
),
1316 static_fn_type (tofn
)))
1319 from
= build_memfn_type (fromfn
,
1321 cp_type_quals (tbase
),
1322 type_memfn_rqual (tofn
));
1323 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1324 conv
= build_conv (ck_pmem
, from
, conv
);
1325 conv
->base_p
= true;
1327 else if (tcode
== BOOLEAN_TYPE
)
1331 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1332 to member type can be converted to a prvalue of type bool. ...
1333 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1334 std::nullptr_t can be converted to a prvalue of type bool; */
1335 if (ARITHMETIC_TYPE_P (from
)
1336 || UNSCOPED_ENUM_P (from
)
1337 || fcode
== POINTER_TYPE
1338 || TYPE_PTRMEM_P (from
)
1339 || NULLPTR_TYPE_P (from
))
1341 conv
= build_conv (ck_std
, to
, conv
);
1342 if (fcode
== POINTER_TYPE
1343 || TYPE_PTRDATAMEM_P (from
)
1344 || (TYPE_PTRMEMFUNC_P (from
)
1345 && conv
->rank
< cr_pbool
)
1346 || NULLPTR_TYPE_P (from
))
1347 conv
->rank
= cr_pbool
;
1348 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1355 /* We don't check for ENUMERAL_TYPE here because there are no standard
1356 conversions to enum type. */
1357 /* As an extension, allow conversion to complex type. */
1358 else if (ARITHMETIC_TYPE_P (to
))
1360 if (! (INTEGRAL_CODE_P (fcode
)
1361 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1362 || SCOPED_ENUM_P (from
))
1364 conv
= build_conv (ck_std
, to
, conv
);
1366 /* Give this a better rank if it's a promotion. */
1367 if (same_type_p (to
, type_promotes_to (from
))
1368 && next_conversion (conv
)->rank
<= cr_promotion
)
1369 conv
->rank
= cr_promotion
;
1371 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1372 && vector_types_convertible_p (from
, to
, false))
1373 return build_conv (ck_std
, to
, conv
);
1374 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1375 && is_properly_derived_from (from
, to
))
1377 if (conv
->kind
== ck_rvalue
)
1378 conv
= next_conversion (conv
);
1379 conv
= build_conv (ck_base
, to
, conv
);
1380 /* The derived-to-base conversion indicates the initialization
1381 of a parameter with base type from an object of a derived
1382 type. A temporary object is created to hold the result of
1383 the conversion unless we're binding directly to a reference. */
1384 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1389 if (flags
& LOOKUP_NO_NARROWING
)
1390 conv
->check_narrowing
= true;
1395 /* Returns nonzero if T1 is reference-related to T2. */
1398 reference_related_p (tree t1
, tree t2
)
1400 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1403 t1
= TYPE_MAIN_VARIANT (t1
);
1404 t2
= TYPE_MAIN_VARIANT (t2
);
1408 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1409 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1411 return (same_type_p (t1
, t2
)
1412 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1413 && DERIVED_FROM_P (t1
, t2
)));
1416 /* Returns nonzero if T1 is reference-compatible with T2. */
1419 reference_compatible_p (tree t1
, tree t2
)
1423 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1424 reference-related to T2 and cv1 is the same cv-qualification as,
1425 or greater cv-qualification than, cv2. */
1426 return (reference_related_p (t1
, t2
)
1427 && at_least_as_qualified_p (t1
, t2
));
1430 /* A reference of the indicated TYPE is being bound directly to the
1431 expression represented by the implicit conversion sequence CONV.
1432 Return a conversion sequence for this binding. */
1435 direct_reference_binding (tree type
, conversion
*conv
)
1439 gcc_assert (TREE_CODE (type
) == REFERENCE_TYPE
);
1440 gcc_assert (TREE_CODE (conv
->type
) != REFERENCE_TYPE
);
1442 t
= TREE_TYPE (type
);
1446 When a parameter of reference type binds directly
1447 (_dcl.init.ref_) to an argument expression, the implicit
1448 conversion sequence is the identity conversion, unless the
1449 argument expression has a type that is a derived class of the
1450 parameter type, in which case the implicit conversion sequence is
1451 a derived-to-base Conversion.
1453 If the parameter binds directly to the result of applying a
1454 conversion function to the argument expression, the implicit
1455 conversion sequence is a user-defined conversion sequence
1456 (_over.ics.user_), with the second standard conversion sequence
1457 either an identity conversion or, if the conversion function
1458 returns an entity of a type that is a derived class of the
1459 parameter type, a derived-to-base conversion. */
1460 if (!same_type_ignoring_top_level_qualifiers_p (t
, conv
->type
))
1462 /* Represent the derived-to-base conversion. */
1463 conv
= build_conv (ck_base
, t
, conv
);
1464 /* We will actually be binding to the base-class subobject in
1465 the derived class, so we mark this conversion appropriately.
1466 That way, convert_like knows not to generate a temporary. */
1467 conv
->need_temporary_p
= false;
1469 return build_conv (ck_ref_bind
, type
, conv
);
1472 /* Returns the conversion path from type FROM to reference type TO for
1473 purposes of reference binding. For lvalue binding, either pass a
1474 reference type to FROM or an lvalue expression to EXPR. If the
1475 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1476 the conversion returned. If C_CAST_P is true, this
1477 conversion is coming from a C-style cast. */
1480 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1481 tsubst_flags_t complain
)
1483 conversion
*conv
= NULL
;
1484 tree to
= TREE_TYPE (rto
);
1489 cp_lvalue_kind gl_kind
;
1492 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1494 expr
= instantiate_type (to
, expr
, tf_none
);
1495 if (expr
== error_mark_node
)
1497 from
= TREE_TYPE (expr
);
1500 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1502 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1503 /* DR 1288: Otherwise, if the initializer list has a single element
1504 of type E and ... [T's] referenced type is reference-related to E,
1505 the object or reference is initialized from that element... */
1506 if (CONSTRUCTOR_NELTS (expr
) == 1)
1508 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1509 if (error_operand_p (elt
))
1511 tree etype
= TREE_TYPE (elt
);
1512 if (reference_related_p (to
, etype
))
1519 /* Otherwise, if T is a reference type, a prvalue temporary of the
1520 type referenced by T is copy-list-initialized or
1521 direct-list-initialized, depending on the kind of initialization
1522 for the reference, and the reference is bound to that temporary. */
1523 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1524 flags
|LOOKUP_NO_TEMP_BIND
, complain
);
1528 if (TREE_CODE (from
) == REFERENCE_TYPE
)
1530 from
= TREE_TYPE (from
);
1531 if (!TYPE_REF_IS_RVALUE (rfrom
)
1532 || TREE_CODE (from
) == FUNCTION_TYPE
)
1533 gl_kind
= clk_ordinary
;
1535 gl_kind
= clk_rvalueref
;
1539 gl_kind
= lvalue_kind (expr
);
1540 if (gl_kind
& clk_class
)
1541 /* A class prvalue is not a glvalue. */
1546 is_lvalue
= gl_kind
&& !(gl_kind
& clk_rvalueref
);
1549 if ((gl_kind
& clk_bitfield
) != 0)
1550 tfrom
= unlowered_expr_type (expr
);
1552 /* Figure out whether or not the types are reference-related and
1553 reference compatible. We have to do this after stripping
1554 references from FROM. */
1555 related_p
= reference_related_p (to
, tfrom
);
1556 /* If this is a C cast, first convert to an appropriately qualified
1557 type, so that we can later do a const_cast to the desired type. */
1558 if (related_p
&& c_cast_p
1559 && !at_least_as_qualified_p (to
, tfrom
))
1560 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1561 compatible_p
= reference_compatible_p (to
, tfrom
);
1563 /* Directly bind reference when target expression's type is compatible with
1564 the reference and expression is an lvalue. In DR391, the wording in
1565 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1566 const and rvalue references to rvalues of compatible class type.
1567 We should also do direct bindings for non-class xvalues. */
1570 || (!(flags
& LOOKUP_NO_TEMP_BIND
)
1571 && (CLASS_TYPE_P (from
)
1572 || TREE_CODE (from
) == ARRAY_TYPE
))))
1576 If the initializer expression
1578 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1579 is reference-compatible with "cv2 T2,"
1581 the reference is bound directly to the initializer expression
1585 If the initializer expression is an rvalue, with T2 a class type,
1586 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1587 is bound to the object represented by the rvalue or to a sub-object
1588 within that object. */
1590 conv
= build_identity_conv (tfrom
, expr
);
1591 conv
= direct_reference_binding (rto
, conv
);
1593 if (flags
& LOOKUP_PREFER_RVALUE
)
1594 /* The top-level caller requested that we pretend that the lvalue
1595 be treated as an rvalue. */
1596 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1597 else if (TREE_CODE (rfrom
) == REFERENCE_TYPE
)
1598 /* Handle rvalue reference to function properly. */
1599 conv
->rvaluedness_matches_p
1600 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1602 conv
->rvaluedness_matches_p
1603 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1605 if ((gl_kind
& clk_bitfield
) != 0
1606 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1607 /* For the purposes of overload resolution, we ignore the fact
1608 this expression is a bitfield or packed field. (In particular,
1609 [over.ics.ref] says specifically that a function with a
1610 non-const reference parameter is viable even if the
1611 argument is a bitfield.)
1613 However, when we actually call the function we must create
1614 a temporary to which to bind the reference. If the
1615 reference is volatile, or isn't const, then we cannot make
1616 a temporary, so we just issue an error when the conversion
1618 conv
->need_temporary_p
= true;
1620 /* Don't allow binding of lvalues (other than function lvalues) to
1621 rvalue references. */
1622 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1623 && TREE_CODE (to
) != FUNCTION_TYPE
1624 && !(flags
& LOOKUP_PREFER_RVALUE
))
1627 /* Nor the reverse. */
1628 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1629 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1630 || (flags
& LOOKUP_NO_RVAL_BIND
))
1631 && TREE_CODE (to
) != FUNCTION_TYPE
)
1639 /* [class.conv.fct] A conversion function is never used to convert a
1640 (possibly cv-qualified) object to the (possibly cv-qualified) same
1641 object type (or a reference to it), to a (possibly cv-qualified) base
1642 class of that type (or a reference to it).... */
1643 else if (CLASS_TYPE_P (from
) && !related_p
1644 && !(flags
& LOOKUP_NO_CONVERSION
))
1648 If the initializer expression
1650 -- has a class type (i.e., T2 is a class type) can be
1651 implicitly converted to an lvalue of type "cv3 T3," where
1652 "cv1 T1" is reference-compatible with "cv3 T3". (this
1653 conversion is selected by enumerating the applicable
1654 conversion functions (_over.match.ref_) and choosing the
1655 best one through overload resolution. (_over.match_).
1657 the reference is bound to the lvalue result of the conversion
1658 in the second case. */
1659 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1662 return cand
->second_conv
;
1665 /* From this point on, we conceptually need temporaries, even if we
1666 elide them. Only the cases above are "direct bindings". */
1667 if (flags
& LOOKUP_NO_TEMP_BIND
)
1672 When a parameter of reference type is not bound directly to an
1673 argument expression, the conversion sequence is the one required
1674 to convert the argument expression to the underlying type of the
1675 reference according to _over.best.ics_. Conceptually, this
1676 conversion sequence corresponds to copy-initializing a temporary
1677 of the underlying type with the argument expression. Any
1678 difference in top-level cv-qualification is subsumed by the
1679 initialization itself and does not constitute a conversion. */
1683 Otherwise, the reference shall be an lvalue reference to a
1684 non-volatile const type, or the reference shall be an rvalue
1687 We try below to treat this as a bad conversion to improve diagnostics,
1688 but if TO is an incomplete class, we need to reject this conversion
1689 now to avoid unnecessary instantiation. */
1690 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1691 && !COMPLETE_TYPE_P (to
))
1694 /* We're generating a temporary now, but don't bind any more in the
1695 conversion (specifically, don't slice the temporary returned by a
1696 conversion operator). */
1697 flags
|= LOOKUP_NO_TEMP_BIND
;
1699 /* Core issue 899: When [copy-]initializing a temporary to be bound
1700 to the first parameter of a copy constructor (12.8) called with
1701 a single argument in the context of direct-initialization,
1702 explicit conversion functions are also considered.
1704 So don't set LOOKUP_ONLYCONVERTING in that case. */
1705 if (!(flags
& LOOKUP_COPY_PARM
))
1706 flags
|= LOOKUP_ONLYCONVERTING
;
1709 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1714 if (conv
->user_conv_p
)
1716 /* If initializing the temporary used a conversion function,
1717 recalculate the second conversion sequence. */
1718 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1719 if (t
->kind
== ck_user
1720 && DECL_CONV_FN_P (t
->cand
->fn
))
1722 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1723 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1724 conversion
*new_second
1725 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1729 return merge_conversion_sequences (t
, new_second
);
1733 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1734 /* This reference binding, unlike those above, requires the
1735 creation of a temporary. */
1736 conv
->need_temporary_p
= true;
1737 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1741 Otherwise, the reference shall be an lvalue reference to a
1742 non-volatile const type, or the reference shall be an rvalue
1744 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1749 Otherwise, a temporary of type "cv1 T1" is created and
1750 initialized from the initializer expression using the rules for a
1751 non-reference copy initialization. If T1 is reference-related to
1752 T2, cv1 must be the same cv-qualification as, or greater
1753 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1754 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1760 /* Returns the implicit conversion sequence (see [over.ics]) from type
1761 FROM to type TO. The optional expression EXPR may affect the
1762 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1763 true, this conversion is coming from a C-style cast. */
1766 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1767 int flags
, tsubst_flags_t complain
)
1771 if (from
== error_mark_node
|| to
== error_mark_node
1772 || expr
== error_mark_node
)
1775 /* Other flags only apply to the primary function in overload
1776 resolution, or after we've chosen one. */
1777 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1778 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1779 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1781 /* FIXME: actually we don't want warnings either, but we can't just
1782 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1783 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1784 We really ought not to issue that warning until we've committed
1785 to that conversion. */
1786 complain
&= ~tf_error
;
1788 /* Call reshape_init early to remove redundant braces. */
1789 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1790 && CLASS_TYPE_P (to
)
1791 && COMPLETE_TYPE_P (complete_type (to
))
1792 && !CLASSTYPE_NON_AGGREGATE (to
))
1794 expr
= reshape_init (to
, expr
, complain
);
1795 if (expr
== error_mark_node
)
1797 from
= TREE_TYPE (expr
);
1800 if (TREE_CODE (to
) == REFERENCE_TYPE
)
1801 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1803 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
);
1808 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1810 if (is_std_init_list (to
))
1811 return build_list_conv (to
, expr
, flags
, complain
);
1813 /* As an extension, allow list-initialization of _Complex. */
1814 if (TREE_CODE (to
) == COMPLEX_TYPE
)
1816 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1821 /* Allow conversion from an initializer-list with one element to a
1823 if (SCALAR_TYPE_P (to
))
1825 int nelts
= CONSTRUCTOR_NELTS (expr
);
1829 elt
= build_value_init (to
, tf_none
);
1830 else if (nelts
== 1)
1831 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1833 elt
= error_mark_node
;
1835 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1836 c_cast_p
, flags
, complain
);
1839 conv
->check_narrowing
= true;
1840 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1841 /* Too many levels of braces, i.e. '{{1}}'. */
1846 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1847 return build_array_conv (to
, expr
, flags
, complain
);
1850 if (expr
!= NULL_TREE
1851 && (MAYBE_CLASS_TYPE_P (from
)
1852 || MAYBE_CLASS_TYPE_P (to
))
1853 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1855 struct z_candidate
*cand
;
1857 if (CLASS_TYPE_P (to
)
1858 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1859 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1860 return build_aggr_conv (to
, expr
, flags
, complain
);
1862 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
1864 conv
= cand
->second_conv
;
1866 /* We used to try to bind a reference to a temporary here, but that
1867 is now handled after the recursive call to this function at the end
1868 of reference_binding. */
1875 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1876 functions. ARGS will not be changed until a single candidate is
1879 static struct z_candidate
*
1880 add_candidate (struct z_candidate
**candidates
,
1881 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
1882 size_t num_convs
, conversion
**convs
,
1883 tree access_path
, tree conversion_path
,
1884 int viable
, struct rejection_reason
*reason
,
1887 struct z_candidate
*cand
= (struct z_candidate
*)
1888 conversion_obstack_alloc (sizeof (struct z_candidate
));
1891 cand
->first_arg
= first_arg
;
1893 cand
->convs
= convs
;
1894 cand
->num_convs
= num_convs
;
1895 cand
->access_path
= access_path
;
1896 cand
->conversion_path
= conversion_path
;
1897 cand
->viable
= viable
;
1898 cand
->reason
= reason
;
1899 cand
->next
= *candidates
;
1900 cand
->flags
= flags
;
1906 /* Return the number of remaining arguments in the parameter list
1907 beginning with ARG. */
1910 remaining_arguments (tree arg
)
1914 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
1915 arg
= TREE_CHAIN (arg
))
1921 /* Create an overload candidate for the function or method FN called
1922 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1923 FLAGS is passed on to implicit_conversion.
1925 This does not change ARGS.
1927 CTYPE, if non-NULL, is the type we want to pretend this function
1928 comes from for purposes of overload resolution. */
1930 static struct z_candidate
*
1931 add_function_candidate (struct z_candidate
**candidates
,
1932 tree fn
, tree ctype
, tree first_arg
,
1933 const vec
<tree
, va_gc
> *args
, tree access_path
,
1934 tree conversion_path
, int flags
,
1935 tsubst_flags_t complain
)
1937 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
1941 tree orig_first_arg
= first_arg
;
1944 struct rejection_reason
*reason
= NULL
;
1946 /* At this point we should not see any functions which haven't been
1947 explicitly declared, except for friend functions which will have
1948 been found using argument dependent lookup. */
1949 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
1951 /* The `this', `in_chrg' and VTT arguments to constructors are not
1952 considered in overload resolution. */
1953 if (DECL_CONSTRUCTOR_P (fn
))
1955 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
1956 skip
= num_artificial_parms_for (fn
);
1957 if (skip
> 0 && first_arg
!= NULL_TREE
)
1960 first_arg
= NULL_TREE
;
1966 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
1967 convs
= alloc_conversions (len
);
1969 /* 13.3.2 - Viable functions [over.match.viable]
1970 First, to be a viable function, a candidate function shall have enough
1971 parameters to agree in number with the arguments in the list.
1973 We need to check this first; otherwise, checking the ICSes might cause
1974 us to produce an ill-formed template instantiation. */
1976 parmnode
= parmlist
;
1977 for (i
= 0; i
< len
; ++i
)
1979 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
1981 parmnode
= TREE_CHAIN (parmnode
);
1984 if ((i
< len
&& parmnode
)
1985 || !sufficient_parms_p (parmnode
))
1987 int remaining
= remaining_arguments (parmnode
);
1989 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
1992 /* Second, for a function to be viable, its constraints must be
1994 if (flag_concepts
&& viable
1995 && !constraints_satisfied_p (fn
))
1997 reason
= constraint_failure (fn
);
2001 /* When looking for a function from a subobject from an implicit
2002 copy/move constructor/operator=, don't consider anything that takes (a
2003 reference to) an unrelated type. See c++/44909 and core 1092. */
2004 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2006 if (DECL_CONSTRUCTOR_P (fn
))
2008 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2009 && DECL_OVERLOADED_OPERATOR_P (fn
) == NOP_EXPR
)
2015 parmnode
= chain_index (i
-1, parmlist
);
2016 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2021 /* This only applies at the top level. */
2022 flags
&= ~LOOKUP_DEFAULTED
;
2028 /* Third, for F to be a viable function, there shall exist for each
2029 argument an implicit conversion sequence that converts that argument
2030 to the corresponding parameter of F. */
2032 parmnode
= parmlist
;
2034 for (i
= 0; i
< len
; ++i
)
2036 tree argtype
, to_type
;
2041 if (parmnode
== void_list_node
)
2044 if (i
== 0 && first_arg
!= NULL_TREE
)
2047 arg
= CONST_CAST_TREE (
2048 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2049 argtype
= lvalue_type (arg
);
2051 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2052 && ! DECL_CONSTRUCTOR_P (fn
));
2056 tree parmtype
= TREE_VALUE (parmnode
);
2059 parmnode
= TREE_CHAIN (parmnode
);
2061 /* The type of the implicit object parameter ('this') for
2062 overload resolution is not always the same as for the
2063 function itself; conversion functions are considered to
2064 be members of the class being converted, and functions
2065 introduced by a using-declaration are considered to be
2066 members of the class that uses them.
2068 Since build_over_call ignores the ICS for the `this'
2069 parameter, we can just change the parm type. */
2070 if (ctype
&& is_this
)
2072 parmtype
= cp_build_qualified_type
2073 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2074 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2076 /* If the function has a ref-qualifier, the implicit
2077 object parameter has reference type. */
2078 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2079 parmtype
= cp_build_reference_type (parmtype
, rv
);
2080 /* The special handling of 'this' conversions in compare_ics
2081 does not apply if there is a ref-qualifier. */
2086 parmtype
= build_pointer_type (parmtype
);
2087 arg
= build_this (arg
);
2088 argtype
= lvalue_type (arg
);
2092 /* Core issue 899: When [copy-]initializing a temporary to be bound
2093 to the first parameter of a copy constructor (12.8) called with
2094 a single argument in the context of direct-initialization,
2095 explicit conversion functions are also considered.
2097 So set LOOKUP_COPY_PARM to let reference_binding know that
2098 it's being called in that context. We generalize the above
2099 to handle move constructors and template constructors as well;
2100 the standardese should soon be updated similarly. */
2101 if (ctype
&& i
== 0 && (len
-skip
== 1)
2102 && DECL_CONSTRUCTOR_P (fn
)
2103 && parmtype
!= error_mark_node
2104 && (same_type_ignoring_top_level_qualifiers_p
2105 (non_reference (parmtype
), ctype
)))
2107 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2108 lflags
|= LOOKUP_COPY_PARM
;
2109 /* We allow user-defined conversions within init-lists, but
2110 don't list-initialize the copy parm, as that would mean
2111 using two levels of braces for the same type. */
2112 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2113 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2114 lflags
|= LOOKUP_NO_CONVERSION
;
2117 lflags
|= LOOKUP_ONLYCONVERTING
;
2119 t
= implicit_conversion (parmtype
, argtype
, arg
,
2120 /*c_cast_p=*/false, lflags
, complain
);
2125 t
= build_identity_conv (argtype
, arg
);
2126 t
->ellipsis_p
= true;
2137 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
);
2144 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
);
2149 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2150 access_path
, conversion_path
, viable
, reason
, flags
);
2153 /* Create an overload candidate for the conversion function FN which will
2154 be invoked for expression OBJ, producing a pointer-to-function which
2155 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2156 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2157 passed on to implicit_conversion.
2159 Actually, we don't really care about FN; we care about the type it
2160 converts to. There may be multiple conversion functions that will
2161 convert to that type, and we rely on build_user_type_conversion_1 to
2162 choose the best one; so when we create our candidate, we record the type
2163 instead of the function. */
2165 static struct z_candidate
*
2166 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2167 tree first_arg
, const vec
<tree
, va_gc
> *arglist
,
2168 tree access_path
, tree conversion_path
,
2169 tsubst_flags_t complain
)
2171 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2172 int i
, len
, viable
, flags
;
2173 tree parmlist
, parmnode
;
2175 struct rejection_reason
*reason
;
2177 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2178 parmlist
= TREE_TYPE (parmlist
);
2179 parmlist
= TYPE_ARG_TYPES (parmlist
);
2181 len
= vec_safe_length (arglist
) + (first_arg
!= NULL_TREE
? 1 : 0) + 1;
2182 convs
= alloc_conversions (len
);
2183 parmnode
= parmlist
;
2185 flags
= LOOKUP_IMPLICIT
;
2188 /* Don't bother looking up the same type twice. */
2189 if (*candidates
&& (*candidates
)->fn
== totype
)
2192 for (i
= 0; i
< len
; ++i
)
2194 tree arg
, argtype
, convert_type
= NULL_TREE
;
2199 else if (i
== 1 && first_arg
!= NULL_TREE
)
2202 arg
= (*arglist
)[i
- (first_arg
!= NULL_TREE
? 1 : 0) - 1];
2203 argtype
= lvalue_type (arg
);
2207 t
= implicit_conversion (totype
, argtype
, arg
, /*c_cast_p=*/false,
2209 convert_type
= totype
;
2211 else if (parmnode
== void_list_node
)
2215 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2216 /*c_cast_p=*/false, flags
, complain
);
2217 convert_type
= TREE_VALUE (parmnode
);
2221 t
= build_identity_conv (argtype
, arg
);
2222 t
->ellipsis_p
= true;
2223 convert_type
= argtype
;
2233 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
);
2240 parmnode
= TREE_CHAIN (parmnode
);
2244 || ! sufficient_parms_p (parmnode
))
2246 int remaining
= remaining_arguments (parmnode
);
2248 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2251 return add_candidate (candidates
, totype
, first_arg
, arglist
, len
, convs
,
2252 access_path
, conversion_path
, viable
, reason
, flags
);
2256 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2257 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2258 int flags
, tsubst_flags_t complain
)
2265 struct rejection_reason
*reason
= NULL
;
2270 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2271 convs
= alloc_conversions (num_convs
);
2273 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2274 conversion ops are allowed. We handle that here by just checking for
2275 boolean_type_node because other operators don't ask for it. COND_EXPR
2276 also does contextual conversion to bool for the first operand, but we
2277 handle that in build_conditional_expr, and type1 here is operand 2. */
2278 if (type1
!= boolean_type_node
)
2279 flags
|= LOOKUP_ONLYCONVERTING
;
2281 for (i
= 0; i
< 2; ++i
)
2286 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2287 /*c_cast_p=*/false, flags
, complain
);
2291 /* We need something for printing the candidate. */
2292 t
= build_identity_conv (types
[i
], NULL_TREE
);
2293 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2299 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2305 /* For COND_EXPR we rearranged the arguments; undo that now. */
2308 convs
[2] = convs
[1];
2309 convs
[1] = convs
[0];
2310 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2311 /*c_cast_p=*/false, flags
,
2318 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2323 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2325 /*access_path=*/NULL_TREE
,
2326 /*conversion_path=*/NULL_TREE
,
2327 viable
, reason
, flags
);
2331 is_complete (tree t
)
2333 return COMPLETE_TYPE_P (complete_type (t
));
2336 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2339 promoted_arithmetic_type_p (tree type
)
2343 In this section, the term promoted integral type is used to refer
2344 to those integral types which are preserved by integral promotion
2345 (including e.g. int and long but excluding e.g. char).
2346 Similarly, the term promoted arithmetic type refers to promoted
2347 integral types plus floating types. */
2348 return ((CP_INTEGRAL_TYPE_P (type
)
2349 && same_type_p (type_promotes_to (type
), type
))
2350 || TREE_CODE (type
) == REAL_TYPE
);
2353 /* Create any builtin operator overload candidates for the operator in
2354 question given the converted operand types TYPE1 and TYPE2. The other
2355 args are passed through from add_builtin_candidates to
2356 build_builtin_candidate.
2358 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2359 If CODE is requires candidates operands of the same type of the kind
2360 of which TYPE1 and TYPE2 are, we add both candidates
2361 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2364 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2365 enum tree_code code2
, tree fnname
, tree type1
,
2366 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2367 tsubst_flags_t complain
)
2371 case POSTINCREMENT_EXPR
:
2372 case POSTDECREMENT_EXPR
:
2373 args
[1] = integer_zero_node
;
2374 type2
= integer_type_node
;
2383 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2384 and VQ is either volatile or empty, there exist candidate operator
2385 functions of the form
2386 VQ T& operator++(VQ T&);
2387 T operator++(VQ T&, int);
2388 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2389 type other than bool, and VQ is either volatile or empty, there exist
2390 candidate operator functions of the form
2391 VQ T& operator--(VQ T&);
2392 T operator--(VQ T&, int);
2393 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2394 complete object type, and VQ is either volatile or empty, there exist
2395 candidate operator functions of the form
2396 T*VQ& operator++(T*VQ&);
2397 T*VQ& operator--(T*VQ&);
2398 T* operator++(T*VQ&, int);
2399 T* operator--(T*VQ&, int); */
2401 case POSTDECREMENT_EXPR
:
2402 case PREDECREMENT_EXPR
:
2403 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2405 case POSTINCREMENT_EXPR
:
2406 case PREINCREMENT_EXPR
:
2407 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2409 type1
= build_reference_type (type1
);
2414 /* 7 For every cv-qualified or cv-unqualified object type T, there
2415 exist candidate operator functions of the form
2419 8 For every function type T, there exist candidate operator functions of
2421 T& operator*(T*); */
2424 if (TYPE_PTR_P (type1
)
2425 && (TYPE_PTROB_P (type1
)
2426 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2430 /* 9 For every type T, there exist candidate operator functions of the form
2433 10For every promoted arithmetic type T, there exist candidate operator
2434 functions of the form
2438 case UNARY_PLUS_EXPR
: /* unary + */
2439 if (TYPE_PTR_P (type1
))
2442 if (ARITHMETIC_TYPE_P (type1
))
2446 /* 11For every promoted integral type T, there exist candidate operator
2447 functions of the form
2451 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2455 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2456 is the same type as C2 or is a derived class of C2, T is a complete
2457 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2458 there exist candidate operator functions of the form
2459 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2460 where CV12 is the union of CV1 and CV2. */
2463 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2465 tree c1
= TREE_TYPE (type1
);
2466 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2468 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2469 && (TYPE_PTRMEMFUNC_P (type2
)
2470 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2475 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2476 didate operator functions of the form
2481 bool operator<(L, R);
2482 bool operator>(L, R);
2483 bool operator<=(L, R);
2484 bool operator>=(L, R);
2485 bool operator==(L, R);
2486 bool operator!=(L, R);
2487 where LR is the result of the usual arithmetic conversions between
2490 14For every pair of types T and I, where T is a cv-qualified or cv-
2491 unqualified complete object type and I is a promoted integral type,
2492 there exist candidate operator functions of the form
2493 T* operator+(T*, I);
2494 T& operator[](T*, I);
2495 T* operator-(T*, I);
2496 T* operator+(I, T*);
2497 T& operator[](I, T*);
2499 15For every T, where T is a pointer to complete object type, there exist
2500 candidate operator functions of the form112)
2501 ptrdiff_t operator-(T, T);
2503 16For every pointer or enumeration type T, there exist candidate operator
2504 functions of the form
2505 bool operator<(T, T);
2506 bool operator>(T, T);
2507 bool operator<=(T, T);
2508 bool operator>=(T, T);
2509 bool operator==(T, T);
2510 bool operator!=(T, T);
2512 17For every pointer to member type T, there exist candidate operator
2513 functions of the form
2514 bool operator==(T, T);
2515 bool operator!=(T, T); */
2518 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2520 if (TYPE_PTROB_P (type1
)
2521 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2523 type2
= ptrdiff_type_node
;
2527 case TRUNC_DIV_EXPR
:
2528 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2534 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2535 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2537 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2542 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2554 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2556 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2558 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2559 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2561 if (TYPE_PTR_P (type1
)
2562 && null_ptr_cst_p (args
[1]))
2567 if (null_ptr_cst_p (args
[0])
2568 && TYPE_PTR_P (type2
))
2576 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2579 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2581 type1
= ptrdiff_type_node
;
2584 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2586 type2
= ptrdiff_type_node
;
2591 /* 18For every pair of promoted integral types L and R, there exist candi-
2592 date operator functions of the form
2599 where LR is the result of the usual arithmetic conversions between
2602 case TRUNC_MOD_EXPR
:
2608 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2612 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2613 type, VQ is either volatile or empty, and R is a promoted arithmetic
2614 type, there exist candidate operator functions of the form
2615 VQ L& operator=(VQ L&, R);
2616 VQ L& operator*=(VQ L&, R);
2617 VQ L& operator/=(VQ L&, R);
2618 VQ L& operator+=(VQ L&, R);
2619 VQ L& operator-=(VQ L&, R);
2621 20For every pair T, VQ), where T is any type and VQ is either volatile
2622 or empty, there exist candidate operator functions of the form
2623 T*VQ& operator=(T*VQ&, T*);
2625 21For every pair T, VQ), where T is a pointer to member type and VQ is
2626 either volatile or empty, there exist candidate operator functions of
2628 VQ T& operator=(VQ T&, T);
2630 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2631 unqualified complete object type, VQ is either volatile or empty, and
2632 I is a promoted integral type, there exist candidate operator func-
2634 T*VQ& operator+=(T*VQ&, I);
2635 T*VQ& operator-=(T*VQ&, I);
2637 23For every triple L, VQ, R), where L is an integral or enumeration
2638 type, VQ is either volatile or empty, and R is a promoted integral
2639 type, there exist candidate operator functions of the form
2641 VQ L& operator%=(VQ L&, R);
2642 VQ L& operator<<=(VQ L&, R);
2643 VQ L& operator>>=(VQ L&, R);
2644 VQ L& operator&=(VQ L&, R);
2645 VQ L& operator^=(VQ L&, R);
2646 VQ L& operator|=(VQ L&, R); */
2653 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2655 type2
= ptrdiff_type_node
;
2659 case TRUNC_DIV_EXPR
:
2660 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2664 case TRUNC_MOD_EXPR
:
2670 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2675 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2677 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2678 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2679 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2680 || ((TYPE_PTRMEMFUNC_P (type1
)
2681 || TYPE_PTR_P (type1
))
2682 && null_ptr_cst_p (args
[1])))
2692 type1
= build_reference_type (type1
);
2698 For every pair of promoted arithmetic types L and R, there
2699 exist candidate operator functions of the form
2701 LR operator?(bool, L, R);
2703 where LR is the result of the usual arithmetic conversions
2704 between types L and R.
2706 For every type T, where T is a pointer or pointer-to-member
2707 type, there exist candidate operator functions of the form T
2708 operator?(bool, T, T); */
2710 if (promoted_arithmetic_type_p (type1
)
2711 && promoted_arithmetic_type_p (type2
))
2715 /* Otherwise, the types should be pointers. */
2716 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2719 /* We don't check that the two types are the same; the logic
2720 below will actually create two candidates; one in which both
2721 parameter types are TYPE1, and one in which both parameter
2727 if (ARITHMETIC_TYPE_P (type1
))
2735 /* Make sure we don't create builtin candidates with dependent types. */
2736 bool u1
= uses_template_parms (type1
);
2737 bool u2
= type2
? uses_template_parms (type2
) : false;
2740 /* Try to recover if one of the types is non-dependent. But if
2741 there's only one type, there's nothing we can do. */
2744 /* And we lose if both are dependent. */
2747 /* Or if they have different forms. */
2748 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2757 /* If we're dealing with two pointer types or two enumeral types,
2758 we need candidates for both of them. */
2759 if (type2
&& !same_type_p (type1
, type2
)
2760 && TREE_CODE (type1
) == TREE_CODE (type2
)
2761 && (TREE_CODE (type1
) == REFERENCE_TYPE
2762 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2763 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2764 || TYPE_PTRMEMFUNC_P (type1
)
2765 || MAYBE_CLASS_TYPE_P (type1
)
2766 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2768 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2770 tree cptype
= composite_pointer_type (type1
, type2
,
2775 if (cptype
!= error_mark_node
)
2777 build_builtin_candidate
2778 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
2784 build_builtin_candidate
2785 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
2786 build_builtin_candidate
2787 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
2791 build_builtin_candidate
2792 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
2796 type_decays_to (tree type
)
2798 if (TREE_CODE (type
) == ARRAY_TYPE
)
2799 return build_pointer_type (TREE_TYPE (type
));
2800 if (TREE_CODE (type
) == FUNCTION_TYPE
)
2801 return build_pointer_type (type
);
2805 /* There are three conditions of builtin candidates:
2807 1) bool-taking candidates. These are the same regardless of the input.
2808 2) pointer-pair taking candidates. These are generated for each type
2809 one of the input types converts to.
2810 3) arithmetic candidates. According to the standard, we should generate
2811 all of these, but I'm trying not to...
2813 Here we generate a superset of the possible candidates for this particular
2814 case. That is a subset of the full set the standard defines, plus some
2815 other cases which the standard disallows. add_builtin_candidate will
2816 filter out the invalid set. */
2819 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
2820 enum tree_code code2
, tree fnname
, tree
*args
,
2821 int flags
, tsubst_flags_t complain
)
2825 tree type
, argtypes
[3], t
;
2826 /* TYPES[i] is the set of possible builtin-operator parameter types
2827 we will consider for the Ith argument. */
2828 vec
<tree
, va_gc
> *types
[2];
2831 for (i
= 0; i
< 3; ++i
)
2834 argtypes
[i
] = unlowered_expr_type (args
[i
]);
2836 argtypes
[i
] = NULL_TREE
;
2841 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2842 and VQ is either volatile or empty, there exist candidate operator
2843 functions of the form
2844 VQ T& operator++(VQ T&); */
2846 case POSTINCREMENT_EXPR
:
2847 case PREINCREMENT_EXPR
:
2848 case POSTDECREMENT_EXPR
:
2849 case PREDECREMENT_EXPR
:
2854 /* 24There also exist candidate operator functions of the form
2855 bool operator!(bool);
2856 bool operator&&(bool, bool);
2857 bool operator||(bool, bool); */
2859 case TRUTH_NOT_EXPR
:
2860 build_builtin_candidate
2861 (candidates
, fnname
, boolean_type_node
,
2862 NULL_TREE
, args
, argtypes
, flags
, complain
);
2865 case TRUTH_ORIF_EXPR
:
2866 case TRUTH_ANDIF_EXPR
:
2867 build_builtin_candidate
2868 (candidates
, fnname
, boolean_type_node
,
2869 boolean_type_node
, args
, argtypes
, flags
, complain
);
2891 types
[0] = make_tree_vector ();
2892 types
[1] = make_tree_vector ();
2894 for (i
= 0; i
< 2; ++i
)
2898 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
2902 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
2905 convs
= lookup_conversions (argtypes
[i
]);
2907 if (code
== COND_EXPR
)
2909 if (real_lvalue_p (args
[i
]))
2910 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
2912 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
2918 for (; convs
; convs
= TREE_CHAIN (convs
))
2920 type
= TREE_TYPE (convs
);
2923 && (TREE_CODE (type
) != REFERENCE_TYPE
2924 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
2927 if (code
== COND_EXPR
&& TREE_CODE (type
) == REFERENCE_TYPE
)
2928 vec_safe_push (types
[i
], type
);
2930 type
= non_reference (type
);
2931 if (i
!= 0 || ! ref1
)
2933 type
= cv_unqualified (type_decays_to (type
));
2934 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
2935 vec_safe_push (types
[i
], type
);
2936 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
2937 type
= type_promotes_to (type
);
2940 if (! vec_member (type
, types
[i
]))
2941 vec_safe_push (types
[i
], type
);
2946 if (code
== COND_EXPR
&& real_lvalue_p (args
[i
]))
2947 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
2948 type
= non_reference (argtypes
[i
]);
2949 if (i
!= 0 || ! ref1
)
2951 type
= cv_unqualified (type_decays_to (type
));
2952 if (enum_p
&& UNSCOPED_ENUM_P (type
))
2953 vec_safe_push (types
[i
], type
);
2954 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
2955 type
= type_promotes_to (type
);
2957 vec_safe_push (types
[i
], type
);
2961 /* Run through the possible parameter types of both arguments,
2962 creating candidates with those parameter types. */
2963 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
2968 if (!types
[1]->is_empty ())
2969 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
2970 add_builtin_candidate
2971 (candidates
, code
, code2
, fnname
, t
,
2972 u
, args
, argtypes
, flags
, complain
);
2974 add_builtin_candidate
2975 (candidates
, code
, code2
, fnname
, t
,
2976 NULL_TREE
, args
, argtypes
, flags
, complain
);
2979 release_tree_vector (types
[0]);
2980 release_tree_vector (types
[1]);
2984 /* If TMPL can be successfully instantiated as indicated by
2985 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2987 TMPL is the template. EXPLICIT_TARGS are any explicit template
2988 arguments. ARGLIST is the arguments provided at the call-site.
2989 This does not change ARGLIST. The RETURN_TYPE is the desired type
2990 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2991 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2992 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2994 static struct z_candidate
*
2995 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
2996 tree ctype
, tree explicit_targs
, tree first_arg
,
2997 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
2998 tree access_path
, tree conversion_path
,
2999 int flags
, tree obj
, unification_kind_t strict
,
3000 tsubst_flags_t complain
)
3002 int ntparms
= DECL_NTPARMS (tmpl
);
3003 tree targs
= make_tree_vec (ntparms
);
3004 unsigned int len
= vec_safe_length (arglist
);
3005 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3006 unsigned int skip_without_in_chrg
= 0;
3007 tree first_arg_without_in_chrg
= first_arg
;
3008 tree
*args_without_in_chrg
;
3009 unsigned int nargs_without_in_chrg
;
3010 unsigned int ia
, ix
;
3012 struct z_candidate
*cand
;
3014 struct rejection_reason
*reason
= NULL
;
3017 /* We don't do deduction on the in-charge parameter, the VTT
3018 parameter or 'this'. */
3019 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3021 if (first_arg_without_in_chrg
!= NULL_TREE
)
3022 first_arg_without_in_chrg
= NULL_TREE
;
3024 ++skip_without_in_chrg
;
3027 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3028 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3029 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3031 if (first_arg_without_in_chrg
!= NULL_TREE
)
3032 first_arg_without_in_chrg
= NULL_TREE
;
3034 ++skip_without_in_chrg
;
3037 if (len
< skip_without_in_chrg
)
3040 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3041 + (len
- skip_without_in_chrg
));
3042 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3044 if (first_arg_without_in_chrg
!= NULL_TREE
)
3046 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3049 for (ix
= skip_without_in_chrg
;
3050 vec_safe_iterate (arglist
, ix
, &arg
);
3053 args_without_in_chrg
[ia
] = arg
;
3056 gcc_assert (ia
== nargs_without_in_chrg
);
3058 errs
= errorcount
+sorrycount
;
3059 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3060 args_without_in_chrg
,
3061 nargs_without_in_chrg
,
3062 return_type
, strict
, flags
, false,
3063 complain
& tf_decltype
);
3065 if (fn
== error_mark_node
)
3067 /* Don't repeat unification later if it already resulted in errors. */
3068 if (errorcount
+sorrycount
== errs
)
3069 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3070 targs
, args_without_in_chrg
,
3071 nargs_without_in_chrg
,
3072 return_type
, strict
, flags
);
3074 reason
= template_unification_error_rejection ();
3080 A member function template is never instantiated to perform the
3081 copy of a class object to an object of its class type.
3083 It's a little unclear what this means; the standard explicitly
3084 does allow a template to be used to copy a class. For example,
3089 template <class T> A(const T&);
3092 void g () { A a (f ()); }
3094 the member template will be used to make the copy. The section
3095 quoted above appears in the paragraph that forbids constructors
3096 whose only parameter is (a possibly cv-qualified variant of) the
3097 class type, and a logical interpretation is that the intent was
3098 to forbid the instantiation of member templates which would then
3100 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3102 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3103 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3106 reason
= invalid_copy_with_fn_template_rejection ();
3111 if (obj
!= NULL_TREE
)
3112 /* Aha, this is a conversion function. */
3113 cand
= add_conv_candidate (candidates
, fn
, obj
, first_arg
, arglist
,
3114 access_path
, conversion_path
, complain
);
3116 cand
= add_function_candidate (candidates
, fn
, ctype
,
3117 first_arg
, arglist
, access_path
,
3118 conversion_path
, flags
, complain
);
3119 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3120 /* This situation can occur if a member template of a template
3121 class is specialized. Then, instantiate_template might return
3122 an instantiation of the specialization, in which case the
3123 DECL_TI_TEMPLATE field will point at the original
3124 specialization. For example:
3126 template <class T> struct S { template <class U> void f(U);
3127 template <> void f(int) {}; };
3131 Here, TMPL will be template <class U> S<double>::f(U).
3132 And, instantiate template will give us the specialization
3133 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3134 for this will point at template <class T> template <> S<T>::f(int),
3135 so that we can find the definition. For the purposes of
3136 overload resolution, however, we want the original TMPL. */
3137 cand
->template_decl
= build_template_info (tmpl
, targs
);
3139 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3140 cand
->explicit_targs
= explicit_targs
;
3144 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3145 access_path
, conversion_path
, 0, reason
, flags
);
3149 static struct z_candidate
*
3150 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3151 tree explicit_targs
, tree first_arg
,
3152 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3153 tree access_path
, tree conversion_path
, int flags
,
3154 unification_kind_t strict
, tsubst_flags_t complain
)
3157 add_template_candidate_real (candidates
, tmpl
, ctype
,
3158 explicit_targs
, first_arg
, arglist
,
3159 return_type
, access_path
, conversion_path
,
3160 flags
, NULL_TREE
, strict
, complain
);
3164 static struct z_candidate
*
3165 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3166 tree obj
, tree first_arg
,
3167 const vec
<tree
, va_gc
> *arglist
,
3168 tree return_type
, tree access_path
,
3169 tree conversion_path
, tsubst_flags_t complain
)
3172 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3173 first_arg
, arglist
, return_type
, access_path
,
3174 conversion_path
, 0, obj
, DEDUCE_CONV
,
3178 /* The CANDS are the set of candidates that were considered for
3179 overload resolution. Return the set of viable candidates, or CANDS
3180 if none are viable. If any of the candidates were viable, set
3181 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3182 considered viable only if it is strictly viable. */
3184 static struct z_candidate
*
3185 splice_viable (struct z_candidate
*cands
,
3189 struct z_candidate
*viable
;
3190 struct z_candidate
**last_viable
;
3191 struct z_candidate
**cand
;
3192 bool found_strictly_viable
= false;
3194 /* Be strict inside templates, since build_over_call won't actually
3195 do the conversions to get pedwarns. */
3196 if (processing_template_decl
)
3200 last_viable
= &viable
;
3201 *any_viable_p
= false;
3206 struct z_candidate
*c
= *cand
;
3208 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3210 /* Be strict in the presence of a viable candidate. Also if
3211 there are template candidates, so that we get deduction errors
3212 for them instead of silently preferring a bad conversion. */
3214 if (viable
&& !found_strictly_viable
)
3216 /* Put any spliced near matches back onto the main list so
3217 that we see them if there is no strict match. */
3218 *any_viable_p
= false;
3219 *last_viable
= cands
;
3222 last_viable
= &viable
;
3226 if (strict_p
? c
->viable
== 1 : c
->viable
)
3231 last_viable
= &c
->next
;
3232 *any_viable_p
= true;
3234 found_strictly_viable
= true;
3240 return viable
? viable
: cands
;
3244 any_strictly_viable (struct z_candidate
*cands
)
3246 for (; cands
; cands
= cands
->next
)
3247 if (cands
->viable
== 1)
3252 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3253 words, it is about to become the "this" pointer for a member
3254 function call. Take the address of the object. */
3257 build_this (tree obj
)
3259 /* In a template, we are only concerned about the type of the
3260 expression, so we can take a shortcut. */
3261 if (processing_template_decl
)
3262 return build_address (obj
);
3264 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3267 /* Returns true iff functions are equivalent. Equivalent functions are
3268 not '==' only if one is a function-local extern function or if
3269 both are extern "C". */
3272 equal_functions (tree fn1
, tree fn2
)
3274 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3276 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3278 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3279 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3280 return decls_match (fn1
, fn2
);
3284 /* Print information about a candidate being rejected due to INFO. */
3287 print_conversion_rejection (location_t loc
, struct conversion_info
*info
)
3289 tree from
= info
->from
;
3291 from
= lvalue_type (from
);
3292 if (info
->n_arg
== -1)
3294 /* Conversion of implicit `this' argument failed. */
3295 if (!TYPE_P (info
->from
))
3296 /* A bad conversion for 'this' must be discarding cv-quals. */
3297 inform (loc
, " passing %qT as %<this%> "
3298 "argument discards qualifiers",
3301 inform (loc
, " no known conversion for implicit "
3302 "%<this%> parameter from %qT to %qT",
3303 from
, info
->to_type
);
3305 else if (!TYPE_P (info
->from
))
3307 if (info
->n_arg
>= 0)
3308 inform (loc
, " conversion of argument %d would be ill-formed:",
3310 perform_implicit_conversion (info
->to_type
, info
->from
,
3311 tf_warning_or_error
);
3313 else if (info
->n_arg
== -2)
3314 /* Conversion of conversion function return value failed. */
3315 inform (loc
, " no known conversion from %qT to %qT",
3316 from
, info
->to_type
);
3318 inform (loc
, " no known conversion for argument %d from %qT to %qT",
3319 info
->n_arg
+ 1, from
, info
->to_type
);
3322 /* Print information about a candidate with WANT parameters and we found
3326 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3328 inform_n (loc
, want
,
3329 " candidate expects %d argument, %d provided",
3330 " candidate expects %d arguments, %d provided",
3334 /* Print information about one overload candidate CANDIDATE. MSGSTR
3335 is the text to print before the candidate itself.
3337 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3338 to have been run through gettext by the caller. This wart makes
3339 life simpler in print_z_candidates and for the translators. */
3342 print_z_candidate (location_t loc
, const char *msgstr
,
3343 struct z_candidate
*candidate
)
3345 const char *msg
= (msgstr
== NULL
3347 : ACONCAT ((msgstr
, " ", NULL
)));
3348 location_t cloc
= location_of (candidate
->fn
);
3350 if (identifier_p (candidate
->fn
))
3353 if (candidate
->num_convs
== 3)
3354 inform (cloc
, "%s%D(%T, %T, %T) <built-in>", msg
, candidate
->fn
,
3355 candidate
->convs
[0]->type
,
3356 candidate
->convs
[1]->type
,
3357 candidate
->convs
[2]->type
);
3358 else if (candidate
->num_convs
== 2)
3359 inform (cloc
, "%s%D(%T, %T) <built-in>", msg
, candidate
->fn
,
3360 candidate
->convs
[0]->type
,
3361 candidate
->convs
[1]->type
);
3363 inform (cloc
, "%s%D(%T) <built-in>", msg
, candidate
->fn
,
3364 candidate
->convs
[0]->type
);
3366 else if (TYPE_P (candidate
->fn
))
3367 inform (cloc
, "%s%T <conversion>", msg
, candidate
->fn
);
3368 else if (candidate
->viable
== -1)
3369 inform (cloc
, "%s%#D <near match>", msg
, candidate
->fn
);
3370 else if (DECL_DELETED_FN (candidate
->fn
))
3371 inform (cloc
, "%s%#D <deleted>", msg
, candidate
->fn
);
3373 inform (cloc
, "%s%#D", msg
, candidate
->fn
);
3374 /* Give the user some information about why this candidate failed. */
3375 if (candidate
->reason
!= NULL
)
3377 struct rejection_reason
*r
= candidate
->reason
;
3382 print_arity_information (cloc
, r
->u
.arity
.actual
,
3383 r
->u
.arity
.expected
);
3385 case rr_arg_conversion
:
3386 print_conversion_rejection (cloc
, &r
->u
.conversion
);
3388 case rr_bad_arg_conversion
:
3389 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
);
3391 case rr_explicit_conversion
:
3392 inform (cloc
, " return type %qT of explicit conversion function "
3393 "cannot be converted to %qT with a qualification "
3394 "conversion", r
->u
.conversion
.from
,
3395 r
->u
.conversion
.to_type
);
3397 case rr_template_conversion
:
3398 inform (cloc
, " conversion from return type %qT of template "
3399 "conversion function specialization to %qT is not an "
3400 "exact match", r
->u
.conversion
.from
,
3401 r
->u
.conversion
.to_type
);
3403 case rr_template_unification
:
3404 /* We use template_unification_error_rejection if unification caused
3405 actual non-SFINAE errors, in which case we don't need to repeat
3407 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3409 inform (cloc
, " substitution of deduced template arguments "
3410 "resulted in errors seen above");
3413 /* Re-run template unification with diagnostics. */
3414 inform (cloc
, " template argument deduction/substitution failed:");
3415 fn_type_unification (r
->u
.template_unification
.tmpl
,
3416 r
->u
.template_unification
.explicit_targs
,
3418 (r
->u
.template_unification
.num_targs
)),
3419 r
->u
.template_unification
.args
,
3420 r
->u
.template_unification
.nargs
,
3421 r
->u
.template_unification
.return_type
,
3422 r
->u
.template_unification
.strict
,
3423 r
->u
.template_unification
.flags
,
3426 case rr_invalid_copy
:
3428 " a constructor taking a single argument of its own "
3429 "class type is invalid");
3431 case rr_constraint_failure
:
3433 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3434 tree args
= r
->u
.template_instantiation
.targs
;
3435 diagnose_constraints (cloc
, tmpl
, args
);
3440 /* This candidate didn't have any issues or we failed to
3441 handle a particular code. Either way... */
3448 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3450 struct z_candidate
*cand1
;
3451 struct z_candidate
**cand2
;
3456 /* Remove non-viable deleted candidates. */
3458 for (cand2
= &cand1
; *cand2
; )
3460 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3461 && !(*cand2
)->viable
3462 && DECL_DELETED_FN ((*cand2
)->fn
))
3463 *cand2
= (*cand2
)->next
;
3465 cand2
= &(*cand2
)->next
;
3467 /* ...if there are any non-deleted ones. */
3471 /* There may be duplicates in the set of candidates. We put off
3472 checking this condition as long as possible, since we have no way
3473 to eliminate duplicates from a set of functions in less than n^2
3474 time. Now we are about to emit an error message, so it is more
3475 permissible to go slowly. */
3476 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3478 tree fn
= cand1
->fn
;
3479 /* Skip builtin candidates and conversion functions. */
3482 cand2
= &cand1
->next
;
3485 if (DECL_P ((*cand2
)->fn
)
3486 && equal_functions (fn
, (*cand2
)->fn
))
3487 *cand2
= (*cand2
)->next
;
3489 cand2
= &(*cand2
)->next
;
3493 for (; candidates
; candidates
= candidates
->next
)
3494 print_z_candidate (loc
, "candidate:", candidates
);
3497 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3498 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3499 the result of the conversion function to convert it to the final
3500 desired type. Merge the two sequences into a single sequence,
3501 and return the merged sequence. */
3504 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3507 bool bad
= user_seq
->bad_p
;
3509 gcc_assert (user_seq
->kind
== ck_user
);
3511 /* Find the end of the second conversion sequence. */
3512 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3514 /* The entire sequence is a user-conversion sequence. */
3515 (*t
)->user_conv_p
= true;
3520 /* Replace the identity conversion with the user conversion
3527 /* Handle overload resolution for initializing an object of class type from
3528 an initializer list. First we look for a suitable constructor that
3529 takes a std::initializer_list; if we don't find one, we then look for a
3530 non-list constructor.
3532 Parameters are as for add_candidates, except that the arguments are in
3533 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3534 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3537 add_list_candidates (tree fns
, tree first_arg
,
3538 tree init_list
, tree totype
,
3539 tree explicit_targs
, bool template_only
,
3540 tree conversion_path
, tree access_path
,
3542 struct z_candidate
**candidates
,
3543 tsubst_flags_t complain
)
3545 vec
<tree
, va_gc
> *args
;
3547 gcc_assert (*candidates
== NULL
);
3549 /* We're looking for a ctor for list-initialization. */
3550 flags
|= LOOKUP_LIST_INIT_CTOR
;
3551 /* And we don't allow narrowing conversions. We also use this flag to
3552 avoid the copy constructor call for copy-list-initialization. */
3553 flags
|= LOOKUP_NO_NARROWING
;
3555 /* Always use the default constructor if the list is empty (DR 990). */
3556 if (CONSTRUCTOR_NELTS (init_list
) == 0
3557 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3559 /* If the class has a list ctor, try passing the list as a single
3560 argument first, but only consider list ctors. */
3561 else if (TYPE_HAS_LIST_CTOR (totype
))
3563 flags
|= LOOKUP_LIST_ONLY
;
3564 args
= make_tree_vector_single (init_list
);
3565 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3566 explicit_targs
, template_only
, conversion_path
,
3567 access_path
, flags
, candidates
, complain
);
3568 if (any_strictly_viable (*candidates
))
3572 args
= ctor_to_vec (init_list
);
3574 /* We aren't looking for list-ctors anymore. */
3575 flags
&= ~LOOKUP_LIST_ONLY
;
3576 /* We allow more user-defined conversions within an init-list. */
3577 flags
&= ~LOOKUP_NO_CONVERSION
;
3579 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3580 explicit_targs
, template_only
, conversion_path
,
3581 access_path
, flags
, candidates
, complain
);
3584 /* Returns the best overload candidate to perform the requested
3585 conversion. This function is used for three the overloading situations
3586 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3587 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3588 per [dcl.init.ref], so we ignore temporary bindings. */
3590 static struct z_candidate
*
3591 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3592 tsubst_flags_t complain
)
3594 struct z_candidate
*candidates
, *cand
;
3596 tree ctors
= NULL_TREE
;
3597 tree conv_fns
= NULL_TREE
;
3598 conversion
*conv
= NULL
;
3599 tree first_arg
= NULL_TREE
;
3600 vec
<tree
, va_gc
> *args
= NULL
;
3607 fromtype
= TREE_TYPE (expr
);
3609 /* We represent conversion within a hierarchy using RVALUE_CONV and
3610 BASE_CONV, as specified by [over.best.ics]; these become plain
3611 constructor calls, as specified in [dcl.init]. */
3612 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3613 || !DERIVED_FROM_P (totype
, fromtype
));
3615 if (MAYBE_CLASS_TYPE_P (totype
))
3616 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3617 creating a garbage BASELINK; constructors can't be inherited. */
3618 ctors
= lookup_fnfields_slot (totype
, complete_ctor_identifier
);
3620 if (MAYBE_CLASS_TYPE_P (fromtype
))
3622 tree to_nonref
= non_reference (totype
);
3623 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3624 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3625 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3627 /* [class.conv.fct] A conversion function is never used to
3628 convert a (possibly cv-qualified) object to the (possibly
3629 cv-qualified) same object type (or a reference to it), to a
3630 (possibly cv-qualified) base class of that type (or a
3631 reference to it)... */
3634 conv_fns
= lookup_conversions (fromtype
);
3638 flags
|= LOOKUP_NO_CONVERSION
;
3639 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3640 flags
|= LOOKUP_NO_NARROWING
;
3642 /* It's OK to bind a temporary for converting constructor arguments, but
3643 not in converting the return value of a conversion operator. */
3644 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3645 | (flags
& LOOKUP_NO_NARROWING
));
3646 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3650 int ctorflags
= flags
;
3652 first_arg
= build_dummy_object (totype
);
3654 /* We should never try to call the abstract or base constructor
3656 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors
))
3657 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors
)));
3659 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3661 /* List-initialization. */
3662 add_list_candidates (ctors
, first_arg
, expr
, totype
, NULL_TREE
,
3663 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3664 ctorflags
, &candidates
, complain
);
3668 args
= make_tree_vector_single (expr
);
3669 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3670 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3671 ctorflags
, &candidates
, complain
);
3674 for (cand
= candidates
; cand
; cand
= cand
->next
)
3676 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3678 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3679 set, then this is copy-initialization. In that case, "The
3680 result of the call is then used to direct-initialize the
3681 object that is the destination of the copy-initialization."
3684 We represent this in the conversion sequence with an
3685 rvalue conversion, which means a constructor call. */
3686 if (TREE_CODE (totype
) != REFERENCE_TYPE
3687 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3689 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3696 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3698 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3699 struct z_candidate
*old_candidates
;
3701 /* If we are called to convert to a reference type, we are trying to
3702 find a direct binding, so don't even consider temporaries. If
3703 we don't find a direct binding, the caller will try again to
3704 look for a temporary binding. */
3705 if (TREE_CODE (totype
) == REFERENCE_TYPE
)
3706 convflags
|= LOOKUP_NO_TEMP_BIND
;
3708 old_candidates
= candidates
;
3709 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3711 conversion_path
, TYPE_BINFO (fromtype
),
3712 flags
, &candidates
, complain
);
3714 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
3716 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
3718 = implicit_conversion (totype
,
3721 /*c_cast_p=*/false, convflags
,
3724 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3725 copy-initialization. In that case, "The result of the
3726 call is then used to direct-initialize the object that is
3727 the destination of the copy-initialization." [dcl.init]
3729 We represent this in the conversion sequence with an
3730 rvalue conversion, which means a constructor call. But
3731 don't add a second rvalue conversion if there's already
3732 one there. Which there really shouldn't be, but it's
3733 harmless since we'd add it here anyway. */
3734 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
3735 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3736 ics
= build_conv (ck_rvalue
, totype
, ics
);
3738 cand
->second_conv
= ics
;
3743 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
3746 else if (DECL_NONCONVERTING_P (cand
->fn
)
3747 && ics
->rank
> cr_exact
)
3749 /* 13.3.1.5: For direct-initialization, those explicit
3750 conversion functions that are not hidden within S and
3751 yield type T or a type that can be converted to type T
3752 with a qualification conversion (4.4) are also candidate
3754 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3755 I've raised this issue with the committee. --jason 9/2011 */
3757 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
3759 else if (cand
->viable
== 1 && ics
->bad_p
)
3763 = bad_arg_conversion_rejection (NULL_TREE
, -2,
3766 else if (primary_template_instantiation_p (cand
->fn
)
3767 && ics
->rank
> cr_exact
)
3769 /* 13.3.3.1.2: If the user-defined conversion is specified by
3770 a specialization of a conversion function template, the
3771 second standard conversion sequence shall have exact match
3774 cand
->reason
= template_conversion_rejection (rettype
, totype
);
3779 candidates
= splice_viable (candidates
, false, &any_viable_p
);
3783 release_tree_vector (args
);
3787 cand
= tourney (candidates
, complain
);
3790 if (complain
& tf_error
)
3792 error ("conversion from %qT to %qT is ambiguous",
3794 print_z_candidates (location_of (expr
), candidates
);
3797 cand
= candidates
; /* any one will do */
3798 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
3799 cand
->second_conv
->user_conv_p
= true;
3800 if (!any_strictly_viable (candidates
))
3801 cand
->second_conv
->bad_p
= true;
3802 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3803 ambiguous conversion is no worse than another user-defined
3810 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
3811 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
3812 else if (cand
->second_conv
->kind
== ck_rvalue
)
3813 /* DR 5: [in the first step of copy-initialization]...if the function
3814 is a constructor, the call initializes a temporary of the
3815 cv-unqualified version of the destination type. */
3816 convtype
= cv_unqualified (totype
);
3819 /* Build the user conversion sequence. */
3823 build_identity_conv (TREE_TYPE (expr
), expr
));
3825 if (cand
->viable
== -1)
3828 /* Remember that this was a list-initialization. */
3829 if (flags
& LOOKUP_NO_NARROWING
)
3830 conv
->check_narrowing
= true;
3832 /* Combine it with the second conversion sequence. */
3833 cand
->second_conv
= merge_conversion_sequences (conv
,
3839 /* Wrapper for above. */
3842 build_user_type_conversion (tree totype
, tree expr
, int flags
,
3843 tsubst_flags_t complain
)
3845 struct z_candidate
*cand
;
3848 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
3849 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
3853 if (cand
->second_conv
->kind
== ck_ambig
)
3854 ret
= error_mark_node
;
3857 expr
= convert_like (cand
->second_conv
, expr
, complain
);
3858 ret
= convert_from_reference (expr
);
3864 timevar_cond_stop (TV_OVERLOAD
, subtime
);
3868 /* Subroutine of convert_nontype_argument.
3870 EXPR is an argument for a template non-type parameter of integral or
3871 enumeration type. Do any necessary conversions (that are permitted for
3872 non-type arguments) to convert it to the parameter type.
3874 If conversion is successful, returns the converted expression;
3875 otherwise, returns error_mark_node. */
3878 build_integral_nontype_arg_conv (tree type
, tree expr
, tsubst_flags_t complain
)
3883 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
3885 if (error_operand_p (expr
))
3886 return error_mark_node
;
3888 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type
));
3890 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3891 p
= conversion_obstack_alloc (0);
3893 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
3895 LOOKUP_IMPLICIT
, complain
);
3897 /* for a non-type template-parameter of integral or
3898 enumeration type, integral promotions (4.5) and integral
3899 conversions (4.7) are applied. */
3900 /* It should be sufficient to check the outermost conversion step, since
3901 there are no qualification conversions to integer type. */
3905 /* A conversion function is OK. If it isn't constexpr, we'll
3906 complain later that the argument isn't constant. */
3908 /* The lvalue-to-rvalue conversion is OK. */
3914 t
= next_conversion (conv
)->type
;
3915 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
))
3918 if (complain
& tf_error
)
3919 error_at (loc
, "conversion from %qT to %qT not considered for "
3920 "non-type template argument", t
, type
);
3921 /* and fall through. */
3929 expr
= convert_like (conv
, expr
, complain
);
3931 expr
= error_mark_node
;
3933 /* Free all the conversions we allocated. */
3934 obstack_free (&conversion_obstack
, p
);
3939 /* Do any initial processing on the arguments to a function call. */
3941 static vec
<tree
, va_gc
> *
3942 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
3947 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
3949 if (error_operand_p (arg
))
3951 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
3953 if (complain
& tf_error
)
3954 error ("invalid use of void expression");
3957 else if (invalid_nonstatic_memfn_p (input_location
, arg
, complain
))
3963 /* Perform overload resolution on FN, which is called with the ARGS.
3965 Return the candidate function selected by overload resolution, or
3966 NULL if the event that overload resolution failed. In the case
3967 that overload resolution fails, *CANDIDATES will be the set of
3968 candidates considered, and ANY_VIABLE_P will be set to true or
3969 false to indicate whether or not any of the candidates were
3972 The ARGS should already have gone through RESOLVE_ARGS before this
3973 function is called. */
3975 static struct z_candidate
*
3976 perform_overload_resolution (tree fn
,
3977 const vec
<tree
, va_gc
> *args
,
3978 struct z_candidate
**candidates
,
3979 bool *any_viable_p
, tsubst_flags_t complain
)
3981 struct z_candidate
*cand
;
3982 tree explicit_targs
;
3985 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
3987 explicit_targs
= NULL_TREE
;
3991 *any_viable_p
= true;
3994 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
3995 || TREE_CODE (fn
) == TEMPLATE_DECL
3996 || TREE_CODE (fn
) == OVERLOAD
3997 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
3999 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4001 explicit_targs
= TREE_OPERAND (fn
, 1);
4002 fn
= TREE_OPERAND (fn
, 0);
4006 /* Add the various candidate functions. */
4007 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4008 explicit_targs
, template_only
,
4009 /*conversion_path=*/NULL_TREE
,
4010 /*access_path=*/NULL_TREE
,
4012 candidates
, complain
);
4014 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4016 cand
= tourney (*candidates
, complain
);
4020 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4024 /* Print an error message about being unable to build a call to FN with
4025 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4026 be located; CANDIDATES is a possibly empty list of such
4030 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4031 struct z_candidate
*candidates
)
4033 tree name
= DECL_NAME (OVL_CURRENT (fn
));
4034 location_t loc
= location_of (name
);
4036 if (!any_strictly_viable (candidates
))
4037 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4038 name
, build_tree_list_vec (args
));
4040 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4041 name
, build_tree_list_vec (args
));
4043 print_z_candidates (loc
, candidates
);
4046 /* Return an expression for a call to FN (a namespace-scope function,
4047 or a static member function) with the ARGS. This may change
4051 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
, bool koenig_p
,
4052 tsubst_flags_t complain
)
4054 struct z_candidate
*candidates
, *cand
;
4059 if (args
!= NULL
&& *args
!= NULL
)
4061 *args
= resolve_args (*args
, complain
);
4063 return error_mark_node
;
4067 tm_malloc_replacement (fn
);
4069 /* If this function was found without using argument dependent
4070 lookup, then we want to ignore any undeclared friend
4076 fn
= remove_hidden_names (fn
);
4079 if (complain
& tf_error
)
4080 print_error_for_call_failure (orig_fn
, *args
, NULL
);
4081 return error_mark_node
;
4085 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4086 p
= conversion_obstack_alloc (0);
4088 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4093 if (complain
& tf_error
)
4095 // If there is a single (non-viable) function candidate,
4096 // let the error be diagnosed by cp_build_function_call_vec.
4097 if (!any_viable_p
&& candidates
&& ! candidates
->next
4098 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4099 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4101 // Otherwise, emit notes for non-viable candidates.
4102 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4103 fn
= TREE_OPERAND (fn
, 0);
4104 print_error_for_call_failure (fn
, *args
, candidates
);
4106 result
= error_mark_node
;
4110 int flags
= LOOKUP_NORMAL
;
4111 /* If fn is template_id_expr, the call has explicit template arguments
4112 (e.g. func<int>(5)), communicate this info to build_over_call
4113 through flags so that later we can use it to decide whether to warn
4114 about peculiar null pointer conversion. */
4115 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4117 /* If overload resolution selects a specialization of a
4118 function concept for non-dependent template arguments,
4119 the expression is true if the constraints are satisfied
4120 and false otherwise.
4122 NOTE: This is an extension of Concepts Lite TS that
4123 allows constraints to be used in expressions. */
4124 if (flag_concepts
&& !processing_template_decl
)
4126 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4127 tree targs
= DECL_TI_ARGS (cand
->fn
);
4128 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4129 if (DECL_DECLARED_CONCEPT_P (decl
))
4130 return evaluate_function_concept (decl
, targs
);
4133 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4136 result
= build_over_call (cand
, flags
, complain
);
4139 /* Free all the conversions we allocated. */
4140 obstack_free (&conversion_obstack
, p
);
4145 /* Build a call to a global operator new. FNNAME is the name of the
4146 operator (either "operator new" or "operator new[]") and ARGS are
4147 the arguments provided. This may change ARGS. *SIZE points to the
4148 total number of bytes required by the allocation, and is updated if
4149 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4150 be used. If this function determines that no cookie should be
4151 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4152 is not NULL_TREE, it is evaluated before calculating the final
4153 array size, and if it fails, the array size is replaced with
4154 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4155 is non-NULL, it will be set, upon return, to the allocation
4159 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4160 tree
*size
, tree
*cookie_size
, tree size_check
,
4161 tree
*fn
, tsubst_flags_t complain
)
4163 tree original_size
= *size
;
4165 struct z_candidate
*candidates
;
4166 struct z_candidate
*cand
;
4171 /* Set to (size_t)-1 if the size check fails. */
4172 if (size_check
!= NULL_TREE
)
4174 tree errval
= TYPE_MAX_VALUE (sizetype
);
4175 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4176 errval
= throw_bad_array_new_length ();
4177 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4178 original_size
, errval
);
4180 vec_safe_insert (*args
, 0, *size
);
4181 *args
= resolve_args (*args
, complain
);
4183 return error_mark_node
;
4189 If this lookup fails to find the name, or if the allocated type
4190 is not a class type, the allocation function's name is looked
4191 up in the global scope.
4193 we disregard block-scope declarations of "operator new". */
4194 fns
= lookup_function_nonclass (fnname
, *args
, /*block_p=*/false);
4196 /* Figure out what function is being called. */
4197 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4200 /* If no suitable function could be found, issue an error message
4204 if (complain
& tf_error
)
4205 print_error_for_call_failure (fns
, *args
, candidates
);
4206 return error_mark_node
;
4209 /* If a cookie is required, add some extra space. Whether
4210 or not a cookie is required cannot be determined until
4211 after we know which function was called. */
4214 bool use_cookie
= true;
4217 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4218 /* Skip the size_t parameter. */
4219 arg_types
= TREE_CHAIN (arg_types
);
4220 /* Check the remaining parameters (if any). */
4222 && TREE_CHAIN (arg_types
) == void_list_node
4223 && same_type_p (TREE_VALUE (arg_types
),
4226 /* If we need a cookie, adjust the number of bytes allocated. */
4229 /* Update the total size. */
4230 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4231 /* Set to (size_t)-1 if the size check fails. */
4232 gcc_assert (size_check
!= NULL_TREE
);
4233 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4234 *size
, TYPE_MAX_VALUE (sizetype
));
4235 /* Update the argument list to reflect the adjusted size. */
4236 (**args
)[0] = *size
;
4239 *cookie_size
= NULL_TREE
;
4242 /* Tell our caller which function we decided to call. */
4246 /* Build the CALL_EXPR. */
4247 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4250 /* Build a new call to operator(). This may change ARGS. */
4253 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4255 struct z_candidate
*candidates
= 0, *cand
;
4256 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4257 tree type
= TREE_TYPE (obj
);
4259 tree result
= NULL_TREE
;
4262 if (error_operand_p (obj
))
4263 return error_mark_node
;
4265 obj
= prep_operand (obj
);
4267 if (TYPE_PTRMEMFUNC_P (type
))
4269 if (complain
& tf_error
)
4270 /* It's no good looking for an overloaded operator() on a
4271 pointer-to-member-function. */
4272 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj
);
4273 return error_mark_node
;
4276 if (TYPE_BINFO (type
))
4278 fns
= lookup_fnfields (TYPE_BINFO (type
), ansi_opname (CALL_EXPR
), 1);
4279 if (fns
== error_mark_node
)
4280 return error_mark_node
;
4285 if (args
!= NULL
&& *args
!= NULL
)
4287 *args
= resolve_args (*args
, complain
);
4289 return error_mark_node
;
4292 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4293 p
= conversion_obstack_alloc (0);
4297 first_mem_arg
= obj
;
4299 add_candidates (BASELINK_FUNCTIONS (fns
),
4300 first_mem_arg
, *args
, NULL_TREE
,
4302 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4303 LOOKUP_NORMAL
, &candidates
, complain
);
4306 convs
= lookup_conversions (type
);
4308 for (; convs
; convs
= TREE_CHAIN (convs
))
4310 tree fns
= TREE_VALUE (convs
);
4311 tree totype
= TREE_TYPE (convs
);
4313 if (TYPE_PTRFN_P (totype
)
4314 || TYPE_REFFN_P (totype
)
4315 || (TREE_CODE (totype
) == REFERENCE_TYPE
4316 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4317 for (; fns
; fns
= OVL_NEXT (fns
))
4319 tree fn
= OVL_CURRENT (fns
);
4321 if (DECL_NONCONVERTING_P (fn
))
4324 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4325 add_template_conv_candidate
4326 (&candidates
, fn
, obj
, NULL_TREE
, *args
, totype
,
4327 /*access_path=*/NULL_TREE
,
4328 /*conversion_path=*/NULL_TREE
, complain
);
4330 add_conv_candidate (&candidates
, fn
, obj
, NULL_TREE
,
4331 *args
, /*conversion_path=*/NULL_TREE
,
4332 /*access_path=*/NULL_TREE
, complain
);
4336 /* Be strict here because if we choose a bad conversion candidate, the
4337 errors we get won't mention the call context. */
4338 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4341 if (complain
& tf_error
)
4343 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4344 build_tree_list_vec (*args
));
4345 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4347 result
= error_mark_node
;
4351 cand
= tourney (candidates
, complain
);
4354 if (complain
& tf_error
)
4356 error ("call of %<(%T) (%A)%> is ambiguous",
4357 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4358 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4360 result
= error_mark_node
;
4362 /* Since cand->fn will be a type, not a function, for a conversion
4363 function, we must be careful not to unconditionally look at
4365 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4366 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
) == CALL_EXPR
)
4367 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4370 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
, -1,
4372 obj
= convert_from_reference (obj
);
4373 result
= cp_build_function_call_vec (obj
, args
, complain
);
4377 /* Free all the conversions we allocated. */
4378 obstack_free (&conversion_obstack
, p
);
4383 /* Wrapper for above. */
4386 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4389 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4390 ret
= build_op_call_1 (obj
, args
, complain
);
4391 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4395 /* Called by op_error to prepare format strings suitable for the error
4396 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4397 and a suffix (controlled by NTYPES). */
4400 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4404 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4405 : G_("no match for "), errmsg
, NULL
);
4408 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4409 else if (ntypes
== 2)
4410 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4412 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4418 op_error (location_t loc
, enum tree_code code
, enum tree_code code2
,
4419 tree arg1
, tree arg2
, tree arg3
, bool match
)
4423 if (code
== MODIFY_EXPR
)
4424 opname
= assignment_operator_name_info
[code2
].name
;
4426 opname
= operator_name_info
[code
].name
;
4431 if (flag_diagnostics_show_caret
)
4432 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4434 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4436 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4437 "in %<%E ? %E : %E%>"), 3, match
),
4439 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4442 case POSTINCREMENT_EXPR
:
4443 case POSTDECREMENT_EXPR
:
4444 if (flag_diagnostics_show_caret
)
4445 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4446 opname
, TREE_TYPE (arg1
));
4448 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4450 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4454 if (flag_diagnostics_show_caret
)
4455 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4456 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4458 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4460 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4465 if (flag_diagnostics_show_caret
)
4466 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4467 opname
, TREE_TYPE (arg1
));
4469 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4470 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4475 if (flag_diagnostics_show_caret
)
4476 error_at (loc
, op_error_string (G_("%<operator%s%>"), 2, match
),
4477 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4479 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4481 opname
, arg1
, opname
, arg2
,
4482 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4484 if (flag_diagnostics_show_caret
)
4485 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4486 opname
, TREE_TYPE (arg1
));
4488 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4490 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4495 /* Return the implicit conversion sequence that could be used to
4496 convert E1 to E2 in [expr.cond]. */
4499 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4501 tree t1
= non_reference (TREE_TYPE (e1
));
4502 tree t2
= non_reference (TREE_TYPE (e2
));
4508 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4509 implicitly converted (clause _conv_) to the type "lvalue reference to
4510 T2", subject to the constraint that in the conversion the
4511 reference must bind directly (_dcl.init.ref_) to an lvalue.
4513 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4514 implicitly converted to the type "rvalue reference to T2", subject to
4515 the constraint that the reference must bind directly. */
4516 if (lvalue_or_rvalue_with_address_p (e2
))
4518 tree rtype
= cp_build_reference_type (t2
, !real_lvalue_p (e2
));
4519 conv
= implicit_conversion (rtype
,
4523 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4524 |LOOKUP_ONLYCONVERTING
,
4526 if (conv
&& !conv
->bad_p
)
4530 /* If E2 is a prvalue or if neither of the conversions above can be done
4531 and at least one of the operands has (possibly cv-qualified) class
4533 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4538 If E1 and E2 have class type, and the underlying class types are
4539 the same or one is a base class of the other: E1 can be converted
4540 to match E2 if the class of T2 is the same type as, or a base
4541 class of, the class of T1, and the cv-qualification of T2 is the
4542 same cv-qualification as, or a greater cv-qualification than, the
4543 cv-qualification of T1. If the conversion is applied, E1 is
4544 changed to an rvalue of type T2 that still refers to the original
4545 source class object (or the appropriate subobject thereof). */
4546 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4547 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4549 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4551 conv
= build_identity_conv (t1
, e1
);
4552 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4553 TYPE_MAIN_VARIANT (t2
)))
4554 conv
= build_conv (ck_base
, t2
, conv
);
4556 conv
= build_conv (ck_rvalue
, t2
, conv
);
4565 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4566 converted to the type that expression E2 would have if E2 were
4567 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4568 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4569 LOOKUP_IMPLICIT
, complain
);
4572 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4573 arguments to the conditional expression. */
4576 build_conditional_expr_1 (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
4577 tsubst_flags_t complain
)
4581 tree result
= NULL_TREE
;
4582 tree result_type
= NULL_TREE
;
4583 bool lvalue_p
= true;
4584 struct z_candidate
*candidates
= 0;
4585 struct z_candidate
*cand
;
4587 tree orig_arg2
, orig_arg3
;
4589 /* As a G++ extension, the second argument to the conditional can be
4590 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4591 c'.) If the second operand is omitted, make sure it is
4592 calculated only once. */
4595 if (complain
& tf_error
)
4596 pedwarn (loc
, OPT_Wpedantic
,
4597 "ISO C++ forbids omitting the middle term of a ?: expression");
4599 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4600 if (real_lvalue_p (arg1
))
4601 arg2
= arg1
= stabilize_reference (arg1
);
4603 arg2
= arg1
= save_expr (arg1
);
4606 /* If something has already gone wrong, just pass that fact up the
4608 if (error_operand_p (arg1
)
4609 || error_operand_p (arg2
)
4610 || error_operand_p (arg3
))
4611 return error_mark_node
;
4616 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
4618 arg1
= force_rvalue (arg1
, complain
);
4619 arg2
= force_rvalue (arg2
, complain
);
4620 arg3
= force_rvalue (arg3
, complain
);
4622 /* force_rvalue can return error_mark on valid arguments. */
4623 if (error_operand_p (arg1
)
4624 || error_operand_p (arg2
)
4625 || error_operand_p (arg3
))
4626 return error_mark_node
;
4628 tree arg1_type
= TREE_TYPE (arg1
);
4629 arg2_type
= TREE_TYPE (arg2
);
4630 arg3_type
= TREE_TYPE (arg3
);
4632 if (!VECTOR_TYPE_P (arg2_type
)
4633 && !VECTOR_TYPE_P (arg3_type
))
4635 /* Rely on the error messages of the scalar version. */
4636 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
4637 orig_arg2
, orig_arg3
, complain
);
4638 if (scal
== error_mark_node
)
4639 return error_mark_node
;
4640 tree stype
= TREE_TYPE (scal
);
4641 tree ctype
= TREE_TYPE (arg1_type
);
4642 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
4643 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
4645 if (complain
& tf_error
)
4646 error_at (loc
, "inferred scalar type %qT is not an integer or "
4647 "floating point type of the same size as %qT", stype
,
4648 COMPARISON_CLASS_P (arg1
)
4649 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
4651 return error_mark_node
;
4654 tree vtype
= build_opaque_vector_type (stype
,
4655 TYPE_VECTOR_SUBPARTS (arg1_type
));
4656 /* We could pass complain & tf_warning to unsafe_conversion_p,
4657 but the warnings (like Wsign-conversion) have already been
4658 given by the scalar build_conditional_expr_1. We still check
4659 unsafe_conversion_p to forbid truncating long long -> float. */
4660 if (unsafe_conversion_p (loc
, stype
, arg2
, false))
4662 if (complain
& tf_error
)
4663 error_at (loc
, "conversion of scalar %qT to vector %qT "
4664 "involves truncation", arg2_type
, vtype
);
4665 return error_mark_node
;
4667 if (unsafe_conversion_p (loc
, stype
, arg3
, false))
4669 if (complain
& tf_error
)
4670 error_at (loc
, "conversion of scalar %qT to vector %qT "
4671 "involves truncation", arg3_type
, vtype
);
4672 return error_mark_node
;
4675 arg2
= cp_convert (stype
, arg2
, complain
);
4676 arg2
= save_expr (arg2
);
4677 arg2
= build_vector_from_val (vtype
, arg2
);
4679 arg3
= cp_convert (stype
, arg3
, complain
);
4680 arg3
= save_expr (arg3
);
4681 arg3
= build_vector_from_val (vtype
, arg3
);
4685 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
4687 enum stv_conv convert_flag
=
4688 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
4689 complain
& tf_error
);
4691 switch (convert_flag
)
4694 return error_mark_node
;
4697 arg2
= save_expr (arg2
);
4698 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
4699 arg2
= build_vector_from_val (arg3_type
, arg2
);
4700 arg2_type
= TREE_TYPE (arg2
);
4705 arg3
= save_expr (arg3
);
4706 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
4707 arg3
= build_vector_from_val (arg2_type
, arg3
);
4708 arg3_type
= TREE_TYPE (arg3
);
4716 if (!same_type_p (arg2_type
, arg3_type
)
4717 || TYPE_VECTOR_SUBPARTS (arg1_type
)
4718 != TYPE_VECTOR_SUBPARTS (arg2_type
)
4719 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
4721 if (complain
& tf_error
)
4723 "incompatible vector types in conditional expression: "
4724 "%qT, %qT and %qT", TREE_TYPE (arg1
),
4725 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
4726 return error_mark_node
;
4729 if (!COMPARISON_CLASS_P (arg1
))
4730 arg1
= cp_build_binary_op (loc
, NE_EXPR
, arg1
,
4731 build_zero_cst (arg1_type
), complain
);
4732 return fold_build3 (VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
4737 The first expression is implicitly converted to bool (clause
4739 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
4741 if (error_operand_p (arg1
))
4742 return error_mark_node
;
4746 If either the second or the third operand has type (possibly
4747 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4748 array-to-pointer (_conv.array_), and function-to-pointer
4749 (_conv.func_) standard conversions are performed on the second
4750 and third operands. */
4751 arg2_type
= unlowered_expr_type (arg2
);
4752 arg3_type
= unlowered_expr_type (arg3
);
4753 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
4755 /* Do the conversions. We don't these for `void' type arguments
4756 since it can't have any effect and since decay_conversion
4757 does not handle that case gracefully. */
4758 if (!VOID_TYPE_P (arg2_type
))
4759 arg2
= decay_conversion (arg2
, complain
);
4760 if (!VOID_TYPE_P (arg3_type
))
4761 arg3
= decay_conversion (arg3
, complain
);
4762 arg2_type
= TREE_TYPE (arg2
);
4763 arg3_type
= TREE_TYPE (arg3
);
4767 One of the following shall hold:
4769 --The second or the third operand (but not both) is a
4770 throw-expression (_except.throw_); the result is of the
4771 type of the other and is an rvalue.
4773 --Both the second and the third operands have type void; the
4774 result is of type void and is an rvalue.
4776 We must avoid calling force_rvalue for expressions of type
4777 "void" because it will complain that their value is being
4779 if (TREE_CODE (arg2
) == THROW_EXPR
4780 && TREE_CODE (arg3
) != THROW_EXPR
)
4782 if (!VOID_TYPE_P (arg3_type
))
4784 arg3
= force_rvalue (arg3
, complain
);
4785 if (arg3
== error_mark_node
)
4786 return error_mark_node
;
4788 arg3_type
= TREE_TYPE (arg3
);
4789 result_type
= arg3_type
;
4791 else if (TREE_CODE (arg2
) != THROW_EXPR
4792 && TREE_CODE (arg3
) == THROW_EXPR
)
4794 if (!VOID_TYPE_P (arg2_type
))
4796 arg2
= force_rvalue (arg2
, complain
);
4797 if (arg2
== error_mark_node
)
4798 return error_mark_node
;
4800 arg2_type
= TREE_TYPE (arg2
);
4801 result_type
= arg2_type
;
4803 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
4804 result_type
= void_type_node
;
4807 if (complain
& tf_error
)
4809 if (VOID_TYPE_P (arg2_type
))
4810 error_at (EXPR_LOC_OR_LOC (arg3
, loc
),
4811 "second operand to the conditional operator "
4812 "is of type %<void%>, but the third operand is "
4813 "neither a throw-expression nor of type %<void%>");
4815 error_at (EXPR_LOC_OR_LOC (arg2
, loc
),
4816 "third operand to the conditional operator "
4817 "is of type %<void%>, but the second operand is "
4818 "neither a throw-expression nor of type %<void%>");
4820 return error_mark_node
;
4824 goto valid_operands
;
4828 Otherwise, if the second and third operand have different types,
4829 and either has (possibly cv-qualified) class type, or if both are
4830 glvalues of the same value category and the same type except for
4831 cv-qualification, an attempt is made to convert each of those operands
4832 to the type of the other. */
4833 else if (!same_type_p (arg2_type
, arg3_type
)
4834 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
4835 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
4837 && lvalue_or_rvalue_with_address_p (arg2
)
4838 && lvalue_or_rvalue_with_address_p (arg3
)
4839 && real_lvalue_p (arg2
) == real_lvalue_p (arg3
))))
4843 bool converted
= false;
4845 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4846 p
= conversion_obstack_alloc (0);
4848 conv2
= conditional_conversion (arg2
, arg3
, complain
);
4849 conv3
= conditional_conversion (arg3
, arg2
, complain
);
4853 If both can be converted, or one can be converted but the
4854 conversion is ambiguous, the program is ill-formed. If
4855 neither can be converted, the operands are left unchanged and
4856 further checking is performed as described below. If exactly
4857 one conversion is possible, that conversion is applied to the
4858 chosen operand and the converted operand is used in place of
4859 the original operand for the remainder of this section. */
4860 if ((conv2
&& !conv2
->bad_p
4861 && conv3
&& !conv3
->bad_p
)
4862 || (conv2
&& conv2
->kind
== ck_ambig
)
4863 || (conv3
&& conv3
->kind
== ck_ambig
))
4865 if (complain
& tf_error
)
4867 error_at (loc
, "operands to ?: have different types %qT and %qT",
4868 arg2_type
, arg3_type
);
4869 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
4870 inform (loc
, " and each type can be converted to the other");
4871 else if (conv2
&& conv2
->kind
== ck_ambig
)
4872 convert_like (conv2
, arg2
, complain
);
4874 convert_like (conv3
, arg3
, complain
);
4876 result
= error_mark_node
;
4878 else if (conv2
&& !conv2
->bad_p
)
4880 arg2
= convert_like (conv2
, arg2
, complain
);
4881 arg2
= convert_from_reference (arg2
);
4882 arg2_type
= TREE_TYPE (arg2
);
4883 /* Even if CONV2 is a valid conversion, the result of the
4884 conversion may be invalid. For example, if ARG3 has type
4885 "volatile X", and X does not have a copy constructor
4886 accepting a "volatile X&", then even if ARG2 can be
4887 converted to X, the conversion will fail. */
4888 if (error_operand_p (arg2
))
4889 result
= error_mark_node
;
4892 else if (conv3
&& !conv3
->bad_p
)
4894 arg3
= convert_like (conv3
, arg3
, complain
);
4895 arg3
= convert_from_reference (arg3
);
4896 arg3_type
= TREE_TYPE (arg3
);
4897 if (error_operand_p (arg3
))
4898 result
= error_mark_node
;
4902 /* Free all the conversions we allocated. */
4903 obstack_free (&conversion_obstack
, p
);
4908 /* If, after the conversion, both operands have class type,
4909 treat the cv-qualification of both operands as if it were the
4910 union of the cv-qualification of the operands.
4912 The standard is not clear about what to do in this
4913 circumstance. For example, if the first operand has type
4914 "const X" and the second operand has a user-defined
4915 conversion to "volatile X", what is the type of the second
4916 operand after this step? Making it be "const X" (matching
4917 the first operand) seems wrong, as that discards the
4918 qualification without actually performing a copy. Leaving it
4919 as "volatile X" seems wrong as that will result in the
4920 conditional expression failing altogether, even though,
4921 according to this step, the one operand could be converted to
4922 the type of the other. */
4924 && CLASS_TYPE_P (arg2_type
)
4925 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
4926 arg2_type
= arg3_type
=
4927 cp_build_qualified_type (arg2_type
,
4928 cp_type_quals (arg2_type
)
4929 | cp_type_quals (arg3_type
));
4934 If the second and third operands are glvalues of the same value
4935 category and have the same type, the result is of that type and
4937 if (((real_lvalue_p (arg2
) && real_lvalue_p (arg3
))
4938 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
4939 && same_type_p (arg2_type
, arg3_type
))
4941 result_type
= arg2_type
;
4942 arg2
= mark_lvalue_use (arg2
);
4943 arg3
= mark_lvalue_use (arg3
);
4944 goto valid_operands
;
4949 Otherwise, the result is an rvalue. If the second and third
4950 operand do not have the same type, and either has (possibly
4951 cv-qualified) class type, overload resolution is used to
4952 determine the conversions (if any) to be applied to the operands
4953 (_over.match.oper_, _over.built_). */
4955 if (!same_type_p (arg2_type
, arg3_type
)
4956 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
4962 /* Rearrange the arguments so that add_builtin_candidate only has
4963 to know about two args. In build_builtin_candidate, the
4964 arguments are unscrambled. */
4968 add_builtin_candidates (&candidates
,
4971 ansi_opname (COND_EXPR
),
4973 LOOKUP_NORMAL
, complain
);
4977 If the overload resolution fails, the program is
4979 candidates
= splice_viable (candidates
, false, &any_viable_p
);
4982 if (complain
& tf_error
)
4983 error_at (loc
, "operands to ?: have different types %qT and %qT",
4984 arg2_type
, arg3_type
);
4985 return error_mark_node
;
4987 cand
= tourney (candidates
, complain
);
4990 if (complain
& tf_error
)
4992 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
4993 print_z_candidates (loc
, candidates
);
4995 return error_mark_node
;
5000 Otherwise, the conversions thus determined are applied, and
5001 the converted operands are used in place of the original
5002 operands for the remainder of this section. */
5003 conv
= cand
->convs
[0];
5004 arg1
= convert_like (conv
, arg1
, complain
);
5005 conv
= cand
->convs
[1];
5006 arg2
= convert_like (conv
, arg2
, complain
);
5007 arg2_type
= TREE_TYPE (arg2
);
5008 conv
= cand
->convs
[2];
5009 arg3
= convert_like (conv
, arg3
, complain
);
5010 arg3_type
= TREE_TYPE (arg3
);
5015 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5016 and function-to-pointer (_conv.func_) standard conversions are
5017 performed on the second and third operands.
5019 We need to force the lvalue-to-rvalue conversion here for class types,
5020 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5021 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5024 arg2
= force_rvalue (arg2
, complain
);
5025 if (!CLASS_TYPE_P (arg2_type
))
5026 arg2_type
= TREE_TYPE (arg2
);
5028 arg3
= force_rvalue (arg3
, complain
);
5029 if (!CLASS_TYPE_P (arg3_type
))
5030 arg3_type
= TREE_TYPE (arg3
);
5032 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5033 return error_mark_node
;
5037 After those conversions, one of the following shall hold:
5039 --The second and third operands have the same type; the result is of
5041 if (same_type_p (arg2_type
, arg3_type
))
5042 result_type
= arg2_type
;
5045 --The second and third operands have arithmetic or enumeration
5046 type; the usual arithmetic conversions are performed to bring
5047 them to a common type, and the result is of that type. */
5048 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5049 || UNSCOPED_ENUM_P (arg2_type
))
5050 && (ARITHMETIC_TYPE_P (arg3_type
)
5051 || UNSCOPED_ENUM_P (arg3_type
)))
5053 /* In this case, there is always a common type. */
5054 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5056 if (complain
& tf_warning
)
5057 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5058 "implicit conversion from %qT to %qT to "
5059 "match other result of conditional",
5062 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5063 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5065 if (TREE_CODE (orig_arg2
) == CONST_DECL
5066 && TREE_CODE (orig_arg3
) == CONST_DECL
5067 && DECL_CONTEXT (orig_arg2
) == DECL_CONTEXT (orig_arg3
))
5068 /* Two enumerators from the same enumeration can have different
5069 types when the enumeration is still being defined. */;
5070 else if (complain
& tf_warning
)
5071 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5072 "conditional expression: %qT vs %qT",
5073 arg2_type
, arg3_type
);
5075 else if (extra_warnings
5076 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5077 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5078 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5079 && !same_type_p (arg2_type
,
5080 type_promotes_to (arg3_type
)))))
5082 if (complain
& tf_warning
)
5083 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5084 "conditional expression");
5087 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5088 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5092 --The second and third operands have pointer type, or one has
5093 pointer type and the other is a null pointer constant; pointer
5094 conversions (_conv.ptr_) and qualification conversions
5095 (_conv.qual_) are performed to bring them to their composite
5096 pointer type (_expr.rel_). The result is of the composite
5099 --The second and third operands have pointer to member type, or
5100 one has pointer to member type and the other is a null pointer
5101 constant; pointer to member conversions (_conv.mem_) and
5102 qualification conversions (_conv.qual_) are performed to bring
5103 them to a common type, whose cv-qualification shall match the
5104 cv-qualification of either the second or the third operand.
5105 The result is of the common type. */
5106 else if ((null_ptr_cst_p (arg2
)
5107 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5108 || (null_ptr_cst_p (arg3
)
5109 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5110 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5111 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5112 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5114 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5115 arg3
, CPO_CONDITIONAL_EXPR
,
5117 if (result_type
== error_mark_node
)
5118 return error_mark_node
;
5119 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5120 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5125 if (complain
& tf_error
)
5126 error_at (loc
, "operands to ?: have different types %qT and %qT",
5127 arg2_type
, arg3_type
);
5128 return error_mark_node
;
5131 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5132 return error_mark_node
;
5135 result
= build3 (COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5136 if (!cp_unevaluated_operand
)
5137 /* Avoid folding within decltype (c++/42013) and noexcept. */
5138 result
= fold_if_not_in_template (result
);
5140 /* We can't use result_type below, as fold might have returned a
5145 /* Expand both sides into the same slot, hopefully the target of
5146 the ?: expression. We used to check for TARGET_EXPRs here,
5147 but now we sometimes wrap them in NOP_EXPRs so the test would
5149 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5150 result
= get_target_expr_sfinae (result
, complain
);
5151 /* If this expression is an rvalue, but might be mistaken for an
5152 lvalue, we must add a NON_LVALUE_EXPR. */
5153 result
= rvalue (result
);
5156 result
= force_paren_expr (result
);
5161 /* Wrapper for above. */
5164 build_conditional_expr (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
5165 tsubst_flags_t complain
)
5168 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5169 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5170 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5174 /* OPERAND is an operand to an expression. Perform necessary steps
5175 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5179 prep_operand (tree operand
)
5183 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5184 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5185 /* Make sure the template type is instantiated now. */
5186 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5192 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5193 OVERLOAD) to the CANDIDATES, returning an updated list of
5194 CANDIDATES. The ARGS are the arguments provided to the call;
5195 if FIRST_ARG is non-null it is the implicit object argument,
5196 otherwise the first element of ARGS is used if needed. The
5197 EXPLICIT_TARGS are explicit template arguments provided.
5198 TEMPLATE_ONLY is true if only template functions should be
5199 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5200 add_function_candidate. */
5203 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5205 tree explicit_targs
, bool template_only
,
5206 tree conversion_path
, tree access_path
,
5208 struct z_candidate
**candidates
,
5209 tsubst_flags_t complain
)
5212 const vec
<tree
, va_gc
> *non_static_args
;
5213 bool check_list_ctor
;
5214 bool check_converting
;
5215 unification_kind_t strict
;
5221 /* Precalculate special handling of constructors and conversion ops. */
5222 fn
= OVL_CURRENT (fns
);
5223 if (DECL_CONV_FN_P (fn
))
5225 check_list_ctor
= false;
5226 check_converting
= !!(flags
& LOOKUP_ONLYCONVERTING
);
5227 if (flags
& LOOKUP_NO_CONVERSION
)
5228 /* We're doing return_type(x). */
5229 strict
= DEDUCE_CONV
;
5231 /* We're doing x.operator return_type(). */
5232 strict
= DEDUCE_EXACT
;
5233 /* [over.match.funcs] For conversion functions, the function
5234 is considered to be a member of the class of the implicit
5235 object argument for the purpose of defining the type of
5236 the implicit object parameter. */
5237 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5241 if (DECL_CONSTRUCTOR_P (fn
))
5243 check_list_ctor
= !!(flags
& LOOKUP_LIST_ONLY
);
5244 /* For list-initialization we consider explicit constructors
5245 and complain if one is chosen. */
5247 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5248 == LOOKUP_ONLYCONVERTING
);
5252 check_list_ctor
= false;
5253 check_converting
= false;
5255 strict
= DEDUCE_CALL
;
5256 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5260 non_static_args
= args
;
5262 /* Delay creating the implicit this parameter until it is needed. */
5263 non_static_args
= NULL
;
5265 for (; fns
; fns
= OVL_NEXT (fns
))
5268 const vec
<tree
, va_gc
> *fn_args
;
5270 fn
= OVL_CURRENT (fns
);
5272 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5274 if (check_list_ctor
&& !is_list_ctor (fn
))
5277 /* Figure out which set of arguments to use. */
5278 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5280 /* If this function is a non-static member and we didn't get an
5281 implicit object argument, move it out of args. */
5282 if (first_arg
== NULL_TREE
)
5286 vec
<tree
, va_gc
> *tempvec
;
5287 vec_alloc (tempvec
, args
->length () - 1);
5288 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5289 tempvec
->quick_push (arg
);
5290 non_static_args
= tempvec
;
5291 first_arg
= (*args
)[0];
5294 fn_first_arg
= first_arg
;
5295 fn_args
= non_static_args
;
5299 /* Otherwise, just use the list of arguments provided. */
5300 fn_first_arg
= NULL_TREE
;
5304 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5305 add_template_candidate (candidates
,
5317 else if (!template_only
)
5318 add_function_candidate (candidates
,
5331 build_new_op_1 (location_t loc
, enum tree_code code
, int flags
, tree arg1
,
5332 tree arg2
, tree arg3
, tree
*overload
, tsubst_flags_t complain
)
5334 struct z_candidate
*candidates
= 0, *cand
;
5335 vec
<tree
, va_gc
> *arglist
;
5338 tree result
= NULL_TREE
;
5339 bool result_valid_p
= false;
5340 enum tree_code code2
= NOP_EXPR
;
5341 enum tree_code code_orig_arg1
= ERROR_MARK
;
5342 enum tree_code code_orig_arg2
= ERROR_MARK
;
5348 if (error_operand_p (arg1
)
5349 || error_operand_p (arg2
)
5350 || error_operand_p (arg3
))
5351 return error_mark_node
;
5353 if (code
== MODIFY_EXPR
)
5355 code2
= TREE_CODE (arg3
);
5357 fnname
= ansi_assopname (code2
);
5360 fnname
= ansi_opname (code
);
5362 arg1
= prep_operand (arg1
);
5364 bool memonly
= false;
5369 case VEC_DELETE_EXPR
:
5371 /* Use build_op_new_call and build_op_delete_call instead. */
5375 /* Use build_op_call instead. */
5378 case TRUTH_ORIF_EXPR
:
5379 case TRUTH_ANDIF_EXPR
:
5380 case TRUTH_AND_EXPR
:
5382 /* These are saved for the sake of warn_logical_operator. */
5383 code_orig_arg1
= TREE_CODE (arg1
);
5384 code_orig_arg2
= TREE_CODE (arg2
);
5392 /* These are saved for the sake of maybe_warn_bool_compare. */
5393 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5394 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5397 /* =, ->, [], () must be non-static member functions. */
5399 if (code2
!= NOP_EXPR
)
5410 arg2
= prep_operand (arg2
);
5411 arg3
= prep_operand (arg3
);
5413 if (code
== COND_EXPR
)
5414 /* Use build_conditional_expr instead. */
5416 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5417 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5420 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5421 arg2
= integer_zero_node
;
5423 vec_alloc (arglist
, 3);
5424 arglist
->quick_push (arg1
);
5425 if (arg2
!= NULL_TREE
)
5426 arglist
->quick_push (arg2
);
5427 if (arg3
!= NULL_TREE
)
5428 arglist
->quick_push (arg3
);
5430 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5431 p
= conversion_obstack_alloc (0);
5433 /* Add namespace-scope operators to the list of functions to
5436 add_candidates (lookup_function_nonclass (fnname
, arglist
,
5438 NULL_TREE
, arglist
, NULL_TREE
,
5439 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5440 flags
, &candidates
, complain
);
5444 args
[2] = NULL_TREE
;
5446 /* Add class-member operators to the candidate set. */
5447 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5451 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5452 if (fns
== error_mark_node
)
5454 result
= error_mark_node
;
5455 goto user_defined_result_ready
;
5458 add_candidates (BASELINK_FUNCTIONS (fns
),
5459 NULL_TREE
, arglist
, NULL_TREE
,
5461 BASELINK_BINFO (fns
),
5462 BASELINK_ACCESS_BINFO (fns
),
5463 flags
, &candidates
, complain
);
5465 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5466 only non-member functions that have type T1 or reference to
5467 cv-qualified-opt T1 for the first argument, if the first argument
5468 has an enumeration type, or T2 or reference to cv-qualified-opt
5469 T2 for the second argument, if the second argument has an
5470 enumeration type. Filter out those that don't match. */
5471 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5473 struct z_candidate
**candp
, **next
;
5475 for (candp
= &candidates
; *candp
; candp
= next
)
5477 tree parmlist
, parmtype
;
5478 int i
, nargs
= (arg2
? 2 : 1);
5483 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5485 for (i
= 0; i
< nargs
; ++i
)
5487 parmtype
= TREE_VALUE (parmlist
);
5489 if (TREE_CODE (parmtype
) == REFERENCE_TYPE
)
5490 parmtype
= TREE_TYPE (parmtype
);
5491 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5492 && (same_type_ignoring_top_level_qualifiers_p
5493 (TREE_TYPE (args
[i
]), parmtype
)))
5496 parmlist
= TREE_CHAIN (parmlist
);
5499 /* No argument has an appropriate type, so remove this
5500 candidate function from the list. */
5503 *candp
= cand
->next
;
5509 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5516 /* For these, the built-in candidates set is empty
5517 [over.match.oper]/3. We don't want non-strict matches
5518 because exact matches are always possible with built-in
5519 operators. The built-in candidate set for COMPONENT_REF
5520 would be empty too, but since there are no such built-in
5521 operators, we accept non-strict matches for them. */
5530 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5535 case POSTINCREMENT_EXPR
:
5536 case POSTDECREMENT_EXPR
:
5537 /* Don't try anything fancy if we're not allowed to produce
5539 if (!(complain
& tf_error
))
5540 return error_mark_node
;
5542 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5543 distinguish between prefix and postfix ++ and
5544 operator++() was used for both, so we allow this with
5548 const char *msg
= (flag_permissive
)
5549 ? G_("no %<%D(int)%> declared for postfix %qs,"
5550 " trying prefix operator instead")
5551 : G_("no %<%D(int)%> declared for postfix %qs");
5552 permerror (loc
, msg
, fnname
, operator_name_info
[code
].name
);
5555 if (!flag_permissive
)
5556 return error_mark_node
;
5558 if (code
== POSTINCREMENT_EXPR
)
5559 code
= PREINCREMENT_EXPR
;
5561 code
= PREDECREMENT_EXPR
;
5562 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5563 NULL_TREE
, overload
, complain
);
5566 /* The caller will deal with these. */
5571 result_valid_p
= true;
5575 if (complain
& tf_error
)
5577 /* If one of the arguments of the operator represents
5578 an invalid use of member function pointer, try to report
5579 a meaningful error ... */
5580 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
5581 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
5582 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
5583 /* We displayed the error message. */;
5586 /* ... Otherwise, report the more generic
5587 "no matching operator found" error */
5588 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
5589 print_z_candidates (loc
, candidates
);
5592 result
= error_mark_node
;
5598 cand
= tourney (candidates
, complain
);
5601 if (complain
& tf_error
)
5603 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
5604 print_z_candidates (loc
, candidates
);
5606 result
= error_mark_node
;
5608 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
5611 *overload
= cand
->fn
;
5613 if (resolve_args (arglist
, complain
) == NULL
)
5614 result
= error_mark_node
;
5616 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
5620 /* Give any warnings we noticed during overload resolution. */
5621 if (cand
->warnings
&& (complain
& tf_warning
))
5623 struct candidate_warning
*w
;
5624 for (w
= cand
->warnings
; w
; w
= w
->next
)
5625 joust (cand
, w
->loser
, 1, complain
);
5628 /* Check for comparison of different enum types. */
5637 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
5638 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
5639 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
5640 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
5641 && (complain
& tf_warning
))
5643 warning (OPT_Wenum_compare
,
5644 "comparison between %q#T and %q#T",
5645 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
5652 /* We need to strip any leading REF_BIND so that bitfields
5653 don't cause errors. This should not remove any important
5654 conversions, because builtins don't apply to class
5655 objects directly. */
5656 conv
= cand
->convs
[0];
5657 if (conv
->kind
== ck_ref_bind
)
5658 conv
= next_conversion (conv
);
5659 arg1
= convert_like (conv
, arg1
, complain
);
5663 conv
= cand
->convs
[1];
5664 if (conv
->kind
== ck_ref_bind
)
5665 conv
= next_conversion (conv
);
5667 arg2
= decay_conversion (arg2
, complain
);
5669 /* We need to call warn_logical_operator before
5670 converting arg2 to a boolean_type, but after
5671 decaying an enumerator to its value. */
5672 if (complain
& tf_warning
)
5673 warn_logical_operator (loc
, code
, boolean_type_node
,
5674 code_orig_arg1
, arg1
,
5675 code_orig_arg2
, arg2
);
5677 arg2
= convert_like (conv
, arg2
, complain
);
5681 conv
= cand
->convs
[2];
5682 if (conv
->kind
== ck_ref_bind
)
5683 conv
= next_conversion (conv
);
5684 arg3
= convert_like (conv
, arg3
, complain
);
5690 user_defined_result_ready
:
5692 /* Free all the conversions we allocated. */
5693 obstack_free (&conversion_obstack
, p
);
5695 if (result
|| result_valid_p
)
5702 return cp_build_modify_expr (arg1
, code2
, arg2
, complain
);
5705 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
5707 case TRUTH_ANDIF_EXPR
:
5708 case TRUTH_ORIF_EXPR
:
5709 case TRUTH_AND_EXPR
:
5711 if (complain
& tf_warning
)
5712 warn_logical_operator (loc
, code
, boolean_type_node
,
5713 code_orig_arg1
, arg1
, code_orig_arg2
, arg2
);
5721 if ((complain
& tf_warning
)
5722 && ((code_orig_arg1
== BOOLEAN_TYPE
)
5723 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
5724 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
5725 if (complain
& tf_warning
&& warn_tautological_compare
)
5726 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
5731 case TRUNC_DIV_EXPR
:
5736 case TRUNC_MOD_EXPR
:
5740 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
5742 case UNARY_PLUS_EXPR
:
5745 case TRUTH_NOT_EXPR
:
5746 case PREINCREMENT_EXPR
:
5747 case POSTINCREMENT_EXPR
:
5748 case PREDECREMENT_EXPR
:
5749 case POSTDECREMENT_EXPR
:
5753 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
5756 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
5759 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
5763 /* The caller will deal with these. */
5775 /* Wrapper for above. */
5778 build_new_op (location_t loc
, enum tree_code code
, int flags
,
5779 tree arg1
, tree arg2
, tree arg3
,
5780 tree
*overload
, tsubst_flags_t complain
)
5783 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5784 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
5785 overload
, complain
);
5786 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5790 /* Returns true if FN has two parameters, of which the second has type
5794 second_parm_is_size_t (tree fn
)
5796 tree t
= FUNCTION_ARG_CHAIN (fn
);
5798 && same_type_p (TREE_VALUE (t
), size_type_node
)
5799 && TREE_CHAIN (t
) == void_list_node
);
5802 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5803 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5806 non_placement_deallocation_fn_p (tree t
)
5808 /* A template instance is never a usual deallocation function,
5809 regardless of its signature. */
5810 if (TREE_CODE (t
) == TEMPLATE_DECL
5811 || primary_template_instantiation_p (t
))
5814 /* If a class T has a member deallocation function named operator delete
5815 with exactly one parameter, then that function is a usual
5816 (non-placement) deallocation function. If class T does not declare
5817 such an operator delete but does declare a member deallocation
5818 function named operator delete with exactly two parameters, the second
5819 of which has type std::size_t (18.2), then this function is a usual
5820 deallocation function. */
5821 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
5822 if (FUNCTION_ARG_CHAIN (t
) == void_list_node
5823 || ((!global
|| flag_sized_deallocation
)
5824 && second_parm_is_size_t (t
)))
5829 /* Build a call to operator delete. This has to be handled very specially,
5830 because the restrictions on what signatures match are different from all
5831 other call instances. For a normal delete, only a delete taking (void *)
5832 or (void *, size_t) is accepted. For a placement delete, only an exact
5833 match with the placement new is accepted.
5835 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5836 ADDR is the pointer to be deleted.
5837 SIZE is the size of the memory block to be deleted.
5838 GLOBAL_P is true if the delete-expression should not consider
5839 class-specific delete operators.
5840 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5842 If this call to "operator delete" is being generated as part to
5843 deallocate memory allocated via a new-expression (as per [expr.new]
5844 which requires that if the initialization throws an exception then
5845 we call a deallocation function), then ALLOC_FN is the allocation
5849 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
5850 bool global_p
, tree placement
,
5851 tree alloc_fn
, tsubst_flags_t complain
)
5853 tree fn
= NULL_TREE
;
5854 tree fns
, fnname
, type
, t
;
5856 if (addr
== error_mark_node
)
5857 return error_mark_node
;
5859 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
5861 fnname
= ansi_opname (code
);
5863 if (CLASS_TYPE_P (type
)
5864 && COMPLETE_TYPE_P (complete_type (type
))
5868 If the result of the lookup is ambiguous or inaccessible, or if
5869 the lookup selects a placement deallocation function, the
5870 program is ill-formed.
5872 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5874 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
5875 if (fns
== error_mark_node
)
5876 return error_mark_node
;
5881 if (fns
== NULL_TREE
)
5882 fns
= lookup_name_nonclass (fnname
);
5884 /* Strip const and volatile from addr. */
5885 addr
= cp_convert (ptr_type_node
, addr
, complain
);
5889 /* "A declaration of a placement deallocation function matches the
5890 declaration of a placement allocation function if it has the same
5891 number of parameters and, after parameter transformations (8.3.5),
5892 all parameter types except the first are identical."
5894 So we build up the function type we want and ask instantiate_type
5895 to get it for us. */
5896 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
5897 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
5898 t
= build_function_type (void_type_node
, t
);
5900 fn
= instantiate_type (t
, fns
, tf_none
);
5901 if (fn
== error_mark_node
)
5904 if (BASELINK_P (fn
))
5905 fn
= BASELINK_FUNCTIONS (fn
);
5907 /* "If the lookup finds the two-parameter form of a usual deallocation
5908 function (3.7.4.2) and that function, considered as a placement
5909 deallocation function, would have been selected as a match for the
5910 allocation function, the program is ill-formed." */
5911 if (second_parm_is_size_t (fn
))
5914 = G_("exception cleanup for this placement new selects "
5915 "non-placement operator delete");
5917 = G_("%qD is a usual (non-placement) deallocation "
5918 "function in C++14 (or with -fsized-deallocation)");
5920 /* But if the class has an operator delete (void *), then that is
5921 the usual deallocation function, so we shouldn't complain
5922 about using the operator delete (void *, size_t). */
5923 if (DECL_CLASS_SCOPE_P (fn
))
5924 for (t
= BASELINK_P (fns
) ? BASELINK_FUNCTIONS (fns
) : fns
;
5925 t
; t
= OVL_NEXT (t
))
5927 tree elt
= OVL_CURRENT (t
);
5928 if (non_placement_deallocation_fn_p (elt
)
5929 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
5932 /* Before C++14 a two-parameter global deallocation function is
5933 always a placement deallocation function, but warn if
5935 else if (!flag_sized_deallocation
)
5937 if ((complain
& tf_warning
)
5938 && warning (OPT_Wc__14_compat
, msg1
))
5939 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
5943 if (complain
& tf_warning_or_error
)
5945 if (permerror (input_location
, msg1
))
5947 /* Only mention C++14 for namespace-scope delete. */
5948 if (DECL_NAMESPACE_SCOPE_P (fn
))
5949 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
5951 inform (DECL_SOURCE_LOCATION (fn
),
5952 "%qD is a usual (non-placement) deallocation "
5957 return error_mark_node
;
5962 /* "Any non-placement deallocation function matches a non-placement
5963 allocation function. If the lookup finds a single matching
5964 deallocation function, that function will be called; otherwise, no
5965 deallocation function will be called." */
5966 for (t
= BASELINK_P (fns
) ? BASELINK_FUNCTIONS (fns
) : fns
;
5967 t
; t
= OVL_NEXT (t
))
5969 tree elt
= OVL_CURRENT (t
);
5970 if (non_placement_deallocation_fn_p (elt
))
5973 /* "If a class T has a member deallocation function named
5974 operator delete with exactly one parameter, then that
5975 function is a usual (non-placement) deallocation
5976 function. If class T does not declare such an operator
5977 delete but does declare a member deallocation function named
5978 operator delete with exactly two parameters, the second of
5979 which has type std::size_t (18.2), then this function is a
5980 usual deallocation function."
5982 So in a class (void*) beats (void*, size_t). */
5983 if (DECL_CLASS_SCOPE_P (fn
))
5985 if (FUNCTION_ARG_CHAIN (fn
) == void_list_node
)
5988 /* At global scope (in C++14 and above) the rules are different:
5990 If deallocation function lookup finds both a usual
5991 deallocation function with only a pointer parameter and a
5992 usual deallocation function with both a pointer parameter
5993 and a size parameter, the function to be called is selected
5996 * If the type is complete and if, for the second alternative
5997 (delete array) only, the operand is a pointer to a class
5998 type with a non-trivial destructor or a (possibly
5999 multi-dimensional) array thereof, the function with two
6000 parameters is selected.
6002 * Otherwise, it is unspecified which of the two deallocation
6003 functions is selected. */
6006 bool want_size
= COMPLETE_TYPE_P (type
);
6007 if (code
== VEC_DELETE_EXPR
6008 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6009 /* We need a cookie to determine the array size. */
6011 bool have_size
= (FUNCTION_ARG_CHAIN (fn
) != void_list_node
);
6012 if (want_size
== have_size
)
6018 /* If we have a matching function, call it. */
6021 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6023 /* If the FN is a member function, make sure that it is
6025 if (BASELINK_P (fns
))
6026 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6029 /* Core issue 901: It's ok to new a type with deleted delete. */
6030 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6035 /* The placement args might not be suitable for overload
6036 resolution at this point, so build the call directly. */
6037 int nargs
= call_expr_nargs (placement
);
6038 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6041 for (i
= 1; i
< nargs
; i
++)
6042 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6043 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6044 return error_mark_node
;
6045 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6050 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6051 args
->quick_push (addr
);
6052 if (FUNCTION_ARG_CHAIN (fn
) != void_list_node
)
6053 args
->quick_push (size
);
6054 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6055 release_tree_vector (args
);
6062 If no unambiguous matching deallocation function can be found,
6063 propagating the exception does not cause the object's memory to
6067 if ((complain
& tf_warning
)
6069 warning (0, "no corresponding deallocation function for %qD",
6074 if (complain
& tf_error
)
6075 error ("no suitable %<operator %s%> for %qT",
6076 operator_name_info
[(int)code
].name
, type
);
6077 return error_mark_node
;
6080 /* If the current scope isn't allowed to access DECL along
6081 BASETYPE_PATH, give an error. The most derived class in
6082 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6083 the declaration to use in the error diagnostic. */
6086 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6087 tsubst_flags_t complain
)
6089 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6091 if (!accessible_p (basetype_path
, decl
, true))
6093 if (complain
& tf_error
)
6095 if (TREE_PRIVATE (decl
))
6097 error ("%q#D is private within this context", diag_decl
);
6098 inform (DECL_SOURCE_LOCATION (diag_decl
),
6099 "declared private here");
6101 else if (TREE_PROTECTED (decl
))
6103 error ("%q#D is protected within this context", diag_decl
);
6104 inform (DECL_SOURCE_LOCATION (diag_decl
),
6105 "declared protected here");
6109 error ("%q#D is inaccessible within this context", diag_decl
);
6110 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6119 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6120 bitwise or of LOOKUP_* values. If any errors are warnings are
6121 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6122 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6126 build_temp (tree expr
, tree type
, int flags
,
6127 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6130 vec
<tree
, va_gc
> *args
;
6132 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6133 args
= make_tree_vector_single (expr
);
6134 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6135 &args
, type
, flags
, complain
);
6136 release_tree_vector (args
);
6137 if (warningcount
+ werrorcount
> savew
)
6138 *diagnostic_kind
= DK_WARNING
;
6139 else if (errorcount
> savee
)
6140 *diagnostic_kind
= DK_ERROR
;
6142 *diagnostic_kind
= DK_UNSPECIFIED
;
6146 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6147 EXPR is implicitly converted to type TOTYPE.
6148 FN and ARGNUM are used for diagnostics. */
6151 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6153 /* Issue warnings about peculiar, but valid, uses of NULL. */
6154 if (expr
== null_node
&& TREE_CODE (totype
) != BOOLEAN_TYPE
6155 && ARITHMETIC_TYPE_P (totype
))
6157 source_location loc
=
6158 expansion_point_location_if_in_system_header (input_location
);
6161 warning_at (loc
, OPT_Wconversion_null
,
6162 "passing NULL to non-pointer argument %P of %qD",
6165 warning_at (loc
, OPT_Wconversion_null
,
6166 "converting to non-pointer type %qT from NULL", totype
);
6169 /* Issue warnings if "false" is converted to a NULL pointer */
6170 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6171 && TYPE_PTR_P (totype
))
6174 warning_at (input_location
, OPT_Wconversion_null
,
6175 "converting %<false%> to pointer type for argument %P "
6176 "of %qD", argnum
, fn
);
6178 warning_at (input_location
, OPT_Wconversion_null
,
6179 "converting %<false%> to pointer type %qT", totype
);
6183 /* We gave a diagnostic during a conversion. If this was in the second
6184 standard conversion sequence of a user-defined conversion sequence, say
6185 which user-defined conversion. */
6188 maybe_print_user_conv_context (conversion
*convs
)
6190 if (convs
->user_conv_p
)
6191 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6192 if (t
->kind
== ck_user
)
6194 print_z_candidate (0, " after user-defined conversion:",
6200 /* Perform the conversions in CONVS on the expression EXPR. FN and
6201 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6202 indicates the `this' argument of a method. INNER is nonzero when
6203 being called to continue a conversion chain. It is negative when a
6204 reference binding will be applied, positive otherwise. If
6205 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6206 conversions will be emitted if appropriate. If C_CAST_P is true,
6207 this conversion is coming from a C-style cast; in that case,
6208 conversions to inaccessible bases are permitted. */
6211 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6212 int inner
, bool issue_conversion_warnings
,
6213 bool c_cast_p
, tsubst_flags_t complain
)
6215 tree totype
= convs
->type
;
6216 diagnostic_t diag_kind
;
6218 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6220 if (convs
->bad_p
&& !(complain
& tf_error
))
6221 return error_mark_node
;
6224 && convs
->kind
!= ck_user
6225 && convs
->kind
!= ck_list
6226 && convs
->kind
!= ck_ambig
6227 && (convs
->kind
!= ck_ref_bind
6228 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6229 && (convs
->kind
!= ck_rvalue
6230 || SCALAR_TYPE_P (totype
))
6231 && convs
->kind
!= ck_base
)
6233 bool complained
= false;
6234 conversion
*t
= convs
;
6236 /* Give a helpful error if this is bad because of excess braces. */
6237 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6238 && SCALAR_TYPE_P (totype
)
6239 && CONSTRUCTOR_NELTS (expr
) > 0
6240 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6242 complained
= permerror (loc
, "too many braces around initializer "
6244 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6245 && CONSTRUCTOR_NELTS (expr
) == 1)
6246 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6249 /* Give a helpful error if this is bad because a conversion to bool
6250 from std::nullptr_t requires direct-initialization. */
6251 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6252 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6253 complained
= permerror (loc
, "converting to %qT from %qT requires "
6254 "direct-initialization",
6255 totype
, TREE_TYPE (expr
));
6257 for (; t
; t
= next_conversion (t
))
6259 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6261 complained
= permerror (loc
, "invalid user-defined conversion "
6262 "from %qT to %qT", TREE_TYPE (expr
),
6265 print_z_candidate (loc
, "candidate is:", t
->cand
);
6266 expr
= convert_like_real (t
, expr
, fn
, argnum
, 1,
6267 /*issue_conversion_warnings=*/false,
6270 if (convs
->kind
== ck_ref_bind
)
6271 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6272 LOOKUP_NORMAL
, NULL_TREE
,
6275 expr
= cp_convert (totype
, expr
, complain
);
6276 if (complained
&& fn
)
6277 inform (DECL_SOURCE_LOCATION (fn
),
6278 " initializing argument %P of %qD", argnum
, fn
);
6281 else if (t
->kind
== ck_user
|| !t
->bad_p
)
6283 expr
= convert_like_real (t
, expr
, fn
, argnum
, 1,
6284 /*issue_conversion_warnings=*/false,
6289 else if (t
->kind
== ck_ambig
)
6290 return convert_like_real (t
, expr
, fn
, argnum
, 1,
6291 /*issue_conversion_warnings=*/false,
6294 else if (t
->kind
== ck_identity
)
6298 complained
= permerror (loc
, "invalid conversion from %qT to %qT",
6299 TREE_TYPE (expr
), totype
);
6300 if (complained
&& fn
)
6301 inform (DECL_SOURCE_LOCATION (fn
),
6302 " initializing argument %P of %qD", argnum
, fn
);
6304 return cp_convert (totype
, expr
, complain
);
6307 if (issue_conversion_warnings
&& (complain
& tf_warning
))
6308 conversion_null_warnings (totype
, expr
, fn
, argnum
);
6310 switch (convs
->kind
)
6314 struct z_candidate
*cand
= convs
->cand
;
6315 tree convfn
= cand
->fn
;
6318 /* If we're initializing from {}, it's value-initialization. Note
6319 that under the resolution of core 1630, value-initialization can
6320 use explicit constructors. */
6321 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6322 && CONSTRUCTOR_NELTS (expr
) == 0
6323 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
6325 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
6326 expr
= build_value_init (totype
, complain
);
6327 expr
= get_target_expr_sfinae (expr
, complain
);
6328 if (expr
!= error_mark_node
)
6330 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6331 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
6336 /* When converting from an init list we consider explicit
6337 constructors, but actually trying to call one is an error. */
6338 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
6339 /* Unless this is for direct-list-initialization. */
6340 && !DIRECT_LIST_INIT_P (expr
))
6342 if (!(complain
& tf_error
))
6343 return error_mark_node
;
6344 error ("converting to %qT from initializer list would use "
6345 "explicit constructor %qD", totype
, convfn
);
6348 expr
= mark_rvalue_use (expr
);
6350 /* Set user_conv_p on the argument conversions, so rvalue/base
6351 handling knows not to allow any more UDCs. */
6352 for (i
= 0; i
< cand
->num_convs
; ++i
)
6353 cand
->convs
[i
]->user_conv_p
= true;
6355 expr
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6357 /* If this is a constructor or a function returning an aggr type,
6358 we need to build up a TARGET_EXPR. */
6359 if (DECL_CONSTRUCTOR_P (convfn
))
6361 expr
= build_cplus_new (totype
, expr
, complain
);
6363 /* Remember that this was list-initialization. */
6364 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
6365 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6371 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
6373 int nelts
= CONSTRUCTOR_NELTS (expr
);
6375 expr
= build_value_init (totype
, complain
);
6376 else if (nelts
== 1)
6377 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6381 expr
= mark_rvalue_use (expr
);
6383 if (type_unknown_p (expr
))
6384 expr
= instantiate_type (totype
, expr
, complain
);
6385 /* Convert a constant to its underlying value, unless we are
6386 about to bind it to a reference, in which case we need to
6387 leave it as an lvalue. */
6390 expr
= scalar_constant_value (expr
);
6391 if (expr
== null_node
&& INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
6392 /* If __null has been converted to an integer type, we do not
6393 want to warn about uses of EXPR as an integer, rather than
6395 expr
= build_int_cst (totype
, 0);
6399 /* We leave bad_p off ck_ambig because overload resolution considers
6400 it valid, it just fails when we try to perform it. So we need to
6401 check complain here, too. */
6402 if (complain
& tf_error
)
6404 /* Call build_user_type_conversion again for the error. */
6405 build_user_type_conversion (totype
, convs
->u
.expr
, LOOKUP_NORMAL
,
6408 inform (DECL_SOURCE_LOCATION (fn
),
6409 " initializing argument %P of %qD", argnum
, fn
);
6411 return error_mark_node
;
6415 /* Conversion to std::initializer_list<T>. */
6416 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
6417 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
6418 unsigned len
= CONSTRUCTOR_NELTS (expr
);
6419 tree array
, val
, field
;
6420 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
6423 /* Convert all the elements. */
6424 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
6426 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
, argnum
,
6427 1, false, false, complain
);
6428 if (sub
== error_mark_node
)
6430 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
6431 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
6432 return error_mark_node
;
6433 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
), NULL_TREE
, sub
);
6434 if (!TREE_CONSTANT (sub
))
6435 TREE_CONSTANT (new_ctor
) = false;
6437 /* Build up the array. */
6438 elttype
= cp_build_qualified_type
6439 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
6440 array
= build_array_of_n_type (elttype
, len
);
6441 array
= finish_compound_literal (array
, new_ctor
, complain
);
6442 /* Take the address explicitly rather than via decay_conversion
6443 to avoid the error about taking the address of a temporary. */
6444 array
= cp_build_addr_expr (array
, complain
);
6445 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
6446 if (array
== error_mark_node
)
6447 return error_mark_node
;
6449 /* Build up the initializer_list object. */
6450 totype
= complete_type (totype
);
6451 field
= next_initializable_field (TYPE_FIELDS (totype
));
6452 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
6453 field
= next_initializable_field (DECL_CHAIN (field
));
6454 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
6455 new_ctor
= build_constructor (totype
, vec
);
6456 return get_target_expr_sfinae (new_ctor
, complain
);
6460 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
6462 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6463 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
6464 real
= perform_implicit_conversion (TREE_TYPE (totype
),
6466 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
6468 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
6469 return fold_if_not_in_template (expr
);
6471 expr
= reshape_init (totype
, expr
, complain
);
6472 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
6474 if (expr
!= error_mark_node
)
6475 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6482 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
6483 convs
->kind
== ck_ref_bind
? -1 : 1,
6484 convs
->kind
== ck_ref_bind
? issue_conversion_warnings
: false,
6487 if (expr
== error_mark_node
)
6488 return error_mark_node
;
6490 switch (convs
->kind
)
6493 expr
= decay_conversion (expr
, complain
);
6494 if (expr
== error_mark_node
)
6495 return error_mark_node
;
6497 if (! MAYBE_CLASS_TYPE_P (totype
))
6499 /* Else fall through. */
6501 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
6503 /* We are going to bind a reference directly to a base-class
6504 subobject of EXPR. */
6505 /* Build an expression for `*((base*) &expr)'. */
6506 expr
= convert_to_base (expr
, totype
,
6507 !c_cast_p
, /*nonnull=*/true, complain
);
6511 /* Copy-initialization where the cv-unqualified version of the source
6512 type is the same class as, or a derived class of, the class of the
6513 destination [is treated as direct-initialization]. [dcl.init] */
6514 flags
= LOOKUP_NORMAL
;
6515 if (convs
->user_conv_p
)
6516 /* This conversion is being done in the context of a user-defined
6517 conversion (i.e. the second step of copy-initialization), so
6518 don't allow any more. */
6519 flags
|= LOOKUP_NO_CONVERSION
;
6521 flags
|= LOOKUP_ONLYCONVERTING
;
6522 if (convs
->rvaluedness_matches_p
)
6523 flags
|= LOOKUP_PREFER_RVALUE
;
6524 if (TREE_CODE (expr
) == TARGET_EXPR
6525 && TARGET_EXPR_LIST_INIT_P (expr
))
6526 /* Copy-list-initialization doesn't actually involve a copy. */
6528 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
6529 if (diag_kind
&& complain
)
6531 maybe_print_user_conv_context (convs
);
6533 inform (DECL_SOURCE_LOCATION (fn
),
6534 " initializing argument %P of %qD", argnum
, fn
);
6537 return build_cplus_new (totype
, expr
, complain
);
6541 tree ref_type
= totype
;
6543 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
6545 tree extype
= TREE_TYPE (expr
);
6546 if (TYPE_REF_IS_RVALUE (ref_type
)
6547 && real_lvalue_p (expr
))
6548 error_at (loc
, "cannot bind %qT lvalue to %qT",
6550 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !real_lvalue_p (expr
)
6551 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
6552 error_at (loc
, "invalid initialization of non-const reference of "
6553 "type %qT from an rvalue of type %qT", totype
, extype
);
6554 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
6555 error_at (loc
, "binding %qT to reference of type %qT "
6556 "discards qualifiers", extype
, totype
);
6559 maybe_print_user_conv_context (convs
);
6561 inform (DECL_SOURCE_LOCATION (fn
),
6562 " initializing argument %P of %qD", argnum
, fn
);
6563 return error_mark_node
;
6566 /* If necessary, create a temporary.
6568 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
6569 that need temporaries, even when their types are reference
6570 compatible with the type of reference being bound, so the
6571 upcoming call to cp_build_addr_expr doesn't fail. */
6572 if (convs
->need_temporary_p
6573 || TREE_CODE (expr
) == CONSTRUCTOR
6574 || TREE_CODE (expr
) == VA_ARG_EXPR
)
6576 /* Otherwise, a temporary of type "cv1 T1" is created and
6577 initialized from the initializer expression using the rules
6578 for a non-reference copy-initialization (8.5). */
6580 tree type
= TREE_TYPE (ref_type
);
6581 cp_lvalue_kind lvalue
= real_lvalue_p (expr
);
6583 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6584 (type
, next_conversion (convs
)->type
));
6585 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
6586 && !TYPE_REF_IS_RVALUE (ref_type
))
6588 /* If the reference is volatile or non-const, we
6589 cannot create a temporary. */
6590 if (lvalue
& clk_bitfield
)
6591 error_at (loc
, "cannot bind bitfield %qE to %qT",
6593 else if (lvalue
& clk_packed
)
6594 error_at (loc
, "cannot bind packed field %qE to %qT",
6597 error_at (loc
, "cannot bind rvalue %qE to %qT",
6599 return error_mark_node
;
6601 /* If the source is a packed field, and we must use a copy
6602 constructor, then building the target expr will require
6603 binding the field to the reference parameter to the
6604 copy constructor, and we'll end up with an infinite
6605 loop. If we can use a bitwise copy, then we'll be
6607 if ((lvalue
& clk_packed
)
6608 && CLASS_TYPE_P (type
)
6609 && type_has_nontrivial_copy_init (type
))
6611 error_at (loc
, "cannot bind packed field %qE to %qT",
6613 return error_mark_node
;
6615 if (lvalue
& clk_bitfield
)
6617 expr
= convert_bitfield_to_declared_type (expr
);
6618 expr
= fold_convert (type
, expr
);
6620 expr
= build_target_expr_with_type (expr
, type
, complain
);
6623 /* Take the address of the thing to which we will bind the
6625 expr
= cp_build_addr_expr (expr
, complain
);
6626 if (expr
== error_mark_node
)
6627 return error_mark_node
;
6629 /* Convert it to a pointer to the type referred to by the
6630 reference. This will adjust the pointer if a derived to
6631 base conversion is being performed. */
6632 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
6634 /* Convert the pointer to the desired reference type. */
6635 return build_nop (ref_type
, expr
);
6639 return decay_conversion (expr
, complain
);
6642 /* Warn about deprecated conversion if appropriate. */
6643 string_conv_p (totype
, expr
, 1);
6648 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
6649 /*nonnull=*/false, complain
);
6650 return build_nop (totype
, expr
);
6653 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
6654 c_cast_p
, complain
);
6660 if (convs
->check_narrowing
6661 && !check_narrowing (totype
, expr
, complain
))
6662 return error_mark_node
;
6664 if (issue_conversion_warnings
)
6665 expr
= cp_convert_and_check (totype
, expr
, complain
);
6667 expr
= cp_convert (totype
, expr
, complain
);
6672 /* ARG is being passed to a varargs function. Perform any conversions
6673 required. Return the converted value. */
6676 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
6679 location_t loc
= EXPR_LOC_OR_LOC (arg
, input_location
);
6683 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6684 standard conversions are performed. */
6685 arg
= decay_conversion (arg
, complain
);
6686 arg_type
= TREE_TYPE (arg
);
6689 If the argument has integral or enumeration type that is subject
6690 to the integral promotions (_conv.prom_), or a floating point
6691 type that is subject to the floating point promotion
6692 (_conv.fpprom_), the value of the argument is converted to the
6693 promoted type before the call. */
6694 if (TREE_CODE (arg_type
) == REAL_TYPE
6695 && (TYPE_PRECISION (arg_type
)
6696 < TYPE_PRECISION (double_type_node
))
6697 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
6699 if ((complain
& tf_warning
)
6700 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
6701 warning_at (loc
, OPT_Wdouble_promotion
,
6702 "implicit conversion from %qT to %qT when passing "
6703 "argument to function",
6704 arg_type
, double_type_node
);
6705 arg
= convert_to_real (double_type_node
, arg
);
6707 else if (NULLPTR_TYPE_P (arg_type
))
6708 arg
= null_pointer_node
;
6709 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
6711 if (SCOPED_ENUM_P (arg_type
))
6713 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
6715 prom
= cp_perform_integral_promotions (prom
, complain
);
6716 if (abi_version_crosses (6)
6717 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
6718 && (complain
& tf_warning
))
6719 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
6720 "%qT before -fabi-version=6, %qT after", arg_type
,
6721 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
6722 if (!abi_version_at_least (6))
6726 arg
= cp_perform_integral_promotions (arg
, complain
);
6729 arg
= require_complete_type_sfinae (arg
, complain
);
6730 arg_type
= TREE_TYPE (arg
);
6732 if (arg
!= error_mark_node
6733 /* In a template (or ill-formed code), we can have an incomplete type
6734 even after require_complete_type_sfinae, in which case we don't know
6735 whether it has trivial copy or not. */
6736 && COMPLETE_TYPE_P (arg_type
))
6738 /* Build up a real lvalue-to-rvalue conversion in case the
6739 copy constructor is trivial but not callable. */
6740 if (!cp_unevaluated_operand
&& CLASS_TYPE_P (arg_type
))
6741 force_rvalue (arg
, complain
);
6743 /* [expr.call] 5.2.2/7:
6744 Passing a potentially-evaluated argument of class type (Clause 9)
6745 with a non-trivial copy constructor or a non-trivial destructor
6746 with no corresponding parameter is conditionally-supported, with
6747 implementation-defined semantics.
6749 We support it as pass-by-invisible-reference, just like a normal
6752 If the call appears in the context of a sizeof expression,
6753 it is not potentially-evaluated. */
6754 if (cp_unevaluated_operand
== 0
6755 && (type_has_nontrivial_copy_init (arg_type
)
6756 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
)))
6758 if (complain
& tf_warning
)
6759 warning (OPT_Wconditionally_supported
,
6760 "passing objects of non-trivially-copyable "
6761 "type %q#T through %<...%> is conditionally supported",
6763 return cp_build_addr_expr (arg
, complain
);
6770 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6773 build_x_va_arg (source_location loc
, tree expr
, tree type
)
6775 if (processing_template_decl
)
6777 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
6778 SET_EXPR_LOCATION (r
, loc
);
6782 type
= complete_type_or_else (type
, NULL_TREE
);
6784 if (expr
== error_mark_node
|| !type
)
6785 return error_mark_node
;
6787 expr
= mark_lvalue_use (expr
);
6789 if (TREE_CODE (type
) == REFERENCE_TYPE
)
6791 error ("cannot receive reference type %qT through %<...%>", type
);
6792 return error_mark_node
;
6795 if (type_has_nontrivial_copy_init (type
)
6796 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
6798 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
6799 it as pass by invisible reference. */
6800 warning_at (loc
, OPT_Wconditionally_supported
,
6801 "receiving objects of non-trivially-copyable type %q#T "
6802 "through %<...%> is conditionally-supported", type
);
6804 tree ref
= cp_build_reference_type (type
, false);
6805 expr
= build_va_arg (loc
, expr
, ref
);
6806 return convert_from_reference (expr
);
6809 return build_va_arg (loc
, expr
, type
);
6812 /* TYPE has been given to va_arg. Apply the default conversions which
6813 would have happened when passed via ellipsis. Return the promoted
6814 type, or the passed type if there is no change. */
6817 cxx_type_promotes_to (tree type
)
6821 /* Perform the array-to-pointer and function-to-pointer
6823 type
= type_decays_to (type
);
6825 promote
= type_promotes_to (type
);
6826 if (same_type_p (type
, promote
))
6832 /* ARG is a default argument expression being passed to a parameter of
6833 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6834 zero-based argument number. Do any required conversions. Return
6835 the converted value. */
6837 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
6839 push_defarg_context (tree fn
)
6840 { vec_safe_push (default_arg_context
, fn
); }
6843 pop_defarg_context (void)
6844 { default_arg_context
->pop (); }
6847 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
6848 tsubst_flags_t complain
)
6853 /* See through clones. */
6854 fn
= DECL_ORIGIN (fn
);
6856 /* Detect recursion. */
6857 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
6860 if (complain
& tf_error
)
6861 error ("recursive evaluation of default argument for %q#D", fn
);
6862 return error_mark_node
;
6865 /* If the ARG is an unparsed default argument expression, the
6866 conversion cannot be performed. */
6867 if (TREE_CODE (arg
) == DEFAULT_ARG
)
6869 if (complain
& tf_error
)
6870 error ("call to %qD uses the default argument for parameter %P, which "
6871 "is not yet defined", fn
, parmnum
);
6872 return error_mark_node
;
6875 push_defarg_context (fn
);
6877 if (fn
&& DECL_TEMPLATE_INFO (fn
))
6878 arg
= tsubst_default_argument (fn
, type
, arg
, complain
);
6884 The names in the expression are bound, and the semantic
6885 constraints are checked, at the point where the default
6886 expressions appears.
6888 we must not perform access checks here. */
6889 push_deferring_access_checks (dk_no_check
);
6890 /* We must make a copy of ARG, in case subsequent processing
6891 alters any part of it. */
6892 arg
= break_out_target_exprs (arg
);
6893 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
6894 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
6896 arg
= convert_for_arg_passing (type
, arg
, complain
);
6897 pop_deferring_access_checks();
6899 pop_defarg_context ();
6904 /* Returns the type which will really be used for passing an argument of
6908 type_passed_as (tree type
)
6910 /* Pass classes with copy ctors by invisible reference. */
6911 if (TREE_ADDRESSABLE (type
))
6913 type
= build_reference_type (type
);
6914 /* There are no other pointers to this temporary. */
6915 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
6917 else if (targetm
.calls
.promote_prototypes (type
)
6918 && INTEGRAL_TYPE_P (type
)
6919 && COMPLETE_TYPE_P (type
)
6920 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
6921 type
= integer_type_node
;
6926 /* Actually perform the appropriate conversion. */
6929 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
6933 /* If VAL is a bitfield, then -- since it has already been converted
6934 to TYPE -- it cannot have a precision greater than TYPE.
6936 If it has a smaller precision, we must widen it here. For
6937 example, passing "int f:3;" to a function expecting an "int" will
6938 not result in any conversion before this point.
6940 If the precision is the same we must not risk widening. For
6941 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6942 often have type "int", even though the C++ type for the field is
6943 "long long". If the value is being passed to a function
6944 expecting an "int", then no conversions will be required. But,
6945 if we call convert_bitfield_to_declared_type, the bitfield will
6946 be converted to "long long". */
6947 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
6949 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
6950 val
= convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type
), val
);
6952 if (val
== error_mark_node
)
6954 /* Pass classes with copy ctors by invisible reference. */
6955 else if (TREE_ADDRESSABLE (type
))
6956 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
6957 else if (targetm
.calls
.promote_prototypes (type
)
6958 && INTEGRAL_TYPE_P (type
)
6959 && COMPLETE_TYPE_P (type
)
6960 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
6961 val
= cp_perform_integral_promotions (val
, complain
);
6962 if ((complain
& tf_warning
)
6963 && warn_suggest_attribute_format
)
6965 tree rhstype
= TREE_TYPE (val
);
6966 const enum tree_code coder
= TREE_CODE (rhstype
);
6967 const enum tree_code codel
= TREE_CODE (type
);
6968 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
6970 && check_missing_format_attribute (type
, rhstype
))
6971 warning (OPT_Wsuggest_attribute_format
,
6972 "argument of function call might be a candidate for a format attribute");
6977 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6978 which no conversions at all should be done. This is true for some
6979 builtins which don't act like normal functions. */
6982 magic_varargs_p (tree fn
)
6984 if (flag_cilkplus
&& is_cilkplus_reduce_builtin (fn
) != BUILT_IN_NONE
)
6987 if (DECL_BUILT_IN (fn
))
6988 switch (DECL_FUNCTION_CODE (fn
))
6990 case BUILT_IN_CLASSIFY_TYPE
:
6991 case BUILT_IN_CONSTANT_P
:
6992 case BUILT_IN_NEXT_ARG
:
6993 case BUILT_IN_VA_START
:
6997 return lookup_attribute ("type generic",
6998 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7004 /* Returns the decl of the dispatcher function if FN is a function version. */
7007 get_function_version_dispatcher (tree fn
)
7009 tree dispatcher_decl
= NULL
;
7011 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7012 && DECL_FUNCTION_VERSIONED (fn
));
7014 gcc_assert (targetm
.get_function_versions_dispatcher
);
7015 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7017 if (dispatcher_decl
== NULL
)
7019 error_at (input_location
, "use of multiversioned function "
7020 "without a default");
7024 retrofit_lang_decl (dispatcher_decl
);
7025 gcc_assert (dispatcher_decl
!= NULL
);
7026 return dispatcher_decl
;
7029 /* fn is a function version dispatcher that is marked used. Mark all the
7030 semantically identical function versions it will dispatch as used. */
7033 mark_versions_used (tree fn
)
7035 struct cgraph_node
*node
;
7036 struct cgraph_function_version_info
*node_v
;
7037 struct cgraph_function_version_info
*it_v
;
7039 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7041 node
= cgraph_node::get (fn
);
7045 gcc_assert (node
->dispatcher_function
);
7047 node_v
= node
->function_version ();
7051 /* All semantically identical versions are chained. Traverse and mark each
7052 one of them as used. */
7053 it_v
= node_v
->next
;
7054 while (it_v
!= NULL
)
7056 mark_used (it_v
->this_node
->decl
);
7061 /* Build a call to "the copy constructor" for the type of A, even if it
7062 wouldn't be selected by normal overload resolution. Used for
7066 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7068 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7069 tree binfo
= TYPE_BINFO (ctype
);
7070 tree copy
= get_copy_ctor (ctype
, complain
);
7071 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7072 tree ob
= build_dummy_object (ctype
);
7073 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7074 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7075 LOOKUP_NORMAL
, NULL
, complain
);
7076 release_tree_vector (args
);
7080 /* Subroutine of the various build_*_call functions. Overload resolution
7081 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7082 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7083 bitmask of various LOOKUP_* flags which apply to the call itself. */
7086 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7089 const vec
<tree
, va_gc
> *args
= cand
->args
;
7090 tree first_arg
= cand
->first_arg
;
7091 conversion
**convs
= cand
->convs
;
7093 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
7098 unsigned int arg_index
= 0;
7102 bool already_used
= false;
7104 /* In a template, there is no need to perform all of the work that
7105 is normally done. We are only interested in the type of the call
7106 expression, i.e., the return type of the function. Any semantic
7107 errors will be deferred until the template is instantiated. */
7108 if (processing_template_decl
)
7112 const tree
*argarray
;
7115 return_type
= TREE_TYPE (TREE_TYPE (fn
));
7116 nargs
= vec_safe_length (args
);
7117 if (first_arg
== NULL_TREE
)
7118 argarray
= args
->address ();
7126 alcarray
= XALLOCAVEC (tree
, nargs
);
7127 alcarray
[0] = build_this (first_arg
);
7128 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
7129 alcarray
[ix
+ 1] = arg
;
7130 argarray
= alcarray
;
7133 addr
= build_addr_func (fn
, complain
);
7134 if (addr
== error_mark_node
)
7135 return error_mark_node
;
7136 expr
= build_call_array_loc (input_location
, return_type
,
7137 addr
, nargs
, argarray
);
7138 if (TREE_THIS_VOLATILE (fn
) && cfun
)
7139 current_function_returns_abnormally
= 1;
7140 return convert_from_reference (expr
);
7143 /* Give any warnings we noticed during overload resolution. */
7144 if (cand
->warnings
&& (complain
& tf_warning
))
7146 struct candidate_warning
*w
;
7147 for (w
= cand
->warnings
; w
; w
= w
->next
)
7148 joust (cand
, w
->loser
, 1, complain
);
7151 /* Make =delete work with SFINAE. */
7152 if (DECL_DELETED_FN (fn
) && !(complain
& tf_error
))
7153 return error_mark_node
;
7155 if (DECL_FUNCTION_MEMBER_P (fn
))
7158 /* If FN is a template function, two cases must be considered.
7163 template <class T> void f();
7165 template <class T> struct B {
7169 struct C : A, B<int> {
7171 using B<int>::g; // #2
7174 In case #1 where `A::f' is a member template, DECL_ACCESS is
7175 recorded in the primary template but not in its specialization.
7176 We check access of FN using its primary template.
7178 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7179 because it is a member of class template B, DECL_ACCESS is
7180 recorded in the specialization `B<int>::g'. We cannot use its
7181 primary template because `B<T>::g' and `B<int>::g' may have
7182 different access. */
7183 if (DECL_TEMPLATE_INFO (fn
)
7184 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
7185 access_fn
= DECL_TI_TEMPLATE (fn
);
7188 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
7190 return error_mark_node
;
7193 /* If we're checking for implicit delete, don't bother with argument
7195 if (flags
& LOOKUP_SPECULATIVE
)
7197 if (DECL_DELETED_FN (fn
))
7199 if (complain
& tf_error
)
7201 return error_mark_node
;
7203 if (cand
->viable
== 1)
7205 else if (!(complain
& tf_error
))
7206 /* Reject bad conversions now. */
7207 return error_mark_node
;
7208 /* else continue to get conversion error. */
7211 /* N3276 magic doesn't apply to nested calls. */
7212 int decltype_flag
= (complain
& tf_decltype
);
7213 complain
&= ~tf_decltype
;
7215 /* Find maximum size of vector to hold converted arguments. */
7216 parmlen
= list_length (parm
);
7217 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
7218 if (parmlen
> nargs
)
7220 argarray
= XALLOCAVEC (tree
, nargs
);
7222 /* The implicit parameters to a constructor are not considered by overload
7223 resolution, and must be of the proper type. */
7224 if (DECL_CONSTRUCTOR_P (fn
))
7227 if (first_arg
!= NULL_TREE
)
7229 object_arg
= first_arg
;
7230 first_arg
= NULL_TREE
;
7234 object_arg
= (*args
)[arg_index
];
7237 argarray
[j
++] = build_this (object_arg
);
7238 parm
= TREE_CHAIN (parm
);
7239 /* We should never try to call the abstract constructor. */
7240 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
7242 if (DECL_HAS_VTT_PARM_P (fn
))
7244 argarray
[j
++] = (*args
)[arg_index
];
7246 parm
= TREE_CHAIN (parm
);
7249 /* Bypass access control for 'this' parameter. */
7250 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
7252 tree parmtype
= TREE_VALUE (parm
);
7253 tree arg
= build_this (first_arg
!= NULL_TREE
7255 : (*args
)[arg_index
]);
7256 tree argtype
= TREE_TYPE (arg
);
7260 if (convs
[i
]->bad_p
)
7262 if (complain
& tf_error
)
7264 if (permerror (input_location
, "passing %qT as %<this%> "
7265 "argument discards qualifiers",
7266 TREE_TYPE (argtype
)))
7267 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
7270 return error_mark_node
;
7273 /* See if the function member or the whole class type is declared
7274 final and the call can be devirtualized. */
7275 if (DECL_FINAL_P (fn
)
7276 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
7277 flags
|= LOOKUP_NONVIRTUAL
;
7279 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
7280 X is called for an object that is not of type X, or of a type
7281 derived from X, the behavior is undefined.
7283 So we can assume that anything passed as 'this' is non-null, and
7284 optimize accordingly. */
7285 gcc_assert (TYPE_PTR_P (parmtype
));
7286 /* Convert to the base in which the function was declared. */
7287 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
7288 converted_arg
= build_base_path (PLUS_EXPR
,
7290 cand
->conversion_path
,
7292 /* Check that the base class is accessible. */
7293 if (!accessible_base_p (TREE_TYPE (argtype
),
7294 BINFO_TYPE (cand
->conversion_path
), true))
7296 if (complain
& tf_error
)
7297 error ("%qT is not an accessible base of %qT",
7298 BINFO_TYPE (cand
->conversion_path
),
7299 TREE_TYPE (argtype
));
7301 return error_mark_node
;
7303 /* If fn was found by a using declaration, the conversion path
7304 will be to the derived class, not the base declaring fn. We
7305 must convert from derived to base. */
7306 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
7307 TREE_TYPE (parmtype
), ba_unique
,
7309 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
7310 base_binfo
, 1, complain
);
7312 argarray
[j
++] = converted_arg
;
7313 parm
= TREE_CHAIN (parm
);
7314 if (first_arg
!= NULL_TREE
)
7315 first_arg
= NULL_TREE
;
7322 gcc_assert (first_arg
== NULL_TREE
);
7323 for (; arg_index
< vec_safe_length (args
) && parm
;
7324 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
7326 tree type
= TREE_VALUE (parm
);
7327 tree arg
= (*args
)[arg_index
];
7328 bool conversion_warning
= true;
7332 /* If the argument is NULL and used to (implicitly) instantiate a
7333 template function (and bind one of the template arguments to
7334 the type of 'long int'), we don't want to warn about passing NULL
7335 to non-pointer argument.
7336 For example, if we have this template function:
7338 template<typename T> void func(T x) {}
7340 we want to warn (when -Wconversion is enabled) in this case:
7346 but not in this case:
7352 if (arg
== null_node
7353 && DECL_TEMPLATE_INFO (fn
)
7354 && cand
->template_decl
7355 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
7356 conversion_warning
= false;
7358 /* Warn about initializer_list deduction that isn't currently in the
7360 if (cxx_dialect
> cxx98
7361 && flag_deduce_init_list
7362 && cand
->template_decl
7363 && is_std_init_list (non_reference (type
))
7364 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
7366 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
7367 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
7368 tree patparm
= get_pattern_parm (realparm
, tmpl
);
7369 tree pattype
= TREE_TYPE (patparm
);
7370 if (PACK_EXPANSION_P (pattype
))
7371 pattype
= PACK_EXPANSION_PATTERN (pattype
);
7372 pattype
= non_reference (pattype
);
7374 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
7375 && (cand
->explicit_targs
== NULL_TREE
7376 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
7377 <= TEMPLATE_TYPE_IDX (pattype
))))
7379 pedwarn (input_location
, 0, "deducing %qT as %qT",
7380 non_reference (TREE_TYPE (patparm
)),
7381 non_reference (type
));
7382 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
7383 " in call to %qD", cand
->fn
);
7384 pedwarn (input_location
, 0,
7385 " (you can disable this with -fno-deduce-init-list)");
7388 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
7391 : complain
& (~tf_warning
));
7393 val
= convert_for_arg_passing (type
, val
, complain
);
7395 if (val
== error_mark_node
)
7396 return error_mark_node
;
7398 argarray
[j
++] = val
;
7401 /* Default arguments */
7402 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
7404 if (TREE_VALUE (parm
) == error_mark_node
)
7405 return error_mark_node
;
7406 argarray
[j
++] = convert_default_arg (TREE_VALUE (parm
),
7407 TREE_PURPOSE (parm
),
7413 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
7415 tree a
= (*args
)[arg_index
];
7416 if (magic_varargs_p (fn
))
7417 /* Do no conversions for magic varargs. */
7418 a
= mark_type_use (a
);
7419 else if (DECL_CONSTRUCTOR_P (fn
)
7420 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
7423 /* Avoid infinite recursion trying to call A(...). */
7424 if (complain
& tf_error
)
7425 /* Try to call the actual copy constructor for a good error. */
7426 call_copy_ctor (a
, complain
);
7427 return error_mark_node
;
7430 a
= convert_arg_to_ellipsis (a
, complain
);
7434 gcc_assert (j
<= nargs
);
7437 check_function_arguments (TREE_TYPE (fn
), nargs
, argarray
);
7439 /* Avoid actually calling copy constructors and copy assignment operators,
7442 if (! flag_elide_constructors
)
7443 /* Do things the hard way. */;
7444 else if (cand
->num_convs
== 1
7445 && (DECL_COPY_CONSTRUCTOR_P (fn
)
7446 || DECL_MOVE_CONSTRUCTOR_P (fn
))
7447 /* It's unsafe to elide the constructor when handling
7448 a noexcept-expression, it may evaluate to the wrong
7449 value (c++/53025). */
7450 && cp_noexcept_operand
== 0)
7453 tree arg
= argarray
[num_artificial_parms_for (fn
)];
7455 bool trivial
= trivial_fn_p (fn
);
7457 /* Pull out the real argument, disregarding const-correctness. */
7459 while (CONVERT_EXPR_P (targ
)
7460 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
7461 targ
= TREE_OPERAND (targ
, 0);
7462 if (TREE_CODE (targ
) == ADDR_EXPR
)
7464 targ
= TREE_OPERAND (targ
, 0);
7465 if (!same_type_ignoring_top_level_qualifiers_p
7466 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
7475 arg
= cp_build_indirect_ref (arg
, RO_NULL
, complain
);
7477 /* [class.copy]: the copy constructor is implicitly defined even if
7478 the implementation elided its use. */
7479 if (!trivial
|| DECL_DELETED_FN (fn
))
7481 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
7482 return error_mark_node
;
7483 already_used
= true;
7486 /* If we're creating a temp and we already have one, don't create a
7487 new one. If we're not creating a temp but we get one, use
7488 INIT_EXPR to collapse the temp into our target. Otherwise, if the
7489 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
7490 temp or an INIT_EXPR otherwise. */
7492 if (is_dummy_object (fa
))
7494 if (TREE_CODE (arg
) == TARGET_EXPR
)
7497 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
7499 else if (TREE_CODE (arg
) == TARGET_EXPR
|| trivial
)
7501 tree to
= stabilize_reference (cp_build_indirect_ref (fa
, RO_NULL
,
7504 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
7508 else if (DECL_OVERLOADED_OPERATOR_P (fn
) == NOP_EXPR
7509 && trivial_fn_p (fn
)
7510 && !DECL_DELETED_FN (fn
))
7512 tree to
= stabilize_reference
7513 (cp_build_indirect_ref (argarray
[0], RO_NULL
, complain
));
7514 tree type
= TREE_TYPE (to
);
7515 tree as_base
= CLASSTYPE_AS_BASE (type
);
7516 tree arg
= argarray
[1];
7518 if (is_really_empty_class (type
))
7520 /* Avoid copying empty classes. */
7521 val
= build2 (COMPOUND_EXPR
, void_type_node
, to
, arg
);
7522 TREE_NO_WARNING (val
) = 1;
7523 val
= build2 (COMPOUND_EXPR
, type
, val
, to
);
7524 TREE_NO_WARNING (val
) = 1;
7526 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
7528 arg
= cp_build_indirect_ref (arg
, RO_NULL
, complain
);
7529 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
7533 /* We must only copy the non-tail padding parts. */
7535 tree array_type
, alias_set
;
7537 arg2
= TYPE_SIZE_UNIT (as_base
);
7538 arg0
= cp_build_addr_expr (to
, complain
);
7540 array_type
= build_array_type (char_type_node
,
7542 (size_binop (MINUS_EXPR
,
7543 arg2
, size_int (1))));
7544 alias_set
= build_int_cst (build_pointer_type (type
), 0);
7545 t
= build2 (MODIFY_EXPR
, void_type_node
,
7546 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
7547 build2 (MEM_REF
, array_type
, arg
, alias_set
));
7548 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
7549 TREE_NO_WARNING (val
) = 1;
7554 else if (DECL_DESTRUCTOR_P (fn
)
7555 && trivial_fn_p (fn
)
7556 && !DECL_DELETED_FN (fn
))
7557 return fold_convert (void_type_node
, argarray
[0]);
7558 /* FIXME handle trivial default constructor, too. */
7560 /* For calls to a multi-versioned function, overload resolution
7561 returns the function with the highest target priority, that is,
7562 the version that will checked for dispatching first. If this
7563 version is inlinable, a direct call to this version can be made
7564 otherwise the call should go through the dispatcher. */
7566 if (DECL_FUNCTION_VERSIONED (fn
)
7567 && (current_function_decl
== NULL
7568 || !targetm
.target_option
.can_inline_p (current_function_decl
, fn
)))
7570 fn
= get_function_version_dispatcher (fn
);
7574 mark_versions_used (fn
);
7578 && !mark_used (fn
, complain
))
7579 return error_mark_node
;
7581 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0
7582 /* Don't mess with virtual lookup in instantiate_non_dependent_expr;
7583 virtual functions can't be constexpr. */
7584 && !in_template_function ())
7587 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
7589 ba_any
, NULL
, complain
);
7590 gcc_assert (binfo
&& binfo
!= error_mark_node
);
7592 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
7594 if (TREE_SIDE_EFFECTS (argarray
[0]))
7595 argarray
[0] = save_expr (argarray
[0]);
7596 t
= build_pointer_type (TREE_TYPE (fn
));
7597 if (DECL_CONTEXT (fn
) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn
)))
7598 fn
= build_java_interface_fn_ref (fn
, argarray
[0]);
7600 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
7605 fn
= build_addr_func (fn
, complain
);
7606 if (fn
== error_mark_node
)
7607 return error_mark_node
;
7610 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
7611 if (TREE_CODE (call
) == CALL_EXPR
7612 && (cand
->flags
& LOOKUP_LIST_INIT_CTOR
))
7613 CALL_EXPR_LIST_INIT_P (call
) = true;
7617 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
7618 This function performs no overload resolution, conversion, or other
7619 high-level operations. */
7622 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
7623 tsubst_flags_t complain
)
7628 /* Remember roughly where this call is. */
7629 location_t loc
= EXPR_LOC_OR_LOC (fn
, input_location
);
7630 fn
= build_call_a (fn
, nargs
, argarray
);
7631 SET_EXPR_LOCATION (fn
, loc
);
7633 fndecl
= get_callee_fndecl (fn
);
7635 /* Check that arguments to builtin functions match the expectations. */
7637 && DECL_BUILT_IN (fndecl
)
7638 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
7639 && !check_builtin_function_arguments (fndecl
, nargs
, argarray
))
7640 return error_mark_node
;
7642 /* If it is a built-in array notation function, then the return type of
7643 the function is the element type of the array passed in as array
7644 notation (i.e. the first parameter of the function). */
7645 if (flag_cilkplus
&& TREE_CODE (fn
) == CALL_EXPR
)
7647 enum built_in_function bif
=
7648 is_cilkplus_reduce_builtin (CALL_EXPR_FN (fn
));
7649 if (bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_ADD
7650 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MUL
7651 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MAX
7652 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MIN
7653 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE
7654 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MUTATING
)
7656 if (call_expr_nargs (fn
) == 0)
7658 error_at (EXPR_LOCATION (fn
), "Invalid builtin arguments");
7659 return error_mark_node
;
7661 /* for bif == BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_ZERO or
7662 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_ZERO or
7663 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_NONZERO or
7664 BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_NONZERO or
7665 BUILT_IN_CILKPLUS_SEC_REDUCE_MIN_IND or
7666 BUILT_IN_CILKPLUS_SEC_REDUCE_MAX_IND
7667 The pre-defined return-type is the correct one. */
7668 tree array_ntn
= CALL_EXPR_ARG (fn
, 0);
7669 TREE_TYPE (fn
) = TREE_TYPE (array_ntn
);
7674 /* Some built-in function calls will be evaluated at compile-time in
7675 fold (). Set optimize to 1 when folding __builtin_constant_p inside
7676 a constexpr function so that fold_builtin_1 doesn't fold it to 0. */
7677 optimize_sav
= optimize
;
7678 if (!optimize
&& fndecl
&& DECL_IS_BUILTIN_CONSTANT_P (fndecl
)
7679 && current_function_decl
7680 && DECL_DECLARED_CONSTEXPR_P (current_function_decl
))
7682 fn
= fold_if_not_in_template (fn
);
7683 optimize
= optimize_sav
;
7685 if (VOID_TYPE_P (TREE_TYPE (fn
)))
7688 /* 5.2.2/11: If a function call is a prvalue of object type: if the
7689 function call is either the operand of a decltype-specifier or the
7690 right operand of a comma operator that is the operand of a
7691 decltype-specifier, a temporary object is not introduced for the
7692 prvalue. The type of the prvalue may be incomplete. */
7693 if (!(complain
& tf_decltype
))
7695 fn
= require_complete_type_sfinae (fn
, complain
);
7696 if (fn
== error_mark_node
)
7697 return error_mark_node
;
7699 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
7700 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
7702 return convert_from_reference (fn
);
7705 static GTY(()) tree java_iface_lookup_fn
;
7707 /* Make an expression which yields the address of the Java interface
7708 method FN. This is achieved by generating a call to libjava's
7709 _Jv_LookupInterfaceMethodIdx(). */
7712 build_java_interface_fn_ref (tree fn
, tree instance
)
7714 tree lookup_fn
, method
, idx
;
7715 tree klass_ref
, iface
, iface_ref
;
7718 if (!java_iface_lookup_fn
)
7720 tree ftype
= build_function_type_list (ptr_type_node
,
7721 ptr_type_node
, ptr_type_node
,
7722 java_int_type_node
, NULL_TREE
);
7723 java_iface_lookup_fn
7724 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype
,
7725 0, NOT_BUILT_IN
, NULL
, NULL_TREE
);
7728 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
7729 This is the first entry in the vtable. */
7730 klass_ref
= build_vtbl_ref (cp_build_indirect_ref (instance
, RO_NULL
,
7731 tf_warning_or_error
),
7734 /* Get the java.lang.Class pointer for the interface being called. */
7735 iface
= DECL_CONTEXT (fn
);
7736 iface_ref
= lookup_field (iface
, get_identifier ("class$"), 0, false);
7737 if (!iface_ref
|| !VAR_P (iface_ref
)
7738 || DECL_CONTEXT (iface_ref
) != iface
)
7740 error ("could not find class$ field in java interface type %qT",
7742 return error_mark_node
;
7744 iface_ref
= build_address (iface_ref
);
7745 iface_ref
= convert (build_pointer_type (iface
), iface_ref
);
7747 /* Determine the itable index of FN. */
7749 for (method
= TYPE_METHODS (iface
); method
; method
= DECL_CHAIN (method
))
7751 if (!DECL_VIRTUAL_P (method
))
7757 idx
= build_int_cst (NULL_TREE
, i
);
7759 lookup_fn
= build1 (ADDR_EXPR
,
7760 build_pointer_type (TREE_TYPE (java_iface_lookup_fn
)),
7761 java_iface_lookup_fn
);
7762 return build_call_nary (ptr_type_node
, lookup_fn
,
7763 3, klass_ref
, iface_ref
, idx
);
7766 /* Returns the value to use for the in-charge parameter when making a
7767 call to a function with the indicated NAME.
7769 FIXME:Can't we find a neater way to do this mapping? */
7772 in_charge_arg_for_name (tree name
)
7774 if (name
== base_ctor_identifier
7775 || name
== base_dtor_identifier
)
7776 return integer_zero_node
;
7777 else if (name
== complete_ctor_identifier
)
7778 return integer_one_node
;
7779 else if (name
== complete_dtor_identifier
)
7780 return integer_two_node
;
7781 else if (name
== deleting_dtor_identifier
)
7782 return integer_three_node
;
7784 /* This function should only be called with one of the names listed
7790 /* Build a call to a constructor, destructor, or an assignment
7791 operator for INSTANCE, an expression with class type. NAME
7792 indicates the special member function to call; *ARGS are the
7793 arguments. ARGS may be NULL. This may change ARGS. BINFO
7794 indicates the base of INSTANCE that is to be passed as the `this'
7795 parameter to the member function called.
7797 FLAGS are the LOOKUP_* flags to use when processing the call.
7799 If NAME indicates a complete object constructor, INSTANCE may be
7800 NULL_TREE. In this case, the caller will call build_cplus_new to
7801 store the newly constructed object into a VAR_DECL. */
7804 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
7805 tree binfo
, int flags
, tsubst_flags_t complain
)
7808 /* The type of the subobject to be constructed or destroyed. */
7810 vec
<tree
, va_gc
> *allocated
= NULL
;
7813 gcc_assert (name
== complete_ctor_identifier
7814 || name
== base_ctor_identifier
7815 || name
== complete_dtor_identifier
7816 || name
== base_dtor_identifier
7817 || name
== deleting_dtor_identifier
7818 || name
== ansi_assopname (NOP_EXPR
));
7821 /* Resolve the name. */
7822 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
7823 return error_mark_node
;
7825 binfo
= TYPE_BINFO (binfo
);
7828 gcc_assert (binfo
!= NULL_TREE
);
7830 class_type
= BINFO_TYPE (binfo
);
7832 /* Handle the special case where INSTANCE is NULL_TREE. */
7833 if (name
== complete_ctor_identifier
&& !instance
)
7834 instance
= build_dummy_object (class_type
);
7837 if (name
== complete_dtor_identifier
7838 || name
== base_dtor_identifier
7839 || name
== deleting_dtor_identifier
)
7840 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
7842 /* Convert to the base class, if necessary. */
7843 if (!same_type_ignoring_top_level_qualifiers_p
7844 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
7846 if (name
!= ansi_assopname (NOP_EXPR
))
7847 /* For constructors and destructors, either the base is
7848 non-virtual, or it is virtual but we are doing the
7849 conversion from a constructor or destructor for the
7850 complete object. In either case, we can convert
7852 instance
= convert_to_base_statically (instance
, binfo
);
7854 /* However, for assignment operators, we must convert
7855 dynamically if the base is virtual. */
7856 instance
= build_base_path (PLUS_EXPR
, instance
,
7857 binfo
, /*nonnull=*/1, complain
);
7861 gcc_assert (instance
!= NULL_TREE
);
7863 fns
= lookup_fnfields (binfo
, name
, 1);
7865 /* When making a call to a constructor or destructor for a subobject
7866 that uses virtual base classes, pass down a pointer to a VTT for
7868 if ((name
== base_ctor_identifier
7869 || name
== base_dtor_identifier
)
7870 && CLASSTYPE_VBASECLASSES (class_type
))
7875 /* If the current function is a complete object constructor
7876 or destructor, then we fetch the VTT directly.
7877 Otherwise, we look it up using the VTT we were given. */
7878 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
7879 vtt
= decay_conversion (vtt
, complain
);
7880 if (vtt
== error_mark_node
)
7881 return error_mark_node
;
7882 vtt
= build3 (COND_EXPR
, TREE_TYPE (vtt
),
7883 build2 (EQ_EXPR
, boolean_type_node
,
7884 current_in_charge_parm
, integer_zero_node
),
7887 if (BINFO_SUBVTT_INDEX (binfo
))
7888 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
7894 allocated
= make_tree_vector ();
7898 vec_safe_insert (*args
, 0, sub_vtt
);
7901 ret
= build_new_method_call (instance
, fns
, args
,
7902 TYPE_BINFO (BINFO_TYPE (binfo
)),
7906 if (allocated
!= NULL
)
7907 release_tree_vector (allocated
);
7909 if ((complain
& tf_error
)
7910 && (flags
& LOOKUP_DELEGATING_CONS
)
7911 && name
== complete_ctor_identifier
7912 && TREE_CODE (ret
) == CALL_EXPR
7913 && (DECL_ABSTRACT_ORIGIN (TREE_OPERAND (CALL_EXPR_FN (ret
), 0))
7914 == current_function_decl
))
7915 error ("constructor delegates to itself");
7920 /* Return the NAME, as a C string. The NAME indicates a function that
7921 is a member of TYPE. *FREE_P is set to true if the caller must
7922 free the memory returned.
7924 Rather than go through all of this, we should simply set the names
7925 of constructors and destructors appropriately, and dispense with
7926 ctor_identifier, dtor_identifier, etc. */
7929 name_as_c_string (tree name
, tree type
, bool *free_p
)
7933 /* Assume that we will not allocate memory. */
7935 /* Constructors and destructors are special. */
7936 if (IDENTIFIER_CTOR_OR_DTOR_P (name
))
7939 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
))));
7940 /* For a destructor, add the '~'. */
7941 if (name
== complete_dtor_identifier
7942 || name
== base_dtor_identifier
7943 || name
== deleting_dtor_identifier
)
7945 pretty_name
= concat ("~", pretty_name
, NULL
);
7946 /* Remember that we need to free the memory allocated. */
7950 else if (IDENTIFIER_TYPENAME_P (name
))
7952 pretty_name
= concat ("operator ",
7953 type_as_string_translate (TREE_TYPE (name
),
7954 TFF_PLAIN_IDENTIFIER
),
7956 /* Remember that we need to free the memory allocated. */
7960 pretty_name
= CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name
)));
7965 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
7966 be set, upon return, to the function called. ARGS may be NULL.
7967 This may change ARGS. */
7970 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
7971 tree conversion_path
, int flags
,
7972 tree
*fn_p
, tsubst_flags_t complain
)
7974 struct z_candidate
*candidates
= 0, *cand
;
7975 tree explicit_targs
= NULL_TREE
;
7976 tree basetype
= NULL_TREE
;
7977 tree access_binfo
, binfo
;
7979 tree first_mem_arg
= NULL_TREE
;
7981 bool skip_first_for_error
;
7982 vec
<tree
, va_gc
> *user_args
;
7985 int template_only
= 0;
7989 vec
<tree
, va_gc
> *orig_args
= NULL
;
7992 gcc_assert (instance
!= NULL_TREE
);
7994 /* We don't know what function we're going to call, yet. */
7998 if (error_operand_p (instance
)
7999 || !fns
|| error_operand_p (fns
))
8000 return error_mark_node
;
8002 if (!BASELINK_P (fns
))
8004 if (complain
& tf_error
)
8005 error ("call to non-function %qD", fns
);
8006 return error_mark_node
;
8009 orig_instance
= instance
;
8012 /* Dismantle the baselink to collect all the information we need. */
8013 if (!conversion_path
)
8014 conversion_path
= BASELINK_BINFO (fns
);
8015 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
8016 binfo
= BASELINK_BINFO (fns
);
8017 optype
= BASELINK_OPTYPE (fns
);
8018 fns
= BASELINK_FUNCTIONS (fns
);
8019 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
8021 explicit_targs
= TREE_OPERAND (fns
, 1);
8022 fns
= TREE_OPERAND (fns
, 0);
8025 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
8026 || TREE_CODE (fns
) == TEMPLATE_DECL
8027 || TREE_CODE (fns
) == OVERLOAD
);
8028 fn
= get_first_fn (fns
);
8029 name
= DECL_NAME (fn
);
8031 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
8032 gcc_assert (CLASS_TYPE_P (basetype
));
8034 if (processing_template_decl
)
8036 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
8037 instance
= build_non_dependent_expr (instance
);
8039 make_args_non_dependent (*args
);
8042 user_args
= args
== NULL
? NULL
: *args
;
8043 /* Under DR 147 A::A() is an invalid constructor call,
8044 not a functional cast. */
8045 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
8047 if (! (complain
& tf_error
))
8048 return error_mark_node
;
8050 if (permerror (input_location
,
8051 "cannot call constructor %<%T::%D%> directly",
8053 inform (input_location
, "for a function-style cast, remove the "
8054 "redundant %<::%D%>", name
);
8055 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
8060 /* Figure out whether to skip the first argument for the error
8061 message we will display to users if an error occurs. We don't
8062 want to display any compiler-generated arguments. The "this"
8063 pointer hasn't been added yet. However, we must remove the VTT
8064 pointer if this is a call to a base-class constructor or
8066 skip_first_for_error
= false;
8067 if (IDENTIFIER_CTOR_OR_DTOR_P (name
))
8069 /* Callers should explicitly indicate whether they want to construct
8070 the complete object or just the part without virtual bases. */
8071 gcc_assert (name
!= ctor_identifier
);
8072 /* Similarly for destructors. */
8073 gcc_assert (name
!= dtor_identifier
);
8074 /* Remove the VTT pointer, if present. */
8075 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
8076 && CLASSTYPE_VBASECLASSES (basetype
))
8077 skip_first_for_error
= true;
8080 /* Process the argument list. */
8081 if (args
!= NULL
&& *args
!= NULL
)
8083 *args
= resolve_args (*args
, complain
);
8085 return error_mark_node
;
8088 /* Consider the object argument to be used even if we end up selecting a
8089 static member function. */
8090 instance
= mark_type_use (instance
);
8092 /* It's OK to call destructors and constructors on cv-qualified objects.
8093 Therefore, convert the INSTANCE to the unqualified type, if
8095 if (DECL_DESTRUCTOR_P (fn
)
8096 || DECL_CONSTRUCTOR_P (fn
))
8098 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
8100 instance
= build_this (instance
);
8101 instance
= build_nop (build_pointer_type (basetype
), instance
);
8102 instance
= build_fold_indirect_ref (instance
);
8105 if (DECL_DESTRUCTOR_P (fn
))
8106 name
= complete_dtor_identifier
;
8108 /* For the overload resolution we need to find the actual `this`
8109 that would be captured if the call turns out to be to a
8110 non-static member function. Do not actually capture it at this
8112 if (DECL_CONSTRUCTOR_P (fn
))
8113 /* Constructors don't use the enclosing 'this'. */
8114 first_mem_arg
= instance
;
8116 first_mem_arg
= maybe_resolve_dummy (instance
, false);
8118 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8119 p
= conversion_obstack_alloc (0);
8121 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
8122 initializer, not T({ }). */
8123 if (DECL_CONSTRUCTOR_P (fn
) && args
!= NULL
&& !vec_safe_is_empty (*args
)
8124 && DIRECT_LIST_INIT_P ((**args
)[0]))
8126 tree init_list
= (**args
)[0];
8127 tree init
= NULL_TREE
;
8129 gcc_assert ((*args
)->length () == 1
8130 && !(flags
& LOOKUP_ONLYCONVERTING
));
8132 /* If the initializer list has no elements and T is a class type with
8133 a default constructor, the object is value-initialized. Handle
8134 this here so we don't need to handle it wherever we use
8135 build_special_member_call. */
8136 if (CONSTRUCTOR_NELTS (init_list
) == 0
8137 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
8138 /* For a user-provided default constructor, use the normal
8139 mechanisms so that protected access works. */
8140 && type_has_non_user_provided_default_constructor (basetype
)
8141 && !processing_template_decl
)
8142 init
= build_value_init (basetype
, complain
);
8144 /* If BASETYPE is an aggregate, we need to do aggregate
8146 else if (CP_AGGREGATE_TYPE_P (basetype
))
8148 init
= reshape_init (basetype
, init_list
, complain
);
8149 init
= digest_init (basetype
, init
, complain
);
8154 if (is_dummy_object (instance
))
8155 return get_target_expr_sfinae (init
, complain
);
8156 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
8157 TREE_SIDE_EFFECTS (init
) = true;
8161 /* Otherwise go ahead with overload resolution. */
8162 add_list_candidates (fns
, first_mem_arg
, init_list
,
8163 basetype
, explicit_targs
, template_only
,
8164 conversion_path
, access_binfo
, flags
,
8165 &candidates
, complain
);
8169 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
8170 explicit_targs
, template_only
, conversion_path
,
8171 access_binfo
, flags
, &candidates
, complain
);
8173 any_viable_p
= false;
8174 candidates
= splice_viable (candidates
, false, &any_viable_p
);
8178 if (complain
& tf_error
)
8180 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
8181 cxx_incomplete_type_error (instance
, basetype
);
8183 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
8184 basetype
, optype
, build_tree_list_vec (user_args
),
8185 TREE_TYPE (instance
));
8192 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
8193 arglist
= build_tree_list_vec (user_args
);
8194 if (skip_first_for_error
)
8195 arglist
= TREE_CHAIN (arglist
);
8196 error ("no matching function for call to %<%T::%s(%A)%#V%>",
8197 basetype
, pretty_name
, arglist
,
8198 TREE_TYPE (instance
));
8202 print_z_candidates (location_of (name
), candidates
);
8204 call
= error_mark_node
;
8208 cand
= tourney (candidates
, complain
);
8215 if (complain
& tf_error
)
8217 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
8218 arglist
= build_tree_list_vec (user_args
);
8219 if (skip_first_for_error
)
8220 arglist
= TREE_CHAIN (arglist
);
8221 if (!any_strictly_viable (candidates
))
8222 error ("no matching function for call to %<%s(%A)%>",
8223 pretty_name
, arglist
);
8225 error ("call of overloaded %<%s(%A)%> is ambiguous",
8226 pretty_name
, arglist
);
8227 print_z_candidates (location_of (name
), candidates
);
8231 call
= error_mark_node
;
8238 if (!(flags
& LOOKUP_NONVIRTUAL
)
8239 && DECL_PURE_VIRTUAL_P (fn
)
8240 && instance
== current_class_ref
8241 && (complain
& tf_warning
))
8243 /* This is not an error, it is runtime undefined
8245 if (!current_function_decl
)
8246 warning (0, "pure virtual %q#D called from "
8247 "non-static data member initializer", fn
);
8248 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
8249 || DECL_DESTRUCTOR_P (current_function_decl
))
8250 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
8251 ? "pure virtual %q#D called from constructor"
8252 : "pure virtual %q#D called from destructor"),
8256 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
8257 && !DECL_CONSTRUCTOR_P (fn
)
8258 && is_dummy_object (instance
))
8260 instance
= maybe_resolve_dummy (instance
, true);
8261 if (instance
== error_mark_node
)
8262 call
= error_mark_node
;
8263 else if (!is_dummy_object (instance
))
8265 /* We captured 'this' in the current lambda now that
8266 we know we really need it. */
8267 cand
->first_arg
= instance
;
8271 if (complain
& tf_error
)
8272 error ("cannot call member function %qD without object",
8274 call
= error_mark_node
;
8278 if (call
!= error_mark_node
)
8280 /* Optimize away vtable lookup if we know that this
8281 function can't be overridden. We need to check if
8282 the context and the type where we found fn are the same,
8283 actually FN might be defined in a different class
8284 type because of a using-declaration. In this case, we
8285 do not want to perform a non-virtual call. */
8286 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
8287 && same_type_ignoring_top_level_qualifiers_p
8288 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
8289 && resolves_to_fixed_type_p (instance
, 0))
8290 flags
|= LOOKUP_NONVIRTUAL
;
8292 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
8293 /* Now we know what function is being called. */
8296 /* Build the actual CALL_EXPR. */
8297 call
= build_over_call (cand
, flags
, complain
);
8298 /* In an expression of the form `a->f()' where `f' turns
8299 out to be a static member function, `a' is
8300 none-the-less evaluated. */
8301 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
8302 && !is_dummy_object (instance
)
8303 && TREE_SIDE_EFFECTS (instance
))
8304 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
),
8306 else if (call
!= error_mark_node
8307 && DECL_DESTRUCTOR_P (cand
->fn
)
8308 && !VOID_TYPE_P (TREE_TYPE (call
)))
8309 /* An explicit call of the form "x->~X()" has type
8310 "void". However, on platforms where destructors
8311 return "this" (i.e., those where
8312 targetm.cxx.cdtor_returns_this is true), such calls
8313 will appear to have a return value of pointer type
8314 to the low-level call machinery. We do not want to
8315 change the low-level machinery, since we want to be
8316 able to optimize "delete f()" on such platforms as
8317 "operator delete(~X(f()))" (rather than generating
8318 "t = f(), ~X(t), operator delete (t)"). */
8319 call
= build_nop (void_type_node
, call
);
8324 if (processing_template_decl
&& call
!= error_mark_node
)
8326 bool cast_to_void
= false;
8328 if (TREE_CODE (call
) == COMPOUND_EXPR
)
8329 call
= TREE_OPERAND (call
, 1);
8330 else if (TREE_CODE (call
) == NOP_EXPR
)
8332 cast_to_void
= true;
8333 call
= TREE_OPERAND (call
, 0);
8335 if (INDIRECT_REF_P (call
))
8336 call
= TREE_OPERAND (call
, 0);
8337 call
= (build_min_non_dep_call_vec
8339 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
8340 orig_instance
, orig_fns
, NULL_TREE
),
8342 SET_EXPR_LOCATION (call
, input_location
);
8343 call
= convert_from_reference (call
);
8345 call
= build_nop (void_type_node
, call
);
8348 /* Free all the conversions we allocated. */
8349 obstack_free (&conversion_obstack
, p
);
8351 if (orig_args
!= NULL
)
8352 release_tree_vector (orig_args
);
8357 /* Wrapper for above. */
8360 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
8361 tree conversion_path
, int flags
,
8362 tree
*fn_p
, tsubst_flags_t complain
)
8365 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
8366 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
8368 timevar_cond_stop (TV_OVERLOAD
, subtime
);
8372 /* Returns true iff standard conversion sequence ICS1 is a proper
8373 subsequence of ICS2. */
8376 is_subseq (conversion
*ics1
, conversion
*ics2
)
8378 /* We can assume that a conversion of the same code
8379 between the same types indicates a subsequence since we only get
8380 here if the types we are converting from are the same. */
8382 while (ics1
->kind
== ck_rvalue
8383 || ics1
->kind
== ck_lvalue
)
8384 ics1
= next_conversion (ics1
);
8388 while (ics2
->kind
== ck_rvalue
8389 || ics2
->kind
== ck_lvalue
)
8390 ics2
= next_conversion (ics2
);
8392 if (ics2
->kind
== ck_user
8393 || ics2
->kind
== ck_ambig
8394 || ics2
->kind
== ck_aggr
8395 || ics2
->kind
== ck_list
8396 || ics2
->kind
== ck_identity
)
8397 /* At this point, ICS1 cannot be a proper subsequence of
8398 ICS2. We can get a USER_CONV when we are comparing the
8399 second standard conversion sequence of two user conversion
8403 ics2
= next_conversion (ics2
);
8405 if (ics2
->kind
== ics1
->kind
8406 && same_type_p (ics2
->type
, ics1
->type
)
8407 && same_type_p (next_conversion (ics2
)->type
,
8408 next_conversion (ics1
)->type
))
8413 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
8414 be any _TYPE nodes. */
8417 is_properly_derived_from (tree derived
, tree base
)
8419 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
8422 /* We only allow proper derivation here. The DERIVED_FROM_P macro
8423 considers every class derived from itself. */
8424 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
8425 && DERIVED_FROM_P (base
, derived
));
8428 /* We build the ICS for an implicit object parameter as a pointer
8429 conversion sequence. However, such a sequence should be compared
8430 as if it were a reference conversion sequence. If ICS is the
8431 implicit conversion sequence for an implicit object parameter,
8432 modify it accordingly. */
8435 maybe_handle_implicit_object (conversion
**ics
)
8439 /* [over.match.funcs]
8441 For non-static member functions, the type of the
8442 implicit object parameter is "reference to cv X"
8443 where X is the class of which the function is a
8444 member and cv is the cv-qualification on the member
8445 function declaration. */
8446 conversion
*t
= *ics
;
8447 tree reference_type
;
8449 /* The `this' parameter is a pointer to a class type. Make the
8450 implicit conversion talk about a reference to that same class
8452 reference_type
= TREE_TYPE (t
->type
);
8453 reference_type
= build_reference_type (reference_type
);
8455 if (t
->kind
== ck_qual
)
8456 t
= next_conversion (t
);
8457 if (t
->kind
== ck_ptr
)
8458 t
= next_conversion (t
);
8459 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
8460 t
= direct_reference_binding (reference_type
, t
);
8462 t
->rvaluedness_matches_p
= 0;
8467 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
8468 and return the initial reference binding conversion. Otherwise,
8469 leave *ICS unchanged and return NULL. */
8472 maybe_handle_ref_bind (conversion
**ics
)
8474 if ((*ics
)->kind
== ck_ref_bind
)
8476 conversion
*old_ics
= *ics
;
8477 *ics
= next_conversion (old_ics
);
8478 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
8485 /* Compare two implicit conversion sequences according to the rules set out in
8486 [over.ics.rank]. Return values:
8488 1: ics1 is better than ics2
8489 -1: ics2 is better than ics1
8490 0: ics1 and ics2 are indistinguishable */
8493 compare_ics (conversion
*ics1
, conversion
*ics2
)
8499 tree deref_from_type1
= NULL_TREE
;
8500 tree deref_from_type2
= NULL_TREE
;
8501 tree deref_to_type1
= NULL_TREE
;
8502 tree deref_to_type2
= NULL_TREE
;
8503 conversion_rank rank1
, rank2
;
8505 /* REF_BINDING is nonzero if the result of the conversion sequence
8506 is a reference type. In that case REF_CONV is the reference
8507 binding conversion. */
8508 conversion
*ref_conv1
;
8509 conversion
*ref_conv2
;
8511 /* Compare badness before stripping the reference conversion. */
8512 if (ics1
->bad_p
> ics2
->bad_p
)
8514 else if (ics1
->bad_p
< ics2
->bad_p
)
8517 /* Handle implicit object parameters. */
8518 maybe_handle_implicit_object (&ics1
);
8519 maybe_handle_implicit_object (&ics2
);
8521 /* Handle reference parameters. */
8522 ref_conv1
= maybe_handle_ref_bind (&ics1
);
8523 ref_conv2
= maybe_handle_ref_bind (&ics2
);
8525 /* List-initialization sequence L1 is a better conversion sequence than
8526 list-initialization sequence L2 if L1 converts to
8527 std::initializer_list<X> for some X and L2 does not. */
8528 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
8530 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
8535 When comparing the basic forms of implicit conversion sequences (as
8536 defined in _over.best.ics_)
8538 --a standard conversion sequence (_over.ics.scs_) is a better
8539 conversion sequence than a user-defined conversion sequence
8540 or an ellipsis conversion sequence, and
8542 --a user-defined conversion sequence (_over.ics.user_) is a
8543 better conversion sequence than an ellipsis conversion sequence
8544 (_over.ics.ellipsis_). */
8545 /* Use BAD_CONVERSION_RANK because we already checked for a badness
8546 mismatch. If both ICS are bad, we try to make a decision based on
8547 what would have happened if they'd been good. This is not an
8548 extension, we'll still give an error when we build up the call; this
8549 just helps us give a more helpful error message. */
8550 rank1
= BAD_CONVERSION_RANK (ics1
);
8551 rank2
= BAD_CONVERSION_RANK (ics2
);
8555 else if (rank1
< rank2
)
8558 if (ics1
->ellipsis_p
)
8559 /* Both conversions are ellipsis conversions. */
8562 /* User-defined conversion sequence U1 is a better conversion sequence
8563 than another user-defined conversion sequence U2 if they contain the
8564 same user-defined conversion operator or constructor and if the sec-
8565 ond standard conversion sequence of U1 is better than the second
8566 standard conversion sequence of U2. */
8568 /* Handle list-conversion with the same code even though it isn't always
8569 ranked as a user-defined conversion and it doesn't have a second
8570 standard conversion sequence; it will still have the desired effect.
8571 Specifically, we need to do the reference binding comparison at the
8572 end of this function. */
8574 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
|| ics1
->kind
== ck_aggr
)
8579 for (t1
= ics1
; t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
8580 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
8581 || t1
->kind
== ck_list
)
8583 for (t2
= ics2
; t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
8584 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
8585 || t2
->kind
== ck_list
)
8588 if (t1
->kind
!= t2
->kind
)
8590 else if (t1
->kind
== ck_user
)
8592 if (t1
->cand
->fn
!= t2
->cand
->fn
)
8597 /* For ambiguous or aggregate conversions, use the target type as
8598 a proxy for the conversion function. */
8599 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
8603 /* We can just fall through here, after setting up
8604 FROM_TYPE1 and FROM_TYPE2. */
8605 from_type1
= t1
->type
;
8606 from_type2
= t2
->type
;
8613 /* We're dealing with two standard conversion sequences.
8617 Standard conversion sequence S1 is a better conversion
8618 sequence than standard conversion sequence S2 if
8620 --S1 is a proper subsequence of S2 (comparing the conversion
8621 sequences in the canonical form defined by _over.ics.scs_,
8622 excluding any Lvalue Transformation; the identity
8623 conversion sequence is considered to be a subsequence of
8624 any non-identity conversion sequence */
8627 while (t1
->kind
!= ck_identity
)
8628 t1
= next_conversion (t1
);
8629 from_type1
= t1
->type
;
8632 while (t2
->kind
!= ck_identity
)
8633 t2
= next_conversion (t2
);
8634 from_type2
= t2
->type
;
8637 /* One sequence can only be a subsequence of the other if they start with
8638 the same type. They can start with different types when comparing the
8639 second standard conversion sequence in two user-defined conversion
8641 if (same_type_p (from_type1
, from_type2
))
8643 if (is_subseq (ics1
, ics2
))
8645 if (is_subseq (ics2
, ics1
))
8653 --the rank of S1 is better than the rank of S2 (by the rules
8656 Standard conversion sequences are ordered by their ranks: an Exact
8657 Match is a better conversion than a Promotion, which is a better
8658 conversion than a Conversion.
8660 Two conversion sequences with the same rank are indistinguishable
8661 unless one of the following rules applies:
8663 --A conversion that does not a convert a pointer, pointer to member,
8664 or std::nullptr_t to bool is better than one that does.
8666 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
8667 so that we do not have to check it explicitly. */
8668 if (ics1
->rank
< ics2
->rank
)
8670 else if (ics2
->rank
< ics1
->rank
)
8673 to_type1
= ics1
->type
;
8674 to_type2
= ics2
->type
;
8676 /* A conversion from scalar arithmetic type to complex is worse than a
8677 conversion between scalar arithmetic types. */
8678 if (same_type_p (from_type1
, from_type2
)
8679 && ARITHMETIC_TYPE_P (from_type1
)
8680 && ARITHMETIC_TYPE_P (to_type1
)
8681 && ARITHMETIC_TYPE_P (to_type2
)
8682 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
8683 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
8685 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
8691 if (TYPE_PTR_P (from_type1
)
8692 && TYPE_PTR_P (from_type2
)
8693 && TYPE_PTR_P (to_type1
)
8694 && TYPE_PTR_P (to_type2
))
8696 deref_from_type1
= TREE_TYPE (from_type1
);
8697 deref_from_type2
= TREE_TYPE (from_type2
);
8698 deref_to_type1
= TREE_TYPE (to_type1
);
8699 deref_to_type2
= TREE_TYPE (to_type2
);
8701 /* The rules for pointers to members A::* are just like the rules
8702 for pointers A*, except opposite: if B is derived from A then
8703 A::* converts to B::*, not vice versa. For that reason, we
8704 switch the from_ and to_ variables here. */
8705 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
8706 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
8707 || (TYPE_PTRMEMFUNC_P (from_type1
)
8708 && TYPE_PTRMEMFUNC_P (from_type2
)
8709 && TYPE_PTRMEMFUNC_P (to_type1
)
8710 && TYPE_PTRMEMFUNC_P (to_type2
)))
8712 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
8713 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
8714 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
8715 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
8718 if (deref_from_type1
!= NULL_TREE
8719 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
8720 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
8722 /* This was one of the pointer or pointer-like conversions.
8726 --If class B is derived directly or indirectly from class A,
8727 conversion of B* to A* is better than conversion of B* to
8728 void*, and conversion of A* to void* is better than
8729 conversion of B* to void*. */
8730 if (VOID_TYPE_P (deref_to_type1
)
8731 && VOID_TYPE_P (deref_to_type2
))
8733 if (is_properly_derived_from (deref_from_type1
,
8736 else if (is_properly_derived_from (deref_from_type2
,
8740 else if (VOID_TYPE_P (deref_to_type1
)
8741 || VOID_TYPE_P (deref_to_type2
))
8743 if (same_type_p (deref_from_type1
, deref_from_type2
))
8745 if (VOID_TYPE_P (deref_to_type2
))
8747 if (is_properly_derived_from (deref_from_type1
,
8751 /* We know that DEREF_TO_TYPE1 is `void' here. */
8752 else if (is_properly_derived_from (deref_from_type1
,
8757 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
8758 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
8762 --If class B is derived directly or indirectly from class A
8763 and class C is derived directly or indirectly from B,
8765 --conversion of C* to B* is better than conversion of C* to
8768 --conversion of B* to A* is better than conversion of C* to
8770 if (same_type_p (deref_from_type1
, deref_from_type2
))
8772 if (is_properly_derived_from (deref_to_type1
,
8775 else if (is_properly_derived_from (deref_to_type2
,
8779 else if (same_type_p (deref_to_type1
, deref_to_type2
))
8781 if (is_properly_derived_from (deref_from_type2
,
8784 else if (is_properly_derived_from (deref_from_type1
,
8790 else if (CLASS_TYPE_P (non_reference (from_type1
))
8791 && same_type_p (from_type1
, from_type2
))
8793 tree from
= non_reference (from_type1
);
8797 --binding of an expression of type C to a reference of type
8798 B& is better than binding an expression of type C to a
8799 reference of type A&
8801 --conversion of C to B is better than conversion of C to A, */
8802 if (is_properly_derived_from (from
, to_type1
)
8803 && is_properly_derived_from (from
, to_type2
))
8805 if (is_properly_derived_from (to_type1
, to_type2
))
8807 else if (is_properly_derived_from (to_type2
, to_type1
))
8811 else if (CLASS_TYPE_P (non_reference (to_type1
))
8812 && same_type_p (to_type1
, to_type2
))
8814 tree to
= non_reference (to_type1
);
8818 --binding of an expression of type B to a reference of type
8819 A& is better than binding an expression of type C to a
8820 reference of type A&,
8822 --conversion of B to A is better than conversion of C to A */
8823 if (is_properly_derived_from (from_type1
, to
)
8824 && is_properly_derived_from (from_type2
, to
))
8826 if (is_properly_derived_from (from_type2
, from_type1
))
8828 else if (is_properly_derived_from (from_type1
, from_type2
))
8835 --S1 and S2 differ only in their qualification conversion and yield
8836 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
8837 qualification signature of type T1 is a proper subset of the cv-
8838 qualification signature of type T2 */
8839 if (ics1
->kind
== ck_qual
8840 && ics2
->kind
== ck_qual
8841 && same_type_p (from_type1
, from_type2
))
8843 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
8850 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
8851 to an implicit object parameter of a non-static member function
8852 declared without a ref-qualifier, and either S1 binds an lvalue
8853 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
8854 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
8855 draft standard, 13.3.3.2)
8857 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
8858 types to which the references refer are the same type except for
8859 top-level cv-qualifiers, and the type to which the reference
8860 initialized by S2 refers is more cv-qualified than the type to
8861 which the reference initialized by S1 refers.
8863 DR 1328 [over.match.best]: the context is an initialization by
8864 conversion function for direct reference binding (13.3.1.6) of a
8865 reference to function type, the return type of F1 is the same kind of
8866 reference (i.e. lvalue or rvalue) as the reference being initialized,
8867 and the return type of F2 is not. */
8869 if (ref_conv1
&& ref_conv2
)
8871 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
8872 && (ref_conv1
->rvaluedness_matches_p
8873 != ref_conv2
->rvaluedness_matches_p
)
8874 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
8875 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
8876 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
8878 if (ref_conv1
->bad_p
8879 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
8880 TREE_TYPE (ref_conv2
->type
)))
8881 /* Don't prefer a bad conversion that drops cv-quals to a bad
8882 conversion with the wrong rvalueness. */
8884 return (ref_conv1
->rvaluedness_matches_p
8885 - ref_conv2
->rvaluedness_matches_p
);
8888 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
8890 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
8891 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
8892 if (ref_conv1
->bad_p
)
8894 /* Prefer the one that drops fewer cv-quals. */
8895 tree ftype
= next_conversion (ref_conv1
)->type
;
8896 int fquals
= cp_type_quals (ftype
);
8900 return comp_cv_qualification (q2
, q1
);
8904 /* Neither conversion sequence is better than the other. */
8908 /* The source type for this standard conversion sequence. */
8911 source_type (conversion
*t
)
8913 for (;; t
= next_conversion (t
))
8915 if (t
->kind
== ck_user
8916 || t
->kind
== ck_ambig
8917 || t
->kind
== ck_identity
)
8923 /* Note a warning about preferring WINNER to LOSER. We do this by storing
8924 a pointer to LOSER and re-running joust to produce the warning if WINNER
8925 is actually used. */
8928 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
8930 candidate_warning
*cw
= (candidate_warning
*)
8931 conversion_obstack_alloc (sizeof (candidate_warning
));
8933 cw
->next
= winner
->warnings
;
8934 winner
->warnings
= cw
;
8937 /* Compare two candidates for overloading as described in
8938 [over.match.best]. Return values:
8940 1: cand1 is better than cand2
8941 -1: cand2 is better than cand1
8942 0: cand1 and cand2 are indistinguishable */
8945 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
8946 tsubst_flags_t complain
)
8949 int off1
= 0, off2
= 0;
8953 /* Candidates that involve bad conversions are always worse than those
8955 if (cand1
->viable
> cand2
->viable
)
8957 if (cand1
->viable
< cand2
->viable
)
8960 /* If we have two pseudo-candidates for conversions to the same type,
8961 or two candidates for the same function, arbitrarily pick one. */
8962 if (cand1
->fn
== cand2
->fn
8963 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
8966 /* Prefer a non-deleted function over an implicitly deleted move
8967 constructor or assignment operator. This differs slightly from the
8968 wording for issue 1402 (which says the move op is ignored by overload
8969 resolution), but this way produces better error messages. */
8970 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
8971 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
8972 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
8974 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
8975 && move_fn_p (cand1
->fn
))
8977 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
8978 && move_fn_p (cand2
->fn
))
8982 /* a viable function F1
8983 is defined to be a better function than another viable function F2 if
8984 for all arguments i, ICSi(F1) is not a worse conversion sequence than
8985 ICSi(F2), and then */
8987 /* for some argument j, ICSj(F1) is a better conversion sequence than
8990 /* For comparing static and non-static member functions, we ignore
8991 the implicit object parameter of the non-static function. The
8992 standard says to pretend that the static function has an object
8993 parm, but that won't work with operator overloading. */
8994 len
= cand1
->num_convs
;
8995 if (len
!= cand2
->num_convs
)
8997 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
8998 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
9000 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
9001 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
9002 /* We're comparing a near-match list constructor and a near-match
9003 non-list constructor. Just treat them as unordered. */
9006 gcc_assert (static_1
!= static_2
);
9017 for (i
= 0; i
< len
; ++i
)
9019 conversion
*t1
= cand1
->convs
[i
+ off1
];
9020 conversion
*t2
= cand2
->convs
[i
+ off2
];
9021 int comp
= compare_ics (t1
, t2
);
9025 if ((complain
& tf_warning
)
9027 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
9028 == cr_std
+ cr_promotion
)
9029 && t1
->kind
== ck_std
9030 && t2
->kind
== ck_std
9031 && TREE_CODE (t1
->type
) == INTEGER_TYPE
9032 && TREE_CODE (t2
->type
) == INTEGER_TYPE
9033 && (TYPE_PRECISION (t1
->type
)
9034 == TYPE_PRECISION (t2
->type
))
9035 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
9036 || (TREE_CODE (next_conversion (t1
)->type
)
9039 tree type
= next_conversion (t1
)->type
;
9041 struct z_candidate
*w
, *l
;
9043 type1
= t1
->type
, type2
= t2
->type
,
9044 w
= cand1
, l
= cand2
;
9046 type1
= t2
->type
, type2
= t1
->type
,
9047 w
= cand2
, l
= cand1
;
9051 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
9052 type
, type1
, type2
);
9053 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
9059 if (winner
&& comp
!= winner
)
9068 /* warn about confusing overload resolution for user-defined conversions,
9069 either between a constructor and a conversion op, or between two
9071 if ((complain
& tf_warning
)
9072 && winner
&& warn_conversion
&& cand1
->second_conv
9073 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
9074 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
9076 struct z_candidate
*w
, *l
;
9077 bool give_warning
= false;
9080 w
= cand1
, l
= cand2
;
9082 w
= cand2
, l
= cand1
;
9084 /* We don't want to complain about `X::operator T1 ()'
9085 beating `X::operator T2 () const', when T2 is a no less
9086 cv-qualified version of T1. */
9087 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
9088 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
9090 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
9091 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
9093 if (TREE_CODE (t
) == TREE_CODE (f
) && POINTER_TYPE_P (t
))
9098 if (!comp_ptr_ttypes (t
, f
))
9099 give_warning
= true;
9102 give_warning
= true;
9108 tree source
= source_type (w
->convs
[0]);
9109 if (! DECL_CONSTRUCTOR_P (w
->fn
))
9110 source
= TREE_TYPE (source
);
9111 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
9112 && warning (OPT_Wconversion
, " for conversion from %qT to %qT",
9113 source
, w
->second_conv
->type
))
9115 inform (input_location
, " because conversion sequence for the argument is better");
9125 /* DR 495 moved this tiebreaker above the template ones. */
9127 the context is an initialization by user-defined conversion (see
9128 _dcl.init_ and _over.match.user_) and the standard conversion
9129 sequence from the return type of F1 to the destination type (i.e.,
9130 the type of the entity being initialized) is a better conversion
9131 sequence than the standard conversion sequence from the return type
9132 of F2 to the destination type. */
9134 if (cand1
->second_conv
)
9136 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
9142 F1 is a non-template function and F2 is a template function
9145 if (!cand1
->template_decl
&& cand2
->template_decl
)
9147 else if (cand1
->template_decl
&& !cand2
->template_decl
)
9151 F1 and F2 are template functions and the function template for F1 is
9152 more specialized than the template for F2 according to the partial
9155 if (cand1
->template_decl
&& cand2
->template_decl
)
9157 winner
= more_specialized_fn
9158 (TI_TEMPLATE (cand1
->template_decl
),
9159 TI_TEMPLATE (cand2
->template_decl
),
9160 /* [temp.func.order]: The presence of unused ellipsis and default
9161 arguments has no effect on the partial ordering of function
9162 templates. add_function_candidate() will not have
9163 counted the "this" argument for constructors. */
9164 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
9170 // or, if not that, F1 is more constrained than F2.
9171 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
9173 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
9178 /* Check whether we can discard a builtin candidate, either because we
9179 have two identical ones or matching builtin and non-builtin candidates.
9181 (Pedantically in the latter case the builtin which matched the user
9182 function should not be added to the overload set, but we spot it here.
9185 ... the builtin candidates include ...
9186 - do not have the same parameter type list as any non-template
9187 non-member candidate. */
9189 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
9191 for (i
= 0; i
< len
; ++i
)
9192 if (!same_type_p (cand1
->convs
[i
]->type
,
9193 cand2
->convs
[i
]->type
))
9195 if (i
== cand1
->num_convs
)
9197 if (cand1
->fn
== cand2
->fn
)
9198 /* Two built-in candidates; arbitrarily pick one. */
9200 else if (identifier_p (cand1
->fn
))
9201 /* cand1 is built-in; prefer cand2. */
9204 /* cand2 is built-in; prefer cand1. */
9209 /* For candidates of a multi-versioned function, make the version with
9210 the highest priority win. This version will be checked for dispatching
9211 first. If this version can be inlined into the caller, the front-end
9212 will simply make a direct call to this function. */
9214 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
9215 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
9216 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
9217 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
9219 tree f1
= TREE_TYPE (cand1
->fn
);
9220 tree f2
= TREE_TYPE (cand2
->fn
);
9221 tree p1
= TYPE_ARG_TYPES (f1
);
9222 tree p2
= TYPE_ARG_TYPES (f2
);
9224 /* Check if cand1->fn and cand2->fn are versions of the same function. It
9225 is possible that cand1->fn and cand2->fn are function versions but of
9226 different functions. Check types to see if they are versions of the same
9228 if (compparms (p1
, p2
)
9229 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
9231 /* Always make the version with the higher priority, more
9232 specialized, win. */
9233 gcc_assert (targetm
.compare_version_priority
);
9234 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
9241 /* If the two function declarations represent the same function (this can
9242 happen with declarations in multiple scopes and arg-dependent lookup),
9243 arbitrarily choose one. But first make sure the default args we're
9245 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
9246 && equal_functions (cand1
->fn
, cand2
->fn
))
9248 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
9249 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
9251 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
9253 for (i
= 0; i
< len
; ++i
)
9255 /* Don't crash if the fn is variadic. */
9258 parms1
= TREE_CHAIN (parms1
);
9259 parms2
= TREE_CHAIN (parms2
);
9263 parms1
= TREE_CHAIN (parms1
);
9265 parms2
= TREE_CHAIN (parms2
);
9269 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
9270 TREE_PURPOSE (parms2
)))
9274 if (complain
& tf_error
)
9276 if (permerror (input_location
,
9277 "default argument mismatch in "
9278 "overload resolution"))
9280 inform (input_location
,
9281 " candidate 1: %q+#F", cand1
->fn
);
9282 inform (input_location
,
9283 " candidate 2: %q+#F", cand2
->fn
);
9290 add_warning (cand1
, cand2
);
9293 parms1
= TREE_CHAIN (parms1
);
9294 parms2
= TREE_CHAIN (parms2
);
9302 /* Extension: If the worst conversion for one candidate is worse than the
9303 worst conversion for the other, take the first. */
9304 if (!pedantic
&& (complain
& tf_warning_or_error
))
9306 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
9307 struct z_candidate
*w
= 0, *l
= 0;
9309 for (i
= 0; i
< len
; ++i
)
9311 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
9312 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
9313 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
9314 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
9317 winner
= 1, w
= cand1
, l
= cand2
;
9319 winner
= -1, w
= cand2
, l
= cand1
;
9322 /* Don't choose a deleted function over ambiguity. */
9323 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
9327 pedwarn (input_location
, 0,
9328 "ISO C++ says that these are ambiguous, even "
9329 "though the worst conversion for the first is better than "
9330 "the worst conversion for the second:");
9331 print_z_candidate (input_location
, _("candidate 1:"), w
);
9332 print_z_candidate (input_location
, _("candidate 2:"), l
);
9340 gcc_assert (!winner
);
9344 /* Given a list of candidates for overloading, find the best one, if any.
9345 This algorithm has a worst case of O(2n) (winner is last), and a best
9346 case of O(n/2) (totally ambiguous); much better than a sorting
9349 static struct z_candidate
*
9350 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
9352 struct z_candidate
*champ
= candidates
, *challenger
;
9354 int champ_compared_to_predecessor
= 0;
9356 /* Walk through the list once, comparing each current champ to the next
9357 candidate, knocking out a candidate or two with each comparison. */
9359 for (challenger
= champ
->next
; challenger
; )
9361 fate
= joust (champ
, challenger
, 0, complain
);
9363 challenger
= challenger
->next
;
9368 champ
= challenger
->next
;
9371 champ_compared_to_predecessor
= 0;
9376 champ_compared_to_predecessor
= 1;
9379 challenger
= champ
->next
;
9383 /* Make sure the champ is better than all the candidates it hasn't yet
9384 been compared to. */
9386 for (challenger
= candidates
;
9388 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
9389 challenger
= challenger
->next
)
9391 fate
= joust (champ
, challenger
, 0, complain
);
9399 /* Returns nonzero if things of type FROM can be converted to TO. */
9402 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
9404 tree arg
= NULL_TREE
;
9405 /* implicit_conversion only considers user-defined conversions
9406 if it has an expression for the call argument list. */
9407 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
9408 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
9409 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
9412 /* Returns nonzero if things of type FROM can be converted to TO with a
9413 standard conversion. */
9416 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
9418 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
9421 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
9424 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
9425 tsubst_flags_t complain
)
9431 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9432 p
= conversion_obstack_alloc (0);
9433 /* We want to discard any access checks done for this test,
9434 as we might not be in the appropriate access context and
9435 we'll do the check again when we actually perform the
9437 push_deferring_access_checks (dk_deferred
);
9439 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
9441 ok_p
= (t
&& !t
->bad_p
);
9443 /* Discard the access checks now. */
9444 pop_deferring_access_checks ();
9445 /* Free all the conversions we allocated. */
9446 obstack_free (&conversion_obstack
, p
);
9451 /* Like can_convert_arg, but allows dubious conversions as well. */
9454 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
9455 tsubst_flags_t complain
)
9460 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9461 p
= conversion_obstack_alloc (0);
9462 /* Try to perform the conversion. */
9463 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
9465 /* Free all the conversions we allocated. */
9466 obstack_free (&conversion_obstack
, p
);
9471 /* Convert EXPR to TYPE. Return the converted expression.
9473 Note that we allow bad conversions here because by the time we get to
9474 this point we are committed to doing the conversion. If we end up
9475 doing a bad conversion, convert_like will complain. */
9478 perform_implicit_conversion_flags (tree type
, tree expr
,
9479 tsubst_flags_t complain
, int flags
)
9483 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
9485 if (error_operand_p (expr
))
9486 return error_mark_node
;
9488 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9489 p
= conversion_obstack_alloc (0);
9491 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
9497 if (complain
& tf_error
)
9499 /* If expr has unknown type, then it is an overloaded function.
9500 Call instantiate_type to get good error messages. */
9501 if (TREE_TYPE (expr
) == unknown_type_node
)
9502 instantiate_type (type
, expr
, complain
);
9503 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
9504 /* We gave an error. */;
9506 error_at (loc
, "could not convert %qE from %qT to %qT", expr
,
9507 TREE_TYPE (expr
), type
);
9509 expr
= error_mark_node
;
9511 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
9513 /* In a template, we are only concerned about determining the
9514 type of non-dependent expressions, so we do not have to
9515 perform the actual conversion. But for initializers, we
9516 need to be able to perform it at instantiation
9517 (or instantiate_non_dependent_expr) time. */
9518 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
9519 if (!(flags
& LOOKUP_ONLYCONVERTING
))
9520 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
9523 expr
= convert_like (conv
, expr
, complain
);
9525 /* Free all the conversions we allocated. */
9526 obstack_free (&conversion_obstack
, p
);
9532 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
9534 return perform_implicit_conversion_flags (type
, expr
, complain
,
9538 /* Convert EXPR to TYPE (as a direct-initialization) if that is
9539 permitted. If the conversion is valid, the converted expression is
9540 returned. Otherwise, NULL_TREE is returned, except in the case
9541 that TYPE is a class type; in that case, an error is issued. If
9542 C_CAST_P is true, then this direct-initialization is taking
9543 place as part of a static_cast being attempted as part of a C-style
9547 perform_direct_initialization_if_possible (tree type
,
9550 tsubst_flags_t complain
)
9555 if (type
== error_mark_node
|| error_operand_p (expr
))
9556 return error_mark_node
;
9559 If the destination type is a (possibly cv-qualified) class type:
9561 -- If the initialization is direct-initialization ...,
9562 constructors are considered. ... If no constructor applies, or
9563 the overload resolution is ambiguous, the initialization is
9565 if (CLASS_TYPE_P (type
))
9567 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
9568 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
9569 &args
, type
, LOOKUP_NORMAL
, complain
);
9570 release_tree_vector (args
);
9571 return build_cplus_new (type
, expr
, complain
);
9574 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9575 p
= conversion_obstack_alloc (0);
9577 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
9579 LOOKUP_NORMAL
, complain
);
9580 if (!conv
|| conv
->bad_p
)
9583 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0, 0,
9584 /*issue_conversion_warnings=*/false,
9588 /* Free all the conversions we allocated. */
9589 obstack_free (&conversion_obstack
, p
);
9594 /* When initializing a reference that lasts longer than a full-expression,
9595 this special rule applies:
9599 The temporary to which the reference is bound or the temporary
9600 that is the complete object to which the reference is bound
9601 persists for the lifetime of the reference.
9603 The temporaries created during the evaluation of the expression
9604 initializing the reference, except the temporary to which the
9605 reference is bound, are destroyed at the end of the
9606 full-expression in which they are created.
9608 In that case, we store the converted expression into a new
9609 VAR_DECL in a new scope.
9611 However, we want to be careful not to create temporaries when
9612 they are not required. For example, given:
9615 struct D : public B {};
9619 there is no need to copy the return value from "f"; we can just
9620 extend its lifetime. Similarly, given:
9623 struct T { operator S(); };
9627 we can extend the lifetime of the return value of the conversion
9630 The next several functions are involved in this lifetime extension. */
9632 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
9633 reference is being bound to a temporary. Create and return a new
9634 VAR_DECL with the indicated TYPE; this variable will store the value to
9635 which the reference is bound. */
9638 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
9642 /* Create the variable. */
9643 var
= create_temporary_var (type
);
9645 /* Register the variable. */
9647 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
9649 /* Namespace-scope or local static; give it a mangled name. */
9650 /* FIXME share comdat with decl? */
9653 TREE_STATIC (var
) = TREE_STATIC (decl
);
9654 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
9655 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
9656 name
= mangle_ref_init_variable (decl
);
9657 DECL_NAME (var
) = name
;
9658 SET_DECL_ASSEMBLER_NAME (var
, name
);
9659 var
= pushdecl_top_level (var
);
9662 /* Create a new cleanup level if necessary. */
9663 maybe_push_cleanup_level (type
);
9668 /* EXPR is the initializer for a variable DECL of reference or
9669 std::initializer_list type. Create, push and return a new VAR_DECL
9670 for the initializer so that it will live as long as DECL. Any
9671 cleanup for the new variable is returned through CLEANUP, and the
9672 code to initialize the new variable is returned through INITP. */
9675 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
9682 /* Create the temporary variable. */
9683 type
= TREE_TYPE (expr
);
9684 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
9685 layout_decl (var
, 0);
9686 /* If the rvalue is the result of a function call it will be
9687 a TARGET_EXPR. If it is some other construct (such as a
9688 member access expression where the underlying object is
9689 itself the result of a function call), turn it into a
9690 TARGET_EXPR here. It is important that EXPR be a
9691 TARGET_EXPR below since otherwise the INIT_EXPR will
9692 attempt to make a bitwise copy of EXPR to initialize
9694 if (TREE_CODE (expr
) != TARGET_EXPR
)
9695 expr
= get_target_expr (expr
);
9697 if (TREE_CODE (decl
) == FIELD_DECL
9698 && extra_warnings
&& !TREE_NO_WARNING (decl
))
9700 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
9701 "until the constructor exits", decl
);
9702 TREE_NO_WARNING (decl
) = true;
9705 /* Recursively extend temps in this initializer. */
9706 TARGET_EXPR_INITIAL (expr
)
9707 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
9709 /* Any reference temp has a non-trivial initializer. */
9710 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
9712 /* If the initializer is constant, put it in DECL_INITIAL so we get
9713 static initialization and use in constant expressions. */
9714 init
= maybe_constant_init (expr
);
9715 if (TREE_CONSTANT (init
))
9717 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
9719 /* 5.19 says that a constant expression can include an
9720 lvalue-rvalue conversion applied to "a glvalue of literal type
9721 that refers to a non-volatile temporary object initialized
9722 with a constant expression". Rather than try to communicate
9723 that this VAR_DECL is a temporary, just mark it constexpr.
9725 Currently this is only useful for initializer_list temporaries,
9726 since reference vars can't appear in constant expressions. */
9727 DECL_DECLARED_CONSTEXPR_P (var
) = true;
9728 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
9729 TREE_CONSTANT (var
) = true;
9731 DECL_INITIAL (var
) = init
;
9735 /* Create the INIT_EXPR that will initialize the temporary
9737 init
= split_nonconstant_init (var
, expr
);
9738 if (at_function_scope_p ())
9740 add_decl_expr (var
);
9742 if (TREE_STATIC (var
))
9743 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
9746 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
9748 vec_safe_push (*cleanups
, cleanup
);
9751 /* We must be careful to destroy the temporary only
9752 after its initialization has taken place. If the
9753 initialization throws an exception, then the
9754 destructor should not be run. We cannot simply
9755 transform INIT into something like:
9757 (INIT, ({ CLEANUP_STMT; }))
9759 because emit_local_var always treats the
9760 initializer as a full-expression. Thus, the
9761 destructor would run too early; it would run at the
9762 end of initializing the reference variable, rather
9763 than at the end of the block enclosing the
9766 The solution is to pass back a cleanup expression
9767 which the caller is responsible for attaching to
9768 the statement tree. */
9772 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
9773 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
9775 if (CP_DECL_THREAD_LOCAL_P (var
))
9776 tls_aggregates
= tree_cons (NULL_TREE
, var
,
9779 static_aggregates
= tree_cons (NULL_TREE
, var
,
9783 /* Check whether the dtor is callable. */
9784 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
9786 /* Avoid -Wunused-variable warning (c++/38958). */
9787 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
9789 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
9795 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
9796 initializing a variable of that TYPE. */
9799 initialize_reference (tree type
, tree expr
,
9800 int flags
, tsubst_flags_t complain
)
9804 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
9806 if (type
== error_mark_node
|| error_operand_p (expr
))
9807 return error_mark_node
;
9809 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9810 p
= conversion_obstack_alloc (0);
9812 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
9814 if (!conv
|| conv
->bad_p
)
9816 if (complain
& tf_error
)
9819 convert_like (conv
, expr
, complain
);
9820 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
9821 && !TYPE_REF_IS_RVALUE (type
)
9822 && !real_lvalue_p (expr
))
9823 error_at (loc
, "invalid initialization of non-const reference of "
9824 "type %qT from an rvalue of type %qT",
9825 type
, TREE_TYPE (expr
));
9827 error_at (loc
, "invalid initialization of reference of type "
9828 "%qT from expression of type %qT", type
,
9831 return error_mark_node
;
9834 if (conv
->kind
== ck_ref_bind
)
9835 /* Perform the conversion. */
9836 expr
= convert_like (conv
, expr
, complain
);
9837 else if (conv
->kind
== ck_ambig
)
9838 /* We gave an error in build_user_type_conversion_1. */
9839 expr
= error_mark_node
;
9843 /* Free all the conversions we allocated. */
9844 obstack_free (&conversion_obstack
, p
);
9849 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
9850 which is bound either to a reference or a std::initializer_list. */
9853 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
9858 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
9860 TREE_OPERAND (sub
, 1)
9861 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
9864 if (TREE_CODE (sub
) != ADDR_EXPR
)
9866 /* Deal with binding to a subobject. */
9867 for (p
= &TREE_OPERAND (sub
, 0); TREE_CODE (*p
) == COMPONENT_REF
; )
9868 p
= &TREE_OPERAND (*p
, 0);
9869 if (TREE_CODE (*p
) == TARGET_EXPR
)
9871 tree subinit
= NULL_TREE
;
9872 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
9873 recompute_tree_invariant_for_addr_expr (sub
);
9875 init
= fold_convert (TREE_TYPE (init
), sub
);
9877 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
9882 /* INIT is part of the initializer for DECL. If there are any
9883 reference or initializer lists being initialized, extend their
9884 lifetime to match that of DECL. */
9887 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
9889 tree type
= TREE_TYPE (init
);
9890 if (processing_template_decl
)
9892 if (TREE_CODE (type
) == REFERENCE_TYPE
)
9893 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
9894 else if (is_std_init_list (type
))
9896 /* The temporary array underlying a std::initializer_list
9897 is handled like a reference temporary. */
9899 if (TREE_CODE (ctor
) == TARGET_EXPR
)
9900 ctor
= TARGET_EXPR_INITIAL (ctor
);
9901 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
9903 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
9904 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
9905 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
9908 else if (TREE_CODE (init
) == CONSTRUCTOR
)
9912 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (init
);
9913 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
9914 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
9920 /* Returns true iff an initializer for TYPE could contain temporaries that
9921 need to be extended because they are bound to references or
9922 std::initializer_list. */
9925 type_has_extended_temps (tree type
)
9927 type
= strip_array_types (type
);
9928 if (TREE_CODE (type
) == REFERENCE_TYPE
)
9930 if (CLASS_TYPE_P (type
))
9932 if (is_std_init_list (type
))
9934 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
9935 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
9936 if (type_has_extended_temps (TREE_TYPE (f
)))
9942 /* Returns true iff TYPE is some variant of std::initializer_list. */
9945 is_std_init_list (tree type
)
9947 /* Look through typedefs. */
9950 if (cxx_dialect
== cxx98
)
9952 type
= TYPE_MAIN_VARIANT (type
);
9953 return (CLASS_TYPE_P (type
)
9954 && CP_TYPE_CONTEXT (type
) == std_node
9955 && strcmp (TYPE_NAME_STRING (type
), "initializer_list") == 0);
9958 /* Returns true iff DECL is a list constructor: i.e. a constructor which
9959 will accept an argument list of a single std::initializer_list<T>. */
9962 is_list_ctor (tree decl
)
9964 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
9967 if (!args
|| args
== void_list_node
)
9970 arg
= non_reference (TREE_VALUE (args
));
9971 if (!is_std_init_list (arg
))
9974 args
= TREE_CHAIN (args
);
9976 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
9977 /* There are more non-defaulted parms. */
9983 #include "gt-cp-call.h"