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 gcc_assert (TYPE_PTR_P (TREE_TYPE (function)));
288 fntype = TREE_TYPE (TREE_TYPE (function));
289 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
290 || TREE_CODE (fntype) == METHOD_TYPE);
291 result_type = TREE_TYPE (fntype);
293 if (TREE_CODE (function) == ADDR_EXPR
294 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
296 decl = TREE_OPERAND (function, 0);
297 if (!TREE_USED (decl))
299 /* We invoke build_call directly for several library
300 functions. These may have been declared normally if
301 we're building libgcc, so we can't just check
303 gcc_assert (DECL_ARTIFICIAL (decl)
304 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)),
312 /* We check both the decl and the type; a function may be known not to
313 throw without being declared throw(). */
314 nothrow = ((decl && TREE_NOTHROW (decl))
315 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
317 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
318 current_function_returns_abnormally = 1;
320 if (decl && TREE_DEPRECATED (decl))
321 warn_deprecated_use (decl);
322 require_complete_eh_spec_types (fntype, decl);
324 if (decl && DECL_CONSTRUCTOR_P (decl))
327 /* Don't pass empty class objects by value. This is useful
328 for tags in STL, which are used to control overload resolution.
329 We don't need to handle other cases of copying empty classes. */
330 if (! decl || ! DECL_BUILT_IN (decl))
331 for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
332 if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
333 && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
335 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
336 TREE_VALUE (tmp) = build2 (COMPOUND_EXPR, TREE_TYPE (t),
337 TREE_VALUE (tmp), t);
340 function = build3 (CALL_EXPR, result_type, function, parms, NULL_TREE);
341 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
342 TREE_NOTHROW (function) = nothrow;
347 /* Build something of the form ptr->method (args)
348 or object.method (args). This can also build
349 calls to constructors, and find friends.
351 Member functions always take their class variable
354 INSTANCE is a class instance.
356 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
358 PARMS help to figure out what that NAME really refers to.
360 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
361 down to the real instance type to use for access checking. We need this
362 information to get protected accesses correct.
364 FLAGS is the logical disjunction of zero or more LOOKUP_
365 flags. See cp-tree.h for more info.
367 If this is all OK, calls build_function_call with the resolved
370 This function must also handle being called to perform
371 initialization, promotion/coercion of arguments, and
372 instantiation of default parameters.
374 Note that NAME may refer to an instance variable name. If
375 `operator()()' is defined for the type of that field, then we return
378 /* New overloading code. */
380 typedef struct z_candidate z_candidate;
382 typedef struct candidate_warning candidate_warning;
383 struct candidate_warning {
385 candidate_warning *next;
389 /* The FUNCTION_DECL that will be called if this candidate is
390 selected by overload resolution. */
392 /* The arguments to use when calling this function. */
394 /* The implicit conversion sequences for each of the arguments to
397 /* The number of implicit conversion sequences. */
399 /* If FN is a user-defined conversion, the standard conversion
400 sequence from the type returned by FN to the desired destination
402 conversion *second_conv;
404 /* If FN is a member function, the binfo indicating the path used to
405 qualify the name of FN at the call site. This path is used to
406 determine whether or not FN is accessible if it is selected by
407 overload resolution. The DECL_CONTEXT of FN will always be a
408 (possibly improper) base of this binfo. */
410 /* If FN is a non-static member function, the binfo indicating the
411 subobject to which the `this' pointer should be converted if FN
412 is selected by overload resolution. The type pointed to the by
413 the `this' pointer must correspond to the most derived class
414 indicated by the CONVERSION_PATH. */
415 tree conversion_path;
417 candidate_warning *warnings;
421 /* Returns true iff T is a null pointer constant in the sense of
425 null_ptr_cst_p (tree t)
429 A null pointer constant is an integral constant expression
430 (_expr.const_) rvalue of integer type that evaluates to zero. */
431 t = integral_constant_value (t);
433 || (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
438 /* Returns nonzero if PARMLIST consists of only default parms and/or
442 sufficient_parms_p (tree parmlist)
444 for (; parmlist && parmlist != void_list_node;
445 parmlist = TREE_CHAIN (parmlist))
446 if (!TREE_PURPOSE (parmlist))
451 /* Allocate N bytes of memory from the conversion obstack. The memory
452 is zeroed before being returned. */
455 conversion_obstack_alloc (size_t n)
458 if (!conversion_obstack_initialized)
460 gcc_obstack_init (&conversion_obstack);
461 conversion_obstack_initialized = true;
463 p = obstack_alloc (&conversion_obstack, n);
468 /* Dynamically allocate a conversion. */
471 alloc_conversion (conversion_kind kind)
474 c = conversion_obstack_alloc (sizeof (conversion));
479 #ifdef ENABLE_CHECKING
481 /* Make sure that all memory on the conversion obstack has been
485 validate_conversion_obstack (void)
487 if (conversion_obstack_initialized)
488 gcc_assert ((obstack_next_free (&conversion_obstack)
489 == obstack_base (&conversion_obstack)));
492 #endif /* ENABLE_CHECKING */
494 /* Dynamically allocate an array of N conversions. */
497 alloc_conversions (size_t n)
499 return conversion_obstack_alloc (n * sizeof (conversion *));
503 build_conv (conversion_kind code, tree type, conversion *from)
506 conversion_rank rank = CONVERSION_RANK (from);
508 /* We can't use buildl1 here because CODE could be USER_CONV, which
509 takes two arguments. In that case, the caller is responsible for
510 filling in the second argument. */
511 t = alloc_conversion (code);
534 t->user_conv_p = (code == ck_user || from->user_conv_p);
535 t->bad_p = from->bad_p;
540 /* Build a representation of the identity conversion from EXPR to
541 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
544 build_identity_conv (tree type, tree expr)
548 c = alloc_conversion (ck_identity);
555 /* Converting from EXPR to TYPE was ambiguous in the sense that there
556 were multiple user-defined conversions to accomplish the job.
557 Build a conversion that indicates that ambiguity. */
560 build_ambiguous_conv (tree type, tree expr)
564 c = alloc_conversion (ck_ambig);
572 strip_top_quals (tree t)
574 if (TREE_CODE (t) == ARRAY_TYPE)
576 return cp_build_qualified_type (t, 0);
579 /* Returns the standard conversion path (see [conv]) from type FROM to type
580 TO, if any. For proper handling of null pointer constants, you must
581 also pass the expression EXPR to convert from. If C_CAST_P is true,
582 this conversion is coming from a C-style cast. */
585 standard_conversion (tree to, tree from, tree expr, bool c_cast_p,
588 enum tree_code fcode, tcode;
590 bool fromref = false;
592 to = non_reference (to);
593 if (TREE_CODE (from) == REFERENCE_TYPE)
596 from = TREE_TYPE (from);
598 to = strip_top_quals (to);
599 from = strip_top_quals (from);
601 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
602 && expr && type_unknown_p (expr))
604 expr = instantiate_type (to, expr, tf_conv);
605 if (expr == error_mark_node)
607 from = TREE_TYPE (expr);
610 fcode = TREE_CODE (from);
611 tcode = TREE_CODE (to);
613 conv = build_identity_conv (from, expr);
614 if (fcode == FUNCTION_TYPE)
616 from = build_pointer_type (from);
617 fcode = TREE_CODE (from);
618 conv = build_conv (ck_lvalue, from, conv);
620 else if (fcode == ARRAY_TYPE)
622 from = build_pointer_type (TREE_TYPE (from));
623 fcode = TREE_CODE (from);
624 conv = build_conv (ck_lvalue, from, conv);
626 else if (fromref || (expr && lvalue_p (expr)))
627 conv = build_conv (ck_rvalue, from, conv);
629 /* Allow conversion between `__complex__' data types. */
630 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
632 /* The standard conversion sequence to convert FROM to TO is
633 the standard conversion sequence to perform componentwise
635 conversion *part_conv = standard_conversion
636 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE, c_cast_p, flags);
640 conv = build_conv (part_conv->kind, to, conv);
641 conv->rank = part_conv->rank;
649 if (same_type_p (from, to))
652 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
653 && expr && null_ptr_cst_p (expr))
654 conv = build_conv (ck_std, to, conv);
655 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
656 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
658 /* For backwards brain damage compatibility, allow interconversion of
659 pointers and integers with a pedwarn. */
660 conv = build_conv (ck_std, to, conv);
663 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
665 /* For backwards brain damage compatibility, allow interconversion of
666 enums and integers with a pedwarn. */
667 conv = build_conv (ck_std, to, conv);
670 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
671 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
676 if (tcode == POINTER_TYPE
677 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
680 else if (VOID_TYPE_P (TREE_TYPE (to))
681 && !TYPE_PTRMEM_P (from)
682 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
684 from = build_pointer_type
685 (cp_build_qualified_type (void_type_node,
686 cp_type_quals (TREE_TYPE (from))));
687 conv = build_conv (ck_ptr, from, conv);
689 else if (TYPE_PTRMEM_P (from))
691 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
692 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
694 if (DERIVED_FROM_P (fbase, tbase)
695 && (same_type_ignoring_top_level_qualifiers_p
696 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
697 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
699 from = build_ptrmem_type (tbase,
700 TYPE_PTRMEM_POINTED_TO_TYPE (from));
701 conv = build_conv (ck_pmem, from, conv);
703 else if (!same_type_p (fbase, tbase))
706 else if (IS_AGGR_TYPE (TREE_TYPE (from))
707 && IS_AGGR_TYPE (TREE_TYPE (to))
710 An rvalue of type "pointer to cv D," where D is a
711 class type, can be converted to an rvalue of type
712 "pointer to cv B," where B is a base class (clause
713 _class.derived_) of D. If B is an inaccessible
714 (clause _class.access_) or ambiguous
715 (_class.member.lookup_) base class of D, a program
716 that necessitates this conversion is ill-formed.
717 Therefore, we use DERIVED_FROM_P, and do not check
718 access or uniqueness. */
719 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
722 cp_build_qualified_type (TREE_TYPE (to),
723 cp_type_quals (TREE_TYPE (from)));
724 from = build_pointer_type (from);
725 conv = build_conv (ck_ptr, from, conv);
729 if (tcode == POINTER_TYPE)
731 to_pointee = TREE_TYPE (to);
732 from_pointee = TREE_TYPE (from);
736 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
737 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
740 if (same_type_p (from, to))
742 else if (c_cast_p && comp_ptr_ttypes_const (to, from))
743 /* In a C-style cast, we ignore CV-qualification because we
744 are allowed to perform a static_cast followed by a
746 conv = build_conv (ck_qual, to, conv);
747 else if (!c_cast_p && comp_ptr_ttypes (to_pointee, from_pointee))
748 conv = build_conv (ck_qual, to, conv);
749 else if (expr && string_conv_p (to, expr, 0))
750 /* converting from string constant to char *. */
751 conv = build_conv (ck_qual, to, conv);
752 else if (ptr_reasonably_similar (to_pointee, from_pointee))
754 conv = build_conv (ck_ptr, to, conv);
762 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
764 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
765 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
766 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
767 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
769 if (!DERIVED_FROM_P (fbase, tbase)
770 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
771 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
772 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
773 || cp_type_quals (fbase) != cp_type_quals (tbase))
776 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
777 from = build_method_type_directly (from,
779 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
780 from = build_ptrmemfunc_type (build_pointer_type (from));
781 conv = build_conv (ck_pmem, from, conv);
784 else if (tcode == BOOLEAN_TYPE)
788 An rvalue of arithmetic, enumeration, pointer, or pointer to
789 member type can be converted to an rvalue of type bool. */
790 if (ARITHMETIC_TYPE_P (from)
791 || fcode == ENUMERAL_TYPE
792 || fcode == POINTER_TYPE
793 || TYPE_PTR_TO_MEMBER_P (from))
795 conv = build_conv (ck_std, to, conv);
796 if (fcode == POINTER_TYPE
797 || TYPE_PTRMEM_P (from)
798 || (TYPE_PTRMEMFUNC_P (from)
799 && conv->rank < cr_pbool))
800 conv->rank = cr_pbool;
806 /* We don't check for ENUMERAL_TYPE here because there are no standard
807 conversions to enum type. */
808 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
809 || tcode == REAL_TYPE)
811 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
813 conv = build_conv (ck_std, to, conv);
815 /* Give this a better rank if it's a promotion. */
816 if (same_type_p (to, type_promotes_to (from))
817 && conv->u.next->rank <= cr_promotion)
818 conv->rank = cr_promotion;
820 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
821 && vector_types_convertible_p (from, to))
822 return build_conv (ck_std, to, conv);
823 else if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE)
824 && IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
825 && is_properly_derived_from (from, to))
827 if (conv->kind == ck_rvalue)
829 conv = build_conv (ck_base, to, conv);
830 /* The derived-to-base conversion indicates the initialization
831 of a parameter with base type from an object of a derived
832 type. A temporary object is created to hold the result of
834 conv->need_temporary_p = true;
842 /* Returns nonzero if T1 is reference-related to T2. */
845 reference_related_p (tree t1, tree t2)
847 t1 = TYPE_MAIN_VARIANT (t1);
848 t2 = TYPE_MAIN_VARIANT (t2);
852 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
853 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
855 return (same_type_p (t1, t2)
856 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
857 && DERIVED_FROM_P (t1, t2)));
860 /* Returns nonzero if T1 is reference-compatible with T2. */
863 reference_compatible_p (tree t1, tree t2)
867 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
868 reference-related to T2 and cv1 is the same cv-qualification as,
869 or greater cv-qualification than, cv2. */
870 return (reference_related_p (t1, t2)
871 && at_least_as_qualified_p (t1, t2));
874 /* Determine whether or not the EXPR (of class type S) can be
875 converted to T as in [over.match.ref]. */
878 convert_class_to_reference (tree t, tree s, tree expr)
884 struct z_candidate *candidates;
885 struct z_candidate *cand;
888 conversions = lookup_conversions (s);
894 Assuming that "cv1 T" is the underlying type of the reference
895 being initialized, and "cv S" is the type of the initializer
896 expression, with S a class type, the candidate functions are
899 --The conversion functions of S and its base classes are
900 considered. Those that are not hidden within S and yield type
901 "reference to cv2 T2", where "cv1 T" is reference-compatible
902 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
904 The argument list has one argument, which is the initializer
909 /* Conceptually, we should take the address of EXPR and put it in
910 the argument list. Unfortunately, however, that can result in
911 error messages, which we should not issue now because we are just
912 trying to find a conversion operator. Therefore, we use NULL,
913 cast to the appropriate type. */
914 arglist = build_int_cst (build_pointer_type (s), 0);
915 arglist = build_tree_list (NULL_TREE, arglist);
917 reference_type = build_reference_type (t);
921 tree fns = TREE_VALUE (conversions);
923 for (; fns; fns = OVL_NEXT (fns))
925 tree f = OVL_CURRENT (fns);
926 tree t2 = TREE_TYPE (TREE_TYPE (f));
930 /* If this is a template function, try to get an exact
932 if (TREE_CODE (f) == TEMPLATE_DECL)
934 cand = add_template_candidate (&candidates,
940 TREE_PURPOSE (conversions),
946 /* Now, see if the conversion function really returns
947 an lvalue of the appropriate type. From the
948 point of view of unification, simply returning an
949 rvalue of the right type is good enough. */
951 t2 = TREE_TYPE (TREE_TYPE (f));
952 if (TREE_CODE (t2) != REFERENCE_TYPE
953 || !reference_compatible_p (t, TREE_TYPE (t2)))
955 candidates = candidates->next;
960 else if (TREE_CODE (t2) == REFERENCE_TYPE
961 && reference_compatible_p (t, TREE_TYPE (t2)))
962 cand = add_function_candidate (&candidates, f, s, arglist,
964 TREE_PURPOSE (conversions),
969 conversion *identity_conv;
970 /* Build a standard conversion sequence indicating the
971 binding from the reference type returned by the
972 function to the desired REFERENCE_TYPE. */
974 = build_identity_conv (TREE_TYPE (TREE_TYPE
975 (TREE_TYPE (cand->fn))),
978 = (direct_reference_binding
979 (reference_type, identity_conv));
980 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
983 conversions = TREE_CHAIN (conversions);
986 candidates = splice_viable (candidates, pedantic, &any_viable_p);
987 /* If none of the conversion functions worked out, let our caller
992 cand = tourney (candidates);
996 /* Now that we know that this is the function we're going to use fix
997 the dummy first argument. */
998 cand->args = tree_cons (NULL_TREE,
1000 TREE_CHAIN (cand->args));
1002 /* Build a user-defined conversion sequence representing the
1004 conv = build_conv (ck_user,
1005 TREE_TYPE (TREE_TYPE (cand->fn)),
1006 build_identity_conv (TREE_TYPE (expr), expr));
1009 /* Merge it with the standard conversion sequence from the
1010 conversion function's return type to the desired type. */
1011 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1013 if (cand->viable == -1)
1016 return cand->second_conv;
1019 /* A reference of the indicated TYPE is being bound directly to the
1020 expression represented by the implicit conversion sequence CONV.
1021 Return a conversion sequence for this binding. */
1024 direct_reference_binding (tree type, conversion *conv)
1028 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
1029 gcc_assert (TREE_CODE (conv->type) != REFERENCE_TYPE);
1031 t = TREE_TYPE (type);
1035 When a parameter of reference type binds directly
1036 (_dcl.init.ref_) to an argument expression, the implicit
1037 conversion sequence is the identity conversion, unless the
1038 argument expression has a type that is a derived class of the
1039 parameter type, in which case the implicit conversion sequence is
1040 a derived-to-base Conversion.
1042 If the parameter binds directly to the result of applying a
1043 conversion function to the argument expression, the implicit
1044 conversion sequence is a user-defined conversion sequence
1045 (_over.ics.user_), with the second standard conversion sequence
1046 either an identity conversion or, if the conversion function
1047 returns an entity of a type that is a derived class of the
1048 parameter type, a derived-to-base conversion. */
1049 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1051 /* Represent the derived-to-base conversion. */
1052 conv = build_conv (ck_base, t, conv);
1053 /* We will actually be binding to the base-class subobject in
1054 the derived class, so we mark this conversion appropriately.
1055 That way, convert_like knows not to generate a temporary. */
1056 conv->need_temporary_p = false;
1058 return build_conv (ck_ref_bind, type, conv);
1061 /* Returns the conversion path from type FROM to reference type TO for
1062 purposes of reference binding. For lvalue binding, either pass a
1063 reference type to FROM or an lvalue expression to EXPR. If the
1064 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1065 the conversion returned. */
1068 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1070 conversion *conv = NULL;
1071 tree to = TREE_TYPE (rto);
1075 cp_lvalue_kind lvalue_p = clk_none;
1077 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1079 expr = instantiate_type (to, expr, tf_none);
1080 if (expr == error_mark_node)
1082 from = TREE_TYPE (expr);
1085 if (TREE_CODE (from) == REFERENCE_TYPE)
1087 /* Anything with reference type is an lvalue. */
1088 lvalue_p = clk_ordinary;
1089 from = TREE_TYPE (from);
1092 lvalue_p = real_lvalue_p (expr);
1094 /* Figure out whether or not the types are reference-related and
1095 reference compatible. We have do do this after stripping
1096 references from FROM. */
1097 related_p = reference_related_p (to, from);
1098 compatible_p = reference_compatible_p (to, from);
1100 if (lvalue_p && compatible_p)
1104 If the initializer expression
1106 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1107 is reference-compatible with "cv2 T2,"
1109 the reference is bound directly to the initializer expression
1111 conv = build_identity_conv (from, expr);
1112 conv = direct_reference_binding (rto, conv);
1113 if ((lvalue_p & clk_bitfield) != 0
1114 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1115 /* For the purposes of overload resolution, we ignore the fact
1116 this expression is a bitfield or packed field. (In particular,
1117 [over.ics.ref] says specifically that a function with a
1118 non-const reference parameter is viable even if the
1119 argument is a bitfield.)
1121 However, when we actually call the function we must create
1122 a temporary to which to bind the reference. If the
1123 reference is volatile, or isn't const, then we cannot make
1124 a temporary, so we just issue an error when the conversion
1126 conv->need_temporary_p = true;
1130 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1134 If the initializer expression
1136 -- has a class type (i.e., T2 is a class type) can be
1137 implicitly converted to an lvalue of type "cv3 T3," where
1138 "cv1 T1" is reference-compatible with "cv3 T3". (this
1139 conversion is selected by enumerating the applicable
1140 conversion functions (_over.match.ref_) and choosing the
1141 best one through overload resolution. (_over.match_).
1143 the reference is bound to the lvalue result of the conversion
1144 in the second case. */
1145 conv = convert_class_to_reference (to, from, expr);
1150 /* From this point on, we conceptually need temporaries, even if we
1151 elide them. Only the cases above are "direct bindings". */
1152 if (flags & LOOKUP_NO_TEMP_BIND)
1157 When a parameter of reference type is not bound directly to an
1158 argument expression, the conversion sequence is the one required
1159 to convert the argument expression to the underlying type of the
1160 reference according to _over.best.ics_. Conceptually, this
1161 conversion sequence corresponds to copy-initializing a temporary
1162 of the underlying type with the argument expression. Any
1163 difference in top-level cv-qualification is subsumed by the
1164 initialization itself and does not constitute a conversion. */
1168 Otherwise, the reference shall be to a non-volatile const type. */
1169 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1174 If the initializer expression is an rvalue, with T2 a class type,
1175 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1176 is bound in one of the following ways:
1178 -- The reference is bound to the object represented by the rvalue
1179 or to a sub-object within that object.
1183 We use the first alternative. The implicit conversion sequence
1184 is supposed to be same as we would obtain by generating a
1185 temporary. Fortunately, if the types are reference compatible,
1186 then this is either an identity conversion or the derived-to-base
1187 conversion, just as for direct binding. */
1188 if (CLASS_TYPE_P (from) && compatible_p)
1190 conv = build_identity_conv (from, expr);
1191 conv = direct_reference_binding (rto, conv);
1192 if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
1193 conv->u.next->check_copy_constructor_p = true;
1199 Otherwise, a temporary of type "cv1 T1" is created and
1200 initialized from the initializer expression using the rules for a
1201 non-reference copy initialization. If T1 is reference-related to
1202 T2, cv1 must be the same cv-qualification as, or greater
1203 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1204 if (related_p && !at_least_as_qualified_p (to, from))
1207 conv = implicit_conversion (to, from, expr, /*c_cast_p=*/false,
1212 conv = build_conv (ck_ref_bind, rto, conv);
1213 /* This reference binding, unlike those above, requires the
1214 creation of a temporary. */
1215 conv->need_temporary_p = true;
1220 /* Returns the implicit conversion sequence (see [over.ics]) from type
1221 FROM to type TO. The optional expression EXPR may affect the
1222 conversion. FLAGS are the usual overloading flags. Only
1223 LOOKUP_NO_CONVERSION is significant. If C_CAST_P is true, this
1224 conversion is coming from a C-style cast. */
1227 implicit_conversion (tree to, tree from, tree expr, bool c_cast_p,
1232 if (from == error_mark_node || to == error_mark_node
1233 || expr == error_mark_node)
1236 if (TREE_CODE (to) == REFERENCE_TYPE)
1237 conv = reference_binding (to, from, expr, flags);
1239 conv = standard_conversion (to, from, expr, c_cast_p, flags);
1244 if (expr != NULL_TREE
1245 && (IS_AGGR_TYPE (from)
1246 || IS_AGGR_TYPE (to))
1247 && (flags & LOOKUP_NO_CONVERSION) == 0)
1249 struct z_candidate *cand;
1251 cand = build_user_type_conversion_1
1252 (to, expr, LOOKUP_ONLYCONVERTING);
1254 conv = cand->second_conv;
1256 /* We used to try to bind a reference to a temporary here, but that
1257 is now handled by the recursive call to this function at the end
1258 of reference_binding. */
1265 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1268 static struct z_candidate *
1269 add_candidate (struct z_candidate **candidates,
1271 size_t num_convs, conversion **convs,
1272 tree access_path, tree conversion_path,
1275 struct z_candidate *cand
1276 = conversion_obstack_alloc (sizeof (struct z_candidate));
1280 cand->convs = convs;
1281 cand->num_convs = num_convs;
1282 cand->access_path = access_path;
1283 cand->conversion_path = conversion_path;
1284 cand->viable = viable;
1285 cand->next = *candidates;
1291 /* Create an overload candidate for the function or method FN called with
1292 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1293 to implicit_conversion.
1295 CTYPE, if non-NULL, is the type we want to pretend this function
1296 comes from for purposes of overload resolution. */
1298 static struct z_candidate *
1299 add_function_candidate (struct z_candidate **candidates,
1300 tree fn, tree ctype, tree arglist,
1301 tree access_path, tree conversion_path,
1304 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1307 tree parmnode, argnode;
1311 /* At this point we should not see any functions which haven't been
1312 explicitly declared, except for friend functions which will have
1313 been found using argument dependent lookup. */
1314 gcc_assert (!DECL_ANTICIPATED (fn) || DECL_HIDDEN_FRIEND_P (fn));
1316 /* The `this', `in_chrg' and VTT arguments to constructors are not
1317 considered in overload resolution. */
1318 if (DECL_CONSTRUCTOR_P (fn))
1320 parmlist = skip_artificial_parms_for (fn, parmlist);
1321 orig_arglist = arglist;
1322 arglist = skip_artificial_parms_for (fn, arglist);
1325 orig_arglist = arglist;
1327 len = list_length (arglist);
1328 convs = alloc_conversions (len);
1330 /* 13.3.2 - Viable functions [over.match.viable]
1331 First, to be a viable function, a candidate function shall have enough
1332 parameters to agree in number with the arguments in the list.
1334 We need to check this first; otherwise, checking the ICSes might cause
1335 us to produce an ill-formed template instantiation. */
1337 parmnode = parmlist;
1338 for (i = 0; i < len; ++i)
1340 if (parmnode == NULL_TREE || parmnode == void_list_node)
1342 parmnode = TREE_CHAIN (parmnode);
1345 if (i < len && parmnode)
1348 /* Make sure there are default args for the rest of the parms. */
1349 else if (!sufficient_parms_p (parmnode))
1355 /* Second, for F to be a viable function, there shall exist for each
1356 argument an implicit conversion sequence that converts that argument
1357 to the corresponding parameter of F. */
1359 parmnode = parmlist;
1362 for (i = 0; i < len; ++i)
1364 tree arg = TREE_VALUE (argnode);
1365 tree argtype = lvalue_type (arg);
1369 if (parmnode == void_list_node)
1372 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1373 && ! DECL_CONSTRUCTOR_P (fn));
1377 tree parmtype = TREE_VALUE (parmnode);
1379 /* The type of the implicit object parameter ('this') for
1380 overload resolution is not always the same as for the
1381 function itself; conversion functions are considered to
1382 be members of the class being converted, and functions
1383 introduced by a using-declaration are considered to be
1384 members of the class that uses them.
1386 Since build_over_call ignores the ICS for the `this'
1387 parameter, we can just change the parm type. */
1388 if (ctype && is_this)
1391 = build_qualified_type (ctype,
1392 TYPE_QUALS (TREE_TYPE (parmtype)));
1393 parmtype = build_pointer_type (parmtype);
1396 t = implicit_conversion (parmtype, argtype, arg,
1397 /*c_cast_p=*/false, flags);
1401 t = build_identity_conv (argtype, arg);
1402 t->ellipsis_p = true;
1419 parmnode = TREE_CHAIN (parmnode);
1420 argnode = TREE_CHAIN (argnode);
1424 return add_candidate (candidates, fn, orig_arglist, len, convs,
1425 access_path, conversion_path, viable);
1428 /* Create an overload candidate for the conversion function FN which will
1429 be invoked for expression OBJ, producing a pointer-to-function which
1430 will in turn be called with the argument list ARGLIST, and add it to
1431 CANDIDATES. FLAGS is passed on to implicit_conversion.
1433 Actually, we don't really care about FN; we care about the type it
1434 converts to. There may be multiple conversion functions that will
1435 convert to that type, and we rely on build_user_type_conversion_1 to
1436 choose the best one; so when we create our candidate, we record the type
1437 instead of the function. */
1439 static struct z_candidate *
1440 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1441 tree arglist, tree access_path, tree conversion_path)
1443 tree totype = TREE_TYPE (TREE_TYPE (fn));
1444 int i, len, viable, flags;
1445 tree parmlist, parmnode, argnode;
1448 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1449 parmlist = TREE_TYPE (parmlist);
1450 parmlist = TYPE_ARG_TYPES (parmlist);
1452 len = list_length (arglist) + 1;
1453 convs = alloc_conversions (len);
1454 parmnode = parmlist;
1457 flags = LOOKUP_NORMAL;
1459 /* Don't bother looking up the same type twice. */
1460 if (*candidates && (*candidates)->fn == totype)
1463 for (i = 0; i < len; ++i)
1465 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1466 tree argtype = lvalue_type (arg);
1470 t = implicit_conversion (totype, argtype, arg, /*c_cast_p=*/false,
1472 else if (parmnode == void_list_node)
1475 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg,
1476 /*c_cast_p=*/false, flags);
1479 t = build_identity_conv (argtype, arg);
1480 t->ellipsis_p = true;
1494 parmnode = TREE_CHAIN (parmnode);
1495 argnode = TREE_CHAIN (argnode);
1501 if (!sufficient_parms_p (parmnode))
1504 return add_candidate (candidates, totype, arglist, len, convs,
1505 access_path, conversion_path, viable);
1509 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1510 tree type1, tree type2, tree *args, tree *argtypes,
1522 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1523 convs = alloc_conversions (num_convs);
1525 for (i = 0; i < 2; ++i)
1530 t = implicit_conversion (types[i], argtypes[i], args[i],
1531 /*c_cast_p=*/false, flags);
1535 /* We need something for printing the candidate. */
1536 t = build_identity_conv (types[i], NULL_TREE);
1543 /* For COND_EXPR we rearranged the arguments; undo that now. */
1546 convs[2] = convs[1];
1547 convs[1] = convs[0];
1548 t = implicit_conversion (boolean_type_node, argtypes[2], args[2],
1549 /*c_cast_p=*/false, flags);
1556 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1558 /*access_path=*/NULL_TREE,
1559 /*conversion_path=*/NULL_TREE,
1564 is_complete (tree t)
1566 return COMPLETE_TYPE_P (complete_type (t));
1569 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1572 promoted_arithmetic_type_p (tree type)
1576 In this section, the term promoted integral type is used to refer
1577 to those integral types which are preserved by integral promotion
1578 (including e.g. int and long but excluding e.g. char).
1579 Similarly, the term promoted arithmetic type refers to promoted
1580 integral types plus floating types. */
1581 return ((INTEGRAL_TYPE_P (type)
1582 && same_type_p (type_promotes_to (type), type))
1583 || TREE_CODE (type) == REAL_TYPE);
1586 /* Create any builtin operator overload candidates for the operator in
1587 question given the converted operand types TYPE1 and TYPE2. The other
1588 args are passed through from add_builtin_candidates to
1589 build_builtin_candidate.
1591 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1592 If CODE is requires candidates operands of the same type of the kind
1593 of which TYPE1 and TYPE2 are, we add both candidates
1594 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1597 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1598 enum tree_code code2, tree fnname, tree type1,
1599 tree type2, tree *args, tree *argtypes, int flags)
1603 case POSTINCREMENT_EXPR:
1604 case POSTDECREMENT_EXPR:
1605 args[1] = integer_zero_node;
1606 type2 = integer_type_node;
1615 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1616 and VQ is either volatile or empty, there exist candidate operator
1617 functions of the form
1618 VQ T& operator++(VQ T&);
1619 T operator++(VQ T&, int);
1620 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1621 type other than bool, and VQ is either volatile or empty, there exist
1622 candidate operator functions of the form
1623 VQ T& operator--(VQ T&);
1624 T operator--(VQ T&, int);
1625 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1626 complete object type, and VQ is either volatile or empty, there exist
1627 candidate operator functions of the form
1628 T*VQ& operator++(T*VQ&);
1629 T*VQ& operator--(T*VQ&);
1630 T* operator++(T*VQ&, int);
1631 T* operator--(T*VQ&, int); */
1633 case POSTDECREMENT_EXPR:
1634 case PREDECREMENT_EXPR:
1635 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1637 case POSTINCREMENT_EXPR:
1638 case PREINCREMENT_EXPR:
1639 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1641 type1 = build_reference_type (type1);
1646 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1647 exist candidate operator functions of the form
1651 8 For every function type T, there exist candidate operator functions of
1653 T& operator*(T*); */
1656 if (TREE_CODE (type1) == POINTER_TYPE
1657 && (TYPE_PTROB_P (type1)
1658 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1662 /* 9 For every type T, there exist candidate operator functions of the form
1665 10For every promoted arithmetic type T, there exist candidate operator
1666 functions of the form
1670 case UNARY_PLUS_EXPR: /* unary + */
1671 if (TREE_CODE (type1) == POINTER_TYPE)
1674 if (ARITHMETIC_TYPE_P (type1))
1678 /* 11For every promoted integral type T, there exist candidate operator
1679 functions of the form
1683 if (INTEGRAL_TYPE_P (type1))
1687 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1688 is the same type as C2 or is a derived class of C2, T is a complete
1689 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1690 there exist candidate operator functions of the form
1691 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1692 where CV12 is the union of CV1 and CV2. */
1695 if (TREE_CODE (type1) == POINTER_TYPE
1696 && TYPE_PTR_TO_MEMBER_P (type2))
1698 tree c1 = TREE_TYPE (type1);
1699 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1701 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1702 && (TYPE_PTRMEMFUNC_P (type2)
1703 || is_complete (TYPE_PTRMEM_POINTED_TO_TYPE (type2))))
1708 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1709 didate operator functions of the form
1714 bool operator<(L, R);
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 where LR is the result of the usual arithmetic conversions between
1723 14For every pair of types T and I, where T is a cv-qualified or cv-
1724 unqualified complete object type and I is a promoted integral type,
1725 there exist candidate operator functions of the form
1726 T* operator+(T*, I);
1727 T& operator[](T*, I);
1728 T* operator-(T*, I);
1729 T* operator+(I, T*);
1730 T& operator[](I, T*);
1732 15For every T, where T is a pointer to complete object type, there exist
1733 candidate operator functions of the form112)
1734 ptrdiff_t operator-(T, T);
1736 16For every pointer or enumeration type T, there exist candidate operator
1737 functions of the form
1738 bool operator<(T, T);
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);
1745 17For every pointer to member type T, there exist candidate operator
1746 functions of the form
1747 bool operator==(T, T);
1748 bool operator!=(T, T); */
1751 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1753 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1755 type2 = ptrdiff_type_node;
1759 case TRUNC_DIV_EXPR:
1760 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1766 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1767 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1769 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1774 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1786 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1788 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1790 if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
1792 if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
1797 if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
1805 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1808 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1810 type1 = ptrdiff_type_node;
1813 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1815 type2 = ptrdiff_type_node;
1820 /* 18For every pair of promoted integral types L and R, there exist candi-
1821 date operator functions of the form
1828 where LR is the result of the usual arithmetic conversions between
1831 case TRUNC_MOD_EXPR:
1837 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1841 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1842 type, VQ is either volatile or empty, and R is a promoted arithmetic
1843 type, there exist candidate operator functions of the form
1844 VQ L& operator=(VQ L&, R);
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);
1850 20For every pair T, VQ), where T is any type and VQ is either volatile
1851 or empty, there exist candidate operator functions of the form
1852 T*VQ& operator=(T*VQ&, T*);
1854 21For every pair T, VQ), where T is a pointer to member type and VQ is
1855 either volatile or empty, there exist candidate operator functions of
1857 VQ T& operator=(VQ T&, T);
1859 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1860 unqualified complete object type, VQ is either volatile or empty, and
1861 I is a promoted integral type, there exist candidate operator func-
1863 T*VQ& operator+=(T*VQ&, I);
1864 T*VQ& operator-=(T*VQ&, I);
1866 23For every triple L, VQ, R), where L is an integral or enumeration
1867 type, VQ is either volatile or empty, and R is a promoted integral
1868 type, there exist candidate operator functions of the form
1870 VQ L& operator%=(VQ L&, R);
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); */
1882 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1884 type2 = ptrdiff_type_node;
1888 case TRUNC_DIV_EXPR:
1889 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1893 case TRUNC_MOD_EXPR:
1899 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1904 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1906 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1907 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1908 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1909 || ((TYPE_PTRMEMFUNC_P (type1)
1910 || TREE_CODE (type1) == POINTER_TYPE)
1911 && null_ptr_cst_p (args[1])))
1921 type1 = build_reference_type (type1);
1927 For every pair of promoted arithmetic types L and R, there
1928 exist candidate operator functions of the form
1930 LR operator?(bool, L, R);
1932 where LR is the result of the usual arithmetic conversions
1933 between types L and R.
1935 For every type T, where T is a pointer or pointer-to-member
1936 type, there exist candidate operator functions of the form T
1937 operator?(bool, T, T); */
1939 if (promoted_arithmetic_type_p (type1)
1940 && promoted_arithmetic_type_p (type2))
1944 /* Otherwise, the types should be pointers. */
1945 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
1946 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
1949 /* We don't check that the two types are the same; the logic
1950 below will actually create two candidates; one in which both
1951 parameter types are TYPE1, and one in which both parameter
1959 /* If we're dealing with two pointer types or two enumeral types,
1960 we need candidates for both of them. */
1961 if (type2 && !same_type_p (type1, type2)
1962 && TREE_CODE (type1) == TREE_CODE (type2)
1963 && (TREE_CODE (type1) == REFERENCE_TYPE
1964 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1965 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1966 || TYPE_PTRMEMFUNC_P (type1)
1967 || IS_AGGR_TYPE (type1)
1968 || TREE_CODE (type1) == ENUMERAL_TYPE))
1970 build_builtin_candidate
1971 (candidates, fnname, type1, type1, args, argtypes, flags);
1972 build_builtin_candidate
1973 (candidates, fnname, type2, type2, args, argtypes, flags);
1977 build_builtin_candidate
1978 (candidates, fnname, type1, type2, args, argtypes, flags);
1982 type_decays_to (tree type)
1984 if (TREE_CODE (type) == ARRAY_TYPE)
1985 return build_pointer_type (TREE_TYPE (type));
1986 if (TREE_CODE (type) == FUNCTION_TYPE)
1987 return build_pointer_type (type);
1991 /* There are three conditions of builtin candidates:
1993 1) bool-taking candidates. These are the same regardless of the input.
1994 2) pointer-pair taking candidates. These are generated for each type
1995 one of the input types converts to.
1996 3) arithmetic candidates. According to the standard, we should generate
1997 all of these, but I'm trying not to...
1999 Here we generate a superset of the possible candidates for this particular
2000 case. That is a subset of the full set the standard defines, plus some
2001 other cases which the standard disallows. add_builtin_candidate will
2002 filter out the invalid set. */
2005 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2006 enum tree_code code2, tree fnname, tree *args,
2011 tree type, argtypes[3];
2012 /* TYPES[i] is the set of possible builtin-operator parameter types
2013 we will consider for the Ith argument. These are represented as
2014 a TREE_LIST; the TREE_VALUE of each node is the potential
2018 for (i = 0; i < 3; ++i)
2021 argtypes[i] = lvalue_type (args[i]);
2023 argtypes[i] = NULL_TREE;
2028 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2029 and VQ is either volatile or empty, there exist candidate operator
2030 functions of the form
2031 VQ T& operator++(VQ T&); */
2033 case POSTINCREMENT_EXPR:
2034 case PREINCREMENT_EXPR:
2035 case POSTDECREMENT_EXPR:
2036 case PREDECREMENT_EXPR:
2041 /* 24There also exist candidate operator functions of the form
2042 bool operator!(bool);
2043 bool operator&&(bool, bool);
2044 bool operator||(bool, bool); */
2046 case TRUTH_NOT_EXPR:
2047 build_builtin_candidate
2048 (candidates, fnname, boolean_type_node,
2049 NULL_TREE, args, argtypes, flags);
2052 case TRUTH_ORIF_EXPR:
2053 case TRUTH_ANDIF_EXPR:
2054 build_builtin_candidate
2055 (candidates, fnname, boolean_type_node,
2056 boolean_type_node, args, argtypes, flags);
2078 types[0] = types[1] = NULL_TREE;
2080 for (i = 0; i < 2; ++i)
2084 else if (IS_AGGR_TYPE (argtypes[i]))
2088 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2091 convs = lookup_conversions (argtypes[i]);
2093 if (code == COND_EXPR)
2095 if (real_lvalue_p (args[i]))
2096 types[i] = tree_cons
2097 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2099 types[i] = tree_cons
2100 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2106 for (; convs; convs = TREE_CHAIN (convs))
2108 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2111 && (TREE_CODE (type) != REFERENCE_TYPE
2112 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2115 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2116 types[i] = tree_cons (NULL_TREE, type, types[i]);
2118 type = non_reference (type);
2119 if (i != 0 || ! ref1)
2121 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2122 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2123 types[i] = tree_cons (NULL_TREE, type, types[i]);
2124 if (INTEGRAL_TYPE_P (type))
2125 type = type_promotes_to (type);
2128 if (! value_member (type, types[i]))
2129 types[i] = tree_cons (NULL_TREE, type, types[i]);
2134 if (code == COND_EXPR && real_lvalue_p (args[i]))
2135 types[i] = tree_cons
2136 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2137 type = non_reference (argtypes[i]);
2138 if (i != 0 || ! ref1)
2140 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2141 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2142 types[i] = tree_cons (NULL_TREE, type, types[i]);
2143 if (INTEGRAL_TYPE_P (type))
2144 type = type_promotes_to (type);
2146 types[i] = tree_cons (NULL_TREE, type, types[i]);
2150 /* Run through the possible parameter types of both arguments,
2151 creating candidates with those parameter types. */
2152 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2155 for (type = types[1]; type; type = TREE_CHAIN (type))
2156 add_builtin_candidate
2157 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2158 TREE_VALUE (type), args, argtypes, flags);
2160 add_builtin_candidate
2161 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2162 NULL_TREE, args, argtypes, flags);
2169 /* If TMPL can be successfully instantiated as indicated by
2170 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2172 TMPL is the template. EXPLICIT_TARGS are any explicit template
2173 arguments. ARGLIST is the arguments provided at the call-site.
2174 The RETURN_TYPE is the desired type for conversion operators. If
2175 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2176 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2177 add_conv_candidate. */
2179 static struct z_candidate*
2180 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2181 tree ctype, tree explicit_targs, tree arglist,
2182 tree return_type, tree access_path,
2183 tree conversion_path, int flags, tree obj,
2184 unification_kind_t strict)
2186 int ntparms = DECL_NTPARMS (tmpl);
2187 tree targs = make_tree_vec (ntparms);
2188 tree args_without_in_chrg = arglist;
2189 struct z_candidate *cand;
2193 /* We don't do deduction on the in-charge parameter, the VTT
2194 parameter or 'this'. */
2195 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2196 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2198 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2199 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2200 && CLASSTYPE_VBASECLASSES (DECL_CONTEXT (tmpl)))
2201 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2203 i = fn_type_unification (tmpl, explicit_targs, targs,
2204 args_without_in_chrg,
2205 return_type, strict, flags);
2210 fn = instantiate_template (tmpl, targs, tf_none);
2211 if (fn == error_mark_node)
2216 A member function template is never instantiated to perform the
2217 copy of a class object to an object of its class type.
2219 It's a little unclear what this means; the standard explicitly
2220 does allow a template to be used to copy a class. For example,
2225 template <class T> A(const T&);
2228 void g () { A a (f ()); }
2230 the member template will be used to make the copy. The section
2231 quoted above appears in the paragraph that forbids constructors
2232 whose only parameter is (a possibly cv-qualified variant of) the
2233 class type, and a logical interpretation is that the intent was
2234 to forbid the instantiation of member templates which would then
2236 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2238 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2239 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2244 if (obj != NULL_TREE)
2245 /* Aha, this is a conversion function. */
2246 cand = add_conv_candidate (candidates, fn, obj, access_path,
2247 conversion_path, arglist);
2249 cand = add_function_candidate (candidates, fn, ctype,
2250 arglist, access_path,
2251 conversion_path, flags);
2252 if (DECL_TI_TEMPLATE (fn) != tmpl)
2253 /* This situation can occur if a member template of a template
2254 class is specialized. Then, instantiate_template might return
2255 an instantiation of the specialization, in which case the
2256 DECL_TI_TEMPLATE field will point at the original
2257 specialization. For example:
2259 template <class T> struct S { template <class U> void f(U);
2260 template <> void f(int) {}; };
2264 Here, TMPL will be template <class U> S<double>::f(U).
2265 And, instantiate template will give us the specialization
2266 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2267 for this will point at template <class T> template <> S<T>::f(int),
2268 so that we can find the definition. For the purposes of
2269 overload resolution, however, we want the original TMPL. */
2270 cand->template_decl = tree_cons (tmpl, targs, NULL_TREE);
2272 cand->template_decl = DECL_TEMPLATE_INFO (fn);
2278 static struct z_candidate *
2279 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2280 tree explicit_targs, tree arglist, tree return_type,
2281 tree access_path, tree conversion_path, int flags,
2282 unification_kind_t strict)
2285 add_template_candidate_real (candidates, tmpl, ctype,
2286 explicit_targs, arglist, return_type,
2287 access_path, conversion_path,
2288 flags, NULL_TREE, strict);
2292 static struct z_candidate *
2293 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2294 tree obj, tree arglist, tree return_type,
2295 tree access_path, tree conversion_path)
2298 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2299 arglist, return_type, access_path,
2300 conversion_path, 0, obj, DEDUCE_CONV);
2303 /* The CANDS are the set of candidates that were considered for
2304 overload resolution. Return the set of viable candidates. If none
2305 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2306 is true if a candidate should be considered viable only if it is
2309 static struct z_candidate*
2310 splice_viable (struct z_candidate *cands,
2314 struct z_candidate *viable;
2315 struct z_candidate **last_viable;
2316 struct z_candidate **cand;
2319 last_viable = &viable;
2320 *any_viable_p = false;
2325 struct z_candidate *c = *cand;
2326 if (strict_p ? c->viable == 1 : c->viable)
2331 last_viable = &c->next;
2332 *any_viable_p = true;
2338 return viable ? viable : cands;
2342 any_strictly_viable (struct z_candidate *cands)
2344 for (; cands; cands = cands->next)
2345 if (cands->viable == 1)
2350 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2351 words, it is about to become the "this" pointer for a member
2352 function call. Take the address of the object. */
2355 build_this (tree obj)
2357 /* In a template, we are only concerned about the type of the
2358 expression, so we can take a shortcut. */
2359 if (processing_template_decl)
2360 return build_address (obj);
2362 return build_unary_op (ADDR_EXPR, obj, 0);
2365 /* Returns true iff functions are equivalent. Equivalent functions are
2366 not '==' only if one is a function-local extern function or if
2367 both are extern "C". */
2370 equal_functions (tree fn1, tree fn2)
2372 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2373 || DECL_EXTERN_C_FUNCTION_P (fn1))
2374 return decls_match (fn1, fn2);
2378 /* Print information about one overload candidate CANDIDATE. MSGSTR
2379 is the text to print before the candidate itself.
2381 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2382 to have been run through gettext by the caller. This wart makes
2383 life simpler in print_z_candidates and for the translators. */
2386 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2388 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2390 if (candidate->num_convs == 3)
2391 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2392 candidate->convs[0]->type,
2393 candidate->convs[1]->type,
2394 candidate->convs[2]->type);
2395 else if (candidate->num_convs == 2)
2396 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2397 candidate->convs[0]->type,
2398 candidate->convs[1]->type);
2400 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2401 candidate->convs[0]->type);
2403 else if (TYPE_P (candidate->fn))
2404 inform ("%s %T <conversion>", msgstr, candidate->fn);
2405 else if (candidate->viable == -1)
2406 inform ("%s %+#D <near match>", msgstr, candidate->fn);
2408 inform ("%s %+#D", msgstr, candidate->fn);
2412 print_z_candidates (struct z_candidate *candidates)
2415 struct z_candidate *cand1;
2416 struct z_candidate **cand2;
2418 /* There may be duplicates in the set of candidates. We put off
2419 checking this condition as long as possible, since we have no way
2420 to eliminate duplicates from a set of functions in less than n^2
2421 time. Now we are about to emit an error message, so it is more
2422 permissible to go slowly. */
2423 for (cand1 = candidates; cand1; cand1 = cand1->next)
2425 tree fn = cand1->fn;
2426 /* Skip builtin candidates and conversion functions. */
2427 if (TREE_CODE (fn) != FUNCTION_DECL)
2429 cand2 = &cand1->next;
2432 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2433 && equal_functions (fn, (*cand2)->fn))
2434 *cand2 = (*cand2)->next;
2436 cand2 = &(*cand2)->next;
2443 str = _("candidates are:");
2444 print_z_candidate (str, candidates);
2445 if (candidates->next)
2447 /* Indent successive candidates by the width of the translation
2448 of the above string. */
2449 size_t len = gcc_gettext_width (str) + 1;
2450 char *spaces = alloca (len);
2451 memset (spaces, ' ', len-1);
2452 spaces[len - 1] = '\0';
2454 candidates = candidates->next;
2457 print_z_candidate (spaces, candidates);
2458 candidates = candidates->next;
2464 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2465 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2466 the result of the conversion function to convert it to the final
2467 desired type. Merge the two sequences into a single sequence,
2468 and return the merged sequence. */
2471 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2475 gcc_assert (user_seq->kind == ck_user);
2477 /* Find the end of the second conversion sequence. */
2479 while ((*t)->kind != ck_identity)
2480 t = &((*t)->u.next);
2482 /* Replace the identity conversion with the user conversion
2486 /* The entire sequence is a user-conversion sequence. */
2487 std_seq->user_conv_p = true;
2492 /* Returns the best overload candidate to perform the requested
2493 conversion. This function is used for three the overloading situations
2494 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2495 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2496 per [dcl.init.ref], so we ignore temporary bindings. */
2498 static struct z_candidate *
2499 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2501 struct z_candidate *candidates, *cand;
2502 tree fromtype = TREE_TYPE (expr);
2503 tree ctors = NULL_TREE;
2504 tree conv_fns = NULL_TREE;
2505 conversion *conv = NULL;
2506 tree args = NULL_TREE;
2509 /* We represent conversion within a hierarchy using RVALUE_CONV and
2510 BASE_CONV, as specified by [over.best.ics]; these become plain
2511 constructor calls, as specified in [dcl.init]. */
2512 gcc_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2513 || !DERIVED_FROM_P (totype, fromtype));
2515 if (IS_AGGR_TYPE (totype))
2516 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2518 if (IS_AGGR_TYPE (fromtype))
2519 conv_fns = lookup_conversions (fromtype);
2522 flags |= LOOKUP_NO_CONVERSION;
2528 ctors = BASELINK_FUNCTIONS (ctors);
2530 t = build_int_cst (build_pointer_type (totype), 0);
2531 args = build_tree_list (NULL_TREE, expr);
2532 /* We should never try to call the abstract or base constructor
2534 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2535 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)));
2536 args = tree_cons (NULL_TREE, t, args);
2538 for (; ctors; ctors = OVL_NEXT (ctors))
2540 tree ctor = OVL_CURRENT (ctors);
2541 if (DECL_NONCONVERTING_P (ctor))
2544 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2545 cand = add_template_candidate (&candidates, ctor, totype,
2546 NULL_TREE, args, NULL_TREE,
2547 TYPE_BINFO (totype),
2548 TYPE_BINFO (totype),
2552 cand = add_function_candidate (&candidates, ctor, totype,
2553 args, TYPE_BINFO (totype),
2554 TYPE_BINFO (totype),
2558 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2562 args = build_tree_list (NULL_TREE, build_this (expr));
2564 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2567 tree conversion_path = TREE_PURPOSE (conv_fns);
2568 int convflags = LOOKUP_NO_CONVERSION;
2570 /* If we are called to convert to a reference type, we are trying to
2571 find an lvalue binding, so don't even consider temporaries. If
2572 we don't find an lvalue binding, the caller will try again to
2573 look for a temporary binding. */
2574 if (TREE_CODE (totype) == REFERENCE_TYPE)
2575 convflags |= LOOKUP_NO_TEMP_BIND;
2577 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2579 tree fn = OVL_CURRENT (fns);
2581 /* [over.match.funcs] For conversion functions, the function
2582 is considered to be a member of the class of the implicit
2583 object argument for the purpose of defining the type of
2584 the implicit object parameter.
2586 So we pass fromtype as CTYPE to add_*_candidate. */
2588 if (TREE_CODE (fn) == TEMPLATE_DECL)
2589 cand = add_template_candidate (&candidates, fn, fromtype,
2592 TYPE_BINFO (fromtype),
2597 cand = add_function_candidate (&candidates, fn, fromtype,
2599 TYPE_BINFO (fromtype),
2606 = implicit_conversion (totype,
2607 TREE_TYPE (TREE_TYPE (cand->fn)),
2609 /*c_cast_p=*/false, convflags);
2611 cand->second_conv = ics;
2615 else if (candidates->viable == 1 && ics->bad_p)
2621 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2625 cand = tourney (candidates);
2628 if (flags & LOOKUP_COMPLAIN)
2630 error ("conversion from %qT to %qT is ambiguous",
2632 print_z_candidates (candidates);
2635 cand = candidates; /* any one will do */
2636 cand->second_conv = build_ambiguous_conv (totype, expr);
2637 cand->second_conv->user_conv_p = true;
2638 if (!any_strictly_viable (candidates))
2639 cand->second_conv->bad_p = true;
2640 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2641 ambiguous conversion is no worse than another user-defined
2647 /* Build the user conversion sequence. */
2650 (DECL_CONSTRUCTOR_P (cand->fn)
2651 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2652 build_identity_conv (TREE_TYPE (expr), expr));
2655 /* Combine it with the second conversion sequence. */
2656 cand->second_conv = merge_conversion_sequences (conv,
2659 if (cand->viable == -1)
2660 cand->second_conv->bad_p = true;
2666 build_user_type_conversion (tree totype, tree expr, int flags)
2668 struct z_candidate *cand
2669 = build_user_type_conversion_1 (totype, expr, flags);
2673 if (cand->second_conv->kind == ck_ambig)
2674 return error_mark_node;
2675 expr = convert_like (cand->second_conv, expr);
2676 return convert_from_reference (expr);
2681 /* Do any initial processing on the arguments to a function call. */
2684 resolve_args (tree args)
2687 for (t = args; t; t = TREE_CHAIN (t))
2689 tree arg = TREE_VALUE (t);
2691 if (error_operand_p (arg))
2692 return error_mark_node;
2693 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2695 error ("invalid use of void expression");
2696 return error_mark_node;
2702 /* Perform overload resolution on FN, which is called with the ARGS.
2704 Return the candidate function selected by overload resolution, or
2705 NULL if the event that overload resolution failed. In the case
2706 that overload resolution fails, *CANDIDATES will be the set of
2707 candidates considered, and ANY_VIABLE_P will be set to true or
2708 false to indicate whether or not any of the candidates were
2711 The ARGS should already have gone through RESOLVE_ARGS before this
2712 function is called. */
2714 static struct z_candidate *
2715 perform_overload_resolution (tree fn,
2717 struct z_candidate **candidates,
2720 struct z_candidate *cand;
2721 tree explicit_targs = NULL_TREE;
2722 int template_only = 0;
2725 *any_viable_p = true;
2727 /* Check FN and ARGS. */
2728 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
2729 || TREE_CODE (fn) == TEMPLATE_DECL
2730 || TREE_CODE (fn) == OVERLOAD
2731 || TREE_CODE (fn) == TEMPLATE_ID_EXPR);
2732 gcc_assert (!args || TREE_CODE (args) == TREE_LIST);
2734 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2736 explicit_targs = TREE_OPERAND (fn, 1);
2737 fn = TREE_OPERAND (fn, 0);
2741 /* Add the various candidate functions. */
2742 add_candidates (fn, args, explicit_targs, template_only,
2743 /*conversion_path=*/NULL_TREE,
2744 /*access_path=*/NULL_TREE,
2748 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2752 cand = tourney (*candidates);
2756 /* Return an expression for a call to FN (a namespace-scope function,
2757 or a static member function) with the ARGS. */
2760 build_new_function_call (tree fn, tree args, bool koenig_p)
2762 struct z_candidate *candidates, *cand;
2767 args = resolve_args (args);
2768 if (args == error_mark_node)
2769 return error_mark_node;
2771 /* If this function was found without using argument dependent
2772 lookup, then we want to ignore any undeclared friend
2778 fn = remove_hidden_names (fn);
2781 error ("no matching function for call to %<%D(%A)%>",
2782 DECL_NAME (OVL_CURRENT (orig_fn)), args);
2783 return error_mark_node;
2787 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2788 p = conversion_obstack_alloc (0);
2790 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2794 if (!any_viable_p && candidates && ! candidates->next)
2795 return build_function_call (candidates->fn, args);
2796 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2797 fn = TREE_OPERAND (fn, 0);
2799 error ("no matching function for call to %<%D(%A)%>",
2800 DECL_NAME (OVL_CURRENT (fn)), args);
2802 error ("call of overloaded %<%D(%A)%> is ambiguous",
2803 DECL_NAME (OVL_CURRENT (fn)), args);
2805 print_z_candidates (candidates);
2806 result = error_mark_node;
2809 result = build_over_call (cand, LOOKUP_NORMAL);
2811 /* Free all the conversions we allocated. */
2812 obstack_free (&conversion_obstack, p);
2817 /* Build a call to a global operator new. FNNAME is the name of the
2818 operator (either "operator new" or "operator new[]") and ARGS are
2819 the arguments provided. *SIZE points to the total number of bytes
2820 required by the allocation, and is updated if that is changed here.
2821 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2822 function determines that no cookie should be used, after all,
2823 *COOKIE_SIZE is set to NULL_TREE. */
2826 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2829 struct z_candidate *candidates;
2830 struct z_candidate *cand;
2833 args = tree_cons (NULL_TREE, *size, args);
2834 args = resolve_args (args);
2835 if (args == error_mark_node)
2842 If this lookup fails to find the name, or if the allocated type
2843 is not a class type, the allocation function's name is looked
2844 up in the global scope.
2846 we disregard block-scope declarations of "operator new". */
2847 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
2849 /* Figure out what function is being called. */
2850 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2852 /* If no suitable function could be found, issue an error message
2857 error ("no matching function for call to %<%D(%A)%>",
2858 DECL_NAME (OVL_CURRENT (fns)), args);
2860 error ("call of overloaded %<%D(%A)%> is ambiguous",
2861 DECL_NAME (OVL_CURRENT (fns)), args);
2863 print_z_candidates (candidates);
2864 return error_mark_node;
2867 /* If a cookie is required, add some extra space. Whether
2868 or not a cookie is required cannot be determined until
2869 after we know which function was called. */
2872 bool use_cookie = true;
2873 if (!abi_version_at_least (2))
2875 tree placement = TREE_CHAIN (args);
2876 /* In G++ 3.2, the check was implemented incorrectly; it
2877 looked at the placement expression, rather than the
2878 type of the function. */
2879 if (placement && !TREE_CHAIN (placement)
2880 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2888 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2889 /* Skip the size_t parameter. */
2890 arg_types = TREE_CHAIN (arg_types);
2891 /* Check the remaining parameters (if any). */
2893 && TREE_CHAIN (arg_types) == void_list_node
2894 && same_type_p (TREE_VALUE (arg_types),
2898 /* If we need a cookie, adjust the number of bytes allocated. */
2901 /* Update the total size. */
2902 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2903 /* Update the argument list to reflect the adjusted size. */
2904 TREE_VALUE (args) = *size;
2907 *cookie_size = NULL_TREE;
2910 /* Build the CALL_EXPR. */
2911 return build_over_call (cand, LOOKUP_NORMAL);
2915 build_object_call (tree obj, tree args)
2917 struct z_candidate *candidates = 0, *cand;
2918 tree fns, convs, mem_args = NULL_TREE;
2919 tree type = TREE_TYPE (obj);
2921 tree result = NULL_TREE;
2924 if (TYPE_PTRMEMFUNC_P (type))
2926 /* It's no good looking for an overloaded operator() on a
2927 pointer-to-member-function. */
2928 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2929 return error_mark_node;
2932 if (TYPE_BINFO (type))
2934 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2935 if (fns == error_mark_node)
2936 return error_mark_node;
2941 args = resolve_args (args);
2943 if (args == error_mark_node)
2944 return error_mark_node;
2946 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2947 p = conversion_obstack_alloc (0);
2951 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2952 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2954 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2956 tree fn = OVL_CURRENT (fns);
2957 if (TREE_CODE (fn) == TEMPLATE_DECL)
2958 add_template_candidate (&candidates, fn, base, NULL_TREE,
2959 mem_args, NULL_TREE,
2962 LOOKUP_NORMAL, DEDUCE_CALL);
2964 add_function_candidate
2965 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2966 TYPE_BINFO (type), LOOKUP_NORMAL);
2970 convs = lookup_conversions (type);
2972 for (; convs; convs = TREE_CHAIN (convs))
2974 tree fns = TREE_VALUE (convs);
2975 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2977 if ((TREE_CODE (totype) == POINTER_TYPE
2978 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2979 || (TREE_CODE (totype) == REFERENCE_TYPE
2980 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2981 || (TREE_CODE (totype) == REFERENCE_TYPE
2982 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2983 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2984 for (; fns; fns = OVL_NEXT (fns))
2986 tree fn = OVL_CURRENT (fns);
2987 if (TREE_CODE (fn) == TEMPLATE_DECL)
2988 add_template_conv_candidate
2989 (&candidates, fn, obj, args, totype,
2990 /*access_path=*/NULL_TREE,
2991 /*conversion_path=*/NULL_TREE);
2993 add_conv_candidate (&candidates, fn, obj, args,
2994 /*conversion_path=*/NULL_TREE,
2995 /*access_path=*/NULL_TREE);
2999 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3002 error ("no match for call to %<(%T) (%A)%>", TREE_TYPE (obj), args);
3003 print_z_candidates (candidates);
3004 result = error_mark_node;
3008 cand = tourney (candidates);
3011 error ("call of %<(%T) (%A)%> is ambiguous", TREE_TYPE (obj), args);
3012 print_z_candidates (candidates);
3013 result = error_mark_node;
3015 /* Since cand->fn will be a type, not a function, for a conversion
3016 function, we must be careful not to unconditionally look at
3018 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
3019 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
3020 result = build_over_call (cand, LOOKUP_NORMAL);
3023 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1);
3024 obj = convert_from_reference (obj);
3025 result = build_function_call (obj, args);
3029 /* Free all the conversions we allocated. */
3030 obstack_free (&conversion_obstack, p);
3036 op_error (enum tree_code code, enum tree_code code2,
3037 tree arg1, tree arg2, tree arg3, const char *problem)
3041 if (code == MODIFY_EXPR)
3042 opname = assignment_operator_name_info[code2].name;
3044 opname = operator_name_info[code].name;
3049 error ("%s for ternary %<operator?:%> in %<%E ? %E : %E%>",
3050 problem, arg1, arg2, arg3);
3053 case POSTINCREMENT_EXPR:
3054 case POSTDECREMENT_EXPR:
3055 error ("%s for %<operator%s%> in %<%E%s%>", problem, opname, arg1, opname);
3059 error ("%s for %<operator[]%> in %<%E[%E]%>", problem, arg1, arg2);
3064 error ("%s for %qs in %<%s %E%>", problem, opname, opname, arg1);
3069 error ("%s for %<operator%s%> in %<%E %s %E%>",
3070 problem, opname, arg1, opname, arg2);
3072 error ("%s for %<operator%s%> in %<%s%E%>",
3073 problem, opname, opname, arg1);
3078 /* Return the implicit conversion sequence that could be used to
3079 convert E1 to E2 in [expr.cond]. */
3082 conditional_conversion (tree e1, tree e2)
3084 tree t1 = non_reference (TREE_TYPE (e1));
3085 tree t2 = non_reference (TREE_TYPE (e2));
3091 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3092 implicitly converted (clause _conv_) to the type "reference to
3093 T2", subject to the constraint that in the conversion the
3094 reference must bind directly (_dcl.init.ref_) to E1. */
3095 if (real_lvalue_p (e2))
3097 conv = implicit_conversion (build_reference_type (t2),
3101 LOOKUP_NO_TEMP_BIND);
3108 If E1 and E2 have class type, and the underlying class types are
3109 the same or one is a base class of the other: E1 can be converted
3110 to match E2 if the class of T2 is the same type as, or a base
3111 class of, the class of T1, and the cv-qualification of T2 is the
3112 same cv-qualification as, or a greater cv-qualification than, the
3113 cv-qualification of T1. If the conversion is applied, E1 is
3114 changed to an rvalue of type T2 that still refers to the original
3115 source class object (or the appropriate subobject thereof). */
3116 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3117 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3119 if (good_base && at_least_as_qualified_p (t2, t1))
3121 conv = build_identity_conv (t1, e1);
3122 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3123 TYPE_MAIN_VARIANT (t2)))
3124 conv = build_conv (ck_base, t2, conv);
3126 conv = build_conv (ck_rvalue, t2, conv);
3135 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3136 converted to the type that expression E2 would have if E2 were
3137 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3138 return implicit_conversion (t2, t1, e1, /*c_cast_p=*/false,
3142 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3143 arguments to the conditional expression. */
3146 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3150 tree result = NULL_TREE;
3151 tree result_type = NULL_TREE;
3152 bool lvalue_p = true;
3153 struct z_candidate *candidates = 0;
3154 struct z_candidate *cand;
3157 /* As a G++ extension, the second argument to the conditional can be
3158 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3159 c'.) If the second operand is omitted, make sure it is
3160 calculated only once. */
3164 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3166 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3167 if (real_lvalue_p (arg1))
3168 arg2 = arg1 = stabilize_reference (arg1);
3170 arg2 = arg1 = save_expr (arg1);
3175 The first expr ession is implicitly converted to bool (clause
3177 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3179 /* If something has already gone wrong, just pass that fact up the
3181 if (error_operand_p (arg1)
3182 || error_operand_p (arg2)
3183 || error_operand_p (arg3))
3184 return error_mark_node;
3188 If either the second or the third operand has type (possibly
3189 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3190 array-to-pointer (_conv.array_), and function-to-pointer
3191 (_conv.func_) standard conversions are performed on the second
3192 and third operands. */
3193 arg2_type = TREE_TYPE (arg2);
3194 arg3_type = TREE_TYPE (arg3);
3195 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3197 /* Do the conversions. We don't these for `void' type arguments
3198 since it can't have any effect and since decay_conversion
3199 does not handle that case gracefully. */
3200 if (!VOID_TYPE_P (arg2_type))
3201 arg2 = decay_conversion (arg2);
3202 if (!VOID_TYPE_P (arg3_type))
3203 arg3 = decay_conversion (arg3);
3204 arg2_type = TREE_TYPE (arg2);
3205 arg3_type = TREE_TYPE (arg3);
3209 One of the following shall hold:
3211 --The second or the third operand (but not both) is a
3212 throw-expression (_except.throw_); the result is of the
3213 type of the other and is an rvalue.
3215 --Both the second and the third operands have type void; the
3216 result is of type void and is an rvalue.
3218 We must avoid calling force_rvalue for expressions of type
3219 "void" because it will complain that their value is being
3221 if (TREE_CODE (arg2) == THROW_EXPR
3222 && TREE_CODE (arg3) != THROW_EXPR)
3224 if (!VOID_TYPE_P (arg3_type))
3225 arg3 = force_rvalue (arg3);
3226 arg3_type = TREE_TYPE (arg3);
3227 result_type = arg3_type;
3229 else if (TREE_CODE (arg2) != THROW_EXPR
3230 && TREE_CODE (arg3) == THROW_EXPR)
3232 if (!VOID_TYPE_P (arg2_type))
3233 arg2 = force_rvalue (arg2);
3234 arg2_type = TREE_TYPE (arg2);
3235 result_type = arg2_type;
3237 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3238 result_type = void_type_node;
3241 error ("%qE has type %<void%> and is not a throw-expression",
3242 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3243 return error_mark_node;
3247 goto valid_operands;
3251 Otherwise, if the second and third operand have different types,
3252 and either has (possibly cv-qualified) class type, an attempt is
3253 made to convert each of those operands to the type of the other. */
3254 else if (!same_type_p (arg2_type, arg3_type)
3255 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3260 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3261 p = conversion_obstack_alloc (0);
3263 conv2 = conditional_conversion (arg2, arg3);
3264 conv3 = conditional_conversion (arg3, arg2);
3268 If both can be converted, or one can be converted but the
3269 conversion is ambiguous, the program is ill-formed. If
3270 neither can be converted, the operands are left unchanged and
3271 further checking is performed as described below. If exactly
3272 one conversion is possible, that conversion is applied to the
3273 chosen operand and the converted operand is used in place of
3274 the original operand for the remainder of this section. */
3275 if ((conv2 && !conv2->bad_p
3276 && conv3 && !conv3->bad_p)
3277 || (conv2 && conv2->kind == ck_ambig)
3278 || (conv3 && conv3->kind == ck_ambig))
3280 error ("operands to ?: have different types %qT and %qT",
3281 arg2_type, arg3_type);
3282 result = error_mark_node;
3284 else if (conv2 && (!conv2->bad_p || !conv3))
3286 arg2 = convert_like (conv2, arg2);
3287 arg2 = convert_from_reference (arg2);
3288 arg2_type = TREE_TYPE (arg2);
3290 else if (conv3 && (!conv3->bad_p || !conv2))
3292 arg3 = convert_like (conv3, arg3);
3293 arg3 = convert_from_reference (arg3);
3294 arg3_type = TREE_TYPE (arg3);
3297 /* Free all the conversions we allocated. */
3298 obstack_free (&conversion_obstack, p);
3303 /* If, after the conversion, both operands have class type,
3304 treat the cv-qualification of both operands as if it were the
3305 union of the cv-qualification of the operands.
3307 The standard is not clear about what to do in this
3308 circumstance. For example, if the first operand has type
3309 "const X" and the second operand has a user-defined
3310 conversion to "volatile X", what is the type of the second
3311 operand after this step? Making it be "const X" (matching
3312 the first operand) seems wrong, as that discards the
3313 qualification without actually performing a copy. Leaving it
3314 as "volatile X" seems wrong as that will result in the
3315 conditional expression failing altogether, even though,
3316 according to this step, the one operand could be converted to
3317 the type of the other. */
3318 if ((conv2 || conv3)
3319 && CLASS_TYPE_P (arg2_type)
3320 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3321 arg2_type = arg3_type =
3322 cp_build_qualified_type (arg2_type,
3323 TYPE_QUALS (arg2_type)
3324 | TYPE_QUALS (arg3_type));
3329 If the second and third operands are lvalues and have the same
3330 type, the result is of that type and is an lvalue. */
3331 if (real_lvalue_p (arg2)
3332 && real_lvalue_p (arg3)
3333 && same_type_p (arg2_type, arg3_type))
3335 result_type = arg2_type;
3336 goto valid_operands;
3341 Otherwise, the result is an rvalue. If the second and third
3342 operand do not have the same type, and either has (possibly
3343 cv-qualified) class type, overload resolution is used to
3344 determine the conversions (if any) to be applied to the operands
3345 (_over.match.oper_, _over.built_). */
3347 if (!same_type_p (arg2_type, arg3_type)
3348 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3354 /* Rearrange the arguments so that add_builtin_candidate only has
3355 to know about two args. In build_builtin_candidates, the
3356 arguments are unscrambled. */
3360 add_builtin_candidates (&candidates,
3363 ansi_opname (COND_EXPR),
3369 If the overload resolution fails, the program is
3371 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3374 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3375 print_z_candidates (candidates);
3376 return error_mark_node;
3378 cand = tourney (candidates);
3381 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3382 print_z_candidates (candidates);
3383 return error_mark_node;
3388 Otherwise, the conversions thus determined are applied, and
3389 the converted operands are used in place of the original
3390 operands for the remainder of this section. */
3391 conv = cand->convs[0];
3392 arg1 = convert_like (conv, arg1);
3393 conv = cand->convs[1];
3394 arg2 = convert_like (conv, arg2);
3395 conv = cand->convs[2];
3396 arg3 = convert_like (conv, arg3);
3401 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3402 and function-to-pointer (_conv.func_) standard conversions are
3403 performed on the second and third operands.
3405 We need to force the lvalue-to-rvalue conversion here for class types,
3406 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3407 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3410 arg2 = force_rvalue (arg2);
3411 if (!CLASS_TYPE_P (arg2_type))
3412 arg2_type = TREE_TYPE (arg2);
3414 arg3 = force_rvalue (arg3);
3415 if (!CLASS_TYPE_P (arg2_type))
3416 arg3_type = TREE_TYPE (arg3);
3418 if (arg2 == error_mark_node || arg3 == error_mark_node)
3419 return error_mark_node;
3423 After those conversions, one of the following shall hold:
3425 --The second and third operands have the same type; the result is of
3427 if (same_type_p (arg2_type, arg3_type))
3428 result_type = arg2_type;
3431 --The second and third operands have arithmetic or enumeration
3432 type; the usual arithmetic conversions are performed to bring
3433 them to a common type, and the result is of that type. */
3434 else if ((ARITHMETIC_TYPE_P (arg2_type)
3435 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3436 && (ARITHMETIC_TYPE_P (arg3_type)
3437 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3439 /* In this case, there is always a common type. */
3440 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3443 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3444 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3445 warning (0, "enumeral mismatch in conditional expression: %qT vs %qT",
3446 arg2_type, arg3_type);
3447 else if (extra_warnings
3448 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3449 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3450 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3451 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3452 warning (0, "enumeral and non-enumeral type in conditional expression");
3454 arg2 = perform_implicit_conversion (result_type, arg2);
3455 arg3 = perform_implicit_conversion (result_type, arg3);
3459 --The second and third operands have pointer type, or one has
3460 pointer type and the other is a null pointer constant; pointer
3461 conversions (_conv.ptr_) and qualification conversions
3462 (_conv.qual_) are performed to bring them to their composite
3463 pointer type (_expr.rel_). The result is of the composite
3466 --The second and third operands have pointer to member type, or
3467 one has pointer to member type and the other is a null pointer
3468 constant; pointer to member conversions (_conv.mem_) and
3469 qualification conversions (_conv.qual_) are performed to bring
3470 them to a common type, whose cv-qualification shall match the
3471 cv-qualification of either the second or the third operand.
3472 The result is of the common type. */
3473 else if ((null_ptr_cst_p (arg2)
3474 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3475 || (null_ptr_cst_p (arg3)
3476 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3477 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3478 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3479 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3481 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3482 arg3, "conditional expression");
3483 if (result_type == error_mark_node)
3484 return error_mark_node;
3485 arg2 = perform_implicit_conversion (result_type, arg2);
3486 arg3 = perform_implicit_conversion (result_type, arg3);
3491 error ("operands to ?: have different types %qT and %qT",
3492 arg2_type, arg3_type);
3493 return error_mark_node;
3497 result = fold_if_not_in_template (build3 (COND_EXPR, result_type, arg1,
3499 /* We can't use result_type below, as fold might have returned a
3502 /* Expand both sides into the same slot, hopefully the target of the
3503 ?: expression. We used to check for TARGET_EXPRs here, but now we
3504 sometimes wrap them in NOP_EXPRs so the test would fail. */
3505 if (!lvalue_p && CLASS_TYPE_P (TREE_TYPE (result)))
3506 result = get_target_expr (result);
3508 /* If this expression is an rvalue, but might be mistaken for an
3509 lvalue, we must add a NON_LVALUE_EXPR. */
3510 if (!lvalue_p && real_lvalue_p (result))
3511 result = rvalue (result);
3516 /* OPERAND is an operand to an expression. Perform necessary steps
3517 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3521 prep_operand (tree operand)
3525 if (CLASS_TYPE_P (TREE_TYPE (operand))
3526 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3527 /* Make sure the template type is instantiated now. */
3528 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3534 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3535 OVERLOAD) to the CANDIDATES, returning an updated list of
3536 CANDIDATES. The ARGS are the arguments provided to the call,
3537 without any implicit object parameter. The EXPLICIT_TARGS are
3538 explicit template arguments provided. TEMPLATE_ONLY is true if
3539 only template functions should be considered. CONVERSION_PATH,
3540 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3543 add_candidates (tree fns, tree args,
3544 tree explicit_targs, bool template_only,
3545 tree conversion_path, tree access_path,
3547 struct z_candidate **candidates)
3550 tree non_static_args;
3552 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3553 /* Delay creating the implicit this parameter until it is needed. */
3554 non_static_args = NULL_TREE;
3561 fn = OVL_CURRENT (fns);
3562 /* Figure out which set of arguments to use. */
3563 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3565 /* If this function is a non-static member, prepend the implicit
3566 object parameter. */
3567 if (!non_static_args)
3568 non_static_args = tree_cons (NULL_TREE,
3569 build_this (TREE_VALUE (args)),
3571 fn_args = non_static_args;
3574 /* Otherwise, just use the list of arguments provided. */
3577 if (TREE_CODE (fn) == TEMPLATE_DECL)
3578 add_template_candidate (candidates,
3588 else if (!template_only)
3589 add_function_candidate (candidates,
3596 fns = OVL_NEXT (fns);
3601 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3604 struct z_candidate *candidates = 0, *cand;
3605 tree arglist, fnname;
3607 tree result = NULL_TREE;
3608 bool result_valid_p = false;
3609 enum tree_code code2 = NOP_EXPR;
3615 if (error_operand_p (arg1)
3616 || error_operand_p (arg2)
3617 || error_operand_p (arg3))
3618 return error_mark_node;
3620 if (code == MODIFY_EXPR)
3622 code2 = TREE_CODE (arg3);
3624 fnname = ansi_assopname (code2);
3627 fnname = ansi_opname (code);
3629 arg1 = prep_operand (arg1);
3635 case VEC_DELETE_EXPR:
3637 /* Use build_op_new_call and build_op_delete_call instead. */
3641 return build_object_call (arg1, arg2);
3647 arg2 = prep_operand (arg2);
3648 arg3 = prep_operand (arg3);
3650 if (code == COND_EXPR)
3652 if (arg2 == NULL_TREE
3653 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3654 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3655 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3656 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3659 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3660 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3663 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3664 arg2 = integer_zero_node;
3666 arglist = NULL_TREE;
3668 arglist = tree_cons (NULL_TREE, arg3, arglist);
3670 arglist = tree_cons (NULL_TREE, arg2, arglist);
3671 arglist = tree_cons (NULL_TREE, arg1, arglist);
3673 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3674 p = conversion_obstack_alloc (0);
3676 /* Add namespace-scope operators to the list of functions to
3678 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3679 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3680 flags, &candidates);
3681 /* Add class-member operators to the candidate set. */
3682 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3686 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3687 if (fns == error_mark_node)
3689 result = error_mark_node;
3690 goto user_defined_result_ready;
3693 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3695 BASELINK_BINFO (fns),
3696 TYPE_BINFO (TREE_TYPE (arg1)),
3697 flags, &candidates);
3700 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3701 to know about two args; a builtin candidate will always have a first
3702 parameter of type bool. We'll handle that in
3703 build_builtin_candidate. */
3704 if (code == COND_EXPR)
3714 args[2] = NULL_TREE;
3717 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3723 /* For these, the built-in candidates set is empty
3724 [over.match.oper]/3. We don't want non-strict matches
3725 because exact matches are always possible with built-in
3726 operators. The built-in candidate set for COMPONENT_REF
3727 would be empty too, but since there are no such built-in
3728 operators, we accept non-strict matches for them. */
3733 strict_p = pedantic;
3737 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3742 case POSTINCREMENT_EXPR:
3743 case POSTDECREMENT_EXPR:
3744 /* Look for an `operator++ (int)'. If they didn't have
3745 one, then we fall back to the old way of doing things. */
3746 if (flags & LOOKUP_COMPLAIN)
3747 pedwarn ("no %<%D(int)%> declared for postfix %qs, "
3748 "trying prefix operator instead",
3750 operator_name_info[code].name);
3751 if (code == POSTINCREMENT_EXPR)
3752 code = PREINCREMENT_EXPR;
3754 code = PREDECREMENT_EXPR;
3755 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
3759 /* The caller will deal with these. */
3764 result_valid_p = true;
3768 if (flags & LOOKUP_COMPLAIN)
3770 op_error (code, code2, arg1, arg2, arg3, "no match");
3771 print_z_candidates (candidates);
3773 result = error_mark_node;
3779 cand = tourney (candidates);
3782 if (flags & LOOKUP_COMPLAIN)
3784 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3785 print_z_candidates (candidates);
3787 result = error_mark_node;
3789 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3792 *overloaded_p = true;
3794 result = build_over_call (cand, LOOKUP_NORMAL);
3798 /* Give any warnings we noticed during overload resolution. */
3801 struct candidate_warning *w;
3802 for (w = cand->warnings; w; w = w->next)
3803 joust (cand, w->loser, 1);
3806 /* Check for comparison of different enum types. */
3815 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3816 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3817 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3818 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3820 warning (0, "comparison between %q#T and %q#T",
3821 TREE_TYPE (arg1), TREE_TYPE (arg2));
3828 /* We need to strip any leading REF_BIND so that bitfields
3829 don't cause errors. This should not remove any important
3830 conversions, because builtins don't apply to class
3831 objects directly. */
3832 conv = cand->convs[0];
3833 if (conv->kind == ck_ref_bind)
3834 conv = conv->u.next;
3835 arg1 = convert_like (conv, arg1);
3838 conv = cand->convs[1];
3839 if (conv->kind == ck_ref_bind)
3840 conv = conv->u.next;
3841 arg2 = convert_like (conv, arg2);
3845 conv = cand->convs[2];
3846 if (conv->kind == ck_ref_bind)
3847 conv = conv->u.next;
3848 arg3 = convert_like (conv, arg3);
3853 user_defined_result_ready:
3855 /* Free all the conversions we allocated. */
3856 obstack_free (&conversion_obstack, p);
3858 if (result || result_valid_p)
3865 return build_modify_expr (arg1, code2, arg2);
3868 return build_indirect_ref (arg1, "unary *");
3873 case TRUNC_DIV_EXPR:
3884 case TRUNC_MOD_EXPR:
3888 case TRUTH_ANDIF_EXPR:
3889 case TRUTH_ORIF_EXPR:
3890 return cp_build_binary_op (code, arg1, arg2);
3892 case UNARY_PLUS_EXPR:
3895 case TRUTH_NOT_EXPR:
3896 case PREINCREMENT_EXPR:
3897 case POSTINCREMENT_EXPR:
3898 case PREDECREMENT_EXPR:
3899 case POSTDECREMENT_EXPR:
3902 return build_unary_op (code, arg1, candidates != 0);
3905 return build_array_ref (arg1, arg2);
3908 return build_conditional_expr (arg1, arg2, arg3);
3911 return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2);
3913 /* The caller will deal with these. */
3925 /* Build a call to operator delete. This has to be handled very specially,
3926 because the restrictions on what signatures match are different from all
3927 other call instances. For a normal delete, only a delete taking (void *)
3928 or (void *, size_t) is accepted. For a placement delete, only an exact
3929 match with the placement new is accepted.
3931 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3932 ADDR is the pointer to be deleted.
3933 SIZE is the size of the memory block to be deleted.
3934 GLOBAL_P is true if the delete-expression should not consider
3935 class-specific delete operators.
3936 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3939 build_op_delete_call (enum tree_code code, tree addr, tree size,
3940 bool global_p, tree placement)
3942 tree fn = NULL_TREE;
3943 tree fns, fnname, argtypes, args, type;
3946 if (addr == error_mark_node)
3947 return error_mark_node;
3949 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3951 fnname = ansi_opname (code);
3953 if (CLASS_TYPE_P (type)
3954 && COMPLETE_TYPE_P (complete_type (type))
3958 If the result of the lookup is ambiguous or inaccessible, or if
3959 the lookup selects a placement deallocation function, the
3960 program is ill-formed.
3962 Therefore, we ask lookup_fnfields to complain about ambiguity. */
3964 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3965 if (fns == error_mark_node)
3966 return error_mark_node;
3971 if (fns == NULL_TREE)
3972 fns = lookup_name_nonclass (fnname);
3979 /* Find the allocation function that is being called. */
3980 call_expr = placement;
3981 /* Extract the function. */
3982 alloc_fn = get_callee_fndecl (call_expr);
3983 gcc_assert (alloc_fn != NULL_TREE);
3984 /* Then the second parm type. */
3985 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3986 /* Also the second argument. */
3987 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3991 /* First try it without the size argument. */
3992 argtypes = void_list_node;
3996 /* Strip const and volatile from addr. */
3997 addr = cp_convert (ptr_type_node, addr);
3999 /* We make two tries at finding a matching `operator delete'. On
4000 the first pass, we look for a one-operator (or placement)
4001 operator delete. If we're not doing placement delete, then on
4002 the second pass we look for a two-argument delete. */
4003 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
4005 /* Go through the `operator delete' functions looking for one
4006 with a matching type. */
4007 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
4013 /* The first argument must be "void *". */
4014 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
4015 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
4018 /* On the first pass, check the rest of the arguments. */
4024 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4032 /* On the second pass, the second argument must be
4035 && same_type_p (TREE_VALUE (t), sizetype)
4036 && TREE_CHAIN (t) == void_list_node)
4040 /* If we found a match, we're done. */
4045 /* If we have a matching function, call it. */
4048 /* Make sure we have the actual function, and not an
4050 fn = OVL_CURRENT (fn);
4052 /* If the FN is a member function, make sure that it is
4054 if (DECL_CLASS_SCOPE_P (fn))
4055 perform_or_defer_access_check (TYPE_BINFO (type), fn);
4058 args = tree_cons (NULL_TREE, addr, args);
4060 args = tree_cons (NULL_TREE, addr,
4061 build_tree_list (NULL_TREE, size));
4065 /* The placement args might not be suitable for overload
4066 resolution at this point, so build the call directly. */
4068 return build_cxx_call (fn, args);
4071 return build_function_call (fn, args);
4074 /* If we are doing placement delete we do nothing if we don't find a
4075 matching op delete. */
4079 error ("no suitable %<operator %s%> for %qT",
4080 operator_name_info[(int)code].name, type);
4081 return error_mark_node;
4084 /* If the current scope isn't allowed to access DECL along
4085 BASETYPE_PATH, give an error. The most derived class in
4086 BASETYPE_PATH is the one used to qualify DECL. */
4089 enforce_access (tree basetype_path, tree decl)
4091 gcc_assert (TREE_CODE (basetype_path) == TREE_BINFO);
4093 if (!accessible_p (basetype_path, decl, true))
4095 if (TREE_PRIVATE (decl))
4096 error ("%q+#D is private", decl);
4097 else if (TREE_PROTECTED (decl))
4098 error ("%q+#D is protected", decl);
4100 error ("%q+#D is inaccessible", decl);
4101 error ("within this context");
4108 /* Check that a callable constructor to initialize a temporary of
4109 TYPE from an EXPR exists. */
4112 check_constructor_callable (tree type, tree expr)
4114 build_special_member_call (NULL_TREE,
4115 complete_ctor_identifier,
4116 build_tree_list (NULL_TREE, expr),
4118 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING
4119 | LOOKUP_NO_CONVERSION
4120 | LOOKUP_CONSTRUCTOR_CALLABLE);
4123 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4124 bitwise or of LOOKUP_* values. If any errors are warnings are
4125 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4126 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4130 build_temp (tree expr, tree type, int flags,
4131 diagnostic_fn_t *diagnostic_fn)
4135 savew = warningcount, savee = errorcount;
4136 expr = build_special_member_call (NULL_TREE,
4137 complete_ctor_identifier,
4138 build_tree_list (NULL_TREE, expr),
4140 if (warningcount > savew)
4141 *diagnostic_fn = warning0;
4142 else if (errorcount > savee)
4143 *diagnostic_fn = error;
4145 *diagnostic_fn = NULL;
4150 /* Perform the conversions in CONVS on the expression EXPR. FN and
4151 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4152 indicates the `this' argument of a method. INNER is nonzero when
4153 being called to continue a conversion chain. It is negative when a
4154 reference binding will be applied, positive otherwise. If
4155 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4156 conversions will be emitted if appropriate. If C_CAST_P is true,
4157 this conversion is coming from a C-style cast; in that case,
4158 conversions to inaccessible bases are permitted. */
4161 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4162 int inner, bool issue_conversion_warnings,
4165 tree totype = convs->type;
4166 diagnostic_fn_t diagnostic_fn;
4169 && convs->kind != ck_user
4170 && convs->kind != ck_ambig
4171 && convs->kind != ck_ref_bind)
4173 conversion *t = convs;
4174 for (; t; t = convs->u.next)
4176 if (t->kind == ck_user || !t->bad_p)
4178 expr = convert_like_real (t, expr, fn, argnum, 1,
4179 /*issue_conversion_warnings=*/false,
4180 /*c_cast_p=*/false);
4183 else if (t->kind == ck_ambig)
4184 return convert_like_real (t, expr, fn, argnum, 1,
4185 /*issue_conversion_warnings=*/false,
4186 /*c_cast_p=*/false);
4187 else if (t->kind == ck_identity)
4190 pedwarn ("invalid conversion from %qT to %qT", TREE_TYPE (expr), totype);
4192 pedwarn (" initializing argument %P of %qD", argnum, fn);
4193 return cp_convert (totype, expr);
4196 if (issue_conversion_warnings)
4198 tree t = non_reference (totype);
4200 /* Issue warnings about peculiar, but valid, uses of NULL. */
4201 if (ARITHMETIC_TYPE_P (t) && expr == null_node)
4204 warning (0, "passing NULL to non-pointer argument %P of %qD",
4207 warning (0, "converting to non-pointer type %qT from NULL", t);
4210 /* Warn about assigning a floating-point type to an integer type. */
4211 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
4212 && TREE_CODE (t) == INTEGER_TYPE)
4215 warning (0, "passing %qT for argument %P to %qD",
4216 TREE_TYPE (expr), argnum, fn);
4218 warning (0, "converting to %qT from %qT", t, TREE_TYPE (expr));
4222 switch (convs->kind)
4226 struct z_candidate *cand = convs->cand;
4227 tree convfn = cand->fn;
4230 if (DECL_CONSTRUCTOR_P (convfn))
4232 tree t = build_int_cst (build_pointer_type (DECL_CONTEXT (convfn)),
4235 args = build_tree_list (NULL_TREE, expr);
4236 /* We should never try to call the abstract or base constructor
4238 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (convfn)
4239 && !DECL_HAS_VTT_PARM_P (convfn));
4240 args = tree_cons (NULL_TREE, t, args);
4243 args = build_this (expr);
4244 expr = build_over_call (cand, LOOKUP_NORMAL);
4246 /* If this is a constructor or a function returning an aggr type,
4247 we need to build up a TARGET_EXPR. */
4248 if (DECL_CONSTRUCTOR_P (convfn))
4249 expr = build_cplus_new (totype, expr);
4251 /* The result of the call is then used to direct-initialize the object
4252 that is the destination of the copy-initialization. [dcl.init]
4254 Note that this step is not reflected in the conversion sequence;
4255 it affects the semantics when we actually perform the
4256 conversion, but is not considered during overload resolution.
4258 If the target is a class, that means call a ctor. */
4259 if (IS_AGGR_TYPE (totype)
4260 && (inner >= 0 || !lvalue_p (expr)))
4264 /* Core issue 84, now a DR, says that we don't
4265 allow UDCs for these args (which deliberately
4266 breaks copy-init of an auto_ptr<Base> from an
4267 auto_ptr<Derived>). */
4268 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION,
4275 (" initializing argument %P of %qD from result of %qD",
4276 argnum, fn, convfn);
4279 (" initializing temporary from result of %qD", convfn);
4281 expr = build_cplus_new (totype, expr);
4286 if (type_unknown_p (expr))
4287 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4288 /* Convert a constant to its underlying value, unless we are
4289 about to bind it to a reference, in which case we need to
4290 leave it as an lvalue. */
4292 expr = decl_constant_value (expr);
4293 if (convs->check_copy_constructor_p)
4294 check_constructor_callable (totype, expr);
4297 /* Call build_user_type_conversion again for the error. */
4298 return build_user_type_conversion
4299 (totype, convs->u.expr, LOOKUP_NORMAL);
4305 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4306 convs->kind == ck_ref_bind ? -1 : 1,
4307 /*issue_conversion_warnings=*/false,
4309 if (expr == error_mark_node)
4310 return error_mark_node;
4312 switch (convs->kind)
4315 if (! IS_AGGR_TYPE (totype))
4317 /* Else fall through. */
4319 if (convs->kind == ck_base && !convs->need_temporary_p)
4321 /* We are going to bind a reference directly to a base-class
4322 subobject of EXPR. */
4323 if (convs->check_copy_constructor_p)
4324 check_constructor_callable (TREE_TYPE (expr), expr);
4325 /* Build an expression for `*((base*) &expr)'. */
4326 expr = build_unary_op (ADDR_EXPR, expr, 0);
4327 expr = convert_to_base (expr, build_pointer_type (totype),
4328 !c_cast_p, /*nonnull=*/true);
4329 expr = build_indirect_ref (expr, "implicit conversion");
4333 /* Copy-initialization where the cv-unqualified version of the source
4334 type is the same class as, or a derived class of, the class of the
4335 destination [is treated as direct-initialization]. [dcl.init] */
4336 expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
4338 if (diagnostic_fn && fn)
4339 diagnostic_fn (" initializing argument %P of %qD", argnum, fn);
4340 return build_cplus_new (totype, expr);
4344 tree ref_type = totype;
4346 /* If necessary, create a temporary. */
4347 if (convs->need_temporary_p || !lvalue_p (expr))
4349 tree type = convs->u.next->type;
4350 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4352 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
4354 /* If the reference is volatile or non-const, we
4355 cannot create a temporary. */
4356 if (lvalue & clk_bitfield)
4357 error ("cannot bind bitfield %qE to %qT",
4359 else if (lvalue & clk_packed)
4360 error ("cannot bind packed field %qE to %qT",
4363 error ("cannot bind rvalue %qE to %qT", expr, ref_type);
4364 return error_mark_node;
4366 /* If the source is a packed field, and we must use a copy
4367 constructor, then building the target expr will require
4368 binding the field to the reference parameter to the
4369 copy constructor, and we'll end up with an infinite
4370 loop. If we can use a bitwise copy, then we'll be
4372 if ((lvalue & clk_packed)
4373 && CLASS_TYPE_P (type)
4374 && !TYPE_HAS_TRIVIAL_INIT_REF (type))
4376 error ("cannot bind packed field %qE to %qT",
4378 return error_mark_node;
4380 expr = build_target_expr_with_type (expr, type);
4383 /* Take the address of the thing to which we will bind the
4385 expr = build_unary_op (ADDR_EXPR, expr, 1);
4386 if (expr == error_mark_node)
4387 return error_mark_node;
4389 /* Convert it to a pointer to the type referred to by the
4390 reference. This will adjust the pointer if a derived to
4391 base conversion is being performed. */
4392 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4394 /* Convert the pointer to the desired reference type. */
4395 return build_nop (ref_type, expr);
4399 return decay_conversion (expr);
4402 /* Warn about deprecated conversion if appropriate. */
4403 string_conv_p (totype, expr, 1);
4408 expr = convert_to_base (expr, totype, !c_cast_p,
4410 return build_nop (totype, expr);
4413 return convert_ptrmem (totype, expr, /*allow_inverse_p=*/false,
4420 if (issue_conversion_warnings)
4421 expr = convert_and_check (totype, expr);
4423 expr = convert (totype, expr);
4428 /* Build a call to __builtin_trap. */
4431 call_builtin_trap (void)
4433 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4435 gcc_assert (fn != NULL);
4436 fn = build_call (fn, NULL_TREE);
4440 /* ARG is being passed to a varargs function. Perform any conversions
4441 required. Return the converted value. */
4444 convert_arg_to_ellipsis (tree arg)
4448 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4449 standard conversions are performed. */
4450 arg = decay_conversion (arg);
4453 If the argument has integral or enumeration type that is subject
4454 to the integral promotions (_conv.prom_), or a floating point
4455 type that is subject to the floating point promotion
4456 (_conv.fpprom_), the value of the argument is converted to the
4457 promoted type before the call. */
4458 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4459 && (TYPE_PRECISION (TREE_TYPE (arg))
4460 < TYPE_PRECISION (double_type_node)))
4461 arg = convert_to_real (double_type_node, arg);
4462 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4463 arg = perform_integral_promotions (arg);
4465 arg = require_complete_type (arg);
4467 if (arg != error_mark_node
4468 && !pod_type_p (TREE_TYPE (arg)))
4470 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4471 here and do a bitwise copy, but now cp_expr_size will abort if we
4473 If the call appears in the context of a sizeof expression,
4474 there is no need to emit a warning, since the expression won't be
4475 evaluated. We keep the builtin_trap just as a safety check. */
4476 if (!skip_evaluation)
4477 warning (0, "cannot pass objects of non-POD type %q#T through %<...%>; "
4478 "call will abort at runtime", TREE_TYPE (arg));
4479 arg = call_builtin_trap ();
4480 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4487 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4490 build_x_va_arg (tree expr, tree type)
4492 if (processing_template_decl)
4493 return build_min (VA_ARG_EXPR, type, expr);
4495 type = complete_type_or_else (type, NULL_TREE);
4497 if (expr == error_mark_node || !type)
4498 return error_mark_node;
4500 if (! pod_type_p (type))
4502 /* Undefined behavior [expr.call] 5.2.2/7. */
4503 warning (0, "cannot receive objects of non-POD type %q#T through %<...%>; "
4504 "call will abort at runtime", type);
4505 expr = convert (build_pointer_type (type), null_node);
4506 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4507 call_builtin_trap (), expr);
4508 expr = build_indirect_ref (expr, NULL);
4512 return build_va_arg (expr, type);
4515 /* TYPE has been given to va_arg. Apply the default conversions which
4516 would have happened when passed via ellipsis. Return the promoted
4517 type, or the passed type if there is no change. */
4520 cxx_type_promotes_to (tree type)
4524 /* Perform the array-to-pointer and function-to-pointer
4526 type = type_decays_to (type);
4528 promote = type_promotes_to (type);
4529 if (same_type_p (type, promote))
4535 /* ARG is a default argument expression being passed to a parameter of
4536 the indicated TYPE, which is a parameter to FN. Do any required
4537 conversions. Return the converted value. */
4540 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4542 /* If the ARG is an unparsed default argument expression, the
4543 conversion cannot be performed. */
4544 if (TREE_CODE (arg) == DEFAULT_ARG)
4546 error ("the default argument for parameter %d of %qD has "
4547 "not yet been parsed",
4549 return error_mark_node;
4552 if (fn && DECL_TEMPLATE_INFO (fn))
4553 arg = tsubst_default_argument (fn, type, arg);
4555 arg = break_out_target_exprs (arg);
4557 if (TREE_CODE (arg) == CONSTRUCTOR)
4559 arg = digest_init (type, arg);
4560 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4561 "default argument", fn, parmnum);
4565 /* This could get clobbered by the following call. */
4566 if (TREE_HAS_CONSTRUCTOR (arg))
4567 arg = copy_node (arg);
4569 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4570 "default argument", fn, parmnum);
4571 arg = convert_for_arg_passing (type, arg);
4577 /* Returns the type which will really be used for passing an argument of
4581 type_passed_as (tree type)
4583 /* Pass classes with copy ctors by invisible reference. */
4584 if (TREE_ADDRESSABLE (type))
4586 type = build_reference_type (type);
4587 /* There are no other pointers to this temporary. */
4588 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4590 else if (targetm.calls.promote_prototypes (type)
4591 && INTEGRAL_TYPE_P (type)
4592 && COMPLETE_TYPE_P (type)
4593 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4594 TYPE_SIZE (integer_type_node)))
4595 type = integer_type_node;
4600 /* Actually perform the appropriate conversion. */
4603 convert_for_arg_passing (tree type, tree val)
4605 if (val == error_mark_node)
4607 /* Pass classes with copy ctors by invisible reference. */
4608 else if (TREE_ADDRESSABLE (type))
4609 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4610 else if (targetm.calls.promote_prototypes (type)
4611 && INTEGRAL_TYPE_P (type)
4612 && COMPLETE_TYPE_P (type)
4613 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4614 TYPE_SIZE (integer_type_node)))
4615 val = perform_integral_promotions (val);
4616 if (warn_missing_format_attribute)
4618 tree rhstype = TREE_TYPE (val);
4619 const enum tree_code coder = TREE_CODE (rhstype);
4620 const enum tree_code codel = TREE_CODE (type);
4621 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4623 && check_missing_format_attribute (type, rhstype))
4624 warning (OPT_Wmissing_format_attribute,
4625 "argument of function call might be a candidate for a format attribute");
4630 /* Returns true iff FN is a function with magic varargs, i.e. ones for
4631 which no conversions at all should be done. This is true for some
4632 builtins which don't act like normal functions. */
4635 magic_varargs_p (tree fn)
4637 if (DECL_BUILT_IN (fn))
4638 switch (DECL_FUNCTION_CODE (fn))
4640 case BUILT_IN_CLASSIFY_TYPE:
4641 case BUILT_IN_CONSTANT_P:
4642 case BUILT_IN_NEXT_ARG:
4643 case BUILT_IN_STDARG_START:
4644 case BUILT_IN_VA_START:
4653 /* Subroutine of the various build_*_call functions. Overload resolution
4654 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4655 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4656 bitmask of various LOOKUP_* flags which apply to the call itself. */
4659 build_over_call (struct z_candidate *cand, int flags)
4662 tree args = cand->args;
4663 conversion **convs = cand->convs;
4665 tree converted_args = NULL_TREE;
4666 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4671 /* In a template, there is no need to perform all of the work that
4672 is normally done. We are only interested in the type of the call
4673 expression, i.e., the return type of the function. Any semantic
4674 errors will be deferred until the template is instantiated. */
4675 if (processing_template_decl)
4679 return_type = TREE_TYPE (TREE_TYPE (fn));
4680 expr = build3 (CALL_EXPR, return_type, fn, args, NULL_TREE);
4681 if (TREE_THIS_VOLATILE (fn) && cfun)
4682 current_function_returns_abnormally = 1;
4683 if (!VOID_TYPE_P (return_type))
4684 require_complete_type (return_type);
4685 return convert_from_reference (expr);
4688 /* Give any warnings we noticed during overload resolution. */
4691 struct candidate_warning *w;
4692 for (w = cand->warnings; w; w = w->next)
4693 joust (cand, w->loser, 1);
4696 if (DECL_FUNCTION_MEMBER_P (fn))
4698 /* If FN is a template function, two cases must be considered.
4703 template <class T> void f();
4705 template <class T> struct B {
4709 struct C : A, B<int> {
4711 using B<int>::g; // #2
4714 In case #1 where `A::f' is a member template, DECL_ACCESS is
4715 recorded in the primary template but not in its specialization.
4716 We check access of FN using its primary template.
4718 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
4719 because it is a member of class template B, DECL_ACCESS is
4720 recorded in the specialization `B<int>::g'. We cannot use its
4721 primary template because `B<T>::g' and `B<int>::g' may have
4722 different access. */
4723 if (DECL_TEMPLATE_INFO (fn)
4724 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
4725 perform_or_defer_access_check (cand->access_path,
4726 DECL_TI_TEMPLATE (fn));
4728 perform_or_defer_access_check (cand->access_path, fn);
4731 if (args && TREE_CODE (args) != TREE_LIST)
4732 args = build_tree_list (NULL_TREE, args);
4735 /* The implicit parameters to a constructor are not considered by overload
4736 resolution, and must be of the proper type. */
4737 if (DECL_CONSTRUCTOR_P (fn))
4739 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4740 arg = TREE_CHAIN (arg);
4741 parm = TREE_CHAIN (parm);
4742 /* We should never try to call the abstract constructor. */
4743 gcc_assert (!DECL_HAS_IN_CHARGE_PARM_P (fn));
4745 if (DECL_HAS_VTT_PARM_P (fn))
4747 converted_args = tree_cons
4748 (NULL_TREE, TREE_VALUE (arg), converted_args);
4749 arg = TREE_CHAIN (arg);
4750 parm = TREE_CHAIN (parm);
4753 /* Bypass access control for 'this' parameter. */
4754 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4756 tree parmtype = TREE_VALUE (parm);
4757 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4761 if (convs[i]->bad_p)
4762 pedwarn ("passing %qT as %<this%> argument of %q#D discards qualifiers",
4763 TREE_TYPE (argtype), fn);
4765 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4766 X is called for an object that is not of type X, or of a type
4767 derived from X, the behavior is undefined.
4769 So we can assume that anything passed as 'this' is non-null, and
4770 optimize accordingly. */
4771 gcc_assert (TREE_CODE (parmtype) == POINTER_TYPE);
4772 /* Convert to the base in which the function was declared. */
4773 gcc_assert (cand->conversion_path != NULL_TREE);
4774 converted_arg = build_base_path (PLUS_EXPR,
4776 cand->conversion_path,
4778 /* Check that the base class is accessible. */
4779 if (!accessible_base_p (TREE_TYPE (argtype),
4780 BINFO_TYPE (cand->conversion_path), true))
4781 error ("%qT is not an accessible base of %qT",
4782 BINFO_TYPE (cand->conversion_path),
4783 TREE_TYPE (argtype));
4784 /* If fn was found by a using declaration, the conversion path
4785 will be to the derived class, not the base declaring fn. We
4786 must convert from derived to base. */
4787 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4788 TREE_TYPE (parmtype), ba_unique, NULL);
4789 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4792 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4793 parm = TREE_CHAIN (parm);
4794 arg = TREE_CHAIN (arg);
4800 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4802 tree type = TREE_VALUE (parm);
4805 val = convert_like_with_context
4806 (conv, TREE_VALUE (arg), fn, i - is_method);
4808 val = convert_for_arg_passing (type, val);
4809 converted_args = tree_cons (NULL_TREE, val, converted_args);
4812 /* Default arguments */
4813 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4815 = tree_cons (NULL_TREE,
4816 convert_default_arg (TREE_VALUE (parm),
4817 TREE_PURPOSE (parm),
4822 for (; arg; arg = TREE_CHAIN (arg))
4824 tree a = TREE_VALUE (arg);
4825 if (magic_varargs_p (fn))
4826 /* Do no conversions for magic varargs. */;
4828 a = convert_arg_to_ellipsis (a);
4829 converted_args = tree_cons (NULL_TREE, a, converted_args);
4832 converted_args = nreverse (converted_args);
4834 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4835 converted_args, TYPE_ARG_TYPES (TREE_TYPE (fn)));
4837 /* Avoid actually calling copy constructors and copy assignment operators,
4840 if (! flag_elide_constructors)
4841 /* Do things the hard way. */;
4842 else if (cand->num_convs == 1 && DECL_COPY_CONSTRUCTOR_P (fn))
4845 arg = skip_artificial_parms_for (fn, converted_args);
4846 arg = TREE_VALUE (arg);
4848 /* Pull out the real argument, disregarding const-correctness. */
4850 while (TREE_CODE (targ) == NOP_EXPR
4851 || TREE_CODE (targ) == NON_LVALUE_EXPR
4852 || TREE_CODE (targ) == CONVERT_EXPR)
4853 targ = TREE_OPERAND (targ, 0);
4854 if (TREE_CODE (targ) == ADDR_EXPR)
4856 targ = TREE_OPERAND (targ, 0);
4857 if (!same_type_ignoring_top_level_qualifiers_p
4858 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4867 arg = build_indirect_ref (arg, 0);
4869 /* [class.copy]: the copy constructor is implicitly defined even if
4870 the implementation elided its use. */
4871 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4874 /* If we're creating a temp and we already have one, don't create a
4875 new one. If we're not creating a temp but we get one, use
4876 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4877 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4878 temp or an INIT_EXPR otherwise. */
4879 if (integer_zerop (TREE_VALUE (args)))
4881 if (TREE_CODE (arg) == TARGET_EXPR)
4883 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4884 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4886 else if (TREE_CODE (arg) == TARGET_EXPR
4887 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4889 tree to = stabilize_reference
4890 (build_indirect_ref (TREE_VALUE (args), 0));
4892 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4896 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4898 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4900 tree to = stabilize_reference
4901 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4902 tree type = TREE_TYPE (to);
4903 tree as_base = CLASSTYPE_AS_BASE (type);
4905 arg = TREE_VALUE (TREE_CHAIN (converted_args));
4906 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
4908 arg = build_indirect_ref (arg, 0);
4909 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4913 /* We must only copy the non-tail padding parts.
4914 Use __builtin_memcpy for the bitwise copy. */
4918 args = tree_cons (NULL, TYPE_SIZE_UNIT (as_base), NULL);
4919 args = tree_cons (NULL, arg, args);
4920 t = build_unary_op (ADDR_EXPR, to, 0);
4921 args = tree_cons (NULL, t, args);
4922 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
4923 t = build_call (t, args);
4925 t = convert (TREE_TYPE (TREE_VALUE (args)), t);
4926 val = build_indirect_ref (t, 0);
4934 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4936 tree t, *p = &TREE_VALUE (converted_args);
4937 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4940 gcc_assert (binfo && binfo != error_mark_node);
4942 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4943 if (TREE_SIDE_EFFECTS (*p))
4944 *p = save_expr (*p);
4945 t = build_pointer_type (TREE_TYPE (fn));
4946 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4947 fn = build_java_interface_fn_ref (fn, *p);
4949 fn = build_vfn_ref (*p, DECL_VINDEX (fn));
4952 else if (DECL_INLINE (fn))
4953 fn = inline_conversion (fn);
4955 fn = build_addr_func (fn);
4957 return build_cxx_call (fn, converted_args);
4960 /* Build and return a call to FN, using ARGS. This function performs
4961 no overload resolution, conversion, or other high-level
4965 build_cxx_call (tree fn, tree args)
4969 fn = build_call (fn, args);
4971 /* If this call might throw an exception, note that fact. */
4972 fndecl = get_callee_fndecl (fn);
4973 if ((!fndecl || !TREE_NOTHROW (fndecl))
4974 && at_function_scope_p ()
4976 cp_function_chain->can_throw = 1;
4978 /* Some built-in function calls will be evaluated at compile-time in
4980 fn = fold_if_not_in_template (fn);
4982 if (VOID_TYPE_P (TREE_TYPE (fn)))
4985 fn = require_complete_type (fn);
4986 if (fn == error_mark_node)
4987 return error_mark_node;
4989 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4990 fn = build_cplus_new (TREE_TYPE (fn), fn);
4991 return convert_from_reference (fn);
4994 static GTY(()) tree java_iface_lookup_fn;
4996 /* Make an expression which yields the address of the Java interface
4997 method FN. This is achieved by generating a call to libjava's
4998 _Jv_LookupInterfaceMethodIdx(). */
5001 build_java_interface_fn_ref (tree fn, tree instance)
5003 tree lookup_args, lookup_fn, method, idx;
5004 tree klass_ref, iface, iface_ref;
5007 if (!java_iface_lookup_fn)
5009 tree endlink = build_void_list_node ();
5010 tree t = tree_cons (NULL_TREE, ptr_type_node,
5011 tree_cons (NULL_TREE, ptr_type_node,
5012 tree_cons (NULL_TREE, java_int_type_node,
5014 java_iface_lookup_fn
5015 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
5016 build_function_type (ptr_type_node, t),
5017 0, NOT_BUILT_IN, NULL, NULL_TREE);
5020 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5021 This is the first entry in the vtable. */
5022 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
5025 /* Get the java.lang.Class pointer for the interface being called. */
5026 iface = DECL_CONTEXT (fn);
5027 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
5028 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
5029 || DECL_CONTEXT (iface_ref) != iface)
5031 error ("could not find class$ field in java interface type %qT",
5033 return error_mark_node;
5035 iface_ref = build_address (iface_ref);
5036 iface_ref = convert (build_pointer_type (iface), iface_ref);
5038 /* Determine the itable index of FN. */
5040 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
5042 if (!DECL_VIRTUAL_P (method))
5048 idx = build_int_cst (NULL_TREE, i);
5050 lookup_args = tree_cons (NULL_TREE, klass_ref,
5051 tree_cons (NULL_TREE, iface_ref,
5052 build_tree_list (NULL_TREE, idx)));
5053 lookup_fn = build1 (ADDR_EXPR,
5054 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
5055 java_iface_lookup_fn);
5056 return build3 (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
5059 /* Returns the value to use for the in-charge parameter when making a
5060 call to a function with the indicated NAME.
5062 FIXME:Can't we find a neater way to do this mapping? */
5065 in_charge_arg_for_name (tree name)
5067 if (name == base_ctor_identifier
5068 || name == base_dtor_identifier)
5069 return integer_zero_node;
5070 else if (name == complete_ctor_identifier)
5071 return integer_one_node;
5072 else if (name == complete_dtor_identifier)
5073 return integer_two_node;
5074 else if (name == deleting_dtor_identifier)
5075 return integer_three_node;
5077 /* This function should only be called with one of the names listed
5083 /* Build a call to a constructor, destructor, or an assignment
5084 operator for INSTANCE, an expression with class type. NAME
5085 indicates the special member function to call; ARGS are the
5086 arguments. BINFO indicates the base of INSTANCE that is to be
5087 passed as the `this' parameter to the member function called.
5089 FLAGS are the LOOKUP_* flags to use when processing the call.
5091 If NAME indicates a complete object constructor, INSTANCE may be
5092 NULL_TREE. In this case, the caller will call build_cplus_new to
5093 store the newly constructed object into a VAR_DECL. */
5096 build_special_member_call (tree instance, tree name, tree args,
5097 tree binfo, int flags)
5100 /* The type of the subobject to be constructed or destroyed. */
5103 gcc_assert (name == complete_ctor_identifier
5104 || name == base_ctor_identifier
5105 || name == complete_dtor_identifier
5106 || name == base_dtor_identifier
5107 || name == deleting_dtor_identifier
5108 || name == ansi_assopname (NOP_EXPR));
5111 /* Resolve the name. */
5112 if (!complete_type_or_else (binfo, NULL_TREE))
5113 return error_mark_node;
5115 binfo = TYPE_BINFO (binfo);
5118 gcc_assert (binfo != NULL_TREE);
5120 class_type = BINFO_TYPE (binfo);
5122 /* Handle the special case where INSTANCE is NULL_TREE. */
5123 if (name == complete_ctor_identifier && !instance)
5125 instance = build_int_cst (build_pointer_type (class_type), 0);
5126 instance = build1 (INDIRECT_REF, class_type, instance);
5130 if (name == complete_dtor_identifier
5131 || name == base_dtor_identifier
5132 || name == deleting_dtor_identifier)
5133 gcc_assert (args == NULL_TREE);
5135 /* Convert to the base class, if necessary. */
5136 if (!same_type_ignoring_top_level_qualifiers_p
5137 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5139 if (name != ansi_assopname (NOP_EXPR))
5140 /* For constructors and destructors, either the base is
5141 non-virtual, or it is virtual but we are doing the
5142 conversion from a constructor or destructor for the
5143 complete object. In either case, we can convert
5145 instance = convert_to_base_statically (instance, binfo);
5147 /* However, for assignment operators, we must convert
5148 dynamically if the base is virtual. */
5149 instance = build_base_path (PLUS_EXPR, instance,
5150 binfo, /*nonnull=*/1);
5154 gcc_assert (instance != NULL_TREE);
5156 fns = lookup_fnfields (binfo, name, 1);
5158 /* When making a call to a constructor or destructor for a subobject
5159 that uses virtual base classes, pass down a pointer to a VTT for
5161 if ((name == base_ctor_identifier
5162 || name == base_dtor_identifier)
5163 && CLASSTYPE_VBASECLASSES (class_type))
5168 /* If the current function is a complete object constructor
5169 or destructor, then we fetch the VTT directly.
5170 Otherwise, we look it up using the VTT we were given. */
5171 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5172 vtt = decay_conversion (vtt);
5173 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5174 build2 (EQ_EXPR, boolean_type_node,
5175 current_in_charge_parm, integer_zero_node),
5178 gcc_assert (BINFO_SUBVTT_INDEX (binfo));
5179 sub_vtt = build2 (PLUS_EXPR, TREE_TYPE (vtt), vtt,
5180 BINFO_SUBVTT_INDEX (binfo));
5182 args = tree_cons (NULL_TREE, sub_vtt, args);
5185 return build_new_method_call (instance, fns, args,
5186 TYPE_BINFO (BINFO_TYPE (binfo)),
5190 /* Return the NAME, as a C string. The NAME indicates a function that
5191 is a member of TYPE. *FREE_P is set to true if the caller must
5192 free the memory returned.
5194 Rather than go through all of this, we should simply set the names
5195 of constructors and destructors appropriately, and dispense with
5196 ctor_identifier, dtor_identifier, etc. */
5199 name_as_c_string (tree name, tree type, bool *free_p)
5203 /* Assume that we will not allocate memory. */
5205 /* Constructors and destructors are special. */
5206 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5209 = (char *) IDENTIFIER_POINTER (constructor_name (type));
5210 /* For a destructor, add the '~'. */
5211 if (name == complete_dtor_identifier
5212 || name == base_dtor_identifier
5213 || name == deleting_dtor_identifier)
5215 pretty_name = concat ("~", pretty_name, NULL);
5216 /* Remember that we need to free the memory allocated. */
5220 else if (IDENTIFIER_TYPENAME_P (name))
5222 pretty_name = concat ("operator ",
5223 type_as_string (TREE_TYPE (name),
5224 TFF_PLAIN_IDENTIFIER),
5226 /* Remember that we need to free the memory allocated. */
5230 pretty_name = (char *) IDENTIFIER_POINTER (name);
5235 /* Build a call to "INSTANCE.FN (ARGS)". */
5238 build_new_method_call (tree instance, tree fns, tree args,
5239 tree conversion_path, int flags)
5241 struct z_candidate *candidates = 0, *cand;
5242 tree explicit_targs = NULL_TREE;
5243 tree basetype = NULL_TREE;
5246 tree mem_args = NULL_TREE, instance_ptr;
5252 int template_only = 0;
5259 gcc_assert (instance != NULL_TREE);
5261 if (error_operand_p (instance)
5262 || error_operand_p (fns)
5263 || args == error_mark_node)
5264 return error_mark_node;
5266 if (!BASELINK_P (fns))
5268 error ("call to non-function %qD", fns);
5269 return error_mark_node;
5272 orig_instance = instance;
5276 /* Dismantle the baselink to collect all the information we need. */
5277 if (!conversion_path)
5278 conversion_path = BASELINK_BINFO (fns);
5279 access_binfo = BASELINK_ACCESS_BINFO (fns);
5280 optype = BASELINK_OPTYPE (fns);
5281 fns = BASELINK_FUNCTIONS (fns);
5282 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5284 explicit_targs = TREE_OPERAND (fns, 1);
5285 fns = TREE_OPERAND (fns, 0);
5288 gcc_assert (TREE_CODE (fns) == FUNCTION_DECL
5289 || TREE_CODE (fns) == TEMPLATE_DECL
5290 || TREE_CODE (fns) == OVERLOAD);
5291 fn = get_first_fn (fns);
5292 name = DECL_NAME (fn);
5294 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5295 gcc_assert (CLASS_TYPE_P (basetype));
5297 if (processing_template_decl)
5299 instance = build_non_dependent_expr (instance);
5300 args = build_non_dependent_args (orig_args);
5303 /* The USER_ARGS are the arguments we will display to users if an
5304 error occurs. The USER_ARGS should not include any
5305 compiler-generated arguments. The "this" pointer hasn't been
5306 added yet. However, we must remove the VTT pointer if this is a
5307 call to a base-class constructor or destructor. */
5309 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5311 /* Callers should explicitly indicate whether they want to construct
5312 the complete object or just the part without virtual bases. */
5313 gcc_assert (name != ctor_identifier);
5314 /* Similarly for destructors. */
5315 gcc_assert (name != dtor_identifier);
5316 /* Remove the VTT pointer, if present. */
5317 if ((name == base_ctor_identifier || name == base_dtor_identifier)
5318 && CLASSTYPE_VBASECLASSES (basetype))
5319 user_args = TREE_CHAIN (user_args);
5322 /* Process the argument list. */
5323 args = resolve_args (args);
5324 if (args == error_mark_node)
5325 return error_mark_node;
5327 instance_ptr = build_this (instance);
5329 /* It's OK to call destructors on cv-qualified objects. Therefore,
5330 convert the INSTANCE_PTR to the unqualified type, if necessary. */
5331 if (DECL_DESTRUCTOR_P (fn))
5333 tree type = build_pointer_type (basetype);
5334 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5335 instance_ptr = build_nop (type, instance_ptr);
5336 name = complete_dtor_identifier;
5339 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5340 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5342 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5343 p = conversion_obstack_alloc (0);
5345 for (fn = fns; fn; fn = OVL_NEXT (fn))
5347 tree t = OVL_CURRENT (fn);
5350 /* We can end up here for copy-init of same or base class. */
5351 if ((flags & LOOKUP_ONLYCONVERTING)
5352 && DECL_NONCONVERTING_P (t))
5355 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5356 this_arglist = mem_args;
5358 this_arglist = args;
5360 if (TREE_CODE (t) == TEMPLATE_DECL)
5361 /* A member template. */
5362 add_template_candidate (&candidates, t,
5365 this_arglist, optype,
5370 else if (! template_only)
5371 add_function_candidate (&candidates, t,
5379 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5382 if (!COMPLETE_TYPE_P (basetype))
5383 cxx_incomplete_type_error (instance_ptr, basetype);
5389 pretty_name = name_as_c_string (name, basetype, &free_p);
5390 error ("no matching function for call to %<%T::%s(%A)%#V%>",
5391 basetype, pretty_name, user_args,
5392 TREE_TYPE (TREE_TYPE (instance_ptr)));
5396 print_z_candidates (candidates);
5397 call = error_mark_node;
5401 cand = tourney (candidates);
5407 pretty_name = name_as_c_string (name, basetype, &free_p);
5408 error ("call of overloaded %<%s(%A)%> is ambiguous", pretty_name,
5410 print_z_candidates (candidates);
5413 call = error_mark_node;
5417 if (!(flags & LOOKUP_NONVIRTUAL)
5418 && DECL_PURE_VIRTUAL_P (cand->fn)
5419 && instance == current_class_ref
5420 && (DECL_CONSTRUCTOR_P (current_function_decl)
5421 || DECL_DESTRUCTOR_P (current_function_decl)))
5422 /* This is not an error, it is runtime undefined
5424 warning (0, (DECL_CONSTRUCTOR_P (current_function_decl) ?
5425 "abstract virtual %q#D called from constructor"
5426 : "abstract virtual %q#D called from destructor"),
5429 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5430 && is_dummy_object (instance_ptr))
5432 error ("cannot call member function %qD without object",
5434 call = error_mark_node;
5438 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5439 && resolves_to_fixed_type_p (instance, 0))
5440 flags |= LOOKUP_NONVIRTUAL;
5442 call = build_over_call (cand, flags);
5444 /* In an expression of the form `a->f()' where `f' turns
5445 out to be a static member function, `a' is
5446 none-the-less evaluated. */
5447 if (TREE_CODE (TREE_TYPE (cand->fn)) != METHOD_TYPE
5448 && !is_dummy_object (instance_ptr)
5449 && TREE_SIDE_EFFECTS (instance))
5450 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5456 if (processing_template_decl && call != error_mark_node)
5457 call = (build_min_non_dep
5459 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5460 orig_args, NULL_TREE));
5462 /* Free all the conversions we allocated. */
5463 obstack_free (&conversion_obstack, p);
5468 /* Returns true iff standard conversion sequence ICS1 is a proper
5469 subsequence of ICS2. */
5472 is_subseq (conversion *ics1, conversion *ics2)
5474 /* We can assume that a conversion of the same code
5475 between the same types indicates a subsequence since we only get
5476 here if the types we are converting from are the same. */
5478 while (ics1->kind == ck_rvalue
5479 || ics1->kind == ck_lvalue)
5480 ics1 = ics1->u.next;
5484 while (ics2->kind == ck_rvalue
5485 || ics2->kind == ck_lvalue)
5486 ics2 = ics2->u.next;
5488 if (ics2->kind == ck_user
5489 || ics2->kind == ck_ambig
5490 || ics2->kind == ck_identity)
5491 /* At this point, ICS1 cannot be a proper subsequence of
5492 ICS2. We can get a USER_CONV when we are comparing the
5493 second standard conversion sequence of two user conversion
5497 ics2 = ics2->u.next;
5499 if (ics2->kind == ics1->kind
5500 && same_type_p (ics2->type, ics1->type)
5501 && same_type_p (ics2->u.next->type,
5502 ics1->u.next->type))
5507 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5508 be any _TYPE nodes. */
5511 is_properly_derived_from (tree derived, tree base)
5513 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5514 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5517 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5518 considers every class derived from itself. */
5519 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5520 && DERIVED_FROM_P (base, derived));
5523 /* We build the ICS for an implicit object parameter as a pointer
5524 conversion sequence. However, such a sequence should be compared
5525 as if it were a reference conversion sequence. If ICS is the
5526 implicit conversion sequence for an implicit object parameter,
5527 modify it accordingly. */
5530 maybe_handle_implicit_object (conversion **ics)
5534 /* [over.match.funcs]
5536 For non-static member functions, the type of the
5537 implicit object parameter is "reference to cv X"
5538 where X is the class of which the function is a
5539 member and cv is the cv-qualification on the member
5540 function declaration. */
5541 conversion *t = *ics;
5542 tree reference_type;
5544 /* The `this' parameter is a pointer to a class type. Make the
5545 implicit conversion talk about a reference to that same class
5547 reference_type = TREE_TYPE (t->type);
5548 reference_type = build_reference_type (reference_type);
5550 if (t->kind == ck_qual)
5552 if (t->kind == ck_ptr)
5554 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
5555 t = direct_reference_binding (reference_type, t);
5560 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5561 and return the type to which the reference refers. Otherwise,
5562 leave *ICS unchanged and return NULL_TREE. */
5565 maybe_handle_ref_bind (conversion **ics)
5567 if ((*ics)->kind == ck_ref_bind)
5569 conversion *old_ics = *ics;
5570 tree type = TREE_TYPE (old_ics->type);
5571 *ics = old_ics->u.next;
5572 (*ics)->user_conv_p = old_ics->user_conv_p;
5573 (*ics)->bad_p = old_ics->bad_p;
5580 /* Compare two implicit conversion sequences according to the rules set out in
5581 [over.ics.rank]. Return values:
5583 1: ics1 is better than ics2
5584 -1: ics2 is better than ics1
5585 0: ics1 and ics2 are indistinguishable */
5588 compare_ics (conversion *ics1, conversion *ics2)
5594 tree deref_from_type1 = NULL_TREE;
5595 tree deref_from_type2 = NULL_TREE;
5596 tree deref_to_type1 = NULL_TREE;
5597 tree deref_to_type2 = NULL_TREE;
5598 conversion_rank rank1, rank2;
5600 /* REF_BINDING is nonzero if the result of the conversion sequence
5601 is a reference type. In that case TARGET_TYPE is the
5602 type referred to by the reference. */
5606 /* Handle implicit object parameters. */
5607 maybe_handle_implicit_object (&ics1);
5608 maybe_handle_implicit_object (&ics2);
5610 /* Handle reference parameters. */
5611 target_type1 = maybe_handle_ref_bind (&ics1);
5612 target_type2 = maybe_handle_ref_bind (&ics2);
5616 When comparing the basic forms of implicit conversion sequences (as
5617 defined in _over.best.ics_)
5619 --a standard conversion sequence (_over.ics.scs_) is a better
5620 conversion sequence than a user-defined conversion sequence
5621 or an ellipsis conversion sequence, and
5623 --a user-defined conversion sequence (_over.ics.user_) is a
5624 better conversion sequence than an ellipsis conversion sequence
5625 (_over.ics.ellipsis_). */
5626 rank1 = CONVERSION_RANK (ics1);
5627 rank2 = CONVERSION_RANK (ics2);
5631 else if (rank1 < rank2)
5634 if (rank1 == cr_bad)
5636 /* XXX Isn't this an extension? */
5637 /* Both ICS are bad. We try to make a decision based on what
5638 would have happened if they'd been good. */
5639 if (ics1->user_conv_p > ics2->user_conv_p
5640 || ics1->rank > ics2->rank)
5642 else if (ics1->user_conv_p < ics2->user_conv_p
5643 || ics1->rank < ics2->rank)
5646 /* We couldn't make up our minds; try to figure it out below. */
5649 if (ics1->ellipsis_p)
5650 /* Both conversions are ellipsis conversions. */
5653 /* User-defined conversion sequence U1 is a better conversion sequence
5654 than another user-defined conversion sequence U2 if they contain the
5655 same user-defined conversion operator or constructor and if the sec-
5656 ond standard conversion sequence of U1 is better than the second
5657 standard conversion sequence of U2. */
5659 if (ics1->user_conv_p)
5664 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
5665 if (t1->kind == ck_ambig)
5667 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
5668 if (t2->kind == ck_ambig)
5671 if (t1->cand->fn != t2->cand->fn)
5674 /* We can just fall through here, after setting up
5675 FROM_TYPE1 and FROM_TYPE2. */
5676 from_type1 = t1->type;
5677 from_type2 = t2->type;
5684 /* We're dealing with two standard conversion sequences.
5688 Standard conversion sequence S1 is a better conversion
5689 sequence than standard conversion sequence S2 if
5691 --S1 is a proper subsequence of S2 (comparing the conversion
5692 sequences in the canonical form defined by _over.ics.scs_,
5693 excluding any Lvalue Transformation; the identity
5694 conversion sequence is considered to be a subsequence of
5695 any non-identity conversion sequence */
5698 while (t1->kind != ck_identity)
5700 from_type1 = t1->type;
5703 while (t2->kind != ck_identity)
5705 from_type2 = t2->type;
5708 if (same_type_p (from_type1, from_type2))
5710 if (is_subseq (ics1, ics2))
5712 if (is_subseq (ics2, ics1))
5715 /* Otherwise, one sequence cannot be a subsequence of the other; they
5716 don't start with the same type. This can happen when comparing the
5717 second standard conversion sequence in two user-defined conversion
5724 --the rank of S1 is better than the rank of S2 (by the rules
5727 Standard conversion sequences are ordered by their ranks: an Exact
5728 Match is a better conversion than a Promotion, which is a better
5729 conversion than a Conversion.
5731 Two conversion sequences with the same rank are indistinguishable
5732 unless one of the following rules applies:
5734 --A conversion that is not a conversion of a pointer, or pointer
5735 to member, to bool is better than another conversion that is such
5738 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5739 so that we do not have to check it explicitly. */
5740 if (ics1->rank < ics2->rank)
5742 else if (ics2->rank < ics1->rank)
5745 to_type1 = ics1->type;
5746 to_type2 = ics2->type;
5748 if (TYPE_PTR_P (from_type1)
5749 && TYPE_PTR_P (from_type2)
5750 && TYPE_PTR_P (to_type1)
5751 && TYPE_PTR_P (to_type2))
5753 deref_from_type1 = TREE_TYPE (from_type1);
5754 deref_from_type2 = TREE_TYPE (from_type2);
5755 deref_to_type1 = TREE_TYPE (to_type1);
5756 deref_to_type2 = TREE_TYPE (to_type2);
5758 /* The rules for pointers to members A::* are just like the rules
5759 for pointers A*, except opposite: if B is derived from A then
5760 A::* converts to B::*, not vice versa. For that reason, we
5761 switch the from_ and to_ variables here. */
5762 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5763 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5764 || (TYPE_PTRMEMFUNC_P (from_type1)
5765 && TYPE_PTRMEMFUNC_P (from_type2)
5766 && TYPE_PTRMEMFUNC_P (to_type1)
5767 && TYPE_PTRMEMFUNC_P (to_type2)))
5769 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5770 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5771 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5772 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5775 if (deref_from_type1 != NULL_TREE
5776 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5777 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5779 /* This was one of the pointer or pointer-like conversions.
5783 --If class B is derived directly or indirectly from class A,
5784 conversion of B* to A* is better than conversion of B* to
5785 void*, and conversion of A* to void* is better than
5786 conversion of B* to void*. */
5787 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5788 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5790 if (is_properly_derived_from (deref_from_type1,
5793 else if (is_properly_derived_from (deref_from_type2,
5797 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5798 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5800 if (same_type_p (deref_from_type1, deref_from_type2))
5802 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5804 if (is_properly_derived_from (deref_from_type1,
5808 /* We know that DEREF_TO_TYPE1 is `void' here. */
5809 else if (is_properly_derived_from (deref_from_type1,
5814 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5815 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5819 --If class B is derived directly or indirectly from class A
5820 and class C is derived directly or indirectly from B,
5822 --conversion of C* to B* is better than conversion of C* to
5825 --conversion of B* to A* is better than conversion of C* to
5827 if (same_type_p (deref_from_type1, deref_from_type2))
5829 if (is_properly_derived_from (deref_to_type1,
5832 else if (is_properly_derived_from (deref_to_type2,
5836 else if (same_type_p (deref_to_type1, deref_to_type2))
5838 if (is_properly_derived_from (deref_from_type2,
5841 else if (is_properly_derived_from (deref_from_type1,
5847 else if (CLASS_TYPE_P (non_reference (from_type1))
5848 && same_type_p (from_type1, from_type2))
5850 tree from = non_reference (from_type1);
5854 --binding of an expression of type C to a reference of type
5855 B& is better than binding an expression of type C to a
5856 reference of type A&
5858 --conversion of C to B is better than conversion of C to A, */
5859 if (is_properly_derived_from (from, to_type1)
5860 && is_properly_derived_from (from, to_type2))
5862 if (is_properly_derived_from (to_type1, to_type2))
5864 else if (is_properly_derived_from (to_type2, to_type1))
5868 else if (CLASS_TYPE_P (non_reference (to_type1))
5869 && same_type_p (to_type1, to_type2))
5871 tree to = non_reference (to_type1);
5875 --binding of an expression of type B to a reference of type
5876 A& is better than binding an expression of type C to a
5877 reference of type A&,
5879 --conversion of B to A is better than conversion of C to A */
5880 if (is_properly_derived_from (from_type1, to)
5881 && is_properly_derived_from (from_type2, to))
5883 if (is_properly_derived_from (from_type2, from_type1))
5885 else if (is_properly_derived_from (from_type1, from_type2))
5892 --S1 and S2 differ only in their qualification conversion and yield
5893 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5894 qualification signature of type T1 is a proper subset of the cv-
5895 qualification signature of type T2 */
5896 if (ics1->kind == ck_qual
5897 && ics2->kind == ck_qual
5898 && same_type_p (from_type1, from_type2))
5899 return comp_cv_qual_signature (to_type1, to_type2);
5903 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5904 types to which the references refer are the same type except for
5905 top-level cv-qualifiers, and the type to which the reference
5906 initialized by S2 refers is more cv-qualified than the type to
5907 which the reference initialized by S1 refers */
5909 if (target_type1 && target_type2
5910 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5911 return comp_cv_qualification (target_type2, target_type1);
5913 /* Neither conversion sequence is better than the other. */
5917 /* The source type for this standard conversion sequence. */
5920 source_type (conversion *t)
5922 for (;; t = t->u.next)
5924 if (t->kind == ck_user
5925 || t->kind == ck_ambig
5926 || t->kind == ck_identity)
5932 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5933 a pointer to LOSER and re-running joust to produce the warning if WINNER
5934 is actually used. */
5937 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5939 candidate_warning *cw;
5941 cw = conversion_obstack_alloc (sizeof (candidate_warning));
5943 cw->next = winner->warnings;
5944 winner->warnings = cw;
5947 /* Compare two candidates for overloading as described in
5948 [over.match.best]. Return values:
5950 1: cand1 is better than cand2
5951 -1: cand2 is better than cand1
5952 0: cand1 and cand2 are indistinguishable */
5955 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5958 int off1 = 0, off2 = 0;
5962 /* Candidates that involve bad conversions are always worse than those
5964 if (cand1->viable > cand2->viable)
5966 if (cand1->viable < cand2->viable)
5969 /* If we have two pseudo-candidates for conversions to the same type,
5970 or two candidates for the same function, arbitrarily pick one. */
5971 if (cand1->fn == cand2->fn
5972 && (IS_TYPE_OR_DECL_P (cand1->fn)))
5975 /* a viable function F1
5976 is defined to be a better function than another viable function F2 if
5977 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5978 ICSi(F2), and then */
5980 /* for some argument j, ICSj(F1) is a better conversion sequence than
5983 /* For comparing static and non-static member functions, we ignore
5984 the implicit object parameter of the non-static function. The
5985 standard says to pretend that the static function has an object
5986 parm, but that won't work with operator overloading. */
5987 len = cand1->num_convs;
5988 if (len != cand2->num_convs)
5990 int static_1 = DECL_STATIC_FUNCTION_P (cand1->fn);
5991 int static_2 = DECL_STATIC_FUNCTION_P (cand2->fn);
5993 gcc_assert (static_1 != static_2);
6004 for (i = 0; i < len; ++i)
6006 conversion *t1 = cand1->convs[i + off1];
6007 conversion *t2 = cand2->convs[i + off2];
6008 int comp = compare_ics (t1, t2);
6013 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
6014 == cr_std + cr_promotion)
6015 && t1->kind == ck_std
6016 && t2->kind == ck_std
6017 && TREE_CODE (t1->type) == INTEGER_TYPE
6018 && TREE_CODE (t2->type) == INTEGER_TYPE
6019 && (TYPE_PRECISION (t1->type)
6020 == TYPE_PRECISION (t2->type))
6021 && (TYPE_UNSIGNED (t1->u.next->type)
6022 || (TREE_CODE (t1->u.next->type)
6025 tree type = t1->u.next->type;
6027 struct z_candidate *w, *l;
6029 type1 = t1->type, type2 = t2->type,
6030 w = cand1, l = cand2;
6032 type1 = t2->type, type2 = t1->type,
6033 w = cand2, l = cand1;
6037 warning (0, "passing %qT chooses %qT over %qT",
6038 type, type1, type2);
6039 warning (0, " in call to %qD", w->fn);
6045 if (winner && comp != winner)
6054 /* warn about confusing overload resolution for user-defined conversions,
6055 either between a constructor and a conversion op, or between two
6057 if (winner && warn_conversion && cand1->second_conv
6058 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
6059 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
6061 struct z_candidate *w, *l;
6062 bool give_warning = false;
6065 w = cand1, l = cand2;
6067 w = cand2, l = cand1;
6069 /* We don't want to complain about `X::operator T1 ()'
6070 beating `X::operator T2 () const', when T2 is a no less
6071 cv-qualified version of T1. */
6072 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
6073 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
6075 tree t = TREE_TYPE (TREE_TYPE (l->fn));
6076 tree f = TREE_TYPE (TREE_TYPE (w->fn));
6078 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6083 if (!comp_ptr_ttypes (t, f))
6084 give_warning = true;
6087 give_warning = true;
6093 tree source = source_type (w->convs[0]);
6094 if (! DECL_CONSTRUCTOR_P (w->fn))
6095 source = TREE_TYPE (source);
6096 warning (0, "choosing %qD over %qD", w->fn, l->fn);
6097 warning (0, " for conversion from %qT to %qT",
6098 source, w->second_conv->type);
6099 warning (0, " because conversion sequence for the argument is better");
6109 F1 is a non-template function and F2 is a template function
6112 if (!cand1->template_decl && cand2->template_decl)
6114 else if (cand1->template_decl && !cand2->template_decl)
6118 F1 and F2 are template functions and the function template for F1 is
6119 more specialized than the template for F2 according to the partial
6122 if (cand1->template_decl && cand2->template_decl)
6124 winner = more_specialized_fn
6125 (TI_TEMPLATE (cand1->template_decl),
6126 TI_TEMPLATE (cand2->template_decl),
6127 /* [temp.func.order]: The presence of unused ellipsis and default
6128 arguments has no effect on the partial ordering of function
6129 templates. add_function_candidate() will not have
6130 counted the "this" argument for constructors. */
6131 cand1->num_convs + DECL_CONSTRUCTOR_P (cand1->fn));
6137 the context is an initialization by user-defined conversion (see
6138 _dcl.init_ and _over.match.user_) and the standard conversion
6139 sequence from the return type of F1 to the destination type (i.e.,
6140 the type of the entity being initialized) is a better conversion
6141 sequence than the standard conversion sequence from the return type
6142 of F2 to the destination type. */
6144 if (cand1->second_conv)
6146 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6151 /* Check whether we can discard a builtin candidate, either because we
6152 have two identical ones or matching builtin and non-builtin candidates.
6154 (Pedantically in the latter case the builtin which matched the user
6155 function should not be added to the overload set, but we spot it here.
6158 ... the builtin candidates include ...
6159 - do not have the same parameter type list as any non-template
6160 non-member candidate. */
6162 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6163 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6165 for (i = 0; i < len; ++i)
6166 if (!same_type_p (cand1->convs[i]->type,
6167 cand2->convs[i]->type))
6169 if (i == cand1->num_convs)
6171 if (cand1->fn == cand2->fn)
6172 /* Two built-in candidates; arbitrarily pick one. */
6174 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6175 /* cand1 is built-in; prefer cand2. */
6178 /* cand2 is built-in; prefer cand1. */
6183 /* If the two functions are the same (this can happen with declarations
6184 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6185 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6186 && equal_functions (cand1->fn, cand2->fn))
6191 /* Extension: If the worst conversion for one candidate is worse than the
6192 worst conversion for the other, take the first. */
6195 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6196 struct z_candidate *w = 0, *l = 0;
6198 for (i = 0; i < len; ++i)
6200 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6201 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6202 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6203 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6206 winner = 1, w = cand1, l = cand2;
6208 winner = -1, w = cand2, l = cand1;
6214 ISO C++ says that these are ambiguous, even \
6215 though the worst conversion for the first is better than \
6216 the worst conversion for the second:");
6217 print_z_candidate (_("candidate 1:"), w);
6218 print_z_candidate (_("candidate 2:"), l);
6226 gcc_assert (!winner);
6230 /* Given a list of candidates for overloading, find the best one, if any.
6231 This algorithm has a worst case of O(2n) (winner is last), and a best
6232 case of O(n/2) (totally ambiguous); much better than a sorting
6235 static struct z_candidate *
6236 tourney (struct z_candidate *candidates)
6238 struct z_candidate *champ = candidates, *challenger;
6240 int champ_compared_to_predecessor = 0;
6242 /* Walk through the list once, comparing each current champ to the next
6243 candidate, knocking out a candidate or two with each comparison. */
6245 for (challenger = champ->next; challenger; )
6247 fate = joust (champ, challenger, 0);
6249 challenger = challenger->next;
6254 champ = challenger->next;
6257 champ_compared_to_predecessor = 0;
6262 champ_compared_to_predecessor = 1;
6265 challenger = champ->next;
6269 /* Make sure the champ is better than all the candidates it hasn't yet
6270 been compared to. */
6272 for (challenger = candidates;
6274 && !(champ_compared_to_predecessor && challenger->next == champ);
6275 challenger = challenger->next)
6277 fate = joust (champ, challenger, 0);
6285 /* Returns nonzero if things of type FROM can be converted to TO. */
6288 can_convert (tree to, tree from)
6290 return can_convert_arg (to, from, NULL_TREE, LOOKUP_NORMAL);
6293 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6296 can_convert_arg (tree to, tree from, tree arg, int flags)
6302 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6303 p = conversion_obstack_alloc (0);
6305 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6307 ok_p = (t && !t->bad_p);
6309 /* Free all the conversions we allocated. */
6310 obstack_free (&conversion_obstack, p);
6315 /* Like can_convert_arg, but allows dubious conversions as well. */
6318 can_convert_arg_bad (tree to, tree from, tree arg)
6323 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6324 p = conversion_obstack_alloc (0);
6325 /* Try to perform the conversion. */
6326 t = implicit_conversion (to, from, arg, /*c_cast_p=*/false,
6328 /* Free all the conversions we allocated. */
6329 obstack_free (&conversion_obstack, p);
6334 /* Convert EXPR to TYPE. Return the converted expression.
6336 Note that we allow bad conversions here because by the time we get to
6337 this point we are committed to doing the conversion. If we end up
6338 doing a bad conversion, convert_like will complain. */
6341 perform_implicit_conversion (tree type, tree expr)
6346 if (error_operand_p (expr))
6347 return error_mark_node;
6349 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6350 p = conversion_obstack_alloc (0);
6352 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6357 error ("could not convert %qE to %qT", expr, type);
6358 expr = error_mark_node;
6361 expr = convert_like (conv, expr);
6363 /* Free all the conversions we allocated. */
6364 obstack_free (&conversion_obstack, p);
6369 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6370 permitted. If the conversion is valid, the converted expression is
6371 returned. Otherwise, NULL_TREE is returned, except in the case
6372 that TYPE is a class type; in that case, an error is issued. If
6373 C_CAST_P is true, then this direction initialization is taking
6374 place as part of a static_cast being attempted as part of a C-style
6378 perform_direct_initialization_if_possible (tree type,
6385 if (type == error_mark_node || error_operand_p (expr))
6386 return error_mark_node;
6389 If the destination type is a (possibly cv-qualified) class type:
6391 -- If the initialization is direct-initialization ...,
6392 constructors are considered. ... If no constructor applies, or
6393 the overload resolution is ambiguous, the initialization is
6395 if (CLASS_TYPE_P (type))
6397 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6398 build_tree_list (NULL_TREE, expr),
6399 type, LOOKUP_NORMAL);
6400 return build_cplus_new (type, expr);
6403 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6404 p = conversion_obstack_alloc (0);
6406 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6409 if (!conv || conv->bad_p)
6412 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6413 /*issue_conversion_warnings=*/false,
6416 /* Free all the conversions we allocated. */
6417 obstack_free (&conversion_obstack, p);
6422 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6423 is being bound to a temporary. Create and return a new VAR_DECL
6424 with the indicated TYPE; this variable will store the value to
6425 which the reference is bound. */
6428 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6432 /* Create the variable. */
6433 var = create_temporary_var (type);
6435 /* Register the variable. */
6436 if (TREE_STATIC (decl))
6438 /* Namespace-scope or local static; give it a mangled name. */
6441 TREE_STATIC (var) = 1;
6442 name = mangle_ref_init_variable (decl);
6443 DECL_NAME (var) = name;
6444 SET_DECL_ASSEMBLER_NAME (var, name);
6445 var = pushdecl_top_level (var);
6448 /* Create a new cleanup level if necessary. */
6449 maybe_push_cleanup_level (type);
6454 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6455 initializing a variable of that TYPE. If DECL is non-NULL, it is
6456 the VAR_DECL being initialized with the EXPR. (In that case, the
6457 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6458 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6459 return, if *CLEANUP is no longer NULL, it will be an expression
6460 that should be pushed as a cleanup after the returned expression
6461 is used to initialize DECL.
6463 Return the converted expression. */
6466 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6471 if (type == error_mark_node || error_operand_p (expr))
6472 return error_mark_node;
6474 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6475 p = conversion_obstack_alloc (0);
6477 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6478 if (!conv || conv->bad_p)
6480 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6481 && !real_lvalue_p (expr))
6482 error ("invalid initialization of non-const reference of "
6483 "type %qT from a temporary of type %qT",
6484 type, TREE_TYPE (expr));
6486 error ("invalid initialization of reference of type "
6487 "%qT from expression of type %qT", type,
6489 return error_mark_node;
6492 /* If DECL is non-NULL, then this special rule applies:
6496 The temporary to which the reference is bound or the temporary
6497 that is the complete object to which the reference is bound
6498 persists for the lifetime of the reference.
6500 The temporaries created during the evaluation of the expression
6501 initializing the reference, except the temporary to which the
6502 reference is bound, are destroyed at the end of the
6503 full-expression in which they are created.
6505 In that case, we store the converted expression into a new
6506 VAR_DECL in a new scope.
6508 However, we want to be careful not to create temporaries when
6509 they are not required. For example, given:
6512 struct D : public B {};
6516 there is no need to copy the return value from "f"; we can just
6517 extend its lifetime. Similarly, given:
6520 struct T { operator S(); };
6524 we can extend the lifetime of the return value of the conversion
6526 gcc_assert (conv->kind == ck_ref_bind);
6530 tree base_conv_type;
6532 /* Skip over the REF_BIND. */
6533 conv = conv->u.next;
6534 /* If the next conversion is a BASE_CONV, skip that too -- but
6535 remember that the conversion was required. */
6536 if (conv->kind == ck_base)
6538 if (conv->check_copy_constructor_p)
6539 check_constructor_callable (TREE_TYPE (expr), expr);
6540 base_conv_type = conv->type;
6541 conv = conv->u.next;
6544 base_conv_type = NULL_TREE;
6545 /* Perform the remainder of the conversion. */
6546 expr = convert_like_real (conv, expr,
6547 /*fn=*/NULL_TREE, /*argnum=*/0,
6549 /*issue_conversion_warnings=*/true,
6550 /*c_cast_p=*/false);
6551 if (error_operand_p (expr))
6552 expr = error_mark_node;
6555 if (!real_lvalue_p (expr))
6560 /* Create the temporary variable. */
6561 type = TREE_TYPE (expr);
6562 var = make_temporary_var_for_ref_to_temp (decl, type);
6563 layout_decl (var, 0);
6564 /* If the rvalue is the result of a function call it will be
6565 a TARGET_EXPR. If it is some other construct (such as a
6566 member access expression where the underlying object is
6567 itself the result of a function call), turn it into a
6568 TARGET_EXPR here. It is important that EXPR be a
6569 TARGET_EXPR below since otherwise the INIT_EXPR will
6570 attempt to make a bitwise copy of EXPR to initialize
6572 if (TREE_CODE (expr) != TARGET_EXPR)
6573 expr = get_target_expr (expr);
6574 /* Create the INIT_EXPR that will initialize the temporary
6576 init = build2 (INIT_EXPR, type, var, expr);
6577 if (at_function_scope_p ())
6579 add_decl_expr (var);
6580 *cleanup = cxx_maybe_build_cleanup (var);
6582 /* We must be careful to destroy the temporary only
6583 after its initialization has taken place. If the
6584 initialization throws an exception, then the
6585 destructor should not be run. We cannot simply
6586 transform INIT into something like:
6588 (INIT, ({ CLEANUP_STMT; }))
6590 because emit_local_var always treats the
6591 initializer as a full-expression. Thus, the
6592 destructor would run too early; it would run at the
6593 end of initializing the reference variable, rather
6594 than at the end of the block enclosing the
6597 The solution is to pass back a cleanup expression
6598 which the caller is responsible for attaching to
6599 the statement tree. */
6603 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
6604 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6605 static_aggregates = tree_cons (NULL_TREE, var,
6608 /* Use its address to initialize the reference variable. */
6609 expr = build_address (var);
6611 expr = convert_to_base (expr,
6612 build_pointer_type (base_conv_type),
6613 /*check_access=*/true,
6615 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6618 /* Take the address of EXPR. */
6619 expr = build_unary_op (ADDR_EXPR, expr, 0);
6620 /* If a BASE_CONV was required, perform it now. */
6622 expr = (perform_implicit_conversion
6623 (build_pointer_type (base_conv_type), expr));
6624 expr = build_nop (type, expr);
6628 /* Perform the conversion. */
6629 expr = convert_like (conv, expr);
6631 /* Free all the conversions we allocated. */
6632 obstack_free (&conversion_obstack, p);
6637 #include "gt-cp-call.h"