1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
5 Free Software Foundation, Inc.
6 Contributed by Michael Tiemann (tiemann@cygnus.com) and
7 modified by Brendan Kehoe (brendan@cygnus.com).
9 This file is part of GCC.
11 GCC is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 3, or (at your option)
16 GCC is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
26 /* High-level class interface. */
30 #include "coretypes.h"
37 #include "diagnostic-core.h"
41 #include "langhooks.h"
42 #include "c-family/c-objc.h"
45 /* The various kinds of conversion. */
47 typedef enum conversion_kind {
63 /* The rank of the conversion. Order of the enumerals matters; better
64 conversions should come earlier in the list. */
66 typedef enum conversion_rank {
77 /* An implicit conversion sequence, in the sense of [over.best.ics].
78 The first conversion to be performed is at the end of the chain.
79 That conversion is always a cr_identity conversion. */
81 typedef struct conversion conversion;
83 /* The kind of conversion represented by this step. */
85 /* The rank of this conversion. */
87 BOOL_BITFIELD user_conv_p : 1;
88 BOOL_BITFIELD ellipsis_p : 1;
89 BOOL_BITFIELD this_p : 1;
90 /* True if this conversion would be permitted with a bending of
91 language standards, e.g. disregarding pointer qualifiers or
92 converting integers to pointers. */
93 BOOL_BITFIELD bad_p : 1;
94 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
95 temporary should be created to hold the result of the
97 BOOL_BITFIELD need_temporary_p : 1;
98 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
99 from a pointer-to-derived to pointer-to-base is being performed. */
100 BOOL_BITFIELD base_p : 1;
101 /* If KIND is ck_ref_bind, true when either an lvalue reference is
102 being bound to an lvalue expression or an rvalue reference is
103 being bound to an rvalue expression. If KIND is ck_rvalue,
104 true when we should treat an lvalue as an rvalue (12.8p33). If
105 KIND is ck_base, always false. */
106 BOOL_BITFIELD rvaluedness_matches_p: 1;
107 BOOL_BITFIELD check_narrowing: 1;
108 /* The type of the expression resulting from the conversion. */
111 /* The next conversion in the chain. Since the conversions are
112 arranged from outermost to innermost, the NEXT conversion will
113 actually be performed before this conversion. This variant is
114 used only when KIND is neither ck_identity nor ck_ambig. */
116 /* The expression at the beginning of the conversion chain. This
117 variant is used only if KIND is ck_identity or ck_ambig. */
119 /* The array of conversions for an initializer_list. */
122 /* The function candidate corresponding to this conversion
123 sequence. This field is only used if KIND is ck_user. */
124 struct z_candidate *cand;
127 #define CONVERSION_RANK(NODE) \
128 ((NODE)->bad_p ? cr_bad \
129 : (NODE)->ellipsis_p ? cr_ellipsis \
130 : (NODE)->user_conv_p ? cr_user \
133 #define BAD_CONVERSION_RANK(NODE) \
134 ((NODE)->ellipsis_p ? cr_ellipsis \
135 : (NODE)->user_conv_p ? cr_user \
138 static struct obstack conversion_obstack;
139 static bool conversion_obstack_initialized;
140 struct rejection_reason;
142 static struct z_candidate * tourney (struct z_candidate *);
143 static int equal_functions (tree, tree);
144 static int joust (struct z_candidate *, struct z_candidate *, bool);
145 static int compare_ics (conversion *, conversion *);
146 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
147 static tree build_java_interface_fn_ref (tree, tree);
148 #define convert_like(CONV, EXPR, COMPLAIN) \
149 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
150 /*issue_conversion_warnings=*/true, \
151 /*c_cast_p=*/false, (COMPLAIN))
152 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
153 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
154 /*issue_conversion_warnings=*/true, \
155 /*c_cast_p=*/false, (COMPLAIN))
156 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
157 bool, tsubst_flags_t);
158 static void op_error (enum tree_code, enum tree_code, tree, tree,
160 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
161 static void print_z_candidate (const char *, struct z_candidate *);
162 static void print_z_candidates (location_t, struct z_candidate *);
163 static tree build_this (tree);
164 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
165 static bool any_strictly_viable (struct z_candidate *);
166 static struct z_candidate *add_template_candidate
167 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
168 tree, tree, tree, int, unification_kind_t);
169 static struct z_candidate *add_template_candidate_real
170 (struct z_candidate **, tree, tree, tree, tree, const VEC(tree,gc) *,
171 tree, tree, tree, int, tree, unification_kind_t);
172 static struct z_candidate *add_template_conv_candidate
173 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
175 static void add_builtin_candidates
176 (struct z_candidate **, enum tree_code, enum tree_code,
178 static void add_builtin_candidate
179 (struct z_candidate **, enum tree_code, enum tree_code,
180 tree, tree, tree, tree *, tree *, int);
181 static bool is_complete (tree);
182 static void build_builtin_candidate
183 (struct z_candidate **, tree, tree, tree, tree *, tree *,
185 static struct z_candidate *add_conv_candidate
186 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
188 static struct z_candidate *add_function_candidate
189 (struct z_candidate **, tree, tree, tree, const VEC(tree,gc) *, tree,
191 static conversion *implicit_conversion (tree, tree, tree, bool, int);
192 static conversion *standard_conversion (tree, tree, tree, bool, int);
193 static conversion *reference_binding (tree, tree, tree, bool, int);
194 static conversion *build_conv (conversion_kind, tree, conversion *);
195 static conversion *build_list_conv (tree, tree, int);
196 static bool is_subseq (conversion *, conversion *);
197 static conversion *maybe_handle_ref_bind (conversion **);
198 static void maybe_handle_implicit_object (conversion **);
199 static struct z_candidate *add_candidate
200 (struct z_candidate **, tree, tree, const VEC(tree,gc) *, size_t,
201 conversion **, tree, tree, int, struct rejection_reason *);
202 static tree source_type (conversion *);
203 static void add_warning (struct z_candidate *, struct z_candidate *);
204 static bool reference_compatible_p (tree, tree);
205 static conversion *convert_class_to_reference (tree, tree, tree, int);
206 static conversion *direct_reference_binding (tree, conversion *);
207 static bool promoted_arithmetic_type_p (tree);
208 static conversion *conditional_conversion (tree, tree);
209 static char *name_as_c_string (tree, tree, bool *);
210 static tree prep_operand (tree);
211 static void add_candidates (tree, tree, const VEC(tree,gc) *, tree, tree, bool,
212 tree, tree, int, struct z_candidate **);
213 static conversion *merge_conversion_sequences (conversion *, conversion *);
214 static bool magic_varargs_p (tree);
215 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
217 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
218 NAME can take many forms... */
221 check_dtor_name (tree basetype, tree name)
223 /* Just accept something we've already complained about. */
224 if (name == error_mark_node)
227 if (TREE_CODE (name) == TYPE_DECL)
228 name = TREE_TYPE (name);
229 else if (TYPE_P (name))
231 else if (TREE_CODE (name) == IDENTIFIER_NODE)
233 if ((MAYBE_CLASS_TYPE_P (basetype)
234 && name == constructor_name (basetype))
235 || (TREE_CODE (basetype) == ENUMERAL_TYPE
236 && name == TYPE_IDENTIFIER (basetype)))
239 name = get_type_value (name);
245 template <class T> struct S { ~S(); };
249 NAME will be a class template. */
250 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
254 if (!name || name == error_mark_node)
256 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
259 /* We want the address of a function or method. We avoid creating a
260 pointer-to-member function. */
263 build_addr_func (tree function)
265 tree type = TREE_TYPE (function);
267 /* We have to do these by hand to avoid real pointer to member
269 if (TREE_CODE (type) == METHOD_TYPE)
271 if (TREE_CODE (function) == OFFSET_REF)
273 tree object = build_address (TREE_OPERAND (function, 0));
274 return get_member_function_from_ptrfunc (&object,
275 TREE_OPERAND (function, 1));
277 function = build_address (function);
280 function = decay_conversion (function);
285 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
286 POINTER_TYPE to those. Note, pointer to member function types
287 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
288 two variants. build_call_a is the primitive taking an array of
289 arguments, while build_call_n is a wrapper that handles varargs. */
292 build_call_n (tree function, int n, ...)
295 return build_call_a (function, 0, NULL);
298 tree *argarray = XALLOCAVEC (tree, n);
303 for (i = 0; i < n; i++)
304 argarray[i] = va_arg (ap, tree);
306 return build_call_a (function, n, argarray);
311 build_call_a (tree function, int n, tree *argarray)
313 int is_constructor = 0;
320 function = build_addr_func (function);
322 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
323 fntype = TREE_TYPE (TREE_TYPE (function));
324 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
325 || TREE_CODE (fntype) == METHOD_TYPE);
326 result_type = TREE_TYPE (fntype);
327 /* An rvalue has no cv-qualifiers. */
328 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
329 result_type = cv_unqualified (result_type);
331 if (TREE_CODE (function) == ADDR_EXPR
332 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
334 decl = TREE_OPERAND (function, 0);
335 if (!TREE_USED (decl))
337 /* We invoke build_call directly for several library
338 functions. These may have been declared normally if
339 we're building libgcc, so we can't just check
341 gcc_assert (DECL_ARTIFICIAL (decl)
342 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
350 /* We check both the decl and the type; a function may be known not to
351 throw without being declared throw(). */
352 nothrow = ((decl && TREE_NOTHROW (decl))
353 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
355 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
356 current_function_returns_abnormally = 1;
358 if (decl && TREE_DEPRECATED (decl))
359 warn_deprecated_use (decl, NULL_TREE);
360 require_complete_eh_spec_types (fntype, decl);
362 if (decl && DECL_CONSTRUCTOR_P (decl))
365 /* Don't pass empty class objects by value. This is useful
366 for tags in STL, which are used to control overload resolution.
367 We don't need to handle other cases of copying empty classes. */
368 if (! decl || ! DECL_BUILT_IN (decl))
369 for (i = 0; i < n; i++)
370 if (is_empty_class (TREE_TYPE (argarray[i]))
371 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
373 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
374 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
378 function = build_call_array_loc (input_location,
379 result_type, function, n, argarray);
380 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
381 TREE_NOTHROW (function) = nothrow;
386 /* Build something of the form ptr->method (args)
387 or object.method (args). This can also build
388 calls to constructors, and find friends.
390 Member functions always take their class variable
393 INSTANCE is a class instance.
395 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
397 PARMS help to figure out what that NAME really refers to.
399 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
400 down to the real instance type to use for access checking. We need this
401 information to get protected accesses correct.
403 FLAGS is the logical disjunction of zero or more LOOKUP_
404 flags. See cp-tree.h for more info.
406 If this is all OK, calls build_function_call with the resolved
409 This function must also handle being called to perform
410 initialization, promotion/coercion of arguments, and
411 instantiation of default parameters.
413 Note that NAME may refer to an instance variable name. If
414 `operator()()' is defined for the type of that field, then we return
417 /* New overloading code. */
419 typedef struct z_candidate z_candidate;
421 typedef struct candidate_warning candidate_warning;
422 struct candidate_warning {
424 candidate_warning *next;
427 /* Information for providing diagnostics about why overloading failed. */
429 enum rejection_reason_code {
433 rr_bad_arg_conversion
436 struct conversion_info {
437 /* The index of the argument, 0-based. */
439 /* The type of the actual argument. */
441 /* The type of the formal argument. */
445 struct rejection_reason {
446 enum rejection_reason_code code;
448 /* Information about an arity mismatch. */
450 /* The expected number of arguments. */
452 /* The actual number of arguments in the call. */
454 /* Whether the call was a varargs call. */
457 /* Information about an argument conversion mismatch. */
458 struct conversion_info conversion;
459 /* Same, but for bad argument conversions. */
460 struct conversion_info bad_conversion;
465 /* The FUNCTION_DECL that will be called if this candidate is
466 selected by overload resolution. */
468 /* If not NULL_TREE, the first argument to use when calling this
471 /* The rest of the arguments to use when calling this function. If
472 there are no further arguments this may be NULL or it may be an
474 const VEC(tree,gc) *args;
475 /* The implicit conversion sequences for each of the arguments to
478 /* The number of implicit conversion sequences. */
480 /* If FN is a user-defined conversion, the standard conversion
481 sequence from the type returned by FN to the desired destination
483 conversion *second_conv;
485 struct rejection_reason *reason;
486 /* If FN is a member function, the binfo indicating the path used to
487 qualify the name of FN at the call site. This path is used to
488 determine whether or not FN is accessible if it is selected by
489 overload resolution. The DECL_CONTEXT of FN will always be a
490 (possibly improper) base of this binfo. */
492 /* If FN is a non-static member function, the binfo indicating the
493 subobject to which the `this' pointer should be converted if FN
494 is selected by overload resolution. The type pointed to the by
495 the `this' pointer must correspond to the most derived class
496 indicated by the CONVERSION_PATH. */
497 tree conversion_path;
500 candidate_warning *warnings;
504 /* Returns true iff T is a null pointer constant in the sense of
508 null_ptr_cst_p (tree t)
512 A null pointer constant is an integral constant expression
513 (_expr.const_) rvalue of integer type that evaluates to zero or
514 an rvalue of type std::nullptr_t. */
515 if (NULLPTR_TYPE_P (TREE_TYPE (t)))
517 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
519 if (cxx_dialect >= cxx0x)
521 t = fold_non_dependent_expr (t);
522 t = maybe_constant_value (t);
523 if (TREE_CONSTANT (t) && integer_zerop (t))
528 t = integral_constant_value (t);
530 if (integer_zerop (t) && !TREE_OVERFLOW (t))
537 /* Returns nonzero if PARMLIST consists of only default parms and/or
541 sufficient_parms_p (const_tree parmlist)
543 for (; parmlist && parmlist != void_list_node;
544 parmlist = TREE_CHAIN (parmlist))
545 if (!TREE_PURPOSE (parmlist))
550 /* Allocate N bytes of memory from the conversion obstack. The memory
551 is zeroed before being returned. */
554 conversion_obstack_alloc (size_t n)
557 if (!conversion_obstack_initialized)
559 gcc_obstack_init (&conversion_obstack);
560 conversion_obstack_initialized = true;
562 p = obstack_alloc (&conversion_obstack, n);
567 /* Allocate rejection reasons. */
569 static struct rejection_reason *
570 alloc_rejection (enum rejection_reason_code code)
572 struct rejection_reason *p;
573 p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p);
578 static struct rejection_reason *
579 arity_rejection (tree first_arg, int expected, int actual)
581 struct rejection_reason *r = alloc_rejection (rr_arity);
582 int adjust = first_arg != NULL_TREE;
583 r->u.arity.expected = expected - adjust;
584 r->u.arity.actual = actual - adjust;
588 static struct rejection_reason *
589 arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
591 struct rejection_reason *r = alloc_rejection (rr_arg_conversion);
592 int adjust = first_arg != NULL_TREE;
593 r->u.conversion.n_arg = n_arg - adjust;
594 r->u.conversion.from_type = from;
595 r->u.conversion.to_type = to;
599 static struct rejection_reason *
600 bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
602 struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion);
603 int adjust = first_arg != NULL_TREE;
604 r->u.bad_conversion.n_arg = n_arg - adjust;
605 r->u.bad_conversion.from_type = from;
606 r->u.bad_conversion.to_type = to;
610 /* Dynamically allocate a conversion. */
613 alloc_conversion (conversion_kind kind)
616 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
621 #ifdef ENABLE_CHECKING
623 /* Make sure that all memory on the conversion obstack has been
627 validate_conversion_obstack (void)
629 if (conversion_obstack_initialized)
630 gcc_assert ((obstack_next_free (&conversion_obstack)
631 == obstack_base (&conversion_obstack)));
634 #endif /* ENABLE_CHECKING */
636 /* Dynamically allocate an array of N conversions. */
639 alloc_conversions (size_t n)
641 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
645 build_conv (conversion_kind code, tree type, conversion *from)
648 conversion_rank rank = CONVERSION_RANK (from);
650 /* Note that the caller is responsible for filling in t->cand for
651 user-defined conversions. */
652 t = alloc_conversion (code);
675 t->user_conv_p = (code == ck_user || from->user_conv_p);
676 t->bad_p = from->bad_p;
681 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
682 specialization of std::initializer_list<T>, if such a conversion is
686 build_list_conv (tree type, tree ctor, int flags)
688 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
689 unsigned len = CONSTRUCTOR_NELTS (ctor);
690 conversion **subconvs = alloc_conversions (len);
695 /* Within a list-initialization we can have more user-defined
697 flags &= ~LOOKUP_NO_CONVERSION;
698 /* But no narrowing conversions. */
699 flags |= LOOKUP_NO_NARROWING;
701 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
704 = implicit_conversion (elttype, TREE_TYPE (val), val,
712 t = alloc_conversion (ck_list);
714 t->u.list = subconvs;
717 for (i = 0; i < len; ++i)
719 conversion *sub = subconvs[i];
720 if (sub->rank > t->rank)
722 if (sub->user_conv_p)
723 t->user_conv_p = true;
731 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
732 is a valid aggregate initializer for array type ATYPE. */
735 can_convert_array (tree atype, tree ctor, int flags)
738 tree elttype = TREE_TYPE (atype);
739 for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
741 tree val = CONSTRUCTOR_ELT (ctor, i)->value;
743 if (TREE_CODE (elttype) == ARRAY_TYPE
744 && TREE_CODE (val) == CONSTRUCTOR)
745 ok = can_convert_array (elttype, val, flags);
747 ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags);
754 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
755 aggregate class, if such a conversion is possible. */
758 build_aggr_conv (tree type, tree ctor, int flags)
760 unsigned HOST_WIDE_INT i = 0;
762 tree field = next_initializable_field (TYPE_FIELDS (type));
763 tree empty_ctor = NULL_TREE;
765 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
767 tree ftype = TREE_TYPE (field);
771 if (i < CONSTRUCTOR_NELTS (ctor))
772 val = CONSTRUCTOR_ELT (ctor, i)->value;
775 if (empty_ctor == NULL_TREE)
776 empty_ctor = build_constructor (init_list_type_node, NULL);
781 if (TREE_CODE (ftype) == ARRAY_TYPE
782 && TREE_CODE (val) == CONSTRUCTOR)
783 ok = can_convert_array (ftype, val, flags);
785 ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags);
790 if (TREE_CODE (type) == UNION_TYPE)
794 if (i < CONSTRUCTOR_NELTS (ctor))
797 c = alloc_conversion (ck_aggr);
800 c->user_conv_p = true;
805 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
806 array type, if such a conversion is possible. */
809 build_array_conv (tree type, tree ctor, int flags)
812 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
813 tree elttype = TREE_TYPE (type);
818 enum conversion_rank rank = cr_exact;
820 if (TYPE_DOMAIN (type))
822 unsigned HOST_WIDE_INT alen = tree_low_cst (array_type_nelts_top (type), 1);
827 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
830 = implicit_conversion (elttype, TREE_TYPE (val), val,
835 if (sub->rank > rank)
837 if (sub->user_conv_p)
843 c = alloc_conversion (ck_aggr);
846 c->user_conv_p = user;
852 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
853 complex type, if such a conversion is possible. */
856 build_complex_conv (tree type, tree ctor, int flags)
859 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
860 tree elttype = TREE_TYPE (type);
865 enum conversion_rank rank = cr_exact;
870 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
873 = implicit_conversion (elttype, TREE_TYPE (val), val,
878 if (sub->rank > rank)
880 if (sub->user_conv_p)
886 c = alloc_conversion (ck_aggr);
889 c->user_conv_p = user;
895 /* Build a representation of the identity conversion from EXPR to
896 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
899 build_identity_conv (tree type, tree expr)
903 c = alloc_conversion (ck_identity);
910 /* Converting from EXPR to TYPE was ambiguous in the sense that there
911 were multiple user-defined conversions to accomplish the job.
912 Build a conversion that indicates that ambiguity. */
915 build_ambiguous_conv (tree type, tree expr)
919 c = alloc_conversion (ck_ambig);
927 strip_top_quals (tree t)
929 if (TREE_CODE (t) == ARRAY_TYPE)
931 return cp_build_qualified_type (t, 0);
934 /* Returns the standard conversion path (see [conv]) from type FROM to type
935 TO, if any. For proper handling of null pointer constants, you must
936 also pass the expression EXPR to convert from. If C_CAST_P is true,
937 this conversion is coming from a C-style cast. */
940 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
943 enum tree_code fcode, tcode;
945 bool fromref = false;
948 to = non_reference (to);
949 if (TREE_CODE (from) == REFERENCE_TYPE)
952 from = TREE_TYPE (from);
955 to = strip_top_quals (to);
956 from = strip_top_quals (from);
958 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
959 && expr && type_unknown_p (expr))
961 tsubst_flags_t tflags = tf_conv;
962 if (!(flags & LOOKUP_PROTECT))
963 tflags |= tf_no_access_control;
964 expr = instantiate_type (to, expr, tflags);
965 if (expr == error_mark_node)
967 from = TREE_TYPE (expr);
970 fcode = TREE_CODE (from);
971 tcode = TREE_CODE (to);
973 conv = build_identity_conv (from, expr);
974 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
976 from = type_decays_to (from);
977 fcode = TREE_CODE (from);
978 conv = build_conv (ck_lvalue, from, conv);
980 else if (fromref || (expr && lvalue_p (expr)))
985 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
988 from = strip_top_quals (bitfield_type);
989 fcode = TREE_CODE (from);
992 conv = build_conv (ck_rvalue, from, conv);
993 if (flags & LOOKUP_PREFER_RVALUE)
994 conv->rvaluedness_matches_p = true;
997 /* Allow conversion between `__complex__' data types. */
998 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
1000 /* The standard conversion sequence to convert FROM to TO is
1001 the standard conversion sequence to perform componentwise
1003 conversion *part_conv = standard_conversion
1004 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
1008 conv = build_conv (part_conv->kind, to, conv);
1009 conv->rank = part_conv->rank;
1017 if (same_type_p (from, to))
1019 if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue)
1020 conv->type = qualified_to;
1025 A null pointer constant can be converted to a pointer type; ... A
1026 null pointer constant of integral type can be converted to an
1027 rvalue of type std::nullptr_t. */
1028 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to)
1029 || NULLPTR_TYPE_P (to))
1030 && expr && null_ptr_cst_p (expr))
1031 conv = build_conv (ck_std, to, conv);
1032 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
1033 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
1035 /* For backwards brain damage compatibility, allow interconversion of
1036 pointers and integers with a pedwarn. */
1037 conv = build_conv (ck_std, to, conv);
1040 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
1042 /* For backwards brain damage compatibility, allow interconversion of
1043 enums and integers with a pedwarn. */
1044 conv = build_conv (ck_std, to, conv);
1047 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
1048 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
1053 if (tcode == POINTER_TYPE
1054 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
1057 else if (VOID_TYPE_P (TREE_TYPE (to))
1058 && !TYPE_PTRMEM_P (from)
1059 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
1061 tree nfrom = TREE_TYPE (from);
1062 from = build_pointer_type
1063 (cp_build_qualified_type (void_type_node,
1064 cp_type_quals (nfrom)));
1065 conv = build_conv (ck_ptr, from, conv);
1067 else if (TYPE_PTRMEM_P (from))
1069 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
1070 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
1072 if (DERIVED_FROM_P (fbase, tbase)
1073 && (same_type_ignoring_top_level_qualifiers_p
1074 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
1075 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
1077 from = build_ptrmem_type (tbase,
1078 TYPE_PTRMEM_POINTED_TO_TYPE (from));
1079 conv = build_conv (ck_pmem, from, conv);
1081 else if (!same_type_p (fbase, tbase))
1084 else if (CLASS_TYPE_P (TREE_TYPE (from))
1085 && CLASS_TYPE_P (TREE_TYPE (to))
1088 An rvalue of type "pointer to cv D," where D is a
1089 class type, can be converted to an rvalue of type
1090 "pointer to cv B," where B is a base class (clause
1091 _class.derived_) of D. If B is an inaccessible
1092 (clause _class.access_) or ambiguous
1093 (_class.member.lookup_) base class of D, a program
1094 that necessitates this conversion is ill-formed.
1095 Therefore, we use DERIVED_FROM_P, and do not check
1096 access or uniqueness. */
1097 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
1100 cp_build_qualified_type (TREE_TYPE (to),
1101 cp_type_quals (TREE_TYPE (from)));
1102 from = build_pointer_type (from);
1103 conv = build_conv (ck_ptr, from, conv);
1104 conv->base_p = true;
1107 if (tcode == POINTER_TYPE)
1109 to_pointee = TREE_TYPE (to);
1110 from_pointee = TREE_TYPE (from);
1114 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
1115 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
1118 if (same_type_p (from, to))
1120 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
1121 /* In a C-style cast, we ignore CV-qualification because we
1122 are allowed to perform a static_cast followed by a
1124 conv = build_conv (ck_qual, to, conv);
1125 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
1126 conv = build_conv (ck_qual, to, conv);
1127 else if (expr && string_conv_p (to, expr, 0))
1128 /* converting from string constant to char *. */
1129 conv = build_conv (ck_qual, to, conv);
1130 /* Allow conversions among compatible ObjC pointer types (base
1131 conversions have been already handled above). */
1132 else if (c_dialect_objc ()
1133 && objc_compare_types (to, from, -4, NULL_TREE))
1134 conv = build_conv (ck_ptr, to, conv);
1135 else if (ptr_reasonably_similar (to_pointee, from_pointee))
1137 conv = build_conv (ck_ptr, to, conv);
1145 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
1147 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
1148 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
1149 tree fbase = class_of_this_parm (fromfn);
1150 tree tbase = class_of_this_parm (tofn);
1152 if (!DERIVED_FROM_P (fbase, tbase)
1153 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
1154 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
1155 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
1156 || cp_type_quals (fbase) != cp_type_quals (tbase))
1159 from = build_memfn_type (fromfn, tbase, cp_type_quals (tbase));
1160 from = build_ptrmemfunc_type (build_pointer_type (from));
1161 conv = build_conv (ck_pmem, from, conv);
1162 conv->base_p = true;
1164 else if (tcode == BOOLEAN_TYPE)
1168 An rvalue of arithmetic, unscoped enumeration, pointer, or
1169 pointer to member type can be converted to an rvalue of type
1170 bool. ... An rvalue of type std::nullptr_t can be converted
1171 to an rvalue of type bool; */
1172 if (ARITHMETIC_TYPE_P (from)
1173 || UNSCOPED_ENUM_P (from)
1174 || fcode == POINTER_TYPE
1175 || TYPE_PTR_TO_MEMBER_P (from)
1176 || NULLPTR_TYPE_P (from))
1178 conv = build_conv (ck_std, to, conv);
1179 if (fcode == POINTER_TYPE
1180 || TYPE_PTRMEM_P (from)
1181 || (TYPE_PTRMEMFUNC_P (from)
1182 && conv->rank < cr_pbool)
1183 || NULLPTR_TYPE_P (from))
1184 conv->rank = cr_pbool;
1190 /* We don't check for ENUMERAL_TYPE here because there are no standard
1191 conversions to enum type. */
1192 /* As an extension, allow conversion to complex type. */
1193 else if (ARITHMETIC_TYPE_P (to))
1195 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE)
1196 || SCOPED_ENUM_P (from))
1198 conv = build_conv (ck_std, to, conv);
1200 /* Give this a better rank if it's a promotion. */
1201 if (same_type_p (to, type_promotes_to (from))
1202 && conv->u.next->rank <= cr_promotion)
1203 conv->rank = cr_promotion;
1205 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
1206 && vector_types_convertible_p (from, to, false))
1207 return build_conv (ck_std, to, conv);
1208 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
1209 && is_properly_derived_from (from, to))
1211 if (conv->kind == ck_rvalue)
1212 conv = conv->u.next;
1213 conv = build_conv (ck_base, to, conv);
1214 /* The derived-to-base conversion indicates the initialization
1215 of a parameter with base type from an object of a derived
1216 type. A temporary object is created to hold the result of
1217 the conversion unless we're binding directly to a reference. */
1218 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
1223 if (flags & LOOKUP_NO_NARROWING)
1224 conv->check_narrowing = true;
1229 /* Returns nonzero if T1 is reference-related to T2. */
1232 reference_related_p (tree t1, tree t2)
1234 if (t1 == error_mark_node || t2 == error_mark_node)
1237 t1 = TYPE_MAIN_VARIANT (t1);
1238 t2 = TYPE_MAIN_VARIANT (t2);
1242 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1243 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1245 return (same_type_p (t1, t2)
1246 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1247 && DERIVED_FROM_P (t1, t2)));
1250 /* Returns nonzero if T1 is reference-compatible with T2. */
1253 reference_compatible_p (tree t1, tree t2)
1257 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1258 reference-related to T2 and cv1 is the same cv-qualification as,
1259 or greater cv-qualification than, cv2. */
1260 return (reference_related_p (t1, t2)
1261 && at_least_as_qualified_p (t1, t2));
1264 /* Determine whether or not the EXPR (of class type S) can be
1265 converted to T as in [over.match.ref]. */
1268 convert_class_to_reference_1 (tree reference_type, tree s, tree expr, int flags)
1274 struct z_candidate *candidates;
1275 struct z_candidate *cand;
1281 conversions = lookup_conversions (s);
1287 Assuming that "cv1 T" is the underlying type of the reference
1288 being initialized, and "cv S" is the type of the initializer
1289 expression, with S a class type, the candidate functions are
1290 selected as follows:
1292 --The conversion functions of S and its base classes are
1293 considered. Those that are not hidden within S and yield type
1294 "reference to cv2 T2", where "cv1 T" is reference-compatible
1295 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1297 The argument list has one argument, which is the initializer
1302 /* Conceptually, we should take the address of EXPR and put it in
1303 the argument list. Unfortunately, however, that can result in
1304 error messages, which we should not issue now because we are just
1305 trying to find a conversion operator. Therefore, we use NULL,
1306 cast to the appropriate type. */
1307 first_arg = build_int_cst (build_pointer_type (s), 0);
1309 t = TREE_TYPE (reference_type);
1311 /* We're performing a user-defined conversion to a desired type, so set
1312 this for the benefit of add_candidates. */
1313 flags |= LOOKUP_NO_CONVERSION;
1315 for (; conversions; conversions = TREE_CHAIN (conversions))
1317 tree fns = TREE_VALUE (conversions);
1318 tree binfo = TREE_PURPOSE (conversions);
1319 struct z_candidate *old_candidates = candidates;;
1321 add_candidates (fns, first_arg, NULL, reference_type,
1323 binfo, TYPE_BINFO (s),
1324 flags, &candidates);
1326 for (cand = candidates; cand != old_candidates; cand = cand->next)
1328 /* Now, see if the conversion function really returns
1329 an lvalue of the appropriate type. From the
1330 point of view of unification, simply returning an
1331 rvalue of the right type is good enough. */
1333 tree t2 = TREE_TYPE (TREE_TYPE (f));
1334 if (cand->viable == 0)
1335 /* Don't bother looking more closely. */;
1336 else if (TREE_CODE (t2) != REFERENCE_TYPE
1337 || !reference_compatible_p (t, TREE_TYPE (t2)))
1339 /* No need to set cand->reason here; this is most likely
1340 an ambiguous match. If it's not, either this candidate
1341 will win, or we will have identified a reason for it
1347 conversion *identity_conv;
1348 /* Build a standard conversion sequence indicating the
1349 binding from the reference type returned by the
1350 function to the desired REFERENCE_TYPE. */
1352 = build_identity_conv (TREE_TYPE (TREE_TYPE
1353 (TREE_TYPE (cand->fn))),
1356 = (direct_reference_binding
1357 (reference_type, identity_conv));
1358 cand->second_conv->rvaluedness_matches_p
1359 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1360 == TYPE_REF_IS_RVALUE (reference_type);
1361 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1363 /* Don't allow binding of lvalues to rvalue references. */
1364 if (TYPE_REF_IS_RVALUE (reference_type)
1365 && !TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn))))
1366 cand->second_conv->bad_p = true;
1371 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1372 /* If none of the conversion functions worked out, let our caller
1377 cand = tourney (candidates);
1381 /* Now that we know that this is the function we're going to use fix
1382 the dummy first argument. */
1383 gcc_assert (cand->first_arg == NULL_TREE
1384 || integer_zerop (cand->first_arg));
1385 cand->first_arg = build_this (expr);
1387 /* Build a user-defined conversion sequence representing the
1389 conv = build_conv (ck_user,
1390 TREE_TYPE (TREE_TYPE (cand->fn)),
1391 build_identity_conv (TREE_TYPE (expr), expr));
1394 if (cand->viable == -1)
1397 /* Merge it with the standard conversion sequence from the
1398 conversion function's return type to the desired type. */
1399 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1401 return cand->second_conv;
1404 /* Wrapper for above. */
1407 convert_class_to_reference (tree reference_type, tree s, tree expr, int flags)
1410 bool subtime = timevar_cond_start (TV_OVERLOAD);
1411 ret = convert_class_to_reference_1 (reference_type, s, expr, flags);
1412 timevar_cond_stop (TV_OVERLOAD, subtime);
1416 /* A reference of the indicated TYPE is being bound directly to the
1417 expression represented by the implicit conversion sequence CONV.
1418 Return a conversion sequence for this binding. */
1421 direct_reference_binding (tree type, conversion *conv)
1425 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1426 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1428 t = TREE_TYPE (type);
1432 When a parameter of reference type binds directly
1433 (_dcl.init.ref_) to an argument expression, the implicit
1434 conversion sequence is the identity conversion, unless the
1435 argument expression has a type that is a derived class of the
1436 parameter type, in which case the implicit conversion sequence is
1437 a derived-to-base Conversion.
1439 If the parameter binds directly to the result of applying a
1440 conversion function to the argument expression, the implicit
1441 conversion sequence is a user-defined conversion sequence
1442 (_over.ics.user_), with the second standard conversion sequence
1443 either an identity conversion or, if the conversion function
1444 returns an entity of a type that is a derived class of the
1445 parameter type, a derived-to-base conversion. */
1446 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1448 /* Represent the derived-to-base conversion. */
1449 conv = build_conv (ck_base, t, conv);
1450 /* We will actually be binding to the base-class subobject in
1451 the derived class, so we mark this conversion appropriately.
1452 That way, convert_like knows not to generate a temporary. */
1453 conv->need_temporary_p = false;
1455 return build_conv (ck_ref_bind, type, conv);
1458 /* Returns the conversion path from type FROM to reference type TO for
1459 purposes of reference binding. For lvalue binding, either pass a
1460 reference type to FROM or an lvalue expression to EXPR. If the
1461 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1462 the conversion returned. If C_CAST_P is true, this
1463 conversion is coming from a C-style cast. */
1466 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1468 conversion *conv = NULL;
1469 tree to = TREE_TYPE (rto);
1474 cp_lvalue_kind is_lvalue = clk_none;
1476 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1478 expr = instantiate_type (to, expr, tf_none);
1479 if (expr == error_mark_node)
1481 from = TREE_TYPE (expr);
1484 if (TREE_CODE (from) == REFERENCE_TYPE)
1486 /* Anything with reference type is an lvalue. */
1487 is_lvalue = clk_ordinary;
1488 from = TREE_TYPE (from);
1491 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1493 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1494 conv = implicit_conversion (to, from, expr, c_cast_p,
1496 if (!CLASS_TYPE_P (to)
1497 && CONSTRUCTOR_NELTS (expr) == 1)
1499 expr = CONSTRUCTOR_ELT (expr, 0)->value;
1500 if (error_operand_p (expr))
1502 from = TREE_TYPE (expr);
1506 if (is_lvalue == clk_none && expr)
1507 is_lvalue = real_lvalue_p (expr);
1510 if ((is_lvalue & clk_bitfield) != 0)
1511 tfrom = unlowered_expr_type (expr);
1513 /* Figure out whether or not the types are reference-related and
1514 reference compatible. We have do do this after stripping
1515 references from FROM. */
1516 related_p = reference_related_p (to, tfrom);
1517 /* If this is a C cast, first convert to an appropriately qualified
1518 type, so that we can later do a const_cast to the desired type. */
1519 if (related_p && c_cast_p
1520 && !at_least_as_qualified_p (to, tfrom))
1521 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1522 compatible_p = reference_compatible_p (to, tfrom);
1524 /* Directly bind reference when target expression's type is compatible with
1525 the reference and expression is an lvalue. In DR391, the wording in
1526 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1527 const and rvalue references to rvalues of compatible class type.
1528 We should also do direct bindings for non-class "rvalues" derived from
1529 rvalue references. */
1532 || (((CP_TYPE_CONST_NON_VOLATILE_P (to)
1533 && !(flags & LOOKUP_NO_TEMP_BIND))
1534 || TYPE_REF_IS_RVALUE (rto))
1535 && (CLASS_TYPE_P (from)
1536 || TREE_CODE (from) == ARRAY_TYPE
1537 || (expr && lvalue_p (expr))))))
1541 If the initializer expression
1543 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1544 is reference-compatible with "cv2 T2,"
1546 the reference is bound directly to the initializer expression
1550 If the initializer expression is an rvalue, with T2 a class type,
1551 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1552 is bound to the object represented by the rvalue or to a sub-object
1553 within that object. */
1555 conv = build_identity_conv (tfrom, expr);
1556 conv = direct_reference_binding (rto, conv);
1558 if (flags & LOOKUP_PREFER_RVALUE)
1559 /* The top-level caller requested that we pretend that the lvalue
1560 be treated as an rvalue. */
1561 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1563 conv->rvaluedness_matches_p
1564 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1566 if ((is_lvalue & clk_bitfield) != 0
1567 || ((is_lvalue & clk_packed) != 0 && !TYPE_PACKED (to)))
1568 /* For the purposes of overload resolution, we ignore the fact
1569 this expression is a bitfield or packed field. (In particular,
1570 [over.ics.ref] says specifically that a function with a
1571 non-const reference parameter is viable even if the
1572 argument is a bitfield.)
1574 However, when we actually call the function we must create
1575 a temporary to which to bind the reference. If the
1576 reference is volatile, or isn't const, then we cannot make
1577 a temporary, so we just issue an error when the conversion
1579 conv->need_temporary_p = true;
1581 /* Don't allow binding of lvalues (other than function lvalues) to
1582 rvalue references. */
1583 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1584 && TREE_CODE (to) != FUNCTION_TYPE
1585 && !(flags & LOOKUP_PREFER_RVALUE))
1590 /* [class.conv.fct] A conversion function is never used to convert a
1591 (possibly cv-qualified) object to the (possibly cv-qualified) same
1592 object type (or a reference to it), to a (possibly cv-qualified) base
1593 class of that type (or a reference to it).... */
1594 else if (CLASS_TYPE_P (from) && !related_p
1595 && !(flags & LOOKUP_NO_CONVERSION))
1599 If the initializer expression
1601 -- has a class type (i.e., T2 is a class type) can be
1602 implicitly converted to an lvalue of type "cv3 T3," where
1603 "cv1 T1" is reference-compatible with "cv3 T3". (this
1604 conversion is selected by enumerating the applicable
1605 conversion functions (_over.match.ref_) and choosing the
1606 best one through overload resolution. (_over.match_).
1608 the reference is bound to the lvalue result of the conversion
1609 in the second case. */
1610 conv = convert_class_to_reference (rto, from, expr, flags);
1615 /* From this point on, we conceptually need temporaries, even if we
1616 elide them. Only the cases above are "direct bindings". */
1617 if (flags & LOOKUP_NO_TEMP_BIND)
1622 When a parameter of reference type is not bound directly to an
1623 argument expression, the conversion sequence is the one required
1624 to convert the argument expression to the underlying type of the
1625 reference according to _over.best.ics_. Conceptually, this
1626 conversion sequence corresponds to copy-initializing a temporary
1627 of the underlying type with the argument expression. Any
1628 difference in top-level cv-qualification is subsumed by the
1629 initialization itself and does not constitute a conversion. */
1633 Otherwise, the reference shall be to a non-volatile const type.
1635 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1636 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1641 Otherwise, a temporary of type "cv1 T1" is created and
1642 initialized from the initializer expression using the rules for a
1643 non-reference copy initialization. If T1 is reference-related to
1644 T2, cv1 must be the same cv-qualification as, or greater
1645 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1646 if (related_p && !at_least_as_qualified_p (to, from))
1649 /* We're generating a temporary now, but don't bind any more in the
1650 conversion (specifically, don't slice the temporary returned by a
1651 conversion operator). */
1652 flags |= LOOKUP_NO_TEMP_BIND;
1654 /* Core issue 899: When [copy-]initializing a temporary to be bound
1655 to the first parameter of a copy constructor (12.8) called with
1656 a single argument in the context of direct-initialization,
1657 explicit conversion functions are also considered.
1659 So don't set LOOKUP_ONLYCONVERTING in that case. */
1660 if (!(flags & LOOKUP_COPY_PARM))
1661 flags |= LOOKUP_ONLYCONVERTING;
1664 conv = implicit_conversion (to, from, expr, c_cast_p,
1669 conv = build_conv (ck_ref_bind, rto, conv);
1670 /* This reference binding, unlike those above, requires the
1671 creation of a temporary. */
1672 conv->need_temporary_p = true;
1673 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1678 /* Returns the implicit conversion sequence (see [over.ics]) from type
1679 FROM to type TO. The optional expression EXPR may affect the
1680 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1681 true, this conversion is coming from a C-style cast. */
1684 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1689 if (from == error_mark_node || to == error_mark_node
1690 || expr == error_mark_node)
1693 if (TREE_CODE (to) == REFERENCE_TYPE)
1694 conv = reference_binding (to, from, expr, c_cast_p, flags);
1696 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1701 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1703 if (is_std_init_list (to))
1704 return build_list_conv (to, expr, flags);
1706 /* As an extension, allow list-initialization of _Complex. */
1707 if (TREE_CODE (to) == COMPLEX_TYPE)
1709 conv = build_complex_conv (to, expr, flags);
1714 /* Allow conversion from an initializer-list with one element to a
1716 if (SCALAR_TYPE_P (to))
1718 int nelts = CONSTRUCTOR_NELTS (expr);
1722 elt = build_value_init (to, tf_none);
1723 else if (nelts == 1)
1724 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1726 elt = error_mark_node;
1728 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1732 conv->check_narrowing = true;
1733 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1734 /* Too many levels of braces, i.e. '{{1}}'. */
1739 else if (TREE_CODE (to) == ARRAY_TYPE)
1740 return build_array_conv (to, expr, flags);
1743 if (expr != NULL_TREE
1744 && (MAYBE_CLASS_TYPE_P (from)
1745 || MAYBE_CLASS_TYPE_P (to))
1746 && (flags & LOOKUP_NO_CONVERSION) == 0)
1748 struct z_candidate *cand;
1749 int convflags = (flags & (LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING
1750 |LOOKUP_NO_NARROWING));
1752 if (CLASS_TYPE_P (to)
1753 && !CLASSTYPE_NON_AGGREGATE (complete_type (to))
1754 && BRACE_ENCLOSED_INITIALIZER_P (expr))
1755 return build_aggr_conv (to, expr, flags);
1757 cand = build_user_type_conversion_1 (to, expr, convflags);
1759 conv = cand->second_conv;
1761 /* We used to try to bind a reference to a temporary here, but that
1762 is now handled after the recursive call to this function at the end
1763 of reference_binding. */
1770 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1771 functions. ARGS will not be changed until a single candidate is
1774 static struct z_candidate *
1775 add_candidate (struct z_candidate **candidates,
1776 tree fn, tree first_arg, const VEC(tree,gc) *args,
1777 size_t num_convs, conversion **convs,
1778 tree access_path, tree conversion_path,
1779 int viable, struct rejection_reason *reason)
1781 struct z_candidate *cand = (struct z_candidate *)
1782 conversion_obstack_alloc (sizeof (struct z_candidate));
1785 cand->first_arg = first_arg;
1787 cand->convs = convs;
1788 cand->num_convs = num_convs;
1789 cand->access_path = access_path;
1790 cand->conversion_path = conversion_path;
1791 cand->viable = viable;
1792 cand->reason = reason;
1793 cand->next = *candidates;
1799 /* Return the number of remaining arguments in the parameter list
1800 beginning with ARG. */
1803 remaining_arguments (tree arg)
1807 for (n = 0; arg != NULL_TREE && arg != void_list_node;
1808 arg = TREE_CHAIN (arg))
1814 /* Create an overload candidate for the function or method FN called
1815 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1816 FLAGS is passed on to implicit_conversion.
1818 This does not change ARGS.
1820 CTYPE, if non-NULL, is the type we want to pretend this function
1821 comes from for purposes of overload resolution. */
1823 static struct z_candidate *
1824 add_function_candidate (struct z_candidate **candidates,
1825 tree fn, tree ctype, tree first_arg,
1826 const VEC(tree,gc) *args, tree access_path,
1827 tree conversion_path, int flags)
1829 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1833 tree orig_first_arg = first_arg;
1836 struct rejection_reason *reason = NULL;
1838 /* At this point we should not see any functions which haven't been
1839 explicitly declared, except for friend functions which will have
1840 been found using argument dependent lookup. */
1841 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1843 /* The `this', `in_chrg' and VTT arguments to constructors are not
1844 considered in overload resolution. */
1845 if (DECL_CONSTRUCTOR_P (fn))
1847 parmlist = skip_artificial_parms_for (fn, parmlist);
1848 skip = num_artificial_parms_for (fn);
1849 if (skip > 0 && first_arg != NULL_TREE)
1852 first_arg = NULL_TREE;
1858 len = VEC_length (tree, args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1859 convs = alloc_conversions (len);
1861 /* 13.3.2 - Viable functions [over.match.viable]
1862 First, to be a viable function, a candidate function shall have enough
1863 parameters to agree in number with the arguments in the list.
1865 We need to check this first; otherwise, checking the ICSes might cause
1866 us to produce an ill-formed template instantiation. */
1868 parmnode = parmlist;
1869 for (i = 0; i < len; ++i)
1871 if (parmnode == NULL_TREE || parmnode == void_list_node)
1873 parmnode = TREE_CHAIN (parmnode);
1876 if ((i < len && parmnode)
1877 || !sufficient_parms_p (parmnode))
1879 int remaining = remaining_arguments (parmnode);
1881 reason = arity_rejection (first_arg, i + remaining, len);
1883 /* When looking for a function from a subobject from an implicit
1884 copy/move constructor/operator=, don't consider anything that takes (a
1885 reference to) an unrelated type. See c++/44909 and core 1092. */
1886 else if (parmlist && (flags & LOOKUP_DEFAULTED))
1888 if (DECL_CONSTRUCTOR_P (fn))
1890 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
1891 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
1897 parmnode = chain_index (i-1, parmlist);
1898 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
1903 /* This only applies at the top level. */
1904 flags &= ~LOOKUP_DEFAULTED;
1910 /* Second, for F to be a viable function, there shall exist for each
1911 argument an implicit conversion sequence that converts that argument
1912 to the corresponding parameter of F. */
1914 parmnode = parmlist;
1916 for (i = 0; i < len; ++i)
1918 tree arg, argtype, to_type;
1922 if (parmnode == void_list_node)
1925 if (i == 0 && first_arg != NULL_TREE)
1928 arg = VEC_index (tree, args,
1929 i + skip - (first_arg != NULL_TREE ? 1 : 0));
1930 argtype = lvalue_type (arg);
1932 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1933 && ! DECL_CONSTRUCTOR_P (fn));
1937 tree parmtype = TREE_VALUE (parmnode);
1940 parmnode = TREE_CHAIN (parmnode);
1942 /* The type of the implicit object parameter ('this') for
1943 overload resolution is not always the same as for the
1944 function itself; conversion functions are considered to
1945 be members of the class being converted, and functions
1946 introduced by a using-declaration are considered to be
1947 members of the class that uses them.
1949 Since build_over_call ignores the ICS for the `this'
1950 parameter, we can just change the parm type. */
1951 if (ctype && is_this)
1953 parmtype = cp_build_qualified_type
1954 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
1955 parmtype = build_pointer_type (parmtype);
1958 /* Core issue 899: When [copy-]initializing a temporary to be bound
1959 to the first parameter of a copy constructor (12.8) called with
1960 a single argument in the context of direct-initialization,
1961 explicit conversion functions are also considered.
1963 So set LOOKUP_COPY_PARM to let reference_binding know that
1964 it's being called in that context. We generalize the above
1965 to handle move constructors and template constructors as well;
1966 the standardese should soon be updated similarly. */
1967 if (ctype && i == 0 && (len-skip == 1)
1968 && !(flags & LOOKUP_ONLYCONVERTING)
1969 && DECL_CONSTRUCTOR_P (fn)
1970 && parmtype != error_mark_node
1971 && (same_type_ignoring_top_level_qualifiers_p
1972 (non_reference (parmtype), ctype)))
1974 lflags |= LOOKUP_COPY_PARM;
1975 /* We allow user-defined conversions within init-lists, but
1976 not for the copy constructor. */
1977 if (flags & LOOKUP_NO_COPY_CTOR_CONVERSION)
1978 lflags |= LOOKUP_NO_CONVERSION;
1981 lflags |= LOOKUP_ONLYCONVERTING;
1983 t = implicit_conversion (parmtype, argtype, arg,
1984 /*c_cast_p=*/false, lflags);
1989 t = build_identity_conv (argtype, arg);
1990 t->ellipsis_p = true;
2001 reason = arg_conversion_rejection (first_arg, i, argtype, to_type);
2008 reason = bad_arg_conversion_rejection (first_arg, i, argtype, to_type);
2013 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
2014 access_path, conversion_path, viable, reason);
2017 /* Create an overload candidate for the conversion function FN which will
2018 be invoked for expression OBJ, producing a pointer-to-function which
2019 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2020 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2021 passed on to implicit_conversion.
2023 Actually, we don't really care about FN; we care about the type it
2024 converts to. There may be multiple conversion functions that will
2025 convert to that type, and we rely on build_user_type_conversion_1 to
2026 choose the best one; so when we create our candidate, we record the type
2027 instead of the function. */
2029 static struct z_candidate *
2030 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
2031 tree first_arg, const VEC(tree,gc) *arglist,
2032 tree access_path, tree conversion_path)
2034 tree totype = TREE_TYPE (TREE_TYPE (fn));
2035 int i, len, viable, flags;
2036 tree parmlist, parmnode;
2038 struct rejection_reason *reason;
2040 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
2041 parmlist = TREE_TYPE (parmlist);
2042 parmlist = TYPE_ARG_TYPES (parmlist);
2044 len = VEC_length (tree, arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
2045 convs = alloc_conversions (len);
2046 parmnode = parmlist;
2048 flags = LOOKUP_IMPLICIT;
2051 /* Don't bother looking up the same type twice. */
2052 if (*candidates && (*candidates)->fn == totype)
2055 for (i = 0; i < len; ++i)
2057 tree arg, argtype, convert_type = NULL_TREE;
2062 else if (i == 1 && first_arg != NULL_TREE)
2065 arg = VEC_index (tree, arglist,
2066 i - (first_arg != NULL_TREE ? 1 : 0) - 1);
2067 argtype = lvalue_type (arg);
2071 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
2073 convert_type = totype;
2075 else if (parmnode == void_list_node)
2079 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
2080 /*c_cast_p=*/false, flags);
2081 convert_type = TREE_VALUE (parmnode);
2085 t = build_identity_conv (argtype, arg);
2086 t->ellipsis_p = true;
2087 convert_type = argtype;
2097 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtype, convert_type);
2104 parmnode = TREE_CHAIN (parmnode);
2108 || ! sufficient_parms_p (parmnode))
2110 int remaining = remaining_arguments (parmnode);
2112 reason = arity_rejection (NULL_TREE, i + remaining, len);
2115 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
2116 access_path, conversion_path, viable, reason);
2120 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
2121 tree type1, tree type2, tree *args, tree *argtypes,
2129 struct rejection_reason *reason = NULL;
2134 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
2135 convs = alloc_conversions (num_convs);
2137 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2138 conversion ops are allowed. We handle that here by just checking for
2139 boolean_type_node because other operators don't ask for it. COND_EXPR
2140 also does contextual conversion to bool for the first operand, but we
2141 handle that in build_conditional_expr, and type1 here is operand 2. */
2142 if (type1 != boolean_type_node)
2143 flags |= LOOKUP_ONLYCONVERTING;
2145 for (i = 0; i < 2; ++i)
2150 t = implicit_conversion (types[i], argtypes[i], args[i],
2151 /*c_cast_p=*/false, flags);
2155 /* We need something for printing the candidate. */
2156 t = build_identity_conv (types[i], NULL_TREE);
2157 reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2162 reason = bad_arg_conversion_rejection (NULL_TREE, i, argtypes[i], types[i]);
2167 /* For COND_EXPR we rearranged the arguments; undo that now. */
2170 convs[2] = convs[1];
2171 convs[1] = convs[0];
2172 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
2173 /*c_cast_p=*/false, flags);
2179 reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2],
2184 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
2186 /*access_path=*/NULL_TREE,
2187 /*conversion_path=*/NULL_TREE,
2192 is_complete (tree t)
2194 return COMPLETE_TYPE_P (complete_type (t));
2197 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2200 promoted_arithmetic_type_p (tree type)
2204 In this section, the term promoted integral type is used to refer
2205 to those integral types which are preserved by integral promotion
2206 (including e.g. int and long but excluding e.g. char).
2207 Similarly, the term promoted arithmetic type refers to promoted
2208 integral types plus floating types. */
2209 return ((CP_INTEGRAL_TYPE_P (type)
2210 && same_type_p (type_promotes_to (type), type))
2211 || TREE_CODE (type) == REAL_TYPE);
2214 /* Create any builtin operator overload candidates for the operator in
2215 question given the converted operand types TYPE1 and TYPE2. The other
2216 args are passed through from add_builtin_candidates to
2217 build_builtin_candidate.
2219 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2220 If CODE is requires candidates operands of the same type of the kind
2221 of which TYPE1 and TYPE2 are, we add both candidates
2222 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2225 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
2226 enum tree_code code2, tree fnname, tree type1,
2227 tree type2, tree *args, tree *argtypes, int flags)
2231 case POSTINCREMENT_EXPR:
2232 case POSTDECREMENT_EXPR:
2233 args[1] = integer_zero_node;
2234 type2 = integer_type_node;
2243 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2244 and VQ is either volatile or empty, there exist candidate operator
2245 functions of the form
2246 VQ T& operator++(VQ T&);
2247 T operator++(VQ T&, int);
2248 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2249 type other than bool, and VQ is either volatile or empty, there exist
2250 candidate operator functions of the form
2251 VQ T& operator--(VQ T&);
2252 T operator--(VQ T&, int);
2253 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2254 complete object type, and VQ is either volatile or empty, there exist
2255 candidate operator functions of the form
2256 T*VQ& operator++(T*VQ&);
2257 T*VQ& operator--(T*VQ&);
2258 T* operator++(T*VQ&, int);
2259 T* operator--(T*VQ&, int); */
2261 case POSTDECREMENT_EXPR:
2262 case PREDECREMENT_EXPR:
2263 if (TREE_CODE (type1) == BOOLEAN_TYPE)
2265 case POSTINCREMENT_EXPR:
2266 case PREINCREMENT_EXPR:
2267 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
2269 type1 = build_reference_type (type1);
2274 /* 7 For every cv-qualified or cv-unqualified object type T, there
2275 exist candidate operator functions of the form
2279 8 For every function type T, there exist candidate operator functions of
2281 T& operator*(T*); */
2284 if (TREE_CODE (type1) == POINTER_TYPE
2285 && !uses_template_parms (TREE_TYPE (type1))
2286 && (TYPE_PTROB_P (type1)
2287 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
2291 /* 9 For every type T, there exist candidate operator functions of the form
2294 10For every promoted arithmetic type T, there exist candidate operator
2295 functions of the form
2299 case UNARY_PLUS_EXPR: /* unary + */
2300 if (TREE_CODE (type1) == POINTER_TYPE)
2303 if (ARITHMETIC_TYPE_P (type1))
2307 /* 11For every promoted integral type T, there exist candidate operator
2308 functions of the form
2312 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2316 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2317 is the same type as C2 or is a derived class of C2, T is a complete
2318 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2319 there exist candidate operator functions of the form
2320 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2321 where CV12 is the union of CV1 and CV2. */
2324 if (TREE_CODE (type1) == POINTER_TYPE
2325 && TYPE_PTR_TO_MEMBER_P (type2))
2327 tree c1 = TREE_TYPE (type1);
2328 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2330 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2331 && (TYPE_PTRMEMFUNC_P (type2)
2332 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2337 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2338 didate operator functions of the form
2343 bool operator<(L, R);
2344 bool operator>(L, R);
2345 bool operator<=(L, R);
2346 bool operator>=(L, R);
2347 bool operator==(L, R);
2348 bool operator!=(L, R);
2349 where LR is the result of the usual arithmetic conversions between
2352 14For every pair of types T and I, where T is a cv-qualified or cv-
2353 unqualified complete object type and I is a promoted integral type,
2354 there exist candidate operator functions of the form
2355 T* operator+(T*, I);
2356 T& operator[](T*, I);
2357 T* operator-(T*, I);
2358 T* operator+(I, T*);
2359 T& operator[](I, T*);
2361 15For every T, where T is a pointer to complete object type, there exist
2362 candidate operator functions of the form112)
2363 ptrdiff_t operator-(T, T);
2365 16For every pointer or enumeration type T, there exist candidate operator
2366 functions of the form
2367 bool operator<(T, T);
2368 bool operator>(T, T);
2369 bool operator<=(T, T);
2370 bool operator>=(T, T);
2371 bool operator==(T, T);
2372 bool operator!=(T, T);
2374 17For every pointer to member type T, there exist candidate operator
2375 functions of the form
2376 bool operator==(T, T);
2377 bool operator!=(T, T); */
2380 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2382 if (TYPE_PTROB_P (type1)
2383 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2385 type2 = ptrdiff_type_node;
2389 case TRUNC_DIV_EXPR:
2390 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2396 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2397 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
2399 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
2404 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
2416 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2418 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2420 if (TREE_CODE (type1) == ENUMERAL_TYPE
2421 && TREE_CODE (type2) == ENUMERAL_TYPE)
2423 if (TYPE_PTR_P (type1)
2424 && null_ptr_cst_p (args[1])
2425 && !uses_template_parms (type1))
2430 if (null_ptr_cst_p (args[0])
2431 && TYPE_PTR_P (type2)
2432 && !uses_template_parms (type2))
2440 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2443 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2445 type1 = ptrdiff_type_node;
2448 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2450 type2 = ptrdiff_type_node;
2455 /* 18For every pair of promoted integral types L and R, there exist candi-
2456 date operator functions of the form
2463 where LR is the result of the usual arithmetic conversions between
2466 case TRUNC_MOD_EXPR:
2472 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2476 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2477 type, VQ is either volatile or empty, and R is a promoted arithmetic
2478 type, there exist candidate operator functions of the form
2479 VQ L& operator=(VQ L&, R);
2480 VQ L& operator*=(VQ L&, R);
2481 VQ L& operator/=(VQ L&, R);
2482 VQ L& operator+=(VQ L&, R);
2483 VQ L& operator-=(VQ L&, R);
2485 20For every pair T, VQ), where T is any type and VQ is either volatile
2486 or empty, there exist candidate operator functions of the form
2487 T*VQ& operator=(T*VQ&, T*);
2489 21For every pair T, VQ), where T is a pointer to member type and VQ is
2490 either volatile or empty, there exist candidate operator functions of
2492 VQ T& operator=(VQ T&, T);
2494 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2495 unqualified complete object type, VQ is either volatile or empty, and
2496 I is a promoted integral type, there exist candidate operator func-
2498 T*VQ& operator+=(T*VQ&, I);
2499 T*VQ& operator-=(T*VQ&, I);
2501 23For every triple L, VQ, R), where L is an integral or enumeration
2502 type, VQ is either volatile or empty, and R is a promoted integral
2503 type, there exist candidate operator functions of the form
2505 VQ L& operator%=(VQ L&, R);
2506 VQ L& operator<<=(VQ L&, R);
2507 VQ L& operator>>=(VQ L&, R);
2508 VQ L& operator&=(VQ L&, R);
2509 VQ L& operator^=(VQ L&, R);
2510 VQ L& operator|=(VQ L&, R); */
2517 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2519 type2 = ptrdiff_type_node;
2523 case TRUNC_DIV_EXPR:
2524 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2528 case TRUNC_MOD_EXPR:
2534 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2539 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2541 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2542 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2543 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2544 || ((TYPE_PTRMEMFUNC_P (type1)
2545 || TREE_CODE (type1) == POINTER_TYPE)
2546 && null_ptr_cst_p (args[1])))
2556 type1 = build_reference_type (type1);
2562 For every pair of promoted arithmetic types L and R, there
2563 exist candidate operator functions of the form
2565 LR operator?(bool, L, R);
2567 where LR is the result of the usual arithmetic conversions
2568 between types L and R.
2570 For every type T, where T is a pointer or pointer-to-member
2571 type, there exist candidate operator functions of the form T
2572 operator?(bool, T, T); */
2574 if (promoted_arithmetic_type_p (type1)
2575 && promoted_arithmetic_type_p (type2))
2579 /* Otherwise, the types should be pointers. */
2580 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2581 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2584 /* We don't check that the two types are the same; the logic
2585 below will actually create two candidates; one in which both
2586 parameter types are TYPE1, and one in which both parameter
2592 if (ARITHMETIC_TYPE_P (type1))
2600 /* If we're dealing with two pointer types or two enumeral types,
2601 we need candidates for both of them. */
2602 if (type2 && !same_type_p (type1, type2)
2603 && TREE_CODE (type1) == TREE_CODE (type2)
2604 && (TREE_CODE (type1) == REFERENCE_TYPE
2605 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2606 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2607 || TYPE_PTRMEMFUNC_P (type1)
2608 || MAYBE_CLASS_TYPE_P (type1)
2609 || TREE_CODE (type1) == ENUMERAL_TYPE))
2611 build_builtin_candidate
2612 (candidates, fnname, type1, type1, args, argtypes, flags);
2613 build_builtin_candidate
2614 (candidates, fnname, type2, type2, args, argtypes, flags);
2618 build_builtin_candidate
2619 (candidates, fnname, type1, type2, args, argtypes, flags);
2623 type_decays_to (tree type)
2625 if (TREE_CODE (type) == ARRAY_TYPE)
2626 return build_pointer_type (TREE_TYPE (type));
2627 if (TREE_CODE (type) == FUNCTION_TYPE)
2628 return build_pointer_type (type);
2629 if (!MAYBE_CLASS_TYPE_P (type))
2630 type = cv_unqualified (type);
2634 /* There are three conditions of builtin candidates:
2636 1) bool-taking candidates. These are the same regardless of the input.
2637 2) pointer-pair taking candidates. These are generated for each type
2638 one of the input types converts to.
2639 3) arithmetic candidates. According to the standard, we should generate
2640 all of these, but I'm trying not to...
2642 Here we generate a superset of the possible candidates for this particular
2643 case. That is a subset of the full set the standard defines, plus some
2644 other cases which the standard disallows. add_builtin_candidate will
2645 filter out the invalid set. */
2648 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2649 enum tree_code code2, tree fnname, tree *args,
2654 tree type, argtypes[3], t;
2655 /* TYPES[i] is the set of possible builtin-operator parameter types
2656 we will consider for the Ith argument. */
2657 VEC(tree,gc) *types[2];
2660 for (i = 0; i < 3; ++i)
2663 argtypes[i] = unlowered_expr_type (args[i]);
2665 argtypes[i] = NULL_TREE;
2670 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2671 and VQ is either volatile or empty, there exist candidate operator
2672 functions of the form
2673 VQ T& operator++(VQ T&); */
2675 case POSTINCREMENT_EXPR:
2676 case PREINCREMENT_EXPR:
2677 case POSTDECREMENT_EXPR:
2678 case PREDECREMENT_EXPR:
2683 /* 24There also exist candidate operator functions of the form
2684 bool operator!(bool);
2685 bool operator&&(bool, bool);
2686 bool operator||(bool, bool); */
2688 case TRUTH_NOT_EXPR:
2689 build_builtin_candidate
2690 (candidates, fnname, boolean_type_node,
2691 NULL_TREE, args, argtypes, flags);
2694 case TRUTH_ORIF_EXPR:
2695 case TRUTH_ANDIF_EXPR:
2696 build_builtin_candidate
2697 (candidates, fnname, boolean_type_node,
2698 boolean_type_node, args, argtypes, flags);
2720 types[0] = make_tree_vector ();
2721 types[1] = make_tree_vector ();
2723 for (i = 0; i < 2; ++i)
2727 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2731 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2734 convs = lookup_conversions (argtypes[i]);
2736 if (code == COND_EXPR)
2738 if (real_lvalue_p (args[i]))
2739 VEC_safe_push (tree, gc, types[i],
2740 build_reference_type (argtypes[i]));
2742 VEC_safe_push (tree, gc, types[i],
2743 TYPE_MAIN_VARIANT (argtypes[i]));
2749 for (; convs; convs = TREE_CHAIN (convs))
2751 type = TREE_TYPE (convs);
2754 && (TREE_CODE (type) != REFERENCE_TYPE
2755 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2758 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2759 VEC_safe_push (tree, gc, types[i], type);
2761 type = non_reference (type);
2762 if (i != 0 || ! ref1)
2764 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2765 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2766 VEC_safe_push (tree, gc, types[i], type);
2767 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2768 type = type_promotes_to (type);
2771 if (! vec_member (type, types[i]))
2772 VEC_safe_push (tree, gc, types[i], type);
2777 if (code == COND_EXPR && real_lvalue_p (args[i]))
2778 VEC_safe_push (tree, gc, types[i],
2779 build_reference_type (argtypes[i]));
2780 type = non_reference (argtypes[i]);
2781 if (i != 0 || ! ref1)
2783 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2784 if (enum_p && UNSCOPED_ENUM_P (type))
2785 VEC_safe_push (tree, gc, types[i], type);
2786 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2787 type = type_promotes_to (type);
2789 VEC_safe_push (tree, gc, types[i], type);
2793 /* Run through the possible parameter types of both arguments,
2794 creating candidates with those parameter types. */
2795 FOR_EACH_VEC_ELT_REVERSE (tree, types[0], ix, t)
2800 if (!VEC_empty (tree, types[1]))
2801 FOR_EACH_VEC_ELT_REVERSE (tree, types[1], jx, u)
2802 add_builtin_candidate
2803 (candidates, code, code2, fnname, t,
2804 u, args, argtypes, flags);
2806 add_builtin_candidate
2807 (candidates, code, code2, fnname, t,
2808 NULL_TREE, args, argtypes, flags);
2811 release_tree_vector (types[0]);
2812 release_tree_vector (types[1]);
2816 /* If TMPL can be successfully instantiated as indicated by
2817 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2819 TMPL is the template. EXPLICIT_TARGS are any explicit template
2820 arguments. ARGLIST is the arguments provided at the call-site.
2821 This does not change ARGLIST. The RETURN_TYPE is the desired type
2822 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2823 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2824 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2826 static struct z_candidate*
2827 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2828 tree ctype, tree explicit_targs, tree first_arg,
2829 const VEC(tree,gc) *arglist, tree return_type,
2830 tree access_path, tree conversion_path,
2831 int flags, tree obj, unification_kind_t strict)
2833 int ntparms = DECL_NTPARMS (tmpl);
2834 tree targs = make_tree_vec (ntparms);
2835 unsigned int len = VEC_length (tree, arglist);
2836 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
2837 unsigned int skip_without_in_chrg = 0;
2838 tree first_arg_without_in_chrg = first_arg;
2839 tree *args_without_in_chrg;
2840 unsigned int nargs_without_in_chrg;
2841 unsigned int ia, ix;
2843 struct z_candidate *cand;
2846 struct rejection_reason *reason = NULL;
2848 /* We don't do deduction on the in-charge parameter, the VTT
2849 parameter or 'this'. */
2850 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2852 if (first_arg_without_in_chrg != NULL_TREE)
2853 first_arg_without_in_chrg = NULL_TREE;
2855 ++skip_without_in_chrg;
2858 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2859 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2860 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2862 if (first_arg_without_in_chrg != NULL_TREE)
2863 first_arg_without_in_chrg = NULL_TREE;
2865 ++skip_without_in_chrg;
2868 if (len < skip_without_in_chrg)
2871 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
2872 + (len - skip_without_in_chrg));
2873 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
2875 if (first_arg_without_in_chrg != NULL_TREE)
2877 args_without_in_chrg[ia] = first_arg_without_in_chrg;
2880 for (ix = skip_without_in_chrg;
2881 VEC_iterate (tree, arglist, ix, arg);
2884 args_without_in_chrg[ia] = arg;
2887 gcc_assert (ia == nargs_without_in_chrg);
2889 i = fn_type_unification (tmpl, explicit_targs, targs,
2890 args_without_in_chrg,
2891 nargs_without_in_chrg,
2892 return_type, strict, flags);
2897 fn = instantiate_template (tmpl, targs, tf_none);
2898 if (fn == error_mark_node)
2903 A member function template is never instantiated to perform the
2904 copy of a class object to an object of its class type.
2906 It's a little unclear what this means; the standard explicitly
2907 does allow a template to be used to copy a class. For example,
2912 template <class T> A(const T&);
2915 void g () { A a (f ()); }
2917 the member template will be used to make the copy. The section
2918 quoted above appears in the paragraph that forbids constructors
2919 whose only parameter is (a possibly cv-qualified variant of) the
2920 class type, and a logical interpretation is that the intent was
2921 to forbid the instantiation of member templates which would then
2923 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
2925 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2926 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2931 if (obj != NULL_TREE)
2932 /* Aha, this is a conversion function. */
2933 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
2934 access_path, conversion_path);
2936 cand = add_function_candidate (candidates, fn, ctype,
2937 first_arg, arglist, access_path,
2938 conversion_path, flags);
2939 if (DECL_TI_TEMPLATE (fn) != tmpl)
2940 /* This situation can occur if a member template of a template
2941 class is specialized. Then, instantiate_template might return
2942 an instantiation of the specialization, in which case the
2943 DECL_TI_TEMPLATE field will point at the original
2944 specialization. For example:
2946 template <class T> struct S { template <class U> void f(U);
2947 template <> void f(int) {}; };
2951 Here, TMPL will be template <class U> S<double>::f(U).
2952 And, instantiate template will give us the specialization
2953 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2954 for this will point at template <class T> template <> S<T>::f(int),
2955 so that we can find the definition. For the purposes of
2956 overload resolution, however, we want the original TMPL. */
2957 cand->template_decl = build_template_info (tmpl, targs);
2959 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2960 cand->explicit_targs = explicit_targs;
2964 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
2965 access_path, conversion_path, 0, reason);
2969 static struct z_candidate *
2970 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2971 tree explicit_targs, tree first_arg,
2972 const VEC(tree,gc) *arglist, tree return_type,
2973 tree access_path, tree conversion_path, int flags,
2974 unification_kind_t strict)
2977 add_template_candidate_real (candidates, tmpl, ctype,
2978 explicit_targs, first_arg, arglist,
2979 return_type, access_path, conversion_path,
2980 flags, NULL_TREE, strict);
2984 static struct z_candidate *
2985 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2986 tree obj, tree first_arg,
2987 const VEC(tree,gc) *arglist,
2988 tree return_type, tree access_path,
2989 tree conversion_path)
2992 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2993 first_arg, arglist, return_type, access_path,
2994 conversion_path, 0, obj, DEDUCE_CONV);
2997 /* The CANDS are the set of candidates that were considered for
2998 overload resolution. Return the set of viable candidates, or CANDS
2999 if none are viable. If any of the candidates were viable, set
3000 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3001 considered viable only if it is strictly viable. */
3003 static struct z_candidate*
3004 splice_viable (struct z_candidate *cands,
3008 struct z_candidate *viable;
3009 struct z_candidate **last_viable;
3010 struct z_candidate **cand;
3012 /* Be strict inside templates, since build_over_call won't actually
3013 do the conversions to get pedwarns. */
3014 if (processing_template_decl)
3018 last_viable = &viable;
3019 *any_viable_p = false;
3024 struct z_candidate *c = *cand;
3025 if (strict_p ? c->viable == 1 : c->viable)
3030 last_viable = &c->next;
3031 *any_viable_p = true;
3037 return viable ? viable : cands;
3041 any_strictly_viable (struct z_candidate *cands)
3043 for (; cands; cands = cands->next)
3044 if (cands->viable == 1)
3049 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3050 words, it is about to become the "this" pointer for a member
3051 function call. Take the address of the object. */
3054 build_this (tree obj)
3056 /* In a template, we are only concerned about the type of the
3057 expression, so we can take a shortcut. */
3058 if (processing_template_decl)
3059 return build_address (obj);
3061 return cp_build_addr_expr (obj, tf_warning_or_error);
3064 /* Returns true iff functions are equivalent. Equivalent functions are
3065 not '==' only if one is a function-local extern function or if
3066 both are extern "C". */
3069 equal_functions (tree fn1, tree fn2)
3071 if (TREE_CODE (fn1) != TREE_CODE (fn2))
3073 if (TREE_CODE (fn1) == TEMPLATE_DECL)
3075 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
3076 || DECL_EXTERN_C_FUNCTION_P (fn1))
3077 return decls_match (fn1, fn2);
3081 /* Print information about a candidate being rejected due to INFO. */
3084 print_conversion_rejection (location_t loc, struct conversion_info *info)
3086 if (info->n_arg == -1)
3087 /* Conversion of implicit `this' argument failed. */
3088 inform (loc, " no known conversion for implicit "
3089 "%<this%> parameter from %qT to %qT",
3090 info->from_type, info->to_type);
3092 inform (loc, " no known conversion for argument %d from %qT to %qT",
3093 info->n_arg+1, info->from_type, info->to_type);
3096 /* Print information about one overload candidate CANDIDATE. MSGSTR
3097 is the text to print before the candidate itself.
3099 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3100 to have been run through gettext by the caller. This wart makes
3101 life simpler in print_z_candidates and for the translators. */
3104 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
3106 const char *msg = (msgstr == NULL
3108 : ACONCAT ((msgstr, " ", NULL)));
3109 location_t loc = location_of (candidate->fn);
3111 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
3113 if (candidate->num_convs == 3)
3114 inform (input_location, "%s%D(%T, %T, %T) <built-in>", msg, candidate->fn,
3115 candidate->convs[0]->type,
3116 candidate->convs[1]->type,
3117 candidate->convs[2]->type);
3118 else if (candidate->num_convs == 2)
3119 inform (input_location, "%s%D(%T, %T) <built-in>", msg, candidate->fn,
3120 candidate->convs[0]->type,
3121 candidate->convs[1]->type);
3123 inform (input_location, "%s%D(%T) <built-in>", msg, candidate->fn,
3124 candidate->convs[0]->type);
3126 else if (TYPE_P (candidate->fn))
3127 inform (input_location, "%s%T <conversion>", msg, candidate->fn);
3128 else if (candidate->viable == -1)
3129 inform (loc, "%s%#D <near match>", msg, candidate->fn);
3130 else if (DECL_DELETED_FN (STRIP_TEMPLATE (candidate->fn)))
3131 inform (loc, "%s%#D <deleted>", msg, candidate->fn);
3133 inform (loc, "%s%#D", msg, candidate->fn);
3134 /* Give the user some information about why this candidate failed. */
3135 if (candidate->reason != NULL)
3137 struct rejection_reason *r = candidate->reason;
3142 inform_n (loc, r->u.arity.expected,
3143 " candidate expects %d argument, %d provided",
3144 " candidate expects %d arguments, %d provided",
3145 r->u.arity.expected, r->u.arity.actual);
3147 case rr_arg_conversion:
3148 print_conversion_rejection (loc, &r->u.conversion);
3150 case rr_bad_arg_conversion:
3151 print_conversion_rejection (loc, &r->u.bad_conversion);
3155 /* This candidate didn't have any issues or we failed to
3156 handle a particular code. Either way... */
3163 print_z_candidates (location_t loc, struct z_candidate *candidates)
3165 struct z_candidate *cand1;
3166 struct z_candidate **cand2;
3172 /* Remove non-viable deleted candidates. */
3174 for (cand2 = &cand1; *cand2; )
3176 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
3177 && !(*cand2)->viable
3178 && DECL_DELETED_FN ((*cand2)->fn))
3179 *cand2 = (*cand2)->next;
3181 cand2 = &(*cand2)->next;
3183 /* ...if there are any non-deleted ones. */
3187 /* There may be duplicates in the set of candidates. We put off
3188 checking this condition as long as possible, since we have no way
3189 to eliminate duplicates from a set of functions in less than n^2
3190 time. Now we are about to emit an error message, so it is more
3191 permissible to go slowly. */
3192 for (cand1 = candidates; cand1; cand1 = cand1->next)
3194 tree fn = cand1->fn;
3195 /* Skip builtin candidates and conversion functions. */
3198 cand2 = &cand1->next;
3201 if (DECL_P ((*cand2)->fn)
3202 && equal_functions (fn, (*cand2)->fn))
3203 *cand2 = (*cand2)->next;
3205 cand2 = &(*cand2)->next;
3209 for (n_candidates = 0, cand1 = candidates; cand1; cand1 = cand1->next)
3212 inform_n (loc, n_candidates, "candidate is:", "candidates are:");
3213 for (; candidates; candidates = candidates->next)
3214 print_z_candidate (NULL, candidates);
3217 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3218 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3219 the result of the conversion function to convert it to the final
3220 desired type. Merge the two sequences into a single sequence,
3221 and return the merged sequence. */
3224 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
3228 gcc_assert (user_seq->kind == ck_user);
3230 /* Find the end of the second conversion sequence. */
3232 while ((*t)->kind != ck_identity)
3233 t = &((*t)->u.next);
3235 /* Replace the identity conversion with the user conversion
3239 /* The entire sequence is a user-conversion sequence. */
3240 std_seq->user_conv_p = true;
3245 /* Handle overload resolution for initializing an object of class type from
3246 an initializer list. First we look for a suitable constructor that
3247 takes a std::initializer_list; if we don't find one, we then look for a
3248 non-list constructor.
3250 Parameters are as for add_candidates, except that the arguments are in
3251 the form of a CONSTRUCTOR (the initializer list) rather than a VEC, and
3252 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3255 add_list_candidates (tree fns, tree first_arg,
3256 tree init_list, tree totype,
3257 tree explicit_targs, bool template_only,
3258 tree conversion_path, tree access_path,
3260 struct z_candidate **candidates)
3264 gcc_assert (*candidates == NULL);
3266 /* For list-initialization we consider explicit constructors, but
3267 give an error if one is selected. */
3268 flags &= ~LOOKUP_ONLYCONVERTING;
3269 /* And we don't allow narrowing conversions. We also use this flag to
3270 avoid the copy constructor call for copy-list-initialization. */
3271 flags |= LOOKUP_NO_NARROWING;
3273 /* Always use the default constructor if the list is empty (DR 990). */
3274 if (CONSTRUCTOR_NELTS (init_list) == 0
3275 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
3277 /* If the class has a list ctor, try passing the list as a single
3278 argument first, but only consider list ctors. */
3279 else if (TYPE_HAS_LIST_CTOR (totype))
3281 flags |= LOOKUP_LIST_ONLY;
3282 args = make_tree_vector_single (init_list);
3283 add_candidates (fns, first_arg, args, NULL_TREE,
3284 explicit_targs, template_only, conversion_path,
3285 access_path, flags, candidates);
3286 if (any_strictly_viable (*candidates))
3290 args = ctor_to_vec (init_list);
3292 /* We aren't looking for list-ctors anymore. */
3293 flags &= ~LOOKUP_LIST_ONLY;
3294 /* We allow more user-defined conversions within an init-list. */
3295 flags &= ~LOOKUP_NO_CONVERSION;
3296 /* But not for the copy ctor. */
3297 flags |= LOOKUP_NO_COPY_CTOR_CONVERSION;
3299 add_candidates (fns, first_arg, args, NULL_TREE,
3300 explicit_targs, template_only, conversion_path,
3301 access_path, flags, candidates);
3304 /* Returns the best overload candidate to perform the requested
3305 conversion. This function is used for three the overloading situations
3306 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3307 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
3308 per [dcl.init.ref], so we ignore temporary bindings. */
3310 static struct z_candidate *
3311 build_user_type_conversion_1 (tree totype, tree expr, int flags)
3313 struct z_candidate *candidates, *cand;
3314 tree fromtype = TREE_TYPE (expr);
3315 tree ctors = NULL_TREE;
3316 tree conv_fns = NULL_TREE;
3317 conversion *conv = NULL;
3318 tree first_arg = NULL_TREE;
3319 VEC(tree,gc) *args = NULL;
3323 /* We represent conversion within a hierarchy using RVALUE_CONV and
3324 BASE_CONV, as specified by [over.best.ics]; these become plain
3325 constructor calls, as specified in [dcl.init]. */
3326 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
3327 || !DERIVED_FROM_P (totype, fromtype));
3329 if (MAYBE_CLASS_TYPE_P (totype))
3330 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3331 creating a garbage BASELINK; constructors can't be inherited. */
3332 ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
3334 if (MAYBE_CLASS_TYPE_P (fromtype))
3336 tree to_nonref = non_reference (totype);
3337 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
3338 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
3339 && DERIVED_FROM_P (to_nonref, fromtype)))
3341 /* [class.conv.fct] A conversion function is never used to
3342 convert a (possibly cv-qualified) object to the (possibly
3343 cv-qualified) same object type (or a reference to it), to a
3344 (possibly cv-qualified) base class of that type (or a
3345 reference to it)... */
3348 conv_fns = lookup_conversions (fromtype);
3352 flags |= LOOKUP_NO_CONVERSION;
3353 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3354 flags |= LOOKUP_NO_NARROWING;
3356 /* It's OK to bind a temporary for converting constructor arguments, but
3357 not in converting the return value of a conversion operator. */
3358 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION);
3359 flags &= ~LOOKUP_NO_TEMP_BIND;
3363 int ctorflags = flags;
3365 first_arg = build_int_cst (build_pointer_type (totype), 0);
3367 /* We should never try to call the abstract or base constructor
3369 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3370 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3372 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3374 /* List-initialization. */
3375 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3376 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3377 ctorflags, &candidates);
3381 args = make_tree_vector_single (expr);
3382 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3383 TYPE_BINFO (totype), TYPE_BINFO (totype),
3384 ctorflags, &candidates);
3387 for (cand = candidates; cand; cand = cand->next)
3389 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3391 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3392 set, then this is copy-initialization. In that case, "The
3393 result of the call is then used to direct-initialize the
3394 object that is the destination of the copy-initialization."
3397 We represent this in the conversion sequence with an
3398 rvalue conversion, which means a constructor call. */
3399 if (TREE_CODE (totype) != REFERENCE_TYPE
3400 && !(convflags & LOOKUP_NO_TEMP_BIND))
3402 = build_conv (ck_rvalue, totype, cand->second_conv);
3407 first_arg = build_this (expr);
3409 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3411 tree conversion_path = TREE_PURPOSE (conv_fns);
3412 struct z_candidate *old_candidates;
3414 /* If we are called to convert to a reference type, we are trying to
3415 find an lvalue binding, so don't even consider temporaries. If
3416 we don't find an lvalue binding, the caller will try again to
3417 look for a temporary binding. */
3418 if (TREE_CODE (totype) == REFERENCE_TYPE)
3419 convflags |= LOOKUP_NO_TEMP_BIND;
3421 old_candidates = candidates;
3422 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3424 conversion_path, TYPE_BINFO (fromtype),
3425 flags, &candidates);
3427 for (cand = candidates; cand != old_candidates; cand = cand->next)
3430 = implicit_conversion (totype,
3431 TREE_TYPE (TREE_TYPE (cand->fn)),
3433 /*c_cast_p=*/false, convflags);
3435 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3436 copy-initialization. In that case, "The result of the
3437 call is then used to direct-initialize the object that is
3438 the destination of the copy-initialization." [dcl.init]
3440 We represent this in the conversion sequence with an
3441 rvalue conversion, which means a constructor call. But
3442 don't add a second rvalue conversion if there's already
3443 one there. Which there really shouldn't be, but it's
3444 harmless since we'd add it here anyway. */
3445 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3446 && !(convflags & LOOKUP_NO_TEMP_BIND))
3447 ics = build_conv (ck_rvalue, totype, ics);
3449 cand->second_conv = ics;
3453 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3455 cand->reason = arg_conversion_rejection (NULL_TREE, -1,
3458 else if (cand->viable == 1 && ics->bad_p)
3460 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3463 = bad_arg_conversion_rejection (NULL_TREE, -1,
3469 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3473 release_tree_vector (args);
3477 cand = tourney (candidates);
3480 if (flags & LOOKUP_COMPLAIN)
3482 error ("conversion from %qT to %qT is ambiguous",
3484 print_z_candidates (location_of (expr), candidates);
3487 cand = candidates; /* any one will do */
3488 cand->second_conv = build_ambiguous_conv (totype, expr);
3489 cand->second_conv->user_conv_p = true;
3490 if (!any_strictly_viable (candidates))
3491 cand->second_conv->bad_p = true;
3492 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3493 ambiguous conversion is no worse than another user-defined
3499 /* Build the user conversion sequence. */
3502 (DECL_CONSTRUCTOR_P (cand->fn)
3503 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
3504 build_identity_conv (TREE_TYPE (expr), expr));
3507 /* Remember that this was a list-initialization. */
3508 if (flags & LOOKUP_NO_NARROWING)
3509 conv->check_narrowing = true;
3511 /* Combine it with the second conversion sequence. */
3512 cand->second_conv = merge_conversion_sequences (conv,
3515 if (cand->viable == -1)
3516 cand->second_conv->bad_p = true;
3521 /* Wrapper for above. */
3524 build_user_type_conversion (tree totype, tree expr, int flags)
3526 struct z_candidate *cand;
3529 bool subtime = timevar_cond_start (TV_OVERLOAD);
3530 cand = build_user_type_conversion_1 (totype, expr, flags);
3534 if (cand->second_conv->kind == ck_ambig)
3535 ret = error_mark_node;
3538 expr = convert_like (cand->second_conv, expr, tf_warning_or_error);
3539 ret = convert_from_reference (expr);
3545 timevar_cond_stop (TV_OVERLOAD, subtime);
3549 /* Subroutine of convert_nontype_argument.
3551 EXPR is an argument for a template non-type parameter of integral or
3552 enumeration type. Do any necessary conversions (that are permitted for
3553 non-type arguments) to convert it to the parameter type.
3555 If conversion is successful, returns the converted expression;
3556 otherwise, returns error_mark_node. */
3559 build_integral_nontype_arg_conv (tree type, tree expr, tsubst_flags_t complain)
3565 if (error_operand_p (expr))
3566 return error_mark_node;
3568 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
3570 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3571 p = conversion_obstack_alloc (0);
3573 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
3577 /* for a non-type template-parameter of integral or
3578 enumeration type, integral promotions (4.5) and integral
3579 conversions (4.7) are applied. */
3580 /* It should be sufficient to check the outermost conversion step, since
3581 there are no qualification conversions to integer type. */
3585 /* A conversion function is OK. If it isn't constexpr, we'll
3586 complain later that the argument isn't constant. */
3588 /* The lvalue-to-rvalue conversion is OK. */
3594 t = conv->u.next->type;
3595 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t))
3598 if (complain & tf_error)
3599 error ("conversion from %qT to %qT not considered for "
3600 "non-type template argument", t, type);
3601 /* and fall through. */
3609 expr = convert_like (conv, expr, complain);
3611 expr = error_mark_node;
3613 /* Free all the conversions we allocated. */
3614 obstack_free (&conversion_obstack, p);
3619 /* Do any initial processing on the arguments to a function call. */
3621 static VEC(tree,gc) *
3622 resolve_args (VEC(tree,gc) *args, tsubst_flags_t complain)
3627 FOR_EACH_VEC_ELT (tree, args, ix, arg)
3629 if (error_operand_p (arg))
3631 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3633 if (complain & tf_error)
3634 error ("invalid use of void expression");
3637 else if (invalid_nonstatic_memfn_p (arg, tf_warning_or_error))
3643 /* Perform overload resolution on FN, which is called with the ARGS.
3645 Return the candidate function selected by overload resolution, or
3646 NULL if the event that overload resolution failed. In the case
3647 that overload resolution fails, *CANDIDATES will be the set of
3648 candidates considered, and ANY_VIABLE_P will be set to true or
3649 false to indicate whether or not any of the candidates were
3652 The ARGS should already have gone through RESOLVE_ARGS before this
3653 function is called. */
3655 static struct z_candidate *
3656 perform_overload_resolution (tree fn,
3657 const VEC(tree,gc) *args,
3658 struct z_candidate **candidates,
3661 struct z_candidate *cand;
3662 tree explicit_targs;
3665 bool subtime = timevar_cond_start (TV_OVERLOAD);
3667 explicit_targs = NULL_TREE;
3671 *any_viable_p = true;
3674 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3675 || TREE_CODE (fn) == TEMPLATE_DECL
3676 || TREE_CODE (fn) == OVERLOAD
3677 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
3679 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3681 explicit_targs = TREE_OPERAND (fn, 1);
3682 fn = TREE_OPERAND (fn, 0);
3686 /* Add the various candidate functions. */
3687 add_candidates (fn, NULL_TREE, args, NULL_TREE,
3688 explicit_targs, template_only,
3689 /*conversion_path=*/NULL_TREE,
3690 /*access_path=*/NULL_TREE,
3694 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
3696 cand = tourney (*candidates);
3700 timevar_cond_stop (TV_OVERLOAD, subtime);
3704 /* Print an error message about being unable to build a call to FN with
3705 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
3706 be located; CANDIDATES is a possibly empty list of such
3710 print_error_for_call_failure (tree fn, VEC(tree,gc) *args, bool any_viable_p,
3711 struct z_candidate *candidates)
3713 tree name = DECL_NAME (OVL_CURRENT (fn));
3714 location_t loc = location_of (name);
3717 error_at (loc, "no matching function for call to %<%D(%A)%>",
3718 name, build_tree_list_vec (args));
3720 error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous",
3721 name, build_tree_list_vec (args));
3723 print_z_candidates (loc, candidates);
3726 /* Return an expression for a call to FN (a namespace-scope function,
3727 or a static member function) with the ARGS. This may change
3731 build_new_function_call (tree fn, VEC(tree,gc) **args, bool koenig_p,
3732 tsubst_flags_t complain)
3734 struct z_candidate *candidates, *cand;
3739 if (args != NULL && *args != NULL)
3741 *args = resolve_args (*args, complain);
3743 return error_mark_node;
3746 /* If this function was found without using argument dependent
3747 lookup, then we want to ignore any undeclared friend
3753 fn = remove_hidden_names (fn);
3756 if (complain & tf_error)
3757 print_error_for_call_failure (orig_fn, *args, false, NULL);
3758 return error_mark_node;
3762 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3763 p = conversion_obstack_alloc (0);
3765 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p);
3769 if (complain & tf_error)
3771 if (!any_viable_p && candidates && ! candidates->next
3772 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
3773 return cp_build_function_call_vec (candidates->fn, args, complain);
3774 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3775 fn = TREE_OPERAND (fn, 0);
3776 print_error_for_call_failure (fn, *args, any_viable_p, candidates);
3778 result = error_mark_node;
3782 int flags = LOOKUP_NORMAL;
3783 /* If fn is template_id_expr, the call has explicit template arguments
3784 (e.g. func<int>(5)), communicate this info to build_over_call
3785 through flags so that later we can use it to decide whether to warn
3786 about peculiar null pointer conversion. */
3787 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
3788 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
3789 result = build_over_call (cand, flags, complain);
3792 /* Free all the conversions we allocated. */
3793 obstack_free (&conversion_obstack, p);
3798 /* Build a call to a global operator new. FNNAME is the name of the
3799 operator (either "operator new" or "operator new[]") and ARGS are
3800 the arguments provided. This may change ARGS. *SIZE points to the
3801 total number of bytes required by the allocation, and is updated if
3802 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3803 be used. If this function determines that no cookie should be
3804 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3805 non-NULL, it will be set, upon return, to the allocation function
3809 build_operator_new_call (tree fnname, VEC(tree,gc) **args,
3810 tree *size, tree *cookie_size,
3814 struct z_candidate *candidates;
3815 struct z_candidate *cand;
3820 VEC_safe_insert (tree, gc, *args, 0, *size);
3821 *args = resolve_args (*args, tf_warning_or_error);
3823 return error_mark_node;
3829 If this lookup fails to find the name, or if the allocated type
3830 is not a class type, the allocation function's name is looked
3831 up in the global scope.
3833 we disregard block-scope declarations of "operator new". */
3834 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
3836 /* Figure out what function is being called. */
3837 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p);
3839 /* If no suitable function could be found, issue an error message
3843 print_error_for_call_failure (fns, *args, any_viable_p, candidates);
3844 return error_mark_node;
3847 /* If a cookie is required, add some extra space. Whether
3848 or not a cookie is required cannot be determined until
3849 after we know which function was called. */
3852 bool use_cookie = true;
3853 if (!abi_version_at_least (2))
3855 /* In G++ 3.2, the check was implemented incorrectly; it
3856 looked at the placement expression, rather than the
3857 type of the function. */
3858 if (VEC_length (tree, *args) == 2
3859 && same_type_p (TREE_TYPE (VEC_index (tree, *args, 1)),
3867 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
3868 /* Skip the size_t parameter. */
3869 arg_types = TREE_CHAIN (arg_types);
3870 /* Check the remaining parameters (if any). */
3872 && TREE_CHAIN (arg_types) == void_list_node
3873 && same_type_p (TREE_VALUE (arg_types),
3877 /* If we need a cookie, adjust the number of bytes allocated. */
3880 /* Update the total size. */
3881 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
3882 /* Update the argument list to reflect the adjusted size. */
3883 VEC_replace (tree, *args, 0, *size);
3886 *cookie_size = NULL_TREE;
3889 /* Tell our caller which function we decided to call. */
3893 /* Build the CALL_EXPR. */
3894 return build_over_call (cand, LOOKUP_NORMAL, tf_warning_or_error);
3897 /* Build a new call to operator(). This may change ARGS. */
3900 build_op_call_1 (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
3902 struct z_candidate *candidates = 0, *cand;
3903 tree fns, convs, first_mem_arg = NULL_TREE;
3904 tree type = TREE_TYPE (obj);
3906 tree result = NULL_TREE;
3909 if (error_operand_p (obj))
3910 return error_mark_node;
3912 obj = prep_operand (obj);
3914 if (TYPE_PTRMEMFUNC_P (type))
3916 if (complain & tf_error)
3917 /* It's no good looking for an overloaded operator() on a
3918 pointer-to-member-function. */
3919 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3920 return error_mark_node;
3923 if (TYPE_BINFO (type))
3925 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3926 if (fns == error_mark_node)
3927 return error_mark_node;
3932 if (args != NULL && *args != NULL)
3934 *args = resolve_args (*args, complain);
3936 return error_mark_node;
3939 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3940 p = conversion_obstack_alloc (0);
3944 first_mem_arg = build_this (obj);
3946 add_candidates (BASELINK_FUNCTIONS (fns),
3947 first_mem_arg, *args, NULL_TREE,
3949 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
3950 LOOKUP_NORMAL, &candidates);
3953 convs = lookup_conversions (type);
3955 for (; convs; convs = TREE_CHAIN (convs))
3957 tree fns = TREE_VALUE (convs);
3958 tree totype = TREE_TYPE (convs);
3960 if ((TREE_CODE (totype) == POINTER_TYPE
3961 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3962 || (TREE_CODE (totype) == REFERENCE_TYPE
3963 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3964 || (TREE_CODE (totype) == REFERENCE_TYPE
3965 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3966 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3967 for (; fns; fns = OVL_NEXT (fns))
3969 tree fn = OVL_CURRENT (fns);
3971 if (DECL_NONCONVERTING_P (fn))
3974 if (TREE_CODE (fn) == TEMPLATE_DECL)
3975 add_template_conv_candidate
3976 (&candidates, fn, obj, NULL_TREE, *args, totype,
3977 /*access_path=*/NULL_TREE,
3978 /*conversion_path=*/NULL_TREE);
3980 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
3981 *args, /*conversion_path=*/NULL_TREE,
3982 /*access_path=*/NULL_TREE);
3986 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3989 if (complain & tf_error)
3991 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
3992 build_tree_list_vec (*args));
3993 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
3995 result = error_mark_node;
3999 cand = tourney (candidates);
4002 if (complain & tf_error)
4004 error ("call of %<(%T) (%A)%> is ambiguous",
4005 TREE_TYPE (obj), build_tree_list_vec (*args));
4006 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4008 result = error_mark_node;
4010 /* Since cand->fn will be a type, not a function, for a conversion
4011 function, we must be careful not to unconditionally look at
4013 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
4014 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
4015 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4018 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
4020 obj = convert_from_reference (obj);
4021 result = cp_build_function_call_vec (obj, args, complain);
4025 /* Free all the conversions we allocated. */
4026 obstack_free (&conversion_obstack, p);
4031 /* Wrapper for above. */
4034 build_op_call (tree obj, VEC(tree,gc) **args, tsubst_flags_t complain)
4037 bool subtime = timevar_cond_start (TV_OVERLOAD);
4038 ret = build_op_call_1 (obj, args, complain);
4039 timevar_cond_stop (TV_OVERLOAD, subtime);
4044 op_error (enum tree_code code, enum tree_code code2,
4045 tree arg1, tree arg2, tree arg3, bool match)
4049 if (code == MODIFY_EXPR)
4050 opname = assignment_operator_name_info[code2].name;
4052 opname = operator_name_info[code].name;
4058 error ("ambiguous overload for ternary %<operator?:%> "
4059 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4061 error ("no match for ternary %<operator?:%> "
4062 "in %<%E ? %E : %E%>", arg1, arg2, arg3);
4065 case POSTINCREMENT_EXPR:
4066 case POSTDECREMENT_EXPR:
4068 error ("ambiguous overload for %<operator%s%> in %<%E%s%>",
4069 opname, arg1, opname);
4071 error ("no match for %<operator%s%> in %<%E%s%>",
4072 opname, arg1, opname);
4077 error ("ambiguous overload for %<operator[]%> in %<%E[%E]%>",
4080 error ("no match for %<operator[]%> in %<%E[%E]%>",
4087 error ("ambiguous overload for %qs in %<%s %E%>",
4088 opname, opname, arg1);
4090 error ("no match for %qs in %<%s %E%>",
4091 opname, opname, arg1);
4097 error ("ambiguous overload for %<operator%s%> in %<%E %s %E%>",
4098 opname, arg1, opname, arg2);
4100 error ("no match for %<operator%s%> in %<%E %s %E%>",
4101 opname, arg1, opname, arg2);
4104 error ("ambiguous overload for %<operator%s%> in %<%s%E%>",
4105 opname, opname, arg1);
4107 error ("no match for %<operator%s%> in %<%s%E%>",
4108 opname, opname, arg1);
4113 /* Return the implicit conversion sequence that could be used to
4114 convert E1 to E2 in [expr.cond]. */
4117 conditional_conversion (tree e1, tree e2)
4119 tree t1 = non_reference (TREE_TYPE (e1));
4120 tree t2 = non_reference (TREE_TYPE (e2));
4126 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4127 implicitly converted (clause _conv_) to the type "reference to
4128 T2", subject to the constraint that in the conversion the
4129 reference must bind directly (_dcl.init.ref_) to E1. */
4130 if (real_lvalue_p (e2))
4132 conv = implicit_conversion (build_reference_type (t2),
4136 LOOKUP_NO_TEMP_BIND|LOOKUP_ONLYCONVERTING);
4143 If E1 and E2 have class type, and the underlying class types are
4144 the same or one is a base class of the other: E1 can be converted
4145 to match E2 if the class of T2 is the same type as, or a base
4146 class of, the class of T1, and the cv-qualification of T2 is the
4147 same cv-qualification as, or a greater cv-qualification than, the
4148 cv-qualification of T1. If the conversion is applied, E1 is
4149 changed to an rvalue of type T2 that still refers to the original
4150 source class object (or the appropriate subobject thereof). */
4151 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
4152 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
4154 if (good_base && at_least_as_qualified_p (t2, t1))
4156 conv = build_identity_conv (t1, e1);
4157 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
4158 TYPE_MAIN_VARIANT (t2)))
4159 conv = build_conv (ck_base, t2, conv);
4161 conv = build_conv (ck_rvalue, t2, conv);
4170 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4171 converted to the type that expression E2 would have if E2 were
4172 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4173 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
4177 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4178 arguments to the conditional expression. */
4181 build_conditional_expr_1 (tree arg1, tree arg2, tree arg3,
4182 tsubst_flags_t complain)
4186 tree result = NULL_TREE;
4187 tree result_type = NULL_TREE;
4188 bool lvalue_p = true;
4189 struct z_candidate *candidates = 0;
4190 struct z_candidate *cand;
4193 /* As a G++ extension, the second argument to the conditional can be
4194 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4195 c'.) If the second operand is omitted, make sure it is
4196 calculated only once. */
4199 if (complain & tf_error)
4200 pedwarn (input_location, OPT_pedantic,
4201 "ISO C++ forbids omitting the middle term of a ?: expression");
4203 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4204 if (real_lvalue_p (arg1))
4205 arg2 = arg1 = stabilize_reference (arg1);
4207 arg2 = arg1 = save_expr (arg1);
4212 The first expression is implicitly converted to bool (clause
4214 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
4217 /* If something has already gone wrong, just pass that fact up the
4219 if (error_operand_p (arg1)
4220 || error_operand_p (arg2)
4221 || error_operand_p (arg3))
4222 return error_mark_node;
4226 If either the second or the third operand has type (possibly
4227 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4228 array-to-pointer (_conv.array_), and function-to-pointer
4229 (_conv.func_) standard conversions are performed on the second
4230 and third operands. */
4231 arg2_type = unlowered_expr_type (arg2);
4232 arg3_type = unlowered_expr_type (arg3);
4233 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
4235 /* Do the conversions. We don't these for `void' type arguments
4236 since it can't have any effect and since decay_conversion
4237 does not handle that case gracefully. */
4238 if (!VOID_TYPE_P (arg2_type))
4239 arg2 = decay_conversion (arg2);
4240 if (!VOID_TYPE_P (arg3_type))
4241 arg3 = decay_conversion (arg3);
4242 arg2_type = TREE_TYPE (arg2);
4243 arg3_type = TREE_TYPE (arg3);
4247 One of the following shall hold:
4249 --The second or the third operand (but not both) is a
4250 throw-expression (_except.throw_); the result is of the
4251 type of the other and is an rvalue.
4253 --Both the second and the third operands have type void; the
4254 result is of type void and is an rvalue.
4256 We must avoid calling force_rvalue for expressions of type
4257 "void" because it will complain that their value is being
4259 if (TREE_CODE (arg2) == THROW_EXPR
4260 && TREE_CODE (arg3) != THROW_EXPR)
4262 if (!VOID_TYPE_P (arg3_type))
4264 arg3 = force_rvalue (arg3, complain);
4265 if (arg3 == error_mark_node)
4266 return error_mark_node;
4268 arg3_type = TREE_TYPE (arg3);
4269 result_type = arg3_type;
4271 else if (TREE_CODE (arg2) != THROW_EXPR
4272 && TREE_CODE (arg3) == THROW_EXPR)
4274 if (!VOID_TYPE_P (arg2_type))
4276 arg2 = force_rvalue (arg2, complain);
4277 if (arg2 == error_mark_node)
4278 return error_mark_node;
4280 arg2_type = TREE_TYPE (arg2);
4281 result_type = arg2_type;
4283 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
4284 result_type = void_type_node;
4287 if (complain & tf_error)
4289 if (VOID_TYPE_P (arg2_type))
4290 error ("second operand to the conditional operator "
4291 "is of type %<void%>, "
4292 "but the third operand is neither a throw-expression "
4293 "nor of type %<void%>");
4295 error ("third operand to the conditional operator "
4296 "is of type %<void%>, "
4297 "but the second operand is neither a throw-expression "
4298 "nor of type %<void%>");
4300 return error_mark_node;
4304 goto valid_operands;
4308 Otherwise, if the second and third operand have different types,
4309 and either has (possibly cv-qualified) class type, an attempt is
4310 made to convert each of those operands to the type of the other. */
4311 else if (!same_type_p (arg2_type, arg3_type)
4312 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4317 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4318 p = conversion_obstack_alloc (0);
4320 conv2 = conditional_conversion (arg2, arg3);
4321 conv3 = conditional_conversion (arg3, arg2);
4325 If both can be converted, or one can be converted but the
4326 conversion is ambiguous, the program is ill-formed. If
4327 neither can be converted, the operands are left unchanged and
4328 further checking is performed as described below. If exactly
4329 one conversion is possible, that conversion is applied to the
4330 chosen operand and the converted operand is used in place of
4331 the original operand for the remainder of this section. */
4332 if ((conv2 && !conv2->bad_p
4333 && conv3 && !conv3->bad_p)
4334 || (conv2 && conv2->kind == ck_ambig)
4335 || (conv3 && conv3->kind == ck_ambig))
4337 error ("operands to ?: have different types %qT and %qT",
4338 arg2_type, arg3_type);
4339 result = error_mark_node;
4341 else if (conv2 && (!conv2->bad_p || !conv3))
4343 arg2 = convert_like (conv2, arg2, complain);
4344 arg2 = convert_from_reference (arg2);
4345 arg2_type = TREE_TYPE (arg2);
4346 /* Even if CONV2 is a valid conversion, the result of the
4347 conversion may be invalid. For example, if ARG3 has type
4348 "volatile X", and X does not have a copy constructor
4349 accepting a "volatile X&", then even if ARG2 can be
4350 converted to X, the conversion will fail. */
4351 if (error_operand_p (arg2))
4352 result = error_mark_node;
4354 else if (conv3 && (!conv3->bad_p || !conv2))
4356 arg3 = convert_like (conv3, arg3, complain);
4357 arg3 = convert_from_reference (arg3);
4358 arg3_type = TREE_TYPE (arg3);
4359 if (error_operand_p (arg3))
4360 result = error_mark_node;
4363 /* Free all the conversions we allocated. */
4364 obstack_free (&conversion_obstack, p);
4369 /* If, after the conversion, both operands have class type,
4370 treat the cv-qualification of both operands as if it were the
4371 union of the cv-qualification of the operands.
4373 The standard is not clear about what to do in this
4374 circumstance. For example, if the first operand has type
4375 "const X" and the second operand has a user-defined
4376 conversion to "volatile X", what is the type of the second
4377 operand after this step? Making it be "const X" (matching
4378 the first operand) seems wrong, as that discards the
4379 qualification without actually performing a copy. Leaving it
4380 as "volatile X" seems wrong as that will result in the
4381 conditional expression failing altogether, even though,
4382 according to this step, the one operand could be converted to
4383 the type of the other. */
4384 if ((conv2 || conv3)
4385 && CLASS_TYPE_P (arg2_type)
4386 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
4387 arg2_type = arg3_type =
4388 cp_build_qualified_type (arg2_type,
4389 cp_type_quals (arg2_type)
4390 | cp_type_quals (arg3_type));
4395 If the second and third operands are lvalues and have the same
4396 type, the result is of that type and is an lvalue. */
4397 if (real_lvalue_p (arg2)
4398 && real_lvalue_p (arg3)
4399 && same_type_p (arg2_type, arg3_type))
4401 result_type = arg2_type;
4402 arg2 = mark_lvalue_use (arg2);
4403 arg3 = mark_lvalue_use (arg3);
4404 goto valid_operands;
4409 Otherwise, the result is an rvalue. If the second and third
4410 operand do not have the same type, and either has (possibly
4411 cv-qualified) class type, overload resolution is used to
4412 determine the conversions (if any) to be applied to the operands
4413 (_over.match.oper_, _over.built_). */
4415 if (!same_type_p (arg2_type, arg3_type)
4416 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4422 /* Rearrange the arguments so that add_builtin_candidate only has
4423 to know about two args. In build_builtin_candidate, the
4424 arguments are unscrambled. */
4428 add_builtin_candidates (&candidates,
4431 ansi_opname (COND_EXPR),
4437 If the overload resolution fails, the program is
4439 candidates = splice_viable (candidates, pedantic, &any_viable_p);
4442 if (complain & tf_error)
4444 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4445 print_z_candidates (location_of (arg1), candidates);
4447 return error_mark_node;
4449 cand = tourney (candidates);
4452 if (complain & tf_error)
4454 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4455 print_z_candidates (location_of (arg1), candidates);
4457 return error_mark_node;
4462 Otherwise, the conversions thus determined are applied, and
4463 the converted operands are used in place of the original
4464 operands for the remainder of this section. */
4465 conv = cand->convs[0];
4466 arg1 = convert_like (conv, arg1, complain);
4467 conv = cand->convs[1];
4468 arg2 = convert_like (conv, arg2, complain);
4469 arg2_type = TREE_TYPE (arg2);
4470 conv = cand->convs[2];
4471 arg3 = convert_like (conv, arg3, complain);
4472 arg3_type = TREE_TYPE (arg3);
4477 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
4478 and function-to-pointer (_conv.func_) standard conversions are
4479 performed on the second and third operands.
4481 We need to force the lvalue-to-rvalue conversion here for class types,
4482 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
4483 that isn't wrapped with a TARGET_EXPR plays havoc with exception
4486 arg2 = force_rvalue (arg2, complain);
4487 if (!CLASS_TYPE_P (arg2_type))
4488 arg2_type = TREE_TYPE (arg2);
4490 arg3 = force_rvalue (arg3, complain);
4491 if (!CLASS_TYPE_P (arg3_type))
4492 arg3_type = TREE_TYPE (arg3);
4494 if (arg2 == error_mark_node || arg3 == error_mark_node)
4495 return error_mark_node;
4499 After those conversions, one of the following shall hold:
4501 --The second and third operands have the same type; the result is of
4503 if (same_type_p (arg2_type, arg3_type))
4504 result_type = arg2_type;
4507 --The second and third operands have arithmetic or enumeration
4508 type; the usual arithmetic conversions are performed to bring
4509 them to a common type, and the result is of that type. */
4510 else if ((ARITHMETIC_TYPE_P (arg2_type)
4511 || UNSCOPED_ENUM_P (arg2_type))
4512 && (ARITHMETIC_TYPE_P (arg3_type)
4513 || UNSCOPED_ENUM_P (arg3_type)))
4515 /* In this case, there is always a common type. */
4516 result_type = type_after_usual_arithmetic_conversions (arg2_type,
4518 do_warn_double_promotion (result_type, arg2_type, arg3_type,
4519 "implicit conversion from %qT to %qT to "
4520 "match other result of conditional",
4523 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
4524 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
4526 if (complain & tf_warning)
4528 "enumeral mismatch in conditional expression: %qT vs %qT",
4529 arg2_type, arg3_type);
4531 else if (extra_warnings
4532 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
4533 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
4534 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
4535 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
4537 if (complain & tf_warning)
4539 "enumeral and non-enumeral type in conditional expression");
4542 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4543 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4547 --The second and third operands have pointer type, or one has
4548 pointer type and the other is a null pointer constant; pointer
4549 conversions (_conv.ptr_) and qualification conversions
4550 (_conv.qual_) are performed to bring them to their composite
4551 pointer type (_expr.rel_). The result is of the composite
4554 --The second and third operands have pointer to member type, or
4555 one has pointer to member type and the other is a null pointer
4556 constant; pointer to member conversions (_conv.mem_) and
4557 qualification conversions (_conv.qual_) are performed to bring
4558 them to a common type, whose cv-qualification shall match the
4559 cv-qualification of either the second or the third operand.
4560 The result is of the common type. */
4561 else if ((null_ptr_cst_p (arg2)
4562 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
4563 || (null_ptr_cst_p (arg3)
4564 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
4565 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
4566 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
4567 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
4569 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
4570 arg3, CPO_CONDITIONAL_EXPR,
4572 if (result_type == error_mark_node)
4573 return error_mark_node;
4574 arg2 = perform_implicit_conversion (result_type, arg2, complain);
4575 arg3 = perform_implicit_conversion (result_type, arg3, complain);
4580 if (complain & tf_error)
4581 error ("operands to ?: have different types %qT and %qT",
4582 arg2_type, arg3_type);
4583 return error_mark_node;
4587 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
4588 if (!cp_unevaluated_operand)
4589 /* Avoid folding within decltype (c++/42013) and noexcept. */
4590 result = fold_if_not_in_template (result);
4592 /* We can't use result_type below, as fold might have returned a
4597 /* Expand both sides into the same slot, hopefully the target of
4598 the ?: expression. We used to check for TARGET_EXPRs here,
4599 but now we sometimes wrap them in NOP_EXPRs so the test would
4601 if (CLASS_TYPE_P (TREE_TYPE (result)))
4602 result = get_target_expr (result);
4603 /* If this expression is an rvalue, but might be mistaken for an
4604 lvalue, we must add a NON_LVALUE_EXPR. */
4605 result = rvalue (result);
4611 /* Wrapper for above. */
4614 build_conditional_expr (tree arg1, tree arg2, tree arg3,
4615 tsubst_flags_t complain)
4618 bool subtime = timevar_cond_start (TV_OVERLOAD);
4619 ret = build_conditional_expr_1 (arg1, arg2, arg3, complain);
4620 timevar_cond_stop (TV_OVERLOAD, subtime);
4624 /* OPERAND is an operand to an expression. Perform necessary steps
4625 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4629 prep_operand (tree operand)
4633 if (CLASS_TYPE_P (TREE_TYPE (operand))
4634 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
4635 /* Make sure the template type is instantiated now. */
4636 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
4642 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4643 OVERLOAD) to the CANDIDATES, returning an updated list of
4644 CANDIDATES. The ARGS are the arguments provided to the call;
4645 if FIRST_ARG is non-null it is the implicit object argument,
4646 otherwise the first element of ARGS is used if needed. The
4647 EXPLICIT_TARGS are explicit template arguments provided.
4648 TEMPLATE_ONLY is true if only template functions should be
4649 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4650 add_function_candidate. */
4653 add_candidates (tree fns, tree first_arg, const VEC(tree,gc) *args,
4655 tree explicit_targs, bool template_only,
4656 tree conversion_path, tree access_path,
4658 struct z_candidate **candidates)
4661 const VEC(tree,gc) *non_static_args;
4662 bool check_list_ctor;
4663 bool check_converting;
4664 unification_kind_t strict;
4670 /* Precalculate special handling of constructors and conversion ops. */
4671 fn = OVL_CURRENT (fns);
4672 if (DECL_CONV_FN_P (fn))
4674 check_list_ctor = false;
4675 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4676 if (flags & LOOKUP_NO_CONVERSION)
4677 /* We're doing return_type(x). */
4678 strict = DEDUCE_CONV;
4680 /* We're doing x.operator return_type(). */
4681 strict = DEDUCE_EXACT;
4682 /* [over.match.funcs] For conversion functions, the function
4683 is considered to be a member of the class of the implicit
4684 object argument for the purpose of defining the type of
4685 the implicit object parameter. */
4686 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (first_arg)));
4690 if (DECL_CONSTRUCTOR_P (fn))
4692 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
4693 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
4697 check_list_ctor = false;
4698 check_converting = false;
4700 strict = DEDUCE_CALL;
4701 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
4705 non_static_args = args;
4707 /* Delay creating the implicit this parameter until it is needed. */
4708 non_static_args = NULL;
4710 for (; fns; fns = OVL_NEXT (fns))
4713 const VEC(tree,gc) *fn_args;
4715 fn = OVL_CURRENT (fns);
4717 if (check_converting && DECL_NONCONVERTING_P (fn))
4719 if (check_list_ctor && !is_list_ctor (fn))
4722 /* Figure out which set of arguments to use. */
4723 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
4725 /* If this function is a non-static member and we didn't get an
4726 implicit object argument, move it out of args. */
4727 if (first_arg == NULL_TREE)
4731 VEC(tree,gc) *tempvec
4732 = VEC_alloc (tree, gc, VEC_length (tree, args) - 1);
4733 for (ix = 1; VEC_iterate (tree, args, ix, arg); ++ix)
4734 VEC_quick_push (tree, tempvec, arg);
4735 non_static_args = tempvec;
4736 first_arg = build_this (VEC_index (tree, args, 0));
4739 fn_first_arg = first_arg;
4740 fn_args = non_static_args;
4744 /* Otherwise, just use the list of arguments provided. */
4745 fn_first_arg = NULL_TREE;
4749 if (TREE_CODE (fn) == TEMPLATE_DECL)
4750 add_template_candidate (candidates,
4761 else if (!template_only)
4762 add_function_candidate (candidates,
4773 /* Even unsigned enum types promote to signed int. We don't want to
4774 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4775 original argument and ARG is the argument after any conversions
4776 have been applied. We set TREE_NO_WARNING if we have added a cast
4777 from an unsigned enum type to a signed integer type. */
4780 avoid_sign_compare_warnings (tree orig_arg, tree arg)
4782 if (orig_arg != NULL_TREE
4785 && TREE_CODE (TREE_TYPE (orig_arg)) == ENUMERAL_TYPE
4786 && TYPE_UNSIGNED (TREE_TYPE (orig_arg))
4787 && INTEGRAL_TYPE_P (TREE_TYPE (arg))
4788 && !TYPE_UNSIGNED (TREE_TYPE (arg)))
4789 TREE_NO_WARNING (arg) = 1;
4793 build_new_op_1 (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
4794 tree *overload, tsubst_flags_t complain)
4796 tree orig_arg1 = arg1;
4797 tree orig_arg2 = arg2;
4798 tree orig_arg3 = arg3;
4799 struct z_candidate *candidates = 0, *cand;
4800 VEC(tree,gc) *arglist;
4803 tree result = NULL_TREE;
4804 bool result_valid_p = false;
4805 enum tree_code code2 = NOP_EXPR;
4806 enum tree_code code_orig_arg1 = ERROR_MARK;
4807 enum tree_code code_orig_arg2 = ERROR_MARK;
4813 if (error_operand_p (arg1)
4814 || error_operand_p (arg2)
4815 || error_operand_p (arg3))
4816 return error_mark_node;
4818 if (code == MODIFY_EXPR)
4820 code2 = TREE_CODE (arg3);
4822 fnname = ansi_assopname (code2);
4825 fnname = ansi_opname (code);
4827 arg1 = prep_operand (arg1);
4833 case VEC_DELETE_EXPR:
4835 /* Use build_op_new_call and build_op_delete_call instead. */
4839 /* Use build_op_call instead. */
4842 case TRUTH_ORIF_EXPR:
4843 case TRUTH_ANDIF_EXPR:
4844 case TRUTH_AND_EXPR:
4846 /* These are saved for the sake of warn_logical_operator. */
4847 code_orig_arg1 = TREE_CODE (arg1);
4848 code_orig_arg2 = TREE_CODE (arg2);
4854 arg2 = prep_operand (arg2);
4855 arg3 = prep_operand (arg3);
4857 if (code == COND_EXPR)
4858 /* Use build_conditional_expr instead. */
4860 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
4861 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
4864 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
4865 arg2 = integer_zero_node;
4867 arglist = VEC_alloc (tree, gc, 3);
4868 VEC_quick_push (tree, arglist, arg1);
4869 if (arg2 != NULL_TREE)
4870 VEC_quick_push (tree, arglist, arg2);
4871 if (arg3 != NULL_TREE)
4872 VEC_quick_push (tree, arglist, arg3);
4874 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4875 p = conversion_obstack_alloc (0);
4877 /* Add namespace-scope operators to the list of functions to
4879 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
4880 NULL_TREE, arglist, NULL_TREE,
4881 NULL_TREE, false, NULL_TREE, NULL_TREE,
4882 flags, &candidates);
4883 /* Add class-member operators to the candidate set. */
4884 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
4888 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
4889 if (fns == error_mark_node)
4891 result = error_mark_node;
4892 goto user_defined_result_ready;
4895 add_candidates (BASELINK_FUNCTIONS (fns),
4896 NULL_TREE, arglist, NULL_TREE,
4898 BASELINK_BINFO (fns),
4899 BASELINK_ACCESS_BINFO (fns),
4900 flags, &candidates);
4905 args[2] = NULL_TREE;
4907 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
4913 /* For these, the built-in candidates set is empty
4914 [over.match.oper]/3. We don't want non-strict matches
4915 because exact matches are always possible with built-in
4916 operators. The built-in candidate set for COMPONENT_REF
4917 would be empty too, but since there are no such built-in
4918 operators, we accept non-strict matches for them. */
4923 strict_p = pedantic;
4927 candidates = splice_viable (candidates, strict_p, &any_viable_p);
4932 case POSTINCREMENT_EXPR:
4933 case POSTDECREMENT_EXPR:
4934 /* Don't try anything fancy if we're not allowed to produce
4936 if (!(complain & tf_error))
4937 return error_mark_node;
4939 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4940 distinguish between prefix and postfix ++ and
4941 operator++() was used for both, so we allow this with
4943 if (flags & LOOKUP_COMPLAIN)
4945 const char *msg = (flag_permissive)
4946 ? G_("no %<%D(int)%> declared for postfix %qs,"
4947 " trying prefix operator instead")
4948 : G_("no %<%D(int)%> declared for postfix %qs");
4949 permerror (input_location, msg, fnname,
4950 operator_name_info[code].name);
4953 if (!flag_permissive)
4954 return error_mark_node;
4956 if (code == POSTINCREMENT_EXPR)
4957 code = PREINCREMENT_EXPR;
4959 code = PREDECREMENT_EXPR;
4960 result = build_new_op_1 (code, flags, arg1, NULL_TREE, NULL_TREE,
4961 overload, complain);
4964 /* The caller will deal with these. */
4969 result_valid_p = true;
4973 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
4975 /* If one of the arguments of the operator represents
4976 an invalid use of member function pointer, try to report
4977 a meaningful error ... */
4978 if (invalid_nonstatic_memfn_p (arg1, tf_error)
4979 || invalid_nonstatic_memfn_p (arg2, tf_error)
4980 || invalid_nonstatic_memfn_p (arg3, tf_error))
4981 /* We displayed the error message. */;
4984 /* ... Otherwise, report the more generic
4985 "no matching operator found" error */
4986 op_error (code, code2, arg1, arg2, arg3, FALSE);
4987 print_z_candidates (input_location, candidates);
4990 result = error_mark_node;
4996 cand = tourney (candidates);
4999 if ((flags & LOOKUP_COMPLAIN) && (complain & tf_error))
5001 op_error (code, code2, arg1, arg2, arg3, TRUE);
5002 print_z_candidates (input_location, candidates);
5004 result = error_mark_node;
5006 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
5009 *overload = cand->fn;
5011 if (resolve_args (arglist, complain) == NULL)
5012 result = error_mark_node;
5014 result = build_over_call (cand, LOOKUP_NORMAL, complain);
5018 /* Give any warnings we noticed during overload resolution. */
5019 if (cand->warnings && (complain & tf_warning))
5021 struct candidate_warning *w;
5022 for (w = cand->warnings; w; w = w->next)
5023 joust (cand, w->loser, 1);
5026 /* Check for comparison of different enum types. */
5035 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
5036 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
5037 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
5038 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
5039 && (complain & tf_warning))
5041 warning (OPT_Wenum_compare,
5042 "comparison between %q#T and %q#T",
5043 TREE_TYPE (arg1), TREE_TYPE (arg2));
5050 /* We need to strip any leading REF_BIND so that bitfields
5051 don't cause errors. This should not remove any important
5052 conversions, because builtins don't apply to class
5053 objects directly. */
5054 conv = cand->convs[0];
5055 if (conv->kind == ck_ref_bind)
5056 conv = conv->u.next;
5057 arg1 = convert_like (conv, arg1, complain);
5061 /* We need to call warn_logical_operator before
5062 converting arg2 to a boolean_type. */
5063 if (complain & tf_warning)
5064 warn_logical_operator (input_location, code, boolean_type_node,
5065 code_orig_arg1, arg1,
5066 code_orig_arg2, arg2);
5068 conv = cand->convs[1];
5069 if (conv->kind == ck_ref_bind)
5070 conv = conv->u.next;
5071 arg2 = convert_like (conv, arg2, complain);
5075 conv = cand->convs[2];
5076 if (conv->kind == ck_ref_bind)
5077 conv = conv->u.next;
5078 arg3 = convert_like (conv, arg3, complain);
5084 user_defined_result_ready:
5086 /* Free all the conversions we allocated. */
5087 obstack_free (&conversion_obstack, p);
5089 if (result || result_valid_p)
5093 avoid_sign_compare_warnings (orig_arg1, arg1);
5094 avoid_sign_compare_warnings (orig_arg2, arg2);
5095 avoid_sign_compare_warnings (orig_arg3, arg3);
5100 return cp_build_modify_expr (arg1, code2, arg2, complain);
5103 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
5105 case TRUTH_ANDIF_EXPR:
5106 case TRUTH_ORIF_EXPR:
5107 case TRUTH_AND_EXPR:
5109 warn_logical_operator (input_location, code, boolean_type_node,
5110 code_orig_arg1, arg1, code_orig_arg2, arg2);
5115 case TRUNC_DIV_EXPR:
5126 case TRUNC_MOD_EXPR:
5130 return cp_build_binary_op (input_location, code, arg1, arg2, complain);
5132 case UNARY_PLUS_EXPR:
5135 case TRUTH_NOT_EXPR:
5136 case PREINCREMENT_EXPR:
5137 case POSTINCREMENT_EXPR:
5138 case PREDECREMENT_EXPR:
5139 case POSTDECREMENT_EXPR:
5142 return cp_build_unary_op (code, arg1, candidates != 0, complain);
5145 return cp_build_array_ref (input_location, arg1, arg2, complain);
5148 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_NULL,
5152 /* The caller will deal with these. */
5164 /* Wrapper for above. */
5167 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
5168 tree *overload, tsubst_flags_t complain)
5171 bool subtime = timevar_cond_start (TV_OVERLOAD);
5172 ret = build_new_op_1 (code, flags, arg1, arg2, arg3, overload, complain);
5173 timevar_cond_stop (TV_OVERLOAD, subtime);
5177 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5178 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5181 non_placement_deallocation_fn_p (tree t)
5183 /* A template instance is never a usual deallocation function,
5184 regardless of its signature. */
5185 if (TREE_CODE (t) == TEMPLATE_DECL
5186 || primary_template_instantiation_p (t))
5189 /* If a class T has a member deallocation function named operator delete
5190 with exactly one parameter, then that function is a usual
5191 (non-placement) deallocation function. If class T does not declare
5192 such an operator delete but does declare a member deallocation
5193 function named operator delete with exactly two parameters, the second
5194 of which has type std::size_t (18.2), then this function is a usual
5195 deallocation function. */
5196 t = FUNCTION_ARG_CHAIN (t);
5197 if (t == void_list_node
5198 || (t && same_type_p (TREE_VALUE (t), size_type_node)
5199 && TREE_CHAIN (t) == void_list_node))
5204 /* Build a call to operator delete. This has to be handled very specially,
5205 because the restrictions on what signatures match are different from all
5206 other call instances. For a normal delete, only a delete taking (void *)
5207 or (void *, size_t) is accepted. For a placement delete, only an exact
5208 match with the placement new is accepted.
5210 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5211 ADDR is the pointer to be deleted.
5212 SIZE is the size of the memory block to be deleted.
5213 GLOBAL_P is true if the delete-expression should not consider
5214 class-specific delete operators.
5215 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5217 If this call to "operator delete" is being generated as part to
5218 deallocate memory allocated via a new-expression (as per [expr.new]
5219 which requires that if the initialization throws an exception then
5220 we call a deallocation function), then ALLOC_FN is the allocation
5224 build_op_delete_call (enum tree_code code, tree addr, tree size,
5225 bool global_p, tree placement,
5228 tree fn = NULL_TREE;
5229 tree fns, fnname, type, t;
5231 if (addr == error_mark_node)
5232 return error_mark_node;
5234 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
5236 fnname = ansi_opname (code);
5238 if (CLASS_TYPE_P (type)
5239 && COMPLETE_TYPE_P (complete_type (type))
5243 If the result of the lookup is ambiguous or inaccessible, or if
5244 the lookup selects a placement deallocation function, the
5245 program is ill-formed.
5247 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5249 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
5250 if (fns == error_mark_node)
5251 return error_mark_node;
5256 if (fns == NULL_TREE)
5257 fns = lookup_name_nonclass (fnname);
5259 /* Strip const and volatile from addr. */
5260 addr = cp_convert (ptr_type_node, addr);
5264 /* "A declaration of a placement deallocation function matches the
5265 declaration of a placement allocation function if it has the same
5266 number of parameters and, after parameter transformations (8.3.5),
5267 all parameter types except the first are identical."
5269 So we build up the function type we want and ask instantiate_type
5270 to get it for us. */
5271 t = FUNCTION_ARG_CHAIN (alloc_fn);
5272 t = tree_cons (NULL_TREE, ptr_type_node, t);
5273 t = build_function_type (void_type_node, t);
5275 fn = instantiate_type (t, fns, tf_none);
5276 if (fn == error_mark_node)
5279 if (BASELINK_P (fn))
5280 fn = BASELINK_FUNCTIONS (fn);
5282 /* "If the lookup finds the two-parameter form of a usual deallocation
5283 function (3.7.4.2) and that function, considered as a placement
5284 deallocation function, would have been selected as a match for the
5285 allocation function, the program is ill-formed." */
5286 if (non_placement_deallocation_fn_p (fn))
5288 /* But if the class has an operator delete (void *), then that is
5289 the usual deallocation function, so we shouldn't complain
5290 about using the operator delete (void *, size_t). */
5291 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5292 t; t = OVL_NEXT (t))
5294 tree elt = OVL_CURRENT (t);
5295 if (non_placement_deallocation_fn_p (elt)
5296 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
5299 permerror (0, "non-placement deallocation function %q+D", fn);
5300 permerror (input_location, "selected for placement delete");
5305 /* "Any non-placement deallocation function matches a non-placement
5306 allocation function. If the lookup finds a single matching
5307 deallocation function, that function will be called; otherwise, no
5308 deallocation function will be called." */
5309 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5310 t; t = OVL_NEXT (t))
5312 tree elt = OVL_CURRENT (t);
5313 if (non_placement_deallocation_fn_p (elt))
5316 /* "If a class T has a member deallocation function named
5317 operator delete with exactly one parameter, then that
5318 function is a usual (non-placement) deallocation
5319 function. If class T does not declare such an operator
5320 delete but does declare a member deallocation function named
5321 operator delete with exactly two parameters, the second of
5322 which has type std::size_t (18.2), then this function is a
5323 usual deallocation function."
5325 So (void*) beats (void*, size_t). */
5326 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
5331 /* If we have a matching function, call it. */
5334 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5336 /* If the FN is a member function, make sure that it is
5338 if (BASELINK_P (fns))
5339 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn);
5341 /* Core issue 901: It's ok to new a type with deleted delete. */
5342 if (DECL_DELETED_FN (fn) && alloc_fn)
5347 /* The placement args might not be suitable for overload
5348 resolution at this point, so build the call directly. */
5349 int nargs = call_expr_nargs (placement);
5350 tree *argarray = XALLOCAVEC (tree, nargs);
5353 for (i = 1; i < nargs; i++)
5354 argarray[i] = CALL_EXPR_ARG (placement, i);
5356 return build_cxx_call (fn, nargs, argarray);
5361 VEC(tree,gc) *args = VEC_alloc (tree, gc, 2);
5362 VEC_quick_push (tree, args, addr);
5363 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
5364 VEC_quick_push (tree, args, size);
5365 ret = cp_build_function_call_vec (fn, &args, tf_warning_or_error);
5366 VEC_free (tree, gc, args);
5373 If no unambiguous matching deallocation function can be found,
5374 propagating the exception does not cause the object's memory to
5379 warning (0, "no corresponding deallocation function for %qD",
5384 error ("no suitable %<operator %s%> for %qT",
5385 operator_name_info[(int)code].name, type);
5386 return error_mark_node;
5389 /* If the current scope isn't allowed to access DECL along
5390 BASETYPE_PATH, give an error. The most derived class in
5391 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
5392 the declaration to use in the error diagnostic. */
5395 enforce_access (tree basetype_path, tree decl, tree diag_decl)
5397 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
5399 if (!accessible_p (basetype_path, decl, true))
5401 if (TREE_PRIVATE (decl))
5402 error ("%q+#D is private", diag_decl);
5403 else if (TREE_PROTECTED (decl))
5404 error ("%q+#D is protected", diag_decl);
5406 error ("%q+#D is inaccessible", diag_decl);
5407 error ("within this context");
5414 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
5415 bitwise or of LOOKUP_* values. If any errors are warnings are
5416 generated, set *DIAGNOSTIC_FN to "error" or "warning",
5417 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
5421 build_temp (tree expr, tree type, int flags,
5422 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
5427 savew = warningcount, savee = errorcount;
5428 args = make_tree_vector_single (expr);
5429 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
5430 &args, type, flags, complain);
5431 release_tree_vector (args);
5432 if (warningcount > savew)
5433 *diagnostic_kind = DK_WARNING;
5434 else if (errorcount > savee)
5435 *diagnostic_kind = DK_ERROR;
5437 *diagnostic_kind = DK_UNSPECIFIED;
5441 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
5442 EXPR is implicitly converted to type TOTYPE.
5443 FN and ARGNUM are used for diagnostics. */
5446 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
5448 tree t = non_reference (totype);
5450 /* Issue warnings about peculiar, but valid, uses of NULL. */
5451 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
5454 warning_at (input_location, OPT_Wconversion_null,
5455 "passing NULL to non-pointer argument %P of %qD",
5458 warning_at (input_location, OPT_Wconversion_null,
5459 "converting to non-pointer type %qT from NULL", t);
5462 /* Issue warnings if "false" is converted to a NULL pointer */
5463 else if (expr == boolean_false_node && POINTER_TYPE_P (t))
5466 warning_at (input_location, OPT_Wconversion_null,
5467 "converting %<false%> to pointer type for argument %P "
5468 "of %qD", argnum, fn);
5470 warning_at (input_location, OPT_Wconversion_null,
5471 "converting %<false%> to pointer type %qT", t);
5475 /* Perform the conversions in CONVS on the expression EXPR. FN and
5476 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
5477 indicates the `this' argument of a method. INNER is nonzero when
5478 being called to continue a conversion chain. It is negative when a
5479 reference binding will be applied, positive otherwise. If
5480 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
5481 conversions will be emitted if appropriate. If C_CAST_P is true,
5482 this conversion is coming from a C-style cast; in that case,
5483 conversions to inaccessible bases are permitted. */
5486 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
5487 int inner, bool issue_conversion_warnings,
5488 bool c_cast_p, tsubst_flags_t complain)
5490 tree totype = convs->type;
5491 diagnostic_t diag_kind;
5495 && convs->kind != ck_user
5496 && convs->kind != ck_list
5497 && convs->kind != ck_ambig
5498 && convs->kind != ck_ref_bind
5499 && convs->kind != ck_rvalue
5500 && convs->kind != ck_base)
5502 conversion *t = convs;
5504 /* Give a helpful error if this is bad because of excess braces. */
5505 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
5506 && SCALAR_TYPE_P (totype)
5507 && CONSTRUCTOR_NELTS (expr) > 0
5508 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
5509 permerror (input_location, "too many braces around initializer for %qT", totype);
5511 for (; t; t = convs->u.next)
5513 if (t->kind == ck_user || !t->bad_p)
5515 expr = convert_like_real (t, expr, fn, argnum, 1,
5516 /*issue_conversion_warnings=*/false,
5521 else if (t->kind == ck_ambig)
5522 return convert_like_real (t, expr, fn, argnum, 1,
5523 /*issue_conversion_warnings=*/false,
5526 else if (t->kind == ck_identity)
5529 if (complain & tf_error)
5531 permerror (input_location, "invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
5533 permerror (DECL_SOURCE_LOCATION (fn),
5534 " initializing argument %P of %qD", argnum, fn);
5537 return error_mark_node;
5539 return cp_convert (totype, expr);
5542 if (issue_conversion_warnings && (complain & tf_warning))
5543 conversion_null_warnings (totype, expr, fn, argnum);
5545 switch (convs->kind)
5549 struct z_candidate *cand = convs->cand;
5550 tree convfn = cand->fn;
5553 expr = mark_rvalue_use (expr);
5555 /* When converting from an init list we consider explicit
5556 constructors, but actually trying to call one is an error. */
5557 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
5558 /* Unless we're calling it for value-initialization from an
5559 empty list, since that is handled separately in 8.5.4. */
5560 && cand->num_convs > 0)
5562 if (complain & tf_error)
5563 error ("converting to %qT from initializer list would use "
5564 "explicit constructor %qD", totype, convfn);
5566 return error_mark_node;
5569 /* Set user_conv_p on the argument conversions, so rvalue/base
5570 handling knows not to allow any more UDCs. */
5571 for (i = 0; i < cand->num_convs; ++i)
5572 cand->convs[i]->user_conv_p = true;
5574 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
5576 /* If this is a constructor or a function returning an aggr type,
5577 we need to build up a TARGET_EXPR. */
5578 if (DECL_CONSTRUCTOR_P (convfn))
5580 expr = build_cplus_new (totype, expr, complain);
5582 /* Remember that this was list-initialization. */
5583 if (convs->check_narrowing)
5584 TARGET_EXPR_LIST_INIT_P (expr) = true;
5590 expr = mark_rvalue_use (expr);
5591 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
5593 int nelts = CONSTRUCTOR_NELTS (expr);
5595 expr = build_value_init (totype, tf_warning_or_error);
5596 else if (nelts == 1)
5597 expr = CONSTRUCTOR_ELT (expr, 0)->value;
5602 if (type_unknown_p (expr))
5603 expr = instantiate_type (totype, expr, complain);
5604 /* Convert a constant to its underlying value, unless we are
5605 about to bind it to a reference, in which case we need to
5606 leave it as an lvalue. */
5609 expr = decl_constant_value (expr);
5610 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
5611 /* If __null has been converted to an integer type, we do not
5612 want to warn about uses of EXPR as an integer, rather than
5614 expr = build_int_cst (totype, 0);
5618 if (complain & tf_error)
5620 /* Call build_user_type_conversion again for the error. */
5621 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL);
5623 error (" initializing argument %P of %q+D", argnum, fn);
5625 return error_mark_node;
5629 /* Conversion to std::initializer_list<T>. */
5630 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
5631 tree new_ctor = build_constructor (init_list_type_node, NULL);
5632 unsigned len = CONSTRUCTOR_NELTS (expr);
5633 tree array, val, field;
5634 VEC(constructor_elt,gc) *vec = NULL;
5637 /* Convert all the elements. */
5638 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
5640 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
5641 1, false, false, complain);
5642 if (sub == error_mark_node)
5644 if (!BRACE_ENCLOSED_INITIALIZER_P (val))
5645 check_narrowing (TREE_TYPE (sub), val);
5646 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
5647 if (!TREE_CONSTANT (sub))
5648 TREE_CONSTANT (new_ctor) = false;
5650 /* Build up the array. */
5651 elttype = cp_build_qualified_type
5652 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
5653 array = build_array_of_n_type (elttype, len);
5654 array = finish_compound_literal (array, new_ctor, complain);
5656 /* Build up the initializer_list object. */
5657 totype = complete_type (totype);
5658 field = next_initializable_field (TYPE_FIELDS (totype));
5659 CONSTRUCTOR_APPEND_ELT (vec, field, decay_conversion (array));
5660 field = next_initializable_field (DECL_CHAIN (field));
5661 CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len));
5662 new_ctor = build_constructor (totype, vec);
5663 return get_target_expr (new_ctor);
5667 if (TREE_CODE (totype) == COMPLEX_TYPE)
5669 tree real = CONSTRUCTOR_ELT (expr, 0)->value;
5670 tree imag = CONSTRUCTOR_ELT (expr, 1)->value;
5671 real = perform_implicit_conversion (TREE_TYPE (totype),
5673 imag = perform_implicit_conversion (TREE_TYPE (totype),
5675 expr = build2 (COMPLEX_EXPR, totype, real, imag);
5676 return fold_if_not_in_template (expr);
5678 return get_target_expr (digest_init (totype, expr, complain));
5684 expr = convert_like_real (convs->u.next, expr, fn, argnum,
5685 convs->kind == ck_ref_bind ? -1 : 1,
5686 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
5689 if (expr == error_mark_node)
5690 return error_mark_node;
5692 switch (convs->kind)
5695 expr = decay_conversion (expr);
5696 if (! MAYBE_CLASS_TYPE_P (totype))
5698 /* Else fall through. */
5700 if (convs->kind == ck_base && !convs->need_temporary_p)
5702 /* We are going to bind a reference directly to a base-class
5703 subobject of EXPR. */
5704 /* Build an expression for `*((base*) &expr)'. */
5705 expr = cp_build_addr_expr (expr, complain);
5706 expr = convert_to_base (expr, build_pointer_type (totype),
5707 !c_cast_p, /*nonnull=*/true, complain);
5708 expr = cp_build_indirect_ref (expr, RO_IMPLICIT_CONVERSION, complain);
5712 /* Copy-initialization where the cv-unqualified version of the source
5713 type is the same class as, or a derived class of, the class of the
5714 destination [is treated as direct-initialization]. [dcl.init] */
5715 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
5716 if (convs->user_conv_p)
5717 /* This conversion is being done in the context of a user-defined
5718 conversion (i.e. the second step of copy-initialization), so
5719 don't allow any more. */
5720 flags |= LOOKUP_NO_CONVERSION;
5721 if (convs->rvaluedness_matches_p)
5722 flags |= LOOKUP_PREFER_RVALUE;
5723 if (TREE_CODE (expr) == TARGET_EXPR
5724 && TARGET_EXPR_LIST_INIT_P (expr))
5725 /* Copy-list-initialization doesn't actually involve a copy. */
5727 expr = build_temp (expr, totype, flags, &diag_kind, complain);
5728 if (diag_kind && fn)
5730 if ((complain & tf_error))
5731 emit_diagnostic (diag_kind, DECL_SOURCE_LOCATION (fn), 0,
5732 " initializing argument %P of %qD", argnum, fn);
5733 else if (diag_kind == DK_ERROR)
5734 return error_mark_node;
5736 return build_cplus_new (totype, expr, complain);
5740 tree ref_type = totype;
5742 if (convs->bad_p && TYPE_REF_IS_RVALUE (ref_type)
5743 && real_lvalue_p (expr))
5745 if (complain & tf_error)
5747 error ("cannot bind %qT lvalue to %qT",
5748 TREE_TYPE (expr), totype);
5750 error (" initializing argument %P of %q+D", argnum, fn);
5752 return error_mark_node;
5755 /* If necessary, create a temporary.
5757 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5758 that need temporaries, even when their types are reference
5759 compatible with the type of reference being bound, so the
5760 upcoming call to cp_build_addr_expr doesn't fail. */
5761 if (convs->need_temporary_p
5762 || TREE_CODE (expr) == CONSTRUCTOR
5763 || TREE_CODE (expr) == VA_ARG_EXPR)
5765 /* Otherwise, a temporary of type "cv1 T1" is created and
5766 initialized from the initializer expression using the rules
5767 for a non-reference copy-initialization (8.5). */
5769 tree type = TREE_TYPE (ref_type);
5770 cp_lvalue_kind lvalue = real_lvalue_p (expr);
5772 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5773 (type, convs->u.next->type));
5774 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
5775 && !TYPE_REF_IS_RVALUE (ref_type))
5777 if (complain & tf_error)
5779 /* If the reference is volatile or non-const, we
5780 cannot create a temporary. */
5781 if (lvalue & clk_bitfield)
5782 error ("cannot bind bitfield %qE to %qT",
5784 else if (lvalue & clk_packed)
5785 error ("cannot bind packed field %qE to %qT",
5788 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
5790 return error_mark_node;
5792 /* If the source is a packed field, and we must use a copy
5793 constructor, then building the target expr will require
5794 binding the field to the reference parameter to the
5795 copy constructor, and we'll end up with an infinite
5796 loop. If we can use a bitwise copy, then we'll be
5798 if ((lvalue & clk_packed)
5799 && CLASS_TYPE_P (type)
5800 && type_has_nontrivial_copy_init (type))
5802 if (complain & tf_error)
5803 error ("cannot bind packed field %qE to %qT",
5805 return error_mark_node;
5807 if (lvalue & clk_bitfield)
5809 expr = convert_bitfield_to_declared_type (expr);
5810 expr = fold_convert (type, expr);
5812 expr = build_target_expr_with_type (expr, type, complain);
5815 /* Take the address of the thing to which we will bind the
5817 expr = cp_build_addr_expr (expr, complain);
5818 if (expr == error_mark_node)
5819 return error_mark_node;
5821 /* Convert it to a pointer to the type referred to by the
5822 reference. This will adjust the pointer if a derived to
5823 base conversion is being performed. */
5824 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
5826 /* Convert the pointer to the desired reference type. */
5827 return build_nop (ref_type, expr);
5831 return decay_conversion (expr);
5834 /* Warn about deprecated conversion if appropriate. */
5835 string_conv_p (totype, expr, 1);
5840 expr = convert_to_base (expr, totype, !c_cast_p,
5841 /*nonnull=*/false, complain);
5842 return build_nop (totype, expr);
5845 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
5846 c_cast_p, complain);
5852 if (convs->check_narrowing)
5853 check_narrowing (totype, expr);
5855 if (issue_conversion_warnings && (complain & tf_warning))
5856 expr = convert_and_check (totype, expr);
5858 expr = convert (totype, expr);
5863 /* ARG is being passed to a varargs function. Perform any conversions
5864 required. Return the converted value. */
5867 convert_arg_to_ellipsis (tree arg)
5873 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5874 standard conversions are performed. */
5875 arg = decay_conversion (arg);
5876 arg_type = TREE_TYPE (arg);
5879 If the argument has integral or enumeration type that is subject
5880 to the integral promotions (_conv.prom_), or a floating point
5881 type that is subject to the floating point promotion
5882 (_conv.fpprom_), the value of the argument is converted to the
5883 promoted type before the call. */
5884 if (TREE_CODE (arg_type) == REAL_TYPE
5885 && (TYPE_PRECISION (arg_type)
5886 < TYPE_PRECISION (double_type_node))
5887 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
5889 if (warn_double_promotion && !c_inhibit_evaluation_warnings)
5890 warning (OPT_Wdouble_promotion,
5891 "implicit conversion from %qT to %qT when passing "
5892 "argument to function",
5893 arg_type, double_type_node);
5894 arg = convert_to_real (double_type_node, arg);
5896 else if (NULLPTR_TYPE_P (arg_type))
5897 arg = null_pointer_node;
5898 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
5900 if (SCOPED_ENUM_P (arg_type) && !abi_version_at_least (6))
5902 warning (OPT_Wabi, "scoped enum %qT will not promote to an "
5903 "integral type in a future version of GCC", arg_type);
5904 arg = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg);
5906 arg = perform_integral_promotions (arg);
5909 arg = require_complete_type (arg);
5910 arg_type = TREE_TYPE (arg);
5912 if (arg != error_mark_node
5913 /* In a template (or ill-formed code), we can have an incomplete type
5914 even after require_complete_type, in which case we don't know
5915 whether it has trivial copy or not. */
5916 && COMPLETE_TYPE_P (arg_type))
5918 /* Build up a real lvalue-to-rvalue conversion in case the
5919 copy constructor is trivial but not callable. */
5920 if (CLASS_TYPE_P (arg_type))
5921 force_rvalue (arg, tf_warning_or_error);
5923 /* [expr.call] 5.2.2/7:
5924 Passing a potentially-evaluated argument of class type (Clause 9)
5925 with a non-trivial copy constructor or a non-trivial destructor
5926 with no corresponding parameter is conditionally-supported, with
5927 implementation-defined semantics.
5929 We used to just warn here and do a bitwise copy, but now
5930 cp_expr_size will abort if we try to do that.
5932 If the call appears in the context of a sizeof expression,
5933 it is not potentially-evaluated. */
5934 if (cp_unevaluated_operand == 0
5935 && (type_has_nontrivial_copy_init (arg_type)
5936 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
5937 error ("cannot pass objects of non-trivially-copyable "
5938 "type %q#T through %<...%>", arg_type);
5944 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5947 build_x_va_arg (tree expr, tree type)
5949 if (processing_template_decl)
5950 return build_min (VA_ARG_EXPR, type, expr);
5952 type = complete_type_or_else (type, NULL_TREE);
5954 if (expr == error_mark_node || !type)
5955 return error_mark_node;
5957 expr = mark_lvalue_use (expr);
5959 if (type_has_nontrivial_copy_init (type)
5960 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
5961 || TREE_CODE (type) == REFERENCE_TYPE)
5963 /* Remove reference types so we don't ICE later on. */
5964 tree type1 = non_reference (type);
5965 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5966 error ("cannot receive objects of non-trivially-copyable type %q#T "
5967 "through %<...%>; ", type);
5968 expr = convert (build_pointer_type (type1), null_node);
5969 expr = cp_build_indirect_ref (expr, RO_NULL, tf_warning_or_error);
5973 return build_va_arg (input_location, expr, type);
5976 /* TYPE has been given to va_arg. Apply the default conversions which
5977 would have happened when passed via ellipsis. Return the promoted
5978 type, or the passed type if there is no change. */
5981 cxx_type_promotes_to (tree type)
5985 /* Perform the array-to-pointer and function-to-pointer
5987 type = type_decays_to (type);
5989 promote = type_promotes_to (type);
5990 if (same_type_p (type, promote))
5996 /* ARG is a default argument expression being passed to a parameter of
5997 the indicated TYPE, which is a parameter to FN. PARMNUM is the
5998 zero-based argument number. Do any required conversions. Return
5999 the converted value. */
6001 static GTY(()) VEC(tree,gc) *default_arg_context;
6003 push_defarg_context (tree fn)
6004 { VEC_safe_push (tree, gc, default_arg_context, fn); }
6006 pop_defarg_context (void)
6007 { VEC_pop (tree, default_arg_context); }
6010 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
6015 /* See through clones. */
6016 fn = DECL_ORIGIN (fn);
6018 /* Detect recursion. */
6019 FOR_EACH_VEC_ELT (tree, default_arg_context, i, t)
6022 error ("recursive evaluation of default argument for %q#D", fn);
6023 return error_mark_node;
6026 /* If the ARG is an unparsed default argument expression, the
6027 conversion cannot be performed. */
6028 if (TREE_CODE (arg) == DEFAULT_ARG)
6030 error ("call to %qD uses the default argument for parameter %P, which "
6031 "is not yet defined", fn, parmnum);
6032 return error_mark_node;
6035 push_defarg_context (fn);
6037 if (fn && DECL_TEMPLATE_INFO (fn))
6038 arg = tsubst_default_argument (fn, type, arg);
6044 The names in the expression are bound, and the semantic
6045 constraints are checked, at the point where the default
6046 expressions appears.
6048 we must not perform access checks here. */
6049 push_deferring_access_checks (dk_no_check);
6050 arg = break_out_target_exprs (arg);
6051 if (TREE_CODE (arg) == CONSTRUCTOR)
6053 arg = digest_init (type, arg, tf_warning_or_error);
6054 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6055 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6056 tf_warning_or_error);
6060 /* We must make a copy of ARG, in case subsequent processing
6061 alters any part of it. For example, during gimplification a
6062 cast of the form (T) &X::f (where "f" is a member function)
6063 will lead to replacing the PTRMEM_CST for &X::f with a
6064 VAR_DECL. We can avoid the copy for constants, since they
6065 are never modified in place. */
6066 if (!CONSTANT_CLASS_P (arg))
6067 arg = unshare_expr (arg);
6068 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6069 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6070 tf_warning_or_error);
6071 arg = convert_for_arg_passing (type, arg);
6073 pop_deferring_access_checks();
6075 pop_defarg_context ();
6080 /* Returns the type which will really be used for passing an argument of
6084 type_passed_as (tree type)
6086 /* Pass classes with copy ctors by invisible reference. */
6087 if (TREE_ADDRESSABLE (type))
6089 type = build_reference_type (type);
6090 /* There are no other pointers to this temporary. */
6091 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
6093 else if (targetm.calls.promote_prototypes (type)
6094 && INTEGRAL_TYPE_P (type)
6095 && COMPLETE_TYPE_P (type)
6096 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6097 TYPE_SIZE (integer_type_node)))
6098 type = integer_type_node;
6103 /* Actually perform the appropriate conversion. */
6106 convert_for_arg_passing (tree type, tree val)
6110 /* If VAL is a bitfield, then -- since it has already been converted
6111 to TYPE -- it cannot have a precision greater than TYPE.
6113 If it has a smaller precision, we must widen it here. For
6114 example, passing "int f:3;" to a function expecting an "int" will
6115 not result in any conversion before this point.
6117 If the precision is the same we must not risk widening. For
6118 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6119 often have type "int", even though the C++ type for the field is
6120 "long long". If the value is being passed to a function
6121 expecting an "int", then no conversions will be required. But,
6122 if we call convert_bitfield_to_declared_type, the bitfield will
6123 be converted to "long long". */
6124 bitfield_type = is_bitfield_expr_with_lowered_type (val);
6126 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
6127 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
6129 if (val == error_mark_node)
6131 /* Pass classes with copy ctors by invisible reference. */
6132 else if (TREE_ADDRESSABLE (type))
6133 val = build1 (ADDR_EXPR, build_reference_type (type), val);
6134 else if (targetm.calls.promote_prototypes (type)
6135 && INTEGRAL_TYPE_P (type)
6136 && COMPLETE_TYPE_P (type)
6137 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
6138 TYPE_SIZE (integer_type_node)))
6139 val = perform_integral_promotions (val);
6140 if (warn_missing_format_attribute)
6142 tree rhstype = TREE_TYPE (val);
6143 const enum tree_code coder = TREE_CODE (rhstype);
6144 const enum tree_code codel = TREE_CODE (type);
6145 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6147 && check_missing_format_attribute (type, rhstype))
6148 warning (OPT_Wmissing_format_attribute,
6149 "argument of function call might be a candidate for a format attribute");
6154 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6155 which no conversions at all should be done. This is true for some
6156 builtins which don't act like normal functions. */
6159 magic_varargs_p (tree fn)
6161 if (DECL_BUILT_IN (fn))
6162 switch (DECL_FUNCTION_CODE (fn))
6164 case BUILT_IN_CLASSIFY_TYPE:
6165 case BUILT_IN_CONSTANT_P:
6166 case BUILT_IN_NEXT_ARG:
6167 case BUILT_IN_VA_START:
6171 return lookup_attribute ("type generic",
6172 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
6178 /* Subroutine of the various build_*_call functions. Overload resolution
6179 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
6180 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
6181 bitmask of various LOOKUP_* flags which apply to the call itself. */
6184 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
6187 const VEC(tree,gc) *args = cand->args;
6188 tree first_arg = cand->first_arg;
6189 conversion **convs = cand->convs;
6191 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
6196 unsigned int arg_index = 0;
6200 bool already_used = false;
6202 /* In a template, there is no need to perform all of the work that
6203 is normally done. We are only interested in the type of the call
6204 expression, i.e., the return type of the function. Any semantic
6205 errors will be deferred until the template is instantiated. */
6206 if (processing_template_decl)
6210 const tree *argarray;
6213 return_type = TREE_TYPE (TREE_TYPE (fn));
6214 nargs = VEC_length (tree, args);
6215 if (first_arg == NULL_TREE)
6216 argarray = VEC_address (tree, CONST_CAST (VEC(tree,gc) *, args));
6224 alcarray = XALLOCAVEC (tree, nargs);
6225 alcarray[0] = first_arg;
6226 FOR_EACH_VEC_ELT (tree, args, ix, arg)
6227 alcarray[ix + 1] = arg;
6228 argarray = alcarray;
6230 expr = build_call_array_loc (input_location,
6231 return_type, build_addr_func (fn), nargs,
6233 if (TREE_THIS_VOLATILE (fn) && cfun)
6234 current_function_returns_abnormally = 1;
6235 return convert_from_reference (expr);
6238 /* Give any warnings we noticed during overload resolution. */
6239 if (cand->warnings && (complain & tf_warning))
6241 struct candidate_warning *w;
6242 for (w = cand->warnings; w; w = w->next)
6243 joust (cand, w->loser, 1);
6246 /* Make =delete work with SFINAE. */
6247 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
6248 return error_mark_node;
6250 if (DECL_FUNCTION_MEMBER_P (fn))
6253 /* If FN is a template function, two cases must be considered.
6258 template <class T> void f();
6260 template <class T> struct B {
6264 struct C : A, B<int> {
6266 using B<int>::g; // #2
6269 In case #1 where `A::f' is a member template, DECL_ACCESS is
6270 recorded in the primary template but not in its specialization.
6271 We check access of FN using its primary template.
6273 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
6274 because it is a member of class template B, DECL_ACCESS is
6275 recorded in the specialization `B<int>::g'. We cannot use its
6276 primary template because `B<T>::g' and `B<int>::g' may have
6277 different access. */
6278 if (DECL_TEMPLATE_INFO (fn)
6279 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
6280 access_fn = DECL_TI_TEMPLATE (fn);
6283 if (flags & LOOKUP_SPECULATIVE)
6285 if (!speculative_access_check (cand->access_path, access_fn, fn,
6286 !!(flags & LOOKUP_COMPLAIN)))
6287 return error_mark_node;
6290 perform_or_defer_access_check (cand->access_path, access_fn, fn);
6293 /* If we're checking for implicit delete, don't bother with argument
6295 if (flags & LOOKUP_SPECULATIVE)
6297 if (DECL_DELETED_FN (fn))
6299 if (flags & LOOKUP_COMPLAIN)
6301 return error_mark_node;
6303 if (cand->viable == 1)
6305 else if (!(flags & LOOKUP_COMPLAIN))
6306 /* Reject bad conversions now. */
6307 return error_mark_node;
6308 /* else continue to get conversion error. */
6311 /* Find maximum size of vector to hold converted arguments. */
6312 parmlen = list_length (parm);
6313 nargs = VEC_length (tree, args) + (first_arg != NULL_TREE ? 1 : 0);
6314 if (parmlen > nargs)
6316 argarray = XALLOCAVEC (tree, nargs);
6318 /* The implicit parameters to a constructor are not considered by overload
6319 resolution, and must be of the proper type. */
6320 if (DECL_CONSTRUCTOR_P (fn))
6322 if (first_arg != NULL_TREE)
6324 argarray[j++] = first_arg;
6325 first_arg = NULL_TREE;
6329 argarray[j++] = VEC_index (tree, args, arg_index);
6332 parm = TREE_CHAIN (parm);
6333 /* We should never try to call the abstract constructor. */
6334 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
6336 if (DECL_HAS_VTT_PARM_P (fn))
6338 argarray[j++] = VEC_index (tree, args, arg_index);
6340 parm = TREE_CHAIN (parm);
6343 /* Bypass access control for 'this' parameter. */
6344 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
6346 tree parmtype = TREE_VALUE (parm);
6347 tree arg = (first_arg != NULL_TREE
6349 : VEC_index (tree, args, arg_index));
6350 tree argtype = TREE_TYPE (arg);
6354 if (convs[i]->bad_p)
6356 if (complain & tf_error)
6357 permerror (input_location, "passing %qT as %<this%> argument of %q#D discards qualifiers",
6358 TREE_TYPE (argtype), fn);
6360 return error_mark_node;
6363 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
6364 X is called for an object that is not of type X, or of a type
6365 derived from X, the behavior is undefined.
6367 So we can assume that anything passed as 'this' is non-null, and
6368 optimize accordingly. */
6369 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
6370 /* Convert to the base in which the function was declared. */
6371 gcc_assert (cand->conversion_path != NULL_TREE);
6372 converted_arg = build_base_path (PLUS_EXPR,
6374 cand->conversion_path,
6376 /* Check that the base class is accessible. */
6377 if (!accessible_base_p (TREE_TYPE (argtype),
6378 BINFO_TYPE (cand->conversion_path), true))
6379 error ("%qT is not an accessible base of %qT",
6380 BINFO_TYPE (cand->conversion_path),
6381 TREE_TYPE (argtype));
6382 /* If fn was found by a using declaration, the conversion path
6383 will be to the derived class, not the base declaring fn. We
6384 must convert from derived to base. */
6385 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
6386 TREE_TYPE (parmtype), ba_unique, NULL);
6387 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
6390 argarray[j++] = converted_arg;
6391 parm = TREE_CHAIN (parm);
6392 if (first_arg != NULL_TREE)
6393 first_arg = NULL_TREE;
6400 gcc_assert (first_arg == NULL_TREE);
6401 for (; arg_index < VEC_length (tree, args) && parm;
6402 parm = TREE_CHAIN (parm), ++arg_index, ++i)
6404 tree type = TREE_VALUE (parm);
6405 tree arg = VEC_index (tree, args, arg_index);
6406 bool conversion_warning = true;
6410 /* If the argument is NULL and used to (implicitly) instantiate a
6411 template function (and bind one of the template arguments to
6412 the type of 'long int'), we don't want to warn about passing NULL
6413 to non-pointer argument.
6414 For example, if we have this template function:
6416 template<typename T> void func(T x) {}
6418 we want to warn (when -Wconversion is enabled) in this case:
6424 but not in this case:
6430 if (arg == null_node
6431 && DECL_TEMPLATE_INFO (fn)
6432 && cand->template_decl
6433 && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS))
6434 conversion_warning = false;
6436 /* Warn about initializer_list deduction that isn't currently in the
6438 if (cxx_dialect > cxx98
6439 && flag_deduce_init_list
6440 && cand->template_decl
6441 && is_std_init_list (non_reference (type))
6442 && BRACE_ENCLOSED_INITIALIZER_P (arg))
6444 tree tmpl = TI_TEMPLATE (cand->template_decl);
6445 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
6446 tree patparm = get_pattern_parm (realparm, tmpl);
6447 tree pattype = TREE_TYPE (patparm);
6448 if (PACK_EXPANSION_P (pattype))
6449 pattype = PACK_EXPANSION_PATTERN (pattype);
6450 pattype = non_reference (pattype);
6452 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
6453 && (cand->explicit_targs == NULL_TREE
6454 || (TREE_VEC_LENGTH (cand->explicit_targs)
6455 <= TEMPLATE_TYPE_IDX (pattype))))
6457 pedwarn (input_location, 0, "deducing %qT as %qT",
6458 non_reference (TREE_TYPE (patparm)),
6459 non_reference (type));
6460 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
6461 pedwarn (input_location, 0,
6462 " (you can disable this with -fno-deduce-init-list)");
6466 val = convert_like_with_context (conv, arg, fn, i-is_method,
6469 : complain & (~tf_warning));
6471 val = convert_for_arg_passing (type, val);
6472 if (val == error_mark_node)
6473 return error_mark_node;
6475 argarray[j++] = val;
6478 /* Default arguments */
6479 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
6480 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
6481 TREE_PURPOSE (parm),
6484 for (; arg_index < VEC_length (tree, args); ++arg_index)
6486 tree a = VEC_index (tree, args, arg_index);
6487 if (magic_varargs_p (fn))
6488 /* Do no conversions for magic varargs. */
6489 a = mark_type_use (a);
6491 a = convert_arg_to_ellipsis (a);
6495 gcc_assert (j <= nargs);
6498 check_function_arguments (TREE_TYPE (fn), nargs, argarray);
6500 /* Avoid actually calling copy constructors and copy assignment operators,
6503 if (! flag_elide_constructors)
6504 /* Do things the hard way. */;
6505 else if (cand->num_convs == 1
6506 && (DECL_COPY_CONSTRUCTOR_P (fn)
6507 || DECL_MOVE_CONSTRUCTOR_P (fn)))
6510 tree arg = argarray[num_artificial_parms_for (fn)];
6512 bool trivial = trivial_fn_p (fn);
6514 /* Pull out the real argument, disregarding const-correctness. */
6516 while (CONVERT_EXPR_P (targ)
6517 || TREE_CODE (targ) == NON_LVALUE_EXPR)
6518 targ = TREE_OPERAND (targ, 0);
6519 if (TREE_CODE (targ) == ADDR_EXPR)
6521 targ = TREE_OPERAND (targ, 0);
6522 if (!same_type_ignoring_top_level_qualifiers_p
6523 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
6532 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6534 /* [class.copy]: the copy constructor is implicitly defined even if
6535 the implementation elided its use. */
6536 if (!trivial || DECL_DELETED_FN (fn))
6539 already_used = true;
6542 /* If we're creating a temp and we already have one, don't create a
6543 new one. If we're not creating a temp but we get one, use
6544 INIT_EXPR to collapse the temp into our target. Otherwise, if the
6545 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
6546 temp or an INIT_EXPR otherwise. */
6548 if (integer_zerop (fa))
6550 if (TREE_CODE (arg) == TARGET_EXPR)
6553 return force_target_expr (DECL_CONTEXT (fn), arg, complain);
6555 else if (TREE_CODE (arg) == TARGET_EXPR || trivial)
6557 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
6560 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
6564 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
6565 && trivial_fn_p (fn)
6566 && !DECL_DELETED_FN (fn))
6568 tree to = stabilize_reference
6569 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
6570 tree type = TREE_TYPE (to);
6571 tree as_base = CLASSTYPE_AS_BASE (type);
6572 tree arg = argarray[1];
6574 if (is_really_empty_class (type))
6576 /* Avoid copying empty classes. */
6577 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
6578 TREE_NO_WARNING (val) = 1;
6579 val = build2 (COMPOUND_EXPR, type, val, to);
6580 TREE_NO_WARNING (val) = 1;
6582 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
6584 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
6585 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
6589 /* We must only copy the non-tail padding parts.
6590 Use __builtin_memcpy for the bitwise copy.
6591 FIXME fix 22488 so we can go back to using MODIFY_EXPR
6592 instead of an explicit call to memcpy. */
6594 tree arg0, arg1, arg2, t;
6595 tree test = NULL_TREE;
6597 arg2 = TYPE_SIZE_UNIT (as_base);
6599 arg0 = cp_build_addr_expr (to, complain);
6601 if (!can_trust_pointer_alignment ())
6603 /* If we can't be sure about pointer alignment, a call
6604 to __builtin_memcpy is expanded as a call to memcpy, which
6605 is invalid with identical args. Otherwise it is
6606 expanded as a block move, which should be safe. */
6607 arg0 = save_expr (arg0);
6608 arg1 = save_expr (arg1);
6609 test = build2 (EQ_EXPR, boolean_type_node, arg0, arg1);
6611 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
6612 t = build_call_n (t, 3, arg0, arg1, arg2);
6614 t = convert (TREE_TYPE (arg0), t);
6616 t = build3 (COND_EXPR, TREE_TYPE (t), test, arg0, t);
6617 val = cp_build_indirect_ref (t, RO_NULL, complain);
6618 TREE_NO_WARNING (val) = 1;
6623 else if (DECL_DESTRUCTOR_P (fn)
6624 && trivial_fn_p (fn)
6625 && !DECL_DELETED_FN (fn))
6626 return fold_convert (void_type_node, argarray[0]);
6627 /* FIXME handle trivial default constructor, too. */
6632 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
6635 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
6638 gcc_assert (binfo && binfo != error_mark_node);
6640 /* Warn about deprecated virtual functions now, since we're about
6641 to throw away the decl. */
6642 if (TREE_DEPRECATED (fn))
6643 warn_deprecated_use (fn, NULL_TREE);
6645 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
6646 if (TREE_SIDE_EFFECTS (argarray[0]))
6647 argarray[0] = save_expr (argarray[0]);
6648 t = build_pointer_type (TREE_TYPE (fn));
6649 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
6650 fn = build_java_interface_fn_ref (fn, argarray[0]);
6652 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
6656 fn = build_addr_func (fn);
6658 return build_cxx_call (fn, nargs, argarray);
6661 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
6662 This function performs no overload resolution, conversion, or other
6663 high-level operations. */
6666 build_cxx_call (tree fn, int nargs, tree *argarray)
6670 fn = build_call_a (fn, nargs, argarray);
6672 /* If this call might throw an exception, note that fact. */
6673 fndecl = get_callee_fndecl (fn);
6674 if ((!fndecl || !TREE_NOTHROW (fndecl))
6675 && at_function_scope_p ()
6677 && cp_function_chain)
6678 cp_function_chain->can_throw = 1;
6680 /* Check that arguments to builtin functions match the expectations. */
6682 && DECL_BUILT_IN (fndecl)
6683 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
6684 && !check_builtin_function_arguments (fndecl, nargs, argarray))
6685 return error_mark_node;
6687 /* Some built-in function calls will be evaluated at compile-time in
6689 fn = fold_if_not_in_template (fn);
6691 if (VOID_TYPE_P (TREE_TYPE (fn)))
6694 fn = require_complete_type (fn);
6695 if (fn == error_mark_node)
6696 return error_mark_node;
6698 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
6699 fn = build_cplus_new (TREE_TYPE (fn), fn, tf_warning_or_error);
6700 return convert_from_reference (fn);
6703 static GTY(()) tree java_iface_lookup_fn;
6705 /* Make an expression which yields the address of the Java interface
6706 method FN. This is achieved by generating a call to libjava's
6707 _Jv_LookupInterfaceMethodIdx(). */
6710 build_java_interface_fn_ref (tree fn, tree instance)
6712 tree lookup_fn, method, idx;
6713 tree klass_ref, iface, iface_ref;
6716 if (!java_iface_lookup_fn)
6718 tree ftype = build_function_type_list (ptr_type_node,
6719 ptr_type_node, ptr_type_node,
6720 java_int_type_node, NULL_TREE);
6721 java_iface_lookup_fn
6722 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
6723 0, NOT_BUILT_IN, NULL, NULL_TREE);
6726 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
6727 This is the first entry in the vtable. */
6728 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
6729 tf_warning_or_error),
6732 /* Get the java.lang.Class pointer for the interface being called. */
6733 iface = DECL_CONTEXT (fn);
6734 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
6735 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
6736 || DECL_CONTEXT (iface_ref) != iface)
6738 error ("could not find class$ field in java interface type %qT",
6740 return error_mark_node;
6742 iface_ref = build_address (iface_ref);
6743 iface_ref = convert (build_pointer_type (iface), iface_ref);
6745 /* Determine the itable index of FN. */
6747 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
6749 if (!DECL_VIRTUAL_P (method))
6755 idx = build_int_cst (NULL_TREE, i);
6757 lookup_fn = build1 (ADDR_EXPR,
6758 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
6759 java_iface_lookup_fn);
6760 return build_call_nary (ptr_type_node, lookup_fn,
6761 3, klass_ref, iface_ref, idx);
6764 /* Returns the value to use for the in-charge parameter when making a
6765 call to a function with the indicated NAME.
6767 FIXME:Can't we find a neater way to do this mapping? */
6770 in_charge_arg_for_name (tree name)
6772 if (name == base_ctor_identifier
6773 || name == base_dtor_identifier)
6774 return integer_zero_node;
6775 else if (name == complete_ctor_identifier)
6776 return integer_one_node;
6777 else if (name == complete_dtor_identifier)
6778 return integer_two_node;
6779 else if (name == deleting_dtor_identifier)
6780 return integer_three_node;
6782 /* This function should only be called with one of the names listed
6788 /* Build a call to a constructor, destructor, or an assignment
6789 operator for INSTANCE, an expression with class type. NAME
6790 indicates the special member function to call; *ARGS are the
6791 arguments. ARGS may be NULL. This may change ARGS. BINFO
6792 indicates the base of INSTANCE that is to be passed as the `this'
6793 parameter to the member function called.
6795 FLAGS are the LOOKUP_* flags to use when processing the call.
6797 If NAME indicates a complete object constructor, INSTANCE may be
6798 NULL_TREE. In this case, the caller will call build_cplus_new to
6799 store the newly constructed object into a VAR_DECL. */
6802 build_special_member_call (tree instance, tree name, VEC(tree,gc) **args,
6803 tree binfo, int flags, tsubst_flags_t complain)
6806 /* The type of the subobject to be constructed or destroyed. */
6808 VEC(tree,gc) *allocated = NULL;
6811 gcc_assert (name == complete_ctor_identifier
6812 || name == base_ctor_identifier
6813 || name == complete_dtor_identifier
6814 || name == base_dtor_identifier
6815 || name == deleting_dtor_identifier
6816 || name == ansi_assopname (NOP_EXPR));
6819 /* Resolve the name. */
6820 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
6821 return error_mark_node;
6823 binfo = TYPE_BINFO (binfo);
6826 gcc_assert (binfo != NULL_TREE);
6828 class_type = BINFO_TYPE (binfo);
6830 /* Handle the special case where INSTANCE is NULL_TREE. */
6831 if (name == complete_ctor_identifier && !instance)
6833 instance = build_int_cst (build_pointer_type (class_type), 0);
6834 instance = build1 (INDIRECT_REF, class_type, instance);
6838 if (name == complete_dtor_identifier
6839 || name == base_dtor_identifier
6840 || name == deleting_dtor_identifier)
6841 gcc_assert (args == NULL || VEC_empty (tree, *args));
6843 /* Convert to the base class, if necessary. */
6844 if (!same_type_ignoring_top_level_qualifiers_p
6845 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
6847 if (name != ansi_assopname (NOP_EXPR))
6848 /* For constructors and destructors, either the base is
6849 non-virtual, or it is virtual but we are doing the
6850 conversion from a constructor or destructor for the
6851 complete object. In either case, we can convert
6853 instance = convert_to_base_statically (instance, binfo);
6855 /* However, for assignment operators, we must convert
6856 dynamically if the base is virtual. */
6857 instance = build_base_path (PLUS_EXPR, instance,
6858 binfo, /*nonnull=*/1);
6862 gcc_assert (instance != NULL_TREE);
6864 fns = lookup_fnfields (binfo, name, 1);
6866 /* When making a call to a constructor or destructor for a subobject
6867 that uses virtual base classes, pass down a pointer to a VTT for
6869 if ((name == base_ctor_identifier
6870 || name == base_dtor_identifier)
6871 && CLASSTYPE_VBASECLASSES (class_type))
6876 /* If the current function is a complete object constructor
6877 or destructor, then we fetch the VTT directly.
6878 Otherwise, we look it up using the VTT we were given. */
6879 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
6880 vtt = decay_conversion (vtt);
6881 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
6882 build2 (EQ_EXPR, boolean_type_node,
6883 current_in_charge_parm, integer_zero_node),
6886 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
6887 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
6888 BINFO_SUBVTT_INDEX (binfo));
6892 allocated = make_tree_vector ();
6896 VEC_safe_insert (tree, gc, *args, 0, sub_vtt);
6899 ret = build_new_method_call (instance, fns, args,
6900 TYPE_BINFO (BINFO_TYPE (binfo)),
6904 if (allocated != NULL)
6905 release_tree_vector (allocated);
6910 /* Return the NAME, as a C string. The NAME indicates a function that
6911 is a member of TYPE. *FREE_P is set to true if the caller must
6912 free the memory returned.
6914 Rather than go through all of this, we should simply set the names
6915 of constructors and destructors appropriately, and dispense with
6916 ctor_identifier, dtor_identifier, etc. */
6919 name_as_c_string (tree name, tree type, bool *free_p)
6923 /* Assume that we will not allocate memory. */
6925 /* Constructors and destructors are special. */
6926 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
6929 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
6930 /* For a destructor, add the '~'. */
6931 if (name == complete_dtor_identifier
6932 || name == base_dtor_identifier
6933 || name == deleting_dtor_identifier)
6935 pretty_name = concat ("~", pretty_name, NULL);
6936 /* Remember that we need to free the memory allocated. */
6940 else if (IDENTIFIER_TYPENAME_P (name))
6942 pretty_name = concat ("operator ",
6943 type_as_string_translate (TREE_TYPE (name),
6944 TFF_PLAIN_IDENTIFIER),
6946 /* Remember that we need to free the memory allocated. */
6950 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
6955 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6956 be set, upon return, to the function called. ARGS may be NULL.
6957 This may change ARGS. */
6960 build_new_method_call_1 (tree instance, tree fns, VEC(tree,gc) **args,
6961 tree conversion_path, int flags,
6962 tree *fn_p, tsubst_flags_t complain)
6964 struct z_candidate *candidates = 0, *cand;
6965 tree explicit_targs = NULL_TREE;
6966 tree basetype = NULL_TREE;
6969 tree first_mem_arg = NULL_TREE;
6972 bool skip_first_for_error;
6973 VEC(tree,gc) *user_args;
6976 int template_only = 0;
6980 VEC(tree,gc) *orig_args = NULL;
6983 gcc_assert (instance != NULL_TREE);
6985 /* We don't know what function we're going to call, yet. */
6989 if (error_operand_p (instance)
6990 || !fns || error_operand_p (fns))
6991 return error_mark_node;
6993 if (!BASELINK_P (fns))
6995 if (complain & tf_error)
6996 error ("call to non-function %qD", fns);
6997 return error_mark_node;
7000 orig_instance = instance;
7003 /* Dismantle the baselink to collect all the information we need. */
7004 if (!conversion_path)
7005 conversion_path = BASELINK_BINFO (fns);
7006 access_binfo = BASELINK_ACCESS_BINFO (fns);
7007 optype = BASELINK_OPTYPE (fns);
7008 fns = BASELINK_FUNCTIONS (fns);
7009 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7011 explicit_targs = TREE_OPERAND (fns, 1);
7012 fns = TREE_OPERAND (fns, 0);
7015 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
7016 || TREE_CODE (fns) == TEMPLATE_DECL
7017 || TREE_CODE (fns) == OVERLOAD);
7018 fn = get_first_fn (fns);
7019 name = DECL_NAME (fn);
7021 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
7022 gcc_assert (CLASS_TYPE_P (basetype));
7024 if (processing_template_decl)
7026 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
7027 instance = build_non_dependent_expr (instance);
7029 make_args_non_dependent (*args);
7032 user_args = args == NULL ? NULL : *args;
7033 /* Under DR 147 A::A() is an invalid constructor call,
7034 not a functional cast. */
7035 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
7037 if (! (complain & tf_error))
7038 return error_mark_node;
7040 permerror (input_location,
7041 "cannot call constructor %<%T::%D%> directly",
7043 permerror (input_location, " for a function-style cast, remove the "
7044 "redundant %<::%D%>", name);
7045 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
7050 /* Figure out whether to skip the first argument for the error
7051 message we will display to users if an error occurs. We don't
7052 want to display any compiler-generated arguments. The "this"
7053 pointer hasn't been added yet. However, we must remove the VTT
7054 pointer if this is a call to a base-class constructor or
7056 skip_first_for_error = false;
7057 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7059 /* Callers should explicitly indicate whether they want to construct
7060 the complete object or just the part without virtual bases. */
7061 gcc_assert (name != ctor_identifier);
7062 /* Similarly for destructors. */
7063 gcc_assert (name != dtor_identifier);
7064 /* Remove the VTT pointer, if present. */
7065 if ((name == base_ctor_identifier || name == base_dtor_identifier)
7066 && CLASSTYPE_VBASECLASSES (basetype))
7067 skip_first_for_error = true;
7070 /* Process the argument list. */
7071 if (args != NULL && *args != NULL)
7073 *args = resolve_args (*args, complain);
7075 return error_mark_node;
7078 instance_ptr = build_this (instance);
7080 /* It's OK to call destructors and constructors on cv-qualified objects.
7081 Therefore, convert the INSTANCE_PTR to the unqualified type, if
7083 if (DECL_DESTRUCTOR_P (fn)
7084 || DECL_CONSTRUCTOR_P (fn))
7086 tree type = build_pointer_type (basetype);
7087 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
7088 instance_ptr = build_nop (type, instance_ptr);
7090 if (DECL_DESTRUCTOR_P (fn))
7091 name = complete_dtor_identifier;
7093 first_mem_arg = instance_ptr;
7095 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7096 p = conversion_obstack_alloc (0);
7098 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
7099 initializer, not T({ }). */
7100 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !VEC_empty (tree, *args)
7101 && BRACE_ENCLOSED_INITIALIZER_P (VEC_index (tree, *args, 0))
7102 && CONSTRUCTOR_IS_DIRECT_INIT (VEC_index (tree, *args, 0)))
7104 gcc_assert (VEC_length (tree, *args) == 1
7105 && !(flags & LOOKUP_ONLYCONVERTING));
7107 add_list_candidates (fns, first_mem_arg, VEC_index (tree, *args, 0),
7108 basetype, explicit_targs, template_only,
7109 conversion_path, access_binfo, flags, &candidates);
7113 add_candidates (fns, first_mem_arg, user_args, optype,
7114 explicit_targs, template_only, conversion_path,
7115 access_binfo, flags, &candidates);
7117 any_viable_p = false;
7118 candidates = splice_viable (candidates, pedantic, &any_viable_p);
7122 if (complain & tf_error)
7124 if (!COMPLETE_OR_OPEN_TYPE_P (basetype))
7125 cxx_incomplete_type_error (instance_ptr, basetype);
7127 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
7128 basetype, optype, build_tree_list_vec (user_args),
7129 TREE_TYPE (TREE_TYPE (instance_ptr)));
7136 pretty_name = name_as_c_string (name, basetype, &free_p);
7137 arglist = build_tree_list_vec (user_args);
7138 if (skip_first_for_error)
7139 arglist = TREE_CHAIN (arglist);
7140 error ("no matching function for call to %<%T::%s(%A)%#V%>",
7141 basetype, pretty_name, arglist,
7142 TREE_TYPE (TREE_TYPE (instance_ptr)));
7146 print_z_candidates (location_of (name), candidates);
7148 call = error_mark_node;
7152 cand = tourney (candidates);
7159 if (complain & tf_error)
7161 pretty_name = name_as_c_string (name, basetype, &free_p);
7162 arglist = build_tree_list_vec (user_args);
7163 if (skip_first_for_error)
7164 arglist = TREE_CHAIN (arglist);
7165 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
7167 print_z_candidates (location_of (name), candidates);
7171 call = error_mark_node;
7177 if (!(flags & LOOKUP_NONVIRTUAL)
7178 && DECL_PURE_VIRTUAL_P (fn)
7179 && instance == current_class_ref
7180 && (DECL_CONSTRUCTOR_P (current_function_decl)
7181 || DECL_DESTRUCTOR_P (current_function_decl))
7182 && (complain & tf_warning))
7183 /* This is not an error, it is runtime undefined
7185 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
7186 "pure virtual %q#D called from constructor"
7187 : "pure virtual %q#D called from destructor"),
7190 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
7191 && is_dummy_object (instance_ptr))
7193 if (complain & tf_error)
7194 error ("cannot call member function %qD without object",
7196 call = error_mark_node;
7200 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
7201 && resolves_to_fixed_type_p (instance, 0))
7202 flags |= LOOKUP_NONVIRTUAL;
7204 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
7205 /* Now we know what function is being called. */
7208 /* Build the actual CALL_EXPR. */
7209 call = build_over_call (cand, flags, complain);
7210 /* In an expression of the form `a->f()' where `f' turns
7211 out to be a static member function, `a' is
7212 none-the-less evaluated. */
7213 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
7214 && !is_dummy_object (instance_ptr)
7215 && TREE_SIDE_EFFECTS (instance_ptr))
7216 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
7217 instance_ptr, call);
7218 else if (call != error_mark_node
7219 && DECL_DESTRUCTOR_P (cand->fn)
7220 && !VOID_TYPE_P (TREE_TYPE (call)))
7221 /* An explicit call of the form "x->~X()" has type
7222 "void". However, on platforms where destructors
7223 return "this" (i.e., those where
7224 targetm.cxx.cdtor_returns_this is true), such calls
7225 will appear to have a return value of pointer type
7226 to the low-level call machinery. We do not want to
7227 change the low-level machinery, since we want to be
7228 able to optimize "delete f()" on such platforms as
7229 "operator delete(~X(f()))" (rather than generating
7230 "t = f(), ~X(t), operator delete (t)"). */
7231 call = build_nop (void_type_node, call);
7236 if (processing_template_decl && call != error_mark_node)
7238 bool cast_to_void = false;
7240 if (TREE_CODE (call) == COMPOUND_EXPR)
7241 call = TREE_OPERAND (call, 1);
7242 else if (TREE_CODE (call) == NOP_EXPR)
7244 cast_to_void = true;
7245 call = TREE_OPERAND (call, 0);
7247 if (TREE_CODE (call) == INDIRECT_REF)
7248 call = TREE_OPERAND (call, 0);
7249 call = (build_min_non_dep_call_vec
7251 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
7252 orig_instance, orig_fns, NULL_TREE),
7254 call = convert_from_reference (call);
7256 call = build_nop (void_type_node, call);
7259 /* Free all the conversions we allocated. */
7260 obstack_free (&conversion_obstack, p);
7262 if (orig_args != NULL)
7263 release_tree_vector (orig_args);
7268 /* Wrapper for above. */
7271 build_new_method_call (tree instance, tree fns, VEC(tree,gc) **args,
7272 tree conversion_path, int flags,
7273 tree *fn_p, tsubst_flags_t complain)
7276 bool subtime = timevar_cond_start (TV_OVERLOAD);
7277 ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags,
7279 timevar_cond_stop (TV_OVERLOAD, subtime);
7283 /* Returns true iff standard conversion sequence ICS1 is a proper
7284 subsequence of ICS2. */
7287 is_subseq (conversion *ics1, conversion *ics2)
7289 /* We can assume that a conversion of the same code
7290 between the same types indicates a subsequence since we only get
7291 here if the types we are converting from are the same. */
7293 while (ics1->kind == ck_rvalue
7294 || ics1->kind == ck_lvalue)
7295 ics1 = ics1->u.next;
7299 while (ics2->kind == ck_rvalue
7300 || ics2->kind == ck_lvalue)
7301 ics2 = ics2->u.next;
7303 if (ics2->kind == ck_user
7304 || ics2->kind == ck_ambig
7305 || ics2->kind == ck_aggr
7306 || ics2->kind == ck_list
7307 || ics2->kind == ck_identity)
7308 /* At this point, ICS1 cannot be a proper subsequence of
7309 ICS2. We can get a USER_CONV when we are comparing the
7310 second standard conversion sequence of two user conversion
7314 ics2 = ics2->u.next;
7316 if (ics2->kind == ics1->kind
7317 && same_type_p (ics2->type, ics1->type)
7318 && same_type_p (ics2->u.next->type,
7319 ics1->u.next->type))
7324 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
7325 be any _TYPE nodes. */
7328 is_properly_derived_from (tree derived, tree base)
7330 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
7333 /* We only allow proper derivation here. The DERIVED_FROM_P macro
7334 considers every class derived from itself. */
7335 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
7336 && DERIVED_FROM_P (base, derived));
7339 /* We build the ICS for an implicit object parameter as a pointer
7340 conversion sequence. However, such a sequence should be compared
7341 as if it were a reference conversion sequence. If ICS is the
7342 implicit conversion sequence for an implicit object parameter,
7343 modify it accordingly. */
7346 maybe_handle_implicit_object (conversion **ics)
7350 /* [over.match.funcs]
7352 For non-static member functions, the type of the
7353 implicit object parameter is "reference to cv X"
7354 where X is the class of which the function is a
7355 member and cv is the cv-qualification on the member
7356 function declaration. */
7357 conversion *t = *ics;
7358 tree reference_type;
7360 /* The `this' parameter is a pointer to a class type. Make the
7361 implicit conversion talk about a reference to that same class
7363 reference_type = TREE_TYPE (t->type);
7364 reference_type = build_reference_type (reference_type);
7366 if (t->kind == ck_qual)
7368 if (t->kind == ck_ptr)
7370 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
7371 t = direct_reference_binding (reference_type, t);
7373 t->rvaluedness_matches_p = 0;
7378 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
7379 and return the initial reference binding conversion. Otherwise,
7380 leave *ICS unchanged and return NULL. */
7383 maybe_handle_ref_bind (conversion **ics)
7385 if ((*ics)->kind == ck_ref_bind)
7387 conversion *old_ics = *ics;
7388 *ics = old_ics->u.next;
7389 (*ics)->user_conv_p = old_ics->user_conv_p;
7396 /* Compare two implicit conversion sequences according to the rules set out in
7397 [over.ics.rank]. Return values:
7399 1: ics1 is better than ics2
7400 -1: ics2 is better than ics1
7401 0: ics1 and ics2 are indistinguishable */
7404 compare_ics (conversion *ics1, conversion *ics2)
7410 tree deref_from_type1 = NULL_TREE;
7411 tree deref_from_type2 = NULL_TREE;
7412 tree deref_to_type1 = NULL_TREE;
7413 tree deref_to_type2 = NULL_TREE;
7414 conversion_rank rank1, rank2;
7416 /* REF_BINDING is nonzero if the result of the conversion sequence
7417 is a reference type. In that case REF_CONV is the reference
7418 binding conversion. */
7419 conversion *ref_conv1;
7420 conversion *ref_conv2;
7422 /* Handle implicit object parameters. */
7423 maybe_handle_implicit_object (&ics1);
7424 maybe_handle_implicit_object (&ics2);
7426 /* Handle reference parameters. */
7427 ref_conv1 = maybe_handle_ref_bind (&ics1);
7428 ref_conv2 = maybe_handle_ref_bind (&ics2);
7430 /* List-initialization sequence L1 is a better conversion sequence than
7431 list-initialization sequence L2 if L1 converts to
7432 std::initializer_list<X> for some X and L2 does not. */
7433 if (ics1->kind == ck_list && ics2->kind != ck_list)
7435 if (ics2->kind == ck_list && ics1->kind != ck_list)
7440 When comparing the basic forms of implicit conversion sequences (as
7441 defined in _over.best.ics_)
7443 --a standard conversion sequence (_over.ics.scs_) is a better
7444 conversion sequence than a user-defined conversion sequence
7445 or an ellipsis conversion sequence, and
7447 --a user-defined conversion sequence (_over.ics.user_) is a
7448 better conversion sequence than an ellipsis conversion sequence
7449 (_over.ics.ellipsis_). */
7450 rank1 = CONVERSION_RANK (ics1);
7451 rank2 = CONVERSION_RANK (ics2);
7455 else if (rank1 < rank2)
7458 if (rank1 == cr_bad)
7460 /* Both ICS are bad. We try to make a decision based on what would
7461 have happened if they'd been good. This is not an extension,
7462 we'll still give an error when we build up the call; this just
7463 helps us give a more helpful error message. */
7464 rank1 = BAD_CONVERSION_RANK (ics1);
7465 rank2 = BAD_CONVERSION_RANK (ics2);
7469 else if (rank1 < rank2)
7472 /* We couldn't make up our minds; try to figure it out below. */
7475 if (ics1->ellipsis_p)
7476 /* Both conversions are ellipsis conversions. */
7479 /* User-defined conversion sequence U1 is a better conversion sequence
7480 than another user-defined conversion sequence U2 if they contain the
7481 same user-defined conversion operator or constructor and if the sec-
7482 ond standard conversion sequence of U1 is better than the second
7483 standard conversion sequence of U2. */
7485 /* Handle list-conversion with the same code even though it isn't always
7486 ranked as a user-defined conversion and it doesn't have a second
7487 standard conversion sequence; it will still have the desired effect.
7488 Specifically, we need to do the reference binding comparison at the
7489 end of this function. */
7491 if (ics1->user_conv_p || ics1->kind == ck_list)
7496 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
7497 if (t1->kind == ck_ambig || t1->kind == ck_aggr
7498 || t1->kind == ck_list)
7500 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
7501 if (t2->kind == ck_ambig || t2->kind == ck_aggr
7502 || t2->kind == ck_list)
7505 if (t1->kind != t2->kind)
7507 else if (t1->kind == ck_user)
7509 if (t1->cand->fn != t2->cand->fn)
7514 /* For ambiguous or aggregate conversions, use the target type as
7515 a proxy for the conversion function. */
7516 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
7520 /* We can just fall through here, after setting up
7521 FROM_TYPE1 and FROM_TYPE2. */
7522 from_type1 = t1->type;
7523 from_type2 = t2->type;
7530 /* We're dealing with two standard conversion sequences.
7534 Standard conversion sequence S1 is a better conversion
7535 sequence than standard conversion sequence S2 if
7537 --S1 is a proper subsequence of S2 (comparing the conversion
7538 sequences in the canonical form defined by _over.ics.scs_,
7539 excluding any Lvalue Transformation; the identity
7540 conversion sequence is considered to be a subsequence of
7541 any non-identity conversion sequence */
7544 while (t1->kind != ck_identity)
7546 from_type1 = t1->type;
7549 while (t2->kind != ck_identity)
7551 from_type2 = t2->type;
7554 /* One sequence can only be a subsequence of the other if they start with
7555 the same type. They can start with different types when comparing the
7556 second standard conversion sequence in two user-defined conversion
7558 if (same_type_p (from_type1, from_type2))
7560 if (is_subseq (ics1, ics2))
7562 if (is_subseq (ics2, ics1))
7570 --the rank of S1 is better than the rank of S2 (by the rules
7573 Standard conversion sequences are ordered by their ranks: an Exact
7574 Match is a better conversion than a Promotion, which is a better
7575 conversion than a Conversion.
7577 Two conversion sequences with the same rank are indistinguishable
7578 unless one of the following rules applies:
7580 --A conversion that does not a convert a pointer, pointer to member,
7581 or std::nullptr_t to bool is better than one that does.
7583 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
7584 so that we do not have to check it explicitly. */
7585 if (ics1->rank < ics2->rank)
7587 else if (ics2->rank < ics1->rank)
7590 to_type1 = ics1->type;
7591 to_type2 = ics2->type;
7593 /* A conversion from scalar arithmetic type to complex is worse than a
7594 conversion between scalar arithmetic types. */
7595 if (same_type_p (from_type1, from_type2)
7596 && ARITHMETIC_TYPE_P (from_type1)
7597 && ARITHMETIC_TYPE_P (to_type1)
7598 && ARITHMETIC_TYPE_P (to_type2)
7599 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
7600 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
7602 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
7608 if (TYPE_PTR_P (from_type1)
7609 && TYPE_PTR_P (from_type2)
7610 && TYPE_PTR_P (to_type1)
7611 && TYPE_PTR_P (to_type2))
7613 deref_from_type1 = TREE_TYPE (from_type1);
7614 deref_from_type2 = TREE_TYPE (from_type2);
7615 deref_to_type1 = TREE_TYPE (to_type1);
7616 deref_to_type2 = TREE_TYPE (to_type2);
7618 /* The rules for pointers to members A::* are just like the rules
7619 for pointers A*, except opposite: if B is derived from A then
7620 A::* converts to B::*, not vice versa. For that reason, we
7621 switch the from_ and to_ variables here. */
7622 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
7623 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
7624 || (TYPE_PTRMEMFUNC_P (from_type1)
7625 && TYPE_PTRMEMFUNC_P (from_type2)
7626 && TYPE_PTRMEMFUNC_P (to_type1)
7627 && TYPE_PTRMEMFUNC_P (to_type2)))
7629 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
7630 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
7631 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
7632 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
7635 if (deref_from_type1 != NULL_TREE
7636 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
7637 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
7639 /* This was one of the pointer or pointer-like conversions.
7643 --If class B is derived directly or indirectly from class A,
7644 conversion of B* to A* is better than conversion of B* to
7645 void*, and conversion of A* to void* is better than
7646 conversion of B* to void*. */
7647 if (TREE_CODE (deref_to_type1) == VOID_TYPE
7648 && TREE_CODE (deref_to_type2) == VOID_TYPE)
7650 if (is_properly_derived_from (deref_from_type1,
7653 else if (is_properly_derived_from (deref_from_type2,
7657 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
7658 || TREE_CODE (deref_to_type2) == VOID_TYPE)
7660 if (same_type_p (deref_from_type1, deref_from_type2))
7662 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
7664 if (is_properly_derived_from (deref_from_type1,
7668 /* We know that DEREF_TO_TYPE1 is `void' here. */
7669 else if (is_properly_derived_from (deref_from_type1,
7674 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
7675 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
7679 --If class B is derived directly or indirectly from class A
7680 and class C is derived directly or indirectly from B,
7682 --conversion of C* to B* is better than conversion of C* to
7685 --conversion of B* to A* is better than conversion of C* to
7687 if (same_type_p (deref_from_type1, deref_from_type2))
7689 if (is_properly_derived_from (deref_to_type1,
7692 else if (is_properly_derived_from (deref_to_type2,
7696 else if (same_type_p (deref_to_type1, deref_to_type2))
7698 if (is_properly_derived_from (deref_from_type2,
7701 else if (is_properly_derived_from (deref_from_type1,
7707 else if (CLASS_TYPE_P (non_reference (from_type1))
7708 && same_type_p (from_type1, from_type2))
7710 tree from = non_reference (from_type1);
7714 --binding of an expression of type C to a reference of type
7715 B& is better than binding an expression of type C to a
7716 reference of type A&
7718 --conversion of C to B is better than conversion of C to A, */
7719 if (is_properly_derived_from (from, to_type1)
7720 && is_properly_derived_from (from, to_type2))
7722 if (is_properly_derived_from (to_type1, to_type2))
7724 else if (is_properly_derived_from (to_type2, to_type1))
7728 else if (CLASS_TYPE_P (non_reference (to_type1))
7729 && same_type_p (to_type1, to_type2))
7731 tree to = non_reference (to_type1);
7735 --binding of an expression of type B to a reference of type
7736 A& is better than binding an expression of type C to a
7737 reference of type A&,
7739 --conversion of B to A is better than conversion of C to A */
7740 if (is_properly_derived_from (from_type1, to)
7741 && is_properly_derived_from (from_type2, to))
7743 if (is_properly_derived_from (from_type2, from_type1))
7745 else if (is_properly_derived_from (from_type1, from_type2))
7752 --S1 and S2 differ only in their qualification conversion and yield
7753 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
7754 qualification signature of type T1 is a proper subset of the cv-
7755 qualification signature of type T2 */
7756 if (ics1->kind == ck_qual
7757 && ics2->kind == ck_qual
7758 && same_type_p (from_type1, from_type2))
7760 int result = comp_cv_qual_signature (to_type1, to_type2);
7767 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
7768 to an implicit object parameter, and either S1 binds an lvalue reference
7769 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
7770 reference to an rvalue and S2 binds an lvalue reference
7771 (C++0x draft standard, 13.3.3.2)
7773 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
7774 types to which the references refer are the same type except for
7775 top-level cv-qualifiers, and the type to which the reference
7776 initialized by S2 refers is more cv-qualified than the type to
7777 which the reference initialized by S1 refers */
7779 if (ref_conv1 && ref_conv2)
7781 if (!ref_conv1->this_p && !ref_conv2->this_p
7782 && (TYPE_REF_IS_RVALUE (ref_conv1->type)
7783 != TYPE_REF_IS_RVALUE (ref_conv2->type)))
7785 if (ref_conv1->rvaluedness_matches_p)
7787 if (ref_conv2->rvaluedness_matches_p)
7791 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
7792 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
7793 TREE_TYPE (ref_conv1->type));
7796 /* Neither conversion sequence is better than the other. */
7800 /* The source type for this standard conversion sequence. */
7803 source_type (conversion *t)
7805 for (;; t = t->u.next)
7807 if (t->kind == ck_user
7808 || t->kind == ck_ambig
7809 || t->kind == ck_identity)
7815 /* Note a warning about preferring WINNER to LOSER. We do this by storing
7816 a pointer to LOSER and re-running joust to produce the warning if WINNER
7817 is actually used. */
7820 add_warning (struct z_candidate *winner, struct z_candidate *loser)
7822 candidate_warning *cw = (candidate_warning *)
7823 conversion_obstack_alloc (sizeof (candidate_warning));
7825 cw->next = winner->warnings;
7826 winner->warnings = cw;
7829 /* Compare two candidates for overloading as described in
7830 [over.match.best]. Return values:
7832 1: cand1 is better than cand2
7833 -1: cand2 is better than cand1
7834 0: cand1 and cand2 are indistinguishable */
7837 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
7840 int off1 = 0, off2 = 0;
7844 /* Candidates that involve bad conversions are always worse than those
7846 if (cand1->viable > cand2->viable)
7848 if (cand1->viable < cand2->viable)
7851 /* If we have two pseudo-candidates for conversions to the same type,
7852 or two candidates for the same function, arbitrarily pick one. */
7853 if (cand1->fn == cand2->fn
7854 && (IS_TYPE_OR_DECL_P (cand1->fn)))
7857 /* a viable function F1
7858 is defined to be a better function than another viable function F2 if
7859 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7860 ICSi(F2), and then */
7862 /* for some argument j, ICSj(F1) is a better conversion sequence than
7865 /* For comparing static and non-static member functions, we ignore
7866 the implicit object parameter of the non-static function. The
7867 standard says to pretend that the static function has an object
7868 parm, but that won't work with operator overloading. */
7869 len = cand1->num_convs;
7870 if (len != cand2->num_convs)
7872 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
7873 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
7875 gcc_assert (static_1 != static_2);
7886 for (i = 0; i < len; ++i)
7888 conversion *t1 = cand1->convs[i + off1];
7889 conversion *t2 = cand2->convs[i + off2];
7890 int comp = compare_ics (t1, t2);
7895 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
7896 == cr_std + cr_promotion)
7897 && t1->kind == ck_std
7898 && t2->kind == ck_std
7899 && TREE_CODE (t1->type) == INTEGER_TYPE
7900 && TREE_CODE (t2->type) == INTEGER_TYPE
7901 && (TYPE_PRECISION (t1->type)
7902 == TYPE_PRECISION (t2->type))
7903 && (TYPE_UNSIGNED (t1->u.next->type)
7904 || (TREE_CODE (t1->u.next->type)
7907 tree type = t1->u.next->type;
7909 struct z_candidate *w, *l;
7911 type1 = t1->type, type2 = t2->type,
7912 w = cand1, l = cand2;
7914 type1 = t2->type, type2 = t1->type,
7915 w = cand2, l = cand1;
7919 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
7920 type, type1, type2);
7921 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
7927 if (winner && comp != winner)
7936 /* warn about confusing overload resolution for user-defined conversions,
7937 either between a constructor and a conversion op, or between two
7939 if (winner && warn_conversion && cand1->second_conv
7940 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
7941 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
7943 struct z_candidate *w, *l;
7944 bool give_warning = false;
7947 w = cand1, l = cand2;
7949 w = cand2, l = cand1;
7951 /* We don't want to complain about `X::operator T1 ()'
7952 beating `X::operator T2 () const', when T2 is a no less
7953 cv-qualified version of T1. */
7954 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
7955 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
7957 tree t = TREE_TYPE (TREE_TYPE (l->fn));
7958 tree f = TREE_TYPE (TREE_TYPE (w->fn));
7960 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
7965 if (!comp_ptr_ttypes (t, f))
7966 give_warning = true;
7969 give_warning = true;
7975 tree source = source_type (w->convs[0]);
7976 if (! DECL_CONSTRUCTOR_P (w->fn))
7977 source = TREE_TYPE (source);
7978 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
7979 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
7980 source, w->second_conv->type))
7982 inform (input_location, " because conversion sequence for the argument is better");
7993 F1 is a non-template function and F2 is a template function
7996 if (!cand1->template_decl && cand2->template_decl)
7998 else if (cand1->template_decl && !cand2->template_decl)
8002 F1 and F2 are template functions and the function template for F1 is
8003 more specialized than the template for F2 according to the partial
8006 if (cand1->template_decl && cand2->template_decl)
8008 winner = more_specialized_fn
8009 (TI_TEMPLATE (cand1->template_decl),
8010 TI_TEMPLATE (cand2->template_decl),
8011 /* [temp.func.order]: The presence of unused ellipsis and default
8012 arguments has no effect on the partial ordering of function
8013 templates. add_function_candidate() will not have
8014 counted the "this" argument for constructors. */
8015 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
8021 the context is an initialization by user-defined conversion (see
8022 _dcl.init_ and _over.match.user_) and the standard conversion
8023 sequence from the return type of F1 to the destination type (i.e.,
8024 the type of the entity being initialized) is a better conversion
8025 sequence than the standard conversion sequence from the return type
8026 of F2 to the destination type. */
8028 if (cand1->second_conv)
8030 winner = compare_ics (cand1->second_conv, cand2->second_conv);
8035 /* Check whether we can discard a builtin candidate, either because we
8036 have two identical ones or matching builtin and non-builtin candidates.
8038 (Pedantically in the latter case the builtin which matched the user
8039 function should not be added to the overload set, but we spot it here.
8042 ... the builtin candidates include ...
8043 - do not have the same parameter type list as any non-template
8044 non-member candidate. */
8046 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
8047 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
8049 for (i = 0; i < len; ++i)
8050 if (!same_type_p (cand1->convs[i]->type,
8051 cand2->convs[i]->type))
8053 if (i == cand1->num_convs)
8055 if (cand1->fn == cand2->fn)
8056 /* Two built-in candidates; arbitrarily pick one. */
8058 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
8059 /* cand1 is built-in; prefer cand2. */
8062 /* cand2 is built-in; prefer cand1. */
8067 /* If the two function declarations represent the same function (this can
8068 happen with declarations in multiple scopes and arg-dependent lookup),
8069 arbitrarily choose one. But first make sure the default args we're
8071 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
8072 && equal_functions (cand1->fn, cand2->fn))
8074 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
8075 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
8077 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
8079 for (i = 0; i < len; ++i)
8081 /* Don't crash if the fn is variadic. */
8084 parms1 = TREE_CHAIN (parms1);
8085 parms2 = TREE_CHAIN (parms2);
8089 parms1 = TREE_CHAIN (parms1);
8091 parms2 = TREE_CHAIN (parms2);
8095 if (!cp_tree_equal (TREE_PURPOSE (parms1),
8096 TREE_PURPOSE (parms2)))
8100 permerror (input_location, "default argument mismatch in "
8101 "overload resolution");
8102 inform (input_location,
8103 " candidate 1: %q+#F", cand1->fn);
8104 inform (input_location,
8105 " candidate 2: %q+#F", cand2->fn);
8108 add_warning (cand1, cand2);
8111 parms1 = TREE_CHAIN (parms1);
8112 parms2 = TREE_CHAIN (parms2);
8120 /* Extension: If the worst conversion for one candidate is worse than the
8121 worst conversion for the other, take the first. */
8124 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
8125 struct z_candidate *w = 0, *l = 0;
8127 for (i = 0; i < len; ++i)
8129 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
8130 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
8131 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
8132 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
8135 winner = 1, w = cand1, l = cand2;
8137 winner = -1, w = cand2, l = cand1;
8140 /* Don't choose a deleted function over ambiguity. */
8141 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
8145 pedwarn (input_location, 0,
8146 "ISO C++ says that these are ambiguous, even "
8147 "though the worst conversion for the first is better than "
8148 "the worst conversion for the second:");
8149 print_z_candidate (_("candidate 1:"), w);
8150 print_z_candidate (_("candidate 2:"), l);
8158 gcc_assert (!winner);
8162 /* Given a list of candidates for overloading, find the best one, if any.
8163 This algorithm has a worst case of O(2n) (winner is last), and a best
8164 case of O(n/2) (totally ambiguous); much better than a sorting
8167 static struct z_candidate *
8168 tourney (struct z_candidate *candidates)
8170 struct z_candidate *champ = candidates, *challenger;
8172 int champ_compared_to_predecessor = 0;
8174 /* Walk through the list once, comparing each current champ to the next
8175 candidate, knocking out a candidate or two with each comparison. */
8177 for (challenger = champ->next; challenger; )
8179 fate = joust (champ, challenger, 0);
8181 challenger = challenger->next;
8186 champ = challenger->next;
8189 champ_compared_to_predecessor = 0;
8194 champ_compared_to_predecessor = 1;
8197 challenger = champ->next;
8201 /* Make sure the champ is better than all the candidates it hasn't yet
8202 been compared to. */
8204 for (challenger = candidates;
8206 && !(champ_compared_to_predecessor && challenger->next == champ);
8207 challenger = challenger->next)
8209 fate = joust (champ, challenger, 0);
8217 /* Returns nonzero if things of type FROM can be converted to TO. */
8220 can_convert (tree to, tree from)
8222 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT);
8225 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
8228 can_convert_arg (tree to, tree from, tree arg, int flags)
8234 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8235 p = conversion_obstack_alloc (0);
8237 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8239 ok_p = (t && !t->bad_p);
8241 /* Free all the conversions we allocated. */
8242 obstack_free (&conversion_obstack, p);
8247 /* Like can_convert_arg, but allows dubious conversions as well. */
8250 can_convert_arg_bad (tree to, tree from, tree arg, int flags)
8255 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8256 p = conversion_obstack_alloc (0);
8257 /* Try to perform the conversion. */
8258 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
8260 /* Free all the conversions we allocated. */
8261 obstack_free (&conversion_obstack, p);
8266 /* Convert EXPR to TYPE. Return the converted expression.
8268 Note that we allow bad conversions here because by the time we get to
8269 this point we are committed to doing the conversion. If we end up
8270 doing a bad conversion, convert_like will complain. */
8273 perform_implicit_conversion_flags (tree type, tree expr, tsubst_flags_t complain, int flags)
8278 if (error_operand_p (expr))
8279 return error_mark_node;
8281 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8282 p = conversion_obstack_alloc (0);
8284 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8290 if (complain & tf_error)
8292 /* If expr has unknown type, then it is an overloaded function.
8293 Call instantiate_type to get good error messages. */
8294 if (TREE_TYPE (expr) == unknown_type_node)
8295 instantiate_type (type, expr, complain);
8296 else if (invalid_nonstatic_memfn_p (expr, complain))
8297 /* We gave an error. */;
8299 error ("could not convert %qE from %qT to %qT", expr,
8300 TREE_TYPE (expr), type);
8302 expr = error_mark_node;
8304 else if (processing_template_decl)
8306 /* In a template, we are only concerned about determining the
8307 type of non-dependent expressions, so we do not have to
8308 perform the actual conversion. */
8309 if (TREE_TYPE (expr) != type)
8310 expr = build_nop (type, expr);
8313 expr = convert_like (conv, expr, complain);
8315 /* Free all the conversions we allocated. */
8316 obstack_free (&conversion_obstack, p);
8322 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
8324 return perform_implicit_conversion_flags (type, expr, complain, LOOKUP_IMPLICIT);
8327 /* Convert EXPR to TYPE (as a direct-initialization) if that is
8328 permitted. If the conversion is valid, the converted expression is
8329 returned. Otherwise, NULL_TREE is returned, except in the case
8330 that TYPE is a class type; in that case, an error is issued. If
8331 C_CAST_P is true, then this direction initialization is taking
8332 place as part of a static_cast being attempted as part of a C-style
8336 perform_direct_initialization_if_possible (tree type,
8339 tsubst_flags_t complain)
8344 if (type == error_mark_node || error_operand_p (expr))
8345 return error_mark_node;
8348 If the destination type is a (possibly cv-qualified) class type:
8350 -- If the initialization is direct-initialization ...,
8351 constructors are considered. ... If no constructor applies, or
8352 the overload resolution is ambiguous, the initialization is
8354 if (CLASS_TYPE_P (type))
8356 VEC(tree,gc) *args = make_tree_vector_single (expr);
8357 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
8358 &args, type, LOOKUP_NORMAL, complain);
8359 release_tree_vector (args);
8360 return build_cplus_new (type, expr, complain);
8363 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8364 p = conversion_obstack_alloc (0);
8366 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
8369 if (!conv || conv->bad_p)
8372 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
8373 /*issue_conversion_warnings=*/false,
8377 /* Free all the conversions we allocated. */
8378 obstack_free (&conversion_obstack, p);
8383 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
8384 is being bound to a temporary. Create and return a new VAR_DECL
8385 with the indicated TYPE; this variable will store the value to
8386 which the reference is bound. */
8389 make_temporary_var_for_ref_to_temp (tree decl, tree type)
8393 /* Create the variable. */
8394 var = create_temporary_var (type);
8396 /* Register the variable. */
8397 if (TREE_STATIC (decl))
8399 /* Namespace-scope or local static; give it a mangled name. */
8402 TREE_STATIC (var) = 1;
8403 name = mangle_ref_init_variable (decl);
8404 DECL_NAME (var) = name;
8405 SET_DECL_ASSEMBLER_NAME (var, name);
8406 var = pushdecl_top_level (var);
8409 /* Create a new cleanup level if necessary. */
8410 maybe_push_cleanup_level (type);
8415 /* EXPR is the initializer for a variable DECL of reference or
8416 std::initializer_list type. Create, push and return a new VAR_DECL
8417 for the initializer so that it will live as long as DECL. Any
8418 cleanup for the new variable is returned through CLEANUP, and the
8419 code to initialize the new variable is returned through INITP. */
8422 set_up_extended_ref_temp (tree decl, tree expr, tree *cleanup, tree *initp)
8428 /* Create the temporary variable. */
8429 type = TREE_TYPE (expr);
8430 var = make_temporary_var_for_ref_to_temp (decl, type);
8431 layout_decl (var, 0);
8432 /* If the rvalue is the result of a function call it will be
8433 a TARGET_EXPR. If it is some other construct (such as a
8434 member access expression where the underlying object is
8435 itself the result of a function call), turn it into a
8436 TARGET_EXPR here. It is important that EXPR be a
8437 TARGET_EXPR below since otherwise the INIT_EXPR will
8438 attempt to make a bitwise copy of EXPR to initialize
8440 if (TREE_CODE (expr) != TARGET_EXPR)
8441 expr = get_target_expr (expr);
8443 /* If the initializer is constant, put it in DECL_INITIAL so we get
8444 static initialization and use in constant expressions. */
8445 init = maybe_constant_init (expr);
8446 if (TREE_CONSTANT (init))
8448 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
8450 /* 5.19 says that a constant expression can include an
8451 lvalue-rvalue conversion applied to "a glvalue of literal type
8452 that refers to a non-volatile temporary object initialized
8453 with a constant expression". Rather than try to communicate
8454 that this VAR_DECL is a temporary, just mark it constexpr.
8456 Currently this is only useful for initializer_list temporaries,
8457 since reference vars can't appear in constant expressions. */
8458 DECL_DECLARED_CONSTEXPR_P (var) = true;
8459 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
8460 TREE_CONSTANT (var) = true;
8462 DECL_INITIAL (var) = init;
8466 /* Create the INIT_EXPR that will initialize the temporary
8468 init = build2 (INIT_EXPR, type, var, expr);
8469 if (at_function_scope_p ())
8471 add_decl_expr (var);
8473 if (TREE_STATIC (var))
8474 init = add_stmt_to_compound (init, register_dtor_fn (var));
8476 *cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error);
8478 /* We must be careful to destroy the temporary only
8479 after its initialization has taken place. If the
8480 initialization throws an exception, then the
8481 destructor should not be run. We cannot simply
8482 transform INIT into something like:
8484 (INIT, ({ CLEANUP_STMT; }))
8486 because emit_local_var always treats the
8487 initializer as a full-expression. Thus, the
8488 destructor would run too early; it would run at the
8489 end of initializing the reference variable, rather
8490 than at the end of the block enclosing the
8493 The solution is to pass back a cleanup expression
8494 which the caller is responsible for attaching to
8495 the statement tree. */
8499 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
8500 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
8501 static_aggregates = tree_cons (NULL_TREE, var,
8509 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
8510 initializing a variable of that TYPE. If DECL is non-NULL, it is
8511 the VAR_DECL being initialized with the EXPR. (In that case, the
8512 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
8513 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
8514 return, if *CLEANUP is no longer NULL, it will be an expression
8515 that should be pushed as a cleanup after the returned expression
8516 is used to initialize DECL.
8518 Return the converted expression. */
8521 initialize_reference (tree type, tree expr, tree decl, tree *cleanup,
8522 tsubst_flags_t complain)
8527 if (type == error_mark_node || error_operand_p (expr))
8528 return error_mark_node;
8530 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8531 p = conversion_obstack_alloc (0);
8533 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
8535 if (!conv || conv->bad_p)
8537 if (complain & tf_error)
8539 if (!CP_TYPE_CONST_P (TREE_TYPE (type))
8540 && !TYPE_REF_IS_RVALUE (type)
8541 && !real_lvalue_p (expr))
8542 error ("invalid initialization of non-const reference of "
8543 "type %qT from an rvalue of type %qT",
8544 type, TREE_TYPE (expr));
8546 error ("invalid initialization of reference of type "
8547 "%qT from expression of type %qT", type,
8550 return error_mark_node;
8553 /* If DECL is non-NULL, then this special rule applies:
8557 The temporary to which the reference is bound or the temporary
8558 that is the complete object to which the reference is bound
8559 persists for the lifetime of the reference.
8561 The temporaries created during the evaluation of the expression
8562 initializing the reference, except the temporary to which the
8563 reference is bound, are destroyed at the end of the
8564 full-expression in which they are created.
8566 In that case, we store the converted expression into a new
8567 VAR_DECL in a new scope.
8569 However, we want to be careful not to create temporaries when
8570 they are not required. For example, given:
8573 struct D : public B {};
8577 there is no need to copy the return value from "f"; we can just
8578 extend its lifetime. Similarly, given:
8581 struct T { operator S(); };
8585 we can extend the lifetime of the return value of the conversion
8587 gcc_assert (conv->kind == ck_ref_bind);
8591 tree base_conv_type;
8593 /* Skip over the REF_BIND. */
8594 conv = conv->u.next;
8595 /* If the next conversion is a BASE_CONV, skip that too -- but
8596 remember that the conversion was required. */
8597 if (conv->kind == ck_base)
8599 base_conv_type = conv->type;
8600 conv = conv->u.next;
8603 base_conv_type = NULL_TREE;
8604 /* Perform the remainder of the conversion. */
8605 expr = convert_like_real (conv, expr,
8606 /*fn=*/NULL_TREE, /*argnum=*/0,
8608 /*issue_conversion_warnings=*/true,
8610 tf_warning_or_error);
8611 if (error_operand_p (expr))
8612 expr = error_mark_node;
8615 if (!lvalue_or_rvalue_with_address_p (expr))
8618 var = set_up_extended_ref_temp (decl, expr, cleanup, &init);
8619 /* Use its address to initialize the reference variable. */
8620 expr = build_address (var);
8622 expr = convert_to_base (expr,
8623 build_pointer_type (base_conv_type),
8624 /*check_access=*/true,
8625 /*nonnull=*/true, complain);
8627 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
8630 /* Take the address of EXPR. */
8631 expr = cp_build_addr_expr (expr, tf_warning_or_error);
8632 /* If a BASE_CONV was required, perform it now. */
8634 expr = (perform_implicit_conversion
8635 (build_pointer_type (base_conv_type), expr,
8636 tf_warning_or_error));
8637 expr = build_nop (type, expr);
8641 /* Perform the conversion. */
8642 expr = convert_like (conv, expr, tf_warning_or_error);
8644 /* Free all the conversions we allocated. */
8645 obstack_free (&conversion_obstack, p);
8650 /* Returns true iff TYPE is some variant of std::initializer_list. */
8653 is_std_init_list (tree type)
8655 /* Look through typedefs. */
8658 type = TYPE_MAIN_VARIANT (type);
8659 return (CLASS_TYPE_P (type)
8660 && CP_TYPE_CONTEXT (type) == std_node
8661 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
8664 /* Returns true iff DECL is a list constructor: i.e. a constructor which
8665 will accept an argument list of a single std::initializer_list<T>. */
8668 is_list_ctor (tree decl)
8670 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
8673 if (!args || args == void_list_node)
8676 arg = non_reference (TREE_VALUE (args));
8677 if (!is_std_init_list (arg))
8680 args = TREE_CHAIN (args);
8682 if (args && args != void_list_node && !TREE_PURPOSE (args))
8683 /* There are more non-defaulted parms. */
8689 #include "gt-cp-call.h"