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
{
68 /* The rank of the conversion. Order of the enumerals matters; better
69 conversions should come earlier in the list. */
71 enum conversion_rank
{
82 /* An implicit conversion sequence, in the sense of [over.best.ics].
83 The first conversion to be performed is at the end of the chain.
84 That conversion is always a cr_identity conversion. */
87 /* The kind of conversion represented by this step. */
89 /* The rank of this conversion. */
91 BOOL_BITFIELD user_conv_p
: 1;
92 BOOL_BITFIELD ellipsis_p
: 1;
93 BOOL_BITFIELD this_p
: 1;
94 /* True if this conversion would be permitted with a bending of
95 language standards, e.g. disregarding pointer qualifiers or
96 converting integers to pointers. */
97 BOOL_BITFIELD bad_p
: 1;
98 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
99 temporary should be created to hold the result of the
101 BOOL_BITFIELD need_temporary_p
: 1;
102 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
103 from a pointer-to-derived to pointer-to-base is being performed. */
104 BOOL_BITFIELD base_p
: 1;
105 /* If KIND is ck_ref_bind, true when either an lvalue reference is
106 being bound to an lvalue expression or an rvalue reference is
107 being bound to an rvalue expression. If KIND is ck_rvalue,
108 true when we should treat an lvalue as an rvalue (12.8p33). If
109 KIND is ck_base, always false. */
110 BOOL_BITFIELD rvaluedness_matches_p
: 1;
111 BOOL_BITFIELD check_narrowing
: 1;
112 /* The type of the expression resulting from the conversion. */
115 /* The next conversion in the chain. Since the conversions are
116 arranged from outermost to innermost, the NEXT conversion will
117 actually be performed before this conversion. This variant is
118 used only when KIND is neither ck_identity, ck_ambig nor
119 ck_list. Please use the next_conversion function instead
120 of using this field directly. */
122 /* The expression at the beginning of the conversion chain. This
123 variant is used only if KIND is ck_identity or ck_ambig. */
125 /* The array of conversions for an initializer_list, so this
126 variant is used only when KIN D is ck_list. */
129 /* The function candidate corresponding to this conversion
130 sequence. This field is only used if KIND is ck_user. */
131 struct z_candidate
*cand
;
134 #define CONVERSION_RANK(NODE) \
135 ((NODE)->bad_p ? cr_bad \
136 : (NODE)->ellipsis_p ? cr_ellipsis \
137 : (NODE)->user_conv_p ? cr_user \
140 #define BAD_CONVERSION_RANK(NODE) \
141 ((NODE)->ellipsis_p ? cr_ellipsis \
142 : (NODE)->user_conv_p ? cr_user \
145 static struct obstack conversion_obstack
;
146 static bool conversion_obstack_initialized
;
147 struct rejection_reason
;
149 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
150 static int equal_functions (tree
, tree
);
151 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
153 static int compare_ics (conversion
*, conversion
*);
154 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
155 static tree
build_java_interface_fn_ref (tree
, tree
);
156 #define convert_like(CONV, EXPR, COMPLAIN) \
157 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
158 /*issue_conversion_warnings=*/true, \
159 /*c_cast_p=*/false, (COMPLAIN))
160 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
161 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
162 /*issue_conversion_warnings=*/true, \
163 /*c_cast_p=*/false, (COMPLAIN))
164 static tree
convert_like_real (conversion
*, tree
, tree
, int, int, bool,
165 bool, tsubst_flags_t
);
166 static void op_error (location_t
, enum tree_code
, enum tree_code
, tree
,
168 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
170 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
171 static void print_z_candidates (location_t
, struct z_candidate
*);
172 static tree
build_this (tree
);
173 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
174 static bool any_strictly_viable (struct z_candidate
*);
175 static struct z_candidate
*add_template_candidate
176 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
177 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
178 static struct z_candidate
*add_template_candidate_real
179 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
180 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
181 static struct z_candidate
*add_template_conv_candidate
182 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
183 tree
, tree
, tree
, tsubst_flags_t
);
184 static void add_builtin_candidates
185 (struct z_candidate
**, enum tree_code
, enum tree_code
,
186 tree
, tree
*, int, tsubst_flags_t
);
187 static void add_builtin_candidate
188 (struct z_candidate
**, enum tree_code
, enum tree_code
,
189 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
190 static bool is_complete (tree
);
191 static void build_builtin_candidate
192 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
193 int, tsubst_flags_t
);
194 static struct z_candidate
*add_conv_candidate
195 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
196 tree
, tsubst_flags_t
);
197 static struct z_candidate
*add_function_candidate
198 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
199 tree
, int, tsubst_flags_t
);
200 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
202 static conversion
*standard_conversion (tree
, tree
, tree
, bool, int);
203 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
205 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
206 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
207 static conversion
*next_conversion (conversion
*);
208 static bool is_subseq (conversion
*, conversion
*);
209 static conversion
*maybe_handle_ref_bind (conversion
**);
210 static void maybe_handle_implicit_object (conversion
**);
211 static struct z_candidate
*add_candidate
212 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
213 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
214 static tree
source_type (conversion
*);
215 static void add_warning (struct z_candidate
*, struct z_candidate
*);
216 static bool reference_compatible_p (tree
, tree
);
217 static conversion
*direct_reference_binding (tree
, conversion
*);
218 static bool promoted_arithmetic_type_p (tree
);
219 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
220 static char *name_as_c_string (tree
, tree
, bool *);
221 static tree
prep_operand (tree
);
222 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
223 bool, tree
, tree
, int, struct z_candidate
**,
225 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
226 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
228 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
229 NAME can take many forms... */
232 check_dtor_name (tree basetype
, tree name
)
234 /* Just accept something we've already complained about. */
235 if (name
== error_mark_node
)
238 if (TREE_CODE (name
) == TYPE_DECL
)
239 name
= TREE_TYPE (name
);
240 else if (TYPE_P (name
))
242 else if (identifier_p (name
))
244 if ((MAYBE_CLASS_TYPE_P (basetype
)
245 && name
== constructor_name (basetype
))
246 || (TREE_CODE (basetype
) == ENUMERAL_TYPE
247 && name
== TYPE_IDENTIFIER (basetype
)))
250 name
= get_type_value (name
);
256 template <class T> struct S { ~S(); };
260 NAME will be a class template. */
261 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
265 if (!name
|| name
== error_mark_node
)
267 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
270 /* We want the address of a function or method. We avoid creating a
271 pointer-to-member function. */
274 build_addr_func (tree function
, tsubst_flags_t complain
)
276 tree type
= TREE_TYPE (function
);
278 /* We have to do these by hand to avoid real pointer to member
280 if (TREE_CODE (type
) == METHOD_TYPE
)
282 if (TREE_CODE (function
) == OFFSET_REF
)
284 tree object
= build_address (TREE_OPERAND (function
, 0));
285 return get_member_function_from_ptrfunc (&object
,
286 TREE_OPERAND (function
, 1),
289 function
= build_address (function
);
292 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
297 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
298 POINTER_TYPE to those. Note, pointer to member function types
299 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
300 two variants. build_call_a is the primitive taking an array of
301 arguments, while build_call_n is a wrapper that handles varargs. */
304 build_call_n (tree function
, int n
, ...)
307 return build_call_a (function
, 0, NULL
);
310 tree
*argarray
= XALLOCAVEC (tree
, n
);
315 for (i
= 0; i
< n
; i
++)
316 argarray
[i
] = va_arg (ap
, tree
);
318 return build_call_a (function
, n
, argarray
);
322 /* Update various flags in cfun and the call itself based on what is being
323 called. Split out of build_call_a so that bot_manip can use it too. */
326 set_flags_from_callee (tree call
)
329 tree decl
= get_callee_fndecl (call
);
331 /* We check both the decl and the type; a function may be known not to
332 throw without being declared throw(). */
333 nothrow
= decl
&& TREE_NOTHROW (decl
);
334 if (CALL_EXPR_FN (call
))
335 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call
))));
336 else if (internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
339 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
340 cp_function_chain
->can_throw
= 1;
342 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
343 current_function_returns_abnormally
= 1;
345 TREE_NOTHROW (call
) = nothrow
;
349 build_call_a (tree function
, int n
, tree
*argarray
)
356 function
= build_addr_func (function
, tf_warning_or_error
);
358 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
359 fntype
= TREE_TYPE (TREE_TYPE (function
));
360 gcc_assert (TREE_CODE (fntype
) == FUNCTION_TYPE
361 || TREE_CODE (fntype
) == METHOD_TYPE
);
362 result_type
= TREE_TYPE (fntype
);
363 /* An rvalue has no cv-qualifiers. */
364 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
365 result_type
= cv_unqualified (result_type
);
367 function
= build_call_array_loc (input_location
,
368 result_type
, function
, n
, argarray
);
369 set_flags_from_callee (function
);
371 decl
= get_callee_fndecl (function
);
373 if (decl
&& !TREE_USED (decl
))
375 /* We invoke build_call directly for several library
376 functions. These may have been declared normally if
377 we're building libgcc, so we can't just check
379 gcc_assert (DECL_ARTIFICIAL (decl
)
380 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
385 require_complete_eh_spec_types (fntype
, decl
);
387 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
389 /* Don't pass empty class objects by value. This is useful
390 for tags in STL, which are used to control overload resolution.
391 We don't need to handle other cases of copying empty classes. */
392 if (! decl
|| ! DECL_BUILT_IN (decl
))
393 for (i
= 0; i
< n
; i
++)
395 tree arg
= CALL_EXPR_ARG (function
, i
);
396 if (is_empty_class (TREE_TYPE (arg
))
397 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
399 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
400 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
401 CALL_EXPR_ARG (function
, i
) = arg
;
408 /* New overloading code. */
412 struct candidate_warning
{
414 candidate_warning
*next
;
417 /* Information for providing diagnostics about why overloading failed. */
419 enum rejection_reason_code
{
422 rr_explicit_conversion
,
423 rr_template_conversion
,
425 rr_bad_arg_conversion
,
426 rr_template_unification
,
428 rr_constraint_failure
431 struct conversion_info
{
432 /* The index of the argument, 0-based. */
434 /* The actual argument or its type. */
436 /* The type of the parameter. */
440 struct rejection_reason
{
441 enum rejection_reason_code code
;
443 /* Information about an arity mismatch. */
445 /* The expected number of arguments. */
447 /* The actual number of arguments in the call. */
449 /* Whether the call was a varargs call. */
452 /* Information about an argument conversion mismatch. */
453 struct conversion_info conversion
;
454 /* Same, but for bad argument conversions. */
455 struct conversion_info bad_conversion
;
456 /* Information about template unification failures. These are the
457 parameters passed to fn_type_unification. */
465 unification_kind_t strict
;
467 } template_unification
;
468 /* Information about template instantiation failures. These are the
469 parameters passed to instantiate_template. */
473 } template_instantiation
;
478 /* The FUNCTION_DECL that will be called if this candidate is
479 selected by overload resolution. */
481 /* If not NULL_TREE, the first argument to use when calling this
484 /* The rest of the arguments to use when calling this function. If
485 there are no further arguments this may be NULL or it may be an
487 const vec
<tree
, va_gc
> *args
;
488 /* The implicit conversion sequences for each of the arguments to
491 /* The number of implicit conversion sequences. */
493 /* If FN is a user-defined conversion, the standard conversion
494 sequence from the type returned by FN to the desired destination
496 conversion
*second_conv
;
497 struct rejection_reason
*reason
;
498 /* If FN is a member function, the binfo indicating the path used to
499 qualify the name of FN at the call site. This path is used to
500 determine whether or not FN is accessible if it is selected by
501 overload resolution. The DECL_CONTEXT of FN will always be a
502 (possibly improper) base of this binfo. */
504 /* If FN is a non-static member function, the binfo indicating the
505 subobject to which the `this' pointer should be converted if FN
506 is selected by overload resolution. The type pointed to by
507 the `this' pointer must correspond to the most derived class
508 indicated by the CONVERSION_PATH. */
509 tree conversion_path
;
512 candidate_warning
*warnings
;
516 /* The flags active in add_candidate. */
520 /* Returns true iff T is a null pointer constant in the sense of
524 null_ptr_cst_p (tree t
)
526 tree type
= TREE_TYPE (t
);
530 A null pointer constant is an integral constant expression
531 (_expr.const_) rvalue of integer type that evaluates to zero or
532 an rvalue of type std::nullptr_t. */
533 if (NULLPTR_TYPE_P (type
))
536 if (cxx_dialect
>= cxx11
)
538 /* Core issue 903 says only literal 0 is a null pointer constant. */
539 if (TREE_CODE (type
) == INTEGER_TYPE
540 && TREE_CODE (t
) == INTEGER_CST
542 && !TREE_OVERFLOW (t
))
545 else if (CP_INTEGRAL_TYPE_P (type
))
547 t
= fold_non_dependent_expr (t
);
549 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
556 /* Returns true iff T is a null member pointer value (4.11). */
559 null_member_pointer_value_p (tree t
)
561 tree type
= TREE_TYPE (t
);
564 else if (TYPE_PTRMEMFUNC_P (type
))
565 return (TREE_CODE (t
) == CONSTRUCTOR
566 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
567 else if (TYPE_PTRDATAMEM_P (type
))
568 return integer_all_onesp (t
);
573 /* Returns nonzero if PARMLIST consists of only default parms,
574 ellipsis, and/or undeduced parameter packs. */
577 sufficient_parms_p (const_tree parmlist
)
579 for (; parmlist
&& parmlist
!= void_list_node
;
580 parmlist
= TREE_CHAIN (parmlist
))
581 if (!TREE_PURPOSE (parmlist
)
582 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
587 /* Allocate N bytes of memory from the conversion obstack. The memory
588 is zeroed before being returned. */
591 conversion_obstack_alloc (size_t n
)
594 if (!conversion_obstack_initialized
)
596 gcc_obstack_init (&conversion_obstack
);
597 conversion_obstack_initialized
= true;
599 p
= obstack_alloc (&conversion_obstack
, n
);
604 /* Allocate rejection reasons. */
606 static struct rejection_reason
*
607 alloc_rejection (enum rejection_reason_code code
)
609 struct rejection_reason
*p
;
610 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
615 static struct rejection_reason
*
616 arity_rejection (tree first_arg
, int expected
, int actual
)
618 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
619 int adjust
= first_arg
!= NULL_TREE
;
620 r
->u
.arity
.expected
= expected
- adjust
;
621 r
->u
.arity
.actual
= actual
- adjust
;
625 static struct rejection_reason
*
626 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
)
628 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
629 int adjust
= first_arg
!= NULL_TREE
;
630 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
631 r
->u
.conversion
.from
= from
;
632 r
->u
.conversion
.to_type
= to
;
636 static struct rejection_reason
*
637 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
)
639 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
640 int adjust
= first_arg
!= NULL_TREE
;
641 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
642 r
->u
.bad_conversion
.from
= from
;
643 r
->u
.bad_conversion
.to_type
= to
;
647 static struct rejection_reason
*
648 explicit_conversion_rejection (tree from
, tree to
)
650 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
651 r
->u
.conversion
.n_arg
= 0;
652 r
->u
.conversion
.from
= from
;
653 r
->u
.conversion
.to_type
= to
;
657 static struct rejection_reason
*
658 template_conversion_rejection (tree from
, tree to
)
660 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
661 r
->u
.conversion
.n_arg
= 0;
662 r
->u
.conversion
.from
= from
;
663 r
->u
.conversion
.to_type
= to
;
667 static struct rejection_reason
*
668 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
669 const tree
*args
, unsigned int nargs
,
670 tree return_type
, unification_kind_t strict
,
673 size_t args_n_bytes
= sizeof (*args
) * nargs
;
674 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
675 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
676 r
->u
.template_unification
.tmpl
= tmpl
;
677 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
678 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
679 /* Copy args to our own storage. */
680 memcpy (args1
, args
, args_n_bytes
);
681 r
->u
.template_unification
.args
= args1
;
682 r
->u
.template_unification
.nargs
= nargs
;
683 r
->u
.template_unification
.return_type
= return_type
;
684 r
->u
.template_unification
.strict
= strict
;
685 r
->u
.template_unification
.flags
= flags
;
689 static struct rejection_reason
*
690 template_unification_error_rejection (void)
692 return alloc_rejection (rr_template_unification
);
695 static struct rejection_reason
*
696 invalid_copy_with_fn_template_rejection (void)
698 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
702 // Build a constraint failure record, saving information into the
703 // template_instantiation field of the rejection. If FN is not a template
704 // declaration, the TMPL member is the FN declaration and TARGS is empty.
706 static struct rejection_reason
*
707 constraint_failure (tree fn
)
709 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
710 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
712 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
713 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
717 r
->u
.template_instantiation
.tmpl
= fn
;
718 r
->u
.template_instantiation
.targs
= NULL_TREE
;
723 /* Dynamically allocate a conversion. */
726 alloc_conversion (conversion_kind kind
)
729 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
734 #ifdef ENABLE_CHECKING
736 /* Make sure that all memory on the conversion obstack has been
740 validate_conversion_obstack (void)
742 if (conversion_obstack_initialized
)
743 gcc_assert ((obstack_next_free (&conversion_obstack
)
744 == obstack_base (&conversion_obstack
)));
747 #endif /* ENABLE_CHECKING */
749 /* Dynamically allocate an array of N conversions. */
752 alloc_conversions (size_t n
)
754 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
758 build_conv (conversion_kind code
, tree type
, conversion
*from
)
761 conversion_rank rank
= CONVERSION_RANK (from
);
763 /* Note that the caller is responsible for filling in t->cand for
764 user-defined conversions. */
765 t
= alloc_conversion (code
);
788 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
789 t
->bad_p
= from
->bad_p
;
794 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
795 specialization of std::initializer_list<T>, if such a conversion is
799 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
801 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
802 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
803 conversion
**subconvs
= alloc_conversions (len
);
808 /* Within a list-initialization we can have more user-defined
810 flags
&= ~LOOKUP_NO_CONVERSION
;
811 /* But no narrowing conversions. */
812 flags
|= LOOKUP_NO_NARROWING
;
814 /* Can't make an array of these types. */
815 if (TREE_CODE (elttype
) == REFERENCE_TYPE
816 || TREE_CODE (elttype
) == FUNCTION_TYPE
817 || VOID_TYPE_P (elttype
))
820 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
823 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
824 false, flags
, complain
);
831 t
= alloc_conversion (ck_list
);
833 t
->u
.list
= subconvs
;
836 for (i
= 0; i
< len
; ++i
)
838 conversion
*sub
= subconvs
[i
];
839 if (sub
->rank
> t
->rank
)
841 if (sub
->user_conv_p
)
842 t
->user_conv_p
= true;
850 /* Return the next conversion of the conversion chain (if applicable),
851 or NULL otherwise. Please use this function instead of directly
852 accessing fields of struct conversion. */
855 next_conversion (conversion
*conv
)
858 || conv
->kind
== ck_identity
859 || conv
->kind
== ck_ambig
860 || conv
->kind
== ck_list
)
865 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
866 is a valid aggregate initializer for array type ATYPE. */
869 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
872 tree elttype
= TREE_TYPE (atype
);
873 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
875 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
877 if (TREE_CODE (elttype
) == ARRAY_TYPE
878 && TREE_CODE (val
) == CONSTRUCTOR
)
879 ok
= can_convert_array (elttype
, val
, flags
, complain
);
881 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
889 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
890 aggregate class, if such a conversion is possible. */
893 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
895 unsigned HOST_WIDE_INT i
= 0;
897 tree field
= next_initializable_field (TYPE_FIELDS (type
));
898 tree empty_ctor
= NULL_TREE
;
900 /* We already called reshape_init in implicit_conversion. */
902 /* The conversions within the init-list aren't affected by the enclosing
903 context; they're always simple copy-initialization. */
904 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
906 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
908 tree ftype
= TREE_TYPE (field
);
912 if (i
< CONSTRUCTOR_NELTS (ctor
))
913 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
914 else if (TREE_CODE (ftype
) == REFERENCE_TYPE
)
915 /* Value-initialization of reference is ill-formed. */
919 if (empty_ctor
== NULL_TREE
)
920 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
925 if (TREE_CODE (ftype
) == ARRAY_TYPE
926 && TREE_CODE (val
) == CONSTRUCTOR
)
927 ok
= can_convert_array (ftype
, val
, flags
, complain
);
929 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
935 if (TREE_CODE (type
) == UNION_TYPE
)
939 if (i
< CONSTRUCTOR_NELTS (ctor
))
942 c
= alloc_conversion (ck_aggr
);
945 c
->user_conv_p
= true;
946 c
->check_narrowing
= true;
951 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
952 array type, if such a conversion is possible. */
955 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
958 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
959 tree elttype
= TREE_TYPE (type
);
964 enum conversion_rank rank
= cr_exact
;
966 /* We might need to propagate the size from the element to the array. */
967 complete_type (type
);
969 if (TYPE_DOMAIN (type
)
970 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
972 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
977 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
979 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
982 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
983 false, flags
, complain
);
987 if (sub
->rank
> rank
)
989 if (sub
->user_conv_p
)
995 c
= alloc_conversion (ck_aggr
);
998 c
->user_conv_p
= user
;
1004 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1005 complex type, if such a conversion is possible. */
1008 build_complex_conv (tree type
, tree ctor
, int flags
,
1009 tsubst_flags_t complain
)
1012 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1013 tree elttype
= TREE_TYPE (type
);
1018 enum conversion_rank rank
= cr_exact
;
1023 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1025 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1028 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1029 false, flags
, complain
);
1033 if (sub
->rank
> rank
)
1035 if (sub
->user_conv_p
)
1041 c
= alloc_conversion (ck_aggr
);
1044 c
->user_conv_p
= user
;
1050 /* Build a representation of the identity conversion from EXPR to
1051 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1054 build_identity_conv (tree type
, tree expr
)
1058 c
= alloc_conversion (ck_identity
);
1065 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1066 were multiple user-defined conversions to accomplish the job.
1067 Build a conversion that indicates that ambiguity. */
1070 build_ambiguous_conv (tree type
, tree expr
)
1074 c
= alloc_conversion (ck_ambig
);
1082 strip_top_quals (tree t
)
1084 if (TREE_CODE (t
) == ARRAY_TYPE
)
1086 return cp_build_qualified_type (t
, 0);
1089 /* Returns the standard conversion path (see [conv]) from type FROM to type
1090 TO, if any. For proper handling of null pointer constants, you must
1091 also pass the expression EXPR to convert from. If C_CAST_P is true,
1092 this conversion is coming from a C-style cast. */
1095 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1098 enum tree_code fcode
, tcode
;
1100 bool fromref
= false;
1103 to
= non_reference (to
);
1104 if (TREE_CODE (from
) == REFERENCE_TYPE
)
1107 from
= TREE_TYPE (from
);
1110 to
= strip_top_quals (to
);
1111 from
= strip_top_quals (from
);
1113 if (expr
&& type_unknown_p (expr
))
1115 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1117 tsubst_flags_t tflags
= tf_conv
;
1118 expr
= instantiate_type (to
, expr
, tflags
);
1119 if (expr
== error_mark_node
)
1121 from
= TREE_TYPE (expr
);
1123 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1125 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1126 expr
= resolve_nondeduced_context (expr
);
1127 from
= TREE_TYPE (expr
);
1131 fcode
= TREE_CODE (from
);
1132 tcode
= TREE_CODE (to
);
1134 conv
= build_identity_conv (from
, expr
);
1135 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1137 from
= type_decays_to (from
);
1138 fcode
= TREE_CODE (from
);
1139 conv
= build_conv (ck_lvalue
, from
, conv
);
1141 else if (fromref
|| (expr
&& lvalue_p (expr
)))
1146 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1149 from
= strip_top_quals (bitfield_type
);
1150 fcode
= TREE_CODE (from
);
1153 conv
= build_conv (ck_rvalue
, from
, conv
);
1154 if (flags
& LOOKUP_PREFER_RVALUE
)
1155 conv
->rvaluedness_matches_p
= true;
1158 /* Allow conversion between `__complex__' data types. */
1159 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1161 /* The standard conversion sequence to convert FROM to TO is
1162 the standard conversion sequence to perform componentwise
1164 conversion
*part_conv
= standard_conversion
1165 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
);
1169 conv
= build_conv (part_conv
->kind
, to
, conv
);
1170 conv
->rank
= part_conv
->rank
;
1178 if (same_type_p (from
, to
))
1180 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1181 conv
->type
= qualified_to
;
1186 A null pointer constant can be converted to a pointer type; ... A
1187 null pointer constant of integral type can be converted to an
1188 rvalue of type std::nullptr_t. */
1189 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1190 || NULLPTR_TYPE_P (to
))
1191 && ((expr
&& null_ptr_cst_p (expr
))
1192 || NULLPTR_TYPE_P (from
)))
1193 conv
= build_conv (ck_std
, to
, conv
);
1194 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1195 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1197 /* For backwards brain damage compatibility, allow interconversion of
1198 pointers and integers with a pedwarn. */
1199 conv
= build_conv (ck_std
, to
, conv
);
1202 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1204 /* For backwards brain damage compatibility, allow interconversion of
1205 enums and integers with a pedwarn. */
1206 conv
= build_conv (ck_std
, to
, conv
);
1209 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1210 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1215 if (tcode
== POINTER_TYPE
1216 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from
),
1219 else if (VOID_TYPE_P (TREE_TYPE (to
))
1220 && !TYPE_PTRDATAMEM_P (from
)
1221 && TREE_CODE (TREE_TYPE (from
)) != FUNCTION_TYPE
)
1223 tree nfrom
= TREE_TYPE (from
);
1224 /* Don't try to apply restrict to void. */
1225 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1226 from
= build_pointer_type
1227 (cp_build_qualified_type (void_type_node
, quals
));
1228 conv
= build_conv (ck_ptr
, from
, conv
);
1230 else if (TYPE_PTRDATAMEM_P (from
))
1232 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1233 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1235 if (DERIVED_FROM_P (fbase
, tbase
)
1236 && (same_type_ignoring_top_level_qualifiers_p
1237 (TYPE_PTRMEM_POINTED_TO_TYPE (from
),
1238 TYPE_PTRMEM_POINTED_TO_TYPE (to
))))
1240 from
= build_ptrmem_type (tbase
,
1241 TYPE_PTRMEM_POINTED_TO_TYPE (from
));
1242 conv
= build_conv (ck_pmem
, from
, conv
);
1244 else if (!same_type_p (fbase
, tbase
))
1247 else if (CLASS_TYPE_P (TREE_TYPE (from
))
1248 && CLASS_TYPE_P (TREE_TYPE (to
))
1251 An rvalue of type "pointer to cv D," where D is a
1252 class type, can be converted to an rvalue of type
1253 "pointer to cv B," where B is a base class (clause
1254 _class.derived_) of D. If B is an inaccessible
1255 (clause _class.access_) or ambiguous
1256 (_class.member.lookup_) base class of D, a program
1257 that necessitates this conversion is ill-formed.
1258 Therefore, we use DERIVED_FROM_P, and do not check
1259 access or uniqueness. */
1260 && DERIVED_FROM_P (TREE_TYPE (to
), TREE_TYPE (from
)))
1263 cp_build_qualified_type (TREE_TYPE (to
),
1264 cp_type_quals (TREE_TYPE (from
)));
1265 from
= build_pointer_type (from
);
1266 conv
= build_conv (ck_ptr
, from
, conv
);
1267 conv
->base_p
= true;
1269 else if (tx_safe_fn_type_p (TREE_TYPE (from
)))
1271 /* A prvalue of type "pointer to transaction_safe function" can be
1272 converted to a prvalue of type "pointer to function". */
1273 tree unsafe
= tx_unsafe_fn_variant (TREE_TYPE (from
));
1274 if (same_type_p (unsafe
, TREE_TYPE (to
)))
1276 from
= build_pointer_type (unsafe
);
1277 conv
= build_conv (ck_tsafe
, from
, conv
);
1281 if (tcode
== POINTER_TYPE
)
1283 to_pointee
= TREE_TYPE (to
);
1284 from_pointee
= TREE_TYPE (from
);
1288 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1289 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1292 if (same_type_p (from
, to
))
1294 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1295 /* In a C-style cast, we ignore CV-qualification because we
1296 are allowed to perform a static_cast followed by a
1298 conv
= build_conv (ck_qual
, to
, conv
);
1299 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1300 conv
= build_conv (ck_qual
, to
, conv
);
1301 else if (expr
&& string_conv_p (to
, expr
, 0))
1302 /* converting from string constant to char *. */
1303 conv
= build_conv (ck_qual
, to
, conv
);
1304 /* Allow conversions among compatible ObjC pointer types (base
1305 conversions have been already handled above). */
1306 else if (c_dialect_objc ()
1307 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1308 conv
= build_conv (ck_ptr
, to
, conv
);
1309 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1311 conv
= build_conv (ck_ptr
, to
, conv
);
1319 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1321 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1322 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1323 tree fbase
= class_of_this_parm (fromfn
);
1324 tree tbase
= class_of_this_parm (tofn
);
1326 if (!DERIVED_FROM_P (fbase
, tbase
)
1327 || !same_type_p (static_fn_type (fromfn
),
1328 static_fn_type (tofn
)))
1331 from
= build_memfn_type (fromfn
,
1333 cp_type_quals (tbase
),
1334 type_memfn_rqual (tofn
));
1335 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1336 conv
= build_conv (ck_pmem
, from
, conv
);
1337 conv
->base_p
= true;
1339 else if (tcode
== BOOLEAN_TYPE
)
1343 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1344 to member type can be converted to a prvalue of type bool. ...
1345 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1346 std::nullptr_t can be converted to a prvalue of type bool; */
1347 if (ARITHMETIC_TYPE_P (from
)
1348 || UNSCOPED_ENUM_P (from
)
1349 || fcode
== POINTER_TYPE
1350 || TYPE_PTRMEM_P (from
)
1351 || NULLPTR_TYPE_P (from
))
1353 conv
= build_conv (ck_std
, to
, conv
);
1354 if (fcode
== POINTER_TYPE
1355 || TYPE_PTRDATAMEM_P (from
)
1356 || (TYPE_PTRMEMFUNC_P (from
)
1357 && conv
->rank
< cr_pbool
)
1358 || NULLPTR_TYPE_P (from
))
1359 conv
->rank
= cr_pbool
;
1360 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1367 /* We don't check for ENUMERAL_TYPE here because there are no standard
1368 conversions to enum type. */
1369 /* As an extension, allow conversion to complex type. */
1370 else if (ARITHMETIC_TYPE_P (to
))
1372 if (! (INTEGRAL_CODE_P (fcode
)
1373 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1374 || SCOPED_ENUM_P (from
))
1376 conv
= build_conv (ck_std
, to
, conv
);
1378 /* Give this a better rank if it's a promotion. */
1379 if (same_type_p (to
, type_promotes_to (from
))
1380 && next_conversion (conv
)->rank
<= cr_promotion
)
1381 conv
->rank
= cr_promotion
;
1383 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1384 && vector_types_convertible_p (from
, to
, false))
1385 return build_conv (ck_std
, to
, conv
);
1386 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1387 && is_properly_derived_from (from
, to
))
1389 if (conv
->kind
== ck_rvalue
)
1390 conv
= next_conversion (conv
);
1391 conv
= build_conv (ck_base
, to
, conv
);
1392 /* The derived-to-base conversion indicates the initialization
1393 of a parameter with base type from an object of a derived
1394 type. A temporary object is created to hold the result of
1395 the conversion unless we're binding directly to a reference. */
1396 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1401 if (flags
& LOOKUP_NO_NARROWING
)
1402 conv
->check_narrowing
= true;
1407 /* Returns nonzero if T1 is reference-related to T2. */
1410 reference_related_p (tree t1
, tree t2
)
1412 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1415 t1
= TYPE_MAIN_VARIANT (t1
);
1416 t2
= TYPE_MAIN_VARIANT (t2
);
1420 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1421 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1423 return (same_type_p (t1
, t2
)
1424 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1425 && DERIVED_FROM_P (t1
, t2
)));
1428 /* Returns nonzero if T1 is reference-compatible with T2. */
1431 reference_compatible_p (tree t1
, tree t2
)
1435 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1436 reference-related to T2 and cv1 is the same cv-qualification as,
1437 or greater cv-qualification than, cv2. */
1438 return (reference_related_p (t1
, t2
)
1439 && at_least_as_qualified_p (t1
, t2
));
1442 /* A reference of the indicated TYPE is being bound directly to the
1443 expression represented by the implicit conversion sequence CONV.
1444 Return a conversion sequence for this binding. */
1447 direct_reference_binding (tree type
, conversion
*conv
)
1451 gcc_assert (TREE_CODE (type
) == REFERENCE_TYPE
);
1452 gcc_assert (TREE_CODE (conv
->type
) != REFERENCE_TYPE
);
1454 t
= TREE_TYPE (type
);
1458 When a parameter of reference type binds directly
1459 (_dcl.init.ref_) to an argument expression, the implicit
1460 conversion sequence is the identity conversion, unless the
1461 argument expression has a type that is a derived class of the
1462 parameter type, in which case the implicit conversion sequence is
1463 a derived-to-base Conversion.
1465 If the parameter binds directly to the result of applying a
1466 conversion function to the argument expression, the implicit
1467 conversion sequence is a user-defined conversion sequence
1468 (_over.ics.user_), with the second standard conversion sequence
1469 either an identity conversion or, if the conversion function
1470 returns an entity of a type that is a derived class of the
1471 parameter type, a derived-to-base conversion. */
1472 if (!same_type_ignoring_top_level_qualifiers_p (t
, conv
->type
))
1474 /* Represent the derived-to-base conversion. */
1475 conv
= build_conv (ck_base
, t
, conv
);
1476 /* We will actually be binding to the base-class subobject in
1477 the derived class, so we mark this conversion appropriately.
1478 That way, convert_like knows not to generate a temporary. */
1479 conv
->need_temporary_p
= false;
1481 return build_conv (ck_ref_bind
, type
, conv
);
1484 /* Returns the conversion path from type FROM to reference type TO for
1485 purposes of reference binding. For lvalue binding, either pass a
1486 reference type to FROM or an lvalue expression to EXPR. If the
1487 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1488 the conversion returned. If C_CAST_P is true, this
1489 conversion is coming from a C-style cast. */
1492 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1493 tsubst_flags_t complain
)
1495 conversion
*conv
= NULL
;
1496 tree to
= TREE_TYPE (rto
);
1501 cp_lvalue_kind gl_kind
;
1504 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1506 expr
= instantiate_type (to
, expr
, tf_none
);
1507 if (expr
== error_mark_node
)
1509 from
= TREE_TYPE (expr
);
1512 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1514 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1515 /* DR 1288: Otherwise, if the initializer list has a single element
1516 of type E and ... [T's] referenced type is reference-related to E,
1517 the object or reference is initialized from that element... */
1518 if (CONSTRUCTOR_NELTS (expr
) == 1)
1520 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1521 if (error_operand_p (elt
))
1523 tree etype
= TREE_TYPE (elt
);
1524 if (reference_related_p (to
, etype
))
1531 /* Otherwise, if T is a reference type, a prvalue temporary of the
1532 type referenced by T is copy-list-initialized or
1533 direct-list-initialized, depending on the kind of initialization
1534 for the reference, and the reference is bound to that temporary. */
1535 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1536 flags
|LOOKUP_NO_TEMP_BIND
, complain
);
1540 if (TREE_CODE (from
) == REFERENCE_TYPE
)
1542 from
= TREE_TYPE (from
);
1543 if (!TYPE_REF_IS_RVALUE (rfrom
)
1544 || TREE_CODE (from
) == FUNCTION_TYPE
)
1545 gl_kind
= clk_ordinary
;
1547 gl_kind
= clk_rvalueref
;
1551 gl_kind
= lvalue_kind (expr
);
1552 if (gl_kind
& clk_class
)
1553 /* A class prvalue is not a glvalue. */
1558 is_lvalue
= gl_kind
&& !(gl_kind
& clk_rvalueref
);
1561 if ((gl_kind
& clk_bitfield
) != 0)
1562 tfrom
= unlowered_expr_type (expr
);
1564 /* Figure out whether or not the types are reference-related and
1565 reference compatible. We have to do this after stripping
1566 references from FROM. */
1567 related_p
= reference_related_p (to
, tfrom
);
1568 /* If this is a C cast, first convert to an appropriately qualified
1569 type, so that we can later do a const_cast to the desired type. */
1570 if (related_p
&& c_cast_p
1571 && !at_least_as_qualified_p (to
, tfrom
))
1572 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1573 compatible_p
= reference_compatible_p (to
, tfrom
);
1575 /* Directly bind reference when target expression's type is compatible with
1576 the reference and expression is an lvalue. In DR391, the wording in
1577 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1578 const and rvalue references to rvalues of compatible class type.
1579 We should also do direct bindings for non-class xvalues. */
1582 || (!(flags
& LOOKUP_NO_TEMP_BIND
)
1583 && (CLASS_TYPE_P (from
)
1584 || TREE_CODE (from
) == ARRAY_TYPE
))))
1588 If the initializer expression
1590 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1591 is reference-compatible with "cv2 T2,"
1593 the reference is bound directly to the initializer expression
1597 If the initializer expression is an rvalue, with T2 a class type,
1598 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1599 is bound to the object represented by the rvalue or to a sub-object
1600 within that object. */
1602 conv
= build_identity_conv (tfrom
, expr
);
1603 conv
= direct_reference_binding (rto
, conv
);
1605 if (flags
& LOOKUP_PREFER_RVALUE
)
1606 /* The top-level caller requested that we pretend that the lvalue
1607 be treated as an rvalue. */
1608 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1609 else if (TREE_CODE (rfrom
) == REFERENCE_TYPE
)
1610 /* Handle rvalue reference to function properly. */
1611 conv
->rvaluedness_matches_p
1612 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1614 conv
->rvaluedness_matches_p
1615 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1617 if ((gl_kind
& clk_bitfield
) != 0
1618 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1619 /* For the purposes of overload resolution, we ignore the fact
1620 this expression is a bitfield or packed field. (In particular,
1621 [over.ics.ref] says specifically that a function with a
1622 non-const reference parameter is viable even if the
1623 argument is a bitfield.)
1625 However, when we actually call the function we must create
1626 a temporary to which to bind the reference. If the
1627 reference is volatile, or isn't const, then we cannot make
1628 a temporary, so we just issue an error when the conversion
1630 conv
->need_temporary_p
= true;
1632 /* Don't allow binding of lvalues (other than function lvalues) to
1633 rvalue references. */
1634 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1635 && TREE_CODE (to
) != FUNCTION_TYPE
1636 && !(flags
& LOOKUP_PREFER_RVALUE
))
1639 /* Nor the reverse. */
1640 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1641 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1642 || (flags
& LOOKUP_NO_RVAL_BIND
))
1643 && TREE_CODE (to
) != FUNCTION_TYPE
)
1651 /* [class.conv.fct] A conversion function is never used to convert a
1652 (possibly cv-qualified) object to the (possibly cv-qualified) same
1653 object type (or a reference to it), to a (possibly cv-qualified) base
1654 class of that type (or a reference to it).... */
1655 else if (CLASS_TYPE_P (from
) && !related_p
1656 && !(flags
& LOOKUP_NO_CONVERSION
))
1660 If the initializer expression
1662 -- has a class type (i.e., T2 is a class type) can be
1663 implicitly converted to an lvalue of type "cv3 T3," where
1664 "cv1 T1" is reference-compatible with "cv3 T3". (this
1665 conversion is selected by enumerating the applicable
1666 conversion functions (_over.match.ref_) and choosing the
1667 best one through overload resolution. (_over.match_).
1669 the reference is bound to the lvalue result of the conversion
1670 in the second case. */
1671 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1674 return cand
->second_conv
;
1677 /* From this point on, we conceptually need temporaries, even if we
1678 elide them. Only the cases above are "direct bindings". */
1679 if (flags
& LOOKUP_NO_TEMP_BIND
)
1684 When a parameter of reference type is not bound directly to an
1685 argument expression, the conversion sequence is the one required
1686 to convert the argument expression to the underlying type of the
1687 reference according to _over.best.ics_. Conceptually, this
1688 conversion sequence corresponds to copy-initializing a temporary
1689 of the underlying type with the argument expression. Any
1690 difference in top-level cv-qualification is subsumed by the
1691 initialization itself and does not constitute a conversion. */
1695 Otherwise, the reference shall be an lvalue reference to a
1696 non-volatile const type, or the reference shall be an rvalue
1699 We try below to treat this as a bad conversion to improve diagnostics,
1700 but if TO is an incomplete class, we need to reject this conversion
1701 now to avoid unnecessary instantiation. */
1702 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1703 && !COMPLETE_TYPE_P (to
))
1706 /* We're generating a temporary now, but don't bind any more in the
1707 conversion (specifically, don't slice the temporary returned by a
1708 conversion operator). */
1709 flags
|= LOOKUP_NO_TEMP_BIND
;
1711 /* Core issue 899: When [copy-]initializing a temporary to be bound
1712 to the first parameter of a copy constructor (12.8) called with
1713 a single argument in the context of direct-initialization,
1714 explicit conversion functions are also considered.
1716 So don't set LOOKUP_ONLYCONVERTING in that case. */
1717 if (!(flags
& LOOKUP_COPY_PARM
))
1718 flags
|= LOOKUP_ONLYCONVERTING
;
1721 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1726 if (conv
->user_conv_p
)
1728 /* If initializing the temporary used a conversion function,
1729 recalculate the second conversion sequence. */
1730 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1731 if (t
->kind
== ck_user
1732 && DECL_CONV_FN_P (t
->cand
->fn
))
1734 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1735 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1736 conversion
*new_second
1737 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1741 return merge_conversion_sequences (t
, new_second
);
1745 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1746 /* This reference binding, unlike those above, requires the
1747 creation of a temporary. */
1748 conv
->need_temporary_p
= true;
1749 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1753 Otherwise, the reference shall be an lvalue reference to a
1754 non-volatile const type, or the reference shall be an rvalue
1756 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1761 Otherwise, a temporary of type "cv1 T1" is created and
1762 initialized from the initializer expression using the rules for a
1763 non-reference copy initialization. If T1 is reference-related to
1764 T2, cv1 must be the same cv-qualification as, or greater
1765 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1766 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1772 /* Returns the implicit conversion sequence (see [over.ics]) from type
1773 FROM to type TO. The optional expression EXPR may affect the
1774 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1775 true, this conversion is coming from a C-style cast. */
1778 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1779 int flags
, tsubst_flags_t complain
)
1783 if (from
== error_mark_node
|| to
== error_mark_node
1784 || expr
== error_mark_node
)
1787 /* Other flags only apply to the primary function in overload
1788 resolution, or after we've chosen one. */
1789 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1790 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1791 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1793 /* FIXME: actually we don't want warnings either, but we can't just
1794 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1795 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1796 We really ought not to issue that warning until we've committed
1797 to that conversion. */
1798 complain
&= ~tf_error
;
1800 /* Call reshape_init early to remove redundant braces. */
1801 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1802 && CLASS_TYPE_P (to
)
1803 && COMPLETE_TYPE_P (complete_type (to
))
1804 && !CLASSTYPE_NON_AGGREGATE (to
))
1806 expr
= reshape_init (to
, expr
, complain
);
1807 if (expr
== error_mark_node
)
1809 from
= TREE_TYPE (expr
);
1812 if (TREE_CODE (to
) == REFERENCE_TYPE
)
1813 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1815 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
);
1820 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1822 if (is_std_init_list (to
))
1823 return build_list_conv (to
, expr
, flags
, complain
);
1825 /* As an extension, allow list-initialization of _Complex. */
1826 if (TREE_CODE (to
) == COMPLEX_TYPE
)
1828 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1833 /* Allow conversion from an initializer-list with one element to a
1835 if (SCALAR_TYPE_P (to
))
1837 int nelts
= CONSTRUCTOR_NELTS (expr
);
1841 elt
= build_value_init (to
, tf_none
);
1842 else if (nelts
== 1)
1843 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1845 elt
= error_mark_node
;
1847 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1848 c_cast_p
, flags
, complain
);
1851 conv
->check_narrowing
= true;
1852 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1853 /* Too many levels of braces, i.e. '{{1}}'. */
1858 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1859 return build_array_conv (to
, expr
, flags
, complain
);
1862 if (expr
!= NULL_TREE
1863 && (MAYBE_CLASS_TYPE_P (from
)
1864 || MAYBE_CLASS_TYPE_P (to
))
1865 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1867 struct z_candidate
*cand
;
1869 if (CLASS_TYPE_P (to
)
1870 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1871 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1872 return build_aggr_conv (to
, expr
, flags
, complain
);
1874 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
1876 conv
= cand
->second_conv
;
1878 /* We used to try to bind a reference to a temporary here, but that
1879 is now handled after the recursive call to this function at the end
1880 of reference_binding. */
1887 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1888 functions. ARGS will not be changed until a single candidate is
1891 static struct z_candidate
*
1892 add_candidate (struct z_candidate
**candidates
,
1893 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
1894 size_t num_convs
, conversion
**convs
,
1895 tree access_path
, tree conversion_path
,
1896 int viable
, struct rejection_reason
*reason
,
1899 struct z_candidate
*cand
= (struct z_candidate
*)
1900 conversion_obstack_alloc (sizeof (struct z_candidate
));
1903 cand
->first_arg
= first_arg
;
1905 cand
->convs
= convs
;
1906 cand
->num_convs
= num_convs
;
1907 cand
->access_path
= access_path
;
1908 cand
->conversion_path
= conversion_path
;
1909 cand
->viable
= viable
;
1910 cand
->reason
= reason
;
1911 cand
->next
= *candidates
;
1912 cand
->flags
= flags
;
1918 /* Return the number of remaining arguments in the parameter list
1919 beginning with ARG. */
1922 remaining_arguments (tree arg
)
1926 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
1927 arg
= TREE_CHAIN (arg
))
1933 /* Create an overload candidate for the function or method FN called
1934 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1935 FLAGS is passed on to implicit_conversion.
1937 This does not change ARGS.
1939 CTYPE, if non-NULL, is the type we want to pretend this function
1940 comes from for purposes of overload resolution. */
1942 static struct z_candidate
*
1943 add_function_candidate (struct z_candidate
**candidates
,
1944 tree fn
, tree ctype
, tree first_arg
,
1945 const vec
<tree
, va_gc
> *args
, tree access_path
,
1946 tree conversion_path
, int flags
,
1947 tsubst_flags_t complain
)
1949 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
1953 tree orig_first_arg
= first_arg
;
1956 struct rejection_reason
*reason
= NULL
;
1958 /* At this point we should not see any functions which haven't been
1959 explicitly declared, except for friend functions which will have
1960 been found using argument dependent lookup. */
1961 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
1963 /* The `this', `in_chrg' and VTT arguments to constructors are not
1964 considered in overload resolution. */
1965 if (DECL_CONSTRUCTOR_P (fn
))
1967 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
1968 skip
= num_artificial_parms_for (fn
);
1969 if (skip
> 0 && first_arg
!= NULL_TREE
)
1972 first_arg
= NULL_TREE
;
1978 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
1979 convs
= alloc_conversions (len
);
1981 /* 13.3.2 - Viable functions [over.match.viable]
1982 First, to be a viable function, a candidate function shall have enough
1983 parameters to agree in number with the arguments in the list.
1985 We need to check this first; otherwise, checking the ICSes might cause
1986 us to produce an ill-formed template instantiation. */
1988 parmnode
= parmlist
;
1989 for (i
= 0; i
< len
; ++i
)
1991 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
1993 parmnode
= TREE_CHAIN (parmnode
);
1996 if ((i
< len
&& parmnode
)
1997 || !sufficient_parms_p (parmnode
))
1999 int remaining
= remaining_arguments (parmnode
);
2001 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2004 /* Second, for a function to be viable, its constraints must be
2006 if (flag_concepts
&& viable
2007 && !constraints_satisfied_p (fn
))
2009 reason
= constraint_failure (fn
);
2013 /* When looking for a function from a subobject from an implicit
2014 copy/move constructor/operator=, don't consider anything that takes (a
2015 reference to) an unrelated type. See c++/44909 and core 1092. */
2016 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2018 if (DECL_CONSTRUCTOR_P (fn
))
2020 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2021 && DECL_OVERLOADED_OPERATOR_P (fn
) == NOP_EXPR
)
2027 parmnode
= chain_index (i
-1, parmlist
);
2028 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2033 /* This only applies at the top level. */
2034 flags
&= ~LOOKUP_DEFAULTED
;
2040 /* Third, for F to be a viable function, there shall exist for each
2041 argument an implicit conversion sequence that converts that argument
2042 to the corresponding parameter of F. */
2044 parmnode
= parmlist
;
2046 for (i
= 0; i
< len
; ++i
)
2048 tree argtype
, to_type
;
2053 if (parmnode
== void_list_node
)
2056 if (i
== 0 && first_arg
!= NULL_TREE
)
2059 arg
= CONST_CAST_TREE (
2060 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2061 argtype
= lvalue_type (arg
);
2063 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2064 && ! DECL_CONSTRUCTOR_P (fn
));
2068 tree parmtype
= TREE_VALUE (parmnode
);
2071 parmnode
= TREE_CHAIN (parmnode
);
2073 /* The type of the implicit object parameter ('this') for
2074 overload resolution is not always the same as for the
2075 function itself; conversion functions are considered to
2076 be members of the class being converted, and functions
2077 introduced by a using-declaration are considered to be
2078 members of the class that uses them.
2080 Since build_over_call ignores the ICS for the `this'
2081 parameter, we can just change the parm type. */
2082 if (ctype
&& is_this
)
2084 parmtype
= cp_build_qualified_type
2085 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2086 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2088 /* If the function has a ref-qualifier, the implicit
2089 object parameter has reference type. */
2090 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2091 parmtype
= cp_build_reference_type (parmtype
, rv
);
2092 /* The special handling of 'this' conversions in compare_ics
2093 does not apply if there is a ref-qualifier. */
2098 parmtype
= build_pointer_type (parmtype
);
2099 arg
= build_this (arg
);
2100 argtype
= lvalue_type (arg
);
2104 /* Core issue 899: When [copy-]initializing a temporary to be bound
2105 to the first parameter of a copy constructor (12.8) called with
2106 a single argument in the context of direct-initialization,
2107 explicit conversion functions are also considered.
2109 So set LOOKUP_COPY_PARM to let reference_binding know that
2110 it's being called in that context. We generalize the above
2111 to handle move constructors and template constructors as well;
2112 the standardese should soon be updated similarly. */
2113 if (ctype
&& i
== 0 && (len
-skip
== 1)
2114 && DECL_CONSTRUCTOR_P (fn
)
2115 && parmtype
!= error_mark_node
2116 && (same_type_ignoring_top_level_qualifiers_p
2117 (non_reference (parmtype
), ctype
)))
2119 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2120 lflags
|= LOOKUP_COPY_PARM
;
2121 /* We allow user-defined conversions within init-lists, but
2122 don't list-initialize the copy parm, as that would mean
2123 using two levels of braces for the same type. */
2124 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2125 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2126 lflags
|= LOOKUP_NO_CONVERSION
;
2129 lflags
|= LOOKUP_ONLYCONVERTING
;
2131 t
= implicit_conversion (parmtype
, argtype
, arg
,
2132 /*c_cast_p=*/false, lflags
, complain
);
2137 t
= build_identity_conv (argtype
, arg
);
2138 t
->ellipsis_p
= true;
2149 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
);
2156 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
);
2161 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2162 access_path
, conversion_path
, viable
, reason
, flags
);
2165 /* Create an overload candidate for the conversion function FN which will
2166 be invoked for expression OBJ, producing a pointer-to-function which
2167 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2168 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2169 passed on to implicit_conversion.
2171 Actually, we don't really care about FN; we care about the type it
2172 converts to. There may be multiple conversion functions that will
2173 convert to that type, and we rely on build_user_type_conversion_1 to
2174 choose the best one; so when we create our candidate, we record the type
2175 instead of the function. */
2177 static struct z_candidate
*
2178 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2179 tree first_arg
, const vec
<tree
, va_gc
> *arglist
,
2180 tree access_path
, tree conversion_path
,
2181 tsubst_flags_t complain
)
2183 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2184 int i
, len
, viable
, flags
;
2185 tree parmlist
, parmnode
;
2187 struct rejection_reason
*reason
;
2189 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2190 parmlist
= TREE_TYPE (parmlist
);
2191 parmlist
= TYPE_ARG_TYPES (parmlist
);
2193 len
= vec_safe_length (arglist
) + (first_arg
!= NULL_TREE
? 1 : 0) + 1;
2194 convs
= alloc_conversions (len
);
2195 parmnode
= parmlist
;
2197 flags
= LOOKUP_IMPLICIT
;
2200 /* Don't bother looking up the same type twice. */
2201 if (*candidates
&& (*candidates
)->fn
== totype
)
2204 for (i
= 0; i
< len
; ++i
)
2206 tree arg
, argtype
, convert_type
= NULL_TREE
;
2211 else if (i
== 1 && first_arg
!= NULL_TREE
)
2214 arg
= (*arglist
)[i
- (first_arg
!= NULL_TREE
? 1 : 0) - 1];
2215 argtype
= lvalue_type (arg
);
2219 t
= implicit_conversion (totype
, argtype
, arg
, /*c_cast_p=*/false,
2221 convert_type
= totype
;
2223 else if (parmnode
== void_list_node
)
2227 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2228 /*c_cast_p=*/false, flags
, complain
);
2229 convert_type
= TREE_VALUE (parmnode
);
2233 t
= build_identity_conv (argtype
, arg
);
2234 t
->ellipsis_p
= true;
2235 convert_type
= argtype
;
2245 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
);
2252 parmnode
= TREE_CHAIN (parmnode
);
2256 || ! sufficient_parms_p (parmnode
))
2258 int remaining
= remaining_arguments (parmnode
);
2260 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2263 return add_candidate (candidates
, totype
, first_arg
, arglist
, len
, convs
,
2264 access_path
, conversion_path
, viable
, reason
, flags
);
2268 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2269 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2270 int flags
, tsubst_flags_t complain
)
2277 struct rejection_reason
*reason
= NULL
;
2282 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2283 convs
= alloc_conversions (num_convs
);
2285 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2286 conversion ops are allowed. We handle that here by just checking for
2287 boolean_type_node because other operators don't ask for it. COND_EXPR
2288 also does contextual conversion to bool for the first operand, but we
2289 handle that in build_conditional_expr, and type1 here is operand 2. */
2290 if (type1
!= boolean_type_node
)
2291 flags
|= LOOKUP_ONLYCONVERTING
;
2293 for (i
= 0; i
< 2; ++i
)
2298 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2299 /*c_cast_p=*/false, flags
, complain
);
2303 /* We need something for printing the candidate. */
2304 t
= build_identity_conv (types
[i
], NULL_TREE
);
2305 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2311 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2317 /* For COND_EXPR we rearranged the arguments; undo that now. */
2320 convs
[2] = convs
[1];
2321 convs
[1] = convs
[0];
2322 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2323 /*c_cast_p=*/false, flags
,
2330 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2335 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2337 /*access_path=*/NULL_TREE
,
2338 /*conversion_path=*/NULL_TREE
,
2339 viable
, reason
, flags
);
2343 is_complete (tree t
)
2345 return COMPLETE_TYPE_P (complete_type (t
));
2348 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2351 promoted_arithmetic_type_p (tree type
)
2355 In this section, the term promoted integral type is used to refer
2356 to those integral types which are preserved by integral promotion
2357 (including e.g. int and long but excluding e.g. char).
2358 Similarly, the term promoted arithmetic type refers to promoted
2359 integral types plus floating types. */
2360 return ((CP_INTEGRAL_TYPE_P (type
)
2361 && same_type_p (type_promotes_to (type
), type
))
2362 || TREE_CODE (type
) == REAL_TYPE
);
2365 /* Create any builtin operator overload candidates for the operator in
2366 question given the converted operand types TYPE1 and TYPE2. The other
2367 args are passed through from add_builtin_candidates to
2368 build_builtin_candidate.
2370 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2371 If CODE is requires candidates operands of the same type of the kind
2372 of which TYPE1 and TYPE2 are, we add both candidates
2373 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2376 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2377 enum tree_code code2
, tree fnname
, tree type1
,
2378 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2379 tsubst_flags_t complain
)
2383 case POSTINCREMENT_EXPR
:
2384 case POSTDECREMENT_EXPR
:
2385 args
[1] = integer_zero_node
;
2386 type2
= integer_type_node
;
2395 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2396 and VQ is either volatile or empty, there exist candidate operator
2397 functions of the form
2398 VQ T& operator++(VQ T&);
2399 T operator++(VQ T&, int);
2400 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2401 type other than bool, and VQ is either volatile or empty, there exist
2402 candidate operator functions of the form
2403 VQ T& operator--(VQ T&);
2404 T operator--(VQ T&, int);
2405 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2406 complete object type, and VQ is either volatile or empty, there exist
2407 candidate operator functions of the form
2408 T*VQ& operator++(T*VQ&);
2409 T*VQ& operator--(T*VQ&);
2410 T* operator++(T*VQ&, int);
2411 T* operator--(T*VQ&, int); */
2413 case POSTDECREMENT_EXPR
:
2414 case PREDECREMENT_EXPR
:
2415 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2417 case POSTINCREMENT_EXPR
:
2418 case PREINCREMENT_EXPR
:
2419 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2421 type1
= build_reference_type (type1
);
2426 /* 7 For every cv-qualified or cv-unqualified object type T, there
2427 exist candidate operator functions of the form
2431 8 For every function type T, there exist candidate operator functions of
2433 T& operator*(T*); */
2436 if (TYPE_PTR_P (type1
)
2437 && (TYPE_PTROB_P (type1
)
2438 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2442 /* 9 For every type T, there exist candidate operator functions of the form
2445 10For every promoted arithmetic type T, there exist candidate operator
2446 functions of the form
2450 case UNARY_PLUS_EXPR
: /* unary + */
2451 if (TYPE_PTR_P (type1
))
2454 if (ARITHMETIC_TYPE_P (type1
))
2458 /* 11For every promoted integral type T, there exist candidate operator
2459 functions of the form
2463 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2467 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2468 is the same type as C2 or is a derived class of C2, T is a complete
2469 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2470 there exist candidate operator functions of the form
2471 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2472 where CV12 is the union of CV1 and CV2. */
2475 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2477 tree c1
= TREE_TYPE (type1
);
2478 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2480 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2481 && (TYPE_PTRMEMFUNC_P (type2
)
2482 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2487 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2488 didate operator functions of the form
2493 bool operator<(L, R);
2494 bool operator>(L, R);
2495 bool operator<=(L, R);
2496 bool operator>=(L, R);
2497 bool operator==(L, R);
2498 bool operator!=(L, R);
2499 where LR is the result of the usual arithmetic conversions between
2502 14For every pair of types T and I, where T is a cv-qualified or cv-
2503 unqualified complete object type and I is a promoted integral type,
2504 there exist candidate operator functions of the form
2505 T* operator+(T*, I);
2506 T& operator[](T*, I);
2507 T* operator-(T*, I);
2508 T* operator+(I, T*);
2509 T& operator[](I, T*);
2511 15For every T, where T is a pointer to complete object type, there exist
2512 candidate operator functions of the form112)
2513 ptrdiff_t operator-(T, T);
2515 16For every pointer or enumeration type T, there exist candidate operator
2516 functions of the form
2517 bool operator<(T, T);
2518 bool operator>(T, T);
2519 bool operator<=(T, T);
2520 bool operator>=(T, T);
2521 bool operator==(T, T);
2522 bool operator!=(T, T);
2524 17For every pointer to member type T, there exist candidate operator
2525 functions of the form
2526 bool operator==(T, T);
2527 bool operator!=(T, T); */
2530 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2532 if (TYPE_PTROB_P (type1
)
2533 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2535 type2
= ptrdiff_type_node
;
2539 case TRUNC_DIV_EXPR
:
2540 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2546 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2547 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2549 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2554 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2566 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2568 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2570 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2571 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2573 if (TYPE_PTR_P (type1
)
2574 && null_ptr_cst_p (args
[1]))
2579 if (null_ptr_cst_p (args
[0])
2580 && TYPE_PTR_P (type2
))
2588 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2591 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2593 type1
= ptrdiff_type_node
;
2596 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2598 type2
= ptrdiff_type_node
;
2603 /* 18For every pair of promoted integral types L and R, there exist candi-
2604 date operator functions of the form
2611 where LR is the result of the usual arithmetic conversions between
2614 case TRUNC_MOD_EXPR
:
2620 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2624 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2625 type, VQ is either volatile or empty, and R is a promoted arithmetic
2626 type, there exist candidate operator functions of the form
2627 VQ L& operator=(VQ L&, R);
2628 VQ L& operator*=(VQ L&, R);
2629 VQ L& operator/=(VQ L&, R);
2630 VQ L& operator+=(VQ L&, R);
2631 VQ L& operator-=(VQ L&, R);
2633 20For every pair T, VQ), where T is any type and VQ is either volatile
2634 or empty, there exist candidate operator functions of the form
2635 T*VQ& operator=(T*VQ&, T*);
2637 21For every pair T, VQ), where T is a pointer to member type and VQ is
2638 either volatile or empty, there exist candidate operator functions of
2640 VQ T& operator=(VQ T&, T);
2642 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2643 unqualified complete object type, VQ is either volatile or empty, and
2644 I is a promoted integral type, there exist candidate operator func-
2646 T*VQ& operator+=(T*VQ&, I);
2647 T*VQ& operator-=(T*VQ&, I);
2649 23For every triple L, VQ, R), where L is an integral or enumeration
2650 type, VQ is either volatile or empty, and R is a promoted integral
2651 type, there exist candidate operator functions of the form
2653 VQ L& operator%=(VQ L&, R);
2654 VQ L& operator<<=(VQ L&, R);
2655 VQ L& operator>>=(VQ L&, R);
2656 VQ L& operator&=(VQ L&, R);
2657 VQ L& operator^=(VQ L&, R);
2658 VQ L& operator|=(VQ L&, R); */
2665 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2667 type2
= ptrdiff_type_node
;
2671 case TRUNC_DIV_EXPR
:
2672 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2676 case TRUNC_MOD_EXPR
:
2682 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2687 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2689 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2690 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2691 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2692 || ((TYPE_PTRMEMFUNC_P (type1
)
2693 || TYPE_PTR_P (type1
))
2694 && null_ptr_cst_p (args
[1])))
2704 type1
= build_reference_type (type1
);
2710 For every pair of promoted arithmetic types L and R, there
2711 exist candidate operator functions of the form
2713 LR operator?(bool, L, R);
2715 where LR is the result of the usual arithmetic conversions
2716 between types L and R.
2718 For every type T, where T is a pointer or pointer-to-member
2719 type, there exist candidate operator functions of the form T
2720 operator?(bool, T, T); */
2722 if (promoted_arithmetic_type_p (type1
)
2723 && promoted_arithmetic_type_p (type2
))
2727 /* Otherwise, the types should be pointers. */
2728 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2731 /* We don't check that the two types are the same; the logic
2732 below will actually create two candidates; one in which both
2733 parameter types are TYPE1, and one in which both parameter
2739 if (ARITHMETIC_TYPE_P (type1
))
2747 /* Make sure we don't create builtin candidates with dependent types. */
2748 bool u1
= uses_template_parms (type1
);
2749 bool u2
= type2
? uses_template_parms (type2
) : false;
2752 /* Try to recover if one of the types is non-dependent. But if
2753 there's only one type, there's nothing we can do. */
2756 /* And we lose if both are dependent. */
2759 /* Or if they have different forms. */
2760 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2769 /* If we're dealing with two pointer types or two enumeral types,
2770 we need candidates for both of them. */
2771 if (type2
&& !same_type_p (type1
, type2
)
2772 && TREE_CODE (type1
) == TREE_CODE (type2
)
2773 && (TREE_CODE (type1
) == REFERENCE_TYPE
2774 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2775 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2776 || TYPE_PTRMEMFUNC_P (type1
)
2777 || MAYBE_CLASS_TYPE_P (type1
)
2778 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2780 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2782 tree cptype
= composite_pointer_type (type1
, type2
,
2787 if (cptype
!= error_mark_node
)
2789 build_builtin_candidate
2790 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
2796 build_builtin_candidate
2797 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
2798 build_builtin_candidate
2799 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
2803 build_builtin_candidate
2804 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
2808 type_decays_to (tree type
)
2810 if (TREE_CODE (type
) == ARRAY_TYPE
)
2811 return build_pointer_type (TREE_TYPE (type
));
2812 if (TREE_CODE (type
) == FUNCTION_TYPE
)
2813 return build_pointer_type (type
);
2817 /* There are three conditions of builtin candidates:
2819 1) bool-taking candidates. These are the same regardless of the input.
2820 2) pointer-pair taking candidates. These are generated for each type
2821 one of the input types converts to.
2822 3) arithmetic candidates. According to the standard, we should generate
2823 all of these, but I'm trying not to...
2825 Here we generate a superset of the possible candidates for this particular
2826 case. That is a subset of the full set the standard defines, plus some
2827 other cases which the standard disallows. add_builtin_candidate will
2828 filter out the invalid set. */
2831 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
2832 enum tree_code code2
, tree fnname
, tree
*args
,
2833 int flags
, tsubst_flags_t complain
)
2837 tree type
, argtypes
[3], t
;
2838 /* TYPES[i] is the set of possible builtin-operator parameter types
2839 we will consider for the Ith argument. */
2840 vec
<tree
, va_gc
> *types
[2];
2843 for (i
= 0; i
< 3; ++i
)
2846 argtypes
[i
] = unlowered_expr_type (args
[i
]);
2848 argtypes
[i
] = NULL_TREE
;
2853 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2854 and VQ is either volatile or empty, there exist candidate operator
2855 functions of the form
2856 VQ T& operator++(VQ T&); */
2858 case POSTINCREMENT_EXPR
:
2859 case PREINCREMENT_EXPR
:
2860 case POSTDECREMENT_EXPR
:
2861 case PREDECREMENT_EXPR
:
2866 /* 24There also exist candidate operator functions of the form
2867 bool operator!(bool);
2868 bool operator&&(bool, bool);
2869 bool operator||(bool, bool); */
2871 case TRUTH_NOT_EXPR
:
2872 build_builtin_candidate
2873 (candidates
, fnname
, boolean_type_node
,
2874 NULL_TREE
, args
, argtypes
, flags
, complain
);
2877 case TRUTH_ORIF_EXPR
:
2878 case TRUTH_ANDIF_EXPR
:
2879 build_builtin_candidate
2880 (candidates
, fnname
, boolean_type_node
,
2881 boolean_type_node
, args
, argtypes
, flags
, complain
);
2903 types
[0] = make_tree_vector ();
2904 types
[1] = make_tree_vector ();
2906 for (i
= 0; i
< 2; ++i
)
2910 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
2914 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
2917 convs
= lookup_conversions (argtypes
[i
]);
2919 if (code
== COND_EXPR
)
2921 if (real_lvalue_p (args
[i
]))
2922 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
2924 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
2930 for (; convs
; convs
= TREE_CHAIN (convs
))
2932 type
= TREE_TYPE (convs
);
2935 && (TREE_CODE (type
) != REFERENCE_TYPE
2936 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
2939 if (code
== COND_EXPR
&& TREE_CODE (type
) == REFERENCE_TYPE
)
2940 vec_safe_push (types
[i
], type
);
2942 type
= non_reference (type
);
2943 if (i
!= 0 || ! ref1
)
2945 type
= cv_unqualified (type_decays_to (type
));
2946 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
2947 vec_safe_push (types
[i
], type
);
2948 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
2949 type
= type_promotes_to (type
);
2952 if (! vec_member (type
, types
[i
]))
2953 vec_safe_push (types
[i
], type
);
2958 if (code
== COND_EXPR
&& real_lvalue_p (args
[i
]))
2959 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
2960 type
= non_reference (argtypes
[i
]);
2961 if (i
!= 0 || ! ref1
)
2963 type
= cv_unqualified (type_decays_to (type
));
2964 if (enum_p
&& UNSCOPED_ENUM_P (type
))
2965 vec_safe_push (types
[i
], type
);
2966 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
2967 type
= type_promotes_to (type
);
2969 vec_safe_push (types
[i
], type
);
2973 /* Run through the possible parameter types of both arguments,
2974 creating candidates with those parameter types. */
2975 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
2980 if (!types
[1]->is_empty ())
2981 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
2982 add_builtin_candidate
2983 (candidates
, code
, code2
, fnname
, t
,
2984 u
, args
, argtypes
, flags
, complain
);
2986 add_builtin_candidate
2987 (candidates
, code
, code2
, fnname
, t
,
2988 NULL_TREE
, args
, argtypes
, flags
, complain
);
2991 release_tree_vector (types
[0]);
2992 release_tree_vector (types
[1]);
2996 /* If TMPL can be successfully instantiated as indicated by
2997 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2999 TMPL is the template. EXPLICIT_TARGS are any explicit template
3000 arguments. ARGLIST is the arguments provided at the call-site.
3001 This does not change ARGLIST. The RETURN_TYPE is the desired type
3002 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3003 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3004 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3006 static struct z_candidate
*
3007 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3008 tree ctype
, tree explicit_targs
, tree first_arg
,
3009 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3010 tree access_path
, tree conversion_path
,
3011 int flags
, tree obj
, unification_kind_t strict
,
3012 tsubst_flags_t complain
)
3014 int ntparms
= DECL_NTPARMS (tmpl
);
3015 tree targs
= make_tree_vec (ntparms
);
3016 unsigned int len
= vec_safe_length (arglist
);
3017 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3018 unsigned int skip_without_in_chrg
= 0;
3019 tree first_arg_without_in_chrg
= first_arg
;
3020 tree
*args_without_in_chrg
;
3021 unsigned int nargs_without_in_chrg
;
3022 unsigned int ia
, ix
;
3024 struct z_candidate
*cand
;
3026 struct rejection_reason
*reason
= NULL
;
3029 /* We don't do deduction on the in-charge parameter, the VTT
3030 parameter or 'this'. */
3031 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3033 if (first_arg_without_in_chrg
!= NULL_TREE
)
3034 first_arg_without_in_chrg
= NULL_TREE
;
3036 ++skip_without_in_chrg
;
3039 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3040 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3041 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3043 if (first_arg_without_in_chrg
!= NULL_TREE
)
3044 first_arg_without_in_chrg
= NULL_TREE
;
3046 ++skip_without_in_chrg
;
3049 if (len
< skip_without_in_chrg
)
3052 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3053 + (len
- skip_without_in_chrg
));
3054 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3056 if (first_arg_without_in_chrg
!= NULL_TREE
)
3058 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3061 for (ix
= skip_without_in_chrg
;
3062 vec_safe_iterate (arglist
, ix
, &arg
);
3065 args_without_in_chrg
[ia
] = arg
;
3068 gcc_assert (ia
== nargs_without_in_chrg
);
3070 errs
= errorcount
+sorrycount
;
3071 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3072 args_without_in_chrg
,
3073 nargs_without_in_chrg
,
3074 return_type
, strict
, flags
, false,
3075 complain
& tf_decltype
);
3077 if (fn
== error_mark_node
)
3079 /* Don't repeat unification later if it already resulted in errors. */
3080 if (errorcount
+sorrycount
== errs
)
3081 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3082 targs
, args_without_in_chrg
,
3083 nargs_without_in_chrg
,
3084 return_type
, strict
, flags
);
3086 reason
= template_unification_error_rejection ();
3092 A member function template is never instantiated to perform the
3093 copy of a class object to an object of its class type.
3095 It's a little unclear what this means; the standard explicitly
3096 does allow a template to be used to copy a class. For example,
3101 template <class T> A(const T&);
3104 void g () { A a (f ()); }
3106 the member template will be used to make the copy. The section
3107 quoted above appears in the paragraph that forbids constructors
3108 whose only parameter is (a possibly cv-qualified variant of) the
3109 class type, and a logical interpretation is that the intent was
3110 to forbid the instantiation of member templates which would then
3112 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3114 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3115 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3118 reason
= invalid_copy_with_fn_template_rejection ();
3123 if (obj
!= NULL_TREE
)
3124 /* Aha, this is a conversion function. */
3125 cand
= add_conv_candidate (candidates
, fn
, obj
, first_arg
, arglist
,
3126 access_path
, conversion_path
, complain
);
3128 cand
= add_function_candidate (candidates
, fn
, ctype
,
3129 first_arg
, arglist
, access_path
,
3130 conversion_path
, flags
, complain
);
3131 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3132 /* This situation can occur if a member template of a template
3133 class is specialized. Then, instantiate_template might return
3134 an instantiation of the specialization, in which case the
3135 DECL_TI_TEMPLATE field will point at the original
3136 specialization. For example:
3138 template <class T> struct S { template <class U> void f(U);
3139 template <> void f(int) {}; };
3143 Here, TMPL will be template <class U> S<double>::f(U).
3144 And, instantiate template will give us the specialization
3145 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3146 for this will point at template <class T> template <> S<T>::f(int),
3147 so that we can find the definition. For the purposes of
3148 overload resolution, however, we want the original TMPL. */
3149 cand
->template_decl
= build_template_info (tmpl
, targs
);
3151 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3152 cand
->explicit_targs
= explicit_targs
;
3156 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3157 access_path
, conversion_path
, 0, reason
, flags
);
3161 static struct z_candidate
*
3162 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3163 tree explicit_targs
, tree first_arg
,
3164 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3165 tree access_path
, tree conversion_path
, int flags
,
3166 unification_kind_t strict
, tsubst_flags_t complain
)
3169 add_template_candidate_real (candidates
, tmpl
, ctype
,
3170 explicit_targs
, first_arg
, arglist
,
3171 return_type
, access_path
, conversion_path
,
3172 flags
, NULL_TREE
, strict
, complain
);
3176 static struct z_candidate
*
3177 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3178 tree obj
, tree first_arg
,
3179 const vec
<tree
, va_gc
> *arglist
,
3180 tree return_type
, tree access_path
,
3181 tree conversion_path
, tsubst_flags_t complain
)
3184 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3185 first_arg
, arglist
, return_type
, access_path
,
3186 conversion_path
, 0, obj
, DEDUCE_CONV
,
3190 /* The CANDS are the set of candidates that were considered for
3191 overload resolution. Return the set of viable candidates, or CANDS
3192 if none are viable. If any of the candidates were viable, set
3193 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3194 considered viable only if it is strictly viable. */
3196 static struct z_candidate
*
3197 splice_viable (struct z_candidate
*cands
,
3201 struct z_candidate
*viable
;
3202 struct z_candidate
**last_viable
;
3203 struct z_candidate
**cand
;
3204 bool found_strictly_viable
= false;
3206 /* Be strict inside templates, since build_over_call won't actually
3207 do the conversions to get pedwarns. */
3208 if (processing_template_decl
)
3212 last_viable
= &viable
;
3213 *any_viable_p
= false;
3218 struct z_candidate
*c
= *cand
;
3220 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3222 /* Be strict in the presence of a viable candidate. Also if
3223 there are template candidates, so that we get deduction errors
3224 for them instead of silently preferring a bad conversion. */
3226 if (viable
&& !found_strictly_viable
)
3228 /* Put any spliced near matches back onto the main list so
3229 that we see them if there is no strict match. */
3230 *any_viable_p
= false;
3231 *last_viable
= cands
;
3234 last_viable
= &viable
;
3238 if (strict_p
? c
->viable
== 1 : c
->viable
)
3243 last_viable
= &c
->next
;
3244 *any_viable_p
= true;
3246 found_strictly_viable
= true;
3252 return viable
? viable
: cands
;
3256 any_strictly_viable (struct z_candidate
*cands
)
3258 for (; cands
; cands
= cands
->next
)
3259 if (cands
->viable
== 1)
3264 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3265 words, it is about to become the "this" pointer for a member
3266 function call. Take the address of the object. */
3269 build_this (tree obj
)
3271 /* In a template, we are only concerned about the type of the
3272 expression, so we can take a shortcut. */
3273 if (processing_template_decl
)
3274 return build_address (obj
);
3276 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3279 /* Returns true iff functions are equivalent. Equivalent functions are
3280 not '==' only if one is a function-local extern function or if
3281 both are extern "C". */
3284 equal_functions (tree fn1
, tree fn2
)
3286 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3288 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3290 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3291 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3292 return decls_match (fn1
, fn2
);
3296 /* Print information about a candidate being rejected due to INFO. */
3299 print_conversion_rejection (location_t loc
, struct conversion_info
*info
)
3301 tree from
= info
->from
;
3303 from
= lvalue_type (from
);
3304 if (info
->n_arg
== -1)
3306 /* Conversion of implicit `this' argument failed. */
3307 if (!TYPE_P (info
->from
))
3308 /* A bad conversion for 'this' must be discarding cv-quals. */
3309 inform (loc
, " passing %qT as %<this%> "
3310 "argument discards qualifiers",
3313 inform (loc
, " no known conversion for implicit "
3314 "%<this%> parameter from %qT to %qT",
3315 from
, info
->to_type
);
3317 else if (!TYPE_P (info
->from
))
3319 if (info
->n_arg
>= 0)
3320 inform (loc
, " conversion of argument %d would be ill-formed:",
3322 perform_implicit_conversion (info
->to_type
, info
->from
,
3323 tf_warning_or_error
);
3325 else if (info
->n_arg
== -2)
3326 /* Conversion of conversion function return value failed. */
3327 inform (loc
, " no known conversion from %qT to %qT",
3328 from
, info
->to_type
);
3330 inform (loc
, " no known conversion for argument %d from %qT to %qT",
3331 info
->n_arg
+ 1, from
, info
->to_type
);
3334 /* Print information about a candidate with WANT parameters and we found
3338 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3340 inform_n (loc
, want
,
3341 " candidate expects %d argument, %d provided",
3342 " candidate expects %d arguments, %d provided",
3346 /* Print information about one overload candidate CANDIDATE. MSGSTR
3347 is the text to print before the candidate itself.
3349 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3350 to have been run through gettext by the caller. This wart makes
3351 life simpler in print_z_candidates and for the translators. */
3354 print_z_candidate (location_t loc
, const char *msgstr
,
3355 struct z_candidate
*candidate
)
3357 const char *msg
= (msgstr
== NULL
3359 : ACONCAT ((msgstr
, " ", NULL
)));
3360 location_t cloc
= location_of (candidate
->fn
);
3362 if (identifier_p (candidate
->fn
))
3365 if (candidate
->num_convs
== 3)
3366 inform (cloc
, "%s%D(%T, %T, %T) <built-in>", msg
, candidate
->fn
,
3367 candidate
->convs
[0]->type
,
3368 candidate
->convs
[1]->type
,
3369 candidate
->convs
[2]->type
);
3370 else if (candidate
->num_convs
== 2)
3371 inform (cloc
, "%s%D(%T, %T) <built-in>", msg
, candidate
->fn
,
3372 candidate
->convs
[0]->type
,
3373 candidate
->convs
[1]->type
);
3375 inform (cloc
, "%s%D(%T) <built-in>", msg
, candidate
->fn
,
3376 candidate
->convs
[0]->type
);
3378 else if (TYPE_P (candidate
->fn
))
3379 inform (cloc
, "%s%T <conversion>", msg
, candidate
->fn
);
3380 else if (candidate
->viable
== -1)
3381 inform (cloc
, "%s%#D <near match>", msg
, candidate
->fn
);
3382 else if (DECL_DELETED_FN (candidate
->fn
))
3383 inform (cloc
, "%s%#D <deleted>", msg
, candidate
->fn
);
3385 inform (cloc
, "%s%#D", msg
, candidate
->fn
);
3386 /* Give the user some information about why this candidate failed. */
3387 if (candidate
->reason
!= NULL
)
3389 struct rejection_reason
*r
= candidate
->reason
;
3394 print_arity_information (cloc
, r
->u
.arity
.actual
,
3395 r
->u
.arity
.expected
);
3397 case rr_arg_conversion
:
3398 print_conversion_rejection (cloc
, &r
->u
.conversion
);
3400 case rr_bad_arg_conversion
:
3401 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
);
3403 case rr_explicit_conversion
:
3404 inform (cloc
, " return type %qT of explicit conversion function "
3405 "cannot be converted to %qT with a qualification "
3406 "conversion", r
->u
.conversion
.from
,
3407 r
->u
.conversion
.to_type
);
3409 case rr_template_conversion
:
3410 inform (cloc
, " conversion from return type %qT of template "
3411 "conversion function specialization to %qT is not an "
3412 "exact match", r
->u
.conversion
.from
,
3413 r
->u
.conversion
.to_type
);
3415 case rr_template_unification
:
3416 /* We use template_unification_error_rejection if unification caused
3417 actual non-SFINAE errors, in which case we don't need to repeat
3419 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3421 inform (cloc
, " substitution of deduced template arguments "
3422 "resulted in errors seen above");
3425 /* Re-run template unification with diagnostics. */
3426 inform (cloc
, " template argument deduction/substitution failed:");
3427 fn_type_unification (r
->u
.template_unification
.tmpl
,
3428 r
->u
.template_unification
.explicit_targs
,
3430 (r
->u
.template_unification
.num_targs
)),
3431 r
->u
.template_unification
.args
,
3432 r
->u
.template_unification
.nargs
,
3433 r
->u
.template_unification
.return_type
,
3434 r
->u
.template_unification
.strict
,
3435 r
->u
.template_unification
.flags
,
3438 case rr_invalid_copy
:
3440 " a constructor taking a single argument of its own "
3441 "class type is invalid");
3443 case rr_constraint_failure
:
3445 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3446 tree args
= r
->u
.template_instantiation
.targs
;
3447 diagnose_constraints (cloc
, tmpl
, args
);
3452 /* This candidate didn't have any issues or we failed to
3453 handle a particular code. Either way... */
3460 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3462 struct z_candidate
*cand1
;
3463 struct z_candidate
**cand2
;
3468 /* Remove non-viable deleted candidates. */
3470 for (cand2
= &cand1
; *cand2
; )
3472 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3473 && !(*cand2
)->viable
3474 && DECL_DELETED_FN ((*cand2
)->fn
))
3475 *cand2
= (*cand2
)->next
;
3477 cand2
= &(*cand2
)->next
;
3479 /* ...if there are any non-deleted ones. */
3483 /* There may be duplicates in the set of candidates. We put off
3484 checking this condition as long as possible, since we have no way
3485 to eliminate duplicates from a set of functions in less than n^2
3486 time. Now we are about to emit an error message, so it is more
3487 permissible to go slowly. */
3488 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3490 tree fn
= cand1
->fn
;
3491 /* Skip builtin candidates and conversion functions. */
3494 cand2
= &cand1
->next
;
3497 if (DECL_P ((*cand2
)->fn
)
3498 && equal_functions (fn
, (*cand2
)->fn
))
3499 *cand2
= (*cand2
)->next
;
3501 cand2
= &(*cand2
)->next
;
3505 for (; candidates
; candidates
= candidates
->next
)
3506 print_z_candidate (loc
, "candidate:", candidates
);
3509 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3510 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3511 the result of the conversion function to convert it to the final
3512 desired type. Merge the two sequences into a single sequence,
3513 and return the merged sequence. */
3516 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3519 bool bad
= user_seq
->bad_p
;
3521 gcc_assert (user_seq
->kind
== ck_user
);
3523 /* Find the end of the second conversion sequence. */
3524 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3526 /* The entire sequence is a user-conversion sequence. */
3527 (*t
)->user_conv_p
= true;
3532 /* Replace the identity conversion with the user conversion
3539 /* Handle overload resolution for initializing an object of class type from
3540 an initializer list. First we look for a suitable constructor that
3541 takes a std::initializer_list; if we don't find one, we then look for a
3542 non-list constructor.
3544 Parameters are as for add_candidates, except that the arguments are in
3545 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3546 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3549 add_list_candidates (tree fns
, tree first_arg
,
3550 tree init_list
, tree totype
,
3551 tree explicit_targs
, bool template_only
,
3552 tree conversion_path
, tree access_path
,
3554 struct z_candidate
**candidates
,
3555 tsubst_flags_t complain
)
3557 vec
<tree
, va_gc
> *args
;
3559 gcc_assert (*candidates
== NULL
);
3561 /* We're looking for a ctor for list-initialization. */
3562 flags
|= LOOKUP_LIST_INIT_CTOR
;
3563 /* And we don't allow narrowing conversions. We also use this flag to
3564 avoid the copy constructor call for copy-list-initialization. */
3565 flags
|= LOOKUP_NO_NARROWING
;
3567 /* Always use the default constructor if the list is empty (DR 990). */
3568 if (CONSTRUCTOR_NELTS (init_list
) == 0
3569 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3571 /* If the class has a list ctor, try passing the list as a single
3572 argument first, but only consider list ctors. */
3573 else if (TYPE_HAS_LIST_CTOR (totype
))
3575 flags
|= LOOKUP_LIST_ONLY
;
3576 args
= make_tree_vector_single (init_list
);
3577 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3578 explicit_targs
, template_only
, conversion_path
,
3579 access_path
, flags
, candidates
, complain
);
3580 if (any_strictly_viable (*candidates
))
3584 args
= ctor_to_vec (init_list
);
3586 /* We aren't looking for list-ctors anymore. */
3587 flags
&= ~LOOKUP_LIST_ONLY
;
3588 /* We allow more user-defined conversions within an init-list. */
3589 flags
&= ~LOOKUP_NO_CONVERSION
;
3591 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3592 explicit_targs
, template_only
, conversion_path
,
3593 access_path
, flags
, candidates
, complain
);
3596 /* Returns the best overload candidate to perform the requested
3597 conversion. This function is used for three the overloading situations
3598 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3599 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3600 per [dcl.init.ref], so we ignore temporary bindings. */
3602 static struct z_candidate
*
3603 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3604 tsubst_flags_t complain
)
3606 struct z_candidate
*candidates
, *cand
;
3608 tree ctors
= NULL_TREE
;
3609 tree conv_fns
= NULL_TREE
;
3610 conversion
*conv
= NULL
;
3611 tree first_arg
= NULL_TREE
;
3612 vec
<tree
, va_gc
> *args
= NULL
;
3619 fromtype
= TREE_TYPE (expr
);
3621 /* We represent conversion within a hierarchy using RVALUE_CONV and
3622 BASE_CONV, as specified by [over.best.ics]; these become plain
3623 constructor calls, as specified in [dcl.init]. */
3624 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3625 || !DERIVED_FROM_P (totype
, fromtype
));
3627 if (MAYBE_CLASS_TYPE_P (totype
))
3628 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3629 creating a garbage BASELINK; constructors can't be inherited. */
3630 ctors
= lookup_fnfields_slot (totype
, complete_ctor_identifier
);
3632 if (MAYBE_CLASS_TYPE_P (fromtype
))
3634 tree to_nonref
= non_reference (totype
);
3635 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3636 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3637 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3639 /* [class.conv.fct] A conversion function is never used to
3640 convert a (possibly cv-qualified) object to the (possibly
3641 cv-qualified) same object type (or a reference to it), to a
3642 (possibly cv-qualified) base class of that type (or a
3643 reference to it)... */
3646 conv_fns
= lookup_conversions (fromtype
);
3650 flags
|= LOOKUP_NO_CONVERSION
;
3651 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3652 flags
|= LOOKUP_NO_NARROWING
;
3654 /* It's OK to bind a temporary for converting constructor arguments, but
3655 not in converting the return value of a conversion operator. */
3656 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3657 | (flags
& LOOKUP_NO_NARROWING
));
3658 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3662 int ctorflags
= flags
;
3664 first_arg
= build_dummy_object (totype
);
3666 /* We should never try to call the abstract or base constructor
3668 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors
))
3669 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors
)));
3671 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3673 /* List-initialization. */
3674 add_list_candidates (ctors
, first_arg
, expr
, totype
, NULL_TREE
,
3675 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3676 ctorflags
, &candidates
, complain
);
3680 args
= make_tree_vector_single (expr
);
3681 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3682 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3683 ctorflags
, &candidates
, complain
);
3686 for (cand
= candidates
; cand
; cand
= cand
->next
)
3688 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3690 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3691 set, then this is copy-initialization. In that case, "The
3692 result of the call is then used to direct-initialize the
3693 object that is the destination of the copy-initialization."
3696 We represent this in the conversion sequence with an
3697 rvalue conversion, which means a constructor call. */
3698 if (TREE_CODE (totype
) != REFERENCE_TYPE
3699 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3701 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3708 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3710 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3711 struct z_candidate
*old_candidates
;
3713 /* If we are called to convert to a reference type, we are trying to
3714 find a direct binding, so don't even consider temporaries. If
3715 we don't find a direct binding, the caller will try again to
3716 look for a temporary binding. */
3717 if (TREE_CODE (totype
) == REFERENCE_TYPE
)
3718 convflags
|= LOOKUP_NO_TEMP_BIND
;
3720 old_candidates
= candidates
;
3721 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3723 conversion_path
, TYPE_BINFO (fromtype
),
3724 flags
, &candidates
, complain
);
3726 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
3728 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
3730 = implicit_conversion (totype
,
3733 /*c_cast_p=*/false, convflags
,
3736 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3737 copy-initialization. In that case, "The result of the
3738 call is then used to direct-initialize the object that is
3739 the destination of the copy-initialization." [dcl.init]
3741 We represent this in the conversion sequence with an
3742 rvalue conversion, which means a constructor call. But
3743 don't add a second rvalue conversion if there's already
3744 one there. Which there really shouldn't be, but it's
3745 harmless since we'd add it here anyway. */
3746 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
3747 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3748 ics
= build_conv (ck_rvalue
, totype
, ics
);
3750 cand
->second_conv
= ics
;
3755 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
3758 else if (DECL_NONCONVERTING_P (cand
->fn
)
3759 && ics
->rank
> cr_exact
)
3761 /* 13.3.1.5: For direct-initialization, those explicit
3762 conversion functions that are not hidden within S and
3763 yield type T or a type that can be converted to type T
3764 with a qualification conversion (4.4) are also candidate
3766 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3767 I've raised this issue with the committee. --jason 9/2011 */
3769 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
3771 else if (cand
->viable
== 1 && ics
->bad_p
)
3775 = bad_arg_conversion_rejection (NULL_TREE
, -2,
3778 else if (primary_template_instantiation_p (cand
->fn
)
3779 && ics
->rank
> cr_exact
)
3781 /* 13.3.3.1.2: If the user-defined conversion is specified by
3782 a specialization of a conversion function template, the
3783 second standard conversion sequence shall have exact match
3786 cand
->reason
= template_conversion_rejection (rettype
, totype
);
3791 candidates
= splice_viable (candidates
, false, &any_viable_p
);
3795 release_tree_vector (args
);
3799 cand
= tourney (candidates
, complain
);
3802 if (complain
& tf_error
)
3804 error ("conversion from %qT to %qT is ambiguous",
3806 print_z_candidates (location_of (expr
), candidates
);
3809 cand
= candidates
; /* any one will do */
3810 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
3811 cand
->second_conv
->user_conv_p
= true;
3812 if (!any_strictly_viable (candidates
))
3813 cand
->second_conv
->bad_p
= true;
3814 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3815 ambiguous conversion is no worse than another user-defined
3822 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
3823 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
3824 else if (cand
->second_conv
->kind
== ck_rvalue
)
3825 /* DR 5: [in the first step of copy-initialization]...if the function
3826 is a constructor, the call initializes a temporary of the
3827 cv-unqualified version of the destination type. */
3828 convtype
= cv_unqualified (totype
);
3831 /* Build the user conversion sequence. */
3835 build_identity_conv (TREE_TYPE (expr
), expr
));
3837 if (cand
->viable
== -1)
3840 /* Remember that this was a list-initialization. */
3841 if (flags
& LOOKUP_NO_NARROWING
)
3842 conv
->check_narrowing
= true;
3844 /* Combine it with the second conversion sequence. */
3845 cand
->second_conv
= merge_conversion_sequences (conv
,
3851 /* Wrapper for above. */
3854 build_user_type_conversion (tree totype
, tree expr
, int flags
,
3855 tsubst_flags_t complain
)
3857 struct z_candidate
*cand
;
3860 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
3861 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
3865 if (cand
->second_conv
->kind
== ck_ambig
)
3866 ret
= error_mark_node
;
3869 expr
= convert_like (cand
->second_conv
, expr
, complain
);
3870 ret
= convert_from_reference (expr
);
3876 timevar_cond_stop (TV_OVERLOAD
, subtime
);
3880 /* Subroutine of convert_nontype_argument.
3882 EXPR is an argument for a template non-type parameter of integral or
3883 enumeration type. Do any necessary conversions (that are permitted for
3884 non-type arguments) to convert it to the parameter type.
3886 If conversion is successful, returns the converted expression;
3887 otherwise, returns error_mark_node. */
3890 build_integral_nontype_arg_conv (tree type
, tree expr
, tsubst_flags_t complain
)
3895 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
3897 if (error_operand_p (expr
))
3898 return error_mark_node
;
3900 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type
));
3902 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3903 p
= conversion_obstack_alloc (0);
3905 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
3907 LOOKUP_IMPLICIT
, complain
);
3909 /* for a non-type template-parameter of integral or
3910 enumeration type, integral promotions (4.5) and integral
3911 conversions (4.7) are applied. */
3912 /* It should be sufficient to check the outermost conversion step, since
3913 there are no qualification conversions to integer type. */
3917 /* A conversion function is OK. If it isn't constexpr, we'll
3918 complain later that the argument isn't constant. */
3920 /* The lvalue-to-rvalue conversion is OK. */
3926 t
= next_conversion (conv
)->type
;
3927 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
))
3930 if (complain
& tf_error
)
3931 error_at (loc
, "conversion from %qT to %qT not considered for "
3932 "non-type template argument", t
, type
);
3933 /* and fall through. */
3941 expr
= convert_like (conv
, expr
, complain
);
3943 expr
= error_mark_node
;
3945 /* Free all the conversions we allocated. */
3946 obstack_free (&conversion_obstack
, p
);
3951 /* Do any initial processing on the arguments to a function call. */
3953 static vec
<tree
, va_gc
> *
3954 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
3959 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
3961 if (error_operand_p (arg
))
3963 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
3965 if (complain
& tf_error
)
3966 error ("invalid use of void expression");
3969 else if (invalid_nonstatic_memfn_p (input_location
, arg
, complain
))
3975 /* Perform overload resolution on FN, which is called with the ARGS.
3977 Return the candidate function selected by overload resolution, or
3978 NULL if the event that overload resolution failed. In the case
3979 that overload resolution fails, *CANDIDATES will be the set of
3980 candidates considered, and ANY_VIABLE_P will be set to true or
3981 false to indicate whether or not any of the candidates were
3984 The ARGS should already have gone through RESOLVE_ARGS before this
3985 function is called. */
3987 static struct z_candidate
*
3988 perform_overload_resolution (tree fn
,
3989 const vec
<tree
, va_gc
> *args
,
3990 struct z_candidate
**candidates
,
3991 bool *any_viable_p
, tsubst_flags_t complain
)
3993 struct z_candidate
*cand
;
3994 tree explicit_targs
;
3997 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
3999 explicit_targs
= NULL_TREE
;
4003 *any_viable_p
= true;
4006 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4007 || TREE_CODE (fn
) == TEMPLATE_DECL
4008 || TREE_CODE (fn
) == OVERLOAD
4009 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4011 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4013 explicit_targs
= TREE_OPERAND (fn
, 1);
4014 fn
= TREE_OPERAND (fn
, 0);
4018 /* Add the various candidate functions. */
4019 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4020 explicit_targs
, template_only
,
4021 /*conversion_path=*/NULL_TREE
,
4022 /*access_path=*/NULL_TREE
,
4024 candidates
, complain
);
4026 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4028 cand
= tourney (*candidates
, complain
);
4032 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4036 /* Print an error message about being unable to build a call to FN with
4037 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4038 be located; CANDIDATES is a possibly empty list of such
4042 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4043 struct z_candidate
*candidates
)
4045 tree name
= DECL_NAME (OVL_CURRENT (fn
));
4046 location_t loc
= location_of (name
);
4048 if (!any_strictly_viable (candidates
))
4049 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4050 name
, build_tree_list_vec (args
));
4052 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4053 name
, build_tree_list_vec (args
));
4055 print_z_candidates (loc
, candidates
);
4058 /* Return an expression for a call to FN (a namespace-scope function,
4059 or a static member function) with the ARGS. This may change
4063 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
, bool koenig_p
,
4064 tsubst_flags_t complain
)
4066 struct z_candidate
*candidates
, *cand
;
4071 if (args
!= NULL
&& *args
!= NULL
)
4073 *args
= resolve_args (*args
, complain
);
4075 return error_mark_node
;
4079 tm_malloc_replacement (fn
);
4081 /* If this function was found without using argument dependent
4082 lookup, then we want to ignore any undeclared friend
4088 fn
= remove_hidden_names (fn
);
4091 if (complain
& tf_error
)
4092 print_error_for_call_failure (orig_fn
, *args
, NULL
);
4093 return error_mark_node
;
4097 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4098 p
= conversion_obstack_alloc (0);
4100 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4105 if (complain
& tf_error
)
4107 // If there is a single (non-viable) function candidate,
4108 // let the error be diagnosed by cp_build_function_call_vec.
4109 if (!any_viable_p
&& candidates
&& ! candidates
->next
4110 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4111 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4113 // Otherwise, emit notes for non-viable candidates.
4114 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4115 fn
= TREE_OPERAND (fn
, 0);
4116 print_error_for_call_failure (fn
, *args
, candidates
);
4118 result
= error_mark_node
;
4122 int flags
= LOOKUP_NORMAL
;
4123 /* If fn is template_id_expr, the call has explicit template arguments
4124 (e.g. func<int>(5)), communicate this info to build_over_call
4125 through flags so that later we can use it to decide whether to warn
4126 about peculiar null pointer conversion. */
4127 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4129 /* If overload resolution selects a specialization of a
4130 function concept for non-dependent template arguments,
4131 the expression is true if the constraints are satisfied
4132 and false otherwise.
4134 NOTE: This is an extension of Concepts Lite TS that
4135 allows constraints to be used in expressions. */
4136 if (flag_concepts
&& !processing_template_decl
)
4138 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4139 tree targs
= DECL_TI_ARGS (cand
->fn
);
4140 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4141 if (DECL_DECLARED_CONCEPT_P (decl
))
4142 return evaluate_function_concept (decl
, targs
);
4145 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4148 result
= build_over_call (cand
, flags
, complain
);
4151 /* Free all the conversions we allocated. */
4152 obstack_free (&conversion_obstack
, p
);
4157 /* Build a call to a global operator new. FNNAME is the name of the
4158 operator (either "operator new" or "operator new[]") and ARGS are
4159 the arguments provided. This may change ARGS. *SIZE points to the
4160 total number of bytes required by the allocation, and is updated if
4161 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4162 be used. If this function determines that no cookie should be
4163 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4164 is not NULL_TREE, it is evaluated before calculating the final
4165 array size, and if it fails, the array size is replaced with
4166 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4167 is non-NULL, it will be set, upon return, to the allocation
4171 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4172 tree
*size
, tree
*cookie_size
, tree size_check
,
4173 tree
*fn
, tsubst_flags_t complain
)
4175 tree original_size
= *size
;
4177 struct z_candidate
*candidates
;
4178 struct z_candidate
*cand
;
4183 /* Set to (size_t)-1 if the size check fails. */
4184 if (size_check
!= NULL_TREE
)
4186 tree errval
= TYPE_MAX_VALUE (sizetype
);
4187 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4188 errval
= throw_bad_array_new_length ();
4189 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4190 original_size
, errval
);
4192 vec_safe_insert (*args
, 0, *size
);
4193 *args
= resolve_args (*args
, complain
);
4195 return error_mark_node
;
4201 If this lookup fails to find the name, or if the allocated type
4202 is not a class type, the allocation function's name is looked
4203 up in the global scope.
4205 we disregard block-scope declarations of "operator new". */
4206 fns
= lookup_function_nonclass (fnname
, *args
, /*block_p=*/false);
4208 /* Figure out what function is being called. */
4209 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4212 /* If no suitable function could be found, issue an error message
4216 if (complain
& tf_error
)
4217 print_error_for_call_failure (fns
, *args
, candidates
);
4218 return error_mark_node
;
4221 /* If a cookie is required, add some extra space. Whether
4222 or not a cookie is required cannot be determined until
4223 after we know which function was called. */
4226 bool use_cookie
= true;
4229 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4230 /* Skip the size_t parameter. */
4231 arg_types
= TREE_CHAIN (arg_types
);
4232 /* Check the remaining parameters (if any). */
4234 && TREE_CHAIN (arg_types
) == void_list_node
4235 && same_type_p (TREE_VALUE (arg_types
),
4238 /* If we need a cookie, adjust the number of bytes allocated. */
4241 /* Update the total size. */
4242 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4243 /* Set to (size_t)-1 if the size check fails. */
4244 gcc_assert (size_check
!= NULL_TREE
);
4245 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4246 *size
, TYPE_MAX_VALUE (sizetype
));
4247 /* Update the argument list to reflect the adjusted size. */
4248 (**args
)[0] = *size
;
4251 *cookie_size
= NULL_TREE
;
4254 /* Tell our caller which function we decided to call. */
4258 /* Build the CALL_EXPR. */
4259 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4262 /* Build a new call to operator(). This may change ARGS. */
4265 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4267 struct z_candidate
*candidates
= 0, *cand
;
4268 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4269 tree type
= TREE_TYPE (obj
);
4271 tree result
= NULL_TREE
;
4274 if (error_operand_p (obj
))
4275 return error_mark_node
;
4277 obj
= prep_operand (obj
);
4279 if (TYPE_PTRMEMFUNC_P (type
))
4281 if (complain
& tf_error
)
4282 /* It's no good looking for an overloaded operator() on a
4283 pointer-to-member-function. */
4284 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj
);
4285 return error_mark_node
;
4288 if (TYPE_BINFO (type
))
4290 fns
= lookup_fnfields (TYPE_BINFO (type
), ansi_opname (CALL_EXPR
), 1);
4291 if (fns
== error_mark_node
)
4292 return error_mark_node
;
4297 if (args
!= NULL
&& *args
!= NULL
)
4299 *args
= resolve_args (*args
, complain
);
4301 return error_mark_node
;
4304 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4305 p
= conversion_obstack_alloc (0);
4309 first_mem_arg
= obj
;
4311 add_candidates (BASELINK_FUNCTIONS (fns
),
4312 first_mem_arg
, *args
, NULL_TREE
,
4314 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4315 LOOKUP_NORMAL
, &candidates
, complain
);
4318 convs
= lookup_conversions (type
);
4320 for (; convs
; convs
= TREE_CHAIN (convs
))
4322 tree fns
= TREE_VALUE (convs
);
4323 tree totype
= TREE_TYPE (convs
);
4325 if (TYPE_PTRFN_P (totype
)
4326 || TYPE_REFFN_P (totype
)
4327 || (TREE_CODE (totype
) == REFERENCE_TYPE
4328 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4329 for (; fns
; fns
= OVL_NEXT (fns
))
4331 tree fn
= OVL_CURRENT (fns
);
4333 if (DECL_NONCONVERTING_P (fn
))
4336 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4337 add_template_conv_candidate
4338 (&candidates
, fn
, obj
, NULL_TREE
, *args
, totype
,
4339 /*access_path=*/NULL_TREE
,
4340 /*conversion_path=*/NULL_TREE
, complain
);
4342 add_conv_candidate (&candidates
, fn
, obj
, NULL_TREE
,
4343 *args
, /*conversion_path=*/NULL_TREE
,
4344 /*access_path=*/NULL_TREE
, complain
);
4348 /* Be strict here because if we choose a bad conversion candidate, the
4349 errors we get won't mention the call context. */
4350 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4353 if (complain
& tf_error
)
4355 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4356 build_tree_list_vec (*args
));
4357 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4359 result
= error_mark_node
;
4363 cand
= tourney (candidates
, complain
);
4366 if (complain
& tf_error
)
4368 error ("call of %<(%T) (%A)%> is ambiguous",
4369 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4370 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4372 result
= error_mark_node
;
4374 /* Since cand->fn will be a type, not a function, for a conversion
4375 function, we must be careful not to unconditionally look at
4377 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4378 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
) == CALL_EXPR
)
4379 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4382 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
, -1,
4384 obj
= convert_from_reference (obj
);
4385 result
= cp_build_function_call_vec (obj
, args
, complain
);
4389 /* Free all the conversions we allocated. */
4390 obstack_free (&conversion_obstack
, p
);
4395 /* Wrapper for above. */
4398 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4401 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4402 ret
= build_op_call_1 (obj
, args
, complain
);
4403 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4407 /* Called by op_error to prepare format strings suitable for the error
4408 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4409 and a suffix (controlled by NTYPES). */
4412 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4416 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4417 : G_("no match for "), errmsg
, NULL
);
4420 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4421 else if (ntypes
== 2)
4422 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4424 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4430 op_error (location_t loc
, enum tree_code code
, enum tree_code code2
,
4431 tree arg1
, tree arg2
, tree arg3
, bool match
)
4435 if (code
== MODIFY_EXPR
)
4436 opname
= assignment_operator_name_info
[code2
].name
;
4438 opname
= operator_name_info
[code
].name
;
4443 if (flag_diagnostics_show_caret
)
4444 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4446 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4448 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4449 "in %<%E ? %E : %E%>"), 3, match
),
4451 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4454 case POSTINCREMENT_EXPR
:
4455 case POSTDECREMENT_EXPR
:
4456 if (flag_diagnostics_show_caret
)
4457 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4458 opname
, TREE_TYPE (arg1
));
4460 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4462 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4466 if (flag_diagnostics_show_caret
)
4467 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4468 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4470 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4472 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4477 if (flag_diagnostics_show_caret
)
4478 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4479 opname
, TREE_TYPE (arg1
));
4481 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4482 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4487 if (flag_diagnostics_show_caret
)
4488 error_at (loc
, op_error_string (G_("%<operator%s%>"), 2, match
),
4489 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4491 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4493 opname
, arg1
, opname
, arg2
,
4494 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4496 if (flag_diagnostics_show_caret
)
4497 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4498 opname
, TREE_TYPE (arg1
));
4500 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4502 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4507 /* Return the implicit conversion sequence that could be used to
4508 convert E1 to E2 in [expr.cond]. */
4511 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4513 tree t1
= non_reference (TREE_TYPE (e1
));
4514 tree t2
= non_reference (TREE_TYPE (e2
));
4520 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4521 implicitly converted (clause _conv_) to the type "lvalue reference to
4522 T2", subject to the constraint that in the conversion the
4523 reference must bind directly (_dcl.init.ref_) to an lvalue.
4525 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4526 implicitly converted to the type "rvalue reference to T2", subject to
4527 the constraint that the reference must bind directly. */
4528 if (lvalue_or_rvalue_with_address_p (e2
))
4530 tree rtype
= cp_build_reference_type (t2
, !real_lvalue_p (e2
));
4531 conv
= implicit_conversion (rtype
,
4535 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4536 |LOOKUP_ONLYCONVERTING
,
4538 if (conv
&& !conv
->bad_p
)
4542 /* If E2 is a prvalue or if neither of the conversions above can be done
4543 and at least one of the operands has (possibly cv-qualified) class
4545 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4550 If E1 and E2 have class type, and the underlying class types are
4551 the same or one is a base class of the other: E1 can be converted
4552 to match E2 if the class of T2 is the same type as, or a base
4553 class of, the class of T1, and the cv-qualification of T2 is the
4554 same cv-qualification as, or a greater cv-qualification than, the
4555 cv-qualification of T1. If the conversion is applied, E1 is
4556 changed to an rvalue of type T2 that still refers to the original
4557 source class object (or the appropriate subobject thereof). */
4558 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4559 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4561 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4563 conv
= build_identity_conv (t1
, e1
);
4564 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4565 TYPE_MAIN_VARIANT (t2
)))
4566 conv
= build_conv (ck_base
, t2
, conv
);
4568 conv
= build_conv (ck_rvalue
, t2
, conv
);
4577 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4578 converted to the type that expression E2 would have if E2 were
4579 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4580 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4581 LOOKUP_IMPLICIT
, complain
);
4584 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4585 arguments to the conditional expression. */
4588 build_conditional_expr_1 (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
4589 tsubst_flags_t complain
)
4593 tree result
= NULL_TREE
;
4594 tree result_type
= NULL_TREE
;
4595 bool lvalue_p
= true;
4596 struct z_candidate
*candidates
= 0;
4597 struct z_candidate
*cand
;
4599 tree orig_arg2
, orig_arg3
;
4601 /* As a G++ extension, the second argument to the conditional can be
4602 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4603 c'.) If the second operand is omitted, make sure it is
4604 calculated only once. */
4607 if (complain
& tf_error
)
4608 pedwarn (loc
, OPT_Wpedantic
,
4609 "ISO C++ forbids omitting the middle term of a ?: expression");
4611 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4612 if (real_lvalue_p (arg1
))
4613 arg2
= arg1
= stabilize_reference (arg1
);
4615 arg2
= arg1
= save_expr (arg1
);
4618 /* If something has already gone wrong, just pass that fact up the
4620 if (error_operand_p (arg1
)
4621 || error_operand_p (arg2
)
4622 || error_operand_p (arg3
))
4623 return error_mark_node
;
4628 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
4630 arg1
= force_rvalue (arg1
, complain
);
4631 arg2
= force_rvalue (arg2
, complain
);
4632 arg3
= force_rvalue (arg3
, complain
);
4634 /* force_rvalue can return error_mark on valid arguments. */
4635 if (error_operand_p (arg1
)
4636 || error_operand_p (arg2
)
4637 || error_operand_p (arg3
))
4638 return error_mark_node
;
4640 tree arg1_type
= TREE_TYPE (arg1
);
4641 arg2_type
= TREE_TYPE (arg2
);
4642 arg3_type
= TREE_TYPE (arg3
);
4644 if (!VECTOR_TYPE_P (arg2_type
)
4645 && !VECTOR_TYPE_P (arg3_type
))
4647 /* Rely on the error messages of the scalar version. */
4648 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
4649 orig_arg2
, orig_arg3
, complain
);
4650 if (scal
== error_mark_node
)
4651 return error_mark_node
;
4652 tree stype
= TREE_TYPE (scal
);
4653 tree ctype
= TREE_TYPE (arg1_type
);
4654 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
4655 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
4657 if (complain
& tf_error
)
4658 error_at (loc
, "inferred scalar type %qT is not an integer or "
4659 "floating point type of the same size as %qT", stype
,
4660 COMPARISON_CLASS_P (arg1
)
4661 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
4663 return error_mark_node
;
4666 tree vtype
= build_opaque_vector_type (stype
,
4667 TYPE_VECTOR_SUBPARTS (arg1_type
));
4668 /* We could pass complain & tf_warning to unsafe_conversion_p,
4669 but the warnings (like Wsign-conversion) have already been
4670 given by the scalar build_conditional_expr_1. We still check
4671 unsafe_conversion_p to forbid truncating long long -> float. */
4672 if (unsafe_conversion_p (loc
, stype
, arg2
, false))
4674 if (complain
& tf_error
)
4675 error_at (loc
, "conversion of scalar %qT to vector %qT "
4676 "involves truncation", arg2_type
, vtype
);
4677 return error_mark_node
;
4679 if (unsafe_conversion_p (loc
, stype
, arg3
, false))
4681 if (complain
& tf_error
)
4682 error_at (loc
, "conversion of scalar %qT to vector %qT "
4683 "involves truncation", arg3_type
, vtype
);
4684 return error_mark_node
;
4687 arg2
= cp_convert (stype
, arg2
, complain
);
4688 arg2
= save_expr (arg2
);
4689 arg2
= build_vector_from_val (vtype
, arg2
);
4691 arg3
= cp_convert (stype
, arg3
, complain
);
4692 arg3
= save_expr (arg3
);
4693 arg3
= build_vector_from_val (vtype
, arg3
);
4697 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
4699 enum stv_conv convert_flag
=
4700 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
4701 complain
& tf_error
);
4703 switch (convert_flag
)
4706 return error_mark_node
;
4709 arg2
= save_expr (arg2
);
4710 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
4711 arg2
= build_vector_from_val (arg3_type
, arg2
);
4712 arg2_type
= TREE_TYPE (arg2
);
4717 arg3
= save_expr (arg3
);
4718 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
4719 arg3
= build_vector_from_val (arg2_type
, arg3
);
4720 arg3_type
= TREE_TYPE (arg3
);
4728 if (!same_type_p (arg2_type
, arg3_type
)
4729 || TYPE_VECTOR_SUBPARTS (arg1_type
)
4730 != TYPE_VECTOR_SUBPARTS (arg2_type
)
4731 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
4733 if (complain
& tf_error
)
4735 "incompatible vector types in conditional expression: "
4736 "%qT, %qT and %qT", TREE_TYPE (arg1
),
4737 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
4738 return error_mark_node
;
4741 if (!COMPARISON_CLASS_P (arg1
))
4742 arg1
= cp_build_binary_op (loc
, NE_EXPR
, arg1
,
4743 build_zero_cst (arg1_type
), complain
);
4744 return fold_build3 (VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
4749 The first expression is implicitly converted to bool (clause
4751 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
4753 if (error_operand_p (arg1
))
4754 return error_mark_node
;
4758 If either the second or the third operand has type (possibly
4759 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4760 array-to-pointer (_conv.array_), and function-to-pointer
4761 (_conv.func_) standard conversions are performed on the second
4762 and third operands. */
4763 arg2_type
= unlowered_expr_type (arg2
);
4764 arg3_type
= unlowered_expr_type (arg3
);
4765 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
4767 /* Do the conversions. We don't these for `void' type arguments
4768 since it can't have any effect and since decay_conversion
4769 does not handle that case gracefully. */
4770 if (!VOID_TYPE_P (arg2_type
))
4771 arg2
= decay_conversion (arg2
, complain
);
4772 if (!VOID_TYPE_P (arg3_type
))
4773 arg3
= decay_conversion (arg3
, complain
);
4774 arg2_type
= TREE_TYPE (arg2
);
4775 arg3_type
= TREE_TYPE (arg3
);
4779 One of the following shall hold:
4781 --The second or the third operand (but not both) is a
4782 throw-expression (_except.throw_); the result is of the
4783 type of the other and is an rvalue.
4785 --Both the second and the third operands have type void; the
4786 result is of type void and is an rvalue.
4788 We must avoid calling force_rvalue for expressions of type
4789 "void" because it will complain that their value is being
4791 if (TREE_CODE (arg2
) == THROW_EXPR
4792 && TREE_CODE (arg3
) != THROW_EXPR
)
4794 if (!VOID_TYPE_P (arg3_type
))
4796 arg3
= force_rvalue (arg3
, complain
);
4797 if (arg3
== error_mark_node
)
4798 return error_mark_node
;
4800 arg3_type
= TREE_TYPE (arg3
);
4801 result_type
= arg3_type
;
4803 else if (TREE_CODE (arg2
) != THROW_EXPR
4804 && TREE_CODE (arg3
) == THROW_EXPR
)
4806 if (!VOID_TYPE_P (arg2_type
))
4808 arg2
= force_rvalue (arg2
, complain
);
4809 if (arg2
== error_mark_node
)
4810 return error_mark_node
;
4812 arg2_type
= TREE_TYPE (arg2
);
4813 result_type
= arg2_type
;
4815 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
4816 result_type
= void_type_node
;
4819 if (complain
& tf_error
)
4821 if (VOID_TYPE_P (arg2_type
))
4822 error_at (EXPR_LOC_OR_LOC (arg3
, loc
),
4823 "second operand to the conditional operator "
4824 "is of type %<void%>, but the third operand is "
4825 "neither a throw-expression nor of type %<void%>");
4827 error_at (EXPR_LOC_OR_LOC (arg2
, loc
),
4828 "third operand to the conditional operator "
4829 "is of type %<void%>, but the second operand is "
4830 "neither a throw-expression nor of type %<void%>");
4832 return error_mark_node
;
4836 goto valid_operands
;
4840 Otherwise, if the second and third operand have different types,
4841 and either has (possibly cv-qualified) class type, or if both are
4842 glvalues of the same value category and the same type except for
4843 cv-qualification, an attempt is made to convert each of those operands
4844 to the type of the other. */
4845 else if (!same_type_p (arg2_type
, arg3_type
)
4846 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
4847 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
4849 && lvalue_or_rvalue_with_address_p (arg2
)
4850 && lvalue_or_rvalue_with_address_p (arg3
)
4851 && real_lvalue_p (arg2
) == real_lvalue_p (arg3
))))
4855 bool converted
= false;
4857 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4858 p
= conversion_obstack_alloc (0);
4860 conv2
= conditional_conversion (arg2
, arg3
, complain
);
4861 conv3
= conditional_conversion (arg3
, arg2
, complain
);
4865 If both can be converted, or one can be converted but the
4866 conversion is ambiguous, the program is ill-formed. If
4867 neither can be converted, the operands are left unchanged and
4868 further checking is performed as described below. If exactly
4869 one conversion is possible, that conversion is applied to the
4870 chosen operand and the converted operand is used in place of
4871 the original operand for the remainder of this section. */
4872 if ((conv2
&& !conv2
->bad_p
4873 && conv3
&& !conv3
->bad_p
)
4874 || (conv2
&& conv2
->kind
== ck_ambig
)
4875 || (conv3
&& conv3
->kind
== ck_ambig
))
4877 if (complain
& tf_error
)
4879 error_at (loc
, "operands to ?: have different types %qT and %qT",
4880 arg2_type
, arg3_type
);
4881 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
4882 inform (loc
, " and each type can be converted to the other");
4883 else if (conv2
&& conv2
->kind
== ck_ambig
)
4884 convert_like (conv2
, arg2
, complain
);
4886 convert_like (conv3
, arg3
, complain
);
4888 result
= error_mark_node
;
4890 else if (conv2
&& !conv2
->bad_p
)
4892 arg2
= convert_like (conv2
, arg2
, complain
);
4893 arg2
= convert_from_reference (arg2
);
4894 arg2_type
= TREE_TYPE (arg2
);
4895 /* Even if CONV2 is a valid conversion, the result of the
4896 conversion may be invalid. For example, if ARG3 has type
4897 "volatile X", and X does not have a copy constructor
4898 accepting a "volatile X&", then even if ARG2 can be
4899 converted to X, the conversion will fail. */
4900 if (error_operand_p (arg2
))
4901 result
= error_mark_node
;
4904 else if (conv3
&& !conv3
->bad_p
)
4906 arg3
= convert_like (conv3
, arg3
, complain
);
4907 arg3
= convert_from_reference (arg3
);
4908 arg3_type
= TREE_TYPE (arg3
);
4909 if (error_operand_p (arg3
))
4910 result
= error_mark_node
;
4914 /* Free all the conversions we allocated. */
4915 obstack_free (&conversion_obstack
, p
);
4920 /* If, after the conversion, both operands have class type,
4921 treat the cv-qualification of both operands as if it were the
4922 union of the cv-qualification of the operands.
4924 The standard is not clear about what to do in this
4925 circumstance. For example, if the first operand has type
4926 "const X" and the second operand has a user-defined
4927 conversion to "volatile X", what is the type of the second
4928 operand after this step? Making it be "const X" (matching
4929 the first operand) seems wrong, as that discards the
4930 qualification without actually performing a copy. Leaving it
4931 as "volatile X" seems wrong as that will result in the
4932 conditional expression failing altogether, even though,
4933 according to this step, the one operand could be converted to
4934 the type of the other. */
4936 && CLASS_TYPE_P (arg2_type
)
4937 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
4938 arg2_type
= arg3_type
=
4939 cp_build_qualified_type (arg2_type
,
4940 cp_type_quals (arg2_type
)
4941 | cp_type_quals (arg3_type
));
4946 If the second and third operands are glvalues of the same value
4947 category and have the same type, the result is of that type and
4949 if (((real_lvalue_p (arg2
) && real_lvalue_p (arg3
))
4950 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
4951 && same_type_p (arg2_type
, arg3_type
))
4953 result_type
= arg2_type
;
4954 arg2
= mark_lvalue_use (arg2
);
4955 arg3
= mark_lvalue_use (arg3
);
4956 goto valid_operands
;
4961 Otherwise, the result is an rvalue. If the second and third
4962 operand do not have the same type, and either has (possibly
4963 cv-qualified) class type, overload resolution is used to
4964 determine the conversions (if any) to be applied to the operands
4965 (_over.match.oper_, _over.built_). */
4967 if (!same_type_p (arg2_type
, arg3_type
)
4968 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
4974 /* Rearrange the arguments so that add_builtin_candidate only has
4975 to know about two args. In build_builtin_candidate, the
4976 arguments are unscrambled. */
4980 add_builtin_candidates (&candidates
,
4983 ansi_opname (COND_EXPR
),
4985 LOOKUP_NORMAL
, complain
);
4989 If the overload resolution fails, the program is
4991 candidates
= splice_viable (candidates
, false, &any_viable_p
);
4994 if (complain
& tf_error
)
4995 error_at (loc
, "operands to ?: have different types %qT and %qT",
4996 arg2_type
, arg3_type
);
4997 return error_mark_node
;
4999 cand
= tourney (candidates
, complain
);
5002 if (complain
& tf_error
)
5004 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5005 print_z_candidates (loc
, candidates
);
5007 return error_mark_node
;
5012 Otherwise, the conversions thus determined are applied, and
5013 the converted operands are used in place of the original
5014 operands for the remainder of this section. */
5015 conv
= cand
->convs
[0];
5016 arg1
= convert_like (conv
, arg1
, complain
);
5017 conv
= cand
->convs
[1];
5018 arg2
= convert_like (conv
, arg2
, complain
);
5019 arg2_type
= TREE_TYPE (arg2
);
5020 conv
= cand
->convs
[2];
5021 arg3
= convert_like (conv
, arg3
, complain
);
5022 arg3_type
= TREE_TYPE (arg3
);
5027 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5028 and function-to-pointer (_conv.func_) standard conversions are
5029 performed on the second and third operands.
5031 We need to force the lvalue-to-rvalue conversion here for class types,
5032 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5033 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5036 arg2
= force_rvalue (arg2
, complain
);
5037 if (!CLASS_TYPE_P (arg2_type
))
5038 arg2_type
= TREE_TYPE (arg2
);
5040 arg3
= force_rvalue (arg3
, complain
);
5041 if (!CLASS_TYPE_P (arg3_type
))
5042 arg3_type
= TREE_TYPE (arg3
);
5044 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5045 return error_mark_node
;
5049 After those conversions, one of the following shall hold:
5051 --The second and third operands have the same type; the result is of
5053 if (same_type_p (arg2_type
, arg3_type
))
5054 result_type
= arg2_type
;
5057 --The second and third operands have arithmetic or enumeration
5058 type; the usual arithmetic conversions are performed to bring
5059 them to a common type, and the result is of that type. */
5060 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5061 || UNSCOPED_ENUM_P (arg2_type
))
5062 && (ARITHMETIC_TYPE_P (arg3_type
)
5063 || UNSCOPED_ENUM_P (arg3_type
)))
5065 /* In this case, there is always a common type. */
5066 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5068 if (complain
& tf_warning
)
5069 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5070 "implicit conversion from %qT to %qT to "
5071 "match other result of conditional",
5074 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5075 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5077 if (TREE_CODE (orig_arg2
) == CONST_DECL
5078 && TREE_CODE (orig_arg3
) == CONST_DECL
5079 && DECL_CONTEXT (orig_arg2
) == DECL_CONTEXT (orig_arg3
))
5080 /* Two enumerators from the same enumeration can have different
5081 types when the enumeration is still being defined. */;
5082 else if (complain
& tf_warning
)
5083 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5084 "conditional expression: %qT vs %qT",
5085 arg2_type
, arg3_type
);
5087 else if (extra_warnings
5088 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5089 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5090 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5091 && !same_type_p (arg2_type
,
5092 type_promotes_to (arg3_type
)))))
5094 if (complain
& tf_warning
)
5095 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5096 "conditional expression");
5099 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5100 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5104 --The second and third operands have pointer type, or one has
5105 pointer type and the other is a null pointer constant; pointer
5106 conversions (_conv.ptr_) and qualification conversions
5107 (_conv.qual_) are performed to bring them to their composite
5108 pointer type (_expr.rel_). The result is of the composite
5111 --The second and third operands have pointer to member type, or
5112 one has pointer to member type and the other is a null pointer
5113 constant; pointer to member conversions (_conv.mem_) and
5114 qualification conversions (_conv.qual_) are performed to bring
5115 them to a common type, whose cv-qualification shall match the
5116 cv-qualification of either the second or the third operand.
5117 The result is of the common type. */
5118 else if ((null_ptr_cst_p (arg2
)
5119 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5120 || (null_ptr_cst_p (arg3
)
5121 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5122 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5123 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5124 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5126 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5127 arg3
, CPO_CONDITIONAL_EXPR
,
5129 if (result_type
== error_mark_node
)
5130 return error_mark_node
;
5131 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5132 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5137 if (complain
& tf_error
)
5138 error_at (loc
, "operands to ?: have different types %qT and %qT",
5139 arg2_type
, arg3_type
);
5140 return error_mark_node
;
5143 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5144 return error_mark_node
;
5147 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5148 if (!cp_unevaluated_operand
)
5149 /* Avoid folding within decltype (c++/42013) and noexcept. */
5150 result
= fold_if_not_in_template (result
);
5152 /* We can't use result_type below, as fold might have returned a
5157 /* Expand both sides into the same slot, hopefully the target of
5158 the ?: expression. We used to check for TARGET_EXPRs here,
5159 but now we sometimes wrap them in NOP_EXPRs so the test would
5161 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5162 result
= get_target_expr_sfinae (result
, complain
);
5163 /* If this expression is an rvalue, but might be mistaken for an
5164 lvalue, we must add a NON_LVALUE_EXPR. */
5165 result
= rvalue (result
);
5168 result
= force_paren_expr (result
);
5173 /* Wrapper for above. */
5176 build_conditional_expr (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
5177 tsubst_flags_t complain
)
5180 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5181 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5182 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5186 /* OPERAND is an operand to an expression. Perform necessary steps
5187 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5191 prep_operand (tree operand
)
5195 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5196 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5197 /* Make sure the template type is instantiated now. */
5198 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5204 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5205 OVERLOAD) to the CANDIDATES, returning an updated list of
5206 CANDIDATES. The ARGS are the arguments provided to the call;
5207 if FIRST_ARG is non-null it is the implicit object argument,
5208 otherwise the first element of ARGS is used if needed. The
5209 EXPLICIT_TARGS are explicit template arguments provided.
5210 TEMPLATE_ONLY is true if only template functions should be
5211 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5212 add_function_candidate. */
5215 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5217 tree explicit_targs
, bool template_only
,
5218 tree conversion_path
, tree access_path
,
5220 struct z_candidate
**candidates
,
5221 tsubst_flags_t complain
)
5224 const vec
<tree
, va_gc
> *non_static_args
;
5225 bool check_list_ctor
;
5226 bool check_converting
;
5227 unification_kind_t strict
;
5233 /* Precalculate special handling of constructors and conversion ops. */
5234 fn
= OVL_CURRENT (fns
);
5235 if (DECL_CONV_FN_P (fn
))
5237 check_list_ctor
= false;
5238 check_converting
= !!(flags
& LOOKUP_ONLYCONVERTING
);
5239 if (flags
& LOOKUP_NO_CONVERSION
)
5240 /* We're doing return_type(x). */
5241 strict
= DEDUCE_CONV
;
5243 /* We're doing x.operator return_type(). */
5244 strict
= DEDUCE_EXACT
;
5245 /* [over.match.funcs] For conversion functions, the function
5246 is considered to be a member of the class of the implicit
5247 object argument for the purpose of defining the type of
5248 the implicit object parameter. */
5249 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5253 if (DECL_CONSTRUCTOR_P (fn
))
5255 check_list_ctor
= !!(flags
& LOOKUP_LIST_ONLY
);
5256 /* For list-initialization we consider explicit constructors
5257 and complain if one is chosen. */
5259 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5260 == LOOKUP_ONLYCONVERTING
);
5264 check_list_ctor
= false;
5265 check_converting
= false;
5267 strict
= DEDUCE_CALL
;
5268 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5272 non_static_args
= args
;
5274 /* Delay creating the implicit this parameter until it is needed. */
5275 non_static_args
= NULL
;
5277 for (; fns
; fns
= OVL_NEXT (fns
))
5280 const vec
<tree
, va_gc
> *fn_args
;
5282 fn
= OVL_CURRENT (fns
);
5284 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5286 if (check_list_ctor
&& !is_list_ctor (fn
))
5289 /* Figure out which set of arguments to use. */
5290 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5292 /* If this function is a non-static member and we didn't get an
5293 implicit object argument, move it out of args. */
5294 if (first_arg
== NULL_TREE
)
5298 vec
<tree
, va_gc
> *tempvec
;
5299 vec_alloc (tempvec
, args
->length () - 1);
5300 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5301 tempvec
->quick_push (arg
);
5302 non_static_args
= tempvec
;
5303 first_arg
= (*args
)[0];
5306 fn_first_arg
= first_arg
;
5307 fn_args
= non_static_args
;
5311 /* Otherwise, just use the list of arguments provided. */
5312 fn_first_arg
= NULL_TREE
;
5316 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5317 add_template_candidate (candidates
,
5329 else if (!template_only
)
5330 add_function_candidate (candidates
,
5343 build_new_op_1 (location_t loc
, enum tree_code code
, int flags
, tree arg1
,
5344 tree arg2
, tree arg3
, tree
*overload
, tsubst_flags_t complain
)
5346 struct z_candidate
*candidates
= 0, *cand
;
5347 vec
<tree
, va_gc
> *arglist
;
5350 tree result
= NULL_TREE
;
5351 bool result_valid_p
= false;
5352 enum tree_code code2
= NOP_EXPR
;
5353 enum tree_code code_orig_arg1
= ERROR_MARK
;
5354 enum tree_code code_orig_arg2
= ERROR_MARK
;
5360 if (error_operand_p (arg1
)
5361 || error_operand_p (arg2
)
5362 || error_operand_p (arg3
))
5363 return error_mark_node
;
5365 if (code
== MODIFY_EXPR
)
5367 code2
= TREE_CODE (arg3
);
5369 fnname
= ansi_assopname (code2
);
5372 fnname
= ansi_opname (code
);
5374 arg1
= prep_operand (arg1
);
5376 bool memonly
= false;
5381 case VEC_DELETE_EXPR
:
5383 /* Use build_op_new_call and build_op_delete_call instead. */
5387 /* Use build_op_call instead. */
5390 case TRUTH_ORIF_EXPR
:
5391 case TRUTH_ANDIF_EXPR
:
5392 case TRUTH_AND_EXPR
:
5394 /* These are saved for the sake of warn_logical_operator. */
5395 code_orig_arg1
= TREE_CODE (arg1
);
5396 code_orig_arg2
= TREE_CODE (arg2
);
5404 /* These are saved for the sake of maybe_warn_bool_compare. */
5405 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5406 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5409 /* =, ->, [], () must be non-static member functions. */
5411 if (code2
!= NOP_EXPR
)
5422 arg2
= prep_operand (arg2
);
5423 arg3
= prep_operand (arg3
);
5425 if (code
== COND_EXPR
)
5426 /* Use build_conditional_expr instead. */
5428 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5429 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5432 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5433 arg2
= integer_zero_node
;
5435 vec_alloc (arglist
, 3);
5436 arglist
->quick_push (arg1
);
5437 if (arg2
!= NULL_TREE
)
5438 arglist
->quick_push (arg2
);
5439 if (arg3
!= NULL_TREE
)
5440 arglist
->quick_push (arg3
);
5442 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5443 p
= conversion_obstack_alloc (0);
5445 /* Add namespace-scope operators to the list of functions to
5448 add_candidates (lookup_function_nonclass (fnname
, arglist
,
5450 NULL_TREE
, arglist
, NULL_TREE
,
5451 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5452 flags
, &candidates
, complain
);
5456 args
[2] = NULL_TREE
;
5458 /* Add class-member operators to the candidate set. */
5459 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5463 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5464 if (fns
== error_mark_node
)
5466 result
= error_mark_node
;
5467 goto user_defined_result_ready
;
5470 add_candidates (BASELINK_FUNCTIONS (fns
),
5471 NULL_TREE
, arglist
, NULL_TREE
,
5473 BASELINK_BINFO (fns
),
5474 BASELINK_ACCESS_BINFO (fns
),
5475 flags
, &candidates
, complain
);
5477 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5478 only non-member functions that have type T1 or reference to
5479 cv-qualified-opt T1 for the first argument, if the first argument
5480 has an enumeration type, or T2 or reference to cv-qualified-opt
5481 T2 for the second argument, if the second argument has an
5482 enumeration type. Filter out those that don't match. */
5483 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5485 struct z_candidate
**candp
, **next
;
5487 for (candp
= &candidates
; *candp
; candp
= next
)
5489 tree parmlist
, parmtype
;
5490 int i
, nargs
= (arg2
? 2 : 1);
5495 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5497 for (i
= 0; i
< nargs
; ++i
)
5499 parmtype
= TREE_VALUE (parmlist
);
5501 if (TREE_CODE (parmtype
) == REFERENCE_TYPE
)
5502 parmtype
= TREE_TYPE (parmtype
);
5503 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5504 && (same_type_ignoring_top_level_qualifiers_p
5505 (TREE_TYPE (args
[i
]), parmtype
)))
5508 parmlist
= TREE_CHAIN (parmlist
);
5511 /* No argument has an appropriate type, so remove this
5512 candidate function from the list. */
5515 *candp
= cand
->next
;
5521 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5528 /* For these, the built-in candidates set is empty
5529 [over.match.oper]/3. We don't want non-strict matches
5530 because exact matches are always possible with built-in
5531 operators. The built-in candidate set for COMPONENT_REF
5532 would be empty too, but since there are no such built-in
5533 operators, we accept non-strict matches for them. */
5542 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5547 case POSTINCREMENT_EXPR
:
5548 case POSTDECREMENT_EXPR
:
5549 /* Don't try anything fancy if we're not allowed to produce
5551 if (!(complain
& tf_error
))
5552 return error_mark_node
;
5554 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5555 distinguish between prefix and postfix ++ and
5556 operator++() was used for both, so we allow this with
5560 const char *msg
= (flag_permissive
)
5561 ? G_("no %<%D(int)%> declared for postfix %qs,"
5562 " trying prefix operator instead")
5563 : G_("no %<%D(int)%> declared for postfix %qs");
5564 permerror (loc
, msg
, fnname
, operator_name_info
[code
].name
);
5567 if (!flag_permissive
)
5568 return error_mark_node
;
5570 if (code
== POSTINCREMENT_EXPR
)
5571 code
= PREINCREMENT_EXPR
;
5573 code
= PREDECREMENT_EXPR
;
5574 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5575 NULL_TREE
, overload
, complain
);
5578 /* The caller will deal with these. */
5583 result_valid_p
= true;
5587 if (complain
& tf_error
)
5589 /* If one of the arguments of the operator represents
5590 an invalid use of member function pointer, try to report
5591 a meaningful error ... */
5592 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
5593 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
5594 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
5595 /* We displayed the error message. */;
5598 /* ... Otherwise, report the more generic
5599 "no matching operator found" error */
5600 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
5601 print_z_candidates (loc
, candidates
);
5604 result
= error_mark_node
;
5610 cand
= tourney (candidates
, complain
);
5613 if (complain
& tf_error
)
5615 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
5616 print_z_candidates (loc
, candidates
);
5618 result
= error_mark_node
;
5620 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
5623 *overload
= cand
->fn
;
5625 if (resolve_args (arglist
, complain
) == NULL
)
5626 result
= error_mark_node
;
5628 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
5632 /* Give any warnings we noticed during overload resolution. */
5633 if (cand
->warnings
&& (complain
& tf_warning
))
5635 struct candidate_warning
*w
;
5636 for (w
= cand
->warnings
; w
; w
= w
->next
)
5637 joust (cand
, w
->loser
, 1, complain
);
5640 /* Check for comparison of different enum types. */
5649 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
5650 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
5651 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
5652 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
5653 && (complain
& tf_warning
))
5655 warning (OPT_Wenum_compare
,
5656 "comparison between %q#T and %q#T",
5657 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
5664 /* We need to strip any leading REF_BIND so that bitfields
5665 don't cause errors. This should not remove any important
5666 conversions, because builtins don't apply to class
5667 objects directly. */
5668 conv
= cand
->convs
[0];
5669 if (conv
->kind
== ck_ref_bind
)
5670 conv
= next_conversion (conv
);
5671 arg1
= convert_like (conv
, arg1
, complain
);
5675 conv
= cand
->convs
[1];
5676 if (conv
->kind
== ck_ref_bind
)
5677 conv
= next_conversion (conv
);
5679 arg2
= decay_conversion (arg2
, complain
);
5681 /* We need to call warn_logical_operator before
5682 converting arg2 to a boolean_type, but after
5683 decaying an enumerator to its value. */
5684 if (complain
& tf_warning
)
5685 warn_logical_operator (loc
, code
, boolean_type_node
,
5686 code_orig_arg1
, arg1
,
5687 code_orig_arg2
, arg2
);
5689 arg2
= convert_like (conv
, arg2
, complain
);
5693 conv
= cand
->convs
[2];
5694 if (conv
->kind
== ck_ref_bind
)
5695 conv
= next_conversion (conv
);
5696 arg3
= convert_like (conv
, arg3
, complain
);
5702 user_defined_result_ready
:
5704 /* Free all the conversions we allocated. */
5705 obstack_free (&conversion_obstack
, p
);
5707 if (result
|| result_valid_p
)
5714 return cp_build_modify_expr (arg1
, code2
, arg2
, complain
);
5717 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
5719 case TRUTH_ANDIF_EXPR
:
5720 case TRUTH_ORIF_EXPR
:
5721 case TRUTH_AND_EXPR
:
5723 if (complain
& tf_warning
)
5724 warn_logical_operator (loc
, code
, boolean_type_node
,
5725 code_orig_arg1
, arg1
, code_orig_arg2
, arg2
);
5733 if ((complain
& tf_warning
)
5734 && ((code_orig_arg1
== BOOLEAN_TYPE
)
5735 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
5736 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
5737 if (complain
& tf_warning
&& warn_tautological_compare
)
5738 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
5743 case TRUNC_DIV_EXPR
:
5748 case TRUNC_MOD_EXPR
:
5752 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
5754 case UNARY_PLUS_EXPR
:
5757 case TRUTH_NOT_EXPR
:
5758 case PREINCREMENT_EXPR
:
5759 case POSTINCREMENT_EXPR
:
5760 case PREDECREMENT_EXPR
:
5761 case POSTDECREMENT_EXPR
:
5765 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
5768 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
5771 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
5775 /* The caller will deal with these. */
5787 /* Wrapper for above. */
5790 build_new_op (location_t loc
, enum tree_code code
, int flags
,
5791 tree arg1
, tree arg2
, tree arg3
,
5792 tree
*overload
, tsubst_flags_t complain
)
5795 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5796 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
5797 overload
, complain
);
5798 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5802 /* Returns true if FN has two parameters, of which the second has type
5806 second_parm_is_size_t (tree fn
)
5808 tree t
= FUNCTION_ARG_CHAIN (fn
);
5810 && same_type_p (TREE_VALUE (t
), size_type_node
)
5811 && TREE_CHAIN (t
) == void_list_node
);
5814 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5815 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5818 non_placement_deallocation_fn_p (tree t
)
5820 /* A template instance is never a usual deallocation function,
5821 regardless of its signature. */
5822 if (TREE_CODE (t
) == TEMPLATE_DECL
5823 || primary_template_instantiation_p (t
))
5826 /* If a class T has a member deallocation function named operator delete
5827 with exactly one parameter, then that function is a usual
5828 (non-placement) deallocation function. If class T does not declare
5829 such an operator delete but does declare a member deallocation
5830 function named operator delete with exactly two parameters, the second
5831 of which has type std::size_t (18.2), then this function is a usual
5832 deallocation function. */
5833 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
5834 if (FUNCTION_ARG_CHAIN (t
) == void_list_node
5835 || ((!global
|| flag_sized_deallocation
)
5836 && second_parm_is_size_t (t
)))
5841 /* Build a call to operator delete. This has to be handled very specially,
5842 because the restrictions on what signatures match are different from all
5843 other call instances. For a normal delete, only a delete taking (void *)
5844 or (void *, size_t) is accepted. For a placement delete, only an exact
5845 match with the placement new is accepted.
5847 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5848 ADDR is the pointer to be deleted.
5849 SIZE is the size of the memory block to be deleted.
5850 GLOBAL_P is true if the delete-expression should not consider
5851 class-specific delete operators.
5852 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5854 If this call to "operator delete" is being generated as part to
5855 deallocate memory allocated via a new-expression (as per [expr.new]
5856 which requires that if the initialization throws an exception then
5857 we call a deallocation function), then ALLOC_FN is the allocation
5861 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
5862 bool global_p
, tree placement
,
5863 tree alloc_fn
, tsubst_flags_t complain
)
5865 tree fn
= NULL_TREE
;
5866 tree fns
, fnname
, type
, t
;
5868 if (addr
== error_mark_node
)
5869 return error_mark_node
;
5871 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
5873 fnname
= ansi_opname (code
);
5875 if (CLASS_TYPE_P (type
)
5876 && COMPLETE_TYPE_P (complete_type (type
))
5880 If the result of the lookup is ambiguous or inaccessible, or if
5881 the lookup selects a placement deallocation function, the
5882 program is ill-formed.
5884 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5886 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
5887 if (fns
== error_mark_node
)
5888 return error_mark_node
;
5893 if (fns
== NULL_TREE
)
5894 fns
= lookup_name_nonclass (fnname
);
5896 /* Strip const and volatile from addr. */
5897 addr
= cp_convert (ptr_type_node
, addr
, complain
);
5901 /* "A declaration of a placement deallocation function matches the
5902 declaration of a placement allocation function if it has the same
5903 number of parameters and, after parameter transformations (8.3.5),
5904 all parameter types except the first are identical."
5906 So we build up the function type we want and ask instantiate_type
5907 to get it for us. */
5908 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
5909 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
5910 t
= build_function_type (void_type_node
, t
);
5912 fn
= instantiate_type (t
, fns
, tf_none
);
5913 if (fn
== error_mark_node
)
5916 if (BASELINK_P (fn
))
5917 fn
= BASELINK_FUNCTIONS (fn
);
5919 /* "If the lookup finds the two-parameter form of a usual deallocation
5920 function (3.7.4.2) and that function, considered as a placement
5921 deallocation function, would have been selected as a match for the
5922 allocation function, the program is ill-formed." */
5923 if (second_parm_is_size_t (fn
))
5926 = G_("exception cleanup for this placement new selects "
5927 "non-placement operator delete");
5929 = G_("%qD is a usual (non-placement) deallocation "
5930 "function in C++14 (or with -fsized-deallocation)");
5932 /* But if the class has an operator delete (void *), then that is
5933 the usual deallocation function, so we shouldn't complain
5934 about using the operator delete (void *, size_t). */
5935 if (DECL_CLASS_SCOPE_P (fn
))
5936 for (t
= BASELINK_P (fns
) ? BASELINK_FUNCTIONS (fns
) : fns
;
5937 t
; t
= OVL_NEXT (t
))
5939 tree elt
= OVL_CURRENT (t
);
5940 if (non_placement_deallocation_fn_p (elt
)
5941 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
5944 /* Before C++14 a two-parameter global deallocation function is
5945 always a placement deallocation function, but warn if
5947 else if (!flag_sized_deallocation
)
5949 if ((complain
& tf_warning
)
5950 && warning (OPT_Wc__14_compat
, msg1
))
5951 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
5955 if (complain
& tf_warning_or_error
)
5957 if (permerror (input_location
, msg1
))
5959 /* Only mention C++14 for namespace-scope delete. */
5960 if (DECL_NAMESPACE_SCOPE_P (fn
))
5961 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
5963 inform (DECL_SOURCE_LOCATION (fn
),
5964 "%qD is a usual (non-placement) deallocation "
5969 return error_mark_node
;
5974 /* "Any non-placement deallocation function matches a non-placement
5975 allocation function. If the lookup finds a single matching
5976 deallocation function, that function will be called; otherwise, no
5977 deallocation function will be called." */
5978 for (t
= BASELINK_P (fns
) ? BASELINK_FUNCTIONS (fns
) : fns
;
5979 t
; t
= OVL_NEXT (t
))
5981 tree elt
= OVL_CURRENT (t
);
5982 if (non_placement_deallocation_fn_p (elt
))
5985 /* "If a class T has a member deallocation function named
5986 operator delete with exactly one parameter, then that
5987 function is a usual (non-placement) deallocation
5988 function. If class T does not declare such an operator
5989 delete but does declare a member deallocation function named
5990 operator delete with exactly two parameters, the second of
5991 which has type std::size_t (18.2), then this function is a
5992 usual deallocation function."
5994 So in a class (void*) beats (void*, size_t). */
5995 if (DECL_CLASS_SCOPE_P (fn
))
5997 if (FUNCTION_ARG_CHAIN (fn
) == void_list_node
)
6000 /* At global scope (in C++14 and above) the rules are different:
6002 If deallocation function lookup finds both a usual
6003 deallocation function with only a pointer parameter and a
6004 usual deallocation function with both a pointer parameter
6005 and a size parameter, the function to be called is selected
6008 * If the type is complete and if, for the second alternative
6009 (delete array) only, the operand is a pointer to a class
6010 type with a non-trivial destructor or a (possibly
6011 multi-dimensional) array thereof, the function with two
6012 parameters is selected.
6014 * Otherwise, it is unspecified which of the two deallocation
6015 functions is selected. */
6018 bool want_size
= COMPLETE_TYPE_P (type
);
6019 if (code
== VEC_DELETE_EXPR
6020 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6021 /* We need a cookie to determine the array size. */
6023 bool have_size
= (FUNCTION_ARG_CHAIN (fn
) != void_list_node
);
6024 if (want_size
== have_size
)
6030 /* If we have a matching function, call it. */
6033 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6035 /* If the FN is a member function, make sure that it is
6037 if (BASELINK_P (fns
))
6038 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6041 /* Core issue 901: It's ok to new a type with deleted delete. */
6042 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6047 /* The placement args might not be suitable for overload
6048 resolution at this point, so build the call directly. */
6049 int nargs
= call_expr_nargs (placement
);
6050 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6053 for (i
= 1; i
< nargs
; i
++)
6054 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6055 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6056 return error_mark_node
;
6057 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6062 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6063 args
->quick_push (addr
);
6064 if (FUNCTION_ARG_CHAIN (fn
) != void_list_node
)
6065 args
->quick_push (size
);
6066 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6067 release_tree_vector (args
);
6074 If no unambiguous matching deallocation function can be found,
6075 propagating the exception does not cause the object's memory to
6079 if ((complain
& tf_warning
)
6081 warning (0, "no corresponding deallocation function for %qD",
6086 if (complain
& tf_error
)
6087 error ("no suitable %<operator %s%> for %qT",
6088 operator_name_info
[(int)code
].name
, type
);
6089 return error_mark_node
;
6092 /* If the current scope isn't allowed to access DECL along
6093 BASETYPE_PATH, give an error. The most derived class in
6094 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6095 the declaration to use in the error diagnostic. */
6098 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6099 tsubst_flags_t complain
)
6101 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6103 if (!accessible_p (basetype_path
, decl
, true))
6105 if (complain
& tf_error
)
6107 if (TREE_PRIVATE (decl
))
6109 error ("%q#D is private within this context", diag_decl
);
6110 inform (DECL_SOURCE_LOCATION (diag_decl
),
6111 "declared private here");
6113 else if (TREE_PROTECTED (decl
))
6115 error ("%q#D is protected within this context", diag_decl
);
6116 inform (DECL_SOURCE_LOCATION (diag_decl
),
6117 "declared protected here");
6121 error ("%q#D is inaccessible within this context", diag_decl
);
6122 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6131 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6132 bitwise or of LOOKUP_* values. If any errors are warnings are
6133 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6134 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6138 build_temp (tree expr
, tree type
, int flags
,
6139 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6142 vec
<tree
, va_gc
> *args
;
6144 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6145 args
= make_tree_vector_single (expr
);
6146 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6147 &args
, type
, flags
, complain
);
6148 release_tree_vector (args
);
6149 if (warningcount
+ werrorcount
> savew
)
6150 *diagnostic_kind
= DK_WARNING
;
6151 else if (errorcount
> savee
)
6152 *diagnostic_kind
= DK_ERROR
;
6154 *diagnostic_kind
= DK_UNSPECIFIED
;
6158 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6159 EXPR is implicitly converted to type TOTYPE.
6160 FN and ARGNUM are used for diagnostics. */
6163 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6165 /* Issue warnings about peculiar, but valid, uses of NULL. */
6166 if (expr
== null_node
&& TREE_CODE (totype
) != BOOLEAN_TYPE
6167 && ARITHMETIC_TYPE_P (totype
))
6169 source_location loc
=
6170 expansion_point_location_if_in_system_header (input_location
);
6173 warning_at (loc
, OPT_Wconversion_null
,
6174 "passing NULL to non-pointer argument %P of %qD",
6177 warning_at (loc
, OPT_Wconversion_null
,
6178 "converting to non-pointer type %qT from NULL", totype
);
6181 /* Issue warnings if "false" is converted to a NULL pointer */
6182 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6183 && TYPE_PTR_P (totype
))
6186 warning_at (input_location
, OPT_Wconversion_null
,
6187 "converting %<false%> to pointer type for argument %P "
6188 "of %qD", argnum
, fn
);
6190 warning_at (input_location
, OPT_Wconversion_null
,
6191 "converting %<false%> to pointer type %qT", totype
);
6195 /* We gave a diagnostic during a conversion. If this was in the second
6196 standard conversion sequence of a user-defined conversion sequence, say
6197 which user-defined conversion. */
6200 maybe_print_user_conv_context (conversion
*convs
)
6202 if (convs
->user_conv_p
)
6203 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6204 if (t
->kind
== ck_user
)
6206 print_z_candidate (0, " after user-defined conversion:",
6212 /* Perform the conversions in CONVS on the expression EXPR. FN and
6213 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6214 indicates the `this' argument of a method. INNER is nonzero when
6215 being called to continue a conversion chain. It is negative when a
6216 reference binding will be applied, positive otherwise. If
6217 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6218 conversions will be emitted if appropriate. If C_CAST_P is true,
6219 this conversion is coming from a C-style cast; in that case,
6220 conversions to inaccessible bases are permitted. */
6223 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6224 int inner
, bool issue_conversion_warnings
,
6225 bool c_cast_p
, tsubst_flags_t complain
)
6227 tree totype
= convs
->type
;
6228 diagnostic_t diag_kind
;
6230 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6232 if (convs
->bad_p
&& !(complain
& tf_error
))
6233 return error_mark_node
;
6236 && convs
->kind
!= ck_user
6237 && convs
->kind
!= ck_list
6238 && convs
->kind
!= ck_ambig
6239 && (convs
->kind
!= ck_ref_bind
6240 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6241 && (convs
->kind
!= ck_rvalue
6242 || SCALAR_TYPE_P (totype
))
6243 && convs
->kind
!= ck_base
)
6245 bool complained
= false;
6246 conversion
*t
= convs
;
6248 /* Give a helpful error if this is bad because of excess braces. */
6249 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6250 && SCALAR_TYPE_P (totype
)
6251 && CONSTRUCTOR_NELTS (expr
) > 0
6252 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6254 complained
= permerror (loc
, "too many braces around initializer "
6256 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6257 && CONSTRUCTOR_NELTS (expr
) == 1)
6258 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6261 /* Give a helpful error if this is bad because a conversion to bool
6262 from std::nullptr_t requires direct-initialization. */
6263 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6264 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6265 complained
= permerror (loc
, "converting to %qT from %qT requires "
6266 "direct-initialization",
6267 totype
, TREE_TYPE (expr
));
6269 for (; t
; t
= next_conversion (t
))
6271 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6273 complained
= permerror (loc
, "invalid user-defined conversion "
6274 "from %qT to %qT", TREE_TYPE (expr
),
6277 print_z_candidate (loc
, "candidate is:", t
->cand
);
6278 expr
= convert_like_real (t
, expr
, fn
, argnum
, 1,
6279 /*issue_conversion_warnings=*/false,
6282 if (convs
->kind
== ck_ref_bind
)
6283 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6284 LOOKUP_NORMAL
, NULL_TREE
,
6287 expr
= cp_convert (totype
, expr
, complain
);
6288 if (complained
&& fn
)
6289 inform (DECL_SOURCE_LOCATION (fn
),
6290 " initializing argument %P of %qD", argnum
, fn
);
6293 else if (t
->kind
== ck_user
|| !t
->bad_p
)
6295 expr
= convert_like_real (t
, expr
, fn
, argnum
, 1,
6296 /*issue_conversion_warnings=*/false,
6301 else if (t
->kind
== ck_ambig
)
6302 return convert_like_real (t
, expr
, fn
, argnum
, 1,
6303 /*issue_conversion_warnings=*/false,
6306 else if (t
->kind
== ck_identity
)
6310 complained
= permerror (loc
, "invalid conversion from %qT to %qT",
6311 TREE_TYPE (expr
), totype
);
6312 if (complained
&& fn
)
6313 inform (DECL_SOURCE_LOCATION (fn
),
6314 " initializing argument %P of %qD", argnum
, fn
);
6316 return cp_convert (totype
, expr
, complain
);
6319 if (issue_conversion_warnings
&& (complain
& tf_warning
))
6320 conversion_null_warnings (totype
, expr
, fn
, argnum
);
6322 switch (convs
->kind
)
6326 struct z_candidate
*cand
= convs
->cand
;
6327 tree convfn
= cand
->fn
;
6330 /* If we're initializing from {}, it's value-initialization. Note
6331 that under the resolution of core 1630, value-initialization can
6332 use explicit constructors. */
6333 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6334 && CONSTRUCTOR_NELTS (expr
) == 0
6335 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
6337 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
6338 expr
= build_value_init (totype
, complain
);
6339 expr
= get_target_expr_sfinae (expr
, complain
);
6340 if (expr
!= error_mark_node
)
6342 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6343 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
6348 /* When converting from an init list we consider explicit
6349 constructors, but actually trying to call one is an error. */
6350 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
6351 /* Unless this is for direct-list-initialization. */
6352 && !DIRECT_LIST_INIT_P (expr
))
6354 if (!(complain
& tf_error
))
6355 return error_mark_node
;
6356 error ("converting to %qT from initializer list would use "
6357 "explicit constructor %qD", totype
, convfn
);
6360 expr
= mark_rvalue_use (expr
);
6362 /* Set user_conv_p on the argument conversions, so rvalue/base
6363 handling knows not to allow any more UDCs. */
6364 for (i
= 0; i
< cand
->num_convs
; ++i
)
6365 cand
->convs
[i
]->user_conv_p
= true;
6367 expr
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
6369 /* If this is a constructor or a function returning an aggr type,
6370 we need to build up a TARGET_EXPR. */
6371 if (DECL_CONSTRUCTOR_P (convfn
))
6373 expr
= build_cplus_new (totype
, expr
, complain
);
6375 /* Remember that this was list-initialization. */
6376 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
6377 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6383 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
6385 int nelts
= CONSTRUCTOR_NELTS (expr
);
6387 expr
= build_value_init (totype
, complain
);
6388 else if (nelts
== 1)
6389 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6393 expr
= mark_rvalue_use (expr
);
6395 if (type_unknown_p (expr
))
6396 expr
= instantiate_type (totype
, expr
, complain
);
6397 /* Convert a constant to its underlying value, unless we are
6398 about to bind it to a reference, in which case we need to
6399 leave it as an lvalue. */
6402 expr
= scalar_constant_value (expr
);
6403 if (expr
== null_node
&& INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
6404 /* If __null has been converted to an integer type, we do not
6405 want to warn about uses of EXPR as an integer, rather than
6407 expr
= build_int_cst (totype
, 0);
6411 /* We leave bad_p off ck_ambig because overload resolution considers
6412 it valid, it just fails when we try to perform it. So we need to
6413 check complain here, too. */
6414 if (complain
& tf_error
)
6416 /* Call build_user_type_conversion again for the error. */
6417 build_user_type_conversion (totype
, convs
->u
.expr
, LOOKUP_NORMAL
,
6420 inform (DECL_SOURCE_LOCATION (fn
),
6421 " initializing argument %P of %qD", argnum
, fn
);
6423 return error_mark_node
;
6427 /* Conversion to std::initializer_list<T>. */
6428 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
6429 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
6430 unsigned len
= CONSTRUCTOR_NELTS (expr
);
6431 tree array
, val
, field
;
6432 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
6435 /* Convert all the elements. */
6436 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
6438 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
, argnum
,
6439 1, false, false, complain
);
6440 if (sub
== error_mark_node
)
6442 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
6443 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
6444 return error_mark_node
;
6445 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
), NULL_TREE
, sub
);
6446 if (!TREE_CONSTANT (sub
))
6447 TREE_CONSTANT (new_ctor
) = false;
6449 /* Build up the array. */
6450 elttype
= cp_build_qualified_type
6451 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
6452 array
= build_array_of_n_type (elttype
, len
);
6453 array
= finish_compound_literal (array
, new_ctor
, complain
);
6454 /* Take the address explicitly rather than via decay_conversion
6455 to avoid the error about taking the address of a temporary. */
6456 array
= cp_build_addr_expr (array
, complain
);
6457 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
6458 if (array
== error_mark_node
)
6459 return error_mark_node
;
6461 /* Build up the initializer_list object. */
6462 totype
= complete_type (totype
);
6463 field
= next_initializable_field (TYPE_FIELDS (totype
));
6464 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
6465 field
= next_initializable_field (DECL_CHAIN (field
));
6466 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
6467 new_ctor
= build_constructor (totype
, vec
);
6468 return get_target_expr_sfinae (new_ctor
, complain
);
6472 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
6474 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6475 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
6476 real
= perform_implicit_conversion (TREE_TYPE (totype
),
6478 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
6480 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
6481 return fold_if_not_in_template (expr
);
6483 expr
= reshape_init (totype
, expr
, complain
);
6484 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
6486 if (expr
!= error_mark_node
)
6487 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6494 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
6495 convs
->kind
== ck_ref_bind
? -1 : 1,
6496 convs
->kind
== ck_ref_bind
? issue_conversion_warnings
: false,
6499 if (expr
== error_mark_node
)
6500 return error_mark_node
;
6502 switch (convs
->kind
)
6505 expr
= decay_conversion (expr
, complain
);
6506 if (expr
== error_mark_node
)
6507 return error_mark_node
;
6509 if (! MAYBE_CLASS_TYPE_P (totype
))
6511 /* Else fall through. */
6513 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
6515 /* We are going to bind a reference directly to a base-class
6516 subobject of EXPR. */
6517 /* Build an expression for `*((base*) &expr)'. */
6518 expr
= convert_to_base (expr
, totype
,
6519 !c_cast_p
, /*nonnull=*/true, complain
);
6523 /* Copy-initialization where the cv-unqualified version of the source
6524 type is the same class as, or a derived class of, the class of the
6525 destination [is treated as direct-initialization]. [dcl.init] */
6526 flags
= LOOKUP_NORMAL
;
6527 if (convs
->user_conv_p
)
6528 /* This conversion is being done in the context of a user-defined
6529 conversion (i.e. the second step of copy-initialization), so
6530 don't allow any more. */
6531 flags
|= LOOKUP_NO_CONVERSION
;
6533 flags
|= LOOKUP_ONLYCONVERTING
;
6534 if (convs
->rvaluedness_matches_p
)
6535 flags
|= LOOKUP_PREFER_RVALUE
;
6536 if (TREE_CODE (expr
) == TARGET_EXPR
6537 && TARGET_EXPR_LIST_INIT_P (expr
))
6538 /* Copy-list-initialization doesn't actually involve a copy. */
6540 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
6541 if (diag_kind
&& complain
)
6543 maybe_print_user_conv_context (convs
);
6545 inform (DECL_SOURCE_LOCATION (fn
),
6546 " initializing argument %P of %qD", argnum
, fn
);
6549 return build_cplus_new (totype
, expr
, complain
);
6553 tree ref_type
= totype
;
6555 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
6557 tree extype
= TREE_TYPE (expr
);
6558 if (TYPE_REF_IS_RVALUE (ref_type
)
6559 && real_lvalue_p (expr
))
6560 error_at (loc
, "cannot bind %qT lvalue to %qT",
6562 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !real_lvalue_p (expr
)
6563 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
6564 error_at (loc
, "invalid initialization of non-const reference of "
6565 "type %qT from an rvalue of type %qT", totype
, extype
);
6566 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
6567 error_at (loc
, "binding %qT to reference of type %qT "
6568 "discards qualifiers", extype
, totype
);
6571 maybe_print_user_conv_context (convs
);
6573 inform (DECL_SOURCE_LOCATION (fn
),
6574 " initializing argument %P of %qD", argnum
, fn
);
6575 return error_mark_node
;
6578 /* If necessary, create a temporary.
6580 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
6581 that need temporaries, even when their types are reference
6582 compatible with the type of reference being bound, so the
6583 upcoming call to cp_build_addr_expr doesn't fail. */
6584 if (convs
->need_temporary_p
6585 || TREE_CODE (expr
) == CONSTRUCTOR
6586 || TREE_CODE (expr
) == VA_ARG_EXPR
)
6588 /* Otherwise, a temporary of type "cv1 T1" is created and
6589 initialized from the initializer expression using the rules
6590 for a non-reference copy-initialization (8.5). */
6592 tree type
= TREE_TYPE (ref_type
);
6593 cp_lvalue_kind lvalue
= real_lvalue_p (expr
);
6595 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6596 (type
, next_conversion (convs
)->type
));
6597 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
6598 && !TYPE_REF_IS_RVALUE (ref_type
))
6600 /* If the reference is volatile or non-const, we
6601 cannot create a temporary. */
6602 if (lvalue
& clk_bitfield
)
6603 error_at (loc
, "cannot bind bitfield %qE to %qT",
6605 else if (lvalue
& clk_packed
)
6606 error_at (loc
, "cannot bind packed field %qE to %qT",
6609 error_at (loc
, "cannot bind rvalue %qE to %qT",
6611 return error_mark_node
;
6613 /* If the source is a packed field, and we must use a copy
6614 constructor, then building the target expr will require
6615 binding the field to the reference parameter to the
6616 copy constructor, and we'll end up with an infinite
6617 loop. If we can use a bitwise copy, then we'll be
6619 if ((lvalue
& clk_packed
)
6620 && CLASS_TYPE_P (type
)
6621 && type_has_nontrivial_copy_init (type
))
6623 error_at (loc
, "cannot bind packed field %qE to %qT",
6625 return error_mark_node
;
6627 if (lvalue
& clk_bitfield
)
6629 expr
= convert_bitfield_to_declared_type (expr
);
6630 expr
= fold_convert (type
, expr
);
6632 expr
= build_target_expr_with_type (expr
, type
, complain
);
6635 /* Take the address of the thing to which we will bind the
6637 expr
= cp_build_addr_expr (expr
, complain
);
6638 if (expr
== error_mark_node
)
6639 return error_mark_node
;
6641 /* Convert it to a pointer to the type referred to by the
6642 reference. This will adjust the pointer if a derived to
6643 base conversion is being performed. */
6644 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
6646 /* Convert the pointer to the desired reference type. */
6647 return build_nop (ref_type
, expr
);
6651 return decay_conversion (expr
, complain
);
6654 /* ??? Should the address of a transaction-safe pointer point to the TM
6655 clone, and this conversion look up the primary function? */
6656 return build_nop (totype
, expr
);
6659 /* Warn about deprecated conversion if appropriate. */
6660 string_conv_p (totype
, expr
, 1);
6665 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
6666 /*nonnull=*/false, complain
);
6667 return build_nop (totype
, expr
);
6670 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
6671 c_cast_p
, complain
);
6677 if (convs
->check_narrowing
6678 && !check_narrowing (totype
, expr
, complain
))
6679 return error_mark_node
;
6681 if (issue_conversion_warnings
)
6682 expr
= cp_convert_and_check (totype
, expr
, complain
);
6684 expr
= cp_convert (totype
, expr
, complain
);
6689 /* ARG is being passed to a varargs function. Perform any conversions
6690 required. Return the converted value. */
6693 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
6696 location_t loc
= EXPR_LOC_OR_LOC (arg
, input_location
);
6700 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6701 standard conversions are performed. */
6702 arg
= decay_conversion (arg
, complain
);
6703 arg_type
= TREE_TYPE (arg
);
6706 If the argument has integral or enumeration type that is subject
6707 to the integral promotions (_conv.prom_), or a floating point
6708 type that is subject to the floating point promotion
6709 (_conv.fpprom_), the value of the argument is converted to the
6710 promoted type before the call. */
6711 if (TREE_CODE (arg_type
) == REAL_TYPE
6712 && (TYPE_PRECISION (arg_type
)
6713 < TYPE_PRECISION (double_type_node
))
6714 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
6716 if ((complain
& tf_warning
)
6717 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
6718 warning_at (loc
, OPT_Wdouble_promotion
,
6719 "implicit conversion from %qT to %qT when passing "
6720 "argument to function",
6721 arg_type
, double_type_node
);
6722 arg
= convert_to_real (double_type_node
, arg
);
6724 else if (NULLPTR_TYPE_P (arg_type
))
6725 arg
= null_pointer_node
;
6726 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
6728 if (SCOPED_ENUM_P (arg_type
))
6730 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
6732 prom
= cp_perform_integral_promotions (prom
, complain
);
6733 if (abi_version_crosses (6)
6734 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
6735 && (complain
& tf_warning
))
6736 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
6737 "%qT before -fabi-version=6, %qT after", arg_type
,
6738 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
6739 if (!abi_version_at_least (6))
6743 arg
= cp_perform_integral_promotions (arg
, complain
);
6746 arg
= require_complete_type_sfinae (arg
, complain
);
6747 arg_type
= TREE_TYPE (arg
);
6749 if (arg
!= error_mark_node
6750 /* In a template (or ill-formed code), we can have an incomplete type
6751 even after require_complete_type_sfinae, in which case we don't know
6752 whether it has trivial copy or not. */
6753 && COMPLETE_TYPE_P (arg_type
))
6755 /* Build up a real lvalue-to-rvalue conversion in case the
6756 copy constructor is trivial but not callable. */
6757 if (!cp_unevaluated_operand
&& CLASS_TYPE_P (arg_type
))
6758 force_rvalue (arg
, complain
);
6760 /* [expr.call] 5.2.2/7:
6761 Passing a potentially-evaluated argument of class type (Clause 9)
6762 with a non-trivial copy constructor or a non-trivial destructor
6763 with no corresponding parameter is conditionally-supported, with
6764 implementation-defined semantics.
6766 We support it as pass-by-invisible-reference, just like a normal
6769 If the call appears in the context of a sizeof expression,
6770 it is not potentially-evaluated. */
6771 if (cp_unevaluated_operand
== 0
6772 && (type_has_nontrivial_copy_init (arg_type
)
6773 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
)))
6775 if (complain
& tf_warning
)
6776 warning (OPT_Wconditionally_supported
,
6777 "passing objects of non-trivially-copyable "
6778 "type %q#T through %<...%> is conditionally supported",
6780 return cp_build_addr_expr (arg
, complain
);
6787 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6790 build_x_va_arg (source_location loc
, tree expr
, tree type
)
6792 if (processing_template_decl
)
6794 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
6795 SET_EXPR_LOCATION (r
, loc
);
6799 type
= complete_type_or_else (type
, NULL_TREE
);
6801 if (expr
== error_mark_node
|| !type
)
6802 return error_mark_node
;
6804 expr
= mark_lvalue_use (expr
);
6806 if (TREE_CODE (type
) == REFERENCE_TYPE
)
6808 error ("cannot receive reference type %qT through %<...%>", type
);
6809 return error_mark_node
;
6812 if (type_has_nontrivial_copy_init (type
)
6813 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
6815 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
6816 it as pass by invisible reference. */
6817 warning_at (loc
, OPT_Wconditionally_supported
,
6818 "receiving objects of non-trivially-copyable type %q#T "
6819 "through %<...%> is conditionally-supported", type
);
6821 tree ref
= cp_build_reference_type (type
, false);
6822 expr
= build_va_arg (loc
, expr
, ref
);
6823 return convert_from_reference (expr
);
6826 return build_va_arg (loc
, expr
, type
);
6829 /* TYPE has been given to va_arg. Apply the default conversions which
6830 would have happened when passed via ellipsis. Return the promoted
6831 type, or the passed type if there is no change. */
6834 cxx_type_promotes_to (tree type
)
6838 /* Perform the array-to-pointer and function-to-pointer
6840 type
= type_decays_to (type
);
6842 promote
= type_promotes_to (type
);
6843 if (same_type_p (type
, promote
))
6849 /* ARG is a default argument expression being passed to a parameter of
6850 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6851 zero-based argument number. Do any required conversions. Return
6852 the converted value. */
6854 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
6856 push_defarg_context (tree fn
)
6857 { vec_safe_push (default_arg_context
, fn
); }
6860 pop_defarg_context (void)
6861 { default_arg_context
->pop (); }
6864 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
6865 tsubst_flags_t complain
)
6870 /* See through clones. */
6871 fn
= DECL_ORIGIN (fn
);
6873 /* Detect recursion. */
6874 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
6877 if (complain
& tf_error
)
6878 error ("recursive evaluation of default argument for %q#D", fn
);
6879 return error_mark_node
;
6882 /* If the ARG is an unparsed default argument expression, the
6883 conversion cannot be performed. */
6884 if (TREE_CODE (arg
) == DEFAULT_ARG
)
6886 if (complain
& tf_error
)
6887 error ("call to %qD uses the default argument for parameter %P, which "
6888 "is not yet defined", fn
, parmnum
);
6889 return error_mark_node
;
6892 push_defarg_context (fn
);
6894 if (fn
&& DECL_TEMPLATE_INFO (fn
))
6895 arg
= tsubst_default_argument (fn
, type
, arg
, complain
);
6901 The names in the expression are bound, and the semantic
6902 constraints are checked, at the point where the default
6903 expressions appears.
6905 we must not perform access checks here. */
6906 push_deferring_access_checks (dk_no_check
);
6907 /* We must make a copy of ARG, in case subsequent processing
6908 alters any part of it. */
6909 arg
= break_out_target_exprs (arg
);
6910 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
6911 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
6913 arg
= convert_for_arg_passing (type
, arg
, complain
);
6914 pop_deferring_access_checks();
6916 pop_defarg_context ();
6921 /* Returns the type which will really be used for passing an argument of
6925 type_passed_as (tree type
)
6927 /* Pass classes with copy ctors by invisible reference. */
6928 if (TREE_ADDRESSABLE (type
))
6930 type
= build_reference_type (type
);
6931 /* There are no other pointers to this temporary. */
6932 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
6934 else if (targetm
.calls
.promote_prototypes (type
)
6935 && INTEGRAL_TYPE_P (type
)
6936 && COMPLETE_TYPE_P (type
)
6937 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
6938 type
= integer_type_node
;
6943 /* Actually perform the appropriate conversion. */
6946 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
6950 /* If VAL is a bitfield, then -- since it has already been converted
6951 to TYPE -- it cannot have a precision greater than TYPE.
6953 If it has a smaller precision, we must widen it here. For
6954 example, passing "int f:3;" to a function expecting an "int" will
6955 not result in any conversion before this point.
6957 If the precision is the same we must not risk widening. For
6958 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6959 often have type "int", even though the C++ type for the field is
6960 "long long". If the value is being passed to a function
6961 expecting an "int", then no conversions will be required. But,
6962 if we call convert_bitfield_to_declared_type, the bitfield will
6963 be converted to "long long". */
6964 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
6966 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
6967 val
= convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type
), val
);
6969 if (val
== error_mark_node
)
6971 /* Pass classes with copy ctors by invisible reference. */
6972 else if (TREE_ADDRESSABLE (type
))
6973 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
6974 else if (targetm
.calls
.promote_prototypes (type
)
6975 && INTEGRAL_TYPE_P (type
)
6976 && COMPLETE_TYPE_P (type
)
6977 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
6978 val
= cp_perform_integral_promotions (val
, complain
);
6979 if ((complain
& tf_warning
)
6980 && warn_suggest_attribute_format
)
6982 tree rhstype
= TREE_TYPE (val
);
6983 const enum tree_code coder
= TREE_CODE (rhstype
);
6984 const enum tree_code codel
= TREE_CODE (type
);
6985 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
6987 && check_missing_format_attribute (type
, rhstype
))
6988 warning (OPT_Wsuggest_attribute_format
,
6989 "argument of function call might be a candidate for a format attribute");
6994 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6995 which no conversions at all should be done. This is true for some
6996 builtins which don't act like normal functions. */
6999 magic_varargs_p (tree fn
)
7001 if (flag_cilkplus
&& is_cilkplus_reduce_builtin (fn
) != BUILT_IN_NONE
)
7004 if (DECL_BUILT_IN (fn
))
7005 switch (DECL_FUNCTION_CODE (fn
))
7007 case BUILT_IN_CLASSIFY_TYPE
:
7008 case BUILT_IN_CONSTANT_P
:
7009 case BUILT_IN_NEXT_ARG
:
7010 case BUILT_IN_VA_START
:
7014 return lookup_attribute ("type generic",
7015 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7021 /* Returns the decl of the dispatcher function if FN is a function version. */
7024 get_function_version_dispatcher (tree fn
)
7026 tree dispatcher_decl
= NULL
;
7028 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7029 && DECL_FUNCTION_VERSIONED (fn
));
7031 gcc_assert (targetm
.get_function_versions_dispatcher
);
7032 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7034 if (dispatcher_decl
== NULL
)
7036 error_at (input_location
, "use of multiversioned function "
7037 "without a default");
7041 retrofit_lang_decl (dispatcher_decl
);
7042 gcc_assert (dispatcher_decl
!= NULL
);
7043 return dispatcher_decl
;
7046 /* fn is a function version dispatcher that is marked used. Mark all the
7047 semantically identical function versions it will dispatch as used. */
7050 mark_versions_used (tree fn
)
7052 struct cgraph_node
*node
;
7053 struct cgraph_function_version_info
*node_v
;
7054 struct cgraph_function_version_info
*it_v
;
7056 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7058 node
= cgraph_node::get (fn
);
7062 gcc_assert (node
->dispatcher_function
);
7064 node_v
= node
->function_version ();
7068 /* All semantically identical versions are chained. Traverse and mark each
7069 one of them as used. */
7070 it_v
= node_v
->next
;
7071 while (it_v
!= NULL
)
7073 mark_used (it_v
->this_node
->decl
);
7078 /* Build a call to "the copy constructor" for the type of A, even if it
7079 wouldn't be selected by normal overload resolution. Used for
7083 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7085 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7086 tree binfo
= TYPE_BINFO (ctype
);
7087 tree copy
= get_copy_ctor (ctype
, complain
);
7088 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7089 tree ob
= build_dummy_object (ctype
);
7090 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7091 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7092 LOOKUP_NORMAL
, NULL
, complain
);
7093 release_tree_vector (args
);
7097 /* Return true iff T refers to a base field. */
7100 is_base_field_ref (tree t
)
7103 if (TREE_CODE (t
) == ADDR_EXPR
)
7104 t
= TREE_OPERAND (t
, 0);
7105 if (TREE_CODE (t
) == COMPONENT_REF
)
7106 t
= TREE_OPERAND (t
, 1);
7107 if (TREE_CODE (t
) == FIELD_DECL
)
7108 return DECL_FIELD_IS_BASE (t
);
7112 /* We can't elide a copy from a function returning by value to a base
7113 subobject, as the callee might clobber tail padding. Return true iff this
7114 could be that case. */
7117 unsafe_copy_elision_p (tree target
, tree exp
)
7119 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7120 if (type
== CLASSTYPE_AS_BASE (type
))
7122 if (!is_base_field_ref (target
)
7123 && resolves_to_fixed_type_p (target
, NULL
))
7125 tree init
= TARGET_EXPR_INITIAL (exp
);
7126 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7127 && !AGGR_INIT_VIA_CTOR_P (init
));
7130 /* Subroutine of the various build_*_call functions. Overload resolution
7131 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7132 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7133 bitmask of various LOOKUP_* flags which apply to the call itself. */
7136 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7139 const vec
<tree
, va_gc
> *args
= cand
->args
;
7140 tree first_arg
= cand
->first_arg
;
7141 conversion
**convs
= cand
->convs
;
7143 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
7148 unsigned int arg_index
= 0;
7152 bool already_used
= false;
7154 /* In a template, there is no need to perform all of the work that
7155 is normally done. We are only interested in the type of the call
7156 expression, i.e., the return type of the function. Any semantic
7157 errors will be deferred until the template is instantiated. */
7158 if (processing_template_decl
)
7162 const tree
*argarray
;
7165 return_type
= TREE_TYPE (TREE_TYPE (fn
));
7166 nargs
= vec_safe_length (args
);
7167 if (first_arg
== NULL_TREE
)
7168 argarray
= args
->address ();
7176 alcarray
= XALLOCAVEC (tree
, nargs
);
7177 alcarray
[0] = build_this (first_arg
);
7178 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
7179 alcarray
[ix
+ 1] = arg
;
7180 argarray
= alcarray
;
7183 addr
= build_addr_func (fn
, complain
);
7184 if (addr
== error_mark_node
)
7185 return error_mark_node
;
7186 expr
= build_call_array_loc (input_location
, return_type
,
7187 addr
, nargs
, argarray
);
7188 if (TREE_THIS_VOLATILE (fn
) && cfun
)
7189 current_function_returns_abnormally
= 1;
7190 return convert_from_reference (expr
);
7193 /* Give any warnings we noticed during overload resolution. */
7194 if (cand
->warnings
&& (complain
& tf_warning
))
7196 struct candidate_warning
*w
;
7197 for (w
= cand
->warnings
; w
; w
= w
->next
)
7198 joust (cand
, w
->loser
, 1, complain
);
7201 /* Make =delete work with SFINAE. */
7202 if (DECL_DELETED_FN (fn
) && !(complain
& tf_error
))
7203 return error_mark_node
;
7205 if (DECL_FUNCTION_MEMBER_P (fn
))
7208 /* If FN is a template function, two cases must be considered.
7213 template <class T> void f();
7215 template <class T> struct B {
7219 struct C : A, B<int> {
7221 using B<int>::g; // #2
7224 In case #1 where `A::f' is a member template, DECL_ACCESS is
7225 recorded in the primary template but not in its specialization.
7226 We check access of FN using its primary template.
7228 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7229 because it is a member of class template B, DECL_ACCESS is
7230 recorded in the specialization `B<int>::g'. We cannot use its
7231 primary template because `B<T>::g' and `B<int>::g' may have
7232 different access. */
7233 if (DECL_TEMPLATE_INFO (fn
)
7234 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
7235 access_fn
= DECL_TI_TEMPLATE (fn
);
7238 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
7240 return error_mark_node
;
7243 /* If we're checking for implicit delete, don't bother with argument
7245 if (flags
& LOOKUP_SPECULATIVE
)
7247 if (DECL_DELETED_FN (fn
))
7249 if (complain
& tf_error
)
7251 return error_mark_node
;
7253 if (cand
->viable
== 1)
7255 else if (!(complain
& tf_error
))
7256 /* Reject bad conversions now. */
7257 return error_mark_node
;
7258 /* else continue to get conversion error. */
7261 /* N3276 magic doesn't apply to nested calls. */
7262 int decltype_flag
= (complain
& tf_decltype
);
7263 complain
&= ~tf_decltype
;
7265 /* Find maximum size of vector to hold converted arguments. */
7266 parmlen
= list_length (parm
);
7267 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
7268 if (parmlen
> nargs
)
7270 argarray
= XALLOCAVEC (tree
, nargs
);
7272 /* The implicit parameters to a constructor are not considered by overload
7273 resolution, and must be of the proper type. */
7274 if (DECL_CONSTRUCTOR_P (fn
))
7277 if (first_arg
!= NULL_TREE
)
7279 object_arg
= first_arg
;
7280 first_arg
= NULL_TREE
;
7284 object_arg
= (*args
)[arg_index
];
7287 argarray
[j
++] = build_this (object_arg
);
7288 parm
= TREE_CHAIN (parm
);
7289 /* We should never try to call the abstract constructor. */
7290 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
7292 if (DECL_HAS_VTT_PARM_P (fn
))
7294 argarray
[j
++] = (*args
)[arg_index
];
7296 parm
= TREE_CHAIN (parm
);
7299 /* Bypass access control for 'this' parameter. */
7300 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
7302 tree parmtype
= TREE_VALUE (parm
);
7303 tree arg
= build_this (first_arg
!= NULL_TREE
7305 : (*args
)[arg_index
]);
7306 tree argtype
= TREE_TYPE (arg
);
7310 if (convs
[i
]->bad_p
)
7312 if (complain
& tf_error
)
7314 if (permerror (input_location
, "passing %qT as %<this%> "
7315 "argument discards qualifiers",
7316 TREE_TYPE (argtype
)))
7317 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
7320 return error_mark_node
;
7323 /* See if the function member or the whole class type is declared
7324 final and the call can be devirtualized. */
7325 if (DECL_FINAL_P (fn
)
7326 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
7327 flags
|= LOOKUP_NONVIRTUAL
;
7329 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
7330 X is called for an object that is not of type X, or of a type
7331 derived from X, the behavior is undefined.
7333 So we can assume that anything passed as 'this' is non-null, and
7334 optimize accordingly. */
7335 gcc_assert (TYPE_PTR_P (parmtype
));
7336 /* Convert to the base in which the function was declared. */
7337 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
7338 converted_arg
= build_base_path (PLUS_EXPR
,
7340 cand
->conversion_path
,
7342 /* Check that the base class is accessible. */
7343 if (!accessible_base_p (TREE_TYPE (argtype
),
7344 BINFO_TYPE (cand
->conversion_path
), true))
7346 if (complain
& tf_error
)
7347 error ("%qT is not an accessible base of %qT",
7348 BINFO_TYPE (cand
->conversion_path
),
7349 TREE_TYPE (argtype
));
7351 return error_mark_node
;
7353 /* If fn was found by a using declaration, the conversion path
7354 will be to the derived class, not the base declaring fn. We
7355 must convert from derived to base. */
7356 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
7357 TREE_TYPE (parmtype
), ba_unique
,
7359 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
7360 base_binfo
, 1, complain
);
7362 argarray
[j
++] = converted_arg
;
7363 parm
= TREE_CHAIN (parm
);
7364 if (first_arg
!= NULL_TREE
)
7365 first_arg
= NULL_TREE
;
7372 gcc_assert (first_arg
== NULL_TREE
);
7373 for (; arg_index
< vec_safe_length (args
) && parm
;
7374 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
7376 tree type
= TREE_VALUE (parm
);
7377 tree arg
= (*args
)[arg_index
];
7378 bool conversion_warning
= true;
7382 /* If the argument is NULL and used to (implicitly) instantiate a
7383 template function (and bind one of the template arguments to
7384 the type of 'long int'), we don't want to warn about passing NULL
7385 to non-pointer argument.
7386 For example, if we have this template function:
7388 template<typename T> void func(T x) {}
7390 we want to warn (when -Wconversion is enabled) in this case:
7396 but not in this case:
7402 if (arg
== null_node
7403 && DECL_TEMPLATE_INFO (fn
)
7404 && cand
->template_decl
7405 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
7406 conversion_warning
= false;
7408 /* Warn about initializer_list deduction that isn't currently in the
7410 if (cxx_dialect
> cxx98
7411 && flag_deduce_init_list
7412 && cand
->template_decl
7413 && is_std_init_list (non_reference (type
))
7414 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
7416 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
7417 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
7418 tree patparm
= get_pattern_parm (realparm
, tmpl
);
7419 tree pattype
= TREE_TYPE (patparm
);
7420 if (PACK_EXPANSION_P (pattype
))
7421 pattype
= PACK_EXPANSION_PATTERN (pattype
);
7422 pattype
= non_reference (pattype
);
7424 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
7425 && (cand
->explicit_targs
== NULL_TREE
7426 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
7427 <= TEMPLATE_TYPE_IDX (pattype
))))
7429 pedwarn (input_location
, 0, "deducing %qT as %qT",
7430 non_reference (TREE_TYPE (patparm
)),
7431 non_reference (type
));
7432 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
7433 " in call to %qD", cand
->fn
);
7434 pedwarn (input_location
, 0,
7435 " (you can disable this with -fno-deduce-init-list)");
7438 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
7441 : complain
& (~tf_warning
));
7443 val
= convert_for_arg_passing (type
, val
, complain
);
7445 if (val
== error_mark_node
)
7446 return error_mark_node
;
7448 argarray
[j
++] = val
;
7451 /* Default arguments */
7452 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
7454 if (TREE_VALUE (parm
) == error_mark_node
)
7455 return error_mark_node
;
7456 argarray
[j
++] = convert_default_arg (TREE_VALUE (parm
),
7457 TREE_PURPOSE (parm
),
7463 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
7465 tree a
= (*args
)[arg_index
];
7466 if (magic_varargs_p (fn
))
7467 /* Do no conversions for magic varargs. */
7468 a
= mark_type_use (a
);
7469 else if (DECL_CONSTRUCTOR_P (fn
)
7470 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
7473 /* Avoid infinite recursion trying to call A(...). */
7474 if (complain
& tf_error
)
7475 /* Try to call the actual copy constructor for a good error. */
7476 call_copy_ctor (a
, complain
);
7477 return error_mark_node
;
7480 a
= convert_arg_to_ellipsis (a
, complain
);
7484 gcc_assert (j
<= nargs
);
7487 check_function_arguments (TREE_TYPE (fn
), nargs
, argarray
);
7489 /* Avoid actually calling copy constructors and copy assignment operators,
7492 if (! flag_elide_constructors
)
7493 /* Do things the hard way. */;
7494 else if (cand
->num_convs
== 1
7495 && (DECL_COPY_CONSTRUCTOR_P (fn
)
7496 || DECL_MOVE_CONSTRUCTOR_P (fn
))
7497 /* It's unsafe to elide the constructor when handling
7498 a noexcept-expression, it may evaluate to the wrong
7499 value (c++/53025). */
7500 && cp_noexcept_operand
== 0)
7503 tree arg
= argarray
[num_artificial_parms_for (fn
)];
7505 bool trivial
= trivial_fn_p (fn
);
7507 /* Pull out the real argument, disregarding const-correctness. */
7509 while (CONVERT_EXPR_P (targ
)
7510 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
7511 targ
= TREE_OPERAND (targ
, 0);
7512 if (TREE_CODE (targ
) == ADDR_EXPR
)
7514 targ
= TREE_OPERAND (targ
, 0);
7515 if (!same_type_ignoring_top_level_qualifiers_p
7516 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
7525 arg
= cp_build_indirect_ref (arg
, RO_NULL
, complain
);
7527 /* [class.copy]: the copy constructor is implicitly defined even if
7528 the implementation elided its use. */
7529 if (!trivial
|| DECL_DELETED_FN (fn
))
7531 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
7532 return error_mark_node
;
7533 already_used
= true;
7536 /* If we're creating a temp and we already have one, don't create a
7537 new one. If we're not creating a temp but we get one, use
7538 INIT_EXPR to collapse the temp into our target. Otherwise, if the
7539 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
7540 temp or an INIT_EXPR otherwise. */
7542 if (is_dummy_object (fa
))
7544 if (TREE_CODE (arg
) == TARGET_EXPR
)
7547 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
7550 || (TREE_CODE (arg
) == TARGET_EXPR
7551 && !unsafe_copy_elision_p (fa
, arg
)))
7553 tree to
= stabilize_reference (cp_build_indirect_ref (fa
, RO_NULL
,
7556 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
7560 else if (DECL_OVERLOADED_OPERATOR_P (fn
) == NOP_EXPR
7561 && trivial_fn_p (fn
)
7562 && !DECL_DELETED_FN (fn
))
7564 tree to
= stabilize_reference
7565 (cp_build_indirect_ref (argarray
[0], RO_NULL
, complain
));
7566 tree type
= TREE_TYPE (to
);
7567 tree as_base
= CLASSTYPE_AS_BASE (type
);
7568 tree arg
= argarray
[1];
7570 if (is_really_empty_class (type
))
7572 /* Avoid copying empty classes. */
7573 val
= build2 (COMPOUND_EXPR
, void_type_node
, to
, arg
);
7574 TREE_NO_WARNING (val
) = 1;
7575 val
= build2 (COMPOUND_EXPR
, type
, val
, to
);
7576 TREE_NO_WARNING (val
) = 1;
7578 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
7580 arg
= cp_build_indirect_ref (arg
, RO_NULL
, complain
);
7581 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
7585 /* We must only copy the non-tail padding parts. */
7587 tree array_type
, alias_set
;
7589 arg2
= TYPE_SIZE_UNIT (as_base
);
7590 arg0
= cp_build_addr_expr (to
, complain
);
7592 array_type
= build_array_type (char_type_node
,
7594 (size_binop (MINUS_EXPR
,
7595 arg2
, size_int (1))));
7596 alias_set
= build_int_cst (build_pointer_type (type
), 0);
7597 t
= build2 (MODIFY_EXPR
, void_type_node
,
7598 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
7599 build2 (MEM_REF
, array_type
, arg
, alias_set
));
7600 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
7601 TREE_NO_WARNING (val
) = 1;
7606 else if (DECL_DESTRUCTOR_P (fn
)
7607 && trivial_fn_p (fn
)
7608 && !DECL_DELETED_FN (fn
))
7609 return fold_convert (void_type_node
, argarray
[0]);
7610 /* FIXME handle trivial default constructor, too. */
7612 /* For calls to a multi-versioned function, overload resolution
7613 returns the function with the highest target priority, that is,
7614 the version that will checked for dispatching first. If this
7615 version is inlinable, a direct call to this version can be made
7616 otherwise the call should go through the dispatcher. */
7618 if (DECL_FUNCTION_VERSIONED (fn
)
7619 && (current_function_decl
== NULL
7620 || !targetm
.target_option
.can_inline_p (current_function_decl
, fn
)))
7622 fn
= get_function_version_dispatcher (fn
);
7626 mark_versions_used (fn
);
7630 && !mark_used (fn
, complain
))
7631 return error_mark_node
;
7633 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0
7634 /* Don't mess with virtual lookup in instantiate_non_dependent_expr;
7635 virtual functions can't be constexpr. */
7636 && !in_template_function ())
7639 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
7641 ba_any
, NULL
, complain
);
7642 gcc_assert (binfo
&& binfo
!= error_mark_node
);
7644 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
7646 if (TREE_SIDE_EFFECTS (argarray
[0]))
7647 argarray
[0] = save_expr (argarray
[0]);
7648 t
= build_pointer_type (TREE_TYPE (fn
));
7649 if (DECL_CONTEXT (fn
) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn
)))
7650 fn
= build_java_interface_fn_ref (fn
, argarray
[0]);
7652 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
7657 fn
= build_addr_func (fn
, complain
);
7658 if (fn
== error_mark_node
)
7659 return error_mark_node
;
7662 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
7663 if (TREE_CODE (call
) == CALL_EXPR
7664 && (cand
->flags
& LOOKUP_LIST_INIT_CTOR
))
7665 CALL_EXPR_LIST_INIT_P (call
) = true;
7669 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
7670 This function performs no overload resolution, conversion, or other
7671 high-level operations. */
7674 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
7675 tsubst_flags_t complain
)
7680 /* Remember roughly where this call is. */
7681 location_t loc
= EXPR_LOC_OR_LOC (fn
, input_location
);
7682 fn
= build_call_a (fn
, nargs
, argarray
);
7683 SET_EXPR_LOCATION (fn
, loc
);
7685 fndecl
= get_callee_fndecl (fn
);
7687 /* Check that arguments to builtin functions match the expectations. */
7689 && DECL_BUILT_IN (fndecl
)
7690 && DECL_BUILT_IN_CLASS (fndecl
) == BUILT_IN_NORMAL
7691 && !check_builtin_function_arguments (fndecl
, nargs
, argarray
))
7692 return error_mark_node
;
7694 /* If it is a built-in array notation function, then the return type of
7695 the function is the element type of the array passed in as array
7696 notation (i.e. the first parameter of the function). */
7697 if (flag_cilkplus
&& TREE_CODE (fn
) == CALL_EXPR
)
7699 enum built_in_function bif
=
7700 is_cilkplus_reduce_builtin (CALL_EXPR_FN (fn
));
7701 if (bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_ADD
7702 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MUL
7703 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MAX
7704 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MIN
7705 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE
7706 || bif
== BUILT_IN_CILKPLUS_SEC_REDUCE_MUTATING
)
7708 if (call_expr_nargs (fn
) == 0)
7710 error_at (EXPR_LOCATION (fn
), "Invalid builtin arguments");
7711 return error_mark_node
;
7713 /* for bif == BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_ZERO or
7714 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_ZERO or
7715 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_NONZERO or
7716 BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_NONZERO or
7717 BUILT_IN_CILKPLUS_SEC_REDUCE_MIN_IND or
7718 BUILT_IN_CILKPLUS_SEC_REDUCE_MAX_IND
7719 The pre-defined return-type is the correct one. */
7720 tree array_ntn
= CALL_EXPR_ARG (fn
, 0);
7721 TREE_TYPE (fn
) = TREE_TYPE (array_ntn
);
7726 /* Some built-in function calls will be evaluated at compile-time in
7727 fold (). Set optimize to 1 when folding __builtin_constant_p inside
7728 a constexpr function so that fold_builtin_1 doesn't fold it to 0. */
7729 optimize_sav
= optimize
;
7730 if (!optimize
&& fndecl
&& DECL_IS_BUILTIN_CONSTANT_P (fndecl
)
7731 && current_function_decl
7732 && DECL_DECLARED_CONSTEXPR_P (current_function_decl
))
7734 fn
= fold_if_not_in_template (fn
);
7735 optimize
= optimize_sav
;
7737 if (VOID_TYPE_P (TREE_TYPE (fn
)))
7740 /* 5.2.2/11: If a function call is a prvalue of object type: if the
7741 function call is either the operand of a decltype-specifier or the
7742 right operand of a comma operator that is the operand of a
7743 decltype-specifier, a temporary object is not introduced for the
7744 prvalue. The type of the prvalue may be incomplete. */
7745 if (!(complain
& tf_decltype
))
7747 fn
= require_complete_type_sfinae (fn
, complain
);
7748 if (fn
== error_mark_node
)
7749 return error_mark_node
;
7751 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
7752 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
7754 return convert_from_reference (fn
);
7757 static GTY(()) tree java_iface_lookup_fn
;
7759 /* Make an expression which yields the address of the Java interface
7760 method FN. This is achieved by generating a call to libjava's
7761 _Jv_LookupInterfaceMethodIdx(). */
7764 build_java_interface_fn_ref (tree fn
, tree instance
)
7766 tree lookup_fn
, method
, idx
;
7767 tree klass_ref
, iface
, iface_ref
;
7770 if (!java_iface_lookup_fn
)
7772 tree ftype
= build_function_type_list (ptr_type_node
,
7773 ptr_type_node
, ptr_type_node
,
7774 java_int_type_node
, NULL_TREE
);
7775 java_iface_lookup_fn
7776 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype
,
7777 0, NOT_BUILT_IN
, NULL
, NULL_TREE
);
7780 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
7781 This is the first entry in the vtable. */
7782 klass_ref
= build_vtbl_ref (cp_build_indirect_ref (instance
, RO_NULL
,
7783 tf_warning_or_error
),
7786 /* Get the java.lang.Class pointer for the interface being called. */
7787 iface
= DECL_CONTEXT (fn
);
7788 iface_ref
= lookup_field (iface
, get_identifier ("class$"), 0, false);
7789 if (!iface_ref
|| !VAR_P (iface_ref
)
7790 || DECL_CONTEXT (iface_ref
) != iface
)
7792 error ("could not find class$ field in java interface type %qT",
7794 return error_mark_node
;
7796 iface_ref
= build_address (iface_ref
);
7797 iface_ref
= convert (build_pointer_type (iface
), iface_ref
);
7799 /* Determine the itable index of FN. */
7801 for (method
= TYPE_METHODS (iface
); method
; method
= DECL_CHAIN (method
))
7803 if (!DECL_VIRTUAL_P (method
))
7809 idx
= build_int_cst (NULL_TREE
, i
);
7811 lookup_fn
= build1 (ADDR_EXPR
,
7812 build_pointer_type (TREE_TYPE (java_iface_lookup_fn
)),
7813 java_iface_lookup_fn
);
7814 return build_call_nary (ptr_type_node
, lookup_fn
,
7815 3, klass_ref
, iface_ref
, idx
);
7818 /* Returns the value to use for the in-charge parameter when making a
7819 call to a function with the indicated NAME.
7821 FIXME:Can't we find a neater way to do this mapping? */
7824 in_charge_arg_for_name (tree name
)
7826 if (name
== base_ctor_identifier
7827 || name
== base_dtor_identifier
)
7828 return integer_zero_node
;
7829 else if (name
== complete_ctor_identifier
)
7830 return integer_one_node
;
7831 else if (name
== complete_dtor_identifier
)
7832 return integer_two_node
;
7833 else if (name
== deleting_dtor_identifier
)
7834 return integer_three_node
;
7836 /* This function should only be called with one of the names listed
7842 /* Build a call to a constructor, destructor, or an assignment
7843 operator for INSTANCE, an expression with class type. NAME
7844 indicates the special member function to call; *ARGS are the
7845 arguments. ARGS may be NULL. This may change ARGS. BINFO
7846 indicates the base of INSTANCE that is to be passed as the `this'
7847 parameter to the member function called.
7849 FLAGS are the LOOKUP_* flags to use when processing the call.
7851 If NAME indicates a complete object constructor, INSTANCE may be
7852 NULL_TREE. In this case, the caller will call build_cplus_new to
7853 store the newly constructed object into a VAR_DECL. */
7856 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
7857 tree binfo
, int flags
, tsubst_flags_t complain
)
7860 /* The type of the subobject to be constructed or destroyed. */
7862 vec
<tree
, va_gc
> *allocated
= NULL
;
7865 gcc_assert (name
== complete_ctor_identifier
7866 || name
== base_ctor_identifier
7867 || name
== complete_dtor_identifier
7868 || name
== base_dtor_identifier
7869 || name
== deleting_dtor_identifier
7870 || name
== ansi_assopname (NOP_EXPR
));
7873 /* Resolve the name. */
7874 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
7875 return error_mark_node
;
7877 binfo
= TYPE_BINFO (binfo
);
7880 gcc_assert (binfo
!= NULL_TREE
);
7882 class_type
= BINFO_TYPE (binfo
);
7884 /* Handle the special case where INSTANCE is NULL_TREE. */
7885 if (name
== complete_ctor_identifier
&& !instance
)
7886 instance
= build_dummy_object (class_type
);
7889 if (name
== complete_dtor_identifier
7890 || name
== base_dtor_identifier
7891 || name
== deleting_dtor_identifier
)
7892 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
7894 /* Convert to the base class, if necessary. */
7895 if (!same_type_ignoring_top_level_qualifiers_p
7896 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
7898 if (name
!= ansi_assopname (NOP_EXPR
))
7899 /* For constructors and destructors, either the base is
7900 non-virtual, or it is virtual but we are doing the
7901 conversion from a constructor or destructor for the
7902 complete object. In either case, we can convert
7904 instance
= convert_to_base_statically (instance
, binfo
);
7906 /* However, for assignment operators, we must convert
7907 dynamically if the base is virtual. */
7908 instance
= build_base_path (PLUS_EXPR
, instance
,
7909 binfo
, /*nonnull=*/1, complain
);
7913 gcc_assert (instance
!= NULL_TREE
);
7915 fns
= lookup_fnfields (binfo
, name
, 1);
7917 /* When making a call to a constructor or destructor for a subobject
7918 that uses virtual base classes, pass down a pointer to a VTT for
7920 if ((name
== base_ctor_identifier
7921 || name
== base_dtor_identifier
)
7922 && CLASSTYPE_VBASECLASSES (class_type
))
7927 /* If the current function is a complete object constructor
7928 or destructor, then we fetch the VTT directly.
7929 Otherwise, we look it up using the VTT we were given. */
7930 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
7931 vtt
= decay_conversion (vtt
, complain
);
7932 if (vtt
== error_mark_node
)
7933 return error_mark_node
;
7934 vtt
= build3 (COND_EXPR
, TREE_TYPE (vtt
),
7935 build2 (EQ_EXPR
, boolean_type_node
,
7936 current_in_charge_parm
, integer_zero_node
),
7939 if (BINFO_SUBVTT_INDEX (binfo
))
7940 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
7946 allocated
= make_tree_vector ();
7950 vec_safe_insert (*args
, 0, sub_vtt
);
7953 ret
= build_new_method_call (instance
, fns
, args
,
7954 TYPE_BINFO (BINFO_TYPE (binfo
)),
7958 if (allocated
!= NULL
)
7959 release_tree_vector (allocated
);
7961 if ((complain
& tf_error
)
7962 && (flags
& LOOKUP_DELEGATING_CONS
)
7963 && name
== complete_ctor_identifier
7964 && TREE_CODE (ret
) == CALL_EXPR
7965 && (DECL_ABSTRACT_ORIGIN (TREE_OPERAND (CALL_EXPR_FN (ret
), 0))
7966 == current_function_decl
))
7967 error ("constructor delegates to itself");
7972 /* Return the NAME, as a C string. The NAME indicates a function that
7973 is a member of TYPE. *FREE_P is set to true if the caller must
7974 free the memory returned.
7976 Rather than go through all of this, we should simply set the names
7977 of constructors and destructors appropriately, and dispense with
7978 ctor_identifier, dtor_identifier, etc. */
7981 name_as_c_string (tree name
, tree type
, bool *free_p
)
7985 /* Assume that we will not allocate memory. */
7987 /* Constructors and destructors are special. */
7988 if (IDENTIFIER_CTOR_OR_DTOR_P (name
))
7991 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
))));
7992 /* For a destructor, add the '~'. */
7993 if (name
== complete_dtor_identifier
7994 || name
== base_dtor_identifier
7995 || name
== deleting_dtor_identifier
)
7997 pretty_name
= concat ("~", pretty_name
, NULL
);
7998 /* Remember that we need to free the memory allocated. */
8002 else if (IDENTIFIER_TYPENAME_P (name
))
8004 pretty_name
= concat ("operator ",
8005 type_as_string_translate (TREE_TYPE (name
),
8006 TFF_PLAIN_IDENTIFIER
),
8008 /* Remember that we need to free the memory allocated. */
8012 pretty_name
= CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name
)));
8017 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
8018 be set, upon return, to the function called. ARGS may be NULL.
8019 This may change ARGS. */
8022 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
8023 tree conversion_path
, int flags
,
8024 tree
*fn_p
, tsubst_flags_t complain
)
8026 struct z_candidate
*candidates
= 0, *cand
;
8027 tree explicit_targs
= NULL_TREE
;
8028 tree basetype
= NULL_TREE
;
8029 tree access_binfo
, binfo
;
8031 tree first_mem_arg
= NULL_TREE
;
8033 bool skip_first_for_error
;
8034 vec
<tree
, va_gc
> *user_args
;
8037 int template_only
= 0;
8041 vec
<tree
, va_gc
> *orig_args
= NULL
;
8044 gcc_assert (instance
!= NULL_TREE
);
8046 /* We don't know what function we're going to call, yet. */
8050 if (error_operand_p (instance
)
8051 || !fns
|| error_operand_p (fns
))
8052 return error_mark_node
;
8054 if (!BASELINK_P (fns
))
8056 if (complain
& tf_error
)
8057 error ("call to non-function %qD", fns
);
8058 return error_mark_node
;
8061 orig_instance
= instance
;
8064 /* Dismantle the baselink to collect all the information we need. */
8065 if (!conversion_path
)
8066 conversion_path
= BASELINK_BINFO (fns
);
8067 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
8068 binfo
= BASELINK_BINFO (fns
);
8069 optype
= BASELINK_OPTYPE (fns
);
8070 fns
= BASELINK_FUNCTIONS (fns
);
8071 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
8073 explicit_targs
= TREE_OPERAND (fns
, 1);
8074 fns
= TREE_OPERAND (fns
, 0);
8077 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
8078 || TREE_CODE (fns
) == TEMPLATE_DECL
8079 || TREE_CODE (fns
) == OVERLOAD
);
8080 fn
= get_first_fn (fns
);
8081 name
= DECL_NAME (fn
);
8083 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
8084 gcc_assert (CLASS_TYPE_P (basetype
));
8086 if (processing_template_decl
)
8088 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
8089 instance
= build_non_dependent_expr (instance
);
8091 make_args_non_dependent (*args
);
8094 user_args
= args
== NULL
? NULL
: *args
;
8095 /* Under DR 147 A::A() is an invalid constructor call,
8096 not a functional cast. */
8097 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
8099 if (! (complain
& tf_error
))
8100 return error_mark_node
;
8102 if (permerror (input_location
,
8103 "cannot call constructor %<%T::%D%> directly",
8105 inform (input_location
, "for a function-style cast, remove the "
8106 "redundant %<::%D%>", name
);
8107 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
8112 /* Figure out whether to skip the first argument for the error
8113 message we will display to users if an error occurs. We don't
8114 want to display any compiler-generated arguments. The "this"
8115 pointer hasn't been added yet. However, we must remove the VTT
8116 pointer if this is a call to a base-class constructor or
8118 skip_first_for_error
= false;
8119 if (IDENTIFIER_CTOR_OR_DTOR_P (name
))
8121 /* Callers should explicitly indicate whether they want to construct
8122 the complete object or just the part without virtual bases. */
8123 gcc_assert (name
!= ctor_identifier
);
8124 /* Similarly for destructors. */
8125 gcc_assert (name
!= dtor_identifier
);
8126 /* Remove the VTT pointer, if present. */
8127 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
8128 && CLASSTYPE_VBASECLASSES (basetype
))
8129 skip_first_for_error
= true;
8132 /* Process the argument list. */
8133 if (args
!= NULL
&& *args
!= NULL
)
8135 *args
= resolve_args (*args
, complain
);
8137 return error_mark_node
;
8140 /* Consider the object argument to be used even if we end up selecting a
8141 static member function. */
8142 instance
= mark_type_use (instance
);
8144 /* It's OK to call destructors and constructors on cv-qualified objects.
8145 Therefore, convert the INSTANCE to the unqualified type, if
8147 if (DECL_DESTRUCTOR_P (fn
)
8148 || DECL_CONSTRUCTOR_P (fn
))
8150 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
8152 instance
= build_this (instance
);
8153 instance
= build_nop (build_pointer_type (basetype
), instance
);
8154 instance
= build_fold_indirect_ref (instance
);
8157 if (DECL_DESTRUCTOR_P (fn
))
8158 name
= complete_dtor_identifier
;
8160 /* For the overload resolution we need to find the actual `this`
8161 that would be captured if the call turns out to be to a
8162 non-static member function. Do not actually capture it at this
8164 if (DECL_CONSTRUCTOR_P (fn
))
8165 /* Constructors don't use the enclosing 'this'. */
8166 first_mem_arg
= instance
;
8168 first_mem_arg
= maybe_resolve_dummy (instance
, false);
8170 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8171 p
= conversion_obstack_alloc (0);
8173 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
8174 initializer, not T({ }). */
8175 if (DECL_CONSTRUCTOR_P (fn
) && args
!= NULL
&& !vec_safe_is_empty (*args
)
8176 && DIRECT_LIST_INIT_P ((**args
)[0]))
8178 tree init_list
= (**args
)[0];
8179 tree init
= NULL_TREE
;
8181 gcc_assert ((*args
)->length () == 1
8182 && !(flags
& LOOKUP_ONLYCONVERTING
));
8184 /* If the initializer list has no elements and T is a class type with
8185 a default constructor, the object is value-initialized. Handle
8186 this here so we don't need to handle it wherever we use
8187 build_special_member_call. */
8188 if (CONSTRUCTOR_NELTS (init_list
) == 0
8189 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
8190 /* For a user-provided default constructor, use the normal
8191 mechanisms so that protected access works. */
8192 && type_has_non_user_provided_default_constructor (basetype
)
8193 && !processing_template_decl
)
8194 init
= build_value_init (basetype
, complain
);
8196 /* If BASETYPE is an aggregate, we need to do aggregate
8198 else if (CP_AGGREGATE_TYPE_P (basetype
))
8200 init
= reshape_init (basetype
, init_list
, complain
);
8201 init
= digest_init (basetype
, init
, complain
);
8206 if (is_dummy_object (instance
))
8207 return get_target_expr_sfinae (init
, complain
);
8208 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
8209 TREE_SIDE_EFFECTS (init
) = true;
8213 /* Otherwise go ahead with overload resolution. */
8214 add_list_candidates (fns
, first_mem_arg
, init_list
,
8215 basetype
, explicit_targs
, template_only
,
8216 conversion_path
, access_binfo
, flags
,
8217 &candidates
, complain
);
8221 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
8222 explicit_targs
, template_only
, conversion_path
,
8223 access_binfo
, flags
, &candidates
, complain
);
8225 any_viable_p
= false;
8226 candidates
= splice_viable (candidates
, false, &any_viable_p
);
8230 if (complain
& tf_error
)
8232 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
8233 cxx_incomplete_type_error (instance
, basetype
);
8235 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
8236 basetype
, optype
, build_tree_list_vec (user_args
),
8237 TREE_TYPE (instance
));
8244 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
8245 arglist
= build_tree_list_vec (user_args
);
8246 if (skip_first_for_error
)
8247 arglist
= TREE_CHAIN (arglist
);
8248 error ("no matching function for call to %<%T::%s(%A)%#V%>",
8249 basetype
, pretty_name
, arglist
,
8250 TREE_TYPE (instance
));
8254 print_z_candidates (location_of (name
), candidates
);
8256 call
= error_mark_node
;
8260 cand
= tourney (candidates
, complain
);
8267 if (complain
& tf_error
)
8269 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
8270 arglist
= build_tree_list_vec (user_args
);
8271 if (skip_first_for_error
)
8272 arglist
= TREE_CHAIN (arglist
);
8273 if (!any_strictly_viable (candidates
))
8274 error ("no matching function for call to %<%s(%A)%>",
8275 pretty_name
, arglist
);
8277 error ("call of overloaded %<%s(%A)%> is ambiguous",
8278 pretty_name
, arglist
);
8279 print_z_candidates (location_of (name
), candidates
);
8283 call
= error_mark_node
;
8290 if (!(flags
& LOOKUP_NONVIRTUAL
)
8291 && DECL_PURE_VIRTUAL_P (fn
)
8292 && instance
== current_class_ref
8293 && (complain
& tf_warning
))
8295 /* This is not an error, it is runtime undefined
8297 if (!current_function_decl
)
8298 warning (0, "pure virtual %q#D called from "
8299 "non-static data member initializer", fn
);
8300 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
8301 || DECL_DESTRUCTOR_P (current_function_decl
))
8302 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
8303 ? "pure virtual %q#D called from constructor"
8304 : "pure virtual %q#D called from destructor"),
8308 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
8309 && !DECL_CONSTRUCTOR_P (fn
)
8310 && is_dummy_object (instance
))
8312 instance
= maybe_resolve_dummy (instance
, true);
8313 if (instance
== error_mark_node
)
8314 call
= error_mark_node
;
8315 else if (!is_dummy_object (instance
))
8317 /* We captured 'this' in the current lambda now that
8318 we know we really need it. */
8319 cand
->first_arg
= instance
;
8323 if (complain
& tf_error
)
8324 error ("cannot call member function %qD without object",
8326 call
= error_mark_node
;
8330 if (call
!= error_mark_node
)
8332 /* Optimize away vtable lookup if we know that this
8333 function can't be overridden. We need to check if
8334 the context and the type where we found fn are the same,
8335 actually FN might be defined in a different class
8336 type because of a using-declaration. In this case, we
8337 do not want to perform a non-virtual call. */
8338 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
8339 && same_type_ignoring_top_level_qualifiers_p
8340 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
8341 && resolves_to_fixed_type_p (instance
, 0))
8342 flags
|= LOOKUP_NONVIRTUAL
;
8344 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
8345 /* Now we know what function is being called. */
8348 /* Build the actual CALL_EXPR. */
8349 call
= build_over_call (cand
, flags
, complain
);
8350 /* In an expression of the form `a->f()' where `f' turns
8351 out to be a static member function, `a' is
8352 none-the-less evaluated. */
8353 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
8354 && !is_dummy_object (instance
)
8355 && TREE_SIDE_EFFECTS (instance
))
8356 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
),
8358 else if (call
!= error_mark_node
8359 && DECL_DESTRUCTOR_P (cand
->fn
)
8360 && !VOID_TYPE_P (TREE_TYPE (call
)))
8361 /* An explicit call of the form "x->~X()" has type
8362 "void". However, on platforms where destructors
8363 return "this" (i.e., those where
8364 targetm.cxx.cdtor_returns_this is true), such calls
8365 will appear to have a return value of pointer type
8366 to the low-level call machinery. We do not want to
8367 change the low-level machinery, since we want to be
8368 able to optimize "delete f()" on such platforms as
8369 "operator delete(~X(f()))" (rather than generating
8370 "t = f(), ~X(t), operator delete (t)"). */
8371 call
= build_nop (void_type_node
, call
);
8376 if (processing_template_decl
&& call
!= error_mark_node
)
8378 bool cast_to_void
= false;
8380 if (TREE_CODE (call
) == COMPOUND_EXPR
)
8381 call
= TREE_OPERAND (call
, 1);
8382 else if (TREE_CODE (call
) == NOP_EXPR
)
8384 cast_to_void
= true;
8385 call
= TREE_OPERAND (call
, 0);
8387 if (INDIRECT_REF_P (call
))
8388 call
= TREE_OPERAND (call
, 0);
8389 call
= (build_min_non_dep_call_vec
8391 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
8392 orig_instance
, orig_fns
, NULL_TREE
),
8394 SET_EXPR_LOCATION (call
, input_location
);
8395 call
= convert_from_reference (call
);
8397 call
= build_nop (void_type_node
, call
);
8400 /* Free all the conversions we allocated. */
8401 obstack_free (&conversion_obstack
, p
);
8403 if (orig_args
!= NULL
)
8404 release_tree_vector (orig_args
);
8409 /* Wrapper for above. */
8412 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
8413 tree conversion_path
, int flags
,
8414 tree
*fn_p
, tsubst_flags_t complain
)
8417 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
8418 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
8420 timevar_cond_stop (TV_OVERLOAD
, subtime
);
8424 /* Returns true iff standard conversion sequence ICS1 is a proper
8425 subsequence of ICS2. */
8428 is_subseq (conversion
*ics1
, conversion
*ics2
)
8430 /* We can assume that a conversion of the same code
8431 between the same types indicates a subsequence since we only get
8432 here if the types we are converting from are the same. */
8434 while (ics1
->kind
== ck_rvalue
8435 || ics1
->kind
== ck_lvalue
)
8436 ics1
= next_conversion (ics1
);
8440 while (ics2
->kind
== ck_rvalue
8441 || ics2
->kind
== ck_lvalue
)
8442 ics2
= next_conversion (ics2
);
8444 if (ics2
->kind
== ck_user
8445 || ics2
->kind
== ck_ambig
8446 || ics2
->kind
== ck_aggr
8447 || ics2
->kind
== ck_list
8448 || ics2
->kind
== ck_identity
)
8449 /* At this point, ICS1 cannot be a proper subsequence of
8450 ICS2. We can get a USER_CONV when we are comparing the
8451 second standard conversion sequence of two user conversion
8455 ics2
= next_conversion (ics2
);
8457 if (ics2
->kind
== ics1
->kind
8458 && same_type_p (ics2
->type
, ics1
->type
)
8459 && same_type_p (next_conversion (ics2
)->type
,
8460 next_conversion (ics1
)->type
))
8465 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
8466 be any _TYPE nodes. */
8469 is_properly_derived_from (tree derived
, tree base
)
8471 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
8474 /* We only allow proper derivation here. The DERIVED_FROM_P macro
8475 considers every class derived from itself. */
8476 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
8477 && DERIVED_FROM_P (base
, derived
));
8480 /* We build the ICS for an implicit object parameter as a pointer
8481 conversion sequence. However, such a sequence should be compared
8482 as if it were a reference conversion sequence. If ICS is the
8483 implicit conversion sequence for an implicit object parameter,
8484 modify it accordingly. */
8487 maybe_handle_implicit_object (conversion
**ics
)
8491 /* [over.match.funcs]
8493 For non-static member functions, the type of the
8494 implicit object parameter is "reference to cv X"
8495 where X is the class of which the function is a
8496 member and cv is the cv-qualification on the member
8497 function declaration. */
8498 conversion
*t
= *ics
;
8499 tree reference_type
;
8501 /* The `this' parameter is a pointer to a class type. Make the
8502 implicit conversion talk about a reference to that same class
8504 reference_type
= TREE_TYPE (t
->type
);
8505 reference_type
= build_reference_type (reference_type
);
8507 if (t
->kind
== ck_qual
)
8508 t
= next_conversion (t
);
8509 if (t
->kind
== ck_ptr
)
8510 t
= next_conversion (t
);
8511 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
8512 t
= direct_reference_binding (reference_type
, t
);
8514 t
->rvaluedness_matches_p
= 0;
8519 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
8520 and return the initial reference binding conversion. Otherwise,
8521 leave *ICS unchanged and return NULL. */
8524 maybe_handle_ref_bind (conversion
**ics
)
8526 if ((*ics
)->kind
== ck_ref_bind
)
8528 conversion
*old_ics
= *ics
;
8529 *ics
= next_conversion (old_ics
);
8530 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
8537 /* Compare two implicit conversion sequences according to the rules set out in
8538 [over.ics.rank]. Return values:
8540 1: ics1 is better than ics2
8541 -1: ics2 is better than ics1
8542 0: ics1 and ics2 are indistinguishable */
8545 compare_ics (conversion
*ics1
, conversion
*ics2
)
8551 tree deref_from_type1
= NULL_TREE
;
8552 tree deref_from_type2
= NULL_TREE
;
8553 tree deref_to_type1
= NULL_TREE
;
8554 tree deref_to_type2
= NULL_TREE
;
8555 conversion_rank rank1
, rank2
;
8557 /* REF_BINDING is nonzero if the result of the conversion sequence
8558 is a reference type. In that case REF_CONV is the reference
8559 binding conversion. */
8560 conversion
*ref_conv1
;
8561 conversion
*ref_conv2
;
8563 /* Compare badness before stripping the reference conversion. */
8564 if (ics1
->bad_p
> ics2
->bad_p
)
8566 else if (ics1
->bad_p
< ics2
->bad_p
)
8569 /* Handle implicit object parameters. */
8570 maybe_handle_implicit_object (&ics1
);
8571 maybe_handle_implicit_object (&ics2
);
8573 /* Handle reference parameters. */
8574 ref_conv1
= maybe_handle_ref_bind (&ics1
);
8575 ref_conv2
= maybe_handle_ref_bind (&ics2
);
8577 /* List-initialization sequence L1 is a better conversion sequence than
8578 list-initialization sequence L2 if L1 converts to
8579 std::initializer_list<X> for some X and L2 does not. */
8580 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
8582 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
8587 When comparing the basic forms of implicit conversion sequences (as
8588 defined in _over.best.ics_)
8590 --a standard conversion sequence (_over.ics.scs_) is a better
8591 conversion sequence than a user-defined conversion sequence
8592 or an ellipsis conversion sequence, and
8594 --a user-defined conversion sequence (_over.ics.user_) is a
8595 better conversion sequence than an ellipsis conversion sequence
8596 (_over.ics.ellipsis_). */
8597 /* Use BAD_CONVERSION_RANK because we already checked for a badness
8598 mismatch. If both ICS are bad, we try to make a decision based on
8599 what would have happened if they'd been good. This is not an
8600 extension, we'll still give an error when we build up the call; this
8601 just helps us give a more helpful error message. */
8602 rank1
= BAD_CONVERSION_RANK (ics1
);
8603 rank2
= BAD_CONVERSION_RANK (ics2
);
8607 else if (rank1
< rank2
)
8610 if (ics1
->ellipsis_p
)
8611 /* Both conversions are ellipsis conversions. */
8614 /* User-defined conversion sequence U1 is a better conversion sequence
8615 than another user-defined conversion sequence U2 if they contain the
8616 same user-defined conversion operator or constructor and if the sec-
8617 ond standard conversion sequence of U1 is better than the second
8618 standard conversion sequence of U2. */
8620 /* Handle list-conversion with the same code even though it isn't always
8621 ranked as a user-defined conversion and it doesn't have a second
8622 standard conversion sequence; it will still have the desired effect.
8623 Specifically, we need to do the reference binding comparison at the
8624 end of this function. */
8626 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
|| ics1
->kind
== ck_aggr
)
8631 for (t1
= ics1
; t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
8632 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
8633 || t1
->kind
== ck_list
)
8635 for (t2
= ics2
; t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
8636 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
8637 || t2
->kind
== ck_list
)
8640 if (t1
->kind
!= t2
->kind
)
8642 else if (t1
->kind
== ck_user
)
8644 if (t1
->cand
->fn
!= t2
->cand
->fn
)
8649 /* For ambiguous or aggregate conversions, use the target type as
8650 a proxy for the conversion function. */
8651 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
8655 /* We can just fall through here, after setting up
8656 FROM_TYPE1 and FROM_TYPE2. */
8657 from_type1
= t1
->type
;
8658 from_type2
= t2
->type
;
8665 /* We're dealing with two standard conversion sequences.
8669 Standard conversion sequence S1 is a better conversion
8670 sequence than standard conversion sequence S2 if
8672 --S1 is a proper subsequence of S2 (comparing the conversion
8673 sequences in the canonical form defined by _over.ics.scs_,
8674 excluding any Lvalue Transformation; the identity
8675 conversion sequence is considered to be a subsequence of
8676 any non-identity conversion sequence */
8679 while (t1
->kind
!= ck_identity
)
8680 t1
= next_conversion (t1
);
8681 from_type1
= t1
->type
;
8684 while (t2
->kind
!= ck_identity
)
8685 t2
= next_conversion (t2
);
8686 from_type2
= t2
->type
;
8689 /* One sequence can only be a subsequence of the other if they start with
8690 the same type. They can start with different types when comparing the
8691 second standard conversion sequence in two user-defined conversion
8693 if (same_type_p (from_type1
, from_type2
))
8695 if (is_subseq (ics1
, ics2
))
8697 if (is_subseq (ics2
, ics1
))
8705 --the rank of S1 is better than the rank of S2 (by the rules
8708 Standard conversion sequences are ordered by their ranks: an Exact
8709 Match is a better conversion than a Promotion, which is a better
8710 conversion than a Conversion.
8712 Two conversion sequences with the same rank are indistinguishable
8713 unless one of the following rules applies:
8715 --A conversion that does not a convert a pointer, pointer to member,
8716 or std::nullptr_t to bool is better than one that does.
8718 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
8719 so that we do not have to check it explicitly. */
8720 if (ics1
->rank
< ics2
->rank
)
8722 else if (ics2
->rank
< ics1
->rank
)
8725 to_type1
= ics1
->type
;
8726 to_type2
= ics2
->type
;
8728 /* A conversion from scalar arithmetic type to complex is worse than a
8729 conversion between scalar arithmetic types. */
8730 if (same_type_p (from_type1
, from_type2
)
8731 && ARITHMETIC_TYPE_P (from_type1
)
8732 && ARITHMETIC_TYPE_P (to_type1
)
8733 && ARITHMETIC_TYPE_P (to_type2
)
8734 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
8735 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
8737 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
8743 if (TYPE_PTR_P (from_type1
)
8744 && TYPE_PTR_P (from_type2
)
8745 && TYPE_PTR_P (to_type1
)
8746 && TYPE_PTR_P (to_type2
))
8748 deref_from_type1
= TREE_TYPE (from_type1
);
8749 deref_from_type2
= TREE_TYPE (from_type2
);
8750 deref_to_type1
= TREE_TYPE (to_type1
);
8751 deref_to_type2
= TREE_TYPE (to_type2
);
8753 /* The rules for pointers to members A::* are just like the rules
8754 for pointers A*, except opposite: if B is derived from A then
8755 A::* converts to B::*, not vice versa. For that reason, we
8756 switch the from_ and to_ variables here. */
8757 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
8758 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
8759 || (TYPE_PTRMEMFUNC_P (from_type1
)
8760 && TYPE_PTRMEMFUNC_P (from_type2
)
8761 && TYPE_PTRMEMFUNC_P (to_type1
)
8762 && TYPE_PTRMEMFUNC_P (to_type2
)))
8764 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
8765 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
8766 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
8767 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
8770 if (deref_from_type1
!= NULL_TREE
8771 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
8772 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
8774 /* This was one of the pointer or pointer-like conversions.
8778 --If class B is derived directly or indirectly from class A,
8779 conversion of B* to A* is better than conversion of B* to
8780 void*, and conversion of A* to void* is better than
8781 conversion of B* to void*. */
8782 if (VOID_TYPE_P (deref_to_type1
)
8783 && VOID_TYPE_P (deref_to_type2
))
8785 if (is_properly_derived_from (deref_from_type1
,
8788 else if (is_properly_derived_from (deref_from_type2
,
8792 else if (VOID_TYPE_P (deref_to_type1
)
8793 || VOID_TYPE_P (deref_to_type2
))
8795 if (same_type_p (deref_from_type1
, deref_from_type2
))
8797 if (VOID_TYPE_P (deref_to_type2
))
8799 if (is_properly_derived_from (deref_from_type1
,
8803 /* We know that DEREF_TO_TYPE1 is `void' here. */
8804 else if (is_properly_derived_from (deref_from_type1
,
8809 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
8810 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
8814 --If class B is derived directly or indirectly from class A
8815 and class C is derived directly or indirectly from B,
8817 --conversion of C* to B* is better than conversion of C* to
8820 --conversion of B* to A* is better than conversion of C* to
8822 if (same_type_p (deref_from_type1
, deref_from_type2
))
8824 if (is_properly_derived_from (deref_to_type1
,
8827 else if (is_properly_derived_from (deref_to_type2
,
8831 else if (same_type_p (deref_to_type1
, deref_to_type2
))
8833 if (is_properly_derived_from (deref_from_type2
,
8836 else if (is_properly_derived_from (deref_from_type1
,
8842 else if (CLASS_TYPE_P (non_reference (from_type1
))
8843 && same_type_p (from_type1
, from_type2
))
8845 tree from
= non_reference (from_type1
);
8849 --binding of an expression of type C to a reference of type
8850 B& is better than binding an expression of type C to a
8851 reference of type A&
8853 --conversion of C to B is better than conversion of C to A, */
8854 if (is_properly_derived_from (from
, to_type1
)
8855 && is_properly_derived_from (from
, to_type2
))
8857 if (is_properly_derived_from (to_type1
, to_type2
))
8859 else if (is_properly_derived_from (to_type2
, to_type1
))
8863 else if (CLASS_TYPE_P (non_reference (to_type1
))
8864 && same_type_p (to_type1
, to_type2
))
8866 tree to
= non_reference (to_type1
);
8870 --binding of an expression of type B to a reference of type
8871 A& is better than binding an expression of type C to a
8872 reference of type A&,
8874 --conversion of B to A is better than conversion of C to A */
8875 if (is_properly_derived_from (from_type1
, to
)
8876 && is_properly_derived_from (from_type2
, to
))
8878 if (is_properly_derived_from (from_type2
, from_type1
))
8880 else if (is_properly_derived_from (from_type1
, from_type2
))
8887 --S1 and S2 differ only in their qualification conversion and yield
8888 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
8889 qualification signature of type T1 is a proper subset of the cv-
8890 qualification signature of type T2 */
8891 if (ics1
->kind
== ck_qual
8892 && ics2
->kind
== ck_qual
8893 && same_type_p (from_type1
, from_type2
))
8895 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
8902 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
8903 to an implicit object parameter of a non-static member function
8904 declared without a ref-qualifier, and either S1 binds an lvalue
8905 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
8906 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
8907 draft standard, 13.3.3.2)
8909 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
8910 types to which the references refer are the same type except for
8911 top-level cv-qualifiers, and the type to which the reference
8912 initialized by S2 refers is more cv-qualified than the type to
8913 which the reference initialized by S1 refers.
8915 DR 1328 [over.match.best]: the context is an initialization by
8916 conversion function for direct reference binding (13.3.1.6) of a
8917 reference to function type, the return type of F1 is the same kind of
8918 reference (i.e. lvalue or rvalue) as the reference being initialized,
8919 and the return type of F2 is not. */
8921 if (ref_conv1
&& ref_conv2
)
8923 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
8924 && (ref_conv1
->rvaluedness_matches_p
8925 != ref_conv2
->rvaluedness_matches_p
)
8926 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
8927 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
8928 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
8930 if (ref_conv1
->bad_p
8931 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
8932 TREE_TYPE (ref_conv2
->type
)))
8933 /* Don't prefer a bad conversion that drops cv-quals to a bad
8934 conversion with the wrong rvalueness. */
8936 return (ref_conv1
->rvaluedness_matches_p
8937 - ref_conv2
->rvaluedness_matches_p
);
8940 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
8942 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
8943 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
8944 if (ref_conv1
->bad_p
)
8946 /* Prefer the one that drops fewer cv-quals. */
8947 tree ftype
= next_conversion (ref_conv1
)->type
;
8948 int fquals
= cp_type_quals (ftype
);
8952 return comp_cv_qualification (q2
, q1
);
8956 /* Neither conversion sequence is better than the other. */
8960 /* The source type for this standard conversion sequence. */
8963 source_type (conversion
*t
)
8965 for (;; t
= next_conversion (t
))
8967 if (t
->kind
== ck_user
8968 || t
->kind
== ck_ambig
8969 || t
->kind
== ck_identity
)
8975 /* Note a warning about preferring WINNER to LOSER. We do this by storing
8976 a pointer to LOSER and re-running joust to produce the warning if WINNER
8977 is actually used. */
8980 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
8982 candidate_warning
*cw
= (candidate_warning
*)
8983 conversion_obstack_alloc (sizeof (candidate_warning
));
8985 cw
->next
= winner
->warnings
;
8986 winner
->warnings
= cw
;
8989 /* Compare two candidates for overloading as described in
8990 [over.match.best]. Return values:
8992 1: cand1 is better than cand2
8993 -1: cand2 is better than cand1
8994 0: cand1 and cand2 are indistinguishable */
8997 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
8998 tsubst_flags_t complain
)
9001 int off1
= 0, off2
= 0;
9005 /* Candidates that involve bad conversions are always worse than those
9007 if (cand1
->viable
> cand2
->viable
)
9009 if (cand1
->viable
< cand2
->viable
)
9012 /* If we have two pseudo-candidates for conversions to the same type,
9013 or two candidates for the same function, arbitrarily pick one. */
9014 if (cand1
->fn
== cand2
->fn
9015 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
9018 /* Prefer a non-deleted function over an implicitly deleted move
9019 constructor or assignment operator. This differs slightly from the
9020 wording for issue 1402 (which says the move op is ignored by overload
9021 resolution), but this way produces better error messages. */
9022 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
9023 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
9024 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
9026 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
9027 && move_fn_p (cand1
->fn
))
9029 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
9030 && move_fn_p (cand2
->fn
))
9034 /* a viable function F1
9035 is defined to be a better function than another viable function F2 if
9036 for all arguments i, ICSi(F1) is not a worse conversion sequence than
9037 ICSi(F2), and then */
9039 /* for some argument j, ICSj(F1) is a better conversion sequence than
9042 /* For comparing static and non-static member functions, we ignore
9043 the implicit object parameter of the non-static function. The
9044 standard says to pretend that the static function has an object
9045 parm, but that won't work with operator overloading. */
9046 len
= cand1
->num_convs
;
9047 if (len
!= cand2
->num_convs
)
9049 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
9050 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
9052 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
9053 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
9054 /* We're comparing a near-match list constructor and a near-match
9055 non-list constructor. Just treat them as unordered. */
9058 gcc_assert (static_1
!= static_2
);
9069 for (i
= 0; i
< len
; ++i
)
9071 conversion
*t1
= cand1
->convs
[i
+ off1
];
9072 conversion
*t2
= cand2
->convs
[i
+ off2
];
9073 int comp
= compare_ics (t1
, t2
);
9077 if ((complain
& tf_warning
)
9079 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
9080 == cr_std
+ cr_promotion
)
9081 && t1
->kind
== ck_std
9082 && t2
->kind
== ck_std
9083 && TREE_CODE (t1
->type
) == INTEGER_TYPE
9084 && TREE_CODE (t2
->type
) == INTEGER_TYPE
9085 && (TYPE_PRECISION (t1
->type
)
9086 == TYPE_PRECISION (t2
->type
))
9087 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
9088 || (TREE_CODE (next_conversion (t1
)->type
)
9091 tree type
= next_conversion (t1
)->type
;
9093 struct z_candidate
*w
, *l
;
9095 type1
= t1
->type
, type2
= t2
->type
,
9096 w
= cand1
, l
= cand2
;
9098 type1
= t2
->type
, type2
= t1
->type
,
9099 w
= cand2
, l
= cand1
;
9103 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
9104 type
, type1
, type2
);
9105 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
9111 if (winner
&& comp
!= winner
)
9120 /* warn about confusing overload resolution for user-defined conversions,
9121 either between a constructor and a conversion op, or between two
9123 if ((complain
& tf_warning
)
9124 && winner
&& warn_conversion
&& cand1
->second_conv
9125 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
9126 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
9128 struct z_candidate
*w
, *l
;
9129 bool give_warning
= false;
9132 w
= cand1
, l
= cand2
;
9134 w
= cand2
, l
= cand1
;
9136 /* We don't want to complain about `X::operator T1 ()'
9137 beating `X::operator T2 () const', when T2 is a no less
9138 cv-qualified version of T1. */
9139 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
9140 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
9142 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
9143 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
9145 if (TREE_CODE (t
) == TREE_CODE (f
) && POINTER_TYPE_P (t
))
9150 if (!comp_ptr_ttypes (t
, f
))
9151 give_warning
= true;
9154 give_warning
= true;
9160 tree source
= source_type (w
->convs
[0]);
9161 if (! DECL_CONSTRUCTOR_P (w
->fn
))
9162 source
= TREE_TYPE (source
);
9163 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
9164 && warning (OPT_Wconversion
, " for conversion from %qT to %qT",
9165 source
, w
->second_conv
->type
))
9167 inform (input_location
, " because conversion sequence for the argument is better");
9177 /* DR 495 moved this tiebreaker above the template ones. */
9179 the context is an initialization by user-defined conversion (see
9180 _dcl.init_ and _over.match.user_) and the standard conversion
9181 sequence from the return type of F1 to the destination type (i.e.,
9182 the type of the entity being initialized) is a better conversion
9183 sequence than the standard conversion sequence from the return type
9184 of F2 to the destination type. */
9186 if (cand1
->second_conv
)
9188 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
9194 F1 is a non-template function and F2 is a template function
9197 if (!cand1
->template_decl
&& cand2
->template_decl
)
9199 else if (cand1
->template_decl
&& !cand2
->template_decl
)
9203 F1 and F2 are template functions and the function template for F1 is
9204 more specialized than the template for F2 according to the partial
9207 if (cand1
->template_decl
&& cand2
->template_decl
)
9209 winner
= more_specialized_fn
9210 (TI_TEMPLATE (cand1
->template_decl
),
9211 TI_TEMPLATE (cand2
->template_decl
),
9212 /* [temp.func.order]: The presence of unused ellipsis and default
9213 arguments has no effect on the partial ordering of function
9214 templates. add_function_candidate() will not have
9215 counted the "this" argument for constructors. */
9216 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
9222 // or, if not that, F1 is more constrained than F2.
9223 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
9225 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
9230 /* Check whether we can discard a builtin candidate, either because we
9231 have two identical ones or matching builtin and non-builtin candidates.
9233 (Pedantically in the latter case the builtin which matched the user
9234 function should not be added to the overload set, but we spot it here.
9237 ... the builtin candidates include ...
9238 - do not have the same parameter type list as any non-template
9239 non-member candidate. */
9241 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
9243 for (i
= 0; i
< len
; ++i
)
9244 if (!same_type_p (cand1
->convs
[i
]->type
,
9245 cand2
->convs
[i
]->type
))
9247 if (i
== cand1
->num_convs
)
9249 if (cand1
->fn
== cand2
->fn
)
9250 /* Two built-in candidates; arbitrarily pick one. */
9252 else if (identifier_p (cand1
->fn
))
9253 /* cand1 is built-in; prefer cand2. */
9256 /* cand2 is built-in; prefer cand1. */
9261 /* For candidates of a multi-versioned function, make the version with
9262 the highest priority win. This version will be checked for dispatching
9263 first. If this version can be inlined into the caller, the front-end
9264 will simply make a direct call to this function. */
9266 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
9267 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
9268 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
9269 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
9271 tree f1
= TREE_TYPE (cand1
->fn
);
9272 tree f2
= TREE_TYPE (cand2
->fn
);
9273 tree p1
= TYPE_ARG_TYPES (f1
);
9274 tree p2
= TYPE_ARG_TYPES (f2
);
9276 /* Check if cand1->fn and cand2->fn are versions of the same function. It
9277 is possible that cand1->fn and cand2->fn are function versions but of
9278 different functions. Check types to see if they are versions of the same
9280 if (compparms (p1
, p2
)
9281 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
9283 /* Always make the version with the higher priority, more
9284 specialized, win. */
9285 gcc_assert (targetm
.compare_version_priority
);
9286 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
9293 /* If the two function declarations represent the same function (this can
9294 happen with declarations in multiple scopes and arg-dependent lookup),
9295 arbitrarily choose one. But first make sure the default args we're
9297 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
9298 && equal_functions (cand1
->fn
, cand2
->fn
))
9300 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
9301 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
9303 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
9305 for (i
= 0; i
< len
; ++i
)
9307 /* Don't crash if the fn is variadic. */
9310 parms1
= TREE_CHAIN (parms1
);
9311 parms2
= TREE_CHAIN (parms2
);
9315 parms1
= TREE_CHAIN (parms1
);
9317 parms2
= TREE_CHAIN (parms2
);
9321 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
9322 TREE_PURPOSE (parms2
)))
9326 if (complain
& tf_error
)
9328 if (permerror (input_location
,
9329 "default argument mismatch in "
9330 "overload resolution"))
9332 inform (input_location
,
9333 " candidate 1: %q+#F", cand1
->fn
);
9334 inform (input_location
,
9335 " candidate 2: %q+#F", cand2
->fn
);
9342 add_warning (cand1
, cand2
);
9345 parms1
= TREE_CHAIN (parms1
);
9346 parms2
= TREE_CHAIN (parms2
);
9354 /* Extension: If the worst conversion for one candidate is worse than the
9355 worst conversion for the other, take the first. */
9356 if (!pedantic
&& (complain
& tf_warning_or_error
))
9358 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
9359 struct z_candidate
*w
= 0, *l
= 0;
9361 for (i
= 0; i
< len
; ++i
)
9363 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
9364 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
9365 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
9366 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
9369 winner
= 1, w
= cand1
, l
= cand2
;
9371 winner
= -1, w
= cand2
, l
= cand1
;
9374 /* Don't choose a deleted function over ambiguity. */
9375 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
9379 pedwarn (input_location
, 0,
9380 "ISO C++ says that these are ambiguous, even "
9381 "though the worst conversion for the first is better than "
9382 "the worst conversion for the second:");
9383 print_z_candidate (input_location
, _("candidate 1:"), w
);
9384 print_z_candidate (input_location
, _("candidate 2:"), l
);
9392 gcc_assert (!winner
);
9396 /* Given a list of candidates for overloading, find the best one, if any.
9397 This algorithm has a worst case of O(2n) (winner is last), and a best
9398 case of O(n/2) (totally ambiguous); much better than a sorting
9401 static struct z_candidate
*
9402 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
9404 struct z_candidate
*champ
= candidates
, *challenger
;
9406 int champ_compared_to_predecessor
= 0;
9408 /* Walk through the list once, comparing each current champ to the next
9409 candidate, knocking out a candidate or two with each comparison. */
9411 for (challenger
= champ
->next
; challenger
; )
9413 fate
= joust (champ
, challenger
, 0, complain
);
9415 challenger
= challenger
->next
;
9420 champ
= challenger
->next
;
9423 champ_compared_to_predecessor
= 0;
9428 champ_compared_to_predecessor
= 1;
9431 challenger
= champ
->next
;
9435 /* Make sure the champ is better than all the candidates it hasn't yet
9436 been compared to. */
9438 for (challenger
= candidates
;
9440 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
9441 challenger
= challenger
->next
)
9443 fate
= joust (champ
, challenger
, 0, complain
);
9451 /* Returns nonzero if things of type FROM can be converted to TO. */
9454 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
9456 tree arg
= NULL_TREE
;
9457 /* implicit_conversion only considers user-defined conversions
9458 if it has an expression for the call argument list. */
9459 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
9460 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
9461 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
9464 /* Returns nonzero if things of type FROM can be converted to TO with a
9465 standard conversion. */
9468 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
9470 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
9473 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
9476 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
9477 tsubst_flags_t complain
)
9483 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9484 p
= conversion_obstack_alloc (0);
9485 /* We want to discard any access checks done for this test,
9486 as we might not be in the appropriate access context and
9487 we'll do the check again when we actually perform the
9489 push_deferring_access_checks (dk_deferred
);
9491 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
9493 ok_p
= (t
&& !t
->bad_p
);
9495 /* Discard the access checks now. */
9496 pop_deferring_access_checks ();
9497 /* Free all the conversions we allocated. */
9498 obstack_free (&conversion_obstack
, p
);
9503 /* Like can_convert_arg, but allows dubious conversions as well. */
9506 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
9507 tsubst_flags_t complain
)
9512 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9513 p
= conversion_obstack_alloc (0);
9514 /* Try to perform the conversion. */
9515 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
9517 /* Free all the conversions we allocated. */
9518 obstack_free (&conversion_obstack
, p
);
9523 /* Convert EXPR to TYPE. Return the converted expression.
9525 Note that we allow bad conversions here because by the time we get to
9526 this point we are committed to doing the conversion. If we end up
9527 doing a bad conversion, convert_like will complain. */
9530 perform_implicit_conversion_flags (tree type
, tree expr
,
9531 tsubst_flags_t complain
, int flags
)
9535 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
9537 if (error_operand_p (expr
))
9538 return error_mark_node
;
9540 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9541 p
= conversion_obstack_alloc (0);
9543 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
9549 if (complain
& tf_error
)
9551 /* If expr has unknown type, then it is an overloaded function.
9552 Call instantiate_type to get good error messages. */
9553 if (TREE_TYPE (expr
) == unknown_type_node
)
9554 instantiate_type (type
, expr
, complain
);
9555 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
9556 /* We gave an error. */;
9558 error_at (loc
, "could not convert %qE from %qT to %qT", expr
,
9559 TREE_TYPE (expr
), type
);
9561 expr
= error_mark_node
;
9563 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
9565 /* In a template, we are only concerned about determining the
9566 type of non-dependent expressions, so we do not have to
9567 perform the actual conversion. But for initializers, we
9568 need to be able to perform it at instantiation
9569 (or instantiate_non_dependent_expr) time. */
9570 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
9571 if (!(flags
& LOOKUP_ONLYCONVERTING
))
9572 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
9575 expr
= convert_like (conv
, expr
, complain
);
9577 /* Free all the conversions we allocated. */
9578 obstack_free (&conversion_obstack
, p
);
9584 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
9586 return perform_implicit_conversion_flags (type
, expr
, complain
,
9590 /* Convert EXPR to TYPE (as a direct-initialization) if that is
9591 permitted. If the conversion is valid, the converted expression is
9592 returned. Otherwise, NULL_TREE is returned, except in the case
9593 that TYPE is a class type; in that case, an error is issued. If
9594 C_CAST_P is true, then this direct-initialization is taking
9595 place as part of a static_cast being attempted as part of a C-style
9599 perform_direct_initialization_if_possible (tree type
,
9602 tsubst_flags_t complain
)
9607 if (type
== error_mark_node
|| error_operand_p (expr
))
9608 return error_mark_node
;
9611 If the destination type is a (possibly cv-qualified) class type:
9613 -- If the initialization is direct-initialization ...,
9614 constructors are considered. ... If no constructor applies, or
9615 the overload resolution is ambiguous, the initialization is
9617 if (CLASS_TYPE_P (type
))
9619 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
9620 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
9621 &args
, type
, LOOKUP_NORMAL
, complain
);
9622 release_tree_vector (args
);
9623 return build_cplus_new (type
, expr
, complain
);
9626 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9627 p
= conversion_obstack_alloc (0);
9629 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
9631 LOOKUP_NORMAL
, complain
);
9632 if (!conv
|| conv
->bad_p
)
9635 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0, 0,
9636 /*issue_conversion_warnings=*/false,
9640 /* Free all the conversions we allocated. */
9641 obstack_free (&conversion_obstack
, p
);
9646 /* When initializing a reference that lasts longer than a full-expression,
9647 this special rule applies:
9651 The temporary to which the reference is bound or the temporary
9652 that is the complete object to which the reference is bound
9653 persists for the lifetime of the reference.
9655 The temporaries created during the evaluation of the expression
9656 initializing the reference, except the temporary to which the
9657 reference is bound, are destroyed at the end of the
9658 full-expression in which they are created.
9660 In that case, we store the converted expression into a new
9661 VAR_DECL in a new scope.
9663 However, we want to be careful not to create temporaries when
9664 they are not required. For example, given:
9667 struct D : public B {};
9671 there is no need to copy the return value from "f"; we can just
9672 extend its lifetime. Similarly, given:
9675 struct T { operator S(); };
9679 we can extend the lifetime of the return value of the conversion
9682 The next several functions are involved in this lifetime extension. */
9684 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
9685 reference is being bound to a temporary. Create and return a new
9686 VAR_DECL with the indicated TYPE; this variable will store the value to
9687 which the reference is bound. */
9690 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
9694 /* Create the variable. */
9695 var
= create_temporary_var (type
);
9697 /* Register the variable. */
9699 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
9701 /* Namespace-scope or local static; give it a mangled name. */
9702 /* FIXME share comdat with decl? */
9705 TREE_STATIC (var
) = TREE_STATIC (decl
);
9706 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
9707 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
9708 name
= mangle_ref_init_variable (decl
);
9709 DECL_NAME (var
) = name
;
9710 SET_DECL_ASSEMBLER_NAME (var
, name
);
9711 var
= pushdecl_top_level (var
);
9714 /* Create a new cleanup level if necessary. */
9715 maybe_push_cleanup_level (type
);
9720 /* EXPR is the initializer for a variable DECL of reference or
9721 std::initializer_list type. Create, push and return a new VAR_DECL
9722 for the initializer so that it will live as long as DECL. Any
9723 cleanup for the new variable is returned through CLEANUP, and the
9724 code to initialize the new variable is returned through INITP. */
9727 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
9734 /* Create the temporary variable. */
9735 type
= TREE_TYPE (expr
);
9736 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
9737 layout_decl (var
, 0);
9738 /* If the rvalue is the result of a function call it will be
9739 a TARGET_EXPR. If it is some other construct (such as a
9740 member access expression where the underlying object is
9741 itself the result of a function call), turn it into a
9742 TARGET_EXPR here. It is important that EXPR be a
9743 TARGET_EXPR below since otherwise the INIT_EXPR will
9744 attempt to make a bitwise copy of EXPR to initialize
9746 if (TREE_CODE (expr
) != TARGET_EXPR
)
9747 expr
= get_target_expr (expr
);
9749 if (TREE_CODE (decl
) == FIELD_DECL
9750 && extra_warnings
&& !TREE_NO_WARNING (decl
))
9752 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
9753 "until the constructor exits", decl
);
9754 TREE_NO_WARNING (decl
) = true;
9757 /* Recursively extend temps in this initializer. */
9758 TARGET_EXPR_INITIAL (expr
)
9759 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
9761 /* Any reference temp has a non-trivial initializer. */
9762 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
9764 /* If the initializer is constant, put it in DECL_INITIAL so we get
9765 static initialization and use in constant expressions. */
9766 init
= maybe_constant_init (expr
);
9767 if (TREE_CONSTANT (init
))
9769 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
9771 /* 5.19 says that a constant expression can include an
9772 lvalue-rvalue conversion applied to "a glvalue of literal type
9773 that refers to a non-volatile temporary object initialized
9774 with a constant expression". Rather than try to communicate
9775 that this VAR_DECL is a temporary, just mark it constexpr.
9777 Currently this is only useful for initializer_list temporaries,
9778 since reference vars can't appear in constant expressions. */
9779 DECL_DECLARED_CONSTEXPR_P (var
) = true;
9780 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
9781 TREE_CONSTANT (var
) = true;
9783 DECL_INITIAL (var
) = init
;
9787 /* Create the INIT_EXPR that will initialize the temporary
9789 init
= split_nonconstant_init (var
, expr
);
9790 if (at_function_scope_p ())
9792 add_decl_expr (var
);
9794 if (TREE_STATIC (var
))
9795 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
9798 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
9800 vec_safe_push (*cleanups
, cleanup
);
9803 /* We must be careful to destroy the temporary only
9804 after its initialization has taken place. If the
9805 initialization throws an exception, then the
9806 destructor should not be run. We cannot simply
9807 transform INIT into something like:
9809 (INIT, ({ CLEANUP_STMT; }))
9811 because emit_local_var always treats the
9812 initializer as a full-expression. Thus, the
9813 destructor would run too early; it would run at the
9814 end of initializing the reference variable, rather
9815 than at the end of the block enclosing the
9818 The solution is to pass back a cleanup expression
9819 which the caller is responsible for attaching to
9820 the statement tree. */
9824 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
9825 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
9827 if (CP_DECL_THREAD_LOCAL_P (var
))
9828 tls_aggregates
= tree_cons (NULL_TREE
, var
,
9831 static_aggregates
= tree_cons (NULL_TREE
, var
,
9835 /* Check whether the dtor is callable. */
9836 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
9838 /* Avoid -Wunused-variable warning (c++/38958). */
9839 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
9841 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
9847 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
9848 initializing a variable of that TYPE. */
9851 initialize_reference (tree type
, tree expr
,
9852 int flags
, tsubst_flags_t complain
)
9856 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
9858 if (type
== error_mark_node
|| error_operand_p (expr
))
9859 return error_mark_node
;
9861 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9862 p
= conversion_obstack_alloc (0);
9864 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
9866 if (!conv
|| conv
->bad_p
)
9868 if (complain
& tf_error
)
9871 convert_like (conv
, expr
, complain
);
9872 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
9873 && !TYPE_REF_IS_RVALUE (type
)
9874 && !real_lvalue_p (expr
))
9875 error_at (loc
, "invalid initialization of non-const reference of "
9876 "type %qT from an rvalue of type %qT",
9877 type
, TREE_TYPE (expr
));
9879 error_at (loc
, "invalid initialization of reference of type "
9880 "%qT from expression of type %qT", type
,
9883 return error_mark_node
;
9886 if (conv
->kind
== ck_ref_bind
)
9887 /* Perform the conversion. */
9888 expr
= convert_like (conv
, expr
, complain
);
9889 else if (conv
->kind
== ck_ambig
)
9890 /* We gave an error in build_user_type_conversion_1. */
9891 expr
= error_mark_node
;
9895 /* Free all the conversions we allocated. */
9896 obstack_free (&conversion_obstack
, p
);
9901 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
9902 which is bound either to a reference or a std::initializer_list. */
9905 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
9910 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
9912 TREE_OPERAND (sub
, 1)
9913 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
9916 if (TREE_CODE (sub
) != ADDR_EXPR
)
9918 /* Deal with binding to a subobject. */
9919 for (p
= &TREE_OPERAND (sub
, 0); TREE_CODE (*p
) == COMPONENT_REF
; )
9920 p
= &TREE_OPERAND (*p
, 0);
9921 if (TREE_CODE (*p
) == TARGET_EXPR
)
9923 tree subinit
= NULL_TREE
;
9924 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
9925 recompute_tree_invariant_for_addr_expr (sub
);
9927 init
= fold_convert (TREE_TYPE (init
), sub
);
9929 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
9934 /* INIT is part of the initializer for DECL. If there are any
9935 reference or initializer lists being initialized, extend their
9936 lifetime to match that of DECL. */
9939 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
9941 tree type
= TREE_TYPE (init
);
9942 if (processing_template_decl
)
9944 if (TREE_CODE (type
) == REFERENCE_TYPE
)
9945 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
9946 else if (is_std_init_list (type
))
9948 /* The temporary array underlying a std::initializer_list
9949 is handled like a reference temporary. */
9951 if (TREE_CODE (ctor
) == TARGET_EXPR
)
9952 ctor
= TARGET_EXPR_INITIAL (ctor
);
9953 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
9955 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
9956 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
9957 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
9960 else if (TREE_CODE (init
) == CONSTRUCTOR
)
9964 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (init
);
9965 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
9966 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
9972 /* Returns true iff an initializer for TYPE could contain temporaries that
9973 need to be extended because they are bound to references or
9974 std::initializer_list. */
9977 type_has_extended_temps (tree type
)
9979 type
= strip_array_types (type
);
9980 if (TREE_CODE (type
) == REFERENCE_TYPE
)
9982 if (CLASS_TYPE_P (type
))
9984 if (is_std_init_list (type
))
9986 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
9987 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
9988 if (type_has_extended_temps (TREE_TYPE (f
)))
9994 /* Returns true iff TYPE is some variant of std::initializer_list. */
9997 is_std_init_list (tree type
)
9999 /* Look through typedefs. */
10000 if (!TYPE_P (type
))
10002 if (cxx_dialect
== cxx98
)
10004 type
= TYPE_MAIN_VARIANT (type
);
10005 return (CLASS_TYPE_P (type
)
10006 && CP_TYPE_CONTEXT (type
) == std_node
10007 && strcmp (TYPE_NAME_STRING (type
), "initializer_list") == 0);
10010 /* Returns true iff DECL is a list constructor: i.e. a constructor which
10011 will accept an argument list of a single std::initializer_list<T>. */
10014 is_list_ctor (tree decl
)
10016 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
10019 if (!args
|| args
== void_list_node
)
10022 arg
= non_reference (TREE_VALUE (args
));
10023 if (!is_std_init_list (arg
))
10026 args
= TREE_CHAIN (args
);
10028 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
10029 /* There are more non-defaulted parms. */
10035 #include "gt-cp-call.h"