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 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com) and
5 modified by Brendan Kehoe (brendan@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
25 /* High-level class interface. */
29 #include "coretypes.h"
38 #include "diagnostic.h"
43 /* The various kinds of conversion. */
45 typedef enum conversion_kind {
59 /* The rank of the conversion. Order of the enumerals matters; better
60 conversions should come earlier in the list. */
62 typedef enum conversion_rank {
73 /* An implicit conversion sequence, in the sense of [over.best.ics].
74 The first conversion to be performed is at the end of the chain.
75 That conversion is always a cr_identity conversion. */
77 typedef struct conversion conversion;
79 /* The kind of conversion represented by this step. */
81 /* The rank of this conversion. */
83 BOOL_BITFIELD user_conv_p : 1;
84 BOOL_BITFIELD ellipsis_p : 1;
85 BOOL_BITFIELD this_p : 1;
86 BOOL_BITFIELD bad_p : 1;
87 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
88 temporary should be created to hold the result of the
90 BOOL_BITFIELD need_temporary_p : 1;
91 /* If KIND is ck_identity or ck_base_conv, true to indicate that the
92 copy constructor must be accessible, even though it is not being
94 BOOL_BITFIELD check_copy_constructor_p : 1;
95 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
96 from a pointer-to-derived to pointer-to-base is being performed. */
97 BOOL_BITFIELD base_p : 1;
98 /* The type of the expression resulting from the conversion. */
101 /* The next conversion in the chain. Since the conversions are
102 arranged from outermost to innermost, the NEXT conversion will
103 actually be performed before this conversion. This variant is
104 used only when KIND is neither ck_identity nor ck_ambig. */
106 /* The expression at the beginning of the conversion chain. This
107 variant is used only if KIND is ck_identity or ck_ambig. */
110 /* The function candidate corresponding to this conversion
111 sequence. This field is only used if KIND is ck_user. */
112 struct z_candidate *cand;
115 #define CONVERSION_RANK(NODE) \
116 ((NODE)->bad_p ? cr_bad \
117 : (NODE)->ellipsis_p ? cr_ellipsis \
118 : (NODE)->user_conv_p ? cr_user \
121 static struct obstack conversion_obstack;
122 static bool conversion_obstack_initialized;
124 static struct z_candidate * tourney (struct z_candidate *);
125 static int equal_functions (tree, tree);
126 static int joust (struct z_candidate *, struct z_candidate *, bool);
127 static int compare_ics (conversion *, conversion *);
128 static tree build_over_call (struct z_candidate *, int);
129 static tree build_java_interface_fn_ref (tree, tree);
130 #define convert_like(CONV, EXPR) \
131 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
132 /*issue_conversion_warnings=*/true, \
134 #define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
135 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
136 /*issue_conversion_warnings=*/true, \
138 static tree convert_like_real (conversion *, tree, tree, int, int, bool,
140 static void op_error (enum tree_code, enum tree_code, tree, tree,
142 static tree build_object_call (tree, tree);
143 static tree resolve_args (tree);
144 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
145 static void print_z_candidate (const char *, struct z_candidate *);
146 static void print_z_candidates (struct z_candidate *);
147 static tree build_this (tree);
148 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
149 static bool any_strictly_viable (struct z_candidate *);
150 static struct z_candidate *add_template_candidate
151 (struct z_candidate **, tree, tree, tree, tree, tree,
152 tree, tree, int, unification_kind_t);
153 static struct z_candidate *add_template_candidate_real
154 (struct z_candidate **, tree, tree, tree, tree, tree,
155 tree, tree, int, tree, unification_kind_t);
156 static struct z_candidate *add_template_conv_candidate
157 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
158 static void add_builtin_candidates
159 (struct z_candidate **, enum tree_code, enum tree_code,
161 static void add_builtin_candidate
162 (struct z_candidate **, enum tree_code, enum tree_code,
163 tree, tree, tree, tree *, tree *, int);
164 static bool is_complete (tree);
165 static void build_builtin_candidate
166 (struct z_candidate **, tree, tree, tree, tree *, tree *,
168 static struct z_candidate *add_conv_candidate
169 (struct z_candidate **, tree, tree, tree, tree, tree);
170 static struct z_candidate *add_function_candidate
171 (struct z_candidate **, tree, tree, tree, tree, tree, int);
172 static conversion *implicit_conversion (tree, tree, tree, bool, int);
173 static conversion *standard_conversion (tree, tree, tree, bool, int);
174 static conversion *reference_binding (tree, tree, tree, int);
175 static conversion *build_conv (conversion_kind, tree, conversion *);
176 static bool is_subseq (conversion *, conversion *);
177 static tree maybe_handle_ref_bind (conversion **);
178 static void maybe_handle_implicit_object (conversion **);
179 static struct z_candidate *add_candidate
180 (struct z_candidate **, tree, tree, size_t,
181 conversion **, tree, tree, int);
182 static tree source_type (conversion *);
183 static void add_warning (struct z_candidate *, struct z_candidate *);
184 static bool reference_related_p (tree, tree);
185 static bool reference_compatible_p (tree, tree);
186 static conversion *convert_class_to_reference (tree, tree, tree);
187 static conversion *direct_reference_binding (tree, conversion *);
188 static bool promoted_arithmetic_type_p (tree);
189 static conversion *conditional_conversion (tree, tree);
190 static char *name_as_c_string (tree, tree, bool *);
191 static tree call_builtin_trap (void);
192 static tree prep_operand (tree);
193 static void add_candidates (tree, tree, tree, bool, tree, tree,
194 int, struct z_candidate **);
195 static conversion *merge_conversion_sequences (conversion *, conversion *);
196 static bool magic_varargs_p (tree);
197 typedef void (*diagnostic_fn_t) (const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
198 static tree build_temp (tree, tree, int, diagnostic_fn_t *);
199 static void check_constructor_callable (tree, tree);
201 /* Returns nonzero iff the destructor name specified in NAME
202 (a BIT_NOT_EXPR) matches BASETYPE. The operand of NAME can take many
206 check_dtor_name (tree basetype, tree name)
208 name = TREE_OPERAND (name, 0);
210 /* Just accept something we've already complained about. */
211 if (name == error_mark_node)
214 if (TREE_CODE (name) == TYPE_DECL)
215 name = TREE_TYPE (name);
216 else if (TYPE_P (name))
218 else if (TREE_CODE (name) == IDENTIFIER_NODE)
220 if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
221 || (TREE_CODE (basetype) == ENUMERAL_TYPE
222 && name == TYPE_IDENTIFIER (basetype)))
225 name = get_type_value (name);
231 template <class T> struct S { ~S(); };
235 NAME will be a class template. */
236 gcc_assert (DECL_CLASS_TEMPLATE_P (name));
240 if (name && TYPE_MAIN_VARIANT (basetype) == TYPE_MAIN_VARIANT (name))
245 /* We want the address of a function or method. We avoid creating a
246 pointer-to-member function. */
249 build_addr_func (tree function)
251 tree type = TREE_TYPE (function);
253 /* We have to do these by hand to avoid real pointer to member
255 if (TREE_CODE (type) == METHOD_TYPE)
257 if (TREE_CODE (function) == OFFSET_REF)
259 tree object = build_address (TREE_OPERAND (function, 0));
260 return get_member_function_from_ptrfunc (&object,
261 TREE_OPERAND (function, 1));
263 function = build_address (function);
266 function = decay_conversion (function);
271 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
272 POINTER_TYPE to those. Note, pointer to member function types
273 (TYPE_PTRMEMFUNC_P) must be handled by our callers. */
276 build_call (tree function, tree parms)
278 int is_constructor = 0;
285 function = build_addr_func (function);
287 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
289 sorry ("unable to call pointer to member function here");
290 return error_mark_node;
293 fntype = TREE_TYPE (TREE_TYPE (function));
294 result_type = TREE_TYPE (fntype);
296 if (TREE_CODE (function) == ADDR_EXPR
297 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
298 decl = TREE_OPERAND (function, 0);
302 /* We check both the decl and the type; a function may be known not to
303 throw without being declared throw(). */
304 nothrow = ((decl && TREE_NOTHROW (decl))
305 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
307 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
308 current_function_returns_abnormally = 1;
310 if (decl && TREE_DEPRECATED (decl))
311 warn_deprecated_use (decl);
312 require_complete_eh_spec_types (fntype, decl);
314 if (decl && DECL_CONSTRUCTOR_P (decl))
317 if (decl && ! TREE_USED (decl))
319 /* We invoke build_call directly for several library functions.
320 These may have been declared normally if we're building libgcc,
321 so we can't just check DECL_ARTIFICIAL. */
322 gcc_assert (DECL_ARTIFICIAL (decl)
323 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
328 /* Don't pass empty class objects by value. This is useful
329 for tags in STL, which are used to control overload resolution.
330 We don't need to handle other cases of copying empty classes. */
331 if (! decl || ! DECL_BUILT_IN (decl))
332 for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
333 if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
334 && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
336 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
337 TREE_VALUE (tmp) = build2 (COMPOUND_EXPR, TREE_TYPE (t),
338 TREE_VALUE (tmp), t);
341 function = build3 (CALL_EXPR, result_type, function, parms, NULL_TREE);
342 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
343 TREE_NOTHROW (function) = nothrow;
348 /* Build something of the form ptr->method (args)
349 or object.method (args). This can also build
350 calls to constructors, and find friends.
352 Member functions always take their class variable
355 INSTANCE is a class instance.
357 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
359 PARMS help to figure out what that NAME really refers to.
361 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
362 down to the real instance type to use for access checking. We need this
363 information to get protected accesses correct.
365 FLAGS is the logical disjunction of zero or more LOOKUP_
366 flags. See cp-tree.h for more info.
368 If this is all OK, calls build_function_call with the resolved
371 This function must also handle being called to perform
372 initialization, promotion/coercion of arguments, and
373 instantiation of default parameters.
375 Note that NAME may refer to an instance variable name. If
376 `operator()()' is defined for the type of that field, then we return
379 /* New overloading code. */
381 typedef struct z_candidate z_candidate;
383 typedef struct candidate_warning candidate_warning;
384 struct candidate_warning {
386 candidate_warning *next;
390 /* The FUNCTION_DECL that will be called if this candidate is
391 selected by overload resolution. */
393 /* The arguments to use when calling this function. */
395 /* The implicit conversion sequences for each of the arguments to
398 /* The number of implicit conversion sequences. */
400 /* If FN is a user-defined conversion, the standard conversion
401 sequence from the type returned by FN to the desired destination
403 conversion *second_conv;
405 /* If FN is a member function, the binfo indicating the path used to
406 qualify the name of FN at the call site. This path is used to
407 determine whether or not FN is accessible if it is selected by
408 overload resolution. The DECL_CONTEXT of FN will always be a
409 (possibly improper) base of this binfo. */
411 /* If FN is a non-static member function, the binfo indicating the
412 subobject to which the `this' pointer should be converted if FN
413 is selected by overload resolution. The type pointed to the by
414 the `this' pointer must correspond to the most derived class
415 indicated by the CONVERSION_PATH. */
416 tree conversion_path;
418 candidate_warning *warnings;
422 /* Returns true iff T is a null pointer constant in the sense of
426 null_ptr_cst_p (tree t)
430 A null pointer constant is an integral constant expression
431 (_expr.const_) rvalue of integer type that evaluates to zero. */
432 t = integral_constant_value (t);
434 || (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
439 /* Returns nonzero if PARMLIST consists of only default parms and/or
443 sufficient_parms_p (tree parmlist)
445 for (; parmlist && parmlist != void_list_node;
446 parmlist = TREE_CHAIN (parmlist))
447 if (!TREE_PURPOSE (parmlist))
452 /* Allocate N bytes of memory from the conversion obstack. The memory
453 is zeroed before being returned. */
456 conversion_obstack_alloc (size_t n)
459 if (!conversion_obstack_initialized)
461 gcc_obstack_init (&conversion_obstack);
462 conversion_obstack_initialized = true;
464 p = obstack_alloc (&conversion_obstack, n);
469 /* Dynamically allocate a conversion. */
472 alloc_conversion (conversion_kind kind)
475 c = conversion_obstack_alloc (sizeof (conversion));
480 #ifdef ENABLE_CHECKING
482 /* Make sure that all memory on the conversion obstack has been
486 validate_conversion_obstack (void)
488 if (conversion_obstack_initialized)
489 gcc_assert ((obstack_next_free (&conversion_obstack)
490 == obstack_base (&conversion_obstack)));
493 #endif /* ENABLE_CHECKING */
495 /* Dynamically allocate an array of N conversions. */
498 alloc_conversions (size_t n)
500 return conversion_obstack_alloc (n * sizeof (conversion *));
504 build_conv (conversion_kind code, tree type, conversion *from)
507 conversion_rank rank = CONVERSION_RANK (from);
509 /* We can't use buildl1 here because CODE could be USER_CONV, which
510 takes two arguments. In that case, the caller is responsible for
511 filling in the second argument. */
512 t = alloc_conversion (code);
535 t->user_conv_p = (code == ck_user || from->user_conv_p);
536 t->bad_p = from->bad_p;
541 /* Build a representation of the identity conversion from EXPR to
542 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
545 build_identity_conv (tree type, tree expr)
549 c = alloc_conversion (ck_identity);
556 /* Converting from EXPR to TYPE was ambiguous in the sense that there
557 were multiple user-defined conversions to accomplish the job.
558 Build a conversion that indicates that ambiguity. */
561 build_ambiguous_conv (tree type, tree expr)
565 c = alloc_conversion (ck_ambig);
573 strip_top_quals (tree t)
575 if (TREE_CODE (t) == ARRAY_TYPE)
577 return cp_build_qualified_type (t, 0);
580 /* Returns the standard conversion path (see [conv]) from type FROM to type
581 TO, if any. For proper handling of null pointer constants, you must
582 also pass the expression EXPR to convert from. If C_CAST_P is true,
583 this conversion is coming from a C-style cast. */
586 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
589 enum tree_code fcode, tcode;
591 bool fromref = false;
593 to = non_reference (to);
594 if (TREE_CODE (from) == REFERENCE_TYPE)
597 from = TREE_TYPE (from);
599 to = strip_top_quals (to);
600 from = strip_top_quals (from);
602 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
603 && expr && type_unknown_p (expr))
605 expr = instantiate_type (to, expr, tf_conv);
606 if (expr == error_mark_node)
608 from = TREE_TYPE (expr);
611 fcode = TREE_CODE (from);
612 tcode = TREE_CODE (to);
614 conv = build_identity_conv (from, expr);
615 if (fcode == FUNCTION_TYPE)
617 from = build_pointer_type (from);
618 fcode = TREE_CODE (from);
619 conv = build_conv (ck_lvalue, from, conv);
621 else if (fcode == ARRAY_TYPE)
623 from = build_pointer_type (TREE_TYPE (from));
624 fcode = TREE_CODE (from);
625 conv = build_conv (ck_lvalue, from, conv);
627 else if (fromref || (expr && lvalue_p (expr)))
628 conv = build_conv (ck_rvalue, from, conv);
630 /* Allow conversion between `__complex__' data types. */
631 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
633 /* The standard conversion sequence to convert FROM to TO is
634 the standard conversion sequence to perform componentwise
636 conversion *part_conv = standard_conversion
637 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
641 conv = build_conv (part_conv->kind, to, conv);
642 conv->rank = part_conv->rank;
650 if (same_type_p (from, to))
653 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
654 && expr && null_ptr_cst_p (expr))
655 conv = build_conv (ck_std, to, conv);
656 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
657 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
659 /* For backwards brain damage compatibility, allow interconversion of
660 pointers and integers with a pedwarn. */
661 conv = build_conv (ck_std, to, conv);
664 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
666 /* For backwards brain damage compatibility, allow interconversion of
667 enums and integers with a pedwarn. */
668 conv = build_conv (ck_std, to, conv);
671 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
672 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
677 if (tcode == POINTER_TYPE
678 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
681 else if (VOID_TYPE_P (TREE_TYPE (to))
682 && !TYPE_PTRMEM_P (from)
683 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
685 from = build_pointer_type
686 (cp_build_qualified_type (void_type_node,
687 cp_type_quals (TREE_TYPE (from))));
688 conv = build_conv (ck_ptr, from, conv);
690 else if (TYPE_PTRMEM_P (from))
692 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
693 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
695 if (DERIVED_FROM_P (fbase, tbase)
696 && (same_type_ignoring_top_level_qualifiers_p
697 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
698 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
700 from = build_ptrmem_type (tbase,
701 TYPE_PTRMEM_POINTED_TO_TYPE (from));
702 conv = build_conv (ck_pmem, from, conv);
704 else if (!same_type_p (fbase, tbase))
707 else if (IS_AGGR_TYPE (TREE_TYPE (from))
708 && IS_AGGR_TYPE (TREE_TYPE (to))
711 An rvalue of type "pointer to cv D," where D is a
712 class type, can be converted to an rvalue of type
713 "pointer to cv B," where B is a base class (clause
714 _class.derived_) of D. If B is an inaccessible
715 (clause _class.access_) or ambiguous
716 (_class.member.lookup_) base class of D, a program
717 that necessitates this conversion is ill-formed.
718 Therefore, we use DERIVED_FROM_P, and do not check
719 access or uniqueness. */
720 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
723 cp_build_qualified_type (TREE_TYPE (to),
724 cp_type_quals (TREE_TYPE (from)));
725 from = build_pointer_type (from);
726 conv = build_conv (ck_ptr, from, conv);
730 if (tcode == POINTER_TYPE)
732 to_pointee = TREE_TYPE (to);
733 from_pointee = TREE_TYPE (from);
737 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
738 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
741 if (same_type_p (from, to))
743 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
744 /* In a C-style cast, we ignore CV-qualification because we
745 are allowed to perform a static_cast followed by a
747 conv = build_conv (ck_qual, to, conv);
748 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
749 conv = build_conv (ck_qual, to, conv);
750 else if (expr && string_conv_p (to, expr, 0))
751 /* converting from string constant to char *. */
752 conv = build_conv (ck_qual, to, conv);
753 else if (ptr_reasonably_similar (to_pointee, from_pointee))
755 conv = build_conv (ck_ptr, to, conv);
763 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
765 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
766 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
767 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
768 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
770 if (!DERIVED_FROM_P (fbase, tbase)
771 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
772 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
773 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
774 || cp_type_quals (fbase) != cp_type_quals (tbase))
777 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
778 from = build_method_type_directly (from,
780 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
781 from = build_ptrmemfunc_type (build_pointer_type (from));
782 conv = build_conv (ck_pmem, from, conv);
785 else if (tcode == BOOLEAN_TYPE)
789 An rvalue of arithmetic, enumeration, pointer, or pointer to
790 member type can be converted to an rvalue of type bool. */
791 if (ARITHMETIC_TYPE_P (from)
792 || fcode == ENUMERAL_TYPE
793 || fcode == POINTER_TYPE
794 || TYPE_PTR_TO_MEMBER_P (from))
796 conv = build_conv (ck_std, to, conv);
797 if (fcode == POINTER_TYPE
798 || TYPE_PTRMEM_P (from)
799 || (TYPE_PTRMEMFUNC_P (from)
800 && conv->rank < cr_pbool))
801 conv->rank = cr_pbool;
807 /* We don't check for ENUMERAL_TYPE here because there are no standard
808 conversions to enum type. */
809 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
810 || tcode == REAL_TYPE)
812 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
814 conv = build_conv (ck_std, to, conv);
816 /* Give this a better rank if it's a promotion. */
817 if (same_type_p (to, type_promotes_to (from))
818 && conv->u.next->rank <= cr_promotion)
819 conv->rank = cr_promotion;
821 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
822 && vector_types_convertible_p (from, to))
823 return build_conv (ck_std, to, conv);
824 else if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE)
825 && IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
826 && is_properly_derived_from (from, to))
828 if (conv->kind == ck_rvalue)
830 conv = build_conv (ck_base, to, conv);
831 /* The derived-to-base conversion indicates the initialization
832 of a parameter with base type from an object of a derived
833 type. A temporary object is created to hold the result of
835 conv->need_temporary_p = true;
843 /* Returns nonzero if T1 is reference-related to T2. */
846 reference_related_p (tree t1, tree t2)
848 t1 = TYPE_MAIN_VARIANT (t1);
849 t2 = TYPE_MAIN_VARIANT (t2);
853 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
854 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
856 return (same_type_p (t1, t2)
857 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
858 && DERIVED_FROM_P (t1, t2)));
861 /* Returns nonzero if T1 is reference-compatible with T2. */
864 reference_compatible_p (tree t1, tree t2)
868 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
869 reference-related to T2 and cv1 is the same cv-qualification as,
870 or greater cv-qualification than, cv2. */
871 return (reference_related_p (t1, t2)
872 && at_least_as_qualified_p (t1, t2));
875 /* Determine whether or not the EXPR (of class type S) can be
876 converted to T as in [over.match.ref]. */
879 convert_class_to_reference (tree t, tree s, tree expr)
885 struct z_candidate *candidates;
886 struct z_candidate *cand;
889 conversions = lookup_conversions (s);
895 Assuming that "cv1 T" is the underlying type of the reference
896 being initialized, and "cv S" is the type of the initializer
897 expression, with S a class type, the candidate functions are
900 --The conversion functions of S and its base classes are
901 considered. Those that are not hidden within S and yield type
902 "reference to cv2 T2", where "cv1 T" is reference-compatible
903 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
905 The argument list has one argument, which is the initializer
910 /* Conceptually, we should take the address of EXPR and put it in
911 the argument list. Unfortunately, however, that can result in
912 error messages, which we should not issue now because we are just
913 trying to find a conversion operator. Therefore, we use NULL,
914 cast to the appropriate type. */
915 arglist = build_int_cst (build_pointer_type (s), 0);
916 arglist = build_tree_list (NULL_TREE, arglist);
918 reference_type = build_reference_type (t);
922 tree fns = TREE_VALUE (conversions);
924 for (; fns; fns = OVL_NEXT (fns))
926 tree f = OVL_CURRENT (fns);
927 tree t2 = TREE_TYPE (TREE_TYPE (f));
931 /* If this is a template function, try to get an exact
933 if (TREE_CODE (f) == TEMPLATE_DECL)
935 cand = add_template_candidate (&candidates,
941 TREE_PURPOSE (conversions),
947 /* Now, see if the conversion function really returns
948 an lvalue of the appropriate type. From the
949 point of view of unification, simply returning an
950 rvalue of the right type is good enough. */
952 t2 = TREE_TYPE (TREE_TYPE (f));
953 if (TREE_CODE (t2) != REFERENCE_TYPE
954 || !reference_compatible_p (t, TREE_TYPE (t2)))
956 candidates = candidates->next;
961 else if (TREE_CODE (t2) == REFERENCE_TYPE
962 && reference_compatible_p (t, TREE_TYPE (t2)))
963 cand = add_function_candidate (&candidates, f, s, arglist,
965 TREE_PURPOSE (conversions),
970 conversion *identity_conv;
971 /* Build a standard conversion sequence indicating the
972 binding from the reference type returned by the
973 function to the desired REFERENCE_TYPE. */
975 = build_identity_conv (TREE_TYPE (TREE_TYPE
976 (TREE_TYPE (cand->fn))),
979 = (direct_reference_binding
980 (reference_type, identity_conv));
981 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
984 conversions = TREE_CHAIN (conversions);
987 candidates = splice_viable (candidates, pedantic, &any_viable_p);
988 /* If none of the conversion functions worked out, let our caller
993 cand = tourney (candidates);
997 /* Now that we know that this is the function we're going to use fix
998 the dummy first argument. */
999 cand->args = tree_cons (NULL_TREE,
1001 TREE_CHAIN (cand->args));
1003 /* Build a user-defined conversion sequence representing the
1005 conv = build_conv (ck_user,
1006 TREE_TYPE (TREE_TYPE (cand->fn)),
1007 build_identity_conv (TREE_TYPE (expr), expr));
1010 /* Merge it with the standard conversion sequence from the
1011 conversion function's return type to the desired type. */
1012 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1014 if (cand->viable == -1)
1017 return cand->second_conv;
1020 /* A reference of the indicated TYPE is being bound directly to the
1021 expression represented by the implicit conversion sequence CONV.
1022 Return a conversion sequence for this binding. */
1025 direct_reference_binding (tree type, conversion *conv)
1029 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1030 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1032 t = TREE_TYPE (type);
1036 When a parameter of reference type binds directly
1037 (_dcl.init.ref_) to an argument expression, the implicit
1038 conversion sequence is the identity conversion, unless the
1039 argument expression has a type that is a derived class of the
1040 parameter type, in which case the implicit conversion sequence is
1041 a derived-to-base Conversion.
1043 If the parameter binds directly to the result of applying a
1044 conversion function to the argument expression, the implicit
1045 conversion sequence is a user-defined conversion sequence
1046 (_over.ics.user_), with the second standard conversion sequence
1047 either an identity conversion or, if the conversion function
1048 returns an entity of a type that is a derived class of the
1049 parameter type, a derived-to-base conversion. */
1050 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1052 /* Represent the derived-to-base conversion. */
1053 conv = build_conv (ck_base, t, conv);
1054 /* We will actually be binding to the base-class subobject in
1055 the derived class, so we mark this conversion appropriately.
1056 That way, convert_like knows not to generate a temporary. */
1057 conv->need_temporary_p = false;
1059 return build_conv (ck_ref_bind, type, conv);
1062 /* Returns the conversion path from type FROM to reference type TO for
1063 purposes of reference binding. For lvalue binding, either pass a
1064 reference type to FROM or an lvalue expression to EXPR. If the
1065 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1066 the conversion returned. */
1069 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1071 conversion *conv = NULL;
1072 tree to = TREE_TYPE (rto);
1076 cp_lvalue_kind lvalue_p = clk_none;
1078 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1080 expr = instantiate_type (to, expr, tf_none);
1081 if (expr == error_mark_node)
1083 from = TREE_TYPE (expr);
1086 if (TREE_CODE (from) == REFERENCE_TYPE)
1088 /* Anything with reference type is an lvalue. */
1089 lvalue_p = clk_ordinary;
1090 from = TREE_TYPE (from);
1093 lvalue_p = real_lvalue_p (expr);
1095 /* Figure out whether or not the types are reference-related and
1096 reference compatible. We have do do this after stripping
1097 references from FROM. */
1098 related_p = reference_related_p (to, from);
1099 compatible_p = reference_compatible_p (to, from);
1101 if (lvalue_p && compatible_p)
1105 If the initializer expression
1107 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1108 is reference-compatible with "cv2 T2,"
1110 the reference is bound directly to the initializer expression
1112 conv = build_identity_conv (from, expr);
1113 conv = direct_reference_binding (rto, conv);
1114 if ((lvalue_p & clk_bitfield) != 0
1115 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1116 /* For the purposes of overload resolution, we ignore the fact
1117 this expression is a bitfield or packed field. (In particular,
1118 [over.ics.ref] says specifically that a function with a
1119 non-const reference parameter is viable even if the
1120 argument is a bitfield.)
1122 However, when we actually call the function we must create
1123 a temporary to which to bind the reference. If the
1124 reference is volatile, or isn't const, then we cannot make
1125 a temporary, so we just issue an error when the conversion
1127 conv->need_temporary_p = true;
1131 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1135 If the initializer expression
1137 -- has a class type (i.e., T2 is a class type) can be
1138 implicitly converted to an lvalue of type "cv3 T3," where
1139 "cv1 T1" is reference-compatible with "cv3 T3". (this
1140 conversion is selected by enumerating the applicable
1141 conversion functions (_over.match.ref_) and choosing the
1142 best one through overload resolution. (_over.match_).
1144 the reference is bound to the lvalue result of the conversion
1145 in the second case. */
1146 conv = convert_class_to_reference (to, from, expr);
1151 /* From this point on, we conceptually need temporaries, even if we
1152 elide them. Only the cases above are "direct bindings". */
1153 if (flags & LOOKUP_NO_TEMP_BIND)
1158 When a parameter of reference type is not bound directly to an
1159 argument expression, the conversion sequence is the one required
1160 to convert the argument expression to the underlying type of the
1161 reference according to _over.best.ics_. Conceptually, this
1162 conversion sequence corresponds to copy-initializing a temporary
1163 of the underlying type with the argument expression. Any
1164 difference in top-level cv-qualification is subsumed by the
1165 initialization itself and does not constitute a conversion. */
1169 Otherwise, the reference shall be to a non-volatile const type. */
1170 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1175 If the initializer expression is an rvalue, with T2 a class type,
1176 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1177 is bound in one of the following ways:
1179 -- The reference is bound to the object represented by the rvalue
1180 or to a sub-object within that object.
1184 We use the first alternative. The implicit conversion sequence
1185 is supposed to be same as we would obtain by generating a
1186 temporary. Fortunately, if the types are reference compatible,
1187 then this is either an identity conversion or the derived-to-base
1188 conversion, just as for direct binding. */
1189 if (CLASS_TYPE_P (from) && compatible_p)
1191 conv = build_identity_conv (from, expr);
1192 conv = direct_reference_binding (rto, conv);
1193 if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
1194 conv->u.next->check_copy_constructor_p = true;
1200 Otherwise, a temporary of type "cv1 T1" is created and
1201 initialized from the initializer expression using the rules for a
1202 non-reference copy initialization. If T1 is reference-related to
1203 T2, cv1 must be the same cv-qualification as, or greater
1204 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1205 if (related_p && !at_least_as_qualified_p (to, from))
1208 conv = implicit_conversion (to, from, expr, /*c_cast_p=*/false,
1213 conv = build_conv (ck_ref_bind, rto, conv);
1214 /* This reference binding, unlike those above, requires the
1215 creation of a temporary. */
1216 conv->need_temporary_p = true;
1221 /* Returns the implicit conversion sequence (see [over.ics]) from type
1222 FROM to type TO. The optional expression EXPR may affect the
1223 conversion. FLAGS are the usual overloading flags. Only
1224 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1225 conversion is coming from a C-style cast. */
1228 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1233 if (from == error_mark_node || to == error_mark_node
1234 || expr == error_mark_node)
1237 if (TREE_CODE (to) == REFERENCE_TYPE)
1238 conv = reference_binding (to, from, expr, flags);
1240 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1245 if (expr != NULL_TREE
1246 && (IS_AGGR_TYPE (from)
1247 || IS_AGGR_TYPE (to))
1248 && (flags & LOOKUP_NO_CONVERSION) == 0)
1250 struct z_candidate *cand;
1252 cand = build_user_type_conversion_1
1253 (to, expr, LOOKUP_ONLYCONVERTING);
1255 conv = cand->second_conv;
1257 /* We used to try to bind a reference to a temporary here, but that
1258 is now handled by the recursive call to this function at the end
1259 of reference_binding. */
1266 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1269 static struct z_candidate *
1270 add_candidate (struct z_candidate **candidates,
1272 size_t num_convs, conversion **convs,
1273 tree access_path, tree conversion_path,
1276 struct z_candidate *cand
1277 = conversion_obstack_alloc (sizeof (struct z_candidate));
1281 cand->convs = convs;
1282 cand->num_convs = num_convs;
1283 cand->access_path = access_path;
1284 cand->conversion_path = conversion_path;
1285 cand->viable = viable;
1286 cand->next = *candidates;
1292 /* Create an overload candidate for the function or method FN called with
1293 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1294 to implicit_conversion.
1296 CTYPE, if non-NULL, is the type we want to pretend this function
1297 comes from for purposes of overload resolution. */
1299 static struct z_candidate *
1300 add_function_candidate (struct z_candidate **candidates,
1301 tree fn, tree ctype, tree arglist,
1302 tree access_path, tree conversion_path,
1305 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1308 tree parmnode, argnode;
1312 /* Built-in functions that haven't been declared don't really
1314 if (DECL_ANTICIPATED (fn))
1317 /* The `this', `in_chrg' and VTT arguments to constructors are not
1318 considered in overload resolution. */
1319 if (DECL_CONSTRUCTOR_P (fn))
1321 parmlist = skip_artificial_parms_for (fn, parmlist);
1322 orig_arglist = arglist;
1323 arglist = skip_artificial_parms_for (fn, arglist);
1326 orig_arglist = arglist;
1328 len = list_length (arglist);
1329 convs = alloc_conversions (len);
1331 /* 13.3.2 - Viable functions [over.match.viable]
1332 First, to be a viable function, a candidate function shall have enough
1333 parameters to agree in number with the arguments in the list.
1335 We need to check this first; otherwise, checking the ICSes might cause
1336 us to produce an ill-formed template instantiation. */
1338 parmnode = parmlist;
1339 for (i = 0; i < len; ++i)
1341 if (parmnode == NULL_TREE || parmnode == void_list_node)
1343 parmnode = TREE_CHAIN (parmnode);
1346 if (i < len && parmnode)
1349 /* Make sure there are default args for the rest of the parms. */
1350 else if (!sufficient_parms_p (parmnode))
1356 /* Second, for F to be a viable function, there shall exist for each
1357 argument an implicit conversion sequence that converts that argument
1358 to the corresponding parameter of F. */
1360 parmnode = parmlist;
1363 for (i = 0; i < len; ++i)
1365 tree arg = TREE_VALUE (argnode);
1366 tree argtype = lvalue_type (arg);
1370 if (parmnode == void_list_node)
1373 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1374 && ! DECL_CONSTRUCTOR_P (fn));
1378 tree parmtype = TREE_VALUE (parmnode);
1380 /* The type of the implicit object parameter ('this') for
1381 overload resolution is not always the same as for the
1382 function itself; conversion functions are considered to
1383 be members of the class being converted, and functions
1384 introduced by a using-declaration are considered to be
1385 members of the class that uses them.
1387 Since build_over_call ignores the ICS for the `this'
1388 parameter, we can just change the parm type. */
1389 if (ctype && is_this)
1392 = build_qualified_type (ctype,
1393 TYPE_QUALS (TREE_TYPE (parmtype)));
1394 parmtype = build_pointer_type (parmtype);
1397 t = implicit_conversion (parmtype, argtype, arg,
1398 /*c_cast_p=*/false, flags);
1402 t = build_identity_conv (argtype, arg);
1403 t->ellipsis_p = true;
1420 parmnode = TREE_CHAIN (parmnode);
1421 argnode = TREE_CHAIN (argnode);
1425 return add_candidate (candidates, fn, orig_arglist, len, convs,
1426 access_path, conversion_path, viable);
1429 /* Create an overload candidate for the conversion function FN which will
1430 be invoked for expression OBJ, producing a pointer-to-function which
1431 will in turn be called with the argument list ARGLIST, and add it to
1432 CANDIDATES. FLAGS is passed on to implicit_conversion.
1434 Actually, we don't really care about FN; we care about the type it
1435 converts to. There may be multiple conversion functions that will
1436 convert to that type, and we rely on build_user_type_conversion_1 to
1437 choose the best one; so when we create our candidate, we record the type
1438 instead of the function. */
1440 static struct z_candidate *
1441 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1442 tree arglist, tree access_path, tree conversion_path)
1444 tree totype = TREE_TYPE (TREE_TYPE (fn));
1445 int i, len, viable, flags;
1446 tree parmlist, parmnode, argnode;
1449 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1450 parmlist = TREE_TYPE (parmlist);
1451 parmlist = TYPE_ARG_TYPES (parmlist);
1453 len = list_length (arglist) + 1;
1454 convs = alloc_conversions (len);
1455 parmnode = parmlist;
1458 flags = LOOKUP_NORMAL;
1460 /* Don't bother looking up the same type twice. */
1461 if (*candidates && (*candidates)->fn == totype)
1464 for (i = 0; i < len; ++i)
1466 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1467 tree argtype = lvalue_type (arg);
1471 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1473 else if (parmnode == void_list_node)
1476 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1477 /*c_cast_p=*/false, flags);
1480 t = build_identity_conv (argtype, arg);
1481 t->ellipsis_p = true;
1495 parmnode = TREE_CHAIN (parmnode);
1496 argnode = TREE_CHAIN (argnode);
1502 if (!sufficient_parms_p (parmnode))
1505 return add_candidate (candidates, totype, arglist, len, convs,
1506 access_path, conversion_path, viable);
1510 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1511 tree type1, tree type2, tree *args, tree *argtypes,
1523 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1524 convs = alloc_conversions (num_convs);
1526 for (i = 0; i < 2; ++i)
1531 t = implicit_conversion (types[i], argtypes[i], args[i],
1532 /*c_cast_p=*/false, flags);
1536 /* We need something for printing the candidate. */
1537 t = build_identity_conv (types[i], NULL_TREE);
1544 /* For COND_EXPR we rearranged the arguments; undo that now. */
1547 convs[2] = convs[1];
1548 convs[1] = convs[0];
1549 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1550 /*c_cast_p=*/false, flags);
1557 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1559 /*access_path=*/NULL_TREE,
1560 /*conversion_path=*/NULL_TREE,
1565 is_complete (tree t)
1567 return COMPLETE_TYPE_P (complete_type (t));
1570 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1573 promoted_arithmetic_type_p (tree type)
1577 In this section, the term promoted integral type is used to refer
1578 to those integral types which are preserved by integral promotion
1579 (including e.g. int and long but excluding e.g. char).
1580 Similarly, the term promoted arithmetic type refers to promoted
1581 integral types plus floating types. */
1582 return ((INTEGRAL_TYPE_P (type)
1583 && same_type_p (type_promotes_to (type), type))
1584 || TREE_CODE (type) == REAL_TYPE);
1587 /* Create any builtin operator overload candidates for the operator in
1588 question given the converted operand types TYPE1 and TYPE2. The other
1589 args are passed through from add_builtin_candidates to
1590 build_builtin_candidate.
1592 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1593 If CODE is requires candidates operands of the same type of the kind
1594 of which TYPE1 and TYPE2 are, we add both candidates
1595 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1598 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1599 enum tree_code code2, tree fnname, tree type1,
1600 tree type2, tree *args, tree *argtypes, int flags)
1604 case POSTINCREMENT_EXPR:
1605 case POSTDECREMENT_EXPR:
1606 args[1] = integer_zero_node;
1607 type2 = integer_type_node;
1616 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1617 and VQ is either volatile or empty, there exist candidate operator
1618 functions of the form
1619 VQ T& operator++(VQ T&);
1620 T operator++(VQ T&, int);
1621 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1622 type other than bool, and VQ is either volatile or empty, there exist
1623 candidate operator functions of the form
1624 VQ T& operator--(VQ T&);
1625 T operator--(VQ T&, int);
1626 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1627 complete object type, and VQ is either volatile or empty, there exist
1628 candidate operator functions of the form
1629 T*VQ& operator++(T*VQ&);
1630 T*VQ& operator--(T*VQ&);
1631 T* operator++(T*VQ&, int);
1632 T* operator--(T*VQ&, int); */
1634 case POSTDECREMENT_EXPR:
1635 case PREDECREMENT_EXPR:
1636 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1638 case POSTINCREMENT_EXPR:
1639 case PREINCREMENT_EXPR:
1640 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1642 type1 = build_reference_type (type1);
1647 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1648 exist candidate operator functions of the form
1652 8 For every function type T, there exist candidate operator functions of
1654 T& operator*(T*); */
1657 if (TREE_CODE (type1) == POINTER_TYPE
1658 && (TYPE_PTROB_P (type1)
1659 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1663 /* 9 For every type T, there exist candidate operator functions of the form
1666 10For every promoted arithmetic type T, there exist candidate operator
1667 functions of the form
1671 case UNARY_PLUS_EXPR: /* unary + */
1672 if (TREE_CODE (type1) == POINTER_TYPE)
1675 if (ARITHMETIC_TYPE_P (type1))
1679 /* 11For every promoted integral type T, there exist candidate operator
1680 functions of the form
1684 if (INTEGRAL_TYPE_P (type1))
1688 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1689 is the same type as C2 or is a derived class of C2, T is a complete
1690 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1691 there exist candidate operator functions of the form
1692 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1693 where CV12 is the union of CV1 and CV2. */
1696 if (TREE_CODE (type1) == POINTER_TYPE
1697 && TYPE_PTR_TO_MEMBER_P (type2))
1699 tree c1 = TREE_TYPE (type1);
1700 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1702 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1703 && (TYPE_PTRMEMFUNC_P (type2)
1704 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1709 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1710 didate operator functions of the form
1715 bool operator<(L, R);
1716 bool operator>(L, R);
1717 bool operator<=(L, R);
1718 bool operator>=(L, R);
1719 bool operator==(L, R);
1720 bool operator!=(L, R);
1721 where LR is the result of the usual arithmetic conversions between
1724 14For every pair of types T and I, where T is a cv-qualified or cv-
1725 unqualified complete object type and I is a promoted integral type,
1726 there exist candidate operator functions of the form
1727 T* operator+(T*, I);
1728 T& operator[](T*, I);
1729 T* operator-(T*, I);
1730 T* operator+(I, T*);
1731 T& operator[](I, T*);
1733 15For every T, where T is a pointer to complete object type, there exist
1734 candidate operator functions of the form112)
1735 ptrdiff_t operator-(T, T);
1737 16For every pointer or enumeration type T, there exist candidate operator
1738 functions of the form
1739 bool operator<(T, T);
1740 bool operator>(T, T);
1741 bool operator<=(T, T);
1742 bool operator>=(T, T);
1743 bool operator==(T, T);
1744 bool operator!=(T, T);
1746 17For every pointer to member type T, there exist candidate operator
1747 functions of the form
1748 bool operator==(T, T);
1749 bool operator!=(T, T); */
1752 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1754 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1756 type2 = ptrdiff_type_node;
1760 case TRUNC_DIV_EXPR:
1761 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1767 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1768 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1770 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1775 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1787 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1789 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1791 if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
1793 if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
1798 if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
1806 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1809 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1811 type1 = ptrdiff_type_node;
1814 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1816 type2 = ptrdiff_type_node;
1821 /* 18For every pair of promoted integral types L and R, there exist candi-
1822 date operator functions of the form
1829 where LR is the result of the usual arithmetic conversions between
1832 case TRUNC_MOD_EXPR:
1838 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1842 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1843 type, VQ is either volatile or empty, and R is a promoted arithmetic
1844 type, there exist candidate operator functions of the form
1845 VQ L& operator=(VQ L&, R);
1846 VQ L& operator*=(VQ L&, R);
1847 VQ L& operator/=(VQ L&, R);
1848 VQ L& operator+=(VQ L&, R);
1849 VQ L& operator-=(VQ L&, R);
1851 20For every pair T, VQ), where T is any type and VQ is either volatile
1852 or empty, there exist candidate operator functions of the form
1853 T*VQ& operator=(T*VQ&, T*);
1855 21For every pair T, VQ), where T is a pointer to member type and VQ is
1856 either volatile or empty, there exist candidate operator functions of
1858 VQ T& operator=(VQ T&, T);
1860 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1861 unqualified complete object type, VQ is either volatile or empty, and
1862 I is a promoted integral type, there exist candidate operator func-
1864 T*VQ& operator+=(T*VQ&, I);
1865 T*VQ& operator-=(T*VQ&, I);
1867 23For every triple L, VQ, R), where L is an integral or enumeration
1868 type, VQ is either volatile or empty, and R is a promoted integral
1869 type, there exist candidate operator functions of the form
1871 VQ L& operator%=(VQ L&, R);
1872 VQ L& operator<<=(VQ L&, R);
1873 VQ L& operator>>=(VQ L&, R);
1874 VQ L& operator&=(VQ L&, R);
1875 VQ L& operator^=(VQ L&, R);
1876 VQ L& operator|=(VQ L&, R); */
1883 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1885 type2 = ptrdiff_type_node;
1889 case TRUNC_DIV_EXPR:
1890 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1894 case TRUNC_MOD_EXPR:
1900 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1905 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1907 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1908 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1909 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1910 || ((TYPE_PTRMEMFUNC_P (type1)
1911 || TREE_CODE (type1) == POINTER_TYPE)
1912 && null_ptr_cst_p (args[1])))
1922 type1 = build_reference_type (type1);
1928 For every pair of promoted arithmetic types L and R, there
1929 exist candidate operator functions of the form
1931 LR operator?(bool, L, R);
1933 where LR is the result of the usual arithmetic conversions
1934 between types L and R.
1936 For every type T, where T is a pointer or pointer-to-member
1937 type, there exist candidate operator functions of the form T
1938 operator?(bool, T, T); */
1940 if (promoted_arithmetic_type_p (type1)
1941 && promoted_arithmetic_type_p (type2))
1945 /* Otherwise, the types should be pointers. */
1946 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
1947 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
1950 /* We don't check that the two types are the same; the logic
1951 below will actually create two candidates; one in which both
1952 parameter types are TYPE1, and one in which both parameter
1960 /* If we're dealing with two pointer types or two enumeral types,
1961 we need candidates for both of them. */
1962 if (type2 && !same_type_p (type1, type2)
1963 && TREE_CODE (type1) == TREE_CODE (type2)
1964 && (TREE_CODE (type1) == REFERENCE_TYPE
1965 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1966 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1967 || TYPE_PTRMEMFUNC_P (type1)
1968 || IS_AGGR_TYPE (type1)
1969 || TREE_CODE (type1) == ENUMERAL_TYPE))
1971 build_builtin_candidate
1972 (candidates, fnname, type1, type1, args, argtypes, flags);
1973 build_builtin_candidate
1974 (candidates, fnname, type2, type2, args, argtypes, flags);
1978 build_builtin_candidate
1979 (candidates, fnname, type1, type2, args, argtypes, flags);
1983 type_decays_to (tree type)
1985 if (TREE_CODE (type) == ARRAY_TYPE)
1986 return build_pointer_type (TREE_TYPE (type));
1987 if (TREE_CODE (type) == FUNCTION_TYPE)
1988 return build_pointer_type (type);
1992 /* There are three conditions of builtin candidates:
1994 1) bool-taking candidates. These are the same regardless of the input.
1995 2) pointer-pair taking candidates. These are generated for each type
1996 one of the input types converts to.
1997 3) arithmetic candidates. According to the standard, we should generate
1998 all of these, but I'm trying not to...
2000 Here we generate a superset of the possible candidates for this particular
2001 case. That is a subset of the full set the standard defines, plus some
2002 other cases which the standard disallows. add_builtin_candidate will
2003 filter out the invalid set. */
2006 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2007 enum tree_code code2, tree fnname, tree *args,
2012 tree type, argtypes[3];
2013 /* TYPES[i] is the set of possible builtin-operator parameter types
2014 we will consider for the Ith argument. These are represented as
2015 a TREE_LIST; the TREE_VALUE of each node is the potential
2019 for (i = 0; i < 3; ++i)
2022 argtypes[i] = lvalue_type (args[i]);
2024 argtypes[i] = NULL_TREE;
2029 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2030 and VQ is either volatile or empty, there exist candidate operator
2031 functions of the form
2032 VQ T& operator++(VQ T&); */
2034 case POSTINCREMENT_EXPR:
2035 case PREINCREMENT_EXPR:
2036 case POSTDECREMENT_EXPR:
2037 case PREDECREMENT_EXPR:
2042 /* 24There also exist candidate operator functions of the form
2043 bool operator!(bool);
2044 bool operator&&(bool, bool);
2045 bool operator||(bool, bool); */
2047 case TRUTH_NOT_EXPR:
2048 build_builtin_candidate
2049 (candidates, fnname, boolean_type_node,
2050 NULL_TREE, args, argtypes, flags);
2053 case TRUTH_ORIF_EXPR:
2054 case TRUTH_ANDIF_EXPR:
2055 build_builtin_candidate
2056 (candidates, fnname, boolean_type_node,
2057 boolean_type_node, args, argtypes, flags);
2079 types[0] = types[1] = NULL_TREE;
2081 for (i = 0; i < 2; ++i)
2085 else if (IS_AGGR_TYPE (argtypes[i]))
2089 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2092 convs = lookup_conversions (argtypes[i]);
2094 if (code == COND_EXPR)
2096 if (real_lvalue_p (args[i]))
2097 types[i] = tree_cons
2098 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2100 types[i] = tree_cons
2101 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2107 for (; convs; convs = TREE_CHAIN (convs))
2109 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2112 && (TREE_CODE (type) != REFERENCE_TYPE
2113 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2116 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2117 types[i] = tree_cons (NULL_TREE, type, types[i]);
2119 type = non_reference (type);
2120 if (i != 0 || ! ref1)
2122 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2123 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2124 types[i] = tree_cons (NULL_TREE, type, types[i]);
2125 if (INTEGRAL_TYPE_P (type))
2126 type = type_promotes_to (type);
2129 if (! value_member (type, types[i]))
2130 types[i] = tree_cons (NULL_TREE, type, types[i]);
2135 if (code == COND_EXPR && real_lvalue_p (args[i]))
2136 types[i] = tree_cons
2137 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2138 type = non_reference (argtypes[i]);
2139 if (i != 0 || ! ref1)
2141 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2142 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2143 types[i] = tree_cons (NULL_TREE, type, types[i]);
2144 if (INTEGRAL_TYPE_P (type))
2145 type = type_promotes_to (type);
2147 types[i] = tree_cons (NULL_TREE, type, types[i]);
2151 /* Run through the possible parameter types of both arguments,
2152 creating candidates with those parameter types. */
2153 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2156 for (type = types[1]; type; type = TREE_CHAIN (type))
2157 add_builtin_candidate
2158 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2159 TREE_VALUE (type), args, argtypes, flags);
2161 add_builtin_candidate
2162 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2163 NULL_TREE, args, argtypes, flags);
2170 /* If TMPL can be successfully instantiated as indicated by
2171 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2173 TMPL is the template. EXPLICIT_TARGS are any explicit template
2174 arguments. ARGLIST is the arguments provided at the call-site.
2175 The RETURN_TYPE is the desired type for conversion operators. If
2176 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2177 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2178 add_conv_candidate. */
2180 static struct z_candidate*
2181 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2182 tree ctype, tree explicit_targs, tree arglist,
2183 tree return_type, tree access_path,
2184 tree conversion_path, int flags, tree obj,
2185 unification_kind_t strict)
2187 int ntparms = DECL_NTPARMS (tmpl);
2188 tree targs = make_tree_vec (ntparms);
2189 tree args_without_in_chrg = arglist;
2190 struct z_candidate *cand;
2194 /* We don't do deduction on the in-charge parameter, the VTT
2195 parameter or 'this'. */
2196 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2197 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2199 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2200 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2201 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2202 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2204 i = fn_type_unification (tmpl, explicit_targs, targs,
2205 args_without_in_chrg,
2206 return_type, strict, flags);
2211 fn = instantiate_template (tmpl, targs, tf_none);
2212 if (fn == error_mark_node)
2217 A member function template is never instantiated to perform the
2218 copy of a class object to an object of its class type.
2220 It's a little unclear what this means; the standard explicitly
2221 does allow a template to be used to copy a class. For example,
2226 template <class T> A(const T&);
2229 void g () { A a (f ()); }
2231 the member template will be used to make the copy. The section
2232 quoted above appears in the paragraph that forbids constructors
2233 whose only parameter is (a possibly cv-qualified variant of) the
2234 class type, and a logical interpretation is that the intent was
2235 to forbid the instantiation of member templates which would then
2237 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2239 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2240 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2245 if (obj != NULL_TREE)
2246 /* Aha, this is a conversion function. */
2247 cand = add_conv_candidate (candidates, fn, obj, access_path,
2248 conversion_path, arglist);
2250 cand = add_function_candidate (candidates, fn, ctype,
2251 arglist, access_path,
2252 conversion_path, flags);
2253 if (DECL_TI_TEMPLATE (fn) != tmpl)
2254 /* This situation can occur if a member template of a template
2255 class is specialized. Then, instantiate_template might return
2256 an instantiation of the specialization, in which case the
2257 DECL_TI_TEMPLATE field will point at the original
2258 specialization. For example:
2260 template <class T> struct S { template <class U> void f(U);
2261 template <> void f(int) {}; };
2265 Here, TMPL will be template <class U> S<double>::f(U).
2266 And, instantiate template will give us the specialization
2267 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2268 for this will point at template <class T> template <> S<T>::f(int),
2269 so that we can find the definition. For the purposes of
2270 overload resolution, however, we want the original TMPL. */
2271 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2273 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2279 static struct z_candidate *
2280 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2281 tree explicit_targs, tree arglist, tree return_type,
2282 tree access_path, tree conversion_path, int flags,
2283 unification_kind_t strict)
2286 add_template_candidate_real (candidates, tmpl, ctype,
2287 explicit_targs, arglist, return_type,
2288 access_path, conversion_path,
2289 flags, NULL_TREE, strict);
2293 static struct z_candidate *
2294 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2295 tree obj, tree arglist, tree return_type,
2296 tree access_path, tree conversion_path)
2299 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2300 arglist, return_type, access_path,
2301 conversion_path, 0, obj, DEDUCE_CONV);
2304 /* The CANDS are the set of candidates that were considered for
2305 overload resolution. Return the set of viable candidates. If none
2306 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2307 is true if a candidate should be considered viable only if it is
2310 static struct z_candidate*
2311 splice_viable (struct z_candidate *cands,
2315 struct z_candidate *viable;
2316 struct z_candidate **last_viable;
2317 struct z_candidate **cand;
2320 last_viable = &viable;
2321 *any_viable_p = false;
2326 struct z_candidate *c = *cand;
2327 if (strict_p ? c->viable == 1 : c->viable)
2332 last_viable = &c->next;
2333 *any_viable_p = true;
2339 return viable ? viable : cands;
2343 any_strictly_viable (struct z_candidate *cands)
2345 for (; cands; cands = cands->next)
2346 if (cands->viable == 1)
2351 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2352 words, it is about to become the "this" pointer for a member
2353 function call. Take the address of the object. */
2356 build_this (tree obj)
2358 /* In a template, we are only concerned about the type of the
2359 expression, so we can take a shortcut. */
2360 if (processing_template_decl)
2361 return build_address (obj);
2363 return build_unary_op (ADDR_EXPR, obj, 0);
2366 /* Returns true iff functions are equivalent. Equivalent functions are
2367 not '==' only if one is a function-local extern function or if
2368 both are extern "C". */
2371 equal_functions (tree fn1, tree fn2)
2373 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2374 || DECL_EXTERN_C_FUNCTION_P (fn1))
2375 return decls_match (fn1, fn2);
2379 /* Print information about one overload candidate CANDIDATE. MSGSTR
2380 is the text to print before the candidate itself.
2382 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2383 to have been run through gettext by the caller. This wart makes
2384 life simpler in print_z_candidates and for the translators. */
2387 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2389 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2391 if (candidate->num_convs == 3)
2392 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2393 candidate->convs[0]->type,
2394 candidate->convs[1]->type,
2395 candidate->convs[2]->type);
2396 else if (candidate->num_convs == 2)
2397 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2398 candidate->convs[0]->type,
2399 candidate->convs[1]->type);
2401 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2402 candidate->convs[0]->type);
2404 else if (TYPE_P (candidate->fn))
2405 inform ("%s %T <conversion>", msgstr, candidate->fn);
2406 else if (candidate->viable == -1)
2407 inform ("%s %+#D <near match>", msgstr, candidate->fn);
2409 inform ("%s %+#D", msgstr, candidate->fn);
2413 print_z_candidates (struct z_candidate *candidates)
2416 struct z_candidate *cand1;
2417 struct z_candidate **cand2;
2419 /* There may be duplicates in the set of candidates. We put off
2420 checking this condition as long as possible, since we have no way
2421 to eliminate duplicates from a set of functions in less than n^2
2422 time. Now we are about to emit an error message, so it is more
2423 permissible to go slowly. */
2424 for (cand1 = candidates; cand1; cand1 = cand1->next)
2426 tree fn = cand1->fn;
2427 /* Skip builtin candidates and conversion functions. */
2428 if (TREE_CODE (fn) != FUNCTION_DECL)
2430 cand2 = &cand1->next;
2433 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2434 && equal_functions (fn, (*cand2)->fn))
2435 *cand2 = (*cand2)->next;
2437 cand2 = &(*cand2)->next;
2444 str = _("candidates are:");
2445 print_z_candidate (str, candidates);
2446 if (candidates->next)
2448 /* Indent successive candidates by the width of the translation
2449 of the above string. */
2450 size_t len = gcc_gettext_width (str) + 1;
2451 char *spaces = alloca (len);
2452 memset (spaces, ' ', len-1);
2453 spaces[len - 1] = '\0';
2455 candidates = candidates->next;
2458 print_z_candidate (spaces, candidates);
2459 candidates = candidates->next;
2465 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2466 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2467 the result of the conversion function to convert it to the final
2468 desired type. Merge the two sequences into a single sequence,
2469 and return the merged sequence. */
2472 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2476 gcc_assert (user_seq->kind == ck_user);
2478 /* Find the end of the second conversion sequence. */
2480 while ((*t)->kind != ck_identity)
2481 t = &((*t)->u.next);
2483 /* Replace the identity conversion with the user conversion
2487 /* The entire sequence is a user-conversion sequence. */
2488 std_seq->user_conv_p = true;
2493 /* Returns the best overload candidate to perform the requested
2494 conversion. This function is used for three the overloading situations
2495 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2496 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2497 per [dcl.init.ref], so we ignore temporary bindings. */
2499 static struct z_candidate *
2500 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2502 struct z_candidate *candidates, *cand;
2503 tree fromtype = TREE_TYPE (expr);
2504 tree ctors = NULL_TREE;
2505 tree conv_fns = NULL_TREE;
2506 conversion *conv = NULL;
2507 tree args = NULL_TREE;
2510 /* We represent conversion within a hierarchy using RVALUE_CONV and
2511 BASE_CONV, as specified by [over.best.ics]; these become plain
2512 constructor calls, as specified in [dcl.init]. */
2513 gcc_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2514 || !DERIVED_FROM_P (totype, fromtype));
2516 if (IS_AGGR_TYPE (totype))
2517 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2519 if (IS_AGGR_TYPE (fromtype))
2520 conv_fns = lookup_conversions (fromtype);
2523 flags |= LOOKUP_NO_CONVERSION;
2529 ctors = BASELINK_FUNCTIONS (ctors);
2531 t = build_int_cst (build_pointer_type (totype), 0);
2532 args = build_tree_list (NULL_TREE, expr);
2533 /* We should never try to call the abstract or base constructor
2535 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2536 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2537 args = tree_cons (NULL_TREE, t, args);
2539 for (; ctors; ctors = OVL_NEXT (ctors))
2541 tree ctor = OVL_CURRENT (ctors);
2542 if (DECL_NONCONVERTING_P (ctor))
2545 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2546 cand = add_template_candidate (&candidates, ctor, totype,
2547 NULL_TREE, args, NULL_TREE,
2548 TYPE_BINFO (totype),
2549 TYPE_BINFO (totype),
2553 cand = add_function_candidate (&candidates, ctor, totype,
2554 args, TYPE_BINFO (totype),
2555 TYPE_BINFO (totype),
2559 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2563 args = build_tree_list (NULL_TREE, build_this (expr));
2565 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2568 tree conversion_path = TREE_PURPOSE (conv_fns);
2569 int convflags = LOOKUP_NO_CONVERSION;
2571 /* If we are called to convert to a reference type, we are trying to
2572 find an lvalue binding, so don't even consider temporaries. If
2573 we don't find an lvalue binding, the caller will try again to
2574 look for a temporary binding. */
2575 if (TREE_CODE (totype) == REFERENCE_TYPE)
2576 convflags |= LOOKUP_NO_TEMP_BIND;
2578 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2580 tree fn = OVL_CURRENT (fns);
2582 /* [over.match.funcs] For conversion functions, the function
2583 is considered to be a member of the class of the implicit
2584 object argument for the purpose of defining the type of
2585 the implicit object parameter.
2587 So we pass fromtype as CTYPE to add_*_candidate. */
2589 if (TREE_CODE (fn) == TEMPLATE_DECL)
2590 cand = add_template_candidate (&candidates, fn, fromtype,
2593 TYPE_BINFO (fromtype),
2598 cand = add_function_candidate (&candidates, fn, fromtype,
2600 TYPE_BINFO (fromtype),
2607 = implicit_conversion (totype,
2608 TREE_TYPE (TREE_TYPE (cand->fn)),
2610 /*c_cast_p=*/false, convflags);
2612 cand->second_conv = ics;
2616 else if (candidates->viable == 1 && ics->bad_p)
2622 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2626 cand = tourney (candidates);
2629 if (flags & LOOKUP_COMPLAIN)
2631 error ("conversion from %qT to %qT is ambiguous",
2633 print_z_candidates (candidates);
2636 cand = candidates; /* any one will do */
2637 cand->second_conv = build_ambiguous_conv (totype, expr);
2638 cand->second_conv->user_conv_p = true;
2639 if (!any_strictly_viable (candidates))
2640 cand->second_conv->bad_p = true;
2641 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2642 ambiguous conversion is no worse than another user-defined
2648 /* Build the user conversion sequence. */
2651 (DECL_CONSTRUCTOR_P (cand->fn)
2652 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2653 build_identity_conv (TREE_TYPE (expr), expr));
2656 /* Combine it with the second conversion sequence. */
2657 cand->second_conv = merge_conversion_sequences (conv,
2660 if (cand->viable == -1)
2661 cand->second_conv->bad_p = true;
2667 build_user_type_conversion (tree totype, tree expr, int flags)
2669 struct z_candidate *cand
2670 = build_user_type_conversion_1 (totype, expr, flags);
2674 if (cand->second_conv->kind == ck_ambig)
2675 return error_mark_node;
2676 expr = convert_like (cand->second_conv, expr);
2677 return convert_from_reference (expr);
2682 /* Do any initial processing on the arguments to a function call. */
2685 resolve_args (tree args)
2688 for (t = args; t; t = TREE_CHAIN (t))
2690 tree arg = TREE_VALUE (t);
2692 if (arg == error_mark_node)
2693 return error_mark_node;
2694 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2696 error ("invalid use of void expression");
2697 return error_mark_node;
2703 /* Perform overload resolution on FN, which is called with the ARGS.
2705 Return the candidate function selected by overload resolution, or
2706 NULL if the event that overload resolution failed. In the case
2707 that overload resolution fails, *CANDIDATES will be the set of
2708 candidates considered, and ANY_VIABLE_P will be set to true or
2709 false to indicate whether or not any of the candidates were
2712 The ARGS should already have gone through RESOLVE_ARGS before this
2713 function is called. */
2715 static struct z_candidate *
2716 perform_overload_resolution (tree fn,
2718 struct z_candidate **candidates,
2721 struct z_candidate *cand;
2722 tree explicit_targs = NULL_TREE;
2723 int template_only = 0;
2726 *any_viable_p = true;
2728 /* Check FN and ARGS. */
2729 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2730 || TREE_CODE (fn) == TEMPLATE_DECL
2731 || TREE_CODE (fn) == OVERLOAD
2732 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2733 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2735 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2737 explicit_targs = TREE_OPERAND (fn, 1);
2738 fn = TREE_OPERAND (fn, 0);
2742 /* Add the various candidate functions. */
2743 add_candidates (fn, args, explicit_targs, template_only,
2744 /*conversion_path=*/NULL_TREE,
2745 /*access_path=*/NULL_TREE,
2749 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2753 cand = tourney (*candidates);
2757 /* Return an expression for a call to FN (a namespace-scope function,
2758 or a static member function) with the ARGS. */
2761 build_new_function_call (tree fn, tree args)
2763 struct z_candidate *candidates, *cand;
2768 args = resolve_args (args);
2769 if (args == error_mark_node)
2770 return error_mark_node;
2772 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2773 p = conversion_obstack_alloc (0);
2775 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2779 if (!any_viable_p && candidates && ! candidates->next)
2780 return build_function_call (candidates->fn, args);
2781 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2782 fn = TREE_OPERAND (fn, 0);
2784 error ("no matching function for call to %<%D(%A)%>",
2785 DECL_NAME (OVL_CURRENT (fn)), args);
2787 error ("call of overloaded %<%D(%A)%> is ambiguous",
2788 DECL_NAME (OVL_CURRENT (fn)), args);
2790 print_z_candidates (candidates);
2791 result = error_mark_node;
2794 result = build_over_call (cand, LOOKUP_NORMAL);
2796 /* Free all the conversions we allocated. */
2797 obstack_free (&conversion_obstack, p);
2802 /* Build a call to a global operator new. FNNAME is the name of the
2803 operator (either "operator new" or "operator new[]") and ARGS are
2804 the arguments provided. *SIZE points to the total number of bytes
2805 required by the allocation, and is updated if that is changed here.
2806 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2807 function determines that no cookie should be used, after all,
2808 *COOKIE_SIZE is set to NULL_TREE. */
2811 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2814 struct z_candidate *candidates;
2815 struct z_candidate *cand;
2818 args = tree_cons (NULL_TREE, *size, args);
2819 args = resolve_args (args);
2820 if (args == error_mark_node)
2827 If this lookup fails to find the name, or if the allocated type
2828 is not a class type, the allocation function's name is looked
2829 up in the global scope.
2831 we disregard block-scope declarations of "operator new". */
2832 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
2834 /* Figure out what function is being called. */
2835 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2837 /* If no suitable function could be found, issue an error message
2842 error ("no matching function for call to %<%D(%A)%>",
2843 DECL_NAME (OVL_CURRENT (fns)), args);
2845 error ("call of overloaded %<%D(%A)%> is ambiguous",
2846 DECL_NAME (OVL_CURRENT (fns)), args);
2848 print_z_candidates (candidates);
2849 return error_mark_node;
2852 /* If a cookie is required, add some extra space. Whether
2853 or not a cookie is required cannot be determined until
2854 after we know which function was called. */
2857 bool use_cookie = true;
2858 if (!abi_version_at_least (2))
2860 tree placement = TREE_CHAIN (args);
2861 /* In G++ 3.2, the check was implemented incorrectly; it
2862 looked at the placement expression, rather than the
2863 type of the function. */
2864 if (placement && !TREE_CHAIN (placement)
2865 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2873 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2874 /* Skip the size_t parameter. */
2875 arg_types = TREE_CHAIN (arg_types);
2876 /* Check the remaining parameters (if any). */
2878 && TREE_CHAIN (arg_types) == void_list_node
2879 && same_type_p (TREE_VALUE (arg_types),
2883 /* If we need a cookie, adjust the number of bytes allocated. */
2886 /* Update the total size. */
2887 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2888 /* Update the argument list to reflect the adjusted size. */
2889 TREE_VALUE (args) = *size;
2892 *cookie_size = NULL_TREE;
2895 /* Build the CALL_EXPR. */
2896 return build_over_call (cand, LOOKUP_NORMAL);
2900 build_object_call (tree obj, tree args)
2902 struct z_candidate *candidates = 0, *cand;
2903 tree fns, convs, mem_args = NULL_TREE;
2904 tree type = TREE_TYPE (obj);
2906 tree result = NULL_TREE;
2909 if (TYPE_PTRMEMFUNC_P (type))
2911 /* It's no good looking for an overloaded operator() on a
2912 pointer-to-member-function. */
2913 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2914 return error_mark_node;
2917 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2918 if (fns == error_mark_node)
2919 return error_mark_node;
2921 args = resolve_args (args);
2923 if (args == error_mark_node)
2924 return error_mark_node;
2926 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2927 p = conversion_obstack_alloc (0);
2931 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2932 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2934 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2936 tree fn = OVL_CURRENT (fns);
2937 if (TREE_CODE (fn) == TEMPLATE_DECL)
2938 add_template_candidate (&candidates, fn, base, NULL_TREE,
2939 mem_args, NULL_TREE,
2942 LOOKUP_NORMAL, DEDUCE_CALL);
2944 add_function_candidate
2945 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2946 TYPE_BINFO (type), LOOKUP_NORMAL);
2950 convs = lookup_conversions (type);
2952 for (; convs; convs = TREE_CHAIN (convs))
2954 tree fns = TREE_VALUE (convs);
2955 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2957 if ((TREE_CODE (totype) == POINTER_TYPE
2958 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2959 || (TREE_CODE (totype) == REFERENCE_TYPE
2960 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2961 || (TREE_CODE (totype) == REFERENCE_TYPE
2962 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2963 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2964 for (; fns; fns = OVL_NEXT (fns))
2966 tree fn = OVL_CURRENT (fns);
2967 if (TREE_CODE (fn) == TEMPLATE_DECL)
2968 add_template_conv_candidate
2969 (&candidates, fn, obj, args, totype,
2970 /*access_path=*/NULL_TREE,
2971 /*conversion_path=*/NULL_TREE);
2973 add_conv_candidate (&candidates, fn, obj, args,
2974 /*conversion_path=*/NULL_TREE,
2975 /*access_path=*/NULL_TREE);
2979 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2982 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
2983 print_z_candidates (candidates);
2984 result = error_mark_node;
2988 cand = tourney (candidates);
2991 error ("call of %<(%T) (%A)%> is ambiguous", TREE_TYPE (obj), args);
2992 print_z_candidates (candidates);
2993 result = error_mark_node;
2995 /* Since cand->fn will be a type, not a function, for a conversion
2996 function, we must be careful not to unconditionally look at
2998 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
2999 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3000 result = build_over_call (cand, LOOKUP_NORMAL);
3003 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1);
3004 obj = convert_from_reference (obj);
3005 result = build_function_call (obj, args);
3009 /* Free all the conversions we allocated. */
3010 obstack_free (&conversion_obstack, p);
3016 op_error (enum tree_code code, enum tree_code code2,
3017 tree arg1, tree arg2, tree arg3, const char *problem)
3021 if (code == MODIFY_EXPR)
3022 opname = assignment_operator_name_info[code2].name;
3024 opname = operator_name_info[code].name;
3029 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3030 problem, arg1, arg2, arg3);
3033 case POSTINCREMENT_EXPR:
3034 case POSTDECREMENT_EXPR:
3035 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3039 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3044 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3049 error ("%s for %<operator%s%> in %<%E %s %E%>",
3050 problem, opname, arg1, opname, arg2);
3052 error ("%s for %<operator%s%> in %<%s%E%>",
3053 problem, opname, opname, arg1);
3058 /* Return the implicit conversion sequence that could be used to
3059 convert E1 to E2 in [expr.cond]. */
3062 conditional_conversion (tree e1, tree e2)
3064 tree t1 = non_reference (TREE_TYPE (e1));
3065 tree t2 = non_reference (TREE_TYPE (e2));
3071 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3072 implicitly converted (clause _conv_) to the type "reference to
3073 T2", subject to the constraint that in the conversion the
3074 reference must bind directly (_dcl.init.ref_) to E1. */
3075 if (real_lvalue_p (e2))
3077 conv = implicit_conversion (build_reference_type (t2),
3081 LOOKUP_NO_TEMP_BIND);
3088 If E1 and E2 have class type, and the underlying class types are
3089 the same or one is a base class of the other: E1 can be converted
3090 to match E2 if the class of T2 is the same type as, or a base
3091 class of, the class of T1, and the cv-qualification of T2 is the
3092 same cv-qualification as, or a greater cv-qualification than, the
3093 cv-qualification of T1. If the conversion is applied, E1 is
3094 changed to an rvalue of type T2 that still refers to the original
3095 source class object (or the appropriate subobject thereof). */
3096 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3097 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3099 if (good_base && at_least_as_qualified_p (t2, t1))
3101 conv = build_identity_conv (t1, e1);
3102 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3103 TYPE_MAIN_VARIANT (t2)))
3104 conv = build_conv (ck_base, t2, conv);
3106 conv = build_conv (ck_rvalue, t2, conv);
3115 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3116 converted to the type that expression E2 would have if E2 were
3117 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3118 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3122 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3123 arguments to the conditional expression. */
3126 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3130 tree result = NULL_TREE;
3131 tree result_type = NULL_TREE;
3132 bool lvalue_p = true;
3133 struct z_candidate *candidates = 0;
3134 struct z_candidate *cand;
3137 /* As a G++ extension, the second argument to the conditional can be
3138 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3139 c'.) If the second operand is omitted, make sure it is
3140 calculated only once. */
3144 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3146 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3147 if (real_lvalue_p (arg1))
3148 arg2 = arg1 = stabilize_reference (arg1);
3150 arg2 = arg1 = save_expr (arg1);
3155 The first expr ession is implicitly converted to bool (clause
3157 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3159 /* If something has already gone wrong, just pass that fact up the
3161 if (error_operand_p (arg1)
3162 || error_operand_p (arg2)
3163 || error_operand_p (arg3))
3164 return error_mark_node;
3168 If either the second or the third operand has type (possibly
3169 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3170 array-to-pointer (_conv.array_), and function-to-pointer
3171 (_conv.func_) standard conversions are performed on the second
3172 and third operands. */
3173 arg2_type = TREE_TYPE (arg2);
3174 arg3_type = TREE_TYPE (arg3);
3175 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3177 /* Do the conversions. We don't these for `void' type arguments
3178 since it can't have any effect and since decay_conversion
3179 does not handle that case gracefully. */
3180 if (!VOID_TYPE_P (arg2_type))
3181 arg2 = decay_conversion (arg2);
3182 if (!VOID_TYPE_P (arg3_type))
3183 arg3 = decay_conversion (arg3);
3184 arg2_type = TREE_TYPE (arg2);
3185 arg3_type = TREE_TYPE (arg3);
3189 One of the following shall hold:
3191 --The second or the third operand (but not both) is a
3192 throw-expression (_except.throw_); the result is of the
3193 type of the other and is an rvalue.
3195 --Both the second and the third operands have type void; the
3196 result is of type void and is an rvalue.
3198 We must avoid calling force_rvalue for expressions of type
3199 "void" because it will complain that their value is being
3201 if (TREE_CODE (arg2) == THROW_EXPR
3202 && TREE_CODE (arg3) != THROW_EXPR)
3204 if (!VOID_TYPE_P (arg3_type))
3205 arg3 = force_rvalue (arg3);
3206 arg3_type = TREE_TYPE (arg3);
3207 result_type = arg3_type;
3209 else if (TREE_CODE (arg2) != THROW_EXPR
3210 && TREE_CODE (arg3) == THROW_EXPR)
3212 if (!VOID_TYPE_P (arg2_type))
3213 arg2 = force_rvalue (arg2);
3214 arg2_type = TREE_TYPE (arg2);
3215 result_type = arg2_type;
3217 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3218 result_type = void_type_node;
3221 error ("%qE has type %<void%> and is not a throw-expression",
3222 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3223 return error_mark_node;
3227 goto valid_operands;
3231 Otherwise, if the second and third operand have different types,
3232 and either has (possibly cv-qualified) class type, an attempt is
3233 made to convert each of those operands to the type of the other. */
3234 else if (!same_type_p (arg2_type, arg3_type)
3235 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3240 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3241 p = conversion_obstack_alloc (0);
3243 conv2 = conditional_conversion (arg2, arg3);
3244 conv3 = conditional_conversion (arg3, arg2);
3248 If both can be converted, or one can be converted but the
3249 conversion is ambiguous, the program is ill-formed. If
3250 neither can be converted, the operands are left unchanged and
3251 further checking is performed as described below. If exactly
3252 one conversion is possible, that conversion is applied to the
3253 chosen operand and the converted operand is used in place of
3254 the original operand for the remainder of this section. */
3255 if ((conv2 && !conv2->bad_p
3256 && conv3 && !conv3->bad_p)
3257 || (conv2 && conv2->kind == ck_ambig)
3258 || (conv3 && conv3->kind == ck_ambig))
3260 error ("operands to ?: have different types");
3261 result = error_mark_node;
3263 else if (conv2 && !conv2->bad_p)
3265 arg2 = convert_like (conv2, arg2);
3266 arg2 = convert_from_reference (arg2);
3267 arg2_type = TREE_TYPE (arg2);
3269 else if (conv3 && !conv3->bad_p)
3271 arg3 = convert_like (conv3, arg3);
3272 arg3 = convert_from_reference (arg3);
3273 arg3_type = TREE_TYPE (arg3);
3276 /* Free all the conversions we allocated. */
3277 obstack_free (&conversion_obstack, p);
3282 /* If, after the conversion, both operands have class type,
3283 treat the cv-qualification of both operands as if it were the
3284 union of the cv-qualification of the operands.
3286 The standard is not clear about what to do in this
3287 circumstance. For example, if the first operand has type
3288 "const X" and the second operand has a user-defined
3289 conversion to "volatile X", what is the type of the second
3290 operand after this step? Making it be "const X" (matching
3291 the first operand) seems wrong, as that discards the
3292 qualification without actually performing a copy. Leaving it
3293 as "volatile X" seems wrong as that will result in the
3294 conditional expression failing altogether, even though,
3295 according to this step, the one operand could be converted to
3296 the type of the other. */
3297 if ((conv2 || conv3)
3298 && CLASS_TYPE_P (arg2_type)
3299 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3300 arg2_type = arg3_type =
3301 cp_build_qualified_type (arg2_type,
3302 TYPE_QUALS (arg2_type)
3303 | TYPE_QUALS (arg3_type));
3308 If the second and third operands are lvalues and have the same
3309 type, the result is of that type and is an lvalue. */
3310 if (real_lvalue_p (arg2)
3311 && real_lvalue_p (arg3)
3312 && same_type_p (arg2_type, arg3_type))
3314 result_type = arg2_type;
3315 goto valid_operands;
3320 Otherwise, the result is an rvalue. If the second and third
3321 operand do not have the same type, and either has (possibly
3322 cv-qualified) class type, overload resolution is used to
3323 determine the conversions (if any) to be applied to the operands
3324 (_over.match.oper_, _over.built_). */
3326 if (!same_type_p (arg2_type, arg3_type)
3327 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3333 /* Rearrange the arguments so that add_builtin_candidate only has
3334 to know about two args. In build_builtin_candidates, the
3335 arguments are unscrambled. */
3339 add_builtin_candidates (&candidates,
3342 ansi_opname (COND_EXPR),
3348 If the overload resolution fails, the program is
3350 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3353 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3354 print_z_candidates (candidates);
3355 return error_mark_node;
3357 cand = tourney (candidates);
3360 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3361 print_z_candidates (candidates);
3362 return error_mark_node;
3367 Otherwise, the conversions thus determined are applied, and
3368 the converted operands are used in place of the original
3369 operands for the remainder of this section. */
3370 conv = cand->convs[0];
3371 arg1 = convert_like (conv, arg1);
3372 conv = cand->convs[1];
3373 arg2 = convert_like (conv, arg2);
3374 conv = cand->convs[2];
3375 arg3 = convert_like (conv, arg3);
3380 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3381 and function-to-pointer (_conv.func_) standard conversions are
3382 performed on the second and third operands.
3384 We need to force the lvalue-to-rvalue conversion here for class types,
3385 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3386 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3389 arg2 = force_rvalue (arg2);
3390 if (!CLASS_TYPE_P (arg2_type))
3391 arg2_type = TREE_TYPE (arg2);
3393 arg3 = force_rvalue (arg3);
3394 if (!CLASS_TYPE_P (arg2_type))
3395 arg3_type = TREE_TYPE (arg3);
3397 if (arg2 == error_mark_node || arg3 == error_mark_node)
3398 return error_mark_node;
3402 After those conversions, one of the following shall hold:
3404 --The second and third operands have the same type; the result is of
3406 if (same_type_p (arg2_type, arg3_type))
3407 result_type = arg2_type;
3410 --The second and third operands have arithmetic or enumeration
3411 type; the usual arithmetic conversions are performed to bring
3412 them to a common type, and the result is of that type. */
3413 else if ((ARITHMETIC_TYPE_P (arg2_type)
3414 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3415 && (ARITHMETIC_TYPE_P (arg3_type)
3416 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3418 /* In this case, there is always a common type. */
3419 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3422 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3423 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3424 warning (0, "enumeral mismatch in conditional expression: %qT vs %qT",
3425 arg2_type, arg3_type);
3426 else if (extra_warnings
3427 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3428 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3429 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3430 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3431 warning (0, "enumeral and non-enumeral type in conditional expression");
3433 arg2 = perform_implicit_conversion (result_type, arg2);
3434 arg3 = perform_implicit_conversion (result_type, arg3);
3438 --The second and third operands have pointer type, or one has
3439 pointer type and the other is a null pointer constant; pointer
3440 conversions (_conv.ptr_) and qualification conversions
3441 (_conv.qual_) are performed to bring them to their composite
3442 pointer type (_expr.rel_). The result is of the composite
3445 --The second and third operands have pointer to member type, or
3446 one has pointer to member type and the other is a null pointer
3447 constant; pointer to member conversions (_conv.mem_) and
3448 qualification conversions (_conv.qual_) are performed to bring
3449 them to a common type, whose cv-qualification shall match the
3450 cv-qualification of either the second or the third operand.
3451 The result is of the common type. */
3452 else if ((null_ptr_cst_p (arg2)
3453 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3454 || (null_ptr_cst_p (arg3)
3455 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3456 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3457 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3458 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3460 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3461 arg3, "conditional expression");
3462 if (result_type == error_mark_node)
3463 return error_mark_node;
3464 arg2 = perform_implicit_conversion (result_type, arg2);
3465 arg3 = perform_implicit_conversion (result_type, arg3);
3470 error ("operands to ?: have different types");
3471 return error_mark_node;
3475 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3477 /* We can't use result_type below, as fold might have returned a
3480 /* Expand both sides into the same slot, hopefully the target of the
3481 ?: expression. We used to check for TARGET_EXPRs here, but now we
3482 sometimes wrap them in NOP_EXPRs so the test would fail. */
3483 if (!lvalue_p && CLASS_TYPE_P (TREE_TYPE (result)))
3484 result = get_target_expr (result);
3486 /* If this expression is an rvalue, but might be mistaken for an
3487 lvalue, we must add a NON_LVALUE_EXPR. */
3488 if (!lvalue_p && real_lvalue_p (result))
3489 result = rvalue (result);
3494 /* OPERAND is an operand to an expression. Perform necessary steps
3495 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3499 prep_operand (tree operand)
3503 if (CLASS_TYPE_P (TREE_TYPE (operand))
3504 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3505 /* Make sure the template type is instantiated now. */
3506 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3512 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3513 OVERLOAD) to the CANDIDATES, returning an updated list of
3514 CANDIDATES. The ARGS are the arguments provided to the call,
3515 without any implicit object parameter. The EXPLICIT_TARGS are
3516 explicit template arguments provided. TEMPLATE_ONLY is true if
3517 only template functions should be considered. CONVERSION_PATH,
3518 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3521 add_candidates (tree fns, tree args,
3522 tree explicit_targs, bool template_only,
3523 tree conversion_path, tree access_path,
3525 struct z_candidate **candidates)
3528 tree non_static_args;
3530 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3531 /* Delay creating the implicit this parameter until it is needed. */
3532 non_static_args = NULL_TREE;
3539 fn = OVL_CURRENT (fns);
3540 /* Figure out which set of arguments to use. */
3541 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3543 /* If this function is a non-static member, prepend the implicit
3544 object parameter. */
3545 if (!non_static_args)
3546 non_static_args = tree_cons (NULL_TREE,
3547 build_this (TREE_VALUE (args)),
3549 fn_args = non_static_args;
3552 /* Otherwise, just use the list of arguments provided. */
3555 if (TREE_CODE (fn) == TEMPLATE_DECL)
3556 add_template_candidate (candidates,
3566 else if (!template_only)
3567 add_function_candidate (candidates,
3574 fns = OVL_NEXT (fns);
3579 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3582 struct z_candidate *candidates = 0, *cand;
3583 tree arglist, fnname;
3585 tree result = NULL_TREE;
3586 bool result_valid_p = false;
3587 enum tree_code code2 = NOP_EXPR;
3593 if (error_operand_p (arg1)
3594 || error_operand_p (arg2)
3595 || error_operand_p (arg3))
3596 return error_mark_node;
3598 if (code == MODIFY_EXPR)
3600 code2 = TREE_CODE (arg3);
3602 fnname = ansi_assopname (code2);
3605 fnname = ansi_opname (code);
3607 arg1 = prep_operand (arg1);
3613 case VEC_DELETE_EXPR:
3615 /* Use build_op_new_call and build_op_delete_call instead. */
3619 return build_object_call (arg1, arg2);
3625 arg2 = prep_operand (arg2);
3626 arg3 = prep_operand (arg3);
3628 if (code == COND_EXPR)
3630 if (arg2 == NULL_TREE
3631 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3632 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3633 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3634 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3637 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3638 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3641 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3642 arg2 = integer_zero_node;
3644 arglist = NULL_TREE;
3646 arglist = tree_cons (NULL_TREE, arg3, arglist);
3648 arglist = tree_cons (NULL_TREE, arg2, arglist);
3649 arglist = tree_cons (NULL_TREE, arg1, arglist);
3651 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3652 p = conversion_obstack_alloc (0);
3654 /* Add namespace-scope operators to the list of functions to
3656 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3657 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3658 flags, &candidates);
3659 /* Add class-member operators to the candidate set. */
3660 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3664 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3665 if (fns == error_mark_node)
3667 result = error_mark_node;
3668 goto user_defined_result_ready;
3671 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3673 BASELINK_BINFO (fns),
3674 TYPE_BINFO (TREE_TYPE (arg1)),
3675 flags, &candidates);
3678 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3679 to know about two args; a builtin candidate will always have a first
3680 parameter of type bool. We'll handle that in
3681 build_builtin_candidate. */
3682 if (code == COND_EXPR)
3692 args[2] = NULL_TREE;
3695 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3701 /* For these, the built-in candidates set is empty
3702 [over.match.oper]/3. We don't want non-strict matches
3703 because exact matches are always possible with built-in
3704 operators. The built-in candidate set for COMPONENT_REF
3705 would be empty too, but since there are no such built-in
3706 operators, we accept non-strict matches for them. */
3711 strict_p = pedantic;
3715 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3720 case POSTINCREMENT_EXPR:
3721 case POSTDECREMENT_EXPR:
3722 /* Look for an `operator++ (int)'. If they didn't have
3723 one, then we fall back to the old way of doing things. */
3724 if (flags & LOOKUP_COMPLAIN)
3725 pedwarn ("no %<%D(int)%> declared for postfix %qs, "
3726 "trying prefix operator instead",
3728 operator_name_info[code].name);
3729 if (code == POSTINCREMENT_EXPR)
3730 code = PREINCREMENT_EXPR;
3732 code = PREDECREMENT_EXPR;
3733 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
3737 /* The caller will deal with these. */
3742 result_valid_p = true;
3746 if (flags & LOOKUP_COMPLAIN)
3748 op_error (code, code2, arg1, arg2, arg3, "no match");
3749 print_z_candidates (candidates);
3751 result = error_mark_node;
3757 cand = tourney (candidates);
3760 if (flags & LOOKUP_COMPLAIN)
3762 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3763 print_z_candidates (candidates);
3765 result = error_mark_node;
3767 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3770 *overloaded_p = true;
3772 result = build_over_call (cand, LOOKUP_NORMAL);
3776 /* Give any warnings we noticed during overload resolution. */
3779 struct candidate_warning *w;
3780 for (w = cand->warnings; w; w = w->next)
3781 joust (cand, w->loser, 1);
3784 /* Check for comparison of different enum types. */
3793 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3794 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3795 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3796 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3798 warning (0, "comparison between %q#T and %q#T",
3799 TREE_TYPE (arg1), TREE_TYPE (arg2));
3806 /* We need to strip any leading REF_BIND so that bitfields
3807 don't cause errors. This should not remove any important
3808 conversions, because builtins don't apply to class
3809 objects directly. */
3810 conv = cand->convs[0];
3811 if (conv->kind == ck_ref_bind)
3812 conv = conv->u.next;
3813 arg1 = convert_like (conv, arg1);
3816 conv = cand->convs[1];
3817 if (conv->kind == ck_ref_bind)
3818 conv = conv->u.next;
3819 arg2 = convert_like (conv, arg2);
3823 conv = cand->convs[2];
3824 if (conv->kind == ck_ref_bind)
3825 conv = conv->u.next;
3826 arg3 = convert_like (conv, arg3);
3831 user_defined_result_ready:
3833 /* Free all the conversions we allocated. */
3834 obstack_free (&conversion_obstack, p);
3836 if (result || result_valid_p)
3843 return build_modify_expr (arg1, code2, arg2);
3846 return build_indirect_ref (arg1, "unary *");
3851 case TRUNC_DIV_EXPR:
3862 case TRUNC_MOD_EXPR:
3866 case TRUTH_ANDIF_EXPR:
3867 case TRUTH_ORIF_EXPR:
3868 return cp_build_binary_op (code, arg1, arg2);
3870 case UNARY_PLUS_EXPR:
3873 case TRUTH_NOT_EXPR:
3874 case PREINCREMENT_EXPR:
3875 case POSTINCREMENT_EXPR:
3876 case PREDECREMENT_EXPR:
3877 case POSTDECREMENT_EXPR:
3880 return build_unary_op (code, arg1, candidates != 0);
3883 return build_array_ref (arg1, arg2);
3886 return build_conditional_expr (arg1, arg2, arg3);
3889 return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2);
3891 /* The caller will deal with these. */
3903 /* Build a call to operator delete. This has to be handled very specially,
3904 because the restrictions on what signatures match are different from all
3905 other call instances. For a normal delete, only a delete taking (void *)
3906 or (void *, size_t) is accepted. For a placement delete, only an exact
3907 match with the placement new is accepted.
3909 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3910 ADDR is the pointer to be deleted.
3911 SIZE is the size of the memory block to be deleted.
3912 GLOBAL_P is true if the delete-expression should not consider
3913 class-specific delete operators.
3914 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3917 build_op_delete_call (enum tree_code code, tree addr, tree size,
3918 bool global_p, tree placement)
3920 tree fn = NULL_TREE;
3921 tree fns, fnname, argtypes, args, type;
3924 if (addr == error_mark_node)
3925 return error_mark_node;
3927 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3929 fnname = ansi_opname (code);
3931 if (CLASS_TYPE_P (type)
3932 && COMPLETE_TYPE_P (complete_type (type))
3936 If the result of the lookup is ambiguous or inaccessible, or if
3937 the lookup selects a placement deallocation function, the
3938 program is ill-formed.
3940 Therefore, we ask lookup_fnfields to complain about ambiguity. */
3942 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3943 if (fns == error_mark_node)
3944 return error_mark_node;
3949 if (fns == NULL_TREE)
3950 fns = lookup_name_nonclass (fnname);
3957 /* Find the allocation function that is being called. */
3958 call_expr = placement;
3959 /* Extract the function. */
3960 alloc_fn = get_callee_fndecl (call_expr);
3961 gcc_assert (alloc_fn != NULL_TREE);
3962 /* Then the second parm type. */
3963 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3964 /* Also the second argument. */
3965 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3969 /* First try it without the size argument. */
3970 argtypes = void_list_node;
3974 /* Strip const and volatile from addr. */
3975 addr = cp_convert (ptr_type_node, addr);
3977 /* We make two tries at finding a matching `operator delete'. On
3978 the first pass, we look for a one-operator (or placement)
3979 operator delete. If we're not doing placement delete, then on
3980 the second pass we look for a two-argument delete. */
3981 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
3983 /* Go through the `operator delete' functions looking for one
3984 with a matching type. */
3985 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
3991 /* The first argument must be "void *". */
3992 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
3993 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
3996 /* On the first pass, check the rest of the arguments. */
4002 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4010 /* On the second pass, the second argument must be
4013 && same_type_p (TREE_VALUE (t), sizetype)
4014 && TREE_CHAIN (t) == void_list_node)
4018 /* If we found a match, we're done. */
4023 /* If we have a matching function, call it. */
4026 /* Make sure we have the actual function, and not an
4028 fn = OVL_CURRENT (fn);
4030 /* If the FN is a member function, make sure that it is
4032 if (DECL_CLASS_SCOPE_P (fn))
4033 perform_or_defer_access_check (TYPE_BINFO (type), fn);
4036 args = tree_cons (NULL_TREE, addr, args);
4038 args = tree_cons (NULL_TREE, addr,
4039 build_tree_list (NULL_TREE, size));
4043 /* The placement args might not be suitable for overload
4044 resolution at this point, so build the call directly. */
4046 return build_cxx_call (fn, args);
4049 return build_function_call (fn, args);
4052 /* If we are doing placement delete we do nothing if we don't find a
4053 matching op delete. */
4057 error ("no suitable %<operator %s%> for %qT",
4058 operator_name_info[(int)code].name, type);
4059 return error_mark_node;
4062 /* If the current scope isn't allowed to access DECL along
4063 BASETYPE_PATH, give an error. The most derived class in
4064 BASETYPE_PATH is the one used to qualify DECL. */
4067 enforce_access (tree basetype_path, tree decl)
4069 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4071 if (!accessible_p (basetype_path, decl, true))
4073 if (TREE_PRIVATE (decl))
4074 error ("%q+#D is private", decl);
4075 else if (TREE_PROTECTED (decl))
4076 error ("%q+#D is protected", decl);
4078 error ("%q+#D is inaccessible", decl);
4079 error ("within this context");
4086 /* Check that a callable constructor to initialize a temporary of
4087 TYPE from an EXPR exists. */
4090 check_constructor_callable (tree type, tree expr)
4092 build_special_member_call (NULL_TREE,
4093 complete_ctor_identifier,
4094 build_tree_list (NULL_TREE, expr),
4096 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING
4097 | LOOKUP_NO_CONVERSION
4098 | LOOKUP_CONSTRUCTOR_CALLABLE);
4101 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4102 bitwise or of LOOKUP_* values. If any errors are warnings are
4103 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4104 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4108 build_temp (tree expr, tree type, int flags,
4109 diagnostic_fn_t *diagnostic_fn)
4113 savew = warningcount, savee = errorcount;
4114 expr = build_special_member_call (NULL_TREE,
4115 complete_ctor_identifier,
4116 build_tree_list (NULL_TREE, expr),
4118 if (warningcount > savew)
4119 *diagnostic_fn = warning0;
4120 else if (errorcount > savee)
4121 *diagnostic_fn = error;
4123 *diagnostic_fn = NULL;
4128 /* Perform the conversions in CONVS on the expression EXPR. FN and
4129 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4130 indicates the `this' argument of a method. INNER is nonzero when
4131 being called to continue a conversion chain. It is negative when a
4132 reference binding will be applied, positive otherwise. If
4133 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4134 conversions will be emitted if appropriate. If C_CAST_P is true,
4135 this conversion is coming from a C-style cast; in that case,
4136 conversions to inaccessible bases are permitted. */
4139 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4140 int inner, bool issue_conversion_warnings,
4143 tree totype = convs->type;
4144 diagnostic_fn_t diagnostic_fn;
4147 && convs->kind != ck_user
4148 && convs->kind != ck_ambig
4149 && convs->kind != ck_ref_bind)
4151 conversion *t = convs;
4152 for (; t; t = convs->u.next)
4154 if (t->kind == ck_user || !t->bad_p)
4156 expr = convert_like_real (t, expr, fn, argnum, 1,
4157 /*issue_conversion_warnings=*/false,
4158 /*c_cast_p=*/false);
4161 else if (t->kind == ck_ambig)
4162 return convert_like_real (t, expr, fn, argnum, 1,
4163 /*issue_conversion_warnings=*/false,
4164 /*c_cast_p=*/false);
4165 else if (t->kind == ck_identity)
4168 pedwarn ("invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4170 pedwarn (" initializing argument %P of %qD", argnum, fn);
4171 return cp_convert (totype, expr);
4174 if (issue_conversion_warnings)
4176 tree t = non_reference (totype);
4178 /* Issue warnings about peculiar, but valid, uses of NULL. */
4179 if (ARITHMETIC_TYPE_P (t) && expr == null_node)
4182 warning (0, "passing NULL to non-pointer argument %P of %qD",
4185 warning (0, "converting to non-pointer type %qT from NULL", t);
4188 /* Warn about assigning a floating-point type to an integer type. */
4189 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
4190 && TREE_CODE (t) == INTEGER_TYPE)
4193 warning (0, "passing %qT for argument %P to %qD",
4194 TREE_TYPE (expr), argnum, fn);
4196 warning (0, "converting to %qT from %qT", t, TREE_TYPE (expr));
4198 /* And warn about assigning a negative value to an unsigned
4200 else if (TYPE_UNSIGNED (t) && TREE_CODE (t) != BOOLEAN_TYPE)
4202 if (TREE_CODE (expr) == INTEGER_CST && TREE_NEGATED_INT (expr))
4205 warning (0, "passing negative value %qE for argument %P to %qD",
4208 warning (0, "converting negative value %qE to %qT", expr, t);
4211 overflow_warning (expr);
4215 switch (convs->kind)
4219 struct z_candidate *cand = convs->cand;
4220 tree convfn = cand->fn;
4223 if (DECL_CONSTRUCTOR_P (convfn))
4225 tree t = build_int_cst (build_pointer_type (DECL_CONTEXT (convfn)),
4228 args = build_tree_list (NULL_TREE, expr);
4229 /* We should never try to call the abstract or base constructor
4231 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (convfn)
4232 && !DECL_HAS_VTT_PARM_P (convfn));
4233 args = tree_cons (NULL_TREE, t, args);
4236 args = build_this (expr);
4237 expr = build_over_call (cand, LOOKUP_NORMAL);
4239 /* If this is a constructor or a function returning an aggr type,
4240 we need to build up a TARGET_EXPR. */
4241 if (DECL_CONSTRUCTOR_P (convfn))
4242 expr = build_cplus_new (totype, expr);
4244 /* The result of the call is then used to direct-initialize the object
4245 that is the destination of the copy-initialization. [dcl.init]
4247 Note that this step is not reflected in the conversion sequence;
4248 it affects the semantics when we actually perform the
4249 conversion, but is not considered during overload resolution.
4251 If the target is a class, that means call a ctor. */
4252 if (IS_AGGR_TYPE (totype)
4253 && (inner >= 0 || !lvalue_p (expr)))
4257 /* Core issue 84, now a DR, says that we don't
4258 allow UDCs for these args (which deliberately
4259 breaks copy-init of an auto_ptr<Base> from an
4260 auto_ptr<Derived>). */
4261 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION,
4268 (" initializing argument %P of %qD from result of %qD",
4269 argnum, fn, convfn);
4272 (" initializing temporary from result of %qD", convfn);
4274 expr = build_cplus_new (totype, expr);
4279 if (type_unknown_p (expr))
4280 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4281 /* Convert a constant to its underlying value, unless we are
4282 about to bind it to a reference, in which case we need to
4283 leave it as an lvalue. */
4285 expr = integral_constant_value (expr);
4286 if (convs->check_copy_constructor_p)
4287 check_constructor_callable (totype, expr);
4290 /* Call build_user_type_conversion again for the error. */
4291 return build_user_type_conversion
4292 (totype, convs->u.expr, LOOKUP_NORMAL);
4298 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4299 convs->kind == ck_ref_bind ? -1 : 1,
4300 /*issue_conversion_warnings=*/false,
4302 if (expr == error_mark_node)
4303 return error_mark_node;
4305 switch (convs->kind)
4308 if (! IS_AGGR_TYPE (totype))
4310 /* Else fall through. */
4312 if (convs->kind == ck_base && !convs->need_temporary_p)
4314 /* We are going to bind a reference directly to a base-class
4315 subobject of EXPR. */
4316 if (convs->check_copy_constructor_p)
4317 check_constructor_callable (TREE_TYPE (expr), expr);
4318 /* Build an expression for `*((base*) &expr)'. */
4319 expr = build_unary_op (ADDR_EXPR, expr, 0);
4320 expr = convert_to_base (expr, build_pointer_type (totype),
4321 !c_cast_p, /*nonnull=*/true);
4322 expr = build_indirect_ref (expr, "implicit conversion");
4326 /* Copy-initialization where the cv-unqualified version of the source
4327 type is the same class as, or a derived class of, the class of the
4328 destination [is treated as direct-initialization]. [dcl.init] */
4329 expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
4331 if (diagnostic_fn && fn)
4332 diagnostic_fn (" initializing argument %P of %qD", argnum, fn);
4333 return build_cplus_new (totype, expr);
4337 tree ref_type = totype;
4339 /* If necessary, create a temporary. */
4340 if (convs->need_temporary_p || !lvalue_p (expr))
4342 tree type = convs->u.next->type;
4343 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4345 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
4347 /* If the reference is volatile or non-const, we
4348 cannot create a temporary. */
4349 if (lvalue & clk_bitfield)
4350 error ("cannot bind bitfield %qE to %qT",
4352 else if (lvalue & clk_packed)
4353 error ("cannot bind packed field %qE to %qT",
4356 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4357 return error_mark_node;
4359 /* If the source is a packed field, and we must use a copy
4360 constructor, then building the target expr will require
4361 binding the field to the reference parameter to the
4362 copy constructor, and we'll end up with an infinite
4363 loop. If we can use a bitwise copy, then we'll be
4365 if ((lvalue & clk_packed)
4366 && CLASS_TYPE_P (type)
4367 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4369 error ("cannot bind packed field %qE to %qT",
4371 return error_mark_node;
4373 expr = build_target_expr_with_type (expr, type);
4376 /* Take the address of the thing to which we will bind the
4378 expr = build_unary_op (ADDR_EXPR, expr, 1);
4379 if (expr == error_mark_node)
4380 return error_mark_node;
4382 /* Convert it to a pointer to the type referred to by the
4383 reference. This will adjust the pointer if a derived to
4384 base conversion is being performed. */
4385 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4387 /* Convert the pointer to the desired reference type. */
4388 return build_nop (ref_type, expr);
4392 return decay_conversion (expr);
4395 /* Warn about deprecated conversion if appropriate. */
4396 string_conv_p (totype, expr, 1);
4401 expr = convert_to_base (expr, totype, !c_cast_p,
4403 return build_nop (totype, expr);
4406 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4412 return ocp_convert (totype, expr, CONV_IMPLICIT,
4413 LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
4416 /* Build a call to __builtin_trap. */
4419 call_builtin_trap (void)
4421 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4423 gcc_assert (fn != NULL);
4424 fn = build_call (fn, NULL_TREE);
4428 /* ARG is being passed to a varargs function. Perform any conversions
4429 required. Return the converted value. */
4432 convert_arg_to_ellipsis (tree arg)
4436 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4437 standard conversions are performed. */
4438 arg = decay_conversion (arg);
4441 If the argument has integral or enumeration type that is subject
4442 to the integral promotions (_conv.prom_), or a floating point
4443 type that is subject to the floating point promotion
4444 (_conv.fpprom_), the value of the argument is converted to the
4445 promoted type before the call. */
4446 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4447 && (TYPE_PRECISION (TREE_TYPE (arg))
4448 < TYPE_PRECISION (double_type_node)))
4449 arg = convert_to_real (double_type_node, arg);
4450 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4451 arg = perform_integral_promotions (arg);
4453 arg = require_complete_type (arg);
4455 if (arg != error_mark_node
4456 && !pod_type_p (TREE_TYPE (arg)))
4458 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4459 here and do a bitwise copy, but now cp_expr_size will abort if we
4461 If the call appears in the context of a sizeof expression,
4462 there is no need to emit a warning, since the expression won't be
4463 evaluated. We keep the builtin_trap just as a safety check. */
4464 if (!skip_evaluation)
4465 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4466 "call will abort at runtime", TREE_TYPE (arg));
4467 arg = call_builtin_trap ();
4468 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4475 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4478 build_x_va_arg (tree expr, tree type)
4480 if (processing_template_decl)
4481 return build_min (VA_ARG_EXPR, type, expr);
4483 type = complete_type_or_else (type, NULL_TREE);
4485 if (expr == error_mark_node || !type)
4486 return error_mark_node;
4488 if (! pod_type_p (type))
4490 /* Undefined behavior [expr.call] 5.2.2/7. */
4491 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4492 "call will abort at runtime", type);
4493 expr = convert (build_pointer_type (type), null_node);
4494 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4495 call_builtin_trap (), expr);
4496 expr = build_indirect_ref (expr, NULL);
4500 return build_va_arg (expr, type);
4503 /* TYPE has been given to va_arg. Apply the default conversions which
4504 would have happened when passed via ellipsis. Return the promoted
4505 type, or the passed type if there is no change. */
4508 cxx_type_promotes_to (tree type)
4512 /* Perform the array-to-pointer and function-to-pointer
4514 type = type_decays_to (type);
4516 promote = type_promotes_to (type);
4517 if (same_type_p (type, promote))
4523 /* ARG is a default argument expression being passed to a parameter of
4524 the indicated TYPE, which is a parameter to FN. Do any required
4525 conversions. Return the converted value. */
4528 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4530 /* If the ARG is an unparsed default argument expression, the
4531 conversion cannot be performed. */
4532 if (TREE_CODE (arg) == DEFAULT_ARG)
4534 error ("the default argument for parameter %d of %qD has "
4535 "not yet been parsed",
4537 return error_mark_node;
4540 if (fn && DECL_TEMPLATE_INFO (fn))
4541 arg = tsubst_default_argument (fn, type, arg);
4543 arg = break_out_target_exprs (arg);
4545 if (TREE_CODE (arg) == CONSTRUCTOR)
4547 arg = digest_init (type, arg);
4548 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4549 "default argument", fn, parmnum);
4553 /* This could get clobbered by the following call. */
4554 if (TREE_HAS_CONSTRUCTOR (arg))
4555 arg = copy_node (arg);
4557 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4558 "default argument", fn, parmnum);
4559 arg = convert_for_arg_passing (type, arg);
4565 /* Returns the type which will really be used for passing an argument of
4569 type_passed_as (tree type)
4571 /* Pass classes with copy ctors by invisible reference. */
4572 if (TREE_ADDRESSABLE (type))
4574 type = build_reference_type (type);
4575 /* There are no other pointers to this temporary. */
4576 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4578 else if (targetm.calls.promote_prototypes (type)
4579 && INTEGRAL_TYPE_P (type)
4580 && COMPLETE_TYPE_P (type)
4581 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4582 TYPE_SIZE (integer_type_node)))
4583 type = integer_type_node;
4588 /* Actually perform the appropriate conversion. */
4591 convert_for_arg_passing (tree type, tree val)
4593 if (val == error_mark_node)
4595 /* Pass classes with copy ctors by invisible reference. */
4596 else if (TREE_ADDRESSABLE (type))
4597 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4598 else if (targetm.calls.promote_prototypes (type)
4599 && INTEGRAL_TYPE_P (type)
4600 && COMPLETE_TYPE_P (type)
4601 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4602 TYPE_SIZE (integer_type_node)))
4603 val = perform_integral_promotions (val);
4604 if (warn_missing_format_attribute)
4606 tree rhstype = TREE_TYPE (val);
4607 const enum tree_code coder = TREE_CODE (rhstype);
4608 const enum tree_code codel = TREE_CODE (type);
4609 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4611 && check_missing_format_attribute (type, rhstype))
4612 warning (OPT_Wmissing_format_attribute,
4613 "argument of function call might be a candidate for a format attribute");
4618 /* Returns true iff FN is a function with magic varargs, i.e. ones for
4619 which no conversions at all should be done. This is true for some
4620 builtins which don't act like normal functions. */
4623 magic_varargs_p (tree fn)
4625 if (DECL_BUILT_IN (fn))
4626 switch (DECL_FUNCTION_CODE (fn))
4628 case BUILT_IN_CLASSIFY_TYPE:
4629 case BUILT_IN_CONSTANT_P:
4630 case BUILT_IN_NEXT_ARG:
4631 case BUILT_IN_STDARG_START:
4632 case BUILT_IN_VA_START:
4641 /* Subroutine of the various build_*_call functions. Overload resolution
4642 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4643 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4644 bitmask of various LOOKUP_* flags which apply to the call itself. */
4647 build_over_call (struct z_candidate *cand, int flags)
4650 tree args = cand->args;
4651 conversion **convs = cand->convs;
4653 tree converted_args = NULL_TREE;
4654 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4659 /* In a template, there is no need to perform all of the work that
4660 is normally done. We are only interested in the type of the call
4661 expression, i.e., the return type of the function. Any semantic
4662 errors will be deferred until the template is instantiated. */
4663 if (processing_template_decl)
4667 return_type = TREE_TYPE (TREE_TYPE (fn));
4668 expr = build3 (CALL_EXPR, return_type, fn, args, NULL_TREE);
4669 if (TREE_THIS_VOLATILE (fn) && cfun)
4670 current_function_returns_abnormally = 1;
4671 if (!VOID_TYPE_P (return_type))
4672 require_complete_type (return_type);
4673 return convert_from_reference (expr);
4676 /* Give any warnings we noticed during overload resolution. */
4679 struct candidate_warning *w;
4680 for (w = cand->warnings; w; w = w->next)
4681 joust (cand, w->loser, 1);
4684 if (DECL_FUNCTION_MEMBER_P (fn))
4686 /* If FN is a template function, two cases must be considered.
4691 template <class T> void f();
4693 template <class T> struct B {
4697 struct C : A, B<int> {
4699 using B<int>::g; // #2
4702 In case #1 where `A::f' is a member template, DECL_ACCESS is
4703 recorded in the primary template but not in its specialization.
4704 We check access of FN using its primary template.
4706 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
4707 because it is a member of class template B, DECL_ACCESS is
4708 recorded in the specialization `B<int>::g'. We cannot use its
4709 primary template because `B<T>::g' and `B<int>::g' may have
4710 different access. */
4711 if (DECL_TEMPLATE_INFO (fn)
4712 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
4713 perform_or_defer_access_check (cand->access_path,
4714 DECL_TI_TEMPLATE (fn));
4716 perform_or_defer_access_check (cand->access_path, fn);
4719 if (args && TREE_CODE (args) != TREE_LIST)
4720 args = build_tree_list (NULL_TREE, args);
4723 /* The implicit parameters to a constructor are not considered by overload
4724 resolution, and must be of the proper type. */
4725 if (DECL_CONSTRUCTOR_P (fn))
4727 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4728 arg = TREE_CHAIN (arg);
4729 parm = TREE_CHAIN (parm);
4730 /* We should never try to call the abstract constructor. */
4731 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
4733 if (DECL_HAS_VTT_PARM_P (fn))
4735 converted_args = tree_cons
4736 (NULL_TREE, TREE_VALUE (arg), converted_args);
4737 arg = TREE_CHAIN (arg);
4738 parm = TREE_CHAIN (parm);
4741 /* Bypass access control for 'this' parameter. */
4742 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4744 tree parmtype = TREE_VALUE (parm);
4745 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4749 if (convs[i]->bad_p)
4750 pedwarn ("passing %qT as %<this%> argument of %q#D discards qualifiers",
4751 TREE_TYPE (argtype), fn);
4753 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4754 X is called for an object that is not of type X, or of a type
4755 derived from X, the behavior is undefined.
4757 So we can assume that anything passed as 'this' is non-null, and
4758 optimize accordingly. */
4759 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
4760 /* Convert to the base in which the function was declared. */
4761 gcc_assert (cand->conversion_path != NULL_TREE);
4762 converted_arg = build_base_path (PLUS_EXPR,
4764 cand->conversion_path,
4766 /* Check that the base class is accessible. */
4767 if (!accessible_base_p (TREE_TYPE (argtype),
4768 BINFO_TYPE (cand->conversion_path), true))
4769 error ("%qT is not an accessible base of %qT",
4770 BINFO_TYPE (cand->conversion_path),
4771 TREE_TYPE (argtype));
4772 /* If fn was found by a using declaration, the conversion path
4773 will be to the derived class, not the base declaring fn. We
4774 must convert from derived to base. */
4775 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4776 TREE_TYPE (parmtype), ba_unique, NULL);
4777 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4780 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4781 parm = TREE_CHAIN (parm);
4782 arg = TREE_CHAIN (arg);
4788 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4790 tree type = TREE_VALUE (parm);
4793 val = convert_like_with_context
4794 (conv, TREE_VALUE (arg), fn, i - is_method);
4796 val = convert_for_arg_passing (type, val);
4797 converted_args = tree_cons (NULL_TREE, val, converted_args);
4800 /* Default arguments */
4801 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4803 = tree_cons (NULL_TREE,
4804 convert_default_arg (TREE_VALUE (parm),
4805 TREE_PURPOSE (parm),
4810 for (; arg; arg = TREE_CHAIN (arg))
4812 tree a = TREE_VALUE (arg);
4813 if (magic_varargs_p (fn))
4814 /* Do no conversions for magic varargs. */;
4816 a = convert_arg_to_ellipsis (a);
4817 converted_args = tree_cons (NULL_TREE, a, converted_args);
4820 converted_args = nreverse (converted_args);
4822 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4823 converted_args, TYPE_ARG_TYPES (TREE_TYPE (fn)));
4825 /* Avoid actually calling copy constructors and copy assignment operators,
4828 if (! flag_elide_constructors)
4829 /* Do things the hard way. */;
4830 else if (cand->num_convs == 1 && DECL_COPY_CONSTRUCTOR_P (fn))
4833 arg = skip_artificial_parms_for (fn, converted_args);
4834 arg = TREE_VALUE (arg);
4836 /* Pull out the real argument, disregarding const-correctness. */
4838 while (TREE_CODE (targ) == NOP_EXPR
4839 || TREE_CODE (targ) == NON_LVALUE_EXPR
4840 || TREE_CODE (targ) == CONVERT_EXPR)
4841 targ = TREE_OPERAND (targ, 0);
4842 if (TREE_CODE (targ) == ADDR_EXPR)
4844 targ = TREE_OPERAND (targ, 0);
4845 if (!same_type_ignoring_top_level_qualifiers_p
4846 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4855 arg = build_indirect_ref (arg, 0);
4857 /* [class.copy]: the copy constructor is implicitly defined even if
4858 the implementation elided its use. */
4859 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4862 /* If we're creating a temp and we already have one, don't create a
4863 new one. If we're not creating a temp but we get one, use
4864 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4865 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4866 temp or an INIT_EXPR otherwise. */
4867 if (integer_zerop (TREE_VALUE (args)))
4869 if (TREE_CODE (arg) == TARGET_EXPR)
4871 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4872 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4874 else if (TREE_CODE (arg) == TARGET_EXPR
4875 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4877 tree to = stabilize_reference
4878 (build_indirect_ref (TREE_VALUE (args), 0));
4880 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4884 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4886 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4888 tree to = stabilize_reference
4889 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4890 tree type = TREE_TYPE (to);
4891 tree as_base = CLASSTYPE_AS_BASE (type);
4893 arg = TREE_VALUE (TREE_CHAIN (converted_args));
4894 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
4896 arg = build_indirect_ref (arg, 0);
4897 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4901 /* We must only copy the non-tail padding parts.
4902 Use __builtin_memcpy for the bitwise copy. */
4906 args = tree_cons (NULL, TYPE_SIZE_UNIT (as_base), NULL);
4907 args = tree_cons (NULL, arg, args);
4908 t = build_unary_op (ADDR_EXPR, to, 0);
4909 args = tree_cons (NULL, t, args);
4910 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
4911 t = build_call (t, args);
4913 t = convert (TREE_TYPE (TREE_VALUE (args)), t);
4914 val = build_indirect_ref (t, 0);
4922 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4924 tree t, *p = &TREE_VALUE (converted_args);
4925 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4928 gcc_assert (binfo && binfo != error_mark_node);
4930 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4931 if (TREE_SIDE_EFFECTS (*p))
4932 *p = save_expr (*p);
4933 t = build_pointer_type (TREE_TYPE (fn));
4934 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4935 fn = build_java_interface_fn_ref (fn, *p);
4937 fn = build_vfn_ref (*p, DECL_VINDEX (fn));
4940 else if (DECL_INLINE (fn))
4941 fn = inline_conversion (fn);
4943 fn = build_addr_func (fn);
4945 return build_cxx_call (fn, converted_args);
4948 /* Build and return a call to FN, using ARGS. This function performs
4949 no overload resolution, conversion, or other high-level
4953 build_cxx_call (tree fn, tree args)
4957 fn = build_call (fn, args);
4959 /* If this call might throw an exception, note that fact. */
4960 fndecl = get_callee_fndecl (fn);
4961 if ((!fndecl || !TREE_NOTHROW (fndecl))
4962 && at_function_scope_p ()
4964 cp_function_chain->can_throw = 1;
4966 /* Some built-in function calls will be evaluated at compile-time in
4968 fn = fold_if_not_in_template (fn);
4970 if (VOID_TYPE_P (TREE_TYPE (fn)))
4973 fn = require_complete_type (fn);
4974 if (fn == error_mark_node)
4975 return error_mark_node;
4977 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4978 fn = build_cplus_new (TREE_TYPE (fn), fn);
4979 return convert_from_reference (fn);
4982 static GTY(()) tree java_iface_lookup_fn;
4984 /* Make an expression which yields the address of the Java interface
4985 method FN. This is achieved by generating a call to libjava's
4986 _Jv_LookupInterfaceMethodIdx(). */
4989 build_java_interface_fn_ref (tree fn, tree instance)
4991 tree lookup_args, lookup_fn, method, idx;
4992 tree klass_ref, iface, iface_ref;
4995 if (!java_iface_lookup_fn)
4997 tree endlink = build_void_list_node ();
4998 tree t = tree_cons (NULL_TREE, ptr_type_node,
4999 tree_cons (NULL_TREE, ptr_type_node,
5000 tree_cons (NULL_TREE, java_int_type_node,
5002 java_iface_lookup_fn
5003 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
5004 build_function_type (ptr_type_node, t),
5005 0, NOT_BUILT_IN, NULL, NULL_TREE);
5008 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5009 This is the first entry in the vtable. */
5010 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
5013 /* Get the java.lang.Class pointer for the interface being called. */
5014 iface = DECL_CONTEXT (fn);
5015 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5016 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5017 || DECL_CONTEXT (iface_ref) != iface)
5019 error ("could not find class$ field in java interface type %qT",
5021 return error_mark_node;
5023 iface_ref = build_address (iface_ref);
5024 iface_ref = convert (build_pointer_type (iface), iface_ref);
5026 /* Determine the itable index of FN. */
5028 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5030 if (!DECL_VIRTUAL_P (method))
5036 idx = build_int_cst (NULL_TREE, i);
5038 lookup_args = tree_cons (NULL_TREE, klass_ref,
5039 tree_cons (NULL_TREE, iface_ref,
5040 build_tree_list (NULL_TREE, idx)));
5041 lookup_fn = build1 (ADDR_EXPR,
5042 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5043 java_iface_lookup_fn);
5044 return build3 (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
5047 /* Returns the value to use for the in-charge parameter when making a
5048 call to a function with the indicated NAME.
5050 FIXME:Can't we find a neater way to do this mapping? */
5053 in_charge_arg_for_name (tree name)
5055 if (name == base_ctor_identifier
5056 || name == base_dtor_identifier)
5057 return integer_zero_node;
5058 else if (name == complete_ctor_identifier)
5059 return integer_one_node;
5060 else if (name == complete_dtor_identifier)
5061 return integer_two_node;
5062 else if (name == deleting_dtor_identifier)
5063 return integer_three_node;
5065 /* This function should only be called with one of the names listed
5071 /* Build a call to a constructor, destructor, or an assignment
5072 operator for INSTANCE, an expression with class type. NAME
5073 indicates the special member function to call; ARGS are the
5074 arguments. BINFO indicates the base of INSTANCE that is to be
5075 passed as the `this' parameter to the member function called.
5077 FLAGS are the LOOKUP_* flags to use when processing the call.
5079 If NAME indicates a complete object constructor, INSTANCE may be
5080 NULL_TREE. In this case, the caller will call build_cplus_new to
5081 store the newly constructed object into a VAR_DECL. */
5084 build_special_member_call (tree instance, tree name, tree args,
5085 tree binfo, int flags)
5088 /* The type of the subobject to be constructed or destroyed. */
5091 gcc_assert (name == complete_ctor_identifier
5092 || name == base_ctor_identifier
5093 || name == complete_dtor_identifier
5094 || name == base_dtor_identifier
5095 || name == deleting_dtor_identifier
5096 || name == ansi_assopname (NOP_EXPR));
5099 /* Resolve the name. */
5100 if (!complete_type_or_else (binfo, NULL_TREE))
5101 return error_mark_node;
5103 binfo = TYPE_BINFO (binfo);
5106 gcc_assert (binfo != NULL_TREE);
5108 class_type = BINFO_TYPE (binfo);
5110 /* Handle the special case where INSTANCE is NULL_TREE. */
5111 if (name == complete_ctor_identifier && !instance)
5113 instance = build_int_cst (build_pointer_type (class_type), 0);
5114 instance = build1 (INDIRECT_REF, class_type, instance);
5118 if (name == complete_dtor_identifier
5119 || name == base_dtor_identifier
5120 || name == deleting_dtor_identifier)
5121 gcc_assert (args == NULL_TREE);
5123 /* Convert to the base class, if necessary. */
5124 if (!same_type_ignoring_top_level_qualifiers_p
5125 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5127 if (name != ansi_assopname (NOP_EXPR))
5128 /* For constructors and destructors, either the base is
5129 non-virtual, or it is virtual but we are doing the
5130 conversion from a constructor or destructor for the
5131 complete object. In either case, we can convert
5133 instance = convert_to_base_statically (instance, binfo);
5135 /* However, for assignment operators, we must convert
5136 dynamically if the base is virtual. */
5137 instance = build_base_path (PLUS_EXPR, instance,
5138 binfo, /*nonnull=*/1);
5142 gcc_assert (instance != NULL_TREE);
5144 fns = lookup_fnfields (binfo, name, 1);
5146 /* When making a call to a constructor or destructor for a subobject
5147 that uses virtual base classes, pass down a pointer to a VTT for
5149 if ((name == base_ctor_identifier
5150 || name == base_dtor_identifier)
5151 && CLASSTYPE_VBASECLASSES (class_type))
5156 /* If the current function is a complete object constructor
5157 or destructor, then we fetch the VTT directly.
5158 Otherwise, we look it up using the VTT we were given. */
5159 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5160 vtt = decay_conversion (vtt);
5161 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5162 build2 (EQ_EXPR, boolean_type_node,
5163 current_in_charge_parm, integer_zero_node),
5166 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5167 sub_vtt = build2 (PLUS_EXPR, TREE_TYPE (vtt), vtt,
5168 BINFO_SUBVTT_INDEX (binfo));
5170 args = tree_cons (NULL_TREE, sub_vtt, args);
5173 return build_new_method_call (instance, fns, args,
5174 TYPE_BINFO (BINFO_TYPE (binfo)),
5178 /* Return the NAME, as a C string. The NAME indicates a function that
5179 is a member of TYPE. *FREE_P is set to true if the caller must
5180 free the memory returned.
5182 Rather than go through all of this, we should simply set the names
5183 of constructors and destructors appropriately, and dispense with
5184 ctor_identifier, dtor_identifier, etc. */
5187 name_as_c_string (tree name, tree type, bool *free_p)
5191 /* Assume that we will not allocate memory. */
5193 /* Constructors and destructors are special. */
5194 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5197 = (char *) IDENTIFIER_POINTER (constructor_name (type));
5198 /* For a destructor, add the '~'. */
5199 if (name == complete_dtor_identifier
5200 || name == base_dtor_identifier
5201 || name == deleting_dtor_identifier)
5203 pretty_name = concat ("~", pretty_name, NULL);
5204 /* Remember that we need to free the memory allocated. */
5208 else if (IDENTIFIER_TYPENAME_P (name))
5210 pretty_name = concat ("operator ",
5211 type_as_string (TREE_TYPE (name),
5212 TFF_PLAIN_IDENTIFIER),
5214 /* Remember that we need to free the memory allocated. */
5218 pretty_name = (char *) IDENTIFIER_POINTER (name);
5223 /* Build a call to "INSTANCE.FN (ARGS)". */
5226 build_new_method_call (tree instance, tree fns, tree args,
5227 tree conversion_path, int flags)
5229 struct z_candidate *candidates = 0, *cand;
5230 tree explicit_targs = NULL_TREE;
5231 tree basetype = NULL_TREE;
5234 tree mem_args = NULL_TREE, instance_ptr;
5240 int template_only = 0;
5247 gcc_assert (instance != NULL_TREE);
5249 if (error_operand_p (instance)
5250 || error_operand_p (fns)
5251 || args == error_mark_node)
5252 return error_mark_node;
5254 orig_instance = instance;
5258 if (processing_template_decl)
5260 instance = build_non_dependent_expr (instance);
5261 if (!BASELINK_P (fns)
5262 && TREE_CODE (fns) != PSEUDO_DTOR_EXPR
5263 && TREE_TYPE (fns) != unknown_type_node)
5264 fns = build_non_dependent_expr (fns);
5265 args = build_non_dependent_args (orig_args);
5268 /* Process the argument list. */
5270 args = resolve_args (args);
5271 if (args == error_mark_node)
5272 return error_mark_node;
5274 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5275 instance_ptr = build_this (instance);
5277 if (!BASELINK_P (fns))
5279 error ("call to non-function %qD", fns);
5280 return error_mark_node;
5283 if (!conversion_path)
5284 conversion_path = BASELINK_BINFO (fns);
5285 access_binfo = BASELINK_ACCESS_BINFO (fns);
5286 optype = BASELINK_OPTYPE (fns);
5287 fns = BASELINK_FUNCTIONS (fns);
5289 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5291 explicit_targs = TREE_OPERAND (fns, 1);
5292 fns = TREE_OPERAND (fns, 0);
5296 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5297 || TREE_CODE (fns) == TEMPLATE_DECL
5298 || TREE_CODE (fns) == OVERLOAD);
5300 /* XXX this should be handled before we get here. */
5301 if (! IS_AGGR_TYPE (basetype))
5303 if ((flags & LOOKUP_COMPLAIN) && basetype != error_mark_node)
5304 error ("request for member %qD in %qE, which is of non-aggregate "
5306 fns, instance, basetype);
5308 return error_mark_node;
5311 fn = get_first_fn (fns);
5312 name = DECL_NAME (fn);
5314 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5316 /* Callers should explicitly indicate whether they want to construct
5317 the complete object or just the part without virtual bases. */
5318 gcc_assert (name != ctor_identifier);
5319 /* Similarly for destructors. */
5320 gcc_assert (name != dtor_identifier);
5323 /* It's OK to call destructors on cv-qualified objects. Therefore,
5324 convert the INSTANCE_PTR to the unqualified type, if necessary. */
5325 if (DECL_DESTRUCTOR_P (fn))
5327 tree type = build_pointer_type (basetype);
5328 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5329 instance_ptr = build_nop (type, instance_ptr);
5332 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5333 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5335 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5336 p = conversion_obstack_alloc (0);
5338 for (fn = fns; fn; fn = OVL_NEXT (fn))
5340 tree t = OVL_CURRENT (fn);
5343 /* We can end up here for copy-init of same or base class. */
5344 if ((flags & LOOKUP_ONLYCONVERTING)
5345 && DECL_NONCONVERTING_P (t))
5348 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5349 this_arglist = mem_args;
5351 this_arglist = args;
5353 if (TREE_CODE (t) == TEMPLATE_DECL)
5354 /* A member template. */
5355 add_template_candidate (&candidates, t,
5358 this_arglist, optype,
5363 else if (! template_only)
5364 add_function_candidate (&candidates, t,
5372 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5375 if (!COMPLETE_TYPE_P (basetype))
5376 cxx_incomplete_type_error (instance_ptr, basetype);
5382 pretty_name = name_as_c_string (name, basetype, &free_p);
5383 error ("no matching function for call to %<%T::%s(%A)%#V%>",
5384 basetype, pretty_name, user_args,
5385 TREE_TYPE (TREE_TYPE (instance_ptr)));
5389 print_z_candidates (candidates);
5390 call = error_mark_node;
5394 cand = tourney (candidates);
5400 pretty_name = name_as_c_string (name, basetype, &free_p);
5401 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
5403 print_z_candidates (candidates);
5406 call = error_mark_node;
5410 if (!(flags & LOOKUP_NONVIRTUAL)
5411 && DECL_PURE_VIRTUAL_P (cand->fn)
5412 && instance == current_class_ref
5413 && (DECL_CONSTRUCTOR_P (current_function_decl)
5414 || DECL_DESTRUCTOR_P (current_function_decl)))
5415 /* This is not an error, it is runtime undefined
5417 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
5418 "abstract virtual %q#D called from constructor"
5419 : "abstract virtual %q#D called from destructor"),
5422 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5423 && is_dummy_object (instance_ptr))
5425 error ("cannot call member function %qD without object",
5427 call = error_mark_node;
5431 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5432 && resolves_to_fixed_type_p (instance, 0))
5433 flags |= LOOKUP_NONVIRTUAL;
5435 call = build_over_call (cand, flags);
5437 /* In an expression of the form `a->f()' where `f' turns
5438 out to be a static member function, `a' is
5439 none-the-less evaluated. */
5440 if (TREE_CODE (TREE_TYPE (cand->fn)) != METHOD_TYPE
5441 && !is_dummy_object (instance_ptr)
5442 && TREE_SIDE_EFFECTS (instance))
5443 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5449 if (processing_template_decl && call != error_mark_node)
5450 call = (build_min_non_dep
5452 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5453 orig_args, NULL_TREE));
5455 /* Free all the conversions we allocated. */
5456 obstack_free (&conversion_obstack, p);
5461 /* Returns true iff standard conversion sequence ICS1 is a proper
5462 subsequence of ICS2. */
5465 is_subseq (conversion *ics1, conversion *ics2)
5467 /* We can assume that a conversion of the same code
5468 between the same types indicates a subsequence since we only get
5469 here if the types we are converting from are the same. */
5471 while (ics1->kind == ck_rvalue
5472 || ics1->kind == ck_lvalue)
5473 ics1 = ics1->u.next;
5477 while (ics2->kind == ck_rvalue
5478 || ics2->kind == ck_lvalue)
5479 ics2 = ics2->u.next;
5481 if (ics2->kind == ck_user
5482 || ics2->kind == ck_ambig
5483 || ics2->kind == ck_identity)
5484 /* At this point, ICS1 cannot be a proper subsequence of
5485 ICS2. We can get a USER_CONV when we are comparing the
5486 second standard conversion sequence of two user conversion
5490 ics2 = ics2->u.next;
5492 if (ics2->kind == ics1->kind
5493 && same_type_p (ics2->type, ics1->type)
5494 && same_type_p (ics2->u.next->type,
5495 ics1->u.next->type))
5500 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5501 be any _TYPE nodes. */
5504 is_properly_derived_from (tree derived, tree base)
5506 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5507 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5510 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5511 considers every class derived from itself. */
5512 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5513 && DERIVED_FROM_P (base, derived));
5516 /* We build the ICS for an implicit object parameter as a pointer
5517 conversion sequence. However, such a sequence should be compared
5518 as if it were a reference conversion sequence. If ICS is the
5519 implicit conversion sequence for an implicit object parameter,
5520 modify it accordingly. */
5523 maybe_handle_implicit_object (conversion **ics)
5527 /* [over.match.funcs]
5529 For non-static member functions, the type of the
5530 implicit object parameter is "reference to cv X"
5531 where X is the class of which the function is a
5532 member and cv is the cv-qualification on the member
5533 function declaration. */
5534 conversion *t = *ics;
5535 tree reference_type;
5537 /* The `this' parameter is a pointer to a class type. Make the
5538 implicit conversion talk about a reference to that same class
5540 reference_type = TREE_TYPE (t->type);
5541 reference_type = build_reference_type (reference_type);
5543 if (t->kind == ck_qual)
5545 if (t->kind == ck_ptr)
5547 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
5548 t = direct_reference_binding (reference_type, t);
5553 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5554 and return the type to which the reference refers. Otherwise,
5555 leave *ICS unchanged and return NULL_TREE. */
5558 maybe_handle_ref_bind (conversion **ics)
5560 if ((*ics)->kind == ck_ref_bind)
5562 conversion *old_ics = *ics;
5563 tree type = TREE_TYPE (old_ics->type);
5564 *ics = old_ics->u.next;
5565 (*ics)->user_conv_p = old_ics->user_conv_p;
5566 (*ics)->bad_p = old_ics->bad_p;
5573 /* Compare two implicit conversion sequences according to the rules set out in
5574 [over.ics.rank]. Return values:
5576 1: ics1 is better than ics2
5577 -1: ics2 is better than ics1
5578 0: ics1 and ics2 are indistinguishable */
5581 compare_ics (conversion *ics1, conversion *ics2)
5587 tree deref_from_type1 = NULL_TREE;
5588 tree deref_from_type2 = NULL_TREE;
5589 tree deref_to_type1 = NULL_TREE;
5590 tree deref_to_type2 = NULL_TREE;
5591 conversion_rank rank1, rank2;
5593 /* REF_BINDING is nonzero if the result of the conversion sequence
5594 is a reference type. In that case TARGET_TYPE is the
5595 type referred to by the reference. */
5599 /* Handle implicit object parameters. */
5600 maybe_handle_implicit_object (&ics1);
5601 maybe_handle_implicit_object (&ics2);
5603 /* Handle reference parameters. */
5604 target_type1 = maybe_handle_ref_bind (&ics1);
5605 target_type2 = maybe_handle_ref_bind (&ics2);
5609 When comparing the basic forms of implicit conversion sequences (as
5610 defined in _over.best.ics_)
5612 --a standard conversion sequence (_over.ics.scs_) is a better
5613 conversion sequence than a user-defined conversion sequence
5614 or an ellipsis conversion sequence, and
5616 --a user-defined conversion sequence (_over.ics.user_) is a
5617 better conversion sequence than an ellipsis conversion sequence
5618 (_over.ics.ellipsis_). */
5619 rank1 = CONVERSION_RANK (ics1);
5620 rank2 = CONVERSION_RANK (ics2);
5624 else if (rank1 < rank2)
5627 if (rank1 == cr_bad)
5629 /* XXX Isn't this an extension? */
5630 /* Both ICS are bad. We try to make a decision based on what
5631 would have happened if they'd been good. */
5632 if (ics1->user_conv_p > ics2->user_conv_p
5633 || ics1->rank > ics2->rank)
5635 else if (ics1->user_conv_p < ics2->user_conv_p
5636 || ics1->rank < ics2->rank)
5639 /* We couldn't make up our minds; try to figure it out below. */
5642 if (ics1->ellipsis_p)
5643 /* Both conversions are ellipsis conversions. */
5646 /* User-defined conversion sequence U1 is a better conversion sequence
5647 than another user-defined conversion sequence U2 if they contain the
5648 same user-defined conversion operator or constructor and if the sec-
5649 ond standard conversion sequence of U1 is better than the second
5650 standard conversion sequence of U2. */
5652 if (ics1->user_conv_p)
5657 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
5658 if (t1->kind == ck_ambig)
5660 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
5661 if (t2->kind == ck_ambig)
5664 if (t1->cand->fn != t2->cand->fn)
5667 /* We can just fall through here, after setting up
5668 FROM_TYPE1 and FROM_TYPE2. */
5669 from_type1 = t1->type;
5670 from_type2 = t2->type;
5677 /* We're dealing with two standard conversion sequences.
5681 Standard conversion sequence S1 is a better conversion
5682 sequence than standard conversion sequence S2 if
5684 --S1 is a proper subsequence of S2 (comparing the conversion
5685 sequences in the canonical form defined by _over.ics.scs_,
5686 excluding any Lvalue Transformation; the identity
5687 conversion sequence is considered to be a subsequence of
5688 any non-identity conversion sequence */
5691 while (t1->kind != ck_identity)
5693 from_type1 = t1->type;
5696 while (t2->kind != ck_identity)
5698 from_type2 = t2->type;
5701 if (same_type_p (from_type1, from_type2))
5703 if (is_subseq (ics1, ics2))
5705 if (is_subseq (ics2, ics1))
5708 /* Otherwise, one sequence cannot be a subsequence of the other; they
5709 don't start with the same type. This can happen when comparing the
5710 second standard conversion sequence in two user-defined conversion
5717 --the rank of S1 is better than the rank of S2 (by the rules
5720 Standard conversion sequences are ordered by their ranks: an Exact
5721 Match is a better conversion than a Promotion, which is a better
5722 conversion than a Conversion.
5724 Two conversion sequences with the same rank are indistinguishable
5725 unless one of the following rules applies:
5727 --A conversion that is not a conversion of a pointer, or pointer
5728 to member, to bool is better than another conversion that is such
5731 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5732 so that we do not have to check it explicitly. */
5733 if (ics1->rank < ics2->rank)
5735 else if (ics2->rank < ics1->rank)
5738 to_type1 = ics1->type;
5739 to_type2 = ics2->type;
5741 if (TYPE_PTR_P (from_type1)
5742 && TYPE_PTR_P (from_type2)
5743 && TYPE_PTR_P (to_type1)
5744 && TYPE_PTR_P (to_type2))
5746 deref_from_type1 = TREE_TYPE (from_type1);
5747 deref_from_type2 = TREE_TYPE (from_type2);
5748 deref_to_type1 = TREE_TYPE (to_type1);
5749 deref_to_type2 = TREE_TYPE (to_type2);
5751 /* The rules for pointers to members A::* are just like the rules
5752 for pointers A*, except opposite: if B is derived from A then
5753 A::* converts to B::*, not vice versa. For that reason, we
5754 switch the from_ and to_ variables here. */
5755 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5756 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5757 || (TYPE_PTRMEMFUNC_P (from_type1)
5758 && TYPE_PTRMEMFUNC_P (from_type2)
5759 && TYPE_PTRMEMFUNC_P (to_type1)
5760 && TYPE_PTRMEMFUNC_P (to_type2)))
5762 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5763 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5764 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5765 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5768 if (deref_from_type1 != NULL_TREE
5769 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5770 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5772 /* This was one of the pointer or pointer-like conversions.
5776 --If class B is derived directly or indirectly from class A,
5777 conversion of B* to A* is better than conversion of B* to
5778 void*, and conversion of A* to void* is better than
5779 conversion of B* to void*. */
5780 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5781 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5783 if (is_properly_derived_from (deref_from_type1,
5786 else if (is_properly_derived_from (deref_from_type2,
5790 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5791 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5793 if (same_type_p (deref_from_type1, deref_from_type2))
5795 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5797 if (is_properly_derived_from (deref_from_type1,
5801 /* We know that DEREF_TO_TYPE1 is `void' here. */
5802 else if (is_properly_derived_from (deref_from_type1,
5807 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5808 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5812 --If class B is derived directly or indirectly from class A
5813 and class C is derived directly or indirectly from B,
5815 --conversion of C* to B* is better than conversion of C* to
5818 --conversion of B* to A* is better than conversion of C* to
5820 if (same_type_p (deref_from_type1, deref_from_type2))
5822 if (is_properly_derived_from (deref_to_type1,
5825 else if (is_properly_derived_from (deref_to_type2,
5829 else if (same_type_p (deref_to_type1, deref_to_type2))
5831 if (is_properly_derived_from (deref_from_type2,
5834 else if (is_properly_derived_from (deref_from_type1,
5840 else if (CLASS_TYPE_P (non_reference (from_type1))
5841 && same_type_p (from_type1, from_type2))
5843 tree from = non_reference (from_type1);
5847 --binding of an expression of type C to a reference of type
5848 B& is better than binding an expression of type C to a
5849 reference of type A&
5851 --conversion of C to B is better than conversion of C to A, */
5852 if (is_properly_derived_from (from, to_type1)
5853 && is_properly_derived_from (from, to_type2))
5855 if (is_properly_derived_from (to_type1, to_type2))
5857 else if (is_properly_derived_from (to_type2, to_type1))
5861 else if (CLASS_TYPE_P (non_reference (to_type1))
5862 && same_type_p (to_type1, to_type2))
5864 tree to = non_reference (to_type1);
5868 --binding of an expression of type B to a reference of type
5869 A& is better than binding an expression of type C to a
5870 reference of type A&,
5872 --conversion of B to A is better than conversion of C to A */
5873 if (is_properly_derived_from (from_type1, to)
5874 && is_properly_derived_from (from_type2, to))
5876 if (is_properly_derived_from (from_type2, from_type1))
5878 else if (is_properly_derived_from (from_type1, from_type2))
5885 --S1 and S2 differ only in their qualification conversion and yield
5886 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5887 qualification signature of type T1 is a proper subset of the cv-
5888 qualification signature of type T2 */
5889 if (ics1->kind == ck_qual
5890 && ics2->kind == ck_qual
5891 && same_type_p (from_type1, from_type2))
5892 return comp_cv_qual_signature (to_type1, to_type2);
5896 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5897 types to which the references refer are the same type except for
5898 top-level cv-qualifiers, and the type to which the reference
5899 initialized by S2 refers is more cv-qualified than the type to
5900 which the reference initialized by S1 refers */
5902 if (target_type1 && target_type2
5903 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5904 return comp_cv_qualification (target_type2, target_type1);
5906 /* Neither conversion sequence is better than the other. */
5910 /* The source type for this standard conversion sequence. */
5913 source_type (conversion *t)
5915 for (;; t = t->u.next)
5917 if (t->kind == ck_user
5918 || t->kind == ck_ambig
5919 || t->kind == ck_identity)
5925 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5926 a pointer to LOSER and re-running joust to produce the warning if WINNER
5927 is actually used. */
5930 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5932 candidate_warning *cw;
5934 cw = conversion_obstack_alloc (sizeof (candidate_warning));
5936 cw->next = winner->warnings;
5937 winner->warnings = cw;
5940 /* Compare two candidates for overloading as described in
5941 [over.match.best]. Return values:
5943 1: cand1 is better than cand2
5944 -1: cand2 is better than cand1
5945 0: cand1 and cand2 are indistinguishable */
5948 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5951 int off1 = 0, off2 = 0;
5955 /* Candidates that involve bad conversions are always worse than those
5957 if (cand1->viable > cand2->viable)
5959 if (cand1->viable < cand2->viable)
5962 /* If we have two pseudo-candidates for conversions to the same type,
5963 or two candidates for the same function, arbitrarily pick one. */
5964 if (cand1->fn == cand2->fn
5965 && (IS_TYPE_OR_DECL_P (cand1->fn)))
5968 /* a viable function F1
5969 is defined to be a better function than another viable function F2 if
5970 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5971 ICSi(F2), and then */
5973 /* for some argument j, ICSj(F1) is a better conversion sequence than
5976 /* For comparing static and non-static member functions, we ignore
5977 the implicit object parameter of the non-static function. The
5978 standard says to pretend that the static function has an object
5979 parm, but that won't work with operator overloading. */
5980 len = cand1->num_convs;
5981 if (len != cand2->num_convs)
5983 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
5984 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
5986 gcc_assert (static_1 != static_2);
5997 for (i = 0; i < len; ++i)
5999 conversion *t1 = cand1->convs[i + off1];
6000 conversion *t2 = cand2->convs[i + off2];
6001 int comp = compare_ics (t1, t2);
6006 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6007 == cr_std + cr_promotion)
6008 && t1->kind == ck_std
6009 && t2->kind == ck_std
6010 && TREE_CODE (t1->type) == INTEGER_TYPE
6011 && TREE_CODE (t2->type) == INTEGER_TYPE
6012 && (TYPE_PRECISION (t1->type)
6013 == TYPE_PRECISION (t2->type))
6014 && (TYPE_UNSIGNED (t1->u.next->type)
6015 || (TREE_CODE (t1->u.next->type)
6018 tree type = t1->u.next->type;
6020 struct z_candidate *w, *l;
6022 type1 = t1->type, type2 = t2->type,
6023 w = cand1, l = cand2;
6025 type1 = t2->type, type2 = t1->type,
6026 w = cand2, l = cand1;
6030 warning (0, "passing %qT chooses %qT over %qT",
6031 type, type1, type2);
6032 warning (0, " in call to %qD", w->fn);
6038 if (winner && comp != winner)
6047 /* warn about confusing overload resolution for user-defined conversions,
6048 either between a constructor and a conversion op, or between two
6050 if (winner && warn_conversion && cand1->second_conv
6051 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6052 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6054 struct z_candidate *w, *l;
6055 bool give_warning = false;
6058 w = cand1, l = cand2;
6060 w = cand2, l = cand1;
6062 /* We don't want to complain about `X::operator T1 ()'
6063 beating `X::operator T2 () const', when T2 is a no less
6064 cv-qualified version of T1. */
6065 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6066 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6068 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6069 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6071 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6076 if (!comp_ptr_ttypes (t, f))
6077 give_warning = true;
6080 give_warning = true;
6086 tree source = source_type (w->convs[0]);
6087 if (! DECL_CONSTRUCTOR_P (w->fn))
6088 source = TREE_TYPE (source);
6089 warning (0, "choosing %qD over %qD", w->fn, l->fn);
6090 warning (0, " for conversion from %qT to %qT",
6091 source, w->second_conv->type);
6092 warning (0, " because conversion sequence for the argument is better");
6102 F1 is a non-template function and F2 is a template function
6105 if (!cand1->template_decl && cand2->template_decl)
6107 else if (cand1->template_decl && !cand2->template_decl)
6111 F1 and F2 are template functions and the function template for F1 is
6112 more specialized than the template for F2 according to the partial
6115 if (cand1->template_decl && cand2->template_decl)
6117 winner = more_specialized_fn
6118 (TI_TEMPLATE (cand1->template_decl),
6119 TI_TEMPLATE (cand2->template_decl),
6120 /* Tell the deduction code how many real function arguments
6121 we saw, not counting the implicit 'this' argument. But,
6122 add_function_candidate() suppresses the "this" argument
6125 [temp.func.order]: The presence of unused ellipsis and default
6126 arguments has no effect on the partial ordering of function
6129 - (DECL_NONSTATIC_MEMBER_FUNCTION_P (cand1->fn)
6130 - DECL_CONSTRUCTOR_P (cand1->fn)));
6136 the context is an initialization by user-defined conversion (see
6137 _dcl.init_ and _over.match.user_) and the standard conversion
6138 sequence from the return type of F1 to the destination type (i.e.,
6139 the type of the entity being initialized) is a better conversion
6140 sequence than the standard conversion sequence from the return type
6141 of F2 to the destination type. */
6143 if (cand1->second_conv)
6145 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6150 /* Check whether we can discard a builtin candidate, either because we
6151 have two identical ones or matching builtin and non-builtin candidates.
6153 (Pedantically in the latter case the builtin which matched the user
6154 function should not be added to the overload set, but we spot it here.
6157 ... the builtin candidates include ...
6158 - do not have the same parameter type list as any non-template
6159 non-member candidate. */
6161 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6162 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6164 for (i = 0; i < len; ++i)
6165 if (!same_type_p (cand1->convs[i]->type,
6166 cand2->convs[i]->type))
6168 if (i == cand1->num_convs)
6170 if (cand1->fn == cand2->fn)
6171 /* Two built-in candidates; arbitrarily pick one. */
6173 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6174 /* cand1 is built-in; prefer cand2. */
6177 /* cand2 is built-in; prefer cand1. */
6182 /* If the two functions are the same (this can happen with declarations
6183 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6184 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6185 && equal_functions (cand1->fn, cand2->fn))
6190 /* Extension: If the worst conversion for one candidate is worse than the
6191 worst conversion for the other, take the first. */
6194 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6195 struct z_candidate *w = 0, *l = 0;
6197 for (i = 0; i < len; ++i)
6199 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6200 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6201 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6202 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6205 winner = 1, w = cand1, l = cand2;
6207 winner = -1, w = cand2, l = cand1;
6213 ISO C++ says that these are ambiguous, even \
6214 though the worst conversion for the first is better than \
6215 the worst conversion for the second:");
6216 print_z_candidate (_("candidate 1:"), w);
6217 print_z_candidate (_("candidate 2:"), l);
6225 gcc_assert (!winner);
6229 /* Given a list of candidates for overloading, find the best one, if any.
6230 This algorithm has a worst case of O(2n) (winner is last), and a best
6231 case of O(n/2) (totally ambiguous); much better than a sorting
6234 static struct z_candidate *
6235 tourney (struct z_candidate *candidates)
6237 struct z_candidate *champ = candidates, *challenger;
6239 int champ_compared_to_predecessor = 0;
6241 /* Walk through the list once, comparing each current champ to the next
6242 candidate, knocking out a candidate or two with each comparison. */
6244 for (challenger = champ->next; challenger; )
6246 fate = joust (champ, challenger, 0);
6248 challenger = challenger->next;
6253 champ = challenger->next;
6256 champ_compared_to_predecessor = 0;
6261 champ_compared_to_predecessor = 1;
6264 challenger = champ->next;
6268 /* Make sure the champ is better than all the candidates it hasn't yet
6269 been compared to. */
6271 for (challenger = candidates;
6273 && !(champ_compared_to_predecessor && challenger->next == champ);
6274 challenger = challenger->next)
6276 fate = joust (champ, challenger, 0);
6284 /* Returns nonzero if things of type FROM can be converted to TO. */
6287 can_convert (tree to, tree from)
6289 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6292 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6295 can_convert_arg (tree to, tree from, tree arg, int flags)
6301 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6302 p = conversion_obstack_alloc (0);
6304 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6306 ok_p = (t && !t->bad_p);
6308 /* Free all the conversions we allocated. */
6309 obstack_free (&conversion_obstack, p);
6314 /* Like can_convert_arg, but allows dubious conversions as well. */
6317 can_convert_arg_bad (tree to, tree from, tree arg)
6322 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6323 p = conversion_obstack_alloc (0);
6324 /* Try to perform the conversion. */
6325 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6327 /* Free all the conversions we allocated. */
6328 obstack_free (&conversion_obstack, p);
6333 /* Convert EXPR to TYPE. Return the converted expression.
6335 Note that we allow bad conversions here because by the time we get to
6336 this point we are committed to doing the conversion. If we end up
6337 doing a bad conversion, convert_like will complain. */
6340 perform_implicit_conversion (tree type, tree expr)
6345 if (error_operand_p (expr))
6346 return error_mark_node;
6348 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6349 p = conversion_obstack_alloc (0);
6351 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6356 error ("could not convert %qE to %qT", expr, type);
6357 expr = error_mark_node;
6360 expr = convert_like (conv, expr);
6362 /* Free all the conversions we allocated. */
6363 obstack_free (&conversion_obstack, p);
6368 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6369 permitted. If the conversion is valid, the converted expression is
6370 returned. Otherwise, NULL_TREE is returned, except in the case
6371 that TYPE is a class type; in that case, an error is issued. If
6372 C_CAST_P is true, then this direction initialization is taking
6373 place as part of a static_cast being attempted as part of a C-style
6377 perform_direct_initialization_if_possible (tree type,
6384 if (type == error_mark_node || error_operand_p (expr))
6385 return error_mark_node;
6388 If the destination type is a (possibly cv-qualified) class type:
6390 -- If the initialization is direct-initialization ...,
6391 constructors are considered. ... If no constructor applies, or
6392 the overload resolution is ambiguous, the initialization is
6394 if (CLASS_TYPE_P (type))
6396 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6397 build_tree_list (NULL_TREE, expr),
6398 type, LOOKUP_NORMAL);
6399 return build_cplus_new (type, expr);
6402 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6403 p = conversion_obstack_alloc (0);
6405 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6408 if (!conv || conv->bad_p)
6411 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6412 /*issue_conversion_warnings=*/false,
6415 /* Free all the conversions we allocated. */
6416 obstack_free (&conversion_obstack, p);
6421 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6422 is being bound to a temporary. Create and return a new VAR_DECL
6423 with the indicated TYPE; this variable will store the value to
6424 which the reference is bound. */
6427 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6431 /* Create the variable. */
6432 var = build_decl (VAR_DECL, NULL_TREE, type);
6433 DECL_ARTIFICIAL (var) = 1;
6434 DECL_IGNORED_P (var) = 1;
6435 TREE_USED (var) = 1;
6437 /* Register the variable. */
6438 if (TREE_STATIC (decl))
6440 /* Namespace-scope or local static; give it a mangled name. */
6443 TREE_STATIC (var) = 1;
6444 name = mangle_ref_init_variable (decl);
6445 DECL_NAME (var) = name;
6446 SET_DECL_ASSEMBLER_NAME (var, name);
6447 var = pushdecl_top_level (var);
6451 /* Create a new cleanup level if necessary. */
6452 maybe_push_cleanup_level (type);
6453 /* Don't push unnamed temps. Do set DECL_CONTEXT, though. */
6454 DECL_CONTEXT (var) = current_function_decl;
6460 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6461 initializing a variable of that TYPE. If DECL is non-NULL, it is
6462 the VAR_DECL being initialized with the EXPR. (In that case, the
6463 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6464 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6465 return, if *CLEANUP is no longer NULL, it will be an expression
6466 that should be pushed as a cleanup after the returned expression
6467 is used to initialize DECL.
6469 Return the converted expression. */
6472 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6477 if (type == error_mark_node || error_operand_p (expr))
6478 return error_mark_node;
6480 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6481 p = conversion_obstack_alloc (0);
6483 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6484 if (!conv || conv->bad_p)
6486 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6487 && !real_lvalue_p (expr))
6488 error ("invalid initialization of non-const reference of "
6489 "type %qT from a temporary of type %qT",
6490 type, TREE_TYPE (expr));
6492 error ("invalid initialization of reference of type "
6493 "%qT from expression of type %qT", type,
6495 return error_mark_node;
6498 /* If DECL is non-NULL, then this special rule applies:
6502 The temporary to which the reference is bound or the temporary
6503 that is the complete object to which the reference is bound
6504 persists for the lifetime of the reference.
6506 The temporaries created during the evaluation of the expression
6507 initializing the reference, except the temporary to which the
6508 reference is bound, are destroyed at the end of the
6509 full-expression in which they are created.
6511 In that case, we store the converted expression into a new
6512 VAR_DECL in a new scope.
6514 However, we want to be careful not to create temporaries when
6515 they are not required. For example, given:
6518 struct D : public B {};
6522 there is no need to copy the return value from "f"; we can just
6523 extend its lifetime. Similarly, given:
6526 struct T { operator S(); };
6530 we can extend the lifetime of the return value of the conversion
6532 gcc_assert (conv->kind == ck_ref_bind);
6536 tree base_conv_type;
6538 /* Skip over the REF_BIND. */
6539 conv = conv->u.next;
6540 /* If the next conversion is a BASE_CONV, skip that too -- but
6541 remember that the conversion was required. */
6542 if (conv->kind == ck_base)
6544 if (conv->check_copy_constructor_p)
6545 check_constructor_callable (TREE_TYPE (expr), expr);
6546 base_conv_type = conv->type;
6547 conv = conv->u.next;
6550 base_conv_type = NULL_TREE;
6551 /* Perform the remainder of the conversion. */
6552 expr = convert_like_real (conv, expr,
6553 /*fn=*/NULL_TREE, /*argnum=*/0,
6555 /*issue_conversion_warnings=*/true,
6556 /*c_cast_p=*/false);
6557 if (error_operand_p (expr))
6558 expr = error_mark_node;
6561 if (!real_lvalue_p (expr))
6566 /* Create the temporary variable. */
6567 type = TREE_TYPE (expr);
6568 var = make_temporary_var_for_ref_to_temp (decl, type);
6569 layout_decl (var, 0);
6570 /* If the rvalue is the result of a function call it will be
6571 a TARGET_EXPR. If it is some other construct (such as a
6572 member access expression where the underlying object is
6573 itself the result of a function call), turn it into a
6574 TARGET_EXPR here. It is important that EXPR be a
6575 TARGET_EXPR below since otherwise the INIT_EXPR will
6576 attempt to make a bitwise copy of EXPR to initialize
6578 if (TREE_CODE (expr) != TARGET_EXPR)
6579 expr = get_target_expr (expr);
6580 /* Create the INIT_EXPR that will initialize the temporary
6582 init = build2 (INIT_EXPR, type, var, expr);
6583 if (at_function_scope_p ())
6585 add_decl_expr (var);
6586 *cleanup = cxx_maybe_build_cleanup (var);
6588 /* We must be careful to destroy the temporary only
6589 after its initialization has taken place. If the
6590 initialization throws an exception, then the
6591 destructor should not be run. We cannot simply
6592 transform INIT into something like:
6594 (INIT, ({ CLEANUP_STMT; }))
6596 because emit_local_var always treats the
6597 initializer as a full-expression. Thus, the
6598 destructor would run too early; it would run at the
6599 end of initializing the reference variable, rather
6600 than at the end of the block enclosing the
6603 The solution is to pass back a cleanup expression
6604 which the caller is responsible for attaching to
6605 the statement tree. */
6609 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
6610 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6611 static_aggregates = tree_cons (NULL_TREE, var,
6614 /* Use its address to initialize the reference variable. */
6615 expr = build_address (var);
6617 expr = convert_to_base (expr,
6618 build_pointer_type (base_conv_type),
6619 /*check_access=*/true,
6621 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6624 /* Take the address of EXPR. */
6625 expr = build_unary_op (ADDR_EXPR, expr, 0);
6626 /* If a BASE_CONV was required, perform it now. */
6628 expr = (perform_implicit_conversion
6629 (build_pointer_type (base_conv_type), expr));
6630 expr = build_nop (type, expr);
6634 /* Perform the conversion. */
6635 expr = convert_like (conv, expr);
6637 /* Free all the conversions we allocated. */
6638 obstack_free (&conversion_obstack, p);
6643 #include "gt-cp-call.h"