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 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, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, 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 an 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 /* The type of the expression resulting from the conversion. */
98 /* The next conversion in the chain. Since the conversions are
99 arranged from outermost to innermost, the NEXT conversion will
100 actually be performed before this conversion. This variant is
101 used only when KIND is neither ck_identity nor ck_ambig. */
103 /* The expression at the beginning of the conversion chain. This
104 variant is used only if KIND is ck_identity or ck_ambig. */
107 /* The function candidate corresponding to this conversion
108 sequence. This field is only used if KIND is ck_user. */
109 struct z_candidate *cand;
112 #define CONVERSION_RANK(NODE) \
113 ((NODE)->bad_p ? cr_bad \
114 : (NODE)->ellipsis_p ? cr_ellipsis \
115 : (NODE)->user_conv_p ? cr_user \
118 static struct obstack conversion_obstack;
119 static bool conversion_obstack_initialized;
121 static struct z_candidate * tourney (struct z_candidate *);
122 static int equal_functions (tree, tree);
123 static int joust (struct z_candidate *, struct z_candidate *, bool);
124 static int compare_ics (conversion *, conversion *);
125 static tree build_over_call (struct z_candidate *, int);
126 static tree build_java_interface_fn_ref (tree, tree);
127 #define convert_like(CONV, EXPR) \
128 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
129 /*issue_conversion_warnings=*/true)
130 #define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
131 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
132 /*issue_conversion_warnings=*/true)
133 static tree convert_like_real (conversion *, tree, tree, int, int, bool);
134 static void op_error (enum tree_code, enum tree_code, tree, tree,
136 static tree build_object_call (tree, tree);
137 static tree resolve_args (tree);
138 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
139 static void print_z_candidate (const char *, struct z_candidate *);
140 static void print_z_candidates (struct z_candidate *);
141 static tree build_this (tree);
142 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
143 static bool any_strictly_viable (struct z_candidate *);
144 static struct z_candidate *add_template_candidate
145 (struct z_candidate **, tree, tree, tree, tree, tree,
146 tree, tree, int, unification_kind_t);
147 static struct z_candidate *add_template_candidate_real
148 (struct z_candidate **, tree, tree, tree, tree, tree,
149 tree, tree, int, tree, unification_kind_t);
150 static struct z_candidate *add_template_conv_candidate
151 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
152 static void add_builtin_candidates
153 (struct z_candidate **, enum tree_code, enum tree_code,
155 static void add_builtin_candidate
156 (struct z_candidate **, enum tree_code, enum tree_code,
157 tree, tree, tree, tree *, tree *, int);
158 static bool is_complete (tree);
159 static void build_builtin_candidate
160 (struct z_candidate **, tree, tree, tree, tree *, tree *,
162 static struct z_candidate *add_conv_candidate
163 (struct z_candidate **, tree, tree, tree, tree, tree);
164 static struct z_candidate *add_function_candidate
165 (struct z_candidate **, tree, tree, tree, tree, tree, int);
166 static conversion *implicit_conversion (tree, tree, tree, int);
167 static conversion *standard_conversion (tree, tree, tree);
168 static conversion *reference_binding (tree, tree, tree, int);
169 static conversion *build_conv (conversion_kind, tree, conversion *);
170 static bool is_subseq (conversion *, conversion *);
171 static tree maybe_handle_ref_bind (conversion **);
172 static void maybe_handle_implicit_object (conversion **);
173 static struct z_candidate *add_candidate
174 (struct z_candidate **, tree, tree, size_t,
175 conversion **, tree, tree, int);
176 static tree source_type (conversion *);
177 static void add_warning (struct z_candidate *, struct z_candidate *);
178 static bool reference_related_p (tree, tree);
179 static bool reference_compatible_p (tree, tree);
180 static conversion *convert_class_to_reference (tree, tree, tree);
181 static conversion *direct_reference_binding (tree, conversion *);
182 static bool promoted_arithmetic_type_p (tree);
183 static conversion *conditional_conversion (tree, tree);
184 static char *name_as_c_string (tree, tree, bool *);
185 static tree call_builtin_trap (void);
186 static tree prep_operand (tree);
187 static void add_candidates (tree, tree, tree, bool, tree, tree,
188 int, struct z_candidate **);
189 static conversion *merge_conversion_sequences (conversion *, conversion *);
190 static bool magic_varargs_p (tree);
191 static tree build_temp (tree, tree, int, void (**)(const char *, ...));
192 static void check_constructor_callable (tree, tree);
195 build_vfield_ref (tree datum, tree type)
197 if (datum == error_mark_node)
198 return error_mark_node;
200 if (TREE_CODE (TREE_TYPE (datum)) == REFERENCE_TYPE)
201 datum = convert_from_reference (datum);
203 if (TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
204 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
205 datum = convert_to_base (datum, type, /*check_access=*/false);
207 return build3 (COMPONENT_REF, TREE_TYPE (TYPE_VFIELD (type)),
208 datum, TYPE_VFIELD (type), NULL_TREE);
211 /* Returns nonzero iff the destructor name specified in NAME
212 (a BIT_NOT_EXPR) matches BASETYPE. The operand of NAME can take many
216 check_dtor_name (tree basetype, tree name)
218 name = TREE_OPERAND (name, 0);
220 /* Just accept something we've already complained about. */
221 if (name == error_mark_node)
224 if (TREE_CODE (name) == TYPE_DECL)
225 name = TREE_TYPE (name);
226 else if (TYPE_P (name))
228 else if (TREE_CODE (name) == IDENTIFIER_NODE)
230 if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
231 || (TREE_CODE (basetype) == ENUMERAL_TYPE
232 && name == TYPE_IDENTIFIER (basetype)))
235 name = get_type_value (name);
239 template <class T> struct S { ~S(); };
243 NAME will be a class template. */
244 else if (DECL_CLASS_TEMPLATE_P (name))
249 if (name && TYPE_MAIN_VARIANT (basetype) == TYPE_MAIN_VARIANT (name))
254 /* We want the address of a function or method. We avoid creating a
255 pointer-to-member function. */
258 build_addr_func (tree function)
260 tree type = TREE_TYPE (function);
262 /* We have to do these by hand to avoid real pointer to member
264 if (TREE_CODE (type) == METHOD_TYPE)
266 if (TREE_CODE (function) == OFFSET_REF)
268 tree object = build_address (TREE_OPERAND (function, 0));
269 return get_member_function_from_ptrfunc (&object,
270 TREE_OPERAND (function, 1));
272 function = build_address (function);
275 function = decay_conversion (function);
280 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
281 POINTER_TYPE to those. Note, pointer to member function types
282 (TYPE_PTRMEMFUNC_P) must be handled by our callers. */
285 build_call (tree function, tree parms)
287 int is_constructor = 0;
294 function = build_addr_func (function);
296 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
298 sorry ("unable to call pointer to member function here");
299 return error_mark_node;
302 fntype = TREE_TYPE (TREE_TYPE (function));
303 result_type = TREE_TYPE (fntype);
305 if (TREE_CODE (function) == ADDR_EXPR
306 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
307 decl = TREE_OPERAND (function, 0);
311 /* We check both the decl and the type; a function may be known not to
312 throw without being declared throw(). */
313 nothrow = ((decl && TREE_NOTHROW (decl))
314 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
316 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
317 current_function_returns_abnormally = 1;
319 if (decl && TREE_DEPRECATED (decl))
320 warn_deprecated_use (decl);
321 require_complete_eh_spec_types (fntype, decl);
323 if (decl && DECL_CONSTRUCTOR_P (decl))
326 if (decl && ! TREE_USED (decl))
328 /* We invoke build_call directly for several library functions.
329 These may have been declared normally if we're building libgcc,
330 so we can't just check DECL_ARTIFICIAL. */
331 if (DECL_ARTIFICIAL (decl)
332 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), "__", 2))
338 /* Don't pass empty class objects by value. This is useful
339 for tags in STL, which are used to control overload resolution.
340 We don't need to handle other cases of copying empty classes. */
341 if (! decl || ! DECL_BUILT_IN (decl))
342 for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
343 if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
344 && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
346 tree t = build0 (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
347 TREE_VALUE (tmp) = build2 (COMPOUND_EXPR, TREE_TYPE (t),
348 TREE_VALUE (tmp), t);
351 function = build3 (CALL_EXPR, result_type, function, parms, NULL_TREE);
352 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
353 TREE_NOTHROW (function) = nothrow;
358 /* Build something of the form ptr->method (args)
359 or object.method (args). This can also build
360 calls to constructors, and find friends.
362 Member functions always take their class variable
365 INSTANCE is a class instance.
367 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
369 PARMS help to figure out what that NAME really refers to.
371 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
372 down to the real instance type to use for access checking. We need this
373 information to get protected accesses correct.
375 FLAGS is the logical disjunction of zero or more LOOKUP_
376 flags. See cp-tree.h for more info.
378 If this is all OK, calls build_function_call with the resolved
381 This function must also handle being called to perform
382 initialization, promotion/coercion of arguments, and
383 instantiation of default parameters.
385 Note that NAME may refer to an instance variable name. If
386 `operator()()' is defined for the type of that field, then we return
389 /* New overloading code. */
391 typedef struct z_candidate z_candidate;
393 typedef struct candidate_warning candidate_warning;
394 struct candidate_warning {
396 candidate_warning *next;
400 /* The FUNCTION_DECL that will be called if this candidate is
401 selected by overload resolution. */
403 /* The arguments to use when calling this function. */
405 /* The implicit conversion sequences for each of the arguments to
408 /* The number of implicit conversion sequences. */
410 /* If FN is a user-defined conversion, the standard conversion
411 sequence from the type returned by FN to the desired destination
413 conversion *second_conv;
415 /* If FN is a member function, the binfo indicating the path used to
416 qualify the name of FN at the call site. This path is used to
417 determine whether or not FN is accessible if it is selected by
418 overload resolution. The DECL_CONTEXT of FN will always be a
419 (possibly improper) base of this binfo. */
421 /* If FN is a non-static member function, the binfo indicating the
422 subobject to which the `this' pointer should be converted if FN
423 is selected by overload resolution. The type pointed to the by
424 the `this' pointer must correspond to the most derived class
425 indicated by the CONVERSION_PATH. */
426 tree conversion_path;
428 candidate_warning *warnings;
432 /* Returns true iff T is a null pointer constant in the sense of
436 null_ptr_cst_p (tree t)
440 A null pointer constant is an integral constant expression
441 (_expr.const_) rvalue of integer type that evaluates to zero. */
442 if (DECL_INTEGRAL_CONSTANT_VAR_P (t))
443 t = decl_constant_value (t);
445 || (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
450 /* Returns nonzero if PARMLIST consists of only default parms and/or
454 sufficient_parms_p (tree parmlist)
456 for (; parmlist && parmlist != void_list_node;
457 parmlist = TREE_CHAIN (parmlist))
458 if (!TREE_PURPOSE (parmlist))
463 /* Allocate N bytes of memory from the conversion obstack. The memory
464 is zeroed before being returned. */
467 conversion_obstack_alloc (size_t n)
470 if (!conversion_obstack_initialized)
472 gcc_obstack_init (&conversion_obstack);
473 conversion_obstack_initialized = true;
475 p = obstack_alloc (&conversion_obstack, n);
480 /* Dynamically allocate a conversion. */
483 alloc_conversion (conversion_kind kind)
486 c = conversion_obstack_alloc (sizeof (conversion));
491 #ifdef ENABLE_CHECKING
493 /* Make sure that all memory on the conversion obstack has been
497 validate_conversion_obstack (void)
499 if (conversion_obstack_initialized)
500 my_friendly_assert ((obstack_next_free (&conversion_obstack)
501 == obstack_base (&conversion_obstack)),
505 #endif /* ENABLE_CHECKING */
507 /* Dynamically allocate an array of N conversions. */
510 alloc_conversions (size_t n)
512 return conversion_obstack_alloc (n * sizeof (conversion *));
516 build_conv (conversion_kind code, tree type, conversion *from)
519 conversion_rank rank = CONVERSION_RANK (from);
521 /* We can't use buildl1 here because CODE could be USER_CONV, which
522 takes two arguments. In that case, the caller is responsible for
523 filling in the second argument. */
524 t = alloc_conversion (code);
547 t->user_conv_p = (code == ck_user || from->user_conv_p);
548 t->bad_p = from->bad_p;
552 /* Build a representation of the identity conversion from EXPR to
553 itself. The TYPE should match the the type of EXPR, if EXPR is
557 build_identity_conv (tree type, tree expr)
561 c = alloc_conversion (ck_identity);
568 /* Converting from EXPR to TYPE was ambiguous in the sense that there
569 were multiple user-defined conversions to accomplish the job.
570 Build a conversion that indicates that ambiguity. */
573 build_ambiguous_conv (tree type, tree expr)
577 c = alloc_conversion (ck_ambig);
585 strip_top_quals (tree t)
587 if (TREE_CODE (t) == ARRAY_TYPE)
589 return cp_build_qualified_type (t, 0);
592 /* Returns the standard conversion path (see [conv]) from type FROM to type
593 TO, if any. For proper handling of null pointer constants, you must
594 also pass the expression EXPR to convert from. */
597 standard_conversion (tree to, tree from, tree expr)
599 enum tree_code fcode, tcode;
601 bool fromref = false;
603 to = non_reference (to);
604 if (TREE_CODE (from) == REFERENCE_TYPE)
607 from = TREE_TYPE (from);
609 to = strip_top_quals (to);
610 from = strip_top_quals (from);
612 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
613 && expr && type_unknown_p (expr))
615 expr = instantiate_type (to, expr, tf_conv);
616 if (expr == error_mark_node)
618 from = TREE_TYPE (expr);
621 fcode = TREE_CODE (from);
622 tcode = TREE_CODE (to);
624 conv = build_identity_conv (from, expr);
625 if (fcode == FUNCTION_TYPE)
627 from = build_pointer_type (from);
628 fcode = TREE_CODE (from);
629 conv = build_conv (ck_lvalue, from, conv);
631 else if (fcode == ARRAY_TYPE)
633 from = build_pointer_type (TREE_TYPE (from));
634 fcode = TREE_CODE (from);
635 conv = build_conv (ck_lvalue, from, conv);
637 else if (fromref || (expr && lvalue_p (expr)))
638 conv = build_conv (ck_rvalue, from, conv);
640 /* Allow conversion between `__complex__' data types. */
641 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
643 /* The standard conversion sequence to convert FROM to TO is
644 the standard conversion sequence to perform componentwise
646 conversion *part_conv = standard_conversion
647 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE);
651 conv = build_conv (part_conv->kind, to, conv);
652 conv->rank = part_conv->rank;
660 if (same_type_p (from, to))
663 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
664 && expr && null_ptr_cst_p (expr))
665 conv = build_conv (ck_std, to, conv);
666 else if (tcode == POINTER_TYPE && fcode == POINTER_TYPE
667 && TREE_CODE (TREE_TYPE (to)) == VECTOR_TYPE
668 && TREE_CODE (TREE_TYPE (from)) == VECTOR_TYPE
669 && vector_types_convertible_p (TREE_TYPE (to), TREE_TYPE (from)))
670 conv = build_conv (ck_std, to, conv);
671 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
672 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
674 /* For backwards brain damage compatibility, allow interconversion of
675 pointers and integers with a pedwarn. */
676 conv = build_conv (ck_std, to, conv);
679 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
681 /* For backwards brain damage compatibility, allow interconversion of
682 enums and integers with a pedwarn. */
683 conv = build_conv (ck_std, to, conv);
686 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
687 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
692 if (tcode == POINTER_TYPE
693 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
696 else if (VOID_TYPE_P (TREE_TYPE (to))
697 && !TYPE_PTRMEM_P (from)
698 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
700 from = build_pointer_type
701 (cp_build_qualified_type (void_type_node,
702 cp_type_quals (TREE_TYPE (from))));
703 conv = build_conv (ck_ptr, from, conv);
705 else if (TYPE_PTRMEM_P (from))
707 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
708 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
710 if (DERIVED_FROM_P (fbase, tbase)
711 && (same_type_ignoring_top_level_qualifiers_p
712 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
713 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
715 from = build_ptrmem_type (tbase,
716 TYPE_PTRMEM_POINTED_TO_TYPE (from));
717 conv = build_conv (ck_pmem, from, conv);
719 else if (!same_type_p (fbase, tbase))
722 else if (IS_AGGR_TYPE (TREE_TYPE (from))
723 && IS_AGGR_TYPE (TREE_TYPE (to))
726 An rvalue of type "pointer to cv D," where D is a
727 class type, can be converted to an rvalue of type
728 "pointer to cv B," where B is a base class (clause
729 _class.derived_) of D. If B is an inaccessible
730 (clause _class.access_) or ambiguous
731 (_class.member.lookup_) base class of D, a program
732 that necessitates this conversion is ill-formed. */
733 /* Therefore, we use DERIVED_FROM_P, and not
734 ACCESSIBLY_UNIQUELY_DERIVED_FROM_P, in this test. */
735 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
738 cp_build_qualified_type (TREE_TYPE (to),
739 cp_type_quals (TREE_TYPE (from)));
740 from = build_pointer_type (from);
741 conv = build_conv (ck_ptr, from, conv);
744 if (tcode == POINTER_TYPE)
746 to_pointee = TREE_TYPE (to);
747 from_pointee = TREE_TYPE (from);
751 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
752 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
755 if (same_type_p (from, to))
757 else if (comp_ptr_ttypes (to_pointee, from_pointee))
758 conv = build_conv (ck_qual, to, conv);
759 else if (expr && string_conv_p (to, expr, 0))
760 /* converting from string constant to char *. */
761 conv = build_conv (ck_qual, to, conv);
762 else if (ptr_reasonably_similar (to_pointee, from_pointee))
764 conv = build_conv (ck_ptr, to, conv);
772 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
774 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
775 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
776 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
777 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
779 if (!DERIVED_FROM_P (fbase, tbase)
780 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
781 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
782 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
783 || cp_type_quals (fbase) != cp_type_quals (tbase))
786 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
787 from = build_method_type_directly (from,
789 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
790 from = build_ptrmemfunc_type (build_pointer_type (from));
791 conv = build_conv (ck_pmem, from, conv);
793 else if (tcode == BOOLEAN_TYPE)
797 An rvalue of arithmetic, enumeration, pointer, or pointer to
798 member type can be converted to an rvalue of type bool. */
799 if (ARITHMETIC_TYPE_P (from)
800 || fcode == ENUMERAL_TYPE
801 || fcode == POINTER_TYPE
802 || TYPE_PTR_TO_MEMBER_P (from))
804 conv = build_conv (ck_std, to, conv);
805 if (fcode == POINTER_TYPE
806 || TYPE_PTRMEM_P (from)
807 || (TYPE_PTRMEMFUNC_P (from)
808 && conv->rank < cr_pbool))
809 conv->rank = cr_pbool;
815 /* We don't check for ENUMERAL_TYPE here because there are no standard
816 conversions to enum type. */
817 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
818 || tcode == REAL_TYPE)
820 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
822 conv = build_conv (ck_std, to, conv);
824 /* Give this a better rank if it's a promotion. */
825 if (same_type_p (to, type_promotes_to (from))
826 && conv->u.next->rank <= cr_promotion)
827 conv->rank = cr_promotion;
829 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
830 && vector_types_convertible_p (from, to))
831 return build_conv (ck_std, to, conv);
832 else if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
833 && is_properly_derived_from (from, to))
835 if (conv->kind == ck_rvalue)
837 conv = build_conv (ck_base, to, conv);
838 /* The derived-to-base conversion indicates the initialization
839 of a parameter with base type from an object of a derived
840 type. A temporary object is created to hold the result of
842 conv->need_temporary_p = true;
850 /* Returns nonzero if T1 is reference-related to T2. */
853 reference_related_p (tree t1, tree t2)
855 t1 = TYPE_MAIN_VARIANT (t1);
856 t2 = TYPE_MAIN_VARIANT (t2);
860 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
861 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
863 return (same_type_p (t1, t2)
864 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
865 && DERIVED_FROM_P (t1, t2)));
868 /* Returns nonzero if T1 is reference-compatible with T2. */
871 reference_compatible_p (tree t1, tree t2)
875 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
876 reference-related to T2 and cv1 is the same cv-qualification as,
877 or greater cv-qualification than, cv2. */
878 return (reference_related_p (t1, t2)
879 && at_least_as_qualified_p (t1, t2));
882 /* Determine whether or not the EXPR (of class type S) can be
883 converted to T as in [over.match.ref]. */
886 convert_class_to_reference (tree t, tree s, tree expr)
892 struct z_candidate *candidates;
893 struct z_candidate *cand;
896 conversions = lookup_conversions (s);
902 Assuming that "cv1 T" is the underlying type of the reference
903 being initialized, and "cv S" is the type of the initializer
904 expression, with S a class type, the candidate functions are
907 --The conversion functions of S and its base classes are
908 considered. Those that are not hidden within S and yield type
909 "reference to cv2 T2", where "cv1 T" is reference-compatible
910 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
912 The argument list has one argument, which is the initializer
917 /* Conceptually, we should take the address of EXPR and put it in
918 the argument list. Unfortunately, however, that can result in
919 error messages, which we should not issue now because we are just
920 trying to find a conversion operator. Therefore, we use NULL,
921 cast to the appropriate type. */
922 arglist = build_int_cst (build_pointer_type (s), 0, 0);
923 arglist = build_tree_list (NULL_TREE, arglist);
925 reference_type = build_reference_type (t);
929 tree fns = TREE_VALUE (conversions);
931 for (; fns; fns = OVL_NEXT (fns))
933 tree f = OVL_CURRENT (fns);
934 tree t2 = TREE_TYPE (TREE_TYPE (f));
938 /* If this is a template function, try to get an exact
940 if (TREE_CODE (f) == TEMPLATE_DECL)
942 cand = add_template_candidate (&candidates,
948 TREE_PURPOSE (conversions),
954 /* Now, see if the conversion function really returns
955 an lvalue of the appropriate type. From the
956 point of view of unification, simply returning an
957 rvalue of the right type is good enough. */
959 t2 = TREE_TYPE (TREE_TYPE (f));
960 if (TREE_CODE (t2) != REFERENCE_TYPE
961 || !reference_compatible_p (t, TREE_TYPE (t2)))
963 candidates = candidates->next;
968 else if (TREE_CODE (t2) == REFERENCE_TYPE
969 && reference_compatible_p (t, TREE_TYPE (t2)))
970 cand = add_function_candidate (&candidates, f, s, arglist,
972 TREE_PURPOSE (conversions),
977 conversion *identity_conv;
978 /* Build a standard conversion sequence indicating the
979 binding from the reference type returned by the
980 function to the desired REFERENCE_TYPE. */
982 = build_identity_conv (TREE_TYPE (TREE_TYPE
983 (TREE_TYPE (cand->fn))),
986 = (direct_reference_binding
987 (reference_type, identity_conv));
988 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
991 conversions = TREE_CHAIN (conversions);
994 candidates = splice_viable (candidates, pedantic, &any_viable_p);
995 /* If none of the conversion functions worked out, let our caller
1000 cand = tourney (candidates);
1004 /* Now that we know that this is the function we're going to use fix
1005 the dummy first argument. */
1006 cand->args = tree_cons (NULL_TREE,
1008 TREE_CHAIN (cand->args));
1010 /* Build a user-defined conversion sequence representing the
1012 conv = build_conv (ck_user,
1013 TREE_TYPE (TREE_TYPE (cand->fn)),
1014 build_identity_conv (TREE_TYPE (expr), expr));
1017 /* Merge it with the standard conversion sequence from the
1018 conversion function's return type to the desired type. */
1019 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1021 if (cand->viable == -1)
1024 return cand->second_conv;
1027 /* A reference of the indicated TYPE is being bound directly to the
1028 expression represented by the implicit conversion sequence CONV.
1029 Return a conversion sequence for this binding. */
1032 direct_reference_binding (tree type, conversion *conv)
1036 my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 20030306);
1037 my_friendly_assert (TREE_CODE (conv->type) != REFERENCE_TYPE, 20030306);
1039 t = TREE_TYPE (type);
1043 When a parameter of reference type binds directly
1044 (_dcl.init.ref_) to an argument expression, the implicit
1045 conversion sequence is the identity conversion, unless the
1046 argument expression has a type that is a derived class of the
1047 parameter type, in which case the implicit conversion sequence is
1048 a derived-to-base Conversion.
1050 If the parameter binds directly to the result of applying a
1051 conversion function to the argument expression, the implicit
1052 conversion sequence is a user-defined conversion sequence
1053 (_over.ics.user_), with the second standard conversion sequence
1054 either an identity conversion or, if the conversion function
1055 returns an entity of a type that is a derived class of the
1056 parameter type, a derived-to-base conversion. */
1057 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1059 /* Represent the derived-to-base conversion. */
1060 conv = build_conv (ck_base, t, conv);
1061 /* We will actually be binding to the base-class subobject in
1062 the derived class, so we mark this conversion appropriately.
1063 That way, convert_like knows not to generate a temporary. */
1064 conv->need_temporary_p = false;
1066 return build_conv (ck_ref_bind, type, conv);
1069 /* Returns the conversion path from type FROM to reference type TO for
1070 purposes of reference binding. For lvalue binding, either pass a
1071 reference type to FROM or an lvalue expression to EXPR. If the
1072 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1073 the conversion returned. */
1076 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1078 conversion *conv = NULL;
1079 tree to = TREE_TYPE (rto);
1083 cp_lvalue_kind lvalue_p = clk_none;
1085 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1087 expr = instantiate_type (to, expr, tf_none);
1088 if (expr == error_mark_node)
1090 from = TREE_TYPE (expr);
1093 if (TREE_CODE (from) == REFERENCE_TYPE)
1095 /* Anything with reference type is an lvalue. */
1096 lvalue_p = clk_ordinary;
1097 from = TREE_TYPE (from);
1100 lvalue_p = real_lvalue_p (expr);
1102 /* Figure out whether or not the types are reference-related and
1103 reference compatible. We have do do this after stripping
1104 references from FROM. */
1105 related_p = reference_related_p (to, from);
1106 compatible_p = reference_compatible_p (to, from);
1108 if (lvalue_p && compatible_p)
1112 If the initializer expression
1114 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1115 is reference-compatible with "cv2 T2,"
1117 the reference is bound directly to the initializer expression
1119 conv = build_identity_conv (from, expr);
1120 conv = direct_reference_binding (rto, conv);
1121 if ((lvalue_p & clk_bitfield) != 0
1122 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1123 /* For the purposes of overload resolution, we ignore the fact
1124 this expression is a bitfield or packed field. (In particular,
1125 [over.ics.ref] says specifically that a function with a
1126 non-const reference parameter is viable even if the
1127 argument is a bitfield.)
1129 However, when we actually call the function we must create
1130 a temporary to which to bind the reference. If the
1131 reference is volatile, or isn't const, then we cannot make
1132 a temporary, so we just issue an error when the conversion
1134 conv->need_temporary_p = true;
1138 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1142 If the initializer expression
1144 -- has a class type (i.e., T2 is a class type) can be
1145 implicitly converted to an lvalue of type "cv3 T3," where
1146 "cv1 T1" is reference-compatible with "cv3 T3". (this
1147 conversion is selected by enumerating the applicable
1148 conversion functions (_over.match.ref_) and choosing the
1149 best one through overload resolution. (_over.match_).
1151 the reference is bound to the lvalue result of the conversion
1152 in the second case. */
1153 conv = convert_class_to_reference (to, from, expr);
1158 /* From this point on, we conceptually need temporaries, even if we
1159 elide them. Only the cases above are "direct bindings". */
1160 if (flags & LOOKUP_NO_TEMP_BIND)
1165 When a parameter of reference type is not bound directly to an
1166 argument expression, the conversion sequence is the one required
1167 to convert the argument expression to the underlying type of the
1168 reference according to _over.best.ics_. Conceptually, this
1169 conversion sequence corresponds to copy-initializing a temporary
1170 of the underlying type with the argument expression. Any
1171 difference in top-level cv-qualification is subsumed by the
1172 initialization itself and does not constitute a conversion. */
1176 Otherwise, the reference shall be to a non-volatile const type. */
1177 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1182 If the initializer expression is an rvalue, with T2 a class type,
1183 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1184 is bound in one of the following ways:
1186 -- The reference is bound to the object represented by the rvalue
1187 or to a sub-object within that object.
1191 We use the first alternative. The implicit conversion sequence
1192 is supposed to be same as we would obtain by generating a
1193 temporary. Fortunately, if the types are reference compatible,
1194 then this is either an identity conversion or the derived-to-base
1195 conversion, just as for direct binding. */
1196 if (CLASS_TYPE_P (from) && compatible_p)
1198 conv = build_identity_conv (from, expr);
1199 conv = direct_reference_binding (rto, conv);
1200 if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
1201 conv->u.next->check_copy_constructor_p = true;
1207 Otherwise, a temporary of type "cv1 T1" is created and
1208 initialized from the initializer expression using the rules for a
1209 non-reference copy initialization. If T1 is reference-related to
1210 T2, cv1 must be the same cv-qualification as, or greater
1211 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1212 if (related_p && !at_least_as_qualified_p (to, from))
1215 conv = implicit_conversion (to, from, expr, flags);
1219 conv = build_conv (ck_ref_bind, rto, conv);
1220 /* This reference binding, unlike those above, requires the
1221 creation of a temporary. */
1222 conv->need_temporary_p = true;
1227 /* Returns the implicit conversion sequence (see [over.ics]) from type FROM
1228 to type TO. The optional expression EXPR may affect the conversion.
1229 FLAGS are the usual overloading flags. Only LOOKUP_NO_CONVERSION is
1233 implicit_conversion (tree to, tree from, tree expr, int flags)
1237 if (from == error_mark_node || to == error_mark_node
1238 || expr == error_mark_node)
1241 if (TREE_CODE (to) == REFERENCE_TYPE)
1242 conv = reference_binding (to, from, expr, flags);
1244 conv = standard_conversion (to, from, expr);
1249 if (expr != NULL_TREE
1250 && (IS_AGGR_TYPE (from)
1251 || IS_AGGR_TYPE (to))
1252 && (flags & LOOKUP_NO_CONVERSION) == 0)
1254 struct z_candidate *cand;
1256 cand = build_user_type_conversion_1
1257 (to, expr, LOOKUP_ONLYCONVERTING);
1259 conv = cand->second_conv;
1261 /* We used to try to bind a reference to a temporary here, but that
1262 is now handled by the recursive call to this function at the end
1263 of reference_binding. */
1270 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1273 static struct z_candidate *
1274 add_candidate (struct z_candidate **candidates,
1276 size_t num_convs, conversion **convs,
1277 tree access_path, tree conversion_path,
1280 struct z_candidate *cand
1281 = conversion_obstack_alloc (sizeof (struct z_candidate));
1285 cand->convs = convs;
1286 cand->num_convs = num_convs;
1287 cand->access_path = access_path;
1288 cand->conversion_path = conversion_path;
1289 cand->viable = viable;
1290 cand->next = *candidates;
1296 /* Create an overload candidate for the function or method FN called with
1297 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1298 to implicit_conversion.
1300 CTYPE, if non-NULL, is the type we want to pretend this function
1301 comes from for purposes of overload resolution. */
1303 static struct z_candidate *
1304 add_function_candidate (struct z_candidate **candidates,
1305 tree fn, tree ctype, tree arglist,
1306 tree access_path, tree conversion_path,
1309 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1312 tree parmnode, argnode;
1316 /* Built-in functions that haven't been declared don't really
1318 if (DECL_ANTICIPATED (fn))
1321 /* The `this', `in_chrg' and VTT arguments to constructors are not
1322 considered in overload resolution. */
1323 if (DECL_CONSTRUCTOR_P (fn))
1325 parmlist = skip_artificial_parms_for (fn, parmlist);
1326 orig_arglist = arglist;
1327 arglist = skip_artificial_parms_for (fn, arglist);
1330 orig_arglist = arglist;
1332 len = list_length (arglist);
1333 convs = alloc_conversions (len);
1335 /* 13.3.2 - Viable functions [over.match.viable]
1336 First, to be a viable function, a candidate function shall have enough
1337 parameters to agree in number with the arguments in the list.
1339 We need to check this first; otherwise, checking the ICSes might cause
1340 us to produce an ill-formed template instantiation. */
1342 parmnode = parmlist;
1343 for (i = 0; i < len; ++i)
1345 if (parmnode == NULL_TREE || parmnode == void_list_node)
1347 parmnode = TREE_CHAIN (parmnode);
1350 if (i < len && parmnode)
1353 /* Make sure there are default args for the rest of the parms. */
1354 else if (!sufficient_parms_p (parmnode))
1360 /* Second, for F to be a viable function, there shall exist for each
1361 argument an implicit conversion sequence that converts that argument
1362 to the corresponding parameter of F. */
1364 parmnode = parmlist;
1367 for (i = 0; i < len; ++i)
1369 tree arg = TREE_VALUE (argnode);
1370 tree argtype = lvalue_type (arg);
1374 if (parmnode == void_list_node)
1377 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1378 && ! DECL_CONSTRUCTOR_P (fn));
1382 tree parmtype = TREE_VALUE (parmnode);
1384 /* The type of the implicit object parameter ('this') for
1385 overload resolution is not always the same as for the
1386 function itself; conversion functions are considered to
1387 be members of the class being converted, and functions
1388 introduced by a using-declaration are considered to be
1389 members of the class that uses them.
1391 Since build_over_call ignores the ICS for the `this'
1392 parameter, we can just change the parm type. */
1393 if (ctype && is_this)
1396 = build_qualified_type (ctype,
1397 TYPE_QUALS (TREE_TYPE (parmtype)));
1398 parmtype = build_pointer_type (parmtype);
1401 t = implicit_conversion (parmtype, argtype, arg, flags);
1405 t = build_identity_conv (argtype, arg);
1406 t->ellipsis_p = true;
1423 parmnode = TREE_CHAIN (parmnode);
1424 argnode = TREE_CHAIN (argnode);
1428 return add_candidate (candidates, fn, orig_arglist, len, convs,
1429 access_path, conversion_path, viable);
1432 /* Create an overload candidate for the conversion function FN which will
1433 be invoked for expression OBJ, producing a pointer-to-function which
1434 will in turn be called with the argument list ARGLIST, and add it to
1435 CANDIDATES. FLAGS is passed on to implicit_conversion.
1437 Actually, we don't really care about FN; we care about the type it
1438 converts to. There may be multiple conversion functions that will
1439 convert to that type, and we rely on build_user_type_conversion_1 to
1440 choose the best one; so when we create our candidate, we record the type
1441 instead of the function. */
1443 static struct z_candidate *
1444 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1445 tree arglist, tree access_path, tree conversion_path)
1447 tree totype = TREE_TYPE (TREE_TYPE (fn));
1448 int i, len, viable, flags;
1449 tree parmlist, parmnode, argnode;
1452 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1453 parmlist = TREE_TYPE (parmlist);
1454 parmlist = TYPE_ARG_TYPES (parmlist);
1456 len = list_length (arglist) + 1;
1457 convs = alloc_conversions (len);
1458 parmnode = parmlist;
1461 flags = LOOKUP_NORMAL;
1463 /* Don't bother looking up the same type twice. */
1464 if (*candidates && (*candidates)->fn == totype)
1467 for (i = 0; i < len; ++i)
1469 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1470 tree argtype = lvalue_type (arg);
1474 t = implicit_conversion (totype, argtype, arg, flags);
1475 else if (parmnode == void_list_node)
1478 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, flags);
1481 t = build_identity_conv (argtype, arg);
1482 t->ellipsis_p = true;
1496 parmnode = TREE_CHAIN (parmnode);
1497 argnode = TREE_CHAIN (argnode);
1503 if (!sufficient_parms_p (parmnode))
1506 return add_candidate (candidates, totype, arglist, len, convs,
1507 access_path, conversion_path, viable);
1511 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1512 tree type1, tree type2, tree *args, tree *argtypes,
1524 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1525 convs = alloc_conversions (num_convs);
1527 for (i = 0; i < 2; ++i)
1532 t = implicit_conversion (types[i], argtypes[i], args[i], flags);
1536 /* We need something for printing the candidate. */
1537 t = build_identity_conv (types[i], NULL_TREE);
1544 /* For COND_EXPR we rearranged the arguments; undo that now. */
1547 convs[2] = convs[1];
1548 convs[1] = convs[0];
1549 t = implicit_conversion (boolean_type_node, argtypes[2], args[2], 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 CONVERT_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 (TREE_TYPE (TREE_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 && TYPE_USES_VIRTUAL_BASECLASSES (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, -1);
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)
2351 build_this (tree obj)
2353 /* Fix this to work on non-lvalues. */
2354 return build_unary_op (ADDR_EXPR, obj, 0);
2357 /* Returns true iff functions are equivalent. Equivalent functions are
2358 not '==' only if one is a function-local extern function or if
2359 both are extern "C". */
2362 equal_functions (tree fn1, tree fn2)
2364 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2365 || DECL_EXTERN_C_FUNCTION_P (fn1))
2366 return decls_match (fn1, fn2);
2370 /* Print information about one overload candidate CANDIDATE. MSGSTR
2371 is the text to print before the candidate itself.
2373 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2374 to have been run through gettext by the caller. This wart makes
2375 life simpler in print_z_candidates and for the translators. */
2378 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2380 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2382 if (candidate->num_convs == 3)
2383 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2384 candidate->convs[0]->type,
2385 candidate->convs[1]->type,
2386 candidate->convs[2]->type);
2387 else if (candidate->num_convs == 2)
2388 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2389 candidate->convs[0]->type,
2390 candidate->convs[1]->type);
2392 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2393 candidate->convs[0]->type);
2395 else if (TYPE_P (candidate->fn))
2396 inform ("%s %T <conversion>", msgstr, candidate->fn);
2397 else if (candidate->viable == -1)
2398 inform ("%J%s %+#D <near match>", candidate->fn, msgstr, candidate->fn);
2400 inform ("%J%s %+#D", candidate->fn, msgstr, candidate->fn);
2404 print_z_candidates (struct z_candidate *candidates)
2407 struct z_candidate *cand1;
2408 struct z_candidate **cand2;
2410 /* There may be duplicates in the set of candidates. We put off
2411 checking this condition as long as possible, since we have no way
2412 to eliminate duplicates from a set of functions in less than n^2
2413 time. Now we are about to emit an error message, so it is more
2414 permissible to go slowly. */
2415 for (cand1 = candidates; cand1; cand1 = cand1->next)
2417 tree fn = cand1->fn;
2418 /* Skip builtin candidates and conversion functions. */
2419 if (TREE_CODE (fn) != FUNCTION_DECL)
2421 cand2 = &cand1->next;
2424 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2425 && equal_functions (fn, (*cand2)->fn))
2426 *cand2 = (*cand2)->next;
2428 cand2 = &(*cand2)->next;
2435 str = _("candidates are:");
2436 print_z_candidate (str, candidates);
2437 if (candidates->next)
2439 /* Indent successive candidates by the width of the translation
2440 of the above string. */
2441 size_t len = gcc_gettext_width (str) + 1;
2442 char *spaces = alloca (len);
2443 memset (spaces, ' ', len-1);
2444 spaces[len - 1] = '\0';
2446 candidates = candidates->next;
2449 print_z_candidate (spaces, candidates);
2450 candidates = candidates->next;
2456 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2457 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2458 the result of the conversion function to convert it to the final
2459 desired type. Merge the the two sequences into a single sequence,
2460 and return the merged sequence. */
2463 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2467 my_friendly_assert (user_seq->kind == ck_user, 20030306);
2469 /* Find the end of the second conversion sequence. */
2471 while ((*t)->kind != ck_identity)
2472 t = &((*t)->u.next);
2474 /* Replace the identity conversion with the user conversion
2478 /* The entire sequence is a user-conversion sequence. */
2479 std_seq->user_conv_p = true;
2484 /* Returns the best overload candidate to perform the requested
2485 conversion. This function is used for three the overloading situations
2486 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2487 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2488 per [dcl.init.ref], so we ignore temporary bindings. */
2490 static struct z_candidate *
2491 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2493 struct z_candidate *candidates, *cand;
2494 tree fromtype = TREE_TYPE (expr);
2495 tree ctors = NULL_TREE;
2496 tree conv_fns = NULL_TREE;
2497 conversion *conv = NULL;
2498 tree args = NULL_TREE;
2501 /* We represent conversion within a hierarchy using RVALUE_CONV and
2502 BASE_CONV, as specified by [over.best.ics]; these become plain
2503 constructor calls, as specified in [dcl.init]. */
2504 my_friendly_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2505 || !DERIVED_FROM_P (totype, fromtype), 20011226);
2507 if (IS_AGGR_TYPE (totype))
2508 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2510 if (IS_AGGR_TYPE (fromtype))
2511 conv_fns = lookup_conversions (fromtype);
2514 flags |= LOOKUP_NO_CONVERSION;
2520 ctors = BASELINK_FUNCTIONS (ctors);
2522 t = build_int_cst (build_pointer_type (totype), 0, 0);
2523 args = build_tree_list (NULL_TREE, expr);
2524 /* We should never try to call the abstract or base constructor
2526 my_friendly_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2527 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)),
2529 args = tree_cons (NULL_TREE, t, args);
2531 for (; ctors; ctors = OVL_NEXT (ctors))
2533 tree ctor = OVL_CURRENT (ctors);
2534 if (DECL_NONCONVERTING_P (ctor))
2537 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2538 cand = add_template_candidate (&candidates, ctor, totype,
2539 NULL_TREE, args, NULL_TREE,
2540 TYPE_BINFO (totype),
2541 TYPE_BINFO (totype),
2545 cand = add_function_candidate (&candidates, ctor, totype,
2546 args, TYPE_BINFO (totype),
2547 TYPE_BINFO (totype),
2551 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2555 args = build_tree_list (NULL_TREE, build_this (expr));
2557 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2560 tree conversion_path = TREE_PURPOSE (conv_fns);
2561 int convflags = LOOKUP_NO_CONVERSION;
2563 /* If we are called to convert to a reference type, we are trying to
2564 find an lvalue binding, so don't even consider temporaries. If
2565 we don't find an lvalue binding, the caller will try again to
2566 look for a temporary binding. */
2567 if (TREE_CODE (totype) == REFERENCE_TYPE)
2568 convflags |= LOOKUP_NO_TEMP_BIND;
2570 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2572 tree fn = OVL_CURRENT (fns);
2574 /* [over.match.funcs] For conversion functions, the function
2575 is considered to be a member of the class of the implicit
2576 object argument for the purpose of defining the type of
2577 the implicit object parameter.
2579 So we pass fromtype as CTYPE to add_*_candidate. */
2581 if (TREE_CODE (fn) == TEMPLATE_DECL)
2582 cand = add_template_candidate (&candidates, fn, fromtype,
2585 TYPE_BINFO (fromtype),
2590 cand = add_function_candidate (&candidates, fn, fromtype,
2592 TYPE_BINFO (fromtype),
2599 = implicit_conversion (totype,
2600 TREE_TYPE (TREE_TYPE (cand->fn)),
2603 cand->second_conv = ics;
2607 else if (candidates->viable == 1 && ics->bad_p)
2613 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2617 cand = tourney (candidates);
2620 if (flags & LOOKUP_COMPLAIN)
2622 error ("conversion from `%T' to `%T' is ambiguous",
2624 print_z_candidates (candidates);
2627 cand = candidates; /* any one will do */
2628 cand->second_conv = build_ambiguous_conv (totype, expr);
2629 cand->second_conv->user_conv_p = true;
2630 if (!any_strictly_viable (candidates))
2631 cand->second_conv->bad_p = true;
2632 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2633 ambiguous conversion is no worse than another user-defined
2639 /* Build the user conversion sequence. */
2642 (DECL_CONSTRUCTOR_P (cand->fn)
2643 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2644 build_identity_conv (TREE_TYPE (expr), expr));
2647 /* Combine it with the second conversion sequence. */
2648 cand->second_conv = merge_conversion_sequences (conv,
2651 if (cand->viable == -1)
2652 cand->second_conv->bad_p = true;
2658 build_user_type_conversion (tree totype, tree expr, int flags)
2660 struct z_candidate *cand
2661 = build_user_type_conversion_1 (totype, expr, flags);
2665 if (cand->second_conv->kind == ck_ambig)
2666 return error_mark_node;
2667 return convert_from_reference (convert_like (cand->second_conv, expr));
2672 /* Do any initial processing on the arguments to a function call. */
2675 resolve_args (tree args)
2678 for (t = args; t; t = TREE_CHAIN (t))
2680 tree arg = TREE_VALUE (t);
2682 if (arg == error_mark_node)
2683 return error_mark_node;
2684 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2686 error ("invalid use of void expression");
2687 return error_mark_node;
2689 arg = convert_from_reference (arg);
2690 TREE_VALUE (t) = arg;
2695 /* Perform overload resolution on FN, which is called with the ARGS.
2697 Return the candidate function selected by overload resolution, or
2698 NULL if the event that overload resolution failed. In the case
2699 that overload resolution fails, *CANDIDATES will be the set of
2700 candidates considered, and ANY_VIABLE_P will be set to true or
2701 false to indicate whether or not any of the candidates were
2704 The ARGS should already have gone through RESOLVE_ARGS before this
2705 function is called. */
2707 static struct z_candidate *
2708 perform_overload_resolution (tree fn,
2710 struct z_candidate **candidates,
2713 struct z_candidate *cand;
2714 tree explicit_targs = NULL_TREE;
2715 int template_only = 0;
2718 *any_viable_p = true;
2720 /* Check FN and ARGS. */
2721 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
2722 || TREE_CODE (fn) == TEMPLATE_DECL
2723 || TREE_CODE (fn) == OVERLOAD
2724 || TREE_CODE (fn) == TEMPLATE_ID_EXPR,
2726 my_friendly_assert (!args || TREE_CODE (args) == TREE_LIST,
2729 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2731 explicit_targs = TREE_OPERAND (fn, 1);
2732 fn = TREE_OPERAND (fn, 0);
2736 /* Add the various candidate functions. */
2737 add_candidates (fn, args, explicit_targs, template_only,
2738 /*conversion_path=*/NULL_TREE,
2739 /*access_path=*/NULL_TREE,
2743 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2747 cand = tourney (*candidates);
2751 /* Return an expression for a call to FN (a namespace-scope function,
2752 or a static member function) with the ARGS. */
2755 build_new_function_call (tree fn, tree args)
2757 struct z_candidate *candidates, *cand;
2762 args = resolve_args (args);
2763 if (args == error_mark_node)
2764 return error_mark_node;
2766 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2767 p = conversion_obstack_alloc (0);
2769 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2773 if (!any_viable_p && candidates && ! candidates->next)
2774 return build_function_call (candidates->fn, args);
2775 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2776 fn = TREE_OPERAND (fn, 0);
2778 error ("no matching function for call to `%D(%A)'",
2779 DECL_NAME (OVL_CURRENT (fn)), args);
2781 error ("call of overloaded `%D(%A)' is ambiguous",
2782 DECL_NAME (OVL_CURRENT (fn)), args);
2784 print_z_candidates (candidates);
2785 result = error_mark_node;
2788 result = build_over_call (cand, LOOKUP_NORMAL);
2790 /* Free all the conversions we allocated. */
2791 obstack_free (&conversion_obstack, p);
2796 /* Build a call to a global operator new. FNNAME is the name of the
2797 operator (either "operator new" or "operator new[]") and ARGS are
2798 the arguments provided. *SIZE points to the total number of bytes
2799 required by the allocation, and is updated if that is changed here.
2800 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2801 function determines that no cookie should be used, after all,
2802 *COOKIE_SIZE is set to NULL_TREE. */
2805 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2808 struct z_candidate *candidates;
2809 struct z_candidate *cand;
2812 args = tree_cons (NULL_TREE, *size, args);
2813 args = resolve_args (args);
2814 if (args == error_mark_node)
2821 If this lookup fails to find the name, or if the allocated type
2822 is not a class type, the allocation function's name is looked
2823 up in the global scope.
2825 we disregard block-scope declarations of "operator new". */
2826 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
2828 /* Figure out what function is being called. */
2829 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2831 /* If no suitable function could be found, issue an error message
2836 error ("no matching function for call to `%D(%A)'",
2837 DECL_NAME (OVL_CURRENT (fns)), args);
2839 error ("call of overloaded `%D(%A)' is ambiguous",
2840 DECL_NAME (OVL_CURRENT (fns)), args);
2842 print_z_candidates (candidates);
2843 return error_mark_node;
2846 /* If a cookie is required, add some extra space. Whether
2847 or not a cookie is required cannot be determined until
2848 after we know which function was called. */
2851 bool use_cookie = true;
2852 if (!abi_version_at_least (2))
2854 tree placement = TREE_CHAIN (args);
2855 /* In G++ 3.2, the check was implemented incorrectly; it
2856 looked at the placement expression, rather than the
2857 type of the function. */
2858 if (placement && !TREE_CHAIN (placement)
2859 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2867 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2868 /* Skip the size_t parameter. */
2869 arg_types = TREE_CHAIN (arg_types);
2870 /* Check the remaining parameters (if any). */
2872 && TREE_CHAIN (arg_types) == void_list_node
2873 && same_type_p (TREE_VALUE (arg_types),
2877 /* If we need a cookie, adjust the number of bytes allocated. */
2880 /* Update the total size. */
2881 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2882 /* Update the argument list to reflect the adjusted size. */
2883 TREE_VALUE (args) = *size;
2886 *cookie_size = NULL_TREE;
2889 /* Build the CALL_EXPR. */
2890 return build_over_call (cand, LOOKUP_NORMAL);
2894 build_object_call (tree obj, tree args)
2896 struct z_candidate *candidates = 0, *cand;
2897 tree fns, convs, mem_args = NULL_TREE;
2898 tree type = TREE_TYPE (obj);
2900 tree result = NULL_TREE;
2903 if (TYPE_PTRMEMFUNC_P (type))
2905 /* It's no good looking for an overloaded operator() on a
2906 pointer-to-member-function. */
2907 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2908 return error_mark_node;
2911 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2912 if (fns == error_mark_node)
2913 return error_mark_node;
2915 args = resolve_args (args);
2917 if (args == error_mark_node)
2918 return error_mark_node;
2920 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2921 p = conversion_obstack_alloc (0);
2925 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2926 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2928 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2930 tree fn = OVL_CURRENT (fns);
2931 if (TREE_CODE (fn) == TEMPLATE_DECL)
2932 add_template_candidate (&candidates, fn, base, NULL_TREE,
2933 mem_args, NULL_TREE,
2936 LOOKUP_NORMAL, DEDUCE_CALL);
2938 add_function_candidate
2939 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2940 TYPE_BINFO (type), LOOKUP_NORMAL);
2944 convs = lookup_conversions (type);
2946 for (; convs; convs = TREE_CHAIN (convs))
2948 tree fns = TREE_VALUE (convs);
2949 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2951 if ((TREE_CODE (totype) == POINTER_TYPE
2952 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2953 || (TREE_CODE (totype) == REFERENCE_TYPE
2954 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2955 || (TREE_CODE (totype) == REFERENCE_TYPE
2956 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2957 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2958 for (; fns; fns = OVL_NEXT (fns))
2960 tree fn = OVL_CURRENT (fns);
2961 if (TREE_CODE (fn) == TEMPLATE_DECL)
2962 add_template_conv_candidate
2963 (&candidates, fn, obj, args, totype,
2964 /*access_path=*/NULL_TREE,
2965 /*conversion_path=*/NULL_TREE);
2967 add_conv_candidate (&candidates, fn, obj, args,
2968 /*conversion_path=*/NULL_TREE,
2969 /*access_path=*/NULL_TREE);
2973 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2976 error ("no match for call to `(%T) (%A)'", TREE_TYPE (obj), args);
2977 print_z_candidates (candidates);
2978 result = error_mark_node;
2982 cand = tourney (candidates);
2985 error ("call of `(%T) (%A)' is ambiguous", TREE_TYPE (obj), args);
2986 print_z_candidates (candidates);
2987 result = error_mark_node;
2989 /* Since cand->fn will be a type, not a function, for a conversion
2990 function, we must be careful not to unconditionally look at
2992 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
2993 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
2994 result = build_over_call (cand, LOOKUP_NORMAL);
2997 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1);
2998 result = build_function_call (obj, args);
3002 /* Free all the conversions we allocated. */
3003 obstack_free (&conversion_obstack, p);
3009 op_error (enum tree_code code, enum tree_code code2,
3010 tree arg1, tree arg2, tree arg3, const char *problem)
3014 if (code == MODIFY_EXPR)
3015 opname = assignment_operator_name_info[code2].name;
3017 opname = operator_name_info[code].name;
3022 error ("%s for ternary 'operator?:' in '%E ? %E : %E'",
3023 problem, arg1, arg2, arg3);
3026 case POSTINCREMENT_EXPR:
3027 case POSTDECREMENT_EXPR:
3028 error ("%s for 'operator%s' in '%E%s'", problem, opname, arg1, opname);
3032 error ("%s for 'operator[]' in '%E[%E]'", problem, arg1, arg2);
3037 error ("%s for '%s' in '%s %E'", problem, opname, opname, arg1);
3042 error ("%s for 'operator%s' in '%E %s %E'",
3043 problem, opname, arg1, opname, arg2);
3045 error ("%s for 'operator%s' in '%s%E'",
3046 problem, opname, opname, arg1);
3051 /* Return the implicit conversion sequence that could be used to
3052 convert E1 to E2 in [expr.cond]. */
3055 conditional_conversion (tree e1, tree e2)
3057 tree t1 = non_reference (TREE_TYPE (e1));
3058 tree t2 = non_reference (TREE_TYPE (e2));
3064 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3065 implicitly converted (clause _conv_) to the type "reference to
3066 T2", subject to the constraint that in the conversion the
3067 reference must bind directly (_dcl.init.ref_) to E1. */
3068 if (real_lvalue_p (e2))
3070 conv = implicit_conversion (build_reference_type (t2),
3073 LOOKUP_NO_TEMP_BIND);
3080 If E1 and E2 have class type, and the underlying class types are
3081 the same or one is a base class of the other: E1 can be converted
3082 to match E2 if the class of T2 is the same type as, or a base
3083 class of, the class of T1, and the cv-qualification of T2 is the
3084 same cv-qualification as, or a greater cv-qualification than, the
3085 cv-qualification of T1. If the conversion is applied, E1 is
3086 changed to an rvalue of type T2 that still refers to the original
3087 source class object (or the appropriate subobject thereof). */
3088 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3089 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3091 if (good_base && at_least_as_qualified_p (t2, t1))
3093 conv = build_identity_conv (t1, e1);
3094 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3095 TYPE_MAIN_VARIANT (t2)))
3096 conv = build_conv (ck_base, t2, conv);
3098 conv = build_conv (ck_rvalue, t2, conv);
3107 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3108 converted to the type that expression E2 would have if E2 were
3109 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3110 return implicit_conversion (t2, t1, e1, LOOKUP_NORMAL);
3113 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3114 arguments to the conditional expression. */
3117 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3121 tree result = NULL_TREE;
3122 tree result_type = NULL_TREE;
3123 bool lvalue_p = true;
3124 struct z_candidate *candidates = 0;
3125 struct z_candidate *cand;
3128 /* As a G++ extension, the second argument to the conditional can be
3129 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3130 c'.) If the second operand is omitted, make sure it is
3131 calculated only once. */
3135 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3137 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3138 if (real_lvalue_p (arg1))
3139 arg2 = arg1 = stabilize_reference (arg1);
3141 arg2 = arg1 = save_expr (arg1);
3146 The first expr ession is implicitly converted to bool (clause
3148 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3150 /* If something has already gone wrong, just pass that fact up the
3152 if (error_operand_p (arg1)
3153 || error_operand_p (arg2)
3154 || error_operand_p (arg3))
3155 return error_mark_node;
3159 If either the second or the third operand has type (possibly
3160 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3161 array-to-pointer (_conv.array_), and function-to-pointer
3162 (_conv.func_) standard conversions are performed on the second
3163 and third operands. */
3164 arg2_type = TREE_TYPE (arg2);
3165 arg3_type = TREE_TYPE (arg3);
3166 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3168 /* Do the conversions. We don't these for `void' type arguments
3169 since it can't have any effect and since decay_conversion
3170 does not handle that case gracefully. */
3171 if (!VOID_TYPE_P (arg2_type))
3172 arg2 = decay_conversion (arg2);
3173 if (!VOID_TYPE_P (arg3_type))
3174 arg3 = decay_conversion (arg3);
3175 arg2_type = TREE_TYPE (arg2);
3176 arg3_type = TREE_TYPE (arg3);
3180 One of the following shall hold:
3182 --The second or the third operand (but not both) is a
3183 throw-expression (_except.throw_); the result is of the
3184 type of the other and is an rvalue.
3186 --Both the second and the third operands have type void; the
3187 result is of type void and is an rvalue.
3189 We must avoid calling force_rvalue for expressions of type
3190 "void" because it will complain that their value is being
3192 if (TREE_CODE (arg2) == THROW_EXPR
3193 && TREE_CODE (arg3) != THROW_EXPR)
3195 if (!VOID_TYPE_P (arg3_type))
3196 arg3 = force_rvalue (arg3);
3197 arg3_type = TREE_TYPE (arg3);
3198 result_type = arg3_type;
3200 else if (TREE_CODE (arg2) != THROW_EXPR
3201 && TREE_CODE (arg3) == THROW_EXPR)
3203 if (!VOID_TYPE_P (arg2_type))
3204 arg2 = force_rvalue (arg2);
3205 arg2_type = TREE_TYPE (arg2);
3206 result_type = arg2_type;
3208 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3209 result_type = void_type_node;
3212 error ("`%E' has type `void' and is not a throw-expression",
3213 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3214 return error_mark_node;
3218 goto valid_operands;
3222 Otherwise, if the second and third operand have different types,
3223 and either has (possibly cv-qualified) class type, an attempt is
3224 made to convert each of those operands to the type of the other. */
3225 else if (!same_type_p (arg2_type, arg3_type)
3226 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3231 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3232 p = conversion_obstack_alloc (0);
3234 conv2 = conditional_conversion (arg2, arg3);
3235 conv3 = conditional_conversion (arg3, arg2);
3239 If both can be converted, or one can be converted but the
3240 conversion is ambiguous, the program is ill-formed. If
3241 neither can be converted, the operands are left unchanged and
3242 further checking is performed as described below. If exactly
3243 one conversion is possible, that conversion is applied to the
3244 chosen operand and the converted operand is used in place of
3245 the original operand for the remainder of this section. */
3246 if ((conv2 && !conv2->bad_p
3247 && conv3 && !conv3->bad_p)
3248 || (conv2 && conv2->kind == ck_ambig)
3249 || (conv3 && conv3->kind == ck_ambig))
3251 error ("operands to ?: have different types");
3252 result = error_mark_node;
3254 else if (conv2 && !conv2->bad_p)
3256 arg2 = convert_like (conv2, arg2);
3257 arg2 = convert_from_reference (arg2);
3258 arg2_type = TREE_TYPE (arg2);
3260 else if (conv3 && !conv3->bad_p)
3262 arg3 = convert_like (conv3, arg3);
3263 arg3 = convert_from_reference (arg3);
3264 arg3_type = TREE_TYPE (arg3);
3267 /* Free all the conversions we allocated. */
3268 obstack_free (&conversion_obstack, p);
3273 /* If, after the conversion, both operands have class type,
3274 treat the cv-qualification of both operands as if it were the
3275 union of the cv-qualification of the operands.
3277 The standard is not clear about what to do in this
3278 circumstance. For example, if the first operand has type
3279 "const X" and the second operand has a user-defined
3280 conversion to "volatile X", what is the type of the second
3281 operand after this step? Making it be "const X" (matching
3282 the first operand) seems wrong, as that discards the
3283 qualification without actually performing a copy. Leaving it
3284 as "volatile X" seems wrong as that will result in the
3285 conditional expression failing altogether, even though,
3286 according to this step, the one operand could be converted to
3287 the type of the other. */
3288 if ((conv2 || conv3)
3289 && CLASS_TYPE_P (arg2_type)
3290 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3291 arg2_type = arg3_type =
3292 cp_build_qualified_type (arg2_type,
3293 TYPE_QUALS (arg2_type)
3294 | TYPE_QUALS (arg3_type));
3299 If the second and third operands are lvalues and have the same
3300 type, the result is of that type and is an lvalue. */
3301 if (real_lvalue_p (arg2)
3302 && real_lvalue_p (arg3)
3303 && same_type_p (arg2_type, arg3_type))
3305 result_type = arg2_type;
3306 goto valid_operands;
3311 Otherwise, the result is an rvalue. If the second and third
3312 operand do not have the same type, and either has (possibly
3313 cv-qualified) class type, overload resolution is used to
3314 determine the conversions (if any) to be applied to the operands
3315 (_over.match.oper_, _over.built_). */
3317 if (!same_type_p (arg2_type, arg3_type)
3318 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3324 /* Rearrange the arguments so that add_builtin_candidate only has
3325 to know about two args. In build_builtin_candidates, the
3326 arguments are unscrambled. */
3330 add_builtin_candidates (&candidates,
3333 ansi_opname (COND_EXPR),
3339 If the overload resolution fails, the program is
3341 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3344 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3345 print_z_candidates (candidates);
3346 return error_mark_node;
3348 cand = tourney (candidates);
3351 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3352 print_z_candidates (candidates);
3353 return error_mark_node;
3358 Otherwise, the conversions thus determined are applied, and
3359 the converted operands are used in place of the original
3360 operands for the remainder of this section. */
3361 conv = cand->convs[0];
3362 arg1 = convert_like (conv, arg1);
3363 conv = cand->convs[1];
3364 arg2 = convert_like (conv, arg2);
3365 conv = cand->convs[2];
3366 arg3 = convert_like (conv, arg3);
3371 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3372 and function-to-pointer (_conv.func_) standard conversions are
3373 performed on the second and third operands.
3375 We need to force the lvalue-to-rvalue conversion here for class types,
3376 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3377 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3380 arg2 = force_rvalue (arg2);
3381 if (!CLASS_TYPE_P (arg2_type))
3382 arg2_type = TREE_TYPE (arg2);
3384 arg3 = force_rvalue (arg3);
3385 if (!CLASS_TYPE_P (arg2_type))
3386 arg3_type = TREE_TYPE (arg3);
3388 if (arg2 == error_mark_node || arg3 == error_mark_node)
3389 return error_mark_node;
3393 After those conversions, one of the following shall hold:
3395 --The second and third operands have the same type; the result is of
3397 if (same_type_p (arg2_type, arg3_type))
3398 result_type = arg2_type;
3401 --The second and third operands have arithmetic or enumeration
3402 type; the usual arithmetic conversions are performed to bring
3403 them to a common type, and the result is of that type. */
3404 else if ((ARITHMETIC_TYPE_P (arg2_type)
3405 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3406 && (ARITHMETIC_TYPE_P (arg3_type)
3407 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3409 /* In this case, there is always a common type. */
3410 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3413 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3414 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3415 warning ("enumeral mismatch in conditional expression: `%T' vs `%T'",
3416 arg2_type, arg3_type);
3417 else if (extra_warnings
3418 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3419 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3420 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3421 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3422 warning ("enumeral and non-enumeral type in conditional expression");
3424 arg2 = perform_implicit_conversion (result_type, arg2);
3425 arg3 = perform_implicit_conversion (result_type, arg3);
3429 --The second and third operands have pointer type, or one has
3430 pointer type and the other is a null pointer constant; pointer
3431 conversions (_conv.ptr_) and qualification conversions
3432 (_conv.qual_) are performed to bring them to their composite
3433 pointer type (_expr.rel_). The result is of the composite
3436 --The second and third operands have pointer to member type, or
3437 one has pointer to member type and the other is a null pointer
3438 constant; pointer to member conversions (_conv.mem_) and
3439 qualification conversions (_conv.qual_) are performed to bring
3440 them to a common type, whose cv-qualification shall match the
3441 cv-qualification of either the second or the third operand.
3442 The result is of the common type. */
3443 else if ((null_ptr_cst_p (arg2)
3444 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3445 || (null_ptr_cst_p (arg3)
3446 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3447 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3448 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3449 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3451 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3452 arg3, "conditional expression");
3453 if (result_type == error_mark_node)
3454 return error_mark_node;
3455 arg2 = perform_implicit_conversion (result_type, arg2);
3456 arg3 = perform_implicit_conversion (result_type, arg3);
3461 error ("operands to ?: have different types");
3462 return error_mark_node;
3466 result = fold (build3 (COND_EXPR, result_type, arg1, arg2, arg3));
3467 /* We can't use result_type below, as fold might have returned a
3470 /* Expand both sides into the same slot, hopefully the target of the
3471 ?: expression. We used to check for TARGET_EXPRs here, but now we
3472 sometimes wrap them in NOP_EXPRs so the test would fail. */
3473 if (!lvalue_p && CLASS_TYPE_P (TREE_TYPE (result)))
3474 result = get_target_expr (result);
3476 /* If this expression is an rvalue, but might be mistaken for an
3477 lvalue, we must add a NON_LVALUE_EXPR. */
3478 if (!lvalue_p && real_lvalue_p (result))
3479 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
3484 /* OPERAND is an operand to an expression. Perform necessary steps
3485 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3489 prep_operand (tree operand)
3493 operand = convert_from_reference (operand);
3494 if (CLASS_TYPE_P (TREE_TYPE (operand))
3495 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3496 /* Make sure the template type is instantiated now. */
3497 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3503 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3504 OVERLOAD) to the CANDIDATES, returning an updated list of
3505 CANDIDATES. The ARGS are the arguments provided to the call,
3506 without any implicit object parameter. The EXPLICIT_TARGS are
3507 explicit template arguments provided. TEMPLATE_ONLY is true if
3508 only template functions should be considered. CONVERSION_PATH,
3509 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3512 add_candidates (tree fns, tree args,
3513 tree explicit_targs, bool template_only,
3514 tree conversion_path, tree access_path,
3516 struct z_candidate **candidates)
3519 tree non_static_args;
3521 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3522 /* Delay creating the implicit this parameter until it is needed. */
3523 non_static_args = NULL_TREE;
3530 fn = OVL_CURRENT (fns);
3531 /* Figure out which set of arguments to use. */
3532 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3534 /* If this function is a non-static member, prepend the implicit
3535 object parameter. */
3536 if (!non_static_args)
3537 non_static_args = tree_cons (NULL_TREE,
3538 build_this (TREE_VALUE (args)),
3540 fn_args = non_static_args;
3543 /* Otherwise, just use the list of arguments provided. */
3546 if (TREE_CODE (fn) == TEMPLATE_DECL)
3547 add_template_candidate (candidates,
3557 else if (!template_only)
3558 add_function_candidate (candidates,
3565 fns = OVL_NEXT (fns);
3570 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3573 struct z_candidate *candidates = 0, *cand;
3574 tree arglist, fnname;
3576 tree result = NULL_TREE;
3577 bool result_valid_p = false;
3578 enum tree_code code2 = NOP_EXPR;
3584 if (error_operand_p (arg1)
3585 || error_operand_p (arg2)
3586 || error_operand_p (arg3))
3587 return error_mark_node;
3589 if (code == MODIFY_EXPR)
3591 code2 = TREE_CODE (arg3);
3593 fnname = ansi_assopname (code2);
3596 fnname = ansi_opname (code);
3598 arg1 = prep_operand (arg1);
3604 case VEC_DELETE_EXPR:
3606 /* Use build_op_new_call and build_op_delete_call instead. */
3610 return build_object_call (arg1, arg2);
3616 arg2 = prep_operand (arg2);
3617 arg3 = prep_operand (arg3);
3619 if (code == COND_EXPR)
3621 if (arg2 == NULL_TREE
3622 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3623 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3624 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3625 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3628 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3629 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3632 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3633 arg2 = integer_zero_node;
3635 arglist = NULL_TREE;
3637 arglist = tree_cons (NULL_TREE, arg3, arglist);
3639 arglist = tree_cons (NULL_TREE, arg2, arglist);
3640 arglist = tree_cons (NULL_TREE, arg1, arglist);
3642 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3643 p = conversion_obstack_alloc (0);
3645 /* Add namespace-scope operators to the list of functions to
3647 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3648 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3649 flags, &candidates);
3650 /* Add class-member operators to the candidate set. */
3651 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3655 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3656 if (fns == error_mark_node)
3658 result = error_mark_node;
3659 goto user_defined_result_ready;
3662 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3664 BASELINK_BINFO (fns),
3665 TYPE_BINFO (TREE_TYPE (arg1)),
3666 flags, &candidates);
3669 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3670 to know about two args; a builtin candidate will always have a first
3671 parameter of type bool. We'll handle that in
3672 build_builtin_candidate. */
3673 if (code == COND_EXPR)
3683 args[2] = NULL_TREE;
3686 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3692 /* For these, the built-in candidates set is empty
3693 [over.match.oper]/3. We don't want non-strict matches
3694 because exact matches are always possible with built-in
3695 operators. The built-in candidate set for COMPONENT_REF
3696 would be empty too, but since there are no such built-in
3697 operators, we accept non-strict matches for them. */
3702 strict_p = pedantic;
3706 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3711 case POSTINCREMENT_EXPR:
3712 case POSTDECREMENT_EXPR:
3713 /* Look for an `operator++ (int)'. If they didn't have
3714 one, then we fall back to the old way of doing things. */
3715 if (flags & LOOKUP_COMPLAIN)
3716 pedwarn ("no `%D(int)' declared for postfix `%s', trying prefix operator instead",
3718 operator_name_info[code].name);
3719 if (code == POSTINCREMENT_EXPR)
3720 code = PREINCREMENT_EXPR;
3722 code = PREDECREMENT_EXPR;
3723 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
3727 /* The caller will deal with these. */
3732 result_valid_p = true;
3736 if (flags & LOOKUP_COMPLAIN)
3738 op_error (code, code2, arg1, arg2, arg3, "no match");
3739 print_z_candidates (candidates);
3741 result = error_mark_node;
3747 cand = tourney (candidates);
3750 if (flags & LOOKUP_COMPLAIN)
3752 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3753 print_z_candidates (candidates);
3755 result = error_mark_node;
3757 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3760 *overloaded_p = true;
3763 && fnname == ansi_assopname (NOP_EXPR)
3764 && DECL_ARTIFICIAL (cand->fn)
3766 && ! candidates->next->next)
3768 warning ("using synthesized `%#D' for copy assignment",
3770 cp_warning_at (" where cfront would use `%#D'",
3772 ? candidates->next->fn
3776 result = build_over_call (cand, LOOKUP_NORMAL);
3780 /* Give any warnings we noticed during overload resolution. */
3783 struct candidate_warning *w;
3784 for (w = cand->warnings; w; w = w->next)
3785 joust (cand, w->loser, 1);
3788 /* Check for comparison of different enum types. */
3797 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3798 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3799 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3800 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3802 warning ("comparison between `%#T' and `%#T'",
3803 TREE_TYPE (arg1), TREE_TYPE (arg2));
3810 /* We need to strip any leading REF_BIND so that bitfields
3811 don't cause errors. This should not remove any important
3812 conversions, because builtins don't apply to class
3813 objects directly. */
3814 conv = cand->convs[0];
3815 if (conv->kind == ck_ref_bind)
3816 conv = conv->u.next;
3817 arg1 = convert_like (conv, arg1);
3820 conv = cand->convs[1];
3821 if (conv->kind == ck_ref_bind)
3822 conv = conv->u.next;
3823 arg2 = convert_like (conv, arg2);
3827 conv = cand->convs[2];
3828 if (conv->kind == ck_ref_bind)
3829 conv = conv->u.next;
3830 arg3 = convert_like (conv, arg3);
3835 user_defined_result_ready:
3837 /* Free all the conversions we allocated. */
3838 obstack_free (&conversion_obstack, p);
3840 if (result || result_valid_p)
3847 return build_modify_expr (arg1, code2, arg2);
3850 return build_indirect_ref (arg1, "unary *");
3855 case TRUNC_DIV_EXPR:
3866 case TRUNC_MOD_EXPR:
3870 case TRUTH_ANDIF_EXPR:
3871 case TRUTH_ORIF_EXPR:
3872 return cp_build_binary_op (code, arg1, arg2);
3877 case TRUTH_NOT_EXPR:
3878 case PREINCREMENT_EXPR:
3879 case POSTINCREMENT_EXPR:
3880 case PREDECREMENT_EXPR:
3881 case POSTDECREMENT_EXPR:
3884 return build_unary_op (code, arg1, candidates != 0);
3887 return build_array_ref (arg1, arg2);
3890 return build_conditional_expr (arg1, arg2, arg3);
3893 return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2);
3895 /* The caller will deal with these. */
3907 /* Build a call to operator delete. This has to be handled very specially,
3908 because the restrictions on what signatures match are different from all
3909 other call instances. For a normal delete, only a delete taking (void *)
3910 or (void *, size_t) is accepted. For a placement delete, only an exact
3911 match with the placement new is accepted.
3913 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3914 ADDR is the pointer to be deleted.
3915 SIZE is the size of the memory block to be deleted.
3916 GLOBAL_P is true if the delete-expression should not consider
3917 class-specific delete operators.
3918 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3921 build_op_delete_call (enum tree_code code, tree addr, tree size,
3922 bool global_p, tree placement)
3924 tree fn = NULL_TREE;
3925 tree fns, fnname, argtypes, args, type;
3928 if (addr == error_mark_node)
3929 return error_mark_node;
3931 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3933 fnname = ansi_opname (code);
3935 if (IS_AGGR_TYPE (type) && !global_p)
3938 If the result of the lookup is ambiguous or inaccessible, or if
3939 the lookup selects a placement deallocation function, the
3940 program is ill-formed.
3942 Therefore, we ask lookup_fnfields to complain about ambiguity. */
3944 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3945 if (fns == error_mark_node)
3946 return error_mark_node;
3951 if (fns == NULL_TREE)
3952 fns = lookup_name_nonclass (fnname);
3959 /* Find the allocation function that is being called. */
3960 call_expr = placement;
3961 /* Extract the function. */
3962 alloc_fn = get_callee_fndecl (call_expr);
3963 my_friendly_assert (alloc_fn != NULL_TREE, 20020327);
3964 /* Then the second parm type. */
3965 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3966 /* Also the second argument. */
3967 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3971 /* First try it without the size argument. */
3972 argtypes = void_list_node;
3976 /* Strip const and volatile from addr. */
3977 addr = cp_convert (ptr_type_node, addr);
3979 /* We make two tries at finding a matching `operator delete'. On
3980 the first pass, we look for a one-operator (or placement)
3981 operator delete. If we're not doing placement delete, then on
3982 the second pass we look for a two-argument delete. */
3983 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
3985 /* Go through the `operator delete' functions looking for one
3986 with a matching type. */
3987 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
3993 /* The first argument must be "void *". */
3994 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
3995 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
3998 /* On the first pass, check the rest of the arguments. */
4004 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4012 /* On the second pass, the second argument must be
4015 && same_type_p (TREE_VALUE (t), sizetype)
4016 && TREE_CHAIN (t) == void_list_node)
4020 /* If we found a match, we're done. */
4025 /* If we have a matching function, call it. */
4028 /* Make sure we have the actual function, and not an
4030 fn = OVL_CURRENT (fn);
4032 /* If the FN is a member function, make sure that it is
4034 if (DECL_CLASS_SCOPE_P (fn))
4035 perform_or_defer_access_check (TYPE_BINFO (type), fn);
4038 args = tree_cons (NULL_TREE, addr, args);
4040 args = tree_cons (NULL_TREE, addr,
4041 build_tree_list (NULL_TREE, size));
4045 /* The placement args might not be suitable for overload
4046 resolution at this point, so build the call directly. */
4048 return build_cxx_call (fn, args);
4051 return build_function_call (fn, args);
4054 /* If we are doing placement delete we do nothing if we don't find a
4055 matching op delete. */
4059 error ("no suitable `operator %s' for `%T'",
4060 operator_name_info[(int)code].name, type);
4061 return error_mark_node;
4064 /* If the current scope isn't allowed to access DECL along
4065 BASETYPE_PATH, give an error. The most derived class in
4066 BASETYPE_PATH is the one used to qualify DECL. */
4069 enforce_access (tree basetype_path, tree decl)
4071 my_friendly_assert (TREE_CODE (basetype_path) == TREE_BINFO, 20030624);
4073 if (!accessible_p (basetype_path, decl))
4075 if (TREE_PRIVATE (decl))
4076 cp_error_at ("`%+#D' is private", decl);
4077 else if (TREE_PROTECTED (decl))
4078 cp_error_at ("`%+#D' is protected", decl);
4080 cp_error_at ("`%+#D' is inaccessible", decl);
4081 error ("within this context");
4088 /* Check that a callable constructor to initialize a temporary of
4089 TYPE from an EXPR exists. */
4092 check_constructor_callable (tree type, tree expr)
4094 build_special_member_call (NULL_TREE,
4095 complete_ctor_identifier,
4096 build_tree_list (NULL_TREE, expr),
4098 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING
4099 | LOOKUP_CONSTRUCTOR_CALLABLE);
4102 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4103 bitwise or of LOOKUP_* values. If any errors are warnings are
4104 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4105 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4109 build_temp (tree expr, tree type, int flags,
4110 void (**diagnostic_fn)(const char *, ...))
4114 savew = warningcount, savee = errorcount;
4115 expr = build_special_member_call (NULL_TREE,
4116 complete_ctor_identifier,
4117 build_tree_list (NULL_TREE, expr),
4119 if (warningcount > savew)
4120 *diagnostic_fn = warning;
4121 else if (errorcount > savee)
4122 *diagnostic_fn = error;
4124 *diagnostic_fn = NULL;
4129 /* Perform the conversions in CONVS on the expression EXPR. FN and
4130 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4131 indicates the `this' argument of a method. INNER is nonzero when
4132 being called to continue a conversion chain. It is negative when a
4133 reference binding will be applied, positive otherwise. If
4134 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4135 conversions will be emitted if appropriate. */
4138 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4139 int inner, bool issue_conversion_warnings)
4141 tree totype = convs->type;
4142 void (*diagnostic_fn)(const char *, ...);
4145 && convs->kind != ck_user
4146 && convs->kind != ck_ambig
4147 && convs->kind != ck_ref_bind)
4149 conversion *t = convs;
4150 for (; t; t = convs->u.next)
4152 if (t->kind == ck_user || !t->bad_p)
4154 expr = convert_like_real (t, expr, fn, argnum, 1,
4155 /*issue_conversion_warnings=*/false);
4158 else if (t->kind == ck_ambig)
4159 return convert_like_real (t, expr, fn, argnum, 1,
4160 /*issue_conversion_warnings=*/false);
4161 else if (t->kind == ck_identity)
4164 pedwarn ("invalid conversion from `%T' to `%T'", TREE_TYPE (expr), totype);
4166 pedwarn (" initializing argument %P of `%D'", argnum, fn);
4167 return cp_convert (totype, expr);
4170 if (issue_conversion_warnings)
4171 expr = dubious_conversion_warnings
4172 (totype, expr, "converting", fn, argnum);
4173 switch (convs->kind)
4177 struct z_candidate *cand = convs->cand;
4178 tree convfn = cand->fn;
4181 if (DECL_CONSTRUCTOR_P (convfn))
4183 tree t = build_int_cst (build_pointer_type (DECL_CONTEXT (convfn)),
4186 args = build_tree_list (NULL_TREE, expr);
4187 if (DECL_HAS_IN_CHARGE_PARM_P (convfn)
4188 || DECL_HAS_VTT_PARM_P (convfn))
4189 /* We should never try to call the abstract or base constructor
4192 args = tree_cons (NULL_TREE, t, args);
4195 args = build_this (expr);
4196 expr = build_over_call (cand, LOOKUP_NORMAL);
4198 /* If this is a constructor or a function returning an aggr type,
4199 we need to build up a TARGET_EXPR. */
4200 if (DECL_CONSTRUCTOR_P (convfn))
4201 expr = build_cplus_new (totype, expr);
4203 /* The result of the call is then used to direct-initialize the object
4204 that is the destination of the copy-initialization. [dcl.init]
4206 Note that this step is not reflected in the conversion sequence;
4207 it affects the semantics when we actually perform the
4208 conversion, but is not considered during overload resolution.
4210 If the target is a class, that means call a ctor. */
4211 if (IS_AGGR_TYPE (totype)
4212 && (inner >= 0 || !lvalue_p (expr)))
4216 /* Core issue 84, now a DR, says that we don't
4217 allow UDCs for these args (which deliberately
4218 breaks copy-init of an auto_ptr<Base> from an
4219 auto_ptr<Derived>). */
4220 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION,
4227 (" initializing argument %P of `%D' from result of `%D'",
4228 argnum, fn, convfn);
4231 (" initializing temporary from result of `%D'", convfn);
4233 expr = build_cplus_new (totype, expr);
4238 if (type_unknown_p (expr))
4239 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4240 /* Convert a non-array constant variable to its underlying value, unless we
4241 are about to bind it to a reference, in which case we need to
4242 leave it as an lvalue. */
4244 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
4245 expr = decl_constant_value (expr);
4246 if (convs->check_copy_constructor_p)
4247 check_constructor_callable (totype, expr);
4250 /* Call build_user_type_conversion again for the error. */
4251 return build_user_type_conversion
4252 (totype, convs->u.expr, LOOKUP_NORMAL);
4258 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4259 convs->kind == ck_ref_bind ? -1 : 1,
4260 /*issue_conversion_warnings=*/false);
4261 if (expr == error_mark_node)
4262 return error_mark_node;
4264 switch (convs->kind)
4267 if (! IS_AGGR_TYPE (totype))
4269 /* Else fall through. */
4271 if (convs->kind == ck_base && !convs->need_temporary_p)
4273 /* We are going to bind a reference directly to a base-class
4274 subobject of EXPR. */
4275 if (convs->check_copy_constructor_p)
4276 check_constructor_callable (TREE_TYPE (expr), expr);
4277 /* Build an expression for `*((base*) &expr)'. */
4278 expr = build_unary_op (ADDR_EXPR, expr, 0);
4279 expr = perform_implicit_conversion (build_pointer_type (totype),
4281 expr = build_indirect_ref (expr, "implicit conversion");
4285 /* Copy-initialization where the cv-unqualified version of the source
4286 type is the same class as, or a derived class of, the class of the
4287 destination [is treated as direct-initialization]. [dcl.init] */
4288 expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
4290 if (diagnostic_fn && fn)
4291 diagnostic_fn (" initializing argument %P of `%D'", argnum, fn);
4292 return build_cplus_new (totype, expr);
4296 tree ref_type = totype;
4298 /* If necessary, create a temporary. */
4299 if (convs->need_temporary_p || !lvalue_p (expr))
4301 tree type = convs->u.next->type;
4303 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
4305 /* If the reference is volatile or non-const, we
4306 cannot create a temporary. */
4307 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4309 if (lvalue & clk_bitfield)
4310 error ("cannot bind bitfield `%E' to `%T'",
4312 else if (lvalue & clk_packed)
4313 error ("cannot bind packed field `%E' to `%T'",
4316 error ("cannot bind rvalue `%E' to `%T'", expr, ref_type);
4317 return error_mark_node;
4319 expr = build_target_expr_with_type (expr, type);
4322 /* Take the address of the thing to which we will bind the
4324 expr = build_unary_op (ADDR_EXPR, expr, 1);
4325 if (expr == error_mark_node)
4326 return error_mark_node;
4328 /* Convert it to a pointer to the type referred to by the
4329 reference. This will adjust the pointer if a derived to
4330 base conversion is being performed. */
4331 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4333 /* Convert the pointer to the desired reference type. */
4334 return build_nop (ref_type, expr);
4338 return decay_conversion (expr);
4341 /* Warn about deprecated conversion if appropriate. */
4342 string_conv_p (totype, expr, 1);
4348 return ocp_convert (totype, expr, CONV_IMPLICIT,
4349 LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
4352 /* Build a call to __builtin_trap. */
4355 call_builtin_trap (void)
4357 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4359 my_friendly_assert (fn != NULL, 20030927);
4360 fn = build_call (fn, NULL_TREE);
4364 /* ARG is being passed to a varargs function. Perform any conversions
4365 required. Return the converted value. */
4368 convert_arg_to_ellipsis (tree arg)
4372 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4373 standard conversions are performed. */
4374 arg = decay_conversion (arg);
4377 If the argument has integral or enumeration type that is subject
4378 to the integral promotions (_conv.prom_), or a floating point
4379 type that is subject to the floating point promotion
4380 (_conv.fpprom_), the value of the argument is converted to the
4381 promoted type before the call. */
4382 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4383 && (TYPE_PRECISION (TREE_TYPE (arg))
4384 < TYPE_PRECISION (double_type_node)))
4385 arg = convert_to_real (double_type_node, arg);
4386 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4387 arg = perform_integral_promotions (arg);
4389 arg = require_complete_type (arg);
4391 if (arg != error_mark_node
4392 && !pod_type_p (TREE_TYPE (arg)))
4394 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4395 here and do a bitwise copy, but now cp_expr_size will abort if we
4397 If the call appears in the context of a sizeof expression,
4398 there is no need to emit a warning, since the expression won't be
4399 evaluated. We keep the builtin_trap just as a safety check. */
4400 if (!skip_evaluation)
4401 warning ("cannot pass objects of non-POD type `%#T' through `...'; "
4402 "call will abort at runtime", TREE_TYPE (arg));
4403 arg = call_builtin_trap ();
4404 arg = build2 (COMPOUND_EXPR, integer_type_node, arg,
4411 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4414 build_x_va_arg (tree expr, tree type)
4416 if (processing_template_decl)
4417 return build_min (VA_ARG_EXPR, type, expr);
4419 type = complete_type_or_else (type, NULL_TREE);
4421 if (expr == error_mark_node || !type)
4422 return error_mark_node;
4424 if (! pod_type_p (type))
4426 /* Undefined behavior [expr.call] 5.2.2/7. */
4427 warning ("cannot receive objects of non-POD type `%#T' through `...'; \
4428 call will abort at runtime",
4430 expr = convert (build_pointer_type (type), null_node);
4431 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr),
4432 call_builtin_trap (), expr);
4433 expr = build_indirect_ref (expr, NULL);
4437 return build_va_arg (expr, type);
4440 /* TYPE has been given to va_arg. Apply the default conversions which
4441 would have happened when passed via ellipsis. Return the promoted
4442 type, or the passed type if there is no change. */
4445 cxx_type_promotes_to (tree type)
4449 /* Perform the array-to-pointer and function-to-pointer
4451 type = type_decays_to (type);
4453 promote = type_promotes_to (type);
4454 if (same_type_p (type, promote))
4460 /* ARG is a default argument expression being passed to a parameter of
4461 the indicated TYPE, which is a parameter to FN. Do any required
4462 conversions. Return the converted value. */
4465 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4467 /* If the ARG is an unparsed default argument expression, the
4468 conversion cannot be performed. */
4469 if (TREE_CODE (arg) == DEFAULT_ARG)
4471 error ("the default argument for parameter %d of `%D' has "
4472 "not yet been parsed",
4474 return error_mark_node;
4477 if (fn && DECL_TEMPLATE_INFO (fn))
4478 arg = tsubst_default_argument (fn, type, arg);
4480 arg = break_out_target_exprs (arg);
4482 if (TREE_CODE (arg) == CONSTRUCTOR)
4484 arg = digest_init (type, arg, 0);
4485 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4486 "default argument", fn, parmnum);
4490 /* This could get clobbered by the following call. */
4491 if (TREE_HAS_CONSTRUCTOR (arg))
4492 arg = copy_node (arg);
4494 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4495 "default argument", fn, parmnum);
4496 arg = convert_for_arg_passing (type, arg);
4502 /* Returns the type which will really be used for passing an argument of
4506 type_passed_as (tree type)
4508 /* Pass classes with copy ctors by invisible reference. */
4509 if (TREE_ADDRESSABLE (type))
4511 type = build_reference_type (type);
4512 /* There are no other pointers to this temporary. */
4513 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4515 else if (targetm.calls.promote_prototypes (type)
4516 && INTEGRAL_TYPE_P (type)
4517 && COMPLETE_TYPE_P (type)
4518 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4519 TYPE_SIZE (integer_type_node)))
4520 type = integer_type_node;
4525 /* Actually perform the appropriate conversion. */
4528 convert_for_arg_passing (tree type, tree val)
4530 if (val == error_mark_node)
4532 /* Pass classes with copy ctors by invisible reference. */
4533 else if (TREE_ADDRESSABLE (type))
4534 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4535 else if (targetm.calls.promote_prototypes (type)
4536 && INTEGRAL_TYPE_P (type)
4537 && COMPLETE_TYPE_P (type)
4538 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4539 TYPE_SIZE (integer_type_node)))
4540 val = perform_integral_promotions (val);
4544 /* Returns true iff FN is a function with magic varargs, i.e. ones for
4545 which no conversions at all should be done. This is true for some
4546 builtins which don't act like normal functions. */
4549 magic_varargs_p (tree fn)
4551 if (DECL_BUILT_IN (fn))
4552 switch (DECL_FUNCTION_CODE (fn))
4554 case BUILT_IN_CLASSIFY_TYPE:
4555 case BUILT_IN_CONSTANT_P:
4556 case BUILT_IN_NEXT_ARG:
4557 case BUILT_IN_STDARG_START:
4558 case BUILT_IN_VA_START:
4567 /* Subroutine of the various build_*_call functions. Overload resolution
4568 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4569 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4570 bitmask of various LOOKUP_* flags which apply to the call itself. */
4573 build_over_call (struct z_candidate *cand, int flags)
4576 tree args = cand->args;
4577 conversion **convs = cand->convs;
4579 tree converted_args = NULL_TREE;
4580 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4585 /* In a template, there is no need to perform all of the work that
4586 is normally done. We are only interested in the type of the call
4587 expression, i.e., the return type of the function. Any semantic
4588 errors will be deferred until the template is instantiated. */
4589 if (processing_template_decl)
4593 return_type = TREE_TYPE (TREE_TYPE (fn));
4594 expr = build3 (CALL_EXPR, return_type, fn, args, NULL_TREE);
4595 if (TREE_THIS_VOLATILE (fn) && cfun)
4596 current_function_returns_abnormally = 1;
4597 if (!VOID_TYPE_P (return_type))
4598 require_complete_type (return_type);
4599 return convert_from_reference (expr);
4602 /* Give any warnings we noticed during overload resolution. */
4605 struct candidate_warning *w;
4606 for (w = cand->warnings; w; w = w->next)
4607 joust (cand, w->loser, 1);
4610 if (DECL_FUNCTION_MEMBER_P (fn))
4612 /* If FN is a template function, two cases must be considered.
4617 template <class T> void f();
4619 template <class T> struct B {
4623 struct C : A, B<int> {
4625 using B<int>::g; // #2
4628 In case #1 where `A::f' is a member template, DECL_ACCESS is
4629 recorded in the primary template but not in its specialization.
4630 We check access of FN using its primary template.
4632 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
4633 because it is a member of class template B, DECL_ACCESS is
4634 recorded in the specialization `B<int>::g'. We cannot use its
4635 primary template because `B<T>::g' and `B<int>::g' may have
4636 different access. */
4637 if (DECL_TEMPLATE_INFO (fn)
4638 && is_member_template (DECL_TI_TEMPLATE (fn)))
4639 perform_or_defer_access_check (cand->access_path,
4640 DECL_TI_TEMPLATE (fn));
4642 perform_or_defer_access_check (cand->access_path, fn);
4645 if (args && TREE_CODE (args) != TREE_LIST)
4646 args = build_tree_list (NULL_TREE, args);
4649 /* The implicit parameters to a constructor are not considered by overload
4650 resolution, and must be of the proper type. */
4651 if (DECL_CONSTRUCTOR_P (fn))
4653 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4654 arg = TREE_CHAIN (arg);
4655 parm = TREE_CHAIN (parm);
4656 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
4657 /* We should never try to call the abstract constructor. */
4659 if (DECL_HAS_VTT_PARM_P (fn))
4661 converted_args = tree_cons
4662 (NULL_TREE, TREE_VALUE (arg), converted_args);
4663 arg = TREE_CHAIN (arg);
4664 parm = TREE_CHAIN (parm);
4667 /* Bypass access control for 'this' parameter. */
4668 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4670 tree parmtype = TREE_VALUE (parm);
4671 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4675 if (convs[i]->bad_p)
4676 pedwarn ("passing `%T' as `this' argument of `%#D' discards qualifiers",
4677 TREE_TYPE (argtype), fn);
4679 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4680 X is called for an object that is not of type X, or of a type
4681 derived from X, the behavior is undefined.
4683 So we can assume that anything passed as 'this' is non-null, and
4684 optimize accordingly. */
4685 my_friendly_assert (TREE_CODE (parmtype) == POINTER_TYPE, 19990811);
4686 /* Convert to the base in which the function was declared. */
4687 my_friendly_assert (cand->conversion_path != NULL_TREE, 20020730);
4688 converted_arg = build_base_path (PLUS_EXPR,
4690 cand->conversion_path,
4692 /* Check that the base class is accessible. */
4693 if (!accessible_base_p (TREE_TYPE (argtype),
4694 BINFO_TYPE (cand->conversion_path)))
4695 error ("`%T' is not an accessible base of `%T'",
4696 BINFO_TYPE (cand->conversion_path),
4697 TREE_TYPE (argtype));
4698 /* If fn was found by a using declaration, the conversion path
4699 will be to the derived class, not the base declaring fn. We
4700 must convert from derived to base. */
4701 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4702 TREE_TYPE (parmtype), ba_ignore, NULL);
4703 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4706 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4707 parm = TREE_CHAIN (parm);
4708 arg = TREE_CHAIN (arg);
4714 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4716 tree type = TREE_VALUE (parm);
4719 val = convert_like_with_context
4720 (conv, TREE_VALUE (arg), fn, i - is_method);
4722 val = convert_for_arg_passing (type, val);
4723 converted_args = tree_cons (NULL_TREE, val, converted_args);
4726 /* Default arguments */
4727 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4729 = tree_cons (NULL_TREE,
4730 convert_default_arg (TREE_VALUE (parm),
4731 TREE_PURPOSE (parm),
4736 for (; arg; arg = TREE_CHAIN (arg))
4738 tree a = TREE_VALUE (arg);
4739 if (magic_varargs_p (fn))
4740 /* Do no conversions for magic varargs. */;
4742 a = convert_arg_to_ellipsis (a);
4743 converted_args = tree_cons (NULL_TREE, a, converted_args);
4746 converted_args = nreverse (converted_args);
4748 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4751 /* Avoid actually calling copy constructors and copy assignment operators,
4754 if (! flag_elide_constructors)
4755 /* Do things the hard way. */;
4756 else if (cand->num_convs == 1 && DECL_COPY_CONSTRUCTOR_P (fn))
4759 arg = skip_artificial_parms_for (fn, converted_args);
4760 arg = TREE_VALUE (arg);
4762 /* Pull out the real argument, disregarding const-correctness. */
4764 while (TREE_CODE (targ) == NOP_EXPR
4765 || TREE_CODE (targ) == NON_LVALUE_EXPR
4766 || TREE_CODE (targ) == CONVERT_EXPR)
4767 targ = TREE_OPERAND (targ, 0);
4768 if (TREE_CODE (targ) == ADDR_EXPR)
4770 targ = TREE_OPERAND (targ, 0);
4771 if (!same_type_ignoring_top_level_qualifiers_p
4772 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4781 arg = build_indirect_ref (arg, 0);
4783 /* [class.copy]: the copy constructor is implicitly defined even if
4784 the implementation elided its use. */
4785 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4788 /* If we're creating a temp and we already have one, don't create a
4789 new one. If we're not creating a temp but we get one, use
4790 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4791 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4792 temp or an INIT_EXPR otherwise. */
4793 if (integer_zerop (TREE_VALUE (args)))
4795 if (TREE_CODE (arg) == TARGET_EXPR)
4797 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4798 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4800 else if (TREE_CODE (arg) == TARGET_EXPR
4801 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4803 tree to = stabilize_reference
4804 (build_indirect_ref (TREE_VALUE (args), 0));
4806 val = build2 (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4810 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4812 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4814 tree to = stabilize_reference
4815 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4816 tree type = TREE_TYPE (to);
4817 tree as_base = CLASSTYPE_AS_BASE (type);
4819 arg = TREE_VALUE (TREE_CHAIN (converted_args));
4820 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
4822 arg = build_indirect_ref (arg, 0);
4823 val = build2 (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4827 /* We must only copy the non-tail padding parts.
4828 Use __builtin_memcpy for the bitwise copy. */
4832 args = tree_cons (NULL, TYPE_SIZE_UNIT (as_base), NULL);
4833 args = tree_cons (NULL, arg, args);
4834 t = build_unary_op (ADDR_EXPR, to, 0);
4835 args = tree_cons (NULL, t, args);
4836 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
4837 t = build_call (t, args);
4839 t = convert (TREE_TYPE (TREE_VALUE (args)), t);
4840 val = build_indirect_ref (t, 0);
4848 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4850 tree t, *p = &TREE_VALUE (converted_args);
4851 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4854 my_friendly_assert (binfo && binfo != error_mark_node, 20010730);
4856 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4857 if (TREE_SIDE_EFFECTS (*p))
4858 *p = save_expr (*p);
4859 t = build_pointer_type (TREE_TYPE (fn));
4860 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4861 fn = build_java_interface_fn_ref (fn, *p);
4863 fn = build_vfn_ref (*p, DECL_VINDEX (fn));
4866 else if (DECL_INLINE (fn))
4867 fn = inline_conversion (fn);
4869 fn = build_addr_func (fn);
4871 return build_cxx_call (fn, converted_args);
4874 /* Build and return a call to FN, using ARGS. This function performs
4875 no overload resolution, conversion, or other high-level
4879 build_cxx_call (tree fn, tree args)
4883 fn = build_call (fn, args);
4885 /* If this call might throw an exception, note that fact. */
4886 fndecl = get_callee_fndecl (fn);
4887 if ((!fndecl || !TREE_NOTHROW (fndecl))
4888 && at_function_scope_p ()
4890 cp_function_chain->can_throw = 1;
4892 /* Some built-in function calls will be evaluated at compile-time in
4896 if (VOID_TYPE_P (TREE_TYPE (fn)))
4899 fn = require_complete_type (fn);
4900 if (fn == error_mark_node)
4901 return error_mark_node;
4903 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4904 fn = build_cplus_new (TREE_TYPE (fn), fn);
4905 return convert_from_reference (fn);
4908 static GTY(()) tree java_iface_lookup_fn;
4910 /* Make an expression which yields the address of the Java interface
4911 method FN. This is achieved by generating a call to libjava's
4912 _Jv_LookupInterfaceMethodIdx(). */
4915 build_java_interface_fn_ref (tree fn, tree instance)
4917 tree lookup_args, lookup_fn, method, idx;
4918 tree klass_ref, iface, iface_ref;
4921 if (!java_iface_lookup_fn)
4923 tree endlink = build_void_list_node ();
4924 tree t = tree_cons (NULL_TREE, ptr_type_node,
4925 tree_cons (NULL_TREE, ptr_type_node,
4926 tree_cons (NULL_TREE, java_int_type_node,
4928 java_iface_lookup_fn
4929 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
4930 build_function_type (ptr_type_node, t),
4931 0, NOT_BUILT_IN, NULL, NULL_TREE);
4934 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
4935 This is the first entry in the vtable. */
4936 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
4939 /* Get the java.lang.Class pointer for the interface being called. */
4940 iface = DECL_CONTEXT (fn);
4941 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
4942 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
4943 || DECL_CONTEXT (iface_ref) != iface)
4945 error ("could not find class$ field in java interface type `%T'",
4947 return error_mark_node;
4949 iface_ref = build_address (iface_ref);
4950 iface_ref = convert (build_pointer_type (iface), iface_ref);
4952 /* Determine the itable index of FN. */
4954 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
4956 if (!DECL_VIRTUAL_P (method))
4962 idx = build_int_cst (NULL_TREE, i, 0);
4964 lookup_args = tree_cons (NULL_TREE, klass_ref,
4965 tree_cons (NULL_TREE, iface_ref,
4966 build_tree_list (NULL_TREE, idx)));
4967 lookup_fn = build1 (ADDR_EXPR,
4968 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
4969 java_iface_lookup_fn);
4970 return build3 (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
4973 /* Returns the value to use for the in-charge parameter when making a
4974 call to a function with the indicated NAME. */
4977 in_charge_arg_for_name (tree name)
4979 if (name == base_ctor_identifier
4980 || name == base_dtor_identifier)
4981 return integer_zero_node;
4982 else if (name == complete_ctor_identifier)
4983 return integer_one_node;
4984 else if (name == complete_dtor_identifier)
4985 return integer_two_node;
4986 else if (name == deleting_dtor_identifier)
4987 return integer_three_node;
4989 /* This function should only be called with one of the names listed
4995 /* Build a call to a constructor, destructor, or an assignment
4996 operator for INSTANCE, an expression with class type. NAME
4997 indicates the special member function to call; ARGS are the
4998 arguments. BINFO indicates the base of INSTANCE that is to be
4999 passed as the `this' parameter to the member function called.
5001 FLAGS are the LOOKUP_* flags to use when processing the call.
5003 If NAME indicates a complete object constructor, INSTANCE may be
5004 NULL_TREE. In this case, the caller will call build_cplus_new to
5005 store the newly constructed object into a VAR_DECL. */
5008 build_special_member_call (tree instance, tree name, tree args,
5009 tree binfo, int flags)
5012 /* The type of the subobject to be constructed or destroyed. */
5015 my_friendly_assert (name == complete_ctor_identifier
5016 || name == base_ctor_identifier
5017 || name == complete_dtor_identifier
5018 || name == base_dtor_identifier
5019 || name == deleting_dtor_identifier
5020 || name == ansi_assopname (NOP_EXPR),
5024 /* Resolve the name. */
5025 if (!complete_type_or_else (binfo, NULL_TREE))
5026 return error_mark_node;
5028 binfo = TYPE_BINFO (binfo);
5031 my_friendly_assert (binfo != NULL_TREE, 20020712);
5033 class_type = BINFO_TYPE (binfo);
5035 /* Handle the special case where INSTANCE is NULL_TREE. */
5036 if (name == complete_ctor_identifier && !instance)
5038 instance = build_int_cst (build_pointer_type (class_type), 0, 0);
5039 instance = build1 (INDIRECT_REF, class_type, instance);
5043 if (name == complete_dtor_identifier
5044 || name == base_dtor_identifier
5045 || name == deleting_dtor_identifier)
5046 my_friendly_assert (args == NULL_TREE, 20020712);
5048 /* Convert to the base class, if necessary. */
5049 if (!same_type_ignoring_top_level_qualifiers_p
5050 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5052 if (name != ansi_assopname (NOP_EXPR))
5053 /* For constructors and destructors, either the base is
5054 non-virtual, or it is virtual but we are doing the
5055 conversion from a constructor or destructor for the
5056 complete object. In either case, we can convert
5058 instance = convert_to_base_statically (instance, binfo);
5060 /* However, for assignment operators, we must convert
5061 dynamically if the base is virtual. */
5062 instance = build_base_path (PLUS_EXPR, instance,
5063 binfo, /*nonnull=*/1);
5067 my_friendly_assert (instance != NULL_TREE, 20020712);
5069 fns = lookup_fnfields (binfo, name, 1);
5071 /* When making a call to a constructor or destructor for a subobject
5072 that uses virtual base classes, pass down a pointer to a VTT for
5074 if ((name == base_ctor_identifier
5075 || name == base_dtor_identifier)
5076 && TYPE_USES_VIRTUAL_BASECLASSES (class_type))
5081 /* If the current function is a complete object constructor
5082 or destructor, then we fetch the VTT directly.
5083 Otherwise, we look it up using the VTT we were given. */
5084 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5085 vtt = decay_conversion (vtt);
5086 vtt = build3 (COND_EXPR, TREE_TYPE (vtt),
5087 build2 (EQ_EXPR, boolean_type_node,
5088 current_in_charge_parm, integer_zero_node),
5091 my_friendly_assert (BINFO_SUBVTT_INDEX (binfo), 20010110);
5092 sub_vtt = build2 (PLUS_EXPR, TREE_TYPE (vtt), vtt,
5093 BINFO_SUBVTT_INDEX (binfo));
5095 args = tree_cons (NULL_TREE, sub_vtt, args);
5098 return build_new_method_call (instance, fns, args,
5099 TYPE_BINFO (BINFO_TYPE (binfo)),
5103 /* Return the NAME, as a C string. The NAME indicates a function that
5104 is a member of TYPE. *FREE_P is set to true if the caller must
5105 free the memory returned.
5107 Rather than go through all of this, we should simply set the names
5108 of constructors and destructors appropriately, and dispense with
5109 ctor_identifier, dtor_identifier, etc. */
5112 name_as_c_string (tree name, tree type, bool *free_p)
5116 /* Assume that we will not allocate memory. */
5118 /* Constructors and destructors are special. */
5119 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5122 = (char *) IDENTIFIER_POINTER (constructor_name (type));
5123 /* For a destructor, add the '~'. */
5124 if (name == complete_dtor_identifier
5125 || name == base_dtor_identifier
5126 || name == deleting_dtor_identifier)
5128 pretty_name = concat ("~", pretty_name, NULL);
5129 /* Remember that we need to free the memory allocated. */
5133 else if (IDENTIFIER_TYPENAME_P (name))
5135 pretty_name = concat ("operator ",
5136 type_as_string (TREE_TYPE (name),
5137 TFF_PLAIN_IDENTIFIER),
5139 /* Remember that we need to free the memory allocated. */
5143 pretty_name = (char *) IDENTIFIER_POINTER (name);
5148 /* Build a call to "INSTANCE.FN (ARGS)". */
5151 build_new_method_call (tree instance, tree fns, tree args,
5152 tree conversion_path, int flags)
5154 struct z_candidate *candidates = 0, *cand;
5155 tree explicit_targs = NULL_TREE;
5156 tree basetype = NULL_TREE;
5159 tree mem_args = NULL_TREE, instance_ptr;
5165 int template_only = 0;
5172 my_friendly_assert (instance != NULL_TREE, 20020729);
5174 if (error_operand_p (instance)
5175 || error_operand_p (fns)
5176 || args == error_mark_node)
5177 return error_mark_node;
5179 orig_instance = instance;
5183 if (processing_template_decl)
5185 instance = build_non_dependent_expr (instance);
5186 if (!BASELINK_P (fns)
5187 && TREE_CODE (fns) != PSEUDO_DTOR_EXPR
5188 && TREE_TYPE (fns) != unknown_type_node)
5189 fns = build_non_dependent_expr (fns);
5190 args = build_non_dependent_args (orig_args);
5193 /* Process the argument list. */
5195 args = resolve_args (args);
5196 if (args == error_mark_node)
5197 return error_mark_node;
5199 if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5200 instance = convert_from_reference (instance);
5201 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5202 instance_ptr = build_this (instance);
5204 if (!BASELINK_P (fns))
5206 error ("call to non-function `%D'", fns);
5207 return error_mark_node;
5210 if (!conversion_path)
5211 conversion_path = BASELINK_BINFO (fns);
5212 access_binfo = BASELINK_ACCESS_BINFO (fns);
5213 optype = BASELINK_OPTYPE (fns);
5214 fns = BASELINK_FUNCTIONS (fns);
5216 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5218 explicit_targs = TREE_OPERAND (fns, 1);
5219 fns = TREE_OPERAND (fns, 0);
5223 my_friendly_assert (TREE_CODE (fns) == FUNCTION_DECL
5224 || TREE_CODE (fns) == TEMPLATE_DECL
5225 || TREE_CODE (fns) == OVERLOAD,
5228 /* XXX this should be handled before we get here. */
5229 if (! IS_AGGR_TYPE (basetype))
5231 if ((flags & LOOKUP_COMPLAIN) && basetype != error_mark_node)
5232 error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
5233 fns, instance, basetype);
5235 return error_mark_node;
5238 fn = get_first_fn (fns);
5239 name = DECL_NAME (fn);
5241 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5243 /* Callers should explicitly indicate whether they want to construct
5244 the complete object or just the part without virtual bases. */
5245 my_friendly_assert (name != ctor_identifier, 20000408);
5246 /* Similarly for destructors. */
5247 my_friendly_assert (name != dtor_identifier, 20000408);
5250 /* It's OK to call destructors on cv-qualified objects. Therefore,
5251 convert the INSTANCE_PTR to the unqualified type, if necessary. */
5252 if (DECL_DESTRUCTOR_P (fn))
5254 tree type = build_pointer_type (basetype);
5255 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5256 instance_ptr = build_nop (type, instance_ptr);
5259 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5260 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5262 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5263 p = conversion_obstack_alloc (0);
5265 for (fn = fns; fn; fn = OVL_NEXT (fn))
5267 tree t = OVL_CURRENT (fn);
5270 /* We can end up here for copy-init of same or base class. */
5271 if ((flags & LOOKUP_ONLYCONVERTING)
5272 && DECL_NONCONVERTING_P (t))
5275 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5276 this_arglist = mem_args;
5278 this_arglist = args;
5280 if (TREE_CODE (t) == TEMPLATE_DECL)
5281 /* A member template. */
5282 add_template_candidate (&candidates, t,
5285 this_arglist, optype,
5290 else if (! template_only)
5291 add_function_candidate (&candidates, t,
5299 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5302 if (!COMPLETE_TYPE_P (basetype))
5303 cxx_incomplete_type_error (instance_ptr, basetype);
5309 pretty_name = name_as_c_string (name, basetype, &free_p);
5310 error ("no matching function for call to `%T::%s(%A)%#V'",
5311 basetype, pretty_name, user_args,
5312 TREE_TYPE (TREE_TYPE (instance_ptr)));
5316 print_z_candidates (candidates);
5317 call = error_mark_node;
5321 cand = tourney (candidates);
5327 pretty_name = name_as_c_string (name, basetype, &free_p);
5328 error ("call of overloaded `%s(%A)' is ambiguous", pretty_name,
5330 print_z_candidates (candidates);
5333 call = error_mark_node;
5337 if (DECL_PURE_VIRTUAL_P (cand->fn)
5338 && instance == current_class_ref
5339 && (DECL_CONSTRUCTOR_P (current_function_decl)
5340 || DECL_DESTRUCTOR_P (current_function_decl))
5341 && ! (flags & LOOKUP_NONVIRTUAL)
5342 && value_member (cand->fn, CLASSTYPE_PURE_VIRTUALS (basetype)))
5343 error ((DECL_CONSTRUCTOR_P (current_function_decl) ?
5344 "abstract virtual `%#D' called from constructor"
5345 : "abstract virtual `%#D' called from destructor"),
5347 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5348 && is_dummy_object (instance_ptr))
5350 error ("cannot call member function `%D' without object",
5352 call = error_mark_node;
5356 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5357 && resolves_to_fixed_type_p (instance, 0))
5358 flags |= LOOKUP_NONVIRTUAL;
5360 call = build_over_call (cand, flags);
5362 /* In an expression of the form `a->f()' where `f' turns
5363 out to be a static member function, `a' is
5364 none-the-less evaluated. */
5365 if (TREE_CODE (TREE_TYPE (cand->fn)) != METHOD_TYPE
5366 && !is_dummy_object (instance_ptr)
5367 && TREE_SIDE_EFFECTS (instance))
5368 call = build2 (COMPOUND_EXPR, TREE_TYPE (call),
5374 if (processing_template_decl && call != error_mark_node)
5375 call = (build_min_non_dep
5377 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5378 orig_args, NULL_TREE));
5380 /* Free all the conversions we allocated. */
5381 obstack_free (&conversion_obstack, p);
5386 /* Returns true iff standard conversion sequence ICS1 is a proper
5387 subsequence of ICS2. */
5390 is_subseq (conversion *ics1, conversion *ics2)
5392 /* We can assume that a conversion of the same code
5393 between the same types indicates a subsequence since we only get
5394 here if the types we are converting from are the same. */
5396 while (ics1->kind == ck_rvalue
5397 || ics1->kind == ck_lvalue)
5398 ics1 = ics1->u.next;
5402 while (ics2->kind == ck_rvalue
5403 || ics2->kind == ck_lvalue)
5404 ics2 = ics2->u.next;
5406 if (ics2->kind == ck_user
5407 || ics2->kind == ck_ambig
5408 || ics2->kind == ck_identity)
5409 /* At this point, ICS1 cannot be a proper subsequence of
5410 ICS2. We can get a USER_CONV when we are comparing the
5411 second standard conversion sequence of two user conversion
5415 ics2 = ics2->u.next;
5417 if (ics2->kind == ics1->kind
5418 && same_type_p (ics2->type, ics1->type)
5419 && same_type_p (ics2->u.next->type,
5420 ics1->u.next->type))
5425 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5426 be any _TYPE nodes. */
5429 is_properly_derived_from (tree derived, tree base)
5431 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5432 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5435 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5436 considers every class derived from itself. */
5437 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5438 && DERIVED_FROM_P (base, derived));
5441 /* We build the ICS for an implicit object parameter as a pointer
5442 conversion sequence. However, such a sequence should be compared
5443 as if it were a reference conversion sequence. If ICS is the
5444 implicit conversion sequence for an implicit object parameter,
5445 modify it accordingly. */
5448 maybe_handle_implicit_object (conversion **ics)
5452 /* [over.match.funcs]
5454 For non-static member functions, the type of the
5455 implicit object parameter is "reference to cv X"
5456 where X is the class of which the function is a
5457 member and cv is the cv-qualification on the member
5458 function declaration. */
5459 conversion *t = *ics;
5460 tree reference_type;
5462 /* The `this' parameter is a pointer to a class type. Make the
5463 implicit conversion talk about a reference to that same class
5465 reference_type = TREE_TYPE (t->type);
5466 reference_type = build_reference_type (reference_type);
5468 if (t->kind == ck_qual)
5470 if (t->kind == ck_ptr)
5472 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
5473 t = direct_reference_binding (reference_type, t);
5478 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5479 and return the type to which the reference refers. Otherwise,
5480 leave *ICS unchanged and return NULL_TREE. */
5483 maybe_handle_ref_bind (conversion **ics)
5485 if ((*ics)->kind == ck_ref_bind)
5487 conversion *old_ics = *ics;
5488 tree type = TREE_TYPE (old_ics->type);
5489 *ics = old_ics->u.next;
5490 (*ics)->user_conv_p = old_ics->user_conv_p;
5491 (*ics)->bad_p = old_ics->bad_p;
5498 /* Compare two implicit conversion sequences according to the rules set out in
5499 [over.ics.rank]. Return values:
5501 1: ics1 is better than ics2
5502 -1: ics2 is better than ics1
5503 0: ics1 and ics2 are indistinguishable */
5506 compare_ics (conversion *ics1, conversion *ics2)
5512 tree deref_from_type1 = NULL_TREE;
5513 tree deref_from_type2 = NULL_TREE;
5514 tree deref_to_type1 = NULL_TREE;
5515 tree deref_to_type2 = NULL_TREE;
5516 conversion_rank rank1, rank2;
5518 /* REF_BINDING is nonzero if the result of the conversion sequence
5519 is a reference type. In that case TARGET_TYPE is the
5520 type referred to by the reference. */
5524 /* Handle implicit object parameters. */
5525 maybe_handle_implicit_object (&ics1);
5526 maybe_handle_implicit_object (&ics2);
5528 /* Handle reference parameters. */
5529 target_type1 = maybe_handle_ref_bind (&ics1);
5530 target_type2 = maybe_handle_ref_bind (&ics2);
5534 When comparing the basic forms of implicit conversion sequences (as
5535 defined in _over.best.ics_)
5537 --a standard conversion sequence (_over.ics.scs_) is a better
5538 conversion sequence than a user-defined conversion sequence
5539 or an ellipsis conversion sequence, and
5541 --a user-defined conversion sequence (_over.ics.user_) is a
5542 better conversion sequence than an ellipsis conversion sequence
5543 (_over.ics.ellipsis_). */
5544 rank1 = CONVERSION_RANK (ics1);
5545 rank2 = CONVERSION_RANK (ics2);
5549 else if (rank1 < rank2)
5552 if (rank1 == cr_bad)
5554 /* XXX Isn't this an extension? */
5555 /* Both ICS are bad. We try to make a decision based on what
5556 would have happened if they'd been good. */
5557 if (ics1->user_conv_p > ics2->user_conv_p
5558 || ics1->rank > ics2->rank)
5560 else if (ics1->user_conv_p < ics2->user_conv_p
5561 || ics1->rank < ics2->rank)
5564 /* We couldn't make up our minds; try to figure it out below. */
5567 if (ics1->ellipsis_p)
5568 /* Both conversions are ellipsis conversions. */
5571 /* User-defined conversion sequence U1 is a better conversion sequence
5572 than another user-defined conversion sequence U2 if they contain the
5573 same user-defined conversion operator or constructor and if the sec-
5574 ond standard conversion sequence of U1 is better than the second
5575 standard conversion sequence of U2. */
5577 if (ics1->user_conv_p)
5582 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
5583 if (t1->kind == ck_ambig)
5585 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
5586 if (t2->kind == ck_ambig)
5589 if (t1->cand->fn != t2->cand->fn)
5592 /* We can just fall through here, after setting up
5593 FROM_TYPE1 and FROM_TYPE2. */
5594 from_type1 = t1->type;
5595 from_type2 = t2->type;
5602 /* We're dealing with two standard conversion sequences.
5606 Standard conversion sequence S1 is a better conversion
5607 sequence than standard conversion sequence S2 if
5609 --S1 is a proper subsequence of S2 (comparing the conversion
5610 sequences in the canonical form defined by _over.ics.scs_,
5611 excluding any Lvalue Transformation; the identity
5612 conversion sequence is considered to be a subsequence of
5613 any non-identity conversion sequence */
5616 while (t1->kind != ck_identity)
5618 from_type1 = t1->type;
5621 while (t2->kind != ck_identity)
5623 from_type2 = t2->type;
5626 if (same_type_p (from_type1, from_type2))
5628 if (is_subseq (ics1, ics2))
5630 if (is_subseq (ics2, ics1))
5633 /* Otherwise, one sequence cannot be a subsequence of the other; they
5634 don't start with the same type. This can happen when comparing the
5635 second standard conversion sequence in two user-defined conversion
5642 --the rank of S1 is better than the rank of S2 (by the rules
5645 Standard conversion sequences are ordered by their ranks: an Exact
5646 Match is a better conversion than a Promotion, which is a better
5647 conversion than a Conversion.
5649 Two conversion sequences with the same rank are indistinguishable
5650 unless one of the following rules applies:
5652 --A conversion that is not a conversion of a pointer, or pointer
5653 to member, to bool is better than another conversion that is such
5656 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5657 so that we do not have to check it explicitly. */
5658 if (ics1->rank < ics2->rank)
5660 else if (ics2->rank < ics1->rank)
5663 to_type1 = ics1->type;
5664 to_type2 = ics2->type;
5666 if (TYPE_PTR_P (from_type1)
5667 && TYPE_PTR_P (from_type2)
5668 && TYPE_PTR_P (to_type1)
5669 && TYPE_PTR_P (to_type2))
5671 deref_from_type1 = TREE_TYPE (from_type1);
5672 deref_from_type2 = TREE_TYPE (from_type2);
5673 deref_to_type1 = TREE_TYPE (to_type1);
5674 deref_to_type2 = TREE_TYPE (to_type2);
5676 /* The rules for pointers to members A::* are just like the rules
5677 for pointers A*, except opposite: if B is derived from A then
5678 A::* converts to B::*, not vice versa. For that reason, we
5679 switch the from_ and to_ variables here. */
5680 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5681 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5682 || (TYPE_PTRMEMFUNC_P (from_type1)
5683 && TYPE_PTRMEMFUNC_P (from_type2)
5684 && TYPE_PTRMEMFUNC_P (to_type1)
5685 && TYPE_PTRMEMFUNC_P (to_type2)))
5687 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5688 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5689 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5690 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5693 if (deref_from_type1 != NULL_TREE
5694 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5695 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5697 /* This was one of the pointer or pointer-like conversions.
5701 --If class B is derived directly or indirectly from class A,
5702 conversion of B* to A* is better than conversion of B* to
5703 void*, and conversion of A* to void* is better than
5704 conversion of B* to void*. */
5705 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5706 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5708 if (is_properly_derived_from (deref_from_type1,
5711 else if (is_properly_derived_from (deref_from_type2,
5715 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5716 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5718 if (same_type_p (deref_from_type1, deref_from_type2))
5720 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5722 if (is_properly_derived_from (deref_from_type1,
5726 /* We know that DEREF_TO_TYPE1 is `void' here. */
5727 else if (is_properly_derived_from (deref_from_type1,
5732 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5733 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5737 --If class B is derived directly or indirectly from class A
5738 and class C is derived directly or indirectly from B,
5740 --conversion of C* to B* is better than conversion of C* to
5743 --conversion of B* to A* is better than conversion of C* to
5745 if (same_type_p (deref_from_type1, deref_from_type2))
5747 if (is_properly_derived_from (deref_to_type1,
5750 else if (is_properly_derived_from (deref_to_type2,
5754 else if (same_type_p (deref_to_type1, deref_to_type2))
5756 if (is_properly_derived_from (deref_from_type2,
5759 else if (is_properly_derived_from (deref_from_type1,
5765 else if (CLASS_TYPE_P (non_reference (from_type1))
5766 && same_type_p (from_type1, from_type2))
5768 tree from = non_reference (from_type1);
5772 --binding of an expression of type C to a reference of type
5773 B& is better than binding an expression of type C to a
5774 reference of type A&
5776 --conversion of C to B is better than conversion of C to A, */
5777 if (is_properly_derived_from (from, to_type1)
5778 && is_properly_derived_from (from, to_type2))
5780 if (is_properly_derived_from (to_type1, to_type2))
5782 else if (is_properly_derived_from (to_type2, to_type1))
5786 else if (CLASS_TYPE_P (non_reference (to_type1))
5787 && same_type_p (to_type1, to_type2))
5789 tree to = non_reference (to_type1);
5793 --binding of an expression of type B to a reference of type
5794 A& is better than binding an expression of type C to a
5795 reference of type A&,
5797 --conversion of B to A is better than conversion of C to A */
5798 if (is_properly_derived_from (from_type1, to)
5799 && is_properly_derived_from (from_type2, to))
5801 if (is_properly_derived_from (from_type2, from_type1))
5803 else if (is_properly_derived_from (from_type1, from_type2))
5810 --S1 and S2 differ only in their qualification conversion and yield
5811 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5812 qualification signature of type T1 is a proper subset of the cv-
5813 qualification signature of type T2 */
5814 if (ics1->kind == ck_qual
5815 && ics2->kind == ck_qual
5816 && same_type_p (from_type1, from_type2))
5817 return comp_cv_qual_signature (to_type1, to_type2);
5821 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5822 types to which the references refer are the same type except for
5823 top-level cv-qualifiers, and the type to which the reference
5824 initialized by S2 refers is more cv-qualified than the type to
5825 which the reference initialized by S1 refers */
5827 if (target_type1 && target_type2
5828 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5829 return comp_cv_qualification (target_type2, target_type1);
5831 /* Neither conversion sequence is better than the other. */
5835 /* The source type for this standard conversion sequence. */
5838 source_type (conversion *t)
5840 for (;; t = t->u.next)
5842 if (t->kind == ck_user
5843 || t->kind == ck_ambig
5844 || t->kind == ck_identity)
5850 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5851 a pointer to LOSER and re-running joust to produce the warning if WINNER
5852 is actually used. */
5855 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5857 candidate_warning *cw;
5859 cw = conversion_obstack_alloc (sizeof (candidate_warning));
5861 cw->next = winner->warnings;
5862 winner->warnings = cw;
5865 /* Compare two candidates for overloading as described in
5866 [over.match.best]. Return values:
5868 1: cand1 is better than cand2
5869 -1: cand2 is better than cand1
5870 0: cand1 and cand2 are indistinguishable */
5873 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5876 int off1 = 0, off2 = 0;
5880 /* Candidates that involve bad conversions are always worse than those
5882 if (cand1->viable > cand2->viable)
5884 if (cand1->viable < cand2->viable)
5887 /* If we have two pseudo-candidates for conversions to the same type,
5888 or two candidates for the same function, arbitrarily pick one. */
5889 if (cand1->fn == cand2->fn
5890 && (TYPE_P (cand1->fn) || DECL_P (cand1->fn)))
5893 /* a viable function F1
5894 is defined to be a better function than another viable function F2 if
5895 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5896 ICSi(F2), and then */
5898 /* for some argument j, ICSj(F1) is a better conversion sequence than
5901 /* For comparing static and non-static member functions, we ignore
5902 the implicit object parameter of the non-static function. The
5903 standard says to pretend that the static function has an object
5904 parm, but that won't work with operator overloading. */
5905 len = cand1->num_convs;
5906 if (len != cand2->num_convs)
5908 if (DECL_STATIC_FUNCTION_P (cand1->fn)
5909 && ! DECL_STATIC_FUNCTION_P (cand2->fn))
5911 else if (! DECL_STATIC_FUNCTION_P (cand1->fn)
5912 && DECL_STATIC_FUNCTION_P (cand2->fn))
5921 for (i = 0; i < len; ++i)
5923 conversion *t1 = cand1->convs[i + off1];
5924 conversion *t2 = cand2->convs[i + off2];
5925 int comp = compare_ics (t1, t2);
5930 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
5931 == cr_std + cr_promotion)
5932 && t1->kind == ck_std
5933 && t2->kind == ck_std
5934 && TREE_CODE (t1->type) == INTEGER_TYPE
5935 && TREE_CODE (t2->type) == INTEGER_TYPE
5936 && (TYPE_PRECISION (t1->type)
5937 == TYPE_PRECISION (t2->type))
5938 && (TYPE_UNSIGNED (t1->u.next->type)
5939 || (TREE_CODE (t1->u.next->type)
5942 tree type = t1->u.next->type;
5944 struct z_candidate *w, *l;
5946 type1 = t1->type, type2 = t2->type,
5947 w = cand1, l = cand2;
5949 type1 = t2->type, type2 = t1->type,
5950 w = cand2, l = cand1;
5954 warning ("passing `%T' chooses `%T' over `%T'",
5955 type, type1, type2);
5956 warning (" in call to `%D'", w->fn);
5962 if (winner && comp != winner)
5971 /* warn about confusing overload resolution for user-defined conversions,
5972 either between a constructor and a conversion op, or between two
5974 if (winner && warn_conversion && cand1->second_conv
5975 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
5976 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
5978 struct z_candidate *w, *l;
5979 bool give_warning = false;
5982 w = cand1, l = cand2;
5984 w = cand2, l = cand1;
5986 /* We don't want to complain about `X::operator T1 ()'
5987 beating `X::operator T2 () const', when T2 is a no less
5988 cv-qualified version of T1. */
5989 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
5990 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
5992 tree t = TREE_TYPE (TREE_TYPE (l->fn));
5993 tree f = TREE_TYPE (TREE_TYPE (w->fn));
5995 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
6000 if (!comp_ptr_ttypes (t, f))
6001 give_warning = true;
6004 give_warning = true;
6010 tree source = source_type (w->convs[0]);
6011 if (! DECL_CONSTRUCTOR_P (w->fn))
6012 source = TREE_TYPE (source);
6013 warning ("choosing `%D' over `%D'", w->fn, l->fn);
6014 warning (" for conversion from `%T' to `%T'",
6015 source, w->second_conv->type);
6016 warning (" because conversion sequence for the argument is better");
6026 F1 is a non-template function and F2 is a template function
6029 if (!cand1->template_decl && cand2->template_decl)
6031 else if (cand1->template_decl && !cand2->template_decl)
6035 F1 and F2 are template functions and the function template for F1 is
6036 more specialized than the template for F2 according to the partial
6039 if (cand1->template_decl && cand2->template_decl)
6041 winner = more_specialized
6042 (TI_TEMPLATE (cand1->template_decl),
6043 TI_TEMPLATE (cand2->template_decl),
6045 /* Tell the deduction code how many real function arguments
6046 we saw, not counting the implicit 'this' argument. But,
6047 add_function_candidate() suppresses the "this" argument
6050 [temp.func.order]: The presence of unused ellipsis and default
6051 arguments has no effect on the partial ordering of function
6054 - (DECL_NONSTATIC_MEMBER_FUNCTION_P (cand1->fn)
6055 - DECL_CONSTRUCTOR_P (cand1->fn)));
6061 the context is an initialization by user-defined conversion (see
6062 _dcl.init_ and _over.match.user_) and the standard conversion
6063 sequence from the return type of F1 to the destination type (i.e.,
6064 the type of the entity being initialized) is a better conversion
6065 sequence than the standard conversion sequence from the return type
6066 of F2 to the destination type. */
6068 if (cand1->second_conv)
6070 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6075 /* Check whether we can discard a builtin candidate, either because we
6076 have two identical ones or matching builtin and non-builtin candidates.
6078 (Pedantically in the latter case the builtin which matched the user
6079 function should not be added to the overload set, but we spot it here.
6082 ... the builtin candidates include ...
6083 - do not have the same parameter type list as any non-template
6084 non-member candidate. */
6086 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6087 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6089 for (i = 0; i < len; ++i)
6090 if (!same_type_p (cand1->convs[i]->type,
6091 cand2->convs[i]->type))
6093 if (i == cand1->num_convs)
6095 if (cand1->fn == cand2->fn)
6096 /* Two built-in candidates; arbitrarily pick one. */
6098 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6099 /* cand1 is built-in; prefer cand2. */
6102 /* cand2 is built-in; prefer cand1. */
6107 /* If the two functions are the same (this can happen with declarations
6108 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6109 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6110 && equal_functions (cand1->fn, cand2->fn))
6115 /* Extension: If the worst conversion for one candidate is worse than the
6116 worst conversion for the other, take the first. */
6119 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6120 struct z_candidate *w = 0, *l = 0;
6122 for (i = 0; i < len; ++i)
6124 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6125 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6126 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6127 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6130 winner = 1, w = cand1, l = cand2;
6132 winner = -1, w = cand2, l = cand1;
6138 ISO C++ says that these are ambiguous, even \
6139 though the worst conversion for the first is better than \
6140 the worst conversion for the second:");
6141 print_z_candidate (_("candidate 1:"), w);
6142 print_z_candidate (_("candidate 2:"), l);
6150 my_friendly_assert (!winner, 20010121);
6154 /* Given a list of candidates for overloading, find the best one, if any.
6155 This algorithm has a worst case of O(2n) (winner is last), and a best
6156 case of O(n/2) (totally ambiguous); much better than a sorting
6159 static struct z_candidate *
6160 tourney (struct z_candidate *candidates)
6162 struct z_candidate *champ = candidates, *challenger;
6164 int champ_compared_to_predecessor = 0;
6166 /* Walk through the list once, comparing each current champ to the next
6167 candidate, knocking out a candidate or two with each comparison. */
6169 for (challenger = champ->next; challenger; )
6171 fate = joust (champ, challenger, 0);
6173 challenger = challenger->next;
6178 champ = challenger->next;
6181 champ_compared_to_predecessor = 0;
6186 champ_compared_to_predecessor = 1;
6189 challenger = champ->next;
6193 /* Make sure the champ is better than all the candidates it hasn't yet
6194 been compared to. */
6196 for (challenger = candidates;
6198 && !(champ_compared_to_predecessor && challenger->next == champ);
6199 challenger = challenger->next)
6201 fate = joust (champ, challenger, 0);
6209 /* Returns nonzero if things of type FROM can be converted to TO. */
6212 can_convert (tree to, tree from)
6214 return can_convert_arg (to, from, NULL_TREE);
6217 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6220 can_convert_arg (tree to, tree from, tree arg)
6226 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6227 p = conversion_obstack_alloc (0);
6229 t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
6230 ok_p = (t && !t->bad_p);
6232 /* Free all the conversions we allocated. */
6233 obstack_free (&conversion_obstack, p);
6238 /* Like can_convert_arg, but allows dubious conversions as well. */
6241 can_convert_arg_bad (tree to, tree from, tree arg)
6246 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6247 p = conversion_obstack_alloc (0);
6248 /* Try to perform the conversion. */
6249 t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
6250 /* Free all the conversions we allocated. */
6251 obstack_free (&conversion_obstack, p);
6256 /* Convert EXPR to TYPE. Return the converted expression.
6258 Note that we allow bad conversions here because by the time we get to
6259 this point we are committed to doing the conversion. If we end up
6260 doing a bad conversion, convert_like will complain. */
6263 perform_implicit_conversion (tree type, tree expr)
6268 if (error_operand_p (expr))
6269 return error_mark_node;
6271 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6272 p = conversion_obstack_alloc (0);
6274 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6278 error ("could not convert `%E' to `%T'", expr, type);
6279 expr = error_mark_node;
6282 expr = convert_like (conv, expr);
6284 /* Free all the conversions we allocated. */
6285 obstack_free (&conversion_obstack, p);
6290 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6291 permitted. If the conversion is valid, the converted expression is
6292 returned. Otherwise, NULL_TREE is returned, except in the case
6293 that TYPE is a class type; in that case, an error is issued. */
6296 perform_direct_initialization_if_possible (tree type, tree expr)
6301 if (type == error_mark_node || error_operand_p (expr))
6302 return error_mark_node;
6305 If the destination type is a (possibly cv-qualified) class type:
6307 -- If the initialization is direct-initialization ...,
6308 constructors are considered. ... If no constructor applies, or
6309 the overload resolution is ambiguous, the initialization is
6311 if (CLASS_TYPE_P (type))
6313 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6314 build_tree_list (NULL_TREE, expr),
6315 type, LOOKUP_NORMAL);
6316 return build_cplus_new (type, expr);
6319 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6320 p = conversion_obstack_alloc (0);
6322 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6324 if (!conv || conv->bad_p)
6327 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6328 /*issue_conversion_warnings=*/false);
6330 /* Free all the conversions we allocated. */
6331 obstack_free (&conversion_obstack, p);
6336 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6337 is being bound to a temporary. Create and return a new VAR_DECL
6338 with the indicated TYPE; this variable will store the value to
6339 which the reference is bound. */
6342 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6346 /* Create the variable. */
6347 var = build_decl (VAR_DECL, NULL_TREE, type);
6348 DECL_ARTIFICIAL (var) = 1;
6349 TREE_USED (var) = 1;
6351 /* Register the variable. */
6352 if (TREE_STATIC (decl))
6354 /* Namespace-scope or local static; give it a mangled name. */
6357 TREE_STATIC (var) = 1;
6358 name = mangle_ref_init_variable (decl);
6359 DECL_NAME (var) = name;
6360 SET_DECL_ASSEMBLER_NAME (var, name);
6361 var = pushdecl_top_level (var);
6365 /* Create a new cleanup level if necessary. */
6366 maybe_push_cleanup_level (type);
6367 /* Don't push unnamed temps. Do set DECL_CONTEXT, though. */
6368 DECL_CONTEXT (var) = current_function_decl;
6374 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6375 initializing a variable of that TYPE. If DECL is non-NULL, it is
6376 the VAR_DECL being initialized with the EXPR. (In that case, the
6377 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6378 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6379 return, if *CLEANUP is no longer NULL, it will be an expression
6380 that should be pushed as a cleanup after the returned expression
6381 is used to initialize DECL.
6383 Return the converted expression. */
6386 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6391 if (type == error_mark_node || error_operand_p (expr))
6392 return error_mark_node;
6394 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6395 p = conversion_obstack_alloc (0);
6397 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6398 if (!conv || conv->bad_p)
6400 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6401 && !real_lvalue_p (expr))
6402 error ("invalid initialization of non-const reference of "
6403 "type '%T' from a temporary of type '%T'",
6404 type, TREE_TYPE (expr));
6406 error ("invalid initialization of reference of type "
6407 "'%T' from expression of type '%T'", type,
6409 return error_mark_node;
6412 /* If DECL is non-NULL, then this special rule applies:
6416 The temporary to which the reference is bound or the temporary
6417 that is the complete object to which the reference is bound
6418 persists for the lifetime of the reference.
6420 The temporaries created during the evaluation of the expression
6421 initializing the reference, except the temporary to which the
6422 reference is bound, are destroyed at the end of the
6423 full-expression in which they are created.
6425 In that case, we store the converted expression into a new
6426 VAR_DECL in a new scope.
6428 However, we want to be careful not to create temporaries when
6429 they are not required. For example, given:
6432 struct D : public B {};
6436 there is no need to copy the return value from "f"; we can just
6437 extend its lifetime. Similarly, given:
6440 struct T { operator S(); };
6444 we can extend the lifetime of the return value of the conversion
6446 my_friendly_assert (conv->kind == ck_ref_bind, 20030302);
6450 tree base_conv_type;
6452 /* Skip over the REF_BIND. */
6453 conv = conv->u.next;
6454 /* If the next conversion is a BASE_CONV, skip that too -- but
6455 remember that the conversion was required. */
6456 if (conv->kind == ck_base && conv->need_temporary_p)
6458 if (conv->check_copy_constructor_p)
6459 check_constructor_callable (TREE_TYPE (expr), expr);
6460 base_conv_type = conv->type;
6461 conv = conv->u.next;
6464 base_conv_type = NULL_TREE;
6465 /* Perform the remainder of the conversion. */
6466 expr = convert_like_real (conv, expr,
6467 /*fn=*/NULL_TREE, /*argnum=*/0,
6469 /*issue_conversion_warnings=*/true);
6470 if (!real_lvalue_p (expr))
6475 /* Create the temporary variable. */
6476 type = TREE_TYPE (expr);
6477 var = make_temporary_var_for_ref_to_temp (decl, type);
6478 layout_decl (var, 0);
6479 /* If the rvalue is the result of a function call it will be
6480 a TARGET_EXPR. If it is some other construct (such as a
6481 member access expression where the underlying object is
6482 itself the result of a function call), turn it into a
6483 TARGET_EXPR here. It is important that EXPR be a
6484 TARGET_EXPR below since otherwise the INIT_EXPR will
6485 attempt to make a bitwise copy of EXPR to initialize
6487 if (TREE_CODE (expr) != TARGET_EXPR)
6488 expr = get_target_expr (expr);
6489 /* Create the INIT_EXPR that will initialize the temporary
6491 init = build2 (INIT_EXPR, type, var, expr);
6492 if (at_function_scope_p ())
6494 add_decl_expr (var);
6495 *cleanup = cxx_maybe_build_cleanup (var);
6497 /* We must be careful to destroy the temporary only
6498 after its initialization has taken place. If the
6499 initialization throws an exception, then the
6500 destructor should not be run. We cannot simply
6501 transform INIT into something like:
6503 (INIT, ({ CLEANUP_STMT; }))
6505 because emit_local_var always treats the
6506 initializer as a full-expression. Thus, the
6507 destructor would run too early; it would run at the
6508 end of initializing the reference variable, rather
6509 than at the end of the block enclosing the
6512 The solution is to pass back a cleanup expression
6513 which the caller is responsible for attaching to
6514 the statement tree. */
6518 rest_of_decl_compilation (var, /*toplev=*/1, at_eof);
6519 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6520 static_aggregates = tree_cons (NULL_TREE, var,
6523 /* Use its address to initialize the reference variable. */
6524 expr = build_address (var);
6525 expr = build2 (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6528 /* Take the address of EXPR. */
6529 expr = build_unary_op (ADDR_EXPR, expr, 0);
6530 /* If a BASE_CONV was required, perform it now. */
6532 expr = (perform_implicit_conversion
6533 (build_pointer_type (base_conv_type), expr));
6534 expr = build_nop (type, expr);
6537 /* Perform the conversion. */
6538 expr = convert_like (conv, expr);
6540 /* Free all the conversions we allocated. */
6541 obstack_free (&conversion_obstack, p);
6546 #include "gt-cp-call.h"