1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987-2015 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com) and
4 modified by Brendan Kehoe (brendan@cygnus.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* High-level class interface. */
27 #include "coretypes.h"
32 #include "double-int.h"
39 #include "stor-layout.h"
40 #include "trans-mem.h"
41 #include "stringpool.h"
45 #include "diagnostic-core.h"
49 #include "langhooks.h"
50 #include "c-family/c-objc.h"
54 #include "plugin-api.h"
55 #include "hard-reg-set.h"
61 #include "internal-fn.h"
63 /* The various kinds of conversion. */
65 typedef enum conversion_kind {
81 /* The rank of the conversion. Order of the enumerals matters; better
82 conversions should come earlier in the list. */
84 typedef enum conversion_rank {
95 /* An implicit conversion sequence, in the sense of [over.best.ics].
96 The first conversion to be performed is at the end of the chain.
97 That conversion is always a cr_identity conversion. */
99 typedef struct conversion conversion;
101 /* The kind of conversion represented by this step. */
102 conversion_kind kind;
103 /* The rank of this conversion. */
104 conversion_rank rank;
105 BOOL_BITFIELD user_conv_p : 1;
106 BOOL_BITFIELD ellipsis_p : 1;
107 BOOL_BITFIELD this_p : 1;
108 /* True if this conversion would be permitted with a bending of
109 language standards, e.g. disregarding pointer qualifiers or
110 converting integers to pointers. */
111 BOOL_BITFIELD bad_p : 1;
112 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
113 temporary should be created to hold the result of the
115 BOOL_BITFIELD need_temporary_p : 1;
116 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
117 from a pointer-to-derived to pointer-to-base is being performed. */
118 BOOL_BITFIELD base_p : 1;
119 /* If KIND is ck_ref_bind, true when either an lvalue reference is
120 being bound to an lvalue expression or an rvalue reference is
121 being bound to an rvalue expression. If KIND is ck_rvalue,
122 true when we should treat an lvalue as an rvalue (12.8p33). If
123 KIND is ck_base, always false. */
124 BOOL_BITFIELD rvaluedness_matches_p: 1;
125 BOOL_BITFIELD check_narrowing: 1;
126 /* The type of the expression resulting from the conversion. */
129 /* The next conversion in the chain. Since the conversions are
130 arranged from outermost to innermost, the NEXT conversion will
131 actually be performed before this conversion. This variant is
132 used only when KIND is neither ck_identity, ck_ambig nor
133 ck_list. Please use the next_conversion function instead
134 of using this field directly. */
136 /* The expression at the beginning of the conversion chain. This
137 variant is used only if KIND is ck_identity or ck_ambig. */
139 /* The array of conversions for an initializer_list, so this
140 variant is used only when KIN D is ck_list. */
143 /* The function candidate corresponding to this conversion
144 sequence. This field is only used if KIND is ck_user. */
145 struct z_candidate *cand;
148 #define CONVERSION_RANK(NODE) \
149 ((NODE)->bad_p ? cr_bad \
150 : (NODE)->ellipsis_p ? cr_ellipsis \
151 : (NODE)->user_conv_p ? cr_user \
154 #define BAD_CONVERSION_RANK(NODE) \
155 ((NODE)->ellipsis_p ? cr_ellipsis \
156 : (NODE)->user_conv_p ? cr_user \
159 static struct obstack conversion_obstack;
160 static bool conversion_obstack_initialized;
161 struct rejection_reason;
163 static struct z_candidate * tourney (struct z_candidate *, tsubst_flags_t);
164 static int equal_functions (tree, tree);
165 static int joust (struct z_candidate *, struct z_candidate *, bool,
167 static int compare_ics (conversion *, conversion *);
168 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
169 static tree build_java_interface_fn_ref (tree, tree);
170 #define convert_like(CONV, EXPR, COMPLAIN) \
171 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
172 /*issue_conversion_warnings=*/true, \
173 /*c_cast_p=*/false, (COMPLAIN))
174 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
175 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
176 /*issue_conversion_warnings=*/true, \
177 /*c_cast_p=*/false, (COMPLAIN))
178 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
179 bool, tsubst_flags_t);
180 static void op_error (location_t, enum tree_code, enum tree_code, tree,
182 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int,
184 static void print_z_candidate (location_t, const char *, struct z_candidate *);
185 static void print_z_candidates (location_t, struct z_candidate *);
186 static tree build_this (tree);
187 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
188 static bool any_strictly_viable (struct z_candidate *);
189 static struct z_candidate *add_template_candidate
190 (struct z_candidate **, tree, tree, tree, tree, const vec<tree, va_gc> *,
191 tree, tree, tree, int, unification_kind_t, tsubst_flags_t);
192 static struct z_candidate *add_template_candidate_real
193 (struct z_candidate **, tree, tree, tree, tree, const vec<tree, va_gc> *,
194 tree, tree, tree, int, tree, unification_kind_t, tsubst_flags_t);
195 static struct z_candidate *add_template_conv_candidate
196 (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *,
197 tree, tree, tree, tsubst_flags_t);
198 static void add_builtin_candidates
199 (struct z_candidate **, enum tree_code, enum tree_code,
200 tree, tree *, int, tsubst_flags_t);
201 static void add_builtin_candidate
202 (struct z_candidate **, enum tree_code, enum tree_code,
203 tree, tree, tree, tree *, tree *, int, tsubst_flags_t);
204 static bool is_complete (tree);
205 static void build_builtin_candidate
206 (struct z_candidate **, tree, tree, tree, tree *, tree *,
207 int, tsubst_flags_t);
208 static struct z_candidate *add_conv_candidate
209 (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *, tree,
210 tree, tsubst_flags_t);
211 static struct z_candidate *add_function_candidate
212 (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *, tree,
213 tree, int, tsubst_flags_t);
214 static conversion *implicit_conversion (tree, tree, tree, bool, int,
216 static conversion *standard_conversion (tree, tree, tree, bool, int);
217 static conversion *reference_binding (tree, tree, tree, bool, int,
219 static conversion *build_conv (conversion_kind, tree, conversion *);
220 static conversion *build_list_conv (tree, tree, int, tsubst_flags_t);
221 static conversion *next_conversion (conversion *);
222 static bool is_subseq (conversion *, conversion *);
223 static conversion *maybe_handle_ref_bind (conversion **);
224 static void maybe_handle_implicit_object (conversion **);
225 static struct z_candidate *add_candidate
226 (struct z_candidate **, tree, tree, const vec<tree, va_gc> *, size_t,
227 conversion **, tree, tree, int, struct rejection_reason *, int);
228 static tree source_type (conversion *);
229 static void add_warning (struct z_candidate *, struct z_candidate *);
230 static bool reference_compatible_p (tree, tree);
231 static conversion *direct_reference_binding (tree, conversion *);
232 static bool promoted_arithmetic_type_p (tree);
233 static conversion *conditional_conversion (tree, tree, tsubst_flags_t);
234 static char *name_as_c_string (tree, tree, bool *);
235 static tree prep_operand (tree);
236 static void add_candidates (tree, tree, const vec<tree, va_gc> *, tree, tree,
237 bool, tree, tree, int, struct z_candidate **,
239 static conversion *merge_conversion_sequences (conversion *, conversion *);
240 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
242 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
243 NAME can take many forms... */
246 check_dtor_name (tree basetype, tree name)
248 /* Just accept something we've already complained about. */
249 if (name == error_mark_node)
252 if (TREE_CODE (name) == TYPE_DECL)
253 name = TREE_TYPE (name);
254 else if (TYPE_P (name))
256 else if (identifier_p (name))
258 if ((MAYBE_CLASS_TYPE_P (basetype)
259 && name == constructor_name (basetype))
260 || (TREE_CODE (basetype) == ENUMERAL_TYPE
261 && name == TYPE_IDENTIFIER (basetype)))
264 name = get_type_value (name);
270 template <class T> struct S { ~S(); };
274 NAME will be a class template. */
275 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
279 if (!name || name == error_mark_node)
281 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
284 /* We want the address of a function or method. We avoid creating a
285 pointer-to-member function. */
288 build_addr_func (tree function, tsubst_flags_t complain)
290 tree type = TREE_TYPE (function);
292 /* We have to do these by hand to avoid real pointer to member
294 if (TREE_CODE (type) == METHOD_TYPE)
296 if (TREE_CODE (function) == OFFSET_REF)
298 tree object = build_address (TREE_OPERAND (function, 0));
299 return get_member_function_from_ptrfunc (&object,
300 TREE_OPERAND (function, 1),
303 function = build_address (function);
306 function = decay_conversion (function, complain);
311 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
312 POINTER_TYPE to those. Note, pointer to member function types
313 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
314 two variants. build_call_a is the primitive taking an array of
315 arguments, while build_call_n is a wrapper that handles varargs. */
318 build_call_n (tree function, int n, ...)
321 return build_call_a (function, 0, NULL);
324 tree *argarray = XALLOCAVEC (tree, n);
329 for (i = 0; i < n; i++)
330 argarray[i] = va_arg (ap, tree);
332 return build_call_a (function, n, argarray);
336 /* Update various flags in cfun and the call itself based on what is being
337 called. Split out of build_call_a so that bot_manip can use it too. */
340 set_flags_from_callee (tree call)
343 tree decl = get_callee_fndecl (call);
345 /* We check both the decl and the type; a function may be known not to
346 throw without being declared throw(). */
347 nothrow = decl && TREE_NOTHROW (decl);
348 if (CALL_EXPR_FN (call))
349 nothrow |= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call))));
350 else if (internal_fn_flags (CALL_EXPR_IFN (call)) & ECF_NOTHROW)
353 if (!nothrow && at_function_scope_p () && cfun && cp_function_chain)
354 cp_function_chain->can_throw = 1;
356 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
357 current_function_returns_abnormally = 1;
359 TREE_NOTHROW (call) = nothrow;
363 build_call_a (tree function, int n, tree *argarray)
370 function = build_addr_func (function, tf_warning_or_error);
372 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
373 fntype = TREE_TYPE (TREE_TYPE (function));
374 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
375 || TREE_CODE (fntype) == METHOD_TYPE);
376 result_type = TREE_TYPE (fntype);
377 /* An rvalue has no cv-qualifiers. */
378 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
379 result_type = cv_unqualified (result_type);
381 function = build_call_array_loc (input_location,
382 result_type, function, n, argarray);
383 set_flags_from_callee (function);
385 decl = get_callee_fndecl (function);
387 if (decl && !TREE_USED (decl))
389 /* We invoke build_call directly for several library
390 functions. These may have been declared normally if
391 we're building libgcc, so we can't just check
393 gcc_assert (DECL_ARTIFICIAL (decl)
394 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
399 require_complete_eh_spec_types (fntype, decl);
401 TREE_HAS_CONSTRUCTOR (function) = (decl && DECL_CONSTRUCTOR_P (decl));
403 /* Don't pass empty class objects by value. This is useful
404 for tags in STL, which are used to control overload resolution.
405 We don't need to handle other cases of copying empty classes. */
406 if (! decl || ! DECL_BUILT_IN (decl))
407 for (i = 0; i < n; i++)
409 tree arg = CALL_EXPR_ARG (function, i);
410 if (is_empty_class (TREE_TYPE (arg))
411 && ! TREE_ADDRESSABLE (TREE_TYPE (arg)))
413 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (arg));
414 arg = build2 (COMPOUND_EXPR, TREE_TYPE (t), arg, t);
415 CALL_EXPR_ARG (function, i) = arg;
422 /* Build something of the form ptr->method (args)
423 or object.method (args). This can also build
424 calls to constructors, and find friends.
426 Member functions always take their class variable
429 INSTANCE is a class instance.
431 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
433 PARMS help to figure out what that NAME really refers to.
435 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
436 down to the real instance type to use for access checking. We need this
437 information to get protected accesses correct.
439 FLAGS is the logical disjunction of zero or more LOOKUP_
440 flags. See cp-tree.h for more info.
442 If this is all OK, calls build_function_call with the resolved
445 This function must also handle being called to perform
446 initialization, promotion/coercion of arguments, and
447 instantiation of default parameters.
449 Note that NAME may refer to an instance variable name. If
450 `operator()()' is defined for the type of that field, then we return
453 /* New overloading code. */
455 typedef struct z_candidate z_candidate;
457 typedef struct candidate_warning candidate_warning;
458 struct candidate_warning {
460 candidate_warning *next;
463 /* Information for providing diagnostics about why overloading failed. */
465 enum rejection_reason_code {
468 rr_explicit_conversion,
469 rr_template_conversion,
471 rr_bad_arg_conversion,
472 rr_template_unification,
476 struct conversion_info {
477 /* The index of the argument, 0-based. */
479 /* The actual argument or its type. */
481 /* The type of the parameter. */
485 struct rejection_reason {
486 enum rejection_reason_code code;
488 /* Information about an arity mismatch. */
490 /* The expected number of arguments. */
492 /* The actual number of arguments in the call. */
494 /* Whether the call was a varargs call. */
497 /* Information about an argument conversion mismatch. */
498 struct conversion_info conversion;
499 /* Same, but for bad argument conversions. */
500 struct conversion_info bad_conversion;
501 /* Information about template unification failures. These are the
502 parameters passed to fn_type_unification. */
510 unification_kind_t strict;
512 } template_unification;
513 /* Information about template instantiation failures. These are the
514 parameters passed to instantiate_template. */
518 } template_instantiation;
523 /* The FUNCTION_DECL that will be called if this candidate is
524 selected by overload resolution. */
526 /* If not NULL_TREE, the first argument to use when calling this
529 /* The rest of the arguments to use when calling this function. If
530 there are no further arguments this may be NULL or it may be an
532 const vec<tree, va_gc> *args;
533 /* The implicit conversion sequences for each of the arguments to
536 /* The number of implicit conversion sequences. */
538 /* If FN is a user-defined conversion, the standard conversion
539 sequence from the type returned by FN to the desired destination
541 conversion *second_conv;
542 struct rejection_reason *reason;
543 /* If FN is a member function, the binfo indicating the path used to
544 qualify the name of FN at the call site. This path is used to
545 determine whether or not FN is accessible if it is selected by
546 overload resolution. The DECL_CONTEXT of FN will always be a
547 (possibly improper) base of this binfo. */
549 /* If FN is a non-static member function, the binfo indicating the
550 subobject to which the `this' pointer should be converted if FN
551 is selected by overload resolution. The type pointed to by
552 the `this' pointer must correspond to the most derived class
553 indicated by the CONVERSION_PATH. */
554 tree conversion_path;
557 candidate_warning *warnings;
561 /* The flags active in add_candidate. */
565 /* Returns true iff T is a null pointer constant in the sense of
569 null_ptr_cst_p (tree t)
573 A null pointer constant is an integral constant expression
574 (_expr.const_) rvalue of integer type that evaluates to zero or
575 an rvalue of type std::nullptr_t. */
576 if (NULLPTR_TYPE_P (TREE_TYPE (t)))
578 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
580 /* Core issue 903 says only literal 0 is a null pointer constant. */
581 if (cxx_dialect < cxx11)
582 t = fold_non_dependent_expr (t);
584 if (integer_zerop (t) && !TREE_OVERFLOW (t))
590 /* Returns true iff T is a null member pointer value (4.11). */
593 null_member_pointer_value_p (tree t)
595 tree type = TREE_TYPE (t);
598 else if (TYPE_PTRMEMFUNC_P (type))
599 return (TREE_CODE (t) == CONSTRUCTOR
600 && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value));
601 else if (TYPE_PTRDATAMEM_P (type))
602 return integer_all_onesp (t);
607 /* Returns nonzero if PARMLIST consists of only default parms,
608 ellipsis, and/or undeduced parameter packs. */
611 sufficient_parms_p (const_tree parmlist)
613 for (; parmlist && parmlist != void_list_node;
614 parmlist = TREE_CHAIN (parmlist))
615 if (!TREE_PURPOSE (parmlist)
616 && !PACK_EXPANSION_P (TREE_VALUE (parmlist)))
621 /* Allocate N bytes of memory from the conversion obstack. The memory
622 is zeroed before being returned. */
625 conversion_obstack_alloc (size_t n)
628 if (!conversion_obstack_initialized)
630 gcc_obstack_init (&conversion_obstack);
631 conversion_obstack_initialized = true;
633 p = obstack_alloc (&conversion_obstack, n);
638 /* Allocate rejection reasons. */
640 static struct rejection_reason *
641 alloc_rejection (enum rejection_reason_code code)
643 struct rejection_reason *p;
644 p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p);
649 static struct rejection_reason *
650 arity_rejection (tree first_arg, int expected, int actual)
652 struct rejection_reason *r = alloc_rejection (rr_arity);
653 int adjust = first_arg != NULL_TREE;
654 r->u.arity.expected = expected - adjust;
655 r->u.arity.actual = actual - adjust;
659 static struct rejection_reason *
660 arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
662 struct rejection_reason *r = alloc_rejection (rr_arg_conversion);
663 int adjust = first_arg != NULL_TREE;
664 r->u.conversion.n_arg = n_arg - adjust;
665 r->u.conversion.from = from;
666 r->u.conversion.to_type = to;
670 static struct rejection_reason *
671 bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
673 struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion);
674 int adjust = first_arg != NULL_TREE;
675 r->u.bad_conversion.n_arg = n_arg - adjust;
676 r->u.bad_conversion.from = from;
677 r->u.bad_conversion.to_type = to;
681 static struct rejection_reason *
682 explicit_conversion_rejection (tree from, tree to)
684 struct rejection_reason *r = alloc_rejection (rr_explicit_conversion);
685 r->u.conversion.n_arg = 0;
686 r->u.conversion.from = from;
687 r->u.conversion.to_type = to;
691 static struct rejection_reason *
692 template_conversion_rejection (tree from, tree to)
694 struct rejection_reason *r = alloc_rejection (rr_template_conversion);
695 r->u.conversion.n_arg = 0;
696 r->u.conversion.from = from;
697 r->u.conversion.to_type = to;
701 static struct rejection_reason *
702 template_unification_rejection (tree tmpl, tree explicit_targs, tree targs,
703 const tree *args, unsigned int nargs,
704 tree return_type, unification_kind_t strict,
707 size_t args_n_bytes = sizeof (*args) * nargs;
708 tree *args1 = (tree *) conversion_obstack_alloc (args_n_bytes);
709 struct rejection_reason *r = alloc_rejection (rr_template_unification);
710 r->u.template_unification.tmpl = tmpl;
711 r->u.template_unification.explicit_targs = explicit_targs;
712 r->u.template_unification.num_targs = TREE_VEC_LENGTH (targs);
713 /* Copy args to our own storage. */
714 memcpy (args1, args, args_n_bytes);
715 r->u.template_unification.args = args1;
716 r->u.template_unification.nargs = nargs;
717 r->u.template_unification.return_type = return_type;
718 r->u.template_unification.strict = strict;
719 r->u.template_unification.flags = flags;
723 static struct rejection_reason *
724 template_unification_error_rejection (void)
726 return alloc_rejection (rr_template_unification);
729 static struct rejection_reason *
730 invalid_copy_with_fn_template_rejection (void)
732 struct rejection_reason *r = alloc_rejection (rr_invalid_copy);
736 /* Dynamically allocate a conversion. */
739 alloc_conversion (conversion_kind kind)
742 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
747 #ifdef ENABLE_CHECKING
749 /* Make sure that all memory on the conversion obstack has been
753 validate_conversion_obstack (void)
755 if (conversion_obstack_initialized)
756 gcc_assert ((obstack_next_free (&conversion_obstack)
757 == obstack_base (&conversion_obstack)));
760 #endif /* ENABLE_CHECKING */
762 /* Dynamically allocate an array of N conversions. */
765 alloc_conversions (size_t n)
767 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
771 build_conv (conversion_kind code, tree type, conversion *from)
774 conversion_rank rank = CONVERSION_RANK (from);
776 /* Note that the caller is responsible for filling in t->cand for
777 user-defined conversions. */
778 t = alloc_conversion (code);
801 t->user_conv_p = (code == ck_user || from->user_conv_p);
802 t->bad_p = from->bad_p;
807 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
808 specialization of std::initializer_list<T>, if such a conversion is
812 build_list_conv (tree type, tree ctor, int flags, tsubst_flags_t complain)
814 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
815 unsigned len = CONSTRUCTOR_NELTS (ctor);
816 conversion **subconvs = alloc_conversions (len);
821 /* Within a list-initialization we can have more user-defined
823 flags &= ~LOOKUP_NO_CONVERSION;
824 /* But no narrowing conversions. */
825 flags |= LOOKUP_NO_NARROWING;
827 /* Can't make an array of these types. */
828 if (TREE_CODE (elttype) == REFERENCE_TYPE
829 || TREE_CODE (elttype) == FUNCTION_TYPE
830 || VOID_TYPE_P (elttype))
833 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
836 = implicit_conversion (elttype, TREE_TYPE (val), val,
837 false, flags, complain);
844 t = alloc_conversion (ck_list);
846 t->u.list = subconvs;
849 for (i = 0; i < len; ++i)
851 conversion *sub = subconvs[i];
852 if (sub->rank > t->rank)
854 if (sub->user_conv_p)
855 t->user_conv_p = true;
863 /* Return the next conversion of the conversion chain (if applicable),
864 or NULL otherwise. Please use this function instead of directly
865 accessing fields of struct conversion. */
868 next_conversion (conversion *conv)
871 || conv->kind == ck_identity
872 || conv->kind == ck_ambig
873 || conv->kind == ck_list)
878 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
879 is a valid aggregate initializer for array type ATYPE. */
882 can_convert_array (tree atype, tree ctor, int flags, tsubst_flags_t complain)
885 tree elttype = TREE_TYPE (atype);
886 for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
888 tree val = CONSTRUCTOR_ELT (ctor, i)->value;
890 if (TREE_CODE (elttype) == ARRAY_TYPE
891 && TREE_CODE (val) == CONSTRUCTOR)
892 ok = can_convert_array (elttype, val, flags, complain);
894 ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags,
902 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
903 aggregate class, if such a conversion is possible. */
906 build_aggr_conv (tree type, tree ctor, int flags, tsubst_flags_t complain)
908 unsigned HOST_WIDE_INT i = 0;
910 tree field = next_initializable_field (TYPE_FIELDS (type));
911 tree empty_ctor = NULL_TREE;
913 ctor = reshape_init (type, ctor, tf_none);
914 if (ctor == error_mark_node)
917 /* The conversions within the init-list aren't affected by the enclosing
918 context; they're always simple copy-initialization. */
919 flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING;
921 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
923 tree ftype = TREE_TYPE (field);
927 if (i < CONSTRUCTOR_NELTS (ctor))
928 val = CONSTRUCTOR_ELT (ctor, i)->value;
929 else if (TREE_CODE (ftype) == REFERENCE_TYPE)
930 /* Value-initialization of reference is ill-formed. */
934 if (empty_ctor == NULL_TREE)
935 empty_ctor = build_constructor (init_list_type_node, NULL);
940 if (TREE_CODE (ftype) == ARRAY_TYPE
941 && TREE_CODE (val) == CONSTRUCTOR)
942 ok = can_convert_array (ftype, val, flags, complain);
944 ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags,
950 if (TREE_CODE (type) == UNION_TYPE)
954 if (i < CONSTRUCTOR_NELTS (ctor))
957 c = alloc_conversion (ck_aggr);
960 c->user_conv_p = true;
961 c->check_narrowing = true;
966 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
967 array type, if such a conversion is possible. */
970 build_array_conv (tree type, tree ctor, int flags, tsubst_flags_t complain)
973 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
974 tree elttype = TREE_TYPE (type);
979 enum conversion_rank rank = cr_exact;
981 /* We might need to propagate the size from the element to the array. */
982 complete_type (type);
984 if (TYPE_DOMAIN (type)
985 && !variably_modified_type_p (TYPE_DOMAIN (type), NULL_TREE))
987 unsigned HOST_WIDE_INT alen = tree_to_uhwi (array_type_nelts_top (type));
992 flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING;
994 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
997 = implicit_conversion (elttype, TREE_TYPE (val), val,
998 false, flags, complain);
1002 if (sub->rank > rank)
1004 if (sub->user_conv_p)
1010 c = alloc_conversion (ck_aggr);
1013 c->user_conv_p = user;
1019 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1020 complex type, if such a conversion is possible. */
1023 build_complex_conv (tree type, tree ctor, int flags,
1024 tsubst_flags_t complain)
1027 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
1028 tree elttype = TREE_TYPE (type);
1033 enum conversion_rank rank = cr_exact;
1038 flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING;
1040 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
1043 = implicit_conversion (elttype, TREE_TYPE (val), val,
1044 false, flags, complain);
1048 if (sub->rank > rank)
1050 if (sub->user_conv_p)
1056 c = alloc_conversion (ck_aggr);
1059 c->user_conv_p = user;
1065 /* Build a representation of the identity conversion from EXPR to
1066 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1069 build_identity_conv (tree type, tree expr)
1073 c = alloc_conversion (ck_identity);
1080 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1081 were multiple user-defined conversions to accomplish the job.
1082 Build a conversion that indicates that ambiguity. */
1085 build_ambiguous_conv (tree type, tree expr)
1089 c = alloc_conversion (ck_ambig);
1097 strip_top_quals (tree t)
1099 if (TREE_CODE (t) == ARRAY_TYPE)
1101 return cp_build_qualified_type (t, 0);
1104 /* Returns the standard conversion path (see [conv]) from type FROM to type
1105 TO, if any. For proper handling of null pointer constants, you must
1106 also pass the expression EXPR to convert from. If C_CAST_P is true,
1107 this conversion is coming from a C-style cast. */
1110 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
1113 enum tree_code fcode, tcode;
1115 bool fromref = false;
1118 to = non_reference (to);
1119 if (TREE_CODE (from) == REFERENCE_TYPE)
1122 from = TREE_TYPE (from);
1125 to = strip_top_quals (to);
1126 from = strip_top_quals (from);
1128 if (expr && type_unknown_p (expr))
1130 if (TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
1132 tsubst_flags_t tflags = tf_conv;
1133 expr = instantiate_type (to, expr, tflags);
1134 if (expr == error_mark_node)
1136 from = TREE_TYPE (expr);
1138 else if (TREE_CODE (to) == BOOLEAN_TYPE)
1140 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1141 expr = resolve_nondeduced_context (expr);
1142 from = TREE_TYPE (expr);
1146 fcode = TREE_CODE (from);
1147 tcode = TREE_CODE (to);
1149 conv = build_identity_conv (from, expr);
1150 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
1152 from = type_decays_to (from);
1153 fcode = TREE_CODE (from);
1154 conv = build_conv (ck_lvalue, from, conv);
1156 else if (fromref || (expr && lvalue_p (expr)))
1161 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
1164 from = strip_top_quals (bitfield_type);
1165 fcode = TREE_CODE (from);
1168 conv = build_conv (ck_rvalue, from, conv);
1169 if (flags & LOOKUP_PREFER_RVALUE)
1170 conv->rvaluedness_matches_p = true;
1173 /* Allow conversion between `__complex__' data types. */
1174 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
1176 /* The standard conversion sequence to convert FROM to TO is
1177 the standard conversion sequence to perform componentwise
1179 conversion *part_conv = standard_conversion
1180 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
1184 conv = build_conv (part_conv->kind, to, conv);
1185 conv->rank = part_conv->rank;
1193 if (same_type_p (from, to))
1195 if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue)
1196 conv->type = qualified_to;
1201 A null pointer constant can be converted to a pointer type; ... A
1202 null pointer constant of integral type can be converted to an
1203 rvalue of type std::nullptr_t. */
1204 if ((tcode == POINTER_TYPE || TYPE_PTRMEM_P (to)
1205 || NULLPTR_TYPE_P (to))
1206 && ((expr && null_ptr_cst_p (expr))
1207 || NULLPTR_TYPE_P (from)))
1208 conv = build_conv (ck_std, to, conv);
1209 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
1210 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
1212 /* For backwards brain damage compatibility, allow interconversion of
1213 pointers and integers with a pedwarn. */
1214 conv = build_conv (ck_std, to, conv);
1217 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
1219 /* For backwards brain damage compatibility, allow interconversion of
1220 enums and integers with a pedwarn. */
1221 conv = build_conv (ck_std, to, conv);
1224 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
1225 || (TYPE_PTRDATAMEM_P (to) && TYPE_PTRDATAMEM_P (from)))
1230 if (tcode == POINTER_TYPE
1231 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
1234 else if (VOID_TYPE_P (TREE_TYPE (to))
1235 && !TYPE_PTRDATAMEM_P (from)
1236 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
1238 tree nfrom = TREE_TYPE (from);
1239 /* Don't try to apply restrict to void. */
1240 int quals = cp_type_quals (nfrom) & ~TYPE_QUAL_RESTRICT;
1241 from = build_pointer_type
1242 (cp_build_qualified_type (void_type_node, quals));
1243 conv = build_conv (ck_ptr, from, conv);
1245 else if (TYPE_PTRDATAMEM_P (from))
1247 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
1248 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
1250 if (DERIVED_FROM_P (fbase, tbase)
1251 && (same_type_ignoring_top_level_qualifiers_p
1252 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
1253 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
1255 from = build_ptrmem_type (tbase,
1256 TYPE_PTRMEM_POINTED_TO_TYPE (from));
1257 conv = build_conv (ck_pmem, from, conv);
1259 else if (!same_type_p (fbase, tbase))
1262 else if (CLASS_TYPE_P (TREE_TYPE (from))
1263 && CLASS_TYPE_P (TREE_TYPE (to))
1266 An rvalue of type "pointer to cv D," where D is a
1267 class type, can be converted to an rvalue of type
1268 "pointer to cv B," where B is a base class (clause
1269 _class.derived_) of D. If B is an inaccessible
1270 (clause _class.access_) or ambiguous
1271 (_class.member.lookup_) base class of D, a program
1272 that necessitates this conversion is ill-formed.
1273 Therefore, we use DERIVED_FROM_P, and do not check
1274 access or uniqueness. */
1275 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
1278 cp_build_qualified_type (TREE_TYPE (to),
1279 cp_type_quals (TREE_TYPE (from)));
1280 from = build_pointer_type (from);
1281 conv = build_conv (ck_ptr, from, conv);
1282 conv->base_p = true;
1285 if (tcode == POINTER_TYPE)
1287 to_pointee = TREE_TYPE (to);
1288 from_pointee = TREE_TYPE (from);
1292 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
1293 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
1296 if (same_type_p (from, to))
1298 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
1299 /* In a C-style cast, we ignore CV-qualification because we
1300 are allowed to perform a static_cast followed by a
1302 conv = build_conv (ck_qual, to, conv);
1303 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
1304 conv = build_conv (ck_qual, to, conv);
1305 else if (expr && string_conv_p (to, expr, 0))
1306 /* converting from string constant to char *. */
1307 conv = build_conv (ck_qual, to, conv);
1308 /* Allow conversions among compatible ObjC pointer types (base
1309 conversions have been already handled above). */
1310 else if (c_dialect_objc ()
1311 && objc_compare_types (to, from, -4, NULL_TREE))
1312 conv = build_conv (ck_ptr, to, conv);
1313 else if (ptr_reasonably_similar (to_pointee, from_pointee))
1315 conv = build_conv (ck_ptr, to, conv);
1323 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
1325 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
1326 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
1327 tree fbase = class_of_this_parm (fromfn);
1328 tree tbase = class_of_this_parm (tofn);
1330 if (!DERIVED_FROM_P (fbase, tbase)
1331 || !same_type_p (static_fn_type (fromfn),
1332 static_fn_type (tofn)))
1335 from = build_memfn_type (fromfn,
1337 cp_type_quals (tbase),
1338 type_memfn_rqual (tofn));
1339 from = build_ptrmemfunc_type (build_pointer_type (from));
1340 conv = build_conv (ck_pmem, from, conv);
1341 conv->base_p = true;
1343 else if (tcode == BOOLEAN_TYPE)
1347 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1348 to member type can be converted to a prvalue of type bool. ...
1349 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1350 std::nullptr_t can be converted to a prvalue of type bool; */
1351 if (ARITHMETIC_TYPE_P (from)
1352 || UNSCOPED_ENUM_P (from)
1353 || fcode == POINTER_TYPE
1354 || TYPE_PTRMEM_P (from)
1355 || NULLPTR_TYPE_P (from))
1357 conv = build_conv (ck_std, to, conv);
1358 if (fcode == POINTER_TYPE
1359 || TYPE_PTRDATAMEM_P (from)
1360 || (TYPE_PTRMEMFUNC_P (from)
1361 && conv->rank < cr_pbool)
1362 || NULLPTR_TYPE_P (from))
1363 conv->rank = cr_pbool;
1364 if (NULLPTR_TYPE_P (from) && (flags & LOOKUP_ONLYCONVERTING))
1371 /* We don't check for ENUMERAL_TYPE here because there are no standard
1372 conversions to enum type. */
1373 /* As an extension, allow conversion to complex type. */
1374 else if (ARITHMETIC_TYPE_P (to))
1376 if (! (INTEGRAL_CODE_P (fcode)
1377 || (fcode == REAL_TYPE && !(flags & LOOKUP_NO_NON_INTEGRAL)))
1378 || SCOPED_ENUM_P (from))
1380 conv = build_conv (ck_std, to, conv);
1382 /* Give this a better rank if it's a promotion. */
1383 if (same_type_p (to, type_promotes_to (from))
1384 && next_conversion (conv)->rank <= cr_promotion)
1385 conv->rank = cr_promotion;
1387 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
1388 && vector_types_convertible_p (from, to, false))
1389 return build_conv (ck_std, to, conv);
1390 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
1391 && is_properly_derived_from (from, to))
1393 if (conv->kind == ck_rvalue)
1394 conv = next_conversion (conv);
1395 conv = build_conv (ck_base, to, conv);
1396 /* The derived-to-base conversion indicates the initialization
1397 of a parameter with base type from an object of a derived
1398 type. A temporary object is created to hold the result of
1399 the conversion unless we're binding directly to a reference. */
1400 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
1405 if (flags & LOOKUP_NO_NARROWING)
1406 conv->check_narrowing = true;
1411 /* Returns nonzero if T1 is reference-related to T2. */
1414 reference_related_p (tree t1, tree t2)
1416 if (t1 == error_mark_node || t2 == error_mark_node)
1419 t1 = TYPE_MAIN_VARIANT (t1);
1420 t2 = TYPE_MAIN_VARIANT (t2);
1424 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1425 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1427 return (same_type_p (t1, t2)
1428 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1429 && DERIVED_FROM_P (t1, t2)));
1432 /* Returns nonzero if T1 is reference-compatible with T2. */
1435 reference_compatible_p (tree t1, tree t2)
1439 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1440 reference-related to T2 and cv1 is the same cv-qualification as,
1441 or greater cv-qualification than, cv2. */
1442 return (reference_related_p (t1, t2)
1443 && at_least_as_qualified_p (t1, t2));
1446 /* A reference of the indicated TYPE is being bound directly to the
1447 expression represented by the implicit conversion sequence CONV.
1448 Return a conversion sequence for this binding. */
1451 direct_reference_binding (tree type, conversion *conv)
1455 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1456 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1458 t = TREE_TYPE (type);
1462 When a parameter of reference type binds directly
1463 (_dcl.init.ref_) to an argument expression, the implicit
1464 conversion sequence is the identity conversion, unless the
1465 argument expression has a type that is a derived class of the
1466 parameter type, in which case the implicit conversion sequence is
1467 a derived-to-base Conversion.
1469 If the parameter binds directly to the result of applying a
1470 conversion function to the argument expression, the implicit
1471 conversion sequence is a user-defined conversion sequence
1472 (_over.ics.user_), with the second standard conversion sequence
1473 either an identity conversion or, if the conversion function
1474 returns an entity of a type that is a derived class of the
1475 parameter type, a derived-to-base conversion. */
1476 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1478 /* Represent the derived-to-base conversion. */
1479 conv = build_conv (ck_base, t, conv);
1480 /* We will actually be binding to the base-class subobject in
1481 the derived class, so we mark this conversion appropriately.
1482 That way, convert_like knows not to generate a temporary. */
1483 conv->need_temporary_p = false;
1485 return build_conv (ck_ref_bind, type, conv);
1488 /* Returns the conversion path from type FROM to reference type TO for
1489 purposes of reference binding. For lvalue binding, either pass a
1490 reference type to FROM or an lvalue expression to EXPR. If the
1491 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1492 the conversion returned. If C_CAST_P is true, this
1493 conversion is coming from a C-style cast. */
1496 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags,
1497 tsubst_flags_t complain)
1499 conversion *conv = NULL;
1500 tree to = TREE_TYPE (rto);
1505 cp_lvalue_kind gl_kind;
1508 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1510 expr = instantiate_type (to, expr, tf_none);
1511 if (expr == error_mark_node)
1513 from = TREE_TYPE (expr);
1516 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1518 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1519 /* DR 1288: Otherwise, if the initializer list has a single element
1520 of type E and ... [T's] referenced type is reference-related to E,
1521 the object or reference is initialized from that element... */
1522 if (CONSTRUCTOR_NELTS (expr) == 1)
1524 tree elt = CONSTRUCTOR_ELT (expr, 0)->value;
1525 if (error_operand_p (elt))
1527 tree etype = TREE_TYPE (elt);
1528 if (reference_related_p (to, etype))
1535 /* Otherwise, if T is a reference type, a prvalue temporary of the
1536 type referenced by T is copy-list-initialized or
1537 direct-list-initialized, depending on the kind of initialization
1538 for the reference, and the reference is bound to that temporary. */
1539 conv = implicit_conversion (to, from, expr, c_cast_p,
1540 flags|LOOKUP_NO_TEMP_BIND, complain);
1544 if (TREE_CODE (from) == REFERENCE_TYPE)
1546 from = TREE_TYPE (from);
1547 if (!TYPE_REF_IS_RVALUE (rfrom)
1548 || TREE_CODE (from) == FUNCTION_TYPE)
1549 gl_kind = clk_ordinary;
1551 gl_kind = clk_rvalueref;
1555 gl_kind = lvalue_kind (expr);
1556 if (gl_kind & clk_class)
1557 /* A class prvalue is not a glvalue. */
1562 is_lvalue = gl_kind && !(gl_kind & clk_rvalueref);
1565 if ((gl_kind & clk_bitfield) != 0)
1566 tfrom = unlowered_expr_type (expr);
1568 /* Figure out whether or not the types are reference-related and
1569 reference compatible. We have do do this after stripping
1570 references from FROM. */
1571 related_p = reference_related_p (to, tfrom);
1572 /* If this is a C cast, first convert to an appropriately qualified
1573 type, so that we can later do a const_cast to the desired type. */
1574 if (related_p && c_cast_p
1575 && !at_least_as_qualified_p (to, tfrom))
1576 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1577 compatible_p = reference_compatible_p (to, tfrom);
1579 /* Directly bind reference when target expression's type is compatible with
1580 the reference and expression is an lvalue. In DR391, the wording in
1581 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1582 const and rvalue references to rvalues of compatible class type.
1583 We should also do direct bindings for non-class xvalues. */
1586 || (!(flags & LOOKUP_NO_TEMP_BIND)
1587 && (CLASS_TYPE_P (from)
1588 || TREE_CODE (from) == ARRAY_TYPE))))
1592 If the initializer expression
1594 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1595 is reference-compatible with "cv2 T2,"
1597 the reference is bound directly to the initializer expression
1601 If the initializer expression is an rvalue, with T2 a class type,
1602 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1603 is bound to the object represented by the rvalue or to a sub-object
1604 within that object. */
1606 conv = build_identity_conv (tfrom, expr);
1607 conv = direct_reference_binding (rto, conv);
1609 if (flags & LOOKUP_PREFER_RVALUE)
1610 /* The top-level caller requested that we pretend that the lvalue
1611 be treated as an rvalue. */
1612 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1613 else if (TREE_CODE (rfrom) == REFERENCE_TYPE)
1614 /* Handle rvalue reference to function properly. */
1615 conv->rvaluedness_matches_p
1616 = (TYPE_REF_IS_RVALUE (rto) == TYPE_REF_IS_RVALUE (rfrom));
1618 conv->rvaluedness_matches_p
1619 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1621 if ((gl_kind & clk_bitfield) != 0
1622 || ((gl_kind & clk_packed) != 0 && !TYPE_PACKED (to)))
1623 /* For the purposes of overload resolution, we ignore the fact
1624 this expression is a bitfield or packed field. (In particular,
1625 [over.ics.ref] says specifically that a function with a
1626 non-const reference parameter is viable even if the
1627 argument is a bitfield.)
1629 However, when we actually call the function we must create
1630 a temporary to which to bind the reference. If the
1631 reference is volatile, or isn't const, then we cannot make
1632 a temporary, so we just issue an error when the conversion
1634 conv->need_temporary_p = true;
1636 /* Don't allow binding of lvalues (other than function lvalues) to
1637 rvalue references. */
1638 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1639 && TREE_CODE (to) != FUNCTION_TYPE
1640 && !(flags & LOOKUP_PREFER_RVALUE))
1643 /* Nor the reverse. */
1644 if (!is_lvalue && !TYPE_REF_IS_RVALUE (rto)
1645 && (!CP_TYPE_CONST_NON_VOLATILE_P (to)
1646 || (flags & LOOKUP_NO_RVAL_BIND))
1647 && TREE_CODE (to) != FUNCTION_TYPE)
1655 /* [class.conv.fct] A conversion function is never used to convert a
1656 (possibly cv-qualified) object to the (possibly cv-qualified) same
1657 object type (or a reference to it), to a (possibly cv-qualified) base
1658 class of that type (or a reference to it).... */
1659 else if (CLASS_TYPE_P (from) && !related_p
1660 && !(flags & LOOKUP_NO_CONVERSION))
1664 If the initializer expression
1666 -- has a class type (i.e., T2 is a class type) can be
1667 implicitly converted to an lvalue of type "cv3 T3," where
1668 "cv1 T1" is reference-compatible with "cv3 T3". (this
1669 conversion is selected by enumerating the applicable
1670 conversion functions (_over.match.ref_) and choosing the
1671 best one through overload resolution. (_over.match_).
1673 the reference is bound to the lvalue result of the conversion
1674 in the second case. */
1675 z_candidate *cand = build_user_type_conversion_1 (rto, expr, flags,
1678 return cand->second_conv;
1681 /* From this point on, we conceptually need temporaries, even if we
1682 elide them. Only the cases above are "direct bindings". */
1683 if (flags & LOOKUP_NO_TEMP_BIND)
1688 When a parameter of reference type is not bound directly to an
1689 argument expression, the conversion sequence is the one required
1690 to convert the argument expression to the underlying type of the
1691 reference according to _over.best.ics_. Conceptually, this
1692 conversion sequence corresponds to copy-initializing a temporary
1693 of the underlying type with the argument expression. Any
1694 difference in top-level cv-qualification is subsumed by the
1695 initialization itself and does not constitute a conversion. */
1699 Otherwise, the reference shall be an lvalue reference to a
1700 non-volatile const type, or the reference shall be an rvalue
1703 We try below to treat this as a bad conversion to improve diagnostics,
1704 but if TO is an incomplete class, we need to reject this conversion
1705 now to avoid unnecessary instantiation. */
1706 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto)
1707 && !COMPLETE_TYPE_P (to))
1710 /* We're generating a temporary now, but don't bind any more in the
1711 conversion (specifically, don't slice the temporary returned by a
1712 conversion operator). */
1713 flags |= LOOKUP_NO_TEMP_BIND;
1715 /* Core issue 899: When [copy-]initializing a temporary to be bound
1716 to the first parameter of a copy constructor (12.8) called with
1717 a single argument in the context of direct-initialization,
1718 explicit conversion functions are also considered.
1720 So don't set LOOKUP_ONLYCONVERTING in that case. */
1721 if (!(flags & LOOKUP_COPY_PARM))
1722 flags |= LOOKUP_ONLYCONVERTING;
1725 conv = implicit_conversion (to, from, expr, c_cast_p,
1730 if (conv->user_conv_p)
1732 /* If initializing the temporary used a conversion function,
1733 recalculate the second conversion sequence. */
1734 for (conversion *t = conv; t; t = next_conversion (t))
1735 if (t->kind == ck_user
1736 && DECL_CONV_FN_P (t->cand->fn))
1738 tree ftype = TREE_TYPE (TREE_TYPE (t->cand->fn));
1739 int sflags = (flags|LOOKUP_NO_CONVERSION)&~LOOKUP_NO_TEMP_BIND;
1740 conversion *new_second
1741 = reference_binding (rto, ftype, NULL_TREE, c_cast_p,
1745 return merge_conversion_sequences (t, new_second);
1749 conv = build_conv (ck_ref_bind, rto, conv);
1750 /* This reference binding, unlike those above, requires the
1751 creation of a temporary. */
1752 conv->need_temporary_p = true;
1753 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1757 Otherwise, the reference shall be an lvalue reference to a
1758 non-volatile const type, or the reference shall be an rvalue
1760 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1765 Otherwise, a temporary of type "cv1 T1" is created and
1766 initialized from the initializer expression using the rules for a
1767 non-reference copy initialization. If T1 is reference-related to
1768 T2, cv1 must be the same cv-qualification as, or greater
1769 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1770 if (related_p && !at_least_as_qualified_p (to, from))
1776 /* Returns the implicit conversion sequence (see [over.ics]) from type
1777 FROM to type TO. The optional expression EXPR may affect the
1778 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1779 true, this conversion is coming from a C-style cast. */
1782 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1783 int flags, tsubst_flags_t complain)
1787 if (from == error_mark_node || to == error_mark_node
1788 || expr == error_mark_node)
1791 /* Other flags only apply to the primary function in overload
1792 resolution, or after we've chosen one. */
1793 flags &= (LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION|LOOKUP_COPY_PARM
1794 |LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND|LOOKUP_PREFER_RVALUE
1795 |LOOKUP_NO_NARROWING|LOOKUP_PROTECT|LOOKUP_NO_NON_INTEGRAL);
1797 /* FIXME: actually we don't want warnings either, but we can't just
1798 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1799 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1800 We really ought not to issue that warning until we've committed
1801 to that conversion. */
1802 complain &= ~tf_error;
1804 if (TREE_CODE (to) == REFERENCE_TYPE)
1805 conv = reference_binding (to, from, expr, c_cast_p, flags, complain);
1807 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1812 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1814 if (is_std_init_list (to))
1815 return build_list_conv (to, expr, flags, complain);
1817 /* As an extension, allow list-initialization of _Complex. */
1818 if (TREE_CODE (to) == COMPLEX_TYPE)
1820 conv = build_complex_conv (to, expr, flags, complain);
1825 /* Allow conversion from an initializer-list with one element to a
1827 if (SCALAR_TYPE_P (to))
1829 int nelts = CONSTRUCTOR_NELTS (expr);
1833 elt = build_value_init (to, tf_none);
1834 else if (nelts == 1)
1835 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1837 elt = error_mark_node;
1839 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1840 c_cast_p, flags, complain);
1843 conv->check_narrowing = true;
1844 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1845 /* Too many levels of braces, i.e. '{{1}}'. */
1850 else if (TREE_CODE (to) == ARRAY_TYPE)
1851 return build_array_conv (to, expr, flags, complain);
1854 if (expr != NULL_TREE
1855 && (MAYBE_CLASS_TYPE_P (from)
1856 || MAYBE_CLASS_TYPE_P (to))
1857 && (flags & LOOKUP_NO_CONVERSION) == 0)
1859 struct z_candidate *cand;
1861 if (CLASS_TYPE_P (to)
1862 && BRACE_ENCLOSED_INITIALIZER_P (expr)
1863 && !CLASSTYPE_NON_AGGREGATE (complete_type (to)))
1864 return build_aggr_conv (to, expr, flags, complain);
1866 cand = build_user_type_conversion_1 (to, expr, flags, complain);
1868 conv = cand->second_conv;
1870 /* We used to try to bind a reference to a temporary here, but that
1871 is now handled after the recursive call to this function at the end
1872 of reference_binding. */
1879 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1880 functions. ARGS will not be changed until a single candidate is
1883 static struct z_candidate *
1884 add_candidate (struct z_candidate **candidates,
1885 tree fn, tree first_arg, const vec<tree, va_gc> *args,
1886 size_t num_convs, conversion **convs,
1887 tree access_path, tree conversion_path,
1888 int viable, struct rejection_reason *reason,
1891 struct z_candidate *cand = (struct z_candidate *)
1892 conversion_obstack_alloc (sizeof (struct z_candidate));
1895 cand->first_arg = first_arg;
1897 cand->convs = convs;
1898 cand->num_convs = num_convs;
1899 cand->access_path = access_path;
1900 cand->conversion_path = conversion_path;
1901 cand->viable = viable;
1902 cand->reason = reason;
1903 cand->next = *candidates;
1904 cand->flags = flags;
1910 /* Return the number of remaining arguments in the parameter list
1911 beginning with ARG. */
1914 remaining_arguments (tree arg)
1918 for (n = 0; arg != NULL_TREE && arg != void_list_node;
1919 arg = TREE_CHAIN (arg))
1925 /* Create an overload candidate for the function or method FN called
1926 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1927 FLAGS is passed on to implicit_conversion.
1929 This does not change ARGS.
1931 CTYPE, if non-NULL, is the type we want to pretend this function
1932 comes from for purposes of overload resolution. */
1934 static struct z_candidate *
1935 add_function_candidate (struct z_candidate **candidates,
1936 tree fn, tree ctype, tree first_arg,
1937 const vec<tree, va_gc> *args, tree access_path,
1938 tree conversion_path, int flags,
1939 tsubst_flags_t complain)
1941 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1945 tree orig_first_arg = first_arg;
1948 struct rejection_reason *reason = NULL;
1950 /* At this point we should not see any functions which haven't been
1951 explicitly declared, except for friend functions which will have
1952 been found using argument dependent lookup. */
1953 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1955 /* The `this', `in_chrg' and VTT arguments to constructors are not
1956 considered in overload resolution. */
1957 if (DECL_CONSTRUCTOR_P (fn))
1959 parmlist = skip_artificial_parms_for (fn, parmlist);
1960 skip = num_artificial_parms_for (fn);
1961 if (skip > 0 && first_arg != NULL_TREE)
1964 first_arg = NULL_TREE;
1970 len = vec_safe_length (args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1971 convs = alloc_conversions (len);
1973 /* 13.3.2 - Viable functions [over.match.viable]
1974 First, to be a viable function, a candidate function shall have enough
1975 parameters to agree in number with the arguments in the list.
1977 We need to check this first; otherwise, checking the ICSes might cause
1978 us to produce an ill-formed template instantiation. */
1980 parmnode = parmlist;
1981 for (i = 0; i < len; ++i)
1983 if (parmnode == NULL_TREE || parmnode == void_list_node)
1985 parmnode = TREE_CHAIN (parmnode);
1988 if ((i < len && parmnode)
1989 || !sufficient_parms_p (parmnode))
1991 int remaining = remaining_arguments (parmnode);
1993 reason = arity_rejection (first_arg, i + remaining, len);
1995 /* When looking for a function from a subobject from an implicit
1996 copy/move constructor/operator=, don't consider anything that takes (a
1997 reference to) an unrelated type. See c++/44909 and core 1092. */
1998 else if (parmlist && (flags & LOOKUP_DEFAULTED))
2000 if (DECL_CONSTRUCTOR_P (fn))
2002 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
2003 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
2009 parmnode = chain_index (i-1, parmlist);
2010 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
2015 /* This only applies at the top level. */
2016 flags &= ~LOOKUP_DEFAULTED;
2022 /* Second, for F to be a viable function, there shall exist for each
2023 argument an implicit conversion sequence that converts that argument
2024 to the corresponding parameter of F. */
2026 parmnode = parmlist;
2028 for (i = 0; i < len; ++i)
2030 tree argtype, to_type;
2035 if (parmnode == void_list_node)
2038 if (i == 0 && first_arg != NULL_TREE)
2041 arg = CONST_CAST_TREE (
2042 (*args)[i + skip - (first_arg != NULL_TREE ? 1 : 0)]);
2043 argtype = lvalue_type (arg);
2045 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
2046 && ! DECL_CONSTRUCTOR_P (fn));
2050 tree parmtype = TREE_VALUE (parmnode);
2053 parmnode = TREE_CHAIN (parmnode);
2055 /* The type of the implicit object parameter ('this') for
2056 overload resolution is not always the same as for the
2057 function itself; conversion functions are considered to
2058 be members of the class being converted, and functions
2059 introduced by a using-declaration are considered to be
2060 members of the class that uses them.
2062 Since build_over_call ignores the ICS for the `this'
2063 parameter, we can just change the parm type. */
2064 if (ctype && is_this)
2066 parmtype = cp_build_qualified_type
2067 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
2068 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn)))
2070 /* If the function has a ref-qualifier, the implicit
2071 object parameter has reference type. */
2072 bool rv = FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn));
2073 parmtype = cp_build_reference_type (parmtype, rv);
2074 /* The special handling of 'this' conversions in compare_ics
2075 does not apply if there is a ref-qualifier. */
2080 parmtype = build_pointer_type (parmtype);
2081 arg = build_this (arg);
2082 argtype = lvalue_type (arg);
2086 /* Core issue 899: When [copy-]initializing a temporary to be bound
2087 to the first parameter of a copy constructor (12.8) called with
2088 a single argument in the context of direct-initialization,
2089 explicit conversion functions are also considered.
2091 So set LOOKUP_COPY_PARM to let reference_binding know that
2092 it's being called in that context. We generalize the above
2093 to handle move constructors and template constructors as well;
2094 the standardese should soon be updated similarly. */
2095 if (ctype && i == 0 && (len-skip == 1)
2096 && DECL_CONSTRUCTOR_P (fn)
2097 && parmtype != error_mark_node
2098 && (same_type_ignoring_top_level_qualifiers_p
2099 (non_reference (parmtype), ctype)))
2101 if (!(flags & LOOKUP_ONLYCONVERTING))
2102 lflags |= LOOKUP_COPY_PARM;
2103 /* We allow user-defined conversions within init-lists, but
2104 don't list-initialize the copy parm, as that would mean
2105 using two levels of braces for the same type. */
2106 if ((flags & LOOKUP_LIST_INIT_CTOR)
2107 && BRACE_ENCLOSED_INITIALIZER_P (arg))
2108 lflags |= LOOKUP_NO_CONVERSION;
2111 lflags |= LOOKUP_ONLYCONVERTING;
2113 t = implicit_conversion (parmtype, argtype, arg,
2114 /*c_cast_p=*/false, lflags, complain);
2119 t = build_identity_conv (argtype, arg);
2120 t->ellipsis_p = true;
2131 reason = arg_conversion_rejection (first_arg, i, argtype, to_type);
2138 reason = bad_arg_conversion_rejection (first_arg, i, arg, to_type);
2143 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
2144 access_path, conversion_path, viable, reason, flags);
2147 /* Create an overload candidate for the conversion function FN which will
2148 be invoked for expression OBJ, producing a pointer-to-function which
2149 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2150 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2151 passed on to implicit_conversion.
2153 Actually, we don't really care about FN; we care about the type it
2154 converts to. There may be multiple conversion functions that will
2155 convert to that type, and we rely on build_user_type_conversion_1 to
2156 choose the best one; so when we create our candidate, we record the type
2157 instead of the function. */
2159 static struct z_candidate *
2160 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
2161 tree first_arg, const vec<tree, va_gc> *arglist,
2162 tree access_path, tree conversion_path,
2163 tsubst_flags_t complain)
2165 tree totype = TREE_TYPE (TREE_TYPE (fn));
2166 int i, len, viable, flags;
2167 tree parmlist, parmnode;
2169 struct rejection_reason *reason;
2171 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
2172 parmlist = TREE_TYPE (parmlist);
2173 parmlist = TYPE_ARG_TYPES (parmlist);
2175 len = vec_safe_length (arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
2176 convs = alloc_conversions (len);
2177 parmnode = parmlist;
2179 flags = LOOKUP_IMPLICIT;
2182 /* Don't bother looking up the same type twice. */
2183 if (*candidates && (*candidates)->fn == totype)
2186 for (i = 0; i < len; ++i)
2188 tree arg, argtype, convert_type = NULL_TREE;
2193 else if (i == 1 && first_arg != NULL_TREE)
2196 arg = (*arglist)[i - (first_arg != NULL_TREE ? 1 : 0) - 1];
2197 argtype = lvalue_type (arg);
2201 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
2203 convert_type = totype;
2205 else if (parmnode == void_list_node)
2209 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
2210 /*c_cast_p=*/false, flags, complain);
2211 convert_type = TREE_VALUE (parmnode);
2215 t = build_identity_conv (argtype, arg);
2216 t->ellipsis_p = true;
2217 convert_type = argtype;
2227 reason = bad_arg_conversion_rejection (NULL_TREE, i, arg, convert_type);
2234 parmnode = TREE_CHAIN (parmnode);
2238 || ! sufficient_parms_p (parmnode))
2240 int remaining = remaining_arguments (parmnode);
2242 reason = arity_rejection (NULL_TREE, i + remaining, len);
2245 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
2246 access_path, conversion_path, viable, reason, flags);
2250 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
2251 tree type1, tree type2, tree *args, tree *argtypes,
2252 int flags, tsubst_flags_t complain)
2259 struct rejection_reason *reason = NULL;
2264 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
2265 convs = alloc_conversions (num_convs);
2267 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2268 conversion ops are allowed. We handle that here by just checking for
2269 boolean_type_node because other operators don't ask for it. COND_EXPR
2270 also does contextual conversion to bool for the first operand, but we
2271 handle that in build_conditional_expr, and type1 here is operand 2. */
2272 if (type1 != boolean_type_node)
2273 flags |= LOOKUP_ONLYCONVERTING;
2275 for (i = 0; i < 2; ++i)
2280 t = implicit_conversion (types[i], argtypes[i], args[i],
2281 /*c_cast_p=*/false, flags, complain);
2285 /* We need something for printing the candidate. */
2286 t = build_identity_conv (types[i], NULL_TREE);
2287 reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i],
2293 reason = bad_arg_conversion_rejection (NULL_TREE, i, args[i],
2299 /* For COND_EXPR we rearranged the arguments; undo that now. */
2302 convs[2] = convs[1];
2303 convs[1] = convs[0];
2304 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
2305 /*c_cast_p=*/false, flags,
2312 reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2],
2317 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
2319 /*access_path=*/NULL_TREE,
2320 /*conversion_path=*/NULL_TREE,
2321 viable, reason, flags);
2325 is_complete (tree t)
2327 return COMPLETE_TYPE_P (complete_type (t));
2330 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2333 promoted_arithmetic_type_p (tree type)
2337 In this section, the term promoted integral type is used to refer
2338 to those integral types which are preserved by integral promotion
2339 (including e.g. int and long but excluding e.g. char).
2340 Similarly, the term promoted arithmetic type refers to promoted
2341 integral types plus floating types. */
2342 return ((CP_INTEGRAL_TYPE_P (type)
2343 && same_type_p (type_promotes_to (type), type))
2344 || TREE_CODE (type) == REAL_TYPE);
2347 /* Create any builtin operator overload candidates for the operator in
2348 question given the converted operand types TYPE1 and TYPE2. The other
2349 args are passed through from add_builtin_candidates to
2350 build_builtin_candidate.
2352 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2353 If CODE is requires candidates operands of the same type of the kind
2354 of which TYPE1 and TYPE2 are, we add both candidates
2355 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2358 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
2359 enum tree_code code2, tree fnname, tree type1,
2360 tree type2, tree *args, tree *argtypes, int flags,
2361 tsubst_flags_t complain)
2365 case POSTINCREMENT_EXPR:
2366 case POSTDECREMENT_EXPR:
2367 args[1] = integer_zero_node;
2368 type2 = integer_type_node;
2377 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2378 and VQ is either volatile or empty, there exist candidate operator
2379 functions of the form
2380 VQ T& operator++(VQ T&);
2381 T operator++(VQ T&, int);
2382 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2383 type other than bool, and VQ is either volatile or empty, there exist
2384 candidate operator functions of the form
2385 VQ T& operator--(VQ T&);
2386 T operator--(VQ T&, int);
2387 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2388 complete object type, and VQ is either volatile or empty, there exist
2389 candidate operator functions of the form
2390 T*VQ& operator++(T*VQ&);
2391 T*VQ& operator--(T*VQ&);
2392 T* operator++(T*VQ&, int);
2393 T* operator--(T*VQ&, int); */
2395 case POSTDECREMENT_EXPR:
2396 case PREDECREMENT_EXPR:
2397 if (TREE_CODE (type1) == BOOLEAN_TYPE)
2399 case POSTINCREMENT_EXPR:
2400 case PREINCREMENT_EXPR:
2401 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
2403 type1 = build_reference_type (type1);
2408 /* 7 For every cv-qualified or cv-unqualified object type T, there
2409 exist candidate operator functions of the form
2413 8 For every function type T, there exist candidate operator functions of
2415 T& operator*(T*); */
2418 if (TYPE_PTR_P (type1)
2419 && (TYPE_PTROB_P (type1)
2420 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
2424 /* 9 For every type T, there exist candidate operator functions of the form
2427 10For every promoted arithmetic type T, there exist candidate operator
2428 functions of the form
2432 case UNARY_PLUS_EXPR: /* unary + */
2433 if (TYPE_PTR_P (type1))
2436 if (ARITHMETIC_TYPE_P (type1))
2440 /* 11For every promoted integral type T, there exist candidate operator
2441 functions of the form
2445 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2449 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2450 is the same type as C2 or is a derived class of C2, T is a complete
2451 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2452 there exist candidate operator functions of the form
2453 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2454 where CV12 is the union of CV1 and CV2. */
2457 if (TYPE_PTR_P (type1) && TYPE_PTRMEM_P (type2))
2459 tree c1 = TREE_TYPE (type1);
2460 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2462 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2463 && (TYPE_PTRMEMFUNC_P (type2)
2464 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2469 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2470 didate operator functions of the form
2475 bool operator<(L, R);
2476 bool operator>(L, R);
2477 bool operator<=(L, R);
2478 bool operator>=(L, R);
2479 bool operator==(L, R);
2480 bool operator!=(L, R);
2481 where LR is the result of the usual arithmetic conversions between
2484 14For every pair of types T and I, where T is a cv-qualified or cv-
2485 unqualified complete object type and I is a promoted integral type,
2486 there exist candidate operator functions of the form
2487 T* operator+(T*, I);
2488 T& operator[](T*, I);
2489 T* operator-(T*, I);
2490 T* operator+(I, T*);
2491 T& operator[](I, T*);
2493 15For every T, where T is a pointer to complete object type, there exist
2494 candidate operator functions of the form112)
2495 ptrdiff_t operator-(T, T);
2497 16For every pointer or enumeration type T, there exist candidate operator
2498 functions of the form
2499 bool operator<(T, T);
2500 bool operator>(T, T);
2501 bool operator<=(T, T);
2502 bool operator>=(T, T);
2503 bool operator==(T, T);
2504 bool operator!=(T, T);
2506 17For every pointer to member type T, there exist candidate operator
2507 functions of the form
2508 bool operator==(T, T);
2509 bool operator!=(T, T); */
2512 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2514 if (TYPE_PTROB_P (type1)
2515 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2517 type2 = ptrdiff_type_node;
2521 case TRUNC_DIV_EXPR:
2522 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2528 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2529 || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2)))
2531 if (TYPE_PTRMEM_P (type1) && null_ptr_cst_p (args[1]))
2536 if (TYPE_PTRMEM_P (type2) && null_ptr_cst_p (args[0]))
2548 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2550 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2552 if (TREE_CODE (type1) == ENUMERAL_TYPE
2553 && TREE_CODE (type2) == ENUMERAL_TYPE)
2555 if (TYPE_PTR_P (type1)
2556 && null_ptr_cst_p (args[1]))
2561 if (null_ptr_cst_p (args[0])
2562 && TYPE_PTR_P (type2))
2570 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2573 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2575 type1 = ptrdiff_type_node;
2578 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2580 type2 = ptrdiff_type_node;
2585 /* 18For every pair of promoted integral types L and R, there exist candi-
2586 date operator functions of the form
2593 where LR is the result of the usual arithmetic conversions between
2596 case TRUNC_MOD_EXPR:
2602 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2606 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2607 type, VQ is either volatile or empty, and R is a promoted arithmetic
2608 type, there exist candidate operator functions of the form
2609 VQ L& operator=(VQ L&, R);
2610 VQ L& operator*=(VQ L&, R);
2611 VQ L& operator/=(VQ L&, R);
2612 VQ L& operator+=(VQ L&, R);
2613 VQ L& operator-=(VQ L&, R);
2615 20For every pair T, VQ), where T is any type and VQ is either volatile
2616 or empty, there exist candidate operator functions of the form
2617 T*VQ& operator=(T*VQ&, T*);
2619 21For every pair T, VQ), where T is a pointer to member type and VQ is
2620 either volatile or empty, there exist candidate operator functions of
2622 VQ T& operator=(VQ T&, T);
2624 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2625 unqualified complete object type, VQ is either volatile or empty, and
2626 I is a promoted integral type, there exist candidate operator func-
2628 T*VQ& operator+=(T*VQ&, I);
2629 T*VQ& operator-=(T*VQ&, I);
2631 23For every triple L, VQ, R), where L is an integral or enumeration
2632 type, VQ is either volatile or empty, and R is a promoted integral
2633 type, there exist candidate operator functions of the form
2635 VQ L& operator%=(VQ L&, R);
2636 VQ L& operator<<=(VQ L&, R);
2637 VQ L& operator>>=(VQ L&, R);
2638 VQ L& operator&=(VQ L&, R);
2639 VQ L& operator^=(VQ L&, R);
2640 VQ L& operator|=(VQ L&, R); */
2647 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2649 type2 = ptrdiff_type_node;
2653 case TRUNC_DIV_EXPR:
2654 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2658 case TRUNC_MOD_EXPR:
2664 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2669 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2671 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2672 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2673 || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2))
2674 || ((TYPE_PTRMEMFUNC_P (type1)
2675 || TYPE_PTR_P (type1))
2676 && null_ptr_cst_p (args[1])))
2686 type1 = build_reference_type (type1);
2692 For every pair of promoted arithmetic types L and R, there
2693 exist candidate operator functions of the form
2695 LR operator?(bool, L, R);
2697 where LR is the result of the usual arithmetic conversions
2698 between types L and R.
2700 For every type T, where T is a pointer or pointer-to-member
2701 type, there exist candidate operator functions of the form T
2702 operator?(bool, T, T); */
2704 if (promoted_arithmetic_type_p (type1)
2705 && promoted_arithmetic_type_p (type2))
2709 /* Otherwise, the types should be pointers. */
2710 if (!TYPE_PTR_OR_PTRMEM_P (type1) || !TYPE_PTR_OR_PTRMEM_P (type2))
2713 /* We don't check that the two types are the same; the logic
2714 below will actually create two candidates; one in which both
2715 parameter types are TYPE1, and one in which both parameter
2721 if (ARITHMETIC_TYPE_P (type1))
2729 /* Make sure we don't create builtin candidates with dependent types. */
2730 bool u1 = uses_template_parms (type1);
2731 bool u2 = type2 ? uses_template_parms (type2) : false;
2734 /* Try to recover if one of the types is non-dependent. But if
2735 there's only one type, there's nothing we can do. */
2738 /* And we lose if both are dependent. */
2741 /* Or if they have different forms. */
2742 if (TREE_CODE (type1) != TREE_CODE (type2))
2751 /* If we're dealing with two pointer types or two enumeral types,
2752 we need candidates for both of them. */
2753 if (type2 && !same_type_p (type1, type2)
2754 && TREE_CODE (type1) == TREE_CODE (type2)
2755 && (TREE_CODE (type1) == REFERENCE_TYPE
2756 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2757 || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2))
2758 || TYPE_PTRMEMFUNC_P (type1)
2759 || MAYBE_CLASS_TYPE_P (type1)
2760 || TREE_CODE (type1) == ENUMERAL_TYPE))
2762 if (TYPE_PTR_OR_PTRMEM_P (type1))
2764 tree cptype = composite_pointer_type (type1, type2,
2769 if (cptype != error_mark_node)
2771 build_builtin_candidate
2772 (candidates, fnname, cptype, cptype, args, argtypes,
2778 build_builtin_candidate
2779 (candidates, fnname, type1, type1, args, argtypes, flags, complain);
2780 build_builtin_candidate
2781 (candidates, fnname, type2, type2, args, argtypes, flags, complain);
2785 build_builtin_candidate
2786 (candidates, fnname, type1, type2, args, argtypes, flags, complain);
2790 type_decays_to (tree type)
2792 if (TREE_CODE (type) == ARRAY_TYPE)
2793 return build_pointer_type (TREE_TYPE (type));
2794 if (TREE_CODE (type) == FUNCTION_TYPE)
2795 return build_pointer_type (type);
2799 /* There are three conditions of builtin candidates:
2801 1) bool-taking candidates. These are the same regardless of the input.
2802 2) pointer-pair taking candidates. These are generated for each type
2803 one of the input types converts to.
2804 3) arithmetic candidates. According to the standard, we should generate
2805 all of these, but I'm trying not to...
2807 Here we generate a superset of the possible candidates for this particular
2808 case. That is a subset of the full set the standard defines, plus some
2809 other cases which the standard disallows. add_builtin_candidate will
2810 filter out the invalid set. */
2813 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2814 enum tree_code code2, tree fnname, tree *args,
2815 int flags, tsubst_flags_t complain)
2819 tree type, argtypes[3], t;
2820 /* TYPES[i] is the set of possible builtin-operator parameter types
2821 we will consider for the Ith argument. */
2822 vec<tree, va_gc> *types[2];
2825 for (i = 0; i < 3; ++i)
2828 argtypes[i] = unlowered_expr_type (args[i]);
2830 argtypes[i] = NULL_TREE;
2835 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2836 and VQ is either volatile or empty, there exist candidate operator
2837 functions of the form
2838 VQ T& operator++(VQ T&); */
2840 case POSTINCREMENT_EXPR:
2841 case PREINCREMENT_EXPR:
2842 case POSTDECREMENT_EXPR:
2843 case PREDECREMENT_EXPR:
2848 /* 24There also exist candidate operator functions of the form
2849 bool operator!(bool);
2850 bool operator&&(bool, bool);
2851 bool operator||(bool, bool); */
2853 case TRUTH_NOT_EXPR:
2854 build_builtin_candidate
2855 (candidates, fnname, boolean_type_node,
2856 NULL_TREE, args, argtypes, flags, complain);
2859 case TRUTH_ORIF_EXPR:
2860 case TRUTH_ANDIF_EXPR:
2861 build_builtin_candidate
2862 (candidates, fnname, boolean_type_node,
2863 boolean_type_node, args, argtypes, flags, complain);
2885 types[0] = make_tree_vector ();
2886 types[1] = make_tree_vector ();
2888 for (i = 0; i < 2; ++i)
2892 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2896 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2899 convs = lookup_conversions (argtypes[i]);
2901 if (code == COND_EXPR)
2903 if (real_lvalue_p (args[i]))
2904 vec_safe_push (types[i], build_reference_type (argtypes[i]));
2906 vec_safe_push (types[i], TYPE_MAIN_VARIANT (argtypes[i]));
2912 for (; convs; convs = TREE_CHAIN (convs))
2914 type = TREE_TYPE (convs);
2917 && (TREE_CODE (type) != REFERENCE_TYPE
2918 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2921 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2922 vec_safe_push (types[i], type);
2924 type = non_reference (type);
2925 if (i != 0 || ! ref1)
2927 type = cv_unqualified (type_decays_to (type));
2928 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2929 vec_safe_push (types[i], type);
2930 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2931 type = type_promotes_to (type);
2934 if (! vec_member (type, types[i]))
2935 vec_safe_push (types[i], type);
2940 if (code == COND_EXPR && real_lvalue_p (args[i]))
2941 vec_safe_push (types[i], build_reference_type (argtypes[i]));
2942 type = non_reference (argtypes[i]);
2943 if (i != 0 || ! ref1)
2945 type = cv_unqualified (type_decays_to (type));
2946 if (enum_p && UNSCOPED_ENUM_P (type))
2947 vec_safe_push (types[i], type);
2948 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2949 type = type_promotes_to (type);
2951 vec_safe_push (types[i], type);
2955 /* Run through the possible parameter types of both arguments,
2956 creating candidates with those parameter types. */
2957 FOR_EACH_VEC_ELT_REVERSE (*(types[0]), ix, t)
2962 if (!types[1]->is_empty ())
2963 FOR_EACH_VEC_ELT_REVERSE (*(types[1]), jx, u)
2964 add_builtin_candidate
2965 (candidates, code, code2, fnname, t,
2966 u, args, argtypes, flags, complain);
2968 add_builtin_candidate
2969 (candidates, code, code2, fnname, t,
2970 NULL_TREE, args, argtypes, flags, complain);
2973 release_tree_vector (types[0]);
2974 release_tree_vector (types[1]);
2978 /* If TMPL can be successfully instantiated as indicated by
2979 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2981 TMPL is the template. EXPLICIT_TARGS are any explicit template
2982 arguments. ARGLIST is the arguments provided at the call-site.
2983 This does not change ARGLIST. The RETURN_TYPE is the desired type
2984 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2985 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2986 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2988 static struct z_candidate*
2989 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2990 tree ctype, tree explicit_targs, tree first_arg,
2991 const vec<tree, va_gc> *arglist, tree return_type,
2992 tree access_path, tree conversion_path,
2993 int flags, tree obj, unification_kind_t strict,
2994 tsubst_flags_t complain)
2996 int ntparms = DECL_NTPARMS (tmpl);
2997 tree targs = make_tree_vec (ntparms);
2998 unsigned int len = vec_safe_length (arglist);
2999 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
3000 unsigned int skip_without_in_chrg = 0;
3001 tree first_arg_without_in_chrg = first_arg;
3002 tree *args_without_in_chrg;
3003 unsigned int nargs_without_in_chrg;
3004 unsigned int ia, ix;
3006 struct z_candidate *cand;
3008 struct rejection_reason *reason = NULL;
3011 /* We don't do deduction on the in-charge parameter, the VTT
3012 parameter or 'this'. */
3013 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
3015 if (first_arg_without_in_chrg != NULL_TREE)
3016 first_arg_without_in_chrg = NULL_TREE;
3018 ++skip_without_in_chrg;
3021 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
3022 || DECL_BASE_CONSTRUCTOR_P (tmpl))
3023 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
3025 if (first_arg_without_in_chrg != NULL_TREE)
3026 first_arg_without_in_chrg = NULL_TREE;
3028 ++skip_without_in_chrg;
3031 if (len < skip_without_in_chrg)
3034 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
3035 + (len - skip_without_in_chrg));
3036 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
3038 if (first_arg_without_in_chrg != NULL_TREE)
3040 args_without_in_chrg[ia] = first_arg_without_in_chrg;
3043 for (ix = skip_without_in_chrg;
3044 vec_safe_iterate (arglist, ix, &arg);
3047 args_without_in_chrg[ia] = arg;
3050 gcc_assert (ia == nargs_without_in_chrg);
3052 errs = errorcount+sorrycount;
3053 fn = fn_type_unification (tmpl, explicit_targs, targs,
3054 args_without_in_chrg,
3055 nargs_without_in_chrg,
3056 return_type, strict, flags, false,
3057 complain & tf_decltype);
3059 if (fn == error_mark_node)
3061 /* Don't repeat unification later if it already resulted in errors. */
3062 if (errorcount+sorrycount == errs)
3063 reason = template_unification_rejection (tmpl, explicit_targs,
3064 targs, args_without_in_chrg,
3065 nargs_without_in_chrg,
3066 return_type, strict, flags);
3068 reason = template_unification_error_rejection ();
3074 A member function template is never instantiated to perform the
3075 copy of a class object to an object of its class type.
3077 It's a little unclear what this means; the standard explicitly
3078 does allow a template to be used to copy a class. For example,
3083 template <class T> A(const T&);
3086 void g () { A a (f ()); }
3088 the member template will be used to make the copy. The section
3089 quoted above appears in the paragraph that forbids constructors
3090 whose only parameter is (a possibly cv-qualified variant of) the
3091 class type, and a logical interpretation is that the intent was
3092 to forbid the instantiation of member templates which would then
3094 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
3096 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
3097 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
3100 reason = invalid_copy_with_fn_template_rejection ();
3105 if (obj != NULL_TREE)
3106 /* Aha, this is a conversion function. */
3107 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
3108 access_path, conversion_path, complain);
3110 cand = add_function_candidate (candidates, fn, ctype,
3111 first_arg, arglist, access_path,
3112 conversion_path, flags, complain);
3113 if (DECL_TI_TEMPLATE (fn) != tmpl)
3114 /* This situation can occur if a member template of a template
3115 class is specialized. Then, instantiate_template might return
3116 an instantiation of the specialization, in which case the
3117 DECL_TI_TEMPLATE field will point at the original
3118 specialization. For example:
3120 template <class T> struct S { template <class U> void f(U);
3121 template <> void f(int) {}; };
3125 Here, TMPL will be template <class U> S<double>::f(U).
3126 And, instantiate template will give us the specialization
3127 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3128 for this will point at template <class T> template <> S<T>::f(int),
3129 so that we can find the definition. For the purposes of
3130 overload resolution, however, we want the original TMPL. */
3131 cand->template_decl = build_template_info (tmpl, targs);
3133 cand->template_decl = DECL_TEMPLATE_INFO (fn);
3134 cand->explicit_targs = explicit_targs;
3138 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
3139 access_path, conversion_path, 0, reason, flags);
3143 static struct z_candidate *
3144 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
3145 tree explicit_targs, tree first_arg,
3146 const vec<tree, va_gc> *arglist, tree return_type,
3147 tree access_path, tree conversion_path, int flags,
3148 unification_kind_t strict, tsubst_flags_t complain)
3151 add_template_candidate_real (candidates, tmpl, ctype,
3152 explicit_targs, first_arg, arglist,
3153 return_type, access_path, conversion_path,
3154 flags, NULL_TREE, strict, complain);
3158 static struct z_candidate *
3159 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
3160 tree obj, tree first_arg,
3161 const vec<tree, va_gc> *arglist,
3162 tree return_type, tree access_path,
3163 tree conversion_path, tsubst_flags_t complain)
3166 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
3167 first_arg, arglist, return_type, access_path,
3168 conversion_path, 0, obj, DEDUCE_CONV,
3172 /* The CANDS are the set of candidates that were considered for
3173 overload resolution. Return the set of viable candidates, or CANDS
3174 if none are viable. If any of the candidates were viable, set
3175 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3176 considered viable only if it is strictly viable. */
3178 static struct z_candidate*
3179 splice_viable (struct z_candidate *cands,
3183 struct z_candidate *viable;
3184 struct z_candidate **last_viable;
3185 struct z_candidate **cand;
3186 bool found_strictly_viable = false;
3188 /* Be strict inside templates, since build_over_call won't actually
3189 do the conversions to get pedwarns. */
3190 if (processing_template_decl)
3194 last_viable = &viable;
3195 *any_viable_p = false;
3200 struct z_candidate *c = *cand;
3202 && (c->viable == 1 || TREE_CODE (c->fn) == TEMPLATE_DECL))
3204 /* Be strict in the presence of a viable candidate. Also if
3205 there are template candidates, so that we get deduction errors
3206 for them instead of silently preferring a bad conversion. */
3208 if (viable && !found_strictly_viable)
3210 /* Put any spliced near matches back onto the main list so
3211 that we see them if there is no strict match. */
3212 *any_viable_p = false;
3213 *last_viable = cands;
3216 last_viable = &viable;
3220 if (strict_p ? c->viable == 1 : c->viable)
3225 last_viable = &c->next;
3226 *any_viable_p = true;
3228 found_strictly_viable = true;
3234 return viable ? viable : cands;
3238 any_strictly_viable (struct z_candidate *cands)
3240 for (; cands; cands = cands->next)
3241 if (cands->viable == 1)
3246 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3247 words, it is about to become the "this" pointer for a member
3248 function call. Take the address of the object. */
3251 build_this (tree obj)
3253 /* In a template, we are only concerned about the type of the
3254 expression, so we can take a shortcut. */
3255 if (processing_template_decl)
3256 return build_address (obj);
3258 return cp_build_addr_expr (obj, tf_warning_or_error);
3261 /* Returns true iff functions are equivalent. Equivalent functions are
3262 not '==' only if one is a function-local extern function or if
3263 both are extern "C". */
3266 equal_functions (tree fn1, tree fn2)
3268 if (TREE_CODE (fn1) != TREE_CODE (fn2))
3270 if (TREE_CODE (fn1) == TEMPLATE_DECL)
3272 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
3273 || DECL_EXTERN_C_FUNCTION_P (fn1))
3274 return decls_match (fn1, fn2);
3278 /* Print information about a candidate being rejected due to INFO. */
3281 print_conversion_rejection (location_t loc, struct conversion_info *info)
3283 tree from = info->from;
3285 from = lvalue_type (from);
3286 if (info->n_arg == -1)
3288 /* Conversion of implicit `this' argument failed. */
3289 if (!TYPE_P (info->from))
3290 /* A bad conversion for 'this' must be discarding cv-quals. */
3291 inform (loc, " passing %qT as %<this%> "
3292 "argument discards qualifiers",
3295 inform (loc, " no known conversion for implicit "
3296 "%<this%> parameter from %qT to %qT",
3297 from, info->to_type);
3299 else if (!TYPE_P (info->from))
3301 if (info->n_arg >= 0)
3302 inform (loc, " conversion of argument %d would be ill-formed:",
3304 perform_implicit_conversion (info->to_type, info->from,
3305 tf_warning_or_error);
3307 else if (info->n_arg == -2)
3308 /* Conversion of conversion function return value failed. */
3309 inform (loc, " no known conversion from %qT to %qT",
3310 from, info->to_type);
3312 inform (loc, " no known conversion for argument %d from %qT to %qT",
3313 info->n_arg + 1, from, info->to_type);
3316 /* Print information about a candidate with WANT parameters and we found
3320 print_arity_information (location_t loc, unsigned int have, unsigned int want)
3322 inform_n (loc, want,
3323 " candidate expects %d argument, %d provided",
3324 " candidate expects %d arguments, %d provided",
3328 /* Print information about one overload candidate CANDIDATE. MSGSTR
3329 is the text to print before the candidate itself.
3331 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3332 to have been run through gettext by the caller. This wart makes
3333 life simpler in print_z_candidates and for the translators. */
3336 print_z_candidate (location_t loc, const char *msgstr,
3337 struct z_candidate *candidate)
3339 const char *msg = (msgstr == NULL
3341 : ACONCAT ((msgstr, " ", NULL)));
3342 location_t cloc = location_of (candidate->fn);
3344 if (identifier_p (candidate->fn))
3347 if (candidate->num_convs == 3)
3348 inform (cloc, "%s%D(%T, %T, %T) <built-in>", msg, candidate->fn,
3349 candidate->convs[0]->type,
3350 candidate->convs[1]->type,
3351 candidate->convs[2]->type);
3352 else if (candidate->num_convs == 2)
3353 inform (cloc, "%s%D(%T, %T) <built-in>", msg, candidate->fn,
3354 candidate->convs[0]->type,
3355 candidate->convs[1]->type);
3357 inform (cloc, "%s%D(%T) <built-in>", msg, candidate->fn,
3358 candidate->convs[0]->type);
3360 else if (TYPE_P (candidate->fn))
3361 inform (cloc, "%s%T <conversion>", msg, candidate->fn);
3362 else if (candidate->viable == -1)
3363 inform (cloc, "%s%#D <near match>", msg, candidate->fn);
3364 else if (DECL_DELETED_FN (candidate->fn))
3365 inform (cloc, "%s%#D <deleted>", msg, candidate->fn);
3367 inform (cloc, "%s%#D", msg, candidate->fn);
3368 /* Give the user some information about why this candidate failed. */
3369 if (candidate->reason != NULL)
3371 struct rejection_reason *r = candidate->reason;
3376 print_arity_information (cloc, r->u.arity.actual,
3377 r->u.arity.expected);
3379 case rr_arg_conversion:
3380 print_conversion_rejection (cloc, &r->u.conversion);
3382 case rr_bad_arg_conversion:
3383 print_conversion_rejection (cloc, &r->u.bad_conversion);
3385 case rr_explicit_conversion:
3386 inform (cloc, " return type %qT of explicit conversion function "
3387 "cannot be converted to %qT with a qualification "
3388 "conversion", r->u.conversion.from,
3389 r->u.conversion.to_type);
3391 case rr_template_conversion:
3392 inform (cloc, " conversion from return type %qT of template "
3393 "conversion function specialization to %qT is not an "
3394 "exact match", r->u.conversion.from,
3395 r->u.conversion.to_type);
3397 case rr_template_unification:
3398 /* We use template_unification_error_rejection if unification caused
3399 actual non-SFINAE errors, in which case we don't need to repeat
3401 if (r->u.template_unification.tmpl == NULL_TREE)
3403 inform (cloc, " substitution of deduced template arguments "
3404 "resulted in errors seen above");
3407 /* Re-run template unification with diagnostics. */
3408 inform (cloc, " template argument deduction/substitution failed:");
3409 fn_type_unification (r->u.template_unification.tmpl,
3410 r->u.template_unification.explicit_targs,
3412 (r->u.template_unification.num_targs)),
3413 r->u.template_unification.args,
3414 r->u.template_unification.nargs,
3415 r->u.template_unification.return_type,
3416 r->u.template_unification.strict,
3417 r->u.template_unification.flags,
3420 case rr_invalid_copy:
3422 " a constructor taking a single argument of its own "
3423 "class type is invalid");
3427 /* This candidate didn't have any issues or we failed to
3428 handle a particular code. Either way... */
3435 print_z_candidates (location_t loc, struct z_candidate *candidates)
3437 struct z_candidate *cand1;
3438 struct z_candidate **cand2;
3444 /* Remove non-viable deleted candidates. */
3446 for (cand2 = &cand1; *cand2; )
3448 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
3449 && !(*cand2)->viable
3450 && DECL_DELETED_FN ((*cand2)->fn))
3451 *cand2 = (*cand2)->next;
3453 cand2 = &(*cand2)->next;
3455 /* ...if there are any non-deleted ones. */
3459 /* There may be duplicates in the set of candidates. We put off
3460 checking this condition as long as possible, since we have no way
3461 to eliminate duplicates from a set of functions in less than n^2
3462 time. Now we are about to emit an error message, so it is more
3463 permissible to go slowly. */
3464 for (cand1 = candidates; cand1; cand1 = cand1->next)
3466 tree fn = cand1->fn;
3467 /* Skip builtin candidates and conversion functions. */
3470 cand2 = &cand1->next;
3473 if (DECL_P ((*cand2)->fn)
3474 && equal_functions (fn, (*cand2)->fn))
3475 *cand2 = (*cand2)->next;
3477 cand2 = &(*cand2)->next;
3481 for (n_candidates = 0, cand1 = candidates; cand1; cand1 = cand1->next)
3484 for (; candidates; candidates = candidates->next)
3485 print_z_candidate (loc, "candidate:", candidates);
3488 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3489 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3490 the result of the conversion function to convert it to the final
3491 desired type. Merge the two sequences into a single sequence,
3492 and return the merged sequence. */
3495 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
3498 bool bad = user_seq->bad_p;
3500 gcc_assert (user_seq->kind == ck_user);
3502 /* Find the end of the second conversion sequence. */
3503 for (t = &std_seq; (*t)->kind != ck_identity; t = &((*t)->u.next))
3505 /* The entire sequence is a user-conversion sequence. */
3506 (*t)->user_conv_p = true;
3511 /* Replace the identity conversion with the user conversion
3518 /* Handle overload resolution for initializing an object of class type from
3519 an initializer list. First we look for a suitable constructor that
3520 takes a std::initializer_list; if we don't find one, we then look for a
3521 non-list constructor.
3523 Parameters are as for add_candidates, except that the arguments are in
3524 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3525 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3528 add_list_candidates (tree fns, tree first_arg,
3529 tree init_list, tree totype,
3530 tree explicit_targs, bool template_only,
3531 tree conversion_path, tree access_path,
3533 struct z_candidate **candidates,
3534 tsubst_flags_t complain)
3536 vec<tree, va_gc> *args;
3538 gcc_assert (*candidates == NULL);
3540 /* We're looking for a ctor for list-initialization. */
3541 flags |= LOOKUP_LIST_INIT_CTOR;
3542 /* And we don't allow narrowing conversions. We also use this flag to
3543 avoid the copy constructor call for copy-list-initialization. */
3544 flags |= LOOKUP_NO_NARROWING;
3546 /* Always use the default constructor if the list is empty (DR 990). */
3547 if (CONSTRUCTOR_NELTS (init_list) == 0
3548 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
3550 /* If the class has a list ctor, try passing the list as a single
3551 argument first, but only consider list ctors. */
3552 else if (TYPE_HAS_LIST_CTOR (totype))
3554 flags |= LOOKUP_LIST_ONLY;
3555 args = make_tree_vector_single (init_list);
3556 add_candidates (fns, first_arg, args, NULL_TREE,
3557 explicit_targs, template_only, conversion_path,
3558 access_path, flags, candidates, complain);
3559 if (any_strictly_viable (*candidates))
3563 args = ctor_to_vec (init_list);
3565 /* We aren't looking for list-ctors anymore. */
3566 flags &= ~LOOKUP_LIST_ONLY;
3567 /* We allow more user-defined conversions within an init-list. */
3568 flags &= ~LOOKUP_NO_CONVERSION;
3570 add_candidates (fns, first_arg, args, NULL_TREE,
3571 explicit_targs, template_only, conversion_path,
3572 access_path, flags, candidates, complain);
3575 /* Returns the best overload candidate to perform the requested
3576 conversion. This function is used for three the overloading situations
3577 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3578 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3579 per [dcl.init.ref], so we ignore temporary bindings. */
3581 static struct z_candidate *
3582 build_user_type_conversion_1 (tree totype, tree expr, int flags,
3583 tsubst_flags_t complain)
3585 struct z_candidate *candidates, *cand;
3587 tree ctors = NULL_TREE;
3588 tree conv_fns = NULL_TREE;
3589 conversion *conv = NULL;
3590 tree first_arg = NULL_TREE;
3591 vec<tree, va_gc> *args = NULL;
3598 fromtype = TREE_TYPE (expr);
3600 /* We represent conversion within a hierarchy using RVALUE_CONV and
3601 BASE_CONV, as specified by [over.best.ics]; these become plain
3602 constructor calls, as specified in [dcl.init]. */
3603 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
3604 || !DERIVED_FROM_P (totype, fromtype));
3606 if (MAYBE_CLASS_TYPE_P (totype))
3607 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3608 creating a garbage BASELINK; constructors can't be inherited. */
3609 ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
3611 if (MAYBE_CLASS_TYPE_P (fromtype))
3613 tree to_nonref = non_reference (totype);
3614 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
3615 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
3616 && DERIVED_FROM_P (to_nonref, fromtype)))
3618 /* [class.conv.fct] A conversion function is never used to
3619 convert a (possibly cv-qualified) object to the (possibly
3620 cv-qualified) same object type (or a reference to it), to a
3621 (possibly cv-qualified) base class of that type (or a
3622 reference to it)... */
3625 conv_fns = lookup_conversions (fromtype);
3629 flags |= LOOKUP_NO_CONVERSION;
3630 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3631 flags |= LOOKUP_NO_NARROWING;
3633 /* It's OK to bind a temporary for converting constructor arguments, but
3634 not in converting the return value of a conversion operator. */
3635 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION
3636 | (flags & LOOKUP_NO_NARROWING));
3637 flags &= ~LOOKUP_NO_TEMP_BIND;
3641 int ctorflags = flags;
3643 first_arg = build_dummy_object (totype);
3645 /* We should never try to call the abstract or base constructor
3647 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3648 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3650 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3652 /* List-initialization. */
3653 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3654 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3655 ctorflags, &candidates, complain);
3659 args = make_tree_vector_single (expr);
3660 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3661 TYPE_BINFO (totype), TYPE_BINFO (totype),
3662 ctorflags, &candidates, complain);
3665 for (cand = candidates; cand; cand = cand->next)
3667 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3669 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3670 set, then this is copy-initialization. In that case, "The
3671 result of the call is then used to direct-initialize the
3672 object that is the destination of the copy-initialization."
3675 We represent this in the conversion sequence with an
3676 rvalue conversion, which means a constructor call. */
3677 if (TREE_CODE (totype) != REFERENCE_TYPE
3678 && !(convflags & LOOKUP_NO_TEMP_BIND))
3680 = build_conv (ck_rvalue, totype, cand->second_conv);
3687 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3689 tree conversion_path = TREE_PURPOSE (conv_fns);
3690 struct z_candidate *old_candidates;
3692 /* If we are called to convert to a reference type, we are trying to
3693 find a direct binding, so don't even consider temporaries. If
3694 we don't find a direct binding, the caller will try again to
3695 look for a temporary binding. */
3696 if (TREE_CODE (totype) == REFERENCE_TYPE)
3697 convflags |= LOOKUP_NO_TEMP_BIND;
3699 old_candidates = candidates;
3700 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3702 conversion_path, TYPE_BINFO (fromtype),
3703 flags, &candidates, complain);
3705 for (cand = candidates; cand != old_candidates; cand = cand->next)
3707 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3709 = implicit_conversion (totype,
3712 /*c_cast_p=*/false, convflags,
3715 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3716 copy-initialization. In that case, "The result of the
3717 call is then used to direct-initialize the object that is
3718 the destination of the copy-initialization." [dcl.init]
3720 We represent this in the conversion sequence with an
3721 rvalue conversion, which means a constructor call. But
3722 don't add a second rvalue conversion if there's already
3723 one there. Which there really shouldn't be, but it's
3724 harmless since we'd add it here anyway. */
3725 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3726 && !(convflags & LOOKUP_NO_TEMP_BIND))
3727 ics = build_conv (ck_rvalue, totype, ics);
3729 cand->second_conv = ics;
3734 cand->reason = arg_conversion_rejection (NULL_TREE, -2,
3737 else if (DECL_NONCONVERTING_P (cand->fn)
3738 && ics->rank > cr_exact)
3740 /* 13.3.1.5: For direct-initialization, those explicit
3741 conversion functions that are not hidden within S and
3742 yield type T or a type that can be converted to type T
3743 with a qualification conversion (4.4) are also candidate
3745 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3746 I've raised this issue with the committee. --jason 9/2011 */
3748 cand->reason = explicit_conversion_rejection (rettype, totype);
3750 else if (cand->viable == 1 && ics->bad_p)
3754 = bad_arg_conversion_rejection (NULL_TREE, -2,
3757 else if (primary_template_instantiation_p (cand->fn)
3758 && ics->rank > cr_exact)
3760 /* 13.3.3.1.2: If the user-defined conversion is specified by
3761 a specialization of a conversion function template, the
3762 second standard conversion sequence shall have exact match
3765 cand->reason = template_conversion_rejection (rettype, totype);
3770 candidates = splice_viable (candidates, false, &any_viable_p);
3774 release_tree_vector (args);
3778 cand = tourney (candidates, complain);
3781 if (complain & tf_error)
3783 error ("conversion from %qT to %qT is ambiguous",
3785 print_z_candidates (location_of (expr), candidates);
3788 cand = candidates; /* any one will do */
3789 cand->second_conv = build_ambiguous_conv (totype, expr);
3790 cand->second_conv->user_conv_p = true;
3791 if (!any_strictly_viable (candidates))
3792 cand->second_conv->bad_p = true;
3793 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3794 ambiguous conversion is no worse than another user-defined
3801 if (!DECL_CONSTRUCTOR_P (cand->fn))
3802 convtype = non_reference (TREE_TYPE (TREE_TYPE (cand->fn)));
3803 else if (cand->second_conv->kind == ck_rvalue)
3804 /* DR 5: [in the first step of copy-initialization]...if the function
3805 is a constructor, the call initializes a temporary of the
3806 cv-unqualified version of the destination type. */
3807 convtype = cv_unqualified (totype);
3810 /* Build the user conversion sequence. */
3814 build_identity_conv (TREE_TYPE (expr), expr));
3816 if (cand->viable == -1)
3819 /* Remember that this was a list-initialization. */
3820 if (flags & LOOKUP_NO_NARROWING)
3821 conv->check_narrowing = true;
3823 /* Combine it with the second conversion sequence. */
3824 cand->second_conv = merge_conversion_sequences (conv,
3830 /* Wrapper for above. */
3833 build_user_type_conversion (tree totype, tree expr, int flags,
3834 tsubst_flags_t complain)
3836 struct z_candidate *cand;
3839 bool subtime = timevar_cond_start (TV_OVERLOAD);
3840 cand = build_user_type_conversion_1 (totype, expr, flags, complain);
3844 if (cand->second_conv->kind == ck_ambig)
3845 ret = error_mark_node;
3848 expr = convert_like (cand->second_conv, expr, complain);
3849 ret = convert_from_reference (expr);
3855 timevar_cond_stop (TV_OVERLOAD, subtime);
3859 /* Subroutine of convert_nontype_argument.
3861 EXPR is an argument for a template non-type parameter of integral or
3862 enumeration type. Do any necessary conversions (that are permitted for
3863 non-type arguments) to convert it to the parameter type.
3865 If conversion is successful, returns the converted expression;
3866 otherwise, returns error_mark_node. */
3869 build_integral_nontype_arg_conv (tree type, tree expr, tsubst_flags_t complain)
3874 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
3876 if (error_operand_p (expr))
3877 return error_mark_node;
3879 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
3881 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3882 p = conversion_obstack_alloc (0);
3884 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
3886 LOOKUP_IMPLICIT, complain);
3888 /* for a non-type template-parameter of integral or
3889 enumeration type, integral promotions (4.5) and integral
3890 conversions (4.7) are applied. */
3891 /* It should be sufficient to check the outermost conversion step, since
3892 there are no qualification conversions to integer type. */
3896 /* A conversion function is OK. If it isn't constexpr, we'll
3897 complain later that the argument isn't constant. */
3899 /* The lvalue-to-rvalue conversion is OK. */
3905 t = next_conversion (conv)->type;
3906 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t))
3909 if (complain & tf_error)
3910 error_at (loc, "conversion from %qT to %qT not considered for "
3911 "non-type template argument", t, type);
3912 /* and fall through. */
3920 expr = convert_like (conv, expr, complain);
3922 expr = error_mark_node;
3924 /* Free all the conversions we allocated. */
3925 obstack_free (&conversion_obstack, p);
3930 /* Do any initial processing on the arguments to a function call. */
3932 static vec<tree, va_gc> *
3933 resolve_args (vec<tree, va_gc> *args, tsubst_flags_t complain)
3938 FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
3940 if (error_operand_p (arg))
3942 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3944 if (complain & tf_error)
3945 error ("invalid use of void expression");
3948 else if (invalid_nonstatic_memfn_p (arg, complain))
3954 /* Perform overload resolution on FN, which is called with the ARGS.
3956 Return the candidate function selected by overload resolution, or
3957 NULL if the event that overload resolution failed. In the case
3958 that overload resolution fails, *CANDIDATES will be the set of
3959 candidates considered, and ANY_VIABLE_P will be set to true or
3960 false to indicate whether or not any of the candidates were
3963 The ARGS should already have gone through RESOLVE_ARGS before this
3964 function is called. */
3966 static struct z_candidate *
3967 perform_overload_resolution (tree fn,
3968 const vec<tree, va_gc> *args,
3969 struct z_candidate **candidates,
3970 bool *any_viable_p, tsubst_flags_t complain)
3972 struct z_candidate *cand;
3973 tree explicit_targs;
3976 bool subtime = timevar_cond_start (TV_OVERLOAD);
3978 explicit_targs = NULL_TREE;
3982 *any_viable_p = true;
3985 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3986 || TREE_CODE (fn) == TEMPLATE_DECL
3987 || TREE_CODE (fn) == OVERLOAD
3988 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3990 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3992 explicit_targs = TREE_OPERAND (fn, 1);
3993 fn = TREE_OPERAND (fn, 0);
3997 /* Add the various candidate functions. */
3998 add_candidates (fn, NULL_TREE, args, NULL_TREE,
3999 explicit_targs, template_only,
4000 /*conversion_path=*/NULL_TREE,
4001 /*access_path=*/NULL_TREE,
4003 candidates, complain);
4005 *candidates = splice_viable (*candidates, false, any_viable_p);
4007 cand = tourney (*candidates, complain);
4011 timevar_cond_stop (TV_OVERLOAD, subtime);
4015 /* Print an error message about being unable to build a call to FN with
4016 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4017 be located; CANDIDATES is a possibly empty list of such
4021 print_error_for_call_failure (tree fn, vec<tree, va_gc> *args,
4022 struct z_candidate *candidates)
4024 tree name = DECL_NAME (OVL_CURRENT (fn));
4025 location_t loc = location_of (name);
4027 if (!any_strictly_viable (candidates))
4028 error_at (loc, "no matching function for call to %<%D(%A)%>",
4029 name, build_tree_list_vec (args));
4031 error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous",
4032 name, build_tree_list_vec (args));
4034 print_z_candidates (loc, candidates);
4037 /* Return an expression for a call to FN (a namespace-scope function,
4038 or a static member function) with the ARGS. This may change
4042 build_new_function_call (tree fn, vec<tree, va_gc> **args, bool koenig_p,
4043 tsubst_flags_t complain)
4045 struct z_candidate *candidates, *cand;
4050 if (args != NULL && *args != NULL)
4052 *args = resolve_args (*args, complain);
4054 return error_mark_node;
4058 tm_malloc_replacement (fn);
4060 /* If this function was found without using argument dependent
4061 lookup, then we want to ignore any undeclared friend
4067 fn = remove_hidden_names (fn);
4070 if (complain & tf_error)
4071 print_error_for_call_failure (orig_fn, *args, NULL);
4072 return error_mark_node;
4076 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4077 p = conversion_obstack_alloc (0);
4079 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p,
4084 if (complain & tf_error)
4086 if (!any_viable_p && candidates && ! candidates->next
4087 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
4088 return cp_build_function_call_vec (candidates->fn, args, complain);
4089 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
4090 fn = TREE_OPERAND (fn, 0);
4091 print_error_for_call_failure (fn, *args, candidates);
4093 result = error_mark_node;
4097 int flags = LOOKUP_NORMAL;
4098 /* If fn is template_id_expr, the call has explicit template arguments
4099 (e.g. func<int>(5)), communicate this info to build_over_call
4100 through flags so that later we can use it to decide whether to warn
4101 about peculiar null pointer conversion. */
4102 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
4103 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
4104 result = build_over_call (cand, flags, complain);
4107 /* Free all the conversions we allocated. */
4108 obstack_free (&conversion_obstack, p);
4113 /* Build a call to a global operator new. FNNAME is the name of the
4114 operator (either "operator new" or "operator new[]") and ARGS are
4115 the arguments provided. This may change ARGS. *SIZE points to the
4116 total number of bytes required by the allocation, and is updated if
4117 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4118 be used. If this function determines that no cookie should be
4119 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4120 is not NULL_TREE, it is evaluated before calculating the final
4121 array size, and if it fails, the array size is replaced with
4122 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4123 is non-NULL, it will be set, upon return, to the allocation
4127 build_operator_new_call (tree fnname, vec<tree, va_gc> **args,
4128 tree *size, tree *cookie_size, tree size_check,
4129 tree *fn, tsubst_flags_t complain)
4131 tree original_size = *size;
4133 struct z_candidate *candidates;
4134 struct z_candidate *cand;
4139 /* Set to (size_t)-1 if the size check fails. */
4140 if (size_check != NULL_TREE)
4142 tree errval = TYPE_MAX_VALUE (sizetype);
4143 if (cxx_dialect >= cxx11 && flag_exceptions)
4144 errval = throw_bad_array_new_length ();
4145 *size = fold_build3 (COND_EXPR, sizetype, size_check,
4146 original_size, errval);
4148 vec_safe_insert (*args, 0, *size);
4149 *args = resolve_args (*args, complain);
4151 return error_mark_node;
4157 If this lookup fails to find the name, or if the allocated type
4158 is not a class type, the allocation function's name is looked
4159 up in the global scope.
4161 we disregard block-scope declarations of "operator new". */
4162 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
4164 /* Figure out what function is being called. */
4165 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p,
4168 /* If no suitable function could be found, issue an error message
4172 if (complain & tf_error)
4173 print_error_for_call_failure (fns, *args, candidates);
4174 return error_mark_node;
4177 /* If a cookie is required, add some extra space. Whether
4178 or not a cookie is required cannot be determined until
4179 after we know which function was called. */
4182 bool use_cookie = true;
4185 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
4186 /* Skip the size_t parameter. */
4187 arg_types = TREE_CHAIN (arg_types);
4188 /* Check the remaining parameters (if any). */
4190 && TREE_CHAIN (arg_types) == void_list_node
4191 && same_type_p (TREE_VALUE (arg_types),
4194 /* If we need a cookie, adjust the number of bytes allocated. */
4197 /* Update the total size. */
4198 *size = size_binop (PLUS_EXPR, original_size, *cookie_size);
4199 /* Set to (size_t)-1 if the size check fails. */
4200 gcc_assert (size_check != NULL_TREE);
4201 *size = fold_build3 (COND_EXPR, sizetype, size_check,
4202 *size, TYPE_MAX_VALUE (sizetype));
4203 /* Update the argument list to reflect the adjusted size. */
4204 (**args)[0] = *size;
4207 *cookie_size = NULL_TREE;
4210 /* Tell our caller which function we decided to call. */
4214 /* Build the CALL_EXPR. */
4215 return build_over_call (cand, LOOKUP_NORMAL, complain);
4218 /* Build a new call to operator(). This may change ARGS. */
4221 build_op_call_1 (tree obj, vec<tree, va_gc> **args, tsubst_flags_t complain)
4223 struct z_candidate *candidates = 0, *cand;
4224 tree fns, convs, first_mem_arg = NULL_TREE;
4225 tree type = TREE_TYPE (obj);
4227 tree result = NULL_TREE;
4230 if (error_operand_p (obj))
4231 return error_mark_node;
4233 obj = prep_operand (obj);
4235 if (TYPE_PTRMEMFUNC_P (type))
4237 if (complain & tf_error)
4238 /* It's no good looking for an overloaded operator() on a
4239 pointer-to-member-function. */
4240 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
4241 return error_mark_node;
4244 if (TYPE_BINFO (type))
4246 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
4247 if (fns == error_mark_node)
4248 return error_mark_node;
4253 if (args != NULL && *args != NULL)
4255 *args = resolve_args (*args, complain);
4257 return error_mark_node;
4260 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4261 p = conversion_obstack_alloc (0);
4265 first_mem_arg = obj;
4267 add_candidates (BASELINK_FUNCTIONS (fns),
4268 first_mem_arg, *args, NULL_TREE,
4270 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
4271 LOOKUP_NORMAL, &candidates, complain);
4274 convs = lookup_conversions (type);
4276 for (; convs; convs = TREE_CHAIN (convs))
4278 tree fns = TREE_VALUE (convs);
4279 tree totype = TREE_TYPE (convs);
4281 if (TYPE_PTRFN_P (totype)
4282 || TYPE_REFFN_P (totype)
4283 || (TREE_CODE (totype) == REFERENCE_TYPE
4284 && TYPE_PTRFN_P (TREE_TYPE (totype))))
4285 for (; fns; fns = OVL_NEXT (fns))
4287 tree fn = OVL_CURRENT (fns);
4289 if (DECL_NONCONVERTING_P (fn))
4292 if (TREE_CODE (fn) == TEMPLATE_DECL)
4293 add_template_conv_candidate
4294 (&candidates, fn, obj, NULL_TREE, *args, totype,
4295 /*access_path=*/NULL_TREE,
4296 /*conversion_path=*/NULL_TREE, complain);
4298 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
4299 *args, /*conversion_path=*/NULL_TREE,
4300 /*access_path=*/NULL_TREE, complain);
4304 /* Be strict here because if we choose a bad conversion candidate, the
4305 errors we get won't mention the call context. */
4306 candidates = splice_viable (candidates, true, &any_viable_p);
4309 if (complain & tf_error)
4311 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
4312 build_tree_list_vec (*args));
4313 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4315 result = error_mark_node;
4319 cand = tourney (candidates, complain);
4322 if (complain & tf_error)
4324 error ("call of %<(%T) (%A)%> is ambiguous",
4325 TREE_TYPE (obj), build_tree_list_vec (*args));
4326 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4328 result = error_mark_node;
4330 /* Since cand->fn will be a type, not a function, for a conversion
4331 function, we must be careful not to unconditionally look at
4333 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
4334 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
4335 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4338 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
4340 obj = convert_from_reference (obj);
4341 result = cp_build_function_call_vec (obj, args, complain);
4345 /* Free all the conversions we allocated. */
4346 obstack_free (&conversion_obstack, p);
4351 /* Wrapper for above. */
4354 build_op_call (tree obj, vec<tree, va_gc> **args, tsubst_flags_t complain)
4357 bool subtime = timevar_cond_start (TV_OVERLOAD);
4358 ret = build_op_call_1 (obj, args, complain);
4359 timevar_cond_stop (TV_OVERLOAD, subtime);
4363 /* Called by op_error to prepare format strings suitable for the error
4364 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4365 and a suffix (controlled by NTYPES). */
4368 op_error_string (const char *errmsg, int ntypes, bool match)
4372 const char *msgp = concat (match ? G_("ambiguous overload for ")
4373 : G_("no match for "), errmsg, NULL);
4376 msg = concat (msgp, G_(" (operand types are %qT, %qT, and %qT)"), NULL);
4377 else if (ntypes == 2)
4378 msg = concat (msgp, G_(" (operand types are %qT and %qT)"), NULL);
4380 msg = concat (msgp, G_(" (operand type is %qT)"), NULL);
4386 op_error (location_t loc, enum tree_code code, enum tree_code code2,
4387 tree arg1, tree arg2, tree arg3, bool match)
4391 if (code == MODIFY_EXPR)
4392 opname = assignment_operator_name_info[code2].name;
4394 opname = operator_name_info[code].name;
4399 if (flag_diagnostics_show_caret)
4400 error_at (loc, op_error_string (G_("ternary %<operator?:%>"),
4402 TREE_TYPE (arg1), TREE_TYPE (arg2), TREE_TYPE (arg3));
4404 error_at (loc, op_error_string (G_("ternary %<operator?:%> "
4405 "in %<%E ? %E : %E%>"), 3, match),
4407 TREE_TYPE (arg1), TREE_TYPE (arg2), TREE_TYPE (arg3));
4410 case POSTINCREMENT_EXPR:
4411 case POSTDECREMENT_EXPR:
4412 if (flag_diagnostics_show_caret)
4413 error_at (loc, op_error_string (G_("%<operator%s%>"), 1, match),
4414 opname, TREE_TYPE (arg1));
4416 error_at (loc, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4418 opname, arg1, opname, TREE_TYPE (arg1));
4422 if (flag_diagnostics_show_caret)
4423 error_at (loc, op_error_string (G_("%<operator[]%>"), 2, match),
4424 TREE_TYPE (arg1), TREE_TYPE (arg2));
4426 error_at (loc, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4428 arg1, arg2, TREE_TYPE (arg1), TREE_TYPE (arg2));
4433 if (flag_diagnostics_show_caret)
4434 error_at (loc, op_error_string (G_("%qs"), 1, match),
4435 opname, TREE_TYPE (arg1));
4437 error_at (loc, op_error_string (G_("%qs in %<%s %E%>"), 1, match),
4438 opname, opname, arg1, TREE_TYPE (arg1));
4443 if (flag_diagnostics_show_caret)
4444 error_at (loc, op_error_string (G_("%<operator%s%>"), 2, match),
4445 opname, TREE_TYPE (arg1), TREE_TYPE (arg2));
4447 error_at (loc, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4449 opname, arg1, opname, arg2,
4450 TREE_TYPE (arg1), TREE_TYPE (arg2));
4452 if (flag_diagnostics_show_caret)
4453 error_at (loc, op_error_string (G_("%<operator%s%>"), 1, match),
4454 opname, TREE_TYPE (arg1));
4456 error_at (loc, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4458 opname, opname, arg1, TREE_TYPE (arg1));
4463 /* Return the implicit conversion sequence that could be used to
4464 convert E1 to E2 in [expr.cond]. */
4467 conditional_conversion (tree e1, tree e2, tsubst_flags_t complain)
4469 tree t1 = non_reference (TREE_TYPE (e1));
4470 tree t2 = non_reference (TREE_TYPE (e2));
4476 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4477 implicitly converted (clause _conv_) to the type "lvalue reference to
4478 T2", subject to the constraint that in the conversion the
4479 reference must bind directly (_dcl.init.ref_) to an lvalue.
4481 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4482 implicitly converted to the type "rvalue reference to T2", subject to
4483 the constraint that the reference must bind directly. */
4484 if (lvalue_or_rvalue_with_address_p (e2))
4486 tree rtype = cp_build_reference_type (t2, !real_lvalue_p (e2));
4487 conv = implicit_conversion (rtype,
4491 LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND
4492 |LOOKUP_ONLYCONVERTING,
4494 if (conv && !conv->bad_p)
4498 /* If E2 is a prvalue or if neither of the conversions above can be done
4499 and at least one of the operands has (possibly cv-qualified) class
4501 if (!CLASS_TYPE_P (t1) && !CLASS_TYPE_P (t2))
4506 If E1 and E2 have class type, and the underlying class types are
4507 the same or one is a base class of the other: E1 can be converted
4508 to match E2 if the class of T2 is the same type as, or a base
4509 class of, the class of T1, and the cv-qualification of T2 is the
4510 same cv-qualification as, or a greater cv-qualification than, the
4511 cv-qualification of T1. If the conversion is applied, E1 is
4512 changed to an rvalue of type T2 that still refers to the original
4513 source class object (or the appropriate subobject thereof). */
4514 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
4515 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
4517 if (good_base && at_least_as_qualified_p (t2, t1))
4519 conv = build_identity_conv (t1, e1);
4520 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
4521 TYPE_MAIN_VARIANT (t2)))
4522 conv = build_conv (ck_base, t2, conv);
4524 conv = build_conv (ck_rvalue, t2, conv);
4533 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4534 converted to the type that expression E2 would have if E2 were
4535 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4536 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
4537 LOOKUP_IMPLICIT, complain);
4540 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4541 arguments to the conditional expression. */
4544 build_conditional_expr_1 (location_t loc, tree arg1, tree arg2, tree arg3,
4545 tsubst_flags_t complain)
4549 tree result = NULL_TREE;
4550 tree result_type = NULL_TREE;
4551 bool lvalue_p = true;
4552 struct z_candidate *candidates = 0;
4553 struct z_candidate *cand;
4555 tree orig_arg2, orig_arg3;
4557 /* As a G++ extension, the second argument to the conditional can be
4558 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4559 c'.) If the second operand is omitted, make sure it is
4560 calculated only once. */
4563 if (complain & tf_error)
4564 pedwarn (loc, OPT_Wpedantic,
4565 "ISO C++ forbids omitting the middle term of a ?: expression");
4567 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4568 if (real_lvalue_p (arg1))
4569 arg2 = arg1 = stabilize_reference (arg1);
4571 arg2 = arg1 = save_expr (arg1);
4574 /* If something has already gone wrong, just pass that fact up the
4576 if (error_operand_p (arg1)
4577 || error_operand_p (arg2)
4578 || error_operand_p (arg3))
4579 return error_mark_node;
4584 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1)))
4586 arg1 = force_rvalue (arg1, complain);
4587 arg2 = force_rvalue (arg2, complain);
4588 arg3 = force_rvalue (arg3, complain);
4590 /* force_rvalue can return error_mark on valid arguments. */
4591 if (error_operand_p (arg1)
4592 || error_operand_p (arg2)
4593 || error_operand_p (arg3))
4594 return error_mark_node;
4596 tree arg1_type = TREE_TYPE (arg1);
4597 arg2_type = TREE_TYPE (arg2);
4598 arg3_type = TREE_TYPE (arg3);
4600 if (TREE_CODE (arg2_type) != VECTOR_TYPE
4601 && TREE_CODE (arg3_type) != VECTOR_TYPE)
4603 /* Rely on the error messages of the scalar version. */
4604 tree scal = build_conditional_expr_1 (loc, integer_one_node,
4605 orig_arg2, orig_arg3, complain);
4606 if (scal == error_mark_node)
4607 return error_mark_node;
4608 tree stype = TREE_TYPE (scal);
4609 tree ctype = TREE_TYPE (arg1_type);
4610 if (TYPE_SIZE (stype) != TYPE_SIZE (ctype)
4611 || (!INTEGRAL_TYPE_P (stype) && !SCALAR_FLOAT_TYPE_P (stype)))
4613 if (complain & tf_error)
4614 error_at (loc, "inferred scalar type %qT is not an integer or "
4615 "floating point type of the same size as %qT", stype,
4616 COMPARISON_CLASS_P (arg1)
4617 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1, 0)))
4619 return error_mark_node;
4622 tree vtype = build_opaque_vector_type (stype,
4623 TYPE_VECTOR_SUBPARTS (arg1_type));
4624 /* We could pass complain & tf_warning to unsafe_conversion_p,
4625 but the warnings (like Wsign-conversion) have already been
4626 given by the scalar build_conditional_expr_1. We still check
4627 unsafe_conversion_p to forbid truncating long long -> float. */
4628 if (unsafe_conversion_p (loc, stype, arg2, false))
4630 if (complain & tf_error)
4631 error_at (loc, "conversion of scalar %qT to vector %qT "
4632 "involves truncation", arg2_type, vtype);
4633 return error_mark_node;
4635 if (unsafe_conversion_p (loc, stype, arg3, false))
4637 if (complain & tf_error)
4638 error_at (loc, "conversion of scalar %qT to vector %qT "
4639 "involves truncation", arg3_type, vtype);
4640 return error_mark_node;
4643 arg2 = cp_convert (stype, arg2, complain);
4644 arg2 = save_expr (arg2);
4645 arg2 = build_vector_from_val (vtype, arg2);
4647 arg3 = cp_convert (stype, arg3, complain);
4648 arg3 = save_expr (arg3);
4649 arg3 = build_vector_from_val (vtype, arg3);
4653 if ((TREE_CODE (arg2_type) == VECTOR_TYPE)
4654 != (TREE_CODE (arg3_type) == VECTOR_TYPE))
4656 enum stv_conv convert_flag =
4657 scalar_to_vector (loc, VEC_COND_EXPR, arg2, arg3,
4658 complain & tf_error);
4660 switch (convert_flag)
4663 return error_mark_node;
4666 arg2 = save_expr (arg2);
4667 arg2 = convert (TREE_TYPE (arg3_type), arg2);
4668 arg2 = build_vector_from_val (arg3_type, arg2);
4669 arg2_type = TREE_TYPE (arg2);
4674 arg3 = save_expr (arg3);
4675 arg3 = convert (TREE_TYPE (arg2_type), arg3);
4676 arg3 = build_vector_from_val (arg2_type, arg3);
4677 arg3_type = TREE_TYPE (arg3);
4685 if (!same_type_p (arg2_type, arg3_type)
4686 || TYPE_VECTOR_SUBPARTS (arg1_type)
4687 != TYPE_VECTOR_SUBPARTS (arg2_type)
4688 || TYPE_SIZE (arg1_type) != TYPE_SIZE (arg2_type))
4690 if (complain & tf_error)
4692 "incompatible vector types in conditional expression: "
4693 "%qT, %qT and %qT", TREE_TYPE (arg1),
4694 TREE_TYPE (orig_arg2), TREE_TYPE (orig_arg3));
4695 return error_mark_node;
4698 if (!COMPARISON_CLASS_P (arg1))
4699 arg1 = cp_build_binary_op (loc, NE_EXPR, arg1,
4700 build_zero_cst (arg1_type), complain);
4701 return fold_build3 (VEC_COND_EXPR, arg2_type, arg1, arg2, arg3);
4706 The first expression is implicitly converted to bool (clause
4708 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
4710 if (error_operand_p (arg1))
4711 return error_mark_node;
4715 If either the second or the third operand has type (possibly
4716 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4717 array-to-pointer (_conv.array_), and function-to-pointer
4718 (_conv.func_) standard conversions are performed on the second
4719 and third operands. */
4720 arg2_type = unlowered_expr_type (arg2);
4721 arg3_type = unlowered_expr_type (arg3);
4722 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
4724 /* Do the conversions. We don't these for `void' type arguments
4725 since it can't have any effect and since decay_conversion
4726 does not handle that case gracefully. */
4727 if (!VOID_TYPE_P (arg2_type))
4728 arg2 = decay_conversion (arg2, complain);
4729 if (!VOID_TYPE_P (arg3_type))
4730 arg3 = decay_conversion (arg3, complain);
4731 arg2_type = TREE_TYPE (arg2);
4732 arg3_type = TREE_TYPE (arg3);
4736 One of the following shall hold:
4738 --The second or the third operand (but not both) is a
4739 throw-expression (_except.throw_); the result is of the
4740 type of the other and is an rvalue.
4742 --Both the second and the third operands have type void; the
4743 result is of type void and is an rvalue.
4745 We must avoid calling force_rvalue for expressions of type
4746 "void" because it will complain that their value is being
4748 if (TREE_CODE (arg2) == THROW_EXPR
4749 && TREE_CODE (arg3) != THROW_EXPR)
4751 if (!VOID_TYPE_P (arg3_type))
4753 arg3 = force_rvalue (arg3, complain);
4754 if (arg3 == error_mark_node)
4755 return error_mark_node;
4757 arg3_type = TREE_TYPE (arg3);
4758 result_type = arg3_type;
4760 else if (TREE_CODE (arg2) != THROW_EXPR
4761 && TREE_CODE (arg3) == THROW_EXPR)
4763 if (!VOID_TYPE_P (arg2_type))
4765 arg2 = force_rvalue (arg2, complain);
4766 if (arg2 == error_mark_node)
4767 return error_mark_node;
4769 arg2_type = TREE_TYPE (arg2);
4770 result_type = arg2_type;
4772 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
4773 result_type = void_type_node;
4776 if (complain & tf_error)
4778 if (VOID_TYPE_P (arg2_type))
4779 error_at (EXPR_LOC_OR_LOC (arg3, loc),
4780 "second operand to the conditional operator "
4781 "is of type %<void%>, but the third operand is "
4782 "neither a throw-expression nor of type %<void%>");
4784 error_at (EXPR_LOC_OR_LOC (arg2, loc),
4785 "third operand to the conditional operator "
4786 "is of type %<void%>, but the second operand is "
4787 "neither a throw-expression nor of type %<void%>");
4789 return error_mark_node;
4793 goto valid_operands;
4797 Otherwise, if the second and third operand have different types,
4798 and either has (possibly cv-qualified) class type, or if both are
4799 glvalues of the same value category and the same type except for
4800 cv-qualification, an attempt is made to convert each of those operands
4801 to the type of the other. */
4802 else if (!same_type_p (arg2_type, arg3_type)
4803 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)
4804 || (same_type_ignoring_top_level_qualifiers_p (arg2_type,
4806 && lvalue_or_rvalue_with_address_p (arg2)
4807 && lvalue_or_rvalue_with_address_p (arg3)
4808 && real_lvalue_p (arg2) == real_lvalue_p (arg3))))
4812 bool converted = false;
4814 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4815 p = conversion_obstack_alloc (0);
4817 conv2 = conditional_conversion (arg2, arg3, complain);
4818 conv3 = conditional_conversion (arg3, arg2, complain);
4822 If both can be converted, or one can be converted but the
4823 conversion is ambiguous, the program is ill-formed. If
4824 neither can be converted, the operands are left unchanged and
4825 further checking is performed as described below. If exactly
4826 one conversion is possible, that conversion is applied to the
4827 chosen operand and the converted operand is used in place of
4828 the original operand for the remainder of this section. */
4829 if ((conv2 && !conv2->bad_p
4830 && conv3 && !conv3->bad_p)
4831 || (conv2 && conv2->kind == ck_ambig)
4832 || (conv3 && conv3->kind == ck_ambig))
4834 if (complain & tf_error)
4836 error_at (loc, "operands to ?: have different types %qT and %qT",
4837 arg2_type, arg3_type);
4838 if (conv2 && !conv2->bad_p && conv3 && !conv3->bad_p)
4839 inform (loc, " and each type can be converted to the other");
4840 else if (conv2 && conv2->kind == ck_ambig)
4841 convert_like (conv2, arg2, complain);
4843 convert_like (conv3, arg3, complain);
4845 result = error_mark_node;
4847 else if (conv2 && !conv2->bad_p)
4849 arg2 = convert_like (conv2, arg2, complain);
4850 arg2 = convert_from_reference (arg2);
4851 arg2_type = TREE_TYPE (arg2);
4852 /* Even if CONV2 is a valid conversion, the result of the
4853 conversion may be invalid. For example, if ARG3 has type
4854 "volatile X", and X does not have a copy constructor
4855 accepting a "volatile X&", then even if ARG2 can be
4856 converted to X, the conversion will fail. */
4857 if (error_operand_p (arg2))
4858 result = error_mark_node;
4861 else if (conv3 && !conv3->bad_p)
4863 arg3 = convert_like (conv3, arg3, complain);
4864 arg3 = convert_from_reference (arg3);
4865 arg3_type = TREE_TYPE (arg3);
4866 if (error_operand_p (arg3))
4867 result = error_mark_node;
4871 /* Free all the conversions we allocated. */
4872 obstack_free (&conversion_obstack, p);
4877 /* If, after the conversion, both operands have class type,
4878 treat the cv-qualification of both operands as if it were the
4879 union of the cv-qualification of the operands.
4881 The standard is not clear about what to do in this
4882 circumstance. For example, if the first operand has type
4883 "const X" and the second operand has a user-defined
4884 conversion to "volatile X", what is the type of the second
4885 operand after this step? Making it be "const X" (matching
4886 the first operand) seems wrong, as that discards the
4887 qualification without actually performing a copy. Leaving it
4888 as "volatile X" seems wrong as that will result in the
4889 conditional expression failing altogether, even though,
4890 according to this step, the one operand could be converted to
4891 the type of the other. */
4893 && CLASS_TYPE_P (arg2_type)
4894 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
4895 arg2_type = arg3_type =
4896 cp_build_qualified_type (arg2_type,
4897 cp_type_quals (arg2_type)
4898 | cp_type_quals (arg3_type));
4903 If the second and third operands are glvalues of the same value
4904 category and have the same type, the result is of that type and
4906 if (((real_lvalue_p (arg2) && real_lvalue_p (arg3))
4907 || (xvalue_p (arg2) && xvalue_p (arg3)))
4908 && same_type_p (arg2_type, arg3_type))
4910 result_type = arg2_type;
4911 arg2 = mark_lvalue_use (arg2);
4912 arg3 = mark_lvalue_use (arg3);
4913 goto valid_operands;
4918 Otherwise, the result is an rvalue. If the second and third
4919 operand do not have the same type, and either has (possibly
4920 cv-qualified) class type, overload resolution is used to
4921 determine the conversions (if any) to be applied to the operands
4922 (_over.match.oper_, _over.built_). */
4924 if (!same_type_p (arg2_type, arg3_type)
4925 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4931 /* Rearrange the arguments so that add_builtin_candidate only has
4932 to know about two args. In build_builtin_candidate, the
4933 arguments are unscrambled. */
4937 add_builtin_candidates (&candidates,
4940 ansi_opname (COND_EXPR),
4942 LOOKUP_NORMAL, complain);
4946 If the overload resolution fails, the program is
4948 candidates = splice_viable (candidates, false, &any_viable_p);
4951 if (complain & tf_error)
4952 error_at (loc, "operands to ?: have different types %qT and %qT",
4953 arg2_type, arg3_type);
4954 return error_mark_node;
4956 cand = tourney (candidates, complain);
4959 if (complain & tf_error)
4961 op_error (loc, COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4962 print_z_candidates (loc, candidates);
4964 return error_mark_node;
4969 Otherwise, the conversions thus determined are applied, and
4970 the converted operands are used in place of the original
4971 operands for the remainder of this section. */
4972 conv = cand->convs[0];
4973 arg1 = convert_like (conv, arg1, complain);
4974 conv = cand->convs[1];
4975 arg2 = convert_like (conv, arg2, complain);
4976 arg2_type = TREE_TYPE (arg2);
4977 conv = cand->convs[2];
4978 arg3 = convert_like (conv, arg3, complain);
4979 arg3_type = TREE_TYPE (arg3);
4984 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
4985 and function-to-pointer (_conv.func_) standard conversions are
4986 performed on the second and third operands.
4988 We need to force the lvalue-to-rvalue conversion here for class types,
4989 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
4990 that isn't wrapped with a TARGET_EXPR plays havoc with exception
4993 arg2 = force_rvalue (arg2, complain);
4994 if (!CLASS_TYPE_P (arg2_type))
4995 arg2_type = TREE_TYPE (arg2);
4997 arg3 = force_rvalue (arg3, complain);
4998 if (!CLASS_TYPE_P (arg3_type))
4999 arg3_type = TREE_TYPE (arg3);
5001 if (arg2 == error_mark_node || arg3 == error_mark_node)
5002 return error_mark_node;
5006 After those conversions, one of the following shall hold:
5008 --The second and third operands have the same type; the result is of
5010 if (same_type_p (arg2_type, arg3_type))
5011 result_type = arg2_type;
5014 --The second and third operands have arithmetic or enumeration
5015 type; the usual arithmetic conversions are performed to bring
5016 them to a common type, and the result is of that type. */
5017 else if ((ARITHMETIC_TYPE_P (arg2_type)
5018 || UNSCOPED_ENUM_P (arg2_type))
5019 && (ARITHMETIC_TYPE_P (arg3_type)
5020 || UNSCOPED_ENUM_P (arg3_type)))
5022 /* In this case, there is always a common type. */
5023 result_type = type_after_usual_arithmetic_conversions (arg2_type,
5025 if (complain & tf_warning)
5026 do_warn_double_promotion (result_type, arg2_type, arg3_type,
5027 "implicit conversion from %qT to %qT to "
5028 "match other result of conditional",
5031 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
5032 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
5034 if (TREE_CODE (orig_arg2) == CONST_DECL
5035 && TREE_CODE (orig_arg3) == CONST_DECL
5036 && DECL_CONTEXT (orig_arg2) == DECL_CONTEXT (orig_arg3))
5037 /* Two enumerators from the same enumeration can have different
5038 types when the enumeration is still being defined. */;
5039 else if (complain & tf_warning)
5040 warning_at (loc, OPT_Wenum_compare, "enumeral mismatch in "
5041 "conditional expression: %qT vs %qT",
5042 arg2_type, arg3_type);
5044 else if (extra_warnings
5045 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
5046 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
5047 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
5048 && !same_type_p (arg2_type,
5049 type_promotes_to (arg3_type)))))
5051 if (complain & tf_warning)
5052 warning_at (loc, OPT_Wextra, "enumeral and non-enumeral type in "
5053 "conditional expression");
5056 arg2 = perform_implicit_conversion (result_type, arg2, complain);
5057 arg3 = perform_implicit_conversion (result_type, arg3, complain);
5061 --The second and third operands have pointer type, or one has
5062 pointer type and the other is a null pointer constant; pointer
5063 conversions (_conv.ptr_) and qualification conversions
5064 (_conv.qual_) are performed to bring them to their composite
5065 pointer type (_expr.rel_). The result is of the composite
5068 --The second and third operands have pointer to member type, or
5069 one has pointer to member type and the other is a null pointer
5070 constant; pointer to member conversions (_conv.mem_) and
5071 qualification conversions (_conv.qual_) are performed to bring
5072 them to a common type, whose cv-qualification shall match the
5073 cv-qualification of either the second or the third operand.
5074 The result is of the common type. */
5075 else if ((null_ptr_cst_p (arg2)
5076 && TYPE_PTR_OR_PTRMEM_P (arg3_type))
5077 || (null_ptr_cst_p (arg3)
5078 && TYPE_PTR_OR_PTRMEM_P (arg2_type))
5079 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
5080 || (TYPE_PTRDATAMEM_P (arg2_type) && TYPE_PTRDATAMEM_P (arg3_type))
5081 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
5083 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
5084 arg3, CPO_CONDITIONAL_EXPR,
5086 if (result_type == error_mark_node)
5087 return error_mark_node;
5088 arg2 = perform_implicit_conversion (result_type, arg2, complain);
5089 arg3 = perform_implicit_conversion (result_type, arg3, complain);
5094 if (complain & tf_error)
5095 error_at (loc, "operands to ?: have different types %qT and %qT",
5096 arg2_type, arg3_type);
5097 return error_mark_node;
5100 if (arg2 == error_mark_node || arg3 == error_mark_node)
5101 return error_mark_node;
5104 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
5105 if (!cp_unevaluated_operand)
5106 /* Avoid folding within decltype (c++/42013) and noexcept. */
5107 result = fold_if_not_in_template (result);
5109 /* We can't use result_type below, as fold might have returned a
5114 /* Expand both sides into the same slot, hopefully the target of
5115 the ?: expression. We used to check for TARGET_EXPRs here,
5116 but now we sometimes wrap them in NOP_EXPRs so the test would
5118 if (CLASS_TYPE_P (TREE_TYPE (result)))
5119 result = get_target_expr_sfinae (result, complain);
5120 /* If this expression is an rvalue, but might be mistaken for an
5121 lvalue, we must add a NON_LVALUE_EXPR. */
5122 result = rvalue (result);
5125 result = force_paren_expr (result);
5130 /* Wrapper for above. */
5133 build_conditional_expr (location_t loc, tree arg1, tree arg2, tree arg3,
5134 tsubst_flags_t complain)
5137 bool subtime = timevar_cond_start (TV_OVERLOAD);
5138 ret = build_conditional_expr_1 (loc, arg1, arg2, arg3, complain);
5139 timevar_cond_stop (TV_OVERLOAD, subtime);
5143 /* OPERAND is an operand to an expression. Perform necessary steps
5144 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5148 prep_operand (tree operand)
5152 if (CLASS_TYPE_P (TREE_TYPE (operand))
5153 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
5154 /* Make sure the template type is instantiated now. */
5155 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
5161 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5162 OVERLOAD) to the CANDIDATES, returning an updated list of
5163 CANDIDATES. The ARGS are the arguments provided to the call;
5164 if FIRST_ARG is non-null it is the implicit object argument,
5165 otherwise the first element of ARGS is used if needed. The
5166 EXPLICIT_TARGS are explicit template arguments provided.
5167 TEMPLATE_ONLY is true if only template functions should be
5168 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5169 add_function_candidate. */
5172 add_candidates (tree fns, tree first_arg, const vec<tree, va_gc> *args,
5174 tree explicit_targs, bool template_only,
5175 tree conversion_path, tree access_path,
5177 struct z_candidate **candidates,
5178 tsubst_flags_t complain)
5181 const vec<tree, va_gc> *non_static_args;
5182 bool check_list_ctor;
5183 bool check_converting;
5184 unification_kind_t strict;
5190 /* Precalculate special handling of constructors and conversion ops. */
5191 fn = OVL_CURRENT (fns);
5192 if (DECL_CONV_FN_P (fn))
5194 check_list_ctor = false;
5195 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
5196 if (flags & LOOKUP_NO_CONVERSION)
5197 /* We're doing return_type(x). */
5198 strict = DEDUCE_CONV;
5200 /* We're doing x.operator return_type(). */
5201 strict = DEDUCE_EXACT;
5202 /* [over.match.funcs] For conversion functions, the function
5203 is considered to be a member of the class of the implicit
5204 object argument for the purpose of defining the type of
5205 the implicit object parameter. */
5206 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (first_arg));
5210 if (DECL_CONSTRUCTOR_P (fn))
5212 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
5213 /* For list-initialization we consider explicit constructors
5214 and complain if one is chosen. */
5216 = ((flags & (LOOKUP_ONLYCONVERTING|LOOKUP_LIST_INIT_CTOR))
5217 == LOOKUP_ONLYCONVERTING);
5221 check_list_ctor = false;
5222 check_converting = false;
5224 strict = DEDUCE_CALL;
5225 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
5229 non_static_args = args;
5231 /* Delay creating the implicit this parameter until it is needed. */
5232 non_static_args = NULL;
5234 for (; fns; fns = OVL_NEXT (fns))
5237 const vec<tree, va_gc> *fn_args;
5239 fn = OVL_CURRENT (fns);
5241 if (check_converting && DECL_NONCONVERTING_P (fn))
5243 if (check_list_ctor && !is_list_ctor (fn))
5246 /* Figure out which set of arguments to use. */
5247 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
5249 /* If this function is a non-static member and we didn't get an
5250 implicit object argument, move it out of args. */
5251 if (first_arg == NULL_TREE)
5255 vec<tree, va_gc> *tempvec;
5256 vec_alloc (tempvec, args->length () - 1);
5257 for (ix = 1; args->iterate (ix, &arg); ++ix)
5258 tempvec->quick_push (arg);
5259 non_static_args = tempvec;
5260 first_arg = (*args)[0];
5263 fn_first_arg = first_arg;
5264 fn_args = non_static_args;
5268 /* Otherwise, just use the list of arguments provided. */
5269 fn_first_arg = NULL_TREE;
5273 if (TREE_CODE (fn) == TEMPLATE_DECL)
5274 add_template_candidate (candidates,
5286 else if (!template_only)
5287 add_function_candidate (candidates,
5300 build_new_op_1 (location_t loc, enum tree_code code, int flags, tree arg1,
5301 tree arg2, tree arg3, tree *overload, tsubst_flags_t complain)
5303 struct z_candidate *candidates = 0, *cand;
5304 vec<tree, va_gc> *arglist;
5307 tree result = NULL_TREE;
5308 bool result_valid_p = false;
5309 enum tree_code code2 = NOP_EXPR;
5310 enum tree_code code_orig_arg1 = ERROR_MARK;
5311 enum tree_code code_orig_arg2 = ERROR_MARK;
5317 if (error_operand_p (arg1)
5318 || error_operand_p (arg2)
5319 || error_operand_p (arg3))
5320 return error_mark_node;
5322 if (code == MODIFY_EXPR)
5324 code2 = TREE_CODE (arg3);
5326 fnname = ansi_assopname (code2);
5329 fnname = ansi_opname (code);
5331 arg1 = prep_operand (arg1);
5333 bool memonly = false;
5338 case VEC_DELETE_EXPR:
5340 /* Use build_op_new_call and build_op_delete_call instead. */
5344 /* Use build_op_call instead. */
5347 case TRUTH_ORIF_EXPR:
5348 case TRUTH_ANDIF_EXPR:
5349 case TRUTH_AND_EXPR:
5351 /* These are saved for the sake of warn_logical_operator. */
5352 code_orig_arg1 = TREE_CODE (arg1);
5353 code_orig_arg2 = TREE_CODE (arg2);
5361 /* These are saved for the sake of maybe_warn_bool_compare. */
5362 code_orig_arg1 = TREE_CODE (TREE_TYPE (arg1));
5363 code_orig_arg2 = TREE_CODE (TREE_TYPE (arg2));
5366 /* =, ->, [], () must be non-static member functions. */
5368 if (code2 != NOP_EXPR)
5379 arg2 = prep_operand (arg2);
5380 arg3 = prep_operand (arg3);
5382 if (code == COND_EXPR)
5383 /* Use build_conditional_expr instead. */
5385 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1))
5386 && (! arg2 || ! OVERLOAD_TYPE_P (TREE_TYPE (arg2))))
5389 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
5390 arg2 = integer_zero_node;
5392 vec_alloc (arglist, 3);
5393 arglist->quick_push (arg1);
5394 if (arg2 != NULL_TREE)
5395 arglist->quick_push (arg2);
5396 if (arg3 != NULL_TREE)
5397 arglist->quick_push (arg3);
5399 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5400 p = conversion_obstack_alloc (0);
5402 /* Add namespace-scope operators to the list of functions to
5405 add_candidates (lookup_function_nonclass (fnname, arglist,
5407 NULL_TREE, arglist, NULL_TREE,
5408 NULL_TREE, false, NULL_TREE, NULL_TREE,
5409 flags, &candidates, complain);
5413 args[2] = NULL_TREE;
5415 /* Add class-member operators to the candidate set. */
5416 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
5420 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
5421 if (fns == error_mark_node)
5423 result = error_mark_node;
5424 goto user_defined_result_ready;
5427 add_candidates (BASELINK_FUNCTIONS (fns),
5428 NULL_TREE, arglist, NULL_TREE,
5430 BASELINK_BINFO (fns),
5431 BASELINK_ACCESS_BINFO (fns),
5432 flags, &candidates, complain);
5434 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5435 only non-member functions that have type T1 or reference to
5436 cv-qualified-opt T1 for the first argument, if the first argument
5437 has an enumeration type, or T2 or reference to cv-qualified-opt
5438 T2 for the second argument, if the the second argument has an
5439 enumeration type. Filter out those that don't match. */
5440 else if (! arg2 || ! CLASS_TYPE_P (TREE_TYPE (arg2)))
5442 struct z_candidate **candp, **next;
5444 for (candp = &candidates; *candp; candp = next)
5446 tree parmlist, parmtype;
5447 int i, nargs = (arg2 ? 2 : 1);
5452 parmlist = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
5454 for (i = 0; i < nargs; ++i)
5456 parmtype = TREE_VALUE (parmlist);
5458 if (TREE_CODE (parmtype) == REFERENCE_TYPE)
5459 parmtype = TREE_TYPE (parmtype);
5460 if (TREE_CODE (TREE_TYPE (args[i])) == ENUMERAL_TYPE
5461 && (same_type_ignoring_top_level_qualifiers_p
5462 (TREE_TYPE (args[i]), parmtype)))
5465 parmlist = TREE_CHAIN (parmlist);
5468 /* No argument has an appropriate type, so remove this
5469 candidate function from the list. */
5472 *candp = cand->next;
5478 add_builtin_candidates (&candidates, code, code2, fnname, args,
5485 /* For these, the built-in candidates set is empty
5486 [over.match.oper]/3. We don't want non-strict matches
5487 because exact matches are always possible with built-in
5488 operators. The built-in candidate set for COMPONENT_REF
5489 would be empty too, but since there are no such built-in
5490 operators, we accept non-strict matches for them. */
5499 candidates = splice_viable (candidates, strict_p, &any_viable_p);
5504 case POSTINCREMENT_EXPR:
5505 case POSTDECREMENT_EXPR:
5506 /* Don't try anything fancy if we're not allowed to produce
5508 if (!(complain & tf_error))
5509 return error_mark_node;
5511 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5512 distinguish between prefix and postfix ++ and
5513 operator++() was used for both, so we allow this with
5517 const char *msg = (flag_permissive)
5518 ? G_("no %<%D(int)%> declared for postfix %qs,"
5519 " trying prefix operator instead")
5520 : G_("no %<%D(int)%> declared for postfix %qs");
5521 permerror (loc, msg, fnname, operator_name_info[code].name);
5524 if (!flag_permissive)
5525 return error_mark_node;
5527 if (code == POSTINCREMENT_EXPR)
5528 code = PREINCREMENT_EXPR;
5530 code = PREDECREMENT_EXPR;
5531 result = build_new_op_1 (loc, code, flags, arg1, NULL_TREE,
5532 NULL_TREE, overload, complain);
5535 /* The caller will deal with these. */
5540 result_valid_p = true;
5544 if (complain & tf_error)
5546 /* If one of the arguments of the operator represents
5547 an invalid use of member function pointer, try to report
5548 a meaningful error ... */
5549 if (invalid_nonstatic_memfn_p (arg1, tf_error)
5550 || invalid_nonstatic_memfn_p (arg2, tf_error)
5551 || invalid_nonstatic_memfn_p (arg3, tf_error))
5552 /* We displayed the error message. */;
5555 /* ... Otherwise, report the more generic
5556 "no matching operator found" error */
5557 op_error (loc, code, code2, arg1, arg2, arg3, FALSE);
5558 print_z_candidates (loc, candidates);
5561 result = error_mark_node;
5567 cand = tourney (candidates, complain);
5570 if (complain & tf_error)
5572 op_error (loc, code, code2, arg1, arg2, arg3, TRUE);
5573 print_z_candidates (loc, candidates);
5575 result = error_mark_node;
5577 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
5580 *overload = cand->fn;
5582 if (resolve_args (arglist, complain) == NULL)
5583 result = error_mark_node;
5585 result = build_over_call (cand, LOOKUP_NORMAL, complain);
5589 /* Give any warnings we noticed during overload resolution. */
5590 if (cand->warnings && (complain & tf_warning))
5592 struct candidate_warning *w;
5593 for (w = cand->warnings; w; w = w->next)
5594 joust (cand, w->loser, 1, complain);
5597 /* Check for comparison of different enum types. */
5606 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
5607 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
5608 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
5609 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
5610 && (complain & tf_warning))
5612 warning (OPT_Wenum_compare,
5613 "comparison between %q#T and %q#T",
5614 TREE_TYPE (arg1), TREE_TYPE (arg2));
5621 /* We need to strip any leading REF_BIND so that bitfields
5622 don't cause errors. This should not remove any important
5623 conversions, because builtins don't apply to class
5624 objects directly. */
5625 conv = cand->convs[0];
5626 if (conv->kind == ck_ref_bind)
5627 conv = next_conversion (conv);
5628 arg1 = convert_like (conv, arg1, complain);
5632 conv = cand->convs[1];
5633 if (conv->kind == ck_ref_bind)
5634 conv = next_conversion (conv);
5636 arg2 = decay_conversion (arg2, complain);
5638 /* We need to call warn_logical_operator before
5639 converting arg2 to a boolean_type, but after
5640 decaying an enumerator to its value. */
5641 if (complain & tf_warning)
5642 warn_logical_operator (loc, code, boolean_type_node,
5643 code_orig_arg1, arg1,
5644 code_orig_arg2, arg2);
5646 arg2 = convert_like (conv, arg2, complain);
5650 conv = cand->convs[2];
5651 if (conv->kind == ck_ref_bind)
5652 conv = next_conversion (conv);
5653 arg3 = convert_like (conv, arg3, complain);
5659 user_defined_result_ready:
5661 /* Free all the conversions we allocated. */
5662 obstack_free (&conversion_obstack, p);
5664 if (result || result_valid_p)
5671 return cp_build_modify_expr (arg1, code2, arg2, complain);
5674 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
5676 case TRUTH_ANDIF_EXPR:
5677 case TRUTH_ORIF_EXPR:
5678 case TRUTH_AND_EXPR:
5680 warn_logical_operator (loc, code, boolean_type_node,
5681 code_orig_arg1, arg1, code_orig_arg2, arg2);
5689 if ((code_orig_arg1 == BOOLEAN_TYPE)
5690 ^ (code_orig_arg2 == BOOLEAN_TYPE))
5691 maybe_warn_bool_compare (loc, code, arg1, arg2);
5696 case TRUNC_DIV_EXPR:
5701 case TRUNC_MOD_EXPR:
5705 return cp_build_binary_op (loc, code, arg1, arg2, complain);
5707 case UNARY_PLUS_EXPR:
5710 case TRUTH_NOT_EXPR:
5711 case PREINCREMENT_EXPR:
5712 case POSTINCREMENT_EXPR:
5713 case PREDECREMENT_EXPR:
5714 case POSTDECREMENT_EXPR:
5718 return cp_build_unary_op (code, arg1, candidates != 0, complain);
5721 return cp_build_array_ref (input_location, arg1, arg2, complain);
5724 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_ARROW_STAR,
5728 /* The caller will deal with these. */
5740 /* Wrapper for above. */
5743 build_new_op (location_t loc, enum tree_code code, int flags,
5744 tree arg1, tree arg2, tree arg3,
5745 tree *overload, tsubst_flags_t complain)
5748 bool subtime = timevar_cond_start (TV_OVERLOAD);
5749 ret = build_new_op_1 (loc, code, flags, arg1, arg2, arg3,
5750 overload, complain);
5751 timevar_cond_stop (TV_OVERLOAD, subtime);
5755 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5756 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5759 non_placement_deallocation_fn_p (tree t)
5761 /* A template instance is never a usual deallocation function,
5762 regardless of its signature. */
5763 if (TREE_CODE (t) == TEMPLATE_DECL
5764 || primary_template_instantiation_p (t))
5767 /* If a class T has a member deallocation function named operator delete
5768 with exactly one parameter, then that function is a usual
5769 (non-placement) deallocation function. If class T does not declare
5770 such an operator delete but does declare a member deallocation
5771 function named operator delete with exactly two parameters, the second
5772 of which has type std::size_t (18.2), then this function is a usual
5773 deallocation function. */
5774 bool global = DECL_NAMESPACE_SCOPE_P (t);
5775 t = FUNCTION_ARG_CHAIN (t);
5776 if (t == void_list_node
5777 || (t && same_type_p (TREE_VALUE (t), size_type_node)
5778 && (!global || flag_sized_deallocation)
5779 && TREE_CHAIN (t) == void_list_node))
5784 /* Build a call to operator delete. This has to be handled very specially,
5785 because the restrictions on what signatures match are different from all
5786 other call instances. For a normal delete, only a delete taking (void *)
5787 or (void *, size_t) is accepted. For a placement delete, only an exact
5788 match with the placement new is accepted.
5790 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5791 ADDR is the pointer to be deleted.
5792 SIZE is the size of the memory block to be deleted.
5793 GLOBAL_P is true if the delete-expression should not consider
5794 class-specific delete operators.
5795 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5797 If this call to "operator delete" is being generated as part to
5798 deallocate memory allocated via a new-expression (as per [expr.new]
5799 which requires that if the initialization throws an exception then
5800 we call a deallocation function), then ALLOC_FN is the allocation
5804 build_op_delete_call (enum tree_code code, tree addr, tree size,
5805 bool global_p, tree placement,
5806 tree alloc_fn, tsubst_flags_t complain)
5808 tree fn = NULL_TREE;
5809 tree fns, fnname, type, t;
5811 if (addr == error_mark_node)
5812 return error_mark_node;
5814 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
5816 fnname = ansi_opname (code);
5818 if (CLASS_TYPE_P (type)
5819 && COMPLETE_TYPE_P (complete_type (type))
5823 If the result of the lookup is ambiguous or inaccessible, or if
5824 the lookup selects a placement deallocation function, the
5825 program is ill-formed.
5827 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5829 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
5830 if (fns == error_mark_node)
5831 return error_mark_node;
5836 if (fns == NULL_TREE)
5837 fns = lookup_name_nonclass (fnname);
5839 /* Strip const and volatile from addr. */
5840 addr = cp_convert (ptr_type_node, addr, complain);
5844 /* "A declaration of a placement deallocation function matches the
5845 declaration of a placement allocation function if it has the same
5846 number of parameters and, after parameter transformations (8.3.5),
5847 all parameter types except the first are identical."
5849 So we build up the function type we want and ask instantiate_type
5850 to get it for us. */
5851 t = FUNCTION_ARG_CHAIN (alloc_fn);
5852 t = tree_cons (NULL_TREE, ptr_type_node, t);
5853 t = build_function_type (void_type_node, t);
5855 fn = instantiate_type (t, fns, tf_none);
5856 if (fn == error_mark_node)
5859 if (BASELINK_P (fn))
5860 fn = BASELINK_FUNCTIONS (fn);
5862 /* "If the lookup finds the two-parameter form of a usual deallocation
5863 function (3.7.4.2) and that function, considered as a placement
5864 deallocation function, would have been selected as a match for the
5865 allocation function, the program is ill-formed." */
5866 if (non_placement_deallocation_fn_p (fn))
5868 /* But if the class has an operator delete (void *), then that is
5869 the usual deallocation function, so we shouldn't complain
5870 about using the operator delete (void *, size_t). */
5871 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5872 t; t = OVL_NEXT (t))
5874 tree elt = OVL_CURRENT (t);
5875 if (non_placement_deallocation_fn_p (elt)
5876 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
5879 if (complain & tf_error)
5881 permerror (0, "non-placement deallocation function %q+D", fn);
5882 permerror (input_location, "selected for placement delete");
5885 return error_mark_node;
5890 /* "Any non-placement deallocation function matches a non-placement
5891 allocation function. If the lookup finds a single matching
5892 deallocation function, that function will be called; otherwise, no
5893 deallocation function will be called." */
5894 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5895 t; t = OVL_NEXT (t))
5897 tree elt = OVL_CURRENT (t);
5898 if (non_placement_deallocation_fn_p (elt))
5901 /* "If a class T has a member deallocation function named
5902 operator delete with exactly one parameter, then that
5903 function is a usual (non-placement) deallocation
5904 function. If class T does not declare such an operator
5905 delete but does declare a member deallocation function named
5906 operator delete with exactly two parameters, the second of
5907 which has type std::size_t (18.2), then this function is a
5908 usual deallocation function."
5910 So in a class (void*) beats (void*, size_t). */
5911 if (DECL_CLASS_SCOPE_P (fn))
5913 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
5916 /* At global scope (in C++14 and above) the rules are different:
5918 If deallocation function lookup finds both a usual
5919 deallocation function with only a pointer parameter and a
5920 usual deallocation function with both a pointer parameter
5921 and a size parameter, the function to be called is selected
5924 * If the type is complete and if, for the second alternative
5925 (delete array) only, the operand is a pointer to a class
5926 type with a non-trivial destructor or a (possibly
5927 multi-dimensional) array thereof, the function with two
5928 parameters is selected.
5930 * Otherwise, it is unspecified which of the two deallocation
5931 functions is selected. */
5934 bool want_size = COMPLETE_TYPE_P (type);
5935 if (code == VEC_DELETE_EXPR
5936 && !TYPE_VEC_NEW_USES_COOKIE (type))
5937 /* We need a cookie to determine the array size. */
5939 bool have_size = (FUNCTION_ARG_CHAIN (fn) != void_list_node);
5940 if (want_size == have_size)
5946 /* If we have a matching function, call it. */
5949 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5951 /* If the FN is a member function, make sure that it is
5953 if (BASELINK_P (fns))
5954 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn,
5957 /* Core issue 901: It's ok to new a type with deleted delete. */
5958 if (DECL_DELETED_FN (fn) && alloc_fn)
5963 /* The placement args might not be suitable for overload
5964 resolution at this point, so build the call directly. */
5965 int nargs = call_expr_nargs (placement);
5966 tree *argarray = XALLOCAVEC (tree, nargs);
5969 for (i = 1; i < nargs; i++)
5970 argarray[i] = CALL_EXPR_ARG (placement, i);
5972 return build_cxx_call (fn, nargs, argarray, complain);
5977 vec<tree, va_gc> *args = make_tree_vector ();
5978 args->quick_push (addr);
5979 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
5980 args->quick_push (size);
5981 ret = cp_build_function_call_vec (fn, &args, complain);
5982 release_tree_vector (args);
5989 If no unambiguous matching deallocation function can be found,
5990 propagating the exception does not cause the object's memory to
5994 if ((complain & tf_warning)
5996 warning (0, "no corresponding deallocation function for %qD",
6001 if (complain & tf_error)
6002 error ("no suitable %<operator %s%> for %qT",
6003 operator_name_info[(int)code].name, type);
6004 return error_mark_node;
6007 /* If the current scope isn't allowed to access DECL along
6008 BASETYPE_PATH, give an error. The most derived class in
6009 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6010 the declaration to use in the error diagnostic. */
6013 enforce_access (tree basetype_path, tree decl, tree diag_decl,
6014 tsubst_flags_t complain)
6016 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
6018 if (!accessible_p (basetype_path, decl, true))
6020 if (complain & tf_error)
6022 if (TREE_PRIVATE (decl))
6023 error ("%q+#D is private", diag_decl);
6024 else if (TREE_PROTECTED (decl))
6025 error ("%q+#D is protected", diag_decl);
6027 error ("%q+#D is inaccessible", diag_decl);
6028 error ("within this context");
6036 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6037 bitwise or of LOOKUP_* values. If any errors are warnings are
6038 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6039 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6043 build_temp (tree expr, tree type, int flags,
6044 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
6047 vec<tree, va_gc> *args;
6049 savew = warningcount + werrorcount, savee = errorcount;
6050 args = make_tree_vector_single (expr);
6051 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6052 &args, type, flags, complain);
6053 release_tree_vector (args);
6054 if (warningcount + werrorcount > savew)
6055 *diagnostic_kind = DK_WARNING;
6056 else if (errorcount > savee)
6057 *diagnostic_kind = DK_ERROR;
6059 *diagnostic_kind = DK_UNSPECIFIED;
6063 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6064 EXPR is implicitly converted to type TOTYPE.
6065 FN and ARGNUM are used for diagnostics. */
6068 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
6070 /* Issue warnings about peculiar, but valid, uses of NULL. */
6071 if (expr == null_node && TREE_CODE (totype) != BOOLEAN_TYPE
6072 && ARITHMETIC_TYPE_P (totype))
6074 source_location loc =
6075 expansion_point_location_if_in_system_header (input_location);
6078 warning_at (loc, OPT_Wconversion_null,
6079 "passing NULL to non-pointer argument %P of %qD",
6082 warning_at (loc, OPT_Wconversion_null,
6083 "converting to non-pointer type %qT from NULL", totype);
6086 /* Issue warnings if "false" is converted to a NULL pointer */
6087 else if (TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE
6088 && TYPE_PTR_P (totype))
6091 warning_at (input_location, OPT_Wconversion_null,
6092 "converting %<false%> to pointer type for argument %P "
6093 "of %qD", argnum, fn);
6095 warning_at (input_location, OPT_Wconversion_null,
6096 "converting %<false%> to pointer type %qT", totype);
6100 /* We gave a diagnostic during a conversion. If this was in the second
6101 standard conversion sequence of a user-defined conversion sequence, say
6102 which user-defined conversion. */
6105 maybe_print_user_conv_context (conversion *convs)
6107 if (convs->user_conv_p)
6108 for (conversion *t = convs; t; t = next_conversion (t))
6109 if (t->kind == ck_user)
6111 print_z_candidate (0, " after user-defined conversion:",
6117 /* Perform the conversions in CONVS on the expression EXPR. FN and
6118 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6119 indicates the `this' argument of a method. INNER is nonzero when
6120 being called to continue a conversion chain. It is negative when a
6121 reference binding will be applied, positive otherwise. If
6122 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6123 conversions will be emitted if appropriate. If C_CAST_P is true,
6124 this conversion is coming from a C-style cast; in that case,
6125 conversions to inaccessible bases are permitted. */
6128 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
6129 int inner, bool issue_conversion_warnings,
6130 bool c_cast_p, tsubst_flags_t complain)
6132 tree totype = convs->type;
6133 diagnostic_t diag_kind;
6135 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
6137 if (convs->bad_p && !(complain & tf_error))
6138 return error_mark_node;
6141 && convs->kind != ck_user
6142 && convs->kind != ck_list
6143 && convs->kind != ck_ambig
6144 && (convs->kind != ck_ref_bind
6145 || (convs->user_conv_p && next_conversion (convs)->bad_p))
6146 && (convs->kind != ck_rvalue
6147 || SCALAR_TYPE_P (totype))
6148 && convs->kind != ck_base)
6150 bool complained = false;
6151 conversion *t = convs;
6153 /* Give a helpful error if this is bad because of excess braces. */
6154 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
6155 && SCALAR_TYPE_P (totype)
6156 && CONSTRUCTOR_NELTS (expr) > 0
6157 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
6159 complained = permerror (loc, "too many braces around initializer "
6161 while (BRACE_ENCLOSED_INITIALIZER_P (expr)
6162 && CONSTRUCTOR_NELTS (expr) == 1)
6163 expr = CONSTRUCTOR_ELT (expr, 0)->value;
6166 /* Give a helpful error if this is bad because a conversion to bool
6167 from std::nullptr_t requires direct-initialization. */
6168 if (NULLPTR_TYPE_P (TREE_TYPE (expr))
6169 && TREE_CODE (totype) == BOOLEAN_TYPE)
6170 complained = permerror (loc, "converting to %qT from %qT requires "
6171 "direct-initialization",
6172 totype, TREE_TYPE (expr));
6174 for (; t ; t = next_conversion (t))
6176 if (t->kind == ck_user && t->cand->reason)
6178 complained = permerror (loc, "invalid user-defined conversion "
6179 "from %qT to %qT", TREE_TYPE (expr),
6182 print_z_candidate (loc, "candidate is:", t->cand);
6183 expr = convert_like_real (t, expr, fn, argnum, 1,
6184 /*issue_conversion_warnings=*/false,
6187 if (convs->kind == ck_ref_bind)
6188 expr = convert_to_reference (totype, expr, CONV_IMPLICIT,
6189 LOOKUP_NORMAL, NULL_TREE,
6192 expr = cp_convert (totype, expr, complain);
6193 if (complained && fn)
6194 inform (DECL_SOURCE_LOCATION (fn),
6195 " initializing argument %P of %qD", argnum, fn);
6198 else if (t->kind == ck_user || !t->bad_p)
6200 expr = convert_like_real (t, expr, fn, argnum, 1,
6201 /*issue_conversion_warnings=*/false,
6206 else if (t->kind == ck_ambig)
6207 return convert_like_real (t, expr, fn, argnum, 1,
6208 /*issue_conversion_warnings=*/false,
6211 else if (t->kind == ck_identity)
6215 complained = permerror (loc, "invalid conversion from %qT to %qT",
6216 TREE_TYPE (expr), totype);
6217 if (complained && fn)
6218 inform (DECL_SOURCE_LOCATION (fn),
6219 " initializing argument %P of %qD", argnum, fn);
6221 return cp_convert (totype, expr, complain);
6224 if (issue_conversion_warnings && (complain & tf_warning))
6225 conversion_null_warnings (totype, expr, fn, argnum);
6227 switch (convs->kind)
6231 struct z_candidate *cand = convs->cand;
6232 tree convfn = cand->fn;
6235 /* When converting from an init list we consider explicit
6236 constructors, but actually trying to call one is an error. */
6237 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
6238 /* Unless this is for direct-list-initialization. */
6239 && !DIRECT_LIST_INIT_P (expr))
6241 if (!(complain & tf_error))
6242 return error_mark_node;
6243 error ("converting to %qT from initializer list would use "
6244 "explicit constructor %qD", totype, convfn);
6247 /* If we're initializing from {}, it's value-initialization. */
6248 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
6249 && CONSTRUCTOR_NELTS (expr) == 0
6250 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
6252 bool direct = CONSTRUCTOR_IS_DIRECT_INIT (expr);
6253 expr = build_value_init (totype, complain);
6254 expr = get_target_expr_sfinae (expr, complain);
6255 if (expr != error_mark_node)
6257 TARGET_EXPR_LIST_INIT_P (expr) = true;
6258 TARGET_EXPR_DIRECT_INIT_P (expr) = direct;
6263 expr = mark_rvalue_use (expr);
6265 /* Set user_conv_p on the argument conversions, so rvalue/base
6266 handling knows not to allow any more UDCs. */
6267 for (i = 0; i < cand->num_convs; ++i)
6268 cand->convs[i]->user_conv_p = true;
6270 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
6272 /* If this is a constructor or a function returning an aggr type,
6273 we need to build up a TARGET_EXPR. */
6274 if (DECL_CONSTRUCTOR_P (convfn))
6276 expr = build_cplus_new (totype, expr, complain);
6278 /* Remember that this was list-initialization. */
6279 if (convs->check_narrowing && expr != error_mark_node)
6280 TARGET_EXPR_LIST_INIT_P (expr) = true;
6286 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
6288 int nelts = CONSTRUCTOR_NELTS (expr);
6290 expr = build_value_init (totype, complain);
6291 else if (nelts == 1)
6292 expr = CONSTRUCTOR_ELT (expr, 0)->value;
6296 expr = mark_rvalue_use (expr);
6298 if (type_unknown_p (expr))
6299 expr = instantiate_type (totype, expr, complain);
6300 /* Convert a constant to its underlying value, unless we are
6301 about to bind it to a reference, in which case we need to
6302 leave it as an lvalue. */
6305 expr = scalar_constant_value (expr);
6306 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
6307 /* If __null has been converted to an integer type, we do not
6308 want to warn about uses of EXPR as an integer, rather than
6310 expr = build_int_cst (totype, 0);
6314 /* We leave bad_p off ck_ambig because overload resolution considers
6315 it valid, it just fails when we try to perform it. So we need to
6316 check complain here, too. */
6317 if (complain & tf_error)
6319 /* Call build_user_type_conversion again for the error. */
6320 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL,
6323 inform (input_location, " initializing argument %P of %q+D",
6326 return error_mark_node;
6330 /* Conversion to std::initializer_list<T>. */
6331 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
6332 tree new_ctor = build_constructor (init_list_type_node, NULL);
6333 unsigned len = CONSTRUCTOR_NELTS (expr);
6334 tree array, val, field;
6335 vec<constructor_elt, va_gc> *vec = NULL;
6338 /* Convert all the elements. */
6339 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
6341 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
6342 1, false, false, complain);
6343 if (sub == error_mark_node)
6345 if (!BRACE_ENCLOSED_INITIALIZER_P (val)
6346 && !check_narrowing (TREE_TYPE (sub), val, complain))
6347 return error_mark_node;
6348 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
6349 if (!TREE_CONSTANT (sub))
6350 TREE_CONSTANT (new_ctor) = false;
6352 /* Build up the array. */
6353 elttype = cp_build_qualified_type
6354 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
6355 array = build_array_of_n_type (elttype, len);
6356 array = finish_compound_literal (array, new_ctor, complain);
6357 /* Take the address explicitly rather than via decay_conversion
6358 to avoid the error about taking the address of a temporary. */
6359 array = cp_build_addr_expr (array, complain);
6360 array = cp_convert (build_pointer_type (elttype), array, complain);
6361 if (array == error_mark_node)
6362 return error_mark_node;
6364 /* Build up the initializer_list object. */
6365 totype = complete_type (totype);
6366 field = next_initializable_field (TYPE_FIELDS (totype));
6367 CONSTRUCTOR_APPEND_ELT (vec, field, array);
6368 field = next_initializable_field (DECL_CHAIN (field));
6369 CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len));
6370 new_ctor = build_constructor (totype, vec);
6371 return get_target_expr_sfinae (new_ctor, complain);
6375 if (TREE_CODE (totype) == COMPLEX_TYPE)
6377 tree real = CONSTRUCTOR_ELT (expr, 0)->value;
6378 tree imag = CONSTRUCTOR_ELT (expr, 1)->value;
6379 real = perform_implicit_conversion (TREE_TYPE (totype),
6381 imag = perform_implicit_conversion (TREE_TYPE (totype),
6383 expr = build2 (COMPLEX_EXPR, totype, real, imag);
6384 return fold_if_not_in_template (expr);
6386 expr = reshape_init (totype, expr, complain);
6387 expr = get_target_expr_sfinae (digest_init (totype, expr, complain),
6389 if (expr != error_mark_node)
6390 TARGET_EXPR_LIST_INIT_P (expr) = true;
6397 expr = convert_like_real (next_conversion (convs), expr, fn, argnum,
6398 convs->kind == ck_ref_bind ? -1 : 1,
6399 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
6402 if (expr == error_mark_node)
6403 return error_mark_node;
6405 switch (convs->kind)
6408 expr = decay_conversion (expr, complain);
6409 if (expr == error_mark_node)
6410 return error_mark_node;
6412 if (! MAYBE_CLASS_TYPE_P (totype))
6414 /* Else fall through. */
6416 if (convs->kind == ck_base && !convs->need_temporary_p)
6418 /* We are going to bind a reference directly to a base-class
6419 subobject of EXPR. */
6420 /* Build an expression for `*((base*) &expr)'. */
6421 expr = convert_to_base (expr, totype,
6422 !c_cast_p, /*nonnull=*/true, complain);
6426 /* Copy-initialization where the cv-unqualified version of the source
6427 type is the same class as, or a derived class of, the class of the
6428 destination [is treated as direct-initialization]. [dcl.init] */
6429 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
6430 if (convs->user_conv_p)
6431 /* This conversion is being done in the context of a user-defined
6432 conversion (i.e. the second step of copy-initialization), so
6433 don't allow any more. */
6434 flags |= LOOKUP_NO_CONVERSION;
6435 if (convs->rvaluedness_matches_p)
6436 flags |= LOOKUP_PREFER_RVALUE;
6437 if (TREE_CODE (expr) == TARGET_EXPR
6438 && TARGET_EXPR_LIST_INIT_P (expr))
6439 /* Copy-list-initialization doesn't actually involve a copy. */
6441 expr = build_temp (expr, totype, flags, &diag_kind, complain);
6442 if (diag_kind && complain)
6444 maybe_print_user_conv_context (convs);
6446 inform (DECL_SOURCE_LOCATION (fn),
6447 " initializing argument %P of %qD", argnum, fn);
6450 return build_cplus_new (totype, expr, complain);
6454 tree ref_type = totype;
6456 if (convs->bad_p && !next_conversion (convs)->bad_p)
6458 tree extype = TREE_TYPE (expr);
6459 if (TYPE_REF_IS_RVALUE (ref_type)
6460 && real_lvalue_p (expr))
6461 error_at (loc, "cannot bind %qT lvalue to %qT",
6463 else if (!TYPE_REF_IS_RVALUE (ref_type) && !real_lvalue_p (expr)
6464 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
6465 error_at (loc, "invalid initialization of non-const reference of "
6466 "type %qT from an rvalue of type %qT", totype, extype);
6467 else if (!reference_compatible_p (TREE_TYPE (totype), extype))
6468 error_at (loc, "binding %qT to reference of type %qT "
6469 "discards qualifiers", extype, totype);
6472 maybe_print_user_conv_context (convs);
6474 inform (input_location,
6475 " initializing argument %P of %q+D", argnum, fn);
6476 return error_mark_node;
6479 /* If necessary, create a temporary.
6481 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
6482 that need temporaries, even when their types are reference
6483 compatible with the type of reference being bound, so the
6484 upcoming call to cp_build_addr_expr doesn't fail. */
6485 if (convs->need_temporary_p
6486 || TREE_CODE (expr) == CONSTRUCTOR
6487 || TREE_CODE (expr) == VA_ARG_EXPR)
6489 /* Otherwise, a temporary of type "cv1 T1" is created and
6490 initialized from the initializer expression using the rules
6491 for a non-reference copy-initialization (8.5). */
6493 tree type = TREE_TYPE (ref_type);
6494 cp_lvalue_kind lvalue = real_lvalue_p (expr);
6496 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6497 (type, next_conversion (convs)->type));
6498 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
6499 && !TYPE_REF_IS_RVALUE (ref_type))
6501 /* If the reference is volatile or non-const, we
6502 cannot create a temporary. */
6503 if (lvalue & clk_bitfield)
6504 error_at (loc, "cannot bind bitfield %qE to %qT",
6506 else if (lvalue & clk_packed)
6507 error_at (loc, "cannot bind packed field %qE to %qT",
6510 error_at (loc, "cannot bind rvalue %qE to %qT",
6512 return error_mark_node;
6514 /* If the source is a packed field, and we must use a copy
6515 constructor, then building the target expr will require
6516 binding the field to the reference parameter to the
6517 copy constructor, and we'll end up with an infinite
6518 loop. If we can use a bitwise copy, then we'll be
6520 if ((lvalue & clk_packed)
6521 && CLASS_TYPE_P (type)
6522 && type_has_nontrivial_copy_init (type))
6524 error_at (loc, "cannot bind packed field %qE to %qT",
6526 return error_mark_node;
6528 if (lvalue & clk_bitfield)
6530 expr = convert_bitfield_to_declared_type (expr);
6531 expr = fold_convert (type, expr);
6533 expr = build_target_expr_with_type (expr, type, complain);
6536 /* Take the address of the thing to which we will bind the
6538 expr = cp_build_addr_expr (expr, complain);
6539 if (expr == error_mark_node)
6540 return error_mark_node;
6542 /* Convert it to a pointer to the type referred to by the
6543 reference. This will adjust the pointer if a derived to
6544 base conversion is being performed. */
6545 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
6547 /* Convert the pointer to the desired reference type. */
6548 return build_nop (ref_type, expr);
6552 return decay_conversion (expr, complain);
6555 /* Warn about deprecated conversion if appropriate. */
6556 string_conv_p (totype, expr, 1);
6561 expr = convert_to_base (expr, totype, !c_cast_p,
6562 /*nonnull=*/false, complain);
6563 return build_nop (totype, expr);
6566 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
6567 c_cast_p, complain);
6573 if (convs->check_narrowing
6574 && !check_narrowing (totype, expr, complain))
6575 return error_mark_node;
6577 if (issue_conversion_warnings)
6578 expr = cp_convert_and_check (totype, expr, complain);
6580 expr = cp_convert (totype, expr, complain);
6585 /* ARG is being passed to a varargs function. Perform any conversions
6586 required. Return the converted value. */
6589 convert_arg_to_ellipsis (tree arg, tsubst_flags_t complain)
6592 location_t loc = EXPR_LOC_OR_LOC (arg, input_location);
6596 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6597 standard conversions are performed. */
6598 arg = decay_conversion (arg, complain);
6599 arg_type = TREE_TYPE (arg);
6602 If the argument has integral or enumeration type that is subject
6603 to the integral promotions (_conv.prom_), or a floating point
6604 type that is subject to the floating point promotion
6605 (_conv.fpprom_), the value of the argument is converted to the
6606 promoted type before the call. */
6607 if (TREE_CODE (arg_type) == REAL_TYPE
6608 && (TYPE_PRECISION (arg_type)
6609 < TYPE_PRECISION (double_type_node))
6610 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
6612 if ((complain & tf_warning)
6613 && warn_double_promotion && !c_inhibit_evaluation_warnings)
6614 warning_at (loc, OPT_Wdouble_promotion,
6615 "implicit conversion from %qT to %qT when passing "
6616 "argument to function",
6617 arg_type, double_type_node);
6618 arg = convert_to_real (double_type_node, arg);
6620 else if (NULLPTR_TYPE_P (arg_type))
6621 arg = null_pointer_node;
6622 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
6624 if (SCOPED_ENUM_P (arg_type))
6626 tree prom = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg,
6628 prom = cp_perform_integral_promotions (prom, complain);
6629 if (abi_version_crosses (6)
6630 && TYPE_MODE (TREE_TYPE (prom)) != TYPE_MODE (arg_type)
6631 && (complain & tf_warning))
6632 warning_at (loc, OPT_Wabi, "scoped enum %qT passed through ... as "
6633 "%qT before -fabi-version=6, %qT after", arg_type,
6634 TREE_TYPE (prom), ENUM_UNDERLYING_TYPE (arg_type));
6635 if (!abi_version_at_least (6))
6639 arg = cp_perform_integral_promotions (arg, complain);
6642 arg = require_complete_type_sfinae (arg, complain);
6643 arg_type = TREE_TYPE (arg);
6645 if (arg != error_mark_node
6646 /* In a template (or ill-formed code), we can have an incomplete type
6647 even after require_complete_type_sfinae, in which case we don't know
6648 whether it has trivial copy or not. */
6649 && COMPLETE_TYPE_P (arg_type))
6651 /* Build up a real lvalue-to-rvalue conversion in case the
6652 copy constructor is trivial but not callable. */
6653 if (!cp_unevaluated_operand && CLASS_TYPE_P (arg_type))
6654 force_rvalue (arg, complain);
6656 /* [expr.call] 5.2.2/7:
6657 Passing a potentially-evaluated argument of class type (Clause 9)
6658 with a non-trivial copy constructor or a non-trivial destructor
6659 with no corresponding parameter is conditionally-supported, with
6660 implementation-defined semantics.
6662 We support it as pass-by-invisible-reference, just like a normal
6665 If the call appears in the context of a sizeof expression,
6666 it is not potentially-evaluated. */
6667 if (cp_unevaluated_operand == 0
6668 && (type_has_nontrivial_copy_init (arg_type)
6669 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
6671 if (complain & tf_warning)
6672 warning (OPT_Wconditionally_supported,
6673 "passing objects of non-trivially-copyable "
6674 "type %q#T through %<...%> is conditionally supported",
6676 return cp_build_addr_expr (arg, complain);
6683 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6686 build_x_va_arg (source_location loc, tree expr, tree type)
6688 if (processing_template_decl)
6690 tree r = build_min (VA_ARG_EXPR, type, expr);
6691 SET_EXPR_LOCATION (r, loc);
6695 type = complete_type_or_else (type, NULL_TREE);
6697 if (expr == error_mark_node || !type)
6698 return error_mark_node;
6700 expr = mark_lvalue_use (expr);
6702 if (TREE_CODE (type) == REFERENCE_TYPE)
6704 error ("cannot receive reference type %qT through %<...%>", type);
6705 return error_mark_node;
6708 if (type_has_nontrivial_copy_init (type)
6709 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6711 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
6712 it as pass by invisible reference. */
6713 warning_at (loc, OPT_Wconditionally_supported,
6714 "receiving objects of non-trivially-copyable type %q#T "
6715 "through %<...%> is conditionally-supported", type);
6717 tree ref = cp_build_reference_type (type, false);
6718 expr = build_va_arg (loc, expr, ref);
6719 return convert_from_reference (expr);
6722 return build_va_arg (loc, expr, type);
6725 /* TYPE has been given to va_arg. Apply the default conversions which
6726 would have happened when passed via ellipsis. Return the promoted
6727 type, or the passed type if there is no change. */
6730 cxx_type_promotes_to (tree type)
6734 /* Perform the array-to-pointer and function-to-pointer
6736 type = type_decays_to (type);
6738 promote = type_promotes_to (type);
6739 if (same_type_p (type, promote))
6745 /* ARG is a default argument expression being passed to a parameter of
6746 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6747 zero-based argument number. Do any required conversions. Return
6748 the converted value. */
6750 static GTY(()) vec<tree, va_gc> *default_arg_context;
6752 push_defarg_context (tree fn)
6753 { vec_safe_push (default_arg_context, fn); }
6756 pop_defarg_context (void)
6757 { default_arg_context->pop (); }
6760 convert_default_arg (tree type, tree arg, tree fn, int parmnum,
6761 tsubst_flags_t complain)
6766 /* See through clones. */
6767 fn = DECL_ORIGIN (fn);
6769 /* Detect recursion. */
6770 FOR_EACH_VEC_SAFE_ELT (default_arg_context, i, t)
6773 if (complain & tf_error)
6774 error ("recursive evaluation of default argument for %q#D", fn);
6775 return error_mark_node;
6778 /* If the ARG is an unparsed default argument expression, the
6779 conversion cannot be performed. */
6780 if (TREE_CODE (arg) == DEFAULT_ARG)
6782 if (complain & tf_error)
6783 error ("call to %qD uses the default argument for parameter %P, which "
6784 "is not yet defined", fn, parmnum);
6785 return error_mark_node;
6788 push_defarg_context (fn);
6790 if (fn && DECL_TEMPLATE_INFO (fn))
6791 arg = tsubst_default_argument (fn, type, arg, complain);
6797 The names in the expression are bound, and the semantic
6798 constraints are checked, at the point where the default
6799 expressions appears.
6801 we must not perform access checks here. */
6802 push_deferring_access_checks (dk_no_check);
6803 /* We must make a copy of ARG, in case subsequent processing
6804 alters any part of it. */
6805 arg = break_out_target_exprs (arg);
6806 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6807 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6809 arg = convert_for_arg_passing (type, arg, complain);
6810 pop_deferring_access_checks();
6812 pop_defarg_context ();
6817 /* Returns the type which will really be used for passing an argument of
6821 type_passed_as (tree type)
6823 /* Pass classes with copy ctors by invisible reference. */
6824 if (TREE_ADDRESSABLE (type))
6826 type = build_reference_type (type);
6827 /* There are no other pointers to this temporary. */
6828 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
6830 else if (targetm.calls.promote_prototypes (type)
6831 && INTEGRAL_TYPE_P (type)
6832 && COMPLETE_TYPE_P (type)
6833 && tree_int_cst_lt (TYPE_SIZE (type), TYPE_SIZE (integer_type_node)))
6834 type = integer_type_node;
6839 /* Actually perform the appropriate conversion. */
6842 convert_for_arg_passing (tree type, tree val, tsubst_flags_t complain)
6846 /* If VAL is a bitfield, then -- since it has already been converted
6847 to TYPE -- it cannot have a precision greater than TYPE.
6849 If it has a smaller precision, we must widen it here. For
6850 example, passing "int f:3;" to a function expecting an "int" will
6851 not result in any conversion before this point.
6853 If the precision is the same we must not risk widening. For
6854 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6855 often have type "int", even though the C++ type for the field is
6856 "long long". If the value is being passed to a function
6857 expecting an "int", then no conversions will be required. But,
6858 if we call convert_bitfield_to_declared_type, the bitfield will
6859 be converted to "long long". */
6860 bitfield_type = is_bitfield_expr_with_lowered_type (val);
6862 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
6863 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
6865 if (val == error_mark_node)
6867 /* Pass classes with copy ctors by invisible reference. */
6868 else if (TREE_ADDRESSABLE (type))
6869 val = build1 (ADDR_EXPR, build_reference_type (type), val);
6870 else if (targetm.calls.promote_prototypes (type)
6871 && INTEGRAL_TYPE_P (type)
6872 && COMPLETE_TYPE_P (type)
6873 && tree_int_cst_lt (TYPE_SIZE (type), TYPE_SIZE (integer_type_node)))
6874 val = cp_perform_integral_promotions (val, complain);
6875 if ((complain & tf_warning)
6876 && warn_suggest_attribute_format)
6878 tree rhstype = TREE_TYPE (val);
6879 const enum tree_code coder = TREE_CODE (rhstype);
6880 const enum tree_code codel = TREE_CODE (type);
6881 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6883 && check_missing_format_attribute (type, rhstype))
6884 warning (OPT_Wsuggest_attribute_format,
6885 "argument of function call might be a candidate for a format attribute");
6890 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6891 which no conversions at all should be done. This is true for some
6892 builtins which don't act like normal functions. */
6895 magic_varargs_p (tree fn)
6897 if (flag_cilkplus && is_cilkplus_reduce_builtin (fn) != BUILT_IN_NONE)
6900 if (DECL_BUILT_IN (fn))
6901 switch (DECL_FUNCTION_CODE (fn))
6903 case BUILT_IN_CLASSIFY_TYPE:
6904 case BUILT_IN_CONSTANT_P:
6905 case BUILT_IN_NEXT_ARG:
6906 case BUILT_IN_VA_START:
6910 return lookup_attribute ("type generic",
6911 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
6917 /* Returns the decl of the dispatcher function if FN is a function version. */
6920 get_function_version_dispatcher (tree fn)
6922 tree dispatcher_decl = NULL;
6924 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6925 && DECL_FUNCTION_VERSIONED (fn));
6927 gcc_assert (targetm.get_function_versions_dispatcher);
6928 dispatcher_decl = targetm.get_function_versions_dispatcher (fn);
6930 if (dispatcher_decl == NULL)
6932 error_at (input_location, "use of multiversioned function "
6933 "without a default");
6937 retrofit_lang_decl (dispatcher_decl);
6938 gcc_assert (dispatcher_decl != NULL);
6939 return dispatcher_decl;
6942 /* fn is a function version dispatcher that is marked used. Mark all the
6943 semantically identical function versions it will dispatch as used. */
6946 mark_versions_used (tree fn)
6948 struct cgraph_node *node;
6949 struct cgraph_function_version_info *node_v;
6950 struct cgraph_function_version_info *it_v;
6952 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6954 node = cgraph_node::get (fn);
6958 gcc_assert (node->dispatcher_function);
6960 node_v = node->function_version ();
6964 /* All semantically identical versions are chained. Traverse and mark each
6965 one of them as used. */
6966 it_v = node_v->next;
6967 while (it_v != NULL)
6969 mark_used (it_v->this_node->decl);
6974 /* Build a call to "the copy constructor" for the type of A, even if it
6975 wouldn't be selected by normal overload resolution. Used for
6979 call_copy_ctor (tree a, tsubst_flags_t complain)
6981 tree ctype = TYPE_MAIN_VARIANT (TREE_TYPE (a));
6982 tree binfo = TYPE_BINFO (ctype);
6983 tree copy = get_copy_ctor (ctype, complain);
6984 copy = build_baselink (binfo, binfo, copy, NULL_TREE);
6985 tree ob = build_dummy_object (ctype);
6986 vec<tree, va_gc>* args = make_tree_vector_single (a);
6987 tree r = build_new_method_call (ob, copy, &args, NULL_TREE,
6988 LOOKUP_NORMAL, NULL, complain);
6989 release_tree_vector (args);
6993 /* Subroutine of the various build_*_call functions. Overload resolution
6994 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
6995 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
6996 bitmask of various LOOKUP_* flags which apply to the call itself. */
6999 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
7002 const vec<tree, va_gc> *args = cand->args;
7003 tree first_arg = cand->first_arg;
7004 conversion **convs = cand->convs;
7006 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
7011 unsigned int arg_index = 0;
7015 bool already_used = false;
7017 /* In a template, there is no need to perform all of the work that
7018 is normally done. We are only interested in the type of the call
7019 expression, i.e., the return type of the function. Any semantic
7020 errors will be deferred until the template is instantiated. */
7021 if (processing_template_decl)
7025 const tree *argarray;
7028 return_type = TREE_TYPE (TREE_TYPE (fn));
7029 nargs = vec_safe_length (args);
7030 if (first_arg == NULL_TREE)
7031 argarray = args->address ();
7039 alcarray = XALLOCAVEC (tree, nargs);
7040 alcarray[0] = build_this (first_arg);
7041 FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
7042 alcarray[ix + 1] = arg;
7043 argarray = alcarray;
7046 addr = build_addr_func (fn, complain);
7047 if (addr == error_mark_node)
7048 return error_mark_node;
7049 expr = build_call_array_loc (input_location, return_type,
7050 addr, nargs, argarray);
7051 if (TREE_THIS_VOLATILE (fn) && cfun)
7052 current_function_returns_abnormally = 1;
7053 return convert_from_reference (expr);
7056 /* Give any warnings we noticed during overload resolution. */
7057 if (cand->warnings && (complain & tf_warning))
7059 struct candidate_warning *w;
7060 for (w = cand->warnings; w; w = w->next)
7061 joust (cand, w->loser, 1, complain);
7064 /* Make =delete work with SFINAE. */
7065 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
7066 return error_mark_node;
7068 if (DECL_FUNCTION_MEMBER_P (fn))
7071 /* If FN is a template function, two cases must be considered.
7076 template <class T> void f();
7078 template <class T> struct B {
7082 struct C : A, B<int> {
7084 using B<int>::g; // #2
7087 In case #1 where `A::f' is a member template, DECL_ACCESS is
7088 recorded in the primary template but not in its specialization.
7089 We check access of FN using its primary template.
7091 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7092 because it is a member of class template B, DECL_ACCESS is
7093 recorded in the specialization `B<int>::g'. We cannot use its
7094 primary template because `B<T>::g' and `B<int>::g' may have
7095 different access. */
7096 if (DECL_TEMPLATE_INFO (fn)
7097 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
7098 access_fn = DECL_TI_TEMPLATE (fn);
7101 if (!perform_or_defer_access_check (cand->access_path, access_fn,
7103 return error_mark_node;
7106 /* If we're checking for implicit delete, don't bother with argument
7108 if (flags & LOOKUP_SPECULATIVE)
7110 if (DECL_DELETED_FN (fn))
7112 if (complain & tf_error)
7114 return error_mark_node;
7116 if (cand->viable == 1)
7118 else if (!(complain & tf_error))
7119 /* Reject bad conversions now. */
7120 return error_mark_node;
7121 /* else continue to get conversion error. */
7124 /* N3276 magic doesn't apply to nested calls. */
7125 int decltype_flag = (complain & tf_decltype);
7126 complain &= ~tf_decltype;
7128 /* Find maximum size of vector to hold converted arguments. */
7129 parmlen = list_length (parm);
7130 nargs = vec_safe_length (args) + (first_arg != NULL_TREE ? 1 : 0);
7131 if (parmlen > nargs)
7133 argarray = XALLOCAVEC (tree, nargs);
7135 /* The implicit parameters to a constructor are not considered by overload
7136 resolution, and must be of the proper type. */
7137 if (DECL_CONSTRUCTOR_P (fn))
7140 if (first_arg != NULL_TREE)
7142 object_arg = first_arg;
7143 first_arg = NULL_TREE;
7147 object_arg = (*args)[arg_index];
7150 argarray[j++] = build_this (object_arg);
7151 parm = TREE_CHAIN (parm);
7152 /* We should never try to call the abstract constructor. */
7153 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
7155 if (DECL_HAS_VTT_PARM_P (fn))
7157 argarray[j++] = (*args)[arg_index];
7159 parm = TREE_CHAIN (parm);
7162 /* Bypass access control for 'this' parameter. */
7163 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
7165 tree parmtype = TREE_VALUE (parm);
7166 tree arg = build_this (first_arg != NULL_TREE
7168 : (*args)[arg_index]);
7169 tree argtype = TREE_TYPE (arg);
7173 if (convs[i]->bad_p)
7175 if (complain & tf_error)
7177 if (permerror (input_location, "passing %qT as %<this%> "
7178 "argument discards qualifiers",
7179 TREE_TYPE (argtype)))
7180 inform (DECL_SOURCE_LOCATION (fn), " in call to %qD", fn);
7183 return error_mark_node;
7186 /* See if the function member or the whole class type is declared
7187 final and the call can be devirtualized. */
7188 if (DECL_FINAL_P (fn)
7189 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn))))
7190 flags |= LOOKUP_NONVIRTUAL;
7192 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
7193 X is called for an object that is not of type X, or of a type
7194 derived from X, the behavior is undefined.
7196 So we can assume that anything passed as 'this' is non-null, and
7197 optimize accordingly. */
7198 gcc_assert (TYPE_PTR_P (parmtype));
7199 /* Convert to the base in which the function was declared. */
7200 gcc_assert (cand->conversion_path != NULL_TREE);
7201 converted_arg = build_base_path (PLUS_EXPR,
7203 cand->conversion_path,
7205 /* Check that the base class is accessible. */
7206 if (!accessible_base_p (TREE_TYPE (argtype),
7207 BINFO_TYPE (cand->conversion_path), true))
7209 if (complain & tf_error)
7210 error ("%qT is not an accessible base of %qT",
7211 BINFO_TYPE (cand->conversion_path),
7212 TREE_TYPE (argtype));
7214 return error_mark_node;
7216 /* If fn was found by a using declaration, the conversion path
7217 will be to the derived class, not the base declaring fn. We
7218 must convert from derived to base. */
7219 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
7220 TREE_TYPE (parmtype), ba_unique,
7222 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
7223 base_binfo, 1, complain);
7225 argarray[j++] = converted_arg;
7226 parm = TREE_CHAIN (parm);
7227 if (first_arg != NULL_TREE)
7228 first_arg = NULL_TREE;
7235 gcc_assert (first_arg == NULL_TREE);
7236 for (; arg_index < vec_safe_length (args) && parm;
7237 parm = TREE_CHAIN (parm), ++arg_index, ++i)
7239 tree type = TREE_VALUE (parm);
7240 tree arg = (*args)[arg_index];
7241 bool conversion_warning = true;
7245 /* If the argument is NULL and used to (implicitly) instantiate a
7246 template function (and bind one of the template arguments to
7247 the type of 'long int'), we don't want to warn about passing NULL
7248 to non-pointer argument.
7249 For example, if we have this template function:
7251 template<typename T> void func(T x) {}
7253 we want to warn (when -Wconversion is enabled) in this case:
7259 but not in this case:
7265 if (arg == null_node
7266 && DECL_TEMPLATE_INFO (fn)
7267 && cand->template_decl
7268 && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS))
7269 conversion_warning = false;
7271 /* Warn about initializer_list deduction that isn't currently in the
7273 if (cxx_dialect > cxx98
7274 && flag_deduce_init_list
7275 && cand->template_decl
7276 && is_std_init_list (non_reference (type))
7277 && BRACE_ENCLOSED_INITIALIZER_P (arg))
7279 tree tmpl = TI_TEMPLATE (cand->template_decl);
7280 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
7281 tree patparm = get_pattern_parm (realparm, tmpl);
7282 tree pattype = TREE_TYPE (patparm);
7283 if (PACK_EXPANSION_P (pattype))
7284 pattype = PACK_EXPANSION_PATTERN (pattype);
7285 pattype = non_reference (pattype);
7287 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
7288 && (cand->explicit_targs == NULL_TREE
7289 || (TREE_VEC_LENGTH (cand->explicit_targs)
7290 <= TEMPLATE_TYPE_IDX (pattype))))
7292 pedwarn (input_location, 0, "deducing %qT as %qT",
7293 non_reference (TREE_TYPE (patparm)),
7294 non_reference (type));
7295 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
7296 pedwarn (input_location, 0,
7297 " (you can disable this with -fno-deduce-init-list)");
7300 val = convert_like_with_context (conv, arg, fn, i - is_method,
7303 : complain & (~tf_warning));
7305 val = convert_for_arg_passing (type, val, complain);
7307 if (val == error_mark_node)
7308 return error_mark_node;
7310 argarray[j++] = val;
7313 /* Default arguments */
7314 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
7316 if (TREE_VALUE (parm) == error_mark_node)
7317 return error_mark_node;
7318 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
7319 TREE_PURPOSE (parm),
7325 for (; arg_index < vec_safe_length (args); ++arg_index)
7327 tree a = (*args)[arg_index];
7328 if (magic_varargs_p (fn))
7329 /* Do no conversions for magic varargs. */
7330 a = mark_type_use (a);
7331 else if (DECL_CONSTRUCTOR_P (fn)
7332 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn),
7335 /* Avoid infinite recursion trying to call A(...). */
7336 if (complain & tf_error)
7337 /* Try to call the actual copy constructor for a good error. */
7338 call_copy_ctor (a, complain);
7339 return error_mark_node;
7342 a = convert_arg_to_ellipsis (a, complain);
7346 gcc_assert (j <= nargs);
7349 check_function_arguments (TREE_TYPE (fn), nargs, argarray);
7351 /* Avoid actually calling copy constructors and copy assignment operators,
7354 if (! flag_elide_constructors)
7355 /* Do things the hard way. */;
7356 else if (cand->num_convs == 1
7357 && (DECL_COPY_CONSTRUCTOR_P (fn)
7358 || DECL_MOVE_CONSTRUCTOR_P (fn))
7359 /* It's unsafe to elide the constructor when handling
7360 a noexcept-expression, it may evaluate to the wrong
7361 value (c++/53025). */
7362 && cp_noexcept_operand == 0)
7365 tree arg = argarray[num_artificial_parms_for (fn)];
7367 bool trivial = trivial_fn_p (fn);
7369 /* Pull out the real argument, disregarding const-correctness. */
7371 while (CONVERT_EXPR_P (targ)
7372 || TREE_CODE (targ) == NON_LVALUE_EXPR)
7373 targ = TREE_OPERAND (targ, 0);
7374 if (TREE_CODE (targ) == ADDR_EXPR)
7376 targ = TREE_OPERAND (targ, 0);
7377 if (!same_type_ignoring_top_level_qualifiers_p
7378 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
7387 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
7389 /* [class.copy]: the copy constructor is implicitly defined even if
7390 the implementation elided its use. */
7391 if (!trivial || DECL_DELETED_FN (fn))
7394 already_used = true;
7397 /* If we're creating a temp and we already have one, don't create a
7398 new one. If we're not creating a temp but we get one, use
7399 INIT_EXPR to collapse the temp into our target. Otherwise, if the
7400 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
7401 temp or an INIT_EXPR otherwise. */
7403 if (is_dummy_object (fa))
7405 if (TREE_CODE (arg) == TARGET_EXPR)
7408 return force_target_expr (DECL_CONTEXT (fn), arg, complain);
7410 else if (TREE_CODE (arg) == TARGET_EXPR || trivial)
7412 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
7415 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
7419 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
7420 && trivial_fn_p (fn)
7421 && !DECL_DELETED_FN (fn))
7423 tree to = stabilize_reference
7424 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
7425 tree type = TREE_TYPE (to);
7426 tree as_base = CLASSTYPE_AS_BASE (type);
7427 tree arg = argarray[1];
7429 if (is_really_empty_class (type))
7431 /* Avoid copying empty classes. */
7432 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
7433 TREE_NO_WARNING (val) = 1;
7434 val = build2 (COMPOUND_EXPR, type, val, to);
7435 TREE_NO_WARNING (val) = 1;
7437 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
7439 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
7440 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
7444 /* We must only copy the non-tail padding parts. */
7446 tree array_type, alias_set;
7448 arg2 = TYPE_SIZE_UNIT (as_base);
7449 arg0 = cp_build_addr_expr (to, complain);
7451 array_type = build_array_type (char_type_node,
7453 (size_binop (MINUS_EXPR,
7454 arg2, size_int (1))));
7455 alias_set = build_int_cst (build_pointer_type (type), 0);
7456 t = build2 (MODIFY_EXPR, void_type_node,
7457 build2 (MEM_REF, array_type, arg0, alias_set),
7458 build2 (MEM_REF, array_type, arg, alias_set));
7459 val = build2 (COMPOUND_EXPR, TREE_TYPE (to), t, to);
7460 TREE_NO_WARNING (val) = 1;
7465 else if (DECL_DESTRUCTOR_P (fn)
7466 && trivial_fn_p (fn)
7467 && !DECL_DELETED_FN (fn))
7468 return fold_convert (void_type_node, argarray[0]);
7469 /* FIXME handle trivial default constructor, too. */
7471 /* For calls to a multi-versioned function, overload resolution
7472 returns the function with the highest target priority, that is,
7473 the version that will checked for dispatching first. If this
7474 version is inlinable, a direct call to this version can be made
7475 otherwise the call should go through the dispatcher. */
7477 if (DECL_FUNCTION_VERSIONED (fn)
7478 && (current_function_decl == NULL
7479 || !targetm.target_option.can_inline_p (current_function_decl, fn)))
7481 fn = get_function_version_dispatcher (fn);
7485 mark_versions_used (fn);
7489 && !mark_used (fn, complain))
7490 return error_mark_node;
7492 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0
7493 /* Don't mess with virtual lookup in instantiate_non_dependent_expr;
7494 virtual functions can't be constexpr. */
7495 && !in_template_function ())
7498 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
7500 ba_any, NULL, complain);
7501 gcc_assert (binfo && binfo != error_mark_node);
7503 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1,
7505 if (TREE_SIDE_EFFECTS (argarray[0]))
7506 argarray[0] = save_expr (argarray[0]);
7507 t = build_pointer_type (TREE_TYPE (fn));
7508 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
7509 fn = build_java_interface_fn_ref (fn, argarray[0]);
7511 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
7516 fn = build_addr_func (fn, complain);
7517 if (fn == error_mark_node)
7518 return error_mark_node;
7521 tree call = build_cxx_call (fn, nargs, argarray, complain|decltype_flag);
7522 if (TREE_CODE (call) == CALL_EXPR
7523 && (cand->flags & LOOKUP_LIST_INIT_CTOR))
7524 CALL_EXPR_LIST_INIT_P (call) = true;
7528 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
7529 This function performs no overload resolution, conversion, or other
7530 high-level operations. */
7533 build_cxx_call (tree fn, int nargs, tree *argarray,
7534 tsubst_flags_t complain)
7539 /* Remember roughly where this call is. */
7540 location_t loc = EXPR_LOC_OR_LOC (fn, input_location);
7541 fn = build_call_a (fn, nargs, argarray);
7542 SET_EXPR_LOCATION (fn, loc);
7544 fndecl = get_callee_fndecl (fn);
7546 /* Check that arguments to builtin functions match the expectations. */
7548 && DECL_BUILT_IN (fndecl)
7549 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
7550 && !check_builtin_function_arguments (fndecl, nargs, argarray))
7551 return error_mark_node;
7553 /* If it is a built-in array notation function, then the return type of
7554 the function is the element type of the array passed in as array
7555 notation (i.e. the first parameter of the function). */
7556 if (flag_cilkplus && TREE_CODE (fn) == CALL_EXPR)
7558 enum built_in_function bif =
7559 is_cilkplus_reduce_builtin (CALL_EXPR_FN (fn));
7560 if (bif == BUILT_IN_CILKPLUS_SEC_REDUCE_ADD
7561 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MUL
7562 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MAX
7563 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MIN
7564 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE
7565 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MUTATING)
7567 if (call_expr_nargs (fn) == 0)
7569 error_at (EXPR_LOCATION (fn), "Invalid builtin arguments");
7570 return error_mark_node;
7572 /* for bif == BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_ZERO or
7573 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_ZERO or
7574 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_NONZERO or
7575 BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_NONZERO or
7576 BUILT_IN_CILKPLUS_SEC_REDUCE_MIN_IND or
7577 BUILT_IN_CILKPLUS_SEC_REDUCE_MAX_IND
7578 The pre-defined return-type is the correct one. */
7579 tree array_ntn = CALL_EXPR_ARG (fn, 0);
7580 TREE_TYPE (fn) = TREE_TYPE (array_ntn);
7585 /* Some built-in function calls will be evaluated at compile-time in
7586 fold (). Set optimize to 1 when folding __builtin_constant_p inside
7587 a constexpr function so that fold_builtin_1 doesn't fold it to 0. */
7588 optimize_sav = optimize;
7589 if (!optimize && fndecl && DECL_IS_BUILTIN_CONSTANT_P (fndecl)
7590 && current_function_decl
7591 && DECL_DECLARED_CONSTEXPR_P (current_function_decl))
7593 fn = fold_if_not_in_template (fn);
7594 optimize = optimize_sav;
7596 if (VOID_TYPE_P (TREE_TYPE (fn)))
7599 /* 5.2.2/11: If a function call is a prvalue of object type: if the
7600 function call is either the operand of a decltype-specifier or the
7601 right operand of a comma operator that is the operand of a
7602 decltype-specifier, a temporary object is not introduced for the
7603 prvalue. The type of the prvalue may be incomplete. */
7604 if (!(complain & tf_decltype))
7606 fn = require_complete_type_sfinae (fn, complain);
7607 if (fn == error_mark_node)
7608 return error_mark_node;
7610 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
7611 fn = build_cplus_new (TREE_TYPE (fn), fn, complain);
7613 return convert_from_reference (fn);
7616 static GTY(()) tree java_iface_lookup_fn;
7618 /* Make an expression which yields the address of the Java interface
7619 method FN. This is achieved by generating a call to libjava's
7620 _Jv_LookupInterfaceMethodIdx(). */
7623 build_java_interface_fn_ref (tree fn, tree instance)
7625 tree lookup_fn, method, idx;
7626 tree klass_ref, iface, iface_ref;
7629 if (!java_iface_lookup_fn)
7631 tree ftype = build_function_type_list (ptr_type_node,
7632 ptr_type_node, ptr_type_node,
7633 java_int_type_node, NULL_TREE);
7634 java_iface_lookup_fn
7635 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
7636 0, NOT_BUILT_IN, NULL, NULL_TREE);
7639 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
7640 This is the first entry in the vtable. */
7641 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
7642 tf_warning_or_error),
7645 /* Get the java.lang.Class pointer for the interface being called. */
7646 iface = DECL_CONTEXT (fn);
7647 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
7648 if (!iface_ref || !VAR_P (iface_ref)
7649 || DECL_CONTEXT (iface_ref) != iface)
7651 error ("could not find class$ field in java interface type %qT",
7653 return error_mark_node;
7655 iface_ref = build_address (iface_ref);
7656 iface_ref = convert (build_pointer_type (iface), iface_ref);
7658 /* Determine the itable index of FN. */
7660 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
7662 if (!DECL_VIRTUAL_P (method))
7668 idx = build_int_cst (NULL_TREE, i);
7670 lookup_fn = build1 (ADDR_EXPR,
7671 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
7672 java_iface_lookup_fn);
7673 return build_call_nary (ptr_type_node, lookup_fn,
7674 3, klass_ref, iface_ref, idx);
7677 /* Returns the value to use for the in-charge parameter when making a
7678 call to a function with the indicated NAME.
7680 FIXME:Can't we find a neater way to do this mapping? */
7683 in_charge_arg_for_name (tree name)
7685 if (name == base_ctor_identifier
7686 || name == base_dtor_identifier)
7687 return integer_zero_node;
7688 else if (name == complete_ctor_identifier)
7689 return integer_one_node;
7690 else if (name == complete_dtor_identifier)
7691 return integer_two_node;
7692 else if (name == deleting_dtor_identifier)
7693 return integer_three_node;
7695 /* This function should only be called with one of the names listed
7701 /* Build a call to a constructor, destructor, or an assignment
7702 operator for INSTANCE, an expression with class type. NAME
7703 indicates the special member function to call; *ARGS are the
7704 arguments. ARGS may be NULL. This may change ARGS. BINFO
7705 indicates the base of INSTANCE that is to be passed as the `this'
7706 parameter to the member function called.
7708 FLAGS are the LOOKUP_* flags to use when processing the call.
7710 If NAME indicates a complete object constructor, INSTANCE may be
7711 NULL_TREE. In this case, the caller will call build_cplus_new to
7712 store the newly constructed object into a VAR_DECL. */
7715 build_special_member_call (tree instance, tree name, vec<tree, va_gc> **args,
7716 tree binfo, int flags, tsubst_flags_t complain)
7719 /* The type of the subobject to be constructed or destroyed. */
7721 vec<tree, va_gc> *allocated = NULL;
7724 gcc_assert (name == complete_ctor_identifier
7725 || name == base_ctor_identifier
7726 || name == complete_dtor_identifier
7727 || name == base_dtor_identifier
7728 || name == deleting_dtor_identifier
7729 || name == ansi_assopname (NOP_EXPR));
7732 /* Resolve the name. */
7733 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
7734 return error_mark_node;
7736 binfo = TYPE_BINFO (binfo);
7739 gcc_assert (binfo != NULL_TREE);
7741 class_type = BINFO_TYPE (binfo);
7743 /* Handle the special case where INSTANCE is NULL_TREE. */
7744 if (name == complete_ctor_identifier && !instance)
7745 instance = build_dummy_object (class_type);
7748 if (name == complete_dtor_identifier
7749 || name == base_dtor_identifier
7750 || name == deleting_dtor_identifier)
7751 gcc_assert (args == NULL || vec_safe_is_empty (*args));
7753 /* Convert to the base class, if necessary. */
7754 if (!same_type_ignoring_top_level_qualifiers_p
7755 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
7757 if (name != ansi_assopname (NOP_EXPR))
7758 /* For constructors and destructors, either the base is
7759 non-virtual, or it is virtual but we are doing the
7760 conversion from a constructor or destructor for the
7761 complete object. In either case, we can convert
7763 instance = convert_to_base_statically (instance, binfo);
7765 /* However, for assignment operators, we must convert
7766 dynamically if the base is virtual. */
7767 instance = build_base_path (PLUS_EXPR, instance,
7768 binfo, /*nonnull=*/1, complain);
7772 gcc_assert (instance != NULL_TREE);
7774 fns = lookup_fnfields (binfo, name, 1);
7776 /* When making a call to a constructor or destructor for a subobject
7777 that uses virtual base classes, pass down a pointer to a VTT for
7779 if ((name == base_ctor_identifier
7780 || name == base_dtor_identifier)
7781 && CLASSTYPE_VBASECLASSES (class_type))
7786 /* If the current function is a complete object constructor
7787 or destructor, then we fetch the VTT directly.
7788 Otherwise, we look it up using the VTT we were given. */
7789 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
7790 vtt = decay_conversion (vtt, complain);
7791 if (vtt == error_mark_node)
7792 return error_mark_node;
7793 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
7794 build2 (EQ_EXPR, boolean_type_node,
7795 current_in_charge_parm, integer_zero_node),
7798 if (BINFO_SUBVTT_INDEX (binfo))
7799 sub_vtt = fold_build_pointer_plus (vtt, BINFO_SUBVTT_INDEX (binfo));
7805 allocated = make_tree_vector ();
7809 vec_safe_insert (*args, 0, sub_vtt);
7812 ret = build_new_method_call (instance, fns, args,
7813 TYPE_BINFO (BINFO_TYPE (binfo)),
7817 if (allocated != NULL)
7818 release_tree_vector (allocated);
7820 if ((complain & tf_error)
7821 && (flags & LOOKUP_DELEGATING_CONS)
7822 && name == complete_ctor_identifier
7823 && TREE_CODE (ret) == CALL_EXPR
7824 && (DECL_ABSTRACT_ORIGIN (TREE_OPERAND (CALL_EXPR_FN (ret), 0))
7825 == current_function_decl))
7826 error ("constructor delegates to itself");
7831 /* Return the NAME, as a C string. The NAME indicates a function that
7832 is a member of TYPE. *FREE_P is set to true if the caller must
7833 free the memory returned.
7835 Rather than go through all of this, we should simply set the names
7836 of constructors and destructors appropriately, and dispense with
7837 ctor_identifier, dtor_identifier, etc. */
7840 name_as_c_string (tree name, tree type, bool *free_p)
7844 /* Assume that we will not allocate memory. */
7846 /* Constructors and destructors are special. */
7847 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7850 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
7851 /* For a destructor, add the '~'. */
7852 if (name == complete_dtor_identifier
7853 || name == base_dtor_identifier
7854 || name == deleting_dtor_identifier)
7856 pretty_name = concat ("~", pretty_name, NULL);
7857 /* Remember that we need to free the memory allocated. */
7861 else if (IDENTIFIER_TYPENAME_P (name))
7863 pretty_name = concat ("operator ",
7864 type_as_string_translate (TREE_TYPE (name),
7865 TFF_PLAIN_IDENTIFIER),
7867 /* Remember that we need to free the memory allocated. */
7871 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
7876 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
7877 be set, upon return, to the function called. ARGS may be NULL.
7878 This may change ARGS. */
7881 build_new_method_call_1 (tree instance, tree fns, vec<tree, va_gc> **args,
7882 tree conversion_path, int flags,
7883 tree *fn_p, tsubst_flags_t complain)
7885 struct z_candidate *candidates = 0, *cand;
7886 tree explicit_targs = NULL_TREE;
7887 tree basetype = NULL_TREE;
7888 tree access_binfo, binfo;
7890 tree first_mem_arg = NULL_TREE;
7892 bool skip_first_for_error;
7893 vec<tree, va_gc> *user_args;
7896 int template_only = 0;
7900 vec<tree, va_gc> *orig_args = NULL;
7903 gcc_assert (instance != NULL_TREE);
7905 /* We don't know what function we're going to call, yet. */
7909 if (error_operand_p (instance)
7910 || !fns || error_operand_p (fns))
7911 return error_mark_node;
7913 if (!BASELINK_P (fns))
7915 if (complain & tf_error)
7916 error ("call to non-function %qD", fns);
7917 return error_mark_node;
7920 orig_instance = instance;
7923 /* Dismantle the baselink to collect all the information we need. */
7924 if (!conversion_path)
7925 conversion_path = BASELINK_BINFO (fns);
7926 access_binfo = BASELINK_ACCESS_BINFO (fns);
7927 binfo = BASELINK_BINFO (fns);
7928 optype = BASELINK_OPTYPE (fns);
7929 fns = BASELINK_FUNCTIONS (fns);
7930 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7932 explicit_targs = TREE_OPERAND (fns, 1);
7933 fns = TREE_OPERAND (fns, 0);
7936 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
7937 || TREE_CODE (fns) == TEMPLATE_DECL
7938 || TREE_CODE (fns) == OVERLOAD);
7939 fn = get_first_fn (fns);
7940 name = DECL_NAME (fn);
7942 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
7943 gcc_assert (CLASS_TYPE_P (basetype));
7945 if (processing_template_decl)
7947 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
7948 instance = build_non_dependent_expr (instance);
7950 make_args_non_dependent (*args);
7953 user_args = args == NULL ? NULL : *args;
7954 /* Under DR 147 A::A() is an invalid constructor call,
7955 not a functional cast. */
7956 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
7958 if (! (complain & tf_error))
7959 return error_mark_node;
7961 if (permerror (input_location,
7962 "cannot call constructor %<%T::%D%> directly",
7964 inform (input_location, "for a function-style cast, remove the "
7965 "redundant %<::%D%>", name);
7966 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
7971 /* Figure out whether to skip the first argument for the error
7972 message we will display to users if an error occurs. We don't
7973 want to display any compiler-generated arguments. The "this"
7974 pointer hasn't been added yet. However, we must remove the VTT
7975 pointer if this is a call to a base-class constructor or
7977 skip_first_for_error = false;
7978 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7980 /* Callers should explicitly indicate whether they want to construct
7981 the complete object or just the part without virtual bases. */
7982 gcc_assert (name != ctor_identifier);
7983 /* Similarly for destructors. */
7984 gcc_assert (name != dtor_identifier);
7985 /* Remove the VTT pointer, if present. */
7986 if ((name == base_ctor_identifier || name == base_dtor_identifier)
7987 && CLASSTYPE_VBASECLASSES (basetype))
7988 skip_first_for_error = true;
7991 /* Process the argument list. */
7992 if (args != NULL && *args != NULL)
7994 *args = resolve_args (*args, complain);
7996 return error_mark_node;
7999 /* Consider the object argument to be used even if we end up selecting a
8000 static member function. */
8001 instance = mark_type_use (instance);
8003 /* It's OK to call destructors and constructors on cv-qualified objects.
8004 Therefore, convert the INSTANCE to the unqualified type, if
8006 if (DECL_DESTRUCTOR_P (fn)
8007 || DECL_CONSTRUCTOR_P (fn))
8009 if (!same_type_p (basetype, TREE_TYPE (instance)))
8011 instance = build_this (instance);
8012 instance = build_nop (build_pointer_type (basetype), instance);
8013 instance = build_fold_indirect_ref (instance);
8016 if (DECL_DESTRUCTOR_P (fn))
8017 name = complete_dtor_identifier;
8019 /* For the overload resolution we need to find the actual `this`
8020 that would be captured if the call turns out to be to a
8021 non-static member function. Do not actually capture it at this
8023 if (DECL_CONSTRUCTOR_P (fn))
8024 /* Constructors don't use the enclosing 'this'. */
8025 first_mem_arg = instance;
8027 first_mem_arg = maybe_resolve_dummy (instance, false);
8029 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8030 p = conversion_obstack_alloc (0);
8032 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
8033 initializer, not T({ }). */
8034 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !vec_safe_is_empty (*args)
8035 && DIRECT_LIST_INIT_P ((**args)[0]))
8037 tree init_list = (**args)[0];
8038 tree init = NULL_TREE;
8040 gcc_assert ((*args)->length () == 1
8041 && !(flags & LOOKUP_ONLYCONVERTING));
8043 /* If the initializer list has no elements and T is a class type with
8044 a default constructor, the object is value-initialized. Handle
8045 this here so we don't need to handle it wherever we use
8046 build_special_member_call. */
8047 if (CONSTRUCTOR_NELTS (init_list) == 0
8048 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
8049 /* For a user-provided default constructor, use the normal
8050 mechanisms so that protected access works. */
8051 && type_has_non_user_provided_default_constructor (basetype)
8052 && !processing_template_decl)
8053 init = build_value_init (basetype, complain);
8055 /* If BASETYPE is an aggregate, we need to do aggregate
8057 else if (CP_AGGREGATE_TYPE_P (basetype))
8058 init = digest_init (basetype, init_list, complain);
8062 if (is_dummy_object (instance))
8063 return get_target_expr_sfinae (init, complain);
8064 init = build2 (INIT_EXPR, TREE_TYPE (instance), instance, init);
8065 TREE_SIDE_EFFECTS (init) = true;
8069 /* Otherwise go ahead with overload resolution. */
8070 add_list_candidates (fns, first_mem_arg, init_list,
8071 basetype, explicit_targs, template_only,
8072 conversion_path, access_binfo, flags,
8073 &candidates, complain);
8077 add_candidates (fns, first_mem_arg, user_args, optype,
8078 explicit_targs, template_only, conversion_path,
8079 access_binfo, flags, &candidates, complain);
8081 any_viable_p = false;
8082 candidates = splice_viable (candidates, false, &any_viable_p);
8086 if (complain & tf_error)
8088 if (!COMPLETE_OR_OPEN_TYPE_P (basetype))
8089 cxx_incomplete_type_error (instance, basetype);
8091 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
8092 basetype, optype, build_tree_list_vec (user_args),
8093 TREE_TYPE (instance));
8100 pretty_name = name_as_c_string (name, basetype, &free_p);
8101 arglist = build_tree_list_vec (user_args);
8102 if (skip_first_for_error)
8103 arglist = TREE_CHAIN (arglist);
8104 error ("no matching function for call to %<%T::%s(%A)%#V%>",
8105 basetype, pretty_name, arglist,
8106 TREE_TYPE (instance));
8110 print_z_candidates (location_of (name), candidates);
8112 call = error_mark_node;
8116 cand = tourney (candidates, complain);
8123 if (complain & tf_error)
8125 pretty_name = name_as_c_string (name, basetype, &free_p);
8126 arglist = build_tree_list_vec (user_args);
8127 if (skip_first_for_error)
8128 arglist = TREE_CHAIN (arglist);
8129 if (!any_strictly_viable (candidates))
8130 error ("no matching function for call to %<%s(%A)%>",
8131 pretty_name, arglist);
8133 error ("call of overloaded %<%s(%A)%> is ambiguous",
8134 pretty_name, arglist);
8135 print_z_candidates (location_of (name), candidates);
8139 call = error_mark_node;
8146 if (!(flags & LOOKUP_NONVIRTUAL)
8147 && DECL_PURE_VIRTUAL_P (fn)
8148 && instance == current_class_ref
8149 && (complain & tf_warning))
8151 /* This is not an error, it is runtime undefined
8153 if (!current_function_decl)
8154 warning (0, "pure virtual %q#D called from "
8155 "non-static data member initializer", fn);
8156 else if (DECL_CONSTRUCTOR_P (current_function_decl)
8157 || DECL_DESTRUCTOR_P (current_function_decl))
8158 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl)
8159 ? "pure virtual %q#D called from constructor"
8160 : "pure virtual %q#D called from destructor"),
8164 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
8165 && !DECL_CONSTRUCTOR_P (fn)
8166 && is_dummy_object (instance))
8168 instance = maybe_resolve_dummy (instance, true);
8169 if (instance == error_mark_node)
8170 call = error_mark_node;
8171 else if (!is_dummy_object (instance))
8173 /* We captured 'this' in the current lambda now that
8174 we know we really need it. */
8175 cand->first_arg = instance;
8179 if (complain & tf_error)
8180 error ("cannot call member function %qD without object",
8182 call = error_mark_node;
8186 if (call != error_mark_node)
8188 /* Optimize away vtable lookup if we know that this
8189 function can't be overridden. We need to check if
8190 the context and the type where we found fn are the same,
8191 actually FN might be defined in a different class
8192 type because of a using-declaration. In this case, we
8193 do not want to perform a non-virtual call. */
8194 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
8195 && same_type_ignoring_top_level_qualifiers_p
8196 (DECL_CONTEXT (fn), BINFO_TYPE (binfo))
8197 && resolves_to_fixed_type_p (instance, 0))
8198 flags |= LOOKUP_NONVIRTUAL;
8200 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
8201 /* Now we know what function is being called. */
8204 /* Build the actual CALL_EXPR. */
8205 call = build_over_call (cand, flags, complain);
8206 /* In an expression of the form `a->f()' where `f' turns
8207 out to be a static member function, `a' is
8208 none-the-less evaluated. */
8209 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
8210 && !is_dummy_object (instance)
8211 && TREE_SIDE_EFFECTS (instance))
8212 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
8214 else if (call != error_mark_node
8215 && DECL_DESTRUCTOR_P (cand->fn)
8216 && !VOID_TYPE_P (TREE_TYPE (call)))
8217 /* An explicit call of the form "x->~X()" has type
8218 "void". However, on platforms where destructors
8219 return "this" (i.e., those where
8220 targetm.cxx.cdtor_returns_this is true), such calls
8221 will appear to have a return value of pointer type
8222 to the low-level call machinery. We do not want to
8223 change the low-level machinery, since we want to be
8224 able to optimize "delete f()" on such platforms as
8225 "operator delete(~X(f()))" (rather than generating
8226 "t = f(), ~X(t), operator delete (t)"). */
8227 call = build_nop (void_type_node, call);
8232 if (processing_template_decl && call != error_mark_node)
8234 bool cast_to_void = false;
8236 if (TREE_CODE (call) == COMPOUND_EXPR)
8237 call = TREE_OPERAND (call, 1);
8238 else if (TREE_CODE (call) == NOP_EXPR)
8240 cast_to_void = true;
8241 call = TREE_OPERAND (call, 0);
8243 if (INDIRECT_REF_P (call))
8244 call = TREE_OPERAND (call, 0);
8245 call = (build_min_non_dep_call_vec
8247 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
8248 orig_instance, orig_fns, NULL_TREE),
8250 SET_EXPR_LOCATION (call, input_location);
8251 call = convert_from_reference (call);
8253 call = build_nop (void_type_node, call);
8256 /* Free all the conversions we allocated. */
8257 obstack_free (&conversion_obstack, p);
8259 if (orig_args != NULL)
8260 release_tree_vector (orig_args);
8265 /* Wrapper for above. */
8268 build_new_method_call (tree instance, tree fns, vec<tree, va_gc> **args,
8269 tree conversion_path, int flags,
8270 tree *fn_p, tsubst_flags_t complain)
8273 bool subtime = timevar_cond_start (TV_OVERLOAD);
8274 ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags,
8276 timevar_cond_stop (TV_OVERLOAD, subtime);
8280 /* Returns true iff standard conversion sequence ICS1 is a proper
8281 subsequence of ICS2. */
8284 is_subseq (conversion *ics1, conversion *ics2)
8286 /* We can assume that a conversion of the same code
8287 between the same types indicates a subsequence since we only get
8288 here if the types we are converting from are the same. */
8290 while (ics1->kind == ck_rvalue
8291 || ics1->kind == ck_lvalue)
8292 ics1 = next_conversion (ics1);
8296 while (ics2->kind == ck_rvalue
8297 || ics2->kind == ck_lvalue)
8298 ics2 = next_conversion (ics2);
8300 if (ics2->kind == ck_user
8301 || ics2->kind == ck_ambig
8302 || ics2->kind == ck_aggr
8303 || ics2->kind == ck_list
8304 || ics2->kind == ck_identity)
8305 /* At this point, ICS1 cannot be a proper subsequence of
8306 ICS2. We can get a USER_CONV when we are comparing the
8307 second standard conversion sequence of two user conversion
8311 ics2 = next_conversion (ics2);
8313 if (ics2->kind == ics1->kind
8314 && same_type_p (ics2->type, ics1->type)
8315 && same_type_p (next_conversion (ics2)->type,
8316 next_conversion (ics1)->type))
8321 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
8322 be any _TYPE nodes. */
8325 is_properly_derived_from (tree derived, tree base)
8327 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
8330 /* We only allow proper derivation here. The DERIVED_FROM_P macro
8331 considers every class derived from itself. */
8332 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
8333 && DERIVED_FROM_P (base, derived));
8336 /* We build the ICS for an implicit object parameter as a pointer
8337 conversion sequence. However, such a sequence should be compared
8338 as if it were a reference conversion sequence. If ICS is the
8339 implicit conversion sequence for an implicit object parameter,
8340 modify it accordingly. */
8343 maybe_handle_implicit_object (conversion **ics)
8347 /* [over.match.funcs]
8349 For non-static member functions, the type of the
8350 implicit object parameter is "reference to cv X"
8351 where X is the class of which the function is a
8352 member and cv is the cv-qualification on the member
8353 function declaration. */
8354 conversion *t = *ics;
8355 tree reference_type;
8357 /* The `this' parameter is a pointer to a class type. Make the
8358 implicit conversion talk about a reference to that same class
8360 reference_type = TREE_TYPE (t->type);
8361 reference_type = build_reference_type (reference_type);
8363 if (t->kind == ck_qual)
8364 t = next_conversion (t);
8365 if (t->kind == ck_ptr)
8366 t = next_conversion (t);
8367 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
8368 t = direct_reference_binding (reference_type, t);
8370 t->rvaluedness_matches_p = 0;
8375 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
8376 and return the initial reference binding conversion. Otherwise,
8377 leave *ICS unchanged and return NULL. */
8380 maybe_handle_ref_bind (conversion **ics)
8382 if ((*ics)->kind == ck_ref_bind)
8384 conversion *old_ics = *ics;
8385 *ics = next_conversion (old_ics);
8386 (*ics)->user_conv_p = old_ics->user_conv_p;
8393 /* Compare two implicit conversion sequences according to the rules set out in
8394 [over.ics.rank]. Return values:
8396 1: ics1 is better than ics2
8397 -1: ics2 is better than ics1
8398 0: ics1 and ics2 are indistinguishable */
8401 compare_ics (conversion *ics1, conversion *ics2)
8407 tree deref_from_type1 = NULL_TREE;
8408 tree deref_from_type2 = NULL_TREE;
8409 tree deref_to_type1 = NULL_TREE;
8410 tree deref_to_type2 = NULL_TREE;
8411 conversion_rank rank1, rank2;
8413 /* REF_BINDING is nonzero if the result of the conversion sequence
8414 is a reference type. In that case REF_CONV is the reference
8415 binding conversion. */
8416 conversion *ref_conv1;
8417 conversion *ref_conv2;
8419 /* Compare badness before stripping the reference conversion. */
8420 if (ics1->bad_p > ics2->bad_p)
8422 else if (ics1->bad_p < ics2->bad_p)
8425 /* Handle implicit object parameters. */
8426 maybe_handle_implicit_object (&ics1);
8427 maybe_handle_implicit_object (&ics2);
8429 /* Handle reference parameters. */
8430 ref_conv1 = maybe_handle_ref_bind (&ics1);
8431 ref_conv2 = maybe_handle_ref_bind (&ics2);
8433 /* List-initialization sequence L1 is a better conversion sequence than
8434 list-initialization sequence L2 if L1 converts to
8435 std::initializer_list<X> for some X and L2 does not. */
8436 if (ics1->kind == ck_list && ics2->kind != ck_list)
8438 if (ics2->kind == ck_list && ics1->kind != ck_list)
8443 When comparing the basic forms of implicit conversion sequences (as
8444 defined in _over.best.ics_)
8446 --a standard conversion sequence (_over.ics.scs_) is a better
8447 conversion sequence than a user-defined conversion sequence
8448 or an ellipsis conversion sequence, and
8450 --a user-defined conversion sequence (_over.ics.user_) is a
8451 better conversion sequence than an ellipsis conversion sequence
8452 (_over.ics.ellipsis_). */
8453 /* Use BAD_CONVERSION_RANK because we already checked for a badness
8454 mismatch. If both ICS are bad, we try to make a decision based on
8455 what would have happened if they'd been good. This is not an
8456 extension, we'll still give an error when we build up the call; this
8457 just helps us give a more helpful error message. */
8458 rank1 = BAD_CONVERSION_RANK (ics1);
8459 rank2 = BAD_CONVERSION_RANK (ics2);
8463 else if (rank1 < rank2)
8466 if (ics1->ellipsis_p)
8467 /* Both conversions are ellipsis conversions. */
8470 /* User-defined conversion sequence U1 is a better conversion sequence
8471 than another user-defined conversion sequence U2 if they contain the
8472 same user-defined conversion operator or constructor and if the sec-
8473 ond standard conversion sequence of U1 is better than the second
8474 standard conversion sequence of U2. */
8476 /* Handle list-conversion with the same code even though it isn't always
8477 ranked as a user-defined conversion and it doesn't have a second
8478 standard conversion sequence; it will still have the desired effect.
8479 Specifically, we need to do the reference binding comparison at the
8480 end of this function. */
8482 if (ics1->user_conv_p || ics1->kind == ck_list || ics1->kind == ck_aggr)
8487 for (t1 = ics1; t1->kind != ck_user; t1 = next_conversion (t1))
8488 if (t1->kind == ck_ambig || t1->kind == ck_aggr
8489 || t1->kind == ck_list)
8491 for (t2 = ics2; t2->kind != ck_user; t2 = next_conversion (t2))
8492 if (t2->kind == ck_ambig || t2->kind == ck_aggr
8493 || t2->kind == ck_list)
8496 if (t1->kind != t2->kind)
8498 else if (t1->kind == ck_user)
8500 if (t1->cand->fn != t2->cand->fn)
8505 /* For ambiguous or aggregate conversions, use the target type as
8506 a proxy for the conversion function. */
8507 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
8511 /* We can just fall through here, after setting up
8512 FROM_TYPE1 and FROM_TYPE2. */
8513 from_type1 = t1->type;
8514 from_type2 = t2->type;
8521 /* We're dealing with two standard conversion sequences.
8525 Standard conversion sequence S1 is a better conversion
8526 sequence than standard conversion sequence S2 if
8528 --S1 is a proper subsequence of S2 (comparing the conversion
8529 sequences in the canonical form defined by _over.ics.scs_,
8530 excluding any Lvalue Transformation; the identity
8531 conversion sequence is considered to be a subsequence of
8532 any non-identity conversion sequence */
8535 while (t1->kind != ck_identity)
8536 t1 = next_conversion (t1);
8537 from_type1 = t1->type;
8540 while (t2->kind != ck_identity)
8541 t2 = next_conversion (t2);
8542 from_type2 = t2->type;
8545 /* One sequence can only be a subsequence of the other if they start with
8546 the same type. They can start with different types when comparing the
8547 second standard conversion sequence in two user-defined conversion
8549 if (same_type_p (from_type1, from_type2))
8551 if (is_subseq (ics1, ics2))
8553 if (is_subseq (ics2, ics1))
8561 --the rank of S1 is better than the rank of S2 (by the rules
8564 Standard conversion sequences are ordered by their ranks: an Exact
8565 Match is a better conversion than a Promotion, which is a better
8566 conversion than a Conversion.
8568 Two conversion sequences with the same rank are indistinguishable
8569 unless one of the following rules applies:
8571 --A conversion that does not a convert a pointer, pointer to member,
8572 or std::nullptr_t to bool is better than one that does.
8574 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
8575 so that we do not have to check it explicitly. */
8576 if (ics1->rank < ics2->rank)
8578 else if (ics2->rank < ics1->rank)
8581 to_type1 = ics1->type;
8582 to_type2 = ics2->type;
8584 /* A conversion from scalar arithmetic type to complex is worse than a
8585 conversion between scalar arithmetic types. */
8586 if (same_type_p (from_type1, from_type2)
8587 && ARITHMETIC_TYPE_P (from_type1)
8588 && ARITHMETIC_TYPE_P (to_type1)
8589 && ARITHMETIC_TYPE_P (to_type2)
8590 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
8591 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
8593 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
8599 if (TYPE_PTR_P (from_type1)
8600 && TYPE_PTR_P (from_type2)
8601 && TYPE_PTR_P (to_type1)
8602 && TYPE_PTR_P (to_type2))
8604 deref_from_type1 = TREE_TYPE (from_type1);
8605 deref_from_type2 = TREE_TYPE (from_type2);
8606 deref_to_type1 = TREE_TYPE (to_type1);
8607 deref_to_type2 = TREE_TYPE (to_type2);
8609 /* The rules for pointers to members A::* are just like the rules
8610 for pointers A*, except opposite: if B is derived from A then
8611 A::* converts to B::*, not vice versa. For that reason, we
8612 switch the from_ and to_ variables here. */
8613 else if ((TYPE_PTRDATAMEM_P (from_type1) && TYPE_PTRDATAMEM_P (from_type2)
8614 && TYPE_PTRDATAMEM_P (to_type1) && TYPE_PTRDATAMEM_P (to_type2))
8615 || (TYPE_PTRMEMFUNC_P (from_type1)
8616 && TYPE_PTRMEMFUNC_P (from_type2)
8617 && TYPE_PTRMEMFUNC_P (to_type1)
8618 && TYPE_PTRMEMFUNC_P (to_type2)))
8620 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
8621 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
8622 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
8623 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
8626 if (deref_from_type1 != NULL_TREE
8627 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
8628 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
8630 /* This was one of the pointer or pointer-like conversions.
8634 --If class B is derived directly or indirectly from class A,
8635 conversion of B* to A* is better than conversion of B* to
8636 void*, and conversion of A* to void* is better than
8637 conversion of B* to void*. */
8638 if (VOID_TYPE_P (deref_to_type1)
8639 && VOID_TYPE_P (deref_to_type2))
8641 if (is_properly_derived_from (deref_from_type1,
8644 else if (is_properly_derived_from (deref_from_type2,
8648 else if (VOID_TYPE_P (deref_to_type1)
8649 || VOID_TYPE_P (deref_to_type2))
8651 if (same_type_p (deref_from_type1, deref_from_type2))
8653 if (VOID_TYPE_P (deref_to_type2))
8655 if (is_properly_derived_from (deref_from_type1,
8659 /* We know that DEREF_TO_TYPE1 is `void' here. */
8660 else if (is_properly_derived_from (deref_from_type1,
8665 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
8666 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
8670 --If class B is derived directly or indirectly from class A
8671 and class C is derived directly or indirectly from B,
8673 --conversion of C* to B* is better than conversion of C* to
8676 --conversion of B* to A* is better than conversion of C* to
8678 if (same_type_p (deref_from_type1, deref_from_type2))
8680 if (is_properly_derived_from (deref_to_type1,
8683 else if (is_properly_derived_from (deref_to_type2,
8687 else if (same_type_p (deref_to_type1, deref_to_type2))
8689 if (is_properly_derived_from (deref_from_type2,
8692 else if (is_properly_derived_from (deref_from_type1,
8698 else if (CLASS_TYPE_P (non_reference (from_type1))
8699 && same_type_p (from_type1, from_type2))
8701 tree from = non_reference (from_type1);
8705 --binding of an expression of type C to a reference of type
8706 B& is better than binding an expression of type C to a
8707 reference of type A&
8709 --conversion of C to B is better than conversion of C to A, */
8710 if (is_properly_derived_from (from, to_type1)
8711 && is_properly_derived_from (from, to_type2))
8713 if (is_properly_derived_from (to_type1, to_type2))
8715 else if (is_properly_derived_from (to_type2, to_type1))
8719 else if (CLASS_TYPE_P (non_reference (to_type1))
8720 && same_type_p (to_type1, to_type2))
8722 tree to = non_reference (to_type1);
8726 --binding of an expression of type B to a reference of type
8727 A& is better than binding an expression of type C to a
8728 reference of type A&,
8730 --conversion of B to A is better than conversion of C to A */
8731 if (is_properly_derived_from (from_type1, to)
8732 && is_properly_derived_from (from_type2, to))
8734 if (is_properly_derived_from (from_type2, from_type1))
8736 else if (is_properly_derived_from (from_type1, from_type2))
8743 --S1 and S2 differ only in their qualification conversion and yield
8744 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
8745 qualification signature of type T1 is a proper subset of the cv-
8746 qualification signature of type T2 */
8747 if (ics1->kind == ck_qual
8748 && ics2->kind == ck_qual
8749 && same_type_p (from_type1, from_type2))
8751 int result = comp_cv_qual_signature (to_type1, to_type2);
8758 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
8759 to an implicit object parameter of a non-static member function
8760 declared without a ref-qualifier, and either S1 binds an lvalue
8761 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
8762 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
8763 draft standard, 13.3.3.2)
8765 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
8766 types to which the references refer are the same type except for
8767 top-level cv-qualifiers, and the type to which the reference
8768 initialized by S2 refers is more cv-qualified than the type to
8769 which the reference initialized by S1 refers.
8771 DR 1328 [over.match.best]: the context is an initialization by
8772 conversion function for direct reference binding (13.3.1.6) of a
8773 reference to function type, the return type of F1 is the same kind of
8774 reference (i.e. lvalue or rvalue) as the reference being initialized,
8775 and the return type of F2 is not. */
8777 if (ref_conv1 && ref_conv2)
8779 if (!ref_conv1->this_p && !ref_conv2->this_p
8780 && (ref_conv1->rvaluedness_matches_p
8781 != ref_conv2->rvaluedness_matches_p)
8782 && (same_type_p (ref_conv1->type, ref_conv2->type)
8783 || (TYPE_REF_IS_RVALUE (ref_conv1->type)
8784 != TYPE_REF_IS_RVALUE (ref_conv2->type))))
8786 if (ref_conv1->bad_p
8787 && !same_type_p (TREE_TYPE (ref_conv1->type),
8788 TREE_TYPE (ref_conv2->type)))
8789 /* Don't prefer a bad conversion that drops cv-quals to a bad
8790 conversion with the wrong rvalueness. */
8792 return (ref_conv1->rvaluedness_matches_p
8793 - ref_conv2->rvaluedness_matches_p);
8796 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
8798 int q1 = cp_type_quals (TREE_TYPE (ref_conv1->type));
8799 int q2 = cp_type_quals (TREE_TYPE (ref_conv2->type));
8800 if (ref_conv1->bad_p)
8802 /* Prefer the one that drops fewer cv-quals. */
8803 tree ftype = next_conversion (ref_conv1)->type;
8804 int fquals = cp_type_quals (ftype);
8808 return comp_cv_qualification (q2, q1);
8812 /* Neither conversion sequence is better than the other. */
8816 /* The source type for this standard conversion sequence. */
8819 source_type (conversion *t)
8821 for (;; t = next_conversion (t))
8823 if (t->kind == ck_user
8824 || t->kind == ck_ambig
8825 || t->kind == ck_identity)
8831 /* Note a warning about preferring WINNER to LOSER. We do this by storing
8832 a pointer to LOSER and re-running joust to produce the warning if WINNER
8833 is actually used. */
8836 add_warning (struct z_candidate *winner, struct z_candidate *loser)
8838 candidate_warning *cw = (candidate_warning *)
8839 conversion_obstack_alloc (sizeof (candidate_warning));
8841 cw->next = winner->warnings;
8842 winner->warnings = cw;
8845 /* Compare two candidates for overloading as described in
8846 [over.match.best]. Return values:
8848 1: cand1 is better than cand2
8849 -1: cand2 is better than cand1
8850 0: cand1 and cand2 are indistinguishable */
8853 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn,
8854 tsubst_flags_t complain)
8857 int off1 = 0, off2 = 0;
8861 /* Candidates that involve bad conversions are always worse than those
8863 if (cand1->viable > cand2->viable)
8865 if (cand1->viable < cand2->viable)
8868 /* If we have two pseudo-candidates for conversions to the same type,
8869 or two candidates for the same function, arbitrarily pick one. */
8870 if (cand1->fn == cand2->fn
8871 && (IS_TYPE_OR_DECL_P (cand1->fn)))
8874 /* Prefer a non-deleted function over an implicitly deleted move
8875 constructor or assignment operator. This differs slightly from the
8876 wording for issue 1402 (which says the move op is ignored by overload
8877 resolution), but this way produces better error messages. */
8878 if (TREE_CODE (cand1->fn) == FUNCTION_DECL
8879 && TREE_CODE (cand2->fn) == FUNCTION_DECL
8880 && DECL_DELETED_FN (cand1->fn) != DECL_DELETED_FN (cand2->fn))
8882 if (DECL_DELETED_FN (cand1->fn) && DECL_DEFAULTED_FN (cand1->fn)
8883 && move_fn_p (cand1->fn))
8885 if (DECL_DELETED_FN (cand2->fn) && DECL_DEFAULTED_FN (cand2->fn)
8886 && move_fn_p (cand2->fn))
8890 /* a viable function F1
8891 is defined to be a better function than another viable function F2 if
8892 for all arguments i, ICSi(F1) is not a worse conversion sequence than
8893 ICSi(F2), and then */
8895 /* for some argument j, ICSj(F1) is a better conversion sequence than
8898 /* For comparing static and non-static member functions, we ignore
8899 the implicit object parameter of the non-static function. The
8900 standard says to pretend that the static function has an object
8901 parm, but that won't work with operator overloading. */
8902 len = cand1->num_convs;
8903 if (len != cand2->num_convs)
8905 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
8906 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
8908 if (DECL_CONSTRUCTOR_P (cand1->fn)
8909 && is_list_ctor (cand1->fn) != is_list_ctor (cand2->fn))
8910 /* We're comparing a near-match list constructor and a near-match
8911 non-list constructor. Just treat them as unordered. */
8914 gcc_assert (static_1 != static_2);
8925 for (i = 0; i < len; ++i)
8927 conversion *t1 = cand1->convs[i + off1];
8928 conversion *t2 = cand2->convs[i + off2];
8929 int comp = compare_ics (t1, t2);
8933 if ((complain & tf_warning)
8935 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
8936 == cr_std + cr_promotion)
8937 && t1->kind == ck_std
8938 && t2->kind == ck_std
8939 && TREE_CODE (t1->type) == INTEGER_TYPE
8940 && TREE_CODE (t2->type) == INTEGER_TYPE
8941 && (TYPE_PRECISION (t1->type)
8942 == TYPE_PRECISION (t2->type))
8943 && (TYPE_UNSIGNED (next_conversion (t1)->type)
8944 || (TREE_CODE (next_conversion (t1)->type)
8947 tree type = next_conversion (t1)->type;
8949 struct z_candidate *w, *l;
8951 type1 = t1->type, type2 = t2->type,
8952 w = cand1, l = cand2;
8954 type1 = t2->type, type2 = t1->type,
8955 w = cand2, l = cand1;
8959 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
8960 type, type1, type2);
8961 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
8967 if (winner && comp != winner)
8976 /* warn about confusing overload resolution for user-defined conversions,
8977 either between a constructor and a conversion op, or between two
8979 if ((complain & tf_warning)
8980 && winner && warn_conversion && cand1->second_conv
8981 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
8982 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
8984 struct z_candidate *w, *l;
8985 bool give_warning = false;
8988 w = cand1, l = cand2;
8990 w = cand2, l = cand1;
8992 /* We don't want to complain about `X::operator T1 ()'
8993 beating `X::operator T2 () const', when T2 is a no less
8994 cv-qualified version of T1. */
8995 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
8996 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
8998 tree t = TREE_TYPE (TREE_TYPE (l->fn));
8999 tree f = TREE_TYPE (TREE_TYPE (w->fn));
9001 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
9006 if (!comp_ptr_ttypes (t, f))
9007 give_warning = true;
9010 give_warning = true;
9016 tree source = source_type (w->convs[0]);
9017 if (! DECL_CONSTRUCTOR_P (w->fn))
9018 source = TREE_TYPE (source);
9019 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
9020 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
9021 source, w->second_conv->type))
9023 inform (input_location, " because conversion sequence for the argument is better");
9033 /* DR 495 moved this tiebreaker above the template ones. */
9035 the context is an initialization by user-defined conversion (see
9036 _dcl.init_ and _over.match.user_) and the standard conversion
9037 sequence from the return type of F1 to the destination type (i.e.,
9038 the type of the entity being initialized) is a better conversion
9039 sequence than the standard conversion sequence from the return type
9040 of F2 to the destination type. */
9042 if (cand1->second_conv)
9044 winner = compare_ics (cand1->second_conv, cand2->second_conv);
9050 F1 is a non-template function and F2 is a template function
9053 if (!cand1->template_decl && cand2->template_decl)
9055 else if (cand1->template_decl && !cand2->template_decl)
9059 F1 and F2 are template functions and the function template for F1 is
9060 more specialized than the template for F2 according to the partial
9063 if (cand1->template_decl && cand2->template_decl)
9065 winner = more_specialized_fn
9066 (TI_TEMPLATE (cand1->template_decl),
9067 TI_TEMPLATE (cand2->template_decl),
9068 /* [temp.func.order]: The presence of unused ellipsis and default
9069 arguments has no effect on the partial ordering of function
9070 templates. add_function_candidate() will not have
9071 counted the "this" argument for constructors. */
9072 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
9077 /* Check whether we can discard a builtin candidate, either because we
9078 have two identical ones or matching builtin and non-builtin candidates.
9080 (Pedantically in the latter case the builtin which matched the user
9081 function should not be added to the overload set, but we spot it here.
9084 ... the builtin candidates include ...
9085 - do not have the same parameter type list as any non-template
9086 non-member candidate. */
9088 if (identifier_p (cand1->fn) || identifier_p (cand2->fn))
9090 for (i = 0; i < len; ++i)
9091 if (!same_type_p (cand1->convs[i]->type,
9092 cand2->convs[i]->type))
9094 if (i == cand1->num_convs)
9096 if (cand1->fn == cand2->fn)
9097 /* Two built-in candidates; arbitrarily pick one. */
9099 else if (identifier_p (cand1->fn))
9100 /* cand1 is built-in; prefer cand2. */
9103 /* cand2 is built-in; prefer cand1. */
9108 /* For candidates of a multi-versioned function, make the version with
9109 the highest priority win. This version will be checked for dispatching
9110 first. If this version can be inlined into the caller, the front-end
9111 will simply make a direct call to this function. */
9113 if (TREE_CODE (cand1->fn) == FUNCTION_DECL
9114 && DECL_FUNCTION_VERSIONED (cand1->fn)
9115 && TREE_CODE (cand2->fn) == FUNCTION_DECL
9116 && DECL_FUNCTION_VERSIONED (cand2->fn))
9118 tree f1 = TREE_TYPE (cand1->fn);
9119 tree f2 = TREE_TYPE (cand2->fn);
9120 tree p1 = TYPE_ARG_TYPES (f1);
9121 tree p2 = TYPE_ARG_TYPES (f2);
9123 /* Check if cand1->fn and cand2->fn are versions of the same function. It
9124 is possible that cand1->fn and cand2->fn are function versions but of
9125 different functions. Check types to see if they are versions of the same
9127 if (compparms (p1, p2)
9128 && same_type_p (TREE_TYPE (f1), TREE_TYPE (f2)))
9130 /* Always make the version with the higher priority, more
9131 specialized, win. */
9132 gcc_assert (targetm.compare_version_priority);
9133 if (targetm.compare_version_priority (cand1->fn, cand2->fn) >= 0)
9140 /* If the two function declarations represent the same function (this can
9141 happen with declarations in multiple scopes and arg-dependent lookup),
9142 arbitrarily choose one. But first make sure the default args we're
9144 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
9145 && equal_functions (cand1->fn, cand2->fn))
9147 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
9148 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
9150 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
9152 for (i = 0; i < len; ++i)
9154 /* Don't crash if the fn is variadic. */
9157 parms1 = TREE_CHAIN (parms1);
9158 parms2 = TREE_CHAIN (parms2);
9162 parms1 = TREE_CHAIN (parms1);
9164 parms2 = TREE_CHAIN (parms2);
9168 if (!cp_tree_equal (TREE_PURPOSE (parms1),
9169 TREE_PURPOSE (parms2)))
9173 if (complain & tf_error)
9175 if (permerror (input_location,
9176 "default argument mismatch in "
9177 "overload resolution"))
9179 inform (input_location,
9180 " candidate 1: %q+#F", cand1->fn);
9181 inform (input_location,
9182 " candidate 2: %q+#F", cand2->fn);
9189 add_warning (cand1, cand2);
9192 parms1 = TREE_CHAIN (parms1);
9193 parms2 = TREE_CHAIN (parms2);
9201 /* Extension: If the worst conversion for one candidate is worse than the
9202 worst conversion for the other, take the first. */
9203 if (!pedantic && (complain & tf_warning_or_error))
9205 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
9206 struct z_candidate *w = 0, *l = 0;
9208 for (i = 0; i < len; ++i)
9210 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
9211 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
9212 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
9213 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
9216 winner = 1, w = cand1, l = cand2;
9218 winner = -1, w = cand2, l = cand1;
9221 /* Don't choose a deleted function over ambiguity. */
9222 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
9226 pedwarn (input_location, 0,
9227 "ISO C++ says that these are ambiguous, even "
9228 "though the worst conversion for the first is better than "
9229 "the worst conversion for the second:");
9230 print_z_candidate (input_location, _("candidate 1:"), w);
9231 print_z_candidate (input_location, _("candidate 2:"), l);
9239 gcc_assert (!winner);
9243 /* Given a list of candidates for overloading, find the best one, if any.
9244 This algorithm has a worst case of O(2n) (winner is last), and a best
9245 case of O(n/2) (totally ambiguous); much better than a sorting
9248 static struct z_candidate *
9249 tourney (struct z_candidate *candidates, tsubst_flags_t complain)
9251 struct z_candidate *champ = candidates, *challenger;
9253 int champ_compared_to_predecessor = 0;
9255 /* Walk through the list once, comparing each current champ to the next
9256 candidate, knocking out a candidate or two with each comparison. */
9258 for (challenger = champ->next; challenger; )
9260 fate = joust (champ, challenger, 0, complain);
9262 challenger = challenger->next;
9267 champ = challenger->next;
9270 champ_compared_to_predecessor = 0;
9275 champ_compared_to_predecessor = 1;
9278 challenger = champ->next;
9282 /* Make sure the champ is better than all the candidates it hasn't yet
9283 been compared to. */
9285 for (challenger = candidates;
9287 && !(champ_compared_to_predecessor && challenger->next == champ);
9288 challenger = challenger->next)
9290 fate = joust (champ, challenger, 0, complain);
9298 /* Returns nonzero if things of type FROM can be converted to TO. */
9301 can_convert (tree to, tree from, tsubst_flags_t complain)
9303 tree arg = NULL_TREE;
9304 /* implicit_conversion only considers user-defined conversions
9305 if it has an expression for the call argument list. */
9306 if (CLASS_TYPE_P (from) || CLASS_TYPE_P (to))
9307 arg = build1 (CAST_EXPR, from, NULL_TREE);
9308 return can_convert_arg (to, from, arg, LOOKUP_IMPLICIT, complain);
9311 /* Returns nonzero if things of type FROM can be converted to TO with a
9312 standard conversion. */
9315 can_convert_standard (tree to, tree from, tsubst_flags_t complain)
9317 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT, complain);
9320 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
9323 can_convert_arg (tree to, tree from, tree arg, int flags,
9324 tsubst_flags_t complain)
9330 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9331 p = conversion_obstack_alloc (0);
9332 /* We want to discard any access checks done for this test,
9333 as we might not be in the appropriate access context and
9334 we'll do the check again when we actually perform the
9336 push_deferring_access_checks (dk_deferred);
9338 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
9340 ok_p = (t && !t->bad_p);
9342 /* Discard the access checks now. */
9343 pop_deferring_access_checks ();
9344 /* Free all the conversions we allocated. */
9345 obstack_free (&conversion_obstack, p);
9350 /* Like can_convert_arg, but allows dubious conversions as well. */
9353 can_convert_arg_bad (tree to, tree from, tree arg, int flags,
9354 tsubst_flags_t complain)
9359 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9360 p = conversion_obstack_alloc (0);
9361 /* Try to perform the conversion. */
9362 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
9364 /* Free all the conversions we allocated. */
9365 obstack_free (&conversion_obstack, p);
9370 /* Convert EXPR to TYPE. Return the converted expression.
9372 Note that we allow bad conversions here because by the time we get to
9373 this point we are committed to doing the conversion. If we end up
9374 doing a bad conversion, convert_like will complain. */
9377 perform_implicit_conversion_flags (tree type, tree expr,
9378 tsubst_flags_t complain, int flags)
9382 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
9384 if (error_operand_p (expr))
9385 return error_mark_node;
9387 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9388 p = conversion_obstack_alloc (0);
9390 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
9396 if (complain & tf_error)
9398 /* If expr has unknown type, then it is an overloaded function.
9399 Call instantiate_type to get good error messages. */
9400 if (TREE_TYPE (expr) == unknown_type_node)
9401 instantiate_type (type, expr, complain);
9402 else if (invalid_nonstatic_memfn_p (expr, complain))
9403 /* We gave an error. */;
9405 error_at (loc, "could not convert %qE from %qT to %qT", expr,
9406 TREE_TYPE (expr), type);
9408 expr = error_mark_node;
9410 else if (processing_template_decl && conv->kind != ck_identity)
9412 /* In a template, we are only concerned about determining the
9413 type of non-dependent expressions, so we do not have to
9414 perform the actual conversion. But for initializers, we
9415 need to be able to perform it at instantiation
9416 (or instantiate_non_dependent_expr) time. */
9417 expr = build1 (IMPLICIT_CONV_EXPR, type, expr);
9418 if (!(flags & LOOKUP_ONLYCONVERTING))
9419 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr) = true;
9422 expr = convert_like (conv, expr, complain);
9424 /* Free all the conversions we allocated. */
9425 obstack_free (&conversion_obstack, p);
9431 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
9433 return perform_implicit_conversion_flags (type, expr, complain,
9437 /* Convert EXPR to TYPE (as a direct-initialization) if that is
9438 permitted. If the conversion is valid, the converted expression is
9439 returned. Otherwise, NULL_TREE is returned, except in the case
9440 that TYPE is a class type; in that case, an error is issued. If
9441 C_CAST_P is true, then this direct-initialization is taking
9442 place as part of a static_cast being attempted as part of a C-style
9446 perform_direct_initialization_if_possible (tree type,
9449 tsubst_flags_t complain)
9454 if (type == error_mark_node || error_operand_p (expr))
9455 return error_mark_node;
9458 If the destination type is a (possibly cv-qualified) class type:
9460 -- If the initialization is direct-initialization ...,
9461 constructors are considered. ... If no constructor applies, or
9462 the overload resolution is ambiguous, the initialization is
9464 if (CLASS_TYPE_P (type))
9466 vec<tree, va_gc> *args = make_tree_vector_single (expr);
9467 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
9468 &args, type, LOOKUP_NORMAL, complain);
9469 release_tree_vector (args);
9470 return build_cplus_new (type, expr, complain);
9473 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9474 p = conversion_obstack_alloc (0);
9476 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
9478 LOOKUP_NORMAL, complain);
9479 if (!conv || conv->bad_p)
9482 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
9483 /*issue_conversion_warnings=*/false,
9487 /* Free all the conversions we allocated. */
9488 obstack_free (&conversion_obstack, p);
9493 /* When initializing a reference that lasts longer than a full-expression,
9494 this special rule applies:
9498 The temporary to which the reference is bound or the temporary
9499 that is the complete object to which the reference is bound
9500 persists for the lifetime of the reference.
9502 The temporaries created during the evaluation of the expression
9503 initializing the reference, except the temporary to which the
9504 reference is bound, are destroyed at the end of the
9505 full-expression in which they are created.
9507 In that case, we store the converted expression into a new
9508 VAR_DECL in a new scope.
9510 However, we want to be careful not to create temporaries when
9511 they are not required. For example, given:
9514 struct D : public B {};
9518 there is no need to copy the return value from "f"; we can just
9519 extend its lifetime. Similarly, given:
9522 struct T { operator S(); };
9526 we can extend the lifetime of the return value of the conversion
9529 The next several functions are involved in this lifetime extension. */
9531 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
9532 reference is being bound to a temporary. Create and return a new
9533 VAR_DECL with the indicated TYPE; this variable will store the value to
9534 which the reference is bound. */
9537 make_temporary_var_for_ref_to_temp (tree decl, tree type)
9541 /* Create the variable. */
9542 var = create_temporary_var (type);
9544 /* Register the variable. */
9546 && (TREE_STATIC (decl) || DECL_THREAD_LOCAL_P (decl)))
9548 /* Namespace-scope or local static; give it a mangled name. */
9549 /* FIXME share comdat with decl? */
9552 TREE_STATIC (var) = TREE_STATIC (decl);
9553 set_decl_tls_model (var, DECL_TLS_MODEL (decl));
9554 name = mangle_ref_init_variable (decl);
9555 DECL_NAME (var) = name;
9556 SET_DECL_ASSEMBLER_NAME (var, name);
9557 var = pushdecl_top_level (var);
9560 /* Create a new cleanup level if necessary. */
9561 maybe_push_cleanup_level (type);
9566 /* EXPR is the initializer for a variable DECL of reference or
9567 std::initializer_list type. Create, push and return a new VAR_DECL
9568 for the initializer so that it will live as long as DECL. Any
9569 cleanup for the new variable is returned through CLEANUP, and the
9570 code to initialize the new variable is returned through INITP. */
9573 set_up_extended_ref_temp (tree decl, tree expr, vec<tree, va_gc> **cleanups,
9580 /* Create the temporary variable. */
9581 type = TREE_TYPE (expr);
9582 var = make_temporary_var_for_ref_to_temp (decl, type);
9583 layout_decl (var, 0);
9584 /* If the rvalue is the result of a function call it will be
9585 a TARGET_EXPR. If it is some other construct (such as a
9586 member access expression where the underlying object is
9587 itself the result of a function call), turn it into a
9588 TARGET_EXPR here. It is important that EXPR be a
9589 TARGET_EXPR below since otherwise the INIT_EXPR will
9590 attempt to make a bitwise copy of EXPR to initialize
9592 if (TREE_CODE (expr) != TARGET_EXPR)
9593 expr = get_target_expr (expr);
9595 if (TREE_CODE (decl) == FIELD_DECL
9596 && extra_warnings && !TREE_NO_WARNING (decl))
9598 warning (OPT_Wextra, "a temporary bound to %qD only persists "
9599 "until the constructor exits", decl);
9600 TREE_NO_WARNING (decl) = true;
9603 /* Recursively extend temps in this initializer. */
9604 TARGET_EXPR_INITIAL (expr)
9605 = extend_ref_init_temps (decl, TARGET_EXPR_INITIAL (expr), cleanups);
9607 /* Any reference temp has a non-trivial initializer. */
9608 DECL_NONTRIVIALLY_INITIALIZED_P (var) = true;
9610 /* If the initializer is constant, put it in DECL_INITIAL so we get
9611 static initialization and use in constant expressions. */
9612 init = maybe_constant_init (expr);
9613 if (TREE_CONSTANT (init))
9615 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
9617 /* 5.19 says that a constant expression can include an
9618 lvalue-rvalue conversion applied to "a glvalue of literal type
9619 that refers to a non-volatile temporary object initialized
9620 with a constant expression". Rather than try to communicate
9621 that this VAR_DECL is a temporary, just mark it constexpr.
9623 Currently this is only useful for initializer_list temporaries,
9624 since reference vars can't appear in constant expressions. */
9625 DECL_DECLARED_CONSTEXPR_P (var) = true;
9626 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
9627 TREE_CONSTANT (var) = true;
9629 DECL_INITIAL (var) = init;
9633 /* Create the INIT_EXPR that will initialize the temporary
9635 init = split_nonconstant_init (var, expr);
9636 if (at_function_scope_p ())
9638 add_decl_expr (var);
9640 if (TREE_STATIC (var))
9641 init = add_stmt_to_compound (init, register_dtor_fn (var));
9644 tree cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error);
9646 vec_safe_push (*cleanups, cleanup);
9649 /* We must be careful to destroy the temporary only
9650 after its initialization has taken place. If the
9651 initialization throws an exception, then the
9652 destructor should not be run. We cannot simply
9653 transform INIT into something like:
9655 (INIT, ({ CLEANUP_STMT; }))
9657 because emit_local_var always treats the
9658 initializer as a full-expression. Thus, the
9659 destructor would run too early; it would run at the
9660 end of initializing the reference variable, rather
9661 than at the end of the block enclosing the
9664 The solution is to pass back a cleanup expression
9665 which the caller is responsible for attaching to
9666 the statement tree. */
9670 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
9671 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
9673 if (DECL_THREAD_LOCAL_P (var))
9674 tls_aggregates = tree_cons (NULL_TREE, var,
9677 static_aggregates = tree_cons (NULL_TREE, var,
9681 /* Check whether the dtor is callable. */
9682 cxx_maybe_build_cleanup (var, tf_warning_or_error);
9684 /* Avoid -Wunused-variable warning (c++/38958). */
9685 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
9686 && TREE_CODE (decl) == VAR_DECL)
9687 TREE_USED (decl) = DECL_READ_P (decl) = true;
9693 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
9694 initializing a variable of that TYPE. */
9697 initialize_reference (tree type, tree expr,
9698 int flags, tsubst_flags_t complain)
9702 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
9704 if (type == error_mark_node || error_operand_p (expr))
9705 return error_mark_node;
9707 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9708 p = conversion_obstack_alloc (0);
9710 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
9712 if (!conv || conv->bad_p)
9714 if (complain & tf_error)
9717 convert_like (conv, expr, complain);
9718 else if (!CP_TYPE_CONST_P (TREE_TYPE (type))
9719 && !TYPE_REF_IS_RVALUE (type)
9720 && !real_lvalue_p (expr))
9721 error_at (loc, "invalid initialization of non-const reference of "
9722 "type %qT from an rvalue of type %qT",
9723 type, TREE_TYPE (expr));
9725 error_at (loc, "invalid initialization of reference of type "
9726 "%qT from expression of type %qT", type,
9729 return error_mark_node;
9732 if (conv->kind == ck_ref_bind)
9733 /* Perform the conversion. */
9734 expr = convert_like (conv, expr, complain);
9735 else if (conv->kind == ck_ambig)
9736 /* We gave an error in build_user_type_conversion_1. */
9737 expr = error_mark_node;
9741 /* Free all the conversions we allocated. */
9742 obstack_free (&conversion_obstack, p);
9747 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
9748 which is bound either to a reference or a std::initializer_list. */
9751 extend_ref_init_temps_1 (tree decl, tree init, vec<tree, va_gc> **cleanups)
9756 if (TREE_CODE (sub) == COMPOUND_EXPR)
9758 TREE_OPERAND (sub, 1)
9759 = extend_ref_init_temps_1 (decl, TREE_OPERAND (sub, 1), cleanups);
9762 if (TREE_CODE (sub) != ADDR_EXPR)
9764 /* Deal with binding to a subobject. */
9765 for (p = &TREE_OPERAND (sub, 0); TREE_CODE (*p) == COMPONENT_REF; )
9766 p = &TREE_OPERAND (*p, 0);
9767 if (TREE_CODE (*p) == TARGET_EXPR)
9769 tree subinit = NULL_TREE;
9770 *p = set_up_extended_ref_temp (decl, *p, cleanups, &subinit);
9771 recompute_tree_invariant_for_addr_expr (sub);
9773 init = fold_convert (TREE_TYPE (init), sub);
9775 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), subinit, init);
9780 /* INIT is part of the initializer for DECL. If there are any
9781 reference or initializer lists being initialized, extend their
9782 lifetime to match that of DECL. */
9785 extend_ref_init_temps (tree decl, tree init, vec<tree, va_gc> **cleanups)
9787 tree type = TREE_TYPE (init);
9788 if (processing_template_decl)
9790 if (TREE_CODE (type) == REFERENCE_TYPE)
9791 init = extend_ref_init_temps_1 (decl, init, cleanups);
9792 else if (is_std_init_list (type))
9794 /* The temporary array underlying a std::initializer_list
9795 is handled like a reference temporary. */
9797 if (TREE_CODE (ctor) == TARGET_EXPR)
9798 ctor = TARGET_EXPR_INITIAL (ctor);
9799 if (TREE_CODE (ctor) == CONSTRUCTOR)
9801 tree array = CONSTRUCTOR_ELT (ctor, 0)->value;
9802 array = extend_ref_init_temps_1 (decl, array, cleanups);
9803 CONSTRUCTOR_ELT (ctor, 0)->value = array;
9806 else if (TREE_CODE (init) == CONSTRUCTOR)
9810 vec<constructor_elt, va_gc> *elts = CONSTRUCTOR_ELTS (init);
9811 FOR_EACH_VEC_SAFE_ELT (elts, i, p)
9812 p->value = extend_ref_init_temps (decl, p->value, cleanups);
9818 /* Returns true iff an initializer for TYPE could contain temporaries that
9819 need to be extended because they are bound to references or
9820 std::initializer_list. */
9823 type_has_extended_temps (tree type)
9825 type = strip_array_types (type);
9826 if (TREE_CODE (type) == REFERENCE_TYPE)
9828 if (CLASS_TYPE_P (type))
9830 if (is_std_init_list (type))
9832 for (tree f = next_initializable_field (TYPE_FIELDS (type));
9833 f; f = next_initializable_field (DECL_CHAIN (f)))
9834 if (type_has_extended_temps (TREE_TYPE (f)))
9840 /* Returns true iff TYPE is some variant of std::initializer_list. */
9843 is_std_init_list (tree type)
9845 /* Look through typedefs. */
9848 if (cxx_dialect == cxx98)
9850 type = TYPE_MAIN_VARIANT (type);
9851 return (CLASS_TYPE_P (type)
9852 && CP_TYPE_CONTEXT (type) == std_node
9853 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
9856 /* Returns true iff DECL is a list constructor: i.e. a constructor which
9857 will accept an argument list of a single std::initializer_list<T>. */
9860 is_list_ctor (tree decl)
9862 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
9865 if (!args || args == void_list_node)
9868 arg = non_reference (TREE_VALUE (args));
9869 if (!is_std_init_list (arg))
9872 args = TREE_CHAIN (args);
9874 if (args && args != void_list_node && !TREE_PURPOSE (args))
9875 /* There are more non-defaulted parms. */
9881 #include "gt-cp-call.h"