1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987-2015 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com) and
4 modified by Brendan Kehoe (brendan@cygnus.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* High-level class interface. */
27 #include "coretypes.h"
32 #include "double-int.h"
39 #include "stor-layout.h"
40 #include "trans-mem.h"
41 #include "stringpool.h"
45 #include "diagnostic-core.h"
49 #include "langhooks.h"
50 #include "c-family/c-objc.h"
54 #include "plugin-api.h"
55 #include "hard-reg-set.h"
61 #include "internal-fn.h"
63 /* The various kinds of conversion. */
65 typedef enum conversion_kind {
81 /* The rank of the conversion. Order of the enumerals matters; better
82 conversions should come earlier in the list. */
84 typedef enum conversion_rank {
95 /* An implicit conversion sequence, in the sense of [over.best.ics].
96 The first conversion to be performed is at the end of the chain.
97 That conversion is always a cr_identity conversion. */
99 typedef struct conversion conversion;
101 /* The kind of conversion represented by this step. */
102 conversion_kind kind;
103 /* The rank of this conversion. */
104 conversion_rank rank;
105 BOOL_BITFIELD user_conv_p : 1;
106 BOOL_BITFIELD ellipsis_p : 1;
107 BOOL_BITFIELD this_p : 1;
108 /* True if this conversion would be permitted with a bending of
109 language standards, e.g. disregarding pointer qualifiers or
110 converting integers to pointers. */
111 BOOL_BITFIELD bad_p : 1;
112 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
113 temporary should be created to hold the result of the
115 BOOL_BITFIELD need_temporary_p : 1;
116 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
117 from a pointer-to-derived to pointer-to-base is being performed. */
118 BOOL_BITFIELD base_p : 1;
119 /* If KIND is ck_ref_bind, true when either an lvalue reference is
120 being bound to an lvalue expression or an rvalue reference is
121 being bound to an rvalue expression. If KIND is ck_rvalue,
122 true when we should treat an lvalue as an rvalue (12.8p33). If
123 KIND is ck_base, always false. */
124 BOOL_BITFIELD rvaluedness_matches_p: 1;
125 BOOL_BITFIELD check_narrowing: 1;
126 /* The type of the expression resulting from the conversion. */
129 /* The next conversion in the chain. Since the conversions are
130 arranged from outermost to innermost, the NEXT conversion will
131 actually be performed before this conversion. This variant is
132 used only when KIND is neither ck_identity, ck_ambig nor
133 ck_list. Please use the next_conversion function instead
134 of using this field directly. */
136 /* The expression at the beginning of the conversion chain. This
137 variant is used only if KIND is ck_identity or ck_ambig. */
139 /* The array of conversions for an initializer_list, so this
140 variant is used only when KIN D is ck_list. */
143 /* The function candidate corresponding to this conversion
144 sequence. This field is only used if KIND is ck_user. */
145 struct z_candidate *cand;
148 #define CONVERSION_RANK(NODE) \
149 ((NODE)->bad_p ? cr_bad \
150 : (NODE)->ellipsis_p ? cr_ellipsis \
151 : (NODE)->user_conv_p ? cr_user \
154 #define BAD_CONVERSION_RANK(NODE) \
155 ((NODE)->ellipsis_p ? cr_ellipsis \
156 : (NODE)->user_conv_p ? cr_user \
159 static struct obstack conversion_obstack;
160 static bool conversion_obstack_initialized;
161 struct rejection_reason;
163 static struct z_candidate * tourney (struct z_candidate *, tsubst_flags_t);
164 static int equal_functions (tree, tree);
165 static int joust (struct z_candidate *, struct z_candidate *, bool,
167 static int compare_ics (conversion *, conversion *);
168 static tree build_over_call (struct z_candidate *, int, tsubst_flags_t);
169 static tree build_java_interface_fn_ref (tree, tree);
170 #define convert_like(CONV, EXPR, COMPLAIN) \
171 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
172 /*issue_conversion_warnings=*/true, \
173 /*c_cast_p=*/false, (COMPLAIN))
174 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
175 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
176 /*issue_conversion_warnings=*/true, \
177 /*c_cast_p=*/false, (COMPLAIN))
178 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
179 bool, tsubst_flags_t);
180 static void op_error (location_t, enum tree_code, enum tree_code, tree,
182 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int,
184 static void print_z_candidate (location_t, const char *, struct z_candidate *);
185 static void print_z_candidates (location_t, struct z_candidate *);
186 static tree build_this (tree);
187 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
188 static bool any_strictly_viable (struct z_candidate *);
189 static struct z_candidate *add_template_candidate
190 (struct z_candidate **, tree, tree, tree, tree, const vec<tree, va_gc> *,
191 tree, tree, tree, int, unification_kind_t, tsubst_flags_t);
192 static struct z_candidate *add_template_candidate_real
193 (struct z_candidate **, tree, tree, tree, tree, const vec<tree, va_gc> *,
194 tree, tree, tree, int, tree, unification_kind_t, tsubst_flags_t);
195 static struct z_candidate *add_template_conv_candidate
196 (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *,
197 tree, tree, tree, tsubst_flags_t);
198 static void add_builtin_candidates
199 (struct z_candidate **, enum tree_code, enum tree_code,
200 tree, tree *, int, tsubst_flags_t);
201 static void add_builtin_candidate
202 (struct z_candidate **, enum tree_code, enum tree_code,
203 tree, tree, tree, tree *, tree *, int, tsubst_flags_t);
204 static bool is_complete (tree);
205 static void build_builtin_candidate
206 (struct z_candidate **, tree, tree, tree, tree *, tree *,
207 int, tsubst_flags_t);
208 static struct z_candidate *add_conv_candidate
209 (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *, tree,
210 tree, tsubst_flags_t);
211 static struct z_candidate *add_function_candidate
212 (struct z_candidate **, tree, tree, tree, const vec<tree, va_gc> *, tree,
213 tree, int, tsubst_flags_t);
214 static conversion *implicit_conversion (tree, tree, tree, bool, int,
216 static conversion *standard_conversion (tree, tree, tree, bool, int);
217 static conversion *reference_binding (tree, tree, tree, bool, int,
219 static conversion *build_conv (conversion_kind, tree, conversion *);
220 static conversion *build_list_conv (tree, tree, int, tsubst_flags_t);
221 static conversion *next_conversion (conversion *);
222 static bool is_subseq (conversion *, conversion *);
223 static conversion *maybe_handle_ref_bind (conversion **);
224 static void maybe_handle_implicit_object (conversion **);
225 static struct z_candidate *add_candidate
226 (struct z_candidate **, tree, tree, const vec<tree, va_gc> *, size_t,
227 conversion **, tree, tree, int, struct rejection_reason *, int);
228 static tree source_type (conversion *);
229 static void add_warning (struct z_candidate *, struct z_candidate *);
230 static bool reference_compatible_p (tree, tree);
231 static conversion *direct_reference_binding (tree, conversion *);
232 static bool promoted_arithmetic_type_p (tree);
233 static conversion *conditional_conversion (tree, tree, tsubst_flags_t);
234 static char *name_as_c_string (tree, tree, bool *);
235 static tree prep_operand (tree);
236 static void add_candidates (tree, tree, const vec<tree, va_gc> *, tree, tree,
237 bool, tree, tree, int, struct z_candidate **,
239 static conversion *merge_conversion_sequences (conversion *, conversion *);
240 static tree build_temp (tree, tree, int, diagnostic_t *, tsubst_flags_t);
242 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
243 NAME can take many forms... */
246 check_dtor_name (tree basetype, tree name)
248 /* Just accept something we've already complained about. */
249 if (name == error_mark_node)
252 if (TREE_CODE (name) == TYPE_DECL)
253 name = TREE_TYPE (name);
254 else if (TYPE_P (name))
256 else if (identifier_p (name))
258 if ((MAYBE_CLASS_TYPE_P (basetype)
259 && name == constructor_name (basetype))
260 || (TREE_CODE (basetype) == ENUMERAL_TYPE
261 && name == TYPE_IDENTIFIER (basetype)))
264 name = get_type_value (name);
270 template <class T> struct S { ~S(); };
274 NAME will be a class template. */
275 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
279 if (!name || name == error_mark_node)
281 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
284 /* We want the address of a function or method. We avoid creating a
285 pointer-to-member function. */
288 build_addr_func (tree function, tsubst_flags_t complain)
290 tree type = TREE_TYPE (function);
292 /* We have to do these by hand to avoid real pointer to member
294 if (TREE_CODE (type) == METHOD_TYPE)
296 if (TREE_CODE (function) == OFFSET_REF)
298 tree object = build_address (TREE_OPERAND (function, 0));
299 return get_member_function_from_ptrfunc (&object,
300 TREE_OPERAND (function, 1),
303 function = build_address (function);
306 function = decay_conversion (function, complain);
311 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
312 POINTER_TYPE to those. Note, pointer to member function types
313 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
314 two variants. build_call_a is the primitive taking an array of
315 arguments, while build_call_n is a wrapper that handles varargs. */
318 build_call_n (tree function, int n, ...)
321 return build_call_a (function, 0, NULL);
324 tree *argarray = XALLOCAVEC (tree, n);
329 for (i = 0; i < n; i++)
330 argarray[i] = va_arg (ap, tree);
332 return build_call_a (function, n, argarray);
336 /* Update various flags in cfun and the call itself based on what is being
337 called. Split out of build_call_a so that bot_manip can use it too. */
340 set_flags_from_callee (tree call)
343 tree decl = get_callee_fndecl (call);
345 /* We check both the decl and the type; a function may be known not to
346 throw without being declared throw(). */
347 nothrow = decl && TREE_NOTHROW (decl);
348 if (CALL_EXPR_FN (call))
349 nothrow |= TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (call))));
350 else if (internal_fn_flags (CALL_EXPR_IFN (call)) & ECF_NOTHROW)
353 if (!nothrow && at_function_scope_p () && cfun && cp_function_chain)
354 cp_function_chain->can_throw = 1;
356 if (decl && TREE_THIS_VOLATILE (decl) && cfun && cp_function_chain)
357 current_function_returns_abnormally = 1;
359 TREE_NOTHROW (call) = nothrow;
363 build_call_a (tree function, int n, tree *argarray)
370 function = build_addr_func (function, tf_warning_or_error);
372 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
373 fntype = TREE_TYPE (TREE_TYPE (function));
374 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
375 || TREE_CODE (fntype) == METHOD_TYPE);
376 result_type = TREE_TYPE (fntype);
377 /* An rvalue has no cv-qualifiers. */
378 if (SCALAR_TYPE_P (result_type) || VOID_TYPE_P (result_type))
379 result_type = cv_unqualified (result_type);
381 function = build_call_array_loc (input_location,
382 result_type, function, n, argarray);
383 set_flags_from_callee (function);
385 decl = get_callee_fndecl (function);
387 if (decl && !TREE_USED (decl))
389 /* We invoke build_call directly for several library
390 functions. These may have been declared normally if
391 we're building libgcc, so we can't just check
393 gcc_assert (DECL_ARTIFICIAL (decl)
394 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
399 require_complete_eh_spec_types (fntype, decl);
401 TREE_HAS_CONSTRUCTOR (function) = (decl && DECL_CONSTRUCTOR_P (decl));
403 /* Don't pass empty class objects by value. This is useful
404 for tags in STL, which are used to control overload resolution.
405 We don't need to handle other cases of copying empty classes. */
406 if (! decl || ! DECL_BUILT_IN (decl))
407 for (i = 0; i < n; i++)
409 tree arg = CALL_EXPR_ARG (function, i);
410 if (is_empty_class (TREE_TYPE (arg))
411 && ! TREE_ADDRESSABLE (TREE_TYPE (arg)))
413 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (arg));
414 arg = build2 (COMPOUND_EXPR, TREE_TYPE (t), arg, t);
415 CALL_EXPR_ARG (function, i) = arg;
422 /* Build something of the form ptr->method (args)
423 or object.method (args). This can also build
424 calls to constructors, and find friends.
426 Member functions always take their class variable
429 INSTANCE is a class instance.
431 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
433 PARMS help to figure out what that NAME really refers to.
435 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
436 down to the real instance type to use for access checking. We need this
437 information to get protected accesses correct.
439 FLAGS is the logical disjunction of zero or more LOOKUP_
440 flags. See cp-tree.h for more info.
442 If this is all OK, calls build_function_call with the resolved
445 This function must also handle being called to perform
446 initialization, promotion/coercion of arguments, and
447 instantiation of default parameters.
449 Note that NAME may refer to an instance variable name. If
450 `operator()()' is defined for the type of that field, then we return
453 /* New overloading code. */
455 typedef struct z_candidate z_candidate;
457 typedef struct candidate_warning candidate_warning;
458 struct candidate_warning {
460 candidate_warning *next;
463 /* Information for providing diagnostics about why overloading failed. */
465 enum rejection_reason_code {
468 rr_explicit_conversion,
469 rr_template_conversion,
471 rr_bad_arg_conversion,
472 rr_template_unification,
476 struct conversion_info {
477 /* The index of the argument, 0-based. */
479 /* The actual argument or its type. */
481 /* The type of the parameter. */
485 struct rejection_reason {
486 enum rejection_reason_code code;
488 /* Information about an arity mismatch. */
490 /* The expected number of arguments. */
492 /* The actual number of arguments in the call. */
494 /* Whether the call was a varargs call. */
497 /* Information about an argument conversion mismatch. */
498 struct conversion_info conversion;
499 /* Same, but for bad argument conversions. */
500 struct conversion_info bad_conversion;
501 /* Information about template unification failures. These are the
502 parameters passed to fn_type_unification. */
510 unification_kind_t strict;
512 } template_unification;
513 /* Information about template instantiation failures. These are the
514 parameters passed to instantiate_template. */
518 } template_instantiation;
523 /* The FUNCTION_DECL that will be called if this candidate is
524 selected by overload resolution. */
526 /* If not NULL_TREE, the first argument to use when calling this
529 /* The rest of the arguments to use when calling this function. If
530 there are no further arguments this may be NULL or it may be an
532 const vec<tree, va_gc> *args;
533 /* The implicit conversion sequences for each of the arguments to
536 /* The number of implicit conversion sequences. */
538 /* If FN is a user-defined conversion, the standard conversion
539 sequence from the type returned by FN to the desired destination
541 conversion *second_conv;
542 struct rejection_reason *reason;
543 /* If FN is a member function, the binfo indicating the path used to
544 qualify the name of FN at the call site. This path is used to
545 determine whether or not FN is accessible if it is selected by
546 overload resolution. The DECL_CONTEXT of FN will always be a
547 (possibly improper) base of this binfo. */
549 /* If FN is a non-static member function, the binfo indicating the
550 subobject to which the `this' pointer should be converted if FN
551 is selected by overload resolution. The type pointed to by
552 the `this' pointer must correspond to the most derived class
553 indicated by the CONVERSION_PATH. */
554 tree conversion_path;
557 candidate_warning *warnings;
561 /* The flags active in add_candidate. */
565 /* Returns true iff T is a null pointer constant in the sense of
569 null_ptr_cst_p (tree t)
573 A null pointer constant is an integral constant expression
574 (_expr.const_) rvalue of integer type that evaluates to zero or
575 an rvalue of type std::nullptr_t. */
576 if (NULLPTR_TYPE_P (TREE_TYPE (t)))
578 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
580 /* Core issue 903 says only literal 0 is a null pointer constant. */
581 if (cxx_dialect < cxx11)
582 t = fold_non_dependent_expr (t);
584 if (integer_zerop (t) && !TREE_OVERFLOW (t))
590 /* Returns true iff T is a null member pointer value (4.11). */
593 null_member_pointer_value_p (tree t)
595 tree type = TREE_TYPE (t);
598 else if (TYPE_PTRMEMFUNC_P (type))
599 return (TREE_CODE (t) == CONSTRUCTOR
600 && integer_zerop (CONSTRUCTOR_ELT (t, 0)->value));
601 else if (TYPE_PTRDATAMEM_P (type))
602 return integer_all_onesp (t);
607 /* Returns nonzero if PARMLIST consists of only default parms,
608 ellipsis, and/or undeduced parameter packs. */
611 sufficient_parms_p (const_tree parmlist)
613 for (; parmlist && parmlist != void_list_node;
614 parmlist = TREE_CHAIN (parmlist))
615 if (!TREE_PURPOSE (parmlist)
616 && !PACK_EXPANSION_P (TREE_VALUE (parmlist)))
621 /* Allocate N bytes of memory from the conversion obstack. The memory
622 is zeroed before being returned. */
625 conversion_obstack_alloc (size_t n)
628 if (!conversion_obstack_initialized)
630 gcc_obstack_init (&conversion_obstack);
631 conversion_obstack_initialized = true;
633 p = obstack_alloc (&conversion_obstack, n);
638 /* Allocate rejection reasons. */
640 static struct rejection_reason *
641 alloc_rejection (enum rejection_reason_code code)
643 struct rejection_reason *p;
644 p = (struct rejection_reason *) conversion_obstack_alloc (sizeof *p);
649 static struct rejection_reason *
650 arity_rejection (tree first_arg, int expected, int actual)
652 struct rejection_reason *r = alloc_rejection (rr_arity);
653 int adjust = first_arg != NULL_TREE;
654 r->u.arity.expected = expected - adjust;
655 r->u.arity.actual = actual - adjust;
659 static struct rejection_reason *
660 arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
662 struct rejection_reason *r = alloc_rejection (rr_arg_conversion);
663 int adjust = first_arg != NULL_TREE;
664 r->u.conversion.n_arg = n_arg - adjust;
665 r->u.conversion.from = from;
666 r->u.conversion.to_type = to;
670 static struct rejection_reason *
671 bad_arg_conversion_rejection (tree first_arg, int n_arg, tree from, tree to)
673 struct rejection_reason *r = alloc_rejection (rr_bad_arg_conversion);
674 int adjust = first_arg != NULL_TREE;
675 r->u.bad_conversion.n_arg = n_arg - adjust;
676 r->u.bad_conversion.from = from;
677 r->u.bad_conversion.to_type = to;
681 static struct rejection_reason *
682 explicit_conversion_rejection (tree from, tree to)
684 struct rejection_reason *r = alloc_rejection (rr_explicit_conversion);
685 r->u.conversion.n_arg = 0;
686 r->u.conversion.from = from;
687 r->u.conversion.to_type = to;
691 static struct rejection_reason *
692 template_conversion_rejection (tree from, tree to)
694 struct rejection_reason *r = alloc_rejection (rr_template_conversion);
695 r->u.conversion.n_arg = 0;
696 r->u.conversion.from = from;
697 r->u.conversion.to_type = to;
701 static struct rejection_reason *
702 template_unification_rejection (tree tmpl, tree explicit_targs, tree targs,
703 const tree *args, unsigned int nargs,
704 tree return_type, unification_kind_t strict,
707 size_t args_n_bytes = sizeof (*args) * nargs;
708 tree *args1 = (tree *) conversion_obstack_alloc (args_n_bytes);
709 struct rejection_reason *r = alloc_rejection (rr_template_unification);
710 r->u.template_unification.tmpl = tmpl;
711 r->u.template_unification.explicit_targs = explicit_targs;
712 r->u.template_unification.num_targs = TREE_VEC_LENGTH (targs);
713 /* Copy args to our own storage. */
714 memcpy (args1, args, args_n_bytes);
715 r->u.template_unification.args = args1;
716 r->u.template_unification.nargs = nargs;
717 r->u.template_unification.return_type = return_type;
718 r->u.template_unification.strict = strict;
719 r->u.template_unification.flags = flags;
723 static struct rejection_reason *
724 template_unification_error_rejection (void)
726 return alloc_rejection (rr_template_unification);
729 static struct rejection_reason *
730 invalid_copy_with_fn_template_rejection (void)
732 struct rejection_reason *r = alloc_rejection (rr_invalid_copy);
736 /* Dynamically allocate a conversion. */
739 alloc_conversion (conversion_kind kind)
742 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
747 #ifdef ENABLE_CHECKING
749 /* Make sure that all memory on the conversion obstack has been
753 validate_conversion_obstack (void)
755 if (conversion_obstack_initialized)
756 gcc_assert ((obstack_next_free (&conversion_obstack)
757 == obstack_base (&conversion_obstack)));
760 #endif /* ENABLE_CHECKING */
762 /* Dynamically allocate an array of N conversions. */
765 alloc_conversions (size_t n)
767 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
771 build_conv (conversion_kind code, tree type, conversion *from)
774 conversion_rank rank = CONVERSION_RANK (from);
776 /* Note that the caller is responsible for filling in t->cand for
777 user-defined conversions. */
778 t = alloc_conversion (code);
801 t->user_conv_p = (code == ck_user || from->user_conv_p);
802 t->bad_p = from->bad_p;
807 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
808 specialization of std::initializer_list<T>, if such a conversion is
812 build_list_conv (tree type, tree ctor, int flags, tsubst_flags_t complain)
814 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (type), 0);
815 unsigned len = CONSTRUCTOR_NELTS (ctor);
816 conversion **subconvs = alloc_conversions (len);
821 /* Within a list-initialization we can have more user-defined
823 flags &= ~LOOKUP_NO_CONVERSION;
824 /* But no narrowing conversions. */
825 flags |= LOOKUP_NO_NARROWING;
827 /* Can't make an array of these types. */
828 if (TREE_CODE (elttype) == REFERENCE_TYPE
829 || TREE_CODE (elttype) == FUNCTION_TYPE
830 || VOID_TYPE_P (elttype))
833 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
836 = implicit_conversion (elttype, TREE_TYPE (val), val,
837 false, flags, complain);
844 t = alloc_conversion (ck_list);
846 t->u.list = subconvs;
849 for (i = 0; i < len; ++i)
851 conversion *sub = subconvs[i];
852 if (sub->rank > t->rank)
854 if (sub->user_conv_p)
855 t->user_conv_p = true;
863 /* Return the next conversion of the conversion chain (if applicable),
864 or NULL otherwise. Please use this function instead of directly
865 accessing fields of struct conversion. */
868 next_conversion (conversion *conv)
871 || conv->kind == ck_identity
872 || conv->kind == ck_ambig
873 || conv->kind == ck_list)
878 /* Subroutine of build_aggr_conv: check whether CTOR, a braced-init-list,
879 is a valid aggregate initializer for array type ATYPE. */
882 can_convert_array (tree atype, tree ctor, int flags, tsubst_flags_t complain)
885 tree elttype = TREE_TYPE (atype);
886 for (i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
888 tree val = CONSTRUCTOR_ELT (ctor, i)->value;
890 if (TREE_CODE (elttype) == ARRAY_TYPE
891 && TREE_CODE (val) == CONSTRUCTOR)
892 ok = can_convert_array (elttype, val, flags, complain);
894 ok = can_convert_arg (elttype, TREE_TYPE (val), val, flags,
902 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
903 aggregate class, if such a conversion is possible. */
906 build_aggr_conv (tree type, tree ctor, int flags, tsubst_flags_t complain)
908 unsigned HOST_WIDE_INT i = 0;
910 tree field = next_initializable_field (TYPE_FIELDS (type));
911 tree empty_ctor = NULL_TREE;
913 /* We already called reshape_init in implicit_conversion. */
915 /* The conversions within the init-list aren't affected by the enclosing
916 context; they're always simple copy-initialization. */
917 flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING;
919 for (; field; field = next_initializable_field (DECL_CHAIN (field)))
921 tree ftype = TREE_TYPE (field);
925 if (i < CONSTRUCTOR_NELTS (ctor))
926 val = CONSTRUCTOR_ELT (ctor, i)->value;
927 else if (TREE_CODE (ftype) == REFERENCE_TYPE)
928 /* Value-initialization of reference is ill-formed. */
932 if (empty_ctor == NULL_TREE)
933 empty_ctor = build_constructor (init_list_type_node, NULL);
938 if (TREE_CODE (ftype) == ARRAY_TYPE
939 && TREE_CODE (val) == CONSTRUCTOR)
940 ok = can_convert_array (ftype, val, flags, complain);
942 ok = can_convert_arg (ftype, TREE_TYPE (val), val, flags,
948 if (TREE_CODE (type) == UNION_TYPE)
952 if (i < CONSTRUCTOR_NELTS (ctor))
955 c = alloc_conversion (ck_aggr);
958 c->user_conv_p = true;
959 c->check_narrowing = true;
964 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
965 array type, if such a conversion is possible. */
968 build_array_conv (tree type, tree ctor, int flags, tsubst_flags_t complain)
971 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
972 tree elttype = TREE_TYPE (type);
977 enum conversion_rank rank = cr_exact;
979 /* We might need to propagate the size from the element to the array. */
980 complete_type (type);
982 if (TYPE_DOMAIN (type)
983 && !variably_modified_type_p (TYPE_DOMAIN (type), NULL_TREE))
985 unsigned HOST_WIDE_INT alen = tree_to_uhwi (array_type_nelts_top (type));
990 flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING;
992 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
995 = implicit_conversion (elttype, TREE_TYPE (val), val,
996 false, flags, complain);
1000 if (sub->rank > rank)
1002 if (sub->user_conv_p)
1008 c = alloc_conversion (ck_aggr);
1011 c->user_conv_p = user;
1017 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
1018 complex type, if such a conversion is possible. */
1021 build_complex_conv (tree type, tree ctor, int flags,
1022 tsubst_flags_t complain)
1025 unsigned HOST_WIDE_INT len = CONSTRUCTOR_NELTS (ctor);
1026 tree elttype = TREE_TYPE (type);
1031 enum conversion_rank rank = cr_exact;
1036 flags = LOOKUP_IMPLICIT|LOOKUP_NO_NARROWING;
1038 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (ctor), i, val)
1041 = implicit_conversion (elttype, TREE_TYPE (val), val,
1042 false, flags, complain);
1046 if (sub->rank > rank)
1048 if (sub->user_conv_p)
1054 c = alloc_conversion (ck_aggr);
1057 c->user_conv_p = user;
1063 /* Build a representation of the identity conversion from EXPR to
1064 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
1067 build_identity_conv (tree type, tree expr)
1071 c = alloc_conversion (ck_identity);
1078 /* Converting from EXPR to TYPE was ambiguous in the sense that there
1079 were multiple user-defined conversions to accomplish the job.
1080 Build a conversion that indicates that ambiguity. */
1083 build_ambiguous_conv (tree type, tree expr)
1087 c = alloc_conversion (ck_ambig);
1095 strip_top_quals (tree t)
1097 if (TREE_CODE (t) == ARRAY_TYPE)
1099 return cp_build_qualified_type (t, 0);
1102 /* Returns the standard conversion path (see [conv]) from type FROM to type
1103 TO, if any. For proper handling of null pointer constants, you must
1104 also pass the expression EXPR to convert from. If C_CAST_P is true,
1105 this conversion is coming from a C-style cast. */
1108 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
1111 enum tree_code fcode, tcode;
1113 bool fromref = false;
1116 to = non_reference (to);
1117 if (TREE_CODE (from) == REFERENCE_TYPE)
1120 from = TREE_TYPE (from);
1123 to = strip_top_quals (to);
1124 from = strip_top_quals (from);
1126 if (expr && type_unknown_p (expr))
1128 if (TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
1130 tsubst_flags_t tflags = tf_conv;
1131 expr = instantiate_type (to, expr, tflags);
1132 if (expr == error_mark_node)
1134 from = TREE_TYPE (expr);
1136 else if (TREE_CODE (to) == BOOLEAN_TYPE)
1138 /* Necessary for eg, TEMPLATE_ID_EXPRs (c++/50961). */
1139 expr = resolve_nondeduced_context (expr);
1140 from = TREE_TYPE (expr);
1144 fcode = TREE_CODE (from);
1145 tcode = TREE_CODE (to);
1147 conv = build_identity_conv (from, expr);
1148 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
1150 from = type_decays_to (from);
1151 fcode = TREE_CODE (from);
1152 conv = build_conv (ck_lvalue, from, conv);
1154 else if (fromref || (expr && lvalue_p (expr)))
1159 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
1162 from = strip_top_quals (bitfield_type);
1163 fcode = TREE_CODE (from);
1166 conv = build_conv (ck_rvalue, from, conv);
1167 if (flags & LOOKUP_PREFER_RVALUE)
1168 conv->rvaluedness_matches_p = true;
1171 /* Allow conversion between `__complex__' data types. */
1172 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
1174 /* The standard conversion sequence to convert FROM to TO is
1175 the standard conversion sequence to perform componentwise
1177 conversion *part_conv = standard_conversion
1178 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
1182 conv = build_conv (part_conv->kind, to, conv);
1183 conv->rank = part_conv->rank;
1191 if (same_type_p (from, to))
1193 if (CLASS_TYPE_P (to) && conv->kind == ck_rvalue)
1194 conv->type = qualified_to;
1199 A null pointer constant can be converted to a pointer type; ... A
1200 null pointer constant of integral type can be converted to an
1201 rvalue of type std::nullptr_t. */
1202 if ((tcode == POINTER_TYPE || TYPE_PTRMEM_P (to)
1203 || NULLPTR_TYPE_P (to))
1204 && ((expr && null_ptr_cst_p (expr))
1205 || NULLPTR_TYPE_P (from)))
1206 conv = build_conv (ck_std, to, conv);
1207 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
1208 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
1210 /* For backwards brain damage compatibility, allow interconversion of
1211 pointers and integers with a pedwarn. */
1212 conv = build_conv (ck_std, to, conv);
1215 else if (UNSCOPED_ENUM_P (to) && fcode == INTEGER_TYPE)
1217 /* For backwards brain damage compatibility, allow interconversion of
1218 enums and integers with a pedwarn. */
1219 conv = build_conv (ck_std, to, conv);
1222 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
1223 || (TYPE_PTRDATAMEM_P (to) && TYPE_PTRDATAMEM_P (from)))
1228 if (tcode == POINTER_TYPE
1229 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
1232 else if (VOID_TYPE_P (TREE_TYPE (to))
1233 && !TYPE_PTRDATAMEM_P (from)
1234 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
1236 tree nfrom = TREE_TYPE (from);
1237 /* Don't try to apply restrict to void. */
1238 int quals = cp_type_quals (nfrom) & ~TYPE_QUAL_RESTRICT;
1239 from = build_pointer_type
1240 (cp_build_qualified_type (void_type_node, quals));
1241 conv = build_conv (ck_ptr, from, conv);
1243 else if (TYPE_PTRDATAMEM_P (from))
1245 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
1246 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
1248 if (DERIVED_FROM_P (fbase, tbase)
1249 && (same_type_ignoring_top_level_qualifiers_p
1250 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
1251 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
1253 from = build_ptrmem_type (tbase,
1254 TYPE_PTRMEM_POINTED_TO_TYPE (from));
1255 conv = build_conv (ck_pmem, from, conv);
1257 else if (!same_type_p (fbase, tbase))
1260 else if (CLASS_TYPE_P (TREE_TYPE (from))
1261 && CLASS_TYPE_P (TREE_TYPE (to))
1264 An rvalue of type "pointer to cv D," where D is a
1265 class type, can be converted to an rvalue of type
1266 "pointer to cv B," where B is a base class (clause
1267 _class.derived_) of D. If B is an inaccessible
1268 (clause _class.access_) or ambiguous
1269 (_class.member.lookup_) base class of D, a program
1270 that necessitates this conversion is ill-formed.
1271 Therefore, we use DERIVED_FROM_P, and do not check
1272 access or uniqueness. */
1273 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
1276 cp_build_qualified_type (TREE_TYPE (to),
1277 cp_type_quals (TREE_TYPE (from)));
1278 from = build_pointer_type (from);
1279 conv = build_conv (ck_ptr, from, conv);
1280 conv->base_p = true;
1283 if (tcode == POINTER_TYPE)
1285 to_pointee = TREE_TYPE (to);
1286 from_pointee = TREE_TYPE (from);
1290 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
1291 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
1294 if (same_type_p (from, to))
1296 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
1297 /* In a C-style cast, we ignore CV-qualification because we
1298 are allowed to perform a static_cast followed by a
1300 conv = build_conv (ck_qual, to, conv);
1301 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
1302 conv = build_conv (ck_qual, to, conv);
1303 else if (expr && string_conv_p (to, expr, 0))
1304 /* converting from string constant to char *. */
1305 conv = build_conv (ck_qual, to, conv);
1306 /* Allow conversions among compatible ObjC pointer types (base
1307 conversions have been already handled above). */
1308 else if (c_dialect_objc ()
1309 && objc_compare_types (to, from, -4, NULL_TREE))
1310 conv = build_conv (ck_ptr, to, conv);
1311 else if (ptr_reasonably_similar (to_pointee, from_pointee))
1313 conv = build_conv (ck_ptr, to, conv);
1321 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
1323 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
1324 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
1325 tree fbase = class_of_this_parm (fromfn);
1326 tree tbase = class_of_this_parm (tofn);
1328 if (!DERIVED_FROM_P (fbase, tbase)
1329 || !same_type_p (static_fn_type (fromfn),
1330 static_fn_type (tofn)))
1333 from = build_memfn_type (fromfn,
1335 cp_type_quals (tbase),
1336 type_memfn_rqual (tofn));
1337 from = build_ptrmemfunc_type (build_pointer_type (from));
1338 conv = build_conv (ck_pmem, from, conv);
1339 conv->base_p = true;
1341 else if (tcode == BOOLEAN_TYPE)
1345 A prvalue of arithmetic, unscoped enumeration, pointer, or pointer
1346 to member type can be converted to a prvalue of type bool. ...
1347 For direct-initialization (8.5 [dcl.init]), a prvalue of type
1348 std::nullptr_t can be converted to a prvalue of type bool; */
1349 if (ARITHMETIC_TYPE_P (from)
1350 || UNSCOPED_ENUM_P (from)
1351 || fcode == POINTER_TYPE
1352 || TYPE_PTRMEM_P (from)
1353 || NULLPTR_TYPE_P (from))
1355 conv = build_conv (ck_std, to, conv);
1356 if (fcode == POINTER_TYPE
1357 || TYPE_PTRDATAMEM_P (from)
1358 || (TYPE_PTRMEMFUNC_P (from)
1359 && conv->rank < cr_pbool)
1360 || NULLPTR_TYPE_P (from))
1361 conv->rank = cr_pbool;
1362 if (NULLPTR_TYPE_P (from) && (flags & LOOKUP_ONLYCONVERTING))
1369 /* We don't check for ENUMERAL_TYPE here because there are no standard
1370 conversions to enum type. */
1371 /* As an extension, allow conversion to complex type. */
1372 else if (ARITHMETIC_TYPE_P (to))
1374 if (! (INTEGRAL_CODE_P (fcode)
1375 || (fcode == REAL_TYPE && !(flags & LOOKUP_NO_NON_INTEGRAL)))
1376 || SCOPED_ENUM_P (from))
1378 conv = build_conv (ck_std, to, conv);
1380 /* Give this a better rank if it's a promotion. */
1381 if (same_type_p (to, type_promotes_to (from))
1382 && next_conversion (conv)->rank <= cr_promotion)
1383 conv->rank = cr_promotion;
1385 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
1386 && vector_types_convertible_p (from, to, false))
1387 return build_conv (ck_std, to, conv);
1388 else if (MAYBE_CLASS_TYPE_P (to) && MAYBE_CLASS_TYPE_P (from)
1389 && is_properly_derived_from (from, to))
1391 if (conv->kind == ck_rvalue)
1392 conv = next_conversion (conv);
1393 conv = build_conv (ck_base, to, conv);
1394 /* The derived-to-base conversion indicates the initialization
1395 of a parameter with base type from an object of a derived
1396 type. A temporary object is created to hold the result of
1397 the conversion unless we're binding directly to a reference. */
1398 conv->need_temporary_p = !(flags & LOOKUP_NO_TEMP_BIND);
1403 if (flags & LOOKUP_NO_NARROWING)
1404 conv->check_narrowing = true;
1409 /* Returns nonzero if T1 is reference-related to T2. */
1412 reference_related_p (tree t1, tree t2)
1414 if (t1 == error_mark_node || t2 == error_mark_node)
1417 t1 = TYPE_MAIN_VARIANT (t1);
1418 t2 = TYPE_MAIN_VARIANT (t2);
1422 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
1423 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
1425 return (same_type_p (t1, t2)
1426 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
1427 && DERIVED_FROM_P (t1, t2)));
1430 /* Returns nonzero if T1 is reference-compatible with T2. */
1433 reference_compatible_p (tree t1, tree t2)
1437 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
1438 reference-related to T2 and cv1 is the same cv-qualification as,
1439 or greater cv-qualification than, cv2. */
1440 return (reference_related_p (t1, t2)
1441 && at_least_as_qualified_p (t1, t2));
1444 /* A reference of the indicated TYPE is being bound directly to the
1445 expression represented by the implicit conversion sequence CONV.
1446 Return a conversion sequence for this binding. */
1449 direct_reference_binding (tree type, conversion *conv)
1453 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1454 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1456 t = TREE_TYPE (type);
1460 When a parameter of reference type binds directly
1461 (_dcl.init.ref_) to an argument expression, the implicit
1462 conversion sequence is the identity conversion, unless the
1463 argument expression has a type that is a derived class of the
1464 parameter type, in which case the implicit conversion sequence is
1465 a derived-to-base Conversion.
1467 If the parameter binds directly to the result of applying a
1468 conversion function to the argument expression, the implicit
1469 conversion sequence is a user-defined conversion sequence
1470 (_over.ics.user_), with the second standard conversion sequence
1471 either an identity conversion or, if the conversion function
1472 returns an entity of a type that is a derived class of the
1473 parameter type, a derived-to-base conversion. */
1474 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1476 /* Represent the derived-to-base conversion. */
1477 conv = build_conv (ck_base, t, conv);
1478 /* We will actually be binding to the base-class subobject in
1479 the derived class, so we mark this conversion appropriately.
1480 That way, convert_like knows not to generate a temporary. */
1481 conv->need_temporary_p = false;
1483 return build_conv (ck_ref_bind, type, conv);
1486 /* Returns the conversion path from type FROM to reference type TO for
1487 purposes of reference binding. For lvalue binding, either pass a
1488 reference type to FROM or an lvalue expression to EXPR. If the
1489 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1490 the conversion returned. If C_CAST_P is true, this
1491 conversion is coming from a C-style cast. */
1494 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags,
1495 tsubst_flags_t complain)
1497 conversion *conv = NULL;
1498 tree to = TREE_TYPE (rto);
1503 cp_lvalue_kind gl_kind;
1506 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1508 expr = instantiate_type (to, expr, tf_none);
1509 if (expr == error_mark_node)
1511 from = TREE_TYPE (expr);
1514 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1516 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
1517 /* DR 1288: Otherwise, if the initializer list has a single element
1518 of type E and ... [T's] referenced type is reference-related to E,
1519 the object or reference is initialized from that element... */
1520 if (CONSTRUCTOR_NELTS (expr) == 1)
1522 tree elt = CONSTRUCTOR_ELT (expr, 0)->value;
1523 if (error_operand_p (elt))
1525 tree etype = TREE_TYPE (elt);
1526 if (reference_related_p (to, etype))
1533 /* Otherwise, if T is a reference type, a prvalue temporary of the
1534 type referenced by T is copy-list-initialized or
1535 direct-list-initialized, depending on the kind of initialization
1536 for the reference, and the reference is bound to that temporary. */
1537 conv = implicit_conversion (to, from, expr, c_cast_p,
1538 flags|LOOKUP_NO_TEMP_BIND, complain);
1542 if (TREE_CODE (from) == REFERENCE_TYPE)
1544 from = TREE_TYPE (from);
1545 if (!TYPE_REF_IS_RVALUE (rfrom)
1546 || TREE_CODE (from) == FUNCTION_TYPE)
1547 gl_kind = clk_ordinary;
1549 gl_kind = clk_rvalueref;
1553 gl_kind = lvalue_kind (expr);
1554 if (gl_kind & clk_class)
1555 /* A class prvalue is not a glvalue. */
1560 is_lvalue = gl_kind && !(gl_kind & clk_rvalueref);
1563 if ((gl_kind & clk_bitfield) != 0)
1564 tfrom = unlowered_expr_type (expr);
1566 /* Figure out whether or not the types are reference-related and
1567 reference compatible. We have do do this after stripping
1568 references from FROM. */
1569 related_p = reference_related_p (to, tfrom);
1570 /* If this is a C cast, first convert to an appropriately qualified
1571 type, so that we can later do a const_cast to the desired type. */
1572 if (related_p && c_cast_p
1573 && !at_least_as_qualified_p (to, tfrom))
1574 to = cp_build_qualified_type (to, cp_type_quals (tfrom));
1575 compatible_p = reference_compatible_p (to, tfrom);
1577 /* Directly bind reference when target expression's type is compatible with
1578 the reference and expression is an lvalue. In DR391, the wording in
1579 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1580 const and rvalue references to rvalues of compatible class type.
1581 We should also do direct bindings for non-class xvalues. */
1584 || (!(flags & LOOKUP_NO_TEMP_BIND)
1585 && (CLASS_TYPE_P (from)
1586 || TREE_CODE (from) == ARRAY_TYPE))))
1590 If the initializer expression
1592 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1593 is reference-compatible with "cv2 T2,"
1595 the reference is bound directly to the initializer expression
1599 If the initializer expression is an rvalue, with T2 a class type,
1600 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1601 is bound to the object represented by the rvalue or to a sub-object
1602 within that object. */
1604 conv = build_identity_conv (tfrom, expr);
1605 conv = direct_reference_binding (rto, conv);
1607 if (flags & LOOKUP_PREFER_RVALUE)
1608 /* The top-level caller requested that we pretend that the lvalue
1609 be treated as an rvalue. */
1610 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1611 else if (TREE_CODE (rfrom) == REFERENCE_TYPE)
1612 /* Handle rvalue reference to function properly. */
1613 conv->rvaluedness_matches_p
1614 = (TYPE_REF_IS_RVALUE (rto) == TYPE_REF_IS_RVALUE (rfrom));
1616 conv->rvaluedness_matches_p
1617 = (TYPE_REF_IS_RVALUE (rto) == !is_lvalue);
1619 if ((gl_kind & clk_bitfield) != 0
1620 || ((gl_kind & clk_packed) != 0 && !TYPE_PACKED (to)))
1621 /* For the purposes of overload resolution, we ignore the fact
1622 this expression is a bitfield or packed field. (In particular,
1623 [over.ics.ref] says specifically that a function with a
1624 non-const reference parameter is viable even if the
1625 argument is a bitfield.)
1627 However, when we actually call the function we must create
1628 a temporary to which to bind the reference. If the
1629 reference is volatile, or isn't const, then we cannot make
1630 a temporary, so we just issue an error when the conversion
1632 conv->need_temporary_p = true;
1634 /* Don't allow binding of lvalues (other than function lvalues) to
1635 rvalue references. */
1636 if (is_lvalue && TYPE_REF_IS_RVALUE (rto)
1637 && TREE_CODE (to) != FUNCTION_TYPE
1638 && !(flags & LOOKUP_PREFER_RVALUE))
1641 /* Nor the reverse. */
1642 if (!is_lvalue && !TYPE_REF_IS_RVALUE (rto)
1643 && (!CP_TYPE_CONST_NON_VOLATILE_P (to)
1644 || (flags & LOOKUP_NO_RVAL_BIND))
1645 && TREE_CODE (to) != FUNCTION_TYPE)
1653 /* [class.conv.fct] A conversion function is never used to convert a
1654 (possibly cv-qualified) object to the (possibly cv-qualified) same
1655 object type (or a reference to it), to a (possibly cv-qualified) base
1656 class of that type (or a reference to it).... */
1657 else if (CLASS_TYPE_P (from) && !related_p
1658 && !(flags & LOOKUP_NO_CONVERSION))
1662 If the initializer expression
1664 -- has a class type (i.e., T2 is a class type) can be
1665 implicitly converted to an lvalue of type "cv3 T3," where
1666 "cv1 T1" is reference-compatible with "cv3 T3". (this
1667 conversion is selected by enumerating the applicable
1668 conversion functions (_over.match.ref_) and choosing the
1669 best one through overload resolution. (_over.match_).
1671 the reference is bound to the lvalue result of the conversion
1672 in the second case. */
1673 z_candidate *cand = build_user_type_conversion_1 (rto, expr, flags,
1676 return cand->second_conv;
1679 /* From this point on, we conceptually need temporaries, even if we
1680 elide them. Only the cases above are "direct bindings". */
1681 if (flags & LOOKUP_NO_TEMP_BIND)
1686 When a parameter of reference type is not bound directly to an
1687 argument expression, the conversion sequence is the one required
1688 to convert the argument expression to the underlying type of the
1689 reference according to _over.best.ics_. Conceptually, this
1690 conversion sequence corresponds to copy-initializing a temporary
1691 of the underlying type with the argument expression. Any
1692 difference in top-level cv-qualification is subsumed by the
1693 initialization itself and does not constitute a conversion. */
1697 Otherwise, the reference shall be an lvalue reference to a
1698 non-volatile const type, or the reference shall be an rvalue
1701 We try below to treat this as a bad conversion to improve diagnostics,
1702 but if TO is an incomplete class, we need to reject this conversion
1703 now to avoid unnecessary instantiation. */
1704 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto)
1705 && !COMPLETE_TYPE_P (to))
1708 /* We're generating a temporary now, but don't bind any more in the
1709 conversion (specifically, don't slice the temporary returned by a
1710 conversion operator). */
1711 flags |= LOOKUP_NO_TEMP_BIND;
1713 /* Core issue 899: When [copy-]initializing a temporary to be bound
1714 to the first parameter of a copy constructor (12.8) called with
1715 a single argument in the context of direct-initialization,
1716 explicit conversion functions are also considered.
1718 So don't set LOOKUP_ONLYCONVERTING in that case. */
1719 if (!(flags & LOOKUP_COPY_PARM))
1720 flags |= LOOKUP_ONLYCONVERTING;
1723 conv = implicit_conversion (to, from, expr, c_cast_p,
1728 if (conv->user_conv_p)
1730 /* If initializing the temporary used a conversion function,
1731 recalculate the second conversion sequence. */
1732 for (conversion *t = conv; t; t = next_conversion (t))
1733 if (t->kind == ck_user
1734 && DECL_CONV_FN_P (t->cand->fn))
1736 tree ftype = TREE_TYPE (TREE_TYPE (t->cand->fn));
1737 int sflags = (flags|LOOKUP_NO_CONVERSION)&~LOOKUP_NO_TEMP_BIND;
1738 conversion *new_second
1739 = reference_binding (rto, ftype, NULL_TREE, c_cast_p,
1743 return merge_conversion_sequences (t, new_second);
1747 conv = build_conv (ck_ref_bind, rto, conv);
1748 /* This reference binding, unlike those above, requires the
1749 creation of a temporary. */
1750 conv->need_temporary_p = true;
1751 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1755 Otherwise, the reference shall be an lvalue reference to a
1756 non-volatile const type, or the reference shall be an rvalue
1758 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1763 Otherwise, a temporary of type "cv1 T1" is created and
1764 initialized from the initializer expression using the rules for a
1765 non-reference copy initialization. If T1 is reference-related to
1766 T2, cv1 must be the same cv-qualification as, or greater
1767 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1768 if (related_p && !at_least_as_qualified_p (to, from))
1774 /* Returns the implicit conversion sequence (see [over.ics]) from type
1775 FROM to type TO. The optional expression EXPR may affect the
1776 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1777 true, this conversion is coming from a C-style cast. */
1780 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1781 int flags, tsubst_flags_t complain)
1785 if (from == error_mark_node || to == error_mark_node
1786 || expr == error_mark_node)
1789 /* Other flags only apply to the primary function in overload
1790 resolution, or after we've chosen one. */
1791 flags &= (LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION|LOOKUP_COPY_PARM
1792 |LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND|LOOKUP_PREFER_RVALUE
1793 |LOOKUP_NO_NARROWING|LOOKUP_PROTECT|LOOKUP_NO_NON_INTEGRAL);
1795 /* FIXME: actually we don't want warnings either, but we can't just
1796 have 'complain &= ~(tf_warning|tf_error)' because it would cause
1797 the regression of, eg, g++.old-deja/g++.benjamin/16077.C.
1798 We really ought not to issue that warning until we've committed
1799 to that conversion. */
1800 complain &= ~tf_error;
1802 /* Call reshape_init early to remove redundant braces. */
1803 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr)
1804 && CLASS_TYPE_P (to)
1805 && COMPLETE_TYPE_P (complete_type (to))
1806 && !CLASSTYPE_NON_AGGREGATE (to))
1808 expr = reshape_init (to, expr, complain);
1809 if (expr == error_mark_node)
1811 from = TREE_TYPE (expr);
1814 if (TREE_CODE (to) == REFERENCE_TYPE)
1815 conv = reference_binding (to, from, expr, c_cast_p, flags, complain);
1817 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1822 if (expr && BRACE_ENCLOSED_INITIALIZER_P (expr))
1824 if (is_std_init_list (to))
1825 return build_list_conv (to, expr, flags, complain);
1827 /* As an extension, allow list-initialization of _Complex. */
1828 if (TREE_CODE (to) == COMPLEX_TYPE)
1830 conv = build_complex_conv (to, expr, flags, complain);
1835 /* Allow conversion from an initializer-list with one element to a
1837 if (SCALAR_TYPE_P (to))
1839 int nelts = CONSTRUCTOR_NELTS (expr);
1843 elt = build_value_init (to, tf_none);
1844 else if (nelts == 1)
1845 elt = CONSTRUCTOR_ELT (expr, 0)->value;
1847 elt = error_mark_node;
1849 conv = implicit_conversion (to, TREE_TYPE (elt), elt,
1850 c_cast_p, flags, complain);
1853 conv->check_narrowing = true;
1854 if (BRACE_ENCLOSED_INITIALIZER_P (elt))
1855 /* Too many levels of braces, i.e. '{{1}}'. */
1860 else if (TREE_CODE (to) == ARRAY_TYPE)
1861 return build_array_conv (to, expr, flags, complain);
1864 if (expr != NULL_TREE
1865 && (MAYBE_CLASS_TYPE_P (from)
1866 || MAYBE_CLASS_TYPE_P (to))
1867 && (flags & LOOKUP_NO_CONVERSION) == 0)
1869 struct z_candidate *cand;
1871 if (CLASS_TYPE_P (to)
1872 && BRACE_ENCLOSED_INITIALIZER_P (expr)
1873 && !CLASSTYPE_NON_AGGREGATE (complete_type (to)))
1874 return build_aggr_conv (to, expr, flags, complain);
1876 cand = build_user_type_conversion_1 (to, expr, flags, complain);
1878 conv = cand->second_conv;
1880 /* We used to try to bind a reference to a temporary here, but that
1881 is now handled after the recursive call to this function at the end
1882 of reference_binding. */
1889 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1890 functions. ARGS will not be changed until a single candidate is
1893 static struct z_candidate *
1894 add_candidate (struct z_candidate **candidates,
1895 tree fn, tree first_arg, const vec<tree, va_gc> *args,
1896 size_t num_convs, conversion **convs,
1897 tree access_path, tree conversion_path,
1898 int viable, struct rejection_reason *reason,
1901 struct z_candidate *cand = (struct z_candidate *)
1902 conversion_obstack_alloc (sizeof (struct z_candidate));
1905 cand->first_arg = first_arg;
1907 cand->convs = convs;
1908 cand->num_convs = num_convs;
1909 cand->access_path = access_path;
1910 cand->conversion_path = conversion_path;
1911 cand->viable = viable;
1912 cand->reason = reason;
1913 cand->next = *candidates;
1914 cand->flags = flags;
1920 /* Return the number of remaining arguments in the parameter list
1921 beginning with ARG. */
1924 remaining_arguments (tree arg)
1928 for (n = 0; arg != NULL_TREE && arg != void_list_node;
1929 arg = TREE_CHAIN (arg))
1935 /* Create an overload candidate for the function or method FN called
1936 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1937 FLAGS is passed on to implicit_conversion.
1939 This does not change ARGS.
1941 CTYPE, if non-NULL, is the type we want to pretend this function
1942 comes from for purposes of overload resolution. */
1944 static struct z_candidate *
1945 add_function_candidate (struct z_candidate **candidates,
1946 tree fn, tree ctype, tree first_arg,
1947 const vec<tree, va_gc> *args, tree access_path,
1948 tree conversion_path, int flags,
1949 tsubst_flags_t complain)
1951 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1955 tree orig_first_arg = first_arg;
1958 struct rejection_reason *reason = NULL;
1960 /* At this point we should not see any functions which haven't been
1961 explicitly declared, except for friend functions which will have
1962 been found using argument dependent lookup. */
1963 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1965 /* The `this', `in_chrg' and VTT arguments to constructors are not
1966 considered in overload resolution. */
1967 if (DECL_CONSTRUCTOR_P (fn))
1969 parmlist = skip_artificial_parms_for (fn, parmlist);
1970 skip = num_artificial_parms_for (fn);
1971 if (skip > 0 && first_arg != NULL_TREE)
1974 first_arg = NULL_TREE;
1980 len = vec_safe_length (args) - skip + (first_arg != NULL_TREE ? 1 : 0);
1981 convs = alloc_conversions (len);
1983 /* 13.3.2 - Viable functions [over.match.viable]
1984 First, to be a viable function, a candidate function shall have enough
1985 parameters to agree in number with the arguments in the list.
1987 We need to check this first; otherwise, checking the ICSes might cause
1988 us to produce an ill-formed template instantiation. */
1990 parmnode = parmlist;
1991 for (i = 0; i < len; ++i)
1993 if (parmnode == NULL_TREE || parmnode == void_list_node)
1995 parmnode = TREE_CHAIN (parmnode);
1998 if ((i < len && parmnode)
1999 || !sufficient_parms_p (parmnode))
2001 int remaining = remaining_arguments (parmnode);
2003 reason = arity_rejection (first_arg, i + remaining, len);
2005 /* When looking for a function from a subobject from an implicit
2006 copy/move constructor/operator=, don't consider anything that takes (a
2007 reference to) an unrelated type. See c++/44909 and core 1092. */
2008 else if (parmlist && (flags & LOOKUP_DEFAULTED))
2010 if (DECL_CONSTRUCTOR_P (fn))
2012 else if (DECL_ASSIGNMENT_OPERATOR_P (fn)
2013 && DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR)
2019 parmnode = chain_index (i-1, parmlist);
2020 if (!reference_related_p (non_reference (TREE_VALUE (parmnode)),
2025 /* This only applies at the top level. */
2026 flags &= ~LOOKUP_DEFAULTED;
2032 /* Second, for F to be a viable function, there shall exist for each
2033 argument an implicit conversion sequence that converts that argument
2034 to the corresponding parameter of F. */
2036 parmnode = parmlist;
2038 for (i = 0; i < len; ++i)
2040 tree argtype, to_type;
2045 if (parmnode == void_list_node)
2048 if (i == 0 && first_arg != NULL_TREE)
2051 arg = CONST_CAST_TREE (
2052 (*args)[i + skip - (first_arg != NULL_TREE ? 1 : 0)]);
2053 argtype = lvalue_type (arg);
2055 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
2056 && ! DECL_CONSTRUCTOR_P (fn));
2060 tree parmtype = TREE_VALUE (parmnode);
2063 parmnode = TREE_CHAIN (parmnode);
2065 /* The type of the implicit object parameter ('this') for
2066 overload resolution is not always the same as for the
2067 function itself; conversion functions are considered to
2068 be members of the class being converted, and functions
2069 introduced by a using-declaration are considered to be
2070 members of the class that uses them.
2072 Since build_over_call ignores the ICS for the `this'
2073 parameter, we can just change the parm type. */
2074 if (ctype && is_this)
2076 parmtype = cp_build_qualified_type
2077 (ctype, cp_type_quals (TREE_TYPE (parmtype)));
2078 if (FUNCTION_REF_QUALIFIED (TREE_TYPE (fn)))
2080 /* If the function has a ref-qualifier, the implicit
2081 object parameter has reference type. */
2082 bool rv = FUNCTION_RVALUE_QUALIFIED (TREE_TYPE (fn));
2083 parmtype = cp_build_reference_type (parmtype, rv);
2084 /* The special handling of 'this' conversions in compare_ics
2085 does not apply if there is a ref-qualifier. */
2090 parmtype = build_pointer_type (parmtype);
2091 arg = build_this (arg);
2092 argtype = lvalue_type (arg);
2096 /* Core issue 899: When [copy-]initializing a temporary to be bound
2097 to the first parameter of a copy constructor (12.8) called with
2098 a single argument in the context of direct-initialization,
2099 explicit conversion functions are also considered.
2101 So set LOOKUP_COPY_PARM to let reference_binding know that
2102 it's being called in that context. We generalize the above
2103 to handle move constructors and template constructors as well;
2104 the standardese should soon be updated similarly. */
2105 if (ctype && i == 0 && (len-skip == 1)
2106 && DECL_CONSTRUCTOR_P (fn)
2107 && parmtype != error_mark_node
2108 && (same_type_ignoring_top_level_qualifiers_p
2109 (non_reference (parmtype), ctype)))
2111 if (!(flags & LOOKUP_ONLYCONVERTING))
2112 lflags |= LOOKUP_COPY_PARM;
2113 /* We allow user-defined conversions within init-lists, but
2114 don't list-initialize the copy parm, as that would mean
2115 using two levels of braces for the same type. */
2116 if ((flags & LOOKUP_LIST_INIT_CTOR)
2117 && BRACE_ENCLOSED_INITIALIZER_P (arg))
2118 lflags |= LOOKUP_NO_CONVERSION;
2121 lflags |= LOOKUP_ONLYCONVERTING;
2123 t = implicit_conversion (parmtype, argtype, arg,
2124 /*c_cast_p=*/false, lflags, complain);
2129 t = build_identity_conv (argtype, arg);
2130 t->ellipsis_p = true;
2141 reason = arg_conversion_rejection (first_arg, i, argtype, to_type);
2148 reason = bad_arg_conversion_rejection (first_arg, i, arg, to_type);
2153 return add_candidate (candidates, fn, orig_first_arg, args, len, convs,
2154 access_path, conversion_path, viable, reason, flags);
2157 /* Create an overload candidate for the conversion function FN which will
2158 be invoked for expression OBJ, producing a pointer-to-function which
2159 will in turn be called with the argument list FIRST_ARG/ARGLIST,
2160 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
2161 passed on to implicit_conversion.
2163 Actually, we don't really care about FN; we care about the type it
2164 converts to. There may be multiple conversion functions that will
2165 convert to that type, and we rely on build_user_type_conversion_1 to
2166 choose the best one; so when we create our candidate, we record the type
2167 instead of the function. */
2169 static struct z_candidate *
2170 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
2171 tree first_arg, const vec<tree, va_gc> *arglist,
2172 tree access_path, tree conversion_path,
2173 tsubst_flags_t complain)
2175 tree totype = TREE_TYPE (TREE_TYPE (fn));
2176 int i, len, viable, flags;
2177 tree parmlist, parmnode;
2179 struct rejection_reason *reason;
2181 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
2182 parmlist = TREE_TYPE (parmlist);
2183 parmlist = TYPE_ARG_TYPES (parmlist);
2185 len = vec_safe_length (arglist) + (first_arg != NULL_TREE ? 1 : 0) + 1;
2186 convs = alloc_conversions (len);
2187 parmnode = parmlist;
2189 flags = LOOKUP_IMPLICIT;
2192 /* Don't bother looking up the same type twice. */
2193 if (*candidates && (*candidates)->fn == totype)
2196 for (i = 0; i < len; ++i)
2198 tree arg, argtype, convert_type = NULL_TREE;
2203 else if (i == 1 && first_arg != NULL_TREE)
2206 arg = (*arglist)[i - (first_arg != NULL_TREE ? 1 : 0) - 1];
2207 argtype = lvalue_type (arg);
2211 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
2213 convert_type = totype;
2215 else if (parmnode == void_list_node)
2219 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
2220 /*c_cast_p=*/false, flags, complain);
2221 convert_type = TREE_VALUE (parmnode);
2225 t = build_identity_conv (argtype, arg);
2226 t->ellipsis_p = true;
2227 convert_type = argtype;
2237 reason = bad_arg_conversion_rejection (NULL_TREE, i, arg, convert_type);
2244 parmnode = TREE_CHAIN (parmnode);
2248 || ! sufficient_parms_p (parmnode))
2250 int remaining = remaining_arguments (parmnode);
2252 reason = arity_rejection (NULL_TREE, i + remaining, len);
2255 return add_candidate (candidates, totype, first_arg, arglist, len, convs,
2256 access_path, conversion_path, viable, reason, flags);
2260 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
2261 tree type1, tree type2, tree *args, tree *argtypes,
2262 int flags, tsubst_flags_t complain)
2269 struct rejection_reason *reason = NULL;
2274 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
2275 convs = alloc_conversions (num_convs);
2277 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
2278 conversion ops are allowed. We handle that here by just checking for
2279 boolean_type_node because other operators don't ask for it. COND_EXPR
2280 also does contextual conversion to bool for the first operand, but we
2281 handle that in build_conditional_expr, and type1 here is operand 2. */
2282 if (type1 != boolean_type_node)
2283 flags |= LOOKUP_ONLYCONVERTING;
2285 for (i = 0; i < 2; ++i)
2290 t = implicit_conversion (types[i], argtypes[i], args[i],
2291 /*c_cast_p=*/false, flags, complain);
2295 /* We need something for printing the candidate. */
2296 t = build_identity_conv (types[i], NULL_TREE);
2297 reason = arg_conversion_rejection (NULL_TREE, i, argtypes[i],
2303 reason = bad_arg_conversion_rejection (NULL_TREE, i, args[i],
2309 /* For COND_EXPR we rearranged the arguments; undo that now. */
2312 convs[2] = convs[1];
2313 convs[1] = convs[0];
2314 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
2315 /*c_cast_p=*/false, flags,
2322 reason = arg_conversion_rejection (NULL_TREE, 0, argtypes[2],
2327 add_candidate (candidates, fnname, /*first_arg=*/NULL_TREE, /*args=*/NULL,
2329 /*access_path=*/NULL_TREE,
2330 /*conversion_path=*/NULL_TREE,
2331 viable, reason, flags);
2335 is_complete (tree t)
2337 return COMPLETE_TYPE_P (complete_type (t));
2340 /* Returns nonzero if TYPE is a promoted arithmetic type. */
2343 promoted_arithmetic_type_p (tree type)
2347 In this section, the term promoted integral type is used to refer
2348 to those integral types which are preserved by integral promotion
2349 (including e.g. int and long but excluding e.g. char).
2350 Similarly, the term promoted arithmetic type refers to promoted
2351 integral types plus floating types. */
2352 return ((CP_INTEGRAL_TYPE_P (type)
2353 && same_type_p (type_promotes_to (type), type))
2354 || TREE_CODE (type) == REAL_TYPE);
2357 /* Create any builtin operator overload candidates for the operator in
2358 question given the converted operand types TYPE1 and TYPE2. The other
2359 args are passed through from add_builtin_candidates to
2360 build_builtin_candidate.
2362 TYPE1 and TYPE2 may not be permissible, and we must filter them.
2363 If CODE is requires candidates operands of the same type of the kind
2364 of which TYPE1 and TYPE2 are, we add both candidates
2365 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
2368 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
2369 enum tree_code code2, tree fnname, tree type1,
2370 tree type2, tree *args, tree *argtypes, int flags,
2371 tsubst_flags_t complain)
2375 case POSTINCREMENT_EXPR:
2376 case POSTDECREMENT_EXPR:
2377 args[1] = integer_zero_node;
2378 type2 = integer_type_node;
2387 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2388 and VQ is either volatile or empty, there exist candidate operator
2389 functions of the form
2390 VQ T& operator++(VQ T&);
2391 T operator++(VQ T&, int);
2392 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
2393 type other than bool, and VQ is either volatile or empty, there exist
2394 candidate operator functions of the form
2395 VQ T& operator--(VQ T&);
2396 T operator--(VQ T&, int);
2397 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
2398 complete object type, and VQ is either volatile or empty, there exist
2399 candidate operator functions of the form
2400 T*VQ& operator++(T*VQ&);
2401 T*VQ& operator--(T*VQ&);
2402 T* operator++(T*VQ&, int);
2403 T* operator--(T*VQ&, int); */
2405 case POSTDECREMENT_EXPR:
2406 case PREDECREMENT_EXPR:
2407 if (TREE_CODE (type1) == BOOLEAN_TYPE)
2409 case POSTINCREMENT_EXPR:
2410 case PREINCREMENT_EXPR:
2411 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
2413 type1 = build_reference_type (type1);
2418 /* 7 For every cv-qualified or cv-unqualified object type T, there
2419 exist candidate operator functions of the form
2423 8 For every function type T, there exist candidate operator functions of
2425 T& operator*(T*); */
2428 if (TYPE_PTR_P (type1)
2429 && (TYPE_PTROB_P (type1)
2430 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
2434 /* 9 For every type T, there exist candidate operator functions of the form
2437 10For every promoted arithmetic type T, there exist candidate operator
2438 functions of the form
2442 case UNARY_PLUS_EXPR: /* unary + */
2443 if (TYPE_PTR_P (type1))
2446 if (ARITHMETIC_TYPE_P (type1))
2450 /* 11For every promoted integral type T, there exist candidate operator
2451 functions of the form
2455 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1))
2459 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
2460 is the same type as C2 or is a derived class of C2, T is a complete
2461 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
2462 there exist candidate operator functions of the form
2463 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
2464 where CV12 is the union of CV1 and CV2. */
2467 if (TYPE_PTR_P (type1) && TYPE_PTRMEM_P (type2))
2469 tree c1 = TREE_TYPE (type1);
2470 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
2472 if (MAYBE_CLASS_TYPE_P (c1) && DERIVED_FROM_P (c2, c1)
2473 && (TYPE_PTRMEMFUNC_P (type2)
2474 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
2479 /* 13For every pair of promoted arithmetic types L and R, there exist can-
2480 didate operator functions of the form
2485 bool operator<(L, R);
2486 bool operator>(L, R);
2487 bool operator<=(L, R);
2488 bool operator>=(L, R);
2489 bool operator==(L, R);
2490 bool operator!=(L, R);
2491 where LR is the result of the usual arithmetic conversions between
2494 14For every pair of types T and I, where T is a cv-qualified or cv-
2495 unqualified complete object type and I is a promoted integral type,
2496 there exist candidate operator functions of the form
2497 T* operator+(T*, I);
2498 T& operator[](T*, I);
2499 T* operator-(T*, I);
2500 T* operator+(I, T*);
2501 T& operator[](I, T*);
2503 15For every T, where T is a pointer to complete object type, there exist
2504 candidate operator functions of the form112)
2505 ptrdiff_t operator-(T, T);
2507 16For every pointer or enumeration type T, there exist candidate operator
2508 functions of the form
2509 bool operator<(T, T);
2510 bool operator>(T, T);
2511 bool operator<=(T, T);
2512 bool operator>=(T, T);
2513 bool operator==(T, T);
2514 bool operator!=(T, T);
2516 17For every pointer to member type T, there exist candidate operator
2517 functions of the form
2518 bool operator==(T, T);
2519 bool operator!=(T, T); */
2522 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
2524 if (TYPE_PTROB_P (type1)
2525 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2527 type2 = ptrdiff_type_node;
2531 case TRUNC_DIV_EXPR:
2532 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2538 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2539 || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2)))
2541 if (TYPE_PTRMEM_P (type1) && null_ptr_cst_p (args[1]))
2546 if (TYPE_PTRMEM_P (type2) && null_ptr_cst_p (args[0]))
2558 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2560 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2562 if (TREE_CODE (type1) == ENUMERAL_TYPE
2563 && TREE_CODE (type2) == ENUMERAL_TYPE)
2565 if (TYPE_PTR_P (type1)
2566 && null_ptr_cst_p (args[1]))
2571 if (null_ptr_cst_p (args[0])
2572 && TYPE_PTR_P (type2))
2580 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2583 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && TYPE_PTROB_P (type2))
2585 type1 = ptrdiff_type_node;
2588 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2590 type2 = ptrdiff_type_node;
2595 /* 18For every pair of promoted integral types L and R, there exist candi-
2596 date operator functions of the form
2603 where LR is the result of the usual arithmetic conversions between
2606 case TRUNC_MOD_EXPR:
2612 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2616 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2617 type, VQ is either volatile or empty, and R is a promoted arithmetic
2618 type, there exist candidate operator functions of the form
2619 VQ L& operator=(VQ L&, R);
2620 VQ L& operator*=(VQ L&, R);
2621 VQ L& operator/=(VQ L&, R);
2622 VQ L& operator+=(VQ L&, R);
2623 VQ L& operator-=(VQ L&, R);
2625 20For every pair T, VQ), where T is any type and VQ is either volatile
2626 or empty, there exist candidate operator functions of the form
2627 T*VQ& operator=(T*VQ&, T*);
2629 21For every pair T, VQ), where T is a pointer to member type and VQ is
2630 either volatile or empty, there exist candidate operator functions of
2632 VQ T& operator=(VQ T&, T);
2634 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2635 unqualified complete object type, VQ is either volatile or empty, and
2636 I is a promoted integral type, there exist candidate operator func-
2638 T*VQ& operator+=(T*VQ&, I);
2639 T*VQ& operator-=(T*VQ&, I);
2641 23For every triple L, VQ, R), where L is an integral or enumeration
2642 type, VQ is either volatile or empty, and R is a promoted integral
2643 type, there exist candidate operator functions of the form
2645 VQ L& operator%=(VQ L&, R);
2646 VQ L& operator<<=(VQ L&, R);
2647 VQ L& operator>>=(VQ L&, R);
2648 VQ L& operator&=(VQ L&, R);
2649 VQ L& operator^=(VQ L&, R);
2650 VQ L& operator|=(VQ L&, R); */
2657 if (TYPE_PTROB_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2659 type2 = ptrdiff_type_node;
2663 case TRUNC_DIV_EXPR:
2664 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2668 case TRUNC_MOD_EXPR:
2674 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2679 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
2681 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
2682 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2683 || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2))
2684 || ((TYPE_PTRMEMFUNC_P (type1)
2685 || TYPE_PTR_P (type1))
2686 && null_ptr_cst_p (args[1])))
2696 type1 = build_reference_type (type1);
2702 For every pair of promoted arithmetic types L and R, there
2703 exist candidate operator functions of the form
2705 LR operator?(bool, L, R);
2707 where LR is the result of the usual arithmetic conversions
2708 between types L and R.
2710 For every type T, where T is a pointer or pointer-to-member
2711 type, there exist candidate operator functions of the form T
2712 operator?(bool, T, T); */
2714 if (promoted_arithmetic_type_p (type1)
2715 && promoted_arithmetic_type_p (type2))
2719 /* Otherwise, the types should be pointers. */
2720 if (!TYPE_PTR_OR_PTRMEM_P (type1) || !TYPE_PTR_OR_PTRMEM_P (type2))
2723 /* We don't check that the two types are the same; the logic
2724 below will actually create two candidates; one in which both
2725 parameter types are TYPE1, and one in which both parameter
2731 if (ARITHMETIC_TYPE_P (type1))
2739 /* Make sure we don't create builtin candidates with dependent types. */
2740 bool u1 = uses_template_parms (type1);
2741 bool u2 = type2 ? uses_template_parms (type2) : false;
2744 /* Try to recover if one of the types is non-dependent. But if
2745 there's only one type, there's nothing we can do. */
2748 /* And we lose if both are dependent. */
2751 /* Or if they have different forms. */
2752 if (TREE_CODE (type1) != TREE_CODE (type2))
2761 /* If we're dealing with two pointer types or two enumeral types,
2762 we need candidates for both of them. */
2763 if (type2 && !same_type_p (type1, type2)
2764 && TREE_CODE (type1) == TREE_CODE (type2)
2765 && (TREE_CODE (type1) == REFERENCE_TYPE
2766 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2767 || (TYPE_PTRDATAMEM_P (type1) && TYPE_PTRDATAMEM_P (type2))
2768 || TYPE_PTRMEMFUNC_P (type1)
2769 || MAYBE_CLASS_TYPE_P (type1)
2770 || TREE_CODE (type1) == ENUMERAL_TYPE))
2772 if (TYPE_PTR_OR_PTRMEM_P (type1))
2774 tree cptype = composite_pointer_type (type1, type2,
2779 if (cptype != error_mark_node)
2781 build_builtin_candidate
2782 (candidates, fnname, cptype, cptype, args, argtypes,
2788 build_builtin_candidate
2789 (candidates, fnname, type1, type1, args, argtypes, flags, complain);
2790 build_builtin_candidate
2791 (candidates, fnname, type2, type2, args, argtypes, flags, complain);
2795 build_builtin_candidate
2796 (candidates, fnname, type1, type2, args, argtypes, flags, complain);
2800 type_decays_to (tree type)
2802 if (TREE_CODE (type) == ARRAY_TYPE)
2803 return build_pointer_type (TREE_TYPE (type));
2804 if (TREE_CODE (type) == FUNCTION_TYPE)
2805 return build_pointer_type (type);
2809 /* There are three conditions of builtin candidates:
2811 1) bool-taking candidates. These are the same regardless of the input.
2812 2) pointer-pair taking candidates. These are generated for each type
2813 one of the input types converts to.
2814 3) arithmetic candidates. According to the standard, we should generate
2815 all of these, but I'm trying not to...
2817 Here we generate a superset of the possible candidates for this particular
2818 case. That is a subset of the full set the standard defines, plus some
2819 other cases which the standard disallows. add_builtin_candidate will
2820 filter out the invalid set. */
2823 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2824 enum tree_code code2, tree fnname, tree *args,
2825 int flags, tsubst_flags_t complain)
2829 tree type, argtypes[3], t;
2830 /* TYPES[i] is the set of possible builtin-operator parameter types
2831 we will consider for the Ith argument. */
2832 vec<tree, va_gc> *types[2];
2835 for (i = 0; i < 3; ++i)
2838 argtypes[i] = unlowered_expr_type (args[i]);
2840 argtypes[i] = NULL_TREE;
2845 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2846 and VQ is either volatile or empty, there exist candidate operator
2847 functions of the form
2848 VQ T& operator++(VQ T&); */
2850 case POSTINCREMENT_EXPR:
2851 case PREINCREMENT_EXPR:
2852 case POSTDECREMENT_EXPR:
2853 case PREDECREMENT_EXPR:
2858 /* 24There also exist candidate operator functions of the form
2859 bool operator!(bool);
2860 bool operator&&(bool, bool);
2861 bool operator||(bool, bool); */
2863 case TRUTH_NOT_EXPR:
2864 build_builtin_candidate
2865 (candidates, fnname, boolean_type_node,
2866 NULL_TREE, args, argtypes, flags, complain);
2869 case TRUTH_ORIF_EXPR:
2870 case TRUTH_ANDIF_EXPR:
2871 build_builtin_candidate
2872 (candidates, fnname, boolean_type_node,
2873 boolean_type_node, args, argtypes, flags, complain);
2895 types[0] = make_tree_vector ();
2896 types[1] = make_tree_vector ();
2898 for (i = 0; i < 2; ++i)
2902 else if (MAYBE_CLASS_TYPE_P (argtypes[i]))
2906 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2909 convs = lookup_conversions (argtypes[i]);
2911 if (code == COND_EXPR)
2913 if (real_lvalue_p (args[i]))
2914 vec_safe_push (types[i], build_reference_type (argtypes[i]));
2916 vec_safe_push (types[i], TYPE_MAIN_VARIANT (argtypes[i]));
2922 for (; convs; convs = TREE_CHAIN (convs))
2924 type = TREE_TYPE (convs);
2927 && (TREE_CODE (type) != REFERENCE_TYPE
2928 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2931 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2932 vec_safe_push (types[i], type);
2934 type = non_reference (type);
2935 if (i != 0 || ! ref1)
2937 type = cv_unqualified (type_decays_to (type));
2938 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2939 vec_safe_push (types[i], type);
2940 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2941 type = type_promotes_to (type);
2944 if (! vec_member (type, types[i]))
2945 vec_safe_push (types[i], type);
2950 if (code == COND_EXPR && real_lvalue_p (args[i]))
2951 vec_safe_push (types[i], build_reference_type (argtypes[i]));
2952 type = non_reference (argtypes[i]);
2953 if (i != 0 || ! ref1)
2955 type = cv_unqualified (type_decays_to (type));
2956 if (enum_p && UNSCOPED_ENUM_P (type))
2957 vec_safe_push (types[i], type);
2958 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
2959 type = type_promotes_to (type);
2961 vec_safe_push (types[i], type);
2965 /* Run through the possible parameter types of both arguments,
2966 creating candidates with those parameter types. */
2967 FOR_EACH_VEC_ELT_REVERSE (*(types[0]), ix, t)
2972 if (!types[1]->is_empty ())
2973 FOR_EACH_VEC_ELT_REVERSE (*(types[1]), jx, u)
2974 add_builtin_candidate
2975 (candidates, code, code2, fnname, t,
2976 u, args, argtypes, flags, complain);
2978 add_builtin_candidate
2979 (candidates, code, code2, fnname, t,
2980 NULL_TREE, args, argtypes, flags, complain);
2983 release_tree_vector (types[0]);
2984 release_tree_vector (types[1]);
2988 /* If TMPL can be successfully instantiated as indicated by
2989 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2991 TMPL is the template. EXPLICIT_TARGS are any explicit template
2992 arguments. ARGLIST is the arguments provided at the call-site.
2993 This does not change ARGLIST. The RETURN_TYPE is the desired type
2994 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2995 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2996 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2998 static struct z_candidate*
2999 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
3000 tree ctype, tree explicit_targs, tree first_arg,
3001 const vec<tree, va_gc> *arglist, tree return_type,
3002 tree access_path, tree conversion_path,
3003 int flags, tree obj, unification_kind_t strict,
3004 tsubst_flags_t complain)
3006 int ntparms = DECL_NTPARMS (tmpl);
3007 tree targs = make_tree_vec (ntparms);
3008 unsigned int len = vec_safe_length (arglist);
3009 unsigned int nargs = (first_arg == NULL_TREE ? 0 : 1) + len;
3010 unsigned int skip_without_in_chrg = 0;
3011 tree first_arg_without_in_chrg = first_arg;
3012 tree *args_without_in_chrg;
3013 unsigned int nargs_without_in_chrg;
3014 unsigned int ia, ix;
3016 struct z_candidate *cand;
3018 struct rejection_reason *reason = NULL;
3021 /* We don't do deduction on the in-charge parameter, the VTT
3022 parameter or 'this'. */
3023 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
3025 if (first_arg_without_in_chrg != NULL_TREE)
3026 first_arg_without_in_chrg = NULL_TREE;
3028 ++skip_without_in_chrg;
3031 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
3032 || DECL_BASE_CONSTRUCTOR_P (tmpl))
3033 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
3035 if (first_arg_without_in_chrg != NULL_TREE)
3036 first_arg_without_in_chrg = NULL_TREE;
3038 ++skip_without_in_chrg;
3041 if (len < skip_without_in_chrg)
3044 nargs_without_in_chrg = ((first_arg_without_in_chrg != NULL_TREE ? 1 : 0)
3045 + (len - skip_without_in_chrg));
3046 args_without_in_chrg = XALLOCAVEC (tree, nargs_without_in_chrg);
3048 if (first_arg_without_in_chrg != NULL_TREE)
3050 args_without_in_chrg[ia] = first_arg_without_in_chrg;
3053 for (ix = skip_without_in_chrg;
3054 vec_safe_iterate (arglist, ix, &arg);
3057 args_without_in_chrg[ia] = arg;
3060 gcc_assert (ia == nargs_without_in_chrg);
3062 errs = errorcount+sorrycount;
3063 fn = fn_type_unification (tmpl, explicit_targs, targs,
3064 args_without_in_chrg,
3065 nargs_without_in_chrg,
3066 return_type, strict, flags, false,
3067 complain & tf_decltype);
3069 if (fn == error_mark_node)
3071 /* Don't repeat unification later if it already resulted in errors. */
3072 if (errorcount+sorrycount == errs)
3073 reason = template_unification_rejection (tmpl, explicit_targs,
3074 targs, args_without_in_chrg,
3075 nargs_without_in_chrg,
3076 return_type, strict, flags);
3078 reason = template_unification_error_rejection ();
3084 A member function template is never instantiated to perform the
3085 copy of a class object to an object of its class type.
3087 It's a little unclear what this means; the standard explicitly
3088 does allow a template to be used to copy a class. For example,
3093 template <class T> A(const T&);
3096 void g () { A a (f ()); }
3098 the member template will be used to make the copy. The section
3099 quoted above appears in the paragraph that forbids constructors
3100 whose only parameter is (a possibly cv-qualified variant of) the
3101 class type, and a logical interpretation is that the intent was
3102 to forbid the instantiation of member templates which would then
3104 if (DECL_CONSTRUCTOR_P (fn) && nargs == 2)
3106 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
3107 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
3110 reason = invalid_copy_with_fn_template_rejection ();
3115 if (obj != NULL_TREE)
3116 /* Aha, this is a conversion function. */
3117 cand = add_conv_candidate (candidates, fn, obj, first_arg, arglist,
3118 access_path, conversion_path, complain);
3120 cand = add_function_candidate (candidates, fn, ctype,
3121 first_arg, arglist, access_path,
3122 conversion_path, flags, complain);
3123 if (DECL_TI_TEMPLATE (fn) != tmpl)
3124 /* This situation can occur if a member template of a template
3125 class is specialized. Then, instantiate_template might return
3126 an instantiation of the specialization, in which case the
3127 DECL_TI_TEMPLATE field will point at the original
3128 specialization. For example:
3130 template <class T> struct S { template <class U> void f(U);
3131 template <> void f(int) {}; };
3135 Here, TMPL will be template <class U> S<double>::f(U).
3136 And, instantiate template will give us the specialization
3137 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
3138 for this will point at template <class T> template <> S<T>::f(int),
3139 so that we can find the definition. For the purposes of
3140 overload resolution, however, we want the original TMPL. */
3141 cand->template_decl = build_template_info (tmpl, targs);
3143 cand->template_decl = DECL_TEMPLATE_INFO (fn);
3144 cand->explicit_targs = explicit_targs;
3148 return add_candidate (candidates, tmpl, first_arg, arglist, nargs, NULL,
3149 access_path, conversion_path, 0, reason, flags);
3153 static struct z_candidate *
3154 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
3155 tree explicit_targs, tree first_arg,
3156 const vec<tree, va_gc> *arglist, tree return_type,
3157 tree access_path, tree conversion_path, int flags,
3158 unification_kind_t strict, tsubst_flags_t complain)
3161 add_template_candidate_real (candidates, tmpl, ctype,
3162 explicit_targs, first_arg, arglist,
3163 return_type, access_path, conversion_path,
3164 flags, NULL_TREE, strict, complain);
3168 static struct z_candidate *
3169 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
3170 tree obj, tree first_arg,
3171 const vec<tree, va_gc> *arglist,
3172 tree return_type, tree access_path,
3173 tree conversion_path, tsubst_flags_t complain)
3176 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
3177 first_arg, arglist, return_type, access_path,
3178 conversion_path, 0, obj, DEDUCE_CONV,
3182 /* The CANDS are the set of candidates that were considered for
3183 overload resolution. Return the set of viable candidates, or CANDS
3184 if none are viable. If any of the candidates were viable, set
3185 *ANY_VIABLE_P to true. STRICT_P is true if a candidate should be
3186 considered viable only if it is strictly viable. */
3188 static struct z_candidate*
3189 splice_viable (struct z_candidate *cands,
3193 struct z_candidate *viable;
3194 struct z_candidate **last_viable;
3195 struct z_candidate **cand;
3196 bool found_strictly_viable = false;
3198 /* Be strict inside templates, since build_over_call won't actually
3199 do the conversions to get pedwarns. */
3200 if (processing_template_decl)
3204 last_viable = &viable;
3205 *any_viable_p = false;
3210 struct z_candidate *c = *cand;
3212 && (c->viable == 1 || TREE_CODE (c->fn) == TEMPLATE_DECL))
3214 /* Be strict in the presence of a viable candidate. Also if
3215 there are template candidates, so that we get deduction errors
3216 for them instead of silently preferring a bad conversion. */
3218 if (viable && !found_strictly_viable)
3220 /* Put any spliced near matches back onto the main list so
3221 that we see them if there is no strict match. */
3222 *any_viable_p = false;
3223 *last_viable = cands;
3226 last_viable = &viable;
3230 if (strict_p ? c->viable == 1 : c->viable)
3235 last_viable = &c->next;
3236 *any_viable_p = true;
3238 found_strictly_viable = true;
3244 return viable ? viable : cands;
3248 any_strictly_viable (struct z_candidate *cands)
3250 for (; cands; cands = cands->next)
3251 if (cands->viable == 1)
3256 /* OBJ is being used in an expression like "OBJ.f (...)". In other
3257 words, it is about to become the "this" pointer for a member
3258 function call. Take the address of the object. */
3261 build_this (tree obj)
3263 /* In a template, we are only concerned about the type of the
3264 expression, so we can take a shortcut. */
3265 if (processing_template_decl)
3266 return build_address (obj);
3268 return cp_build_addr_expr (obj, tf_warning_or_error);
3271 /* Returns true iff functions are equivalent. Equivalent functions are
3272 not '==' only if one is a function-local extern function or if
3273 both are extern "C". */
3276 equal_functions (tree fn1, tree fn2)
3278 if (TREE_CODE (fn1) != TREE_CODE (fn2))
3280 if (TREE_CODE (fn1) == TEMPLATE_DECL)
3282 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
3283 || DECL_EXTERN_C_FUNCTION_P (fn1))
3284 return decls_match (fn1, fn2);
3288 /* Print information about a candidate being rejected due to INFO. */
3291 print_conversion_rejection (location_t loc, struct conversion_info *info)
3293 tree from = info->from;
3295 from = lvalue_type (from);
3296 if (info->n_arg == -1)
3298 /* Conversion of implicit `this' argument failed. */
3299 if (!TYPE_P (info->from))
3300 /* A bad conversion for 'this' must be discarding cv-quals. */
3301 inform (loc, " passing %qT as %<this%> "
3302 "argument discards qualifiers",
3305 inform (loc, " no known conversion for implicit "
3306 "%<this%> parameter from %qT to %qT",
3307 from, info->to_type);
3309 else if (!TYPE_P (info->from))
3311 if (info->n_arg >= 0)
3312 inform (loc, " conversion of argument %d would be ill-formed:",
3314 perform_implicit_conversion (info->to_type, info->from,
3315 tf_warning_or_error);
3317 else if (info->n_arg == -2)
3318 /* Conversion of conversion function return value failed. */
3319 inform (loc, " no known conversion from %qT to %qT",
3320 from, info->to_type);
3322 inform (loc, " no known conversion for argument %d from %qT to %qT",
3323 info->n_arg + 1, from, info->to_type);
3326 /* Print information about a candidate with WANT parameters and we found
3330 print_arity_information (location_t loc, unsigned int have, unsigned int want)
3332 inform_n (loc, want,
3333 " candidate expects %d argument, %d provided",
3334 " candidate expects %d arguments, %d provided",
3338 /* Print information about one overload candidate CANDIDATE. MSGSTR
3339 is the text to print before the candidate itself.
3341 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
3342 to have been run through gettext by the caller. This wart makes
3343 life simpler in print_z_candidates and for the translators. */
3346 print_z_candidate (location_t loc, const char *msgstr,
3347 struct z_candidate *candidate)
3349 const char *msg = (msgstr == NULL
3351 : ACONCAT ((msgstr, " ", NULL)));
3352 location_t cloc = location_of (candidate->fn);
3354 if (identifier_p (candidate->fn))
3357 if (candidate->num_convs == 3)
3358 inform (cloc, "%s%D(%T, %T, %T) <built-in>", msg, candidate->fn,
3359 candidate->convs[0]->type,
3360 candidate->convs[1]->type,
3361 candidate->convs[2]->type);
3362 else if (candidate->num_convs == 2)
3363 inform (cloc, "%s%D(%T, %T) <built-in>", msg, candidate->fn,
3364 candidate->convs[0]->type,
3365 candidate->convs[1]->type);
3367 inform (cloc, "%s%D(%T) <built-in>", msg, candidate->fn,
3368 candidate->convs[0]->type);
3370 else if (TYPE_P (candidate->fn))
3371 inform (cloc, "%s%T <conversion>", msg, candidate->fn);
3372 else if (candidate->viable == -1)
3373 inform (cloc, "%s%#D <near match>", msg, candidate->fn);
3374 else if (DECL_DELETED_FN (candidate->fn))
3375 inform (cloc, "%s%#D <deleted>", msg, candidate->fn);
3377 inform (cloc, "%s%#D", msg, candidate->fn);
3378 /* Give the user some information about why this candidate failed. */
3379 if (candidate->reason != NULL)
3381 struct rejection_reason *r = candidate->reason;
3386 print_arity_information (cloc, r->u.arity.actual,
3387 r->u.arity.expected);
3389 case rr_arg_conversion:
3390 print_conversion_rejection (cloc, &r->u.conversion);
3392 case rr_bad_arg_conversion:
3393 print_conversion_rejection (cloc, &r->u.bad_conversion);
3395 case rr_explicit_conversion:
3396 inform (cloc, " return type %qT of explicit conversion function "
3397 "cannot be converted to %qT with a qualification "
3398 "conversion", r->u.conversion.from,
3399 r->u.conversion.to_type);
3401 case rr_template_conversion:
3402 inform (cloc, " conversion from return type %qT of template "
3403 "conversion function specialization to %qT is not an "
3404 "exact match", r->u.conversion.from,
3405 r->u.conversion.to_type);
3407 case rr_template_unification:
3408 /* We use template_unification_error_rejection if unification caused
3409 actual non-SFINAE errors, in which case we don't need to repeat
3411 if (r->u.template_unification.tmpl == NULL_TREE)
3413 inform (cloc, " substitution of deduced template arguments "
3414 "resulted in errors seen above");
3417 /* Re-run template unification with diagnostics. */
3418 inform (cloc, " template argument deduction/substitution failed:");
3419 fn_type_unification (r->u.template_unification.tmpl,
3420 r->u.template_unification.explicit_targs,
3422 (r->u.template_unification.num_targs)),
3423 r->u.template_unification.args,
3424 r->u.template_unification.nargs,
3425 r->u.template_unification.return_type,
3426 r->u.template_unification.strict,
3427 r->u.template_unification.flags,
3430 case rr_invalid_copy:
3432 " a constructor taking a single argument of its own "
3433 "class type is invalid");
3437 /* This candidate didn't have any issues or we failed to
3438 handle a particular code. Either way... */
3445 print_z_candidates (location_t loc, struct z_candidate *candidates)
3447 struct z_candidate *cand1;
3448 struct z_candidate **cand2;
3454 /* Remove non-viable deleted candidates. */
3456 for (cand2 = &cand1; *cand2; )
3458 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
3459 && !(*cand2)->viable
3460 && DECL_DELETED_FN ((*cand2)->fn))
3461 *cand2 = (*cand2)->next;
3463 cand2 = &(*cand2)->next;
3465 /* ...if there are any non-deleted ones. */
3469 /* There may be duplicates in the set of candidates. We put off
3470 checking this condition as long as possible, since we have no way
3471 to eliminate duplicates from a set of functions in less than n^2
3472 time. Now we are about to emit an error message, so it is more
3473 permissible to go slowly. */
3474 for (cand1 = candidates; cand1; cand1 = cand1->next)
3476 tree fn = cand1->fn;
3477 /* Skip builtin candidates and conversion functions. */
3480 cand2 = &cand1->next;
3483 if (DECL_P ((*cand2)->fn)
3484 && equal_functions (fn, (*cand2)->fn))
3485 *cand2 = (*cand2)->next;
3487 cand2 = &(*cand2)->next;
3491 for (n_candidates = 0, cand1 = candidates; cand1; cand1 = cand1->next)
3494 for (; candidates; candidates = candidates->next)
3495 print_z_candidate (loc, "candidate:", candidates);
3498 /* USER_SEQ is a user-defined conversion sequence, beginning with a
3499 USER_CONV. STD_SEQ is the standard conversion sequence applied to
3500 the result of the conversion function to convert it to the final
3501 desired type. Merge the two sequences into a single sequence,
3502 and return the merged sequence. */
3505 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
3508 bool bad = user_seq->bad_p;
3510 gcc_assert (user_seq->kind == ck_user);
3512 /* Find the end of the second conversion sequence. */
3513 for (t = &std_seq; (*t)->kind != ck_identity; t = &((*t)->u.next))
3515 /* The entire sequence is a user-conversion sequence. */
3516 (*t)->user_conv_p = true;
3521 /* Replace the identity conversion with the user conversion
3528 /* Handle overload resolution for initializing an object of class type from
3529 an initializer list. First we look for a suitable constructor that
3530 takes a std::initializer_list; if we don't find one, we then look for a
3531 non-list constructor.
3533 Parameters are as for add_candidates, except that the arguments are in
3534 the form of a CONSTRUCTOR (the initializer list) rather than a vector, and
3535 the RETURN_TYPE parameter is replaced by TOTYPE, the desired type. */
3538 add_list_candidates (tree fns, tree first_arg,
3539 tree init_list, tree totype,
3540 tree explicit_targs, bool template_only,
3541 tree conversion_path, tree access_path,
3543 struct z_candidate **candidates,
3544 tsubst_flags_t complain)
3546 vec<tree, va_gc> *args;
3548 gcc_assert (*candidates == NULL);
3550 /* We're looking for a ctor for list-initialization. */
3551 flags |= LOOKUP_LIST_INIT_CTOR;
3552 /* And we don't allow narrowing conversions. We also use this flag to
3553 avoid the copy constructor call for copy-list-initialization. */
3554 flags |= LOOKUP_NO_NARROWING;
3556 /* Always use the default constructor if the list is empty (DR 990). */
3557 if (CONSTRUCTOR_NELTS (init_list) == 0
3558 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
3560 /* If the class has a list ctor, try passing the list as a single
3561 argument first, but only consider list ctors. */
3562 else if (TYPE_HAS_LIST_CTOR (totype))
3564 flags |= LOOKUP_LIST_ONLY;
3565 args = make_tree_vector_single (init_list);
3566 add_candidates (fns, first_arg, args, NULL_TREE,
3567 explicit_targs, template_only, conversion_path,
3568 access_path, flags, candidates, complain);
3569 if (any_strictly_viable (*candidates))
3573 args = ctor_to_vec (init_list);
3575 /* We aren't looking for list-ctors anymore. */
3576 flags &= ~LOOKUP_LIST_ONLY;
3577 /* We allow more user-defined conversions within an init-list. */
3578 flags &= ~LOOKUP_NO_CONVERSION;
3580 add_candidates (fns, first_arg, args, NULL_TREE,
3581 explicit_targs, template_only, conversion_path,
3582 access_path, flags, candidates, complain);
3585 /* Returns the best overload candidate to perform the requested
3586 conversion. This function is used for three the overloading situations
3587 described in [over.match.copy], [over.match.conv], and [over.match.ref].
3588 If TOTYPE is a REFERENCE_TYPE, we're trying to find a direct binding as
3589 per [dcl.init.ref], so we ignore temporary bindings. */
3591 static struct z_candidate *
3592 build_user_type_conversion_1 (tree totype, tree expr, int flags,
3593 tsubst_flags_t complain)
3595 struct z_candidate *candidates, *cand;
3597 tree ctors = NULL_TREE;
3598 tree conv_fns = NULL_TREE;
3599 conversion *conv = NULL;
3600 tree first_arg = NULL_TREE;
3601 vec<tree, va_gc> *args = NULL;
3608 fromtype = TREE_TYPE (expr);
3610 /* We represent conversion within a hierarchy using RVALUE_CONV and
3611 BASE_CONV, as specified by [over.best.ics]; these become plain
3612 constructor calls, as specified in [dcl.init]. */
3613 gcc_assert (!MAYBE_CLASS_TYPE_P (fromtype) || !MAYBE_CLASS_TYPE_P (totype)
3614 || !DERIVED_FROM_P (totype, fromtype));
3616 if (MAYBE_CLASS_TYPE_P (totype))
3617 /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
3618 creating a garbage BASELINK; constructors can't be inherited. */
3619 ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
3621 if (MAYBE_CLASS_TYPE_P (fromtype))
3623 tree to_nonref = non_reference (totype);
3624 if (same_type_ignoring_top_level_qualifiers_p (to_nonref, fromtype) ||
3625 (CLASS_TYPE_P (to_nonref) && CLASS_TYPE_P (fromtype)
3626 && DERIVED_FROM_P (to_nonref, fromtype)))
3628 /* [class.conv.fct] A conversion function is never used to
3629 convert a (possibly cv-qualified) object to the (possibly
3630 cv-qualified) same object type (or a reference to it), to a
3631 (possibly cv-qualified) base class of that type (or a
3632 reference to it)... */
3635 conv_fns = lookup_conversions (fromtype);
3639 flags |= LOOKUP_NO_CONVERSION;
3640 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3641 flags |= LOOKUP_NO_NARROWING;
3643 /* It's OK to bind a temporary for converting constructor arguments, but
3644 not in converting the return value of a conversion operator. */
3645 convflags = ((flags & LOOKUP_NO_TEMP_BIND) | LOOKUP_NO_CONVERSION
3646 | (flags & LOOKUP_NO_NARROWING));
3647 flags &= ~LOOKUP_NO_TEMP_BIND;
3651 int ctorflags = flags;
3653 first_arg = build_dummy_object (totype);
3655 /* We should never try to call the abstract or base constructor
3657 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
3658 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
3660 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
3662 /* List-initialization. */
3663 add_list_candidates (ctors, first_arg, expr, totype, NULL_TREE,
3664 false, TYPE_BINFO (totype), TYPE_BINFO (totype),
3665 ctorflags, &candidates, complain);
3669 args = make_tree_vector_single (expr);
3670 add_candidates (ctors, first_arg, args, NULL_TREE, NULL_TREE, false,
3671 TYPE_BINFO (totype), TYPE_BINFO (totype),
3672 ctorflags, &candidates, complain);
3675 for (cand = candidates; cand; cand = cand->next)
3677 cand->second_conv = build_identity_conv (totype, NULL_TREE);
3679 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
3680 set, then this is copy-initialization. In that case, "The
3681 result of the call is then used to direct-initialize the
3682 object that is the destination of the copy-initialization."
3685 We represent this in the conversion sequence with an
3686 rvalue conversion, which means a constructor call. */
3687 if (TREE_CODE (totype) != REFERENCE_TYPE
3688 && !(convflags & LOOKUP_NO_TEMP_BIND))
3690 = build_conv (ck_rvalue, totype, cand->second_conv);
3697 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
3699 tree conversion_path = TREE_PURPOSE (conv_fns);
3700 struct z_candidate *old_candidates;
3702 /* If we are called to convert to a reference type, we are trying to
3703 find a direct binding, so don't even consider temporaries. If
3704 we don't find a direct binding, the caller will try again to
3705 look for a temporary binding. */
3706 if (TREE_CODE (totype) == REFERENCE_TYPE)
3707 convflags |= LOOKUP_NO_TEMP_BIND;
3709 old_candidates = candidates;
3710 add_candidates (TREE_VALUE (conv_fns), first_arg, NULL, totype,
3712 conversion_path, TYPE_BINFO (fromtype),
3713 flags, &candidates, complain);
3715 for (cand = candidates; cand != old_candidates; cand = cand->next)
3717 tree rettype = TREE_TYPE (TREE_TYPE (cand->fn));
3719 = implicit_conversion (totype,
3722 /*c_cast_p=*/false, convflags,
3725 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
3726 copy-initialization. In that case, "The result of the
3727 call is then used to direct-initialize the object that is
3728 the destination of the copy-initialization." [dcl.init]
3730 We represent this in the conversion sequence with an
3731 rvalue conversion, which means a constructor call. But
3732 don't add a second rvalue conversion if there's already
3733 one there. Which there really shouldn't be, but it's
3734 harmless since we'd add it here anyway. */
3735 if (ics && MAYBE_CLASS_TYPE_P (totype) && ics->kind != ck_rvalue
3736 && !(convflags & LOOKUP_NO_TEMP_BIND))
3737 ics = build_conv (ck_rvalue, totype, ics);
3739 cand->second_conv = ics;
3744 cand->reason = arg_conversion_rejection (NULL_TREE, -2,
3747 else if (DECL_NONCONVERTING_P (cand->fn)
3748 && ics->rank > cr_exact)
3750 /* 13.3.1.5: For direct-initialization, those explicit
3751 conversion functions that are not hidden within S and
3752 yield type T or a type that can be converted to type T
3753 with a qualification conversion (4.4) are also candidate
3755 /* 13.3.1.6 doesn't have a parallel restriction, but it should;
3756 I've raised this issue with the committee. --jason 9/2011 */
3758 cand->reason = explicit_conversion_rejection (rettype, totype);
3760 else if (cand->viable == 1 && ics->bad_p)
3764 = bad_arg_conversion_rejection (NULL_TREE, -2,
3767 else if (primary_template_instantiation_p (cand->fn)
3768 && ics->rank > cr_exact)
3770 /* 13.3.3.1.2: If the user-defined conversion is specified by
3771 a specialization of a conversion function template, the
3772 second standard conversion sequence shall have exact match
3775 cand->reason = template_conversion_rejection (rettype, totype);
3780 candidates = splice_viable (candidates, false, &any_viable_p);
3784 release_tree_vector (args);
3788 cand = tourney (candidates, complain);
3791 if (complain & tf_error)
3793 error ("conversion from %qT to %qT is ambiguous",
3795 print_z_candidates (location_of (expr), candidates);
3798 cand = candidates; /* any one will do */
3799 cand->second_conv = build_ambiguous_conv (totype, expr);
3800 cand->second_conv->user_conv_p = true;
3801 if (!any_strictly_viable (candidates))
3802 cand->second_conv->bad_p = true;
3803 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3804 ambiguous conversion is no worse than another user-defined
3811 if (!DECL_CONSTRUCTOR_P (cand->fn))
3812 convtype = non_reference (TREE_TYPE (TREE_TYPE (cand->fn)));
3813 else if (cand->second_conv->kind == ck_rvalue)
3814 /* DR 5: [in the first step of copy-initialization]...if the function
3815 is a constructor, the call initializes a temporary of the
3816 cv-unqualified version of the destination type. */
3817 convtype = cv_unqualified (totype);
3820 /* Build the user conversion sequence. */
3824 build_identity_conv (TREE_TYPE (expr), expr));
3826 if (cand->viable == -1)
3829 /* Remember that this was a list-initialization. */
3830 if (flags & LOOKUP_NO_NARROWING)
3831 conv->check_narrowing = true;
3833 /* Combine it with the second conversion sequence. */
3834 cand->second_conv = merge_conversion_sequences (conv,
3840 /* Wrapper for above. */
3843 build_user_type_conversion (tree totype, tree expr, int flags,
3844 tsubst_flags_t complain)
3846 struct z_candidate *cand;
3849 bool subtime = timevar_cond_start (TV_OVERLOAD);
3850 cand = build_user_type_conversion_1 (totype, expr, flags, complain);
3854 if (cand->second_conv->kind == ck_ambig)
3855 ret = error_mark_node;
3858 expr = convert_like (cand->second_conv, expr, complain);
3859 ret = convert_from_reference (expr);
3865 timevar_cond_stop (TV_OVERLOAD, subtime);
3869 /* Subroutine of convert_nontype_argument.
3871 EXPR is an argument for a template non-type parameter of integral or
3872 enumeration type. Do any necessary conversions (that are permitted for
3873 non-type arguments) to convert it to the parameter type.
3875 If conversion is successful, returns the converted expression;
3876 otherwise, returns error_mark_node. */
3879 build_integral_nontype_arg_conv (tree type, tree expr, tsubst_flags_t complain)
3884 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
3886 if (error_operand_p (expr))
3887 return error_mark_node;
3889 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
3891 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3892 p = conversion_obstack_alloc (0);
3894 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
3896 LOOKUP_IMPLICIT, complain);
3898 /* for a non-type template-parameter of integral or
3899 enumeration type, integral promotions (4.5) and integral
3900 conversions (4.7) are applied. */
3901 /* It should be sufficient to check the outermost conversion step, since
3902 there are no qualification conversions to integer type. */
3906 /* A conversion function is OK. If it isn't constexpr, we'll
3907 complain later that the argument isn't constant. */
3909 /* The lvalue-to-rvalue conversion is OK. */
3915 t = next_conversion (conv)->type;
3916 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t))
3919 if (complain & tf_error)
3920 error_at (loc, "conversion from %qT to %qT not considered for "
3921 "non-type template argument", t, type);
3922 /* and fall through. */
3930 expr = convert_like (conv, expr, complain);
3932 expr = error_mark_node;
3934 /* Free all the conversions we allocated. */
3935 obstack_free (&conversion_obstack, p);
3940 /* Do any initial processing on the arguments to a function call. */
3942 static vec<tree, va_gc> *
3943 resolve_args (vec<tree, va_gc> *args, tsubst_flags_t complain)
3948 FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
3950 if (error_operand_p (arg))
3952 else if (VOID_TYPE_P (TREE_TYPE (arg)))
3954 if (complain & tf_error)
3955 error ("invalid use of void expression");
3958 else if (invalid_nonstatic_memfn_p (arg, complain))
3964 /* Perform overload resolution on FN, which is called with the ARGS.
3966 Return the candidate function selected by overload resolution, or
3967 NULL if the event that overload resolution failed. In the case
3968 that overload resolution fails, *CANDIDATES will be the set of
3969 candidates considered, and ANY_VIABLE_P will be set to true or
3970 false to indicate whether or not any of the candidates were
3973 The ARGS should already have gone through RESOLVE_ARGS before this
3974 function is called. */
3976 static struct z_candidate *
3977 perform_overload_resolution (tree fn,
3978 const vec<tree, va_gc> *args,
3979 struct z_candidate **candidates,
3980 bool *any_viable_p, tsubst_flags_t complain)
3982 struct z_candidate *cand;
3983 tree explicit_targs;
3986 bool subtime = timevar_cond_start (TV_OVERLOAD);
3988 explicit_targs = NULL_TREE;
3992 *any_viable_p = true;
3995 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
3996 || TREE_CODE (fn) == TEMPLATE_DECL
3997 || TREE_CODE (fn) == OVERLOAD
3998 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
4000 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
4002 explicit_targs = TREE_OPERAND (fn, 1);
4003 fn = TREE_OPERAND (fn, 0);
4007 /* Add the various candidate functions. */
4008 add_candidates (fn, NULL_TREE, args, NULL_TREE,
4009 explicit_targs, template_only,
4010 /*conversion_path=*/NULL_TREE,
4011 /*access_path=*/NULL_TREE,
4013 candidates, complain);
4015 *candidates = splice_viable (*candidates, false, any_viable_p);
4017 cand = tourney (*candidates, complain);
4021 timevar_cond_stop (TV_OVERLOAD, subtime);
4025 /* Print an error message about being unable to build a call to FN with
4026 ARGS. ANY_VIABLE_P indicates whether any candidate functions could
4027 be located; CANDIDATES is a possibly empty list of such
4031 print_error_for_call_failure (tree fn, vec<tree, va_gc> *args,
4032 struct z_candidate *candidates)
4034 tree name = DECL_NAME (OVL_CURRENT (fn));
4035 location_t loc = location_of (name);
4037 if (!any_strictly_viable (candidates))
4038 error_at (loc, "no matching function for call to %<%D(%A)%>",
4039 name, build_tree_list_vec (args));
4041 error_at (loc, "call of overloaded %<%D(%A)%> is ambiguous",
4042 name, build_tree_list_vec (args));
4044 print_z_candidates (loc, candidates);
4047 /* Return an expression for a call to FN (a namespace-scope function,
4048 or a static member function) with the ARGS. This may change
4052 build_new_function_call (tree fn, vec<tree, va_gc> **args, bool koenig_p,
4053 tsubst_flags_t complain)
4055 struct z_candidate *candidates, *cand;
4060 if (args != NULL && *args != NULL)
4062 *args = resolve_args (*args, complain);
4064 return error_mark_node;
4068 tm_malloc_replacement (fn);
4070 /* If this function was found without using argument dependent
4071 lookup, then we want to ignore any undeclared friend
4077 fn = remove_hidden_names (fn);
4080 if (complain & tf_error)
4081 print_error_for_call_failure (orig_fn, *args, NULL);
4082 return error_mark_node;
4086 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4087 p = conversion_obstack_alloc (0);
4089 cand = perform_overload_resolution (fn, *args, &candidates, &any_viable_p,
4094 if (complain & tf_error)
4096 if (!any_viable_p && candidates && ! candidates->next
4097 && (TREE_CODE (candidates->fn) == FUNCTION_DECL))
4098 return cp_build_function_call_vec (candidates->fn, args, complain);
4099 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
4100 fn = TREE_OPERAND (fn, 0);
4101 print_error_for_call_failure (fn, *args, candidates);
4103 result = error_mark_node;
4107 int flags = LOOKUP_NORMAL;
4108 /* If fn is template_id_expr, the call has explicit template arguments
4109 (e.g. func<int>(5)), communicate this info to build_over_call
4110 through flags so that later we can use it to decide whether to warn
4111 about peculiar null pointer conversion. */
4112 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
4113 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
4114 result = build_over_call (cand, flags, complain);
4117 /* Free all the conversions we allocated. */
4118 obstack_free (&conversion_obstack, p);
4123 /* Build a call to a global operator new. FNNAME is the name of the
4124 operator (either "operator new" or "operator new[]") and ARGS are
4125 the arguments provided. This may change ARGS. *SIZE points to the
4126 total number of bytes required by the allocation, and is updated if
4127 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
4128 be used. If this function determines that no cookie should be
4129 used, after all, *COOKIE_SIZE is set to NULL_TREE. If SIZE_CHECK
4130 is not NULL_TREE, it is evaluated before calculating the final
4131 array size, and if it fails, the array size is replaced with
4132 (size_t)-1 (usually triggering a std::bad_alloc exception). If FN
4133 is non-NULL, it will be set, upon return, to the allocation
4137 build_operator_new_call (tree fnname, vec<tree, va_gc> **args,
4138 tree *size, tree *cookie_size, tree size_check,
4139 tree *fn, tsubst_flags_t complain)
4141 tree original_size = *size;
4143 struct z_candidate *candidates;
4144 struct z_candidate *cand;
4149 /* Set to (size_t)-1 if the size check fails. */
4150 if (size_check != NULL_TREE)
4152 tree errval = TYPE_MAX_VALUE (sizetype);
4153 if (cxx_dialect >= cxx11 && flag_exceptions)
4154 errval = throw_bad_array_new_length ();
4155 *size = fold_build3 (COND_EXPR, sizetype, size_check,
4156 original_size, errval);
4158 vec_safe_insert (*args, 0, *size);
4159 *args = resolve_args (*args, complain);
4161 return error_mark_node;
4167 If this lookup fails to find the name, or if the allocated type
4168 is not a class type, the allocation function's name is looked
4169 up in the global scope.
4171 we disregard block-scope declarations of "operator new". */
4172 fns = lookup_function_nonclass (fnname, *args, /*block_p=*/false);
4174 /* Figure out what function is being called. */
4175 cand = perform_overload_resolution (fns, *args, &candidates, &any_viable_p,
4178 /* If no suitable function could be found, issue an error message
4182 if (complain & tf_error)
4183 print_error_for_call_failure (fns, *args, candidates);
4184 return error_mark_node;
4187 /* If a cookie is required, add some extra space. Whether
4188 or not a cookie is required cannot be determined until
4189 after we know which function was called. */
4192 bool use_cookie = true;
4195 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
4196 /* Skip the size_t parameter. */
4197 arg_types = TREE_CHAIN (arg_types);
4198 /* Check the remaining parameters (if any). */
4200 && TREE_CHAIN (arg_types) == void_list_node
4201 && same_type_p (TREE_VALUE (arg_types),
4204 /* If we need a cookie, adjust the number of bytes allocated. */
4207 /* Update the total size. */
4208 *size = size_binop (PLUS_EXPR, original_size, *cookie_size);
4209 /* Set to (size_t)-1 if the size check fails. */
4210 gcc_assert (size_check != NULL_TREE);
4211 *size = fold_build3 (COND_EXPR, sizetype, size_check,
4212 *size, TYPE_MAX_VALUE (sizetype));
4213 /* Update the argument list to reflect the adjusted size. */
4214 (**args)[0] = *size;
4217 *cookie_size = NULL_TREE;
4220 /* Tell our caller which function we decided to call. */
4224 /* Build the CALL_EXPR. */
4225 return build_over_call (cand, LOOKUP_NORMAL, complain);
4228 /* Build a new call to operator(). This may change ARGS. */
4231 build_op_call_1 (tree obj, vec<tree, va_gc> **args, tsubst_flags_t complain)
4233 struct z_candidate *candidates = 0, *cand;
4234 tree fns, convs, first_mem_arg = NULL_TREE;
4235 tree type = TREE_TYPE (obj);
4237 tree result = NULL_TREE;
4240 if (error_operand_p (obj))
4241 return error_mark_node;
4243 obj = prep_operand (obj);
4245 if (TYPE_PTRMEMFUNC_P (type))
4247 if (complain & tf_error)
4248 /* It's no good looking for an overloaded operator() on a
4249 pointer-to-member-function. */
4250 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
4251 return error_mark_node;
4254 if (TYPE_BINFO (type))
4256 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
4257 if (fns == error_mark_node)
4258 return error_mark_node;
4263 if (args != NULL && *args != NULL)
4265 *args = resolve_args (*args, complain);
4267 return error_mark_node;
4270 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4271 p = conversion_obstack_alloc (0);
4275 first_mem_arg = obj;
4277 add_candidates (BASELINK_FUNCTIONS (fns),
4278 first_mem_arg, *args, NULL_TREE,
4280 BASELINK_BINFO (fns), BASELINK_ACCESS_BINFO (fns),
4281 LOOKUP_NORMAL, &candidates, complain);
4284 convs = lookup_conversions (type);
4286 for (; convs; convs = TREE_CHAIN (convs))
4288 tree fns = TREE_VALUE (convs);
4289 tree totype = TREE_TYPE (convs);
4291 if (TYPE_PTRFN_P (totype)
4292 || TYPE_REFFN_P (totype)
4293 || (TREE_CODE (totype) == REFERENCE_TYPE
4294 && TYPE_PTRFN_P (TREE_TYPE (totype))))
4295 for (; fns; fns = OVL_NEXT (fns))
4297 tree fn = OVL_CURRENT (fns);
4299 if (DECL_NONCONVERTING_P (fn))
4302 if (TREE_CODE (fn) == TEMPLATE_DECL)
4303 add_template_conv_candidate
4304 (&candidates, fn, obj, NULL_TREE, *args, totype,
4305 /*access_path=*/NULL_TREE,
4306 /*conversion_path=*/NULL_TREE, complain);
4308 add_conv_candidate (&candidates, fn, obj, NULL_TREE,
4309 *args, /*conversion_path=*/NULL_TREE,
4310 /*access_path=*/NULL_TREE, complain);
4314 /* Be strict here because if we choose a bad conversion candidate, the
4315 errors we get won't mention the call context. */
4316 candidates = splice_viable (candidates, true, &any_viable_p);
4319 if (complain & tf_error)
4321 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj),
4322 build_tree_list_vec (*args));
4323 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4325 result = error_mark_node;
4329 cand = tourney (candidates, complain);
4332 if (complain & tf_error)
4334 error ("call of %<(%T) (%A)%> is ambiguous",
4335 TREE_TYPE (obj), build_tree_list_vec (*args));
4336 print_z_candidates (location_of (TREE_TYPE (obj)), candidates);
4338 result = error_mark_node;
4340 /* Since cand->fn will be a type, not a function, for a conversion
4341 function, we must be careful not to unconditionally look at
4343 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
4344 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
4345 result = build_over_call (cand, LOOKUP_NORMAL, complain);
4348 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1,
4350 obj = convert_from_reference (obj);
4351 result = cp_build_function_call_vec (obj, args, complain);
4355 /* Free all the conversions we allocated. */
4356 obstack_free (&conversion_obstack, p);
4361 /* Wrapper for above. */
4364 build_op_call (tree obj, vec<tree, va_gc> **args, tsubst_flags_t complain)
4367 bool subtime = timevar_cond_start (TV_OVERLOAD);
4368 ret = build_op_call_1 (obj, args, complain);
4369 timevar_cond_stop (TV_OVERLOAD, subtime);
4373 /* Called by op_error to prepare format strings suitable for the error
4374 function. It concatenates a prefix (controlled by MATCH), ERRMSG,
4375 and a suffix (controlled by NTYPES). */
4378 op_error_string (const char *errmsg, int ntypes, bool match)
4382 const char *msgp = concat (match ? G_("ambiguous overload for ")
4383 : G_("no match for "), errmsg, NULL);
4386 msg = concat (msgp, G_(" (operand types are %qT, %qT, and %qT)"), NULL);
4387 else if (ntypes == 2)
4388 msg = concat (msgp, G_(" (operand types are %qT and %qT)"), NULL);
4390 msg = concat (msgp, G_(" (operand type is %qT)"), NULL);
4396 op_error (location_t loc, enum tree_code code, enum tree_code code2,
4397 tree arg1, tree arg2, tree arg3, bool match)
4401 if (code == MODIFY_EXPR)
4402 opname = assignment_operator_name_info[code2].name;
4404 opname = operator_name_info[code].name;
4409 if (flag_diagnostics_show_caret)
4410 error_at (loc, op_error_string (G_("ternary %<operator?:%>"),
4412 TREE_TYPE (arg1), TREE_TYPE (arg2), TREE_TYPE (arg3));
4414 error_at (loc, op_error_string (G_("ternary %<operator?:%> "
4415 "in %<%E ? %E : %E%>"), 3, match),
4417 TREE_TYPE (arg1), TREE_TYPE (arg2), TREE_TYPE (arg3));
4420 case POSTINCREMENT_EXPR:
4421 case POSTDECREMENT_EXPR:
4422 if (flag_diagnostics_show_caret)
4423 error_at (loc, op_error_string (G_("%<operator%s%>"), 1, match),
4424 opname, TREE_TYPE (arg1));
4426 error_at (loc, op_error_string (G_("%<operator%s%> in %<%E%s%>"),
4428 opname, arg1, opname, TREE_TYPE (arg1));
4432 if (flag_diagnostics_show_caret)
4433 error_at (loc, op_error_string (G_("%<operator[]%>"), 2, match),
4434 TREE_TYPE (arg1), TREE_TYPE (arg2));
4436 error_at (loc, op_error_string (G_("%<operator[]%> in %<%E[%E]%>"),
4438 arg1, arg2, TREE_TYPE (arg1), TREE_TYPE (arg2));
4443 if (flag_diagnostics_show_caret)
4444 error_at (loc, op_error_string (G_("%qs"), 1, match),
4445 opname, TREE_TYPE (arg1));
4447 error_at (loc, op_error_string (G_("%qs in %<%s %E%>"), 1, match),
4448 opname, opname, arg1, TREE_TYPE (arg1));
4453 if (flag_diagnostics_show_caret)
4454 error_at (loc, op_error_string (G_("%<operator%s%>"), 2, match),
4455 opname, TREE_TYPE (arg1), TREE_TYPE (arg2));
4457 error_at (loc, op_error_string (G_("%<operator%s%> in %<%E %s %E%>"),
4459 opname, arg1, opname, arg2,
4460 TREE_TYPE (arg1), TREE_TYPE (arg2));
4462 if (flag_diagnostics_show_caret)
4463 error_at (loc, op_error_string (G_("%<operator%s%>"), 1, match),
4464 opname, TREE_TYPE (arg1));
4466 error_at (loc, op_error_string (G_("%<operator%s%> in %<%s%E%>"),
4468 opname, opname, arg1, TREE_TYPE (arg1));
4473 /* Return the implicit conversion sequence that could be used to
4474 convert E1 to E2 in [expr.cond]. */
4477 conditional_conversion (tree e1, tree e2, tsubst_flags_t complain)
4479 tree t1 = non_reference (TREE_TYPE (e1));
4480 tree t2 = non_reference (TREE_TYPE (e2));
4486 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4487 implicitly converted (clause _conv_) to the type "lvalue reference to
4488 T2", subject to the constraint that in the conversion the
4489 reference must bind directly (_dcl.init.ref_) to an lvalue.
4491 If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4492 implicitly converted to the type "rvalue reference to T2", subject to
4493 the constraint that the reference must bind directly. */
4494 if (lvalue_or_rvalue_with_address_p (e2))
4496 tree rtype = cp_build_reference_type (t2, !real_lvalue_p (e2));
4497 conv = implicit_conversion (rtype,
4501 LOOKUP_NO_TEMP_BIND|LOOKUP_NO_RVAL_BIND
4502 |LOOKUP_ONLYCONVERTING,
4504 if (conv && !conv->bad_p)
4508 /* If E2 is a prvalue or if neither of the conversions above can be done
4509 and at least one of the operands has (possibly cv-qualified) class
4511 if (!CLASS_TYPE_P (t1) && !CLASS_TYPE_P (t2))
4516 If E1 and E2 have class type, and the underlying class types are
4517 the same or one is a base class of the other: E1 can be converted
4518 to match E2 if the class of T2 is the same type as, or a base
4519 class of, the class of T1, and the cv-qualification of T2 is the
4520 same cv-qualification as, or a greater cv-qualification than, the
4521 cv-qualification of T1. If the conversion is applied, E1 is
4522 changed to an rvalue of type T2 that still refers to the original
4523 source class object (or the appropriate subobject thereof). */
4524 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
4525 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
4527 if (good_base && at_least_as_qualified_p (t2, t1))
4529 conv = build_identity_conv (t1, e1);
4530 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
4531 TYPE_MAIN_VARIANT (t2)))
4532 conv = build_conv (ck_base, t2, conv);
4534 conv = build_conv (ck_rvalue, t2, conv);
4543 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
4544 converted to the type that expression E2 would have if E2 were
4545 converted to an rvalue (or the type it has, if E2 is an rvalue). */
4546 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
4547 LOOKUP_IMPLICIT, complain);
4550 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
4551 arguments to the conditional expression. */
4554 build_conditional_expr_1 (location_t loc, tree arg1, tree arg2, tree arg3,
4555 tsubst_flags_t complain)
4559 tree result = NULL_TREE;
4560 tree result_type = NULL_TREE;
4561 bool lvalue_p = true;
4562 struct z_candidate *candidates = 0;
4563 struct z_candidate *cand;
4565 tree orig_arg2, orig_arg3;
4567 /* As a G++ extension, the second argument to the conditional can be
4568 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
4569 c'.) If the second operand is omitted, make sure it is
4570 calculated only once. */
4573 if (complain & tf_error)
4574 pedwarn (loc, OPT_Wpedantic,
4575 "ISO C++ forbids omitting the middle term of a ?: expression");
4577 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
4578 if (real_lvalue_p (arg1))
4579 arg2 = arg1 = stabilize_reference (arg1);
4581 arg2 = arg1 = save_expr (arg1);
4584 /* If something has already gone wrong, just pass that fact up the
4586 if (error_operand_p (arg1)
4587 || error_operand_p (arg2)
4588 || error_operand_p (arg3))
4589 return error_mark_node;
4594 if (VECTOR_INTEGER_TYPE_P (TREE_TYPE (arg1)))
4596 arg1 = force_rvalue (arg1, complain);
4597 arg2 = force_rvalue (arg2, complain);
4598 arg3 = force_rvalue (arg3, complain);
4600 /* force_rvalue can return error_mark on valid arguments. */
4601 if (error_operand_p (arg1)
4602 || error_operand_p (arg2)
4603 || error_operand_p (arg3))
4604 return error_mark_node;
4606 tree arg1_type = TREE_TYPE (arg1);
4607 arg2_type = TREE_TYPE (arg2);
4608 arg3_type = TREE_TYPE (arg3);
4610 if (TREE_CODE (arg2_type) != VECTOR_TYPE
4611 && TREE_CODE (arg3_type) != VECTOR_TYPE)
4613 /* Rely on the error messages of the scalar version. */
4614 tree scal = build_conditional_expr_1 (loc, integer_one_node,
4615 orig_arg2, orig_arg3, complain);
4616 if (scal == error_mark_node)
4617 return error_mark_node;
4618 tree stype = TREE_TYPE (scal);
4619 tree ctype = TREE_TYPE (arg1_type);
4620 if (TYPE_SIZE (stype) != TYPE_SIZE (ctype)
4621 || (!INTEGRAL_TYPE_P (stype) && !SCALAR_FLOAT_TYPE_P (stype)))
4623 if (complain & tf_error)
4624 error_at (loc, "inferred scalar type %qT is not an integer or "
4625 "floating point type of the same size as %qT", stype,
4626 COMPARISON_CLASS_P (arg1)
4627 ? TREE_TYPE (TREE_TYPE (TREE_OPERAND (arg1, 0)))
4629 return error_mark_node;
4632 tree vtype = build_opaque_vector_type (stype,
4633 TYPE_VECTOR_SUBPARTS (arg1_type));
4634 /* We could pass complain & tf_warning to unsafe_conversion_p,
4635 but the warnings (like Wsign-conversion) have already been
4636 given by the scalar build_conditional_expr_1. We still check
4637 unsafe_conversion_p to forbid truncating long long -> float. */
4638 if (unsafe_conversion_p (loc, stype, arg2, false))
4640 if (complain & tf_error)
4641 error_at (loc, "conversion of scalar %qT to vector %qT "
4642 "involves truncation", arg2_type, vtype);
4643 return error_mark_node;
4645 if (unsafe_conversion_p (loc, stype, arg3, false))
4647 if (complain & tf_error)
4648 error_at (loc, "conversion of scalar %qT to vector %qT "
4649 "involves truncation", arg3_type, vtype);
4650 return error_mark_node;
4653 arg2 = cp_convert (stype, arg2, complain);
4654 arg2 = save_expr (arg2);
4655 arg2 = build_vector_from_val (vtype, arg2);
4657 arg3 = cp_convert (stype, arg3, complain);
4658 arg3 = save_expr (arg3);
4659 arg3 = build_vector_from_val (vtype, arg3);
4663 if ((TREE_CODE (arg2_type) == VECTOR_TYPE)
4664 != (TREE_CODE (arg3_type) == VECTOR_TYPE))
4666 enum stv_conv convert_flag =
4667 scalar_to_vector (loc, VEC_COND_EXPR, arg2, arg3,
4668 complain & tf_error);
4670 switch (convert_flag)
4673 return error_mark_node;
4676 arg2 = save_expr (arg2);
4677 arg2 = convert (TREE_TYPE (arg3_type), arg2);
4678 arg2 = build_vector_from_val (arg3_type, arg2);
4679 arg2_type = TREE_TYPE (arg2);
4684 arg3 = save_expr (arg3);
4685 arg3 = convert (TREE_TYPE (arg2_type), arg3);
4686 arg3 = build_vector_from_val (arg2_type, arg3);
4687 arg3_type = TREE_TYPE (arg3);
4695 if (!same_type_p (arg2_type, arg3_type)
4696 || TYPE_VECTOR_SUBPARTS (arg1_type)
4697 != TYPE_VECTOR_SUBPARTS (arg2_type)
4698 || TYPE_SIZE (arg1_type) != TYPE_SIZE (arg2_type))
4700 if (complain & tf_error)
4702 "incompatible vector types in conditional expression: "
4703 "%qT, %qT and %qT", TREE_TYPE (arg1),
4704 TREE_TYPE (orig_arg2), TREE_TYPE (orig_arg3));
4705 return error_mark_node;
4708 if (!COMPARISON_CLASS_P (arg1))
4709 arg1 = cp_build_binary_op (loc, NE_EXPR, arg1,
4710 build_zero_cst (arg1_type), complain);
4711 return fold_build3 (VEC_COND_EXPR, arg2_type, arg1, arg2, arg3);
4716 The first expression is implicitly converted to bool (clause
4718 arg1 = perform_implicit_conversion_flags (boolean_type_node, arg1, complain,
4720 if (error_operand_p (arg1))
4721 return error_mark_node;
4725 If either the second or the third operand has type (possibly
4726 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
4727 array-to-pointer (_conv.array_), and function-to-pointer
4728 (_conv.func_) standard conversions are performed on the second
4729 and third operands. */
4730 arg2_type = unlowered_expr_type (arg2);
4731 arg3_type = unlowered_expr_type (arg3);
4732 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
4734 /* Do the conversions. We don't these for `void' type arguments
4735 since it can't have any effect and since decay_conversion
4736 does not handle that case gracefully. */
4737 if (!VOID_TYPE_P (arg2_type))
4738 arg2 = decay_conversion (arg2, complain);
4739 if (!VOID_TYPE_P (arg3_type))
4740 arg3 = decay_conversion (arg3, complain);
4741 arg2_type = TREE_TYPE (arg2);
4742 arg3_type = TREE_TYPE (arg3);
4746 One of the following shall hold:
4748 --The second or the third operand (but not both) is a
4749 throw-expression (_except.throw_); the result is of the
4750 type of the other and is an rvalue.
4752 --Both the second and the third operands have type void; the
4753 result is of type void and is an rvalue.
4755 We must avoid calling force_rvalue for expressions of type
4756 "void" because it will complain that their value is being
4758 if (TREE_CODE (arg2) == THROW_EXPR
4759 && TREE_CODE (arg3) != THROW_EXPR)
4761 if (!VOID_TYPE_P (arg3_type))
4763 arg3 = force_rvalue (arg3, complain);
4764 if (arg3 == error_mark_node)
4765 return error_mark_node;
4767 arg3_type = TREE_TYPE (arg3);
4768 result_type = arg3_type;
4770 else if (TREE_CODE (arg2) != THROW_EXPR
4771 && TREE_CODE (arg3) == THROW_EXPR)
4773 if (!VOID_TYPE_P (arg2_type))
4775 arg2 = force_rvalue (arg2, complain);
4776 if (arg2 == error_mark_node)
4777 return error_mark_node;
4779 arg2_type = TREE_TYPE (arg2);
4780 result_type = arg2_type;
4782 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
4783 result_type = void_type_node;
4786 if (complain & tf_error)
4788 if (VOID_TYPE_P (arg2_type))
4789 error_at (EXPR_LOC_OR_LOC (arg3, loc),
4790 "second operand to the conditional operator "
4791 "is of type %<void%>, but the third operand is "
4792 "neither a throw-expression nor of type %<void%>");
4794 error_at (EXPR_LOC_OR_LOC (arg2, loc),
4795 "third operand to the conditional operator "
4796 "is of type %<void%>, but the second operand is "
4797 "neither a throw-expression nor of type %<void%>");
4799 return error_mark_node;
4803 goto valid_operands;
4807 Otherwise, if the second and third operand have different types,
4808 and either has (possibly cv-qualified) class type, or if both are
4809 glvalues of the same value category and the same type except for
4810 cv-qualification, an attempt is made to convert each of those operands
4811 to the type of the other. */
4812 else if (!same_type_p (arg2_type, arg3_type)
4813 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)
4814 || (same_type_ignoring_top_level_qualifiers_p (arg2_type,
4816 && lvalue_or_rvalue_with_address_p (arg2)
4817 && lvalue_or_rvalue_with_address_p (arg3)
4818 && real_lvalue_p (arg2) == real_lvalue_p (arg3))))
4822 bool converted = false;
4824 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4825 p = conversion_obstack_alloc (0);
4827 conv2 = conditional_conversion (arg2, arg3, complain);
4828 conv3 = conditional_conversion (arg3, arg2, complain);
4832 If both can be converted, or one can be converted but the
4833 conversion is ambiguous, the program is ill-formed. If
4834 neither can be converted, the operands are left unchanged and
4835 further checking is performed as described below. If exactly
4836 one conversion is possible, that conversion is applied to the
4837 chosen operand and the converted operand is used in place of
4838 the original operand for the remainder of this section. */
4839 if ((conv2 && !conv2->bad_p
4840 && conv3 && !conv3->bad_p)
4841 || (conv2 && conv2->kind == ck_ambig)
4842 || (conv3 && conv3->kind == ck_ambig))
4844 if (complain & tf_error)
4846 error_at (loc, "operands to ?: have different types %qT and %qT",
4847 arg2_type, arg3_type);
4848 if (conv2 && !conv2->bad_p && conv3 && !conv3->bad_p)
4849 inform (loc, " and each type can be converted to the other");
4850 else if (conv2 && conv2->kind == ck_ambig)
4851 convert_like (conv2, arg2, complain);
4853 convert_like (conv3, arg3, complain);
4855 result = error_mark_node;
4857 else if (conv2 && !conv2->bad_p)
4859 arg2 = convert_like (conv2, arg2, complain);
4860 arg2 = convert_from_reference (arg2);
4861 arg2_type = TREE_TYPE (arg2);
4862 /* Even if CONV2 is a valid conversion, the result of the
4863 conversion may be invalid. For example, if ARG3 has type
4864 "volatile X", and X does not have a copy constructor
4865 accepting a "volatile X&", then even if ARG2 can be
4866 converted to X, the conversion will fail. */
4867 if (error_operand_p (arg2))
4868 result = error_mark_node;
4871 else if (conv3 && !conv3->bad_p)
4873 arg3 = convert_like (conv3, arg3, complain);
4874 arg3 = convert_from_reference (arg3);
4875 arg3_type = TREE_TYPE (arg3);
4876 if (error_operand_p (arg3))
4877 result = error_mark_node;
4881 /* Free all the conversions we allocated. */
4882 obstack_free (&conversion_obstack, p);
4887 /* If, after the conversion, both operands have class type,
4888 treat the cv-qualification of both operands as if it were the
4889 union of the cv-qualification of the operands.
4891 The standard is not clear about what to do in this
4892 circumstance. For example, if the first operand has type
4893 "const X" and the second operand has a user-defined
4894 conversion to "volatile X", what is the type of the second
4895 operand after this step? Making it be "const X" (matching
4896 the first operand) seems wrong, as that discards the
4897 qualification without actually performing a copy. Leaving it
4898 as "volatile X" seems wrong as that will result in the
4899 conditional expression failing altogether, even though,
4900 according to this step, the one operand could be converted to
4901 the type of the other. */
4903 && CLASS_TYPE_P (arg2_type)
4904 && cp_type_quals (arg2_type) != cp_type_quals (arg3_type))
4905 arg2_type = arg3_type =
4906 cp_build_qualified_type (arg2_type,
4907 cp_type_quals (arg2_type)
4908 | cp_type_quals (arg3_type));
4913 If the second and third operands are glvalues of the same value
4914 category and have the same type, the result is of that type and
4916 if (((real_lvalue_p (arg2) && real_lvalue_p (arg3))
4917 || (xvalue_p (arg2) && xvalue_p (arg3)))
4918 && same_type_p (arg2_type, arg3_type))
4920 result_type = arg2_type;
4921 arg2 = mark_lvalue_use (arg2);
4922 arg3 = mark_lvalue_use (arg3);
4923 goto valid_operands;
4928 Otherwise, the result is an rvalue. If the second and third
4929 operand do not have the same type, and either has (possibly
4930 cv-qualified) class type, overload resolution is used to
4931 determine the conversions (if any) to be applied to the operands
4932 (_over.match.oper_, _over.built_). */
4934 if (!same_type_p (arg2_type, arg3_type)
4935 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
4941 /* Rearrange the arguments so that add_builtin_candidate only has
4942 to know about two args. In build_builtin_candidate, the
4943 arguments are unscrambled. */
4947 add_builtin_candidates (&candidates,
4950 ansi_opname (COND_EXPR),
4952 LOOKUP_NORMAL, complain);
4956 If the overload resolution fails, the program is
4958 candidates = splice_viable (candidates, false, &any_viable_p);
4961 if (complain & tf_error)
4962 error_at (loc, "operands to ?: have different types %qT and %qT",
4963 arg2_type, arg3_type);
4964 return error_mark_node;
4966 cand = tourney (candidates, complain);
4969 if (complain & tf_error)
4971 op_error (loc, COND_EXPR, NOP_EXPR, arg1, arg2, arg3, FALSE);
4972 print_z_candidates (loc, candidates);
4974 return error_mark_node;
4979 Otherwise, the conversions thus determined are applied, and
4980 the converted operands are used in place of the original
4981 operands for the remainder of this section. */
4982 conv = cand->convs[0];
4983 arg1 = convert_like (conv, arg1, complain);
4984 conv = cand->convs[1];
4985 arg2 = convert_like (conv, arg2, complain);
4986 arg2_type = TREE_TYPE (arg2);
4987 conv = cand->convs[2];
4988 arg3 = convert_like (conv, arg3, complain);
4989 arg3_type = TREE_TYPE (arg3);
4994 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
4995 and function-to-pointer (_conv.func_) standard conversions are
4996 performed on the second and third operands.
4998 We need to force the lvalue-to-rvalue conversion here for class types,
4999 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
5000 that isn't wrapped with a TARGET_EXPR plays havoc with exception
5003 arg2 = force_rvalue (arg2, complain);
5004 if (!CLASS_TYPE_P (arg2_type))
5005 arg2_type = TREE_TYPE (arg2);
5007 arg3 = force_rvalue (arg3, complain);
5008 if (!CLASS_TYPE_P (arg3_type))
5009 arg3_type = TREE_TYPE (arg3);
5011 if (arg2 == error_mark_node || arg3 == error_mark_node)
5012 return error_mark_node;
5016 After those conversions, one of the following shall hold:
5018 --The second and third operands have the same type; the result is of
5020 if (same_type_p (arg2_type, arg3_type))
5021 result_type = arg2_type;
5024 --The second and third operands have arithmetic or enumeration
5025 type; the usual arithmetic conversions are performed to bring
5026 them to a common type, and the result is of that type. */
5027 else if ((ARITHMETIC_TYPE_P (arg2_type)
5028 || UNSCOPED_ENUM_P (arg2_type))
5029 && (ARITHMETIC_TYPE_P (arg3_type)
5030 || UNSCOPED_ENUM_P (arg3_type)))
5032 /* In this case, there is always a common type. */
5033 result_type = type_after_usual_arithmetic_conversions (arg2_type,
5035 if (complain & tf_warning)
5036 do_warn_double_promotion (result_type, arg2_type, arg3_type,
5037 "implicit conversion from %qT to %qT to "
5038 "match other result of conditional",
5041 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
5042 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
5044 if (TREE_CODE (orig_arg2) == CONST_DECL
5045 && TREE_CODE (orig_arg3) == CONST_DECL
5046 && DECL_CONTEXT (orig_arg2) == DECL_CONTEXT (orig_arg3))
5047 /* Two enumerators from the same enumeration can have different
5048 types when the enumeration is still being defined. */;
5049 else if (complain & tf_warning)
5050 warning_at (loc, OPT_Wenum_compare, "enumeral mismatch in "
5051 "conditional expression: %qT vs %qT",
5052 arg2_type, arg3_type);
5054 else if (extra_warnings
5055 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
5056 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
5057 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
5058 && !same_type_p (arg2_type,
5059 type_promotes_to (arg3_type)))))
5061 if (complain & tf_warning)
5062 warning_at (loc, OPT_Wextra, "enumeral and non-enumeral type in "
5063 "conditional expression");
5066 arg2 = perform_implicit_conversion (result_type, arg2, complain);
5067 arg3 = perform_implicit_conversion (result_type, arg3, complain);
5071 --The second and third operands have pointer type, or one has
5072 pointer type and the other is a null pointer constant; pointer
5073 conversions (_conv.ptr_) and qualification conversions
5074 (_conv.qual_) are performed to bring them to their composite
5075 pointer type (_expr.rel_). The result is of the composite
5078 --The second and third operands have pointer to member type, or
5079 one has pointer to member type and the other is a null pointer
5080 constant; pointer to member conversions (_conv.mem_) and
5081 qualification conversions (_conv.qual_) are performed to bring
5082 them to a common type, whose cv-qualification shall match the
5083 cv-qualification of either the second or the third operand.
5084 The result is of the common type. */
5085 else if ((null_ptr_cst_p (arg2)
5086 && TYPE_PTR_OR_PTRMEM_P (arg3_type))
5087 || (null_ptr_cst_p (arg3)
5088 && TYPE_PTR_OR_PTRMEM_P (arg2_type))
5089 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
5090 || (TYPE_PTRDATAMEM_P (arg2_type) && TYPE_PTRDATAMEM_P (arg3_type))
5091 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
5093 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
5094 arg3, CPO_CONDITIONAL_EXPR,
5096 if (result_type == error_mark_node)
5097 return error_mark_node;
5098 arg2 = perform_implicit_conversion (result_type, arg2, complain);
5099 arg3 = perform_implicit_conversion (result_type, arg3, complain);
5104 if (complain & tf_error)
5105 error_at (loc, "operands to ?: have different types %qT and %qT",
5106 arg2_type, arg3_type);
5107 return error_mark_node;
5110 if (arg2 == error_mark_node || arg3 == error_mark_node)
5111 return error_mark_node;
5114 result = build3 (COND_EXPR, result_type, arg1, arg2, arg3);
5115 if (!cp_unevaluated_operand)
5116 /* Avoid folding within decltype (c++/42013) and noexcept. */
5117 result = fold_if_not_in_template (result);
5119 /* We can't use result_type below, as fold might have returned a
5124 /* Expand both sides into the same slot, hopefully the target of
5125 the ?: expression. We used to check for TARGET_EXPRs here,
5126 but now we sometimes wrap them in NOP_EXPRs so the test would
5128 if (CLASS_TYPE_P (TREE_TYPE (result)))
5129 result = get_target_expr_sfinae (result, complain);
5130 /* If this expression is an rvalue, but might be mistaken for an
5131 lvalue, we must add a NON_LVALUE_EXPR. */
5132 result = rvalue (result);
5135 result = force_paren_expr (result);
5140 /* Wrapper for above. */
5143 build_conditional_expr (location_t loc, tree arg1, tree arg2, tree arg3,
5144 tsubst_flags_t complain)
5147 bool subtime = timevar_cond_start (TV_OVERLOAD);
5148 ret = build_conditional_expr_1 (loc, arg1, arg2, arg3, complain);
5149 timevar_cond_stop (TV_OVERLOAD, subtime);
5153 /* OPERAND is an operand to an expression. Perform necessary steps
5154 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
5158 prep_operand (tree operand)
5162 if (CLASS_TYPE_P (TREE_TYPE (operand))
5163 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
5164 /* Make sure the template type is instantiated now. */
5165 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
5171 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
5172 OVERLOAD) to the CANDIDATES, returning an updated list of
5173 CANDIDATES. The ARGS are the arguments provided to the call;
5174 if FIRST_ARG is non-null it is the implicit object argument,
5175 otherwise the first element of ARGS is used if needed. The
5176 EXPLICIT_TARGS are explicit template arguments provided.
5177 TEMPLATE_ONLY is true if only template functions should be
5178 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
5179 add_function_candidate. */
5182 add_candidates (tree fns, tree first_arg, const vec<tree, va_gc> *args,
5184 tree explicit_targs, bool template_only,
5185 tree conversion_path, tree access_path,
5187 struct z_candidate **candidates,
5188 tsubst_flags_t complain)
5191 const vec<tree, va_gc> *non_static_args;
5192 bool check_list_ctor;
5193 bool check_converting;
5194 unification_kind_t strict;
5200 /* Precalculate special handling of constructors and conversion ops. */
5201 fn = OVL_CURRENT (fns);
5202 if (DECL_CONV_FN_P (fn))
5204 check_list_ctor = false;
5205 check_converting = !!(flags & LOOKUP_ONLYCONVERTING);
5206 if (flags & LOOKUP_NO_CONVERSION)
5207 /* We're doing return_type(x). */
5208 strict = DEDUCE_CONV;
5210 /* We're doing x.operator return_type(). */
5211 strict = DEDUCE_EXACT;
5212 /* [over.match.funcs] For conversion functions, the function
5213 is considered to be a member of the class of the implicit
5214 object argument for the purpose of defining the type of
5215 the implicit object parameter. */
5216 ctype = TYPE_MAIN_VARIANT (TREE_TYPE (first_arg));
5220 if (DECL_CONSTRUCTOR_P (fn))
5222 check_list_ctor = !!(flags & LOOKUP_LIST_ONLY);
5223 /* For list-initialization we consider explicit constructors
5224 and complain if one is chosen. */
5226 = ((flags & (LOOKUP_ONLYCONVERTING|LOOKUP_LIST_INIT_CTOR))
5227 == LOOKUP_ONLYCONVERTING);
5231 check_list_ctor = false;
5232 check_converting = false;
5234 strict = DEDUCE_CALL;
5235 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
5239 non_static_args = args;
5241 /* Delay creating the implicit this parameter until it is needed. */
5242 non_static_args = NULL;
5244 for (; fns; fns = OVL_NEXT (fns))
5247 const vec<tree, va_gc> *fn_args;
5249 fn = OVL_CURRENT (fns);
5251 if (check_converting && DECL_NONCONVERTING_P (fn))
5253 if (check_list_ctor && !is_list_ctor (fn))
5256 /* Figure out which set of arguments to use. */
5257 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
5259 /* If this function is a non-static member and we didn't get an
5260 implicit object argument, move it out of args. */
5261 if (first_arg == NULL_TREE)
5265 vec<tree, va_gc> *tempvec;
5266 vec_alloc (tempvec, args->length () - 1);
5267 for (ix = 1; args->iterate (ix, &arg); ++ix)
5268 tempvec->quick_push (arg);
5269 non_static_args = tempvec;
5270 first_arg = (*args)[0];
5273 fn_first_arg = first_arg;
5274 fn_args = non_static_args;
5278 /* Otherwise, just use the list of arguments provided. */
5279 fn_first_arg = NULL_TREE;
5283 if (TREE_CODE (fn) == TEMPLATE_DECL)
5284 add_template_candidate (candidates,
5296 else if (!template_only)
5297 add_function_candidate (candidates,
5310 build_new_op_1 (location_t loc, enum tree_code code, int flags, tree arg1,
5311 tree arg2, tree arg3, tree *overload, tsubst_flags_t complain)
5313 struct z_candidate *candidates = 0, *cand;
5314 vec<tree, va_gc> *arglist;
5317 tree result = NULL_TREE;
5318 bool result_valid_p = false;
5319 enum tree_code code2 = NOP_EXPR;
5320 enum tree_code code_orig_arg1 = ERROR_MARK;
5321 enum tree_code code_orig_arg2 = ERROR_MARK;
5327 if (error_operand_p (arg1)
5328 || error_operand_p (arg2)
5329 || error_operand_p (arg3))
5330 return error_mark_node;
5332 if (code == MODIFY_EXPR)
5334 code2 = TREE_CODE (arg3);
5336 fnname = ansi_assopname (code2);
5339 fnname = ansi_opname (code);
5341 arg1 = prep_operand (arg1);
5343 bool memonly = false;
5348 case VEC_DELETE_EXPR:
5350 /* Use build_op_new_call and build_op_delete_call instead. */
5354 /* Use build_op_call instead. */
5357 case TRUTH_ORIF_EXPR:
5358 case TRUTH_ANDIF_EXPR:
5359 case TRUTH_AND_EXPR:
5361 /* These are saved for the sake of warn_logical_operator. */
5362 code_orig_arg1 = TREE_CODE (arg1);
5363 code_orig_arg2 = TREE_CODE (arg2);
5371 /* These are saved for the sake of maybe_warn_bool_compare. */
5372 code_orig_arg1 = TREE_CODE (TREE_TYPE (arg1));
5373 code_orig_arg2 = TREE_CODE (TREE_TYPE (arg2));
5376 /* =, ->, [], () must be non-static member functions. */
5378 if (code2 != NOP_EXPR)
5389 arg2 = prep_operand (arg2);
5390 arg3 = prep_operand (arg3);
5392 if (code == COND_EXPR)
5393 /* Use build_conditional_expr instead. */
5395 else if (! OVERLOAD_TYPE_P (TREE_TYPE (arg1))
5396 && (! arg2 || ! OVERLOAD_TYPE_P (TREE_TYPE (arg2))))
5399 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
5400 arg2 = integer_zero_node;
5402 vec_alloc (arglist, 3);
5403 arglist->quick_push (arg1);
5404 if (arg2 != NULL_TREE)
5405 arglist->quick_push (arg2);
5406 if (arg3 != NULL_TREE)
5407 arglist->quick_push (arg3);
5409 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5410 p = conversion_obstack_alloc (0);
5412 /* Add namespace-scope operators to the list of functions to
5415 add_candidates (lookup_function_nonclass (fnname, arglist,
5417 NULL_TREE, arglist, NULL_TREE,
5418 NULL_TREE, false, NULL_TREE, NULL_TREE,
5419 flags, &candidates, complain);
5423 args[2] = NULL_TREE;
5425 /* Add class-member operators to the candidate set. */
5426 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
5430 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
5431 if (fns == error_mark_node)
5433 result = error_mark_node;
5434 goto user_defined_result_ready;
5437 add_candidates (BASELINK_FUNCTIONS (fns),
5438 NULL_TREE, arglist, NULL_TREE,
5440 BASELINK_BINFO (fns),
5441 BASELINK_ACCESS_BINFO (fns),
5442 flags, &candidates, complain);
5444 /* Per 13.3.1.2/3, 2nd bullet, if no operand has a class type, then
5445 only non-member functions that have type T1 or reference to
5446 cv-qualified-opt T1 for the first argument, if the first argument
5447 has an enumeration type, or T2 or reference to cv-qualified-opt
5448 T2 for the second argument, if the the second argument has an
5449 enumeration type. Filter out those that don't match. */
5450 else if (! arg2 || ! CLASS_TYPE_P (TREE_TYPE (arg2)))
5452 struct z_candidate **candp, **next;
5454 for (candp = &candidates; *candp; candp = next)
5456 tree parmlist, parmtype;
5457 int i, nargs = (arg2 ? 2 : 1);
5462 parmlist = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
5464 for (i = 0; i < nargs; ++i)
5466 parmtype = TREE_VALUE (parmlist);
5468 if (TREE_CODE (parmtype) == REFERENCE_TYPE)
5469 parmtype = TREE_TYPE (parmtype);
5470 if (TREE_CODE (TREE_TYPE (args[i])) == ENUMERAL_TYPE
5471 && (same_type_ignoring_top_level_qualifiers_p
5472 (TREE_TYPE (args[i]), parmtype)))
5475 parmlist = TREE_CHAIN (parmlist);
5478 /* No argument has an appropriate type, so remove this
5479 candidate function from the list. */
5482 *candp = cand->next;
5488 add_builtin_candidates (&candidates, code, code2, fnname, args,
5495 /* For these, the built-in candidates set is empty
5496 [over.match.oper]/3. We don't want non-strict matches
5497 because exact matches are always possible with built-in
5498 operators. The built-in candidate set for COMPONENT_REF
5499 would be empty too, but since there are no such built-in
5500 operators, we accept non-strict matches for them. */
5509 candidates = splice_viable (candidates, strict_p, &any_viable_p);
5514 case POSTINCREMENT_EXPR:
5515 case POSTDECREMENT_EXPR:
5516 /* Don't try anything fancy if we're not allowed to produce
5518 if (!(complain & tf_error))
5519 return error_mark_node;
5521 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
5522 distinguish between prefix and postfix ++ and
5523 operator++() was used for both, so we allow this with
5527 const char *msg = (flag_permissive)
5528 ? G_("no %<%D(int)%> declared for postfix %qs,"
5529 " trying prefix operator instead")
5530 : G_("no %<%D(int)%> declared for postfix %qs");
5531 permerror (loc, msg, fnname, operator_name_info[code].name);
5534 if (!flag_permissive)
5535 return error_mark_node;
5537 if (code == POSTINCREMENT_EXPR)
5538 code = PREINCREMENT_EXPR;
5540 code = PREDECREMENT_EXPR;
5541 result = build_new_op_1 (loc, code, flags, arg1, NULL_TREE,
5542 NULL_TREE, overload, complain);
5545 /* The caller will deal with these. */
5550 result_valid_p = true;
5554 if (complain & tf_error)
5556 /* If one of the arguments of the operator represents
5557 an invalid use of member function pointer, try to report
5558 a meaningful error ... */
5559 if (invalid_nonstatic_memfn_p (arg1, tf_error)
5560 || invalid_nonstatic_memfn_p (arg2, tf_error)
5561 || invalid_nonstatic_memfn_p (arg3, tf_error))
5562 /* We displayed the error message. */;
5565 /* ... Otherwise, report the more generic
5566 "no matching operator found" error */
5567 op_error (loc, code, code2, arg1, arg2, arg3, FALSE);
5568 print_z_candidates (loc, candidates);
5571 result = error_mark_node;
5577 cand = tourney (candidates, complain);
5580 if (complain & tf_error)
5582 op_error (loc, code, code2, arg1, arg2, arg3, TRUE);
5583 print_z_candidates (loc, candidates);
5585 result = error_mark_node;
5587 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
5590 *overload = cand->fn;
5592 if (resolve_args (arglist, complain) == NULL)
5593 result = error_mark_node;
5595 result = build_over_call (cand, LOOKUP_NORMAL, complain);
5599 /* Give any warnings we noticed during overload resolution. */
5600 if (cand->warnings && (complain & tf_warning))
5602 struct candidate_warning *w;
5603 for (w = cand->warnings; w; w = w->next)
5604 joust (cand, w->loser, 1, complain);
5607 /* Check for comparison of different enum types. */
5616 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
5617 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
5618 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
5619 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2)))
5620 && (complain & tf_warning))
5622 warning (OPT_Wenum_compare,
5623 "comparison between %q#T and %q#T",
5624 TREE_TYPE (arg1), TREE_TYPE (arg2));
5631 /* We need to strip any leading REF_BIND so that bitfields
5632 don't cause errors. This should not remove any important
5633 conversions, because builtins don't apply to class
5634 objects directly. */
5635 conv = cand->convs[0];
5636 if (conv->kind == ck_ref_bind)
5637 conv = next_conversion (conv);
5638 arg1 = convert_like (conv, arg1, complain);
5642 conv = cand->convs[1];
5643 if (conv->kind == ck_ref_bind)
5644 conv = next_conversion (conv);
5646 arg2 = decay_conversion (arg2, complain);
5648 /* We need to call warn_logical_operator before
5649 converting arg2 to a boolean_type, but after
5650 decaying an enumerator to its value. */
5651 if (complain & tf_warning)
5652 warn_logical_operator (loc, code, boolean_type_node,
5653 code_orig_arg1, arg1,
5654 code_orig_arg2, arg2);
5656 arg2 = convert_like (conv, arg2, complain);
5660 conv = cand->convs[2];
5661 if (conv->kind == ck_ref_bind)
5662 conv = next_conversion (conv);
5663 arg3 = convert_like (conv, arg3, complain);
5669 user_defined_result_ready:
5671 /* Free all the conversions we allocated. */
5672 obstack_free (&conversion_obstack, p);
5674 if (result || result_valid_p)
5681 return cp_build_modify_expr (arg1, code2, arg2, complain);
5684 return cp_build_indirect_ref (arg1, RO_UNARY_STAR, complain);
5686 case TRUTH_ANDIF_EXPR:
5687 case TRUTH_ORIF_EXPR:
5688 case TRUTH_AND_EXPR:
5690 if (complain & tf_warning)
5691 warn_logical_operator (loc, code, boolean_type_node,
5692 code_orig_arg1, arg1, code_orig_arg2, arg2);
5700 if ((complain & tf_warning)
5701 && ((code_orig_arg1 == BOOLEAN_TYPE)
5702 ^ (code_orig_arg2 == BOOLEAN_TYPE)))
5703 maybe_warn_bool_compare (loc, code, arg1, arg2);
5708 case TRUNC_DIV_EXPR:
5713 case TRUNC_MOD_EXPR:
5717 return cp_build_binary_op (loc, code, arg1, arg2, complain);
5719 case UNARY_PLUS_EXPR:
5722 case TRUTH_NOT_EXPR:
5723 case PREINCREMENT_EXPR:
5724 case POSTINCREMENT_EXPR:
5725 case PREDECREMENT_EXPR:
5726 case POSTDECREMENT_EXPR:
5730 return cp_build_unary_op (code, arg1, candidates != 0, complain);
5733 return cp_build_array_ref (input_location, arg1, arg2, complain);
5736 return build_m_component_ref (cp_build_indirect_ref (arg1, RO_ARROW_STAR,
5740 /* The caller will deal with these. */
5752 /* Wrapper for above. */
5755 build_new_op (location_t loc, enum tree_code code, int flags,
5756 tree arg1, tree arg2, tree arg3,
5757 tree *overload, tsubst_flags_t complain)
5760 bool subtime = timevar_cond_start (TV_OVERLOAD);
5761 ret = build_new_op_1 (loc, code, flags, arg1, arg2, arg3,
5762 overload, complain);
5763 timevar_cond_stop (TV_OVERLOAD, subtime);
5767 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
5768 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
5771 non_placement_deallocation_fn_p (tree t)
5773 /* A template instance is never a usual deallocation function,
5774 regardless of its signature. */
5775 if (TREE_CODE (t) == TEMPLATE_DECL
5776 || primary_template_instantiation_p (t))
5779 /* If a class T has a member deallocation function named operator delete
5780 with exactly one parameter, then that function is a usual
5781 (non-placement) deallocation function. If class T does not declare
5782 such an operator delete but does declare a member deallocation
5783 function named operator delete with exactly two parameters, the second
5784 of which has type std::size_t (18.2), then this function is a usual
5785 deallocation function. */
5786 bool global = DECL_NAMESPACE_SCOPE_P (t);
5787 t = FUNCTION_ARG_CHAIN (t);
5788 if (t == void_list_node
5789 || (t && same_type_p (TREE_VALUE (t), size_type_node)
5790 && (!global || flag_sized_deallocation)
5791 && TREE_CHAIN (t) == void_list_node))
5796 /* Build a call to operator delete. This has to be handled very specially,
5797 because the restrictions on what signatures match are different from all
5798 other call instances. For a normal delete, only a delete taking (void *)
5799 or (void *, size_t) is accepted. For a placement delete, only an exact
5800 match with the placement new is accepted.
5802 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
5803 ADDR is the pointer to be deleted.
5804 SIZE is the size of the memory block to be deleted.
5805 GLOBAL_P is true if the delete-expression should not consider
5806 class-specific delete operators.
5807 PLACEMENT is the corresponding placement new call, or NULL_TREE.
5809 If this call to "operator delete" is being generated as part to
5810 deallocate memory allocated via a new-expression (as per [expr.new]
5811 which requires that if the initialization throws an exception then
5812 we call a deallocation function), then ALLOC_FN is the allocation
5816 build_op_delete_call (enum tree_code code, tree addr, tree size,
5817 bool global_p, tree placement,
5818 tree alloc_fn, tsubst_flags_t complain)
5820 tree fn = NULL_TREE;
5821 tree fns, fnname, type, t;
5823 if (addr == error_mark_node)
5824 return error_mark_node;
5826 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
5828 fnname = ansi_opname (code);
5830 if (CLASS_TYPE_P (type)
5831 && COMPLETE_TYPE_P (complete_type (type))
5835 If the result of the lookup is ambiguous or inaccessible, or if
5836 the lookup selects a placement deallocation function, the
5837 program is ill-formed.
5839 Therefore, we ask lookup_fnfields to complain about ambiguity. */
5841 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
5842 if (fns == error_mark_node)
5843 return error_mark_node;
5848 if (fns == NULL_TREE)
5849 fns = lookup_name_nonclass (fnname);
5851 /* Strip const and volatile from addr. */
5852 addr = cp_convert (ptr_type_node, addr, complain);
5856 /* "A declaration of a placement deallocation function matches the
5857 declaration of a placement allocation function if it has the same
5858 number of parameters and, after parameter transformations (8.3.5),
5859 all parameter types except the first are identical."
5861 So we build up the function type we want and ask instantiate_type
5862 to get it for us. */
5863 t = FUNCTION_ARG_CHAIN (alloc_fn);
5864 t = tree_cons (NULL_TREE, ptr_type_node, t);
5865 t = build_function_type (void_type_node, t);
5867 fn = instantiate_type (t, fns, tf_none);
5868 if (fn == error_mark_node)
5871 if (BASELINK_P (fn))
5872 fn = BASELINK_FUNCTIONS (fn);
5874 /* "If the lookup finds the two-parameter form of a usual deallocation
5875 function (3.7.4.2) and that function, considered as a placement
5876 deallocation function, would have been selected as a match for the
5877 allocation function, the program is ill-formed." */
5878 if (non_placement_deallocation_fn_p (fn))
5880 /* But if the class has an operator delete (void *), then that is
5881 the usual deallocation function, so we shouldn't complain
5882 about using the operator delete (void *, size_t). */
5883 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5884 t; t = OVL_NEXT (t))
5886 tree elt = OVL_CURRENT (t);
5887 if (non_placement_deallocation_fn_p (elt)
5888 && FUNCTION_ARG_CHAIN (elt) == void_list_node)
5891 if (complain & tf_error)
5893 permerror (0, "non-placement deallocation function %q+D", fn);
5894 permerror (input_location, "selected for placement delete");
5897 return error_mark_node;
5902 /* "Any non-placement deallocation function matches a non-placement
5903 allocation function. If the lookup finds a single matching
5904 deallocation function, that function will be called; otherwise, no
5905 deallocation function will be called." */
5906 for (t = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
5907 t; t = OVL_NEXT (t))
5909 tree elt = OVL_CURRENT (t);
5910 if (non_placement_deallocation_fn_p (elt))
5913 /* "If a class T has a member deallocation function named
5914 operator delete with exactly one parameter, then that
5915 function is a usual (non-placement) deallocation
5916 function. If class T does not declare such an operator
5917 delete but does declare a member deallocation function named
5918 operator delete with exactly two parameters, the second of
5919 which has type std::size_t (18.2), then this function is a
5920 usual deallocation function."
5922 So in a class (void*) beats (void*, size_t). */
5923 if (DECL_CLASS_SCOPE_P (fn))
5925 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
5928 /* At global scope (in C++14 and above) the rules are different:
5930 If deallocation function lookup finds both a usual
5931 deallocation function with only a pointer parameter and a
5932 usual deallocation function with both a pointer parameter
5933 and a size parameter, the function to be called is selected
5936 * If the type is complete and if, for the second alternative
5937 (delete array) only, the operand is a pointer to a class
5938 type with a non-trivial destructor or a (possibly
5939 multi-dimensional) array thereof, the function with two
5940 parameters is selected.
5942 * Otherwise, it is unspecified which of the two deallocation
5943 functions is selected. */
5946 bool want_size = COMPLETE_TYPE_P (type);
5947 if (code == VEC_DELETE_EXPR
5948 && !TYPE_VEC_NEW_USES_COOKIE (type))
5949 /* We need a cookie to determine the array size. */
5951 bool have_size = (FUNCTION_ARG_CHAIN (fn) != void_list_node);
5952 if (want_size == have_size)
5958 /* If we have a matching function, call it. */
5961 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5963 /* If the FN is a member function, make sure that it is
5965 if (BASELINK_P (fns))
5966 perform_or_defer_access_check (BASELINK_BINFO (fns), fn, fn,
5969 /* Core issue 901: It's ok to new a type with deleted delete. */
5970 if (DECL_DELETED_FN (fn) && alloc_fn)
5975 /* The placement args might not be suitable for overload
5976 resolution at this point, so build the call directly. */
5977 int nargs = call_expr_nargs (placement);
5978 tree *argarray = XALLOCAVEC (tree, nargs);
5981 for (i = 1; i < nargs; i++)
5982 argarray[i] = CALL_EXPR_ARG (placement, i);
5984 return build_cxx_call (fn, nargs, argarray, complain);
5989 vec<tree, va_gc> *args = make_tree_vector ();
5990 args->quick_push (addr);
5991 if (FUNCTION_ARG_CHAIN (fn) != void_list_node)
5992 args->quick_push (size);
5993 ret = cp_build_function_call_vec (fn, &args, complain);
5994 release_tree_vector (args);
6001 If no unambiguous matching deallocation function can be found,
6002 propagating the exception does not cause the object's memory to
6006 if ((complain & tf_warning)
6008 warning (0, "no corresponding deallocation function for %qD",
6013 if (complain & tf_error)
6014 error ("no suitable %<operator %s%> for %qT",
6015 operator_name_info[(int)code].name, type);
6016 return error_mark_node;
6019 /* If the current scope isn't allowed to access DECL along
6020 BASETYPE_PATH, give an error. The most derived class in
6021 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
6022 the declaration to use in the error diagnostic. */
6025 enforce_access (tree basetype_path, tree decl, tree diag_decl,
6026 tsubst_flags_t complain)
6028 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
6030 if (!accessible_p (basetype_path, decl, true))
6032 if (complain & tf_error)
6034 if (TREE_PRIVATE (decl))
6035 error ("%q+#D is private", diag_decl);
6036 else if (TREE_PROTECTED (decl))
6037 error ("%q+#D is protected", diag_decl);
6039 error ("%q+#D is inaccessible", diag_decl);
6040 error ("within this context");
6048 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
6049 bitwise or of LOOKUP_* values. If any errors are warnings are
6050 generated, set *DIAGNOSTIC_FN to "error" or "warning",
6051 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
6055 build_temp (tree expr, tree type, int flags,
6056 diagnostic_t *diagnostic_kind, tsubst_flags_t complain)
6059 vec<tree, va_gc> *args;
6061 savew = warningcount + werrorcount, savee = errorcount;
6062 args = make_tree_vector_single (expr);
6063 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6064 &args, type, flags, complain);
6065 release_tree_vector (args);
6066 if (warningcount + werrorcount > savew)
6067 *diagnostic_kind = DK_WARNING;
6068 else if (errorcount > savee)
6069 *diagnostic_kind = DK_ERROR;
6071 *diagnostic_kind = DK_UNSPECIFIED;
6075 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
6076 EXPR is implicitly converted to type TOTYPE.
6077 FN and ARGNUM are used for diagnostics. */
6080 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
6082 /* Issue warnings about peculiar, but valid, uses of NULL. */
6083 if (expr == null_node && TREE_CODE (totype) != BOOLEAN_TYPE
6084 && ARITHMETIC_TYPE_P (totype))
6086 source_location loc =
6087 expansion_point_location_if_in_system_header (input_location);
6090 warning_at (loc, OPT_Wconversion_null,
6091 "passing NULL to non-pointer argument %P of %qD",
6094 warning_at (loc, OPT_Wconversion_null,
6095 "converting to non-pointer type %qT from NULL", totype);
6098 /* Issue warnings if "false" is converted to a NULL pointer */
6099 else if (TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE
6100 && TYPE_PTR_P (totype))
6103 warning_at (input_location, OPT_Wconversion_null,
6104 "converting %<false%> to pointer type for argument %P "
6105 "of %qD", argnum, fn);
6107 warning_at (input_location, OPT_Wconversion_null,
6108 "converting %<false%> to pointer type %qT", totype);
6112 /* We gave a diagnostic during a conversion. If this was in the second
6113 standard conversion sequence of a user-defined conversion sequence, say
6114 which user-defined conversion. */
6117 maybe_print_user_conv_context (conversion *convs)
6119 if (convs->user_conv_p)
6120 for (conversion *t = convs; t; t = next_conversion (t))
6121 if (t->kind == ck_user)
6123 print_z_candidate (0, " after user-defined conversion:",
6129 /* Perform the conversions in CONVS on the expression EXPR. FN and
6130 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
6131 indicates the `this' argument of a method. INNER is nonzero when
6132 being called to continue a conversion chain. It is negative when a
6133 reference binding will be applied, positive otherwise. If
6134 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
6135 conversions will be emitted if appropriate. If C_CAST_P is true,
6136 this conversion is coming from a C-style cast; in that case,
6137 conversions to inaccessible bases are permitted. */
6140 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
6141 int inner, bool issue_conversion_warnings,
6142 bool c_cast_p, tsubst_flags_t complain)
6144 tree totype = convs->type;
6145 diagnostic_t diag_kind;
6147 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
6149 if (convs->bad_p && !(complain & tf_error))
6150 return error_mark_node;
6153 && convs->kind != ck_user
6154 && convs->kind != ck_list
6155 && convs->kind != ck_ambig
6156 && (convs->kind != ck_ref_bind
6157 || (convs->user_conv_p && next_conversion (convs)->bad_p))
6158 && (convs->kind != ck_rvalue
6159 || SCALAR_TYPE_P (totype))
6160 && convs->kind != ck_base)
6162 bool complained = false;
6163 conversion *t = convs;
6165 /* Give a helpful error if this is bad because of excess braces. */
6166 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
6167 && SCALAR_TYPE_P (totype)
6168 && CONSTRUCTOR_NELTS (expr) > 0
6169 && BRACE_ENCLOSED_INITIALIZER_P (CONSTRUCTOR_ELT (expr, 0)->value))
6171 complained = permerror (loc, "too many braces around initializer "
6173 while (BRACE_ENCLOSED_INITIALIZER_P (expr)
6174 && CONSTRUCTOR_NELTS (expr) == 1)
6175 expr = CONSTRUCTOR_ELT (expr, 0)->value;
6178 /* Give a helpful error if this is bad because a conversion to bool
6179 from std::nullptr_t requires direct-initialization. */
6180 if (NULLPTR_TYPE_P (TREE_TYPE (expr))
6181 && TREE_CODE (totype) == BOOLEAN_TYPE)
6182 complained = permerror (loc, "converting to %qT from %qT requires "
6183 "direct-initialization",
6184 totype, TREE_TYPE (expr));
6186 for (; t ; t = next_conversion (t))
6188 if (t->kind == ck_user && t->cand->reason)
6190 complained = permerror (loc, "invalid user-defined conversion "
6191 "from %qT to %qT", TREE_TYPE (expr),
6194 print_z_candidate (loc, "candidate is:", t->cand);
6195 expr = convert_like_real (t, expr, fn, argnum, 1,
6196 /*issue_conversion_warnings=*/false,
6199 if (convs->kind == ck_ref_bind)
6200 expr = convert_to_reference (totype, expr, CONV_IMPLICIT,
6201 LOOKUP_NORMAL, NULL_TREE,
6204 expr = cp_convert (totype, expr, complain);
6205 if (complained && fn)
6206 inform (DECL_SOURCE_LOCATION (fn),
6207 " initializing argument %P of %qD", argnum, fn);
6210 else if (t->kind == ck_user || !t->bad_p)
6212 expr = convert_like_real (t, expr, fn, argnum, 1,
6213 /*issue_conversion_warnings=*/false,
6218 else if (t->kind == ck_ambig)
6219 return convert_like_real (t, expr, fn, argnum, 1,
6220 /*issue_conversion_warnings=*/false,
6223 else if (t->kind == ck_identity)
6227 complained = permerror (loc, "invalid conversion from %qT to %qT",
6228 TREE_TYPE (expr), totype);
6229 if (complained && fn)
6230 inform (DECL_SOURCE_LOCATION (fn),
6231 " initializing argument %P of %qD", argnum, fn);
6233 return cp_convert (totype, expr, complain);
6236 if (issue_conversion_warnings && (complain & tf_warning))
6237 conversion_null_warnings (totype, expr, fn, argnum);
6239 switch (convs->kind)
6243 struct z_candidate *cand = convs->cand;
6244 tree convfn = cand->fn;
6247 /* When converting from an init list we consider explicit
6248 constructors, but actually trying to call one is an error. */
6249 if (DECL_NONCONVERTING_P (convfn) && DECL_CONSTRUCTOR_P (convfn)
6250 /* Unless this is for direct-list-initialization. */
6251 && !DIRECT_LIST_INIT_P (expr))
6253 if (!(complain & tf_error))
6254 return error_mark_node;
6255 error ("converting to %qT from initializer list would use "
6256 "explicit constructor %qD", totype, convfn);
6259 /* If we're initializing from {}, it's value-initialization. */
6260 if (BRACE_ENCLOSED_INITIALIZER_P (expr)
6261 && CONSTRUCTOR_NELTS (expr) == 0
6262 && TYPE_HAS_DEFAULT_CONSTRUCTOR (totype))
6264 bool direct = CONSTRUCTOR_IS_DIRECT_INIT (expr);
6265 expr = build_value_init (totype, complain);
6266 expr = get_target_expr_sfinae (expr, complain);
6267 if (expr != error_mark_node)
6269 TARGET_EXPR_LIST_INIT_P (expr) = true;
6270 TARGET_EXPR_DIRECT_INIT_P (expr) = direct;
6275 expr = mark_rvalue_use (expr);
6277 /* Set user_conv_p on the argument conversions, so rvalue/base
6278 handling knows not to allow any more UDCs. */
6279 for (i = 0; i < cand->num_convs; ++i)
6280 cand->convs[i]->user_conv_p = true;
6282 expr = build_over_call (cand, LOOKUP_NORMAL, complain);
6284 /* If this is a constructor or a function returning an aggr type,
6285 we need to build up a TARGET_EXPR. */
6286 if (DECL_CONSTRUCTOR_P (convfn))
6288 expr = build_cplus_new (totype, expr, complain);
6290 /* Remember that this was list-initialization. */
6291 if (convs->check_narrowing && expr != error_mark_node)
6292 TARGET_EXPR_LIST_INIT_P (expr) = true;
6298 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
6300 int nelts = CONSTRUCTOR_NELTS (expr);
6302 expr = build_value_init (totype, complain);
6303 else if (nelts == 1)
6304 expr = CONSTRUCTOR_ELT (expr, 0)->value;
6308 expr = mark_rvalue_use (expr);
6310 if (type_unknown_p (expr))
6311 expr = instantiate_type (totype, expr, complain);
6312 /* Convert a constant to its underlying value, unless we are
6313 about to bind it to a reference, in which case we need to
6314 leave it as an lvalue. */
6317 expr = scalar_constant_value (expr);
6318 if (expr == null_node && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (totype))
6319 /* If __null has been converted to an integer type, we do not
6320 want to warn about uses of EXPR as an integer, rather than
6322 expr = build_int_cst (totype, 0);
6326 /* We leave bad_p off ck_ambig because overload resolution considers
6327 it valid, it just fails when we try to perform it. So we need to
6328 check complain here, too. */
6329 if (complain & tf_error)
6331 /* Call build_user_type_conversion again for the error. */
6332 build_user_type_conversion (totype, convs->u.expr, LOOKUP_NORMAL,
6335 inform (input_location, " initializing argument %P of %q+D",
6338 return error_mark_node;
6342 /* Conversion to std::initializer_list<T>. */
6343 tree elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (totype), 0);
6344 tree new_ctor = build_constructor (init_list_type_node, NULL);
6345 unsigned len = CONSTRUCTOR_NELTS (expr);
6346 tree array, val, field;
6347 vec<constructor_elt, va_gc> *vec = NULL;
6350 /* Convert all the elements. */
6351 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expr), ix, val)
6353 tree sub = convert_like_real (convs->u.list[ix], val, fn, argnum,
6354 1, false, false, complain);
6355 if (sub == error_mark_node)
6357 if (!BRACE_ENCLOSED_INITIALIZER_P (val)
6358 && !check_narrowing (TREE_TYPE (sub), val, complain))
6359 return error_mark_node;
6360 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_ctor), NULL_TREE, sub);
6361 if (!TREE_CONSTANT (sub))
6362 TREE_CONSTANT (new_ctor) = false;
6364 /* Build up the array. */
6365 elttype = cp_build_qualified_type
6366 (elttype, cp_type_quals (elttype) | TYPE_QUAL_CONST);
6367 array = build_array_of_n_type (elttype, len);
6368 array = finish_compound_literal (array, new_ctor, complain);
6369 /* Take the address explicitly rather than via decay_conversion
6370 to avoid the error about taking the address of a temporary. */
6371 array = cp_build_addr_expr (array, complain);
6372 array = cp_convert (build_pointer_type (elttype), array, complain);
6373 if (array == error_mark_node)
6374 return error_mark_node;
6376 /* Build up the initializer_list object. */
6377 totype = complete_type (totype);
6378 field = next_initializable_field (TYPE_FIELDS (totype));
6379 CONSTRUCTOR_APPEND_ELT (vec, field, array);
6380 field = next_initializable_field (DECL_CHAIN (field));
6381 CONSTRUCTOR_APPEND_ELT (vec, field, size_int (len));
6382 new_ctor = build_constructor (totype, vec);
6383 return get_target_expr_sfinae (new_ctor, complain);
6387 if (TREE_CODE (totype) == COMPLEX_TYPE)
6389 tree real = CONSTRUCTOR_ELT (expr, 0)->value;
6390 tree imag = CONSTRUCTOR_ELT (expr, 1)->value;
6391 real = perform_implicit_conversion (TREE_TYPE (totype),
6393 imag = perform_implicit_conversion (TREE_TYPE (totype),
6395 expr = build2 (COMPLEX_EXPR, totype, real, imag);
6396 return fold_if_not_in_template (expr);
6398 expr = reshape_init (totype, expr, complain);
6399 expr = get_target_expr_sfinae (digest_init (totype, expr, complain),
6401 if (expr != error_mark_node)
6402 TARGET_EXPR_LIST_INIT_P (expr) = true;
6409 expr = convert_like_real (next_conversion (convs), expr, fn, argnum,
6410 convs->kind == ck_ref_bind ? -1 : 1,
6411 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
6414 if (expr == error_mark_node)
6415 return error_mark_node;
6417 switch (convs->kind)
6420 expr = decay_conversion (expr, complain);
6421 if (expr == error_mark_node)
6422 return error_mark_node;
6424 if (! MAYBE_CLASS_TYPE_P (totype))
6426 /* Else fall through. */
6428 if (convs->kind == ck_base && !convs->need_temporary_p)
6430 /* We are going to bind a reference directly to a base-class
6431 subobject of EXPR. */
6432 /* Build an expression for `*((base*) &expr)'. */
6433 expr = convert_to_base (expr, totype,
6434 !c_cast_p, /*nonnull=*/true, complain);
6438 /* Copy-initialization where the cv-unqualified version of the source
6439 type is the same class as, or a derived class of, the class of the
6440 destination [is treated as direct-initialization]. [dcl.init] */
6441 flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
6442 if (convs->user_conv_p)
6443 /* This conversion is being done in the context of a user-defined
6444 conversion (i.e. the second step of copy-initialization), so
6445 don't allow any more. */
6446 flags |= LOOKUP_NO_CONVERSION;
6447 if (convs->rvaluedness_matches_p)
6448 flags |= LOOKUP_PREFER_RVALUE;
6449 if (TREE_CODE (expr) == TARGET_EXPR
6450 && TARGET_EXPR_LIST_INIT_P (expr))
6451 /* Copy-list-initialization doesn't actually involve a copy. */
6453 expr = build_temp (expr, totype, flags, &diag_kind, complain);
6454 if (diag_kind && complain)
6456 maybe_print_user_conv_context (convs);
6458 inform (DECL_SOURCE_LOCATION (fn),
6459 " initializing argument %P of %qD", argnum, fn);
6462 return build_cplus_new (totype, expr, complain);
6466 tree ref_type = totype;
6468 if (convs->bad_p && !next_conversion (convs)->bad_p)
6470 tree extype = TREE_TYPE (expr);
6471 if (TYPE_REF_IS_RVALUE (ref_type)
6472 && real_lvalue_p (expr))
6473 error_at (loc, "cannot bind %qT lvalue to %qT",
6475 else if (!TYPE_REF_IS_RVALUE (ref_type) && !real_lvalue_p (expr)
6476 && !CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
6477 error_at (loc, "invalid initialization of non-const reference of "
6478 "type %qT from an rvalue of type %qT", totype, extype);
6479 else if (!reference_compatible_p (TREE_TYPE (totype), extype))
6480 error_at (loc, "binding %qT to reference of type %qT "
6481 "discards qualifiers", extype, totype);
6484 maybe_print_user_conv_context (convs);
6486 inform (input_location,
6487 " initializing argument %P of %q+D", argnum, fn);
6488 return error_mark_node;
6491 /* If necessary, create a temporary.
6493 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
6494 that need temporaries, even when their types are reference
6495 compatible with the type of reference being bound, so the
6496 upcoming call to cp_build_addr_expr doesn't fail. */
6497 if (convs->need_temporary_p
6498 || TREE_CODE (expr) == CONSTRUCTOR
6499 || TREE_CODE (expr) == VA_ARG_EXPR)
6501 /* Otherwise, a temporary of type "cv1 T1" is created and
6502 initialized from the initializer expression using the rules
6503 for a non-reference copy-initialization (8.5). */
6505 tree type = TREE_TYPE (ref_type);
6506 cp_lvalue_kind lvalue = real_lvalue_p (expr);
6508 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6509 (type, next_conversion (convs)->type));
6510 if (!CP_TYPE_CONST_NON_VOLATILE_P (type)
6511 && !TYPE_REF_IS_RVALUE (ref_type))
6513 /* If the reference is volatile or non-const, we
6514 cannot create a temporary. */
6515 if (lvalue & clk_bitfield)
6516 error_at (loc, "cannot bind bitfield %qE to %qT",
6518 else if (lvalue & clk_packed)
6519 error_at (loc, "cannot bind packed field %qE to %qT",
6522 error_at (loc, "cannot bind rvalue %qE to %qT",
6524 return error_mark_node;
6526 /* If the source is a packed field, and we must use a copy
6527 constructor, then building the target expr will require
6528 binding the field to the reference parameter to the
6529 copy constructor, and we'll end up with an infinite
6530 loop. If we can use a bitwise copy, then we'll be
6532 if ((lvalue & clk_packed)
6533 && CLASS_TYPE_P (type)
6534 && type_has_nontrivial_copy_init (type))
6536 error_at (loc, "cannot bind packed field %qE to %qT",
6538 return error_mark_node;
6540 if (lvalue & clk_bitfield)
6542 expr = convert_bitfield_to_declared_type (expr);
6543 expr = fold_convert (type, expr);
6545 expr = build_target_expr_with_type (expr, type, complain);
6548 /* Take the address of the thing to which we will bind the
6550 expr = cp_build_addr_expr (expr, complain);
6551 if (expr == error_mark_node)
6552 return error_mark_node;
6554 /* Convert it to a pointer to the type referred to by the
6555 reference. This will adjust the pointer if a derived to
6556 base conversion is being performed. */
6557 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
6559 /* Convert the pointer to the desired reference type. */
6560 return build_nop (ref_type, expr);
6564 return decay_conversion (expr, complain);
6567 /* Warn about deprecated conversion if appropriate. */
6568 string_conv_p (totype, expr, 1);
6573 expr = convert_to_base (expr, totype, !c_cast_p,
6574 /*nonnull=*/false, complain);
6575 return build_nop (totype, expr);
6578 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
6579 c_cast_p, complain);
6585 if (convs->check_narrowing
6586 && !check_narrowing (totype, expr, complain))
6587 return error_mark_node;
6589 if (issue_conversion_warnings)
6590 expr = cp_convert_and_check (totype, expr, complain);
6592 expr = cp_convert (totype, expr, complain);
6597 /* ARG is being passed to a varargs function. Perform any conversions
6598 required. Return the converted value. */
6601 convert_arg_to_ellipsis (tree arg, tsubst_flags_t complain)
6604 location_t loc = EXPR_LOC_OR_LOC (arg, input_location);
6608 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6609 standard conversions are performed. */
6610 arg = decay_conversion (arg, complain);
6611 arg_type = TREE_TYPE (arg);
6614 If the argument has integral or enumeration type that is subject
6615 to the integral promotions (_conv.prom_), or a floating point
6616 type that is subject to the floating point promotion
6617 (_conv.fpprom_), the value of the argument is converted to the
6618 promoted type before the call. */
6619 if (TREE_CODE (arg_type) == REAL_TYPE
6620 && (TYPE_PRECISION (arg_type)
6621 < TYPE_PRECISION (double_type_node))
6622 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (arg_type)))
6624 if ((complain & tf_warning)
6625 && warn_double_promotion && !c_inhibit_evaluation_warnings)
6626 warning_at (loc, OPT_Wdouble_promotion,
6627 "implicit conversion from %qT to %qT when passing "
6628 "argument to function",
6629 arg_type, double_type_node);
6630 arg = convert_to_real (double_type_node, arg);
6632 else if (NULLPTR_TYPE_P (arg_type))
6633 arg = null_pointer_node;
6634 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (arg_type))
6636 if (SCOPED_ENUM_P (arg_type))
6638 tree prom = cp_convert (ENUM_UNDERLYING_TYPE (arg_type), arg,
6640 prom = cp_perform_integral_promotions (prom, complain);
6641 if (abi_version_crosses (6)
6642 && TYPE_MODE (TREE_TYPE (prom)) != TYPE_MODE (arg_type)
6643 && (complain & tf_warning))
6644 warning_at (loc, OPT_Wabi, "scoped enum %qT passed through ... as "
6645 "%qT before -fabi-version=6, %qT after", arg_type,
6646 TREE_TYPE (prom), ENUM_UNDERLYING_TYPE (arg_type));
6647 if (!abi_version_at_least (6))
6651 arg = cp_perform_integral_promotions (arg, complain);
6654 arg = require_complete_type_sfinae (arg, complain);
6655 arg_type = TREE_TYPE (arg);
6657 if (arg != error_mark_node
6658 /* In a template (or ill-formed code), we can have an incomplete type
6659 even after require_complete_type_sfinae, in which case we don't know
6660 whether it has trivial copy or not. */
6661 && COMPLETE_TYPE_P (arg_type))
6663 /* Build up a real lvalue-to-rvalue conversion in case the
6664 copy constructor is trivial but not callable. */
6665 if (!cp_unevaluated_operand && CLASS_TYPE_P (arg_type))
6666 force_rvalue (arg, complain);
6668 /* [expr.call] 5.2.2/7:
6669 Passing a potentially-evaluated argument of class type (Clause 9)
6670 with a non-trivial copy constructor or a non-trivial destructor
6671 with no corresponding parameter is conditionally-supported, with
6672 implementation-defined semantics.
6674 We support it as pass-by-invisible-reference, just like a normal
6677 If the call appears in the context of a sizeof expression,
6678 it is not potentially-evaluated. */
6679 if (cp_unevaluated_operand == 0
6680 && (type_has_nontrivial_copy_init (arg_type)
6681 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (arg_type)))
6683 if (complain & tf_warning)
6684 warning (OPT_Wconditionally_supported,
6685 "passing objects of non-trivially-copyable "
6686 "type %q#T through %<...%> is conditionally supported",
6688 return cp_build_addr_expr (arg, complain);
6695 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
6698 build_x_va_arg (source_location loc, tree expr, tree type)
6700 if (processing_template_decl)
6702 tree r = build_min (VA_ARG_EXPR, type, expr);
6703 SET_EXPR_LOCATION (r, loc);
6707 type = complete_type_or_else (type, NULL_TREE);
6709 if (expr == error_mark_node || !type)
6710 return error_mark_node;
6712 expr = mark_lvalue_use (expr);
6714 if (TREE_CODE (type) == REFERENCE_TYPE)
6716 error ("cannot receive reference type %qT through %<...%>", type);
6717 return error_mark_node;
6720 if (type_has_nontrivial_copy_init (type)
6721 || TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6723 /* conditionally-supported behavior [expr.call] 5.2.2/7. Let's treat
6724 it as pass by invisible reference. */
6725 warning_at (loc, OPT_Wconditionally_supported,
6726 "receiving objects of non-trivially-copyable type %q#T "
6727 "through %<...%> is conditionally-supported", type);
6729 tree ref = cp_build_reference_type (type, false);
6730 expr = build_va_arg (loc, expr, ref);
6731 return convert_from_reference (expr);
6734 return build_va_arg (loc, expr, type);
6737 /* TYPE has been given to va_arg. Apply the default conversions which
6738 would have happened when passed via ellipsis. Return the promoted
6739 type, or the passed type if there is no change. */
6742 cxx_type_promotes_to (tree type)
6746 /* Perform the array-to-pointer and function-to-pointer
6748 type = type_decays_to (type);
6750 promote = type_promotes_to (type);
6751 if (same_type_p (type, promote))
6757 /* ARG is a default argument expression being passed to a parameter of
6758 the indicated TYPE, which is a parameter to FN. PARMNUM is the
6759 zero-based argument number. Do any required conversions. Return
6760 the converted value. */
6762 static GTY(()) vec<tree, va_gc> *default_arg_context;
6764 push_defarg_context (tree fn)
6765 { vec_safe_push (default_arg_context, fn); }
6768 pop_defarg_context (void)
6769 { default_arg_context->pop (); }
6772 convert_default_arg (tree type, tree arg, tree fn, int parmnum,
6773 tsubst_flags_t complain)
6778 /* See through clones. */
6779 fn = DECL_ORIGIN (fn);
6781 /* Detect recursion. */
6782 FOR_EACH_VEC_SAFE_ELT (default_arg_context, i, t)
6785 if (complain & tf_error)
6786 error ("recursive evaluation of default argument for %q#D", fn);
6787 return error_mark_node;
6790 /* If the ARG is an unparsed default argument expression, the
6791 conversion cannot be performed. */
6792 if (TREE_CODE (arg) == DEFAULT_ARG)
6794 if (complain & tf_error)
6795 error ("call to %qD uses the default argument for parameter %P, which "
6796 "is not yet defined", fn, parmnum);
6797 return error_mark_node;
6800 push_defarg_context (fn);
6802 if (fn && DECL_TEMPLATE_INFO (fn))
6803 arg = tsubst_default_argument (fn, type, arg, complain);
6809 The names in the expression are bound, and the semantic
6810 constraints are checked, at the point where the default
6811 expressions appears.
6813 we must not perform access checks here. */
6814 push_deferring_access_checks (dk_no_check);
6815 /* We must make a copy of ARG, in case subsequent processing
6816 alters any part of it. */
6817 arg = break_out_target_exprs (arg);
6818 arg = convert_for_initialization (0, type, arg, LOOKUP_IMPLICIT,
6819 ICR_DEFAULT_ARGUMENT, fn, parmnum,
6821 arg = convert_for_arg_passing (type, arg, complain);
6822 pop_deferring_access_checks();
6824 pop_defarg_context ();
6829 /* Returns the type which will really be used for passing an argument of
6833 type_passed_as (tree type)
6835 /* Pass classes with copy ctors by invisible reference. */
6836 if (TREE_ADDRESSABLE (type))
6838 type = build_reference_type (type);
6839 /* There are no other pointers to this temporary. */
6840 type = cp_build_qualified_type (type, TYPE_QUAL_RESTRICT);
6842 else if (targetm.calls.promote_prototypes (type)
6843 && INTEGRAL_TYPE_P (type)
6844 && COMPLETE_TYPE_P (type)
6845 && tree_int_cst_lt (TYPE_SIZE (type), TYPE_SIZE (integer_type_node)))
6846 type = integer_type_node;
6851 /* Actually perform the appropriate conversion. */
6854 convert_for_arg_passing (tree type, tree val, tsubst_flags_t complain)
6858 /* If VAL is a bitfield, then -- since it has already been converted
6859 to TYPE -- it cannot have a precision greater than TYPE.
6861 If it has a smaller precision, we must widen it here. For
6862 example, passing "int f:3;" to a function expecting an "int" will
6863 not result in any conversion before this point.
6865 If the precision is the same we must not risk widening. For
6866 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
6867 often have type "int", even though the C++ type for the field is
6868 "long long". If the value is being passed to a function
6869 expecting an "int", then no conversions will be required. But,
6870 if we call convert_bitfield_to_declared_type, the bitfield will
6871 be converted to "long long". */
6872 bitfield_type = is_bitfield_expr_with_lowered_type (val);
6874 && TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type))
6875 val = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), val);
6877 if (val == error_mark_node)
6879 /* Pass classes with copy ctors by invisible reference. */
6880 else if (TREE_ADDRESSABLE (type))
6881 val = build1 (ADDR_EXPR, build_reference_type (type), val);
6882 else if (targetm.calls.promote_prototypes (type)
6883 && INTEGRAL_TYPE_P (type)
6884 && COMPLETE_TYPE_P (type)
6885 && tree_int_cst_lt (TYPE_SIZE (type), TYPE_SIZE (integer_type_node)))
6886 val = cp_perform_integral_promotions (val, complain);
6887 if ((complain & tf_warning)
6888 && warn_suggest_attribute_format)
6890 tree rhstype = TREE_TYPE (val);
6891 const enum tree_code coder = TREE_CODE (rhstype);
6892 const enum tree_code codel = TREE_CODE (type);
6893 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6895 && check_missing_format_attribute (type, rhstype))
6896 warning (OPT_Wsuggest_attribute_format,
6897 "argument of function call might be a candidate for a format attribute");
6902 /* Returns true iff FN is a function with magic varargs, i.e. ones for
6903 which no conversions at all should be done. This is true for some
6904 builtins which don't act like normal functions. */
6907 magic_varargs_p (tree fn)
6909 if (flag_cilkplus && is_cilkplus_reduce_builtin (fn) != BUILT_IN_NONE)
6912 if (DECL_BUILT_IN (fn))
6913 switch (DECL_FUNCTION_CODE (fn))
6915 case BUILT_IN_CLASSIFY_TYPE:
6916 case BUILT_IN_CONSTANT_P:
6917 case BUILT_IN_NEXT_ARG:
6918 case BUILT_IN_VA_START:
6922 return lookup_attribute ("type generic",
6923 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
6929 /* Returns the decl of the dispatcher function if FN is a function version. */
6932 get_function_version_dispatcher (tree fn)
6934 tree dispatcher_decl = NULL;
6936 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6937 && DECL_FUNCTION_VERSIONED (fn));
6939 gcc_assert (targetm.get_function_versions_dispatcher);
6940 dispatcher_decl = targetm.get_function_versions_dispatcher (fn);
6942 if (dispatcher_decl == NULL)
6944 error_at (input_location, "use of multiversioned function "
6945 "without a default");
6949 retrofit_lang_decl (dispatcher_decl);
6950 gcc_assert (dispatcher_decl != NULL);
6951 return dispatcher_decl;
6954 /* fn is a function version dispatcher that is marked used. Mark all the
6955 semantically identical function versions it will dispatch as used. */
6958 mark_versions_used (tree fn)
6960 struct cgraph_node *node;
6961 struct cgraph_function_version_info *node_v;
6962 struct cgraph_function_version_info *it_v;
6964 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6966 node = cgraph_node::get (fn);
6970 gcc_assert (node->dispatcher_function);
6972 node_v = node->function_version ();
6976 /* All semantically identical versions are chained. Traverse and mark each
6977 one of them as used. */
6978 it_v = node_v->next;
6979 while (it_v != NULL)
6981 mark_used (it_v->this_node->decl);
6986 /* Build a call to "the copy constructor" for the type of A, even if it
6987 wouldn't be selected by normal overload resolution. Used for
6991 call_copy_ctor (tree a, tsubst_flags_t complain)
6993 tree ctype = TYPE_MAIN_VARIANT (TREE_TYPE (a));
6994 tree binfo = TYPE_BINFO (ctype);
6995 tree copy = get_copy_ctor (ctype, complain);
6996 copy = build_baselink (binfo, binfo, copy, NULL_TREE);
6997 tree ob = build_dummy_object (ctype);
6998 vec<tree, va_gc>* args = make_tree_vector_single (a);
6999 tree r = build_new_method_call (ob, copy, &args, NULL_TREE,
7000 LOOKUP_NORMAL, NULL, complain);
7001 release_tree_vector (args);
7005 /* Return true iff T refers to a base field. */
7008 is_base_field_ref (tree t)
7011 if (TREE_CODE (t) == ADDR_EXPR)
7012 t = TREE_OPERAND (t, 0);
7013 if (TREE_CODE (t) == COMPONENT_REF)
7014 t = TREE_OPERAND (t, 1);
7015 if (TREE_CODE (t) == FIELD_DECL)
7016 return DECL_FIELD_IS_BASE (t);
7020 /* We can't elide a copy from a function returning by value to a base
7021 subobject, as the callee might clobber tail padding. Return true iff this
7022 could be that case. */
7025 unsafe_copy_elision_p (tree target, tree exp)
7027 tree type = TYPE_MAIN_VARIANT (TREE_TYPE (exp));
7028 if (type == CLASSTYPE_AS_BASE (type))
7030 if (!is_base_field_ref (target)
7031 && resolves_to_fixed_type_p (target, NULL))
7033 tree init = TARGET_EXPR_INITIAL (exp);
7034 return (TREE_CODE (init) == AGGR_INIT_EXPR
7035 && !AGGR_INIT_VIA_CTOR_P (init));
7038 /* Subroutine of the various build_*_call functions. Overload resolution
7039 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
7040 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
7041 bitmask of various LOOKUP_* flags which apply to the call itself. */
7044 build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
7047 const vec<tree, va_gc> *args = cand->args;
7048 tree first_arg = cand->first_arg;
7049 conversion **convs = cand->convs;
7051 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
7056 unsigned int arg_index = 0;
7060 bool already_used = false;
7062 /* In a template, there is no need to perform all of the work that
7063 is normally done. We are only interested in the type of the call
7064 expression, i.e., the return type of the function. Any semantic
7065 errors will be deferred until the template is instantiated. */
7066 if (processing_template_decl)
7070 const tree *argarray;
7073 return_type = TREE_TYPE (TREE_TYPE (fn));
7074 nargs = vec_safe_length (args);
7075 if (first_arg == NULL_TREE)
7076 argarray = args->address ();
7084 alcarray = XALLOCAVEC (tree, nargs);
7085 alcarray[0] = build_this (first_arg);
7086 FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
7087 alcarray[ix + 1] = arg;
7088 argarray = alcarray;
7091 addr = build_addr_func (fn, complain);
7092 if (addr == error_mark_node)
7093 return error_mark_node;
7094 expr = build_call_array_loc (input_location, return_type,
7095 addr, nargs, argarray);
7096 if (TREE_THIS_VOLATILE (fn) && cfun)
7097 current_function_returns_abnormally = 1;
7098 return convert_from_reference (expr);
7101 /* Give any warnings we noticed during overload resolution. */
7102 if (cand->warnings && (complain & tf_warning))
7104 struct candidate_warning *w;
7105 for (w = cand->warnings; w; w = w->next)
7106 joust (cand, w->loser, 1, complain);
7109 /* Make =delete work with SFINAE. */
7110 if (DECL_DELETED_FN (fn) && !(complain & tf_error))
7111 return error_mark_node;
7113 if (DECL_FUNCTION_MEMBER_P (fn))
7116 /* If FN is a template function, two cases must be considered.
7121 template <class T> void f();
7123 template <class T> struct B {
7127 struct C : A, B<int> {
7129 using B<int>::g; // #2
7132 In case #1 where `A::f' is a member template, DECL_ACCESS is
7133 recorded in the primary template but not in its specialization.
7134 We check access of FN using its primary template.
7136 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
7137 because it is a member of class template B, DECL_ACCESS is
7138 recorded in the specialization `B<int>::g'. We cannot use its
7139 primary template because `B<T>::g' and `B<int>::g' may have
7140 different access. */
7141 if (DECL_TEMPLATE_INFO (fn)
7142 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
7143 access_fn = DECL_TI_TEMPLATE (fn);
7146 if (!perform_or_defer_access_check (cand->access_path, access_fn,
7148 return error_mark_node;
7151 /* If we're checking for implicit delete, don't bother with argument
7153 if (flags & LOOKUP_SPECULATIVE)
7155 if (DECL_DELETED_FN (fn))
7157 if (complain & tf_error)
7159 return error_mark_node;
7161 if (cand->viable == 1)
7163 else if (!(complain & tf_error))
7164 /* Reject bad conversions now. */
7165 return error_mark_node;
7166 /* else continue to get conversion error. */
7169 /* N3276 magic doesn't apply to nested calls. */
7170 int decltype_flag = (complain & tf_decltype);
7171 complain &= ~tf_decltype;
7173 /* Find maximum size of vector to hold converted arguments. */
7174 parmlen = list_length (parm);
7175 nargs = vec_safe_length (args) + (first_arg != NULL_TREE ? 1 : 0);
7176 if (parmlen > nargs)
7178 argarray = XALLOCAVEC (tree, nargs);
7180 /* The implicit parameters to a constructor are not considered by overload
7181 resolution, and must be of the proper type. */
7182 if (DECL_CONSTRUCTOR_P (fn))
7185 if (first_arg != NULL_TREE)
7187 object_arg = first_arg;
7188 first_arg = NULL_TREE;
7192 object_arg = (*args)[arg_index];
7195 argarray[j++] = build_this (object_arg);
7196 parm = TREE_CHAIN (parm);
7197 /* We should never try to call the abstract constructor. */
7198 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
7200 if (DECL_HAS_VTT_PARM_P (fn))
7202 argarray[j++] = (*args)[arg_index];
7204 parm = TREE_CHAIN (parm);
7207 /* Bypass access control for 'this' parameter. */
7208 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
7210 tree parmtype = TREE_VALUE (parm);
7211 tree arg = build_this (first_arg != NULL_TREE
7213 : (*args)[arg_index]);
7214 tree argtype = TREE_TYPE (arg);
7218 if (convs[i]->bad_p)
7220 if (complain & tf_error)
7222 if (permerror (input_location, "passing %qT as %<this%> "
7223 "argument discards qualifiers",
7224 TREE_TYPE (argtype)))
7225 inform (DECL_SOURCE_LOCATION (fn), " in call to %qD", fn);
7228 return error_mark_node;
7231 /* See if the function member or the whole class type is declared
7232 final and the call can be devirtualized. */
7233 if (DECL_FINAL_P (fn)
7234 || CLASSTYPE_FINAL (TYPE_METHOD_BASETYPE (TREE_TYPE (fn))))
7235 flags |= LOOKUP_NONVIRTUAL;
7237 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
7238 X is called for an object that is not of type X, or of a type
7239 derived from X, the behavior is undefined.
7241 So we can assume that anything passed as 'this' is non-null, and
7242 optimize accordingly. */
7243 gcc_assert (TYPE_PTR_P (parmtype));
7244 /* Convert to the base in which the function was declared. */
7245 gcc_assert (cand->conversion_path != NULL_TREE);
7246 converted_arg = build_base_path (PLUS_EXPR,
7248 cand->conversion_path,
7250 /* Check that the base class is accessible. */
7251 if (!accessible_base_p (TREE_TYPE (argtype),
7252 BINFO_TYPE (cand->conversion_path), true))
7254 if (complain & tf_error)
7255 error ("%qT is not an accessible base of %qT",
7256 BINFO_TYPE (cand->conversion_path),
7257 TREE_TYPE (argtype));
7259 return error_mark_node;
7261 /* If fn was found by a using declaration, the conversion path
7262 will be to the derived class, not the base declaring fn. We
7263 must convert from derived to base. */
7264 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
7265 TREE_TYPE (parmtype), ba_unique,
7267 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
7268 base_binfo, 1, complain);
7270 argarray[j++] = converted_arg;
7271 parm = TREE_CHAIN (parm);
7272 if (first_arg != NULL_TREE)
7273 first_arg = NULL_TREE;
7280 gcc_assert (first_arg == NULL_TREE);
7281 for (; arg_index < vec_safe_length (args) && parm;
7282 parm = TREE_CHAIN (parm), ++arg_index, ++i)
7284 tree type = TREE_VALUE (parm);
7285 tree arg = (*args)[arg_index];
7286 bool conversion_warning = true;
7290 /* If the argument is NULL and used to (implicitly) instantiate a
7291 template function (and bind one of the template arguments to
7292 the type of 'long int'), we don't want to warn about passing NULL
7293 to non-pointer argument.
7294 For example, if we have this template function:
7296 template<typename T> void func(T x) {}
7298 we want to warn (when -Wconversion is enabled) in this case:
7304 but not in this case:
7310 if (arg == null_node
7311 && DECL_TEMPLATE_INFO (fn)
7312 && cand->template_decl
7313 && !(flags & LOOKUP_EXPLICIT_TMPL_ARGS))
7314 conversion_warning = false;
7316 /* Warn about initializer_list deduction that isn't currently in the
7318 if (cxx_dialect > cxx98
7319 && flag_deduce_init_list
7320 && cand->template_decl
7321 && is_std_init_list (non_reference (type))
7322 && BRACE_ENCLOSED_INITIALIZER_P (arg))
7324 tree tmpl = TI_TEMPLATE (cand->template_decl);
7325 tree realparm = chain_index (j, DECL_ARGUMENTS (cand->fn));
7326 tree patparm = get_pattern_parm (realparm, tmpl);
7327 tree pattype = TREE_TYPE (patparm);
7328 if (PACK_EXPANSION_P (pattype))
7329 pattype = PACK_EXPANSION_PATTERN (pattype);
7330 pattype = non_reference (pattype);
7332 if (TREE_CODE (pattype) == TEMPLATE_TYPE_PARM
7333 && (cand->explicit_targs == NULL_TREE
7334 || (TREE_VEC_LENGTH (cand->explicit_targs)
7335 <= TEMPLATE_TYPE_IDX (pattype))))
7337 pedwarn (input_location, 0, "deducing %qT as %qT",
7338 non_reference (TREE_TYPE (patparm)),
7339 non_reference (type));
7340 pedwarn (input_location, 0, " in call to %q+D", cand->fn);
7341 pedwarn (input_location, 0,
7342 " (you can disable this with -fno-deduce-init-list)");
7345 val = convert_like_with_context (conv, arg, fn, i - is_method,
7348 : complain & (~tf_warning));
7350 val = convert_for_arg_passing (type, val, complain);
7352 if (val == error_mark_node)
7353 return error_mark_node;
7355 argarray[j++] = val;
7358 /* Default arguments */
7359 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
7361 if (TREE_VALUE (parm) == error_mark_node)
7362 return error_mark_node;
7363 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
7364 TREE_PURPOSE (parm),
7370 for (; arg_index < vec_safe_length (args); ++arg_index)
7372 tree a = (*args)[arg_index];
7373 if (magic_varargs_p (fn))
7374 /* Do no conversions for magic varargs. */
7375 a = mark_type_use (a);
7376 else if (DECL_CONSTRUCTOR_P (fn)
7377 && same_type_ignoring_top_level_qualifiers_p (DECL_CONTEXT (fn),
7380 /* Avoid infinite recursion trying to call A(...). */
7381 if (complain & tf_error)
7382 /* Try to call the actual copy constructor for a good error. */
7383 call_copy_ctor (a, complain);
7384 return error_mark_node;
7387 a = convert_arg_to_ellipsis (a, complain);
7391 gcc_assert (j <= nargs);
7394 check_function_arguments (TREE_TYPE (fn), nargs, argarray);
7396 /* Avoid actually calling copy constructors and copy assignment operators,
7399 if (! flag_elide_constructors)
7400 /* Do things the hard way. */;
7401 else if (cand->num_convs == 1
7402 && (DECL_COPY_CONSTRUCTOR_P (fn)
7403 || DECL_MOVE_CONSTRUCTOR_P (fn))
7404 /* It's unsafe to elide the constructor when handling
7405 a noexcept-expression, it may evaluate to the wrong
7406 value (c++/53025). */
7407 && cp_noexcept_operand == 0)
7410 tree arg = argarray[num_artificial_parms_for (fn)];
7412 bool trivial = trivial_fn_p (fn);
7414 /* Pull out the real argument, disregarding const-correctness. */
7416 while (CONVERT_EXPR_P (targ)
7417 || TREE_CODE (targ) == NON_LVALUE_EXPR)
7418 targ = TREE_OPERAND (targ, 0);
7419 if (TREE_CODE (targ) == ADDR_EXPR)
7421 targ = TREE_OPERAND (targ, 0);
7422 if (!same_type_ignoring_top_level_qualifiers_p
7423 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
7432 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
7434 /* [class.copy]: the copy constructor is implicitly defined even if
7435 the implementation elided its use. */
7436 if (!trivial || DECL_DELETED_FN (fn))
7439 already_used = true;
7442 /* If we're creating a temp and we already have one, don't create a
7443 new one. If we're not creating a temp but we get one, use
7444 INIT_EXPR to collapse the temp into our target. Otherwise, if the
7445 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
7446 temp or an INIT_EXPR otherwise. */
7448 if (is_dummy_object (fa))
7450 if (TREE_CODE (arg) == TARGET_EXPR)
7453 return force_target_expr (DECL_CONTEXT (fn), arg, complain);
7456 || (TREE_CODE (arg) == TARGET_EXPR
7457 && !unsafe_copy_elision_p (fa, arg)))
7459 tree to = stabilize_reference (cp_build_indirect_ref (fa, RO_NULL,
7462 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
7466 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
7467 && trivial_fn_p (fn)
7468 && !DECL_DELETED_FN (fn))
7470 tree to = stabilize_reference
7471 (cp_build_indirect_ref (argarray[0], RO_NULL, complain));
7472 tree type = TREE_TYPE (to);
7473 tree as_base = CLASSTYPE_AS_BASE (type);
7474 tree arg = argarray[1];
7476 if (is_really_empty_class (type))
7478 /* Avoid copying empty classes. */
7479 val = build2 (COMPOUND_EXPR, void_type_node, to, arg);
7480 TREE_NO_WARNING (val) = 1;
7481 val = build2 (COMPOUND_EXPR, type, val, to);
7482 TREE_NO_WARNING (val) = 1;
7484 else if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
7486 arg = cp_build_indirect_ref (arg, RO_NULL, complain);
7487 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
7491 /* We must only copy the non-tail padding parts. */
7493 tree array_type, alias_set;
7495 arg2 = TYPE_SIZE_UNIT (as_base);
7496 arg0 = cp_build_addr_expr (to, complain);
7498 array_type = build_array_type (char_type_node,
7500 (size_binop (MINUS_EXPR,
7501 arg2, size_int (1))));
7502 alias_set = build_int_cst (build_pointer_type (type), 0);
7503 t = build2 (MODIFY_EXPR, void_type_node,
7504 build2 (MEM_REF, array_type, arg0, alias_set),
7505 build2 (MEM_REF, array_type, arg, alias_set));
7506 val = build2 (COMPOUND_EXPR, TREE_TYPE (to), t, to);
7507 TREE_NO_WARNING (val) = 1;
7512 else if (DECL_DESTRUCTOR_P (fn)
7513 && trivial_fn_p (fn)
7514 && !DECL_DELETED_FN (fn))
7515 return fold_convert (void_type_node, argarray[0]);
7516 /* FIXME handle trivial default constructor, too. */
7518 /* For calls to a multi-versioned function, overload resolution
7519 returns the function with the highest target priority, that is,
7520 the version that will checked for dispatching first. If this
7521 version is inlinable, a direct call to this version can be made
7522 otherwise the call should go through the dispatcher. */
7524 if (DECL_FUNCTION_VERSIONED (fn)
7525 && (current_function_decl == NULL
7526 || !targetm.target_option.can_inline_p (current_function_decl, fn)))
7528 fn = get_function_version_dispatcher (fn);
7532 mark_versions_used (fn);
7536 && !mark_used (fn, complain))
7537 return error_mark_node;
7539 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0
7540 /* Don't mess with virtual lookup in instantiate_non_dependent_expr;
7541 virtual functions can't be constexpr. */
7542 && !in_template_function ())
7545 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
7547 ba_any, NULL, complain);
7548 gcc_assert (binfo && binfo != error_mark_node);
7550 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1,
7552 if (TREE_SIDE_EFFECTS (argarray[0]))
7553 argarray[0] = save_expr (argarray[0]);
7554 t = build_pointer_type (TREE_TYPE (fn));
7555 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
7556 fn = build_java_interface_fn_ref (fn, argarray[0]);
7558 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
7563 fn = build_addr_func (fn, complain);
7564 if (fn == error_mark_node)
7565 return error_mark_node;
7568 tree call = build_cxx_call (fn, nargs, argarray, complain|decltype_flag);
7569 if (TREE_CODE (call) == CALL_EXPR
7570 && (cand->flags & LOOKUP_LIST_INIT_CTOR))
7571 CALL_EXPR_LIST_INIT_P (call) = true;
7575 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
7576 This function performs no overload resolution, conversion, or other
7577 high-level operations. */
7580 build_cxx_call (tree fn, int nargs, tree *argarray,
7581 tsubst_flags_t complain)
7586 /* Remember roughly where this call is. */
7587 location_t loc = EXPR_LOC_OR_LOC (fn, input_location);
7588 fn = build_call_a (fn, nargs, argarray);
7589 SET_EXPR_LOCATION (fn, loc);
7591 fndecl = get_callee_fndecl (fn);
7593 /* Check that arguments to builtin functions match the expectations. */
7595 && DECL_BUILT_IN (fndecl)
7596 && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
7597 && !check_builtin_function_arguments (fndecl, nargs, argarray))
7598 return error_mark_node;
7600 /* If it is a built-in array notation function, then the return type of
7601 the function is the element type of the array passed in as array
7602 notation (i.e. the first parameter of the function). */
7603 if (flag_cilkplus && TREE_CODE (fn) == CALL_EXPR)
7605 enum built_in_function bif =
7606 is_cilkplus_reduce_builtin (CALL_EXPR_FN (fn));
7607 if (bif == BUILT_IN_CILKPLUS_SEC_REDUCE_ADD
7608 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MUL
7609 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MAX
7610 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MIN
7611 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE
7612 || bif == BUILT_IN_CILKPLUS_SEC_REDUCE_MUTATING)
7614 if (call_expr_nargs (fn) == 0)
7616 error_at (EXPR_LOCATION (fn), "Invalid builtin arguments");
7617 return error_mark_node;
7619 /* for bif == BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_ZERO or
7620 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_ZERO or
7621 BUILT_IN_CILKPLUS_SEC_REDUCE_ANY_NONZERO or
7622 BUILT_IN_CILKPLUS_SEC_REDUCE_ALL_NONZERO or
7623 BUILT_IN_CILKPLUS_SEC_REDUCE_MIN_IND or
7624 BUILT_IN_CILKPLUS_SEC_REDUCE_MAX_IND
7625 The pre-defined return-type is the correct one. */
7626 tree array_ntn = CALL_EXPR_ARG (fn, 0);
7627 TREE_TYPE (fn) = TREE_TYPE (array_ntn);
7632 /* Some built-in function calls will be evaluated at compile-time in
7633 fold (). Set optimize to 1 when folding __builtin_constant_p inside
7634 a constexpr function so that fold_builtin_1 doesn't fold it to 0. */
7635 optimize_sav = optimize;
7636 if (!optimize && fndecl && DECL_IS_BUILTIN_CONSTANT_P (fndecl)
7637 && current_function_decl
7638 && DECL_DECLARED_CONSTEXPR_P (current_function_decl))
7640 fn = fold_if_not_in_template (fn);
7641 optimize = optimize_sav;
7643 if (VOID_TYPE_P (TREE_TYPE (fn)))
7646 /* 5.2.2/11: If a function call is a prvalue of object type: if the
7647 function call is either the operand of a decltype-specifier or the
7648 right operand of a comma operator that is the operand of a
7649 decltype-specifier, a temporary object is not introduced for the
7650 prvalue. The type of the prvalue may be incomplete. */
7651 if (!(complain & tf_decltype))
7653 fn = require_complete_type_sfinae (fn, complain);
7654 if (fn == error_mark_node)
7655 return error_mark_node;
7657 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (fn)))
7658 fn = build_cplus_new (TREE_TYPE (fn), fn, complain);
7660 return convert_from_reference (fn);
7663 static GTY(()) tree java_iface_lookup_fn;
7665 /* Make an expression which yields the address of the Java interface
7666 method FN. This is achieved by generating a call to libjava's
7667 _Jv_LookupInterfaceMethodIdx(). */
7670 build_java_interface_fn_ref (tree fn, tree instance)
7672 tree lookup_fn, method, idx;
7673 tree klass_ref, iface, iface_ref;
7676 if (!java_iface_lookup_fn)
7678 tree ftype = build_function_type_list (ptr_type_node,
7679 ptr_type_node, ptr_type_node,
7680 java_int_type_node, NULL_TREE);
7681 java_iface_lookup_fn
7682 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx", ftype,
7683 0, NOT_BUILT_IN, NULL, NULL_TREE);
7686 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
7687 This is the first entry in the vtable. */
7688 klass_ref = build_vtbl_ref (cp_build_indirect_ref (instance, RO_NULL,
7689 tf_warning_or_error),
7692 /* Get the java.lang.Class pointer for the interface being called. */
7693 iface = DECL_CONTEXT (fn);
7694 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
7695 if (!iface_ref || !VAR_P (iface_ref)
7696 || DECL_CONTEXT (iface_ref) != iface)
7698 error ("could not find class$ field in java interface type %qT",
7700 return error_mark_node;
7702 iface_ref = build_address (iface_ref);
7703 iface_ref = convert (build_pointer_type (iface), iface_ref);
7705 /* Determine the itable index of FN. */
7707 for (method = TYPE_METHODS (iface); method; method = DECL_CHAIN (method))
7709 if (!DECL_VIRTUAL_P (method))
7715 idx = build_int_cst (NULL_TREE, i);
7717 lookup_fn = build1 (ADDR_EXPR,
7718 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
7719 java_iface_lookup_fn);
7720 return build_call_nary (ptr_type_node, lookup_fn,
7721 3, klass_ref, iface_ref, idx);
7724 /* Returns the value to use for the in-charge parameter when making a
7725 call to a function with the indicated NAME.
7727 FIXME:Can't we find a neater way to do this mapping? */
7730 in_charge_arg_for_name (tree name)
7732 if (name == base_ctor_identifier
7733 || name == base_dtor_identifier)
7734 return integer_zero_node;
7735 else if (name == complete_ctor_identifier)
7736 return integer_one_node;
7737 else if (name == complete_dtor_identifier)
7738 return integer_two_node;
7739 else if (name == deleting_dtor_identifier)
7740 return integer_three_node;
7742 /* This function should only be called with one of the names listed
7748 /* Build a call to a constructor, destructor, or an assignment
7749 operator for INSTANCE, an expression with class type. NAME
7750 indicates the special member function to call; *ARGS are the
7751 arguments. ARGS may be NULL. This may change ARGS. BINFO
7752 indicates the base of INSTANCE that is to be passed as the `this'
7753 parameter to the member function called.
7755 FLAGS are the LOOKUP_* flags to use when processing the call.
7757 If NAME indicates a complete object constructor, INSTANCE may be
7758 NULL_TREE. In this case, the caller will call build_cplus_new to
7759 store the newly constructed object into a VAR_DECL. */
7762 build_special_member_call (tree instance, tree name, vec<tree, va_gc> **args,
7763 tree binfo, int flags, tsubst_flags_t complain)
7766 /* The type of the subobject to be constructed or destroyed. */
7768 vec<tree, va_gc> *allocated = NULL;
7771 gcc_assert (name == complete_ctor_identifier
7772 || name == base_ctor_identifier
7773 || name == complete_dtor_identifier
7774 || name == base_dtor_identifier
7775 || name == deleting_dtor_identifier
7776 || name == ansi_assopname (NOP_EXPR));
7779 /* Resolve the name. */
7780 if (!complete_type_or_maybe_complain (binfo, NULL_TREE, complain))
7781 return error_mark_node;
7783 binfo = TYPE_BINFO (binfo);
7786 gcc_assert (binfo != NULL_TREE);
7788 class_type = BINFO_TYPE (binfo);
7790 /* Handle the special case where INSTANCE is NULL_TREE. */
7791 if (name == complete_ctor_identifier && !instance)
7792 instance = build_dummy_object (class_type);
7795 if (name == complete_dtor_identifier
7796 || name == base_dtor_identifier
7797 || name == deleting_dtor_identifier)
7798 gcc_assert (args == NULL || vec_safe_is_empty (*args));
7800 /* Convert to the base class, if necessary. */
7801 if (!same_type_ignoring_top_level_qualifiers_p
7802 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
7804 if (name != ansi_assopname (NOP_EXPR))
7805 /* For constructors and destructors, either the base is
7806 non-virtual, or it is virtual but we are doing the
7807 conversion from a constructor or destructor for the
7808 complete object. In either case, we can convert
7810 instance = convert_to_base_statically (instance, binfo);
7812 /* However, for assignment operators, we must convert
7813 dynamically if the base is virtual. */
7814 instance = build_base_path (PLUS_EXPR, instance,
7815 binfo, /*nonnull=*/1, complain);
7819 gcc_assert (instance != NULL_TREE);
7821 fns = lookup_fnfields (binfo, name, 1);
7823 /* When making a call to a constructor or destructor for a subobject
7824 that uses virtual base classes, pass down a pointer to a VTT for
7826 if ((name == base_ctor_identifier
7827 || name == base_dtor_identifier)
7828 && CLASSTYPE_VBASECLASSES (class_type))
7833 /* If the current function is a complete object constructor
7834 or destructor, then we fetch the VTT directly.
7835 Otherwise, we look it up using the VTT we were given. */
7836 vtt = DECL_CHAIN (CLASSTYPE_VTABLES (current_class_type));
7837 vtt = decay_conversion (vtt, complain);
7838 if (vtt == error_mark_node)
7839 return error_mark_node;
7840 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
7841 build2 (EQ_EXPR, boolean_type_node,
7842 current_in_charge_parm, integer_zero_node),
7845 if (BINFO_SUBVTT_INDEX (binfo))
7846 sub_vtt = fold_build_pointer_plus (vtt, BINFO_SUBVTT_INDEX (binfo));
7852 allocated = make_tree_vector ();
7856 vec_safe_insert (*args, 0, sub_vtt);
7859 ret = build_new_method_call (instance, fns, args,
7860 TYPE_BINFO (BINFO_TYPE (binfo)),
7864 if (allocated != NULL)
7865 release_tree_vector (allocated);
7867 if ((complain & tf_error)
7868 && (flags & LOOKUP_DELEGATING_CONS)
7869 && name == complete_ctor_identifier
7870 && TREE_CODE (ret) == CALL_EXPR
7871 && (DECL_ABSTRACT_ORIGIN (TREE_OPERAND (CALL_EXPR_FN (ret), 0))
7872 == current_function_decl))
7873 error ("constructor delegates to itself");
7878 /* Return the NAME, as a C string. The NAME indicates a function that
7879 is a member of TYPE. *FREE_P is set to true if the caller must
7880 free the memory returned.
7882 Rather than go through all of this, we should simply set the names
7883 of constructors and destructors appropriately, and dispense with
7884 ctor_identifier, dtor_identifier, etc. */
7887 name_as_c_string (tree name, tree type, bool *free_p)
7891 /* Assume that we will not allocate memory. */
7893 /* Constructors and destructors are special. */
7894 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
7897 = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (constructor_name (type))));
7898 /* For a destructor, add the '~'. */
7899 if (name == complete_dtor_identifier
7900 || name == base_dtor_identifier
7901 || name == deleting_dtor_identifier)
7903 pretty_name = concat ("~", pretty_name, NULL);
7904 /* Remember that we need to free the memory allocated. */
7908 else if (IDENTIFIER_TYPENAME_P (name))
7910 pretty_name = concat ("operator ",
7911 type_as_string_translate (TREE_TYPE (name),
7912 TFF_PLAIN_IDENTIFIER),
7914 /* Remember that we need to free the memory allocated. */
7918 pretty_name = CONST_CAST (char *, identifier_to_locale (IDENTIFIER_POINTER (name)));
7923 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
7924 be set, upon return, to the function called. ARGS may be NULL.
7925 This may change ARGS. */
7928 build_new_method_call_1 (tree instance, tree fns, vec<tree, va_gc> **args,
7929 tree conversion_path, int flags,
7930 tree *fn_p, tsubst_flags_t complain)
7932 struct z_candidate *candidates = 0, *cand;
7933 tree explicit_targs = NULL_TREE;
7934 tree basetype = NULL_TREE;
7935 tree access_binfo, binfo;
7937 tree first_mem_arg = NULL_TREE;
7939 bool skip_first_for_error;
7940 vec<tree, va_gc> *user_args;
7943 int template_only = 0;
7947 vec<tree, va_gc> *orig_args = NULL;
7950 gcc_assert (instance != NULL_TREE);
7952 /* We don't know what function we're going to call, yet. */
7956 if (error_operand_p (instance)
7957 || !fns || error_operand_p (fns))
7958 return error_mark_node;
7960 if (!BASELINK_P (fns))
7962 if (complain & tf_error)
7963 error ("call to non-function %qD", fns);
7964 return error_mark_node;
7967 orig_instance = instance;
7970 /* Dismantle the baselink to collect all the information we need. */
7971 if (!conversion_path)
7972 conversion_path = BASELINK_BINFO (fns);
7973 access_binfo = BASELINK_ACCESS_BINFO (fns);
7974 binfo = BASELINK_BINFO (fns);
7975 optype = BASELINK_OPTYPE (fns);
7976 fns = BASELINK_FUNCTIONS (fns);
7977 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7979 explicit_targs = TREE_OPERAND (fns, 1);
7980 fns = TREE_OPERAND (fns, 0);
7983 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
7984 || TREE_CODE (fns) == TEMPLATE_DECL
7985 || TREE_CODE (fns) == OVERLOAD);
7986 fn = get_first_fn (fns);
7987 name = DECL_NAME (fn);
7989 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
7990 gcc_assert (CLASS_TYPE_P (basetype));
7992 if (processing_template_decl)
7994 orig_args = args == NULL ? NULL : make_tree_vector_copy (*args);
7995 instance = build_non_dependent_expr (instance);
7997 make_args_non_dependent (*args);
8000 user_args = args == NULL ? NULL : *args;
8001 /* Under DR 147 A::A() is an invalid constructor call,
8002 not a functional cast. */
8003 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn))
8005 if (! (complain & tf_error))
8006 return error_mark_node;
8008 if (permerror (input_location,
8009 "cannot call constructor %<%T::%D%> directly",
8011 inform (input_location, "for a function-style cast, remove the "
8012 "redundant %<::%D%>", name);
8013 call = build_functional_cast (basetype, build_tree_list_vec (user_args),
8018 /* Figure out whether to skip the first argument for the error
8019 message we will display to users if an error occurs. We don't
8020 want to display any compiler-generated arguments. The "this"
8021 pointer hasn't been added yet. However, we must remove the VTT
8022 pointer if this is a call to a base-class constructor or
8024 skip_first_for_error = false;
8025 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
8027 /* Callers should explicitly indicate whether they want to construct
8028 the complete object or just the part without virtual bases. */
8029 gcc_assert (name != ctor_identifier);
8030 /* Similarly for destructors. */
8031 gcc_assert (name != dtor_identifier);
8032 /* Remove the VTT pointer, if present. */
8033 if ((name == base_ctor_identifier || name == base_dtor_identifier)
8034 && CLASSTYPE_VBASECLASSES (basetype))
8035 skip_first_for_error = true;
8038 /* Process the argument list. */
8039 if (args != NULL && *args != NULL)
8041 *args = resolve_args (*args, complain);
8043 return error_mark_node;
8046 /* Consider the object argument to be used even if we end up selecting a
8047 static member function. */
8048 instance = mark_type_use (instance);
8050 /* It's OK to call destructors and constructors on cv-qualified objects.
8051 Therefore, convert the INSTANCE to the unqualified type, if
8053 if (DECL_DESTRUCTOR_P (fn)
8054 || DECL_CONSTRUCTOR_P (fn))
8056 if (!same_type_p (basetype, TREE_TYPE (instance)))
8058 instance = build_this (instance);
8059 instance = build_nop (build_pointer_type (basetype), instance);
8060 instance = build_fold_indirect_ref (instance);
8063 if (DECL_DESTRUCTOR_P (fn))
8064 name = complete_dtor_identifier;
8066 /* For the overload resolution we need to find the actual `this`
8067 that would be captured if the call turns out to be to a
8068 non-static member function. Do not actually capture it at this
8070 if (DECL_CONSTRUCTOR_P (fn))
8071 /* Constructors don't use the enclosing 'this'. */
8072 first_mem_arg = instance;
8074 first_mem_arg = maybe_resolve_dummy (instance, false);
8076 /* Get the high-water mark for the CONVERSION_OBSTACK. */
8077 p = conversion_obstack_alloc (0);
8079 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
8080 initializer, not T({ }). */
8081 if (DECL_CONSTRUCTOR_P (fn) && args != NULL && !vec_safe_is_empty (*args)
8082 && DIRECT_LIST_INIT_P ((**args)[0]))
8084 tree init_list = (**args)[0];
8085 tree init = NULL_TREE;
8087 gcc_assert ((*args)->length () == 1
8088 && !(flags & LOOKUP_ONLYCONVERTING));
8090 /* If the initializer list has no elements and T is a class type with
8091 a default constructor, the object is value-initialized. Handle
8092 this here so we don't need to handle it wherever we use
8093 build_special_member_call. */
8094 if (CONSTRUCTOR_NELTS (init_list) == 0
8095 && TYPE_HAS_DEFAULT_CONSTRUCTOR (basetype)
8096 /* For a user-provided default constructor, use the normal
8097 mechanisms so that protected access works. */
8098 && type_has_non_user_provided_default_constructor (basetype)
8099 && !processing_template_decl)
8100 init = build_value_init (basetype, complain);
8102 /* If BASETYPE is an aggregate, we need to do aggregate
8104 else if (CP_AGGREGATE_TYPE_P (basetype))
8105 init = digest_init (basetype, init_list, complain);
8109 if (is_dummy_object (instance))
8110 return get_target_expr_sfinae (init, complain);
8111 init = build2 (INIT_EXPR, TREE_TYPE (instance), instance, init);
8112 TREE_SIDE_EFFECTS (init) = true;
8116 /* Otherwise go ahead with overload resolution. */
8117 add_list_candidates (fns, first_mem_arg, init_list,
8118 basetype, explicit_targs, template_only,
8119 conversion_path, access_binfo, flags,
8120 &candidates, complain);
8124 add_candidates (fns, first_mem_arg, user_args, optype,
8125 explicit_targs, template_only, conversion_path,
8126 access_binfo, flags, &candidates, complain);
8128 any_viable_p = false;
8129 candidates = splice_viable (candidates, false, &any_viable_p);
8133 if (complain & tf_error)
8135 if (!COMPLETE_OR_OPEN_TYPE_P (basetype))
8136 cxx_incomplete_type_error (instance, basetype);
8138 error ("no matching function for call to %<%T::operator %T(%A)%#V%>",
8139 basetype, optype, build_tree_list_vec (user_args),
8140 TREE_TYPE (instance));
8147 pretty_name = name_as_c_string (name, basetype, &free_p);
8148 arglist = build_tree_list_vec (user_args);
8149 if (skip_first_for_error)
8150 arglist = TREE_CHAIN (arglist);
8151 error ("no matching function for call to %<%T::%s(%A)%#V%>",
8152 basetype, pretty_name, arglist,
8153 TREE_TYPE (instance));
8157 print_z_candidates (location_of (name), candidates);
8159 call = error_mark_node;
8163 cand = tourney (candidates, complain);
8170 if (complain & tf_error)
8172 pretty_name = name_as_c_string (name, basetype, &free_p);
8173 arglist = build_tree_list_vec (user_args);
8174 if (skip_first_for_error)
8175 arglist = TREE_CHAIN (arglist);
8176 if (!any_strictly_viable (candidates))
8177 error ("no matching function for call to %<%s(%A)%>",
8178 pretty_name, arglist);
8180 error ("call of overloaded %<%s(%A)%> is ambiguous",
8181 pretty_name, arglist);
8182 print_z_candidates (location_of (name), candidates);
8186 call = error_mark_node;
8193 if (!(flags & LOOKUP_NONVIRTUAL)
8194 && DECL_PURE_VIRTUAL_P (fn)
8195 && instance == current_class_ref
8196 && (complain & tf_warning))
8198 /* This is not an error, it is runtime undefined
8200 if (!current_function_decl)
8201 warning (0, "pure virtual %q#D called from "
8202 "non-static data member initializer", fn);
8203 else if (DECL_CONSTRUCTOR_P (current_function_decl)
8204 || DECL_DESTRUCTOR_P (current_function_decl))
8205 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl)
8206 ? "pure virtual %q#D called from constructor"
8207 : "pure virtual %q#D called from destructor"),
8211 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
8212 && !DECL_CONSTRUCTOR_P (fn)
8213 && is_dummy_object (instance))
8215 instance = maybe_resolve_dummy (instance, true);
8216 if (instance == error_mark_node)
8217 call = error_mark_node;
8218 else if (!is_dummy_object (instance))
8220 /* We captured 'this' in the current lambda now that
8221 we know we really need it. */
8222 cand->first_arg = instance;
8226 if (complain & tf_error)
8227 error ("cannot call member function %qD without object",
8229 call = error_mark_node;
8233 if (call != error_mark_node)
8235 /* Optimize away vtable lookup if we know that this
8236 function can't be overridden. We need to check if
8237 the context and the type where we found fn are the same,
8238 actually FN might be defined in a different class
8239 type because of a using-declaration. In this case, we
8240 do not want to perform a non-virtual call. */
8241 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
8242 && same_type_ignoring_top_level_qualifiers_p
8243 (DECL_CONTEXT (fn), BINFO_TYPE (binfo))
8244 && resolves_to_fixed_type_p (instance, 0))
8245 flags |= LOOKUP_NONVIRTUAL;
8247 flags |= LOOKUP_EXPLICIT_TMPL_ARGS;
8248 /* Now we know what function is being called. */
8251 /* Build the actual CALL_EXPR. */
8252 call = build_over_call (cand, flags, complain);
8253 /* In an expression of the form `a->f()' where `f' turns
8254 out to be a static member function, `a' is
8255 none-the-less evaluated. */
8256 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
8257 && !is_dummy_object (instance)
8258 && TREE_SIDE_EFFECTS (instance))
8259 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
8261 else if (call != error_mark_node
8262 && DECL_DESTRUCTOR_P (cand->fn)
8263 && !VOID_TYPE_P (TREE_TYPE (call)))
8264 /* An explicit call of the form "x->~X()" has type
8265 "void". However, on platforms where destructors
8266 return "this" (i.e., those where
8267 targetm.cxx.cdtor_returns_this is true), such calls
8268 will appear to have a return value of pointer type
8269 to the low-level call machinery. We do not want to
8270 change the low-level machinery, since we want to be
8271 able to optimize "delete f()" on such platforms as
8272 "operator delete(~X(f()))" (rather than generating
8273 "t = f(), ~X(t), operator delete (t)"). */
8274 call = build_nop (void_type_node, call);
8279 if (processing_template_decl && call != error_mark_node)
8281 bool cast_to_void = false;
8283 if (TREE_CODE (call) == COMPOUND_EXPR)
8284 call = TREE_OPERAND (call, 1);
8285 else if (TREE_CODE (call) == NOP_EXPR)
8287 cast_to_void = true;
8288 call = TREE_OPERAND (call, 0);
8290 if (INDIRECT_REF_P (call))
8291 call = TREE_OPERAND (call, 0);
8292 call = (build_min_non_dep_call_vec
8294 build_min (COMPONENT_REF, TREE_TYPE (CALL_EXPR_FN (call)),
8295 orig_instance, orig_fns, NULL_TREE),
8297 SET_EXPR_LOCATION (call, input_location);
8298 call = convert_from_reference (call);
8300 call = build_nop (void_type_node, call);
8303 /* Free all the conversions we allocated. */
8304 obstack_free (&conversion_obstack, p);
8306 if (orig_args != NULL)
8307 release_tree_vector (orig_args);
8312 /* Wrapper for above. */
8315 build_new_method_call (tree instance, tree fns, vec<tree, va_gc> **args,
8316 tree conversion_path, int flags,
8317 tree *fn_p, tsubst_flags_t complain)
8320 bool subtime = timevar_cond_start (TV_OVERLOAD);
8321 ret = build_new_method_call_1 (instance, fns, args, conversion_path, flags,
8323 timevar_cond_stop (TV_OVERLOAD, subtime);
8327 /* Returns true iff standard conversion sequence ICS1 is a proper
8328 subsequence of ICS2. */
8331 is_subseq (conversion *ics1, conversion *ics2)
8333 /* We can assume that a conversion of the same code
8334 between the same types indicates a subsequence since we only get
8335 here if the types we are converting from are the same. */
8337 while (ics1->kind == ck_rvalue
8338 || ics1->kind == ck_lvalue)
8339 ics1 = next_conversion (ics1);
8343 while (ics2->kind == ck_rvalue
8344 || ics2->kind == ck_lvalue)
8345 ics2 = next_conversion (ics2);
8347 if (ics2->kind == ck_user
8348 || ics2->kind == ck_ambig
8349 || ics2->kind == ck_aggr
8350 || ics2->kind == ck_list
8351 || ics2->kind == ck_identity)
8352 /* At this point, ICS1 cannot be a proper subsequence of
8353 ICS2. We can get a USER_CONV when we are comparing the
8354 second standard conversion sequence of two user conversion
8358 ics2 = next_conversion (ics2);
8360 if (ics2->kind == ics1->kind
8361 && same_type_p (ics2->type, ics1->type)
8362 && same_type_p (next_conversion (ics2)->type,
8363 next_conversion (ics1)->type))
8368 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
8369 be any _TYPE nodes. */
8372 is_properly_derived_from (tree derived, tree base)
8374 if (!CLASS_TYPE_P (derived) || !CLASS_TYPE_P (base))
8377 /* We only allow proper derivation here. The DERIVED_FROM_P macro
8378 considers every class derived from itself. */
8379 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
8380 && DERIVED_FROM_P (base, derived));
8383 /* We build the ICS for an implicit object parameter as a pointer
8384 conversion sequence. However, such a sequence should be compared
8385 as if it were a reference conversion sequence. If ICS is the
8386 implicit conversion sequence for an implicit object parameter,
8387 modify it accordingly. */
8390 maybe_handle_implicit_object (conversion **ics)
8394 /* [over.match.funcs]
8396 For non-static member functions, the type of the
8397 implicit object parameter is "reference to cv X"
8398 where X is the class of which the function is a
8399 member and cv is the cv-qualification on the member
8400 function declaration. */
8401 conversion *t = *ics;
8402 tree reference_type;
8404 /* The `this' parameter is a pointer to a class type. Make the
8405 implicit conversion talk about a reference to that same class
8407 reference_type = TREE_TYPE (t->type);
8408 reference_type = build_reference_type (reference_type);
8410 if (t->kind == ck_qual)
8411 t = next_conversion (t);
8412 if (t->kind == ck_ptr)
8413 t = next_conversion (t);
8414 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
8415 t = direct_reference_binding (reference_type, t);
8417 t->rvaluedness_matches_p = 0;
8422 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
8423 and return the initial reference binding conversion. Otherwise,
8424 leave *ICS unchanged and return NULL. */
8427 maybe_handle_ref_bind (conversion **ics)
8429 if ((*ics)->kind == ck_ref_bind)
8431 conversion *old_ics = *ics;
8432 *ics = next_conversion (old_ics);
8433 (*ics)->user_conv_p = old_ics->user_conv_p;
8440 /* Compare two implicit conversion sequences according to the rules set out in
8441 [over.ics.rank]. Return values:
8443 1: ics1 is better than ics2
8444 -1: ics2 is better than ics1
8445 0: ics1 and ics2 are indistinguishable */
8448 compare_ics (conversion *ics1, conversion *ics2)
8454 tree deref_from_type1 = NULL_TREE;
8455 tree deref_from_type2 = NULL_TREE;
8456 tree deref_to_type1 = NULL_TREE;
8457 tree deref_to_type2 = NULL_TREE;
8458 conversion_rank rank1, rank2;
8460 /* REF_BINDING is nonzero if the result of the conversion sequence
8461 is a reference type. In that case REF_CONV is the reference
8462 binding conversion. */
8463 conversion *ref_conv1;
8464 conversion *ref_conv2;
8466 /* Compare badness before stripping the reference conversion. */
8467 if (ics1->bad_p > ics2->bad_p)
8469 else if (ics1->bad_p < ics2->bad_p)
8472 /* Handle implicit object parameters. */
8473 maybe_handle_implicit_object (&ics1);
8474 maybe_handle_implicit_object (&ics2);
8476 /* Handle reference parameters. */
8477 ref_conv1 = maybe_handle_ref_bind (&ics1);
8478 ref_conv2 = maybe_handle_ref_bind (&ics2);
8480 /* List-initialization sequence L1 is a better conversion sequence than
8481 list-initialization sequence L2 if L1 converts to
8482 std::initializer_list<X> for some X and L2 does not. */
8483 if (ics1->kind == ck_list && ics2->kind != ck_list)
8485 if (ics2->kind == ck_list && ics1->kind != ck_list)
8490 When comparing the basic forms of implicit conversion sequences (as
8491 defined in _over.best.ics_)
8493 --a standard conversion sequence (_over.ics.scs_) is a better
8494 conversion sequence than a user-defined conversion sequence
8495 or an ellipsis conversion sequence, and
8497 --a user-defined conversion sequence (_over.ics.user_) is a
8498 better conversion sequence than an ellipsis conversion sequence
8499 (_over.ics.ellipsis_). */
8500 /* Use BAD_CONVERSION_RANK because we already checked for a badness
8501 mismatch. If both ICS are bad, we try to make a decision based on
8502 what would have happened if they'd been good. This is not an
8503 extension, we'll still give an error when we build up the call; this
8504 just helps us give a more helpful error message. */
8505 rank1 = BAD_CONVERSION_RANK (ics1);
8506 rank2 = BAD_CONVERSION_RANK (ics2);
8510 else if (rank1 < rank2)
8513 if (ics1->ellipsis_p)
8514 /* Both conversions are ellipsis conversions. */
8517 /* User-defined conversion sequence U1 is a better conversion sequence
8518 than another user-defined conversion sequence U2 if they contain the
8519 same user-defined conversion operator or constructor and if the sec-
8520 ond standard conversion sequence of U1 is better than the second
8521 standard conversion sequence of U2. */
8523 /* Handle list-conversion with the same code even though it isn't always
8524 ranked as a user-defined conversion and it doesn't have a second
8525 standard conversion sequence; it will still have the desired effect.
8526 Specifically, we need to do the reference binding comparison at the
8527 end of this function. */
8529 if (ics1->user_conv_p || ics1->kind == ck_list || ics1->kind == ck_aggr)
8534 for (t1 = ics1; t1->kind != ck_user; t1 = next_conversion (t1))
8535 if (t1->kind == ck_ambig || t1->kind == ck_aggr
8536 || t1->kind == ck_list)
8538 for (t2 = ics2; t2->kind != ck_user; t2 = next_conversion (t2))
8539 if (t2->kind == ck_ambig || t2->kind == ck_aggr
8540 || t2->kind == ck_list)
8543 if (t1->kind != t2->kind)
8545 else if (t1->kind == ck_user)
8547 if (t1->cand->fn != t2->cand->fn)
8552 /* For ambiguous or aggregate conversions, use the target type as
8553 a proxy for the conversion function. */
8554 if (!same_type_ignoring_top_level_qualifiers_p (t1->type, t2->type))
8558 /* We can just fall through here, after setting up
8559 FROM_TYPE1 and FROM_TYPE2. */
8560 from_type1 = t1->type;
8561 from_type2 = t2->type;
8568 /* We're dealing with two standard conversion sequences.
8572 Standard conversion sequence S1 is a better conversion
8573 sequence than standard conversion sequence S2 if
8575 --S1 is a proper subsequence of S2 (comparing the conversion
8576 sequences in the canonical form defined by _over.ics.scs_,
8577 excluding any Lvalue Transformation; the identity
8578 conversion sequence is considered to be a subsequence of
8579 any non-identity conversion sequence */
8582 while (t1->kind != ck_identity)
8583 t1 = next_conversion (t1);
8584 from_type1 = t1->type;
8587 while (t2->kind != ck_identity)
8588 t2 = next_conversion (t2);
8589 from_type2 = t2->type;
8592 /* One sequence can only be a subsequence of the other if they start with
8593 the same type. They can start with different types when comparing the
8594 second standard conversion sequence in two user-defined conversion
8596 if (same_type_p (from_type1, from_type2))
8598 if (is_subseq (ics1, ics2))
8600 if (is_subseq (ics2, ics1))
8608 --the rank of S1 is better than the rank of S2 (by the rules
8611 Standard conversion sequences are ordered by their ranks: an Exact
8612 Match is a better conversion than a Promotion, which is a better
8613 conversion than a Conversion.
8615 Two conversion sequences with the same rank are indistinguishable
8616 unless one of the following rules applies:
8618 --A conversion that does not a convert a pointer, pointer to member,
8619 or std::nullptr_t to bool is better than one that does.
8621 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
8622 so that we do not have to check it explicitly. */
8623 if (ics1->rank < ics2->rank)
8625 else if (ics2->rank < ics1->rank)
8628 to_type1 = ics1->type;
8629 to_type2 = ics2->type;
8631 /* A conversion from scalar arithmetic type to complex is worse than a
8632 conversion between scalar arithmetic types. */
8633 if (same_type_p (from_type1, from_type2)
8634 && ARITHMETIC_TYPE_P (from_type1)
8635 && ARITHMETIC_TYPE_P (to_type1)
8636 && ARITHMETIC_TYPE_P (to_type2)
8637 && ((TREE_CODE (to_type1) == COMPLEX_TYPE)
8638 != (TREE_CODE (to_type2) == COMPLEX_TYPE)))
8640 if (TREE_CODE (to_type1) == COMPLEX_TYPE)
8646 if (TYPE_PTR_P (from_type1)
8647 && TYPE_PTR_P (from_type2)
8648 && TYPE_PTR_P (to_type1)
8649 && TYPE_PTR_P (to_type2))
8651 deref_from_type1 = TREE_TYPE (from_type1);
8652 deref_from_type2 = TREE_TYPE (from_type2);
8653 deref_to_type1 = TREE_TYPE (to_type1);
8654 deref_to_type2 = TREE_TYPE (to_type2);
8656 /* The rules for pointers to members A::* are just like the rules
8657 for pointers A*, except opposite: if B is derived from A then
8658 A::* converts to B::*, not vice versa. For that reason, we
8659 switch the from_ and to_ variables here. */
8660 else if ((TYPE_PTRDATAMEM_P (from_type1) && TYPE_PTRDATAMEM_P (from_type2)
8661 && TYPE_PTRDATAMEM_P (to_type1) && TYPE_PTRDATAMEM_P (to_type2))
8662 || (TYPE_PTRMEMFUNC_P (from_type1)
8663 && TYPE_PTRMEMFUNC_P (from_type2)
8664 && TYPE_PTRMEMFUNC_P (to_type1)
8665 && TYPE_PTRMEMFUNC_P (to_type2)))
8667 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
8668 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
8669 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
8670 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
8673 if (deref_from_type1 != NULL_TREE
8674 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type1))
8675 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_from_type2)))
8677 /* This was one of the pointer or pointer-like conversions.
8681 --If class B is derived directly or indirectly from class A,
8682 conversion of B* to A* is better than conversion of B* to
8683 void*, and conversion of A* to void* is better than
8684 conversion of B* to void*. */
8685 if (VOID_TYPE_P (deref_to_type1)
8686 && VOID_TYPE_P (deref_to_type2))
8688 if (is_properly_derived_from (deref_from_type1,
8691 else if (is_properly_derived_from (deref_from_type2,
8695 else if (VOID_TYPE_P (deref_to_type1)
8696 || VOID_TYPE_P (deref_to_type2))
8698 if (same_type_p (deref_from_type1, deref_from_type2))
8700 if (VOID_TYPE_P (deref_to_type2))
8702 if (is_properly_derived_from (deref_from_type1,
8706 /* We know that DEREF_TO_TYPE1 is `void' here. */
8707 else if (is_properly_derived_from (deref_from_type1,
8712 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type1))
8713 && RECORD_OR_UNION_CODE_P (TREE_CODE (deref_to_type2)))
8717 --If class B is derived directly or indirectly from class A
8718 and class C is derived directly or indirectly from B,
8720 --conversion of C* to B* is better than conversion of C* to
8723 --conversion of B* to A* is better than conversion of C* to
8725 if (same_type_p (deref_from_type1, deref_from_type2))
8727 if (is_properly_derived_from (deref_to_type1,
8730 else if (is_properly_derived_from (deref_to_type2,
8734 else if (same_type_p (deref_to_type1, deref_to_type2))
8736 if (is_properly_derived_from (deref_from_type2,
8739 else if (is_properly_derived_from (deref_from_type1,
8745 else if (CLASS_TYPE_P (non_reference (from_type1))
8746 && same_type_p (from_type1, from_type2))
8748 tree from = non_reference (from_type1);
8752 --binding of an expression of type C to a reference of type
8753 B& is better than binding an expression of type C to a
8754 reference of type A&
8756 --conversion of C to B is better than conversion of C to A, */
8757 if (is_properly_derived_from (from, to_type1)
8758 && is_properly_derived_from (from, to_type2))
8760 if (is_properly_derived_from (to_type1, to_type2))
8762 else if (is_properly_derived_from (to_type2, to_type1))
8766 else if (CLASS_TYPE_P (non_reference (to_type1))
8767 && same_type_p (to_type1, to_type2))
8769 tree to = non_reference (to_type1);
8773 --binding of an expression of type B to a reference of type
8774 A& is better than binding an expression of type C to a
8775 reference of type A&,
8777 --conversion of B to A is better than conversion of C to A */
8778 if (is_properly_derived_from (from_type1, to)
8779 && is_properly_derived_from (from_type2, to))
8781 if (is_properly_derived_from (from_type2, from_type1))
8783 else if (is_properly_derived_from (from_type1, from_type2))
8790 --S1 and S2 differ only in their qualification conversion and yield
8791 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
8792 qualification signature of type T1 is a proper subset of the cv-
8793 qualification signature of type T2 */
8794 if (ics1->kind == ck_qual
8795 && ics2->kind == ck_qual
8796 && same_type_p (from_type1, from_type2))
8798 int result = comp_cv_qual_signature (to_type1, to_type2);
8805 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
8806 to an implicit object parameter of a non-static member function
8807 declared without a ref-qualifier, and either S1 binds an lvalue
8808 reference to an lvalue and S2 binds an rvalue reference or S1 binds an
8809 rvalue reference to an rvalue and S2 binds an lvalue reference (C++0x
8810 draft standard, 13.3.3.2)
8812 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
8813 types to which the references refer are the same type except for
8814 top-level cv-qualifiers, and the type to which the reference
8815 initialized by S2 refers is more cv-qualified than the type to
8816 which the reference initialized by S1 refers.
8818 DR 1328 [over.match.best]: the context is an initialization by
8819 conversion function for direct reference binding (13.3.1.6) of a
8820 reference to function type, the return type of F1 is the same kind of
8821 reference (i.e. lvalue or rvalue) as the reference being initialized,
8822 and the return type of F2 is not. */
8824 if (ref_conv1 && ref_conv2)
8826 if (!ref_conv1->this_p && !ref_conv2->this_p
8827 && (ref_conv1->rvaluedness_matches_p
8828 != ref_conv2->rvaluedness_matches_p)
8829 && (same_type_p (ref_conv1->type, ref_conv2->type)
8830 || (TYPE_REF_IS_RVALUE (ref_conv1->type)
8831 != TYPE_REF_IS_RVALUE (ref_conv2->type))))
8833 if (ref_conv1->bad_p
8834 && !same_type_p (TREE_TYPE (ref_conv1->type),
8835 TREE_TYPE (ref_conv2->type)))
8836 /* Don't prefer a bad conversion that drops cv-quals to a bad
8837 conversion with the wrong rvalueness. */
8839 return (ref_conv1->rvaluedness_matches_p
8840 - ref_conv2->rvaluedness_matches_p);
8843 if (same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
8845 int q1 = cp_type_quals (TREE_TYPE (ref_conv1->type));
8846 int q2 = cp_type_quals (TREE_TYPE (ref_conv2->type));
8847 if (ref_conv1->bad_p)
8849 /* Prefer the one that drops fewer cv-quals. */
8850 tree ftype = next_conversion (ref_conv1)->type;
8851 int fquals = cp_type_quals (ftype);
8855 return comp_cv_qualification (q2, q1);
8859 /* Neither conversion sequence is better than the other. */
8863 /* The source type for this standard conversion sequence. */
8866 source_type (conversion *t)
8868 for (;; t = next_conversion (t))
8870 if (t->kind == ck_user
8871 || t->kind == ck_ambig
8872 || t->kind == ck_identity)
8878 /* Note a warning about preferring WINNER to LOSER. We do this by storing
8879 a pointer to LOSER and re-running joust to produce the warning if WINNER
8880 is actually used. */
8883 add_warning (struct z_candidate *winner, struct z_candidate *loser)
8885 candidate_warning *cw = (candidate_warning *)
8886 conversion_obstack_alloc (sizeof (candidate_warning));
8888 cw->next = winner->warnings;
8889 winner->warnings = cw;
8892 /* Compare two candidates for overloading as described in
8893 [over.match.best]. Return values:
8895 1: cand1 is better than cand2
8896 -1: cand2 is better than cand1
8897 0: cand1 and cand2 are indistinguishable */
8900 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn,
8901 tsubst_flags_t complain)
8904 int off1 = 0, off2 = 0;
8908 /* Candidates that involve bad conversions are always worse than those
8910 if (cand1->viable > cand2->viable)
8912 if (cand1->viable < cand2->viable)
8915 /* If we have two pseudo-candidates for conversions to the same type,
8916 or two candidates for the same function, arbitrarily pick one. */
8917 if (cand1->fn == cand2->fn
8918 && (IS_TYPE_OR_DECL_P (cand1->fn)))
8921 /* Prefer a non-deleted function over an implicitly deleted move
8922 constructor or assignment operator. This differs slightly from the
8923 wording for issue 1402 (which says the move op is ignored by overload
8924 resolution), but this way produces better error messages. */
8925 if (TREE_CODE (cand1->fn) == FUNCTION_DECL
8926 && TREE_CODE (cand2->fn) == FUNCTION_DECL
8927 && DECL_DELETED_FN (cand1->fn) != DECL_DELETED_FN (cand2->fn))
8929 if (DECL_DELETED_FN (cand1->fn) && DECL_DEFAULTED_FN (cand1->fn)
8930 && move_fn_p (cand1->fn))
8932 if (DECL_DELETED_FN (cand2->fn) && DECL_DEFAULTED_FN (cand2->fn)
8933 && move_fn_p (cand2->fn))
8937 /* a viable function F1
8938 is defined to be a better function than another viable function F2 if
8939 for all arguments i, ICSi(F1) is not a worse conversion sequence than
8940 ICSi(F2), and then */
8942 /* for some argument j, ICSj(F1) is a better conversion sequence than
8945 /* For comparing static and non-static member functions, we ignore
8946 the implicit object parameter of the non-static function. The
8947 standard says to pretend that the static function has an object
8948 parm, but that won't work with operator overloading. */
8949 len = cand1->num_convs;
8950 if (len != cand2->num_convs)
8952 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
8953 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
8955 if (DECL_CONSTRUCTOR_P (cand1->fn)
8956 && is_list_ctor (cand1->fn) != is_list_ctor (cand2->fn))
8957 /* We're comparing a near-match list constructor and a near-match
8958 non-list constructor. Just treat them as unordered. */
8961 gcc_assert (static_1 != static_2);
8972 for (i = 0; i < len; ++i)
8974 conversion *t1 = cand1->convs[i + off1];
8975 conversion *t2 = cand2->convs[i + off2];
8976 int comp = compare_ics (t1, t2);
8980 if ((complain & tf_warning)
8982 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
8983 == cr_std + cr_promotion)
8984 && t1->kind == ck_std
8985 && t2->kind == ck_std
8986 && TREE_CODE (t1->type) == INTEGER_TYPE
8987 && TREE_CODE (t2->type) == INTEGER_TYPE
8988 && (TYPE_PRECISION (t1->type)
8989 == TYPE_PRECISION (t2->type))
8990 && (TYPE_UNSIGNED (next_conversion (t1)->type)
8991 || (TREE_CODE (next_conversion (t1)->type)
8994 tree type = next_conversion (t1)->type;
8996 struct z_candidate *w, *l;
8998 type1 = t1->type, type2 = t2->type,
8999 w = cand1, l = cand2;
9001 type1 = t2->type, type2 = t1->type,
9002 w = cand2, l = cand1;
9006 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
9007 type, type1, type2);
9008 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
9014 if (winner && comp != winner)
9023 /* warn about confusing overload resolution for user-defined conversions,
9024 either between a constructor and a conversion op, or between two
9026 if ((complain & tf_warning)
9027 && winner && warn_conversion && cand1->second_conv
9028 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
9029 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
9031 struct z_candidate *w, *l;
9032 bool give_warning = false;
9035 w = cand1, l = cand2;
9037 w = cand2, l = cand1;
9039 /* We don't want to complain about `X::operator T1 ()'
9040 beating `X::operator T2 () const', when T2 is a no less
9041 cv-qualified version of T1. */
9042 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
9043 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
9045 tree t = TREE_TYPE (TREE_TYPE (l->fn));
9046 tree f = TREE_TYPE (TREE_TYPE (w->fn));
9048 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
9053 if (!comp_ptr_ttypes (t, f))
9054 give_warning = true;
9057 give_warning = true;
9063 tree source = source_type (w->convs[0]);
9064 if (! DECL_CONSTRUCTOR_P (w->fn))
9065 source = TREE_TYPE (source);
9066 if (warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn)
9067 && warning (OPT_Wconversion, " for conversion from %qT to %qT",
9068 source, w->second_conv->type))
9070 inform (input_location, " because conversion sequence for the argument is better");
9080 /* DR 495 moved this tiebreaker above the template ones. */
9082 the context is an initialization by user-defined conversion (see
9083 _dcl.init_ and _over.match.user_) and the standard conversion
9084 sequence from the return type of F1 to the destination type (i.e.,
9085 the type of the entity being initialized) is a better conversion
9086 sequence than the standard conversion sequence from the return type
9087 of F2 to the destination type. */
9089 if (cand1->second_conv)
9091 winner = compare_ics (cand1->second_conv, cand2->second_conv);
9097 F1 is a non-template function and F2 is a template function
9100 if (!cand1->template_decl && cand2->template_decl)
9102 else if (cand1->template_decl && !cand2->template_decl)
9106 F1 and F2 are template functions and the function template for F1 is
9107 more specialized than the template for F2 according to the partial
9110 if (cand1->template_decl && cand2->template_decl)
9112 winner = more_specialized_fn
9113 (TI_TEMPLATE (cand1->template_decl),
9114 TI_TEMPLATE (cand2->template_decl),
9115 /* [temp.func.order]: The presence of unused ellipsis and default
9116 arguments has no effect on the partial ordering of function
9117 templates. add_function_candidate() will not have
9118 counted the "this" argument for constructors. */
9119 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
9124 /* Check whether we can discard a builtin candidate, either because we
9125 have two identical ones or matching builtin and non-builtin candidates.
9127 (Pedantically in the latter case the builtin which matched the user
9128 function should not be added to the overload set, but we spot it here.
9131 ... the builtin candidates include ...
9132 - do not have the same parameter type list as any non-template
9133 non-member candidate. */
9135 if (identifier_p (cand1->fn) || identifier_p (cand2->fn))
9137 for (i = 0; i < len; ++i)
9138 if (!same_type_p (cand1->convs[i]->type,
9139 cand2->convs[i]->type))
9141 if (i == cand1->num_convs)
9143 if (cand1->fn == cand2->fn)
9144 /* Two built-in candidates; arbitrarily pick one. */
9146 else if (identifier_p (cand1->fn))
9147 /* cand1 is built-in; prefer cand2. */
9150 /* cand2 is built-in; prefer cand1. */
9155 /* For candidates of a multi-versioned function, make the version with
9156 the highest priority win. This version will be checked for dispatching
9157 first. If this version can be inlined into the caller, the front-end
9158 will simply make a direct call to this function. */
9160 if (TREE_CODE (cand1->fn) == FUNCTION_DECL
9161 && DECL_FUNCTION_VERSIONED (cand1->fn)
9162 && TREE_CODE (cand2->fn) == FUNCTION_DECL
9163 && DECL_FUNCTION_VERSIONED (cand2->fn))
9165 tree f1 = TREE_TYPE (cand1->fn);
9166 tree f2 = TREE_TYPE (cand2->fn);
9167 tree p1 = TYPE_ARG_TYPES (f1);
9168 tree p2 = TYPE_ARG_TYPES (f2);
9170 /* Check if cand1->fn and cand2->fn are versions of the same function. It
9171 is possible that cand1->fn and cand2->fn are function versions but of
9172 different functions. Check types to see if they are versions of the same
9174 if (compparms (p1, p2)
9175 && same_type_p (TREE_TYPE (f1), TREE_TYPE (f2)))
9177 /* Always make the version with the higher priority, more
9178 specialized, win. */
9179 gcc_assert (targetm.compare_version_priority);
9180 if (targetm.compare_version_priority (cand1->fn, cand2->fn) >= 0)
9187 /* If the two function declarations represent the same function (this can
9188 happen with declarations in multiple scopes and arg-dependent lookup),
9189 arbitrarily choose one. But first make sure the default args we're
9191 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
9192 && equal_functions (cand1->fn, cand2->fn))
9194 tree parms1 = TYPE_ARG_TYPES (TREE_TYPE (cand1->fn));
9195 tree parms2 = TYPE_ARG_TYPES (TREE_TYPE (cand2->fn));
9197 gcc_assert (!DECL_CONSTRUCTOR_P (cand1->fn));
9199 for (i = 0; i < len; ++i)
9201 /* Don't crash if the fn is variadic. */
9204 parms1 = TREE_CHAIN (parms1);
9205 parms2 = TREE_CHAIN (parms2);
9209 parms1 = TREE_CHAIN (parms1);
9211 parms2 = TREE_CHAIN (parms2);
9215 if (!cp_tree_equal (TREE_PURPOSE (parms1),
9216 TREE_PURPOSE (parms2)))
9220 if (complain & tf_error)
9222 if (permerror (input_location,
9223 "default argument mismatch in "
9224 "overload resolution"))
9226 inform (input_location,
9227 " candidate 1: %q+#F", cand1->fn);
9228 inform (input_location,
9229 " candidate 2: %q+#F", cand2->fn);
9236 add_warning (cand1, cand2);
9239 parms1 = TREE_CHAIN (parms1);
9240 parms2 = TREE_CHAIN (parms2);
9248 /* Extension: If the worst conversion for one candidate is worse than the
9249 worst conversion for the other, take the first. */
9250 if (!pedantic && (complain & tf_warning_or_error))
9252 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
9253 struct z_candidate *w = 0, *l = 0;
9255 for (i = 0; i < len; ++i)
9257 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
9258 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
9259 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
9260 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
9263 winner = 1, w = cand1, l = cand2;
9265 winner = -1, w = cand2, l = cand1;
9268 /* Don't choose a deleted function over ambiguity. */
9269 if (DECL_P (w->fn) && DECL_DELETED_FN (w->fn))
9273 pedwarn (input_location, 0,
9274 "ISO C++ says that these are ambiguous, even "
9275 "though the worst conversion for the first is better than "
9276 "the worst conversion for the second:");
9277 print_z_candidate (input_location, _("candidate 1:"), w);
9278 print_z_candidate (input_location, _("candidate 2:"), l);
9286 gcc_assert (!winner);
9290 /* Given a list of candidates for overloading, find the best one, if any.
9291 This algorithm has a worst case of O(2n) (winner is last), and a best
9292 case of O(n/2) (totally ambiguous); much better than a sorting
9295 static struct z_candidate *
9296 tourney (struct z_candidate *candidates, tsubst_flags_t complain)
9298 struct z_candidate *champ = candidates, *challenger;
9300 int champ_compared_to_predecessor = 0;
9302 /* Walk through the list once, comparing each current champ to the next
9303 candidate, knocking out a candidate or two with each comparison. */
9305 for (challenger = champ->next; challenger; )
9307 fate = joust (champ, challenger, 0, complain);
9309 challenger = challenger->next;
9314 champ = challenger->next;
9317 champ_compared_to_predecessor = 0;
9322 champ_compared_to_predecessor = 1;
9325 challenger = champ->next;
9329 /* Make sure the champ is better than all the candidates it hasn't yet
9330 been compared to. */
9332 for (challenger = candidates;
9334 && !(champ_compared_to_predecessor && challenger->next == champ);
9335 challenger = challenger->next)
9337 fate = joust (champ, challenger, 0, complain);
9345 /* Returns nonzero if things of type FROM can be converted to TO. */
9348 can_convert (tree to, tree from, tsubst_flags_t complain)
9350 tree arg = NULL_TREE;
9351 /* implicit_conversion only considers user-defined conversions
9352 if it has an expression for the call argument list. */
9353 if (CLASS_TYPE_P (from) || CLASS_TYPE_P (to))
9354 arg = build1 (CAST_EXPR, from, NULL_TREE);
9355 return can_convert_arg (to, from, arg, LOOKUP_IMPLICIT, complain);
9358 /* Returns nonzero if things of type FROM can be converted to TO with a
9359 standard conversion. */
9362 can_convert_standard (tree to, tree from, tsubst_flags_t complain)
9364 return can_convert_arg (to, from, NULL_TREE, LOOKUP_IMPLICIT, complain);
9367 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
9370 can_convert_arg (tree to, tree from, tree arg, int flags,
9371 tsubst_flags_t complain)
9377 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9378 p = conversion_obstack_alloc (0);
9379 /* We want to discard any access checks done for this test,
9380 as we might not be in the appropriate access context and
9381 we'll do the check again when we actually perform the
9383 push_deferring_access_checks (dk_deferred);
9385 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
9387 ok_p = (t && !t->bad_p);
9389 /* Discard the access checks now. */
9390 pop_deferring_access_checks ();
9391 /* Free all the conversions we allocated. */
9392 obstack_free (&conversion_obstack, p);
9397 /* Like can_convert_arg, but allows dubious conversions as well. */
9400 can_convert_arg_bad (tree to, tree from, tree arg, int flags,
9401 tsubst_flags_t complain)
9406 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9407 p = conversion_obstack_alloc (0);
9408 /* Try to perform the conversion. */
9409 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
9411 /* Free all the conversions we allocated. */
9412 obstack_free (&conversion_obstack, p);
9417 /* Convert EXPR to TYPE. Return the converted expression.
9419 Note that we allow bad conversions here because by the time we get to
9420 this point we are committed to doing the conversion. If we end up
9421 doing a bad conversion, convert_like will complain. */
9424 perform_implicit_conversion_flags (tree type, tree expr,
9425 tsubst_flags_t complain, int flags)
9429 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
9431 if (error_operand_p (expr))
9432 return error_mark_node;
9434 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9435 p = conversion_obstack_alloc (0);
9437 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
9443 if (complain & tf_error)
9445 /* If expr has unknown type, then it is an overloaded function.
9446 Call instantiate_type to get good error messages. */
9447 if (TREE_TYPE (expr) == unknown_type_node)
9448 instantiate_type (type, expr, complain);
9449 else if (invalid_nonstatic_memfn_p (expr, complain))
9450 /* We gave an error. */;
9452 error_at (loc, "could not convert %qE from %qT to %qT", expr,
9453 TREE_TYPE (expr), type);
9455 expr = error_mark_node;
9457 else if (processing_template_decl && conv->kind != ck_identity)
9459 /* In a template, we are only concerned about determining the
9460 type of non-dependent expressions, so we do not have to
9461 perform the actual conversion. But for initializers, we
9462 need to be able to perform it at instantiation
9463 (or instantiate_non_dependent_expr) time. */
9464 expr = build1 (IMPLICIT_CONV_EXPR, type, expr);
9465 if (!(flags & LOOKUP_ONLYCONVERTING))
9466 IMPLICIT_CONV_EXPR_DIRECT_INIT (expr) = true;
9469 expr = convert_like (conv, expr, complain);
9471 /* Free all the conversions we allocated. */
9472 obstack_free (&conversion_obstack, p);
9478 perform_implicit_conversion (tree type, tree expr, tsubst_flags_t complain)
9480 return perform_implicit_conversion_flags (type, expr, complain,
9484 /* Convert EXPR to TYPE (as a direct-initialization) if that is
9485 permitted. If the conversion is valid, the converted expression is
9486 returned. Otherwise, NULL_TREE is returned, except in the case
9487 that TYPE is a class type; in that case, an error is issued. If
9488 C_CAST_P is true, then this direct-initialization is taking
9489 place as part of a static_cast being attempted as part of a C-style
9493 perform_direct_initialization_if_possible (tree type,
9496 tsubst_flags_t complain)
9501 if (type == error_mark_node || error_operand_p (expr))
9502 return error_mark_node;
9505 If the destination type is a (possibly cv-qualified) class type:
9507 -- If the initialization is direct-initialization ...,
9508 constructors are considered. ... If no constructor applies, or
9509 the overload resolution is ambiguous, the initialization is
9511 if (CLASS_TYPE_P (type))
9513 vec<tree, va_gc> *args = make_tree_vector_single (expr);
9514 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
9515 &args, type, LOOKUP_NORMAL, complain);
9516 release_tree_vector (args);
9517 return build_cplus_new (type, expr, complain);
9520 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9521 p = conversion_obstack_alloc (0);
9523 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
9525 LOOKUP_NORMAL, complain);
9526 if (!conv || conv->bad_p)
9529 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
9530 /*issue_conversion_warnings=*/false,
9534 /* Free all the conversions we allocated. */
9535 obstack_free (&conversion_obstack, p);
9540 /* When initializing a reference that lasts longer than a full-expression,
9541 this special rule applies:
9545 The temporary to which the reference is bound or the temporary
9546 that is the complete object to which the reference is bound
9547 persists for the lifetime of the reference.
9549 The temporaries created during the evaluation of the expression
9550 initializing the reference, except the temporary to which the
9551 reference is bound, are destroyed at the end of the
9552 full-expression in which they are created.
9554 In that case, we store the converted expression into a new
9555 VAR_DECL in a new scope.
9557 However, we want to be careful not to create temporaries when
9558 they are not required. For example, given:
9561 struct D : public B {};
9565 there is no need to copy the return value from "f"; we can just
9566 extend its lifetime. Similarly, given:
9569 struct T { operator S(); };
9573 we can extend the lifetime of the return value of the conversion
9576 The next several functions are involved in this lifetime extension. */
9578 /* DECL is a VAR_DECL or FIELD_DECL whose type is a REFERENCE_TYPE. The
9579 reference is being bound to a temporary. Create and return a new
9580 VAR_DECL with the indicated TYPE; this variable will store the value to
9581 which the reference is bound. */
9584 make_temporary_var_for_ref_to_temp (tree decl, tree type)
9588 /* Create the variable. */
9589 var = create_temporary_var (type);
9591 /* Register the variable. */
9593 && (TREE_STATIC (decl) || DECL_THREAD_LOCAL_P (decl)))
9595 /* Namespace-scope or local static; give it a mangled name. */
9596 /* FIXME share comdat with decl? */
9599 TREE_STATIC (var) = TREE_STATIC (decl);
9600 set_decl_tls_model (var, DECL_TLS_MODEL (decl));
9601 name = mangle_ref_init_variable (decl);
9602 DECL_NAME (var) = name;
9603 SET_DECL_ASSEMBLER_NAME (var, name);
9604 var = pushdecl_top_level (var);
9607 /* Create a new cleanup level if necessary. */
9608 maybe_push_cleanup_level (type);
9613 /* EXPR is the initializer for a variable DECL of reference or
9614 std::initializer_list type. Create, push and return a new VAR_DECL
9615 for the initializer so that it will live as long as DECL. Any
9616 cleanup for the new variable is returned through CLEANUP, and the
9617 code to initialize the new variable is returned through INITP. */
9620 set_up_extended_ref_temp (tree decl, tree expr, vec<tree, va_gc> **cleanups,
9627 /* Create the temporary variable. */
9628 type = TREE_TYPE (expr);
9629 var = make_temporary_var_for_ref_to_temp (decl, type);
9630 layout_decl (var, 0);
9631 /* If the rvalue is the result of a function call it will be
9632 a TARGET_EXPR. If it is some other construct (such as a
9633 member access expression where the underlying object is
9634 itself the result of a function call), turn it into a
9635 TARGET_EXPR here. It is important that EXPR be a
9636 TARGET_EXPR below since otherwise the INIT_EXPR will
9637 attempt to make a bitwise copy of EXPR to initialize
9639 if (TREE_CODE (expr) != TARGET_EXPR)
9640 expr = get_target_expr (expr);
9642 if (TREE_CODE (decl) == FIELD_DECL
9643 && extra_warnings && !TREE_NO_WARNING (decl))
9645 warning (OPT_Wextra, "a temporary bound to %qD only persists "
9646 "until the constructor exits", decl);
9647 TREE_NO_WARNING (decl) = true;
9650 /* Recursively extend temps in this initializer. */
9651 TARGET_EXPR_INITIAL (expr)
9652 = extend_ref_init_temps (decl, TARGET_EXPR_INITIAL (expr), cleanups);
9654 /* Any reference temp has a non-trivial initializer. */
9655 DECL_NONTRIVIALLY_INITIALIZED_P (var) = true;
9657 /* If the initializer is constant, put it in DECL_INITIAL so we get
9658 static initialization and use in constant expressions. */
9659 init = maybe_constant_init (expr);
9660 if (TREE_CONSTANT (init))
9662 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
9664 /* 5.19 says that a constant expression can include an
9665 lvalue-rvalue conversion applied to "a glvalue of literal type
9666 that refers to a non-volatile temporary object initialized
9667 with a constant expression". Rather than try to communicate
9668 that this VAR_DECL is a temporary, just mark it constexpr.
9670 Currently this is only useful for initializer_list temporaries,
9671 since reference vars can't appear in constant expressions. */
9672 DECL_DECLARED_CONSTEXPR_P (var) = true;
9673 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var) = true;
9674 TREE_CONSTANT (var) = true;
9676 DECL_INITIAL (var) = init;
9680 /* Create the INIT_EXPR that will initialize the temporary
9682 init = split_nonconstant_init (var, expr);
9683 if (at_function_scope_p ())
9685 add_decl_expr (var);
9687 if (TREE_STATIC (var))
9688 init = add_stmt_to_compound (init, register_dtor_fn (var));
9691 tree cleanup = cxx_maybe_build_cleanup (var, tf_warning_or_error);
9693 vec_safe_push (*cleanups, cleanup);
9696 /* We must be careful to destroy the temporary only
9697 after its initialization has taken place. If the
9698 initialization throws an exception, then the
9699 destructor should not be run. We cannot simply
9700 transform INIT into something like:
9702 (INIT, ({ CLEANUP_STMT; }))
9704 because emit_local_var always treats the
9705 initializer as a full-expression. Thus, the
9706 destructor would run too early; it would run at the
9707 end of initializing the reference variable, rather
9708 than at the end of the block enclosing the
9711 The solution is to pass back a cleanup expression
9712 which the caller is responsible for attaching to
9713 the statement tree. */
9717 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
9718 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
9720 if (DECL_THREAD_LOCAL_P (var))
9721 tls_aggregates = tree_cons (NULL_TREE, var,
9724 static_aggregates = tree_cons (NULL_TREE, var,
9728 /* Check whether the dtor is callable. */
9729 cxx_maybe_build_cleanup (var, tf_warning_or_error);
9731 /* Avoid -Wunused-variable warning (c++/38958). */
9732 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
9733 && TREE_CODE (decl) == VAR_DECL)
9734 TREE_USED (decl) = DECL_READ_P (decl) = true;
9740 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
9741 initializing a variable of that TYPE. */
9744 initialize_reference (tree type, tree expr,
9745 int flags, tsubst_flags_t complain)
9749 location_t loc = EXPR_LOC_OR_LOC (expr, input_location);
9751 if (type == error_mark_node || error_operand_p (expr))
9752 return error_mark_node;
9754 /* Get the high-water mark for the CONVERSION_OBSTACK. */
9755 p = conversion_obstack_alloc (0);
9757 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
9759 if (!conv || conv->bad_p)
9761 if (complain & tf_error)
9764 convert_like (conv, expr, complain);
9765 else if (!CP_TYPE_CONST_P (TREE_TYPE (type))
9766 && !TYPE_REF_IS_RVALUE (type)
9767 && !real_lvalue_p (expr))
9768 error_at (loc, "invalid initialization of non-const reference of "
9769 "type %qT from an rvalue of type %qT",
9770 type, TREE_TYPE (expr));
9772 error_at (loc, "invalid initialization of reference of type "
9773 "%qT from expression of type %qT", type,
9776 return error_mark_node;
9779 if (conv->kind == ck_ref_bind)
9780 /* Perform the conversion. */
9781 expr = convert_like (conv, expr, complain);
9782 else if (conv->kind == ck_ambig)
9783 /* We gave an error in build_user_type_conversion_1. */
9784 expr = error_mark_node;
9788 /* Free all the conversions we allocated. */
9789 obstack_free (&conversion_obstack, p);
9794 /* Subroutine of extend_ref_init_temps. Possibly extend one initializer,
9795 which is bound either to a reference or a std::initializer_list. */
9798 extend_ref_init_temps_1 (tree decl, tree init, vec<tree, va_gc> **cleanups)
9803 if (TREE_CODE (sub) == COMPOUND_EXPR)
9805 TREE_OPERAND (sub, 1)
9806 = extend_ref_init_temps_1 (decl, TREE_OPERAND (sub, 1), cleanups);
9809 if (TREE_CODE (sub) != ADDR_EXPR)
9811 /* Deal with binding to a subobject. */
9812 for (p = &TREE_OPERAND (sub, 0); TREE_CODE (*p) == COMPONENT_REF; )
9813 p = &TREE_OPERAND (*p, 0);
9814 if (TREE_CODE (*p) == TARGET_EXPR)
9816 tree subinit = NULL_TREE;
9817 *p = set_up_extended_ref_temp (decl, *p, cleanups, &subinit);
9818 recompute_tree_invariant_for_addr_expr (sub);
9820 init = fold_convert (TREE_TYPE (init), sub);
9822 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), subinit, init);
9827 /* INIT is part of the initializer for DECL. If there are any
9828 reference or initializer lists being initialized, extend their
9829 lifetime to match that of DECL. */
9832 extend_ref_init_temps (tree decl, tree init, vec<tree, va_gc> **cleanups)
9834 tree type = TREE_TYPE (init);
9835 if (processing_template_decl)
9837 if (TREE_CODE (type) == REFERENCE_TYPE)
9838 init = extend_ref_init_temps_1 (decl, init, cleanups);
9839 else if (is_std_init_list (type))
9841 /* The temporary array underlying a std::initializer_list
9842 is handled like a reference temporary. */
9844 if (TREE_CODE (ctor) == TARGET_EXPR)
9845 ctor = TARGET_EXPR_INITIAL (ctor);
9846 if (TREE_CODE (ctor) == CONSTRUCTOR)
9848 tree array = CONSTRUCTOR_ELT (ctor, 0)->value;
9849 array = extend_ref_init_temps_1 (decl, array, cleanups);
9850 CONSTRUCTOR_ELT (ctor, 0)->value = array;
9853 else if (TREE_CODE (init) == CONSTRUCTOR)
9857 vec<constructor_elt, va_gc> *elts = CONSTRUCTOR_ELTS (init);
9858 FOR_EACH_VEC_SAFE_ELT (elts, i, p)
9859 p->value = extend_ref_init_temps (decl, p->value, cleanups);
9865 /* Returns true iff an initializer for TYPE could contain temporaries that
9866 need to be extended because they are bound to references or
9867 std::initializer_list. */
9870 type_has_extended_temps (tree type)
9872 type = strip_array_types (type);
9873 if (TREE_CODE (type) == REFERENCE_TYPE)
9875 if (CLASS_TYPE_P (type))
9877 if (is_std_init_list (type))
9879 for (tree f = next_initializable_field (TYPE_FIELDS (type));
9880 f; f = next_initializable_field (DECL_CHAIN (f)))
9881 if (type_has_extended_temps (TREE_TYPE (f)))
9887 /* Returns true iff TYPE is some variant of std::initializer_list. */
9890 is_std_init_list (tree type)
9892 /* Look through typedefs. */
9895 if (cxx_dialect == cxx98)
9897 type = TYPE_MAIN_VARIANT (type);
9898 return (CLASS_TYPE_P (type)
9899 && CP_TYPE_CONTEXT (type) == std_node
9900 && strcmp (TYPE_NAME_STRING (type), "initializer_list") == 0);
9903 /* Returns true iff DECL is a list constructor: i.e. a constructor which
9904 will accept an argument list of a single std::initializer_list<T>. */
9907 is_list_ctor (tree decl)
9909 tree args = FUNCTION_FIRST_USER_PARMTYPE (decl);
9912 if (!args || args == void_list_node)
9915 arg = non_reference (TREE_VALUE (args));
9916 if (!is_std_init_list (arg))
9919 args = TREE_CHAIN (args);
9921 if (args && args != void_list_node && !TREE_PURPOSE (args))
9922 /* There are more non-defaulted parms. */
9928 #include "gt-cp-call.h"