1 /* Functions related to invoking -*- C++ -*- methods and overloaded functions.
2 Copyright (C) 1987-2018 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com) and
4 modified by Brendan Kehoe (brendan@cygnus.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* High-level class interface. */
27 #include "coretypes.h"
31 #include "stringpool.h"
33 #include "stor-layout.h"
34 #include "trans-mem.h"
39 #include "langhooks.h"
40 #include "c-family/c-objc.h"
41 #include "internal-fn.h"
42 #include "stringpool.h"
44 #include "gcc-rich-location.h"
46 /* The various kinds of conversion. */
48 enum conversion_kind
{
65 /* The rank of the conversion. Order of the enumerals matters; better
66 conversions should come earlier in the list. */
68 enum conversion_rank
{
79 /* An implicit conversion sequence, in the sense of [over.best.ics].
80 The first conversion to be performed is at the end of the chain.
81 That conversion is always a cr_identity conversion. */
84 /* The kind of conversion represented by this step. */
86 /* The rank of this conversion. */
88 BOOL_BITFIELD user_conv_p
: 1;
89 BOOL_BITFIELD ellipsis_p
: 1;
90 BOOL_BITFIELD this_p
: 1;
91 /* True if this conversion would be permitted with a bending of
92 language standards, e.g. disregarding pointer qualifiers or
93 converting integers to pointers. */
94 BOOL_BITFIELD bad_p
: 1;
95 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
96 temporary should be created to hold the result of the
97 conversion. If KIND is ck_ambig, true if the context is
98 copy-initialization. */
99 BOOL_BITFIELD need_temporary_p
: 1;
100 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
101 from a pointer-to-derived to pointer-to-base is being performed. */
102 BOOL_BITFIELD base_p
: 1;
103 /* If KIND is ck_ref_bind, true when either an lvalue reference is
104 being bound to an lvalue expression or an rvalue reference is
105 being bound to an rvalue expression. If KIND is ck_rvalue or ck_base,
106 true when we are treating an lvalue as an rvalue (12.8p33). If
107 ck_identity, we will be binding a reference directly or decaying to
109 BOOL_BITFIELD rvaluedness_matches_p
: 1;
110 BOOL_BITFIELD check_narrowing
: 1;
111 /* Whether check_narrowing should only check TREE_CONSTANTs; used
112 in build_converted_constant_expr. */
113 BOOL_BITFIELD check_narrowing_const_only
: 1;
114 /* The type of the expression resulting from the conversion. */
117 /* The next conversion in the chain. Since the conversions are
118 arranged from outermost to innermost, the NEXT conversion will
119 actually be performed before this conversion. This variant is
120 used only when KIND is neither ck_identity, ck_ambig nor
121 ck_list. Please use the next_conversion function instead
122 of using this field directly. */
124 /* The expression at the beginning of the conversion chain. This
125 variant is used only if KIND is ck_identity or ck_ambig. */
127 /* The array of conversions for an initializer_list, so this
128 variant is used only when KIN D is ck_list. */
131 /* The function candidate corresponding to this conversion
132 sequence. This field is only used if KIND is ck_user. */
133 struct z_candidate
*cand
;
136 #define CONVERSION_RANK(NODE) \
137 ((NODE)->bad_p ? cr_bad \
138 : (NODE)->ellipsis_p ? cr_ellipsis \
139 : (NODE)->user_conv_p ? cr_user \
142 #define BAD_CONVERSION_RANK(NODE) \
143 ((NODE)->ellipsis_p ? cr_ellipsis \
144 : (NODE)->user_conv_p ? cr_user \
147 static struct obstack conversion_obstack
;
148 static bool conversion_obstack_initialized
;
149 struct rejection_reason
;
151 static struct z_candidate
* tourney (struct z_candidate
*, tsubst_flags_t
);
152 static int equal_functions (tree
, tree
);
153 static int joust (struct z_candidate
*, struct z_candidate
*, bool,
155 static int compare_ics (conversion
*, conversion
*);
156 static void maybe_warn_class_memaccess (location_t
, tree
,
157 const vec
<tree
, va_gc
> *);
158 static tree
build_over_call (struct z_candidate
*, int, tsubst_flags_t
);
159 #define convert_like(CONV, EXPR, COMPLAIN) \
160 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, \
161 /*issue_conversion_warnings=*/true, \
162 /*c_cast_p=*/false, (COMPLAIN))
163 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
164 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), \
165 /*issue_conversion_warnings=*/true, \
166 /*c_cast_p=*/false, (COMPLAIN))
167 static tree
convert_like_real (conversion
*, tree
, tree
, int, bool,
168 bool, tsubst_flags_t
);
169 static void op_error (location_t
, enum tree_code
, enum tree_code
, tree
,
171 static struct z_candidate
*build_user_type_conversion_1 (tree
, tree
, int,
173 static void print_z_candidate (location_t
, const char *, struct z_candidate
*);
174 static void print_z_candidates (location_t
, struct z_candidate
*);
175 static tree
build_this (tree
);
176 static struct z_candidate
*splice_viable (struct z_candidate
*, bool, bool *);
177 static bool any_strictly_viable (struct z_candidate
*);
178 static struct z_candidate
*add_template_candidate
179 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
180 tree
, tree
, tree
, int, unification_kind_t
, tsubst_flags_t
);
181 static struct z_candidate
*add_template_candidate_real
182 (struct z_candidate
**, tree
, tree
, tree
, tree
, const vec
<tree
, va_gc
> *,
183 tree
, tree
, tree
, int, tree
, unification_kind_t
, tsubst_flags_t
);
184 static void add_builtin_candidates
185 (struct z_candidate
**, enum tree_code
, enum tree_code
,
186 tree
, tree
*, int, tsubst_flags_t
);
187 static void add_builtin_candidate
188 (struct z_candidate
**, enum tree_code
, enum tree_code
,
189 tree
, tree
, tree
, tree
*, tree
*, int, tsubst_flags_t
);
190 static bool is_complete (tree
);
191 static void build_builtin_candidate
192 (struct z_candidate
**, tree
, tree
, tree
, tree
*, tree
*,
193 int, tsubst_flags_t
);
194 static struct z_candidate
*add_conv_candidate
195 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
196 tree
, tsubst_flags_t
);
197 static struct z_candidate
*add_function_candidate
198 (struct z_candidate
**, tree
, tree
, tree
, const vec
<tree
, va_gc
> *, tree
,
199 tree
, int, conversion
**, tsubst_flags_t
);
200 static conversion
*implicit_conversion (tree
, tree
, tree
, bool, int,
202 static conversion
*reference_binding (tree
, tree
, tree
, bool, int,
204 static conversion
*build_conv (conversion_kind
, tree
, conversion
*);
205 static conversion
*build_list_conv (tree
, tree
, int, tsubst_flags_t
);
206 static conversion
*next_conversion (conversion
*);
207 static bool is_subseq (conversion
*, conversion
*);
208 static conversion
*maybe_handle_ref_bind (conversion
**);
209 static void maybe_handle_implicit_object (conversion
**);
210 static struct z_candidate
*add_candidate
211 (struct z_candidate
**, tree
, tree
, const vec
<tree
, va_gc
> *, size_t,
212 conversion
**, tree
, tree
, int, struct rejection_reason
*, int);
213 static tree
source_type (conversion
*);
214 static void add_warning (struct z_candidate
*, struct z_candidate
*);
215 static bool reference_compatible_p (tree
, tree
);
216 static conversion
*direct_reference_binding (tree
, conversion
*);
217 static bool promoted_arithmetic_type_p (tree
);
218 static conversion
*conditional_conversion (tree
, tree
, tsubst_flags_t
);
219 static char *name_as_c_string (tree
, tree
, bool *);
220 static tree
prep_operand (tree
);
221 static void add_candidates (tree
, tree
, const vec
<tree
, va_gc
> *, tree
, tree
,
222 bool, tree
, tree
, int, struct z_candidate
**,
224 static conversion
*merge_conversion_sequences (conversion
*, conversion
*);
225 static tree
build_temp (tree
, tree
, int, diagnostic_t
*, tsubst_flags_t
);
227 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
228 NAME can take many forms... */
231 check_dtor_name (tree basetype
, tree name
)
233 /* Just accept something we've already complained about. */
234 if (name
== error_mark_node
)
237 if (TREE_CODE (name
) == TYPE_DECL
)
238 name
= TREE_TYPE (name
);
239 else if (TYPE_P (name
))
241 else if (identifier_p (name
))
243 if ((MAYBE_CLASS_TYPE_P (basetype
)
244 || TREE_CODE (basetype
) == ENUMERAL_TYPE
)
245 && name
== constructor_name (basetype
))
248 name
= get_type_value (name
);
254 template <class T> struct S { ~S(); };
258 NAME will be a class template. */
259 gcc_assert (DECL_CLASS_TEMPLATE_P (name
));
263 if (!name
|| name
== error_mark_node
)
265 return same_type_p (TYPE_MAIN_VARIANT (basetype
), TYPE_MAIN_VARIANT (name
));
268 /* We want the address of a function or method. We avoid creating a
269 pointer-to-member function. */
272 build_addr_func (tree function
, tsubst_flags_t complain
)
274 tree type
= TREE_TYPE (function
);
276 /* We have to do these by hand to avoid real pointer to member
278 if (TREE_CODE (type
) == METHOD_TYPE
)
280 if (TREE_CODE (function
) == OFFSET_REF
)
282 tree object
= build_address (TREE_OPERAND (function
, 0));
283 return get_member_function_from_ptrfunc (&object
,
284 TREE_OPERAND (function
, 1),
287 function
= build_address (function
);
290 function
= decay_conversion (function
, complain
, /*reject_builtin=*/false);
295 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
296 POINTER_TYPE to those. Note, pointer to member function types
297 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
298 two variants. build_call_a is the primitive taking an array of
299 arguments, while build_call_n is a wrapper that handles varargs. */
302 build_call_n (tree function
, int n
, ...)
305 return build_call_a (function
, 0, NULL
);
308 tree
*argarray
= XALLOCAVEC (tree
, n
);
313 for (i
= 0; i
< n
; i
++)
314 argarray
[i
] = va_arg (ap
, tree
);
316 return build_call_a (function
, n
, argarray
);
320 /* Update various flags in cfun and the call itself based on what is being
321 called. Split out of build_call_a so that bot_manip can use it too. */
324 set_flags_from_callee (tree call
)
326 /* Handle both CALL_EXPRs and AGGR_INIT_EXPRs. */
327 tree decl
= cp_get_callee_fndecl_nofold (call
);
329 /* We check both the decl and the type; a function may be known not to
330 throw without being declared throw(). */
331 bool nothrow
= decl
&& TREE_NOTHROW (decl
);
332 tree callee
= cp_get_callee (call
);
334 nothrow
|= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (callee
)));
335 else if (TREE_CODE (call
) == CALL_EXPR
336 && internal_fn_flags (CALL_EXPR_IFN (call
)) & ECF_NOTHROW
)
339 if (!nothrow
&& at_function_scope_p () && cfun
&& cp_function_chain
)
340 cp_function_chain
->can_throw
= 1;
342 if (decl
&& TREE_THIS_VOLATILE (decl
) && cfun
&& cp_function_chain
)
343 current_function_returns_abnormally
= 1;
345 TREE_NOTHROW (call
) = nothrow
;
349 build_call_a (tree function
, int n
, tree
*argarray
)
356 function
= build_addr_func (function
, tf_warning_or_error
);
358 gcc_assert (TYPE_PTR_P (TREE_TYPE (function
)));
359 fntype
= TREE_TYPE (TREE_TYPE (function
));
360 gcc_assert (TREE_CODE (fntype
) == FUNCTION_TYPE
361 || TREE_CODE (fntype
) == METHOD_TYPE
);
362 result_type
= TREE_TYPE (fntype
);
363 /* An rvalue has no cv-qualifiers. */
364 if (SCALAR_TYPE_P (result_type
) || VOID_TYPE_P (result_type
))
365 result_type
= cv_unqualified (result_type
);
367 function
= build_call_array_loc (input_location
,
368 result_type
, function
, n
, argarray
);
369 set_flags_from_callee (function
);
371 decl
= get_callee_fndecl (function
);
373 if (decl
&& !TREE_USED (decl
))
375 /* We invoke build_call directly for several library
376 functions. These may have been declared normally if
377 we're building libgcc, so we can't just check
379 gcc_assert (DECL_ARTIFICIAL (decl
)
380 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl
)),
385 require_complete_eh_spec_types (fntype
, decl
);
387 TREE_HAS_CONSTRUCTOR (function
) = (decl
&& DECL_CONSTRUCTOR_P (decl
));
389 /* Don't pass empty class objects by value. This is useful
390 for tags in STL, which are used to control overload resolution.
391 We don't need to handle other cases of copying empty classes. */
392 if (!decl
|| !fndecl_built_in_p (decl
))
393 for (i
= 0; i
< n
; i
++)
395 tree arg
= CALL_EXPR_ARG (function
, i
);
396 if (is_empty_class (TREE_TYPE (arg
))
397 && ! TREE_ADDRESSABLE (TREE_TYPE (arg
)))
399 tree t
= build0 (EMPTY_CLASS_EXPR
, TREE_TYPE (arg
));
400 arg
= build2 (COMPOUND_EXPR
, TREE_TYPE (t
), arg
, t
);
401 CALL_EXPR_ARG (function
, i
) = arg
;
408 /* New overloading code. */
412 struct candidate_warning
{
414 candidate_warning
*next
;
417 /* Information for providing diagnostics about why overloading failed. */
419 enum rejection_reason_code
{
422 rr_explicit_conversion
,
423 rr_template_conversion
,
425 rr_bad_arg_conversion
,
426 rr_template_unification
,
429 rr_constraint_failure
432 struct conversion_info
{
433 /* The index of the argument, 0-based. */
435 /* The actual argument or its type. */
437 /* The type of the parameter. */
439 /* The location of the argument. */
443 struct rejection_reason
{
444 enum rejection_reason_code code
;
446 /* Information about an arity mismatch. */
448 /* The expected number of arguments. */
450 /* The actual number of arguments in the call. */
452 /* Whether the call was a varargs call. */
455 /* Information about an argument conversion mismatch. */
456 struct conversion_info conversion
;
457 /* Same, but for bad argument conversions. */
458 struct conversion_info bad_conversion
;
459 /* Information about template unification failures. These are the
460 parameters passed to fn_type_unification. */
468 unification_kind_t strict
;
470 } template_unification
;
471 /* Information about template instantiation failures. These are the
472 parameters passed to instantiate_template. */
476 } template_instantiation
;
481 /* The FUNCTION_DECL that will be called if this candidate is
482 selected by overload resolution. */
484 /* If not NULL_TREE, the first argument to use when calling this
487 /* The rest of the arguments to use when calling this function. If
488 there are no further arguments this may be NULL or it may be an
490 const vec
<tree
, va_gc
> *args
;
491 /* The implicit conversion sequences for each of the arguments to
494 /* The number of implicit conversion sequences. */
496 /* If FN is a user-defined conversion, the standard conversion
497 sequence from the type returned by FN to the desired destination
499 conversion
*second_conv
;
500 struct rejection_reason
*reason
;
501 /* If FN is a member function, the binfo indicating the path used to
502 qualify the name of FN at the call site. This path is used to
503 determine whether or not FN is accessible if it is selected by
504 overload resolution. The DECL_CONTEXT of FN will always be a
505 (possibly improper) base of this binfo. */
507 /* If FN is a non-static member function, the binfo indicating the
508 subobject to which the `this' pointer should be converted if FN
509 is selected by overload resolution. The type pointed to by
510 the `this' pointer must correspond to the most derived class
511 indicated by the CONVERSION_PATH. */
512 tree conversion_path
;
515 candidate_warning
*warnings
;
519 /* The flags active in add_candidate. */
523 /* Returns true iff T is a null pointer constant in the sense of
527 null_ptr_cst_p (tree t
)
529 tree type
= TREE_TYPE (t
);
533 A null pointer constant is an integral constant expression
534 (_expr.const_) rvalue of integer type that evaluates to zero or
535 an rvalue of type std::nullptr_t. */
536 if (NULLPTR_TYPE_P (type
))
539 if (cxx_dialect
>= cxx11
)
541 STRIP_ANY_LOCATION_WRAPPER (t
);
543 /* Core issue 903 says only literal 0 is a null pointer constant. */
544 if (TREE_CODE (type
) == INTEGER_TYPE
545 && !char_type_p (type
)
546 && TREE_CODE (t
) == INTEGER_CST
548 && !TREE_OVERFLOW (t
))
551 else if (CP_INTEGRAL_TYPE_P (type
))
553 t
= fold_non_dependent_expr (t
, tf_none
);
555 if (integer_zerop (t
) && !TREE_OVERFLOW (t
))
562 /* Returns true iff T is a null member pointer value (4.11). */
565 null_member_pointer_value_p (tree t
)
567 tree type
= TREE_TYPE (t
);
570 else if (TYPE_PTRMEMFUNC_P (type
))
571 return (TREE_CODE (t
) == CONSTRUCTOR
572 && integer_zerop (CONSTRUCTOR_ELT (t
, 0)->value
));
573 else if (TYPE_PTRDATAMEM_P (type
))
574 return integer_all_onesp (t
);
579 /* Returns nonzero if PARMLIST consists of only default parms,
580 ellipsis, and/or undeduced parameter packs. */
583 sufficient_parms_p (const_tree parmlist
)
585 for (; parmlist
&& parmlist
!= void_list_node
;
586 parmlist
= TREE_CHAIN (parmlist
))
587 if (!TREE_PURPOSE (parmlist
)
588 && !PACK_EXPANSION_P (TREE_VALUE (parmlist
)))
593 /* Allocate N bytes of memory from the conversion obstack. The memory
594 is zeroed before being returned. */
597 conversion_obstack_alloc (size_t n
)
600 if (!conversion_obstack_initialized
)
602 gcc_obstack_init (&conversion_obstack
);
603 conversion_obstack_initialized
= true;
605 p
= obstack_alloc (&conversion_obstack
, n
);
610 /* Allocate rejection reasons. */
612 static struct rejection_reason
*
613 alloc_rejection (enum rejection_reason_code code
)
615 struct rejection_reason
*p
;
616 p
= (struct rejection_reason
*) conversion_obstack_alloc (sizeof *p
);
621 static struct rejection_reason
*
622 arity_rejection (tree first_arg
, int expected
, int actual
)
624 struct rejection_reason
*r
= alloc_rejection (rr_arity
);
625 int adjust
= first_arg
!= NULL_TREE
;
626 r
->u
.arity
.expected
= expected
- adjust
;
627 r
->u
.arity
.actual
= actual
- adjust
;
631 static struct rejection_reason
*
632 arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
635 struct rejection_reason
*r
= alloc_rejection (rr_arg_conversion
);
636 int adjust
= first_arg
!= NULL_TREE
;
637 r
->u
.conversion
.n_arg
= n_arg
- adjust
;
638 r
->u
.conversion
.from
= from
;
639 r
->u
.conversion
.to_type
= to
;
640 r
->u
.conversion
.loc
= loc
;
644 static struct rejection_reason
*
645 bad_arg_conversion_rejection (tree first_arg
, int n_arg
, tree from
, tree to
,
648 struct rejection_reason
*r
= alloc_rejection (rr_bad_arg_conversion
);
649 int adjust
= first_arg
!= NULL_TREE
;
650 r
->u
.bad_conversion
.n_arg
= n_arg
- adjust
;
651 r
->u
.bad_conversion
.from
= from
;
652 r
->u
.bad_conversion
.to_type
= to
;
653 r
->u
.bad_conversion
.loc
= loc
;
657 static struct rejection_reason
*
658 explicit_conversion_rejection (tree from
, tree to
)
660 struct rejection_reason
*r
= alloc_rejection (rr_explicit_conversion
);
661 r
->u
.conversion
.n_arg
= 0;
662 r
->u
.conversion
.from
= from
;
663 r
->u
.conversion
.to_type
= to
;
664 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
668 static struct rejection_reason
*
669 template_conversion_rejection (tree from
, tree to
)
671 struct rejection_reason
*r
= alloc_rejection (rr_template_conversion
);
672 r
->u
.conversion
.n_arg
= 0;
673 r
->u
.conversion
.from
= from
;
674 r
->u
.conversion
.to_type
= to
;
675 r
->u
.conversion
.loc
= UNKNOWN_LOCATION
;
679 static struct rejection_reason
*
680 template_unification_rejection (tree tmpl
, tree explicit_targs
, tree targs
,
681 const tree
*args
, unsigned int nargs
,
682 tree return_type
, unification_kind_t strict
,
685 size_t args_n_bytes
= sizeof (*args
) * nargs
;
686 tree
*args1
= (tree
*) conversion_obstack_alloc (args_n_bytes
);
687 struct rejection_reason
*r
= alloc_rejection (rr_template_unification
);
688 r
->u
.template_unification
.tmpl
= tmpl
;
689 r
->u
.template_unification
.explicit_targs
= explicit_targs
;
690 r
->u
.template_unification
.num_targs
= TREE_VEC_LENGTH (targs
);
691 /* Copy args to our own storage. */
692 memcpy (args1
, args
, args_n_bytes
);
693 r
->u
.template_unification
.args
= args1
;
694 r
->u
.template_unification
.nargs
= nargs
;
695 r
->u
.template_unification
.return_type
= return_type
;
696 r
->u
.template_unification
.strict
= strict
;
697 r
->u
.template_unification
.flags
= flags
;
701 static struct rejection_reason
*
702 template_unification_error_rejection (void)
704 return alloc_rejection (rr_template_unification
);
707 static struct rejection_reason
*
708 invalid_copy_with_fn_template_rejection (void)
710 struct rejection_reason
*r
= alloc_rejection (rr_invalid_copy
);
714 static struct rejection_reason
*
715 inherited_ctor_rejection (void)
717 struct rejection_reason
*r
= alloc_rejection (rr_inherited_ctor
);
721 // Build a constraint failure record, saving information into the
722 // template_instantiation field of the rejection. If FN is not a template
723 // declaration, the TMPL member is the FN declaration and TARGS is empty.
725 static struct rejection_reason
*
726 constraint_failure (tree fn
)
728 struct rejection_reason
*r
= alloc_rejection (rr_constraint_failure
);
729 if (tree ti
= DECL_TEMPLATE_INFO (fn
))
731 r
->u
.template_instantiation
.tmpl
= TI_TEMPLATE (ti
);
732 r
->u
.template_instantiation
.targs
= TI_ARGS (ti
);
736 r
->u
.template_instantiation
.tmpl
= fn
;
737 r
->u
.template_instantiation
.targs
= NULL_TREE
;
742 /* Dynamically allocate a conversion. */
745 alloc_conversion (conversion_kind kind
)
748 c
= (conversion
*) conversion_obstack_alloc (sizeof (conversion
));
753 /* Make sure that all memory on the conversion obstack has been
757 validate_conversion_obstack (void)
759 if (conversion_obstack_initialized
)
760 gcc_assert ((obstack_next_free (&conversion_obstack
)
761 == obstack_base (&conversion_obstack
)));
764 /* Dynamically allocate an array of N conversions. */
767 alloc_conversions (size_t n
)
769 return (conversion
**) conversion_obstack_alloc (n
* sizeof (conversion
*));
773 build_conv (conversion_kind code
, tree type
, conversion
*from
)
776 conversion_rank rank
= CONVERSION_RANK (from
);
778 /* Note that the caller is responsible for filling in t->cand for
779 user-defined conversions. */
780 t
= alloc_conversion (code
);
804 t
->user_conv_p
= (code
== ck_user
|| from
->user_conv_p
);
805 t
->bad_p
= from
->bad_p
;
810 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
811 specialization of std::initializer_list<T>, if such a conversion is
815 build_list_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
817 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type
), 0);
818 unsigned len
= CONSTRUCTOR_NELTS (ctor
);
819 conversion
**subconvs
= alloc_conversions (len
);
824 /* Within a list-initialization we can have more user-defined
826 flags
&= ~LOOKUP_NO_CONVERSION
;
827 /* But no narrowing conversions. */
828 flags
|= LOOKUP_NO_NARROWING
;
830 /* Can't make an array of these types. */
831 if (TYPE_REF_P (elttype
)
832 || TREE_CODE (elttype
) == FUNCTION_TYPE
833 || VOID_TYPE_P (elttype
))
836 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
839 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
840 false, flags
, complain
);
847 t
= alloc_conversion (ck_list
);
849 t
->u
.list
= subconvs
;
852 for (i
= 0; i
< len
; ++i
)
854 conversion
*sub
= subconvs
[i
];
855 if (sub
->rank
> t
->rank
)
857 if (sub
->user_conv_p
)
858 t
->user_conv_p
= true;
866 /* Return the next conversion of the conversion chain (if applicable),
867 or NULL otherwise. Please use this function instead of directly
868 accessing fields of struct conversion. */
871 next_conversion (conversion
*conv
)
874 || conv
->kind
== ck_identity
875 || conv
->kind
== ck_ambig
876 || conv
->kind
== ck_list
)
881 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
882 is a valid aggregate initializer for array type ATYPE. */
885 can_convert_array (tree atype
, tree ctor
, int flags
, tsubst_flags_t complain
)
888 tree elttype
= TREE_TYPE (atype
);
889 for (i
= 0; i
< CONSTRUCTOR_NELTS (ctor
); ++i
)
891 tree val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
893 if (TREE_CODE (elttype
) == ARRAY_TYPE
894 && TREE_CODE (val
) == CONSTRUCTOR
)
895 ok
= can_convert_array (elttype
, val
, flags
, complain
);
897 ok
= can_convert_arg (elttype
, TREE_TYPE (val
), val
, flags
,
905 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
906 aggregate class, if such a conversion is possible. */
909 build_aggr_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
911 unsigned HOST_WIDE_INT i
= 0;
913 tree field
= next_initializable_field (TYPE_FIELDS (type
));
914 tree empty_ctor
= NULL_TREE
;
916 /* We already called reshape_init in implicit_conversion. */
918 /* The conversions within the init-list aren't affected by the enclosing
919 context; they're always simple copy-initialization. */
920 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
922 for (; field
; field
= next_initializable_field (DECL_CHAIN (field
)))
924 tree ftype
= TREE_TYPE (field
);
928 if (i
< CONSTRUCTOR_NELTS (ctor
))
929 val
= CONSTRUCTOR_ELT (ctor
, i
)->value
;
930 else if (DECL_INITIAL (field
))
931 val
= get_nsdmi (field
, /*ctor*/false, complain
);
932 else if (TYPE_REF_P (ftype
))
933 /* Value-initialization of reference is ill-formed. */
937 if (empty_ctor
== NULL_TREE
)
938 empty_ctor
= build_constructor (init_list_type_node
, NULL
);
943 if (TREE_CODE (ftype
) == ARRAY_TYPE
944 && TREE_CODE (val
) == CONSTRUCTOR
)
945 ok
= can_convert_array (ftype
, val
, flags
, complain
);
947 ok
= can_convert_arg (ftype
, TREE_TYPE (val
), val
, flags
,
953 if (TREE_CODE (type
) == UNION_TYPE
)
957 if (i
< CONSTRUCTOR_NELTS (ctor
))
960 c
= alloc_conversion (ck_aggr
);
963 c
->user_conv_p
= true;
964 c
->check_narrowing
= true;
969 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
970 array type, if such a conversion is possible. */
973 build_array_conv (tree type
, tree ctor
, int flags
, tsubst_flags_t complain
)
976 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
977 tree elttype
= TREE_TYPE (type
);
982 enum conversion_rank rank
= cr_exact
;
984 /* We might need to propagate the size from the element to the array. */
985 complete_type (type
);
987 if (TYPE_DOMAIN (type
)
988 && !variably_modified_type_p (TYPE_DOMAIN (type
), NULL_TREE
))
990 unsigned HOST_WIDE_INT alen
= tree_to_uhwi (array_type_nelts_top (type
));
995 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
997 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1000 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1001 false, flags
, complain
);
1005 if (sub
->rank
> rank
)
1007 if (sub
->user_conv_p
)
1013 c
= alloc_conversion (ck_aggr
);
1016 c
->user_conv_p
= user
;
1022 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1023 complex type, if such a conversion is possible. */
1026 build_complex_conv (tree type
, tree ctor
, int flags
,
1027 tsubst_flags_t complain
)
1030 unsigned HOST_WIDE_INT len
= CONSTRUCTOR_NELTS (ctor
);
1031 tree elttype
= TREE_TYPE (type
);
1036 enum conversion_rank rank
= cr_exact
;
1041 flags
= LOOKUP_IMPLICIT
|LOOKUP_NO_NARROWING
;
1043 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor
), i
, val
)
1046 = implicit_conversion (elttype
, TREE_TYPE (val
), val
,
1047 false, flags
, complain
);
1051 if (sub
->rank
> rank
)
1053 if (sub
->user_conv_p
)
1059 c
= alloc_conversion (ck_aggr
);
1062 c
->user_conv_p
= user
;
1068 /* Build a representation of the identity conversion from EXPR to
1069 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1072 build_identity_conv (tree type
, tree expr
)
1076 c
= alloc_conversion (ck_identity
);
1083 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1084 were multiple user-defined conversions to accomplish the job.
1085 Build a conversion that indicates that ambiguity. */
1088 build_ambiguous_conv (tree type
, tree expr
)
1092 c
= alloc_conversion (ck_ambig
);
1100 strip_top_quals (tree t
)
1102 if (TREE_CODE (t
) == ARRAY_TYPE
)
1104 return cp_build_qualified_type (t
, 0);
1107 /* Returns the standard conversion path (see [conv]) from type FROM to type
1108 TO, if any. For proper handling of null pointer constants, you must
1109 also pass the expression EXPR to convert from. If C_CAST_P is true,
1110 this conversion is coming from a C-style cast. */
1113 standard_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1114 int flags
, tsubst_flags_t complain
)
1116 enum tree_code fcode
, tcode
;
1118 bool fromref
= false;
1121 to
= non_reference (to
);
1122 if (TYPE_REF_P (from
))
1125 from
= TREE_TYPE (from
);
1128 to
= strip_top_quals (to
);
1129 from
= strip_top_quals (from
);
1131 if (expr
&& type_unknown_p (expr
))
1133 if (TYPE_PTRFN_P (to
) || TYPE_PTRMEMFUNC_P (to
))
1135 tsubst_flags_t tflags
= tf_conv
;
1136 expr
= instantiate_type (to
, expr
, tflags
);
1137 if (expr
== error_mark_node
)
1139 from
= TREE_TYPE (expr
);
1141 else if (TREE_CODE (to
) == BOOLEAN_TYPE
)
1143 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1144 expr
= resolve_nondeduced_context (expr
, complain
);
1145 from
= TREE_TYPE (expr
);
1149 fcode
= TREE_CODE (from
);
1150 tcode
= TREE_CODE (to
);
1152 conv
= build_identity_conv (from
, expr
);
1153 if (fcode
== FUNCTION_TYPE
|| fcode
== ARRAY_TYPE
)
1155 from
= type_decays_to (from
);
1156 fcode
= TREE_CODE (from
);
1157 /* Tell convert_like_real that we're using the address. */
1158 conv
->rvaluedness_matches_p
= true;
1159 conv
= build_conv (ck_lvalue
, from
, conv
);
1161 /* Wrapping a ck_rvalue around a class prvalue (as a result of using
1162 obvalue_p) seems odd, since it's already a prvalue, but that's how we
1163 express the copy constructor call required by copy-initialization. */
1164 else if (fromref
|| (expr
&& obvalue_p (expr
)))
1169 bitfield_type
= is_bitfield_expr_with_lowered_type (expr
);
1172 from
= strip_top_quals (bitfield_type
);
1173 fcode
= TREE_CODE (from
);
1176 conv
= build_conv (ck_rvalue
, from
, conv
);
1177 if (flags
& LOOKUP_PREFER_RVALUE
)
1178 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1179 conv
->rvaluedness_matches_p
= true;
1182 /* Allow conversion between `__complex__' data types. */
1183 if (tcode
== COMPLEX_TYPE
&& fcode
== COMPLEX_TYPE
)
1185 /* The standard conversion sequence to convert FROM to TO is
1186 the standard conversion sequence to perform componentwise
1188 conversion
*part_conv
= standard_conversion
1189 (TREE_TYPE (to
), TREE_TYPE (from
), NULL_TREE
, c_cast_p
, flags
,
1194 conv
= build_conv (part_conv
->kind
, to
, conv
);
1195 conv
->rank
= part_conv
->rank
;
1203 if (same_type_p (from
, to
))
1205 if (CLASS_TYPE_P (to
) && conv
->kind
== ck_rvalue
)
1206 conv
->type
= qualified_to
;
1211 A null pointer constant can be converted to a pointer type; ... A
1212 null pointer constant of integral type can be converted to an
1213 rvalue of type std::nullptr_t. */
1214 if ((tcode
== POINTER_TYPE
|| TYPE_PTRMEM_P (to
)
1215 || NULLPTR_TYPE_P (to
))
1216 && ((expr
&& null_ptr_cst_p (expr
))
1217 || NULLPTR_TYPE_P (from
)))
1218 conv
= build_conv (ck_std
, to
, conv
);
1219 else if ((tcode
== INTEGER_TYPE
&& fcode
== POINTER_TYPE
)
1220 || (tcode
== POINTER_TYPE
&& fcode
== INTEGER_TYPE
))
1222 /* For backwards brain damage compatibility, allow interconversion of
1223 pointers and integers with a pedwarn. */
1224 conv
= build_conv (ck_std
, to
, conv
);
1227 else if (UNSCOPED_ENUM_P (to
) && fcode
== INTEGER_TYPE
)
1229 /* For backwards brain damage compatibility, allow interconversion of
1230 enums and integers with a pedwarn. */
1231 conv
= build_conv (ck_std
, to
, conv
);
1234 else if ((tcode
== POINTER_TYPE
&& fcode
== POINTER_TYPE
)
1235 || (TYPE_PTRDATAMEM_P (to
) && TYPE_PTRDATAMEM_P (from
)))
1240 if (tcode
== POINTER_TYPE
)
1242 to_pointee
= TREE_TYPE (to
);
1243 from_pointee
= TREE_TYPE (from
);
1245 /* Since this is the target of a pointer, it can't have function
1246 qualifiers, so any TYPE_QUALS must be for attributes const or
1247 noreturn. Strip them. */
1248 if (TREE_CODE (to_pointee
) == FUNCTION_TYPE
1249 && TYPE_QUALS (to_pointee
))
1250 to_pointee
= build_qualified_type (to_pointee
, TYPE_UNQUALIFIED
);
1251 if (TREE_CODE (from_pointee
) == FUNCTION_TYPE
1252 && TYPE_QUALS (from_pointee
))
1253 from_pointee
= build_qualified_type (from_pointee
, TYPE_UNQUALIFIED
);
1257 to_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (to
);
1258 from_pointee
= TYPE_PTRMEM_POINTED_TO_TYPE (from
);
1261 if (tcode
== POINTER_TYPE
1262 && same_type_ignoring_top_level_qualifiers_p (from_pointee
,
1265 else if (VOID_TYPE_P (to_pointee
)
1266 && !TYPE_PTRDATAMEM_P (from
)
1267 && TREE_CODE (from_pointee
) != FUNCTION_TYPE
)
1269 tree nfrom
= TREE_TYPE (from
);
1270 /* Don't try to apply restrict to void. */
1271 int quals
= cp_type_quals (nfrom
) & ~TYPE_QUAL_RESTRICT
;
1272 from_pointee
= cp_build_qualified_type (void_type_node
, quals
);
1273 from
= build_pointer_type (from_pointee
);
1274 conv
= build_conv (ck_ptr
, from
, conv
);
1276 else if (TYPE_PTRDATAMEM_P (from
))
1278 tree fbase
= TYPE_PTRMEM_CLASS_TYPE (from
);
1279 tree tbase
= TYPE_PTRMEM_CLASS_TYPE (to
);
1281 if (same_type_p (fbase
, tbase
))
1282 /* No base conversion needed. */;
1283 else if (DERIVED_FROM_P (fbase
, tbase
)
1284 && (same_type_ignoring_top_level_qualifiers_p
1285 (from_pointee
, to_pointee
)))
1287 from
= build_ptrmem_type (tbase
, from_pointee
);
1288 conv
= build_conv (ck_pmem
, from
, conv
);
1293 else if (CLASS_TYPE_P (from_pointee
)
1294 && CLASS_TYPE_P (to_pointee
)
1297 An rvalue of type "pointer to cv D," where D is a
1298 class type, can be converted to an rvalue of type
1299 "pointer to cv B," where B is a base class (clause
1300 _class.derived_) of D. If B is an inaccessible
1301 (clause _class.access_) or ambiguous
1302 (_class.member.lookup_) base class of D, a program
1303 that necessitates this conversion is ill-formed.
1304 Therefore, we use DERIVED_FROM_P, and do not check
1305 access or uniqueness. */
1306 && DERIVED_FROM_P (to_pointee
, from_pointee
))
1309 = cp_build_qualified_type (to_pointee
,
1310 cp_type_quals (from_pointee
));
1311 from
= build_pointer_type (from_pointee
);
1312 conv
= build_conv (ck_ptr
, from
, conv
);
1313 conv
->base_p
= true;
1316 if (same_type_p (from
, to
))
1318 else if (c_cast_p
&& comp_ptr_ttypes_const (to
, from
))
1319 /* In a C-style cast, we ignore CV-qualification because we
1320 are allowed to perform a static_cast followed by a
1322 conv
= build_conv (ck_qual
, to
, conv
);
1323 else if (!c_cast_p
&& comp_ptr_ttypes (to_pointee
, from_pointee
))
1324 conv
= build_conv (ck_qual
, to
, conv
);
1325 else if (expr
&& string_conv_p (to
, expr
, 0))
1326 /* converting from string constant to char *. */
1327 conv
= build_conv (ck_qual
, to
, conv
);
1328 else if (fnptr_conv_p (to
, from
))
1329 conv
= build_conv (ck_fnptr
, to
, conv
);
1330 /* Allow conversions among compatible ObjC pointer types (base
1331 conversions have been already handled above). */
1332 else if (c_dialect_objc ()
1333 && objc_compare_types (to
, from
, -4, NULL_TREE
))
1334 conv
= build_conv (ck_ptr
, to
, conv
);
1335 else if (ptr_reasonably_similar (to_pointee
, from_pointee
))
1337 conv
= build_conv (ck_ptr
, to
, conv
);
1345 else if (TYPE_PTRMEMFUNC_P (to
) && TYPE_PTRMEMFUNC_P (from
))
1347 tree fromfn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from
));
1348 tree tofn
= TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to
));
1349 tree fbase
= class_of_this_parm (fromfn
);
1350 tree tbase
= class_of_this_parm (tofn
);
1352 if (!DERIVED_FROM_P (fbase
, tbase
))
1355 tree fstat
= static_fn_type (fromfn
);
1356 tree tstat
= static_fn_type (tofn
);
1357 if (same_type_p (tstat
, fstat
)
1358 || fnptr_conv_p (tstat
, fstat
))
1363 if (!same_type_p (fbase
, tbase
))
1365 from
= build_memfn_type (fstat
,
1367 cp_type_quals (tbase
),
1368 type_memfn_rqual (tofn
));
1369 from
= build_ptrmemfunc_type (build_pointer_type (from
));
1370 conv
= build_conv (ck_pmem
, from
, conv
);
1371 conv
->base_p
= true;
1373 if (fnptr_conv_p (tstat
, fstat
))
1374 conv
= build_conv (ck_fnptr
, to
, conv
);
1376 else if (tcode
== BOOLEAN_TYPE
)
1380 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1381 to member type can be converted to a prvalue of type bool. ...
1382 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1383 std::nullptr_t can be converted to a prvalue of type bool; */
1384 if (ARITHMETIC_TYPE_P (from
)
1385 || UNSCOPED_ENUM_P (from
)
1386 || fcode
== POINTER_TYPE
1387 || TYPE_PTRMEM_P (from
)
1388 || NULLPTR_TYPE_P (from
))
1390 conv
= build_conv (ck_std
, to
, conv
);
1391 if (fcode
== POINTER_TYPE
1392 || TYPE_PTRDATAMEM_P (from
)
1393 || (TYPE_PTRMEMFUNC_P (from
)
1394 && conv
->rank
< cr_pbool
)
1395 || NULLPTR_TYPE_P (from
))
1396 conv
->rank
= cr_pbool
;
1397 if (NULLPTR_TYPE_P (from
) && (flags
& LOOKUP_ONLYCONVERTING
))
1399 if (flags
& LOOKUP_NO_NARROWING
)
1400 conv
->check_narrowing
= true;
1406 /* We don't check for ENUMERAL_TYPE here because there are no standard
1407 conversions to enum type. */
1408 /* As an extension, allow conversion to complex type. */
1409 else if (ARITHMETIC_TYPE_P (to
))
1411 if (! (INTEGRAL_CODE_P (fcode
)
1412 || (fcode
== REAL_TYPE
&& !(flags
& LOOKUP_NO_NON_INTEGRAL
)))
1413 || SCOPED_ENUM_P (from
))
1415 conv
= build_conv (ck_std
, to
, conv
);
1417 /* Give this a better rank if it's a promotion. */
1418 if (same_type_p (to
, type_promotes_to (from
))
1419 && next_conversion (conv
)->rank
<= cr_promotion
)
1420 conv
->rank
= cr_promotion
;
1422 else if (fcode
== VECTOR_TYPE
&& tcode
== VECTOR_TYPE
1423 && vector_types_convertible_p (from
, to
, false))
1424 return build_conv (ck_std
, to
, conv
);
1425 else if (MAYBE_CLASS_TYPE_P (to
) && MAYBE_CLASS_TYPE_P (from
)
1426 && is_properly_derived_from (from
, to
))
1428 if (conv
->kind
== ck_rvalue
)
1429 conv
= next_conversion (conv
);
1430 conv
= build_conv (ck_base
, to
, conv
);
1431 /* The derived-to-base conversion indicates the initialization
1432 of a parameter with base type from an object of a derived
1433 type. A temporary object is created to hold the result of
1434 the conversion unless we're binding directly to a reference. */
1435 conv
->need_temporary_p
= !(flags
& LOOKUP_NO_TEMP_BIND
);
1436 if (flags
& LOOKUP_PREFER_RVALUE
)
1437 /* Tell convert_like_real to set LOOKUP_PREFER_RVALUE. */
1438 conv
->rvaluedness_matches_p
= true;
1443 if (flags
& LOOKUP_NO_NARROWING
)
1444 conv
->check_narrowing
= true;
1449 /* Returns nonzero if T1 is reference-related to T2. */
1452 reference_related_p (tree t1
, tree t2
)
1454 if (t1
== error_mark_node
|| t2
== error_mark_node
)
1457 t1
= TYPE_MAIN_VARIANT (t1
);
1458 t2
= TYPE_MAIN_VARIANT (t2
);
1462 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1463 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1465 return (same_type_p (t1
, t2
)
1466 || (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
1467 && DERIVED_FROM_P (t1
, t2
)));
1470 /* Returns nonzero if T1 is reference-compatible with T2. */
1473 reference_compatible_p (tree t1
, tree t2
)
1477 "cv1 T1" is reference compatible with "cv2 T2" if
1478 * T1 is reference-related to T2 or
1479 * T2 is "noexcept function" and T1 is "function", where the
1480 function types are otherwise the same,
1481 and cv1 is the same cv-qualification as, or greater cv-qualification
1483 return ((reference_related_p (t1
, t2
)
1484 || fnptr_conv_p (t1
, t2
))
1485 && at_least_as_qualified_p (t1
, t2
));
1488 /* A reference of the indicated TYPE is being bound directly to the
1489 expression represented by the implicit conversion sequence CONV.
1490 Return a conversion sequence for this binding. */
1493 direct_reference_binding (tree type
, conversion
*conv
)
1497 gcc_assert (TYPE_REF_P (type
));
1498 gcc_assert (!TYPE_REF_P (conv
->type
));
1500 t
= TREE_TYPE (type
);
1502 if (conv
->kind
== ck_identity
)
1503 /* Mark the identity conv as to not decay to rvalue. */
1504 conv
->rvaluedness_matches_p
= true;
1508 When a parameter of reference type binds directly
1509 (_dcl.init.ref_) to an argument expression, the implicit
1510 conversion sequence is the identity conversion, unless the
1511 argument expression has a type that is a derived class of the
1512 parameter type, in which case the implicit conversion sequence is
1513 a derived-to-base Conversion.
1515 If the parameter binds directly to the result of applying a
1516 conversion function to the argument expression, the implicit
1517 conversion sequence is a user-defined conversion sequence
1518 (_over.ics.user_), with the second standard conversion sequence
1519 either an identity conversion or, if the conversion function
1520 returns an entity of a type that is a derived class of the
1521 parameter type, a derived-to-base conversion. */
1522 if (is_properly_derived_from (conv
->type
, t
))
1524 /* Represent the derived-to-base conversion. */
1525 conv
= build_conv (ck_base
, t
, conv
);
1526 /* We will actually be binding to the base-class subobject in
1527 the derived class, so we mark this conversion appropriately.
1528 That way, convert_like knows not to generate a temporary. */
1529 conv
->need_temporary_p
= false;
1532 return build_conv (ck_ref_bind
, type
, conv
);
1535 /* Returns the conversion path from type FROM to reference type TO for
1536 purposes of reference binding. For lvalue binding, either pass a
1537 reference type to FROM or an lvalue expression to EXPR. If the
1538 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1539 the conversion returned. If C_CAST_P is true, this
1540 conversion is coming from a C-style cast. */
1543 reference_binding (tree rto
, tree rfrom
, tree expr
, bool c_cast_p
, int flags
,
1544 tsubst_flags_t complain
)
1546 conversion
*conv
= NULL
;
1547 tree to
= TREE_TYPE (rto
);
1552 cp_lvalue_kind gl_kind
;
1555 if (TREE_CODE (to
) == FUNCTION_TYPE
&& expr
&& type_unknown_p (expr
))
1557 expr
= instantiate_type (to
, expr
, tf_none
);
1558 if (expr
== error_mark_node
)
1560 from
= TREE_TYPE (expr
);
1563 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1565 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS
);
1566 /* DR 1288: Otherwise, if the initializer list has a single element
1567 of type E and ... [T's] referenced type is reference-related to E,
1568 the object or reference is initialized from that element... */
1569 if (CONSTRUCTOR_NELTS (expr
) == 1)
1571 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1572 if (error_operand_p (elt
))
1574 tree etype
= TREE_TYPE (elt
);
1575 if (reference_related_p (to
, etype
))
1582 /* Otherwise, if T is a reference type, a prvalue temporary of the type
1583 referenced by T is copy-list-initialized, and the reference is bound
1584 to that temporary. */
1585 CONSTRUCTOR_IS_DIRECT_INIT (expr
) = false;
1589 if (TYPE_REF_P (from
))
1591 from
= TREE_TYPE (from
);
1592 if (!TYPE_REF_IS_RVALUE (rfrom
)
1593 || TREE_CODE (from
) == FUNCTION_TYPE
)
1594 gl_kind
= clk_ordinary
;
1596 gl_kind
= clk_rvalueref
;
1599 gl_kind
= lvalue_kind (expr
);
1600 else if (CLASS_TYPE_P (from
)
1601 || TREE_CODE (from
) == ARRAY_TYPE
)
1602 gl_kind
= clk_class
;
1606 /* Don't allow a class prvalue when LOOKUP_NO_TEMP_BIND. */
1607 if ((flags
& LOOKUP_NO_TEMP_BIND
)
1608 && (gl_kind
& clk_class
))
1611 /* Same mask as real_lvalue_p. */
1612 is_lvalue
= gl_kind
&& !(gl_kind
& (clk_rvalueref
|clk_class
));
1615 if ((gl_kind
& clk_bitfield
) != 0)
1616 tfrom
= unlowered_expr_type (expr
);
1618 /* Figure out whether or not the types are reference-related and
1619 reference compatible. We have to do this after stripping
1620 references from FROM. */
1621 related_p
= reference_related_p (to
, tfrom
);
1622 /* If this is a C cast, first convert to an appropriately qualified
1623 type, so that we can later do a const_cast to the desired type. */
1624 if (related_p
&& c_cast_p
1625 && !at_least_as_qualified_p (to
, tfrom
))
1626 to
= cp_build_qualified_type (to
, cp_type_quals (tfrom
));
1627 compatible_p
= reference_compatible_p (to
, tfrom
);
1629 /* Directly bind reference when target expression's type is compatible with
1630 the reference and expression is an lvalue. In DR391, the wording in
1631 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1632 const and rvalue references to rvalues of compatible class type.
1633 We should also do direct bindings for non-class xvalues. */
1634 if ((related_p
|| compatible_p
) && gl_kind
)
1638 If the initializer expression
1640 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1641 is reference-compatible with "cv2 T2,"
1643 the reference is bound directly to the initializer expression
1647 If the initializer expression is an rvalue, with T2 a class type,
1648 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1649 is bound to the object represented by the rvalue or to a sub-object
1650 within that object. */
1652 conv
= build_identity_conv (tfrom
, expr
);
1653 conv
= direct_reference_binding (rto
, conv
);
1655 if (TYPE_REF_P (rfrom
))
1656 /* Handle rvalue reference to function properly. */
1657 conv
->rvaluedness_matches_p
1658 = (TYPE_REF_IS_RVALUE (rto
) == TYPE_REF_IS_RVALUE (rfrom
));
1660 conv
->rvaluedness_matches_p
1661 = (TYPE_REF_IS_RVALUE (rto
) == !is_lvalue
);
1663 if ((gl_kind
& clk_bitfield
) != 0
1664 || ((gl_kind
& clk_packed
) != 0 && !TYPE_PACKED (to
)))
1665 /* For the purposes of overload resolution, we ignore the fact
1666 this expression is a bitfield or packed field. (In particular,
1667 [over.ics.ref] says specifically that a function with a
1668 non-const reference parameter is viable even if the
1669 argument is a bitfield.)
1671 However, when we actually call the function we must create
1672 a temporary to which to bind the reference. If the
1673 reference is volatile, or isn't const, then we cannot make
1674 a temporary, so we just issue an error when the conversion
1676 conv
->need_temporary_p
= true;
1678 /* Don't allow binding of lvalues (other than function lvalues) to
1679 rvalue references. */
1680 if (is_lvalue
&& TYPE_REF_IS_RVALUE (rto
)
1681 && TREE_CODE (to
) != FUNCTION_TYPE
)
1684 /* Nor the reverse. */
1685 if (!is_lvalue
&& !TYPE_REF_IS_RVALUE (rto
)
1686 && (!CP_TYPE_CONST_NON_VOLATILE_P (to
)
1687 || (flags
& LOOKUP_NO_RVAL_BIND
))
1688 && TREE_CODE (to
) != FUNCTION_TYPE
)
1696 /* [class.conv.fct] A conversion function is never used to convert a
1697 (possibly cv-qualified) object to the (possibly cv-qualified) same
1698 object type (or a reference to it), to a (possibly cv-qualified) base
1699 class of that type (or a reference to it).... */
1700 else if (CLASS_TYPE_P (from
) && !related_p
1701 && !(flags
& LOOKUP_NO_CONVERSION
))
1705 If the initializer expression
1707 -- has a class type (i.e., T2 is a class type) can be
1708 implicitly converted to an lvalue of type "cv3 T3," where
1709 "cv1 T1" is reference-compatible with "cv3 T3". (this
1710 conversion is selected by enumerating the applicable
1711 conversion functions (_over.match.ref_) and choosing the
1712 best one through overload resolution. (_over.match_).
1714 the reference is bound to the lvalue result of the conversion
1715 in the second case. */
1716 z_candidate
*cand
= build_user_type_conversion_1 (rto
, expr
, flags
,
1719 return cand
->second_conv
;
1722 /* From this point on, we conceptually need temporaries, even if we
1723 elide them. Only the cases above are "direct bindings". */
1724 if (flags
& LOOKUP_NO_TEMP_BIND
)
1729 When a parameter of reference type is not bound directly to an
1730 argument expression, the conversion sequence is the one required
1731 to convert the argument expression to the underlying type of the
1732 reference according to _over.best.ics_. Conceptually, this
1733 conversion sequence corresponds to copy-initializing a temporary
1734 of the underlying type with the argument expression. Any
1735 difference in top-level cv-qualification is subsumed by the
1736 initialization itself and does not constitute a conversion. */
1740 Otherwise, the reference shall be an lvalue reference to a
1741 non-volatile const type, or the reference shall be an rvalue
1744 We try below to treat this as a bad conversion to improve diagnostics,
1745 but if TO is an incomplete class, we need to reject this conversion
1746 now to avoid unnecessary instantiation. */
1747 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
)
1748 && !COMPLETE_TYPE_P (to
))
1751 /* We're generating a temporary now, but don't bind any more in the
1752 conversion (specifically, don't slice the temporary returned by a
1753 conversion operator). */
1754 flags
|= LOOKUP_NO_TEMP_BIND
;
1756 /* Core issue 899: When [copy-]initializing a temporary to be bound
1757 to the first parameter of a copy constructor (12.8) called with
1758 a single argument in the context of direct-initialization,
1759 explicit conversion functions are also considered.
1761 So don't set LOOKUP_ONLYCONVERTING in that case. */
1762 if (!(flags
& LOOKUP_COPY_PARM
))
1763 flags
|= LOOKUP_ONLYCONVERTING
;
1766 conv
= implicit_conversion (to
, from
, expr
, c_cast_p
,
1771 if (conv
->user_conv_p
)
1773 /* If initializing the temporary used a conversion function,
1774 recalculate the second conversion sequence. */
1775 for (conversion
*t
= conv
; t
; t
= next_conversion (t
))
1776 if (t
->kind
== ck_user
1777 && DECL_CONV_FN_P (t
->cand
->fn
))
1779 tree ftype
= TREE_TYPE (TREE_TYPE (t
->cand
->fn
));
1780 int sflags
= (flags
|LOOKUP_NO_CONVERSION
)&~LOOKUP_NO_TEMP_BIND
;
1781 conversion
*new_second
1782 = reference_binding (rto
, ftype
, NULL_TREE
, c_cast_p
,
1786 return merge_conversion_sequences (t
, new_second
);
1790 conv
= build_conv (ck_ref_bind
, rto
, conv
);
1791 /* This reference binding, unlike those above, requires the
1792 creation of a temporary. */
1793 conv
->need_temporary_p
= true;
1794 conv
->rvaluedness_matches_p
= TYPE_REF_IS_RVALUE (rto
);
1798 Otherwise, the reference shall be an lvalue reference to a
1799 non-volatile const type, or the reference shall be an rvalue
1801 if (!CP_TYPE_CONST_NON_VOLATILE_P (to
) && !TYPE_REF_IS_RVALUE (rto
))
1806 Otherwise, a temporary of type "cv1 T1" is created and
1807 initialized from the initializer expression using the rules for a
1808 non-reference copy initialization. If T1 is reference-related to
1809 T2, cv1 must be the same cv-qualification as, or greater
1810 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1811 if (related_p
&& !at_least_as_qualified_p (to
, from
))
1817 /* Returns the implicit conversion sequence (see [over.ics]) from type
1818 FROM to type TO. The optional expression EXPR may affect the
1819 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1820 true, this conversion is coming from a C-style cast. */
1823 implicit_conversion (tree to
, tree from
, tree expr
, bool c_cast_p
,
1824 int flags
, tsubst_flags_t complain
)
1828 if (from
== error_mark_node
|| to
== error_mark_node
1829 || expr
== error_mark_node
)
1832 /* Other flags only apply to the primary function in overload
1833 resolution, or after we've chosen one. */
1834 flags
&= (LOOKUP_ONLYCONVERTING
|LOOKUP_NO_CONVERSION
|LOOKUP_COPY_PARM
1835 |LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
|LOOKUP_PREFER_RVALUE
1836 |LOOKUP_NO_NARROWING
|LOOKUP_PROTECT
|LOOKUP_NO_NON_INTEGRAL
);
1838 /* FIXME: actually we don't want warnings either, but we can't just
1839 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1840 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1841 We really ought not to issue that warning until we've committed
1842 to that conversion. */
1843 complain
&= ~tf_error
;
1845 /* Call reshape_init early to remove redundant braces. */
1846 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
)
1847 && CLASS_TYPE_P (to
)
1848 && COMPLETE_TYPE_P (complete_type (to
))
1849 && !CLASSTYPE_NON_AGGREGATE (to
))
1851 expr
= reshape_init (to
, expr
, complain
);
1852 if (expr
== error_mark_node
)
1854 from
= TREE_TYPE (expr
);
1857 if (TYPE_REF_P (to
))
1858 conv
= reference_binding (to
, from
, expr
, c_cast_p
, flags
, complain
);
1860 conv
= standard_conversion (to
, from
, expr
, c_cast_p
, flags
, complain
);
1865 if (expr
&& BRACE_ENCLOSED_INITIALIZER_P (expr
))
1867 if (is_std_init_list (to
))
1868 return build_list_conv (to
, expr
, flags
, complain
);
1870 /* As an extension, allow list-initialization of _Complex. */
1871 if (TREE_CODE (to
) == COMPLEX_TYPE
)
1873 conv
= build_complex_conv (to
, expr
, flags
, complain
);
1878 /* Allow conversion from an initializer-list with one element to a
1880 if (SCALAR_TYPE_P (to
))
1882 int nelts
= CONSTRUCTOR_NELTS (expr
);
1886 elt
= build_value_init (to
, tf_none
);
1887 else if (nelts
== 1)
1888 elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1890 elt
= error_mark_node
;
1892 conv
= implicit_conversion (to
, TREE_TYPE (elt
), elt
,
1893 c_cast_p
, flags
, complain
);
1896 conv
->check_narrowing
= true;
1897 if (BRACE_ENCLOSED_INITIALIZER_P (elt
))
1898 /* Too many levels of braces, i.e. '{{1}}'. */
1903 else if (TREE_CODE (to
) == ARRAY_TYPE
)
1904 return build_array_conv (to
, expr
, flags
, complain
);
1907 if (expr
!= NULL_TREE
1908 && (MAYBE_CLASS_TYPE_P (from
)
1909 || MAYBE_CLASS_TYPE_P (to
))
1910 && (flags
& LOOKUP_NO_CONVERSION
) == 0)
1912 struct z_candidate
*cand
;
1914 if (CLASS_TYPE_P (to
)
1915 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
1916 && !CLASSTYPE_NON_AGGREGATE (complete_type (to
)))
1917 return build_aggr_conv (to
, expr
, flags
, complain
);
1919 cand
= build_user_type_conversion_1 (to
, expr
, flags
, complain
);
1922 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
1923 && CONSTRUCTOR_NELTS (expr
) == 1
1924 && !is_list_ctor (cand
->fn
))
1926 /* "If C is not an initializer-list constructor and the
1927 initializer list has a single element of type cv U, where U is
1928 X or a class derived from X, the implicit conversion sequence
1929 has Exact Match rank if U is X, or Conversion rank if U is
1931 tree elt
= CONSTRUCTOR_ELT (expr
, 0)->value
;
1932 tree elttype
= TREE_TYPE (elt
);
1933 if (reference_related_p (to
, elttype
))
1934 return implicit_conversion (to
, elttype
, elt
,
1935 c_cast_p
, flags
, complain
);
1937 conv
= cand
->second_conv
;
1940 /* We used to try to bind a reference to a temporary here, but that
1941 is now handled after the recursive call to this function at the end
1942 of reference_binding. */
1949 /* Like implicit_conversion, but return NULL if the conversion is bad.
1951 This is not static so that check_non_deducible_conversion can call it within
1952 add_template_candidate_real as part of overload resolution; it should not be
1953 called outside of overload resolution. */
1956 good_conversion (tree to
, tree from
, tree expr
,
1957 int flags
, tsubst_flags_t complain
)
1959 conversion
*c
= implicit_conversion (to
, from
, expr
, /*cast*/false,
1966 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1967 functions. ARGS will not be changed until a single candidate is
1970 static struct z_candidate
*
1971 add_candidate (struct z_candidate
**candidates
,
1972 tree fn
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
1973 size_t num_convs
, conversion
**convs
,
1974 tree access_path
, tree conversion_path
,
1975 int viable
, struct rejection_reason
*reason
,
1978 struct z_candidate
*cand
= (struct z_candidate
*)
1979 conversion_obstack_alloc (sizeof (struct z_candidate
));
1982 cand
->first_arg
= first_arg
;
1984 cand
->convs
= convs
;
1985 cand
->num_convs
= num_convs
;
1986 cand
->access_path
= access_path
;
1987 cand
->conversion_path
= conversion_path
;
1988 cand
->viable
= viable
;
1989 cand
->reason
= reason
;
1990 cand
->next
= *candidates
;
1991 cand
->flags
= flags
;
1997 /* Return the number of remaining arguments in the parameter list
1998 beginning with ARG. */
2001 remaining_arguments (tree arg
)
2005 for (n
= 0; arg
!= NULL_TREE
&& arg
!= void_list_node
;
2006 arg
= TREE_CHAIN (arg
))
2012 /* [over.match.copy]: When initializing a temporary object (12.2) to be bound
2013 to the first parameter of a constructor where the parameter is of type
2014 "reference to possibly cv-qualified T" and the constructor is called with a
2015 single argument in the context of direct-initialization of an object of type
2016 "cv2 T", explicit conversion functions are also considered.
2018 So set LOOKUP_COPY_PARM to let reference_binding know that
2019 it's being called in that context. */
2022 conv_flags (int i
, int nargs
, tree fn
, tree arg
, int flags
)
2026 if (i
== 0 && nargs
== 1 && DECL_CONSTRUCTOR_P (fn
)
2027 && (t
= FUNCTION_FIRST_USER_PARMTYPE (fn
))
2028 && (same_type_ignoring_top_level_qualifiers_p
2029 (non_reference (TREE_VALUE (t
)), DECL_CONTEXT (fn
))))
2031 if (!(flags
& LOOKUP_ONLYCONVERTING
))
2032 lflags
|= LOOKUP_COPY_PARM
;
2033 if ((flags
& LOOKUP_LIST_INIT_CTOR
)
2034 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
2035 lflags
|= LOOKUP_NO_CONVERSION
;
2038 lflags
|= LOOKUP_ONLYCONVERTING
;
2043 /* Create an overload candidate for the function or method FN called
2044 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
2045 FLAGS is passed on to implicit_conversion.
2047 This does not change ARGS.
2049 CTYPE, if non-NULL, is the type we want to pretend this function
2050 comes from for purposes of overload resolution. */
2052 static struct z_candidate
*
2053 add_function_candidate (struct z_candidate
**candidates
,
2054 tree fn
, tree ctype
, tree first_arg
,
2055 const vec
<tree
, va_gc
> *args
, tree access_path
,
2056 tree conversion_path
, int flags
,
2058 tsubst_flags_t complain
)
2060 tree parmlist
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2063 tree orig_first_arg
= first_arg
;
2066 struct rejection_reason
*reason
= NULL
;
2068 /* At this point we should not see any functions which haven't been
2069 explicitly declared, except for friend functions which will have
2070 been found using argument dependent lookup. */
2071 gcc_assert (!DECL_ANTICIPATED (fn
) || DECL_HIDDEN_FRIEND_P (fn
));
2073 /* The `this', `in_chrg' and VTT arguments to constructors are not
2074 considered in overload resolution. */
2075 if (DECL_CONSTRUCTOR_P (fn
))
2077 if (ctor_omit_inherited_parms (fn
))
2078 /* Bring back parameters omitted from an inherited ctor. */
2079 parmlist
= FUNCTION_FIRST_USER_PARMTYPE (DECL_ORIGIN (fn
));
2081 parmlist
= skip_artificial_parms_for (fn
, parmlist
);
2082 skip
= num_artificial_parms_for (fn
);
2083 if (skip
> 0 && first_arg
!= NULL_TREE
)
2086 first_arg
= NULL_TREE
;
2092 len
= vec_safe_length (args
) - skip
+ (first_arg
!= NULL_TREE
? 1 : 0);
2094 convs
= alloc_conversions (len
);
2096 /* 13.3.2 - Viable functions [over.match.viable]
2097 First, to be a viable function, a candidate function shall have enough
2098 parameters to agree in number with the arguments in the list.
2100 We need to check this first; otherwise, checking the ICSes might cause
2101 us to produce an ill-formed template instantiation. */
2103 parmnode
= parmlist
;
2104 for (i
= 0; i
< len
; ++i
)
2106 if (parmnode
== NULL_TREE
|| parmnode
== void_list_node
)
2108 parmnode
= TREE_CHAIN (parmnode
);
2111 if ((i
< len
&& parmnode
)
2112 || !sufficient_parms_p (parmnode
))
2114 int remaining
= remaining_arguments (parmnode
);
2116 reason
= arity_rejection (first_arg
, i
+ remaining
, len
);
2119 /* An inherited constructor (12.6.3 [class.inhctor.init]) that has a first
2120 parameter of type "reference to cv C" (including such a constructor
2121 instantiated from a template) is excluded from the set of candidate
2122 functions when used to construct an object of type D with an argument list
2123 containing a single argument if C is reference-related to D. */
2124 if (viable
&& len
== 1 && parmlist
&& DECL_CONSTRUCTOR_P (fn
)
2125 && flag_new_inheriting_ctors
2126 && DECL_INHERITED_CTOR (fn
))
2128 tree ptype
= non_reference (TREE_VALUE (parmlist
));
2129 tree dtype
= DECL_CONTEXT (fn
);
2130 tree btype
= DECL_INHERITED_CTOR_BASE (fn
);
2131 if (reference_related_p (ptype
, dtype
)
2132 && reference_related_p (btype
, ptype
))
2135 reason
= inherited_ctor_rejection ();
2139 /* Second, for a function to be viable, its constraints must be
2141 if (flag_concepts
&& viable
2142 && !constraints_satisfied_p (fn
))
2144 reason
= constraint_failure (fn
);
2148 /* When looking for a function from a subobject from an implicit
2149 copy/move constructor/operator=, don't consider anything that takes (a
2150 reference to) an unrelated type. See c++/44909 and core 1092. */
2151 if (viable
&& parmlist
&& (flags
& LOOKUP_DEFAULTED
))
2153 if (DECL_CONSTRUCTOR_P (fn
))
2155 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
2156 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
))
2162 parmnode
= chain_index (i
-1, parmlist
);
2163 if (!reference_related_p (non_reference (TREE_VALUE (parmnode
)),
2168 /* This only applies at the top level. */
2169 flags
&= ~LOOKUP_DEFAULTED
;
2175 /* Third, for F to be a viable function, there shall exist for each
2176 argument an implicit conversion sequence that converts that argument
2177 to the corresponding parameter of F. */
2179 parmnode
= parmlist
;
2181 for (i
= 0; i
< len
; ++i
)
2183 tree argtype
, to_type
;
2188 if (parmnode
== void_list_node
)
2193 /* Already set during deduction. */
2194 parmnode
= TREE_CHAIN (parmnode
);
2198 if (i
== 0 && first_arg
!= NULL_TREE
)
2201 arg
= CONST_CAST_TREE (
2202 (*args
)[i
+ skip
- (first_arg
!= NULL_TREE
? 1 : 0)]);
2203 argtype
= lvalue_type (arg
);
2205 is_this
= (i
== 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
)
2206 && ! DECL_CONSTRUCTOR_P (fn
));
2210 tree parmtype
= TREE_VALUE (parmnode
);
2212 parmnode
= TREE_CHAIN (parmnode
);
2214 /* The type of the implicit object parameter ('this') for
2215 overload resolution is not always the same as for the
2216 function itself; conversion functions are considered to
2217 be members of the class being converted, and functions
2218 introduced by a using-declaration are considered to be
2219 members of the class that uses them.
2221 Since build_over_call ignores the ICS for the `this'
2222 parameter, we can just change the parm type. */
2223 if (ctype
&& is_this
)
2225 parmtype
= cp_build_qualified_type
2226 (ctype
, cp_type_quals (TREE_TYPE (parmtype
)));
2227 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn
)))
2229 /* If the function has a ref-qualifier, the implicit
2230 object parameter has reference type. */
2231 bool rv
= FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn
));
2232 parmtype
= cp_build_reference_type (parmtype
, rv
);
2233 /* The special handling of 'this' conversions in compare_ics
2234 does not apply if there is a ref-qualifier. */
2239 parmtype
= build_pointer_type (parmtype
);
2240 /* We don't use build_this here because we don't want to
2241 capture the object argument until we've chosen a
2242 non-static member function. */
2243 arg
= build_address (arg
);
2244 argtype
= lvalue_type (arg
);
2248 int lflags
= conv_flags (i
, len
-skip
, fn
, arg
, flags
);
2250 t
= implicit_conversion (parmtype
, argtype
, arg
,
2251 /*c_cast_p=*/false, lflags
, complain
);
2256 t
= build_identity_conv (argtype
, arg
);
2257 t
->ellipsis_p
= true;
2268 reason
= arg_conversion_rejection (first_arg
, i
, argtype
, to_type
,
2269 EXPR_LOCATION (arg
));
2276 reason
= bad_arg_conversion_rejection (first_arg
, i
, arg
, to_type
,
2277 EXPR_LOCATION (arg
));
2283 return add_candidate (candidates
, fn
, orig_first_arg
, args
, len
, convs
,
2284 access_path
, conversion_path
, viable
, reason
, flags
);
2287 /* Create an overload candidate for the conversion function FN which will
2288 be invoked for expression OBJ, producing a pointer-to-function which
2289 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2290 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2291 passed on to implicit_conversion.
2293 Actually, we don't really care about FN; we care about the type it
2294 converts to. There may be multiple conversion functions that will
2295 convert to that type, and we rely on build_user_type_conversion_1 to
2296 choose the best one; so when we create our candidate, we record the type
2297 instead of the function. */
2299 static struct z_candidate
*
2300 add_conv_candidate (struct z_candidate
**candidates
, tree fn
, tree obj
,
2301 const vec
<tree
, va_gc
> *arglist
,
2302 tree access_path
, tree conversion_path
,
2303 tsubst_flags_t complain
)
2305 tree totype
= TREE_TYPE (TREE_TYPE (fn
));
2306 int i
, len
, viable
, flags
;
2307 tree parmlist
, parmnode
;
2309 struct rejection_reason
*reason
;
2311 for (parmlist
= totype
; TREE_CODE (parmlist
) != FUNCTION_TYPE
; )
2312 parmlist
= TREE_TYPE (parmlist
);
2313 parmlist
= TYPE_ARG_TYPES (parmlist
);
2315 len
= vec_safe_length (arglist
) + 1;
2316 convs
= alloc_conversions (len
);
2317 parmnode
= parmlist
;
2319 flags
= LOOKUP_IMPLICIT
;
2322 /* Don't bother looking up the same type twice. */
2323 if (*candidates
&& (*candidates
)->fn
== totype
)
2326 for (i
= 0; i
< len
; ++i
)
2328 tree arg
, argtype
, convert_type
= NULL_TREE
;
2334 arg
= (*arglist
)[i
- 1];
2335 argtype
= lvalue_type (arg
);
2339 t
= build_identity_conv (argtype
, NULL_TREE
);
2340 t
= build_conv (ck_user
, totype
, t
);
2341 /* Leave the 'cand' field null; we'll figure out the conversion in
2342 convert_like_real if this candidate is chosen. */
2343 convert_type
= totype
;
2345 else if (parmnode
== void_list_node
)
2349 t
= implicit_conversion (TREE_VALUE (parmnode
), argtype
, arg
,
2350 /*c_cast_p=*/false, flags
, complain
);
2351 convert_type
= TREE_VALUE (parmnode
);
2355 t
= build_identity_conv (argtype
, arg
);
2356 t
->ellipsis_p
= true;
2357 convert_type
= argtype
;
2367 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, arg
, convert_type
,
2368 EXPR_LOCATION (arg
));
2375 parmnode
= TREE_CHAIN (parmnode
);
2379 || ! sufficient_parms_p (parmnode
))
2381 int remaining
= remaining_arguments (parmnode
);
2383 reason
= arity_rejection (NULL_TREE
, i
+ remaining
, len
);
2386 return add_candidate (candidates
, totype
, obj
, arglist
, len
, convs
,
2387 access_path
, conversion_path
, viable
, reason
, flags
);
2391 build_builtin_candidate (struct z_candidate
**candidates
, tree fnname
,
2392 tree type1
, tree type2
, tree
*args
, tree
*argtypes
,
2393 int flags
, tsubst_flags_t complain
)
2400 struct rejection_reason
*reason
= NULL
;
2405 num_convs
= args
[2] ? 3 : (args
[1] ? 2 : 1);
2406 convs
= alloc_conversions (num_convs
);
2408 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2409 conversion ops are allowed. We handle that here by just checking for
2410 boolean_type_node because other operators don't ask for it. COND_EXPR
2411 also does contextual conversion to bool for the first operand, but we
2412 handle that in build_conditional_expr, and type1 here is operand 2. */
2413 if (type1
!= boolean_type_node
)
2414 flags
|= LOOKUP_ONLYCONVERTING
;
2416 for (i
= 0; i
< 2; ++i
)
2421 t
= implicit_conversion (types
[i
], argtypes
[i
], args
[i
],
2422 /*c_cast_p=*/false, flags
, complain
);
2426 /* We need something for printing the candidate. */
2427 t
= build_identity_conv (types
[i
], NULL_TREE
);
2428 reason
= arg_conversion_rejection (NULL_TREE
, i
, argtypes
[i
],
2429 types
[i
], EXPR_LOCATION (args
[i
]));
2434 reason
= bad_arg_conversion_rejection (NULL_TREE
, i
, args
[i
],
2436 EXPR_LOCATION (args
[i
]));
2441 /* For COND_EXPR we rearranged the arguments; undo that now. */
2444 convs
[2] = convs
[1];
2445 convs
[1] = convs
[0];
2446 t
= implicit_conversion (boolean_type_node
, argtypes
[2], args
[2],
2447 /*c_cast_p=*/false, flags
,
2454 reason
= arg_conversion_rejection (NULL_TREE
, 0, argtypes
[2],
2456 EXPR_LOCATION (args
[2]));
2460 add_candidate (candidates
, fnname
, /*first_arg=*/NULL_TREE
, /*args=*/NULL
,
2462 /*access_path=*/NULL_TREE
,
2463 /*conversion_path=*/NULL_TREE
,
2464 viable
, reason
, flags
);
2468 is_complete (tree t
)
2470 return COMPLETE_TYPE_P (complete_type (t
));
2473 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2476 promoted_arithmetic_type_p (tree type
)
2480 In this section, the term promoted integral type is used to refer
2481 to those integral types which are preserved by integral promotion
2482 (including e.g. int and long but excluding e.g. char).
2483 Similarly, the term promoted arithmetic type refers to promoted
2484 integral types plus floating types. */
2485 return ((CP_INTEGRAL_TYPE_P (type
)
2486 && same_type_p (type_promotes_to (type
), type
))
2487 || TREE_CODE (type
) == REAL_TYPE
);
2490 /* Create any builtin operator overload candidates for the operator in
2491 question given the converted operand types TYPE1 and TYPE2. The other
2492 args are passed through from add_builtin_candidates to
2493 build_builtin_candidate.
2495 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2496 If CODE is requires candidates operands of the same type of the kind
2497 of which TYPE1 and TYPE2 are, we add both candidates
2498 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2501 add_builtin_candidate (struct z_candidate
**candidates
, enum tree_code code
,
2502 enum tree_code code2
, tree fnname
, tree type1
,
2503 tree type2
, tree
*args
, tree
*argtypes
, int flags
,
2504 tsubst_flags_t complain
)
2508 case POSTINCREMENT_EXPR
:
2509 case POSTDECREMENT_EXPR
:
2510 args
[1] = integer_zero_node
;
2511 type2
= integer_type_node
;
2520 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2521 and VQ is either volatile or empty, there exist candidate operator
2522 functions of the form
2523 VQ T& operator++(VQ T&);
2524 T operator++(VQ T&, int);
2525 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2526 type other than bool, and VQ is either volatile or empty, there exist
2527 candidate operator functions of the form
2528 VQ T& operator--(VQ T&);
2529 T operator--(VQ T&, int);
2530 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2531 complete object type, and VQ is either volatile or empty, there exist
2532 candidate operator functions of the form
2533 T*VQ& operator++(T*VQ&);
2534 T*VQ& operator--(T*VQ&);
2535 T* operator++(T*VQ&, int);
2536 T* operator--(T*VQ&, int); */
2538 case POSTDECREMENT_EXPR
:
2539 case PREDECREMENT_EXPR
:
2540 if (TREE_CODE (type1
) == BOOLEAN_TYPE
)
2543 case POSTINCREMENT_EXPR
:
2544 case PREINCREMENT_EXPR
:
2545 if (ARITHMETIC_TYPE_P (type1
) || TYPE_PTROB_P (type1
))
2547 type1
= build_reference_type (type1
);
2552 /* 7 For every cv-qualified or cv-unqualified object type T, there
2553 exist candidate operator functions of the form
2557 8 For every function type T, there exist candidate operator functions of
2559 T& operator*(T*); */
2562 if (TYPE_PTR_P (type1
)
2563 && (TYPE_PTROB_P (type1
)
2564 || TREE_CODE (TREE_TYPE (type1
)) == FUNCTION_TYPE
))
2568 /* 9 For every type T, there exist candidate operator functions of the form
2571 10For every promoted arithmetic type T, there exist candidate operator
2572 functions of the form
2576 case UNARY_PLUS_EXPR
: /* unary + */
2577 if (TYPE_PTR_P (type1
))
2581 if (ARITHMETIC_TYPE_P (type1
))
2585 /* 11For every promoted integral type T, there exist candidate operator
2586 functions of the form
2590 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
))
2594 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2595 is the same type as C2 or is a derived class of C2, T is a complete
2596 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2597 there exist candidate operator functions of the form
2598 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2599 where CV12 is the union of CV1 and CV2. */
2602 if (TYPE_PTR_P (type1
) && TYPE_PTRMEM_P (type2
))
2604 tree c1
= TREE_TYPE (type1
);
2605 tree c2
= TYPE_PTRMEM_CLASS_TYPE (type2
);
2607 if (MAYBE_CLASS_TYPE_P (c1
) && DERIVED_FROM_P (c2
, c1
)
2608 && (TYPE_PTRMEMFUNC_P (type2
)
2609 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2
))))
2614 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2615 didate operator functions of the form
2620 bool operator<(L, R);
2621 bool operator>(L, R);
2622 bool operator<=(L, R);
2623 bool operator>=(L, R);
2624 bool operator==(L, R);
2625 bool operator!=(L, R);
2626 where LR is the result of the usual arithmetic conversions between
2629 14For every pair of types T and I, where T is a cv-qualified or cv-
2630 unqualified complete object type and I is a promoted integral type,
2631 there exist candidate operator functions of the form
2632 T* operator+(T*, I);
2633 T& operator[](T*, I);
2634 T* operator-(T*, I);
2635 T* operator+(I, T*);
2636 T& operator[](I, T*);
2638 15For every T, where T is a pointer to complete object type, there exist
2639 candidate operator functions of the form112)
2640 ptrdiff_t operator-(T, T);
2642 16For every pointer or enumeration type T, there exist candidate operator
2643 functions of the form
2644 bool operator<(T, T);
2645 bool operator>(T, T);
2646 bool operator<=(T, T);
2647 bool operator>=(T, T);
2648 bool operator==(T, T);
2649 bool operator!=(T, T);
2651 17For every pointer to member type T, there exist candidate operator
2652 functions of the form
2653 bool operator==(T, T);
2654 bool operator!=(T, T); */
2657 if (TYPE_PTROB_P (type1
) && TYPE_PTROB_P (type2
))
2659 if (TYPE_PTROB_P (type1
)
2660 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2662 type2
= ptrdiff_type_node
;
2667 case TRUNC_DIV_EXPR
:
2668 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2674 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2675 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
)))
2677 if (TYPE_PTRMEM_P (type1
) && null_ptr_cst_p (args
[1]))
2682 if (TYPE_PTRMEM_P (type2
) && null_ptr_cst_p (args
[0]))
2694 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2696 if (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2698 if (TREE_CODE (type1
) == ENUMERAL_TYPE
2699 && TREE_CODE (type2
) == ENUMERAL_TYPE
)
2701 if (TYPE_PTR_P (type1
)
2702 && null_ptr_cst_p (args
[1]))
2707 if (null_ptr_cst_p (args
[0])
2708 && TYPE_PTR_P (type2
))
2716 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2720 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && TYPE_PTROB_P (type2
))
2722 type1
= ptrdiff_type_node
;
2725 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2727 type2
= ptrdiff_type_node
;
2732 /* 18For every pair of promoted integral types L and R, there exist candi-
2733 date operator functions of the form
2740 where LR is the result of the usual arithmetic conversions between
2743 case TRUNC_MOD_EXPR
:
2749 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2753 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2754 type, VQ is either volatile or empty, and R is a promoted arithmetic
2755 type, there exist candidate operator functions of the form
2756 VQ L& operator=(VQ L&, R);
2757 VQ L& operator*=(VQ L&, R);
2758 VQ L& operator/=(VQ L&, R);
2759 VQ L& operator+=(VQ L&, R);
2760 VQ L& operator-=(VQ L&, R);
2762 20For every pair T, VQ), where T is any type and VQ is either volatile
2763 or empty, there exist candidate operator functions of the form
2764 T*VQ& operator=(T*VQ&, T*);
2766 21For every pair T, VQ), where T is a pointer to member type and VQ is
2767 either volatile or empty, there exist candidate operator functions of
2769 VQ T& operator=(VQ T&, T);
2771 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2772 unqualified complete object type, VQ is either volatile or empty, and
2773 I is a promoted integral type, there exist candidate operator func-
2775 T*VQ& operator+=(T*VQ&, I);
2776 T*VQ& operator-=(T*VQ&, I);
2778 23For every triple L, VQ, R), where L is an integral or enumeration
2779 type, VQ is either volatile or empty, and R is a promoted integral
2780 type, there exist candidate operator functions of the form
2782 VQ L& operator%=(VQ L&, R);
2783 VQ L& operator<<=(VQ L&, R);
2784 VQ L& operator>>=(VQ L&, R);
2785 VQ L& operator&=(VQ L&, R);
2786 VQ L& operator^=(VQ L&, R);
2787 VQ L& operator|=(VQ L&, R); */
2794 if (TYPE_PTROB_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2796 type2
= ptrdiff_type_node
;
2801 case TRUNC_DIV_EXPR
:
2802 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2806 case TRUNC_MOD_EXPR
:
2812 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1
) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2
))
2817 if (ARITHMETIC_TYPE_P (type1
) && ARITHMETIC_TYPE_P (type2
))
2819 if ((TYPE_PTRMEMFUNC_P (type1
) && TYPE_PTRMEMFUNC_P (type2
))
2820 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2821 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2822 || ((TYPE_PTRMEMFUNC_P (type1
)
2823 || TYPE_PTR_P (type1
))
2824 && null_ptr_cst_p (args
[1])))
2834 type1
= build_reference_type (type1
);
2840 For every pair of promoted arithmetic types L and R, there
2841 exist candidate operator functions of the form
2843 LR operator?(bool, L, R);
2845 where LR is the result of the usual arithmetic conversions
2846 between types L and R.
2848 For every type T, where T is a pointer or pointer-to-member
2849 type, there exist candidate operator functions of the form T
2850 operator?(bool, T, T); */
2852 if (promoted_arithmetic_type_p (type1
)
2853 && promoted_arithmetic_type_p (type2
))
2857 /* Otherwise, the types should be pointers. */
2858 if (!TYPE_PTR_OR_PTRMEM_P (type1
) || !TYPE_PTR_OR_PTRMEM_P (type2
))
2861 /* We don't check that the two types are the same; the logic
2862 below will actually create two candidates; one in which both
2863 parameter types are TYPE1, and one in which both parameter
2869 if (ARITHMETIC_TYPE_P (type1
))
2877 /* Make sure we don't create builtin candidates with dependent types. */
2878 bool u1
= uses_template_parms (type1
);
2879 bool u2
= type2
? uses_template_parms (type2
) : false;
2882 /* Try to recover if one of the types is non-dependent. But if
2883 there's only one type, there's nothing we can do. */
2886 /* And we lose if both are dependent. */
2889 /* Or if they have different forms. */
2890 if (TREE_CODE (type1
) != TREE_CODE (type2
))
2899 /* If we're dealing with two pointer types or two enumeral types,
2900 we need candidates for both of them. */
2901 if (type2
&& !same_type_p (type1
, type2
)
2902 && TREE_CODE (type1
) == TREE_CODE (type2
)
2903 && (TYPE_REF_P (type1
)
2904 || (TYPE_PTR_P (type1
) && TYPE_PTR_P (type2
))
2905 || (TYPE_PTRDATAMEM_P (type1
) && TYPE_PTRDATAMEM_P (type2
))
2906 || TYPE_PTRMEMFUNC_P (type1
)
2907 || MAYBE_CLASS_TYPE_P (type1
)
2908 || TREE_CODE (type1
) == ENUMERAL_TYPE
))
2910 if (TYPE_PTR_OR_PTRMEM_P (type1
))
2912 tree cptype
= composite_pointer_type (type1
, type2
,
2917 if (cptype
!= error_mark_node
)
2919 build_builtin_candidate
2920 (candidates
, fnname
, cptype
, cptype
, args
, argtypes
,
2926 build_builtin_candidate
2927 (candidates
, fnname
, type1
, type1
, args
, argtypes
, flags
, complain
);
2928 build_builtin_candidate
2929 (candidates
, fnname
, type2
, type2
, args
, argtypes
, flags
, complain
);
2933 build_builtin_candidate
2934 (candidates
, fnname
, type1
, type2
, args
, argtypes
, flags
, complain
);
2938 type_decays_to (tree type
)
2940 if (TREE_CODE (type
) == ARRAY_TYPE
)
2941 return build_pointer_type (TREE_TYPE (type
));
2942 if (TREE_CODE (type
) == FUNCTION_TYPE
)
2943 return build_pointer_type (type
);
2947 /* There are three conditions of builtin candidates:
2949 1) bool-taking candidates. These are the same regardless of the input.
2950 2) pointer-pair taking candidates. These are generated for each type
2951 one of the input types converts to.
2952 3) arithmetic candidates. According to the standard, we should generate
2953 all of these, but I'm trying not to...
2955 Here we generate a superset of the possible candidates for this particular
2956 case. That is a subset of the full set the standard defines, plus some
2957 other cases which the standard disallows. add_builtin_candidate will
2958 filter out the invalid set. */
2961 add_builtin_candidates (struct z_candidate
**candidates
, enum tree_code code
,
2962 enum tree_code code2
, tree fnname
, tree
*args
,
2963 int flags
, tsubst_flags_t complain
)
2967 tree type
, argtypes
[3], t
;
2968 /* TYPES[i] is the set of possible builtin-operator parameter types
2969 we will consider for the Ith argument. */
2970 vec
<tree
, va_gc
> *types
[2];
2973 for (i
= 0; i
< 3; ++i
)
2976 argtypes
[i
] = unlowered_expr_type (args
[i
]);
2978 argtypes
[i
] = NULL_TREE
;
2983 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2984 and VQ is either volatile or empty, there exist candidate operator
2985 functions of the form
2986 VQ T& operator++(VQ T&); */
2988 case POSTINCREMENT_EXPR
:
2989 case PREINCREMENT_EXPR
:
2990 case POSTDECREMENT_EXPR
:
2991 case PREDECREMENT_EXPR
:
2996 /* 24There also exist candidate operator functions of the form
2997 bool operator!(bool);
2998 bool operator&&(bool, bool);
2999 bool operator||(bool, bool); */
3001 case TRUTH_NOT_EXPR
:
3002 build_builtin_candidate
3003 (candidates
, fnname
, boolean_type_node
,
3004 NULL_TREE
, args
, argtypes
, flags
, complain
);
3007 case TRUTH_ORIF_EXPR
:
3008 case TRUTH_ANDIF_EXPR
:
3009 build_builtin_candidate
3010 (candidates
, fnname
, boolean_type_node
,
3011 boolean_type_node
, args
, argtypes
, flags
, complain
);
3033 types
[0] = make_tree_vector ();
3034 types
[1] = make_tree_vector ();
3036 for (i
= 0; i
< 2; ++i
)
3040 else if (MAYBE_CLASS_TYPE_P (argtypes
[i
]))
3044 if (i
== 0 && code
== MODIFY_EXPR
&& code2
== NOP_EXPR
)
3047 convs
= lookup_conversions (argtypes
[i
]);
3049 if (code
== COND_EXPR
)
3051 if (lvalue_p (args
[i
]))
3052 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3054 vec_safe_push (types
[i
], TYPE_MAIN_VARIANT (argtypes
[i
]));
3060 for (; convs
; convs
= TREE_CHAIN (convs
))
3062 type
= TREE_TYPE (convs
);
3065 && (!TYPE_REF_P (type
)
3066 || CP_TYPE_CONST_P (TREE_TYPE (type
))))
3069 if (code
== COND_EXPR
&& TYPE_REF_P (type
))
3070 vec_safe_push (types
[i
], type
);
3072 type
= non_reference (type
);
3073 if (i
!= 0 || ! ref1
)
3075 type
= cv_unqualified (type_decays_to (type
));
3076 if (enum_p
&& TREE_CODE (type
) == ENUMERAL_TYPE
)
3077 vec_safe_push (types
[i
], type
);
3078 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3079 type
= type_promotes_to (type
);
3082 if (! vec_member (type
, types
[i
]))
3083 vec_safe_push (types
[i
], type
);
3088 if (code
== COND_EXPR
&& lvalue_p (args
[i
]))
3089 vec_safe_push (types
[i
], build_reference_type (argtypes
[i
]));
3090 type
= non_reference (argtypes
[i
]);
3091 if (i
!= 0 || ! ref1
)
3093 type
= cv_unqualified (type_decays_to (type
));
3094 if (enum_p
&& UNSCOPED_ENUM_P (type
))
3095 vec_safe_push (types
[i
], type
);
3096 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type
))
3097 type
= type_promotes_to (type
);
3099 vec_safe_push (types
[i
], type
);
3103 /* Run through the possible parameter types of both arguments,
3104 creating candidates with those parameter types. */
3105 FOR_EACH_VEC_ELT_REVERSE (*(types
[0]), ix
, t
)
3110 if (!types
[1]->is_empty ())
3111 FOR_EACH_VEC_ELT_REVERSE (*(types
[1]), jx
, u
)
3112 add_builtin_candidate
3113 (candidates
, code
, code2
, fnname
, t
,
3114 u
, args
, argtypes
, flags
, complain
);
3116 add_builtin_candidate
3117 (candidates
, code
, code2
, fnname
, t
,
3118 NULL_TREE
, args
, argtypes
, flags
, complain
);
3121 release_tree_vector (types
[0]);
3122 release_tree_vector (types
[1]);
3126 /* If TMPL can be successfully instantiated as indicated by
3127 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
3129 TMPL is the template. EXPLICIT_TARGS are any explicit template
3130 arguments. ARGLIST is the arguments provided at the call-site.
3131 This does not change ARGLIST. The RETURN_TYPE is the desired type
3132 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
3133 as for add_function_candidate. If an OBJ is supplied, FLAGS and
3134 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
3136 static struct z_candidate
*
3137 add_template_candidate_real (struct z_candidate
**candidates
, tree tmpl
,
3138 tree ctype
, tree explicit_targs
, tree first_arg
,
3139 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3140 tree access_path
, tree conversion_path
,
3141 int flags
, tree obj
, unification_kind_t strict
,
3142 tsubst_flags_t complain
)
3144 int ntparms
= DECL_NTPARMS (tmpl
);
3145 tree targs
= make_tree_vec (ntparms
);
3146 unsigned int len
= vec_safe_length (arglist
);
3147 unsigned int nargs
= (first_arg
== NULL_TREE
? 0 : 1) + len
;
3148 unsigned int skip_without_in_chrg
= 0;
3149 tree first_arg_without_in_chrg
= first_arg
;
3150 tree
*args_without_in_chrg
;
3151 unsigned int nargs_without_in_chrg
;
3152 unsigned int ia
, ix
;
3154 struct z_candidate
*cand
;
3156 struct rejection_reason
*reason
= NULL
;
3158 conversion
**convs
= NULL
;
3160 /* We don't do deduction on the in-charge parameter, the VTT
3161 parameter or 'this'. */
3162 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl
))
3164 if (first_arg_without_in_chrg
!= NULL_TREE
)
3165 first_arg_without_in_chrg
= NULL_TREE
;
3166 else if (return_type
&& strict
== DEDUCE_CALL
)
3167 /* We're deducing for a call to the result of a template conversion
3168 function, so the args don't contain 'this'; leave them alone. */;
3170 ++skip_without_in_chrg
;
3173 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl
)
3174 || DECL_BASE_CONSTRUCTOR_P (tmpl
))
3175 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl
)))
3177 if (first_arg_without_in_chrg
!= NULL_TREE
)
3178 first_arg_without_in_chrg
= NULL_TREE
;
3180 ++skip_without_in_chrg
;
3183 if (len
< skip_without_in_chrg
)
3186 if (DECL_CONSTRUCTOR_P (tmpl
) && nargs
== 2
3187 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (first_arg
),
3188 TREE_TYPE ((*arglist
)[0])))
3190 /* 12.8/6 says, "A declaration of a constructor for a class X is
3191 ill-formed if its first parameter is of type (optionally cv-qualified)
3192 X and either there are no other parameters or else all other
3193 parameters have default arguments. A member function template is never
3194 instantiated to produce such a constructor signature."
3196 So if we're trying to copy an object of the containing class, don't
3197 consider a template constructor that has a first parameter type that
3198 is just a template parameter, as we would deduce a signature that we
3199 would then reject in the code below. */
3200 if (tree firstparm
= FUNCTION_FIRST_USER_PARMTYPE (tmpl
))
3202 firstparm
= TREE_VALUE (firstparm
);
3203 if (PACK_EXPANSION_P (firstparm
))
3204 firstparm
= PACK_EXPANSION_PATTERN (firstparm
);
3205 if (TREE_CODE (firstparm
) == TEMPLATE_TYPE_PARM
)
3207 gcc_assert (!explicit_targs
);
3208 reason
= invalid_copy_with_fn_template_rejection ();
3214 nargs_without_in_chrg
= ((first_arg_without_in_chrg
!= NULL_TREE
? 1 : 0)
3215 + (len
- skip_without_in_chrg
));
3216 args_without_in_chrg
= XALLOCAVEC (tree
, nargs_without_in_chrg
);
3218 if (first_arg_without_in_chrg
!= NULL_TREE
)
3220 args_without_in_chrg
[ia
] = first_arg_without_in_chrg
;
3223 for (ix
= skip_without_in_chrg
;
3224 vec_safe_iterate (arglist
, ix
, &arg
);
3227 args_without_in_chrg
[ia
] = arg
;
3230 gcc_assert (ia
== nargs_without_in_chrg
);
3232 errs
= errorcount
+sorrycount
;
3234 convs
= alloc_conversions (nargs
);
3235 fn
= fn_type_unification (tmpl
, explicit_targs
, targs
,
3236 args_without_in_chrg
,
3237 nargs_without_in_chrg
,
3238 return_type
, strict
, flags
, convs
,
3239 false, complain
& tf_decltype
);
3241 if (fn
== error_mark_node
)
3243 /* Don't repeat unification later if it already resulted in errors. */
3244 if (errorcount
+sorrycount
== errs
)
3245 reason
= template_unification_rejection (tmpl
, explicit_targs
,
3246 targs
, args_without_in_chrg
,
3247 nargs_without_in_chrg
,
3248 return_type
, strict
, flags
);
3250 reason
= template_unification_error_rejection ();
3254 /* Now the explicit specifier might have been deduced; check if this
3255 declaration is explicit. If it is and we're ignoring non-converting
3256 constructors, don't add this function to the set of candidates. */
3257 if ((flags
& LOOKUP_ONLYCONVERTING
) && DECL_NONCONVERTING_P (fn
))
3260 if (DECL_CONSTRUCTOR_P (fn
) && nargs
== 2)
3262 tree arg_types
= FUNCTION_FIRST_USER_PARMTYPE (fn
);
3263 if (arg_types
&& same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types
)),
3266 /* We're trying to produce a constructor with a prohibited signature,
3267 as discussed above; handle here any cases we didn't catch then,
3269 reason
= invalid_copy_with_fn_template_rejection ();
3274 if (obj
!= NULL_TREE
)
3275 /* Aha, this is a conversion function. */
3276 cand
= add_conv_candidate (candidates
, fn
, obj
, arglist
,
3277 access_path
, conversion_path
, complain
);
3279 cand
= add_function_candidate (candidates
, fn
, ctype
,
3280 first_arg
, arglist
, access_path
,
3281 conversion_path
, flags
, convs
, complain
);
3282 if (DECL_TI_TEMPLATE (fn
) != tmpl
)
3283 /* This situation can occur if a member template of a template
3284 class is specialized. Then, instantiate_template might return
3285 an instantiation of the specialization, in which case the
3286 DECL_TI_TEMPLATE field will point at the original
3287 specialization. For example:
3289 template <class T> struct S { template <class U> void f(U);
3290 template <> void f(int) {}; };
3294 Here, TMPL will be template <class U> S<double>::f(U).
3295 And, instantiate template will give us the specialization
3296 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3297 for this will point at template <class T> template <> S<T>::f(int),
3298 so that we can find the definition. For the purposes of
3299 overload resolution, however, we want the original TMPL. */
3300 cand
->template_decl
= build_template_info (tmpl
, targs
);
3302 cand
->template_decl
= DECL_TEMPLATE_INFO (fn
);
3303 cand
->explicit_targs
= explicit_targs
;
3307 return add_candidate (candidates
, tmpl
, first_arg
, arglist
, nargs
, NULL
,
3308 access_path
, conversion_path
, 0, reason
, flags
);
3312 static struct z_candidate
*
3313 add_template_candidate (struct z_candidate
**candidates
, tree tmpl
, tree ctype
,
3314 tree explicit_targs
, tree first_arg
,
3315 const vec
<tree
, va_gc
> *arglist
, tree return_type
,
3316 tree access_path
, tree conversion_path
, int flags
,
3317 unification_kind_t strict
, tsubst_flags_t complain
)
3320 add_template_candidate_real (candidates
, tmpl
, ctype
,
3321 explicit_targs
, first_arg
, arglist
,
3322 return_type
, access_path
, conversion_path
,
3323 flags
, NULL_TREE
, strict
, complain
);
3326 /* Create an overload candidate for the conversion function template TMPL,
3327 returning RETURN_TYPE, which will be invoked for expression OBJ to produce a
3328 pointer-to-function which will in turn be called with the argument list
3329 ARGLIST, and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
3330 passed on to implicit_conversion. */
3332 static struct z_candidate
*
3333 add_template_conv_candidate (struct z_candidate
**candidates
, tree tmpl
,
3335 const vec
<tree
, va_gc
> *arglist
,
3336 tree return_type
, tree access_path
,
3337 tree conversion_path
, tsubst_flags_t complain
)
3339 /* Making this work broke PR 71117 and 85118, so until the committee resolves
3340 core issue 2189, let's disable this candidate if there are any call
3346 add_template_candidate_real (candidates
, tmpl
, NULL_TREE
, NULL_TREE
,
3347 NULL_TREE
, arglist
, return_type
, access_path
,
3348 conversion_path
, 0, obj
, DEDUCE_CALL
,
3352 /* The CANDS are the set of candidates that were considered for
3353 overload resolution. Return the set of viable candidates, or CANDS
3354 if none are viable. If any of the candidates were viable, set
3355 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3356 considered viable only if it is strictly viable. */
3358 static struct z_candidate
*
3359 splice_viable (struct z_candidate
*cands
,
3363 struct z_candidate
*viable
;
3364 struct z_candidate
**last_viable
;
3365 struct z_candidate
**cand
;
3366 bool found_strictly_viable
= false;
3368 /* Be strict inside templates, since build_over_call won't actually
3369 do the conversions to get pedwarns. */
3370 if (processing_template_decl
)
3374 last_viable
= &viable
;
3375 *any_viable_p
= false;
3380 struct z_candidate
*c
= *cand
;
3382 && (c
->viable
== 1 || TREE_CODE (c
->fn
) == TEMPLATE_DECL
))
3384 /* Be strict in the presence of a viable candidate. Also if
3385 there are template candidates, so that we get deduction errors
3386 for them instead of silently preferring a bad conversion. */
3388 if (viable
&& !found_strictly_viable
)
3390 /* Put any spliced near matches back onto the main list so
3391 that we see them if there is no strict match. */
3392 *any_viable_p
= false;
3393 *last_viable
= cands
;
3396 last_viable
= &viable
;
3400 if (strict_p
? c
->viable
== 1 : c
->viable
)
3405 last_viable
= &c
->next
;
3406 *any_viable_p
= true;
3408 found_strictly_viable
= true;
3414 return viable
? viable
: cands
;
3418 any_strictly_viable (struct z_candidate
*cands
)
3420 for (; cands
; cands
= cands
->next
)
3421 if (cands
->viable
== 1)
3426 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3427 words, it is about to become the "this" pointer for a member
3428 function call. Take the address of the object. */
3431 build_this (tree obj
)
3433 /* In a template, we are only concerned about the type of the
3434 expression, so we can take a shortcut. */
3435 if (processing_template_decl
)
3436 return build_address (obj
);
3438 return cp_build_addr_expr (obj
, tf_warning_or_error
);
3441 /* Returns true iff functions are equivalent. Equivalent functions are
3442 not '==' only if one is a function-local extern function or if
3443 both are extern "C". */
3446 equal_functions (tree fn1
, tree fn2
)
3448 if (TREE_CODE (fn1
) != TREE_CODE (fn2
))
3450 if (TREE_CODE (fn1
) == TEMPLATE_DECL
)
3452 if (DECL_LOCAL_FUNCTION_P (fn1
) || DECL_LOCAL_FUNCTION_P (fn2
)
3453 || DECL_EXTERN_C_FUNCTION_P (fn1
))
3454 return decls_match (fn1
, fn2
);
3458 /* Print information about a candidate FN being rejected due to INFO. */
3461 print_conversion_rejection (location_t loc
, struct conversion_info
*info
,
3464 tree from
= info
->from
;
3466 from
= lvalue_type (from
);
3467 if (info
->n_arg
== -1)
3469 /* Conversion of implicit `this' argument failed. */
3470 if (!TYPE_P (info
->from
))
3471 /* A bad conversion for 'this' must be discarding cv-quals. */
3472 inform (loc
, " passing %qT as %<this%> "
3473 "argument discards qualifiers",
3476 inform (loc
, " no known conversion for implicit "
3477 "%<this%> parameter from %qH to %qI",
3478 from
, info
->to_type
);
3480 else if (!TYPE_P (info
->from
))
3482 if (info
->n_arg
>= 0)
3483 inform (loc
, " conversion of argument %d would be ill-formed:",
3485 perform_implicit_conversion (info
->to_type
, info
->from
,
3486 tf_warning_or_error
);
3488 else if (info
->n_arg
== -2)
3489 /* Conversion of conversion function return value failed. */
3490 inform (loc
, " no known conversion from %qH to %qI",
3491 from
, info
->to_type
);
3494 if (TREE_CODE (fn
) == FUNCTION_DECL
)
3495 loc
= get_fndecl_argument_location (fn
, info
->n_arg
);
3496 inform (loc
, " no known conversion for argument %d from %qH to %qI",
3497 info
->n_arg
+ 1, from
, info
->to_type
);
3501 /* Print information about a candidate with WANT parameters and we found
3505 print_arity_information (location_t loc
, unsigned int have
, unsigned int want
)
3507 inform_n (loc
, want
,
3508 " candidate expects %d argument, %d provided",
3509 " candidate expects %d arguments, %d provided",
3513 /* Print information about one overload candidate CANDIDATE. MSGSTR
3514 is the text to print before the candidate itself.
3516 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3517 to have been run through gettext by the caller. This wart makes
3518 life simpler in print_z_candidates and for the translators. */
3521 print_z_candidate (location_t loc
, const char *msgstr
,
3522 struct z_candidate
*candidate
)
3524 const char *msg
= (msgstr
== NULL
3526 : ACONCAT ((msgstr
, " ", NULL
)));
3527 tree fn
= candidate
->fn
;
3528 if (flag_new_inheriting_ctors
)
3529 fn
= strip_inheriting_ctors (fn
);
3530 location_t cloc
= location_of (fn
);
3532 if (identifier_p (fn
))
3535 if (candidate
->num_convs
== 3)
3536 inform (cloc
, "%s%<%D(%T, %T, %T)%> <built-in>", msg
, fn
,
3537 candidate
->convs
[0]->type
,
3538 candidate
->convs
[1]->type
,
3539 candidate
->convs
[2]->type
);
3540 else if (candidate
->num_convs
== 2)
3541 inform (cloc
, "%s%<%D(%T, %T)%> <built-in>", msg
, fn
,
3542 candidate
->convs
[0]->type
,
3543 candidate
->convs
[1]->type
);
3545 inform (cloc
, "%s%<%D(%T)%> <built-in>", msg
, fn
,
3546 candidate
->convs
[0]->type
);
3548 else if (TYPE_P (fn
))
3549 inform (cloc
, "%s%qT <conversion>", msg
, fn
);
3550 else if (candidate
->viable
== -1)
3551 inform (cloc
, "%s%#qD <near match>", msg
, fn
);
3552 else if (DECL_DELETED_FN (fn
))
3553 inform (cloc
, "%s%#qD <deleted>", msg
, fn
);
3555 inform (cloc
, "%s%#qD", msg
, fn
);
3556 if (fn
!= candidate
->fn
)
3558 cloc
= location_of (candidate
->fn
);
3559 inform (cloc
, " inherited here");
3561 /* Give the user some information about why this candidate failed. */
3562 if (candidate
->reason
!= NULL
)
3564 struct rejection_reason
*r
= candidate
->reason
;
3569 print_arity_information (cloc
, r
->u
.arity
.actual
,
3570 r
->u
.arity
.expected
);
3572 case rr_arg_conversion
:
3573 print_conversion_rejection (cloc
, &r
->u
.conversion
, fn
);
3575 case rr_bad_arg_conversion
:
3576 print_conversion_rejection (cloc
, &r
->u
.bad_conversion
, fn
);
3578 case rr_explicit_conversion
:
3579 inform (cloc
, " return type %qT of explicit conversion function "
3580 "cannot be converted to %qT with a qualification "
3581 "conversion", r
->u
.conversion
.from
,
3582 r
->u
.conversion
.to_type
);
3584 case rr_template_conversion
:
3585 inform (cloc
, " conversion from return type %qT of template "
3586 "conversion function specialization to %qT is not an "
3587 "exact match", r
->u
.conversion
.from
,
3588 r
->u
.conversion
.to_type
);
3590 case rr_template_unification
:
3591 /* We use template_unification_error_rejection if unification caused
3592 actual non-SFINAE errors, in which case we don't need to repeat
3594 if (r
->u
.template_unification
.tmpl
== NULL_TREE
)
3596 inform (cloc
, " substitution of deduced template arguments "
3597 "resulted in errors seen above");
3600 /* Re-run template unification with diagnostics. */
3601 inform (cloc
, " template argument deduction/substitution failed:");
3602 fn_type_unification (r
->u
.template_unification
.tmpl
,
3603 r
->u
.template_unification
.explicit_targs
,
3605 (r
->u
.template_unification
.num_targs
)),
3606 r
->u
.template_unification
.args
,
3607 r
->u
.template_unification
.nargs
,
3608 r
->u
.template_unification
.return_type
,
3609 r
->u
.template_unification
.strict
,
3610 r
->u
.template_unification
.flags
,
3613 case rr_invalid_copy
:
3615 " a constructor taking a single argument of its own "
3616 "class type is invalid");
3618 case rr_constraint_failure
:
3620 tree tmpl
= r
->u
.template_instantiation
.tmpl
;
3621 tree args
= r
->u
.template_instantiation
.targs
;
3622 diagnose_constraints (cloc
, tmpl
, args
);
3625 case rr_inherited_ctor
:
3626 inform (cloc
, " an inherited constructor is not a candidate for "
3627 "initialization from an expression of the same or derived "
3632 /* This candidate didn't have any issues or we failed to
3633 handle a particular code. Either way... */
3640 print_z_candidates (location_t loc
, struct z_candidate
*candidates
)
3642 struct z_candidate
*cand1
;
3643 struct z_candidate
**cand2
;
3648 /* Remove non-viable deleted candidates. */
3650 for (cand2
= &cand1
; *cand2
; )
3652 if (TREE_CODE ((*cand2
)->fn
) == FUNCTION_DECL
3653 && !(*cand2
)->viable
3654 && DECL_DELETED_FN ((*cand2
)->fn
))
3655 *cand2
= (*cand2
)->next
;
3657 cand2
= &(*cand2
)->next
;
3659 /* ...if there are any non-deleted ones. */
3663 /* There may be duplicates in the set of candidates. We put off
3664 checking this condition as long as possible, since we have no way
3665 to eliminate duplicates from a set of functions in less than n^2
3666 time. Now we are about to emit an error message, so it is more
3667 permissible to go slowly. */
3668 for (cand1
= candidates
; cand1
; cand1
= cand1
->next
)
3670 tree fn
= cand1
->fn
;
3671 /* Skip builtin candidates and conversion functions. */
3674 cand2
= &cand1
->next
;
3677 if (DECL_P ((*cand2
)->fn
)
3678 && equal_functions (fn
, (*cand2
)->fn
))
3679 *cand2
= (*cand2
)->next
;
3681 cand2
= &(*cand2
)->next
;
3685 for (; candidates
; candidates
= candidates
->next
)
3686 print_z_candidate (loc
, "candidate:", candidates
);
3689 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3690 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3691 the result of the conversion function to convert it to the final
3692 desired type. Merge the two sequences into a single sequence,
3693 and return the merged sequence. */
3696 merge_conversion_sequences (conversion
*user_seq
, conversion
*std_seq
)
3699 bool bad
= user_seq
->bad_p
;
3701 gcc_assert (user_seq
->kind
== ck_user
);
3703 /* Find the end of the second conversion sequence. */
3704 for (t
= &std_seq
; (*t
)->kind
!= ck_identity
; t
= &((*t
)->u
.next
))
3706 /* The entire sequence is a user-conversion sequence. */
3707 (*t
)->user_conv_p
= true;
3712 if ((*t
)->rvaluedness_matches_p
)
3713 /* We're binding a reference directly to the result of the conversion.
3714 build_user_type_conversion_1 stripped the REFERENCE_TYPE from the return
3715 type, but we want it back. */
3716 user_seq
->type
= TREE_TYPE (TREE_TYPE (user_seq
->cand
->fn
));
3718 /* Replace the identity conversion with the user conversion
3725 /* Handle overload resolution for initializing an object of class type from
3726 an initializer list. First we look for a suitable constructor that
3727 takes a std::initializer_list; if we don't find one, we then look for a
3728 non-list constructor.
3730 Parameters are as for add_candidates, except that the arguments are in
3731 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3732 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3735 add_list_candidates (tree fns
, tree first_arg
,
3736 const vec
<tree
, va_gc
> *args
, tree totype
,
3737 tree explicit_targs
, bool template_only
,
3738 tree conversion_path
, tree access_path
,
3740 struct z_candidate
**candidates
,
3741 tsubst_flags_t complain
)
3743 gcc_assert (*candidates
== NULL
);
3745 /* We're looking for a ctor for list-initialization. */
3746 flags
|= LOOKUP_LIST_INIT_CTOR
;
3747 /* And we don't allow narrowing conversions. We also use this flag to
3748 avoid the copy constructor call for copy-list-initialization. */
3749 flags
|= LOOKUP_NO_NARROWING
;
3751 unsigned nart
= num_artificial_parms_for (OVL_FIRST (fns
)) - 1;
3752 tree init_list
= (*args
)[nart
];
3754 /* Always use the default constructor if the list is empty (DR 990). */
3755 if (CONSTRUCTOR_NELTS (init_list
) == 0
3756 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
3758 /* If the class has a list ctor, try passing the list as a single
3759 argument first, but only consider list ctors. */
3760 else if (TYPE_HAS_LIST_CTOR (totype
))
3762 flags
|= LOOKUP_LIST_ONLY
;
3763 add_candidates (fns
, first_arg
, args
, NULL_TREE
,
3764 explicit_targs
, template_only
, conversion_path
,
3765 access_path
, flags
, candidates
, complain
);
3766 if (any_strictly_viable (*candidates
))
3770 /* Expand the CONSTRUCTOR into a new argument vec. */
3771 vec
<tree
, va_gc
> *new_args
;
3772 vec_alloc (new_args
, nart
+ CONSTRUCTOR_NELTS (init_list
));
3773 for (unsigned i
= 0; i
< nart
; ++i
)
3774 new_args
->quick_push ((*args
)[i
]);
3775 for (unsigned i
= 0; i
< CONSTRUCTOR_NELTS (init_list
); ++i
)
3776 new_args
->quick_push (CONSTRUCTOR_ELT (init_list
, i
)->value
);
3778 /* We aren't looking for list-ctors anymore. */
3779 flags
&= ~LOOKUP_LIST_ONLY
;
3780 /* We allow more user-defined conversions within an init-list. */
3781 flags
&= ~LOOKUP_NO_CONVERSION
;
3783 add_candidates (fns
, first_arg
, new_args
, NULL_TREE
,
3784 explicit_targs
, template_only
, conversion_path
,
3785 access_path
, flags
, candidates
, complain
);
3788 /* Returns the best overload candidate to perform the requested
3789 conversion. This function is used for three the overloading situations
3790 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3791 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3792 per [dcl.init.ref], so we ignore temporary bindings. */
3794 static struct z_candidate
*
3795 build_user_type_conversion_1 (tree totype
, tree expr
, int flags
,
3796 tsubst_flags_t complain
)
3798 struct z_candidate
*candidates
, *cand
;
3800 tree ctors
= NULL_TREE
;
3801 tree conv_fns
= NULL_TREE
;
3802 conversion
*conv
= NULL
;
3803 tree first_arg
= NULL_TREE
;
3804 vec
<tree
, va_gc
> *args
= NULL
;
3811 fromtype
= TREE_TYPE (expr
);
3813 /* We represent conversion within a hierarchy using RVALUE_CONV and
3814 BASE_CONV, as specified by [over.best.ics]; these become plain
3815 constructor calls, as specified in [dcl.init]. */
3816 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype
) || !MAYBE_CLASS_TYPE_P (totype
)
3817 || !DERIVED_FROM_P (totype
, fromtype
));
3819 if (CLASS_TYPE_P (totype
))
3820 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3821 creating a garbage BASELINK; constructors can't be inherited. */
3822 ctors
= get_class_binding (totype
, complete_ctor_identifier
);
3824 if (MAYBE_CLASS_TYPE_P (fromtype
))
3826 tree to_nonref
= non_reference (totype
);
3827 if (same_type_ignoring_top_level_qualifiers_p (to_nonref
, fromtype
) ||
3828 (CLASS_TYPE_P (to_nonref
) && CLASS_TYPE_P (fromtype
)
3829 && DERIVED_FROM_P (to_nonref
, fromtype
)))
3831 /* [class.conv.fct] A conversion function is never used to
3832 convert a (possibly cv-qualified) object to the (possibly
3833 cv-qualified) same object type (or a reference to it), to a
3834 (possibly cv-qualified) base class of that type (or a
3835 reference to it)... */
3838 conv_fns
= lookup_conversions (fromtype
);
3842 flags
|= LOOKUP_NO_CONVERSION
;
3843 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3844 flags
|= LOOKUP_NO_NARROWING
;
3846 /* It's OK to bind a temporary for converting constructor arguments, but
3847 not in converting the return value of a conversion operator. */
3848 convflags
= ((flags
& LOOKUP_NO_TEMP_BIND
) | LOOKUP_NO_CONVERSION
3849 | (flags
& LOOKUP_NO_NARROWING
));
3850 flags
&= ~LOOKUP_NO_TEMP_BIND
;
3854 int ctorflags
= flags
;
3856 first_arg
= build_dummy_object (totype
);
3858 /* We should never try to call the abstract or base constructor
3860 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_FIRST (ctors
))
3861 && !DECL_HAS_VTT_PARM_P (OVL_FIRST (ctors
)));
3863 args
= make_tree_vector_single (expr
);
3864 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3866 /* List-initialization. */
3867 add_list_candidates (ctors
, first_arg
, args
, totype
, NULL_TREE
,
3868 false, TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3869 ctorflags
, &candidates
, complain
);
3873 add_candidates (ctors
, first_arg
, args
, NULL_TREE
, NULL_TREE
, false,
3874 TYPE_BINFO (totype
), TYPE_BINFO (totype
),
3875 ctorflags
, &candidates
, complain
);
3878 for (cand
= candidates
; cand
; cand
= cand
->next
)
3880 cand
->second_conv
= build_identity_conv (totype
, NULL_TREE
);
3882 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3883 set, then this is copy-initialization. In that case, "The
3884 result of the call is then used to direct-initialize the
3885 object that is the destination of the copy-initialization."
3888 We represent this in the conversion sequence with an
3889 rvalue conversion, which means a constructor call. */
3890 if (!TYPE_REF_P (totype
)
3891 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3893 = build_conv (ck_rvalue
, totype
, cand
->second_conv
);
3899 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
3900 first_arg
= CONSTRUCTOR_ELT (expr
, 0)->value
;
3905 for (; conv_fns
; conv_fns
= TREE_CHAIN (conv_fns
))
3907 tree conversion_path
= TREE_PURPOSE (conv_fns
);
3908 struct z_candidate
*old_candidates
;
3910 /* If we are called to convert to a reference type, we are trying to
3911 find a direct binding, so don't even consider temporaries. If
3912 we don't find a direct binding, the caller will try again to
3913 look for a temporary binding. */
3914 if (TYPE_REF_P (totype
))
3915 convflags
|= LOOKUP_NO_TEMP_BIND
;
3917 old_candidates
= candidates
;
3918 add_candidates (TREE_VALUE (conv_fns
), first_arg
, NULL
, totype
,
3920 conversion_path
, TYPE_BINFO (fromtype
),
3921 flags
, &candidates
, complain
);
3923 for (cand
= candidates
; cand
!= old_candidates
; cand
= cand
->next
)
3925 tree rettype
= TREE_TYPE (TREE_TYPE (cand
->fn
));
3927 = implicit_conversion (totype
,
3930 /*c_cast_p=*/false, convflags
,
3933 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3934 copy-initialization. In that case, "The result of the
3935 call is then used to direct-initialize the object that is
3936 the destination of the copy-initialization." [dcl.init]
3938 We represent this in the conversion sequence with an
3939 rvalue conversion, which means a constructor call. But
3940 don't add a second rvalue conversion if there's already
3941 one there. Which there really shouldn't be, but it's
3942 harmless since we'd add it here anyway. */
3943 if (ics
&& MAYBE_CLASS_TYPE_P (totype
) && ics
->kind
!= ck_rvalue
3944 && !(convflags
& LOOKUP_NO_TEMP_BIND
))
3945 ics
= build_conv (ck_rvalue
, totype
, ics
);
3947 cand
->second_conv
= ics
;
3952 cand
->reason
= arg_conversion_rejection (NULL_TREE
, -2,
3954 EXPR_LOCATION (expr
));
3956 else if (DECL_NONCONVERTING_P (cand
->fn
)
3957 && ics
->rank
> cr_exact
)
3959 /* 13.3.1.5: For direct-initialization, those explicit
3960 conversion functions that are not hidden within S and
3961 yield type T or a type that can be converted to type T
3962 with a qualification conversion (4.4) are also candidate
3964 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3965 I've raised this issue with the committee. --jason 9/2011 */
3967 cand
->reason
= explicit_conversion_rejection (rettype
, totype
);
3969 else if (cand
->viable
== 1 && ics
->bad_p
)
3973 = bad_arg_conversion_rejection (NULL_TREE
, -2,
3975 EXPR_LOCATION (expr
));
3977 else if (primary_template_specialization_p (cand
->fn
)
3978 && ics
->rank
> cr_exact
)
3980 /* 13.3.3.1.2: If the user-defined conversion is specified by
3981 a specialization of a conversion function template, the
3982 second standard conversion sequence shall have exact match
3985 cand
->reason
= template_conversion_rejection (rettype
, totype
);
3990 candidates
= splice_viable (candidates
, false, &any_viable_p
);
3994 release_tree_vector (args
);
3998 cand
= tourney (candidates
, complain
);
4001 if (complain
& tf_error
)
4003 auto_diagnostic_group d
;
4004 error ("conversion from %qH to %qI is ambiguous",
4006 print_z_candidates (location_of (expr
), candidates
);
4009 cand
= candidates
; /* any one will do */
4010 cand
->second_conv
= build_ambiguous_conv (totype
, expr
);
4011 cand
->second_conv
->user_conv_p
= true;
4012 if (!any_strictly_viable (candidates
))
4013 cand
->second_conv
->bad_p
= true;
4014 if (flags
& LOOKUP_ONLYCONVERTING
)
4015 cand
->second_conv
->need_temporary_p
= true;
4016 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
4017 ambiguous conversion is no worse than another user-defined
4024 if (!DECL_CONSTRUCTOR_P (cand
->fn
))
4025 convtype
= non_reference (TREE_TYPE (TREE_TYPE (cand
->fn
)));
4026 else if (cand
->second_conv
->kind
== ck_rvalue
)
4027 /* DR 5: [in the first step of copy-initialization]...if the function
4028 is a constructor, the call initializes a temporary of the
4029 cv-unqualified version of the destination type. */
4030 convtype
= cv_unqualified (totype
);
4033 /* Build the user conversion sequence. */
4037 build_identity_conv (TREE_TYPE (expr
), expr
));
4039 if (cand
->viable
== -1)
4042 /* We're performing the maybe-rvalue overload resolution and
4043 a conversion function is in play. Reject converting the return
4044 value of the conversion function to a base class. */
4045 if ((flags
& LOOKUP_PREFER_RVALUE
) && !DECL_CONSTRUCTOR_P (cand
->fn
))
4046 for (conversion
*t
= cand
->second_conv
; t
; t
= next_conversion (t
))
4047 if (t
->kind
== ck_base
)
4050 /* Remember that this was a list-initialization. */
4051 if (flags
& LOOKUP_NO_NARROWING
)
4052 conv
->check_narrowing
= true;
4054 /* Combine it with the second conversion sequence. */
4055 cand
->second_conv
= merge_conversion_sequences (conv
,
4061 /* Wrapper for above. */
4064 build_user_type_conversion (tree totype
, tree expr
, int flags
,
4065 tsubst_flags_t complain
)
4067 struct z_candidate
*cand
;
4070 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4071 cand
= build_user_type_conversion_1 (totype
, expr
, flags
, complain
);
4075 if (cand
->second_conv
->kind
== ck_ambig
)
4076 ret
= error_mark_node
;
4079 expr
= convert_like (cand
->second_conv
, expr
, complain
);
4080 ret
= convert_from_reference (expr
);
4086 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4090 /* Subroutine of convert_nontype_argument.
4092 EXPR is an expression used in a context that requires a converted
4093 constant-expression, such as a template non-type parameter. Do any
4094 necessary conversions (that are permitted for converted
4095 constant-expressions) to convert it to the desired type.
4097 If conversion is successful, returns the converted expression;
4098 otherwise, returns error_mark_node. */
4101 build_converted_constant_expr (tree type
, tree expr
, tsubst_flags_t complain
)
4106 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
4108 if (error_operand_p (expr
))
4109 return error_mark_node
;
4111 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4112 p
= conversion_obstack_alloc (0);
4114 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
4116 LOOKUP_IMPLICIT
, complain
);
4118 /* A converted constant expression of type T is an expression, implicitly
4119 converted to type T, where the converted expression is a constant
4120 expression and the implicit conversion sequence contains only
4122 * user-defined conversions,
4123 * lvalue-to-rvalue conversions (7.1),
4124 * array-to-pointer conversions (7.2),
4125 * function-to-pointer conversions (7.3),
4126 * qualification conversions (7.5),
4127 * integral promotions (7.6),
4128 * integral conversions (7.8) other than narrowing conversions (11.6.4),
4129 * null pointer conversions (7.11) from std::nullptr_t,
4130 * null member pointer conversions (7.12) from std::nullptr_t, and
4131 * function pointer conversions (7.13),
4133 and where the reference binding (if any) binds directly. */
4135 for (conversion
*c
= conv
;
4136 conv
&& c
->kind
!= ck_identity
;
4137 c
= next_conversion (c
))
4141 /* A conversion function is OK. If it isn't constexpr, we'll
4142 complain later that the argument isn't constant. */
4144 /* The lvalue-to-rvalue conversion is OK. */
4146 /* Array-to-pointer and function-to-pointer. */
4148 /* Function pointer conversions. */
4150 /* Qualification conversions. */
4155 if (c
->need_temporary_p
)
4157 if (complain
& tf_error
)
4158 error_at (loc
, "initializing %qH with %qI in converted "
4159 "constant expression does not bind directly",
4160 type
, next_conversion (c
)->type
);
4169 t
= next_conversion (c
)->type
;
4170 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t
)
4171 && INTEGRAL_OR_ENUMERATION_TYPE_P (type
))
4172 /* Integral promotion or conversion. */
4174 if (NULLPTR_TYPE_P (t
))
4175 /* Conversion from nullptr to pointer or pointer-to-member. */
4178 if (complain
& tf_error
)
4179 error_at (loc
, "conversion from %qH to %qI in a "
4180 "converted constant expression", t
, type
);
4189 /* Avoid confusing convert_nontype_argument by introducing
4190 a redundant conversion to the same reference type. */
4191 if (conv
&& conv
->kind
== ck_ref_bind
4192 && REFERENCE_REF_P (expr
))
4194 tree ref
= TREE_OPERAND (expr
, 0);
4195 if (same_type_p (type
, TREE_TYPE (ref
)))
4201 conv
->check_narrowing
= true;
4202 conv
->check_narrowing_const_only
= true;
4203 expr
= convert_like (conv
, expr
, complain
);
4207 if (complain
& tf_error
)
4208 error_at (loc
, "could not convert %qE from %qH to %qI", expr
,
4209 TREE_TYPE (expr
), type
);
4210 expr
= error_mark_node
;
4213 /* Free all the conversions we allocated. */
4214 obstack_free (&conversion_obstack
, p
);
4219 /* Do any initial processing on the arguments to a function call. */
4221 static vec
<tree
, va_gc
> *
4222 resolve_args (vec
<tree
, va_gc
> *args
, tsubst_flags_t complain
)
4227 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
4229 if (error_operand_p (arg
))
4231 else if (VOID_TYPE_P (TREE_TYPE (arg
)))
4233 if (complain
& tf_error
)
4234 error ("invalid use of void expression");
4237 else if (invalid_nonstatic_memfn_p (arg
->exp
.locus
, arg
, complain
))
4243 /* Perform overload resolution on FN, which is called with the ARGS.
4245 Return the candidate function selected by overload resolution, or
4246 NULL if the event that overload resolution failed. In the case
4247 that overload resolution fails, *CANDIDATES will be the set of
4248 candidates considered, and ANY_VIABLE_P will be set to true or
4249 false to indicate whether or not any of the candidates were
4252 The ARGS should already have gone through RESOLVE_ARGS before this
4253 function is called. */
4255 static struct z_candidate
*
4256 perform_overload_resolution (tree fn
,
4257 const vec
<tree
, va_gc
> *args
,
4258 struct z_candidate
**candidates
,
4259 bool *any_viable_p
, tsubst_flags_t complain
)
4261 struct z_candidate
*cand
;
4262 tree explicit_targs
;
4265 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4267 explicit_targs
= NULL_TREE
;
4271 *any_viable_p
= true;
4274 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
4275 || TREE_CODE (fn
) == TEMPLATE_DECL
4276 || TREE_CODE (fn
) == OVERLOAD
4277 || TREE_CODE (fn
) == TEMPLATE_ID_EXPR
);
4279 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4281 explicit_targs
= TREE_OPERAND (fn
, 1);
4282 fn
= TREE_OPERAND (fn
, 0);
4286 /* Add the various candidate functions. */
4287 add_candidates (fn
, NULL_TREE
, args
, NULL_TREE
,
4288 explicit_targs
, template_only
,
4289 /*conversion_path=*/NULL_TREE
,
4290 /*access_path=*/NULL_TREE
,
4292 candidates
, complain
);
4294 *candidates
= splice_viable (*candidates
, false, any_viable_p
);
4296 cand
= tourney (*candidates
, complain
);
4300 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4304 /* Print an error message about being unable to build a call to FN with
4305 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4306 be located; CANDIDATES is a possibly empty list of such
4310 print_error_for_call_failure (tree fn
, vec
<tree
, va_gc
> *args
,
4311 struct z_candidate
*candidates
)
4313 tree targs
= NULL_TREE
;
4314 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4316 targs
= TREE_OPERAND (fn
, 1);
4317 fn
= TREE_OPERAND (fn
, 0);
4319 tree name
= OVL_NAME (fn
);
4320 location_t loc
= location_of (name
);
4322 name
= lookup_template_function (name
, targs
);
4324 auto_diagnostic_group d
;
4325 if (!any_strictly_viable (candidates
))
4326 error_at (loc
, "no matching function for call to %<%D(%A)%>",
4327 name
, build_tree_list_vec (args
));
4329 error_at (loc
, "call of overloaded %<%D(%A)%> is ambiguous",
4330 name
, build_tree_list_vec (args
));
4332 print_z_candidates (loc
, candidates
);
4335 /* Return an expression for a call to FN (a namespace-scope function,
4336 or a static member function) with the ARGS. This may change
4340 build_new_function_call (tree fn
, vec
<tree
, va_gc
> **args
,
4341 tsubst_flags_t complain
)
4343 struct z_candidate
*candidates
, *cand
;
4348 if (args
!= NULL
&& *args
!= NULL
)
4350 *args
= resolve_args (*args
, complain
);
4352 return error_mark_node
;
4356 tm_malloc_replacement (fn
);
4358 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4359 p
= conversion_obstack_alloc (0);
4361 cand
= perform_overload_resolution (fn
, *args
, &candidates
, &any_viable_p
,
4366 if (complain
& tf_error
)
4368 // If there is a single (non-viable) function candidate,
4369 // let the error be diagnosed by cp_build_function_call_vec.
4370 if (!any_viable_p
&& candidates
&& ! candidates
->next
4371 && (TREE_CODE (candidates
->fn
) == FUNCTION_DECL
))
4372 return cp_build_function_call_vec (candidates
->fn
, args
, complain
);
4374 // Otherwise, emit notes for non-viable candidates.
4375 print_error_for_call_failure (fn
, *args
, candidates
);
4377 result
= error_mark_node
;
4381 int flags
= LOOKUP_NORMAL
;
4382 /* If fn is template_id_expr, the call has explicit template arguments
4383 (e.g. func<int>(5)), communicate this info to build_over_call
4384 through flags so that later we can use it to decide whether to warn
4385 about peculiar null pointer conversion. */
4386 if (TREE_CODE (fn
) == TEMPLATE_ID_EXPR
)
4388 /* If overload resolution selects a specialization of a
4389 function concept for non-dependent template arguments,
4390 the expression is true if the constraints are satisfied
4391 and false otherwise.
4393 NOTE: This is an extension of Concepts Lite TS that
4394 allows constraints to be used in expressions. */
4395 if (flag_concepts
&& !processing_template_decl
)
4397 tree tmpl
= DECL_TI_TEMPLATE (cand
->fn
);
4398 tree targs
= DECL_TI_ARGS (cand
->fn
);
4399 tree decl
= DECL_TEMPLATE_RESULT (tmpl
);
4400 if (DECL_DECLARED_CONCEPT_P (decl
))
4401 return evaluate_function_concept (decl
, targs
);
4404 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
4407 result
= build_over_call (cand
, flags
, complain
);
4410 /* Free all the conversions we allocated. */
4411 obstack_free (&conversion_obstack
, p
);
4416 /* Build a call to a global operator new. FNNAME is the name of the
4417 operator (either "operator new" or "operator new[]") and ARGS are
4418 the arguments provided. This may change ARGS. *SIZE points to the
4419 total number of bytes required by the allocation, and is updated if
4420 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4421 be used. If this function determines that no cookie should be
4422 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4423 is not NULL_TREE, it is evaluated before calculating the final
4424 array size, and if it fails, the array size is replaced with
4425 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4426 is non-NULL, it will be set, upon return, to the allocation
4430 build_operator_new_call (tree fnname
, vec
<tree
, va_gc
> **args
,
4431 tree
*size
, tree
*cookie_size
,
4432 tree align_arg
, tree size_check
,
4433 tree
*fn
, tsubst_flags_t complain
)
4435 tree original_size
= *size
;
4437 struct z_candidate
*candidates
;
4438 struct z_candidate
*cand
= NULL
;
4443 /* Set to (size_t)-1 if the size check fails. */
4444 if (size_check
!= NULL_TREE
)
4446 tree errval
= TYPE_MAX_VALUE (sizetype
);
4447 if (cxx_dialect
>= cxx11
&& flag_exceptions
)
4448 errval
= throw_bad_array_new_length ();
4449 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4450 original_size
, errval
);
4452 vec_safe_insert (*args
, 0, *size
);
4453 *args
= resolve_args (*args
, complain
);
4455 return error_mark_node
;
4461 If this lookup fails to find the name, or if the allocated type
4462 is not a class type, the allocation function's name is looked
4463 up in the global scope.
4465 we disregard block-scope declarations of "operator new". */
4466 fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/false, 0, 0);
4467 fns
= lookup_arg_dependent (fnname
, fns
, *args
);
4471 vec
<tree
, va_gc
>* align_args
4472 = vec_copy_and_insert (*args
, align_arg
, 1);
4473 cand
= perform_overload_resolution (fns
, align_args
, &candidates
,
4474 &any_viable_p
, tf_none
);
4477 /* If no aligned allocation function matches, try again without the
4481 /* Figure out what function is being called. */
4483 cand
= perform_overload_resolution (fns
, *args
, &candidates
, &any_viable_p
,
4486 /* If no suitable function could be found, issue an error message
4490 if (complain
& tf_error
)
4491 print_error_for_call_failure (fns
, *args
, candidates
);
4492 return error_mark_node
;
4495 /* If a cookie is required, add some extra space. Whether
4496 or not a cookie is required cannot be determined until
4497 after we know which function was called. */
4500 bool use_cookie
= true;
4503 arg_types
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
4504 /* Skip the size_t parameter. */
4505 arg_types
= TREE_CHAIN (arg_types
);
4506 /* Check the remaining parameters (if any). */
4508 && TREE_CHAIN (arg_types
) == void_list_node
4509 && same_type_p (TREE_VALUE (arg_types
),
4512 /* If we need a cookie, adjust the number of bytes allocated. */
4515 /* Update the total size. */
4516 *size
= size_binop (PLUS_EXPR
, original_size
, *cookie_size
);
4519 /* Set to (size_t)-1 if the size check fails. */
4520 gcc_assert (size_check
!= NULL_TREE
);
4521 *size
= fold_build3 (COND_EXPR
, sizetype
, size_check
,
4522 *size
, TYPE_MAX_VALUE (sizetype
));
4524 /* Update the argument list to reflect the adjusted size. */
4525 (**args
)[0] = *size
;
4528 *cookie_size
= NULL_TREE
;
4531 /* Tell our caller which function we decided to call. */
4535 /* Build the CALL_EXPR. */
4536 return build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4539 /* Build a new call to operator(). This may change ARGS. */
4542 build_op_call_1 (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4544 struct z_candidate
*candidates
= 0, *cand
;
4545 tree fns
, convs
, first_mem_arg
= NULL_TREE
;
4547 tree result
= NULL_TREE
;
4550 obj
= mark_lvalue_use (obj
);
4552 if (error_operand_p (obj
))
4553 return error_mark_node
;
4555 tree type
= TREE_TYPE (obj
);
4557 obj
= prep_operand (obj
);
4559 if (TYPE_PTRMEMFUNC_P (type
))
4561 if (complain
& tf_error
)
4562 /* It's no good looking for an overloaded operator() on a
4563 pointer-to-member-function. */
4564 error ("pointer-to-member function %qE cannot be called without "
4565 "an object; consider using %<.*%> or %<->*%>", obj
);
4566 return error_mark_node
;
4569 if (TYPE_BINFO (type
))
4571 fns
= lookup_fnfields (TYPE_BINFO (type
), call_op_identifier
, 1);
4572 if (fns
== error_mark_node
)
4573 return error_mark_node
;
4578 if (args
!= NULL
&& *args
!= NULL
)
4580 *args
= resolve_args (*args
, complain
);
4582 return error_mark_node
;
4585 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4586 p
= conversion_obstack_alloc (0);
4590 first_mem_arg
= obj
;
4592 add_candidates (BASELINK_FUNCTIONS (fns
),
4593 first_mem_arg
, *args
, NULL_TREE
,
4595 BASELINK_BINFO (fns
), BASELINK_ACCESS_BINFO (fns
),
4596 LOOKUP_NORMAL
, &candidates
, complain
);
4599 convs
= lookup_conversions (type
);
4601 for (; convs
; convs
= TREE_CHAIN (convs
))
4603 tree totype
= TREE_TYPE (convs
);
4605 if (TYPE_PTRFN_P (totype
)
4606 || TYPE_REFFN_P (totype
)
4607 || (TYPE_REF_P (totype
)
4608 && TYPE_PTRFN_P (TREE_TYPE (totype
))))
4609 for (ovl_iterator
iter (TREE_VALUE (convs
)); iter
; ++iter
)
4613 if (DECL_NONCONVERTING_P (fn
))
4616 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
4617 add_template_conv_candidate
4618 (&candidates
, fn
, obj
, *args
, totype
,
4619 /*access_path=*/NULL_TREE
,
4620 /*conversion_path=*/NULL_TREE
, complain
);
4622 add_conv_candidate (&candidates
, fn
, obj
,
4623 *args
, /*conversion_path=*/NULL_TREE
,
4624 /*access_path=*/NULL_TREE
, complain
);
4628 /* Be strict here because if we choose a bad conversion candidate, the
4629 errors we get won't mention the call context. */
4630 candidates
= splice_viable (candidates
, true, &any_viable_p
);
4633 if (complain
& tf_error
)
4635 auto_diagnostic_group d
;
4636 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj
),
4637 build_tree_list_vec (*args
));
4638 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4640 result
= error_mark_node
;
4644 cand
= tourney (candidates
, complain
);
4647 if (complain
& tf_error
)
4649 auto_diagnostic_group d
;
4650 error ("call of %<(%T) (%A)%> is ambiguous",
4651 TREE_TYPE (obj
), build_tree_list_vec (*args
));
4652 print_z_candidates (location_of (TREE_TYPE (obj
)), candidates
);
4654 result
= error_mark_node
;
4656 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
4657 && DECL_OVERLOADED_OPERATOR_P (cand
->fn
)
4658 && DECL_OVERLOADED_OPERATOR_IS (cand
->fn
, CALL_EXPR
))
4659 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
4662 if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
4663 obj
= convert_like_with_context (cand
->convs
[0], obj
, cand
->fn
,
4667 gcc_checking_assert (TYPE_P (cand
->fn
));
4668 obj
= convert_like (cand
->convs
[0], obj
, complain
);
4670 obj
= convert_from_reference (obj
);
4671 result
= cp_build_function_call_vec (obj
, args
, complain
);
4675 /* Free all the conversions we allocated. */
4676 obstack_free (&conversion_obstack
, p
);
4681 /* Wrapper for above. */
4684 build_op_call (tree obj
, vec
<tree
, va_gc
> **args
, tsubst_flags_t complain
)
4687 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
4688 ret
= build_op_call_1 (obj
, args
, complain
);
4689 timevar_cond_stop (TV_OVERLOAD
, subtime
);
4693 /* Called by op_error to prepare format strings suitable for the error
4694 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4695 and a suffix (controlled by NTYPES). */
4698 op_error_string (const char *errmsg
, int ntypes
, bool match
)
4702 const char *msgp
= concat (match
? G_("ambiguous overload for ")
4703 : G_("no match for "), errmsg
, NULL
);
4706 msg
= concat (msgp
, G_(" (operand types are %qT, %qT, and %qT)"), NULL
);
4707 else if (ntypes
== 2)
4708 msg
= concat (msgp
, G_(" (operand types are %qT and %qT)"), NULL
);
4710 msg
= concat (msgp
, G_(" (operand type is %qT)"), NULL
);
4716 op_error (location_t loc
, enum tree_code code
, enum tree_code code2
,
4717 tree arg1
, tree arg2
, tree arg3
, bool match
)
4719 bool assop
= code
== MODIFY_EXPR
;
4720 const char *opname
= OVL_OP_INFO (assop
, assop
? code2
: code
)->name
;
4725 if (flag_diagnostics_show_caret
)
4726 error_at (loc
, op_error_string (G_("ternary %<operator?:%>"),
4728 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4730 error_at (loc
, op_error_string (G_("ternary %<operator?:%> "
4731 "in %<%E ? %E : %E%>"), 3, match
),
4733 TREE_TYPE (arg1
), TREE_TYPE (arg2
), TREE_TYPE (arg3
));
4736 case POSTINCREMENT_EXPR
:
4737 case POSTDECREMENT_EXPR
:
4738 if (flag_diagnostics_show_caret
)
4739 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4740 opname
, TREE_TYPE (arg1
));
4742 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4744 opname
, arg1
, opname
, TREE_TYPE (arg1
));
4748 if (flag_diagnostics_show_caret
)
4749 error_at (loc
, op_error_string (G_("%<operator[]%>"), 2, match
),
4750 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4752 error_at (loc
, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4754 arg1
, arg2
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4759 if (flag_diagnostics_show_caret
)
4760 error_at (loc
, op_error_string (G_("%qs"), 1, match
),
4761 opname
, TREE_TYPE (arg1
));
4763 error_at (loc
, op_error_string (G_("%qs in %<%s %E%>"), 1, match
),
4764 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4769 if (flag_diagnostics_show_caret
)
4770 error_at (loc
, op_error_string (G_("%<operator%s%>"), 2, match
),
4771 opname
, TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4773 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4775 opname
, arg1
, opname
, arg2
,
4776 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
4778 if (flag_diagnostics_show_caret
)
4779 error_at (loc
, op_error_string (G_("%<operator%s%>"), 1, match
),
4780 opname
, TREE_TYPE (arg1
));
4782 error_at (loc
, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4784 opname
, opname
, arg1
, TREE_TYPE (arg1
));
4789 /* Return the implicit conversion sequence that could be used to
4790 convert E1 to E2 in [expr.cond]. */
4793 conditional_conversion (tree e1
, tree e2
, tsubst_flags_t complain
)
4795 tree t1
= non_reference (TREE_TYPE (e1
));
4796 tree t2
= non_reference (TREE_TYPE (e2
));
4802 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4803 implicitly converted (clause _conv_) to the type "lvalue reference to
4804 T2", subject to the constraint that in the conversion the
4805 reference must bind directly (_dcl.init.ref_) to an lvalue.
4807 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4808 implicitly converted to the type "rvalue reference to T2", subject to
4809 the constraint that the reference must bind directly. */
4812 tree rtype
= cp_build_reference_type (t2
, !lvalue_p (e2
));
4813 conv
= implicit_conversion (rtype
,
4817 LOOKUP_NO_TEMP_BIND
|LOOKUP_NO_RVAL_BIND
4818 |LOOKUP_ONLYCONVERTING
,
4820 if (conv
&& !conv
->bad_p
)
4824 /* If E2 is a prvalue or if neither of the conversions above can be done
4825 and at least one of the operands has (possibly cv-qualified) class
4827 if (!CLASS_TYPE_P (t1
) && !CLASS_TYPE_P (t2
))
4832 If E1 and E2 have class type, and the underlying class types are
4833 the same or one is a base class of the other: E1 can be converted
4834 to match E2 if the class of T2 is the same type as, or a base
4835 class of, the class of T1, and the cv-qualification of T2 is the
4836 same cv-qualification as, or a greater cv-qualification than, the
4837 cv-qualification of T1. If the conversion is applied, E1 is
4838 changed to an rvalue of type T2 that still refers to the original
4839 source class object (or the appropriate subobject thereof). */
4840 if (CLASS_TYPE_P (t1
) && CLASS_TYPE_P (t2
)
4841 && ((good_base
= DERIVED_FROM_P (t2
, t1
)) || DERIVED_FROM_P (t1
, t2
)))
4843 if (good_base
&& at_least_as_qualified_p (t2
, t1
))
4845 conv
= build_identity_conv (t1
, e1
);
4846 if (!same_type_p (TYPE_MAIN_VARIANT (t1
),
4847 TYPE_MAIN_VARIANT (t2
)))
4848 conv
= build_conv (ck_base
, t2
, conv
);
4850 conv
= build_conv (ck_rvalue
, t2
, conv
);
4859 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4860 converted to the type that expression E2 would have if E2 were
4861 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4862 return implicit_conversion (t2
, t1
, e1
, /*c_cast_p=*/false,
4863 LOOKUP_IMPLICIT
, complain
);
4866 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4867 arguments to the conditional expression. */
4870 build_conditional_expr_1 (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
4871 tsubst_flags_t complain
)
4875 tree result
= NULL_TREE
;
4876 tree result_type
= NULL_TREE
;
4877 bool is_glvalue
= true;
4878 struct z_candidate
*candidates
= 0;
4879 struct z_candidate
*cand
;
4881 tree orig_arg2
, orig_arg3
;
4883 /* As a G++ extension, the second argument to the conditional can be
4884 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4885 c'.) If the second operand is omitted, make sure it is
4886 calculated only once. */
4889 if (complain
& tf_error
)
4890 pedwarn (loc
, OPT_Wpedantic
,
4891 "ISO C++ forbids omitting the middle term of a ?: expression");
4893 if ((complain
& tf_warning
) && !truth_value_p (TREE_CODE (arg1
)))
4894 warn_for_omitted_condop (loc
, arg1
);
4896 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4897 if (lvalue_p (arg1
))
4898 arg2
= arg1
= cp_stabilize_reference (arg1
);
4900 arg2
= arg1
= cp_save_expr (arg1
);
4903 /* If something has already gone wrong, just pass that fact up the
4905 if (error_operand_p (arg1
)
4906 || error_operand_p (arg2
)
4907 || error_operand_p (arg3
))
4908 return error_mark_node
;
4913 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1
)))
4915 tree arg1_type
= TREE_TYPE (arg1
);
4917 /* If arg1 is another cond_expr choosing between -1 and 0,
4918 then we can use its comparison. It may help to avoid
4919 additional comparison, produce more accurate diagnostics
4920 and enables folding. */
4921 if (TREE_CODE (arg1
) == VEC_COND_EXPR
4922 && integer_minus_onep (TREE_OPERAND (arg1
, 1))
4923 && integer_zerop (TREE_OPERAND (arg1
, 2)))
4924 arg1
= TREE_OPERAND (arg1
, 0);
4926 arg1
= force_rvalue (arg1
, complain
);
4927 arg2
= force_rvalue (arg2
, complain
);
4928 arg3
= force_rvalue (arg3
, complain
);
4930 /* force_rvalue can return error_mark on valid arguments. */
4931 if (error_operand_p (arg1
)
4932 || error_operand_p (arg2
)
4933 || error_operand_p (arg3
))
4934 return error_mark_node
;
4936 arg2_type
= TREE_TYPE (arg2
);
4937 arg3_type
= TREE_TYPE (arg3
);
4939 if (!VECTOR_TYPE_P (arg2_type
)
4940 && !VECTOR_TYPE_P (arg3_type
))
4942 /* Rely on the error messages of the scalar version. */
4943 tree scal
= build_conditional_expr_1 (loc
, integer_one_node
,
4944 orig_arg2
, orig_arg3
, complain
);
4945 if (scal
== error_mark_node
)
4946 return error_mark_node
;
4947 tree stype
= TREE_TYPE (scal
);
4948 tree ctype
= TREE_TYPE (arg1_type
);
4949 if (TYPE_SIZE (stype
) != TYPE_SIZE (ctype
)
4950 || (!INTEGRAL_TYPE_P (stype
) && !SCALAR_FLOAT_TYPE_P (stype
)))
4952 if (complain
& tf_error
)
4953 error_at (loc
, "inferred scalar type %qT is not an integer or "
4954 "floating point type of the same size as %qT", stype
,
4955 COMPARISON_CLASS_P (arg1
)
4956 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1
, 0)))
4958 return error_mark_node
;
4961 tree vtype
= build_opaque_vector_type (stype
,
4962 TYPE_VECTOR_SUBPARTS (arg1_type
));
4963 /* We could pass complain & tf_warning to unsafe_conversion_p,
4964 but the warnings (like Wsign-conversion) have already been
4965 given by the scalar build_conditional_expr_1. We still check
4966 unsafe_conversion_p to forbid truncating long long -> float. */
4967 if (unsafe_conversion_p (loc
, stype
, arg2
, NULL_TREE
, false))
4969 if (complain
& tf_error
)
4970 error_at (loc
, "conversion of scalar %qH to vector %qI "
4971 "involves truncation", arg2_type
, vtype
);
4972 return error_mark_node
;
4974 if (unsafe_conversion_p (loc
, stype
, arg3
, NULL_TREE
, false))
4976 if (complain
& tf_error
)
4977 error_at (loc
, "conversion of scalar %qH to vector %qI "
4978 "involves truncation", arg3_type
, vtype
);
4979 return error_mark_node
;
4982 arg2
= cp_convert (stype
, arg2
, complain
);
4983 arg2
= save_expr (arg2
);
4984 arg2
= build_vector_from_val (vtype
, arg2
);
4986 arg3
= cp_convert (stype
, arg3
, complain
);
4987 arg3
= save_expr (arg3
);
4988 arg3
= build_vector_from_val (vtype
, arg3
);
4992 if (VECTOR_TYPE_P (arg2_type
) != VECTOR_TYPE_P (arg3_type
))
4994 enum stv_conv convert_flag
=
4995 scalar_to_vector (loc
, VEC_COND_EXPR
, arg2
, arg3
,
4996 complain
& tf_error
);
4998 switch (convert_flag
)
5001 return error_mark_node
;
5004 arg2
= save_expr (arg2
);
5005 arg2
= convert (TREE_TYPE (arg3_type
), arg2
);
5006 arg2
= build_vector_from_val (arg3_type
, arg2
);
5007 arg2_type
= TREE_TYPE (arg2
);
5012 arg3
= save_expr (arg3
);
5013 arg3
= convert (TREE_TYPE (arg2_type
), arg3
);
5014 arg3
= build_vector_from_val (arg2_type
, arg3
);
5015 arg3_type
= TREE_TYPE (arg3
);
5023 if (!same_type_p (arg2_type
, arg3_type
)
5024 || maybe_ne (TYPE_VECTOR_SUBPARTS (arg1_type
),
5025 TYPE_VECTOR_SUBPARTS (arg2_type
))
5026 || TYPE_SIZE (arg1_type
) != TYPE_SIZE (arg2_type
))
5028 if (complain
& tf_error
)
5030 "incompatible vector types in conditional expression: "
5031 "%qT, %qT and %qT", TREE_TYPE (arg1
),
5032 TREE_TYPE (orig_arg2
), TREE_TYPE (orig_arg3
));
5033 return error_mark_node
;
5036 if (!COMPARISON_CLASS_P (arg1
))
5038 tree cmp_type
= build_same_sized_truth_vector_type (arg1_type
);
5039 arg1
= build2 (NE_EXPR
, cmp_type
, arg1
, build_zero_cst (arg1_type
));
5041 return build3_loc (loc
, VEC_COND_EXPR
, arg2_type
, arg1
, arg2
, arg3
);
5046 The first expression is implicitly converted to bool (clause
5048 arg1
= perform_implicit_conversion_flags (boolean_type_node
, arg1
, complain
,
5050 if (error_operand_p (arg1
))
5051 return error_mark_node
;
5055 If either the second or the third operand has type (possibly
5056 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
5057 array-to-pointer (_conv.array_), and function-to-pointer
5058 (_conv.func_) standard conversions are performed on the second
5059 and third operands. */
5060 arg2_type
= unlowered_expr_type (arg2
);
5061 arg3_type
= unlowered_expr_type (arg3
);
5062 if (VOID_TYPE_P (arg2_type
) || VOID_TYPE_P (arg3_type
))
5066 One of the following shall hold:
5068 --The second or the third operand (but not both) is a
5069 throw-expression (_except.throw_); the result is of the type
5070 and value category of the other.
5072 --Both the second and the third operands have type void; the
5073 result is of type void and is a prvalue. */
5074 if (TREE_CODE (arg2
) == THROW_EXPR
5075 && TREE_CODE (arg3
) != THROW_EXPR
)
5077 result_type
= arg3_type
;
5078 is_glvalue
= glvalue_p (arg3
);
5080 else if (TREE_CODE (arg2
) != THROW_EXPR
5081 && TREE_CODE (arg3
) == THROW_EXPR
)
5083 result_type
= arg2_type
;
5084 is_glvalue
= glvalue_p (arg2
);
5086 else if (VOID_TYPE_P (arg2_type
) && VOID_TYPE_P (arg3_type
))
5088 result_type
= void_type_node
;
5093 if (complain
& tf_error
)
5095 if (VOID_TYPE_P (arg2_type
))
5096 error_at (cp_expr_loc_or_loc (arg3
, loc
),
5097 "second operand to the conditional operator "
5098 "is of type %<void%>, but the third operand is "
5099 "neither a throw-expression nor of type %<void%>");
5101 error_at (cp_expr_loc_or_loc (arg2
, loc
),
5102 "third operand to the conditional operator "
5103 "is of type %<void%>, but the second operand is "
5104 "neither a throw-expression nor of type %<void%>");
5106 return error_mark_node
;
5109 goto valid_operands
;
5113 Otherwise, if the second and third operand have different types,
5114 and either has (possibly cv-qualified) class type, or if both are
5115 glvalues of the same value category and the same type except for
5116 cv-qualification, an attempt is made to convert each of those operands
5117 to the type of the other. */
5118 else if (!same_type_p (arg2_type
, arg3_type
)
5119 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)
5120 || (same_type_ignoring_top_level_qualifiers_p (arg2_type
,
5122 && glvalue_p (arg2
) && glvalue_p (arg3
)
5123 && lvalue_p (arg2
) == lvalue_p (arg3
))))
5127 bool converted
= false;
5129 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5130 p
= conversion_obstack_alloc (0);
5132 conv2
= conditional_conversion (arg2
, arg3
, complain
);
5133 conv3
= conditional_conversion (arg3
, arg2
, complain
);
5137 If both can be converted, or one can be converted but the
5138 conversion is ambiguous, the program is ill-formed. If
5139 neither can be converted, the operands are left unchanged and
5140 further checking is performed as described below. If exactly
5141 one conversion is possible, that conversion is applied to the
5142 chosen operand and the converted operand is used in place of
5143 the original operand for the remainder of this section. */
5144 if ((conv2
&& !conv2
->bad_p
5145 && conv3
&& !conv3
->bad_p
)
5146 || (conv2
&& conv2
->kind
== ck_ambig
)
5147 || (conv3
&& conv3
->kind
== ck_ambig
))
5149 if (complain
& tf_error
)
5151 error_at (loc
, "operands to ?: have different types %qT and %qT",
5152 arg2_type
, arg3_type
);
5153 if (conv2
&& !conv2
->bad_p
&& conv3
&& !conv3
->bad_p
)
5154 inform (loc
, " and each type can be converted to the other");
5155 else if (conv2
&& conv2
->kind
== ck_ambig
)
5156 convert_like (conv2
, arg2
, complain
);
5158 convert_like (conv3
, arg3
, complain
);
5160 result
= error_mark_node
;
5162 else if (conv2
&& !conv2
->bad_p
)
5164 arg2
= convert_like (conv2
, arg2
, complain
);
5165 arg2
= convert_from_reference (arg2
);
5166 arg2_type
= TREE_TYPE (arg2
);
5167 /* Even if CONV2 is a valid conversion, the result of the
5168 conversion may be invalid. For example, if ARG3 has type
5169 "volatile X", and X does not have a copy constructor
5170 accepting a "volatile X&", then even if ARG2 can be
5171 converted to X, the conversion will fail. */
5172 if (error_operand_p (arg2
))
5173 result
= error_mark_node
;
5176 else if (conv3
&& !conv3
->bad_p
)
5178 arg3
= convert_like (conv3
, arg3
, complain
);
5179 arg3
= convert_from_reference (arg3
);
5180 arg3_type
= TREE_TYPE (arg3
);
5181 if (error_operand_p (arg3
))
5182 result
= error_mark_node
;
5186 /* Free all the conversions we allocated. */
5187 obstack_free (&conversion_obstack
, p
);
5192 /* If, after the conversion, both operands have class type,
5193 treat the cv-qualification of both operands as if it were the
5194 union of the cv-qualification of the operands.
5196 The standard is not clear about what to do in this
5197 circumstance. For example, if the first operand has type
5198 "const X" and the second operand has a user-defined
5199 conversion to "volatile X", what is the type of the second
5200 operand after this step? Making it be "const X" (matching
5201 the first operand) seems wrong, as that discards the
5202 qualification without actually performing a copy. Leaving it
5203 as "volatile X" seems wrong as that will result in the
5204 conditional expression failing altogether, even though,
5205 according to this step, the one operand could be converted to
5206 the type of the other. */
5208 && CLASS_TYPE_P (arg2_type
)
5209 && cp_type_quals (arg2_type
) != cp_type_quals (arg3_type
))
5210 arg2_type
= arg3_type
=
5211 cp_build_qualified_type (arg2_type
,
5212 cp_type_quals (arg2_type
)
5213 | cp_type_quals (arg3_type
));
5218 If the second and third operands are glvalues of the same value
5219 category and have the same type, the result is of that type and
5221 if (((lvalue_p (arg2
) && lvalue_p (arg3
))
5222 || (xvalue_p (arg2
) && xvalue_p (arg3
)))
5223 && same_type_p (arg2_type
, arg3_type
))
5225 result_type
= arg2_type
;
5226 arg2
= mark_lvalue_use (arg2
);
5227 arg3
= mark_lvalue_use (arg3
);
5228 goto valid_operands
;
5233 Otherwise, the result is an rvalue. If the second and third
5234 operand do not have the same type, and either has (possibly
5235 cv-qualified) class type, overload resolution is used to
5236 determine the conversions (if any) to be applied to the operands
5237 (_over.match.oper_, _over.built_). */
5239 if (!same_type_p (arg2_type
, arg3_type
)
5240 && (CLASS_TYPE_P (arg2_type
) || CLASS_TYPE_P (arg3_type
)))
5246 /* Rearrange the arguments so that add_builtin_candidate only has
5247 to know about two args. In build_builtin_candidate, the
5248 arguments are unscrambled. */
5252 add_builtin_candidates (&candidates
,
5255 ovl_op_identifier (false, COND_EXPR
),
5257 LOOKUP_NORMAL
, complain
);
5261 If the overload resolution fails, the program is
5263 candidates
= splice_viable (candidates
, false, &any_viable_p
);
5266 if (complain
& tf_error
)
5267 error_at (loc
, "operands to ?: have different types %qT and %qT",
5268 arg2_type
, arg3_type
);
5269 return error_mark_node
;
5271 cand
= tourney (candidates
, complain
);
5274 if (complain
& tf_error
)
5276 auto_diagnostic_group d
;
5277 op_error (loc
, COND_EXPR
, NOP_EXPR
, arg1
, arg2
, arg3
, FALSE
);
5278 print_z_candidates (loc
, candidates
);
5280 return error_mark_node
;
5285 Otherwise, the conversions thus determined are applied, and
5286 the converted operands are used in place of the original
5287 operands for the remainder of this section. */
5288 conv
= cand
->convs
[0];
5289 arg1
= convert_like (conv
, arg1
, complain
);
5290 conv
= cand
->convs
[1];
5291 arg2
= convert_like (conv
, arg2
, complain
);
5292 arg2_type
= TREE_TYPE (arg2
);
5293 conv
= cand
->convs
[2];
5294 arg3
= convert_like (conv
, arg3
, complain
);
5295 arg3_type
= TREE_TYPE (arg3
);
5300 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
5301 and function-to-pointer (_conv.func_) standard conversions are
5302 performed on the second and third operands.
5304 We need to force the lvalue-to-rvalue conversion here for class types,
5305 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5306 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5309 arg2
= force_rvalue (arg2
, complain
);
5310 if (!CLASS_TYPE_P (arg2_type
))
5311 arg2_type
= TREE_TYPE (arg2
);
5313 arg3
= force_rvalue (arg3
, complain
);
5314 if (!CLASS_TYPE_P (arg3_type
))
5315 arg3_type
= TREE_TYPE (arg3
);
5317 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5318 return error_mark_node
;
5322 After those conversions, one of the following shall hold:
5324 --The second and third operands have the same type; the result is of
5326 if (same_type_p (arg2_type
, arg3_type
))
5327 result_type
= arg2_type
;
5330 --The second and third operands have arithmetic or enumeration
5331 type; the usual arithmetic conversions are performed to bring
5332 them to a common type, and the result is of that type. */
5333 else if ((ARITHMETIC_TYPE_P (arg2_type
)
5334 || UNSCOPED_ENUM_P (arg2_type
))
5335 && (ARITHMETIC_TYPE_P (arg3_type
)
5336 || UNSCOPED_ENUM_P (arg3_type
)))
5338 /* In this case, there is always a common type. */
5339 result_type
= type_after_usual_arithmetic_conversions (arg2_type
,
5341 if (complain
& tf_warning
)
5342 do_warn_double_promotion (result_type
, arg2_type
, arg3_type
,
5343 "implicit conversion from %qH to %qI to "
5344 "match other result of conditional",
5347 if (TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5348 && TREE_CODE (arg3_type
) == ENUMERAL_TYPE
)
5350 if (TREE_CODE (orig_arg2
) == CONST_DECL
5351 && TREE_CODE (orig_arg3
) == CONST_DECL
5352 && DECL_CONTEXT (orig_arg2
) == DECL_CONTEXT (orig_arg3
))
5353 /* Two enumerators from the same enumeration can have different
5354 types when the enumeration is still being defined. */;
5355 else if (complain
& tf_warning
)
5356 warning_at (loc
, OPT_Wenum_compare
, "enumeral mismatch in "
5357 "conditional expression: %qT vs %qT",
5358 arg2_type
, arg3_type
);
5360 else if (extra_warnings
5361 && ((TREE_CODE (arg2_type
) == ENUMERAL_TYPE
5362 && !same_type_p (arg3_type
, type_promotes_to (arg2_type
)))
5363 || (TREE_CODE (arg3_type
) == ENUMERAL_TYPE
5364 && !same_type_p (arg2_type
,
5365 type_promotes_to (arg3_type
)))))
5367 if (complain
& tf_warning
)
5368 warning_at (loc
, OPT_Wextra
, "enumeral and non-enumeral type in "
5369 "conditional expression");
5372 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5373 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5377 --The second and third operands have pointer type, or one has
5378 pointer type and the other is a null pointer constant; pointer
5379 conversions (_conv.ptr_) and qualification conversions
5380 (_conv.qual_) are performed to bring them to their composite
5381 pointer type (_expr.rel_). The result is of the composite
5384 --The second and third operands have pointer to member type, or
5385 one has pointer to member type and the other is a null pointer
5386 constant; pointer to member conversions (_conv.mem_) and
5387 qualification conversions (_conv.qual_) are performed to bring
5388 them to a common type, whose cv-qualification shall match the
5389 cv-qualification of either the second or the third operand.
5390 The result is of the common type. */
5391 else if ((null_ptr_cst_p (arg2
)
5392 && TYPE_PTR_OR_PTRMEM_P (arg3_type
))
5393 || (null_ptr_cst_p (arg3
)
5394 && TYPE_PTR_OR_PTRMEM_P (arg2_type
))
5395 || (TYPE_PTR_P (arg2_type
) && TYPE_PTR_P (arg3_type
))
5396 || (TYPE_PTRDATAMEM_P (arg2_type
) && TYPE_PTRDATAMEM_P (arg3_type
))
5397 || (TYPE_PTRMEMFUNC_P (arg2_type
) && TYPE_PTRMEMFUNC_P (arg3_type
)))
5399 result_type
= composite_pointer_type (arg2_type
, arg3_type
, arg2
,
5400 arg3
, CPO_CONDITIONAL_EXPR
,
5402 if (result_type
== error_mark_node
)
5403 return error_mark_node
;
5404 arg2
= perform_implicit_conversion (result_type
, arg2
, complain
);
5405 arg3
= perform_implicit_conversion (result_type
, arg3
, complain
);
5410 if (complain
& tf_error
)
5411 error_at (loc
, "operands to ?: have different types %qT and %qT",
5412 arg2_type
, arg3_type
);
5413 return error_mark_node
;
5416 if (arg2
== error_mark_node
|| arg3
== error_mark_node
)
5417 return error_mark_node
;
5420 if (processing_template_decl
&& is_glvalue
)
5422 /* Let lvalue_kind know this was a glvalue. */
5423 tree arg
= (result_type
== arg2_type
? arg2
: arg3
);
5424 result_type
= cp_build_reference_type (result_type
, xvalue_p (arg
));
5427 result
= build3_loc (loc
, COND_EXPR
, result_type
, arg1
, arg2
, arg3
);
5429 /* If the ARG2 and ARG3 are the same and don't have side-effects,
5430 warn here, because the COND_EXPR will be turned into ARG2. */
5431 if (warn_duplicated_branches
5432 && (complain
& tf_warning
)
5433 && (arg2
== arg3
|| operand_equal_p (arg2
, arg3
, 0)))
5434 warning_at (EXPR_LOCATION (result
), OPT_Wduplicated_branches
,
5435 "this condition has identical branches");
5437 /* We can't use result_type below, as fold might have returned a
5442 /* Expand both sides into the same slot, hopefully the target of
5443 the ?: expression. We used to check for TARGET_EXPRs here,
5444 but now we sometimes wrap them in NOP_EXPRs so the test would
5446 if (CLASS_TYPE_P (TREE_TYPE (result
)))
5447 result
= get_target_expr_sfinae (result
, complain
);
5448 /* If this expression is an rvalue, but might be mistaken for an
5449 lvalue, we must add a NON_LVALUE_EXPR. */
5450 result
= rvalue (result
);
5453 result
= force_paren_expr (result
);
5458 /* Wrapper for above. */
5461 build_conditional_expr (location_t loc
, tree arg1
, tree arg2
, tree arg3
,
5462 tsubst_flags_t complain
)
5465 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
5466 ret
= build_conditional_expr_1 (loc
, arg1
, arg2
, arg3
, complain
);
5467 timevar_cond_stop (TV_OVERLOAD
, subtime
);
5471 /* OPERAND is an operand to an expression. Perform necessary steps
5472 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5476 prep_operand (tree operand
)
5480 if (CLASS_TYPE_P (TREE_TYPE (operand
))
5481 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand
)))
5482 /* Make sure the template type is instantiated now. */
5483 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand
)));
5489 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5490 OVERLOAD) to the CANDIDATES, returning an updated list of
5491 CANDIDATES. The ARGS are the arguments provided to the call;
5492 if FIRST_ARG is non-null it is the implicit object argument,
5493 otherwise the first element of ARGS is used if needed. The
5494 EXPLICIT_TARGS are explicit template arguments provided.
5495 TEMPLATE_ONLY is true if only template functions should be
5496 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5497 add_function_candidate. */
5500 add_candidates (tree fns
, tree first_arg
, const vec
<tree
, va_gc
> *args
,
5502 tree explicit_targs
, bool template_only
,
5503 tree conversion_path
, tree access_path
,
5505 struct z_candidate
**candidates
,
5506 tsubst_flags_t complain
)
5509 const vec
<tree
, va_gc
> *non_static_args
;
5510 bool check_list_ctor
= false;
5511 bool check_converting
= false;
5512 unification_kind_t strict
;
5517 /* Precalculate special handling of constructors and conversion ops. */
5518 tree fn
= OVL_FIRST (fns
);
5519 if (DECL_CONV_FN_P (fn
))
5521 check_list_ctor
= false;
5522 check_converting
= (flags
& LOOKUP_ONLYCONVERTING
) != 0;
5523 if (flags
& LOOKUP_NO_CONVERSION
)
5524 /* We're doing return_type(x). */
5525 strict
= DEDUCE_CONV
;
5527 /* We're doing x.operator return_type(). */
5528 strict
= DEDUCE_EXACT
;
5529 /* [over.match.funcs] For conversion functions, the function
5530 is considered to be a member of the class of the implicit
5531 object argument for the purpose of defining the type of
5532 the implicit object parameter. */
5533 ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (first_arg
));
5537 if (DECL_CONSTRUCTOR_P (fn
))
5539 check_list_ctor
= (flags
& LOOKUP_LIST_ONLY
) != 0;
5540 /* For list-initialization we consider explicit constructors
5541 and complain if one is chosen. */
5543 = ((flags
& (LOOKUP_ONLYCONVERTING
|LOOKUP_LIST_INIT_CTOR
))
5544 == LOOKUP_ONLYCONVERTING
);
5546 strict
= DEDUCE_CALL
;
5547 ctype
= conversion_path
? BINFO_TYPE (conversion_path
) : NULL_TREE
;
5551 non_static_args
= args
;
5553 /* Delay creating the implicit this parameter until it is needed. */
5554 non_static_args
= NULL
;
5556 for (lkp_iterator
iter (fns
); iter
; ++iter
)
5560 if (check_converting
&& DECL_NONCONVERTING_P (fn
))
5562 if (check_list_ctor
&& !is_list_ctor (fn
))
5565 tree fn_first_arg
= NULL_TREE
;
5566 const vec
<tree
, va_gc
> *fn_args
= args
;
5568 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
5570 /* Figure out where the object arg comes from. If this
5571 function is a non-static member and we didn't get an
5572 implicit object argument, move it out of args. */
5573 if (first_arg
== NULL_TREE
)
5577 vec
<tree
, va_gc
> *tempvec
;
5578 vec_alloc (tempvec
, args
->length () - 1);
5579 for (ix
= 1; args
->iterate (ix
, &arg
); ++ix
)
5580 tempvec
->quick_push (arg
);
5581 non_static_args
= tempvec
;
5582 first_arg
= (*args
)[0];
5585 fn_first_arg
= first_arg
;
5586 fn_args
= non_static_args
;
5589 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
5590 add_template_candidate (candidates
,
5602 else if (!template_only
)
5603 add_function_candidate (candidates
,
5616 /* Returns 1 if P0145R2 says that the LHS of operator CODE is evaluated first,
5617 -1 if the RHS is evaluated first, or 0 if the order is unspecified. */
5620 op_is_ordered (tree_code code
)
5626 return (flag_strong_eval_order
> 1 ? -1 : 0);
5630 return (flag_strong_eval_order
> 1 ? 1 : 0);
5633 // Not overloadable (yet).
5635 // Only one argument.
5642 return (flag_strong_eval_order
? 1 : 0);
5650 build_new_op_1 (location_t loc
, enum tree_code code
, int flags
, tree arg1
,
5651 tree arg2
, tree arg3
, tree
*overload
, tsubst_flags_t complain
)
5653 struct z_candidate
*candidates
= 0, *cand
;
5654 vec
<tree
, va_gc
> *arglist
;
5656 tree result
= NULL_TREE
;
5657 bool result_valid_p
= false;
5658 enum tree_code code2
= NOP_EXPR
;
5659 enum tree_code code_orig_arg1
= ERROR_MARK
;
5660 enum tree_code code_orig_arg2
= ERROR_MARK
;
5666 if (error_operand_p (arg1
)
5667 || error_operand_p (arg2
)
5668 || error_operand_p (arg3
))
5669 return error_mark_node
;
5671 bool ismodop
= code
== MODIFY_EXPR
;
5674 code2
= TREE_CODE (arg3
);
5677 tree fnname
= ovl_op_identifier (ismodop
, ismodop
? code2
: code
);
5679 arg1
= prep_operand (arg1
);
5681 bool memonly
= false;
5686 case VEC_DELETE_EXPR
:
5688 /* Use build_op_new_call and build_op_delete_call instead. */
5692 /* Use build_op_call instead. */
5695 case TRUTH_ORIF_EXPR
:
5696 case TRUTH_ANDIF_EXPR
:
5697 case TRUTH_AND_EXPR
:
5699 /* These are saved for the sake of warn_logical_operator. */
5700 code_orig_arg1
= TREE_CODE (arg1
);
5701 code_orig_arg2
= TREE_CODE (arg2
);
5709 /* These are saved for the sake of maybe_warn_bool_compare. */
5710 code_orig_arg1
= TREE_CODE (TREE_TYPE (arg1
));
5711 code_orig_arg2
= TREE_CODE (TREE_TYPE (arg2
));
5714 /* =, ->, [], () must be non-static member functions. */
5716 if (code2
!= NOP_EXPR
)
5728 arg2
= prep_operand (arg2
);
5729 arg3
= prep_operand (arg3
);
5731 if (code
== COND_EXPR
)
5732 /* Use build_conditional_expr instead. */
5734 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1
))
5735 && (! arg2
|| ! OVERLOAD_TYPE_P (TREE_TYPE (arg2
))))
5738 if (code
== POSTINCREMENT_EXPR
|| code
== POSTDECREMENT_EXPR
)
5739 arg2
= integer_zero_node
;
5741 vec_alloc (arglist
, 3);
5742 arglist
->quick_push (arg1
);
5743 if (arg2
!= NULL_TREE
)
5744 arglist
->quick_push (arg2
);
5745 if (arg3
!= NULL_TREE
)
5746 arglist
->quick_push (arg3
);
5748 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5749 p
= conversion_obstack_alloc (0);
5751 /* Add namespace-scope operators to the list of functions to
5755 tree fns
= lookup_name_real (fnname
, 0, 1, /*block_p=*/true, 0, 0);
5756 fns
= lookup_arg_dependent (fnname
, fns
, arglist
);
5757 add_candidates (fns
, NULL_TREE
, arglist
, NULL_TREE
,
5758 NULL_TREE
, false, NULL_TREE
, NULL_TREE
,
5759 flags
, &candidates
, complain
);
5764 args
[2] = NULL_TREE
;
5766 /* Add class-member operators to the candidate set. */
5767 if (CLASS_TYPE_P (TREE_TYPE (arg1
)))
5771 fns
= lookup_fnfields (TREE_TYPE (arg1
), fnname
, 1);
5772 if (fns
== error_mark_node
)
5774 result
= error_mark_node
;
5775 goto user_defined_result_ready
;
5778 add_candidates (BASELINK_FUNCTIONS (fns
),
5779 NULL_TREE
, arglist
, NULL_TREE
,
5781 BASELINK_BINFO (fns
),
5782 BASELINK_ACCESS_BINFO (fns
),
5783 flags
, &candidates
, complain
);
5785 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5786 only non-member functions that have type T1 or reference to
5787 cv-qualified-opt T1 for the first argument, if the first argument
5788 has an enumeration type, or T2 or reference to cv-qualified-opt
5789 T2 for the second argument, if the second argument has an
5790 enumeration type. Filter out those that don't match. */
5791 else if (! arg2
|| ! CLASS_TYPE_P (TREE_TYPE (arg2
)))
5793 struct z_candidate
**candp
, **next
;
5795 for (candp
= &candidates
; *candp
; candp
= next
)
5797 tree parmlist
, parmtype
;
5798 int i
, nargs
= (arg2
? 2 : 1);
5803 parmlist
= TYPE_ARG_TYPES (TREE_TYPE (cand
->fn
));
5805 for (i
= 0; i
< nargs
; ++i
)
5807 parmtype
= TREE_VALUE (parmlist
);
5809 if (TYPE_REF_P (parmtype
))
5810 parmtype
= TREE_TYPE (parmtype
);
5811 if (TREE_CODE (TREE_TYPE (args
[i
])) == ENUMERAL_TYPE
5812 && (same_type_ignoring_top_level_qualifiers_p
5813 (TREE_TYPE (args
[i
]), parmtype
)))
5816 parmlist
= TREE_CHAIN (parmlist
);
5819 /* No argument has an appropriate type, so remove this
5820 candidate function from the list. */
5823 *candp
= cand
->next
;
5829 add_builtin_candidates (&candidates
, code
, code2
, fnname
, args
,
5836 /* For these, the built-in candidates set is empty
5837 [over.match.oper]/3. We don't want non-strict matches
5838 because exact matches are always possible with built-in
5839 operators. The built-in candidate set for COMPONENT_REF
5840 would be empty too, but since there are no such built-in
5841 operators, we accept non-strict matches for them. */
5850 candidates
= splice_viable (candidates
, strict_p
, &any_viable_p
);
5855 case POSTINCREMENT_EXPR
:
5856 case POSTDECREMENT_EXPR
:
5857 /* Don't try anything fancy if we're not allowed to produce
5859 if (!(complain
& tf_error
))
5860 return error_mark_node
;
5862 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5863 distinguish between prefix and postfix ++ and
5864 operator++() was used for both, so we allow this with
5868 const char *msg
= (flag_permissive
)
5869 ? G_("no %<%D(int)%> declared for postfix %qs,"
5870 " trying prefix operator instead")
5871 : G_("no %<%D(int)%> declared for postfix %qs");
5872 permerror (loc
, msg
, fnname
, OVL_OP_INFO (false, code
)->name
);
5875 if (!flag_permissive
)
5876 return error_mark_node
;
5878 if (code
== POSTINCREMENT_EXPR
)
5879 code
= PREINCREMENT_EXPR
;
5881 code
= PREDECREMENT_EXPR
;
5882 result
= build_new_op_1 (loc
, code
, flags
, arg1
, NULL_TREE
,
5883 NULL_TREE
, overload
, complain
);
5886 /* The caller will deal with these. */
5891 result_valid_p
= true;
5895 if (complain
& tf_error
)
5897 /* If one of the arguments of the operator represents
5898 an invalid use of member function pointer, try to report
5899 a meaningful error ... */
5900 if (invalid_nonstatic_memfn_p (loc
, arg1
, tf_error
)
5901 || invalid_nonstatic_memfn_p (loc
, arg2
, tf_error
)
5902 || invalid_nonstatic_memfn_p (loc
, arg3
, tf_error
))
5903 /* We displayed the error message. */;
5906 /* ... Otherwise, report the more generic
5907 "no matching operator found" error */
5908 auto_diagnostic_group d
;
5909 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, FALSE
);
5910 print_z_candidates (loc
, candidates
);
5913 result
= error_mark_node
;
5919 cand
= tourney (candidates
, complain
);
5922 if (complain
& tf_error
)
5924 auto_diagnostic_group d
;
5925 op_error (loc
, code
, code2
, arg1
, arg2
, arg3
, TRUE
);
5926 print_z_candidates (loc
, candidates
);
5928 result
= error_mark_node
;
5930 else if (TREE_CODE (cand
->fn
) == FUNCTION_DECL
)
5933 *overload
= cand
->fn
;
5935 if (resolve_args (arglist
, complain
) == NULL
)
5936 result
= error_mark_node
;
5938 result
= build_over_call (cand
, LOOKUP_NORMAL
, complain
);
5940 if (trivial_fn_p (cand
->fn
))
5941 /* There won't be a CALL_EXPR. */;
5942 else if (result
&& result
!= error_mark_node
)
5944 tree call
= extract_call_expr (result
);
5945 CALL_EXPR_OPERATOR_SYNTAX (call
) = true;
5947 if (processing_template_decl
&& DECL_HIDDEN_FRIEND_P (cand
->fn
))
5948 /* This prevents build_new_function_call from discarding this
5949 function during instantiation of the enclosing template. */
5950 KOENIG_LOOKUP_P (call
) = 1;
5952 /* Specify evaluation order as per P0145R2. */
5953 CALL_EXPR_ORDERED_ARGS (call
) = false;
5954 switch (op_is_ordered (code
))
5957 CALL_EXPR_REVERSE_ARGS (call
) = true;
5961 CALL_EXPR_ORDERED_ARGS (call
) = true;
5971 /* Give any warnings we noticed during overload resolution. */
5972 if (cand
->warnings
&& (complain
& tf_warning
))
5974 struct candidate_warning
*w
;
5975 for (w
= cand
->warnings
; w
; w
= w
->next
)
5976 joust (cand
, w
->loser
, 1, complain
);
5979 /* Check for comparison of different enum types. */
5988 if (TREE_CODE (TREE_TYPE (arg1
)) == ENUMERAL_TYPE
5989 && TREE_CODE (TREE_TYPE (arg2
)) == ENUMERAL_TYPE
5990 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1
))
5991 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2
)))
5992 && (complain
& tf_warning
))
5994 warning (OPT_Wenum_compare
,
5995 "comparison between %q#T and %q#T",
5996 TREE_TYPE (arg1
), TREE_TYPE (arg2
));
6003 /* We need to strip any leading REF_BIND so that bitfields
6004 don't cause errors. This should not remove any important
6005 conversions, because builtins don't apply to class
6006 objects directly. */
6007 conv
= cand
->convs
[0];
6008 if (conv
->kind
== ck_ref_bind
)
6009 conv
= next_conversion (conv
);
6010 arg1
= convert_like (conv
, arg1
, complain
);
6014 conv
= cand
->convs
[1];
6015 if (conv
->kind
== ck_ref_bind
)
6016 conv
= next_conversion (conv
);
6018 arg2
= decay_conversion (arg2
, complain
);
6020 /* We need to call warn_logical_operator before
6021 converting arg2 to a boolean_type, but after
6022 decaying an enumerator to its value. */
6023 if (complain
& tf_warning
)
6024 warn_logical_operator (loc
, code
, boolean_type_node
,
6025 code_orig_arg1
, arg1
,
6026 code_orig_arg2
, arg2
);
6028 arg2
= convert_like (conv
, arg2
, complain
);
6032 conv
= cand
->convs
[2];
6033 if (conv
->kind
== ck_ref_bind
)
6034 conv
= next_conversion (conv
);
6035 arg3
= convert_like (conv
, arg3
, complain
);
6041 user_defined_result_ready
:
6043 /* Free all the conversions we allocated. */
6044 obstack_free (&conversion_obstack
, p
);
6046 if (result
|| result_valid_p
)
6053 return cp_build_modify_expr (loc
, arg1
, code2
, arg2
, complain
);
6056 return cp_build_indirect_ref (arg1
, RO_UNARY_STAR
, complain
);
6058 case TRUTH_ANDIF_EXPR
:
6059 case TRUTH_ORIF_EXPR
:
6060 case TRUTH_AND_EXPR
:
6062 if (complain
& tf_warning
)
6063 warn_logical_operator (loc
, code
, boolean_type_node
,
6064 code_orig_arg1
, arg1
,
6065 code_orig_arg2
, arg2
);
6073 if ((complain
& tf_warning
)
6074 && ((code_orig_arg1
== BOOLEAN_TYPE
)
6075 ^ (code_orig_arg2
== BOOLEAN_TYPE
)))
6076 maybe_warn_bool_compare (loc
, code
, arg1
, arg2
);
6077 if (complain
& tf_warning
&& warn_tautological_compare
)
6078 warn_tautological_cmp (loc
, code
, arg1
, arg2
);
6083 case TRUNC_DIV_EXPR
:
6088 case TRUNC_MOD_EXPR
:
6092 return cp_build_binary_op (loc
, code
, arg1
, arg2
, complain
);
6094 case UNARY_PLUS_EXPR
:
6097 case TRUTH_NOT_EXPR
:
6098 case PREINCREMENT_EXPR
:
6099 case POSTINCREMENT_EXPR
:
6100 case PREDECREMENT_EXPR
:
6101 case POSTDECREMENT_EXPR
:
6105 return cp_build_unary_op (code
, arg1
, candidates
!= 0, complain
);
6108 return cp_build_array_ref (input_location
, arg1
, arg2
, complain
);
6111 return build_m_component_ref (cp_build_indirect_ref (arg1
, RO_ARROW_STAR
,
6115 /* The caller will deal with these. */
6127 /* Wrapper for above. */
6130 build_new_op (location_t loc
, enum tree_code code
, int flags
,
6131 tree arg1
, tree arg2
, tree arg3
,
6132 tree
*overload
, tsubst_flags_t complain
)
6135 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
6136 ret
= build_new_op_1 (loc
, code
, flags
, arg1
, arg2
, arg3
,
6137 overload
, complain
);
6138 timevar_cond_stop (TV_OVERLOAD
, subtime
);
6142 /* CALL was returned by some call-building function; extract the actual
6143 CALL_EXPR from any bits that have been tacked on, e.g. by
6144 convert_from_reference. */
6147 extract_call_expr (tree call
)
6149 while (TREE_CODE (call
) == COMPOUND_EXPR
)
6150 call
= TREE_OPERAND (call
, 1);
6151 if (REFERENCE_REF_P (call
))
6152 call
= TREE_OPERAND (call
, 0);
6153 if (TREE_CODE (call
) == TARGET_EXPR
)
6154 call
= TARGET_EXPR_INITIAL (call
);
6155 gcc_assert (TREE_CODE (call
) == CALL_EXPR
6156 || TREE_CODE (call
) == AGGR_INIT_EXPR
6157 || call
== error_mark_node
);
6161 /* Returns true if FN has two parameters, of which the second has type
6165 second_parm_is_size_t (tree fn
)
6167 tree t
= FUNCTION_ARG_CHAIN (fn
);
6168 if (!t
|| !same_type_p (TREE_VALUE (t
), size_type_node
))
6171 if (t
== void_list_node
)
6173 if (aligned_new_threshold
&& t
6174 && same_type_p (TREE_VALUE (t
), align_type_node
)
6175 && TREE_CHAIN (t
) == void_list_node
)
6180 /* True if T, an allocation function, has std::align_val_t as its second
6184 aligned_allocation_fn_p (tree t
)
6186 if (!aligned_new_threshold
)
6189 tree a
= FUNCTION_ARG_CHAIN (t
);
6190 return (a
&& same_type_p (TREE_VALUE (a
), align_type_node
));
6193 /* True if T is std::destroying_delete_t. */
6196 std_destroying_delete_t_p (tree t
)
6198 return (TYPE_CONTEXT (t
) == std_node
6199 && id_equal (TYPE_IDENTIFIER (t
), "destroying_delete_t"));
6202 /* A deallocation function with at least two parameters whose second parameter
6203 type is of type std::destroying_delete_t is a destroying operator delete. A
6204 destroying operator delete shall be a class member function named operator
6205 delete. [ Note: Array deletion cannot use a destroying operator
6206 delete. --end note ] */
6209 destroying_delete_p (tree t
)
6211 tree a
= TYPE_ARG_TYPES (TREE_TYPE (t
));
6212 if (!a
|| !TREE_CHAIN (a
))
6214 tree type
= TREE_VALUE (TREE_CHAIN (a
));
6215 return std_destroying_delete_t_p (type
) ? type
: NULL_TREE
;
6218 /* Returns true iff T, an element of an OVERLOAD chain, is a usual deallocation
6219 function (3.7.4.2 [basic.stc.dynamic.deallocation]) with a parameter of
6220 std::align_val_t. */
6223 aligned_deallocation_fn_p (tree t
)
6225 if (!aligned_new_threshold
)
6228 /* A template instance is never a usual deallocation function,
6229 regardless of its signature. */
6230 if (TREE_CODE (t
) == TEMPLATE_DECL
6231 || primary_template_specialization_p (t
))
6234 tree a
= FUNCTION_ARG_CHAIN (t
);
6235 if (destroying_delete_p (t
))
6237 if (same_type_p (TREE_VALUE (a
), align_type_node
)
6238 && TREE_CHAIN (a
) == void_list_node
)
6240 if (!same_type_p (TREE_VALUE (a
), size_type_node
))
6243 if (a
&& same_type_p (TREE_VALUE (a
), align_type_node
)
6244 && TREE_CHAIN (a
) == void_list_node
)
6249 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
6250 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
6253 usual_deallocation_fn_p (tree t
)
6255 /* A template instance is never a usual deallocation function,
6256 regardless of its signature. */
6257 if (TREE_CODE (t
) == TEMPLATE_DECL
6258 || primary_template_specialization_p (t
))
6261 /* If a class T has a member deallocation function named operator delete
6262 with exactly one parameter, then that function is a usual
6263 (non-placement) deallocation function. If class T does not declare
6264 such an operator delete but does declare a member deallocation
6265 function named operator delete with exactly two parameters, the second
6266 of which has type std::size_t (18.2), then this function is a usual
6267 deallocation function. */
6268 bool global
= DECL_NAMESPACE_SCOPE_P (t
);
6269 tree chain
= FUNCTION_ARG_CHAIN (t
);
6272 if (destroying_delete_p (t
))
6273 chain
= TREE_CHAIN (chain
);
6274 if (chain
== void_list_node
6275 || ((!global
|| flag_sized_deallocation
)
6276 && second_parm_is_size_t (t
)))
6278 if (aligned_deallocation_fn_p (t
))
6283 /* Build a call to operator delete. This has to be handled very specially,
6284 because the restrictions on what signatures match are different from all
6285 other call instances. For a normal delete, only a delete taking (void *)
6286 or (void *, size_t) is accepted. For a placement delete, only an exact
6287 match with the placement new is accepted.
6289 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
6290 ADDR is the pointer to be deleted.
6291 SIZE is the size of the memory block to be deleted.
6292 GLOBAL_P is true if the delete-expression should not consider
6293 class-specific delete operators.
6294 PLACEMENT is the corresponding placement new call, or NULL_TREE.
6296 If this call to "operator delete" is being generated as part to
6297 deallocate memory allocated via a new-expression (as per [expr.new]
6298 which requires that if the initialization throws an exception then
6299 we call a deallocation function), then ALLOC_FN is the allocation
6303 build_op_delete_call (enum tree_code code
, tree addr
, tree size
,
6304 bool global_p
, tree placement
,
6305 tree alloc_fn
, tsubst_flags_t complain
)
6307 tree fn
= NULL_TREE
;
6308 tree fns
, fnname
, type
, t
;
6310 if (addr
== error_mark_node
)
6311 return error_mark_node
;
6313 type
= strip_array_types (TREE_TYPE (TREE_TYPE (addr
)));
6315 fnname
= ovl_op_identifier (false, code
);
6317 if (CLASS_TYPE_P (type
)
6318 && COMPLETE_TYPE_P (complete_type (type
))
6322 If the result of the lookup is ambiguous or inaccessible, or if
6323 the lookup selects a placement deallocation function, the
6324 program is ill-formed.
6326 Therefore, we ask lookup_fnfields to complain about ambiguity. */
6328 fns
= lookup_fnfields (TYPE_BINFO (type
), fnname
, 1);
6329 if (fns
== error_mark_node
)
6330 return error_mark_node
;
6335 if (fns
== NULL_TREE
)
6336 fns
= lookup_name_nonclass (fnname
);
6338 /* Strip const and volatile from addr. */
6340 addr
= cp_convert (ptr_type_node
, addr
, complain
);
6344 /* "A declaration of a placement deallocation function matches the
6345 declaration of a placement allocation function if it has the same
6346 number of parameters and, after parameter transformations (8.3.5),
6347 all parameter types except the first are identical."
6349 So we build up the function type we want and ask instantiate_type
6350 to get it for us. */
6351 t
= FUNCTION_ARG_CHAIN (alloc_fn
);
6352 t
= tree_cons (NULL_TREE
, ptr_type_node
, t
);
6353 t
= build_function_type (void_type_node
, t
);
6355 fn
= instantiate_type (t
, fns
, tf_none
);
6356 if (fn
== error_mark_node
)
6359 fn
= MAYBE_BASELINK_FUNCTIONS (fn
);
6361 /* "If the lookup finds the two-parameter form of a usual deallocation
6362 function (3.7.4.2) and that function, considered as a placement
6363 deallocation function, would have been selected as a match for the
6364 allocation function, the program is ill-formed." */
6365 if (second_parm_is_size_t (fn
))
6367 const char *const msg1
6368 = G_("exception cleanup for this placement new selects "
6369 "non-placement operator delete");
6370 const char *const msg2
6371 = G_("%qD is a usual (non-placement) deallocation "
6372 "function in C++14 (or with -fsized-deallocation)");
6374 /* But if the class has an operator delete (void *), then that is
6375 the usual deallocation function, so we shouldn't complain
6376 about using the operator delete (void *, size_t). */
6377 if (DECL_CLASS_SCOPE_P (fn
))
6378 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
));
6382 if (usual_deallocation_fn_p (elt
)
6383 && FUNCTION_ARG_CHAIN (elt
) == void_list_node
)
6386 /* Before C++14 a two-parameter global deallocation function is
6387 always a placement deallocation function, but warn if
6389 else if (!flag_sized_deallocation
)
6391 if (complain
& tf_warning
)
6393 auto_diagnostic_group d
;
6394 if (warning (OPT_Wc__14_compat
, msg1
))
6395 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6400 if (complain
& tf_warning_or_error
)
6402 auto_diagnostic_group d
;
6403 if (permerror (input_location
, msg1
))
6405 /* Only mention C++14 for namespace-scope delete. */
6406 if (DECL_NAMESPACE_SCOPE_P (fn
))
6407 inform (DECL_SOURCE_LOCATION (fn
), msg2
, fn
);
6409 inform (DECL_SOURCE_LOCATION (fn
),
6410 "%qD is a usual (non-placement) deallocation "
6415 return error_mark_node
;
6420 /* "Any non-placement deallocation function matches a non-placement
6421 allocation function. If the lookup finds a single matching
6422 deallocation function, that function will be called; otherwise, no
6423 deallocation function will be called." */
6424 for (lkp_iterator
iter (MAYBE_BASELINK_FUNCTIONS (fns
)); iter
; ++iter
)
6427 if (usual_deallocation_fn_p (elt
))
6435 /* -- If the type has new-extended alignment, a function with a
6436 parameter of type std::align_val_t is preferred; otherwise a
6437 function without such a parameter is preferred. If exactly one
6438 preferred function is found, that function is selected and the
6439 selection process terminates. If more than one preferred
6440 function is found, all non-preferred functions are eliminated
6441 from further consideration. */
6442 if (aligned_new_threshold
)
6444 bool want_align
= type_has_new_extended_alignment (type
);
6445 bool fn_align
= aligned_deallocation_fn_p (fn
);
6446 bool elt_align
= aligned_deallocation_fn_p (elt
);
6448 if (elt_align
!= fn_align
)
6450 if (want_align
== elt_align
)
6456 /* -- If the deallocation functions have class scope, the one
6457 without a parameter of type std::size_t is selected. */
6459 if (DECL_CLASS_SCOPE_P (fn
))
6462 /* -- If the type is complete and if, for the second alternative
6463 (delete array) only, the operand is a pointer to a class type
6464 with a non-trivial destructor or a (possibly multi-dimensional)
6465 array thereof, the function with a parameter of type std::size_t
6468 -- Otherwise, it is unspecified whether a deallocation function
6469 with a parameter of type std::size_t is selected. */
6472 want_size
= COMPLETE_TYPE_P (type
);
6473 if (code
== VEC_DELETE_EXPR
6474 && !TYPE_VEC_NEW_USES_COOKIE (type
))
6475 /* We need a cookie to determine the array size. */
6478 bool fn_size
= second_parm_is_size_t (fn
);
6479 bool elt_size
= second_parm_is_size_t (elt
);
6480 gcc_assert (fn_size
!= elt_size
);
6481 if (want_size
== elt_size
)
6486 /* If we have a matching function, call it. */
6489 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
6491 /* If the FN is a member function, make sure that it is
6493 if (BASELINK_P (fns
))
6494 perform_or_defer_access_check (BASELINK_BINFO (fns
), fn
, fn
,
6497 /* Core issue 901: It's ok to new a type with deleted delete. */
6498 if (DECL_DELETED_FN (fn
) && alloc_fn
)
6503 /* The placement args might not be suitable for overload
6504 resolution at this point, so build the call directly. */
6505 int nargs
= call_expr_nargs (placement
);
6506 tree
*argarray
= XALLOCAVEC (tree
, nargs
);
6509 for (i
= 1; i
< nargs
; i
++)
6510 argarray
[i
] = CALL_EXPR_ARG (placement
, i
);
6511 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
6512 return error_mark_node
;
6513 return build_cxx_call (fn
, nargs
, argarray
, complain
);
6517 tree destroying
= destroying_delete_p (fn
);
6520 /* Strip const and volatile from addr but retain the type of the
6522 tree rtype
= TREE_TYPE (TREE_TYPE (oaddr
));
6523 rtype
= cv_unqualified (rtype
);
6524 rtype
= TYPE_POINTER_TO (rtype
);
6525 addr
= cp_convert (rtype
, oaddr
, complain
);
6526 destroying
= build_functional_cast (destroying
, NULL_TREE
,
6531 vec
<tree
, va_gc
> *args
= make_tree_vector ();
6532 args
->quick_push (addr
);
6534 args
->quick_push (destroying
);
6535 if (second_parm_is_size_t (fn
))
6536 args
->quick_push (size
);
6537 if (aligned_deallocation_fn_p (fn
))
6539 tree al
= build_int_cst (align_type_node
, TYPE_ALIGN_UNIT (type
));
6540 args
->quick_push (al
);
6542 ret
= cp_build_function_call_vec (fn
, &args
, complain
);
6543 release_tree_vector (args
);
6550 If no unambiguous matching deallocation function can be found,
6551 propagating the exception does not cause the object's memory to
6555 if ((complain
& tf_warning
)
6557 warning (0, "no corresponding deallocation function for %qD",
6562 if (complain
& tf_error
)
6563 error ("no suitable %<operator %s%> for %qT",
6564 OVL_OP_INFO (false, code
)->name
, type
);
6565 return error_mark_node
;
6568 /* Issue diagnostics about a disallowed access of DECL, using DIAG_DECL
6571 If ISSUE_ERROR is true, then issue an error about the
6572 access, followed by a note showing the declaration.
6573 Otherwise, just show the note. */
6576 complain_about_access (tree decl
, tree diag_decl
, bool issue_error
)
6578 if (TREE_PRIVATE (decl
))
6581 error ("%q#D is private within this context", diag_decl
);
6582 inform (DECL_SOURCE_LOCATION (diag_decl
),
6583 "declared private here");
6585 else if (TREE_PROTECTED (decl
))
6588 error ("%q#D is protected within this context", diag_decl
);
6589 inform (DECL_SOURCE_LOCATION (diag_decl
),
6590 "declared protected here");
6595 error ("%q#D is inaccessible within this context", diag_decl
);
6596 inform (DECL_SOURCE_LOCATION (diag_decl
), "declared here");
6600 /* If the current scope isn't allowed to access DECL along
6601 BASETYPE_PATH, give an error. The most derived class in
6602 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6603 the declaration to use in the error diagnostic. */
6606 enforce_access (tree basetype_path
, tree decl
, tree diag_decl
,
6607 tsubst_flags_t complain
, access_failure_info
*afi
)
6609 gcc_assert (TREE_CODE (basetype_path
) == TREE_BINFO
);
6611 if (flag_new_inheriting_ctors
6612 && DECL_INHERITED_CTOR (decl
))
6614 /* 7.3.3/18: The additional constructors are accessible if they would be
6615 accessible when used to construct an object of the corresponding base
6617 decl
= strip_inheriting_ctors (decl
);
6618 basetype_path
= lookup_base (basetype_path
, DECL_CONTEXT (decl
),
6619 ba_any
, NULL
, complain
);
6622 if (!accessible_p (basetype_path
, decl
, true))
6624 if (flag_new_inheriting_ctors
)
6625 diag_decl
= strip_inheriting_ctors (diag_decl
);
6626 if (complain
& tf_error
)
6627 complain_about_access (decl
, diag_decl
, true);
6629 afi
->record_access_failure (basetype_path
, decl
, diag_decl
);
6636 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6637 bitwise or of LOOKUP_* values. If any errors are warnings are
6638 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6639 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6643 build_temp (tree expr
, tree type
, int flags
,
6644 diagnostic_t
*diagnostic_kind
, tsubst_flags_t complain
)
6647 vec
<tree
, va_gc
> *args
;
6649 *diagnostic_kind
= DK_UNSPECIFIED
;
6651 /* If the source is a packed field, calling the copy constructor will require
6652 binding the field to the reference parameter to the copy constructor, and
6653 we'll end up with an infinite loop. If we can use a bitwise copy, then
6655 if ((lvalue_kind (expr
) & clk_packed
)
6656 && CLASS_TYPE_P (TREE_TYPE (expr
))
6657 && !type_has_nontrivial_copy_init (TREE_TYPE (expr
)))
6658 return get_target_expr_sfinae (expr
, complain
);
6660 savew
= warningcount
+ werrorcount
, savee
= errorcount
;
6661 args
= make_tree_vector_single (expr
);
6662 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
6663 &args
, type
, flags
, complain
);
6664 release_tree_vector (args
);
6665 if (warningcount
+ werrorcount
> savew
)
6666 *diagnostic_kind
= DK_WARNING
;
6667 else if (errorcount
> savee
)
6668 *diagnostic_kind
= DK_ERROR
;
6672 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6673 Also handle a subset of zero as null warnings.
6674 EXPR is implicitly converted to type TOTYPE.
6675 FN and ARGNUM are used for diagnostics. */
6678 conversion_null_warnings (tree totype
, tree expr
, tree fn
, int argnum
)
6680 /* Issue warnings about peculiar, but valid, uses of NULL. */
6681 if (null_node_p (expr
) && TREE_CODE (totype
) != BOOLEAN_TYPE
6682 && ARITHMETIC_TYPE_P (totype
))
6684 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6685 loc
= expansion_point_location_if_in_system_header (loc
);
6688 auto_diagnostic_group d
;
6689 if (warning_at (loc
, OPT_Wconversion_null
,
6690 "passing NULL to non-pointer argument %P of %qD",
6692 inform (get_fndecl_argument_location (fn
, argnum
),
6696 warning_at (loc
, OPT_Wconversion_null
,
6697 "converting to non-pointer type %qT from NULL", totype
);
6700 /* Issue warnings if "false" is converted to a NULL pointer */
6701 else if (TREE_CODE (TREE_TYPE (expr
)) == BOOLEAN_TYPE
6702 && TYPE_PTR_P (totype
))
6704 location_t loc
= EXPR_LOC_OR_LOC (expr
, input_location
);
6707 auto_diagnostic_group d
;
6708 if (warning_at (loc
, OPT_Wconversion_null
,
6709 "converting %<false%> to pointer type for argument "
6710 "%P of %qD", argnum
, fn
))
6711 inform (get_fndecl_argument_location (fn
, argnum
),
6715 warning_at (loc
, OPT_Wconversion_null
,
6716 "converting %<false%> to pointer type %qT", totype
);
6718 /* Handle zero as null pointer warnings for cases other
6719 than EQ_EXPR and NE_EXPR */
6720 else if (null_ptr_cst_p (expr
) &&
6721 (TYPE_PTR_OR_PTRMEM_P (totype
) || NULLPTR_TYPE_P (totype
)))
6724 expansion_point_location_if_in_system_header (input_location
);
6725 maybe_warn_zero_as_null_pointer_constant (expr
, loc
);
6729 /* We gave a diagnostic during a conversion. If this was in the second
6730 standard conversion sequence of a user-defined conversion sequence, say
6731 which user-defined conversion. */
6734 maybe_print_user_conv_context (conversion
*convs
)
6736 if (convs
->user_conv_p
)
6737 for (conversion
*t
= convs
; t
; t
= next_conversion (t
))
6738 if (t
->kind
== ck_user
)
6740 print_z_candidate (0, " after user-defined conversion:",
6746 /* Locate the parameter with the given index within FNDECL.
6747 ARGNUM is zero based, -1 indicates the `this' argument of a method.
6748 Return the location of the FNDECL itself if there are problems. */
6751 get_fndecl_argument_location (tree fndecl
, int argnum
)
6753 /* The locations of implicitly-declared functions are likely to be
6754 more meaningful than those of their parameters. */
6755 if (DECL_ARTIFICIAL (fndecl
))
6756 return DECL_SOURCE_LOCATION (fndecl
);
6761 /* Locate param by index within DECL_ARGUMENTS (fndecl). */
6762 for (i
= 0, param
= FUNCTION_FIRST_USER_PARM (fndecl
);
6763 i
< argnum
&& param
;
6764 i
++, param
= TREE_CHAIN (param
))
6767 /* If something went wrong (e.g. if we have a builtin and thus no arguments),
6768 return the location of FNDECL. */
6770 return DECL_SOURCE_LOCATION (fndecl
);
6772 return DECL_SOURCE_LOCATION (param
);
6775 /* If FNDECL is non-NULL, issue a note highlighting ARGNUM
6776 within its declaration (or the fndecl itself if something went
6780 maybe_inform_about_fndecl_for_bogus_argument_init (tree fn
, int argnum
)
6783 inform (get_fndecl_argument_location (fn
, argnum
),
6784 " initializing argument %P of %qD", argnum
, fn
);
6787 /* Perform the conversions in CONVS on the expression EXPR. FN and
6788 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6789 indicates the `this' argument of a method. INNER is nonzero when
6790 being called to continue a conversion chain. It is negative when a
6791 reference binding will be applied, positive otherwise. If
6792 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6793 conversions will be emitted if appropriate. If C_CAST_P is true,
6794 this conversion is coming from a C-style cast; in that case,
6795 conversions to inaccessible bases are permitted. */
6798 convert_like_real (conversion
*convs
, tree expr
, tree fn
, int argnum
,
6799 bool issue_conversion_warnings
,
6800 bool c_cast_p
, tsubst_flags_t complain
)
6802 tree totype
= convs
->type
;
6803 diagnostic_t diag_kind
;
6805 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
6807 if (convs
->bad_p
&& !(complain
& tf_error
))
6808 return error_mark_node
;
6811 && convs
->kind
!= ck_user
6812 && convs
->kind
!= ck_list
6813 && convs
->kind
!= ck_ambig
6814 && (convs
->kind
!= ck_ref_bind
6815 || (convs
->user_conv_p
&& next_conversion (convs
)->bad_p
))
6816 && (convs
->kind
!= ck_rvalue
6817 || SCALAR_TYPE_P (totype
))
6818 && convs
->kind
!= ck_base
)
6820 bool complained
= false;
6821 conversion
*t
= convs
;
6823 /* Give a helpful error if this is bad because of excess braces. */
6824 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6825 && SCALAR_TYPE_P (totype
)
6826 && CONSTRUCTOR_NELTS (expr
) > 0
6827 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr
, 0)->value
))
6829 complained
= permerror (loc
, "too many braces around initializer "
6831 while (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6832 && CONSTRUCTOR_NELTS (expr
) == 1)
6833 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6836 /* Give a helpful error if this is bad because a conversion to bool
6837 from std::nullptr_t requires direct-initialization. */
6838 if (NULLPTR_TYPE_P (TREE_TYPE (expr
))
6839 && TREE_CODE (totype
) == BOOLEAN_TYPE
)
6840 complained
= permerror (loc
, "converting to %qH from %qI requires "
6841 "direct-initialization",
6842 totype
, TREE_TYPE (expr
));
6844 for (; t
; t
= next_conversion (t
))
6846 if (t
->kind
== ck_user
&& t
->cand
->reason
)
6848 auto_diagnostic_group d
;
6849 complained
= permerror (loc
, "invalid user-defined conversion "
6850 "from %qH to %qI", TREE_TYPE (expr
),
6853 print_z_candidate (loc
, "candidate is:", t
->cand
);
6854 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6855 /*issue_conversion_warnings=*/false,
6858 if (convs
->kind
== ck_ref_bind
)
6859 expr
= convert_to_reference (totype
, expr
, CONV_IMPLICIT
,
6860 LOOKUP_NORMAL
, NULL_TREE
,
6863 expr
= cp_convert (totype
, expr
, complain
);
6865 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
6868 else if (t
->kind
== ck_user
|| !t
->bad_p
)
6870 expr
= convert_like_real (t
, expr
, fn
, argnum
,
6871 /*issue_conversion_warnings=*/false,
6876 else if (t
->kind
== ck_ambig
)
6877 return convert_like_real (t
, expr
, fn
, argnum
,
6878 /*issue_conversion_warnings=*/false,
6881 else if (t
->kind
== ck_identity
)
6886 range_label_for_type_mismatch
label (TREE_TYPE (expr
), totype
);
6887 gcc_rich_location
richloc (loc
, &label
);
6888 complained
= permerror (&richloc
,
6889 "invalid conversion from %qH to %qI",
6890 TREE_TYPE (expr
), totype
);
6893 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
6895 return cp_convert (totype
, expr
, complain
);
6898 if (issue_conversion_warnings
&& (complain
& tf_warning
))
6899 conversion_null_warnings (totype
, expr
, fn
, argnum
);
6901 switch (convs
->kind
)
6905 struct z_candidate
*cand
= convs
->cand
;
6908 /* We chose the surrogate function from add_conv_candidate, now we
6909 actually need to build the conversion. */
6910 cand
= build_user_type_conversion_1 (totype
, expr
,
6911 LOOKUP_NO_CONVERSION
, complain
);
6913 tree convfn
= cand
->fn
;
6915 /* When converting from an init list we consider explicit
6916 constructors, but actually trying to call one is an error. */
6917 if (DECL_NONCONVERTING_P (convfn
) && DECL_CONSTRUCTOR_P (convfn
)
6918 && BRACE_ENCLOSED_INITIALIZER_P (expr
)
6919 /* Unless this is for direct-list-initialization. */
6920 && !CONSTRUCTOR_IS_DIRECT_INIT (expr
)
6921 /* And in C++98 a default constructor can't be explicit. */
6922 && cxx_dialect
>= cxx11
)
6924 if (!(complain
& tf_error
))
6925 return error_mark_node
;
6926 location_t loc
= location_of (expr
);
6927 if (CONSTRUCTOR_NELTS (expr
) == 0
6928 && FUNCTION_FIRST_USER_PARMTYPE (convfn
) != void_list_node
)
6930 auto_diagnostic_group d
;
6931 if (pedwarn (loc
, 0, "converting to %qT from initializer list "
6932 "would use explicit constructor %qD",
6934 inform (loc
, "in C++11 and above a default constructor "
6938 error ("converting to %qT from initializer list would use "
6939 "explicit constructor %qD", totype
, convfn
);
6942 /* If we're initializing from {}, it's value-initialization. */
6943 if (BRACE_ENCLOSED_INITIALIZER_P (expr
)
6944 && CONSTRUCTOR_NELTS (expr
) == 0
6945 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype
))
6947 bool direct
= CONSTRUCTOR_IS_DIRECT_INIT (expr
);
6948 if (abstract_virtuals_error_sfinae (NULL_TREE
, totype
, complain
))
6949 return error_mark_node
;
6950 expr
= build_value_init (totype
, complain
);
6951 expr
= get_target_expr_sfinae (expr
, complain
);
6952 if (expr
!= error_mark_node
)
6954 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6955 TARGET_EXPR_DIRECT_INIT_P (expr
) = direct
;
6960 expr
= mark_rvalue_use (expr
);
6962 /* Pass LOOKUP_NO_CONVERSION so rvalue/base handling knows not to allow
6964 expr
= build_over_call (cand
, LOOKUP_NORMAL
|LOOKUP_NO_CONVERSION
,
6967 /* If this is a constructor or a function returning an aggr type,
6968 we need to build up a TARGET_EXPR. */
6969 if (DECL_CONSTRUCTOR_P (convfn
))
6971 expr
= build_cplus_new (totype
, expr
, complain
);
6973 /* Remember that this was list-initialization. */
6974 if (convs
->check_narrowing
&& expr
!= error_mark_node
)
6975 TARGET_EXPR_LIST_INIT_P (expr
) = true;
6981 if (BRACE_ENCLOSED_INITIALIZER_P (expr
))
6983 int nelts
= CONSTRUCTOR_NELTS (expr
);
6985 expr
= build_value_init (totype
, complain
);
6986 else if (nelts
== 1)
6987 expr
= CONSTRUCTOR_ELT (expr
, 0)->value
;
6991 expr
= mark_use (expr
, /*rvalue_p=*/!convs
->rvaluedness_matches_p
,
6992 /*read_p=*/true, UNKNOWN_LOCATION
,
6993 /*reject_builtin=*/true);
6995 if (type_unknown_p (expr
))
6996 expr
= instantiate_type (totype
, expr
, complain
);
6997 if (expr
== null_node
6998 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype
))
6999 /* If __null has been converted to an integer type, we do not want to
7000 continue to warn about uses of EXPR as an integer, rather than as a
7002 expr
= build_int_cst (totype
, 0);
7005 /* We leave bad_p off ck_ambig because overload resolution considers
7006 it valid, it just fails when we try to perform it. So we need to
7007 check complain here, too. */
7008 if (complain
& tf_error
)
7010 /* Call build_user_type_conversion again for the error. */
7011 int flags
= (convs
->need_temporary_p
7012 ? LOOKUP_IMPLICIT
: LOOKUP_NORMAL
);
7013 build_user_type_conversion (totype
, convs
->u
.expr
, flags
, complain
);
7014 gcc_assert (seen_error ());
7015 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7017 return error_mark_node
;
7021 /* Conversion to std::initializer_list<T>. */
7022 tree elttype
= TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype
), 0);
7023 tree new_ctor
= build_constructor (init_list_type_node
, NULL
);
7024 unsigned len
= CONSTRUCTOR_NELTS (expr
);
7025 tree array
, val
, field
;
7026 vec
<constructor_elt
, va_gc
> *vec
= NULL
;
7029 /* Convert all the elements. */
7030 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr
), ix
, val
)
7032 tree sub
= convert_like_real (convs
->u
.list
[ix
], val
, fn
, argnum
,
7033 false, false, complain
);
7034 if (sub
== error_mark_node
)
7036 if (!BRACE_ENCLOSED_INITIALIZER_P (val
)
7037 && !check_narrowing (TREE_TYPE (sub
), val
, complain
))
7038 return error_mark_node
;
7039 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor
), NULL_TREE
, sub
);
7040 if (!TREE_CONSTANT (sub
))
7041 TREE_CONSTANT (new_ctor
) = false;
7043 /* Build up the array. */
7044 elttype
= cp_build_qualified_type
7045 (elttype
, cp_type_quals (elttype
) | TYPE_QUAL_CONST
);
7046 array
= build_array_of_n_type (elttype
, len
);
7047 array
= finish_compound_literal (array
, new_ctor
, complain
);
7048 /* Take the address explicitly rather than via decay_conversion
7049 to avoid the error about taking the address of a temporary. */
7050 array
= cp_build_addr_expr (array
, complain
);
7051 array
= cp_convert (build_pointer_type (elttype
), array
, complain
);
7052 if (array
== error_mark_node
)
7053 return error_mark_node
;
7055 /* Build up the initializer_list object. Note: fail gracefully
7056 if the object cannot be completed because, for example, no
7057 definition is provided (c++/80956). */
7058 totype
= complete_type_or_maybe_complain (totype
, NULL_TREE
, complain
);
7060 return error_mark_node
;
7061 field
= next_initializable_field (TYPE_FIELDS (totype
));
7062 CONSTRUCTOR_APPEND_ELT (vec
, field
, array
);
7063 field
= next_initializable_field (DECL_CHAIN (field
));
7064 CONSTRUCTOR_APPEND_ELT (vec
, field
, size_int (len
));
7065 new_ctor
= build_constructor (totype
, vec
);
7066 return get_target_expr_sfinae (new_ctor
, complain
);
7070 if (TREE_CODE (totype
) == COMPLEX_TYPE
)
7072 tree real
= CONSTRUCTOR_ELT (expr
, 0)->value
;
7073 tree imag
= CONSTRUCTOR_ELT (expr
, 1)->value
;
7074 real
= perform_implicit_conversion (TREE_TYPE (totype
),
7076 imag
= perform_implicit_conversion (TREE_TYPE (totype
),
7078 expr
= build2 (COMPLEX_EXPR
, totype
, real
, imag
);
7081 expr
= reshape_init (totype
, expr
, complain
);
7082 expr
= get_target_expr_sfinae (digest_init (totype
, expr
, complain
),
7084 if (expr
!= error_mark_node
)
7085 TARGET_EXPR_LIST_INIT_P (expr
) = true;
7092 expr
= convert_like_real (next_conversion (convs
), expr
, fn
, argnum
,
7093 convs
->kind
== ck_ref_bind
7094 ? issue_conversion_warnings
: false,
7095 c_cast_p
, complain
);
7096 if (expr
== error_mark_node
)
7097 return error_mark_node
;
7099 switch (convs
->kind
)
7102 expr
= decay_conversion (expr
, complain
);
7103 if (expr
== error_mark_node
)
7105 if (complain
& tf_error
)
7107 auto_diagnostic_group d
;
7108 maybe_print_user_conv_context (convs
);
7109 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7111 return error_mark_node
;
7114 if (! MAYBE_CLASS_TYPE_P (totype
))
7117 /* Don't introduce copies when passing arguments along to the inherited
7119 if (current_function_decl
7120 && flag_new_inheriting_ctors
7121 && DECL_INHERITED_CTOR (current_function_decl
))
7124 if (TREE_CODE (expr
) == TARGET_EXPR
7125 && TARGET_EXPR_LIST_INIT_P (expr
))
7126 /* Copy-list-initialization doesn't actually involve a copy. */
7131 if (convs
->kind
== ck_base
&& !convs
->need_temporary_p
)
7133 /* We are going to bind a reference directly to a base-class
7134 subobject of EXPR. */
7135 /* Build an expression for `*((base*) &expr)'. */
7136 expr
= convert_to_base (expr
, totype
,
7137 !c_cast_p
, /*nonnull=*/true, complain
);
7141 /* Copy-initialization where the cv-unqualified version of the source
7142 type is the same class as, or a derived class of, the class of the
7143 destination [is treated as direct-initialization]. [dcl.init] */
7144 flags
= LOOKUP_NORMAL
;
7145 if (convs
->user_conv_p
)
7146 /* This conversion is being done in the context of a user-defined
7147 conversion (i.e. the second step of copy-initialization), so
7148 don't allow any more. */
7149 flags
|= LOOKUP_NO_CONVERSION
;
7151 flags
|= LOOKUP_ONLYCONVERTING
;
7152 if (convs
->rvaluedness_matches_p
)
7153 /* standard_conversion got LOOKUP_PREFER_RVALUE. */
7154 flags
|= LOOKUP_PREFER_RVALUE
;
7155 expr
= build_temp (expr
, totype
, flags
, &diag_kind
, complain
);
7156 if (diag_kind
&& complain
)
7158 auto_diagnostic_group d
;
7159 maybe_print_user_conv_context (convs
);
7160 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7163 return build_cplus_new (totype
, expr
, complain
);
7167 tree ref_type
= totype
;
7169 if (convs
->bad_p
&& !next_conversion (convs
)->bad_p
)
7171 tree extype
= TREE_TYPE (expr
);
7172 auto_diagnostic_group d
;
7173 if (TYPE_REF_IS_RVALUE (ref_type
)
7175 error_at (loc
, "cannot bind rvalue reference of type %qH to "
7176 "lvalue of type %qI", totype
, extype
);
7177 else if (!TYPE_REF_IS_RVALUE (ref_type
) && !lvalue_p (expr
)
7178 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type
)))
7179 error_at (loc
, "cannot bind non-const lvalue reference of "
7180 "type %qH to an rvalue of type %qI", totype
, extype
);
7181 else if (!reference_compatible_p (TREE_TYPE (totype
), extype
))
7182 error_at (loc
, "binding reference of type %qH to %qI "
7183 "discards qualifiers", totype
, extype
);
7186 maybe_print_user_conv_context (convs
);
7187 maybe_inform_about_fndecl_for_bogus_argument_init (fn
, argnum
);
7189 return error_mark_node
;
7192 /* If necessary, create a temporary.
7194 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
7195 that need temporaries, even when their types are reference
7196 compatible with the type of reference being bound, so the
7197 upcoming call to cp_build_addr_expr doesn't fail. */
7198 if (convs
->need_temporary_p
7199 || TREE_CODE (expr
) == CONSTRUCTOR
7200 || TREE_CODE (expr
) == VA_ARG_EXPR
)
7202 /* Otherwise, a temporary of type "cv1 T1" is created and
7203 initialized from the initializer expression using the rules
7204 for a non-reference copy-initialization (8.5). */
7206 tree type
= TREE_TYPE (ref_type
);
7207 cp_lvalue_kind lvalue
= lvalue_kind (expr
);
7209 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7210 (type
, next_conversion (convs
)->type
));
7211 if (!CP_TYPE_CONST_NON_VOLATILE_P (type
)
7212 && !TYPE_REF_IS_RVALUE (ref_type
))
7214 /* If the reference is volatile or non-const, we
7215 cannot create a temporary. */
7216 if (lvalue
& clk_bitfield
)
7217 error_at (loc
, "cannot bind bitfield %qE to %qT",
7219 else if (lvalue
& clk_packed
)
7220 error_at (loc
, "cannot bind packed field %qE to %qT",
7223 error_at (loc
, "cannot bind rvalue %qE to %qT",
7225 return error_mark_node
;
7227 /* If the source is a packed field, and we must use a copy
7228 constructor, then building the target expr will require
7229 binding the field to the reference parameter to the
7230 copy constructor, and we'll end up with an infinite
7231 loop. If we can use a bitwise copy, then we'll be
7233 if ((lvalue
& clk_packed
)
7234 && CLASS_TYPE_P (type
)
7235 && type_has_nontrivial_copy_init (type
))
7237 error_at (loc
, "cannot bind packed field %qE to %qT",
7239 return error_mark_node
;
7241 if (lvalue
& clk_bitfield
)
7243 expr
= convert_bitfield_to_declared_type (expr
);
7244 expr
= fold_convert (type
, expr
);
7246 expr
= build_target_expr_with_type (expr
, type
, complain
);
7249 /* Take the address of the thing to which we will bind the
7251 expr
= cp_build_addr_expr (expr
, complain
);
7252 if (expr
== error_mark_node
)
7253 return error_mark_node
;
7255 /* Convert it to a pointer to the type referred to by the
7256 reference. This will adjust the pointer if a derived to
7257 base conversion is being performed. */
7258 expr
= cp_convert (build_pointer_type (TREE_TYPE (ref_type
)),
7260 /* Convert the pointer to the desired reference type. */
7261 return build_nop (ref_type
, expr
);
7265 return decay_conversion (expr
, complain
);
7268 /* ??? Should the address of a transaction-safe pointer point to the TM
7269 clone, and this conversion look up the primary function? */
7270 return build_nop (totype
, expr
);
7273 /* Warn about deprecated conversion if appropriate. */
7274 string_conv_p (totype
, expr
, 1);
7279 expr
= convert_to_base (expr
, totype
, !c_cast_p
,
7280 /*nonnull=*/false, complain
);
7281 return build_nop (totype
, expr
);
7284 return convert_ptrmem (totype
, expr
, /*allow_inverse_p=*/false,
7285 c_cast_p
, complain
);
7291 if (convs
->check_narrowing
7292 && !check_narrowing (totype
, expr
, complain
,
7293 convs
->check_narrowing_const_only
))
7294 return error_mark_node
;
7296 warning_sentinel
w (warn_zero_as_null_pointer_constant
);
7297 if (issue_conversion_warnings
)
7298 expr
= cp_convert_and_check (totype
, expr
, complain
);
7300 expr
= cp_convert (totype
, expr
, complain
);
7305 /* ARG is being passed to a varargs function. Perform any conversions
7306 required. Return the converted value. */
7309 convert_arg_to_ellipsis (tree arg
, tsubst_flags_t complain
)
7312 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
7316 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
7317 standard conversions are performed. */
7318 arg
= decay_conversion (arg
, complain
);
7319 arg_type
= TREE_TYPE (arg
);
7322 If the argument has integral or enumeration type that is subject
7323 to the integral promotions (_conv.prom_), or a floating point
7324 type that is subject to the floating point promotion
7325 (_conv.fpprom_), the value of the argument is converted to the
7326 promoted type before the call. */
7327 if (TREE_CODE (arg_type
) == REAL_TYPE
7328 && (TYPE_PRECISION (arg_type
)
7329 < TYPE_PRECISION (double_type_node
))
7330 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type
)))
7332 if ((complain
& tf_warning
)
7333 && warn_double_promotion
&& !c_inhibit_evaluation_warnings
)
7334 warning_at (loc
, OPT_Wdouble_promotion
,
7335 "implicit conversion from %qH to %qI when passing "
7336 "argument to function",
7337 arg_type
, double_type_node
);
7338 arg
= convert_to_real_nofold (double_type_node
, arg
);
7340 else if (NULLPTR_TYPE_P (arg_type
))
7341 arg
= null_pointer_node
;
7342 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type
))
7344 if (SCOPED_ENUM_P (arg_type
))
7346 tree prom
= cp_convert (ENUM_UNDERLYING_TYPE (arg_type
), arg
,
7348 prom
= cp_perform_integral_promotions (prom
, complain
);
7349 if (abi_version_crosses (6)
7350 && TYPE_MODE (TREE_TYPE (prom
)) != TYPE_MODE (arg_type
)
7351 && (complain
& tf_warning
))
7352 warning_at (loc
, OPT_Wabi
, "scoped enum %qT passed through ... as "
7353 "%qT before -fabi-version=6, %qT after", arg_type
,
7354 TREE_TYPE (prom
), ENUM_UNDERLYING_TYPE (arg_type
));
7355 if (!abi_version_at_least (6))
7359 arg
= cp_perform_integral_promotions (arg
, complain
);
7362 arg
= require_complete_type_sfinae (arg
, complain
);
7363 arg_type
= TREE_TYPE (arg
);
7365 if (arg
!= error_mark_node
7366 /* In a template (or ill-formed code), we can have an incomplete type
7367 even after require_complete_type_sfinae, in which case we don't know
7368 whether it has trivial copy or not. */
7369 && COMPLETE_TYPE_P (arg_type
)
7370 && !cp_unevaluated_operand
)
7372 /* [expr.call] 5.2.2/7:
7373 Passing a potentially-evaluated argument of class type (Clause 9)
7374 with a non-trivial copy constructor or a non-trivial destructor
7375 with no corresponding parameter is conditionally-supported, with
7376 implementation-defined semantics.
7378 We support it as pass-by-invisible-reference, just like a normal
7381 If the call appears in the context of a sizeof expression,
7382 it is not potentially-evaluated. */
7383 if (type_has_nontrivial_copy_init (arg_type
)
7384 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type
))
7386 arg
= force_rvalue (arg
, complain
);
7387 if (complain
& tf_warning
)
7388 warning (OPT_Wconditionally_supported
,
7389 "passing objects of non-trivially-copyable "
7390 "type %q#T through %<...%> is conditionally supported",
7392 return build1 (ADDR_EXPR
, build_reference_type (arg_type
), arg
);
7394 /* Build up a real lvalue-to-rvalue conversion in case the
7395 copy constructor is trivial but not callable. */
7396 else if (CLASS_TYPE_P (arg_type
))
7397 force_rvalue (arg
, complain
);
7404 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
7407 build_x_va_arg (location_t loc
, tree expr
, tree type
)
7409 if (processing_template_decl
)
7411 tree r
= build_min (VA_ARG_EXPR
, type
, expr
);
7412 SET_EXPR_LOCATION (r
, loc
);
7416 type
= complete_type_or_else (type
, NULL_TREE
);
7418 if (expr
== error_mark_node
|| !type
)
7419 return error_mark_node
;
7421 expr
= mark_lvalue_use (expr
);
7423 if (TYPE_REF_P (type
))
7425 error ("cannot receive reference type %qT through %<...%>", type
);
7426 return error_mark_node
;
7429 if (type_has_nontrivial_copy_init (type
)
7430 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
7432 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
7433 it as pass by invisible reference. */
7434 warning_at (loc
, OPT_Wconditionally_supported
,
7435 "receiving objects of non-trivially-copyable type %q#T "
7436 "through %<...%> is conditionally-supported", type
);
7438 tree ref
= cp_build_reference_type (type
, false);
7439 expr
= build_va_arg (loc
, expr
, ref
);
7440 return convert_from_reference (expr
);
7443 tree ret
= build_va_arg (loc
, expr
, type
);
7444 if (CLASS_TYPE_P (type
))
7445 /* Wrap the VA_ARG_EXPR in a TARGET_EXPR now so other code doesn't need to
7446 know how to handle it. */
7447 ret
= get_target_expr (ret
);
7451 /* TYPE has been given to va_arg. Apply the default conversions which
7452 would have happened when passed via ellipsis. Return the promoted
7453 type, or the passed type if there is no change. */
7456 cxx_type_promotes_to (tree type
)
7460 /* Perform the array-to-pointer and function-to-pointer
7462 type
= type_decays_to (type
);
7464 promote
= type_promotes_to (type
);
7465 if (same_type_p (type
, promote
))
7471 /* ARG is a default argument expression being passed to a parameter of
7472 the indicated TYPE, which is a parameter to FN. PARMNUM is the
7473 zero-based argument number. Do any required conversions. Return
7474 the converted value. */
7476 static GTY(()) vec
<tree
, va_gc
> *default_arg_context
;
7478 push_defarg_context (tree fn
)
7479 { vec_safe_push (default_arg_context
, fn
); }
7482 pop_defarg_context (void)
7483 { default_arg_context
->pop (); }
7486 convert_default_arg (tree type
, tree arg
, tree fn
, int parmnum
,
7487 tsubst_flags_t complain
)
7492 /* See through clones. */
7493 fn
= DECL_ORIGIN (fn
);
7494 /* And inheriting ctors. */
7495 if (flag_new_inheriting_ctors
)
7496 fn
= strip_inheriting_ctors (fn
);
7498 /* Detect recursion. */
7499 FOR_EACH_VEC_SAFE_ELT (default_arg_context
, i
, t
)
7502 if (complain
& tf_error
)
7503 error ("recursive evaluation of default argument for %q#D", fn
);
7504 return error_mark_node
;
7507 /* If the ARG is an unparsed default argument expression, the
7508 conversion cannot be performed. */
7509 if (TREE_CODE (arg
) == DEFAULT_ARG
)
7511 if (complain
& tf_error
)
7512 error ("call to %qD uses the default argument for parameter %P, which "
7513 "is not yet defined", fn
, parmnum
);
7514 return error_mark_node
;
7517 push_defarg_context (fn
);
7519 if (fn
&& DECL_TEMPLATE_INFO (fn
))
7520 arg
= tsubst_default_argument (fn
, parmnum
, type
, arg
, complain
);
7526 The names in the expression are bound, and the semantic
7527 constraints are checked, at the point where the default
7528 expressions appears.
7530 we must not perform access checks here. */
7531 push_deferring_access_checks (dk_no_check
);
7532 /* We must make a copy of ARG, in case subsequent processing
7533 alters any part of it. */
7534 arg
= break_out_target_exprs (arg
, /*clear location*/true);
7536 arg
= convert_for_initialization (0, type
, arg
, LOOKUP_IMPLICIT
,
7537 ICR_DEFAULT_ARGUMENT
, fn
, parmnum
,
7539 arg
= convert_for_arg_passing (type
, arg
, complain
);
7540 pop_deferring_access_checks();
7542 pop_defarg_context ();
7547 /* Returns the type which will really be used for passing an argument of
7551 type_passed_as (tree type
)
7553 /* Pass classes with copy ctors by invisible reference. */
7554 if (TREE_ADDRESSABLE (type
))
7556 type
= build_reference_type (type
);
7557 /* There are no other pointers to this temporary. */
7558 type
= cp_build_qualified_type (type
, TYPE_QUAL_RESTRICT
);
7560 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7561 && INTEGRAL_TYPE_P (type
)
7562 && COMPLETE_TYPE_P (type
)
7563 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7564 type
= integer_type_node
;
7569 /* Actually perform the appropriate conversion. */
7572 convert_for_arg_passing (tree type
, tree val
, tsubst_flags_t complain
)
7576 /* If VAL is a bitfield, then -- since it has already been converted
7577 to TYPE -- it cannot have a precision greater than TYPE.
7579 If it has a smaller precision, we must widen it here. For
7580 example, passing "int f:3;" to a function expecting an "int" will
7581 not result in any conversion before this point.
7583 If the precision is the same we must not risk widening. For
7584 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
7585 often have type "int", even though the C++ type for the field is
7586 "long long". If the value is being passed to a function
7587 expecting an "int", then no conversions will be required. But,
7588 if we call convert_bitfield_to_declared_type, the bitfield will
7589 be converted to "long long". */
7590 bitfield_type
= is_bitfield_expr_with_lowered_type (val
);
7592 && TYPE_PRECISION (TREE_TYPE (val
)) < TYPE_PRECISION (type
))
7593 val
= convert_to_integer_nofold (TYPE_MAIN_VARIANT (bitfield_type
), val
);
7595 if (val
== error_mark_node
)
7597 /* Pass classes with copy ctors by invisible reference. */
7598 else if (TREE_ADDRESSABLE (type
))
7599 val
= build1 (ADDR_EXPR
, build_reference_type (type
), val
);
7600 else if (targetm
.calls
.promote_prototypes (NULL_TREE
)
7601 && INTEGRAL_TYPE_P (type
)
7602 && COMPLETE_TYPE_P (type
)
7603 && tree_int_cst_lt (TYPE_SIZE (type
), TYPE_SIZE (integer_type_node
)))
7604 val
= cp_perform_integral_promotions (val
, complain
);
7605 if (complain
& tf_warning
)
7607 if (warn_suggest_attribute_format
)
7609 tree rhstype
= TREE_TYPE (val
);
7610 const enum tree_code coder
= TREE_CODE (rhstype
);
7611 const enum tree_code codel
= TREE_CODE (type
);
7612 if ((codel
== POINTER_TYPE
|| codel
== REFERENCE_TYPE
)
7614 && check_missing_format_attribute (type
, rhstype
))
7615 warning (OPT_Wsuggest_attribute_format
,
7616 "argument of function call might be a candidate "
7617 "for a format attribute");
7619 maybe_warn_parm_abi (type
, cp_expr_loc_or_loc (val
, input_location
));
7624 /* Returns non-zero iff FN is a function with magic varargs, i.e. ones for
7625 which just decay_conversion or no conversions at all should be done.
7626 This is true for some builtins which don't act like normal functions.
7627 Return 2 if no conversions at all should be done, 1 if just
7628 decay_conversion. Return 3 for special treatment of the 3rd argument
7629 for __builtin_*_overflow_p. */
7632 magic_varargs_p (tree fn
)
7634 if (DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
7635 switch (DECL_FUNCTION_CODE (fn
))
7637 case BUILT_IN_CLASSIFY_TYPE
:
7638 case BUILT_IN_CONSTANT_P
:
7639 case BUILT_IN_NEXT_ARG
:
7640 case BUILT_IN_VA_START
:
7643 case BUILT_IN_ADD_OVERFLOW_P
:
7644 case BUILT_IN_SUB_OVERFLOW_P
:
7645 case BUILT_IN_MUL_OVERFLOW_P
:
7649 return lookup_attribute ("type generic",
7650 TYPE_ATTRIBUTES (TREE_TYPE (fn
))) != 0;
7656 /* Returns the decl of the dispatcher function if FN is a function version. */
7659 get_function_version_dispatcher (tree fn
)
7661 tree dispatcher_decl
= NULL
;
7663 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
7664 && DECL_FUNCTION_VERSIONED (fn
));
7666 gcc_assert (targetm
.get_function_versions_dispatcher
);
7667 dispatcher_decl
= targetm
.get_function_versions_dispatcher (fn
);
7669 if (dispatcher_decl
== NULL
)
7671 error_at (input_location
, "use of multiversioned function "
7672 "without a default");
7676 retrofit_lang_decl (dispatcher_decl
);
7677 gcc_assert (dispatcher_decl
!= NULL
);
7678 return dispatcher_decl
;
7681 /* fn is a function version dispatcher that is marked used. Mark all the
7682 semantically identical function versions it will dispatch as used. */
7685 mark_versions_used (tree fn
)
7687 struct cgraph_node
*node
;
7688 struct cgraph_function_version_info
*node_v
;
7689 struct cgraph_function_version_info
*it_v
;
7691 gcc_assert (TREE_CODE (fn
) == FUNCTION_DECL
);
7693 node
= cgraph_node::get (fn
);
7697 gcc_assert (node
->dispatcher_function
);
7699 node_v
= node
->function_version ();
7703 /* All semantically identical versions are chained. Traverse and mark each
7704 one of them as used. */
7705 it_v
= node_v
->next
;
7706 while (it_v
!= NULL
)
7708 mark_used (it_v
->this_node
->decl
);
7713 /* Build a call to "the copy constructor" for the type of A, even if it
7714 wouldn't be selected by normal overload resolution. Used for
7718 call_copy_ctor (tree a
, tsubst_flags_t complain
)
7720 tree ctype
= TYPE_MAIN_VARIANT (TREE_TYPE (a
));
7721 tree binfo
= TYPE_BINFO (ctype
);
7722 tree copy
= get_copy_ctor (ctype
, complain
);
7723 copy
= build_baselink (binfo
, binfo
, copy
, NULL_TREE
);
7724 tree ob
= build_dummy_object (ctype
);
7725 vec
<tree
, va_gc
>* args
= make_tree_vector_single (a
);
7726 tree r
= build_new_method_call (ob
, copy
, &args
, NULL_TREE
,
7727 LOOKUP_NORMAL
, NULL
, complain
);
7728 release_tree_vector (args
);
7732 /* Return true iff T refers to a base field. */
7735 is_base_field_ref (tree t
)
7738 if (TREE_CODE (t
) == ADDR_EXPR
)
7739 t
= TREE_OPERAND (t
, 0);
7740 if (TREE_CODE (t
) == COMPONENT_REF
)
7741 t
= TREE_OPERAND (t
, 1);
7742 if (TREE_CODE (t
) == FIELD_DECL
)
7743 return DECL_FIELD_IS_BASE (t
);
7747 /* We can't elide a copy from a function returning by value to a base
7748 subobject, as the callee might clobber tail padding. Return true iff this
7749 could be that case. */
7752 unsafe_copy_elision_p (tree target
, tree exp
)
7754 /* Copy elision only happens with a TARGET_EXPR. */
7755 if (TREE_CODE (exp
) != TARGET_EXPR
)
7757 tree type
= TYPE_MAIN_VARIANT (TREE_TYPE (exp
));
7758 /* It's safe to elide the copy for a class with no tail padding. */
7759 if (tree_int_cst_equal (TYPE_SIZE (type
), CLASSTYPE_SIZE (type
)))
7761 /* It's safe to elide the copy if we aren't initializing a base object. */
7762 if (!is_base_field_ref (target
))
7764 tree init
= TARGET_EXPR_INITIAL (exp
);
7765 /* build_compound_expr pushes COMPOUND_EXPR inside TARGET_EXPR. */
7766 while (TREE_CODE (init
) == COMPOUND_EXPR
)
7767 init
= TREE_OPERAND (init
, 1);
7768 if (TREE_CODE (init
) == COND_EXPR
)
7770 /* We'll end up copying from each of the arms of the COND_EXPR directly
7771 into the target, so look at them. */
7772 if (tree op
= TREE_OPERAND (init
, 1))
7773 if (unsafe_copy_elision_p (target
, op
))
7775 return unsafe_copy_elision_p (target
, TREE_OPERAND (init
, 2));
7777 return (TREE_CODE (init
) == AGGR_INIT_EXPR
7778 && !AGGR_INIT_VIA_CTOR_P (init
));
7781 /* True iff C is a conversion that binds a reference to a prvalue. */
7784 conv_binds_ref_to_prvalue (conversion
*c
)
7786 if (c
->kind
!= ck_ref_bind
)
7788 if (c
->need_temporary_p
)
7791 c
= next_conversion (c
);
7793 if (c
->kind
== ck_rvalue
)
7795 if (c
->kind
== ck_user
&& !TYPE_REF_P (c
->type
))
7797 if (c
->kind
== ck_identity
&& c
->u
.expr
7798 && TREE_CODE (c
->u
.expr
) == TARGET_EXPR
)
7804 /* Call the trivial destructor for INSTANCE, which can be either an lvalue of
7805 class type or a pointer to class type. */
7808 build_trivial_dtor_call (tree instance
)
7810 gcc_assert (!is_dummy_object (instance
));
7812 if (!flag_lifetime_dse
)
7815 return fold_convert (void_type_node
, instance
);
7818 if (INDIRECT_TYPE_P (TREE_TYPE (instance
)))
7820 if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (instance
))))
7822 instance
= cp_build_fold_indirect_ref (instance
);
7825 /* A trivial destructor should still clobber the object. */
7826 tree clobber
= build_clobber (TREE_TYPE (instance
));
7827 return build2 (MODIFY_EXPR
, void_type_node
,
7831 /* Subroutine of the various build_*_call functions. Overload resolution
7832 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7833 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7834 bitmask of various LOOKUP_* flags which apply to the call itself. */
7837 build_over_call (struct z_candidate
*cand
, int flags
, tsubst_flags_t complain
)
7840 const vec
<tree
, va_gc
> *args
= cand
->args
;
7841 tree first_arg
= cand
->first_arg
;
7842 conversion
**convs
= cand
->convs
;
7844 tree parm
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
7849 unsigned int arg_index
= 0;
7853 bool already_used
= false;
7855 /* In a template, there is no need to perform all of the work that
7856 is normally done. We are only interested in the type of the call
7857 expression, i.e., the return type of the function. Any semantic
7858 errors will be deferred until the template is instantiated. */
7859 if (processing_template_decl
)
7863 const tree
*argarray
;
7866 if (undeduced_auto_decl (fn
))
7867 mark_used (fn
, complain
);
7869 /* Otherwise set TREE_USED for the benefit of -Wunused-function.
7873 return_type
= TREE_TYPE (TREE_TYPE (fn
));
7874 nargs
= vec_safe_length (args
);
7875 if (first_arg
== NULL_TREE
)
7876 argarray
= args
->address ();
7884 alcarray
= XALLOCAVEC (tree
, nargs
);
7885 alcarray
[0] = build_this (first_arg
);
7886 FOR_EACH_VEC_SAFE_ELT (args
, ix
, arg
)
7887 alcarray
[ix
+ 1] = arg
;
7888 argarray
= alcarray
;
7891 addr
= build_addr_func (fn
, complain
);
7892 if (addr
== error_mark_node
)
7893 return error_mark_node
;
7894 expr
= build_call_array_loc (input_location
, return_type
,
7895 addr
, nargs
, argarray
);
7896 if (TREE_THIS_VOLATILE (fn
) && cfun
)
7897 current_function_returns_abnormally
= 1;
7898 return convert_from_reference (expr
);
7901 /* Give any warnings we noticed during overload resolution. */
7902 if (cand
->warnings
&& (complain
& tf_warning
))
7904 struct candidate_warning
*w
;
7905 for (w
= cand
->warnings
; w
; w
= w
->next
)
7906 joust (cand
, w
->loser
, 1, complain
);
7909 /* Core issue 2327: P0135 doesn't say how to handle the case where the
7910 argument to the copy constructor ends up being a prvalue after
7911 conversion. Let's do the normal processing, but pretend we aren't
7912 actually using the copy constructor. */
7913 bool force_elide
= false;
7914 if (cxx_dialect
>= cxx17
7915 && cand
->num_convs
== 1
7916 && DECL_COMPLETE_CONSTRUCTOR_P (fn
)
7917 && (DECL_COPY_CONSTRUCTOR_P (fn
)
7918 || DECL_MOVE_CONSTRUCTOR_P (fn
))
7919 && conv_binds_ref_to_prvalue (convs
[0]))
7922 goto not_really_used
;
7925 /* OK, we're actually calling this inherited constructor; set its deletedness
7926 appropriately. We can get away with doing this here because calling is
7927 the only way to refer to a constructor. */
7928 if (DECL_INHERITED_CTOR (fn
))
7929 deduce_inheriting_ctor (fn
);
7931 /* Make =delete work with SFINAE. */
7932 if (DECL_DELETED_FN (fn
))
7934 if (complain
& tf_error
)
7936 return error_mark_node
;
7939 if (DECL_FUNCTION_MEMBER_P (fn
))
7942 /* If FN is a template function, two cases must be considered.
7947 template <class T> void f();
7949 template <class T> struct B {
7953 struct C : A, B<int> {
7955 using B<int>::g; // #2
7958 In case #1 where `A::f' is a member template, DECL_ACCESS is
7959 recorded in the primary template but not in its specialization.
7960 We check access of FN using its primary template.
7962 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7963 because it is a member of class template B, DECL_ACCESS is
7964 recorded in the specialization `B<int>::g'. We cannot use its
7965 primary template because `B<T>::g' and `B<int>::g' may have
7966 different access. */
7967 if (DECL_TEMPLATE_INFO (fn
)
7968 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn
)))
7969 access_fn
= DECL_TI_TEMPLATE (fn
);
7972 if (!perform_or_defer_access_check (cand
->access_path
, access_fn
,
7974 return error_mark_node
;
7977 /* If we're checking for implicit delete, don't bother with argument
7979 if (flags
& LOOKUP_SPECULATIVE
)
7981 if (cand
->viable
== 1)
7983 else if (!(complain
& tf_error
))
7984 /* Reject bad conversions now. */
7985 return error_mark_node
;
7986 /* else continue to get conversion error. */
7991 /* N3276 magic doesn't apply to nested calls. */
7992 tsubst_flags_t decltype_flag
= (complain
& tf_decltype
);
7993 complain
&= ~tf_decltype
;
7994 /* No-Cleanup doesn't apply to nested calls either. */
7995 tsubst_flags_t no_cleanup_complain
= complain
;
7996 complain
&= ~tf_no_cleanup
;
7998 /* Find maximum size of vector to hold converted arguments. */
7999 parmlen
= list_length (parm
);
8000 nargs
= vec_safe_length (args
) + (first_arg
!= NULL_TREE
? 1 : 0);
8001 if (parmlen
> nargs
)
8003 argarray
= XALLOCAVEC (tree
, nargs
);
8005 /* The implicit parameters to a constructor are not considered by overload
8006 resolution, and must be of the proper type. */
8007 if (DECL_CONSTRUCTOR_P (fn
))
8010 if (first_arg
!= NULL_TREE
)
8012 object_arg
= first_arg
;
8013 first_arg
= NULL_TREE
;
8017 object_arg
= (*args
)[arg_index
];
8020 argarray
[j
++] = build_this (object_arg
);
8021 parm
= TREE_CHAIN (parm
);
8022 /* We should never try to call the abstract constructor. */
8023 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn
));
8025 if (DECL_HAS_VTT_PARM_P (fn
))
8027 argarray
[j
++] = (*args
)[arg_index
];
8029 parm
= TREE_CHAIN (parm
);
8032 if (flags
& LOOKUP_PREFER_RVALUE
)
8034 /* The implicit move specified in 15.8.3/3 fails "...if the type of
8035 the first parameter of the selected constructor is not an rvalue
8036 reference to the object's type (possibly cv-qualified)...." */
8037 gcc_assert (!(complain
& tf_error
));
8038 tree ptype
= convs
[0]->type
;
8039 if (!TYPE_REF_P (ptype
)
8040 || !TYPE_REF_IS_RVALUE (ptype
)
8041 || CONVERSION_RANK (convs
[0]) > cr_exact
)
8042 return error_mark_node
;
8045 /* Bypass access control for 'this' parameter. */
8046 else if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
)
8048 tree parmtype
= TREE_VALUE (parm
);
8049 tree arg
= build_this (first_arg
!= NULL_TREE
8051 : (*args
)[arg_index
]);
8052 tree argtype
= TREE_TYPE (arg
);
8056 if (arg
== error_mark_node
)
8057 return error_mark_node
;
8059 if (convs
[i
]->bad_p
)
8061 if (complain
& tf_error
)
8063 auto_diagnostic_group d
;
8064 if (permerror (input_location
, "passing %qT as %<this%> "
8065 "argument discards qualifiers",
8066 TREE_TYPE (argtype
)))
8067 inform (DECL_SOURCE_LOCATION (fn
), " in call to %qD", fn
);
8070 return error_mark_node
;
8073 /* See if the function member or the whole class type is declared
8074 final and the call can be devirtualized. */
8075 if (DECL_FINAL_P (fn
)
8076 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn
))))
8077 flags
|= LOOKUP_NONVIRTUAL
;
8079 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
8080 X is called for an object that is not of type X, or of a type
8081 derived from X, the behavior is undefined.
8083 So we can assume that anything passed as 'this' is non-null, and
8084 optimize accordingly. */
8085 gcc_assert (TYPE_PTR_P (parmtype
));
8086 /* Convert to the base in which the function was declared. */
8087 gcc_assert (cand
->conversion_path
!= NULL_TREE
);
8088 converted_arg
= build_base_path (PLUS_EXPR
,
8090 cand
->conversion_path
,
8092 /* Check that the base class is accessible. */
8093 if (!accessible_base_p (TREE_TYPE (argtype
),
8094 BINFO_TYPE (cand
->conversion_path
), true))
8096 if (complain
& tf_error
)
8097 error ("%qT is not an accessible base of %qT",
8098 BINFO_TYPE (cand
->conversion_path
),
8099 TREE_TYPE (argtype
));
8101 return error_mark_node
;
8103 /* If fn was found by a using declaration, the conversion path
8104 will be to the derived class, not the base declaring fn. We
8105 must convert from derived to base. */
8106 base_binfo
= lookup_base (TREE_TYPE (TREE_TYPE (converted_arg
)),
8107 TREE_TYPE (parmtype
), ba_unique
,
8109 converted_arg
= build_base_path (PLUS_EXPR
, converted_arg
,
8110 base_binfo
, 1, complain
);
8112 argarray
[j
++] = converted_arg
;
8113 parm
= TREE_CHAIN (parm
);
8114 if (first_arg
!= NULL_TREE
)
8115 first_arg
= NULL_TREE
;
8122 gcc_assert (first_arg
== NULL_TREE
);
8123 for (; arg_index
< vec_safe_length (args
) && parm
;
8124 parm
= TREE_CHAIN (parm
), ++arg_index
, ++i
)
8126 tree type
= TREE_VALUE (parm
);
8127 tree arg
= (*args
)[arg_index
];
8128 bool conversion_warning
= true;
8132 /* If the argument is NULL and used to (implicitly) instantiate a
8133 template function (and bind one of the template arguments to
8134 the type of 'long int'), we don't want to warn about passing NULL
8135 to non-pointer argument.
8136 For example, if we have this template function:
8138 template<typename T> void func(T x) {}
8140 we want to warn (when -Wconversion is enabled) in this case:
8146 but not in this case:
8152 if (null_node_p (arg
)
8153 && DECL_TEMPLATE_INFO (fn
)
8154 && cand
->template_decl
8155 && !(flags
& LOOKUP_EXPLICIT_TMPL_ARGS
))
8156 conversion_warning
= false;
8158 /* Warn about initializer_list deduction that isn't currently in the
8160 if (cxx_dialect
> cxx98
8161 && flag_deduce_init_list
8162 && cand
->template_decl
8163 && is_std_init_list (non_reference (type
))
8164 && BRACE_ENCLOSED_INITIALIZER_P (arg
))
8166 tree tmpl
= TI_TEMPLATE (cand
->template_decl
);
8167 tree realparm
= chain_index (j
, DECL_ARGUMENTS (cand
->fn
));
8168 tree patparm
= get_pattern_parm (realparm
, tmpl
);
8169 tree pattype
= TREE_TYPE (patparm
);
8170 if (PACK_EXPANSION_P (pattype
))
8171 pattype
= PACK_EXPANSION_PATTERN (pattype
);
8172 pattype
= non_reference (pattype
);
8174 if (TREE_CODE (pattype
) == TEMPLATE_TYPE_PARM
8175 && (cand
->explicit_targs
== NULL_TREE
8176 || (TREE_VEC_LENGTH (cand
->explicit_targs
)
8177 <= TEMPLATE_TYPE_IDX (pattype
))))
8179 pedwarn (input_location
, 0, "deducing %qT as %qT",
8180 non_reference (TREE_TYPE (patparm
)),
8181 non_reference (type
));
8182 pedwarn (DECL_SOURCE_LOCATION (cand
->fn
), 0,
8183 " in call to %qD", cand
->fn
);
8184 pedwarn (input_location
, 0,
8185 " (you can disable this with -fno-deduce-init-list)");
8189 /* Set user_conv_p on the argument conversions, so rvalue/base handling
8190 knows not to allow any more UDCs. This needs to happen after we
8191 process cand->warnings. */
8192 if (flags
& LOOKUP_NO_CONVERSION
)
8193 conv
->user_conv_p
= true;
8195 tsubst_flags_t arg_complain
= complain
;
8196 if (!conversion_warning
)
8197 arg_complain
&= ~tf_warning
;
8199 val
= convert_like_with_context (conv
, arg
, fn
, i
- is_method
,
8201 val
= convert_for_arg_passing (type
, val
, arg_complain
);
8203 if (val
== error_mark_node
)
8204 return error_mark_node
;
8206 argarray
[j
++] = val
;
8209 /* Default arguments */
8210 for (; parm
&& parm
!= void_list_node
; parm
= TREE_CHAIN (parm
), i
++)
8212 if (TREE_VALUE (parm
) == error_mark_node
)
8213 return error_mark_node
;
8214 val
= convert_default_arg (TREE_VALUE (parm
),
8215 TREE_PURPOSE (parm
),
8218 if (val
== error_mark_node
)
8219 return error_mark_node
;
8220 argarray
[j
++] = val
;
8224 int magic
= magic_varargs_p (fn
);
8225 for (; arg_index
< vec_safe_length (args
); ++arg_index
)
8227 tree a
= (*args
)[arg_index
];
8228 if ((magic
== 3 && arg_index
== 2) || magic
== 2)
8230 /* Do no conversions for certain magic varargs. */
8231 a
= mark_type_use (a
);
8232 if (TREE_CODE (a
) == FUNCTION_DECL
&& reject_gcc_builtin (a
))
8233 return error_mark_node
;
8235 else if (magic
!= 0)
8236 /* For other magic varargs only do decay_conversion. */
8237 a
= decay_conversion (a
, complain
);
8238 else if (DECL_CONSTRUCTOR_P (fn
)
8239 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn
),
8242 /* Avoid infinite recursion trying to call A(...). */
8243 if (complain
& tf_error
)
8244 /* Try to call the actual copy constructor for a good error. */
8245 call_copy_ctor (a
, complain
);
8246 return error_mark_node
;
8249 a
= convert_arg_to_ellipsis (a
, complain
);
8250 if (a
== error_mark_node
)
8251 return error_mark_node
;
8255 gcc_assert (j
<= nargs
);
8258 /* Avoid to do argument-transformation, if warnings for format, and for
8259 nonnull are disabled. Just in case that at least one of them is active
8260 the check_function_arguments function might warn about something. */
8262 bool warned_p
= false;
8265 || warn_suggest_attribute_format
8268 tree
*fargs
= (!nargs
? argarray
8269 : (tree
*) alloca (nargs
* sizeof (tree
)));
8270 for (j
= 0; j
< nargs
; j
++)
8272 /* For -Wformat undo the implicit passing by hidden reference
8273 done by convert_arg_to_ellipsis. */
8274 if (TREE_CODE (argarray
[j
]) == ADDR_EXPR
8275 && TYPE_REF_P (TREE_TYPE (argarray
[j
])))
8276 fargs
[j
] = TREE_OPERAND (argarray
[j
], 0);
8278 fargs
[j
] = argarray
[j
];
8281 warned_p
= check_function_arguments (input_location
, fn
, TREE_TYPE (fn
),
8282 nargs
, fargs
, NULL
);
8285 if (DECL_INHERITED_CTOR (fn
))
8287 /* Check for passing ellipsis arguments to an inherited constructor. We
8288 could handle this by open-coding the inherited constructor rather than
8289 defining it, but let's not bother now. */
8290 if (!cp_unevaluated_operand
8292 && cand
->convs
[cand
->num_convs
-1]->ellipsis_p
)
8294 if (complain
& tf_error
)
8296 sorry ("passing arguments to ellipsis of inherited constructor "
8298 inform (DECL_SOURCE_LOCATION (cand
->fn
), "declared here");
8300 return error_mark_node
;
8303 /* A base constructor inheriting from a virtual base doesn't get the
8304 inherited arguments, just this and __vtt. */
8305 if (ctor_omit_inherited_parms (fn
))
8309 /* Avoid actually calling copy constructors and copy assignment operators,
8312 if (! flag_elide_constructors
&& !force_elide
)
8313 /* Do things the hard way. */;
8314 else if (cand
->num_convs
== 1
8315 && (DECL_COPY_CONSTRUCTOR_P (fn
)
8316 || DECL_MOVE_CONSTRUCTOR_P (fn
))
8317 /* It's unsafe to elide the constructor when handling
8318 a noexcept-expression, it may evaluate to the wrong
8319 value (c++/53025). */
8320 && (force_elide
|| cp_noexcept_operand
== 0))
8323 tree arg
= argarray
[num_artificial_parms_for (fn
)];
8325 bool trivial
= trivial_fn_p (fn
);
8327 /* Pull out the real argument, disregarding const-correctness. */
8329 /* Strip the reference binding for the constructor parameter. */
8330 if (CONVERT_EXPR_P (targ
)
8331 && TYPE_REF_P (TREE_TYPE (targ
)))
8332 targ
= TREE_OPERAND (targ
, 0);
8333 /* But don't strip any other reference bindings; binding a temporary to a
8334 reference prevents copy elision. */
8335 while ((CONVERT_EXPR_P (targ
)
8336 && !TYPE_REF_P (TREE_TYPE (targ
)))
8337 || TREE_CODE (targ
) == NON_LVALUE_EXPR
)
8338 targ
= TREE_OPERAND (targ
, 0);
8339 if (TREE_CODE (targ
) == ADDR_EXPR
)
8341 targ
= TREE_OPERAND (targ
, 0);
8342 if (!same_type_ignoring_top_level_qualifiers_p
8343 (TREE_TYPE (TREE_TYPE (arg
)), TREE_TYPE (targ
)))
8352 arg
= cp_build_fold_indirect_ref (arg
);
8354 /* In C++17 we shouldn't be copying a TARGET_EXPR except into a base
8356 if (CHECKING_P
&& cxx_dialect
>= cxx17
)
8357 gcc_assert (TREE_CODE (arg
) != TARGET_EXPR
8359 /* It's from binding the ref parm to a packed field. */
8360 || convs
[0]->need_temporary_p
8362 /* See unsafe_copy_elision_p. */
8363 || DECL_BASE_CONSTRUCTOR_P (fn
));
8366 bool unsafe
= unsafe_copy_elision_p (fa
, arg
);
8367 bool eliding_temp
= (TREE_CODE (arg
) == TARGET_EXPR
&& !unsafe
);
8369 /* [class.copy]: the copy constructor is implicitly defined even if the
8370 implementation elided its use. But don't warn about deprecation when
8371 eliding a temporary, as then no copy is actually performed. */
8372 warning_sentinel
s (warn_deprecated_copy
, eliding_temp
);
8374 /* The language says this isn't called. */;
8377 if (!mark_used (fn
, complain
) && !(complain
& tf_error
))
8378 return error_mark_node
;
8379 already_used
= true;
8382 cp_warn_deprecated_use (fn
, complain
);
8384 /* If we're creating a temp and we already have one, don't create a
8385 new one. If we're not creating a temp but we get one, use
8386 INIT_EXPR to collapse the temp into our target. Otherwise, if the
8387 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
8388 temp or an INIT_EXPR otherwise. */
8389 if (is_dummy_object (fa
))
8391 if (TREE_CODE (arg
) == TARGET_EXPR
)
8394 return force_target_expr (DECL_CONTEXT (fn
), arg
, complain
);
8396 else if ((trivial
|| TREE_CODE (arg
) == TARGET_EXPR
)
8399 tree to
= cp_stabilize_reference (cp_build_fold_indirect_ref (fa
));
8401 val
= build2 (INIT_EXPR
, DECL_CONTEXT (fn
), to
, arg
);
8405 else if (DECL_ASSIGNMENT_OPERATOR_P (fn
)
8406 && DECL_OVERLOADED_OPERATOR_IS (fn
, NOP_EXPR
)
8407 && trivial_fn_p (fn
))
8409 tree to
= cp_stabilize_reference
8410 (cp_build_fold_indirect_ref (argarray
[0]));
8411 tree type
= TREE_TYPE (to
);
8412 tree as_base
= CLASSTYPE_AS_BASE (type
);
8413 tree arg
= argarray
[1];
8414 location_t loc
= cp_expr_loc_or_loc (arg
, input_location
);
8416 if (is_really_empty_class (type
))
8418 /* Avoid copying empty classes. */
8419 val
= build2 (COMPOUND_EXPR
, type
, arg
, to
);
8420 TREE_NO_WARNING (val
) = 1;
8422 else if (tree_int_cst_equal (TYPE_SIZE (type
), TYPE_SIZE (as_base
)))
8424 if (is_std_init_list (type
)
8425 && conv_binds_ref_to_prvalue (convs
[1]))
8426 warning_at (loc
, OPT_Winit_list_lifetime
,
8427 "assignment from temporary initializer_list does not "
8428 "extend the lifetime of the underlying array");
8429 arg
= cp_build_fold_indirect_ref (arg
);
8430 val
= build2 (MODIFY_EXPR
, TREE_TYPE (to
), to
, arg
);
8434 /* We must only copy the non-tail padding parts. */
8436 tree array_type
, alias_set
;
8438 arg2
= TYPE_SIZE_UNIT (as_base
);
8439 arg0
= cp_build_addr_expr (to
, complain
);
8441 array_type
= build_array_type (unsigned_char_type_node
,
8443 (size_binop (MINUS_EXPR
,
8444 arg2
, size_int (1))));
8445 alias_set
= build_int_cst (build_pointer_type (type
), 0);
8446 t
= build2 (MODIFY_EXPR
, void_type_node
,
8447 build2 (MEM_REF
, array_type
, arg0
, alias_set
),
8448 build2 (MEM_REF
, array_type
, arg
, alias_set
));
8449 val
= build2 (COMPOUND_EXPR
, TREE_TYPE (to
), t
, to
);
8450 TREE_NO_WARNING (val
) = 1;
8453 cp_warn_deprecated_use (fn
, complain
);
8457 else if (trivial_fn_p (fn
))
8459 if (DECL_DESTRUCTOR_P (fn
))
8460 return build_trivial_dtor_call (argarray
[0]);
8461 else if (default_ctor_p (fn
))
8463 if (is_dummy_object (argarray
[0]))
8464 return force_target_expr (DECL_CONTEXT (fn
), void_node
,
8465 no_cleanup_complain
);
8467 return cp_build_fold_indirect_ref (argarray
[0]);
8471 gcc_assert (!force_elide
);
8474 && !mark_used (fn
, complain
))
8475 return error_mark_node
;
8477 /* Warn if the built-in writes to an object of a non-trivial type. */
8478 if (warn_class_memaccess
8479 && vec_safe_length (args
) >= 2
8480 && DECL_BUILT_IN_CLASS (fn
) == BUILT_IN_NORMAL
)
8481 maybe_warn_class_memaccess (input_location
, fn
, args
);
8483 if (DECL_VINDEX (fn
) && (flags
& LOOKUP_NONVIRTUAL
) == 0)
8486 tree binfo
= lookup_base (TREE_TYPE (TREE_TYPE (argarray
[0])),
8488 ba_any
, NULL
, complain
);
8489 gcc_assert (binfo
&& binfo
!= error_mark_node
);
8491 argarray
[0] = build_base_path (PLUS_EXPR
, argarray
[0], binfo
, 1,
8493 if (TREE_SIDE_EFFECTS (argarray
[0]))
8494 argarray
[0] = save_expr (argarray
[0]);
8495 t
= build_pointer_type (TREE_TYPE (fn
));
8496 fn
= build_vfn_ref (argarray
[0], DECL_VINDEX (fn
));
8501 fn
= build_addr_func (fn
, complain
);
8502 if (fn
== error_mark_node
)
8503 return error_mark_node
;
8506 tree call
= build_cxx_call (fn
, nargs
, argarray
, complain
|decltype_flag
);
8507 if (call
== error_mark_node
)
8509 if (cand
->flags
& LOOKUP_LIST_INIT_CTOR
)
8511 tree c
= extract_call_expr (call
);
8512 /* build_new_op_1 will clear this when appropriate. */
8513 CALL_EXPR_ORDERED_ARGS (c
) = true;
8517 tree c
= extract_call_expr (call
);
8518 if (TREE_CODE (c
) == CALL_EXPR
)
8519 TREE_NO_WARNING (c
) = 1;
8527 /* Return the DECL of the first non-static subobject of class TYPE
8528 that satisfies the predicate PRED or null if none can be found. */
8530 template <class Predicate
>
8532 first_non_static_field (tree type
, Predicate pred
)
8534 if (!type
|| !CLASS_TYPE_P (type
))
8537 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
8539 if (TREE_CODE (field
) != FIELD_DECL
)
8541 if (TREE_STATIC (field
))
8549 for (tree base_binfo
, binfo
= TYPE_BINFO (type
);
8550 BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
8552 tree base
= TREE_TYPE (base_binfo
);
8555 if (tree field
= first_non_static_field (base
, pred
))
8562 struct NonPublicField
8564 bool operator() (const_tree t
)
8566 return DECL_P (t
) && (TREE_PRIVATE (t
) || TREE_PROTECTED (t
));
8570 /* Return the DECL of the first non-public subobject of class TYPE
8571 or null if none can be found. */
8574 first_non_public_field (tree type
)
8576 return first_non_static_field (type
, NonPublicField ());
8579 struct NonTrivialField
8581 bool operator() (const_tree t
)
8583 return !trivial_type_p (DECL_P (t
) ? TREE_TYPE (t
) : t
);
8587 /* Return the DECL of the first non-trivial subobject of class TYPE
8588 or null if none can be found. */
8591 first_non_trivial_field (tree type
)
8593 return first_non_static_field (type
, NonTrivialField ());
8596 } /* unnamed namespace */
8598 /* Return true if all copy and move assignment operator overloads for
8599 class TYPE are trivial and at least one of them is not deleted and,
8600 when ACCESS is set, accessible. Return false otherwise. Set
8601 HASASSIGN to true when the TYPE has a (not necessarily trivial)
8602 copy or move assignment. */
8605 has_trivial_copy_assign_p (tree type
, bool access
, bool *hasassign
)
8607 tree fns
= get_class_binding (type
, assign_op_identifier
);
8608 bool all_trivial
= true;
8610 /* Iterate over overloads of the assignment operator, checking
8611 accessible copy assignments for triviality. */
8613 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8617 /* Skip operators that aren't copy assignments. */
8621 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8622 || accessible_p (TYPE_BINFO (type
), f
, true));
8624 /* Skip template assignment operators and deleted functions. */
8625 if (TREE_CODE (f
) != FUNCTION_DECL
|| DECL_DELETED_FN (f
))
8631 if (!accessible
|| !trivial_fn_p (f
))
8632 all_trivial
= false;
8634 /* Break early when both properties have been determined. */
8635 if (*hasassign
&& !all_trivial
)
8639 /* Return true if they're all trivial and one of the expressions
8640 TYPE() = TYPE() or TYPE() = (TYPE&)() is valid. */
8641 tree ref
= cp_build_reference_type (type
, false);
8643 && (is_trivially_xible (MODIFY_EXPR
, type
, type
)
8644 || is_trivially_xible (MODIFY_EXPR
, type
, ref
)));
8647 /* Return true if all copy and move ctor overloads for class TYPE are
8648 trivial and at least one of them is not deleted and, when ACCESS is
8649 set, accessible. Return false otherwise. Set each element of HASCTOR[]
8650 to true when the TYPE has a (not necessarily trivial) default and copy
8651 (or move) ctor, respectively. */
8654 has_trivial_copy_p (tree type
, bool access
, bool hasctor
[2])
8656 tree fns
= get_class_binding (type
, complete_ctor_identifier
);
8657 bool all_trivial
= true;
8659 for (ovl_iterator
oi (fns
); oi
; ++oi
)
8663 /* Skip template constructors. */
8664 if (TREE_CODE (f
) != FUNCTION_DECL
)
8667 bool cpy_or_move_ctor_p
= copy_fn_p (f
);
8669 /* Skip ctors other than default, copy, and move. */
8670 if (!cpy_or_move_ctor_p
&& !default_ctor_p (f
))
8673 if (DECL_DELETED_FN (f
))
8676 bool accessible
= (!access
|| !(TREE_PRIVATE (f
) || TREE_PROTECTED (f
))
8677 || accessible_p (TYPE_BINFO (type
), f
, true));
8680 hasctor
[cpy_or_move_ctor_p
] = true;
8682 if (cpy_or_move_ctor_p
&& (!accessible
|| !trivial_fn_p (f
)))
8683 all_trivial
= false;
8685 /* Break early when both properties have been determined. */
8686 if (hasctor
[0] && hasctor
[1] && !all_trivial
)
8693 /* Issue a warning on a call to the built-in function FNDECL if it is
8694 a raw memory write whose destination is not an object of (something
8695 like) trivial or standard layout type with a non-deleted assignment
8696 and copy ctor. Detects const correctness violations, corrupting
8697 references, virtual table pointers, and bypassing non-trivial
8701 maybe_warn_class_memaccess (location_t loc
, tree fndecl
,
8702 const vec
<tree
, va_gc
> *args
)
8704 /* Except for bcopy where it's second, the destination pointer is
8705 the first argument for all functions handled here. Compute
8706 the index of the destination and source arguments. */
8707 unsigned dstidx
= DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_BCOPY
;
8708 unsigned srcidx
= !dstidx
;
8710 tree dest
= (*args
)[dstidx
];
8711 if (!TREE_TYPE (dest
) || !INDIRECT_TYPE_P (TREE_TYPE (dest
)))
8714 tree srctype
= NULL_TREE
;
8716 /* Determine the type of the pointed-to object and whether it's
8717 a complete class type. */
8718 tree desttype
= TREE_TYPE (TREE_TYPE (dest
));
8720 if (!desttype
|| !COMPLETE_TYPE_P (desttype
) || !CLASS_TYPE_P (desttype
))
8723 /* Check to see if the raw memory call is made by a non-static member
8724 function with THIS as the destination argument for the destination
8725 type. If so, and if the class has no non-trivial bases or members,
8726 be more permissive. */
8727 if (current_function_decl
8728 && DECL_NONSTATIC_MEMBER_FUNCTION_P (current_function_decl
)
8729 && is_this_parameter (tree_strip_nop_conversions (dest
)))
8731 tree ctx
= DECL_CONTEXT (current_function_decl
);
8732 bool special
= same_type_ignoring_top_level_qualifiers_p (ctx
, desttype
);
8733 tree binfo
= TYPE_BINFO (ctx
);
8736 && !BINFO_VTABLE (binfo
)
8737 && !first_non_trivial_field (desttype
))
8741 /* True if the class is trivial. */
8742 bool trivial
= trivial_type_p (desttype
);
8744 /* Set to true if DESTYPE has an accessible copy assignment. */
8745 bool hasassign
= false;
8746 /* True if all of the class' overloaded copy assignment operators
8747 are all trivial (and not deleted) and at least one of them is
8749 bool trivassign
= has_trivial_copy_assign_p (desttype
, true, &hasassign
);
8751 /* Set to true if DESTTYPE has an accessible default and copy ctor,
8753 bool hasctors
[2] = { false, false };
8755 /* True if all of the class' overloaded copy constructors are all
8756 trivial (and not deleted) and at least one of them is accessible. */
8757 bool trivcopy
= has_trivial_copy_p (desttype
, true, hasctors
);
8759 /* Set FLD to the first private/protected member of the class. */
8760 tree fld
= trivial
? first_non_public_field (desttype
) : NULL_TREE
;
8762 /* The warning format string. */
8763 const char *warnfmt
= NULL
;
8764 /* A suggested alternative to offer instead of the raw memory call.
8765 Empty string when none can be come up with. */
8766 const char *suggest
= "";
8767 bool warned
= false;
8769 switch (DECL_FUNCTION_CODE (fndecl
))
8771 case BUILT_IN_MEMSET
:
8772 if (!integer_zerop (maybe_constant_value ((*args
)[1])))
8774 /* Diagnose setting non-copy-assignable or non-trivial types,
8775 or types with a private member, to (potentially) non-zero
8776 bytes. Since the value of the bytes being written is unknown,
8777 suggest using assignment instead (if one exists). Also warn
8778 for writes into objects for which zero-initialization doesn't
8779 mean all bits clear (pointer-to-member data, where null is all
8780 bits set). Since the value being written is (most likely)
8781 non-zero, simply suggest assignment (but not copy assignment). */
8782 suggest
= "; use assignment instead";
8784 warnfmt
= G_("%qD writing to an object of type %#qT with "
8785 "no trivial copy-assignment");
8787 warnfmt
= G_("%qD writing to an object of non-trivial type %#qT%s");
8790 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8791 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8792 "%qD writing to an object of type %#qT with "
8794 fndecl
, desttype
, access
, fld
);
8796 else if (!zero_init_p (desttype
))
8797 warnfmt
= G_("%qD writing to an object of type %#qT containing "
8798 "a pointer to data member%s");
8804 case BUILT_IN_BZERO
:
8805 /* Similarly to the above, diagnose clearing non-trivial or non-
8806 standard layout objects, or objects of types with no assignmenmt.
8807 Since the value being written is known to be zero, suggest either
8808 copy assignment, copy ctor, or default ctor as an alternative,
8809 depending on what's available. */
8811 if (hasassign
&& hasctors
[0])
8812 suggest
= G_("; use assignment or value-initialization instead");
8814 suggest
= G_("; use assignment instead");
8815 else if (hasctors
[0])
8816 suggest
= G_("; use value-initialization instead");
8819 warnfmt
= G_("%qD clearing an object of type %#qT with "
8820 "no trivial copy-assignment%s");
8822 warnfmt
= G_("%qD clearing an object of non-trivial type %#qT%s");
8823 else if (!zero_init_p (desttype
))
8824 warnfmt
= G_("%qD clearing an object of type %#qT containing "
8825 "a pointer-to-member%s");
8828 case BUILT_IN_BCOPY
:
8829 case BUILT_IN_MEMCPY
:
8830 case BUILT_IN_MEMMOVE
:
8831 case BUILT_IN_MEMPCPY
:
8832 /* Determine the type of the source object. */
8833 srctype
= TREE_TYPE ((*args
)[srcidx
]);
8834 if (!srctype
|| !INDIRECT_TYPE_P (srctype
))
8835 srctype
= void_type_node
;
8837 srctype
= TREE_TYPE (srctype
);
8839 /* Since it's impossible to determine wheter the byte copy is
8840 being used in place of assignment to an existing object or
8841 as a substitute for initialization, assume it's the former.
8842 Determine the best alternative to use instead depending on
8843 what's not deleted. */
8844 if (hasassign
&& hasctors
[1])
8845 suggest
= G_("; use copy-assignment or copy-initialization instead");
8847 suggest
= G_("; use copy-assignment instead");
8848 else if (hasctors
[1])
8849 suggest
= G_("; use copy-initialization instead");
8852 warnfmt
= G_("%qD writing to an object of type %#qT with no trivial "
8853 "copy-assignment%s");
8854 else if (!trivially_copyable_p (desttype
))
8855 warnfmt
= G_("%qD writing to an object of non-trivially copyable "
8858 warnfmt
= G_("%qD writing to an object with a deleted copy constructor");
8861 && !VOID_TYPE_P (srctype
)
8862 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8863 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8866 /* Warn when copying into a non-trivial object from an object
8867 of a different type other than void or char. */
8868 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8869 "%qD copying an object of non-trivial type "
8870 "%#qT from an array of %#qT",
8871 fndecl
, desttype
, srctype
);
8874 && !VOID_TYPE_P (srctype
)
8875 && !char_type_p (TYPE_MAIN_VARIANT (srctype
))
8876 && !same_type_ignoring_top_level_qualifiers_p (desttype
,
8879 const char *access
= TREE_PRIVATE (fld
) ? "private" : "protected";
8880 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8881 "%qD copying an object of type %#qT with "
8882 "%qs member %qD from an array of %#qT; use "
8883 "assignment or copy-initialization instead",
8884 fndecl
, desttype
, access
, fld
, srctype
);
8886 else if (!trivial
&& vec_safe_length (args
) > 2)
8888 tree sz
= maybe_constant_value ((*args
)[2]);
8889 if (!tree_fits_uhwi_p (sz
))
8892 /* Finally, warn on partial copies. */
8893 unsigned HOST_WIDE_INT typesize
8894 = tree_to_uhwi (TYPE_SIZE_UNIT (desttype
));
8895 if (unsigned HOST_WIDE_INT partial
= tree_to_uhwi (sz
) % typesize
)
8896 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8897 (typesize
- partial
> 1
8898 ? G_("%qD writing to an object of "
8899 "a non-trivial type %#qT leaves %wu "
8901 : G_("%qD writing to an object of "
8902 "a non-trivial type %#qT leaves %wu "
8904 fndecl
, desttype
, typesize
- partial
);
8908 case BUILT_IN_REALLOC
:
8910 if (!trivially_copyable_p (desttype
))
8911 warnfmt
= G_("%qD moving an object of non-trivially copyable type "
8912 "%#qT; use %<new%> and %<delete%> instead");
8914 warnfmt
= G_("%qD moving an object of type %#qT with deleted copy "
8915 "constructor; use %<new%> and %<delete%> instead");
8916 else if (!get_dtor (desttype
, tf_none
))
8917 warnfmt
= G_("%qD moving an object of type %#qT with deleted "
8921 tree sz
= maybe_constant_value ((*args
)[1]);
8922 if (TREE_CODE (sz
) == INTEGER_CST
8923 && tree_int_cst_lt (sz
, TYPE_SIZE_UNIT (desttype
)))
8924 /* Finally, warn on reallocation into insufficient space. */
8925 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8926 "%qD moving an object of non-trivial type "
8927 "%#qT and size %E into a region of size %E",
8928 fndecl
, desttype
, TYPE_SIZE_UNIT (desttype
),
8940 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8941 warnfmt
, fndecl
, desttype
, suggest
);
8943 warned
= warning_at (loc
, OPT_Wclass_memaccess
,
8944 warnfmt
, fndecl
, desttype
);
8948 inform (location_of (desttype
), "%#qT declared here", desttype
);
8951 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
8952 This function performs no overload resolution, conversion, or other
8953 high-level operations. */
8956 build_cxx_call (tree fn
, int nargs
, tree
*argarray
,
8957 tsubst_flags_t complain
)
8961 /* Remember roughly where this call is. */
8962 location_t loc
= cp_expr_loc_or_loc (fn
, input_location
);
8963 fn
= build_call_a (fn
, nargs
, argarray
);
8964 SET_EXPR_LOCATION (fn
, loc
);
8966 fndecl
= get_callee_fndecl (fn
);
8968 /* Check that arguments to builtin functions match the expectations. */
8970 && !processing_template_decl
8971 && fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
8975 /* We need to take care that values to BUILT_IN_NORMAL
8977 for (i
= 0; i
< nargs
; i
++)
8978 argarray
[i
] = maybe_constant_value (argarray
[i
]);
8980 if (!check_builtin_function_arguments (EXPR_LOCATION (fn
), vNULL
, fndecl
,
8982 return error_mark_node
;
8985 if (VOID_TYPE_P (TREE_TYPE (fn
)))
8988 /* 5.2.2/11: If a function call is a prvalue of object type: if the
8989 function call is either the operand of a decltype-specifier or the
8990 right operand of a comma operator that is the operand of a
8991 decltype-specifier, a temporary object is not introduced for the
8992 prvalue. The type of the prvalue may be incomplete. */
8993 if (!(complain
& tf_decltype
))
8995 fn
= require_complete_type_sfinae (fn
, complain
);
8996 if (fn
== error_mark_node
)
8997 return error_mark_node
;
8999 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn
)))
9001 fn
= build_cplus_new (TREE_TYPE (fn
), fn
, complain
);
9002 maybe_warn_parm_abi (TREE_TYPE (fn
), loc
);
9005 return convert_from_reference (fn
);
9008 /* Returns the value to use for the in-charge parameter when making a
9009 call to a function with the indicated NAME.
9011 FIXME:Can't we find a neater way to do this mapping? */
9014 in_charge_arg_for_name (tree name
)
9016 if (IDENTIFIER_CTOR_P (name
))
9018 if (name
== complete_ctor_identifier
)
9019 return integer_one_node
;
9020 gcc_checking_assert (name
== base_ctor_identifier
);
9024 if (name
== complete_dtor_identifier
)
9025 return integer_two_node
;
9026 else if (name
== deleting_dtor_identifier
)
9027 return integer_three_node
;
9028 gcc_checking_assert (name
== base_dtor_identifier
);
9031 return integer_zero_node
;
9034 /* We've built up a constructor call RET. Complain if it delegates to the
9035 constructor we're currently compiling. */
9038 check_self_delegation (tree ret
)
9040 if (TREE_CODE (ret
) == TARGET_EXPR
)
9041 ret
= TARGET_EXPR_INITIAL (ret
);
9042 tree fn
= cp_get_callee_fndecl_nofold (ret
);
9043 if (fn
&& DECL_ABSTRACT_ORIGIN (fn
) == current_function_decl
)
9044 error ("constructor delegates to itself");
9047 /* Build a call to a constructor, destructor, or an assignment
9048 operator for INSTANCE, an expression with class type. NAME
9049 indicates the special member function to call; *ARGS are the
9050 arguments. ARGS may be NULL. This may change ARGS. BINFO
9051 indicates the base of INSTANCE that is to be passed as the `this'
9052 parameter to the member function called.
9054 FLAGS are the LOOKUP_* flags to use when processing the call.
9056 If NAME indicates a complete object constructor, INSTANCE may be
9057 NULL_TREE. In this case, the caller will call build_cplus_new to
9058 store the newly constructed object into a VAR_DECL. */
9061 build_special_member_call (tree instance
, tree name
, vec
<tree
, va_gc
> **args
,
9062 tree binfo
, int flags
, tsubst_flags_t complain
)
9065 /* The type of the subobject to be constructed or destroyed. */
9067 vec
<tree
, va_gc
> *allocated
= NULL
;
9070 gcc_assert (IDENTIFIER_CDTOR_P (name
) || name
== assign_op_identifier
);
9072 if (error_operand_p (instance
))
9073 return error_mark_node
;
9075 if (IDENTIFIER_DTOR_P (name
))
9077 gcc_assert (args
== NULL
|| vec_safe_is_empty (*args
));
9078 if (!type_build_dtor_call (TREE_TYPE (instance
)))
9079 /* Shortcut to avoid lazy destructor declaration. */
9080 return build_trivial_dtor_call (instance
);
9085 /* Resolve the name. */
9086 if (!complete_type_or_maybe_complain (binfo
, NULL_TREE
, complain
))
9087 return error_mark_node
;
9089 binfo
= TYPE_BINFO (binfo
);
9092 gcc_assert (binfo
!= NULL_TREE
);
9094 class_type
= BINFO_TYPE (binfo
);
9096 /* Handle the special case where INSTANCE is NULL_TREE. */
9097 if (name
== complete_ctor_identifier
&& !instance
)
9098 instance
= build_dummy_object (class_type
);
9101 /* Convert to the base class, if necessary. */
9102 if (!same_type_ignoring_top_level_qualifiers_p
9103 (TREE_TYPE (instance
), BINFO_TYPE (binfo
)))
9105 if (IDENTIFIER_CDTOR_P (name
))
9106 /* For constructors and destructors, either the base is
9107 non-virtual, or it is virtual but we are doing the
9108 conversion from a constructor or destructor for the
9109 complete object. In either case, we can convert
9111 instance
= convert_to_base_statically (instance
, binfo
);
9114 /* However, for assignment operators, we must convert
9115 dynamically if the base is virtual. */
9116 gcc_checking_assert (name
== assign_op_identifier
);
9117 instance
= build_base_path (PLUS_EXPR
, instance
,
9118 binfo
, /*nonnull=*/1, complain
);
9123 gcc_assert (instance
!= NULL_TREE
);
9125 /* In C++17, "If the initializer expression is a prvalue and the
9126 cv-unqualified version of the source type is the same class as the class
9127 of the destination, the initializer expression is used to initialize the
9128 destination object." Handle that here to avoid doing overload
9130 if (cxx_dialect
>= cxx17
9131 && args
&& vec_safe_length (*args
) == 1
9132 && name
== complete_ctor_identifier
)
9134 tree arg
= (**args
)[0];
9136 if (BRACE_ENCLOSED_INITIALIZER_P (arg
)
9137 && !TYPE_HAS_LIST_CTOR (class_type
)
9138 && CONSTRUCTOR_NELTS (arg
) == 1)
9139 arg
= CONSTRUCTOR_ELT (arg
, 0)->value
;
9141 if ((TREE_CODE (arg
) == TARGET_EXPR
9142 || TREE_CODE (arg
) == CONSTRUCTOR
)
9143 && (same_type_ignoring_top_level_qualifiers_p
9144 (class_type
, TREE_TYPE (arg
))))
9146 if (is_dummy_object (instance
))
9148 else if (TREE_CODE (arg
) == TARGET_EXPR
)
9149 TARGET_EXPR_DIRECT_INIT_P (arg
) = true;
9151 if ((complain
& tf_error
)
9152 && (flags
& LOOKUP_DELEGATING_CONS
))
9153 check_self_delegation (arg
);
9154 /* Avoid change of behavior on Wunused-var-2.C. */
9155 instance
= mark_lvalue_use (instance
);
9156 return build2 (INIT_EXPR
, class_type
, instance
, arg
);
9160 fns
= lookup_fnfields (binfo
, name
, 1);
9162 /* When making a call to a constructor or destructor for a subobject
9163 that uses virtual base classes, pass down a pointer to a VTT for
9165 if ((name
== base_ctor_identifier
9166 || name
== base_dtor_identifier
)
9167 && CLASSTYPE_VBASECLASSES (class_type
))
9172 /* If the current function is a complete object constructor
9173 or destructor, then we fetch the VTT directly.
9174 Otherwise, we look it up using the VTT we were given. */
9175 vtt
= DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type
));
9176 vtt
= decay_conversion (vtt
, complain
);
9177 if (vtt
== error_mark_node
)
9178 return error_mark_node
;
9179 vtt
= build_if_in_charge (vtt
, current_vtt_parm
);
9180 if (BINFO_SUBVTT_INDEX (binfo
))
9181 sub_vtt
= fold_build_pointer_plus (vtt
, BINFO_SUBVTT_INDEX (binfo
));
9187 allocated
= make_tree_vector ();
9191 vec_safe_insert (*args
, 0, sub_vtt
);
9194 ret
= build_new_method_call (instance
, fns
, args
,
9195 TYPE_BINFO (BINFO_TYPE (binfo
)),
9199 if (allocated
!= NULL
)
9200 release_tree_vector (allocated
);
9202 if ((complain
& tf_error
)
9203 && (flags
& LOOKUP_DELEGATING_CONS
)
9204 && name
== complete_ctor_identifier
)
9205 check_self_delegation (ret
);
9210 /* Return the NAME, as a C string. The NAME indicates a function that
9211 is a member of TYPE. *FREE_P is set to true if the caller must
9212 free the memory returned.
9214 Rather than go through all of this, we should simply set the names
9215 of constructors and destructors appropriately, and dispense with
9216 ctor_identifier, dtor_identifier, etc. */
9219 name_as_c_string (tree name
, tree type
, bool *free_p
)
9221 const char *pretty_name
;
9223 /* Assume that we will not allocate memory. */
9225 /* Constructors and destructors are special. */
9226 if (IDENTIFIER_CDTOR_P (name
))
9229 = identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type
)));
9230 /* For a destructor, add the '~'. */
9231 if (IDENTIFIER_DTOR_P (name
))
9233 pretty_name
= concat ("~", pretty_name
, NULL
);
9234 /* Remember that we need to free the memory allocated. */
9238 else if (IDENTIFIER_CONV_OP_P (name
))
9240 pretty_name
= concat ("operator ",
9241 type_as_string_translate (TREE_TYPE (name
),
9242 TFF_PLAIN_IDENTIFIER
),
9244 /* Remember that we need to free the memory allocated. */
9248 pretty_name
= identifier_to_locale (IDENTIFIER_POINTER (name
));
9250 return CONST_CAST (char *, pretty_name
);
9253 /* If CANDIDATES contains exactly one candidate, return it, otherwise
9256 static z_candidate
*
9257 single_z_candidate (z_candidate
*candidates
)
9259 if (candidates
== NULL
)
9262 if (candidates
->next
)
9268 /* If CANDIDATE is invalid due to a bad argument type, return the
9269 pertinent conversion_info.
9271 Otherwise, return NULL. */
9273 static const conversion_info
*
9274 maybe_get_bad_conversion_for_unmatched_call (const z_candidate
*candidate
)
9276 /* Must be an rr_arg_conversion or rr_bad_arg_conversion. */
9277 rejection_reason
*r
= candidate
->reason
;
9287 case rr_arg_conversion
:
9288 return &r
->u
.conversion
;
9290 case rr_bad_arg_conversion
:
9291 return &r
->u
.bad_conversion
;
9295 /* Issue an error and note complaining about a bad argument type at a
9296 callsite with a single candidate FNDECL.
9298 ARG_LOC is the location of the argument (or UNKNOWN_LOCATION, in which
9299 case input_location is used).
9300 FROM_TYPE is the type of the actual argument; TO_TYPE is the type of
9301 the formal parameter. */
9304 complain_about_bad_argument (location_t arg_loc
,
9305 tree from_type
, tree to_type
,
9306 tree fndecl
, int parmnum
)
9308 auto_diagnostic_group d
;
9309 range_label_for_type_mismatch
rhs_label (from_type
, to_type
);
9310 range_label
*label
= &rhs_label
;
9311 if (arg_loc
== UNKNOWN_LOCATION
)
9313 arg_loc
= input_location
;
9316 gcc_rich_location
richloc (arg_loc
, label
);
9318 "cannot convert %qH to %qI",
9319 from_type
, to_type
);
9320 maybe_inform_about_fndecl_for_bogus_argument_init (fndecl
,
9324 /* Subroutine of build_new_method_call_1, for where there are no viable
9325 candidates for the call. */
9328 complain_about_no_candidates_for_method_call (tree instance
,
9329 z_candidate
*candidates
,
9330 tree explicit_targs
,
9332 tree optype
, tree name
,
9333 bool skip_first_for_error
,
9334 vec
<tree
, va_gc
> *user_args
)
9336 auto_diagnostic_group d
;
9337 if (!COMPLETE_OR_OPEN_TYPE_P (basetype
))
9338 cxx_incomplete_type_error (instance
, basetype
);
9340 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
9341 basetype
, optype
, build_tree_list_vec (user_args
),
9342 TREE_TYPE (instance
));
9345 /* Special-case for when there's a single candidate that's failing
9346 due to a bad argument type. */
9347 if (z_candidate
*candidate
= single_z_candidate (candidates
))
9348 if (const conversion_info
*conv
9349 = maybe_get_bad_conversion_for_unmatched_call (candidate
))
9351 complain_about_bad_argument (conv
->loc
,
9352 conv
->from
, conv
->to_type
,
9353 candidate
->fn
, conv
->n_arg
);
9357 tree arglist
= build_tree_list_vec (user_args
);
9358 tree errname
= name
;
9359 bool twiddle
= false;
9360 if (IDENTIFIER_CDTOR_P (errname
))
9362 twiddle
= IDENTIFIER_DTOR_P (errname
);
9363 errname
= constructor_name (basetype
);
9366 errname
= lookup_template_function (errname
, explicit_targs
);
9367 if (skip_first_for_error
)
9368 arglist
= TREE_CHAIN (arglist
);
9369 error ("no matching function for call to %<%T::%s%E(%A)%#V%>",
9370 basetype
, &"~"[!twiddle
], errname
, arglist
,
9371 TREE_TYPE (instance
));
9373 print_z_candidates (location_of (name
), candidates
);
9376 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
9377 be set, upon return, to the function called. ARGS may be NULL.
9378 This may change ARGS. */
9381 build_new_method_call_1 (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9382 tree conversion_path
, int flags
,
9383 tree
*fn_p
, tsubst_flags_t complain
)
9385 struct z_candidate
*candidates
= 0, *cand
;
9386 tree explicit_targs
= NULL_TREE
;
9387 tree basetype
= NULL_TREE
;
9388 tree access_binfo
, binfo
;
9390 tree first_mem_arg
= NULL_TREE
;
9392 bool skip_first_for_error
;
9393 vec
<tree
, va_gc
> *user_args
;
9396 int template_only
= 0;
9400 vec
<tree
, va_gc
> *orig_args
= NULL
;
9403 gcc_assert (instance
!= NULL_TREE
);
9405 /* We don't know what function we're going to call, yet. */
9409 if (error_operand_p (instance
)
9410 || !fns
|| error_operand_p (fns
))
9411 return error_mark_node
;
9413 if (!BASELINK_P (fns
))
9415 if (complain
& tf_error
)
9416 error ("call to non-function %qD", fns
);
9417 return error_mark_node
;
9420 orig_instance
= instance
;
9423 /* Dismantle the baselink to collect all the information we need. */
9424 if (!conversion_path
)
9425 conversion_path
= BASELINK_BINFO (fns
);
9426 access_binfo
= BASELINK_ACCESS_BINFO (fns
);
9427 binfo
= BASELINK_BINFO (fns
);
9428 optype
= BASELINK_OPTYPE (fns
);
9429 fns
= BASELINK_FUNCTIONS (fns
);
9430 if (TREE_CODE (fns
) == TEMPLATE_ID_EXPR
)
9432 explicit_targs
= TREE_OPERAND (fns
, 1);
9433 fns
= TREE_OPERAND (fns
, 0);
9436 gcc_assert (TREE_CODE (fns
) == FUNCTION_DECL
9437 || TREE_CODE (fns
) == TEMPLATE_DECL
9438 || TREE_CODE (fns
) == OVERLOAD
);
9439 fn
= OVL_FIRST (fns
);
9440 name
= DECL_NAME (fn
);
9442 basetype
= TYPE_MAIN_VARIANT (TREE_TYPE (instance
));
9443 gcc_assert (CLASS_TYPE_P (basetype
));
9445 user_args
= args
== NULL
? NULL
: *args
;
9446 /* Under DR 147 A::A() is an invalid constructor call,
9447 not a functional cast. */
9448 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn
))
9450 if (! (complain
& tf_error
))
9451 return error_mark_node
;
9453 basetype
= DECL_CONTEXT (fn
);
9454 name
= constructor_name (basetype
);
9455 auto_diagnostic_group d
;
9456 if (permerror (input_location
,
9457 "cannot call constructor %<%T::%D%> directly",
9459 inform (input_location
, "for a function-style cast, remove the "
9460 "redundant %<::%D%>", name
);
9461 call
= build_functional_cast (basetype
, build_tree_list_vec (user_args
),
9466 if (processing_template_decl
)
9468 orig_args
= args
== NULL
? NULL
: make_tree_vector_copy (*args
);
9469 instance
= build_non_dependent_expr (instance
);
9471 make_args_non_dependent (*args
);
9474 /* Process the argument list. */
9475 if (args
!= NULL
&& *args
!= NULL
)
9477 *args
= resolve_args (*args
, complain
);
9479 return error_mark_node
;
9483 /* Consider the object argument to be used even if we end up selecting a
9484 static member function. */
9485 instance
= mark_type_use (instance
);
9487 /* Figure out whether to skip the first argument for the error
9488 message we will display to users if an error occurs. We don't
9489 want to display any compiler-generated arguments. The "this"
9490 pointer hasn't been added yet. However, we must remove the VTT
9491 pointer if this is a call to a base-class constructor or
9493 skip_first_for_error
= false;
9494 if (IDENTIFIER_CDTOR_P (name
))
9496 /* Callers should explicitly indicate whether they want to ctor
9497 the complete object or just the part without virtual bases. */
9498 gcc_assert (name
!= ctor_identifier
);
9500 /* Remove the VTT pointer, if present. */
9501 if ((name
== base_ctor_identifier
|| name
== base_dtor_identifier
)
9502 && CLASSTYPE_VBASECLASSES (basetype
))
9503 skip_first_for_error
= true;
9505 /* It's OK to call destructors and constructors on cv-qualified
9506 objects. Therefore, convert the INSTANCE to the unqualified
9507 type, if necessary. */
9508 if (!same_type_p (basetype
, TREE_TYPE (instance
)))
9510 instance
= build_this (instance
);
9511 instance
= build_nop (build_pointer_type (basetype
), instance
);
9512 instance
= build_fold_indirect_ref (instance
);
9516 gcc_assert (!DECL_DESTRUCTOR_P (fn
) && !DECL_CONSTRUCTOR_P (fn
));
9518 /* For the overload resolution we need to find the actual `this`
9519 that would be captured if the call turns out to be to a
9520 non-static member function. Do not actually capture it at this
9522 if (DECL_CONSTRUCTOR_P (fn
))
9523 /* Constructors don't use the enclosing 'this'. */
9524 first_mem_arg
= instance
;
9526 first_mem_arg
= maybe_resolve_dummy (instance
, false);
9528 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9529 p
= conversion_obstack_alloc (0);
9531 /* The number of arguments artificial parms in ARGS; we subtract one because
9532 there's no 'this' in ARGS. */
9533 unsigned skip
= num_artificial_parms_for (fn
) - 1;
9535 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
9536 initializer, not T({ }). */
9537 if (DECL_CONSTRUCTOR_P (fn
)
9538 && vec_safe_length (user_args
) > skip
9539 && DIRECT_LIST_INIT_P ((*user_args
)[skip
]))
9541 tree init_list
= (*user_args
)[skip
];
9542 tree init
= NULL_TREE
;
9544 gcc_assert (user_args
->length () == skip
+ 1
9545 && !(flags
& LOOKUP_ONLYCONVERTING
));
9547 /* If the initializer list has no elements and T is a class type with
9548 a default constructor, the object is value-initialized. Handle
9549 this here so we don't need to handle it wherever we use
9550 build_special_member_call. */
9551 if (CONSTRUCTOR_NELTS (init_list
) == 0
9552 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype
)
9553 /* For a user-provided default constructor, use the normal
9554 mechanisms so that protected access works. */
9555 && type_has_non_user_provided_default_constructor (basetype
)
9556 && !processing_template_decl
)
9557 init
= build_value_init (basetype
, complain
);
9559 /* If BASETYPE is an aggregate, we need to do aggregate
9561 else if (CP_AGGREGATE_TYPE_P (basetype
))
9563 init
= reshape_init (basetype
, init_list
, complain
);
9564 init
= digest_init (basetype
, init
, complain
);
9569 if (is_dummy_object (instance
))
9570 return get_target_expr_sfinae (init
, complain
);
9571 init
= build2 (INIT_EXPR
, TREE_TYPE (instance
), instance
, init
);
9572 TREE_SIDE_EFFECTS (init
) = true;
9576 /* Otherwise go ahead with overload resolution. */
9577 add_list_candidates (fns
, first_mem_arg
, user_args
,
9578 basetype
, explicit_targs
, template_only
,
9579 conversion_path
, access_binfo
, flags
,
9580 &candidates
, complain
);
9583 add_candidates (fns
, first_mem_arg
, user_args
, optype
,
9584 explicit_targs
, template_only
, conversion_path
,
9585 access_binfo
, flags
, &candidates
, complain
);
9587 any_viable_p
= false;
9588 candidates
= splice_viable (candidates
, false, &any_viable_p
);
9592 if (complain
& tf_error
)
9593 complain_about_no_candidates_for_method_call (instance
, candidates
,
9594 explicit_targs
, basetype
,
9596 skip_first_for_error
,
9598 call
= error_mark_node
;
9602 cand
= tourney (candidates
, complain
);
9609 if (complain
& tf_error
)
9611 pretty_name
= name_as_c_string (name
, basetype
, &free_p
);
9612 arglist
= build_tree_list_vec (user_args
);
9613 if (skip_first_for_error
)
9614 arglist
= TREE_CHAIN (arglist
);
9615 auto_diagnostic_group d
;
9616 if (!any_strictly_viable (candidates
))
9617 error ("no matching function for call to %<%s(%A)%>",
9618 pretty_name
, arglist
);
9620 error ("call of overloaded %<%s(%A)%> is ambiguous",
9621 pretty_name
, arglist
);
9622 print_z_candidates (location_of (name
), candidates
);
9626 call
= error_mark_node
;
9633 if (!(flags
& LOOKUP_NONVIRTUAL
)
9634 && DECL_PURE_VIRTUAL_P (fn
)
9635 && instance
== current_class_ref
9636 && (complain
& tf_warning
))
9638 /* This is not an error, it is runtime undefined
9640 if (!current_function_decl
)
9641 warning (0, "pure virtual %q#D called from "
9642 "non-static data member initializer", fn
);
9643 else if (DECL_CONSTRUCTOR_P (current_function_decl
)
9644 || DECL_DESTRUCTOR_P (current_function_decl
))
9645 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl
)
9646 ? G_("pure virtual %q#D called from constructor")
9647 : G_("pure virtual %q#D called from destructor")),
9651 if (TREE_CODE (TREE_TYPE (fn
)) == METHOD_TYPE
9652 && !DECL_CONSTRUCTOR_P (fn
)
9653 && is_dummy_object (instance
))
9655 instance
= maybe_resolve_dummy (instance
, true);
9656 if (instance
== error_mark_node
)
9657 call
= error_mark_node
;
9658 else if (!is_dummy_object (instance
))
9660 /* We captured 'this' in the current lambda now that
9661 we know we really need it. */
9662 cand
->first_arg
= instance
;
9664 else if (any_dependent_bases_p ())
9665 /* We can't tell until instantiation time whether we can use
9666 *this as the implicit object argument. */;
9669 if (complain
& tf_error
)
9670 error ("cannot call member function %qD without object",
9672 call
= error_mark_node
;
9676 if (call
!= error_mark_node
)
9678 /* Optimize away vtable lookup if we know that this
9679 function can't be overridden. We need to check if
9680 the context and the type where we found fn are the same,
9681 actually FN might be defined in a different class
9682 type because of a using-declaration. In this case, we
9683 do not want to perform a non-virtual call. */
9684 if (DECL_VINDEX (fn
) && ! (flags
& LOOKUP_NONVIRTUAL
)
9685 && same_type_ignoring_top_level_qualifiers_p
9686 (DECL_CONTEXT (fn
), BINFO_TYPE (binfo
))
9687 && resolves_to_fixed_type_p (instance
, 0))
9688 flags
|= LOOKUP_NONVIRTUAL
;
9690 flags
|= LOOKUP_EXPLICIT_TMPL_ARGS
;
9691 /* Now we know what function is being called. */
9694 /* Build the actual CALL_EXPR. */
9695 call
= build_over_call (cand
, flags
, complain
);
9696 /* In an expression of the form `a->f()' where `f' turns
9697 out to be a static member function, `a' is
9698 none-the-less evaluated. */
9699 if (TREE_CODE (TREE_TYPE (fn
)) != METHOD_TYPE
9700 && !is_dummy_object (instance
)
9701 && TREE_SIDE_EFFECTS (instance
))
9703 /* But avoid the implicit lvalue-rvalue conversion when 'a'
9706 if (TREE_THIS_VOLATILE (a
))
9708 call
= build2 (COMPOUND_EXPR
, TREE_TYPE (call
), a
, call
);
9710 else if (call
!= error_mark_node
9711 && DECL_DESTRUCTOR_P (cand
->fn
)
9712 && !VOID_TYPE_P (TREE_TYPE (call
)))
9713 /* An explicit call of the form "x->~X()" has type
9714 "void". However, on platforms where destructors
9715 return "this" (i.e., those where
9716 targetm.cxx.cdtor_returns_this is true), such calls
9717 will appear to have a return value of pointer type
9718 to the low-level call machinery. We do not want to
9719 change the low-level machinery, since we want to be
9720 able to optimize "delete f()" on such platforms as
9721 "operator delete(~X(f()))" (rather than generating
9722 "t = f(), ~X(t), operator delete (t)"). */
9723 call
= build_nop (void_type_node
, call
);
9728 if (processing_template_decl
&& call
!= error_mark_node
)
9730 bool cast_to_void
= false;
9732 if (TREE_CODE (call
) == COMPOUND_EXPR
)
9733 call
= TREE_OPERAND (call
, 1);
9734 else if (TREE_CODE (call
) == NOP_EXPR
)
9736 cast_to_void
= true;
9737 call
= TREE_OPERAND (call
, 0);
9739 if (INDIRECT_REF_P (call
))
9740 call
= TREE_OPERAND (call
, 0);
9741 call
= (build_min_non_dep_call_vec
9743 build_min (COMPONENT_REF
, TREE_TYPE (CALL_EXPR_FN (call
)),
9744 orig_instance
, orig_fns
, NULL_TREE
),
9746 SET_EXPR_LOCATION (call
, input_location
);
9747 call
= convert_from_reference (call
);
9749 call
= build_nop (void_type_node
, call
);
9752 /* Free all the conversions we allocated. */
9753 obstack_free (&conversion_obstack
, p
);
9755 if (orig_args
!= NULL
)
9756 release_tree_vector (orig_args
);
9761 /* Wrapper for above. */
9764 build_new_method_call (tree instance
, tree fns
, vec
<tree
, va_gc
> **args
,
9765 tree conversion_path
, int flags
,
9766 tree
*fn_p
, tsubst_flags_t complain
)
9769 bool subtime
= timevar_cond_start (TV_OVERLOAD
);
9770 ret
= build_new_method_call_1 (instance
, fns
, args
, conversion_path
, flags
,
9772 timevar_cond_stop (TV_OVERLOAD
, subtime
);
9776 /* Returns true iff standard conversion sequence ICS1 is a proper
9777 subsequence of ICS2. */
9780 is_subseq (conversion
*ics1
, conversion
*ics2
)
9782 /* We can assume that a conversion of the same code
9783 between the same types indicates a subsequence since we only get
9784 here if the types we are converting from are the same. */
9786 while (ics1
->kind
== ck_rvalue
9787 || ics1
->kind
== ck_lvalue
)
9788 ics1
= next_conversion (ics1
);
9792 while (ics2
->kind
== ck_rvalue
9793 || ics2
->kind
== ck_lvalue
)
9794 ics2
= next_conversion (ics2
);
9796 if (ics2
->kind
== ck_user
9797 || ics2
->kind
== ck_ambig
9798 || ics2
->kind
== ck_aggr
9799 || ics2
->kind
== ck_list
9800 || ics2
->kind
== ck_identity
)
9801 /* At this point, ICS1 cannot be a proper subsequence of
9802 ICS2. We can get a USER_CONV when we are comparing the
9803 second standard conversion sequence of two user conversion
9807 ics2
= next_conversion (ics2
);
9809 while (ics2
->kind
== ck_rvalue
9810 || ics2
->kind
== ck_lvalue
)
9811 ics2
= next_conversion (ics2
);
9813 if (ics2
->kind
== ics1
->kind
9814 && same_type_p (ics2
->type
, ics1
->type
)
9815 && (ics1
->kind
== ck_identity
9816 || same_type_p (next_conversion (ics2
)->type
,
9817 next_conversion (ics1
)->type
)))
9822 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
9823 be any _TYPE nodes. */
9826 is_properly_derived_from (tree derived
, tree base
)
9828 if (!CLASS_TYPE_P (derived
) || !CLASS_TYPE_P (base
))
9831 /* We only allow proper derivation here. The DERIVED_FROM_P macro
9832 considers every class derived from itself. */
9833 return (!same_type_ignoring_top_level_qualifiers_p (derived
, base
)
9834 && DERIVED_FROM_P (base
, derived
));
9837 /* We build the ICS for an implicit object parameter as a pointer
9838 conversion sequence. However, such a sequence should be compared
9839 as if it were a reference conversion sequence. If ICS is the
9840 implicit conversion sequence for an implicit object parameter,
9841 modify it accordingly. */
9844 maybe_handle_implicit_object (conversion
**ics
)
9848 /* [over.match.funcs]
9850 For non-static member functions, the type of the
9851 implicit object parameter is "reference to cv X"
9852 where X is the class of which the function is a
9853 member and cv is the cv-qualification on the member
9854 function declaration. */
9855 conversion
*t
= *ics
;
9856 tree reference_type
;
9858 /* The `this' parameter is a pointer to a class type. Make the
9859 implicit conversion talk about a reference to that same class
9861 reference_type
= TREE_TYPE (t
->type
);
9862 reference_type
= build_reference_type (reference_type
);
9864 if (t
->kind
== ck_qual
)
9865 t
= next_conversion (t
);
9866 if (t
->kind
== ck_ptr
)
9867 t
= next_conversion (t
);
9868 t
= build_identity_conv (TREE_TYPE (t
->type
), NULL_TREE
);
9869 t
= direct_reference_binding (reference_type
, t
);
9871 t
->rvaluedness_matches_p
= 0;
9876 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
9877 and return the initial reference binding conversion. Otherwise,
9878 leave *ICS unchanged and return NULL. */
9881 maybe_handle_ref_bind (conversion
**ics
)
9883 if ((*ics
)->kind
== ck_ref_bind
)
9885 conversion
*old_ics
= *ics
;
9886 *ics
= next_conversion (old_ics
);
9887 (*ics
)->user_conv_p
= old_ics
->user_conv_p
;
9894 /* Compare two implicit conversion sequences according to the rules set out in
9895 [over.ics.rank]. Return values:
9897 1: ics1 is better than ics2
9898 -1: ics2 is better than ics1
9899 0: ics1 and ics2 are indistinguishable */
9902 compare_ics (conversion
*ics1
, conversion
*ics2
)
9908 tree deref_from_type1
= NULL_TREE
;
9909 tree deref_from_type2
= NULL_TREE
;
9910 tree deref_to_type1
= NULL_TREE
;
9911 tree deref_to_type2
= NULL_TREE
;
9912 conversion_rank rank1
, rank2
;
9914 /* REF_BINDING is nonzero if the result of the conversion sequence
9915 is a reference type. In that case REF_CONV is the reference
9916 binding conversion. */
9917 conversion
*ref_conv1
;
9918 conversion
*ref_conv2
;
9920 /* Compare badness before stripping the reference conversion. */
9921 if (ics1
->bad_p
> ics2
->bad_p
)
9923 else if (ics1
->bad_p
< ics2
->bad_p
)
9926 /* Handle implicit object parameters. */
9927 maybe_handle_implicit_object (&ics1
);
9928 maybe_handle_implicit_object (&ics2
);
9930 /* Handle reference parameters. */
9931 ref_conv1
= maybe_handle_ref_bind (&ics1
);
9932 ref_conv2
= maybe_handle_ref_bind (&ics2
);
9934 /* List-initialization sequence L1 is a better conversion sequence than
9935 list-initialization sequence L2 if L1 converts to
9936 std::initializer_list<X> for some X and L2 does not. */
9937 if (ics1
->kind
== ck_list
&& ics2
->kind
!= ck_list
)
9939 if (ics2
->kind
== ck_list
&& ics1
->kind
!= ck_list
)
9944 When comparing the basic forms of implicit conversion sequences (as
9945 defined in _over.best.ics_)
9947 --a standard conversion sequence (_over.ics.scs_) is a better
9948 conversion sequence than a user-defined conversion sequence
9949 or an ellipsis conversion sequence, and
9951 --a user-defined conversion sequence (_over.ics.user_) is a
9952 better conversion sequence than an ellipsis conversion sequence
9953 (_over.ics.ellipsis_). */
9954 /* Use BAD_CONVERSION_RANK because we already checked for a badness
9955 mismatch. If both ICS are bad, we try to make a decision based on
9956 what would have happened if they'd been good. This is not an
9957 extension, we'll still give an error when we build up the call; this
9958 just helps us give a more helpful error message. */
9959 rank1
= BAD_CONVERSION_RANK (ics1
);
9960 rank2
= BAD_CONVERSION_RANK (ics2
);
9964 else if (rank1
< rank2
)
9967 if (ics1
->ellipsis_p
)
9968 /* Both conversions are ellipsis conversions. */
9971 /* User-defined conversion sequence U1 is a better conversion sequence
9972 than another user-defined conversion sequence U2 if they contain the
9973 same user-defined conversion operator or constructor and if the sec-
9974 ond standard conversion sequence of U1 is better than the second
9975 standard conversion sequence of U2. */
9977 /* Handle list-conversion with the same code even though it isn't always
9978 ranked as a user-defined conversion and it doesn't have a second
9979 standard conversion sequence; it will still have the desired effect.
9980 Specifically, we need to do the reference binding comparison at the
9981 end of this function. */
9983 if (ics1
->user_conv_p
|| ics1
->kind
== ck_list
|| ics1
->kind
== ck_aggr
)
9988 for (t1
= ics1
; t1
->kind
!= ck_user
; t1
= next_conversion (t1
))
9989 if (t1
->kind
== ck_ambig
|| t1
->kind
== ck_aggr
9990 || t1
->kind
== ck_list
)
9992 for (t2
= ics2
; t2
->kind
!= ck_user
; t2
= next_conversion (t2
))
9993 if (t2
->kind
== ck_ambig
|| t2
->kind
== ck_aggr
9994 || t2
->kind
== ck_list
)
9997 if (t1
->kind
!= t2
->kind
)
9999 else if (t1
->kind
== ck_user
)
10001 tree f1
= t1
->cand
? t1
->cand
->fn
: t1
->type
;
10002 tree f2
= t2
->cand
? t2
->cand
->fn
: t2
->type
;
10008 /* For ambiguous or aggregate conversions, use the target type as
10009 a proxy for the conversion function. */
10010 if (!same_type_ignoring_top_level_qualifiers_p (t1
->type
, t2
->type
))
10014 /* We can just fall through here, after setting up
10015 FROM_TYPE1 and FROM_TYPE2. */
10016 from_type1
= t1
->type
;
10017 from_type2
= t2
->type
;
10024 /* We're dealing with two standard conversion sequences.
10028 Standard conversion sequence S1 is a better conversion
10029 sequence than standard conversion sequence S2 if
10031 --S1 is a proper subsequence of S2 (comparing the conversion
10032 sequences in the canonical form defined by _over.ics.scs_,
10033 excluding any Lvalue Transformation; the identity
10034 conversion sequence is considered to be a subsequence of
10035 any non-identity conversion sequence */
10038 while (t1
->kind
!= ck_identity
)
10039 t1
= next_conversion (t1
);
10040 from_type1
= t1
->type
;
10043 while (t2
->kind
!= ck_identity
)
10044 t2
= next_conversion (t2
);
10045 from_type2
= t2
->type
;
10048 /* One sequence can only be a subsequence of the other if they start with
10049 the same type. They can start with different types when comparing the
10050 second standard conversion sequence in two user-defined conversion
10052 if (same_type_p (from_type1
, from_type2
))
10054 if (is_subseq (ics1
, ics2
))
10056 if (is_subseq (ics2
, ics1
))
10064 --the rank of S1 is better than the rank of S2 (by the rules
10067 Standard conversion sequences are ordered by their ranks: an Exact
10068 Match is a better conversion than a Promotion, which is a better
10069 conversion than a Conversion.
10071 Two conversion sequences with the same rank are indistinguishable
10072 unless one of the following rules applies:
10074 --A conversion that does not a convert a pointer, pointer to member,
10075 or std::nullptr_t to bool is better than one that does.
10077 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
10078 so that we do not have to check it explicitly. */
10079 if (ics1
->rank
< ics2
->rank
)
10081 else if (ics2
->rank
< ics1
->rank
)
10084 to_type1
= ics1
->type
;
10085 to_type2
= ics2
->type
;
10087 /* A conversion from scalar arithmetic type to complex is worse than a
10088 conversion between scalar arithmetic types. */
10089 if (same_type_p (from_type1
, from_type2
)
10090 && ARITHMETIC_TYPE_P (from_type1
)
10091 && ARITHMETIC_TYPE_P (to_type1
)
10092 && ARITHMETIC_TYPE_P (to_type2
)
10093 && ((TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10094 != (TREE_CODE (to_type2
) == COMPLEX_TYPE
)))
10096 if (TREE_CODE (to_type1
) == COMPLEX_TYPE
)
10102 if (TYPE_PTR_P (from_type1
)
10103 && TYPE_PTR_P (from_type2
)
10104 && TYPE_PTR_P (to_type1
)
10105 && TYPE_PTR_P (to_type2
))
10107 deref_from_type1
= TREE_TYPE (from_type1
);
10108 deref_from_type2
= TREE_TYPE (from_type2
);
10109 deref_to_type1
= TREE_TYPE (to_type1
);
10110 deref_to_type2
= TREE_TYPE (to_type2
);
10112 /* The rules for pointers to members A::* are just like the rules
10113 for pointers A*, except opposite: if B is derived from A then
10114 A::* converts to B::*, not vice versa. For that reason, we
10115 switch the from_ and to_ variables here. */
10116 else if ((TYPE_PTRDATAMEM_P (from_type1
) && TYPE_PTRDATAMEM_P (from_type2
)
10117 && TYPE_PTRDATAMEM_P (to_type1
) && TYPE_PTRDATAMEM_P (to_type2
))
10118 || (TYPE_PTRMEMFUNC_P (from_type1
)
10119 && TYPE_PTRMEMFUNC_P (from_type2
)
10120 && TYPE_PTRMEMFUNC_P (to_type1
)
10121 && TYPE_PTRMEMFUNC_P (to_type2
)))
10123 deref_to_type1
= TYPE_PTRMEM_CLASS_TYPE (from_type1
);
10124 deref_to_type2
= TYPE_PTRMEM_CLASS_TYPE (from_type2
);
10125 deref_from_type1
= TYPE_PTRMEM_CLASS_TYPE (to_type1
);
10126 deref_from_type2
= TYPE_PTRMEM_CLASS_TYPE (to_type2
);
10129 if (deref_from_type1
!= NULL_TREE
10130 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1
))
10131 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2
)))
10133 /* This was one of the pointer or pointer-like conversions.
10137 --If class B is derived directly or indirectly from class A,
10138 conversion of B* to A* is better than conversion of B* to
10139 void*, and conversion of A* to void* is better than
10140 conversion of B* to void*. */
10141 if (VOID_TYPE_P (deref_to_type1
)
10142 && VOID_TYPE_P (deref_to_type2
))
10144 if (is_properly_derived_from (deref_from_type1
,
10147 else if (is_properly_derived_from (deref_from_type2
,
10151 else if (VOID_TYPE_P (deref_to_type1
)
10152 || VOID_TYPE_P (deref_to_type2
))
10154 if (same_type_p (deref_from_type1
, deref_from_type2
))
10156 if (VOID_TYPE_P (deref_to_type2
))
10158 if (is_properly_derived_from (deref_from_type1
,
10162 /* We know that DEREF_TO_TYPE1 is `void' here. */
10163 else if (is_properly_derived_from (deref_from_type1
,
10168 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1
))
10169 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2
)))
10173 --If class B is derived directly or indirectly from class A
10174 and class C is derived directly or indirectly from B,
10176 --conversion of C* to B* is better than conversion of C* to
10179 --conversion of B* to A* is better than conversion of C* to
10181 if (same_type_p (deref_from_type1
, deref_from_type2
))
10183 if (is_properly_derived_from (deref_to_type1
,
10186 else if (is_properly_derived_from (deref_to_type2
,
10190 else if (same_type_p (deref_to_type1
, deref_to_type2
))
10192 if (is_properly_derived_from (deref_from_type2
,
10195 else if (is_properly_derived_from (deref_from_type1
,
10201 else if (CLASS_TYPE_P (non_reference (from_type1
))
10202 && same_type_p (from_type1
, from_type2
))
10204 tree from
= non_reference (from_type1
);
10208 --binding of an expression of type C to a reference of type
10209 B& is better than binding an expression of type C to a
10210 reference of type A&
10212 --conversion of C to B is better than conversion of C to A, */
10213 if (is_properly_derived_from (from
, to_type1
)
10214 && is_properly_derived_from (from
, to_type2
))
10216 if (is_properly_derived_from (to_type1
, to_type2
))
10218 else if (is_properly_derived_from (to_type2
, to_type1
))
10222 else if (CLASS_TYPE_P (non_reference (to_type1
))
10223 && same_type_p (to_type1
, to_type2
))
10225 tree to
= non_reference (to_type1
);
10229 --binding of an expression of type B to a reference of type
10230 A& is better than binding an expression of type C to a
10231 reference of type A&,
10233 --conversion of B to A is better than conversion of C to A */
10234 if (is_properly_derived_from (from_type1
, to
)
10235 && is_properly_derived_from (from_type2
, to
))
10237 if (is_properly_derived_from (from_type2
, from_type1
))
10239 else if (is_properly_derived_from (from_type1
, from_type2
))
10246 --S1 and S2 differ only in their qualification conversion and yield
10247 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
10248 qualification signature of type T1 is a proper subset of the cv-
10249 qualification signature of type T2 */
10250 if (ics1
->kind
== ck_qual
10251 && ics2
->kind
== ck_qual
10252 && same_type_p (from_type1
, from_type2
))
10254 int result
= comp_cv_qual_signature (to_type1
, to_type2
);
10261 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
10262 to an implicit object parameter of a non-static member function
10263 declared without a ref-qualifier, and either S1 binds an lvalue
10264 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
10265 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
10266 draft standard, 13.3.3.2)
10268 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
10269 types to which the references refer are the same type except for
10270 top-level cv-qualifiers, and the type to which the reference
10271 initialized by S2 refers is more cv-qualified than the type to
10272 which the reference initialized by S1 refers.
10274 DR 1328 [over.match.best]: the context is an initialization by
10275 conversion function for direct reference binding (13.3.1.6) of a
10276 reference to function type, the return type of F1 is the same kind of
10277 reference (i.e. lvalue or rvalue) as the reference being initialized,
10278 and the return type of F2 is not. */
10280 if (ref_conv1
&& ref_conv2
)
10282 if (!ref_conv1
->this_p
&& !ref_conv2
->this_p
10283 && (ref_conv1
->rvaluedness_matches_p
10284 != ref_conv2
->rvaluedness_matches_p
)
10285 && (same_type_p (ref_conv1
->type
, ref_conv2
->type
)
10286 || (TYPE_REF_IS_RVALUE (ref_conv1
->type
)
10287 != TYPE_REF_IS_RVALUE (ref_conv2
->type
))))
10289 if (ref_conv1
->bad_p
10290 && !same_type_p (TREE_TYPE (ref_conv1
->type
),
10291 TREE_TYPE (ref_conv2
->type
)))
10292 /* Don't prefer a bad conversion that drops cv-quals to a bad
10293 conversion with the wrong rvalueness. */
10295 return (ref_conv1
->rvaluedness_matches_p
10296 - ref_conv2
->rvaluedness_matches_p
);
10299 if (same_type_ignoring_top_level_qualifiers_p (to_type1
, to_type2
))
10301 int q1
= cp_type_quals (TREE_TYPE (ref_conv1
->type
));
10302 int q2
= cp_type_quals (TREE_TYPE (ref_conv2
->type
));
10303 if (ref_conv1
->bad_p
)
10305 /* Prefer the one that drops fewer cv-quals. */
10306 tree ftype
= next_conversion (ref_conv1
)->type
;
10307 int fquals
= cp_type_quals (ftype
);
10311 return comp_cv_qualification (q2
, q1
);
10315 /* Neither conversion sequence is better than the other. */
10319 /* The source type for this standard conversion sequence. */
10322 source_type (conversion
*t
)
10324 for (;; t
= next_conversion (t
))
10326 if (t
->kind
== ck_user
10327 || t
->kind
== ck_ambig
10328 || t
->kind
== ck_identity
)
10331 gcc_unreachable ();
10334 /* Note a warning about preferring WINNER to LOSER. We do this by storing
10335 a pointer to LOSER and re-running joust to produce the warning if WINNER
10336 is actually used. */
10339 add_warning (struct z_candidate
*winner
, struct z_candidate
*loser
)
10341 candidate_warning
*cw
= (candidate_warning
*)
10342 conversion_obstack_alloc (sizeof (candidate_warning
));
10344 cw
->next
= winner
->warnings
;
10345 winner
->warnings
= cw
;
10348 /* Compare two candidates for overloading as described in
10349 [over.match.best]. Return values:
10351 1: cand1 is better than cand2
10352 -1: cand2 is better than cand1
10353 0: cand1 and cand2 are indistinguishable */
10356 joust (struct z_candidate
*cand1
, struct z_candidate
*cand2
, bool warn
,
10357 tsubst_flags_t complain
)
10360 int off1
= 0, off2
= 0;
10364 /* Candidates that involve bad conversions are always worse than those
10366 if (cand1
->viable
> cand2
->viable
)
10368 if (cand1
->viable
< cand2
->viable
)
10371 /* If we have two pseudo-candidates for conversions to the same type,
10372 or two candidates for the same function, arbitrarily pick one. */
10373 if (cand1
->fn
== cand2
->fn
10374 && (IS_TYPE_OR_DECL_P (cand1
->fn
)))
10377 /* Prefer a non-deleted function over an implicitly deleted move
10378 constructor or assignment operator. This differs slightly from the
10379 wording for issue 1402 (which says the move op is ignored by overload
10380 resolution), but this way produces better error messages. */
10381 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10382 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10383 && DECL_DELETED_FN (cand1
->fn
) != DECL_DELETED_FN (cand2
->fn
))
10385 if (DECL_DELETED_FN (cand1
->fn
) && DECL_DEFAULTED_FN (cand1
->fn
)
10386 && move_fn_p (cand1
->fn
))
10388 if (DECL_DELETED_FN (cand2
->fn
) && DECL_DEFAULTED_FN (cand2
->fn
)
10389 && move_fn_p (cand2
->fn
))
10393 /* a viable function F1
10394 is defined to be a better function than another viable function F2 if
10395 for all arguments i, ICSi(F1) is not a worse conversion sequence than
10396 ICSi(F2), and then */
10398 /* for some argument j, ICSj(F1) is a better conversion sequence than
10401 /* For comparing static and non-static member functions, we ignore
10402 the implicit object parameter of the non-static function. The
10403 standard says to pretend that the static function has an object
10404 parm, but that won't work with operator overloading. */
10405 len
= cand1
->num_convs
;
10406 if (len
!= cand2
->num_convs
)
10408 int static_1
= DECL_STATIC_FUNCTION_P (cand1
->fn
);
10409 int static_2
= DECL_STATIC_FUNCTION_P (cand2
->fn
);
10411 if (DECL_CONSTRUCTOR_P (cand1
->fn
)
10412 && is_list_ctor (cand1
->fn
) != is_list_ctor (cand2
->fn
))
10413 /* We're comparing a near-match list constructor and a near-match
10414 non-list constructor. Just treat them as unordered. */
10417 gcc_assert (static_1
!= static_2
);
10428 for (i
= 0; i
< len
; ++i
)
10430 conversion
*t1
= cand1
->convs
[i
+ off1
];
10431 conversion
*t2
= cand2
->convs
[i
+ off2
];
10432 int comp
= compare_ics (t1
, t2
);
10436 if ((complain
& tf_warning
)
10438 && (CONVERSION_RANK (t1
) + CONVERSION_RANK (t2
)
10439 == cr_std
+ cr_promotion
)
10440 && t1
->kind
== ck_std
10441 && t2
->kind
== ck_std
10442 && TREE_CODE (t1
->type
) == INTEGER_TYPE
10443 && TREE_CODE (t2
->type
) == INTEGER_TYPE
10444 && (TYPE_PRECISION (t1
->type
)
10445 == TYPE_PRECISION (t2
->type
))
10446 && (TYPE_UNSIGNED (next_conversion (t1
)->type
)
10447 || (TREE_CODE (next_conversion (t1
)->type
)
10448 == ENUMERAL_TYPE
)))
10450 tree type
= next_conversion (t1
)->type
;
10452 struct z_candidate
*w
, *l
;
10454 type1
= t1
->type
, type2
= t2
->type
,
10455 w
= cand1
, l
= cand2
;
10457 type1
= t2
->type
, type2
= t1
->type
,
10458 w
= cand2
, l
= cand1
;
10462 warning (OPT_Wsign_promo
, "passing %qT chooses %qT over %qT",
10463 type
, type1
, type2
);
10464 warning (OPT_Wsign_promo
, " in call to %qD", w
->fn
);
10467 add_warning (w
, l
);
10470 if (winner
&& comp
!= winner
)
10479 /* warn about confusing overload resolution for user-defined conversions,
10480 either between a constructor and a conversion op, or between two
10482 if ((complain
& tf_warning
)
10483 && winner
&& warn_conversion
&& cand1
->second_conv
10484 && (!DECL_CONSTRUCTOR_P (cand1
->fn
) || !DECL_CONSTRUCTOR_P (cand2
->fn
))
10485 && winner
!= compare_ics (cand1
->second_conv
, cand2
->second_conv
))
10487 struct z_candidate
*w
, *l
;
10488 bool give_warning
= false;
10491 w
= cand1
, l
= cand2
;
10493 w
= cand2
, l
= cand1
;
10495 /* We don't want to complain about `X::operator T1 ()'
10496 beating `X::operator T2 () const', when T2 is a no less
10497 cv-qualified version of T1. */
10498 if (DECL_CONTEXT (w
->fn
) == DECL_CONTEXT (l
->fn
)
10499 && !DECL_CONSTRUCTOR_P (w
->fn
) && !DECL_CONSTRUCTOR_P (l
->fn
))
10501 tree t
= TREE_TYPE (TREE_TYPE (l
->fn
));
10502 tree f
= TREE_TYPE (TREE_TYPE (w
->fn
));
10504 if (TREE_CODE (t
) == TREE_CODE (f
) && INDIRECT_TYPE_P (t
))
10509 if (!comp_ptr_ttypes (t
, f
))
10510 give_warning
= true;
10513 give_warning
= true;
10519 tree source
= source_type (w
->convs
[0]);
10520 if (INDIRECT_TYPE_P (source
))
10521 source
= TREE_TYPE (source
);
10522 auto_diagnostic_group d
;
10523 if (warning (OPT_Wconversion
, "choosing %qD over %qD", w
->fn
, l
->fn
)
10524 && warning (OPT_Wconversion
, " for conversion from %qH to %qI",
10525 source
, w
->second_conv
->type
))
10527 inform (input_location
, " because conversion sequence for the argument is better");
10531 add_warning (w
, l
);
10537 /* DR 495 moved this tiebreaker above the template ones. */
10538 /* or, if not that,
10539 the context is an initialization by user-defined conversion (see
10540 _dcl.init_ and _over.match.user_) and the standard conversion
10541 sequence from the return type of F1 to the destination type (i.e.,
10542 the type of the entity being initialized) is a better conversion
10543 sequence than the standard conversion sequence from the return type
10544 of F2 to the destination type. */
10546 if (cand1
->second_conv
)
10548 winner
= compare_ics (cand1
->second_conv
, cand2
->second_conv
);
10553 /* or, if not that,
10554 F1 is a non-template function and F2 is a template function
10557 if (!cand1
->template_decl
&& cand2
->template_decl
)
10559 else if (cand1
->template_decl
&& !cand2
->template_decl
)
10562 /* or, if not that,
10563 F1 and F2 are template functions and the function template for F1 is
10564 more specialized than the template for F2 according to the partial
10567 if (cand1
->template_decl
&& cand2
->template_decl
)
10569 winner
= more_specialized_fn
10570 (TI_TEMPLATE (cand1
->template_decl
),
10571 TI_TEMPLATE (cand2
->template_decl
),
10572 /* [temp.func.order]: The presence of unused ellipsis and default
10573 arguments has no effect on the partial ordering of function
10574 templates. add_function_candidate() will not have
10575 counted the "this" argument for constructors. */
10576 cand1
->num_convs
+ DECL_CONSTRUCTOR_P (cand1
->fn
));
10582 // or, if not that, F1 is more constrained than F2.
10583 if (flag_concepts
&& DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
))
10585 winner
= more_constrained (cand1
->fn
, cand2
->fn
);
10590 /* F1 is generated from a deduction-guide (13.3.1.8) and F2 is not */
10591 if (deduction_guide_p (cand1
->fn
))
10593 gcc_assert (deduction_guide_p (cand2
->fn
));
10594 /* We distinguish between candidates from an explicit deduction guide and
10595 candidates built from a constructor based on DECL_ARTIFICIAL. */
10596 int art1
= DECL_ARTIFICIAL (cand1
->fn
);
10597 int art2
= DECL_ARTIFICIAL (cand2
->fn
);
10599 return art2
- art1
;
10603 /* Prefer the special copy guide over a declared copy/move
10605 if (copy_guide_p (cand1
->fn
))
10607 if (copy_guide_p (cand2
->fn
))
10610 /* Prefer a candidate generated from a non-template constructor. */
10611 int tg1
= template_guide_p (cand1
->fn
);
10612 int tg2
= template_guide_p (cand2
->fn
);
10618 /* F1 is a member of a class D, F2 is a member of a base class B of D, and
10619 for all arguments the corresponding parameters of F1 and F2 have the same
10620 type (CWG 2273/2277). */
10621 if (DECL_P (cand1
->fn
) && DECL_CLASS_SCOPE_P (cand1
->fn
)
10622 && !DECL_CONV_FN_P (cand1
->fn
)
10623 && DECL_P (cand2
->fn
) && DECL_CLASS_SCOPE_P (cand2
->fn
)
10624 && !DECL_CONV_FN_P (cand2
->fn
))
10626 tree base1
= DECL_CONTEXT (strip_inheriting_ctors (cand1
->fn
));
10627 tree base2
= DECL_CONTEXT (strip_inheriting_ctors (cand2
->fn
));
10629 bool used1
= false;
10630 bool used2
= false;
10631 if (base1
== base2
)
10632 /* No difference. */;
10633 else if (DERIVED_FROM_P (base1
, base2
))
10635 else if (DERIVED_FROM_P (base2
, base1
))
10638 if (int diff
= used2
- used1
)
10640 for (i
= 0; i
< len
; ++i
)
10642 conversion
*t1
= cand1
->convs
[i
+ off1
];
10643 conversion
*t2
= cand2
->convs
[i
+ off2
];
10644 if (!same_type_p (t1
->type
, t2
->type
))
10652 /* Check whether we can discard a builtin candidate, either because we
10653 have two identical ones or matching builtin and non-builtin candidates.
10655 (Pedantically in the latter case the builtin which matched the user
10656 function should not be added to the overload set, but we spot it here.
10659 ... the builtin candidates include ...
10660 - do not have the same parameter type list as any non-template
10661 non-member candidate. */
10663 if (identifier_p (cand1
->fn
) || identifier_p (cand2
->fn
))
10665 for (i
= 0; i
< len
; ++i
)
10666 if (!same_type_p (cand1
->convs
[i
]->type
,
10667 cand2
->convs
[i
]->type
))
10669 if (i
== cand1
->num_convs
)
10671 if (cand1
->fn
== cand2
->fn
)
10672 /* Two built-in candidates; arbitrarily pick one. */
10674 else if (identifier_p (cand1
->fn
))
10675 /* cand1 is built-in; prefer cand2. */
10678 /* cand2 is built-in; prefer cand1. */
10683 /* For candidates of a multi-versioned function, make the version with
10684 the highest priority win. This version will be checked for dispatching
10685 first. If this version can be inlined into the caller, the front-end
10686 will simply make a direct call to this function. */
10688 if (TREE_CODE (cand1
->fn
) == FUNCTION_DECL
10689 && DECL_FUNCTION_VERSIONED (cand1
->fn
)
10690 && TREE_CODE (cand2
->fn
) == FUNCTION_DECL
10691 && DECL_FUNCTION_VERSIONED (cand2
->fn
))
10693 tree f1
= TREE_TYPE (cand1
->fn
);
10694 tree f2
= TREE_TYPE (cand2
->fn
);
10695 tree p1
= TYPE_ARG_TYPES (f1
);
10696 tree p2
= TYPE_ARG_TYPES (f2
);
10698 /* Check if cand1->fn and cand2->fn are versions of the same function. It
10699 is possible that cand1->fn and cand2->fn are function versions but of
10700 different functions. Check types to see if they are versions of the same
10702 if (compparms (p1
, p2
)
10703 && same_type_p (TREE_TYPE (f1
), TREE_TYPE (f2
)))
10705 /* Always make the version with the higher priority, more
10706 specialized, win. */
10707 gcc_assert (targetm
.compare_version_priority
);
10708 if (targetm
.compare_version_priority (cand1
->fn
, cand2
->fn
) >= 0)
10715 /* If the two function declarations represent the same function (this can
10716 happen with declarations in multiple scopes and arg-dependent lookup),
10717 arbitrarily choose one. But first make sure the default args we're
10719 if (DECL_P (cand1
->fn
) && DECL_P (cand2
->fn
)
10720 && equal_functions (cand1
->fn
, cand2
->fn
))
10722 tree parms1
= TYPE_ARG_TYPES (TREE_TYPE (cand1
->fn
));
10723 tree parms2
= TYPE_ARG_TYPES (TREE_TYPE (cand2
->fn
));
10725 gcc_assert (!DECL_CONSTRUCTOR_P (cand1
->fn
));
10727 for (i
= 0; i
< len
; ++i
)
10729 /* Don't crash if the fn is variadic. */
10732 parms1
= TREE_CHAIN (parms1
);
10733 parms2
= TREE_CHAIN (parms2
);
10737 parms1
= TREE_CHAIN (parms1
);
10739 parms2
= TREE_CHAIN (parms2
);
10741 for (; parms1
; ++i
)
10743 if (!cp_tree_equal (TREE_PURPOSE (parms1
),
10744 TREE_PURPOSE (parms2
)))
10748 if (complain
& tf_error
)
10750 auto_diagnostic_group d
;
10751 if (permerror (input_location
,
10752 "default argument mismatch in "
10753 "overload resolution"))
10755 inform (DECL_SOURCE_LOCATION (cand1
->fn
),
10756 " candidate 1: %q#F", cand1
->fn
);
10757 inform (DECL_SOURCE_LOCATION (cand2
->fn
),
10758 " candidate 2: %q#F", cand2
->fn
);
10765 add_warning (cand1
, cand2
);
10768 parms1
= TREE_CHAIN (parms1
);
10769 parms2
= TREE_CHAIN (parms2
);
10777 /* Extension: If the worst conversion for one candidate is worse than the
10778 worst conversion for the other, take the first. */
10779 if (!pedantic
&& (complain
& tf_warning_or_error
))
10781 conversion_rank rank1
= cr_identity
, rank2
= cr_identity
;
10782 struct z_candidate
*w
= 0, *l
= 0;
10784 for (i
= 0; i
< len
; ++i
)
10786 if (CONVERSION_RANK (cand1
->convs
[i
+off1
]) > rank1
)
10787 rank1
= CONVERSION_RANK (cand1
->convs
[i
+off1
]);
10788 if (CONVERSION_RANK (cand2
->convs
[i
+ off2
]) > rank2
)
10789 rank2
= CONVERSION_RANK (cand2
->convs
[i
+ off2
]);
10792 winner
= 1, w
= cand1
, l
= cand2
;
10794 winner
= -1, w
= cand2
, l
= cand1
;
10797 /* Don't choose a deleted function over ambiguity. */
10798 if (DECL_P (w
->fn
) && DECL_DELETED_FN (w
->fn
))
10802 auto_diagnostic_group d
;
10803 pedwarn (input_location
, 0,
10804 "ISO C++ says that these are ambiguous, even "
10805 "though the worst conversion for the first is better than "
10806 "the worst conversion for the second:");
10807 print_z_candidate (input_location
, _("candidate 1:"), w
);
10808 print_z_candidate (input_location
, _("candidate 2:"), l
);
10811 add_warning (w
, l
);
10816 gcc_assert (!winner
);
10820 /* Given a list of candidates for overloading, find the best one, if any.
10821 This algorithm has a worst case of O(2n) (winner is last), and a best
10822 case of O(n/2) (totally ambiguous); much better than a sorting
10825 static struct z_candidate
*
10826 tourney (struct z_candidate
*candidates
, tsubst_flags_t complain
)
10828 struct z_candidate
*champ
= candidates
, *challenger
;
10830 int champ_compared_to_predecessor
= 0;
10832 /* Walk through the list once, comparing each current champ to the next
10833 candidate, knocking out a candidate or two with each comparison. */
10835 for (challenger
= champ
->next
; challenger
; )
10837 fate
= joust (champ
, challenger
, 0, complain
);
10839 challenger
= challenger
->next
;
10844 champ
= challenger
->next
;
10847 champ_compared_to_predecessor
= 0;
10851 champ
= challenger
;
10852 champ_compared_to_predecessor
= 1;
10855 challenger
= champ
->next
;
10859 /* Make sure the champ is better than all the candidates it hasn't yet
10860 been compared to. */
10862 for (challenger
= candidates
;
10863 challenger
!= champ
10864 && !(champ_compared_to_predecessor
&& challenger
->next
== champ
);
10865 challenger
= challenger
->next
)
10867 fate
= joust (champ
, challenger
, 0, complain
);
10875 /* Returns nonzero if things of type FROM can be converted to TO. */
10878 can_convert (tree to
, tree from
, tsubst_flags_t complain
)
10880 tree arg
= NULL_TREE
;
10881 /* implicit_conversion only considers user-defined conversions
10882 if it has an expression for the call argument list. */
10883 if (CLASS_TYPE_P (from
) || CLASS_TYPE_P (to
))
10884 arg
= build1 (CAST_EXPR
, from
, NULL_TREE
);
10885 return can_convert_arg (to
, from
, arg
, LOOKUP_IMPLICIT
, complain
);
10888 /* Returns nonzero if things of type FROM can be converted to TO with a
10889 standard conversion. */
10892 can_convert_standard (tree to
, tree from
, tsubst_flags_t complain
)
10894 return can_convert_arg (to
, from
, NULL_TREE
, LOOKUP_IMPLICIT
, complain
);
10897 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
10900 can_convert_arg (tree to
, tree from
, tree arg
, int flags
,
10901 tsubst_flags_t complain
)
10907 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10908 p
= conversion_obstack_alloc (0);
10909 /* We want to discard any access checks done for this test,
10910 as we might not be in the appropriate access context and
10911 we'll do the check again when we actually perform the
10913 push_deferring_access_checks (dk_deferred
);
10915 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10917 ok_p
= (t
&& !t
->bad_p
);
10919 /* Discard the access checks now. */
10920 pop_deferring_access_checks ();
10921 /* Free all the conversions we allocated. */
10922 obstack_free (&conversion_obstack
, p
);
10927 /* Like can_convert_arg, but allows dubious conversions as well. */
10930 can_convert_arg_bad (tree to
, tree from
, tree arg
, int flags
,
10931 tsubst_flags_t complain
)
10936 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10937 p
= conversion_obstack_alloc (0);
10938 /* Try to perform the conversion. */
10939 t
= implicit_conversion (to
, from
, arg
, /*c_cast_p=*/false,
10941 /* Free all the conversions we allocated. */
10942 obstack_free (&conversion_obstack
, p
);
10947 /* Convert EXPR to TYPE. Return the converted expression.
10949 Note that we allow bad conversions here because by the time we get to
10950 this point we are committed to doing the conversion. If we end up
10951 doing a bad conversion, convert_like will complain. */
10954 perform_implicit_conversion_flags (tree type
, tree expr
,
10955 tsubst_flags_t complain
, int flags
)
10959 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
10961 if (TYPE_REF_P (type
))
10962 expr
= mark_lvalue_use (expr
);
10964 expr
= mark_rvalue_use (expr
);
10966 if (error_operand_p (expr
))
10967 return error_mark_node
;
10969 /* Get the high-water mark for the CONVERSION_OBSTACK. */
10970 p
= conversion_obstack_alloc (0);
10972 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
10973 /*c_cast_p=*/false,
10978 if (complain
& tf_error
)
10980 /* If expr has unknown type, then it is an overloaded function.
10981 Call instantiate_type to get good error messages. */
10982 if (TREE_TYPE (expr
) == unknown_type_node
)
10983 instantiate_type (type
, expr
, complain
);
10984 else if (invalid_nonstatic_memfn_p (loc
, expr
, complain
))
10985 /* We gave an error. */;
10988 range_label_for_type_mismatch
label (TREE_TYPE (expr
), type
);
10989 gcc_rich_location
rich_loc (loc
, &label
);
10990 error_at (&rich_loc
, "could not convert %qE from %qH to %qI",
10991 expr
, TREE_TYPE (expr
), type
);
10994 expr
= error_mark_node
;
10996 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
10998 /* In a template, we are only concerned about determining the
10999 type of non-dependent expressions, so we do not have to
11000 perform the actual conversion. But for initializers, we
11001 need to be able to perform it at instantiation
11002 (or instantiate_non_dependent_expr) time. */
11003 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11004 if (!(flags
& LOOKUP_ONLYCONVERTING
))
11005 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11008 expr
= convert_like (conv
, expr
, complain
);
11010 /* Free all the conversions we allocated. */
11011 obstack_free (&conversion_obstack
, p
);
11017 perform_implicit_conversion (tree type
, tree expr
, tsubst_flags_t complain
)
11019 return perform_implicit_conversion_flags (type
, expr
, complain
,
11023 /* Convert EXPR to TYPE (as a direct-initialization) if that is
11024 permitted. If the conversion is valid, the converted expression is
11025 returned. Otherwise, NULL_TREE is returned, except in the case
11026 that TYPE is a class type; in that case, an error is issued. If
11027 C_CAST_P is true, then this direct-initialization is taking
11028 place as part of a static_cast being attempted as part of a C-style
11032 perform_direct_initialization_if_possible (tree type
,
11035 tsubst_flags_t complain
)
11040 if (type
== error_mark_node
|| error_operand_p (expr
))
11041 return error_mark_node
;
11044 If the destination type is a (possibly cv-qualified) class type:
11046 -- If the initialization is direct-initialization ...,
11047 constructors are considered. ... If no constructor applies, or
11048 the overload resolution is ambiguous, the initialization is
11050 if (CLASS_TYPE_P (type
))
11052 vec
<tree
, va_gc
> *args
= make_tree_vector_single (expr
);
11053 expr
= build_special_member_call (NULL_TREE
, complete_ctor_identifier
,
11054 &args
, type
, LOOKUP_NORMAL
, complain
);
11055 release_tree_vector (args
);
11056 return build_cplus_new (type
, expr
, complain
);
11059 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11060 p
= conversion_obstack_alloc (0);
11062 conv
= implicit_conversion (type
, TREE_TYPE (expr
), expr
,
11064 LOOKUP_NORMAL
, complain
);
11065 if (!conv
|| conv
->bad_p
)
11067 else if (processing_template_decl
&& conv
->kind
!= ck_identity
)
11069 /* In a template, we are only concerned about determining the
11070 type of non-dependent expressions, so we do not have to
11071 perform the actual conversion. But for initializers, we
11072 need to be able to perform it at instantiation
11073 (or instantiate_non_dependent_expr) time. */
11074 expr
= build1 (IMPLICIT_CONV_EXPR
, type
, expr
);
11075 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr
) = true;
11078 expr
= convert_like_real (conv
, expr
, NULL_TREE
, 0,
11079 /*issue_conversion_warnings=*/false,
11083 /* Free all the conversions we allocated. */
11084 obstack_free (&conversion_obstack
, p
);
11089 /* When initializing a reference that lasts longer than a full-expression,
11090 this special rule applies:
11094 The temporary to which the reference is bound or the temporary
11095 that is the complete object to which the reference is bound
11096 persists for the lifetime of the reference.
11098 The temporaries created during the evaluation of the expression
11099 initializing the reference, except the temporary to which the
11100 reference is bound, are destroyed at the end of the
11101 full-expression in which they are created.
11103 In that case, we store the converted expression into a new
11104 VAR_DECL in a new scope.
11106 However, we want to be careful not to create temporaries when
11107 they are not required. For example, given:
11110 struct D : public B {};
11114 there is no need to copy the return value from "f"; we can just
11115 extend its lifetime. Similarly, given:
11118 struct T { operator S(); };
11122 we can extend the lifetime of the return value of the conversion
11125 The next several functions are involved in this lifetime extension. */
11127 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
11128 reference is being bound to a temporary. Create and return a new
11129 VAR_DECL with the indicated TYPE; this variable will store the value to
11130 which the reference is bound. */
11133 make_temporary_var_for_ref_to_temp (tree decl
, tree type
)
11135 tree var
= create_temporary_var (type
);
11137 /* Register the variable. */
11139 && (TREE_STATIC (decl
) || CP_DECL_THREAD_LOCAL_P (decl
)))
11141 /* Namespace-scope or local static; give it a mangled name. */
11142 /* FIXME share comdat with decl? */
11144 TREE_STATIC (var
) = TREE_STATIC (decl
);
11145 CP_DECL_THREAD_LOCAL_P (var
) = CP_DECL_THREAD_LOCAL_P (decl
);
11146 set_decl_tls_model (var
, DECL_TLS_MODEL (decl
));
11148 tree name
= mangle_ref_init_variable (decl
);
11149 DECL_NAME (var
) = name
;
11150 SET_DECL_ASSEMBLER_NAME (var
, name
);
11152 var
= pushdecl (var
);
11155 /* Create a new cleanup level if necessary. */
11156 maybe_push_cleanup_level (type
);
11161 /* EXPR is the initializer for a variable DECL of reference or
11162 std::initializer_list type. Create, push and return a new VAR_DECL
11163 for the initializer so that it will live as long as DECL. Any
11164 cleanup for the new variable is returned through CLEANUP, and the
11165 code to initialize the new variable is returned through INITP. */
11168 set_up_extended_ref_temp (tree decl
, tree expr
, vec
<tree
, va_gc
> **cleanups
,
11175 /* Create the temporary variable. */
11176 type
= TREE_TYPE (expr
);
11177 var
= make_temporary_var_for_ref_to_temp (decl
, type
);
11178 layout_decl (var
, 0);
11179 /* If the rvalue is the result of a function call it will be
11180 a TARGET_EXPR. If it is some other construct (such as a
11181 member access expression where the underlying object is
11182 itself the result of a function call), turn it into a
11183 TARGET_EXPR here. It is important that EXPR be a
11184 TARGET_EXPR below since otherwise the INIT_EXPR will
11185 attempt to make a bitwise copy of EXPR to initialize
11187 if (TREE_CODE (expr
) != TARGET_EXPR
)
11188 expr
= get_target_expr (expr
);
11190 if (TREE_CODE (decl
) == FIELD_DECL
11191 && extra_warnings
&& !TREE_NO_WARNING (decl
))
11193 warning (OPT_Wextra
, "a temporary bound to %qD only persists "
11194 "until the constructor exits", decl
);
11195 TREE_NO_WARNING (decl
) = true;
11198 /* Recursively extend temps in this initializer. */
11199 TARGET_EXPR_INITIAL (expr
)
11200 = extend_ref_init_temps (decl
, TARGET_EXPR_INITIAL (expr
), cleanups
);
11202 /* Any reference temp has a non-trivial initializer. */
11203 DECL_NONTRIVIALLY_INITIALIZED_P (var
) = true;
11205 /* If the initializer is constant, put it in DECL_INITIAL so we get
11206 static initialization and use in constant expressions. */
11207 init
= maybe_constant_init (expr
);
11208 /* As in store_init_value. */
11209 init
= cp_fully_fold (init
);
11210 if (TREE_CONSTANT (init
))
11212 if (literal_type_p (type
) && CP_TYPE_CONST_NON_VOLATILE_P (type
))
11214 /* 5.19 says that a constant expression can include an
11215 lvalue-rvalue conversion applied to "a glvalue of literal type
11216 that refers to a non-volatile temporary object initialized
11217 with a constant expression". Rather than try to communicate
11218 that this VAR_DECL is a temporary, just mark it constexpr. */
11219 DECL_DECLARED_CONSTEXPR_P (var
) = true;
11220 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var
) = true;
11221 TREE_CONSTANT (var
) = true;
11222 TREE_READONLY (var
) = true;
11224 DECL_INITIAL (var
) = init
;
11228 /* Create the INIT_EXPR that will initialize the temporary
11230 init
= split_nonconstant_init (var
, expr
);
11231 if (at_function_scope_p ())
11233 add_decl_expr (var
);
11235 if (TREE_STATIC (var
))
11236 init
= add_stmt_to_compound (init
, register_dtor_fn (var
));
11239 tree cleanup
= cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11241 vec_safe_push (*cleanups
, cleanup
);
11244 /* We must be careful to destroy the temporary only
11245 after its initialization has taken place. If the
11246 initialization throws an exception, then the
11247 destructor should not be run. We cannot simply
11248 transform INIT into something like:
11250 (INIT, ({ CLEANUP_STMT; }))
11252 because emit_local_var always treats the
11253 initializer as a full-expression. Thus, the
11254 destructor would run too early; it would run at the
11255 end of initializing the reference variable, rather
11256 than at the end of the block enclosing the
11257 reference variable.
11259 The solution is to pass back a cleanup expression
11260 which the caller is responsible for attaching to
11261 the statement tree. */
11265 rest_of_decl_compilation (var
, /*toplev=*/1, at_eof
);
11266 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
))
11268 if (CP_DECL_THREAD_LOCAL_P (var
))
11269 tls_aggregates
= tree_cons (NULL_TREE
, var
,
11272 static_aggregates
= tree_cons (NULL_TREE
, var
,
11273 static_aggregates
);
11276 /* Check whether the dtor is callable. */
11277 cxx_maybe_build_cleanup (var
, tf_warning_or_error
);
11279 /* Avoid -Wunused-variable warning (c++/38958). */
11280 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type
)
11282 TREE_USED (decl
) = DECL_READ_P (decl
) = true;
11288 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
11289 initializing a variable of that TYPE. */
11292 initialize_reference (tree type
, tree expr
,
11293 int flags
, tsubst_flags_t complain
)
11297 location_t loc
= cp_expr_loc_or_loc (expr
, input_location
);
11299 if (type
== error_mark_node
|| error_operand_p (expr
))
11300 return error_mark_node
;
11302 /* Get the high-water mark for the CONVERSION_OBSTACK. */
11303 p
= conversion_obstack_alloc (0);
11305 conv
= reference_binding (type
, TREE_TYPE (expr
), expr
, /*c_cast_p=*/false,
11307 if (!conv
|| conv
->bad_p
)
11309 if (complain
& tf_error
)
11312 convert_like (conv
, expr
, complain
);
11313 else if (!CP_TYPE_CONST_P (TREE_TYPE (type
))
11314 && !TYPE_REF_IS_RVALUE (type
)
11315 && !lvalue_p (expr
))
11316 error_at (loc
, "invalid initialization of non-const reference of "
11317 "type %qH from an rvalue of type %qI",
11318 type
, TREE_TYPE (expr
));
11320 error_at (loc
, "invalid initialization of reference of type "
11321 "%qH from expression of type %qI", type
,
11324 return error_mark_node
;
11327 if (conv
->kind
== ck_ref_bind
)
11328 /* Perform the conversion. */
11329 expr
= convert_like (conv
, expr
, complain
);
11330 else if (conv
->kind
== ck_ambig
)
11331 /* We gave an error in build_user_type_conversion_1. */
11332 expr
= error_mark_node
;
11334 gcc_unreachable ();
11336 /* Free all the conversions we allocated. */
11337 obstack_free (&conversion_obstack
, p
);
11342 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
11343 which is bound either to a reference or a std::initializer_list. */
11346 extend_ref_init_temps_1 (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11351 if (TREE_CODE (sub
) == COMPOUND_EXPR
)
11353 TREE_OPERAND (sub
, 1)
11354 = extend_ref_init_temps_1 (decl
, TREE_OPERAND (sub
, 1), cleanups
);
11357 if (TREE_CODE (sub
) != ADDR_EXPR
)
11359 /* Deal with binding to a subobject. */
11360 for (p
= &TREE_OPERAND (sub
, 0);
11361 (TREE_CODE (*p
) == COMPONENT_REF
11362 || TREE_CODE (*p
) == ARRAY_REF
); )
11363 p
= &TREE_OPERAND (*p
, 0);
11364 if (TREE_CODE (*p
) == TARGET_EXPR
)
11366 tree subinit
= NULL_TREE
;
11367 *p
= set_up_extended_ref_temp (decl
, *p
, cleanups
, &subinit
);
11368 recompute_tree_invariant_for_addr_expr (sub
);
11370 init
= fold_convert (TREE_TYPE (init
), sub
);
11372 init
= build2 (COMPOUND_EXPR
, TREE_TYPE (init
), subinit
, init
);
11377 /* INIT is part of the initializer for DECL. If there are any
11378 reference or initializer lists being initialized, extend their
11379 lifetime to match that of DECL. */
11382 extend_ref_init_temps (tree decl
, tree init
, vec
<tree
, va_gc
> **cleanups
)
11384 tree type
= TREE_TYPE (init
);
11385 if (processing_template_decl
)
11387 if (TYPE_REF_P (type
))
11388 init
= extend_ref_init_temps_1 (decl
, init
, cleanups
);
11392 if (TREE_CODE (ctor
) == TARGET_EXPR
)
11393 ctor
= TARGET_EXPR_INITIAL (ctor
);
11394 if (TREE_CODE (ctor
) == CONSTRUCTOR
)
11396 if (is_std_init_list (type
))
11398 /* The temporary array underlying a std::initializer_list
11399 is handled like a reference temporary. */
11400 tree array
= CONSTRUCTOR_ELT (ctor
, 0)->value
;
11401 array
= extend_ref_init_temps_1 (decl
, array
, cleanups
);
11402 CONSTRUCTOR_ELT (ctor
, 0)->value
= array
;
11407 constructor_elt
*p
;
11408 vec
<constructor_elt
, va_gc
> *elts
= CONSTRUCTOR_ELTS (ctor
);
11409 FOR_EACH_VEC_SAFE_ELT (elts
, i
, p
)
11410 p
->value
= extend_ref_init_temps (decl
, p
->value
, cleanups
);
11412 recompute_constructor_flags (ctor
);
11413 if (decl_maybe_constant_var_p (decl
) && TREE_CONSTANT (ctor
))
11414 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl
) = true;
11421 /* Returns true iff an initializer for TYPE could contain temporaries that
11422 need to be extended because they are bound to references or
11423 std::initializer_list. */
11426 type_has_extended_temps (tree type
)
11428 type
= strip_array_types (type
);
11429 if (TYPE_REF_P (type
))
11431 if (CLASS_TYPE_P (type
))
11433 if (is_std_init_list (type
))
11435 for (tree f
= next_initializable_field (TYPE_FIELDS (type
));
11436 f
; f
= next_initializable_field (DECL_CHAIN (f
)))
11437 if (type_has_extended_temps (TREE_TYPE (f
)))
11443 /* Returns true iff TYPE is some variant of std::initializer_list. */
11446 is_std_init_list (tree type
)
11448 if (!TYPE_P (type
))
11450 if (cxx_dialect
== cxx98
)
11452 /* Look through typedefs. */
11453 type
= TYPE_MAIN_VARIANT (type
);
11454 return (CLASS_TYPE_P (type
)
11455 && CP_TYPE_CONTEXT (type
) == std_node
11456 && init_list_identifier
== DECL_NAME (TYPE_NAME (type
)));
11459 /* Returns true iff DECL is a list constructor: i.e. a constructor which
11460 will accept an argument list of a single std::initializer_list<T>. */
11463 is_list_ctor (tree decl
)
11465 tree args
= FUNCTION_FIRST_USER_PARMTYPE (decl
);
11468 if (!args
|| args
== void_list_node
)
11471 arg
= non_reference (TREE_VALUE (args
));
11472 if (!is_std_init_list (arg
))
11475 args
= TREE_CHAIN (args
);
11477 if (args
&& args
!= void_list_node
&& !TREE_PURPOSE (args
))
11478 /* There are more non-defaulted parms. */
11484 #include "gt-cp-call.h"