1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com) and
6 modified by Brendan Kehoe (brendan@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING. If not, write to
22 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
23 Boston, MA 02110-1301, USA. */
26 /* High-level class interface. */
30 #include "coretypes.h"
39 #include "diagnostic.h"
43 #include "langhooks.h"
45 /* The various kinds of conversion. */
47 typedef enum conversion_kind {
61 /* The rank of the conversion. Order of the enumerals matters; better
62 conversions should come earlier in the list. */
64 typedef enum conversion_rank {
75 /* An implicit conversion sequence, in the sense of [over.best.ics].
76 The first conversion to be performed is at the end of the chain.
77 That conversion is always a cr_identity conversion. */
79 typedef struct conversion conversion;
81 /* The kind of conversion represented by this step. */
83 /* The rank of this conversion. */
85 BOOL_BITFIELD user_conv_p : 1;
86 BOOL_BITFIELD ellipsis_p : 1;
87 BOOL_BITFIELD this_p : 1;
88 BOOL_BITFIELD bad_p : 1;
89 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
90 temporary should be created to hold the result of the
92 BOOL_BITFIELD need_temporary_p : 1;
93 /* If KIND is ck_identity or ck_base_conv, true to indicate that the
94 copy constructor must be accessible, even though it is not being
96 BOOL_BITFIELD check_copy_constructor_p : 1;
97 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
98 from a pointer-to-derived to pointer-to-base is being performed. */
99 BOOL_BITFIELD base_p : 1;
100 /* If KIND is ck_ref_bind, true when either an lvalue reference is
101 being bound to an lvalue expression or an rvalue reference is
102 being bound to an rvalue expression. */
103 BOOL_BITFIELD rvaluedness_matches_p: 1;
104 /* The type of the expression resulting from the conversion. */
107 /* The next conversion in the chain. Since the conversions are
108 arranged from outermost to innermost, the NEXT conversion will
109 actually be performed before this conversion. This variant is
110 used only when KIND is neither ck_identity nor ck_ambig. */
112 /* The expression at the beginning of the conversion chain. This
113 variant is used only if KIND is ck_identity or ck_ambig. */
116 /* The function candidate corresponding to this conversion
117 sequence. This field is only used if KIND is ck_user. */
118 struct z_candidate *cand;
121 #define CONVERSION_RANK(NODE) \
122 ((NODE)->bad_p ? cr_bad \
123 : (NODE)->ellipsis_p ? cr_ellipsis \
124 : (NODE)->user_conv_p ? cr_user \
127 static struct obstack conversion_obstack;
128 static bool conversion_obstack_initialized;
130 static struct z_candidate * tourney (struct z_candidate *);
131 static int equal_functions (tree, tree);
132 static int joust (struct z_candidate *, struct z_candidate *, bool);
133 static int compare_ics (conversion *, conversion *);
134 static tree build_over_call (struct z_candidate *, int);
135 static tree build_java_interface_fn_ref (tree, tree);
136 #define convert_like(CONV, EXPR) \
137 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
138 /*issue_conversion_warnings=*/true, \
140 #define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
141 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
142 /*issue_conversion_warnings=*/true, \
144 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
146 static void op_error (enum tree_code, enum tree_code, tree, tree,
148 static tree build_object_call (tree, tree);
149 static tree resolve_args (tree);
150 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
151 static void print_z_candidate (const char *, struct z_candidate *);
152 static void print_z_candidates (struct z_candidate *);
153 static tree build_this (tree);
154 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
155 static bool any_strictly_viable (struct z_candidate *);
156 static struct z_candidate *add_template_candidate
157 (struct z_candidate **, tree, tree, tree, tree, tree,
158 tree, tree, int, unification_kind_t);
159 static struct z_candidate *add_template_candidate_real
160 (struct z_candidate **, tree, tree, tree, tree, tree,
161 tree, tree, int, tree, unification_kind_t);
162 static struct z_candidate *add_template_conv_candidate
163 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
164 static void add_builtin_candidates
165 (struct z_candidate **, enum tree_code, enum tree_code,
167 static void add_builtin_candidate
168 (struct z_candidate **, enum tree_code, enum tree_code,
169 tree, tree, tree, tree *, tree *, int);
170 static bool is_complete (tree);
171 static void build_builtin_candidate
172 (struct z_candidate **, tree, tree, tree, tree *, tree *,
174 static struct z_candidate *add_conv_candidate
175 (struct z_candidate **, tree, tree, tree, tree, tree);
176 static struct z_candidate *add_function_candidate
177 (struct z_candidate **, tree, tree, tree, tree, tree, int);
178 static conversion *implicit_conversion (tree, tree, tree, bool, int);
179 static conversion *standard_conversion (tree, tree, tree, bool, int);
180 static conversion *reference_binding (tree, tree, tree, bool, int);
181 static conversion *build_conv (conversion_kind, tree, conversion *);
182 static bool is_subseq (conversion *, conversion *);
183 static conversion *maybe_handle_ref_bind (conversion **);
184 static void maybe_handle_implicit_object (conversion **);
185 static struct z_candidate *add_candidate
186 (struct z_candidate **, tree, tree, size_t,
187 conversion **, tree, tree, int);
188 static tree source_type (conversion *);
189 static void add_warning (struct z_candidate *, struct z_candidate *);
190 static bool reference_related_p (tree, tree);
191 static bool reference_compatible_p (tree, tree);
192 static conversion *convert_class_to_reference (tree, tree, tree);
193 static conversion *direct_reference_binding (tree, conversion *);
194 static bool promoted_arithmetic_type_p (tree);
195 static conversion *conditional_conversion (tree, tree);
196 static char *name_as_c_string (tree, tree, bool *);
197 static tree call_builtin_trap (void);
198 static tree prep_operand (tree);
199 static void add_candidates (tree, tree, tree, bool, tree, tree,
200 int, struct z_candidate **);
201 static conversion *merge_conversion_sequences (conversion *, conversion *);
202 static bool magic_varargs_p (tree);
203 typedef void (*diagnostic_fn_t) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
204 static tree build_temp (tree, tree, int, diagnostic_fn_t *);
205 static void check_constructor_callable (tree, tree);
207 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
208 NAME can take many forms... */
211 check_dtor_name (tree basetype, tree name)
213 /* Just accept something we've already complained about. */
214 if (name == error_mark_node)
217 if (TREE_CODE (name) == TYPE_DECL)
218 name = TREE_TYPE (name);
219 else if (TYPE_P (name))
221 else if (TREE_CODE (name) == IDENTIFIER_NODE)
223 if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
224 || (TREE_CODE (basetype) == ENUMERAL_TYPE
225 && name == TYPE_IDENTIFIER (basetype)))
228 name = get_type_value (name);
234 template <class T> struct S { ~S(); };
238 NAME will be a class template. */
239 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
245 return same_type_p (TYPE_MAIN_VARIANT (basetype), TYPE_MAIN_VARIANT (name));
248 /* We want the address of a function or method. We avoid creating a
249 pointer-to-member function. */
252 build_addr_func (tree function)
254 tree type = TREE_TYPE (function);
256 /* We have to do these by hand to avoid real pointer to member
258 if (TREE_CODE (type) == METHOD_TYPE)
260 if (TREE_CODE (function) == OFFSET_REF)
262 tree object = build_address (TREE_OPERAND (function, 0));
263 return get_member_function_from_ptrfunc (&object,
264 TREE_OPERAND (function, 1));
266 function = build_address (function);
269 function = decay_conversion (function);
274 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
275 POINTER_TYPE to those. Note, pointer to member function types
276 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
277 two variants. build_call_a is the primitive taking an array of
278 arguments, while build_call_n is a wrapper that handles varargs. */
281 build_call_n (tree function, int n, ...)
284 return build_call_a (function, 0, NULL);
287 tree *argarray = (tree *) alloca (n * sizeof (tree));
292 for (i = 0; i < n; i++)
293 argarray[i] = va_arg (ap, tree);
295 return build_call_a (function, n, argarray);
300 build_call_a (tree function, int n, tree *argarray)
302 int is_constructor = 0;
309 function = build_addr_func (function);
311 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
312 fntype = TREE_TYPE (TREE_TYPE (function));
313 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
314 || TREE_CODE (fntype) == METHOD_TYPE);
315 result_type = TREE_TYPE (fntype);
317 if (TREE_CODE (function) == ADDR_EXPR
318 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
320 decl = TREE_OPERAND (function, 0);
321 if (!TREE_USED (decl))
323 /* We invoke build_call directly for several library
324 functions. These may have been declared normally if
325 we're building libgcc, so we can't just check
327 gcc_assert (DECL_ARTIFICIAL (decl)
328 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
336 /* We check both the decl and the type; a function may be known not to
337 throw without being declared throw(). */
338 nothrow = ((decl && TREE_NOTHROW (decl))
339 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
341 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
342 current_function_returns_abnormally = 1;
344 if (decl && TREE_DEPRECATED (decl))
345 warn_deprecated_use (decl);
346 require_complete_eh_spec_types (fntype, decl);
348 if (decl && DECL_CONSTRUCTOR_P (decl))
351 /* Don't pass empty class objects by value. This is useful
352 for tags in STL, which are used to control overload resolution.
353 We don't need to handle other cases of copying empty classes. */
354 if (! decl || ! DECL_BUILT_IN (decl))
355 for (i = 0; i < n; i++)
356 if (is_empty_class (TREE_TYPE (argarray[i]))
357 && ! TREE_ADDRESSABLE (TREE_TYPE (argarray[i])))
359 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (argarray[i]));
360 argarray[i] = build2 (COMPOUND_EXPR, TREE_TYPE (t),
364 function = build_call_array (result_type, function, n, argarray);
365 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
366 TREE_NOTHROW (function) = nothrow;
371 /* Build something of the form ptr->method (args)
372 or object.method (args). This can also build
373 calls to constructors, and find friends.
375 Member functions always take their class variable
378 INSTANCE is a class instance.
380 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
382 PARMS help to figure out what that NAME really refers to.
384 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
385 down to the real instance type to use for access checking. We need this
386 information to get protected accesses correct.
388 FLAGS is the logical disjunction of zero or more LOOKUP_
389 flags. See cp-tree.h for more info.
391 If this is all OK, calls build_function_call with the resolved
394 This function must also handle being called to perform
395 initialization, promotion/coercion of arguments, and
396 instantiation of default parameters.
398 Note that NAME may refer to an instance variable name. If
399 `operator()()' is defined for the type of that field, then we return
402 /* New overloading code. */
404 typedef struct z_candidate z_candidate;
406 typedef struct candidate_warning candidate_warning;
407 struct candidate_warning {
409 candidate_warning *next;
413 /* The FUNCTION_DECL that will be called if this candidate is
414 selected by overload resolution. */
416 /* The arguments to use when calling this function. */
418 /* The implicit conversion sequences for each of the arguments to
421 /* The number of implicit conversion sequences. */
423 /* If FN is a user-defined conversion, the standard conversion
424 sequence from the type returned by FN to the desired destination
426 conversion *second_conv;
428 /* If FN is a member function, the binfo indicating the path used to
429 qualify the name of FN at the call site. This path is used to
430 determine whether or not FN is accessible if it is selected by
431 overload resolution. The DECL_CONTEXT of FN will always be a
432 (possibly improper) base of this binfo. */
434 /* If FN is a non-static member function, the binfo indicating the
435 subobject to which the `this' pointer should be converted if FN
436 is selected by overload resolution. The type pointed to the by
437 the `this' pointer must correspond to the most derived class
438 indicated by the CONVERSION_PATH. */
439 tree conversion_path;
441 candidate_warning *warnings;
445 /* Returns true iff T is a null pointer constant in the sense of
449 null_ptr_cst_p (tree t)
453 A null pointer constant is an integral constant expression
454 (_expr.const_) rvalue of integer type that evaluates to zero. */
455 t = integral_constant_value (t);
458 if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t))
461 if (!TREE_OVERFLOW (t))
467 /* Returns nonzero if PARMLIST consists of only default parms and/or
471 sufficient_parms_p (tree parmlist)
473 for (; parmlist && parmlist != void_list_node;
474 parmlist = TREE_CHAIN (parmlist))
475 if (!TREE_PURPOSE (parmlist))
480 /* Allocate N bytes of memory from the conversion obstack. The memory
481 is zeroed before being returned. */
484 conversion_obstack_alloc (size_t n)
487 if (!conversion_obstack_initialized)
489 gcc_obstack_init (&conversion_obstack);
490 conversion_obstack_initialized = true;
492 p = obstack_alloc (&conversion_obstack, n);
497 /* Dynamically allocate a conversion. */
500 alloc_conversion (conversion_kind kind)
503 c = (conversion *) conversion_obstack_alloc (sizeof (conversion));
508 #ifdef ENABLE_CHECKING
510 /* Make sure that all memory on the conversion obstack has been
514 validate_conversion_obstack (void)
516 if (conversion_obstack_initialized)
517 gcc_assert ((obstack_next_free (&conversion_obstack)
518 == obstack_base (&conversion_obstack)));
521 #endif /* ENABLE_CHECKING */
523 /* Dynamically allocate an array of N conversions. */
526 alloc_conversions (size_t n)
528 return (conversion **) conversion_obstack_alloc (n * sizeof (conversion *));
532 build_conv (conversion_kind code, tree type, conversion *from)
535 conversion_rank rank = CONVERSION_RANK (from);
537 /* We can't use buildl1 here because CODE could be USER_CONV, which
538 takes two arguments. In that case, the caller is responsible for
539 filling in the second argument. */
540 t = alloc_conversion (code);
563 t->user_conv_p = (code == ck_user || from->user_conv_p);
564 t->bad_p = from->bad_p;
569 /* Build a representation of the identity conversion from EXPR to
570 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
573 build_identity_conv (tree type, tree expr)
577 c = alloc_conversion (ck_identity);
584 /* Converting from EXPR to TYPE was ambiguous in the sense that there
585 were multiple user-defined conversions to accomplish the job.
586 Build a conversion that indicates that ambiguity. */
589 build_ambiguous_conv (tree type, tree expr)
593 c = alloc_conversion (ck_ambig);
601 strip_top_quals (tree t)
603 if (TREE_CODE (t) == ARRAY_TYPE)
605 return cp_build_qualified_type (t, 0);
608 /* Returns the standard conversion path (see [conv]) from type FROM to type
609 TO, if any. For proper handling of null pointer constants, you must
610 also pass the expression EXPR to convert from. If C_CAST_P is true,
611 this conversion is coming from a C-style cast. */
614 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
617 enum tree_code fcode, tcode;
619 bool fromref = false;
621 to = non_reference (to);
622 if (TREE_CODE (from) == REFERENCE_TYPE)
625 from = TREE_TYPE (from);
627 to = strip_top_quals (to);
628 from = strip_top_quals (from);
630 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
631 && expr && type_unknown_p (expr))
633 expr = instantiate_type (to, expr, tf_conv);
634 if (expr == error_mark_node)
636 from = TREE_TYPE (expr);
639 fcode = TREE_CODE (from);
640 tcode = TREE_CODE (to);
642 conv = build_identity_conv (from, expr);
643 if (fcode == FUNCTION_TYPE || fcode == ARRAY_TYPE)
645 from = type_decays_to (from);
646 fcode = TREE_CODE (from);
647 conv = build_conv (ck_lvalue, from, conv);
649 else if (fromref || (expr && lvalue_p (expr)))
654 bitfield_type = is_bitfield_expr_with_lowered_type (expr);
657 from = strip_top_quals (bitfield_type);
658 fcode = TREE_CODE (from);
661 conv = build_conv (ck_rvalue, from, conv);
664 /* Allow conversion between `__complex__' data types. */
665 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
667 /* The standard conversion sequence to convert FROM to TO is
668 the standard conversion sequence to perform componentwise
670 conversion *part_conv = standard_conversion
671 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
675 conv = build_conv (part_conv->kind, to, conv);
676 conv->rank = part_conv->rank;
684 if (same_type_p (from, to))
687 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
688 && expr && null_ptr_cst_p (expr))
689 conv = build_conv (ck_std, to, conv);
690 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
691 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
693 /* For backwards brain damage compatibility, allow interconversion of
694 pointers and integers with a pedwarn. */
695 conv = build_conv (ck_std, to, conv);
698 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
700 /* For backwards brain damage compatibility, allow interconversion of
701 enums and integers with a pedwarn. */
702 conv = build_conv (ck_std, to, conv);
705 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
706 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
711 if (tcode == POINTER_TYPE
712 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
715 else if (VOID_TYPE_P (TREE_TYPE (to))
716 && !TYPE_PTRMEM_P (from)
717 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
719 from = build_pointer_type
720 (cp_build_qualified_type (void_type_node,
721 cp_type_quals (TREE_TYPE (from))));
722 conv = build_conv (ck_ptr, from, conv);
724 else if (TYPE_PTRMEM_P (from))
726 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
727 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
729 if (DERIVED_FROM_P (fbase, tbase)
730 && (same_type_ignoring_top_level_qualifiers_p
731 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
732 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
734 from = build_ptrmem_type (tbase,
735 TYPE_PTRMEM_POINTED_TO_TYPE (from));
736 conv = build_conv (ck_pmem, from, conv);
738 else if (!same_type_p (fbase, tbase))
741 else if (IS_AGGR_TYPE (TREE_TYPE (from))
742 && IS_AGGR_TYPE (TREE_TYPE (to))
745 An rvalue of type "pointer to cv D," where D is a
746 class type, can be converted to an rvalue of type
747 "pointer to cv B," where B is a base class (clause
748 _class.derived_) of D. If B is an inaccessible
749 (clause _class.access_) or ambiguous
750 (_class.member.lookup_) base class of D, a program
751 that necessitates this conversion is ill-formed.
752 Therefore, we use DERIVED_FROM_P, and do not check
753 access or uniqueness. */
754 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from))
755 /* If FROM is not yet complete, then we must be parsing
756 the body of a class. We know what's derived from
757 what, but we can't actually perform a
758 derived-to-base conversion. For example, in:
760 struct D : public B {
761 static const int i = sizeof((B*)(D*)0);
764 the D*-to-B* conversion is a reinterpret_cast, not a
766 && COMPLETE_TYPE_P (TREE_TYPE (from)))
769 cp_build_qualified_type (TREE_TYPE (to),
770 cp_type_quals (TREE_TYPE (from)));
771 from = build_pointer_type (from);
772 conv = build_conv (ck_ptr, from, conv);
776 if (tcode == POINTER_TYPE)
778 to_pointee = TREE_TYPE (to);
779 from_pointee = TREE_TYPE (from);
783 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
784 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
787 if (same_type_p (from, to))
789 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
790 /* In a C-style cast, we ignore CV-qualification because we
791 are allowed to perform a static_cast followed by a
793 conv = build_conv (ck_qual, to, conv);
794 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
795 conv = build_conv (ck_qual, to, conv);
796 else if (expr && string_conv_p (to, expr, 0))
797 /* converting from string constant to char *. */
798 conv = build_conv (ck_qual, to, conv);
799 else if (ptr_reasonably_similar (to_pointee, from_pointee))
801 conv = build_conv (ck_ptr, to, conv);
809 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
811 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
812 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
813 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
814 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
816 if (!DERIVED_FROM_P (fbase, tbase)
817 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
818 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
819 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
820 || cp_type_quals (fbase) != cp_type_quals (tbase))
823 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
824 from = build_method_type_directly (from,
826 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
827 from = build_ptrmemfunc_type (build_pointer_type (from));
828 conv = build_conv (ck_pmem, from, conv);
831 else if (tcode == BOOLEAN_TYPE)
835 An rvalue of arithmetic, enumeration, pointer, or pointer to
836 member type can be converted to an rvalue of type bool. */
837 if (ARITHMETIC_TYPE_P (from)
838 || fcode == ENUMERAL_TYPE
839 || fcode == POINTER_TYPE
840 || TYPE_PTR_TO_MEMBER_P (from))
842 conv = build_conv (ck_std, to, conv);
843 if (fcode == POINTER_TYPE
844 || TYPE_PTRMEM_P (from)
845 || (TYPE_PTRMEMFUNC_P (from)
846 && conv->rank < cr_pbool))
847 conv->rank = cr_pbool;
853 /* We don't check for ENUMERAL_TYPE here because there are no standard
854 conversions to enum type. */
855 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
856 || tcode == REAL_TYPE)
858 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
860 conv = build_conv (ck_std, to, conv);
862 /* Give this a better rank if it's a promotion. */
863 if (same_type_p (to, type_promotes_to (from))
864 && conv->u.next->rank <= cr_promotion)
865 conv->rank = cr_promotion;
867 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
868 && vector_types_convertible_p (from, to, false))
869 return build_conv (ck_std, to, conv);
870 else if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE)
871 && IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
872 && is_properly_derived_from (from, to))
874 if (conv->kind == ck_rvalue)
876 conv = build_conv (ck_base, to, conv);
877 /* The derived-to-base conversion indicates the initialization
878 of a parameter with base type from an object of a derived
879 type. A temporary object is created to hold the result of
881 conv->need_temporary_p = true;
889 /* Returns nonzero if T1 is reference-related to T2. */
892 reference_related_p (tree t1, tree t2)
894 t1 = TYPE_MAIN_VARIANT (t1);
895 t2 = TYPE_MAIN_VARIANT (t2);
899 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
900 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
902 return (same_type_p (t1, t2)
903 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
904 && DERIVED_FROM_P (t1, t2)));
907 /* Returns nonzero if T1 is reference-compatible with T2. */
910 reference_compatible_p (tree t1, tree t2)
914 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
915 reference-related to T2 and cv1 is the same cv-qualification as,
916 or greater cv-qualification than, cv2. */
917 return (reference_related_p (t1, t2)
918 && at_least_as_qualified_p (t1, t2));
921 /* Determine whether or not the EXPR (of class type S) can be
922 converted to T as in [over.match.ref]. */
925 convert_class_to_reference (tree reference_type, tree s, tree expr)
931 struct z_candidate *candidates;
932 struct z_candidate *cand;
935 conversions = lookup_conversions (s);
941 Assuming that "cv1 T" is the underlying type of the reference
942 being initialized, and "cv S" is the type of the initializer
943 expression, with S a class type, the candidate functions are
946 --The conversion functions of S and its base classes are
947 considered. Those that are not hidden within S and yield type
948 "reference to cv2 T2", where "cv1 T" is reference-compatible
949 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
951 The argument list has one argument, which is the initializer
956 /* Conceptually, we should take the address of EXPR and put it in
957 the argument list. Unfortunately, however, that can result in
958 error messages, which we should not issue now because we are just
959 trying to find a conversion operator. Therefore, we use NULL,
960 cast to the appropriate type. */
961 arglist = build_int_cst (build_pointer_type (s), 0);
962 arglist = build_tree_list (NULL_TREE, arglist);
964 t = TREE_TYPE (reference_type);
968 tree fns = TREE_VALUE (conversions);
970 for (; fns; fns = OVL_NEXT (fns))
972 tree f = OVL_CURRENT (fns);
973 tree t2 = TREE_TYPE (TREE_TYPE (f));
977 /* If this is a template function, try to get an exact
979 if (TREE_CODE (f) == TEMPLATE_DECL)
981 cand = add_template_candidate (&candidates,
987 TREE_PURPOSE (conversions),
993 /* Now, see if the conversion function really returns
994 an lvalue of the appropriate type. From the
995 point of view of unification, simply returning an
996 rvalue of the right type is good enough. */
998 t2 = TREE_TYPE (TREE_TYPE (f));
999 if (TREE_CODE (t2) != REFERENCE_TYPE
1000 || !reference_compatible_p (t, TREE_TYPE (t2)))
1002 candidates = candidates->next;
1007 else if (TREE_CODE (t2) == REFERENCE_TYPE
1008 && reference_compatible_p (t, TREE_TYPE (t2)))
1009 cand = add_function_candidate (&candidates, f, s, arglist,
1011 TREE_PURPOSE (conversions),
1016 conversion *identity_conv;
1017 /* Build a standard conversion sequence indicating the
1018 binding from the reference type returned by the
1019 function to the desired REFERENCE_TYPE. */
1021 = build_identity_conv (TREE_TYPE (TREE_TYPE
1022 (TREE_TYPE (cand->fn))),
1025 = (direct_reference_binding
1026 (reference_type, identity_conv));
1027 cand->second_conv->rvaluedness_matches_p
1028 = TYPE_REF_IS_RVALUE (TREE_TYPE (TREE_TYPE (cand->fn)))
1029 == TYPE_REF_IS_RVALUE (reference_type);
1030 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
1033 conversions = TREE_CHAIN (conversions);
1036 candidates = splice_viable (candidates, pedantic, &any_viable_p);
1037 /* If none of the conversion functions worked out, let our caller
1042 cand = tourney (candidates);
1046 /* Now that we know that this is the function we're going to use fix
1047 the dummy first argument. */
1048 cand->args = tree_cons (NULL_TREE,
1050 TREE_CHAIN (cand->args));
1052 /* Build a user-defined conversion sequence representing the
1054 conv = build_conv (ck_user,
1055 TREE_TYPE (TREE_TYPE (cand->fn)),
1056 build_identity_conv (TREE_TYPE (expr), expr));
1059 /* Merge it with the standard conversion sequence from the
1060 conversion function's return type to the desired type. */
1061 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1063 if (cand->viable == -1)
1066 return cand->second_conv;
1069 /* A reference of the indicated TYPE is being bound directly to the
1070 expression represented by the implicit conversion sequence CONV.
1071 Return a conversion sequence for this binding. */
1074 direct_reference_binding (tree type, conversion *conv)
1078 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1079 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1081 t = TREE_TYPE (type);
1085 When a parameter of reference type binds directly
1086 (_dcl.init.ref_) to an argument expression, the implicit
1087 conversion sequence is the identity conversion, unless the
1088 argument expression has a type that is a derived class of the
1089 parameter type, in which case the implicit conversion sequence is
1090 a derived-to-base Conversion.
1092 If the parameter binds directly to the result of applying a
1093 conversion function to the argument expression, the implicit
1094 conversion sequence is a user-defined conversion sequence
1095 (_over.ics.user_), with the second standard conversion sequence
1096 either an identity conversion or, if the conversion function
1097 returns an entity of a type that is a derived class of the
1098 parameter type, a derived-to-base conversion. */
1099 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1101 /* Represent the derived-to-base conversion. */
1102 conv = build_conv (ck_base, t, conv);
1103 /* We will actually be binding to the base-class subobject in
1104 the derived class, so we mark this conversion appropriately.
1105 That way, convert_like knows not to generate a temporary. */
1106 conv->need_temporary_p = false;
1108 return build_conv (ck_ref_bind, type, conv);
1111 /* Returns the conversion path from type FROM to reference type TO for
1112 purposes of reference binding. For lvalue binding, either pass a
1113 reference type to FROM or an lvalue expression to EXPR. If the
1114 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1115 the conversion returned. If C_CAST_P is true, this
1116 conversion is coming from a C-style cast. */
1119 reference_binding (tree rto, tree rfrom, tree expr, bool c_cast_p, int flags)
1121 conversion *conv = NULL;
1122 tree to = TREE_TYPE (rto);
1126 cp_lvalue_kind lvalue_p = clk_none;
1128 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1130 expr = instantiate_type (to, expr, tf_none);
1131 if (expr == error_mark_node)
1133 from = TREE_TYPE (expr);
1136 if (TREE_CODE (from) == REFERENCE_TYPE)
1138 /* Anything with reference type is an lvalue. */
1139 lvalue_p = clk_ordinary;
1140 from = TREE_TYPE (from);
1143 lvalue_p = real_lvalue_p (expr);
1145 /* Figure out whether or not the types are reference-related and
1146 reference compatible. We have do do this after stripping
1147 references from FROM. */
1148 related_p = reference_related_p (to, from);
1149 /* If this is a C cast, first convert to an appropriately qualified
1150 type, so that we can later do a const_cast to the desired type. */
1151 if (related_p && c_cast_p
1152 && !at_least_as_qualified_p (to, from))
1153 to = build_qualified_type (to, cp_type_quals (from));
1154 compatible_p = reference_compatible_p (to, from);
1156 /* Directly bind reference when target expression's type is compatible with
1157 the reference and expression is an lvalue. In C++0x, the wording in
1158 [8.5.3/5 dcl.init.ref] is changed to also allow direct bindings for const
1159 and rvalue references to rvalues of compatible class type, as part of
1163 || ((cxx_dialect != cxx98)
1164 && (CP_TYPE_CONST_NON_VOLATILE_P(to) || TYPE_REF_IS_RVALUE (rto))
1165 && CLASS_TYPE_P (from))))
1169 If the initializer expression
1171 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1172 is reference-compatible with "cv2 T2,"
1174 the reference is bound directly to the initializer expression
1176 conv = build_identity_conv (from, expr);
1177 conv = direct_reference_binding (rto, conv);
1179 if (flags & LOOKUP_PREFER_RVALUE)
1180 /* The top-level caller requested that we pretend that the lvalue
1181 be treated as an rvalue. */
1182 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1184 conv->rvaluedness_matches_p
1185 = (TYPE_REF_IS_RVALUE (rto) == !lvalue_p);
1187 if ((lvalue_p & clk_bitfield) != 0
1188 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1189 /* For the purposes of overload resolution, we ignore the fact
1190 this expression is a bitfield or packed field. (In particular,
1191 [over.ics.ref] says specifically that a function with a
1192 non-const reference parameter is viable even if the
1193 argument is a bitfield.)
1195 However, when we actually call the function we must create
1196 a temporary to which to bind the reference. If the
1197 reference is volatile, or isn't const, then we cannot make
1198 a temporary, so we just issue an error when the conversion
1200 conv->need_temporary_p = true;
1204 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1208 If the initializer expression
1210 -- has a class type (i.e., T2 is a class type) can be
1211 implicitly converted to an lvalue of type "cv3 T3," where
1212 "cv1 T1" is reference-compatible with "cv3 T3". (this
1213 conversion is selected by enumerating the applicable
1214 conversion functions (_over.match.ref_) and choosing the
1215 best one through overload resolution. (_over.match_).
1217 the reference is bound to the lvalue result of the conversion
1218 in the second case. */
1219 conv = convert_class_to_reference (rto, from, expr);
1224 /* From this point on, we conceptually need temporaries, even if we
1225 elide them. Only the cases above are "direct bindings". */
1226 if (flags & LOOKUP_NO_TEMP_BIND)
1231 When a parameter of reference type is not bound directly to an
1232 argument expression, the conversion sequence is the one required
1233 to convert the argument expression to the underlying type of the
1234 reference according to _over.best.ics_. Conceptually, this
1235 conversion sequence corresponds to copy-initializing a temporary
1236 of the underlying type with the argument expression. Any
1237 difference in top-level cv-qualification is subsumed by the
1238 initialization itself and does not constitute a conversion. */
1242 Otherwise, the reference shall be to a non-volatile const type.
1244 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1245 if (!CP_TYPE_CONST_NON_VOLATILE_P (to) && !TYPE_REF_IS_RVALUE (rto))
1250 If the initializer expression is an rvalue, with T2 a class type,
1251 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1252 is bound in one of the following ways:
1254 -- The reference is bound to the object represented by the rvalue
1255 or to a sub-object within that object.
1259 We use the first alternative. The implicit conversion sequence
1260 is supposed to be same as we would obtain by generating a
1261 temporary. Fortunately, if the types are reference compatible,
1262 then this is either an identity conversion or the derived-to-base
1263 conversion, just as for direct binding. */
1264 if (CLASS_TYPE_P (from) && compatible_p)
1266 conv = build_identity_conv (from, expr);
1267 conv = direct_reference_binding (rto, conv);
1268 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1269 if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
1270 conv->u.next->check_copy_constructor_p = true;
1276 Otherwise, a temporary of type "cv1 T1" is created and
1277 initialized from the initializer expression using the rules for a
1278 non-reference copy initialization. If T1 is reference-related to
1279 T2, cv1 must be the same cv-qualification as, or greater
1280 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1281 if (related_p && !at_least_as_qualified_p (to, from))
1284 conv = implicit_conversion (to, from, expr, c_cast_p,
1289 conv = build_conv (ck_ref_bind, rto, conv);
1290 /* This reference binding, unlike those above, requires the
1291 creation of a temporary. */
1292 conv->need_temporary_p = true;
1293 conv->rvaluedness_matches_p = TYPE_REF_IS_RVALUE (rto);
1298 /* Returns the implicit conversion sequence (see [over.ics]) from type
1299 FROM to type TO. The optional expression EXPR may affect the
1300 conversion. FLAGS are the usual overloading flags. Only
1301 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1302 conversion is coming from a C-style cast. */
1305 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1310 if (from == error_mark_node || to == error_mark_node
1311 || expr == error_mark_node)
1314 if (TREE_CODE (to) == REFERENCE_TYPE)
1315 conv = reference_binding (to, from, expr, c_cast_p, flags);
1317 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1322 if (expr != NULL_TREE
1323 && (IS_AGGR_TYPE (from)
1324 || IS_AGGR_TYPE (to))
1325 && (flags & LOOKUP_NO_CONVERSION) == 0)
1327 struct z_candidate *cand;
1329 cand = build_user_type_conversion_1
1330 (to, expr, LOOKUP_ONLYCONVERTING);
1332 conv = cand->second_conv;
1334 /* We used to try to bind a reference to a temporary here, but that
1335 is now handled after the recursive call to this function at the end
1336 of reference_binding. */
1343 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1346 static struct z_candidate *
1347 add_candidate (struct z_candidate **candidates,
1349 size_t num_convs, conversion **convs,
1350 tree access_path, tree conversion_path,
1353 struct z_candidate *cand = (struct z_candidate *)
1354 conversion_obstack_alloc (sizeof (struct z_candidate));
1358 cand->convs = convs;
1359 cand->num_convs = num_convs;
1360 cand->access_path = access_path;
1361 cand->conversion_path = conversion_path;
1362 cand->viable = viable;
1363 cand->next = *candidates;
1369 /* Create an overload candidate for the function or method FN called with
1370 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1371 to implicit_conversion.
1373 CTYPE, if non-NULL, is the type we want to pretend this function
1374 comes from for purposes of overload resolution. */
1376 static struct z_candidate *
1377 add_function_candidate (struct z_candidate **candidates,
1378 tree fn, tree ctype, tree arglist,
1379 tree access_path, tree conversion_path,
1382 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1385 tree parmnode, argnode;
1389 /* At this point we should not see any functions which haven't been
1390 explicitly declared, except for friend functions which will have
1391 been found using argument dependent lookup. */
1392 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1394 /* The `this', `in_chrg' and VTT arguments to constructors are not
1395 considered in overload resolution. */
1396 if (DECL_CONSTRUCTOR_P (fn))
1398 parmlist = skip_artificial_parms_for (fn, parmlist);
1399 orig_arglist = arglist;
1400 arglist = skip_artificial_parms_for (fn, arglist);
1403 orig_arglist = arglist;
1405 len = list_length (arglist);
1406 convs = alloc_conversions (len);
1408 /* 13.3.2 - Viable functions [over.match.viable]
1409 First, to be a viable function, a candidate function shall have enough
1410 parameters to agree in number with the arguments in the list.
1412 We need to check this first; otherwise, checking the ICSes might cause
1413 us to produce an ill-formed template instantiation. */
1415 parmnode = parmlist;
1416 for (i = 0; i < len; ++i)
1418 if (parmnode == NULL_TREE || parmnode == void_list_node)
1420 parmnode = TREE_CHAIN (parmnode);
1423 if (i < len && parmnode)
1426 /* Make sure there are default args for the rest of the parms. */
1427 else if (!sufficient_parms_p (parmnode))
1433 /* Second, for F to be a viable function, there shall exist for each
1434 argument an implicit conversion sequence that converts that argument
1435 to the corresponding parameter of F. */
1437 parmnode = parmlist;
1440 for (i = 0; i < len; ++i)
1442 tree arg = TREE_VALUE (argnode);
1443 tree argtype = lvalue_type (arg);
1447 if (parmnode == void_list_node)
1450 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1451 && ! DECL_CONSTRUCTOR_P (fn));
1455 tree parmtype = TREE_VALUE (parmnode);
1457 /* The type of the implicit object parameter ('this') for
1458 overload resolution is not always the same as for the
1459 function itself; conversion functions are considered to
1460 be members of the class being converted, and functions
1461 introduced by a using-declaration are considered to be
1462 members of the class that uses them.
1464 Since build_over_call ignores the ICS for the `this'
1465 parameter, we can just change the parm type. */
1466 if (ctype && is_this)
1469 = build_qualified_type (ctype,
1470 TYPE_QUALS (TREE_TYPE (parmtype)));
1471 parmtype = build_pointer_type (parmtype);
1474 t = implicit_conversion (parmtype, argtype, arg,
1475 /*c_cast_p=*/false, flags);
1479 t = build_identity_conv (argtype, arg);
1480 t->ellipsis_p = true;
1497 parmnode = TREE_CHAIN (parmnode);
1498 argnode = TREE_CHAIN (argnode);
1502 return add_candidate (candidates, fn, orig_arglist, len, convs,
1503 access_path, conversion_path, viable);
1506 /* Create an overload candidate for the conversion function FN which will
1507 be invoked for expression OBJ, producing a pointer-to-function which
1508 will in turn be called with the argument list ARGLIST, and add it to
1509 CANDIDATES. FLAGS is passed on to implicit_conversion.
1511 Actually, we don't really care about FN; we care about the type it
1512 converts to. There may be multiple conversion functions that will
1513 convert to that type, and we rely on build_user_type_conversion_1 to
1514 choose the best one; so when we create our candidate, we record the type
1515 instead of the function. */
1517 static struct z_candidate *
1518 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1519 tree arglist, tree access_path, tree conversion_path)
1521 tree totype = TREE_TYPE (TREE_TYPE (fn));
1522 int i, len, viable, flags;
1523 tree parmlist, parmnode, argnode;
1526 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1527 parmlist = TREE_TYPE (parmlist);
1528 parmlist = TYPE_ARG_TYPES (parmlist);
1530 len = list_length (arglist) + 1;
1531 convs = alloc_conversions (len);
1532 parmnode = parmlist;
1535 flags = LOOKUP_NORMAL;
1537 /* Don't bother looking up the same type twice. */
1538 if (*candidates && (*candidates)->fn == totype)
1541 for (i = 0; i < len; ++i)
1543 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1544 tree argtype = lvalue_type (arg);
1548 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1550 else if (parmnode == void_list_node)
1553 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1554 /*c_cast_p=*/false, flags);
1557 t = build_identity_conv (argtype, arg);
1558 t->ellipsis_p = true;
1572 parmnode = TREE_CHAIN (parmnode);
1573 argnode = TREE_CHAIN (argnode);
1579 if (!sufficient_parms_p (parmnode))
1582 return add_candidate (candidates, totype, arglist, len, convs,
1583 access_path, conversion_path, viable);
1587 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1588 tree type1, tree type2, tree *args, tree *argtypes,
1600 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1601 convs = alloc_conversions (num_convs);
1603 for (i = 0; i < 2; ++i)
1608 t = implicit_conversion (types[i], argtypes[i], args[i],
1609 /*c_cast_p=*/false, flags);
1613 /* We need something for printing the candidate. */
1614 t = build_identity_conv (types[i], NULL_TREE);
1621 /* For COND_EXPR we rearranged the arguments; undo that now. */
1624 convs[2] = convs[1];
1625 convs[1] = convs[0];
1626 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1627 /*c_cast_p=*/false, flags);
1634 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1636 /*access_path=*/NULL_TREE,
1637 /*conversion_path=*/NULL_TREE,
1642 is_complete (tree t)
1644 return COMPLETE_TYPE_P (complete_type (t));
1647 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1650 promoted_arithmetic_type_p (tree type)
1654 In this section, the term promoted integral type is used to refer
1655 to those integral types which are preserved by integral promotion
1656 (including e.g. int and long but excluding e.g. char).
1657 Similarly, the term promoted arithmetic type refers to promoted
1658 integral types plus floating types. */
1659 return ((INTEGRAL_TYPE_P (type)
1660 && same_type_p (type_promotes_to (type), type))
1661 || TREE_CODE (type) == REAL_TYPE);
1664 /* Create any builtin operator overload candidates for the operator in
1665 question given the converted operand types TYPE1 and TYPE2. The other
1666 args are passed through from add_builtin_candidates to
1667 build_builtin_candidate.
1669 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1670 If CODE is requires candidates operands of the same type of the kind
1671 of which TYPE1 and TYPE2 are, we add both candidates
1672 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1675 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1676 enum tree_code code2, tree fnname, tree type1,
1677 tree type2, tree *args, tree *argtypes, int flags)
1681 case POSTINCREMENT_EXPR:
1682 case POSTDECREMENT_EXPR:
1683 args[1] = integer_zero_node;
1684 type2 = integer_type_node;
1693 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1694 and VQ is either volatile or empty, there exist candidate operator
1695 functions of the form
1696 VQ T& operator++(VQ T&);
1697 T operator++(VQ T&, int);
1698 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1699 type other than bool, and VQ is either volatile or empty, there exist
1700 candidate operator functions of the form
1701 VQ T& operator--(VQ T&);
1702 T operator--(VQ T&, int);
1703 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1704 complete object type, and VQ is either volatile or empty, there exist
1705 candidate operator functions of the form
1706 T*VQ& operator++(T*VQ&);
1707 T*VQ& operator--(T*VQ&);
1708 T* operator++(T*VQ&, int);
1709 T* operator--(T*VQ&, int); */
1711 case POSTDECREMENT_EXPR:
1712 case PREDECREMENT_EXPR:
1713 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1715 case POSTINCREMENT_EXPR:
1716 case PREINCREMENT_EXPR:
1717 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1719 type1 = build_reference_type (type1);
1724 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1725 exist candidate operator functions of the form
1729 8 For every function type T, there exist candidate operator functions of
1731 T& operator*(T*); */
1734 if (TREE_CODE (type1) == POINTER_TYPE
1735 && (TYPE_PTROB_P (type1)
1736 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1740 /* 9 For every type T, there exist candidate operator functions of the form
1743 10For every promoted arithmetic type T, there exist candidate operator
1744 functions of the form
1748 case UNARY_PLUS_EXPR: /* unary + */
1749 if (TREE_CODE (type1) == POINTER_TYPE)
1752 if (ARITHMETIC_TYPE_P (type1))
1756 /* 11For every promoted integral type T, there exist candidate operator
1757 functions of the form
1761 if (INTEGRAL_TYPE_P (type1))
1765 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1766 is the same type as C2 or is a derived class of C2, T is a complete
1767 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1768 there exist candidate operator functions of the form
1769 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1770 where CV12 is the union of CV1 and CV2. */
1773 if (TREE_CODE (type1) == POINTER_TYPE
1774 && TYPE_PTR_TO_MEMBER_P (type2))
1776 tree c1 = TREE_TYPE (type1);
1777 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1779 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1780 && (TYPE_PTRMEMFUNC_P (type2)
1781 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1786 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1787 didate operator functions of the form
1792 bool operator<(L, R);
1793 bool operator>(L, R);
1794 bool operator<=(L, R);
1795 bool operator>=(L, R);
1796 bool operator==(L, R);
1797 bool operator!=(L, R);
1798 where LR is the result of the usual arithmetic conversions between
1801 14For every pair of types T and I, where T is a cv-qualified or cv-
1802 unqualified complete object type and I is a promoted integral type,
1803 there exist candidate operator functions of the form
1804 T* operator+(T*, I);
1805 T& operator[](T*, I);
1806 T* operator-(T*, I);
1807 T* operator+(I, T*);
1808 T& operator[](I, T*);
1810 15For every T, where T is a pointer to complete object type, there exist
1811 candidate operator functions of the form112)
1812 ptrdiff_t operator-(T, T);
1814 16For every pointer or enumeration type T, there exist candidate operator
1815 functions of the form
1816 bool operator<(T, T);
1817 bool operator>(T, T);
1818 bool operator<=(T, T);
1819 bool operator>=(T, T);
1820 bool operator==(T, T);
1821 bool operator!=(T, T);
1823 17For every pointer to member type T, there exist candidate operator
1824 functions of the form
1825 bool operator==(T, T);
1826 bool operator!=(T, T); */
1829 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1831 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1833 type2 = ptrdiff_type_node;
1837 case TRUNC_DIV_EXPR:
1838 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1844 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1845 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1847 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1852 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1864 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1866 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1868 if (TREE_CODE (type1) == ENUMERAL_TYPE
1869 && TREE_CODE (type2) == ENUMERAL_TYPE)
1871 if (TYPE_PTR_P (type1)
1872 && null_ptr_cst_p (args[1])
1873 && !uses_template_parms (type1))
1878 if (null_ptr_cst_p (args[0])
1879 && TYPE_PTR_P (type2)
1880 && !uses_template_parms (type2))
1888 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1891 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1893 type1 = ptrdiff_type_node;
1896 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1898 type2 = ptrdiff_type_node;
1903 /* 18For every pair of promoted integral types L and R, there exist candi-
1904 date operator functions of the form
1911 where LR is the result of the usual arithmetic conversions between
1914 case TRUNC_MOD_EXPR:
1920 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1924 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1925 type, VQ is either volatile or empty, and R is a promoted arithmetic
1926 type, there exist candidate operator functions of the form
1927 VQ L& operator=(VQ L&, R);
1928 VQ L& operator*=(VQ L&, R);
1929 VQ L& operator/=(VQ L&, R);
1930 VQ L& operator+=(VQ L&, R);
1931 VQ L& operator-=(VQ L&, R);
1933 20For every pair T, VQ), where T is any type and VQ is either volatile
1934 or empty, there exist candidate operator functions of the form
1935 T*VQ& operator=(T*VQ&, T*);
1937 21For every pair T, VQ), where T is a pointer to member type and VQ is
1938 either volatile or empty, there exist candidate operator functions of
1940 VQ T& operator=(VQ T&, T);
1942 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1943 unqualified complete object type, VQ is either volatile or empty, and
1944 I is a promoted integral type, there exist candidate operator func-
1946 T*VQ& operator+=(T*VQ&, I);
1947 T*VQ& operator-=(T*VQ&, I);
1949 23For every triple L, VQ, R), where L is an integral or enumeration
1950 type, VQ is either volatile or empty, and R is a promoted integral
1951 type, there exist candidate operator functions of the form
1953 VQ L& operator%=(VQ L&, R);
1954 VQ L& operator<<=(VQ L&, R);
1955 VQ L& operator>>=(VQ L&, R);
1956 VQ L& operator&=(VQ L&, R);
1957 VQ L& operator^=(VQ L&, R);
1958 VQ L& operator|=(VQ L&, R); */
1965 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1967 type2 = ptrdiff_type_node;
1971 case TRUNC_DIV_EXPR:
1972 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1976 case TRUNC_MOD_EXPR:
1982 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1987 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1989 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1990 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1991 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1992 || ((TYPE_PTRMEMFUNC_P (type1)
1993 || TREE_CODE (type1) == POINTER_TYPE)
1994 && null_ptr_cst_p (args[1])))
2004 type1 = build_reference_type (type1);
2010 For every pair of promoted arithmetic types L and R, there
2011 exist candidate operator functions of the form
2013 LR operator?(bool, L, R);
2015 where LR is the result of the usual arithmetic conversions
2016 between types L and R.
2018 For every type T, where T is a pointer or pointer-to-member
2019 type, there exist candidate operator functions of the form T
2020 operator?(bool, T, T); */
2022 if (promoted_arithmetic_type_p (type1)
2023 && promoted_arithmetic_type_p (type2))
2027 /* Otherwise, the types should be pointers. */
2028 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
2029 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
2032 /* We don't check that the two types are the same; the logic
2033 below will actually create two candidates; one in which both
2034 parameter types are TYPE1, and one in which both parameter
2042 /* If we're dealing with two pointer types or two enumeral types,
2043 we need candidates for both of them. */
2044 if (type2 && !same_type_p (type1, type2)
2045 && TREE_CODE (type1) == TREE_CODE (type2)
2046 && (TREE_CODE (type1) == REFERENCE_TYPE
2047 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
2048 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
2049 || TYPE_PTRMEMFUNC_P (type1)
2050 || IS_AGGR_TYPE (type1)
2051 || TREE_CODE (type1) == ENUMERAL_TYPE))
2053 build_builtin_candidate
2054 (candidates, fnname, type1, type1, args, argtypes, flags);
2055 build_builtin_candidate
2056 (candidates, fnname, type2, type2, args, argtypes, flags);
2060 build_builtin_candidate
2061 (candidates, fnname, type1, type2, args, argtypes, flags);
2065 type_decays_to (tree type)
2067 if (TREE_CODE (type) == ARRAY_TYPE)
2068 return build_pointer_type (TREE_TYPE (type));
2069 if (TREE_CODE (type) == FUNCTION_TYPE)
2070 return build_pointer_type (type);
2074 /* There are three conditions of builtin candidates:
2076 1) bool-taking candidates. These are the same regardless of the input.
2077 2) pointer-pair taking candidates. These are generated for each type
2078 one of the input types converts to.
2079 3) arithmetic candidates. According to the standard, we should generate
2080 all of these, but I'm trying not to...
2082 Here we generate a superset of the possible candidates for this particular
2083 case. That is a subset of the full set the standard defines, plus some
2084 other cases which the standard disallows. add_builtin_candidate will
2085 filter out the invalid set. */
2088 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2089 enum tree_code code2, tree fnname, tree *args,
2094 tree type, argtypes[3];
2095 /* TYPES[i] is the set of possible builtin-operator parameter types
2096 we will consider for the Ith argument. These are represented as
2097 a TREE_LIST; the TREE_VALUE of each node is the potential
2101 for (i = 0; i < 3; ++i)
2104 argtypes[i] = lvalue_type (args[i]);
2106 argtypes[i] = NULL_TREE;
2111 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2112 and VQ is either volatile or empty, there exist candidate operator
2113 functions of the form
2114 VQ T& operator++(VQ T&); */
2116 case POSTINCREMENT_EXPR:
2117 case PREINCREMENT_EXPR:
2118 case POSTDECREMENT_EXPR:
2119 case PREDECREMENT_EXPR:
2124 /* 24There also exist candidate operator functions of the form
2125 bool operator!(bool);
2126 bool operator&&(bool, bool);
2127 bool operator||(bool, bool); */
2129 case TRUTH_NOT_EXPR:
2130 build_builtin_candidate
2131 (candidates, fnname, boolean_type_node,
2132 NULL_TREE, args, argtypes, flags);
2135 case TRUTH_ORIF_EXPR:
2136 case TRUTH_ANDIF_EXPR:
2137 build_builtin_candidate
2138 (candidates, fnname, boolean_type_node,
2139 boolean_type_node, args, argtypes, flags);
2161 types[0] = types[1] = NULL_TREE;
2163 for (i = 0; i < 2; ++i)
2167 else if (IS_AGGR_TYPE (argtypes[i]))
2171 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2174 convs = lookup_conversions (argtypes[i]);
2176 if (code == COND_EXPR)
2178 if (real_lvalue_p (args[i]))
2179 types[i] = tree_cons
2180 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2182 types[i] = tree_cons
2183 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2189 for (; convs; convs = TREE_CHAIN (convs))
2191 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2194 && (TREE_CODE (type) != REFERENCE_TYPE
2195 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2198 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2199 types[i] = tree_cons (NULL_TREE, type, types[i]);
2201 type = non_reference (type);
2202 if (i != 0 || ! ref1)
2204 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2205 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2206 types[i] = tree_cons (NULL_TREE, type, types[i]);
2207 if (INTEGRAL_TYPE_P (type))
2208 type = type_promotes_to (type);
2211 if (! value_member (type, types[i]))
2212 types[i] = tree_cons (NULL_TREE, type, types[i]);
2217 if (code == COND_EXPR && real_lvalue_p (args[i]))
2218 types[i] = tree_cons
2219 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2220 type = non_reference (argtypes[i]);
2221 if (i != 0 || ! ref1)
2223 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2224 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2225 types[i] = tree_cons (NULL_TREE, type, types[i]);
2226 if (INTEGRAL_TYPE_P (type))
2227 type = type_promotes_to (type);
2229 types[i] = tree_cons (NULL_TREE, type, types[i]);
2233 /* Run through the possible parameter types of both arguments,
2234 creating candidates with those parameter types. */
2235 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2238 for (type = types[1]; type; type = TREE_CHAIN (type))
2239 add_builtin_candidate
2240 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2241 TREE_VALUE (type), args, argtypes, flags);
2243 add_builtin_candidate
2244 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2245 NULL_TREE, args, argtypes, flags);
2250 /* If TMPL can be successfully instantiated as indicated by
2251 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2253 TMPL is the template. EXPLICIT_TARGS are any explicit template
2254 arguments. ARGLIST is the arguments provided at the call-site.
2255 The RETURN_TYPE is the desired type for conversion operators. If
2256 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2257 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2258 add_conv_candidate. */
2260 static struct z_candidate*
2261 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2262 tree ctype, tree explicit_targs, tree arglist,
2263 tree return_type, tree access_path,
2264 tree conversion_path, int flags, tree obj,
2265 unification_kind_t strict)
2267 int ntparms = DECL_NTPARMS (tmpl);
2268 tree targs = make_tree_vec (ntparms);
2269 tree args_without_in_chrg = arglist;
2270 struct z_candidate *cand;
2274 /* We don't do deduction on the in-charge parameter, the VTT
2275 parameter or 'this'. */
2276 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2277 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2279 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2280 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2281 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2282 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2284 i = fn_type_unification (tmpl, explicit_targs, targs,
2285 args_without_in_chrg,
2286 return_type, strict, flags);
2291 fn = instantiate_template (tmpl, targs, tf_none);
2292 if (fn == error_mark_node)
2297 A member function template is never instantiated to perform the
2298 copy of a class object to an object of its class type.
2300 It's a little unclear what this means; the standard explicitly
2301 does allow a template to be used to copy a class. For example,
2306 template <class T> A(const T&);
2309 void g () { A a (f ()); }
2311 the member template will be used to make the copy. The section
2312 quoted above appears in the paragraph that forbids constructors
2313 whose only parameter is (a possibly cv-qualified variant of) the
2314 class type, and a logical interpretation is that the intent was
2315 to forbid the instantiation of member templates which would then
2317 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2319 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2320 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2325 if (obj != NULL_TREE)
2326 /* Aha, this is a conversion function. */
2327 cand = add_conv_candidate (candidates, fn, obj, access_path,
2328 conversion_path, arglist);
2330 cand = add_function_candidate (candidates, fn, ctype,
2331 arglist, access_path,
2332 conversion_path, flags);
2333 if (DECL_TI_TEMPLATE (fn) != tmpl)
2334 /* This situation can occur if a member template of a template
2335 class is specialized. Then, instantiate_template might return
2336 an instantiation of the specialization, in which case the
2337 DECL_TI_TEMPLATE field will point at the original
2338 specialization. For example:
2340 template <class T> struct S { template <class U> void f(U);
2341 template <> void f(int) {}; };
2345 Here, TMPL will be template <class U> S<double>::f(U).
2346 And, instantiate template will give us the specialization
2347 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2348 for this will point at template <class T> template <> S<T>::f(int),
2349 so that we can find the definition. For the purposes of
2350 overload resolution, however, we want the original TMPL. */
2351 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2353 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2359 static struct z_candidate *
2360 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2361 tree explicit_targs, tree arglist, tree return_type,
2362 tree access_path, tree conversion_path, int flags,
2363 unification_kind_t strict)
2366 add_template_candidate_real (candidates, tmpl, ctype,
2367 explicit_targs, arglist, return_type,
2368 access_path, conversion_path,
2369 flags, NULL_TREE, strict);
2373 static struct z_candidate *
2374 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2375 tree obj, tree arglist, tree return_type,
2376 tree access_path, tree conversion_path)
2379 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2380 arglist, return_type, access_path,
2381 conversion_path, 0, obj, DEDUCE_CONV);
2384 /* The CANDS are the set of candidates that were considered for
2385 overload resolution. Return the set of viable candidates. If none
2386 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2387 is true if a candidate should be considered viable only if it is
2390 static struct z_candidate*
2391 splice_viable (struct z_candidate *cands,
2395 struct z_candidate *viable;
2396 struct z_candidate **last_viable;
2397 struct z_candidate **cand;
2400 last_viable = &viable;
2401 *any_viable_p = false;
2406 struct z_candidate *c = *cand;
2407 if (strict_p ? c->viable == 1 : c->viable)
2412 last_viable = &c->next;
2413 *any_viable_p = true;
2419 return viable ? viable : cands;
2423 any_strictly_viable (struct z_candidate *cands)
2425 for (; cands; cands = cands->next)
2426 if (cands->viable == 1)
2431 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2432 words, it is about to become the "this" pointer for a member
2433 function call. Take the address of the object. */
2436 build_this (tree obj)
2438 /* In a template, we are only concerned about the type of the
2439 expression, so we can take a shortcut. */
2440 if (processing_template_decl)
2441 return build_address (obj);
2443 return build_unary_op (ADDR_EXPR, obj, 0);
2446 /* Returns true iff functions are equivalent. Equivalent functions are
2447 not '==' only if one is a function-local extern function or if
2448 both are extern "C". */
2451 equal_functions (tree fn1, tree fn2)
2453 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2454 || DECL_EXTERN_C_FUNCTION_P (fn1))
2455 return decls_match (fn1, fn2);
2459 /* Print information about one overload candidate CANDIDATE. MSGSTR
2460 is the text to print before the candidate itself.
2462 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2463 to have been run through gettext by the caller. This wart makes
2464 life simpler in print_z_candidates and for the translators. */
2467 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2469 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2471 if (candidate->num_convs == 3)
2472 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2473 candidate->convs[0]->type,
2474 candidate->convs[1]->type,
2475 candidate->convs[2]->type);
2476 else if (candidate->num_convs == 2)
2477 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2478 candidate->convs[0]->type,
2479 candidate->convs[1]->type);
2481 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2482 candidate->convs[0]->type);
2484 else if (TYPE_P (candidate->fn))
2485 inform ("%s %T <conversion>", msgstr, candidate->fn);
2486 else if (candidate->viable == -1)
2487 inform ("%s %+#D <near match>", msgstr, candidate->fn);
2489 inform ("%s %+#D", msgstr, candidate->fn);
2493 print_z_candidates (struct z_candidate *candidates)
2496 struct z_candidate *cand1;
2497 struct z_candidate **cand2;
2499 /* There may be duplicates in the set of candidates. We put off
2500 checking this condition as long as possible, since we have no way
2501 to eliminate duplicates from a set of functions in less than n^2
2502 time. Now we are about to emit an error message, so it is more
2503 permissible to go slowly. */
2504 for (cand1 = candidates; cand1; cand1 = cand1->next)
2506 tree fn = cand1->fn;
2507 /* Skip builtin candidates and conversion functions. */
2508 if (TREE_CODE (fn) != FUNCTION_DECL)
2510 cand2 = &cand1->next;
2513 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2514 && equal_functions (fn, (*cand2)->fn))
2515 *cand2 = (*cand2)->next;
2517 cand2 = &(*cand2)->next;
2524 str = _("candidates are:");
2525 print_z_candidate (str, candidates);
2526 if (candidates->next)
2528 /* Indent successive candidates by the width of the translation
2529 of the above string. */
2530 size_t len = gcc_gettext_width (str) + 1;
2531 char *spaces = (char *) alloca (len);
2532 memset (spaces, ' ', len-1);
2533 spaces[len - 1] = '\0';
2535 candidates = candidates->next;
2538 print_z_candidate (spaces, candidates);
2539 candidates = candidates->next;
2545 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2546 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2547 the result of the conversion function to convert it to the final
2548 desired type. Merge the two sequences into a single sequence,
2549 and return the merged sequence. */
2552 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2556 gcc_assert (user_seq->kind == ck_user);
2558 /* Find the end of the second conversion sequence. */
2560 while ((*t)->kind != ck_identity)
2561 t = &((*t)->u.next);
2563 /* Replace the identity conversion with the user conversion
2567 /* The entire sequence is a user-conversion sequence. */
2568 std_seq->user_conv_p = true;
2573 /* Returns the best overload candidate to perform the requested
2574 conversion. This function is used for three the overloading situations
2575 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2576 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2577 per [dcl.init.ref], so we ignore temporary bindings. */
2579 static struct z_candidate *
2580 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2582 struct z_candidate *candidates, *cand;
2583 tree fromtype = TREE_TYPE (expr);
2584 tree ctors = NULL_TREE;
2585 tree conv_fns = NULL_TREE;
2586 conversion *conv = NULL;
2587 tree args = NULL_TREE;
2590 /* We represent conversion within a hierarchy using RVALUE_CONV and
2591 BASE_CONV, as specified by [over.best.ics]; these become plain
2592 constructor calls, as specified in [dcl.init]. */
2593 gcc_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2594 || !DERIVED_FROM_P (totype, fromtype));
2596 if (IS_AGGR_TYPE (totype))
2597 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2599 if (IS_AGGR_TYPE (fromtype))
2600 conv_fns = lookup_conversions (fromtype);
2603 flags |= LOOKUP_NO_CONVERSION;
2609 ctors = BASELINK_FUNCTIONS (ctors);
2611 t = build_int_cst (build_pointer_type (totype), 0);
2612 args = build_tree_list (NULL_TREE, expr);
2613 /* We should never try to call the abstract or base constructor
2615 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2616 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2617 args = tree_cons (NULL_TREE, t, args);
2619 for (; ctors; ctors = OVL_NEXT (ctors))
2621 tree ctor = OVL_CURRENT (ctors);
2622 if (DECL_NONCONVERTING_P (ctor))
2625 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2626 cand = add_template_candidate (&candidates, ctor, totype,
2627 NULL_TREE, args, NULL_TREE,
2628 TYPE_BINFO (totype),
2629 TYPE_BINFO (totype),
2633 cand = add_function_candidate (&candidates, ctor, totype,
2634 args, TYPE_BINFO (totype),
2635 TYPE_BINFO (totype),
2639 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2643 args = build_tree_list (NULL_TREE, build_this (expr));
2645 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2648 tree conversion_path = TREE_PURPOSE (conv_fns);
2649 int convflags = LOOKUP_NO_CONVERSION;
2651 /* If we are called to convert to a reference type, we are trying to
2652 find an lvalue binding, so don't even consider temporaries. If
2653 we don't find an lvalue binding, the caller will try again to
2654 look for a temporary binding. */
2655 if (TREE_CODE (totype) == REFERENCE_TYPE)
2656 convflags |= LOOKUP_NO_TEMP_BIND;
2658 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2660 tree fn = OVL_CURRENT (fns);
2662 /* [over.match.funcs] For conversion functions, the function
2663 is considered to be a member of the class of the implicit
2664 object argument for the purpose of defining the type of
2665 the implicit object parameter.
2667 So we pass fromtype as CTYPE to add_*_candidate. */
2669 if (TREE_CODE (fn) == TEMPLATE_DECL)
2670 cand = add_template_candidate (&candidates, fn, fromtype,
2673 TYPE_BINFO (fromtype),
2678 cand = add_function_candidate (&candidates, fn, fromtype,
2680 TYPE_BINFO (fromtype),
2687 = implicit_conversion (totype,
2688 TREE_TYPE (TREE_TYPE (cand->fn)),
2690 /*c_cast_p=*/false, convflags);
2692 cand->second_conv = ics;
2696 else if (candidates->viable == 1 && ics->bad_p)
2702 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2706 cand = tourney (candidates);
2709 if (flags & LOOKUP_COMPLAIN)
2711 error ("conversion from %qT to %qT is ambiguous",
2713 print_z_candidates (candidates);
2716 cand = candidates; /* any one will do */
2717 cand->second_conv = build_ambiguous_conv (totype, expr);
2718 cand->second_conv->user_conv_p = true;
2719 if (!any_strictly_viable (candidates))
2720 cand->second_conv->bad_p = true;
2721 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2722 ambiguous conversion is no worse than another user-defined
2728 /* Build the user conversion sequence. */
2731 (DECL_CONSTRUCTOR_P (cand->fn)
2732 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2733 build_identity_conv (TREE_TYPE (expr), expr));
2736 /* Combine it with the second conversion sequence. */
2737 cand->second_conv = merge_conversion_sequences (conv,
2740 if (cand->viable == -1)
2741 cand->second_conv->bad_p = true;
2747 build_user_type_conversion (tree totype, tree expr, int flags)
2749 struct z_candidate *cand
2750 = build_user_type_conversion_1 (totype, expr, flags);
2754 if (cand->second_conv->kind == ck_ambig)
2755 return error_mark_node;
2756 expr = convert_like (cand->second_conv, expr);
2757 return convert_from_reference (expr);
2762 /* Do any initial processing on the arguments to a function call. */
2765 resolve_args (tree args)
2768 for (t = args; t; t = TREE_CHAIN (t))
2770 tree arg = TREE_VALUE (t);
2772 if (error_operand_p (arg))
2773 return error_mark_node;
2774 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2776 error ("invalid use of void expression");
2777 return error_mark_node;
2779 else if (invalid_nonstatic_memfn_p (arg))
2780 return error_mark_node;
2785 /* Perform overload resolution on FN, which is called with the ARGS.
2787 Return the candidate function selected by overload resolution, or
2788 NULL if the event that overload resolution failed. In the case
2789 that overload resolution fails, *CANDIDATES will be the set of
2790 candidates considered, and ANY_VIABLE_P will be set to true or
2791 false to indicate whether or not any of the candidates were
2794 The ARGS should already have gone through RESOLVE_ARGS before this
2795 function is called. */
2797 static struct z_candidate *
2798 perform_overload_resolution (tree fn,
2800 struct z_candidate **candidates,
2803 struct z_candidate *cand;
2804 tree explicit_targs = NULL_TREE;
2805 int template_only = 0;
2808 *any_viable_p = true;
2810 /* Check FN and ARGS. */
2811 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2812 || TREE_CODE (fn) == TEMPLATE_DECL
2813 || TREE_CODE (fn) == OVERLOAD
2814 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2815 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2817 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2819 explicit_targs = TREE_OPERAND (fn, 1);
2820 fn = TREE_OPERAND (fn, 0);
2824 /* Add the various candidate functions. */
2825 add_candidates (fn, args, explicit_targs, template_only,
2826 /*conversion_path=*/NULL_TREE,
2827 /*access_path=*/NULL_TREE,
2831 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2835 cand = tourney (*candidates);
2839 /* Return an expression for a call to FN (a namespace-scope function,
2840 or a static member function) with the ARGS. */
2843 build_new_function_call (tree fn, tree args, bool koenig_p)
2845 struct z_candidate *candidates, *cand;
2850 args = resolve_args (args);
2851 if (args == error_mark_node)
2852 return error_mark_node;
2854 /* If this function was found without using argument dependent
2855 lookup, then we want to ignore any undeclared friend
2861 fn = remove_hidden_names (fn);
2864 error ("no matching function for call to %<%D(%A)%>",
2865 DECL_NAME (OVL_CURRENT (orig_fn)), args);
2866 return error_mark_node;
2870 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2871 p = conversion_obstack_alloc (0);
2873 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2877 if (!any_viable_p && candidates && ! candidates->next)
2878 return build_function_call (candidates->fn, args);
2879 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2880 fn = TREE_OPERAND (fn, 0);
2882 error ("no matching function for call to %<%D(%A)%>",
2883 DECL_NAME (OVL_CURRENT (fn)), args);
2885 error ("call of overloaded %<%D(%A)%> is ambiguous",
2886 DECL_NAME (OVL_CURRENT (fn)), args);
2888 print_z_candidates (candidates);
2889 result = error_mark_node;
2892 result = build_over_call (cand, LOOKUP_NORMAL);
2894 /* Free all the conversions we allocated. */
2895 obstack_free (&conversion_obstack, p);
2900 /* Build a call to a global operator new. FNNAME is the name of the
2901 operator (either "operator new" or "operator new[]") and ARGS are
2902 the arguments provided. *SIZE points to the total number of bytes
2903 required by the allocation, and is updated if that is changed here.
2904 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2905 function determines that no cookie should be used, after all,
2906 *COOKIE_SIZE is set to NULL_TREE. If FN is non-NULL, it will be
2907 set, upon return, to the allocation function called. */
2910 build_operator_new_call (tree fnname, tree args,
2911 tree *size, tree *cookie_size,
2915 struct z_candidate *candidates;
2916 struct z_candidate *cand;
2921 args = tree_cons (NULL_TREE, *size, args);
2922 args = resolve_args (args);
2923 if (args == error_mark_node)
2930 If this lookup fails to find the name, or if the allocated type
2931 is not a class type, the allocation function's name is looked
2932 up in the global scope.
2934 we disregard block-scope declarations of "operator new". */
2935 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
2937 /* Figure out what function is being called. */
2938 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2940 /* If no suitable function could be found, issue an error message
2945 error ("no matching function for call to %<%D(%A)%>",
2946 DECL_NAME (OVL_CURRENT (fns)), args);
2948 error ("call of overloaded %<%D(%A)%> is ambiguous",
2949 DECL_NAME (OVL_CURRENT (fns)), args);
2951 print_z_candidates (candidates);
2952 return error_mark_node;
2955 /* If a cookie is required, add some extra space. Whether
2956 or not a cookie is required cannot be determined until
2957 after we know which function was called. */
2960 bool use_cookie = true;
2961 if (!abi_version_at_least (2))
2963 tree placement = TREE_CHAIN (args);
2964 /* In G++ 3.2, the check was implemented incorrectly; it
2965 looked at the placement expression, rather than the
2966 type of the function. */
2967 if (placement && !TREE_CHAIN (placement)
2968 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2976 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2977 /* Skip the size_t parameter. */
2978 arg_types = TREE_CHAIN (arg_types);
2979 /* Check the remaining parameters (if any). */
2981 && TREE_CHAIN (arg_types) == void_list_node
2982 && same_type_p (TREE_VALUE (arg_types),
2986 /* If we need a cookie, adjust the number of bytes allocated. */
2989 /* Update the total size. */
2990 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2991 /* Update the argument list to reflect the adjusted size. */
2992 TREE_VALUE (args) = *size;
2995 *cookie_size = NULL_TREE;
2998 /* Tell our caller which function we decided to call. */
3002 /* Build the CALL_EXPR. */
3003 return build_over_call (cand, LOOKUP_NORMAL);
3007 build_object_call (tree obj, tree args)
3009 struct z_candidate *candidates = 0, *cand;
3010 tree fns, convs, mem_args = NULL_TREE;
3011 tree type = TREE_TYPE (obj);
3013 tree result = NULL_TREE;
3016 if (TYPE_PTRMEMFUNC_P (type))
3018 /* It's no good looking for an overloaded operator() on a
3019 pointer-to-member-function. */
3020 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3021 return error_mark_node;
3024 if (TYPE_BINFO (type))
3026 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
3027 if (fns == error_mark_node)
3028 return error_mark_node;
3033 args = resolve_args (args);
3035 if (args == error_mark_node)
3036 return error_mark_node;
3038 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3039 p = conversion_obstack_alloc (0);
3043 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
3044 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
3046 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
3048 tree fn = OVL_CURRENT (fns);
3049 if (TREE_CODE (fn) == TEMPLATE_DECL)
3050 add_template_candidate (&candidates, fn, base, NULL_TREE,
3051 mem_args, NULL_TREE,
3054 LOOKUP_NORMAL, DEDUCE_CALL);
3056 add_function_candidate
3057 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
3058 TYPE_BINFO (type), LOOKUP_NORMAL);
3062 convs = lookup_conversions (type);
3064 for (; convs; convs = TREE_CHAIN (convs))
3066 tree fns = TREE_VALUE (convs);
3067 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
3069 if ((TREE_CODE (totype) == POINTER_TYPE
3070 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3071 || (TREE_CODE (totype) == REFERENCE_TYPE
3072 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
3073 || (TREE_CODE (totype) == REFERENCE_TYPE
3074 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
3075 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
3076 for (; fns; fns = OVL_NEXT (fns))
3078 tree fn = OVL_CURRENT (fns);
3079 if (TREE_CODE (fn) == TEMPLATE_DECL)
3080 add_template_conv_candidate
3081 (&candidates, fn, obj, args, totype,
3082 /*access_path=*/NULL_TREE,
3083 /*conversion_path=*/NULL_TREE);
3085 add_conv_candidate (&candidates, fn, obj, args,
3086 /*conversion_path=*/NULL_TREE,
3087 /*access_path=*/NULL_TREE);
3091 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3094 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3095 print_z_candidates (candidates);
3096 result = error_mark_node;
3100 cand = tourney (candidates);
3103 error ("call of %<(%T) (%A)%> is ambiguous", TREE_TYPE (obj), args);
3104 print_z_candidates (candidates);
3105 result = error_mark_node;
3107 /* Since cand->fn will be a type, not a function, for a conversion
3108 function, we must be careful not to unconditionally look at
3110 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3111 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3112 result = build_over_call (cand, LOOKUP_NORMAL);
3115 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1);
3116 obj = convert_from_reference (obj);
3117 result = build_function_call (obj, args);
3121 /* Free all the conversions we allocated. */
3122 obstack_free (&conversion_obstack, p);
3128 op_error (enum tree_code code, enum tree_code code2,
3129 tree arg1, tree arg2, tree arg3, const char *problem)
3133 if (code == MODIFY_EXPR)
3134 opname = assignment_operator_name_info[code2].name;
3136 opname = operator_name_info[code].name;
3141 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3142 problem, arg1, arg2, arg3);
3145 case POSTINCREMENT_EXPR:
3146 case POSTDECREMENT_EXPR:
3147 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3151 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3156 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3161 error ("%s for %<operator%s%> in %<%E %s %E%>",
3162 problem, opname, arg1, opname, arg2);
3164 error ("%s for %<operator%s%> in %<%s%E%>",
3165 problem, opname, opname, arg1);
3170 /* Return the implicit conversion sequence that could be used to
3171 convert E1 to E2 in [expr.cond]. */
3174 conditional_conversion (tree e1, tree e2)
3176 tree t1 = non_reference (TREE_TYPE (e1));
3177 tree t2 = non_reference (TREE_TYPE (e2));
3183 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3184 implicitly converted (clause _conv_) to the type "reference to
3185 T2", subject to the constraint that in the conversion the
3186 reference must bind directly (_dcl.init.ref_) to E1. */
3187 if (real_lvalue_p (e2))
3189 conv = implicit_conversion (build_reference_type (t2),
3193 LOOKUP_NO_TEMP_BIND);
3200 If E1 and E2 have class type, and the underlying class types are
3201 the same or one is a base class of the other: E1 can be converted
3202 to match E2 if the class of T2 is the same type as, or a base
3203 class of, the class of T1, and the cv-qualification of T2 is the
3204 same cv-qualification as, or a greater cv-qualification than, the
3205 cv-qualification of T1. If the conversion is applied, E1 is
3206 changed to an rvalue of type T2 that still refers to the original
3207 source class object (or the appropriate subobject thereof). */
3208 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3209 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3211 if (good_base && at_least_as_qualified_p (t2, t1))
3213 conv = build_identity_conv (t1, e1);
3214 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3215 TYPE_MAIN_VARIANT (t2)))
3216 conv = build_conv (ck_base, t2, conv);
3218 conv = build_conv (ck_rvalue, t2, conv);
3227 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3228 converted to the type that expression E2 would have if E2 were
3229 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3230 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3234 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3235 arguments to the conditional expression. */
3238 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3242 tree result = NULL_TREE;
3243 tree result_type = NULL_TREE;
3244 bool lvalue_p = true;
3245 struct z_candidate *candidates = 0;
3246 struct z_candidate *cand;
3249 /* As a G++ extension, the second argument to the conditional can be
3250 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3251 c'.) If the second operand is omitted, make sure it is
3252 calculated only once. */
3256 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3258 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3259 if (real_lvalue_p (arg1))
3260 arg2 = arg1 = stabilize_reference (arg1);
3262 arg2 = arg1 = save_expr (arg1);
3267 The first expr ession is implicitly converted to bool (clause
3269 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3271 /* If something has already gone wrong, just pass that fact up the
3273 if (error_operand_p (arg1)
3274 || error_operand_p (arg2)
3275 || error_operand_p (arg3))
3276 return error_mark_node;
3280 If either the second or the third operand has type (possibly
3281 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3282 array-to-pointer (_conv.array_), and function-to-pointer
3283 (_conv.func_) standard conversions are performed on the second
3284 and third operands. */
3285 arg2_type = unlowered_expr_type (arg2);
3286 arg3_type = unlowered_expr_type (arg3);
3287 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3289 /* Do the conversions. We don't these for `void' type arguments
3290 since it can't have any effect and since decay_conversion
3291 does not handle that case gracefully. */
3292 if (!VOID_TYPE_P (arg2_type))
3293 arg2 = decay_conversion (arg2);
3294 if (!VOID_TYPE_P (arg3_type))
3295 arg3 = decay_conversion (arg3);
3296 arg2_type = TREE_TYPE (arg2);
3297 arg3_type = TREE_TYPE (arg3);
3301 One of the following shall hold:
3303 --The second or the third operand (but not both) is a
3304 throw-expression (_except.throw_); the result is of the
3305 type of the other and is an rvalue.
3307 --Both the second and the third operands have type void; the
3308 result is of type void and is an rvalue.
3310 We must avoid calling force_rvalue for expressions of type
3311 "void" because it will complain that their value is being
3313 if (TREE_CODE (arg2) == THROW_EXPR
3314 && TREE_CODE (arg3) != THROW_EXPR)
3316 if (!VOID_TYPE_P (arg3_type))
3317 arg3 = force_rvalue (arg3);
3318 arg3_type = TREE_TYPE (arg3);
3319 result_type = arg3_type;
3321 else if (TREE_CODE (arg2) != THROW_EXPR
3322 && TREE_CODE (arg3) == THROW_EXPR)
3324 if (!VOID_TYPE_P (arg2_type))
3325 arg2 = force_rvalue (arg2);
3326 arg2_type = TREE_TYPE (arg2);
3327 result_type = arg2_type;
3329 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3330 result_type = void_type_node;
3333 if (VOID_TYPE_P (arg2_type))
3334 error ("second operand to the conditional operator "
3335 "is of type %<void%>, "
3336 "but the third operand is neither a throw-expression "
3337 "nor of type %<void%>");
3339 error ("third operand to the conditional operator "
3340 "is of type %<void%>, "
3341 "but the second operand is neither a throw-expression "
3342 "nor of type %<void%>");
3343 return error_mark_node;
3347 goto valid_operands;
3351 Otherwise, if the second and third operand have different types,
3352 and either has (possibly cv-qualified) class type, an attempt is
3353 made to convert each of those operands to the type of the other. */
3354 else if (!same_type_p (arg2_type, arg3_type)
3355 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3360 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3361 p = conversion_obstack_alloc (0);
3363 conv2 = conditional_conversion (arg2, arg3);
3364 conv3 = conditional_conversion (arg3, arg2);
3368 If both can be converted, or one can be converted but the
3369 conversion is ambiguous, the program is ill-formed. If
3370 neither can be converted, the operands are left unchanged and
3371 further checking is performed as described below. If exactly
3372 one conversion is possible, that conversion is applied to the
3373 chosen operand and the converted operand is used in place of
3374 the original operand for the remainder of this section. */
3375 if ((conv2 && !conv2->bad_p
3376 && conv3 && !conv3->bad_p)
3377 || (conv2 && conv2->kind == ck_ambig)
3378 || (conv3 && conv3->kind == ck_ambig))
3380 error ("operands to ?: have different types %qT and %qT",
3381 arg2_type, arg3_type);
3382 result = error_mark_node;
3384 else if (conv2 && (!conv2->bad_p || !conv3))
3386 arg2 = convert_like (conv2, arg2);
3387 arg2 = convert_from_reference (arg2);
3388 arg2_type = TREE_TYPE (arg2);
3389 /* Even if CONV2 is a valid conversion, the result of the
3390 conversion may be invalid. For example, if ARG3 has type
3391 "volatile X", and X does not have a copy constructor
3392 accepting a "volatile X&", then even if ARG2 can be
3393 converted to X, the conversion will fail. */
3394 if (error_operand_p (arg2))
3395 result = error_mark_node;
3397 else if (conv3 && (!conv3->bad_p || !conv2))
3399 arg3 = convert_like (conv3, arg3);
3400 arg3 = convert_from_reference (arg3);
3401 arg3_type = TREE_TYPE (arg3);
3402 if (error_operand_p (arg3))
3403 result = error_mark_node;
3406 /* Free all the conversions we allocated. */
3407 obstack_free (&conversion_obstack, p);
3412 /* If, after the conversion, both operands have class type,
3413 treat the cv-qualification of both operands as if it were the
3414 union of the cv-qualification of the operands.
3416 The standard is not clear about what to do in this
3417 circumstance. For example, if the first operand has type
3418 "const X" and the second operand has a user-defined
3419 conversion to "volatile X", what is the type of the second
3420 operand after this step? Making it be "const X" (matching
3421 the first operand) seems wrong, as that discards the
3422 qualification without actually performing a copy. Leaving it
3423 as "volatile X" seems wrong as that will result in the
3424 conditional expression failing altogether, even though,
3425 according to this step, the one operand could be converted to
3426 the type of the other. */
3427 if ((conv2 || conv3)
3428 && CLASS_TYPE_P (arg2_type)
3429 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3430 arg2_type = arg3_type =
3431 cp_build_qualified_type (arg2_type,
3432 TYPE_QUALS (arg2_type)
3433 | TYPE_QUALS (arg3_type));
3438 If the second and third operands are lvalues and have the same
3439 type, the result is of that type and is an lvalue. */
3440 if (real_lvalue_p (arg2)
3441 && real_lvalue_p (arg3)
3442 && same_type_p (arg2_type, arg3_type))
3444 result_type = arg2_type;
3445 goto valid_operands;
3450 Otherwise, the result is an rvalue. If the second and third
3451 operand do not have the same type, and either has (possibly
3452 cv-qualified) class type, overload resolution is used to
3453 determine the conversions (if any) to be applied to the operands
3454 (_over.match.oper_, _over.built_). */
3456 if (!same_type_p (arg2_type, arg3_type)
3457 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3463 /* Rearrange the arguments so that add_builtin_candidate only has
3464 to know about two args. In build_builtin_candidates, the
3465 arguments are unscrambled. */
3469 add_builtin_candidates (&candidates,
3472 ansi_opname (COND_EXPR),
3478 If the overload resolution fails, the program is
3480 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3483 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3484 print_z_candidates (candidates);
3485 return error_mark_node;
3487 cand = tourney (candidates);
3490 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3491 print_z_candidates (candidates);
3492 return error_mark_node;
3497 Otherwise, the conversions thus determined are applied, and
3498 the converted operands are used in place of the original
3499 operands for the remainder of this section. */
3500 conv = cand->convs[0];
3501 arg1 = convert_like (conv, arg1);
3502 conv = cand->convs[1];
3503 arg2 = convert_like (conv, arg2);
3504 conv = cand->convs[2];
3505 arg3 = convert_like (conv, arg3);
3510 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3511 and function-to-pointer (_conv.func_) standard conversions are
3512 performed on the second and third operands.
3514 We need to force the lvalue-to-rvalue conversion here for class types,
3515 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3516 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3519 arg2 = force_rvalue (arg2);
3520 if (!CLASS_TYPE_P (arg2_type))
3521 arg2_type = TREE_TYPE (arg2);
3523 arg3 = force_rvalue (arg3);
3524 if (!CLASS_TYPE_P (arg2_type))
3525 arg3_type = TREE_TYPE (arg3);
3527 if (arg2 == error_mark_node || arg3 == error_mark_node)
3528 return error_mark_node;
3532 After those conversions, one of the following shall hold:
3534 --The second and third operands have the same type; the result is of
3536 if (same_type_p (arg2_type, arg3_type))
3537 result_type = arg2_type;
3540 --The second and third operands have arithmetic or enumeration
3541 type; the usual arithmetic conversions are performed to bring
3542 them to a common type, and the result is of that type. */
3543 else if ((ARITHMETIC_TYPE_P (arg2_type)
3544 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3545 && (ARITHMETIC_TYPE_P (arg3_type)
3546 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3548 /* In this case, there is always a common type. */
3549 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3552 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3553 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3554 warning (0, "enumeral mismatch in conditional expression: %qT vs %qT",
3555 arg2_type, arg3_type);
3556 else if (extra_warnings
3557 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3558 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3559 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3560 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3561 warning (0, "enumeral and non-enumeral type in conditional expression");
3563 arg2 = perform_implicit_conversion (result_type, arg2);
3564 arg3 = perform_implicit_conversion (result_type, arg3);
3568 --The second and third operands have pointer type, or one has
3569 pointer type and the other is a null pointer constant; pointer
3570 conversions (_conv.ptr_) and qualification conversions
3571 (_conv.qual_) are performed to bring them to their composite
3572 pointer type (_expr.rel_). The result is of the composite
3575 --The second and third operands have pointer to member type, or
3576 one has pointer to member type and the other is a null pointer
3577 constant; pointer to member conversions (_conv.mem_) and
3578 qualification conversions (_conv.qual_) are performed to bring
3579 them to a common type, whose cv-qualification shall match the
3580 cv-qualification of either the second or the third operand.
3581 The result is of the common type. */
3582 else if ((null_ptr_cst_p (arg2)
3583 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3584 || (null_ptr_cst_p (arg3)
3585 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3586 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3587 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3588 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3590 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3591 arg3, "conditional expression");
3592 if (result_type == error_mark_node)
3593 return error_mark_node;
3594 arg2 = perform_implicit_conversion (result_type, arg2);
3595 arg3 = perform_implicit_conversion (result_type, arg3);
3600 error ("operands to ?: have different types %qT and %qT",
3601 arg2_type, arg3_type);
3602 return error_mark_node;
3606 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3608 /* We can't use result_type below, as fold might have returned a
3613 /* Expand both sides into the same slot, hopefully the target of
3614 the ?: expression. We used to check for TARGET_EXPRs here,
3615 but now we sometimes wrap them in NOP_EXPRs so the test would
3617 if (CLASS_TYPE_P (TREE_TYPE (result)))
3618 result = get_target_expr (result);
3619 /* If this expression is an rvalue, but might be mistaken for an
3620 lvalue, we must add a NON_LVALUE_EXPR. */
3621 result = rvalue (result);
3627 /* OPERAND is an operand to an expression. Perform necessary steps
3628 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3632 prep_operand (tree operand)
3636 if (CLASS_TYPE_P (TREE_TYPE (operand))
3637 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3638 /* Make sure the template type is instantiated now. */
3639 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3645 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3646 OVERLOAD) to the CANDIDATES, returning an updated list of
3647 CANDIDATES. The ARGS are the arguments provided to the call,
3648 without any implicit object parameter. The EXPLICIT_TARGS are
3649 explicit template arguments provided. TEMPLATE_ONLY is true if
3650 only template functions should be considered. CONVERSION_PATH,
3651 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3654 add_candidates (tree fns, tree args,
3655 tree explicit_targs, bool template_only,
3656 tree conversion_path, tree access_path,
3658 struct z_candidate **candidates)
3661 tree non_static_args;
3663 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3664 /* Delay creating the implicit this parameter until it is needed. */
3665 non_static_args = NULL_TREE;
3672 fn = OVL_CURRENT (fns);
3673 /* Figure out which set of arguments to use. */
3674 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3676 /* If this function is a non-static member, prepend the implicit
3677 object parameter. */
3678 if (!non_static_args)
3679 non_static_args = tree_cons (NULL_TREE,
3680 build_this (TREE_VALUE (args)),
3682 fn_args = non_static_args;
3685 /* Otherwise, just use the list of arguments provided. */
3688 if (TREE_CODE (fn) == TEMPLATE_DECL)
3689 add_template_candidate (candidates,
3699 else if (!template_only)
3700 add_function_candidate (candidates,
3707 fns = OVL_NEXT (fns);
3712 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3715 struct z_candidate *candidates = 0, *cand;
3716 tree arglist, fnname;
3718 tree result = NULL_TREE;
3719 bool result_valid_p = false;
3720 enum tree_code code2 = NOP_EXPR;
3725 bool expl_eq_arg1 = false;
3727 if (error_operand_p (arg1)
3728 || error_operand_p (arg2)
3729 || error_operand_p (arg3))
3730 return error_mark_node;
3732 if (code == MODIFY_EXPR)
3734 code2 = TREE_CODE (arg3);
3736 fnname = ansi_assopname (code2);
3739 fnname = ansi_opname (code);
3741 arg1 = prep_operand (arg1);
3747 case VEC_DELETE_EXPR:
3749 /* Use build_op_new_call and build_op_delete_call instead. */
3753 return build_object_call (arg1, arg2);
3755 case TRUTH_ORIF_EXPR:
3756 case TRUTH_ANDIF_EXPR:
3757 case TRUTH_AND_EXPR:
3759 if (COMPARISON_CLASS_P (arg1))
3760 expl_eq_arg1 = true;
3765 arg2 = prep_operand (arg2);
3766 arg3 = prep_operand (arg3);
3768 if (code == COND_EXPR)
3770 if (arg2 == NULL_TREE
3771 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3772 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3773 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3774 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3777 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3778 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3781 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3782 arg2 = integer_zero_node;
3784 arglist = NULL_TREE;
3786 arglist = tree_cons (NULL_TREE, arg3, arglist);
3788 arglist = tree_cons (NULL_TREE, arg2, arglist);
3789 arglist = tree_cons (NULL_TREE, arg1, arglist);
3791 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3792 p = conversion_obstack_alloc (0);
3794 /* Add namespace-scope operators to the list of functions to
3796 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3797 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3798 flags, &candidates);
3799 /* Add class-member operators to the candidate set. */
3800 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3804 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3805 if (fns == error_mark_node)
3807 result = error_mark_node;
3808 goto user_defined_result_ready;
3811 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3813 BASELINK_BINFO (fns),
3814 TYPE_BINFO (TREE_TYPE (arg1)),
3815 flags, &candidates);
3818 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3819 to know about two args; a builtin candidate will always have a first
3820 parameter of type bool. We'll handle that in
3821 build_builtin_candidate. */
3822 if (code == COND_EXPR)
3832 args[2] = NULL_TREE;
3835 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3841 /* For these, the built-in candidates set is empty
3842 [over.match.oper]/3. We don't want non-strict matches
3843 because exact matches are always possible with built-in
3844 operators. The built-in candidate set for COMPONENT_REF
3845 would be empty too, but since there are no such built-in
3846 operators, we accept non-strict matches for them. */
3851 strict_p = pedantic;
3855 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3860 case POSTINCREMENT_EXPR:
3861 case POSTDECREMENT_EXPR:
3862 /* Look for an `operator++ (int)'. If they didn't have
3863 one, then we fall back to the old way of doing things. */
3864 if (flags & LOOKUP_COMPLAIN)
3865 pedwarn ("no %<%D(int)%> declared for postfix %qs, "
3866 "trying prefix operator instead",
3868 operator_name_info[code].name);
3869 if (code == POSTINCREMENT_EXPR)
3870 code = PREINCREMENT_EXPR;
3872 code = PREDECREMENT_EXPR;
3873 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
3877 /* The caller will deal with these. */
3882 result_valid_p = true;
3886 if (flags & LOOKUP_COMPLAIN)
3888 op_error (code, code2, arg1, arg2, arg3, "no match");
3889 print_z_candidates (candidates);
3891 result = error_mark_node;
3897 cand = tourney (candidates);
3900 if (flags & LOOKUP_COMPLAIN)
3902 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3903 print_z_candidates (candidates);
3905 result = error_mark_node;
3907 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3910 *overloaded_p = true;
3912 result = build_over_call (cand, LOOKUP_NORMAL);
3916 /* Give any warnings we noticed during overload resolution. */
3919 struct candidate_warning *w;
3920 for (w = cand->warnings; w; w = w->next)
3921 joust (cand, w->loser, 1);
3924 /* Check for comparison of different enum types. */
3933 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3934 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3935 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3936 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3938 warning (0, "comparison between %q#T and %q#T",
3939 TREE_TYPE (arg1), TREE_TYPE (arg2));
3946 /* We need to strip any leading REF_BIND so that bitfields
3947 don't cause errors. This should not remove any important
3948 conversions, because builtins don't apply to class
3949 objects directly. */
3950 conv = cand->convs[0];
3951 if (conv->kind == ck_ref_bind)
3952 conv = conv->u.next;
3953 arg1 = convert_like (conv, arg1);
3956 conv = cand->convs[1];
3957 if (conv->kind == ck_ref_bind)
3958 conv = conv->u.next;
3959 arg2 = convert_like (conv, arg2);
3963 conv = cand->convs[2];
3964 if (conv->kind == ck_ref_bind)
3965 conv = conv->u.next;
3966 arg3 = convert_like (conv, arg3);
3971 warn_logical_operator (code, arg1, arg2);
3972 expl_eq_arg1 = true;
3977 user_defined_result_ready:
3979 /* Free all the conversions we allocated. */
3980 obstack_free (&conversion_obstack, p);
3982 if (result || result_valid_p)
3989 return build_modify_expr (arg1, code2, arg2);
3992 return build_indirect_ref (arg1, "unary *");
3994 case TRUTH_ANDIF_EXPR:
3995 case TRUTH_ORIF_EXPR:
3996 case TRUTH_AND_EXPR:
3999 warn_logical_operator (code, arg1, arg2);
4003 case TRUNC_DIV_EXPR:
4014 case TRUNC_MOD_EXPR:
4018 return cp_build_binary_op (code, arg1, arg2);
4020 case UNARY_PLUS_EXPR:
4023 case TRUTH_NOT_EXPR:
4024 case PREINCREMENT_EXPR:
4025 case POSTINCREMENT_EXPR:
4026 case PREDECREMENT_EXPR:
4027 case POSTDECREMENT_EXPR:
4030 return build_unary_op (code, arg1, candidates != 0);
4033 return build_array_ref (arg1, arg2);
4036 return build_conditional_expr (arg1, arg2, arg3);
4039 return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2);
4041 /* The caller will deal with these. */
4053 /* Build a call to operator delete. This has to be handled very specially,
4054 because the restrictions on what signatures match are different from all
4055 other call instances. For a normal delete, only a delete taking (void *)
4056 or (void *, size_t) is accepted. For a placement delete, only an exact
4057 match with the placement new is accepted.
4059 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4060 ADDR is the pointer to be deleted.
4061 SIZE is the size of the memory block to be deleted.
4062 GLOBAL_P is true if the delete-expression should not consider
4063 class-specific delete operators.
4064 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4066 If this call to "operator delete" is being generated as part to
4067 deallocate memory allocated via a new-expression (as per [expr.new]
4068 which requires that if the initialization throws an exception then
4069 we call a deallocation function), then ALLOC_FN is the allocation
4073 build_op_delete_call (enum tree_code code, tree addr, tree size,
4074 bool global_p, tree placement,
4077 tree fn = NULL_TREE;
4078 tree fns, fnname, argtypes, type;
4081 if (addr == error_mark_node)
4082 return error_mark_node;
4084 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
4086 fnname = ansi_opname (code);
4088 if (CLASS_TYPE_P (type)
4089 && COMPLETE_TYPE_P (complete_type (type))
4093 If the result of the lookup is ambiguous or inaccessible, or if
4094 the lookup selects a placement deallocation function, the
4095 program is ill-formed.
4097 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4099 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
4100 if (fns == error_mark_node)
4101 return error_mark_node;
4106 if (fns == NULL_TREE)
4107 fns = lookup_name_nonclass (fnname);
4109 /* Strip const and volatile from addr. */
4110 addr = cp_convert (ptr_type_node, addr);
4114 /* Get the parameter types for the allocation function that is
4116 gcc_assert (alloc_fn != NULL_TREE);
4117 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
4121 /* First try it without the size argument. */
4122 argtypes = void_list_node;
4125 /* We make two tries at finding a matching `operator delete'. On
4126 the first pass, we look for a one-operator (or placement)
4127 operator delete. If we're not doing placement delete, then on
4128 the second pass we look for a two-argument delete. */
4129 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4131 /* Go through the `operator delete' functions looking for one
4132 with a matching type. */
4133 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4139 /* The first argument must be "void *". */
4140 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4141 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4144 /* On the first pass, check the rest of the arguments. */
4150 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4158 /* On the second pass, look for a function with exactly two
4159 arguments: "void *" and "size_t". */
4161 /* For "operator delete(void *, ...)" there will be
4162 no second argument, but we will not get an exact
4165 && same_type_p (TREE_VALUE (t), size_type_node)
4166 && TREE_CHAIN (t) == void_list_node)
4170 /* If we found a match, we're done. */
4175 /* If we have a matching function, call it. */
4178 /* Make sure we have the actual function, and not an
4180 fn = OVL_CURRENT (fn);
4182 /* If the FN is a member function, make sure that it is
4184 if (DECL_CLASS_SCOPE_P (fn))
4185 perform_or_defer_access_check (TYPE_BINFO (type), fn, fn);
4189 /* The placement args might not be suitable for overload
4190 resolution at this point, so build the call directly. */
4191 int nargs = call_expr_nargs (placement);
4192 tree *argarray = (tree *) alloca (nargs * sizeof (tree));
4195 for (i = 1; i < nargs; i++)
4196 argarray[i] = CALL_EXPR_ARG (placement, i);
4198 return build_cxx_call (fn, nargs, argarray);
4204 args = tree_cons (NULL_TREE, addr, NULL_TREE);
4206 args = tree_cons (NULL_TREE, addr,
4207 build_tree_list (NULL_TREE, size));
4208 return build_function_call (fn, args);
4214 If no unambiguous matching deallocation function can be found,
4215 propagating the exception does not cause the object's memory to
4220 warning (0, "no corresponding deallocation function for `%D'",
4225 error ("no suitable %<operator %s%> for %qT",
4226 operator_name_info[(int)code].name, type);
4227 return error_mark_node;
4230 /* If the current scope isn't allowed to access DECL along
4231 BASETYPE_PATH, give an error. The most derived class in
4232 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4233 the declaration to use in the error diagnostic. */
4236 enforce_access (tree basetype_path, tree decl, tree diag_decl)
4238 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4240 if (!accessible_p (basetype_path, decl, true))
4242 if (TREE_PRIVATE (decl))
4243 error ("%q+#D is private", diag_decl);
4244 else if (TREE_PROTECTED (decl))
4245 error ("%q+#D is protected", diag_decl);
4247 error ("%q+#D is inaccessible", diag_decl);
4248 error ("within this context");
4255 /* Check that a callable constructor to initialize a temporary of
4256 TYPE from an EXPR exists. */
4259 check_constructor_callable (tree type, tree expr)
4261 build_special_member_call (NULL_TREE,
4262 complete_ctor_identifier,
4263 build_tree_list (NULL_TREE, expr),
4265 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING
4266 | LOOKUP_NO_CONVERSION
4267 | LOOKUP_CONSTRUCTOR_CALLABLE);
4270 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4271 bitwise or of LOOKUP_* values. If any errors are warnings are
4272 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4273 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4277 build_temp (tree expr, tree type, int flags,
4278 diagnostic_fn_t *diagnostic_fn)
4282 savew = warningcount, savee = errorcount;
4283 expr = build_special_member_call (NULL_TREE,
4284 complete_ctor_identifier,
4285 build_tree_list (NULL_TREE, expr),
4287 if (warningcount > savew)
4288 *diagnostic_fn = warning0;
4289 else if (errorcount > savee)
4290 *diagnostic_fn = error;
4292 *diagnostic_fn = NULL;
4296 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4297 EXPR is implicitly converted to type TOTYPE.
4298 FN and ARGNUM are used for diagnostics. */
4301 conversion_null_warnings (tree totype, tree expr, tree fn, int argnum)
4303 tree t = non_reference (totype);
4305 /* Issue warnings about peculiar, but valid, uses of NULL. */
4306 if (expr == null_node && TREE_CODE (t) != BOOLEAN_TYPE && ARITHMETIC_TYPE_P (t))
4309 warning (OPT_Wconversion, "passing NULL to non-pointer argument %P of %qD",
4312 warning (OPT_Wconversion, "converting to non-pointer type %qT from NULL", t);
4315 /* Issue warnings if "false" is converted to a NULL pointer */
4316 else if (expr == boolean_false_node && fn && POINTER_TYPE_P (t))
4317 warning (OPT_Wconversion,
4318 "converting %<false%> to pointer type for argument %P of %qD",
4322 /* Perform the conversions in CONVS on the expression EXPR. FN and
4323 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4324 indicates the `this' argument of a method. INNER is nonzero when
4325 being called to continue a conversion chain. It is negative when a
4326 reference binding will be applied, positive otherwise. If
4327 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4328 conversions will be emitted if appropriate. If C_CAST_P is true,
4329 this conversion is coming from a C-style cast; in that case,
4330 conversions to inaccessible bases are permitted. */
4333 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4334 int inner, bool issue_conversion_warnings,
4337 tree totype = convs->type;
4338 diagnostic_fn_t diagnostic_fn;
4341 && convs->kind != ck_user
4342 && convs->kind != ck_ambig
4343 && convs->kind != ck_ref_bind)
4345 conversion *t = convs;
4346 for (; t; t = convs->u.next)
4348 if (t->kind == ck_user || !t->bad_p)
4350 expr = convert_like_real (t, expr, fn, argnum, 1,
4351 /*issue_conversion_warnings=*/false,
4352 /*c_cast_p=*/false);
4355 else if (t->kind == ck_ambig)
4356 return convert_like_real (t, expr, fn, argnum, 1,
4357 /*issue_conversion_warnings=*/false,
4358 /*c_cast_p=*/false);
4359 else if (t->kind == ck_identity)
4362 pedwarn ("invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4364 pedwarn (" initializing argument %P of %qD", argnum, fn);
4365 return cp_convert (totype, expr);
4368 if (issue_conversion_warnings)
4369 conversion_null_warnings (totype, expr, fn, argnum);
4371 switch (convs->kind)
4375 struct z_candidate *cand = convs->cand;
4376 tree convfn = cand->fn;
4378 expr = build_over_call (cand, LOOKUP_NORMAL);
4380 /* If this is a constructor or a function returning an aggr type,
4381 we need to build up a TARGET_EXPR. */
4382 if (DECL_CONSTRUCTOR_P (convfn))
4383 expr = build_cplus_new (totype, expr);
4385 /* The result of the call is then used to direct-initialize the object
4386 that is the destination of the copy-initialization. [dcl.init]
4388 Note that this step is not reflected in the conversion sequence;
4389 it affects the semantics when we actually perform the
4390 conversion, but is not considered during overload resolution.
4392 If the target is a class, that means call a ctor. */
4393 if (IS_AGGR_TYPE (totype)
4394 && (inner >= 0 || !lvalue_p (expr)))
4398 /* Core issue 84, now a DR, says that we don't
4399 allow UDCs for these args (which deliberately
4400 breaks copy-init of an auto_ptr<Base> from an
4401 auto_ptr<Derived>). */
4402 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION,
4409 (" initializing argument %P of %qD from result of %qD",
4410 argnum, fn, convfn);
4413 (" initializing temporary from result of %qD", convfn);
4415 expr = build_cplus_new (totype, expr);
4420 if (type_unknown_p (expr))
4421 expr = instantiate_type (totype, expr, tf_warning_or_error);
4422 /* Convert a constant to its underlying value, unless we are
4423 about to bind it to a reference, in which case we need to
4424 leave it as an lvalue. */
4426 expr = decl_constant_value (expr);
4427 if (convs->check_copy_constructor_p)
4428 check_constructor_callable (totype, expr);
4431 /* Call build_user_type_conversion again for the error. */
4432 return build_user_type_conversion
4433 (totype, convs->u.expr, LOOKUP_NORMAL);
4439 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4440 convs->kind == ck_ref_bind ? -1 : 1,
4441 convs->kind == ck_ref_bind ? issue_conversion_warnings : false,
4443 if (expr == error_mark_node)
4444 return error_mark_node;
4446 switch (convs->kind)
4449 expr = convert_bitfield_to_declared_type (expr);
4450 if (! IS_AGGR_TYPE (totype))
4452 /* Else fall through. */
4454 if (convs->kind == ck_base && !convs->need_temporary_p)
4456 /* We are going to bind a reference directly to a base-class
4457 subobject of EXPR. */
4458 if (convs->check_copy_constructor_p)
4459 check_constructor_callable (TREE_TYPE (expr), expr);
4460 /* Build an expression for `*((base*) &expr)'. */
4461 expr = build_unary_op (ADDR_EXPR, expr, 0);
4462 expr = convert_to_base (expr, build_pointer_type (totype),
4463 !c_cast_p, /*nonnull=*/true);
4464 expr = build_indirect_ref (expr, "implicit conversion");
4468 /* Copy-initialization where the cv-unqualified version of the source
4469 type is the same class as, or a derived class of, the class of the
4470 destination [is treated as direct-initialization]. [dcl.init] */
4471 expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
4473 if (diagnostic_fn && fn)
4474 diagnostic_fn (" initializing argument %P of %qD", argnum, fn);
4475 return build_cplus_new (totype, expr);
4479 tree ref_type = totype;
4481 /* If necessary, create a temporary.
4483 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
4484 that need temporaries, even when their types are reference
4485 compatible with the type of reference being bound, so the
4486 upcoming call to build_unary_op (ADDR_EXPR, expr, ...)
4488 if (convs->need_temporary_p
4489 || TREE_CODE (expr) == CONSTRUCTOR
4490 || TREE_CODE (expr) == VA_ARG_EXPR)
4492 tree type = convs->u.next->type;
4493 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4495 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type))
4496 && !TYPE_REF_IS_RVALUE (ref_type))
4498 /* If the reference is volatile or non-const, we
4499 cannot create a temporary. */
4500 if (lvalue & clk_bitfield)
4501 error ("cannot bind bitfield %qE to %qT",
4503 else if (lvalue & clk_packed)
4504 error ("cannot bind packed field %qE to %qT",
4507 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4508 return error_mark_node;
4510 /* If the source is a packed field, and we must use a copy
4511 constructor, then building the target expr will require
4512 binding the field to the reference parameter to the
4513 copy constructor, and we'll end up with an infinite
4514 loop. If we can use a bitwise copy, then we'll be
4516 if ((lvalue & clk_packed)
4517 && CLASS_TYPE_P (type)
4518 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4520 error ("cannot bind packed field %qE to %qT",
4522 return error_mark_node;
4524 expr = build_target_expr_with_type (expr, type);
4527 /* Take the address of the thing to which we will bind the
4529 expr = build_unary_op (ADDR_EXPR, expr, 1);
4530 if (expr == error_mark_node)
4531 return error_mark_node;
4533 /* Convert it to a pointer to the type referred to by the
4534 reference. This will adjust the pointer if a derived to
4535 base conversion is being performed. */
4536 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4538 /* Convert the pointer to the desired reference type. */
4539 return build_nop (ref_type, expr);
4543 return decay_conversion (expr);
4546 /* Warn about deprecated conversion if appropriate. */
4547 string_conv_p (totype, expr, 1);
4552 expr = convert_to_base (expr, totype, !c_cast_p,
4554 return build_nop (totype, expr);
4557 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4564 if (issue_conversion_warnings)
4565 expr = convert_and_check (totype, expr);
4567 expr = convert (totype, expr);
4572 /* Build a call to __builtin_trap. */
4575 call_builtin_trap (void)
4577 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4579 gcc_assert (fn != NULL);
4580 fn = build_call_n (fn, 0);
4584 /* ARG is being passed to a varargs function. Perform any conversions
4585 required. Return the converted value. */
4588 convert_arg_to_ellipsis (tree arg)
4592 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4593 standard conversions are performed. */
4594 arg = decay_conversion (arg);
4597 If the argument has integral or enumeration type that is subject
4598 to the integral promotions (_conv.prom_), or a floating point
4599 type that is subject to the floating point promotion
4600 (_conv.fpprom_), the value of the argument is converted to the
4601 promoted type before the call. */
4602 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4603 && (TYPE_PRECISION (TREE_TYPE (arg))
4604 < TYPE_PRECISION (double_type_node)))
4605 arg = convert_to_real (double_type_node, arg);
4606 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4607 arg = perform_integral_promotions (arg);
4609 arg = require_complete_type (arg);
4611 if (arg != error_mark_node
4612 && !pod_type_p (TREE_TYPE (arg)))
4614 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4615 here and do a bitwise copy, but now cp_expr_size will abort if we
4617 If the call appears in the context of a sizeof expression,
4618 there is no need to emit a warning, since the expression won't be
4619 evaluated. We keep the builtin_trap just as a safety check. */
4620 if (!skip_evaluation)
4621 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4622 "call will abort at runtime", TREE_TYPE (arg));
4623 arg = call_builtin_trap ();
4624 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4631 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4634 build_x_va_arg (tree expr, tree type)
4636 if (processing_template_decl)
4637 return build_min (VA_ARG_EXPR, type, expr);
4639 type = complete_type_or_else (type, NULL_TREE);
4641 if (expr == error_mark_node || !type)
4642 return error_mark_node;
4644 if (! pod_type_p (type))
4646 /* Remove reference types so we don't ICE later on. */
4647 tree type1 = non_reference (type);
4648 /* Undefined behavior [expr.call] 5.2.2/7. */
4649 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4650 "call will abort at runtime", type);
4651 expr = convert (build_pointer_type (type1), null_node);
4652 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4653 call_builtin_trap (), expr);
4654 expr = build_indirect_ref (expr, NULL);
4658 return build_va_arg (expr, type);
4661 /* TYPE has been given to va_arg. Apply the default conversions which
4662 would have happened when passed via ellipsis. Return the promoted
4663 type, or the passed type if there is no change. */
4666 cxx_type_promotes_to (tree type)
4670 /* Perform the array-to-pointer and function-to-pointer
4672 type = type_decays_to (type);
4674 promote = type_promotes_to (type);
4675 if (same_type_p (type, promote))
4681 /* ARG is a default argument expression being passed to a parameter of
4682 the indicated TYPE, which is a parameter to FN. Do any required
4683 conversions. Return the converted value. */
4686 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4688 /* If the ARG is an unparsed default argument expression, the
4689 conversion cannot be performed. */
4690 if (TREE_CODE (arg) == DEFAULT_ARG)
4692 error ("the default argument for parameter %d of %qD has "
4693 "not yet been parsed",
4695 return error_mark_node;
4698 if (fn && DECL_TEMPLATE_INFO (fn))
4699 arg = tsubst_default_argument (fn, type, arg);
4701 arg = break_out_target_exprs (arg);
4703 if (TREE_CODE (arg) == CONSTRUCTOR)
4705 arg = digest_init (type, arg);
4706 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4707 "default argument", fn, parmnum);
4711 /* We must make a copy of ARG, in case subsequent processing
4712 alters any part of it. For example, during gimplification a
4713 cast of the form (T) &X::f (where "f" is a member function)
4714 will lead to replacing the PTRMEM_CST for &X::f with a
4715 VAR_DECL. We can avoid the copy for constants, since they
4716 are never modified in place. */
4717 if (!CONSTANT_CLASS_P (arg))
4718 arg = unshare_expr (arg);
4719 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4720 "default argument", fn, parmnum);
4721 arg = convert_for_arg_passing (type, arg);
4727 /* Returns the type which will really be used for passing an argument of
4731 type_passed_as (tree type)
4733 /* Pass classes with copy ctors by invisible reference. */
4734 if (TREE_ADDRESSABLE (type))
4736 type = build_reference_type (type);
4737 /* There are no other pointers to this temporary. */
4738 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4740 else if (targetm.calls.promote_prototypes (type)
4741 && INTEGRAL_TYPE_P (type)
4742 && COMPLETE_TYPE_P (type)
4743 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4744 TYPE_SIZE (integer_type_node)))
4745 type = integer_type_node;
4750 /* Actually perform the appropriate conversion. */
4753 convert_for_arg_passing (tree type, tree val)
4755 val = convert_bitfield_to_declared_type (val);
4756 if (val == error_mark_node)
4758 /* Pass classes with copy ctors by invisible reference. */
4759 else if (TREE_ADDRESSABLE (type))
4760 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4761 else if (targetm.calls.promote_prototypes (type)
4762 && INTEGRAL_TYPE_P (type)
4763 && COMPLETE_TYPE_P (type)
4764 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4765 TYPE_SIZE (integer_type_node)))
4766 val = perform_integral_promotions (val);
4767 if (warn_missing_format_attribute)
4769 tree rhstype = TREE_TYPE (val);
4770 const enum tree_code coder = TREE_CODE (rhstype);
4771 const enum tree_code codel = TREE_CODE (type);
4772 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4774 && check_missing_format_attribute (type, rhstype))
4775 warning (OPT_Wmissing_format_attribute,
4776 "argument of function call might be a candidate for a format attribute");
4781 /* Returns true iff FN is a function with magic varargs, i.e. ones for
4782 which no conversions at all should be done. This is true for some
4783 builtins which don't act like normal functions. */
4786 magic_varargs_p (tree fn)
4788 if (DECL_BUILT_IN (fn))
4789 switch (DECL_FUNCTION_CODE (fn))
4791 case BUILT_IN_CLASSIFY_TYPE:
4792 case BUILT_IN_CONSTANT_P:
4793 case BUILT_IN_NEXT_ARG:
4794 case BUILT_IN_STDARG_START:
4795 case BUILT_IN_VA_START:
4804 /* Subroutine of the various build_*_call functions. Overload resolution
4805 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4806 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4807 bitmask of various LOOKUP_* flags which apply to the call itself. */
4810 build_over_call (struct z_candidate *cand, int flags)
4813 tree args = cand->args;
4814 conversion **convs = cand->convs;
4816 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4825 /* In a template, there is no need to perform all of the work that
4826 is normally done. We are only interested in the type of the call
4827 expression, i.e., the return type of the function. Any semantic
4828 errors will be deferred until the template is instantiated. */
4829 if (processing_template_decl)
4833 return_type = TREE_TYPE (TREE_TYPE (fn));
4834 expr = build_call_list (return_type, fn, args);
4835 if (TREE_THIS_VOLATILE (fn) && cfun)
4836 current_function_returns_abnormally = 1;
4837 if (!VOID_TYPE_P (return_type))
4838 require_complete_type (return_type);
4839 return convert_from_reference (expr);
4842 /* Give any warnings we noticed during overload resolution. */
4845 struct candidate_warning *w;
4846 for (w = cand->warnings; w; w = w->next)
4847 joust (cand, w->loser, 1);
4850 if (DECL_FUNCTION_MEMBER_P (fn))
4852 /* If FN is a template function, two cases must be considered.
4857 template <class T> void f();
4859 template <class T> struct B {
4863 struct C : A, B<int> {
4865 using B<int>::g; // #2
4868 In case #1 where `A::f' is a member template, DECL_ACCESS is
4869 recorded in the primary template but not in its specialization.
4870 We check access of FN using its primary template.
4872 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
4873 because it is a member of class template B, DECL_ACCESS is
4874 recorded in the specialization `B<int>::g'. We cannot use its
4875 primary template because `B<T>::g' and `B<int>::g' may have
4876 different access. */
4877 if (DECL_TEMPLATE_INFO (fn)
4878 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
4879 perform_or_defer_access_check (cand->access_path,
4880 DECL_TI_TEMPLATE (fn), fn);
4882 perform_or_defer_access_check (cand->access_path, fn, fn);
4885 if (args && TREE_CODE (args) != TREE_LIST)
4886 args = build_tree_list (NULL_TREE, args);
4889 /* Find maximum size of vector to hold converted arguments. */
4890 parmlen = list_length (parm);
4891 nargs = list_length (args);
4892 if (parmlen > nargs)
4894 argarray = (tree *) alloca (nargs * sizeof (tree));
4896 /* The implicit parameters to a constructor are not considered by overload
4897 resolution, and must be of the proper type. */
4898 if (DECL_CONSTRUCTOR_P (fn))
4900 argarray[j++] = TREE_VALUE (arg);
4901 arg = TREE_CHAIN (arg);
4902 parm = TREE_CHAIN (parm);
4903 /* We should never try to call the abstract constructor. */
4904 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
4906 if (DECL_HAS_VTT_PARM_P (fn))
4908 argarray[j++] = TREE_VALUE (arg);
4909 arg = TREE_CHAIN (arg);
4910 parm = TREE_CHAIN (parm);
4913 /* Bypass access control for 'this' parameter. */
4914 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4916 tree parmtype = TREE_VALUE (parm);
4917 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4921 if (convs[i]->bad_p)
4922 pedwarn ("passing %qT as %<this%> argument of %q#D discards qualifiers",
4923 TREE_TYPE (argtype), fn);
4925 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4926 X is called for an object that is not of type X, or of a type
4927 derived from X, the behavior is undefined.
4929 So we can assume that anything passed as 'this' is non-null, and
4930 optimize accordingly. */
4931 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
4932 /* Convert to the base in which the function was declared. */
4933 gcc_assert (cand->conversion_path != NULL_TREE);
4934 converted_arg = build_base_path (PLUS_EXPR,
4936 cand->conversion_path,
4938 /* Check that the base class is accessible. */
4939 if (!accessible_base_p (TREE_TYPE (argtype),
4940 BINFO_TYPE (cand->conversion_path), true))
4941 error ("%qT is not an accessible base of %qT",
4942 BINFO_TYPE (cand->conversion_path),
4943 TREE_TYPE (argtype));
4944 /* If fn was found by a using declaration, the conversion path
4945 will be to the derived class, not the base declaring fn. We
4946 must convert from derived to base. */
4947 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4948 TREE_TYPE (parmtype), ba_unique, NULL);
4949 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4952 argarray[j++] = converted_arg;
4953 parm = TREE_CHAIN (parm);
4954 arg = TREE_CHAIN (arg);
4960 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4962 tree type = TREE_VALUE (parm);
4966 /* Don't make a copy here if build_call is going to. */
4967 if (conv->kind == ck_rvalue
4968 && !TREE_ADDRESSABLE (complete_type (type)))
4969 conv = conv->u.next;
4971 val = convert_like_with_context
4972 (conv, TREE_VALUE (arg), fn, i - is_method);
4974 val = convert_for_arg_passing (type, val);
4975 argarray[j++] = val;
4978 /* Default arguments */
4979 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4980 argarray[j++] = convert_default_arg (TREE_VALUE (parm),
4981 TREE_PURPOSE (parm),
4984 for (; arg; arg = TREE_CHAIN (arg))
4986 tree a = TREE_VALUE (arg);
4987 if (magic_varargs_p (fn))
4988 /* Do no conversions for magic varargs. */;
4990 a = convert_arg_to_ellipsis (a);
4994 gcc_assert (j <= nargs);
4997 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4998 nargs, argarray, TYPE_ARG_TYPES (TREE_TYPE (fn)));
5000 /* Avoid actually calling copy constructors and copy assignment operators,
5003 if (! flag_elide_constructors)
5004 /* Do things the hard way. */;
5005 else if (cand->num_convs == 1
5006 && (DECL_COPY_CONSTRUCTOR_P (fn)
5007 || DECL_MOVE_CONSTRUCTOR_P (fn)))
5010 arg = argarray[num_artificial_parms_for (fn)];
5012 /* Pull out the real argument, disregarding const-correctness. */
5014 while (TREE_CODE (targ) == NOP_EXPR
5015 || TREE_CODE (targ) == NON_LVALUE_EXPR
5016 || TREE_CODE (targ) == CONVERT_EXPR)
5017 targ = TREE_OPERAND (targ, 0);
5018 if (TREE_CODE (targ) == ADDR_EXPR)
5020 targ = TREE_OPERAND (targ, 0);
5021 if (!same_type_ignoring_top_level_qualifiers_p
5022 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
5031 arg = build_indirect_ref (arg, 0);
5033 /* [class.copy]: the copy constructor is implicitly defined even if
5034 the implementation elided its use. */
5035 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
5038 /* If we're creating a temp and we already have one, don't create a
5039 new one. If we're not creating a temp but we get one, use
5040 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5041 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5042 temp or an INIT_EXPR otherwise. */
5043 if (integer_zerop (TREE_VALUE (args)))
5045 if (TREE_CODE (arg) == TARGET_EXPR)
5047 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5048 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
5050 else if (TREE_CODE (arg) == TARGET_EXPR
5051 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
5053 tree to = stabilize_reference
5054 (build_indirect_ref (TREE_VALUE (args), 0));
5056 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
5060 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
5062 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
5064 tree to = stabilize_reference
5065 (build_indirect_ref (argarray[0], 0));
5066 tree type = TREE_TYPE (to);
5067 tree as_base = CLASSTYPE_AS_BASE (type);
5070 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
5072 arg = build_indirect_ref (arg, 0);
5073 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
5077 /* We must only copy the non-tail padding parts.
5078 Use __builtin_memcpy for the bitwise copy. */
5080 tree arg0, arg1, arg2, t;
5082 arg2 = TYPE_SIZE_UNIT (as_base);
5084 arg0 = build_unary_op (ADDR_EXPR, to, 0);
5085 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
5086 t = build_call_n (t, 3, arg0, arg1, arg2);
5088 t = convert (TREE_TYPE (arg0), t);
5089 val = build_indirect_ref (t, 0);
5097 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
5100 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (argarray[0])),
5103 gcc_assert (binfo && binfo != error_mark_node);
5105 argarray[0] = build_base_path (PLUS_EXPR, argarray[0], binfo, 1);
5106 if (TREE_SIDE_EFFECTS (argarray[0]))
5107 argarray[0] = save_expr (argarray[0]);
5108 t = build_pointer_type (TREE_TYPE (fn));
5109 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
5110 fn = build_java_interface_fn_ref (fn, argarray[0]);
5112 fn = build_vfn_ref (argarray[0], DECL_VINDEX (fn));
5115 else if (DECL_INLINE (fn))
5116 fn = inline_conversion (fn);
5118 fn = build_addr_func (fn);
5120 return build_cxx_call (fn, nargs, argarray);
5123 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5124 This function performs no overload resolution, conversion, or other
5125 high-level operations. */
5128 build_cxx_call (tree fn, int nargs, tree *argarray)
5132 fn = build_call_a (fn, nargs, argarray);
5134 /* If this call might throw an exception, note that fact. */
5135 fndecl = get_callee_fndecl (fn);
5136 if ((!fndecl || !TREE_NOTHROW (fndecl))
5137 && at_function_scope_p ()
5139 cp_function_chain->can_throw = 1;
5141 /* Some built-in function calls will be evaluated at compile-time in
5143 fn = fold_if_not_in_template (fn);
5145 if (VOID_TYPE_P (TREE_TYPE (fn)))
5148 fn = require_complete_type (fn);
5149 if (fn == error_mark_node)
5150 return error_mark_node;
5152 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
5153 fn = build_cplus_new (TREE_TYPE (fn), fn);
5154 return convert_from_reference (fn);
5157 static GTY(()) tree java_iface_lookup_fn;
5159 /* Make an expression which yields the address of the Java interface
5160 method FN. This is achieved by generating a call to libjava's
5161 _Jv_LookupInterfaceMethodIdx(). */
5164 build_java_interface_fn_ref (tree fn, tree instance)
5166 tree lookup_fn, method, idx;
5167 tree klass_ref, iface, iface_ref;
5170 if (!java_iface_lookup_fn)
5172 tree endlink = build_void_list_node ();
5173 tree t = tree_cons (NULL_TREE, ptr_type_node,
5174 tree_cons (NULL_TREE, ptr_type_node,
5175 tree_cons (NULL_TREE, java_int_type_node,
5177 java_iface_lookup_fn
5178 = add_builtin_function ("_Jv_LookupInterfaceMethodIdx",
5179 build_function_type (ptr_type_node, t),
5180 0, NOT_BUILT_IN, NULL, NULL_TREE);
5183 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5184 This is the first entry in the vtable. */
5185 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
5188 /* Get the java.lang.Class pointer for the interface being called. */
5189 iface = DECL_CONTEXT (fn);
5190 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5191 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5192 || DECL_CONTEXT (iface_ref) != iface)
5194 error ("could not find class$ field in java interface type %qT",
5196 return error_mark_node;
5198 iface_ref = build_address (iface_ref);
5199 iface_ref = convert (build_pointer_type (iface), iface_ref);
5201 /* Determine the itable index of FN. */
5203 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5205 if (!DECL_VIRTUAL_P (method))
5211 idx = build_int_cst (NULL_TREE, i);
5213 lookup_fn = build1 (ADDR_EXPR,
5214 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5215 java_iface_lookup_fn);
5216 return build_call_nary (ptr_type_node, lookup_fn,
5217 3, klass_ref, iface_ref, idx);
5220 /* Returns the value to use for the in-charge parameter when making a
5221 call to a function with the indicated NAME.
5223 FIXME:Can't we find a neater way to do this mapping? */
5226 in_charge_arg_for_name (tree name)
5228 if (name == base_ctor_identifier
5229 || name == base_dtor_identifier)
5230 return integer_zero_node;
5231 else if (name == complete_ctor_identifier)
5232 return integer_one_node;
5233 else if (name == complete_dtor_identifier)
5234 return integer_two_node;
5235 else if (name == deleting_dtor_identifier)
5236 return integer_three_node;
5238 /* This function should only be called with one of the names listed
5244 /* Build a call to a constructor, destructor, or an assignment
5245 operator for INSTANCE, an expression with class type. NAME
5246 indicates the special member function to call; ARGS are the
5247 arguments. BINFO indicates the base of INSTANCE that is to be
5248 passed as the `this' parameter to the member function called.
5250 FLAGS are the LOOKUP_* flags to use when processing the call.
5252 If NAME indicates a complete object constructor, INSTANCE may be
5253 NULL_TREE. In this case, the caller will call build_cplus_new to
5254 store the newly constructed object into a VAR_DECL. */
5257 build_special_member_call (tree instance, tree name, tree args,
5258 tree binfo, int flags)
5261 /* The type of the subobject to be constructed or destroyed. */
5264 gcc_assert (name == complete_ctor_identifier
5265 || name == base_ctor_identifier
5266 || name == complete_dtor_identifier
5267 || name == base_dtor_identifier
5268 || name == deleting_dtor_identifier
5269 || name == ansi_assopname (NOP_EXPR));
5272 /* Resolve the name. */
5273 if (!complete_type_or_else (binfo, NULL_TREE))
5274 return error_mark_node;
5276 binfo = TYPE_BINFO (binfo);
5279 gcc_assert (binfo != NULL_TREE);
5281 class_type = BINFO_TYPE (binfo);
5283 /* Handle the special case where INSTANCE is NULL_TREE. */
5284 if (name == complete_ctor_identifier && !instance)
5286 instance = build_int_cst (build_pointer_type (class_type), 0);
5287 instance = build1 (INDIRECT_REF, class_type, instance);
5291 if (name == complete_dtor_identifier
5292 || name == base_dtor_identifier
5293 || name == deleting_dtor_identifier)
5294 gcc_assert (args == NULL_TREE);
5296 /* Convert to the base class, if necessary. */
5297 if (!same_type_ignoring_top_level_qualifiers_p
5298 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5300 if (name != ansi_assopname (NOP_EXPR))
5301 /* For constructors and destructors, either the base is
5302 non-virtual, or it is virtual but we are doing the
5303 conversion from a constructor or destructor for the
5304 complete object. In either case, we can convert
5306 instance = convert_to_base_statically (instance, binfo);
5308 /* However, for assignment operators, we must convert
5309 dynamically if the base is virtual. */
5310 instance = build_base_path (PLUS_EXPR, instance,
5311 binfo, /*nonnull=*/1);
5315 gcc_assert (instance != NULL_TREE);
5317 fns = lookup_fnfields (binfo, name, 1);
5319 /* When making a call to a constructor or destructor for a subobject
5320 that uses virtual base classes, pass down a pointer to a VTT for
5322 if ((name == base_ctor_identifier
5323 || name == base_dtor_identifier)
5324 && CLASSTYPE_VBASECLASSES (class_type))
5329 /* If the current function is a complete object constructor
5330 or destructor, then we fetch the VTT directly.
5331 Otherwise, we look it up using the VTT we were given. */
5332 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5333 vtt = decay_conversion (vtt);
5334 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5335 build2 (EQ_EXPR, boolean_type_node,
5336 current_in_charge_parm, integer_zero_node),
5339 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5340 sub_vtt = build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtt), vtt,
5341 BINFO_SUBVTT_INDEX (binfo));
5343 args = tree_cons (NULL_TREE, sub_vtt, args);
5346 return build_new_method_call (instance, fns, args,
5347 TYPE_BINFO (BINFO_TYPE (binfo)),
5348 flags, /*fn=*/NULL);
5351 /* Return the NAME, as a C string. The NAME indicates a function that
5352 is a member of TYPE. *FREE_P is set to true if the caller must
5353 free the memory returned.
5355 Rather than go through all of this, we should simply set the names
5356 of constructors and destructors appropriately, and dispense with
5357 ctor_identifier, dtor_identifier, etc. */
5360 name_as_c_string (tree name, tree type, bool *free_p)
5364 /* Assume that we will not allocate memory. */
5366 /* Constructors and destructors are special. */
5367 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5370 = (char *) IDENTIFIER_POINTER (constructor_name (type));
5371 /* For a destructor, add the '~'. */
5372 if (name == complete_dtor_identifier
5373 || name == base_dtor_identifier
5374 || name == deleting_dtor_identifier)
5376 pretty_name = concat ("~", pretty_name, NULL);
5377 /* Remember that we need to free the memory allocated. */
5381 else if (IDENTIFIER_TYPENAME_P (name))
5383 pretty_name = concat ("operator ",
5384 type_as_string (TREE_TYPE (name),
5385 TFF_PLAIN_IDENTIFIER),
5387 /* Remember that we need to free the memory allocated. */
5391 pretty_name = (char *) IDENTIFIER_POINTER (name);
5396 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
5397 be set, upon return, to the function called. */
5400 build_new_method_call (tree instance, tree fns, tree args,
5401 tree conversion_path, int flags,
5404 struct z_candidate *candidates = 0, *cand;
5405 tree explicit_targs = NULL_TREE;
5406 tree basetype = NULL_TREE;
5409 tree mem_args = NULL_TREE, instance_ptr;
5415 int template_only = 0;
5422 gcc_assert (instance != NULL_TREE);
5424 /* We don't know what function we're going to call, yet. */
5428 if (error_operand_p (instance)
5429 || error_operand_p (fns)
5430 || args == error_mark_node)
5431 return error_mark_node;
5433 if (!BASELINK_P (fns))
5435 error ("call to non-function %qD", fns);
5436 return error_mark_node;
5439 orig_instance = instance;
5443 /* Dismantle the baselink to collect all the information we need. */
5444 if (!conversion_path)
5445 conversion_path = BASELINK_BINFO (fns);
5446 access_binfo = BASELINK_ACCESS_BINFO (fns);
5447 optype = BASELINK_OPTYPE (fns);
5448 fns = BASELINK_FUNCTIONS (fns);
5449 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5451 explicit_targs = TREE_OPERAND (fns, 1);
5452 fns = TREE_OPERAND (fns, 0);
5455 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5456 || TREE_CODE (fns) == TEMPLATE_DECL
5457 || TREE_CODE (fns) == OVERLOAD);
5458 fn = get_first_fn (fns);
5459 name = DECL_NAME (fn);
5461 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5462 gcc_assert (CLASS_TYPE_P (basetype));
5464 if (processing_template_decl)
5466 instance = build_non_dependent_expr (instance);
5467 args = build_non_dependent_args (orig_args);
5470 /* The USER_ARGS are the arguments we will display to users if an
5471 error occurs. The USER_ARGS should not include any
5472 compiler-generated arguments. The "this" pointer hasn't been
5473 added yet. However, we must remove the VTT pointer if this is a
5474 call to a base-class constructor or destructor. */
5476 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5478 /* Callers should explicitly indicate whether they want to construct
5479 the complete object or just the part without virtual bases. */
5480 gcc_assert (name != ctor_identifier);
5481 /* Similarly for destructors. */
5482 gcc_assert (name != dtor_identifier);
5483 /* Remove the VTT pointer, if present. */
5484 if ((name == base_ctor_identifier || name == base_dtor_identifier)
5485 && CLASSTYPE_VBASECLASSES (basetype))
5486 user_args = TREE_CHAIN (user_args);
5489 /* Process the argument list. */
5490 args = resolve_args (args);
5491 if (args == error_mark_node)
5492 return error_mark_node;
5494 instance_ptr = build_this (instance);
5496 /* It's OK to call destructors on cv-qualified objects. Therefore,
5497 convert the INSTANCE_PTR to the unqualified type, if necessary. */
5498 if (DECL_DESTRUCTOR_P (fn))
5500 tree type = build_pointer_type (basetype);
5501 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5502 instance_ptr = build_nop (type, instance_ptr);
5503 name = complete_dtor_identifier;
5506 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5507 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5509 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5510 p = conversion_obstack_alloc (0);
5512 for (fn = fns; fn; fn = OVL_NEXT (fn))
5514 tree t = OVL_CURRENT (fn);
5517 /* We can end up here for copy-init of same or base class. */
5518 if ((flags & LOOKUP_ONLYCONVERTING)
5519 && DECL_NONCONVERTING_P (t))
5522 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5523 this_arglist = mem_args;
5525 this_arglist = args;
5527 if (TREE_CODE (t) == TEMPLATE_DECL)
5528 /* A member template. */
5529 add_template_candidate (&candidates, t,
5532 this_arglist, optype,
5537 else if (! template_only)
5538 add_function_candidate (&candidates, t,
5546 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5549 if (!COMPLETE_TYPE_P (basetype))
5550 cxx_incomplete_type_error (instance_ptr, basetype);
5556 pretty_name = name_as_c_string (name, basetype, &free_p);
5557 error ("no matching function for call to %<%T::%s(%A)%#V%>",
5558 basetype, pretty_name, user_args,
5559 TREE_TYPE (TREE_TYPE (instance_ptr)));
5563 print_z_candidates (candidates);
5564 call = error_mark_node;
5568 cand = tourney (candidates);
5574 pretty_name = name_as_c_string (name, basetype, &free_p);
5575 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
5577 print_z_candidates (candidates);
5580 call = error_mark_node;
5586 if (!(flags & LOOKUP_NONVIRTUAL)
5587 && DECL_PURE_VIRTUAL_P (fn)
5588 && instance == current_class_ref
5589 && (DECL_CONSTRUCTOR_P (current_function_decl)
5590 || DECL_DESTRUCTOR_P (current_function_decl)))
5591 /* This is not an error, it is runtime undefined
5593 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
5594 "abstract virtual %q#D called from constructor"
5595 : "abstract virtual %q#D called from destructor"),
5598 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE
5599 && is_dummy_object (instance_ptr))
5601 error ("cannot call member function %qD without object",
5603 call = error_mark_node;
5607 if (DECL_VINDEX (fn) && ! (flags & LOOKUP_NONVIRTUAL)
5608 && resolves_to_fixed_type_p (instance, 0))
5609 flags |= LOOKUP_NONVIRTUAL;
5610 /* Now we know what function is being called. */
5613 /* Build the actual CALL_EXPR. */
5614 call = build_over_call (cand, flags);
5615 /* In an expression of the form `a->f()' where `f' turns
5616 out to be a static member function, `a' is
5617 none-the-less evaluated. */
5618 if (TREE_CODE (TREE_TYPE (fn)) != METHOD_TYPE
5619 && !is_dummy_object (instance_ptr)
5620 && TREE_SIDE_EFFECTS (instance_ptr))
5621 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5622 instance_ptr, call);
5623 else if (call != error_mark_node
5624 && DECL_DESTRUCTOR_P (cand->fn)
5625 && !VOID_TYPE_P (TREE_TYPE (call)))
5626 /* An explicit call of the form "x->~X()" has type
5627 "void". However, on platforms where destructors
5628 return "this" (i.e., those where
5629 targetm.cxx.cdtor_returns_this is true), such calls
5630 will appear to have a return value of pointer type
5631 to the low-level call machinery. We do not want to
5632 change the low-level machinery, since we want to be
5633 able to optimize "delete f()" on such platforms as
5634 "operator delete(~X(f()))" (rather than generating
5635 "t = f(), ~X(t), operator delete (t)"). */
5636 call = build_nop (void_type_node, call);
5641 if (processing_template_decl && call != error_mark_node)
5642 call = (build_min_non_dep_call_list
5644 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5647 /* Free all the conversions we allocated. */
5648 obstack_free (&conversion_obstack, p);
5653 /* Returns true iff standard conversion sequence ICS1 is a proper
5654 subsequence of ICS2. */
5657 is_subseq (conversion *ics1, conversion *ics2)
5659 /* We can assume that a conversion of the same code
5660 between the same types indicates a subsequence since we only get
5661 here if the types we are converting from are the same. */
5663 while (ics1->kind == ck_rvalue
5664 || ics1->kind == ck_lvalue)
5665 ics1 = ics1->u.next;
5669 while (ics2->kind == ck_rvalue
5670 || ics2->kind == ck_lvalue)
5671 ics2 = ics2->u.next;
5673 if (ics2->kind == ck_user
5674 || ics2->kind == ck_ambig
5675 || ics2->kind == ck_identity)
5676 /* At this point, ICS1 cannot be a proper subsequence of
5677 ICS2. We can get a USER_CONV when we are comparing the
5678 second standard conversion sequence of two user conversion
5682 ics2 = ics2->u.next;
5684 if (ics2->kind == ics1->kind
5685 && same_type_p (ics2->type, ics1->type)
5686 && same_type_p (ics2->u.next->type,
5687 ics1->u.next->type))
5692 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5693 be any _TYPE nodes. */
5696 is_properly_derived_from (tree derived, tree base)
5698 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5699 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5702 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5703 considers every class derived from itself. */
5704 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5705 && DERIVED_FROM_P (base, derived));
5708 /* We build the ICS for an implicit object parameter as a pointer
5709 conversion sequence. However, such a sequence should be compared
5710 as if it were a reference conversion sequence. If ICS is the
5711 implicit conversion sequence for an implicit object parameter,
5712 modify it accordingly. */
5715 maybe_handle_implicit_object (conversion **ics)
5719 /* [over.match.funcs]
5721 For non-static member functions, the type of the
5722 implicit object parameter is "reference to cv X"
5723 where X is the class of which the function is a
5724 member and cv is the cv-qualification on the member
5725 function declaration. */
5726 conversion *t = *ics;
5727 tree reference_type;
5729 /* The `this' parameter is a pointer to a class type. Make the
5730 implicit conversion talk about a reference to that same class
5732 reference_type = TREE_TYPE (t->type);
5733 reference_type = build_reference_type (reference_type);
5735 if (t->kind == ck_qual)
5737 if (t->kind == ck_ptr)
5739 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
5740 t = direct_reference_binding (reference_type, t);
5741 t->rvaluedness_matches_p = 1;
5746 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5747 and return the initial reference binding conversion. Otherwise,
5748 leave *ICS unchanged and return NULL. */
5751 maybe_handle_ref_bind (conversion **ics)
5753 if ((*ics)->kind == ck_ref_bind)
5755 conversion *old_ics = *ics;
5756 *ics = old_ics->u.next;
5757 (*ics)->user_conv_p = old_ics->user_conv_p;
5758 (*ics)->bad_p = old_ics->bad_p;
5765 /* Compare two implicit conversion sequences according to the rules set out in
5766 [over.ics.rank]. Return values:
5768 1: ics1 is better than ics2
5769 -1: ics2 is better than ics1
5770 0: ics1 and ics2 are indistinguishable */
5773 compare_ics (conversion *ics1, conversion *ics2)
5779 tree deref_from_type1 = NULL_TREE;
5780 tree deref_from_type2 = NULL_TREE;
5781 tree deref_to_type1 = NULL_TREE;
5782 tree deref_to_type2 = NULL_TREE;
5783 conversion_rank rank1, rank2;
5785 /* REF_BINDING is nonzero if the result of the conversion sequence
5786 is a reference type. In that case REF_CONV is the reference
5787 binding conversion. */
5788 conversion *ref_conv1;
5789 conversion *ref_conv2;
5791 /* Handle implicit object parameters. */
5792 maybe_handle_implicit_object (&ics1);
5793 maybe_handle_implicit_object (&ics2);
5795 /* Handle reference parameters. */
5796 ref_conv1 = maybe_handle_ref_bind (&ics1);
5797 ref_conv2 = maybe_handle_ref_bind (&ics2);
5801 When comparing the basic forms of implicit conversion sequences (as
5802 defined in _over.best.ics_)
5804 --a standard conversion sequence (_over.ics.scs_) is a better
5805 conversion sequence than a user-defined conversion sequence
5806 or an ellipsis conversion sequence, and
5808 --a user-defined conversion sequence (_over.ics.user_) is a
5809 better conversion sequence than an ellipsis conversion sequence
5810 (_over.ics.ellipsis_). */
5811 rank1 = CONVERSION_RANK (ics1);
5812 rank2 = CONVERSION_RANK (ics2);
5816 else if (rank1 < rank2)
5819 if (rank1 == cr_bad)
5821 /* XXX Isn't this an extension? */
5822 /* Both ICS are bad. We try to make a decision based on what
5823 would have happened if they'd been good. */
5824 if (ics1->user_conv_p > ics2->user_conv_p
5825 || ics1->rank > ics2->rank)
5827 else if (ics1->user_conv_p < ics2->user_conv_p
5828 || ics1->rank < ics2->rank)
5831 /* We couldn't make up our minds; try to figure it out below. */
5834 if (ics1->ellipsis_p)
5835 /* Both conversions are ellipsis conversions. */
5838 /* User-defined conversion sequence U1 is a better conversion sequence
5839 than another user-defined conversion sequence U2 if they contain the
5840 same user-defined conversion operator or constructor and if the sec-
5841 ond standard conversion sequence of U1 is better than the second
5842 standard conversion sequence of U2. */
5844 if (ics1->user_conv_p)
5849 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
5850 if (t1->kind == ck_ambig)
5852 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
5853 if (t2->kind == ck_ambig)
5856 if (t1->cand->fn != t2->cand->fn)
5859 /* We can just fall through here, after setting up
5860 FROM_TYPE1 and FROM_TYPE2. */
5861 from_type1 = t1->type;
5862 from_type2 = t2->type;
5869 /* We're dealing with two standard conversion sequences.
5873 Standard conversion sequence S1 is a better conversion
5874 sequence than standard conversion sequence S2 if
5876 --S1 is a proper subsequence of S2 (comparing the conversion
5877 sequences in the canonical form defined by _over.ics.scs_,
5878 excluding any Lvalue Transformation; the identity
5879 conversion sequence is considered to be a subsequence of
5880 any non-identity conversion sequence */
5883 while (t1->kind != ck_identity)
5885 from_type1 = t1->type;
5888 while (t2->kind != ck_identity)
5890 from_type2 = t2->type;
5893 if (same_type_p (from_type1, from_type2))
5895 if (is_subseq (ics1, ics2))
5897 if (is_subseq (ics2, ics1))
5900 /* Otherwise, one sequence cannot be a subsequence of the other; they
5901 don't start with the same type. This can happen when comparing the
5902 second standard conversion sequence in two user-defined conversion
5909 --the rank of S1 is better than the rank of S2 (by the rules
5912 Standard conversion sequences are ordered by their ranks: an Exact
5913 Match is a better conversion than a Promotion, which is a better
5914 conversion than a Conversion.
5916 Two conversion sequences with the same rank are indistinguishable
5917 unless one of the following rules applies:
5919 --A conversion that is not a conversion of a pointer, or pointer
5920 to member, to bool is better than another conversion that is such
5923 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5924 so that we do not have to check it explicitly. */
5925 if (ics1->rank < ics2->rank)
5927 else if (ics2->rank < ics1->rank)
5930 to_type1 = ics1->type;
5931 to_type2 = ics2->type;
5933 if (TYPE_PTR_P (from_type1)
5934 && TYPE_PTR_P (from_type2)
5935 && TYPE_PTR_P (to_type1)
5936 && TYPE_PTR_P (to_type2))
5938 deref_from_type1 = TREE_TYPE (from_type1);
5939 deref_from_type2 = TREE_TYPE (from_type2);
5940 deref_to_type1 = TREE_TYPE (to_type1);
5941 deref_to_type2 = TREE_TYPE (to_type2);
5943 /* The rules for pointers to members A::* are just like the rules
5944 for pointers A*, except opposite: if B is derived from A then
5945 A::* converts to B::*, not vice versa. For that reason, we
5946 switch the from_ and to_ variables here. */
5947 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5948 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5949 || (TYPE_PTRMEMFUNC_P (from_type1)
5950 && TYPE_PTRMEMFUNC_P (from_type2)
5951 && TYPE_PTRMEMFUNC_P (to_type1)
5952 && TYPE_PTRMEMFUNC_P (to_type2)))
5954 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5955 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5956 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5957 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5960 if (deref_from_type1 != NULL_TREE
5961 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5962 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5964 /* This was one of the pointer or pointer-like conversions.
5968 --If class B is derived directly or indirectly from class A,
5969 conversion of B* to A* is better than conversion of B* to
5970 void*, and conversion of A* to void* is better than
5971 conversion of B* to void*. */
5972 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5973 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5975 if (is_properly_derived_from (deref_from_type1,
5978 else if (is_properly_derived_from (deref_from_type2,
5982 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5983 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5985 if (same_type_p (deref_from_type1, deref_from_type2))
5987 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5989 if (is_properly_derived_from (deref_from_type1,
5993 /* We know that DEREF_TO_TYPE1 is `void' here. */
5994 else if (is_properly_derived_from (deref_from_type1,
5999 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
6000 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
6004 --If class B is derived directly or indirectly from class A
6005 and class C is derived directly or indirectly from B,
6007 --conversion of C* to B* is better than conversion of C* to
6010 --conversion of B* to A* is better than conversion of C* to
6012 if (same_type_p (deref_from_type1, deref_from_type2))
6014 if (is_properly_derived_from (deref_to_type1,
6017 else if (is_properly_derived_from (deref_to_type2,
6021 else if (same_type_p (deref_to_type1, deref_to_type2))
6023 if (is_properly_derived_from (deref_from_type2,
6026 else if (is_properly_derived_from (deref_from_type1,
6032 else if (CLASS_TYPE_P (non_reference (from_type1))
6033 && same_type_p (from_type1, from_type2))
6035 tree from = non_reference (from_type1);
6039 --binding of an expression of type C to a reference of type
6040 B& is better than binding an expression of type C to a
6041 reference of type A&
6043 --conversion of C to B is better than conversion of C to A, */
6044 if (is_properly_derived_from (from, to_type1)
6045 && is_properly_derived_from (from, to_type2))
6047 if (is_properly_derived_from (to_type1, to_type2))
6049 else if (is_properly_derived_from (to_type2, to_type1))
6053 else if (CLASS_TYPE_P (non_reference (to_type1))
6054 && same_type_p (to_type1, to_type2))
6056 tree to = non_reference (to_type1);
6060 --binding of an expression of type B to a reference of type
6061 A& is better than binding an expression of type C to a
6062 reference of type A&,
6064 --conversion of B to A is better than conversion of C to A */
6065 if (is_properly_derived_from (from_type1, to)
6066 && is_properly_derived_from (from_type2, to))
6068 if (is_properly_derived_from (from_type2, from_type1))
6070 else if (is_properly_derived_from (from_type1, from_type2))
6077 --S1 and S2 differ only in their qualification conversion and yield
6078 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6079 qualification signature of type T1 is a proper subset of the cv-
6080 qualification signature of type T2 */
6081 if (ics1->kind == ck_qual
6082 && ics2->kind == ck_qual
6083 && same_type_p (from_type1, from_type2))
6084 return comp_cv_qual_signature (to_type1, to_type2);
6088 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6089 to an implicit object parameter, and either S1 binds an lvalue reference
6090 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6091 reference to an rvalue and S2 binds an lvalue reference
6092 (C++0x draft standard, 13.3.3.2)
6094 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6095 types to which the references refer are the same type except for
6096 top-level cv-qualifiers, and the type to which the reference
6097 initialized by S2 refers is more cv-qualified than the type to
6098 which the reference initialized by S1 refers */
6100 if (ref_conv1 && ref_conv2
6101 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
6103 if (ref_conv1->rvaluedness_matches_p
6104 && !ref_conv2->rvaluedness_matches_p)
6106 else if (!ref_conv1->rvaluedness_matches_p
6107 && ref_conv2->rvaluedness_matches_p)
6110 return comp_cv_qualification (TREE_TYPE (ref_conv2->type),
6111 TREE_TYPE (ref_conv1->type));
6114 /* Neither conversion sequence is better than the other. */
6118 /* The source type for this standard conversion sequence. */
6121 source_type (conversion *t)
6123 for (;; t = t->u.next)
6125 if (t->kind == ck_user
6126 || t->kind == ck_ambig
6127 || t->kind == ck_identity)
6133 /* Note a warning about preferring WINNER to LOSER. We do this by storing
6134 a pointer to LOSER and re-running joust to produce the warning if WINNER
6135 is actually used. */
6138 add_warning (struct z_candidate *winner, struct z_candidate *loser)
6140 candidate_warning *cw = (candidate_warning *)
6141 conversion_obstack_alloc (sizeof (candidate_warning));
6143 cw->next = winner->warnings;
6144 winner->warnings = cw;
6147 /* Compare two candidates for overloading as described in
6148 [over.match.best]. Return values:
6150 1: cand1 is better than cand2
6151 -1: cand2 is better than cand1
6152 0: cand1 and cand2 are indistinguishable */
6155 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
6158 int off1 = 0, off2 = 0;
6162 /* Candidates that involve bad conversions are always worse than those
6164 if (cand1->viable > cand2->viable)
6166 if (cand1->viable < cand2->viable)
6169 /* If we have two pseudo-candidates for conversions to the same type,
6170 or two candidates for the same function, arbitrarily pick one. */
6171 if (cand1->fn == cand2->fn
6172 && (IS_TYPE_OR_DECL_P (cand1->fn)))
6175 /* a viable function F1
6176 is defined to be a better function than another viable function F2 if
6177 for all arguments i, ICSi(F1) is not a worse conversion sequence than
6178 ICSi(F2), and then */
6180 /* for some argument j, ICSj(F1) is a better conversion sequence than
6183 /* For comparing static and non-static member functions, we ignore
6184 the implicit object parameter of the non-static function. The
6185 standard says to pretend that the static function has an object
6186 parm, but that won't work with operator overloading. */
6187 len = cand1->num_convs;
6188 if (len != cand2->num_convs)
6190 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
6191 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
6193 gcc_assert (static_1 != static_2);
6204 for (i = 0; i < len; ++i)
6206 conversion *t1 = cand1->convs[i + off1];
6207 conversion *t2 = cand2->convs[i + off2];
6208 int comp = compare_ics (t1, t2);
6213 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6214 == cr_std + cr_promotion)
6215 && t1->kind == ck_std
6216 && t2->kind == ck_std
6217 && TREE_CODE (t1->type) == INTEGER_TYPE
6218 && TREE_CODE (t2->type) == INTEGER_TYPE
6219 && (TYPE_PRECISION (t1->type)
6220 == TYPE_PRECISION (t2->type))
6221 && (TYPE_UNSIGNED (t1->u.next->type)
6222 || (TREE_CODE (t1->u.next->type)
6225 tree type = t1->u.next->type;
6227 struct z_candidate *w, *l;
6229 type1 = t1->type, type2 = t2->type,
6230 w = cand1, l = cand2;
6232 type1 = t2->type, type2 = t1->type,
6233 w = cand2, l = cand1;
6237 warning (OPT_Wsign_promo, "passing %qT chooses %qT over %qT",
6238 type, type1, type2);
6239 warning (OPT_Wsign_promo, " in call to %qD", w->fn);
6245 if (winner && comp != winner)
6254 /* warn about confusing overload resolution for user-defined conversions,
6255 either between a constructor and a conversion op, or between two
6257 if (winner && warn_conversion && cand1->second_conv
6258 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6259 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6261 struct z_candidate *w, *l;
6262 bool give_warning = false;
6265 w = cand1, l = cand2;
6267 w = cand2, l = cand1;
6269 /* We don't want to complain about `X::operator T1 ()'
6270 beating `X::operator T2 () const', when T2 is a no less
6271 cv-qualified version of T1. */
6272 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6273 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6275 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6276 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6278 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6283 if (!comp_ptr_ttypes (t, f))
6284 give_warning = true;
6287 give_warning = true;
6293 tree source = source_type (w->convs[0]);
6294 if (! DECL_CONSTRUCTOR_P (w->fn))
6295 source = TREE_TYPE (source);
6296 warning (OPT_Wconversion, "choosing %qD over %qD", w->fn, l->fn);
6297 warning (OPT_Wconversion, " for conversion from %qT to %qT",
6298 source, w->second_conv->type);
6299 inform (" because conversion sequence for the argument is better");
6309 F1 is a non-template function and F2 is a template function
6312 if (!cand1->template_decl && cand2->template_decl)
6314 else if (cand1->template_decl && !cand2->template_decl)
6318 F1 and F2 are template functions and the function template for F1 is
6319 more specialized than the template for F2 according to the partial
6322 if (cand1->template_decl && cand2->template_decl)
6324 winner = more_specialized_fn
6325 (TI_TEMPLATE (cand1->template_decl),
6326 TI_TEMPLATE (cand2->template_decl),
6327 /* [temp.func.order]: The presence of unused ellipsis and default
6328 arguments has no effect on the partial ordering of function
6329 templates. add_function_candidate() will not have
6330 counted the "this" argument for constructors. */
6331 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6337 the context is an initialization by user-defined conversion (see
6338 _dcl.init_ and _over.match.user_) and the standard conversion
6339 sequence from the return type of F1 to the destination type (i.e.,
6340 the type of the entity being initialized) is a better conversion
6341 sequence than the standard conversion sequence from the return type
6342 of F2 to the destination type. */
6344 if (cand1->second_conv)
6346 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6351 /* Check whether we can discard a builtin candidate, either because we
6352 have two identical ones or matching builtin and non-builtin candidates.
6354 (Pedantically in the latter case the builtin which matched the user
6355 function should not be added to the overload set, but we spot it here.
6358 ... the builtin candidates include ...
6359 - do not have the same parameter type list as any non-template
6360 non-member candidate. */
6362 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6363 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6365 for (i = 0; i < len; ++i)
6366 if (!same_type_p (cand1->convs[i]->type,
6367 cand2->convs[i]->type))
6369 if (i == cand1->num_convs)
6371 if (cand1->fn == cand2->fn)
6372 /* Two built-in candidates; arbitrarily pick one. */
6374 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6375 /* cand1 is built-in; prefer cand2. */
6378 /* cand2 is built-in; prefer cand1. */
6383 /* If the two functions are the same (this can happen with declarations
6384 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6385 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6386 && equal_functions (cand1->fn, cand2->fn))
6391 /* Extension: If the worst conversion for one candidate is worse than the
6392 worst conversion for the other, take the first. */
6395 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6396 struct z_candidate *w = 0, *l = 0;
6398 for (i = 0; i < len; ++i)
6400 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6401 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6402 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6403 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6406 winner = 1, w = cand1, l = cand2;
6408 winner = -1, w = cand2, l = cand1;
6414 ISO C++ says that these are ambiguous, even \
6415 though the worst conversion for the first is better than \
6416 the worst conversion for the second:");
6417 print_z_candidate (_("candidate 1:"), w);
6418 print_z_candidate (_("candidate 2:"), l);
6426 gcc_assert (!winner);
6430 /* Given a list of candidates for overloading, find the best one, if any.
6431 This algorithm has a worst case of O(2n) (winner is last), and a best
6432 case of O(n/2) (totally ambiguous); much better than a sorting
6435 static struct z_candidate *
6436 tourney (struct z_candidate *candidates)
6438 struct z_candidate *champ = candidates, *challenger;
6440 int champ_compared_to_predecessor = 0;
6442 /* Walk through the list once, comparing each current champ to the next
6443 candidate, knocking out a candidate or two with each comparison. */
6445 for (challenger = champ->next; challenger; )
6447 fate = joust (champ, challenger, 0);
6449 challenger = challenger->next;
6454 champ = challenger->next;
6457 champ_compared_to_predecessor = 0;
6462 champ_compared_to_predecessor = 1;
6465 challenger = champ->next;
6469 /* Make sure the champ is better than all the candidates it hasn't yet
6470 been compared to. */
6472 for (challenger = candidates;
6474 && !(champ_compared_to_predecessor && challenger->next == champ);
6475 challenger = challenger->next)
6477 fate = joust (champ, challenger, 0);
6485 /* Returns nonzero if things of type FROM can be converted to TO. */
6488 can_convert (tree to, tree from)
6490 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6493 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6496 can_convert_arg (tree to, tree from, tree arg, int flags)
6502 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6503 p = conversion_obstack_alloc (0);
6505 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6507 ok_p = (t && !t->bad_p);
6509 /* Free all the conversions we allocated. */
6510 obstack_free (&conversion_obstack, p);
6515 /* Like can_convert_arg, but allows dubious conversions as well. */
6518 can_convert_arg_bad (tree to, tree from, tree arg)
6523 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6524 p = conversion_obstack_alloc (0);
6525 /* Try to perform the conversion. */
6526 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6528 /* Free all the conversions we allocated. */
6529 obstack_free (&conversion_obstack, p);
6534 /* Convert EXPR to TYPE. Return the converted expression.
6536 Note that we allow bad conversions here because by the time we get to
6537 this point we are committed to doing the conversion. If we end up
6538 doing a bad conversion, convert_like will complain. */
6541 perform_implicit_conversion (tree type, tree expr)
6546 if (error_operand_p (expr))
6547 return error_mark_node;
6549 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6550 p = conversion_obstack_alloc (0);
6552 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6557 error ("could not convert %qE to %qT", expr, type);
6558 expr = error_mark_node;
6560 else if (processing_template_decl)
6562 /* In a template, we are only concerned about determining the
6563 type of non-dependent expressions, so we do not have to
6564 perform the actual conversion. */
6565 if (TREE_TYPE (expr) != type)
6566 expr = build_nop (type, expr);
6569 expr = convert_like (conv, expr);
6571 /* Free all the conversions we allocated. */
6572 obstack_free (&conversion_obstack, p);
6577 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6578 permitted. If the conversion is valid, the converted expression is
6579 returned. Otherwise, NULL_TREE is returned, except in the case
6580 that TYPE is a class type; in that case, an error is issued. If
6581 C_CAST_P is true, then this direction initialization is taking
6582 place as part of a static_cast being attempted as part of a C-style
6586 perform_direct_initialization_if_possible (tree type,
6593 if (type == error_mark_node || error_operand_p (expr))
6594 return error_mark_node;
6597 If the destination type is a (possibly cv-qualified) class type:
6599 -- If the initialization is direct-initialization ...,
6600 constructors are considered. ... If no constructor applies, or
6601 the overload resolution is ambiguous, the initialization is
6603 if (CLASS_TYPE_P (type))
6605 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6606 build_tree_list (NULL_TREE, expr),
6607 type, LOOKUP_NORMAL);
6608 return build_cplus_new (type, expr);
6611 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6612 p = conversion_obstack_alloc (0);
6614 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6617 if (!conv || conv->bad_p)
6620 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6621 /*issue_conversion_warnings=*/false,
6624 /* Free all the conversions we allocated. */
6625 obstack_free (&conversion_obstack, p);
6630 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6631 is being bound to a temporary. Create and return a new VAR_DECL
6632 with the indicated TYPE; this variable will store the value to
6633 which the reference is bound. */
6636 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6640 /* Create the variable. */
6641 var = create_temporary_var (type);
6643 /* Register the variable. */
6644 if (TREE_STATIC (decl))
6646 /* Namespace-scope or local static; give it a mangled name. */
6649 TREE_STATIC (var) = 1;
6650 name = mangle_ref_init_variable (decl);
6651 DECL_NAME (var) = name;
6652 SET_DECL_ASSEMBLER_NAME (var, name);
6653 var = pushdecl_top_level (var);
6656 /* Create a new cleanup level if necessary. */
6657 maybe_push_cleanup_level (type);
6662 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6663 initializing a variable of that TYPE. If DECL is non-NULL, it is
6664 the VAR_DECL being initialized with the EXPR. (In that case, the
6665 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6666 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6667 return, if *CLEANUP is no longer NULL, it will be an expression
6668 that should be pushed as a cleanup after the returned expression
6669 is used to initialize DECL.
6671 Return the converted expression. */
6674 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6679 if (type == error_mark_node || error_operand_p (expr))
6680 return error_mark_node;
6682 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6683 p = conversion_obstack_alloc (0);
6685 conv = reference_binding (type, TREE_TYPE (expr), expr, /*c_cast_p=*/false,
6687 if (!conv || conv->bad_p)
6689 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6690 && !real_lvalue_p (expr))
6691 error ("invalid initialization of non-const reference of "
6692 "type %qT from a temporary of type %qT",
6693 type, TREE_TYPE (expr));
6695 error ("invalid initialization of reference of type "
6696 "%qT from expression of type %qT", type,
6698 return error_mark_node;
6701 /* If DECL is non-NULL, then this special rule applies:
6705 The temporary to which the reference is bound or the temporary
6706 that is the complete object to which the reference is bound
6707 persists for the lifetime of the reference.
6709 The temporaries created during the evaluation of the expression
6710 initializing the reference, except the temporary to which the
6711 reference is bound, are destroyed at the end of the
6712 full-expression in which they are created.
6714 In that case, we store the converted expression into a new
6715 VAR_DECL in a new scope.
6717 However, we want to be careful not to create temporaries when
6718 they are not required. For example, given:
6721 struct D : public B {};
6725 there is no need to copy the return value from "f"; we can just
6726 extend its lifetime. Similarly, given:
6729 struct T { operator S(); };
6733 we can extend the lifetime of the return value of the conversion
6735 gcc_assert (conv->kind == ck_ref_bind);
6739 tree base_conv_type;
6741 /* Skip over the REF_BIND. */
6742 conv = conv->u.next;
6743 /* If the next conversion is a BASE_CONV, skip that too -- but
6744 remember that the conversion was required. */
6745 if (conv->kind == ck_base)
6747 if (conv->check_copy_constructor_p)
6748 check_constructor_callable (TREE_TYPE (expr), expr);
6749 base_conv_type = conv->type;
6750 conv = conv->u.next;
6753 base_conv_type = NULL_TREE;
6754 /* Perform the remainder of the conversion. */
6755 expr = convert_like_real (conv, expr,
6756 /*fn=*/NULL_TREE, /*argnum=*/0,
6758 /*issue_conversion_warnings=*/true,
6759 /*c_cast_p=*/false);
6760 if (error_operand_p (expr))
6761 expr = error_mark_node;
6764 if (!real_lvalue_p (expr))
6769 /* Create the temporary variable. */
6770 type = TREE_TYPE (expr);
6771 var = make_temporary_var_for_ref_to_temp (decl, type);
6772 layout_decl (var, 0);
6773 /* If the rvalue is the result of a function call it will be
6774 a TARGET_EXPR. If it is some other construct (such as a
6775 member access expression where the underlying object is
6776 itself the result of a function call), turn it into a
6777 TARGET_EXPR here. It is important that EXPR be a
6778 TARGET_EXPR below since otherwise the INIT_EXPR will
6779 attempt to make a bitwise copy of EXPR to initialize
6781 if (TREE_CODE (expr) != TARGET_EXPR)
6782 expr = get_target_expr (expr);
6783 /* Create the INIT_EXPR that will initialize the temporary
6785 init = build2 (INIT_EXPR, type, var, expr);
6786 if (at_function_scope_p ())
6788 add_decl_expr (var);
6789 *cleanup = cxx_maybe_build_cleanup (var);
6791 /* We must be careful to destroy the temporary only
6792 after its initialization has taken place. If the
6793 initialization throws an exception, then the
6794 destructor should not be run. We cannot simply
6795 transform INIT into something like:
6797 (INIT, ({ CLEANUP_STMT; }))
6799 because emit_local_var always treats the
6800 initializer as a full-expression. Thus, the
6801 destructor would run too early; it would run at the
6802 end of initializing the reference variable, rather
6803 than at the end of the block enclosing the
6806 The solution is to pass back a cleanup expression
6807 which the caller is responsible for attaching to
6808 the statement tree. */
6812 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
6813 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6814 static_aggregates = tree_cons (NULL_TREE, var,
6817 /* Use its address to initialize the reference variable. */
6818 expr = build_address (var);
6820 expr = convert_to_base (expr,
6821 build_pointer_type (base_conv_type),
6822 /*check_access=*/true,
6824 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6827 /* Take the address of EXPR. */
6828 expr = build_unary_op (ADDR_EXPR, expr, 0);
6829 /* If a BASE_CONV was required, perform it now. */
6831 expr = (perform_implicit_conversion
6832 (build_pointer_type (base_conv_type), expr));
6833 expr = build_nop (type, expr);
6837 /* Perform the conversion. */
6838 expr = convert_like (conv, expr);
6840 /* Free all the conversions we allocated. */
6841 obstack_free (&conversion_obstack, p);
6846 #include "gt-cp-call.h"