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 build (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 = build (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
347 TREE_VALUE (tmp) = build (COMPOUND_EXPR, TREE_TYPE (t),
348 TREE_VALUE (tmp), t);
351 function = build (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;
433 null_ptr_cst_p (tree t)
437 A null pointer constant is an integral constant expression
438 (_expr.const_) rvalue of integer type that evaluates to zero. */
440 || (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
446 /* Returns nonzero if PARMLIST consists of only default parms and/or
450 sufficient_parms_p (tree parmlist)
452 for (; parmlist && parmlist != void_list_node;
453 parmlist = TREE_CHAIN (parmlist))
454 if (!TREE_PURPOSE (parmlist))
459 /* Allocate N bytes of memory from the conversion obstack. The memory
460 is zeroed before being returned. */
463 conversion_obstack_alloc (size_t n)
466 if (!conversion_obstack_initialized)
468 gcc_obstack_init (&conversion_obstack);
469 conversion_obstack_initialized = true;
471 p = obstack_alloc (&conversion_obstack, n);
476 /* Dynamically allocate a conversion. */
479 alloc_conversion (conversion_kind kind)
482 c = conversion_obstack_alloc (sizeof (conversion));
487 #ifdef ENABLE_CHECKING
489 /* Make sure that all memory on the conversion obstack has been
493 validate_conversion_obstack (void)
495 if (conversion_obstack_initialized)
496 my_friendly_assert ((obstack_next_free (&conversion_obstack)
497 == obstack_base (&conversion_obstack)),
501 #endif /* ENABLE_CHECKING */
503 /* Dynamically allocate an array of N conversions. */
506 alloc_conversions (size_t n)
508 return conversion_obstack_alloc (n * sizeof (conversion *));
512 build_conv (conversion_kind code, tree type, conversion *from)
515 conversion_rank rank = CONVERSION_RANK (from);
517 /* We can't use buildl1 here because CODE could be USER_CONV, which
518 takes two arguments. In that case, the caller is responsible for
519 filling in the second argument. */
520 t = alloc_conversion (code);
543 t->user_conv_p = (code == ck_user || from->user_conv_p);
544 t->bad_p = from->bad_p;
548 /* Build a representation of the identity conversion from EXPR to
549 itself. The TYPE should match the the type of EXPR, if EXPR is
553 build_identity_conv (tree type, tree expr)
557 c = alloc_conversion (ck_identity);
564 /* Converting from EXPR to TYPE was ambiguous in the sense that there
565 were multiple user-defined conversions to accomplish the job.
566 Build a conversion that indicates that ambiguity. */
569 build_ambiguous_conv (tree type, tree expr)
573 c = alloc_conversion (ck_ambig);
581 strip_top_quals (tree t)
583 if (TREE_CODE (t) == ARRAY_TYPE)
585 return cp_build_qualified_type (t, 0);
588 /* Returns the standard conversion path (see [conv]) from type FROM to type
589 TO, if any. For proper handling of null pointer constants, you must
590 also pass the expression EXPR to convert from. */
593 standard_conversion (tree to, tree from, tree expr)
595 enum tree_code fcode, tcode;
597 bool fromref = false;
599 to = non_reference (to);
600 if (TREE_CODE (from) == REFERENCE_TYPE)
603 from = TREE_TYPE (from);
605 to = strip_top_quals (to);
606 from = strip_top_quals (from);
608 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
609 && expr && type_unknown_p (expr))
611 expr = instantiate_type (to, expr, tf_conv);
612 if (expr == error_mark_node)
614 from = TREE_TYPE (expr);
617 fcode = TREE_CODE (from);
618 tcode = TREE_CODE (to);
620 conv = build_identity_conv (from, expr);
621 if (fcode == FUNCTION_TYPE)
623 from = build_pointer_type (from);
624 fcode = TREE_CODE (from);
625 conv = build_conv (ck_lvalue, from, conv);
627 else if (fcode == ARRAY_TYPE)
629 from = build_pointer_type (TREE_TYPE (from));
630 fcode = TREE_CODE (from);
631 conv = build_conv (ck_lvalue, from, conv);
633 else if (fromref || (expr && lvalue_p (expr)))
634 conv = build_conv (ck_rvalue, from, conv);
636 /* Allow conversion between `__complex__' data types. */
637 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
639 /* The standard conversion sequence to convert FROM to TO is
640 the standard conversion sequence to perform componentwise
642 conversion *part_conv = standard_conversion
643 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE);
647 conv = build_conv (part_conv->kind, to, conv);
648 conv->rank = part_conv->rank;
656 if (same_type_p (from, to))
659 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
660 && expr && null_ptr_cst_p (expr))
661 conv = build_conv (ck_std, to, conv);
662 else if (tcode == POINTER_TYPE && fcode == POINTER_TYPE
663 && TREE_CODE (TREE_TYPE (to)) == VECTOR_TYPE
664 && TREE_CODE (TREE_TYPE (from)) == VECTOR_TYPE
665 && vector_types_convertible_p (TREE_TYPE (to), TREE_TYPE (from)))
666 conv = build_conv (ck_std, to, conv);
667 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
668 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
670 /* For backwards brain damage compatibility, allow interconversion of
671 pointers and integers with a pedwarn. */
672 conv = build_conv (ck_std, to, conv);
675 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
677 /* For backwards brain damage compatibility, allow interconversion of
678 enums and integers with a pedwarn. */
679 conv = build_conv (ck_std, to, conv);
682 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
683 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
688 if (tcode == POINTER_TYPE
689 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
692 else if (VOID_TYPE_P (TREE_TYPE (to))
693 && !TYPE_PTRMEM_P (from)
694 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
696 from = build_pointer_type
697 (cp_build_qualified_type (void_type_node,
698 cp_type_quals (TREE_TYPE (from))));
699 conv = build_conv (ck_ptr, from, conv);
701 else if (TYPE_PTRMEM_P (from))
703 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
704 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
706 if (DERIVED_FROM_P (fbase, tbase)
707 && (same_type_ignoring_top_level_qualifiers_p
708 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
709 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
711 from = build_ptrmem_type (tbase,
712 TYPE_PTRMEM_POINTED_TO_TYPE (from));
713 conv = build_conv (ck_pmem, from, conv);
716 else if (IS_AGGR_TYPE (TREE_TYPE (from))
717 && IS_AGGR_TYPE (TREE_TYPE (to))
720 An rvalue of type "pointer to cv D," where D is a
721 class type, can be converted to an rvalue of type
722 "pointer to cv B," where B is a base class (clause
723 _class.derived_) of D. If B is an inaccessible
724 (clause _class.access_) or ambiguous
725 (_class.member.lookup_) base class of D, a program
726 that necessitates this conversion is ill-formed. */
727 /* Therefore, we use DERIVED_FROM_P, and not
728 ACCESSIBLY_UNIQUELY_DERIVED_FROM_P, in this test. */
729 && DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
732 cp_build_qualified_type (TREE_TYPE (to),
733 cp_type_quals (TREE_TYPE (from)));
734 from = build_pointer_type (from);
735 conv = build_conv (ck_ptr, from, conv);
738 if (tcode == POINTER_TYPE)
740 to_pointee = TREE_TYPE (to);
741 from_pointee = TREE_TYPE (from);
745 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
746 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
749 if (same_type_p (from, to))
751 else if (comp_ptr_ttypes (to_pointee, from_pointee))
752 conv = build_conv (ck_qual, to, conv);
753 else if (expr && string_conv_p (to, expr, 0))
754 /* converting from string constant to char *. */
755 conv = build_conv (ck_qual, to, conv);
756 else if (ptr_reasonably_similar (to_pointee, from_pointee))
758 conv = build_conv (ck_ptr, to, conv);
766 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
768 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
769 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
770 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
771 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
773 if (!DERIVED_FROM_P (fbase, tbase)
774 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
775 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
776 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
777 || cp_type_quals (fbase) != cp_type_quals (tbase))
780 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
781 from = build_method_type_directly (from,
783 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
784 from = build_ptrmemfunc_type (build_pointer_type (from));
785 conv = build_conv (ck_pmem, from, conv);
787 else if (tcode == BOOLEAN_TYPE)
791 An rvalue of arithmetic, enumeration, pointer, or pointer to
792 member type can be converted to an rvalue of type bool. */
793 if (ARITHMETIC_TYPE_P (from)
794 || fcode == ENUMERAL_TYPE
795 || fcode == POINTER_TYPE
796 || TYPE_PTR_TO_MEMBER_P (from))
798 conv = build_conv (ck_std, to, conv);
799 if (fcode == POINTER_TYPE
800 || TYPE_PTRMEM_P (from)
801 || (TYPE_PTRMEMFUNC_P (from)
802 && conv->rank < cr_pbool))
803 conv->rank = cr_pbool;
809 /* We don't check for ENUMERAL_TYPE here because there are no standard
810 conversions to enum type. */
811 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
812 || tcode == REAL_TYPE)
814 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
816 conv = build_conv (ck_std, to, conv);
818 /* Give this a better rank if it's a promotion. */
819 if (same_type_p (to, type_promotes_to (from))
820 && conv->u.next->rank <= cr_promotion)
821 conv->rank = cr_promotion;
823 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
824 && vector_types_convertible_p (from, to))
825 return build_conv (ck_std, to, conv);
826 else if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
827 && is_properly_derived_from (from, to))
829 if (conv->kind == ck_rvalue)
831 conv = build_conv (ck_base, to, conv);
832 /* The derived-to-base conversion indicates the initialization
833 of a parameter with base type from an object of a derived
834 type. A temporary object is created to hold the result of
836 conv->need_temporary_p = true;
844 /* Returns nonzero if T1 is reference-related to T2. */
847 reference_related_p (tree t1, tree t2)
849 t1 = TYPE_MAIN_VARIANT (t1);
850 t2 = TYPE_MAIN_VARIANT (t2);
854 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
855 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
857 return (same_type_p (t1, t2)
858 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
859 && DERIVED_FROM_P (t1, t2)));
862 /* Returns nonzero if T1 is reference-compatible with T2. */
865 reference_compatible_p (tree t1, tree t2)
869 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
870 reference-related to T2 and cv1 is the same cv-qualification as,
871 or greater cv-qualification than, cv2. */
872 return (reference_related_p (t1, t2)
873 && at_least_as_qualified_p (t1, t2));
876 /* Determine whether or not the EXPR (of class type S) can be
877 converted to T as in [over.match.ref]. */
880 convert_class_to_reference (tree t, tree s, tree expr)
886 struct z_candidate *candidates;
887 struct z_candidate *cand;
890 conversions = lookup_conversions (s);
896 Assuming that "cv1 T" is the underlying type of the reference
897 being initialized, and "cv S" is the type of the initializer
898 expression, with S a class type, the candidate functions are
901 --The conversion functions of S and its base classes are
902 considered. Those that are not hidden within S and yield type
903 "reference to cv2 T2", where "cv1 T" is reference-compatible
904 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
906 The argument list has one argument, which is the initializer
911 /* Conceptually, we should take the address of EXPR and put it in
912 the argument list. Unfortunately, however, that can result in
913 error messages, which we should not issue now because we are just
914 trying to find a conversion operator. Therefore, we use NULL,
915 cast to the appropriate type. */
916 arglist = build_int_2 (0, 0);
917 TREE_TYPE (arglist) = build_pointer_type (s);
918 arglist = build_tree_list (NULL_TREE, arglist);
920 reference_type = build_reference_type (t);
924 tree fns = TREE_VALUE (conversions);
926 for (; fns; fns = OVL_NEXT (fns))
928 tree f = OVL_CURRENT (fns);
929 tree t2 = TREE_TYPE (TREE_TYPE (f));
933 /* If this is a template function, try to get an exact
935 if (TREE_CODE (f) == TEMPLATE_DECL)
937 cand = add_template_candidate (&candidates,
943 TREE_PURPOSE (conversions),
949 /* Now, see if the conversion function really returns
950 an lvalue of the appropriate type. From the
951 point of view of unification, simply returning an
952 rvalue of the right type is good enough. */
954 t2 = TREE_TYPE (TREE_TYPE (f));
955 if (TREE_CODE (t2) != REFERENCE_TYPE
956 || !reference_compatible_p (t, TREE_TYPE (t2)))
958 candidates = candidates->next;
963 else if (TREE_CODE (t2) == REFERENCE_TYPE
964 && reference_compatible_p (t, TREE_TYPE (t2)))
965 cand = add_function_candidate (&candidates, f, s, arglist,
967 TREE_PURPOSE (conversions),
972 conversion *identity_conv;
973 /* Build a standard conversion sequence indicating the
974 binding from the reference type returned by the
975 function to the desired REFERENCE_TYPE. */
977 = build_identity_conv (TREE_TYPE (TREE_TYPE
978 (TREE_TYPE (cand->fn))),
981 = (direct_reference_binding
982 (reference_type, identity_conv));
983 cand->second_conv->bad_p |= cand->convs[0]->bad_p;
986 conversions = TREE_CHAIN (conversions);
989 candidates = splice_viable (candidates, pedantic, &any_viable_p);
990 /* If none of the conversion functions worked out, let our caller
995 cand = tourney (candidates);
999 /* Now that we know that this is the function we're going to use fix
1000 the dummy first argument. */
1001 cand->args = tree_cons (NULL_TREE,
1003 TREE_CHAIN (cand->args));
1005 /* Build a user-defined conversion sequence representing the
1007 conv = build_conv (ck_user,
1008 TREE_TYPE (TREE_TYPE (cand->fn)),
1009 build_identity_conv (TREE_TYPE (expr), expr));
1012 /* Merge it with the standard conversion sequence from the
1013 conversion function's return type to the desired type. */
1014 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
1016 if (cand->viable == -1)
1019 return cand->second_conv;
1022 /* A reference of the indicated TYPE is being bound directly to the
1023 expression represented by the implicit conversion sequence CONV.
1024 Return a conversion sequence for this binding. */
1027 direct_reference_binding (tree type, conversion *conv)
1031 my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 20030306);
1032 my_friendly_assert (TREE_CODE (conv->type) != REFERENCE_TYPE, 20030306);
1034 t = TREE_TYPE (type);
1038 When a parameter of reference type binds directly
1039 (_dcl.init.ref_) to an argument expression, the implicit
1040 conversion sequence is the identity conversion, unless the
1041 argument expression has a type that is a derived class of the
1042 parameter type, in which case the implicit conversion sequence is
1043 a derived-to-base Conversion.
1045 If the parameter binds directly to the result of applying a
1046 conversion function to the argument expression, the implicit
1047 conversion sequence is a user-defined conversion sequence
1048 (_over.ics.user_), with the second standard conversion sequence
1049 either an identity conversion or, if the conversion function
1050 returns an entity of a type that is a derived class of the
1051 parameter type, a derived-to-base conversion. */
1052 if (!same_type_ignoring_top_level_qualifiers_p (t, conv->type))
1054 /* Represent the derived-to-base conversion. */
1055 conv = build_conv (ck_base, t, conv);
1056 /* We will actually be binding to the base-class subobject in
1057 the derived class, so we mark this conversion appropriately.
1058 That way, convert_like knows not to generate a temporary. */
1059 conv->need_temporary_p = false;
1061 return build_conv (ck_ref_bind, type, conv);
1064 /* Returns the conversion path from type FROM to reference type TO for
1065 purposes of reference binding. For lvalue binding, either pass a
1066 reference type to FROM or an lvalue expression to EXPR. If the
1067 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1068 the conversion returned. */
1071 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1073 conversion *conv = NULL;
1074 tree to = TREE_TYPE (rto);
1078 cp_lvalue_kind lvalue_p = clk_none;
1080 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1082 expr = instantiate_type (to, expr, tf_none);
1083 if (expr == error_mark_node)
1085 from = TREE_TYPE (expr);
1088 if (TREE_CODE (from) == REFERENCE_TYPE)
1090 /* Anything with reference type is an lvalue. */
1091 lvalue_p = clk_ordinary;
1092 from = TREE_TYPE (from);
1095 lvalue_p = real_lvalue_p (expr);
1097 /* Figure out whether or not the types are reference-related and
1098 reference compatible. We have do do this after stripping
1099 references from FROM. */
1100 related_p = reference_related_p (to, from);
1101 compatible_p = reference_compatible_p (to, from);
1103 if (lvalue_p && compatible_p)
1107 If the initializer expression
1109 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1110 is reference-compatible with "cv2 T2,"
1112 the reference is bound directly to the initializer expression
1114 conv = build_identity_conv (from, expr);
1115 conv = direct_reference_binding (rto, conv);
1116 if ((lvalue_p & clk_bitfield) != 0
1117 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1118 /* For the purposes of overload resolution, we ignore the fact
1119 this expression is a bitfield or packed field. (In particular,
1120 [over.ics.ref] says specifically that a function with a
1121 non-const reference parameter is viable even if the
1122 argument is a bitfield.)
1124 However, when we actually call the function we must create
1125 a temporary to which to bind the reference. If the
1126 reference is volatile, or isn't const, then we cannot make
1127 a temporary, so we just issue an error when the conversion
1129 conv->need_temporary_p = true;
1133 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1137 If the initializer expression
1139 -- has a class type (i.e., T2 is a class type) can be
1140 implicitly converted to an lvalue of type "cv3 T3," where
1141 "cv1 T1" is reference-compatible with "cv3 T3". (this
1142 conversion is selected by enumerating the applicable
1143 conversion functions (_over.match.ref_) and choosing the
1144 best one through overload resolution. (_over.match_).
1146 the reference is bound to the lvalue result of the conversion
1147 in the second case. */
1148 conv = convert_class_to_reference (to, from, expr);
1153 /* From this point on, we conceptually need temporaries, even if we
1154 elide them. Only the cases above are "direct bindings". */
1155 if (flags & LOOKUP_NO_TEMP_BIND)
1160 When a parameter of reference type is not bound directly to an
1161 argument expression, the conversion sequence is the one required
1162 to convert the argument expression to the underlying type of the
1163 reference according to _over.best.ics_. Conceptually, this
1164 conversion sequence corresponds to copy-initializing a temporary
1165 of the underlying type with the argument expression. Any
1166 difference in top-level cv-qualification is subsumed by the
1167 initialization itself and does not constitute a conversion. */
1171 Otherwise, the reference shall be to a non-volatile const type. */
1172 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1177 If the initializer expression is an rvalue, with T2 a class type,
1178 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1179 is bound in one of the following ways:
1181 -- The reference is bound to the object represented by the rvalue
1182 or to a sub-object within that object.
1186 We use the first alternative. The implicit conversion sequence
1187 is supposed to be same as we would obtain by generating a
1188 temporary. Fortunately, if the types are reference compatible,
1189 then this is either an identity conversion or the derived-to-base
1190 conversion, just as for direct binding. */
1191 if (CLASS_TYPE_P (from) && compatible_p)
1193 conv = build_identity_conv (from, expr);
1194 conv = direct_reference_binding (rto, conv);
1195 if (!(flags & LOOKUP_CONSTRUCTOR_CALLABLE))
1196 conv->u.next->check_copy_constructor_p = true;
1202 Otherwise, a temporary of type "cv1 T1" is created and
1203 initialized from the initializer expression using the rules for a
1204 non-reference copy initialization. If T1 is reference-related to
1205 T2, cv1 must be the same cv-qualification as, or greater
1206 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1207 if (related_p && !at_least_as_qualified_p (to, from))
1210 conv = implicit_conversion (to, from, expr, flags);
1214 conv = build_conv (ck_ref_bind, rto, conv);
1215 /* This reference binding, unlike those above, requires the
1216 creation of a temporary. */
1217 conv->need_temporary_p = true;
1222 /* Returns the implicit conversion sequence (see [over.ics]) from type FROM
1223 to type TO. The optional expression EXPR may affect the conversion.
1224 FLAGS are the usual overloading flags. Only LOOKUP_NO_CONVERSION is
1228 implicit_conversion (tree to, tree from, tree expr, int flags)
1232 if (from == error_mark_node || to == error_mark_node
1233 || expr == error_mark_node)
1236 if (TREE_CODE (to) == REFERENCE_TYPE)
1237 conv = reference_binding (to, from, expr, flags);
1239 conv = standard_conversion (to, from, expr);
1244 if (expr != NULL_TREE
1245 && (IS_AGGR_TYPE (from)
1246 || IS_AGGR_TYPE (to))
1247 && (flags & LOOKUP_NO_CONVERSION) == 0)
1249 struct z_candidate *cand;
1251 cand = build_user_type_conversion_1
1252 (to, expr, LOOKUP_ONLYCONVERTING);
1254 conv = cand->second_conv;
1256 /* We used to try to bind a reference to a temporary here, but that
1257 is now handled by the recursive call to this function at the end
1258 of reference_binding. */
1265 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1268 static struct z_candidate *
1269 add_candidate (struct z_candidate **candidates,
1271 size_t num_convs, conversion **convs,
1272 tree access_path, tree conversion_path,
1275 struct z_candidate *cand
1276 = conversion_obstack_alloc (sizeof (struct z_candidate));
1280 cand->convs = convs;
1281 cand->num_convs = num_convs;
1282 cand->access_path = access_path;
1283 cand->conversion_path = conversion_path;
1284 cand->viable = viable;
1285 cand->next = *candidates;
1291 /* Create an overload candidate for the function or method FN called with
1292 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1293 to implicit_conversion.
1295 CTYPE, if non-NULL, is the type we want to pretend this function
1296 comes from for purposes of overload resolution. */
1298 static struct z_candidate *
1299 add_function_candidate (struct z_candidate **candidates,
1300 tree fn, tree ctype, tree arglist,
1301 tree access_path, tree conversion_path,
1304 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1307 tree parmnode, argnode;
1311 /* Built-in functions that haven't been declared don't really
1313 if (DECL_ANTICIPATED (fn))
1316 /* The `this', `in_chrg' and VTT arguments to constructors are not
1317 considered in overload resolution. */
1318 if (DECL_CONSTRUCTOR_P (fn))
1320 parmlist = skip_artificial_parms_for (fn, parmlist);
1321 orig_arglist = arglist;
1322 arglist = skip_artificial_parms_for (fn, arglist);
1325 orig_arglist = arglist;
1327 len = list_length (arglist);
1328 convs = alloc_conversions (len);
1330 /* 13.3.2 - Viable functions [over.match.viable]
1331 First, to be a viable function, a candidate function shall have enough
1332 parameters to agree in number with the arguments in the list.
1334 We need to check this first; otherwise, checking the ICSes might cause
1335 us to produce an ill-formed template instantiation. */
1337 parmnode = parmlist;
1338 for (i = 0; i < len; ++i)
1340 if (parmnode == NULL_TREE || parmnode == void_list_node)
1342 parmnode = TREE_CHAIN (parmnode);
1345 if (i < len && parmnode)
1348 /* Make sure there are default args for the rest of the parms. */
1349 else if (!sufficient_parms_p (parmnode))
1355 /* Second, for F to be a viable function, there shall exist for each
1356 argument an implicit conversion sequence that converts that argument
1357 to the corresponding parameter of F. */
1359 parmnode = parmlist;
1362 for (i = 0; i < len; ++i)
1364 tree arg = TREE_VALUE (argnode);
1365 tree argtype = lvalue_type (arg);
1369 if (parmnode == void_list_node)
1372 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1373 && ! DECL_CONSTRUCTOR_P (fn));
1377 tree parmtype = TREE_VALUE (parmnode);
1379 /* The type of the implicit object parameter ('this') for
1380 overload resolution is not always the same as for the
1381 function itself; conversion functions are considered to
1382 be members of the class being converted, and functions
1383 introduced by a using-declaration are considered to be
1384 members of the class that uses them.
1386 Since build_over_call ignores the ICS for the `this'
1387 parameter, we can just change the parm type. */
1388 if (ctype && is_this)
1391 = build_qualified_type (ctype,
1392 TYPE_QUALS (TREE_TYPE (parmtype)));
1393 parmtype = build_pointer_type (parmtype);
1396 t = implicit_conversion (parmtype, argtype, arg, flags);
1400 t = build_identity_conv (argtype, arg);
1401 t->ellipsis_p = true;
1418 parmnode = TREE_CHAIN (parmnode);
1419 argnode = TREE_CHAIN (argnode);
1423 return add_candidate (candidates, fn, orig_arglist, len, convs,
1424 access_path, conversion_path, viable);
1427 /* Create an overload candidate for the conversion function FN which will
1428 be invoked for expression OBJ, producing a pointer-to-function which
1429 will in turn be called with the argument list ARGLIST, and add it to
1430 CANDIDATES. FLAGS is passed on to implicit_conversion.
1432 Actually, we don't really care about FN; we care about the type it
1433 converts to. There may be multiple conversion functions that will
1434 convert to that type, and we rely on build_user_type_conversion_1 to
1435 choose the best one; so when we create our candidate, we record the type
1436 instead of the function. */
1438 static struct z_candidate *
1439 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1440 tree arglist, tree access_path, tree conversion_path)
1442 tree totype = TREE_TYPE (TREE_TYPE (fn));
1443 int i, len, viable, flags;
1444 tree parmlist, parmnode, argnode;
1447 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1448 parmlist = TREE_TYPE (parmlist);
1449 parmlist = TYPE_ARG_TYPES (parmlist);
1451 len = list_length (arglist) + 1;
1452 convs = alloc_conversions (len);
1453 parmnode = parmlist;
1456 flags = LOOKUP_NORMAL;
1458 /* Don't bother looking up the same type twice. */
1459 if (*candidates && (*candidates)->fn == totype)
1462 for (i = 0; i < len; ++i)
1464 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1465 tree argtype = lvalue_type (arg);
1469 t = implicit_conversion (totype, argtype, arg, flags);
1470 else if (parmnode == void_list_node)
1473 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, flags);
1476 t = build_identity_conv (argtype, arg);
1477 t->ellipsis_p = true;
1491 parmnode = TREE_CHAIN (parmnode);
1492 argnode = TREE_CHAIN (argnode);
1498 if (!sufficient_parms_p (parmnode))
1501 return add_candidate (candidates, totype, arglist, len, convs,
1502 access_path, conversion_path, viable);
1506 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1507 tree type1, tree type2, tree *args, tree *argtypes,
1519 num_convs = args[2] ? 3 : (args[1] ? 2 : 1);
1520 convs = alloc_conversions (num_convs);
1522 for (i = 0; i < 2; ++i)
1527 t = implicit_conversion (types[i], argtypes[i], args[i], flags);
1531 /* We need something for printing the candidate. */
1532 t = build_identity_conv (types[i], NULL_TREE);
1539 /* For COND_EXPR we rearranged the arguments; undo that now. */
1542 convs[2] = convs[1];
1543 convs[1] = convs[0];
1544 t = implicit_conversion (boolean_type_node, argtypes[2], args[2], flags);
1551 add_candidate (candidates, fnname, /*args=*/NULL_TREE,
1553 /*access_path=*/NULL_TREE,
1554 /*conversion_path=*/NULL_TREE,
1559 is_complete (tree t)
1561 return COMPLETE_TYPE_P (complete_type (t));
1564 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1567 promoted_arithmetic_type_p (tree type)
1571 In this section, the term promoted integral type is used to refer
1572 to those integral types which are preserved by integral promotion
1573 (including e.g. int and long but excluding e.g. char).
1574 Similarly, the term promoted arithmetic type refers to promoted
1575 integral types plus floating types. */
1576 return ((INTEGRAL_TYPE_P (type)
1577 && same_type_p (type_promotes_to (type), type))
1578 || TREE_CODE (type) == REAL_TYPE);
1581 /* Create any builtin operator overload candidates for the operator in
1582 question given the converted operand types TYPE1 and TYPE2. The other
1583 args are passed through from add_builtin_candidates to
1584 build_builtin_candidate.
1586 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1587 If CODE is requires candidates operands of the same type of the kind
1588 of which TYPE1 and TYPE2 are, we add both candidates
1589 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1592 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1593 enum tree_code code2, tree fnname, tree type1,
1594 tree type2, tree *args, tree *argtypes, int flags)
1598 case POSTINCREMENT_EXPR:
1599 case POSTDECREMENT_EXPR:
1600 args[1] = integer_zero_node;
1601 type2 = integer_type_node;
1610 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1611 and VQ is either volatile or empty, there exist candidate operator
1612 functions of the form
1613 VQ T& operator++(VQ T&);
1614 T operator++(VQ T&, int);
1615 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1616 type other than bool, and VQ is either volatile or empty, there exist
1617 candidate operator functions of the form
1618 VQ T& operator--(VQ T&);
1619 T operator--(VQ T&, int);
1620 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1621 complete object type, and VQ is either volatile or empty, there exist
1622 candidate operator functions of the form
1623 T*VQ& operator++(T*VQ&);
1624 T*VQ& operator--(T*VQ&);
1625 T* operator++(T*VQ&, int);
1626 T* operator--(T*VQ&, int); */
1628 case POSTDECREMENT_EXPR:
1629 case PREDECREMENT_EXPR:
1630 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1632 case POSTINCREMENT_EXPR:
1633 case PREINCREMENT_EXPR:
1634 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1636 type1 = build_reference_type (type1);
1641 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1642 exist candidate operator functions of the form
1646 8 For every function type T, there exist candidate operator functions of
1648 T& operator*(T*); */
1651 if (TREE_CODE (type1) == POINTER_TYPE
1652 && (TYPE_PTROB_P (type1)
1653 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1657 /* 9 For every type T, there exist candidate operator functions of the form
1660 10For every promoted arithmetic type T, there exist candidate operator
1661 functions of the form
1665 case CONVERT_EXPR: /* unary + */
1666 if (TREE_CODE (type1) == POINTER_TYPE)
1669 if (ARITHMETIC_TYPE_P (type1))
1673 /* 11For every promoted integral type T, there exist candidate operator
1674 functions of the form
1678 if (INTEGRAL_TYPE_P (type1))
1682 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1683 is the same type as C2 or is a derived class of C2, T is a complete
1684 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1685 there exist candidate operator functions of the form
1686 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1687 where CV12 is the union of CV1 and CV2. */
1690 if (TREE_CODE (type1) == POINTER_TYPE
1691 && TYPE_PTR_TO_MEMBER_P (type2))
1693 tree c1 = TREE_TYPE (type1);
1694 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1696 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1697 && (TYPE_PTRMEMFUNC_P (type2)
1698 || is_complete (TREE_TYPE (TREE_TYPE (type2)))))
1703 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1704 didate operator functions of the form
1709 bool operator<(L, R);
1710 bool operator>(L, R);
1711 bool operator<=(L, R);
1712 bool operator>=(L, R);
1713 bool operator==(L, R);
1714 bool operator!=(L, R);
1715 where LR is the result of the usual arithmetic conversions between
1718 14For every pair of types T and I, where T is a cv-qualified or cv-
1719 unqualified complete object type and I is a promoted integral type,
1720 there exist candidate operator functions of the form
1721 T* operator+(T*, I);
1722 T& operator[](T*, I);
1723 T* operator-(T*, I);
1724 T* operator+(I, T*);
1725 T& operator[](I, T*);
1727 15For every T, where T is a pointer to complete object type, there exist
1728 candidate operator functions of the form112)
1729 ptrdiff_t operator-(T, T);
1731 16For every pointer or enumeration type T, there exist candidate operator
1732 functions of the form
1733 bool operator<(T, T);
1734 bool operator>(T, T);
1735 bool operator<=(T, T);
1736 bool operator>=(T, T);
1737 bool operator==(T, T);
1738 bool operator!=(T, T);
1740 17For every pointer to member type T, there exist candidate operator
1741 functions of the form
1742 bool operator==(T, T);
1743 bool operator!=(T, T); */
1746 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1748 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1750 type2 = ptrdiff_type_node;
1754 case TRUNC_DIV_EXPR:
1755 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1761 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1762 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1764 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1769 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1781 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1783 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1785 if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
1787 if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
1792 if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
1800 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1803 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1805 type1 = ptrdiff_type_node;
1808 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1810 type2 = ptrdiff_type_node;
1815 /* 18For every pair of promoted integral types L and R, there exist candi-
1816 date operator functions of the form
1823 where LR is the result of the usual arithmetic conversions between
1826 case TRUNC_MOD_EXPR:
1832 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1836 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1837 type, VQ is either volatile or empty, and R is a promoted arithmetic
1838 type, there exist candidate operator functions of the form
1839 VQ L& operator=(VQ L&, R);
1840 VQ L& operator*=(VQ L&, R);
1841 VQ L& operator/=(VQ L&, R);
1842 VQ L& operator+=(VQ L&, R);
1843 VQ L& operator-=(VQ L&, R);
1845 20For every pair T, VQ), where T is any type and VQ is either volatile
1846 or empty, there exist candidate operator functions of the form
1847 T*VQ& operator=(T*VQ&, T*);
1849 21For every pair T, VQ), where T is a pointer to member type and VQ is
1850 either volatile or empty, there exist candidate operator functions of
1852 VQ T& operator=(VQ T&, T);
1854 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1855 unqualified complete object type, VQ is either volatile or empty, and
1856 I is a promoted integral type, there exist candidate operator func-
1858 T*VQ& operator+=(T*VQ&, I);
1859 T*VQ& operator-=(T*VQ&, I);
1861 23For every triple L, VQ, R), where L is an integral or enumeration
1862 type, VQ is either volatile or empty, and R is a promoted integral
1863 type, there exist candidate operator functions of the form
1865 VQ L& operator%=(VQ L&, R);
1866 VQ L& operator<<=(VQ L&, R);
1867 VQ L& operator>>=(VQ L&, R);
1868 VQ L& operator&=(VQ L&, R);
1869 VQ L& operator^=(VQ L&, R);
1870 VQ L& operator|=(VQ L&, R); */
1877 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1879 type2 = ptrdiff_type_node;
1883 case TRUNC_DIV_EXPR:
1884 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1888 case TRUNC_MOD_EXPR:
1894 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1899 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1901 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1902 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1903 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1904 || ((TYPE_PTRMEMFUNC_P (type1)
1905 || TREE_CODE (type1) == POINTER_TYPE)
1906 && null_ptr_cst_p (args[1])))
1916 type1 = build_reference_type (type1);
1922 For every pair of promoted arithmetic types L and R, there
1923 exist candidate operator functions of the form
1925 LR operator?(bool, L, R);
1927 where LR is the result of the usual arithmetic conversions
1928 between types L and R.
1930 For every type T, where T is a pointer or pointer-to-member
1931 type, there exist candidate operator functions of the form T
1932 operator?(bool, T, T); */
1934 if (promoted_arithmetic_type_p (type1)
1935 && promoted_arithmetic_type_p (type2))
1939 /* Otherwise, the types should be pointers. */
1940 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
1941 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
1944 /* We don't check that the two types are the same; the logic
1945 below will actually create two candidates; one in which both
1946 parameter types are TYPE1, and one in which both parameter
1954 /* If we're dealing with two pointer types or two enumeral types,
1955 we need candidates for both of them. */
1956 if (type2 && !same_type_p (type1, type2)
1957 && TREE_CODE (type1) == TREE_CODE (type2)
1958 && (TREE_CODE (type1) == REFERENCE_TYPE
1959 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1960 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1961 || TYPE_PTRMEMFUNC_P (type1)
1962 || IS_AGGR_TYPE (type1)
1963 || TREE_CODE (type1) == ENUMERAL_TYPE))
1965 build_builtin_candidate
1966 (candidates, fnname, type1, type1, args, argtypes, flags);
1967 build_builtin_candidate
1968 (candidates, fnname, type2, type2, args, argtypes, flags);
1972 build_builtin_candidate
1973 (candidates, fnname, type1, type2, args, argtypes, flags);
1977 type_decays_to (tree type)
1979 if (TREE_CODE (type) == ARRAY_TYPE)
1980 return build_pointer_type (TREE_TYPE (type));
1981 if (TREE_CODE (type) == FUNCTION_TYPE)
1982 return build_pointer_type (type);
1986 /* There are three conditions of builtin candidates:
1988 1) bool-taking candidates. These are the same regardless of the input.
1989 2) pointer-pair taking candidates. These are generated for each type
1990 one of the input types converts to.
1991 3) arithmetic candidates. According to the standard, we should generate
1992 all of these, but I'm trying not to...
1994 Here we generate a superset of the possible candidates for this particular
1995 case. That is a subset of the full set the standard defines, plus some
1996 other cases which the standard disallows. add_builtin_candidate will
1997 filter out the invalid set. */
2000 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
2001 enum tree_code code2, tree fnname, tree *args,
2006 tree type, argtypes[3];
2007 /* TYPES[i] is the set of possible builtin-operator parameter types
2008 we will consider for the Ith argument. These are represented as
2009 a TREE_LIST; the TREE_VALUE of each node is the potential
2013 for (i = 0; i < 3; ++i)
2016 argtypes[i] = lvalue_type (args[i]);
2018 argtypes[i] = NULL_TREE;
2023 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2024 and VQ is either volatile or empty, there exist candidate operator
2025 functions of the form
2026 VQ T& operator++(VQ T&); */
2028 case POSTINCREMENT_EXPR:
2029 case PREINCREMENT_EXPR:
2030 case POSTDECREMENT_EXPR:
2031 case PREDECREMENT_EXPR:
2036 /* 24There also exist candidate operator functions of the form
2037 bool operator!(bool);
2038 bool operator&&(bool, bool);
2039 bool operator||(bool, bool); */
2041 case TRUTH_NOT_EXPR:
2042 build_builtin_candidate
2043 (candidates, fnname, boolean_type_node,
2044 NULL_TREE, args, argtypes, flags);
2047 case TRUTH_ORIF_EXPR:
2048 case TRUTH_ANDIF_EXPR:
2049 build_builtin_candidate
2050 (candidates, fnname, boolean_type_node,
2051 boolean_type_node, args, argtypes, flags);
2073 types[0] = types[1] = NULL_TREE;
2075 for (i = 0; i < 2; ++i)
2079 else if (IS_AGGR_TYPE (argtypes[i]))
2083 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2086 convs = lookup_conversions (argtypes[i]);
2088 if (code == COND_EXPR)
2090 if (real_lvalue_p (args[i]))
2091 types[i] = tree_cons
2092 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2094 types[i] = tree_cons
2095 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2101 for (; convs; convs = TREE_CHAIN (convs))
2103 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2106 && (TREE_CODE (type) != REFERENCE_TYPE
2107 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2110 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2111 types[i] = tree_cons (NULL_TREE, type, types[i]);
2113 type = non_reference (type);
2114 if (i != 0 || ! ref1)
2116 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2117 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2118 types[i] = tree_cons (NULL_TREE, type, types[i]);
2119 if (INTEGRAL_TYPE_P (type))
2120 type = type_promotes_to (type);
2123 if (! value_member (type, types[i]))
2124 types[i] = tree_cons (NULL_TREE, type, types[i]);
2129 if (code == COND_EXPR && real_lvalue_p (args[i]))
2130 types[i] = tree_cons
2131 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2132 type = non_reference (argtypes[i]);
2133 if (i != 0 || ! ref1)
2135 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2136 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2137 types[i] = tree_cons (NULL_TREE, type, types[i]);
2138 if (INTEGRAL_TYPE_P (type))
2139 type = type_promotes_to (type);
2141 types[i] = tree_cons (NULL_TREE, type, types[i]);
2145 /* Run through the possible parameter types of both arguments,
2146 creating candidates with those parameter types. */
2147 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2150 for (type = types[1]; type; type = TREE_CHAIN (type))
2151 add_builtin_candidate
2152 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2153 TREE_VALUE (type), args, argtypes, flags);
2155 add_builtin_candidate
2156 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2157 NULL_TREE, args, argtypes, flags);
2164 /* If TMPL can be successfully instantiated as indicated by
2165 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2167 TMPL is the template. EXPLICIT_TARGS are any explicit template
2168 arguments. ARGLIST is the arguments provided at the call-site.
2169 The RETURN_TYPE is the desired type for conversion operators. If
2170 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2171 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2172 add_conv_candidate. */
2174 static struct z_candidate*
2175 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2176 tree ctype, tree explicit_targs, tree arglist,
2177 tree return_type, tree access_path,
2178 tree conversion_path, int flags, tree obj,
2179 unification_kind_t strict)
2181 int ntparms = DECL_NTPARMS (tmpl);
2182 tree targs = make_tree_vec (ntparms);
2183 tree args_without_in_chrg = arglist;
2184 struct z_candidate *cand;
2188 /* We don't do deduction on the in-charge parameter, the VTT
2189 parameter or 'this'. */
2190 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2191 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2193 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2194 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2195 && TYPE_USES_VIRTUAL_BASECLASSES (DECL_CONTEXT (tmpl)))
2196 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2198 i = fn_type_unification (tmpl, explicit_targs, targs,
2199 args_without_in_chrg,
2200 return_type, strict, -1);
2205 fn = instantiate_template (tmpl, targs, tf_none);
2206 if (fn == error_mark_node)
2211 A member function template is never instantiated to perform the
2212 copy of a class object to an object of its class type.
2214 It's a little unclear what this means; the standard explicitly
2215 does allow a template to be used to copy a class. For example,
2220 template <class T> A(const T&);
2223 void g () { A a (f ()); }
2225 the member template will be used to make the copy. The section
2226 quoted above appears in the paragraph that forbids constructors
2227 whose only parameter is (a possibly cv-qualified variant of) the
2228 class type, and a logical interpretation is that the intent was
2229 to forbid the instantiation of member templates which would then
2231 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2233 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2234 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2239 if (obj != NULL_TREE)
2240 /* Aha, this is a conversion function. */
2241 cand = add_conv_candidate (candidates, fn, obj, access_path,
2242 conversion_path, arglist);
2244 cand = add_function_candidate (candidates, fn, ctype,
2245 arglist, access_path,
2246 conversion_path, flags);
2247 if (DECL_TI_TEMPLATE (fn) != tmpl)
2248 /* This situation can occur if a member template of a template
2249 class is specialized. Then, instantiate_template might return
2250 an instantiation of the specialization, in which case the
2251 DECL_TI_TEMPLATE field will point at the original
2252 specialization. For example:
2254 template <class T> struct S { template <class U> void f(U);
2255 template <> void f(int) {}; };
2259 Here, TMPL will be template <class U> S<double>::f(U).
2260 And, instantiate template will give us the specialization
2261 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2262 for this will point at template <class T> template <> S<T>::f(int),
2263 so that we can find the definition. For the purposes of
2264 overload resolution, however, we want the original TMPL. */
2265 cand->template = tree_cons (tmpl, targs, NULL_TREE);
2267 cand->template = DECL_TEMPLATE_INFO (fn);
2273 static struct z_candidate *
2274 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2275 tree explicit_targs, tree arglist, tree return_type,
2276 tree access_path, tree conversion_path, int flags,
2277 unification_kind_t strict)
2280 add_template_candidate_real (candidates, tmpl, ctype,
2281 explicit_targs, arglist, return_type,
2282 access_path, conversion_path,
2283 flags, NULL_TREE, strict);
2287 static struct z_candidate *
2288 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2289 tree obj, tree arglist, tree return_type,
2290 tree access_path, tree conversion_path)
2293 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2294 arglist, return_type, access_path,
2295 conversion_path, 0, obj, DEDUCE_CONV);
2298 /* The CANDS are the set of candidates that were considered for
2299 overload resolution. Return the set of viable candidates. If none
2300 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2301 is true if a candidate should be considered viable only if it is
2304 static struct z_candidate*
2305 splice_viable (struct z_candidate *cands,
2309 struct z_candidate *viable;
2310 struct z_candidate **last_viable;
2311 struct z_candidate **cand;
2314 last_viable = &viable;
2315 *any_viable_p = false;
2320 struct z_candidate *c = *cand;
2321 if (strict_p ? c->viable == 1 : c->viable)
2326 last_viable = &c->next;
2327 *any_viable_p = true;
2333 return viable ? viable : cands;
2337 any_strictly_viable (struct z_candidate *cands)
2339 for (; cands; cands = cands->next)
2340 if (cands->viable == 1)
2346 build_this (tree obj)
2348 /* Fix this to work on non-lvalues. */
2349 return build_unary_op (ADDR_EXPR, obj, 0);
2352 /* Returns true iff functions are equivalent. Equivalent functions are
2353 not '==' only if one is a function-local extern function or if
2354 both are extern "C". */
2357 equal_functions (tree fn1, tree fn2)
2359 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2360 || DECL_EXTERN_C_FUNCTION_P (fn1))
2361 return decls_match (fn1, fn2);
2365 /* Print information about one overload candidate CANDIDATE. MSGSTR
2366 is the text to print before the candidate itself.
2368 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2369 to have been run through gettext by the caller. This wart makes
2370 life simpler in print_z_candidates and for the translators. */
2373 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2375 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2377 if (candidate->num_convs == 3)
2378 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2379 candidate->convs[0]->type,
2380 candidate->convs[1]->type,
2381 candidate->convs[2]->type);
2382 else if (candidate->num_convs == 2)
2383 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2384 candidate->convs[0]->type,
2385 candidate->convs[1]->type);
2387 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2388 candidate->convs[0]->type);
2390 else if (TYPE_P (candidate->fn))
2391 inform ("%s %T <conversion>", msgstr, candidate->fn);
2392 else if (candidate->viable == -1)
2393 inform ("%J%s %+#D <near match>", candidate->fn, msgstr, candidate->fn);
2395 inform ("%J%s %+#D", candidate->fn, msgstr, candidate->fn);
2399 print_z_candidates (struct z_candidate *candidates)
2402 struct z_candidate *cand1;
2403 struct z_candidate **cand2;
2405 /* There may be duplicates in the set of candidates. We put off
2406 checking this condition as long as possible, since we have no way
2407 to eliminate duplicates from a set of functions in less than n^2
2408 time. Now we are about to emit an error message, so it is more
2409 permissible to go slowly. */
2410 for (cand1 = candidates; cand1; cand1 = cand1->next)
2412 tree fn = cand1->fn;
2413 /* Skip builtin candidates and conversion functions. */
2414 if (TREE_CODE (fn) != FUNCTION_DECL)
2416 cand2 = &cand1->next;
2419 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2420 && equal_functions (fn, (*cand2)->fn))
2421 *cand2 = (*cand2)->next;
2423 cand2 = &(*cand2)->next;
2430 str = _("candidates are:");
2431 print_z_candidate (str, candidates);
2432 if (candidates->next)
2434 /* Indent successive candidates by the width of the translation
2435 of the above string. */
2436 size_t len = gcc_gettext_width (str) + 1;
2437 char *spaces = alloca (len);
2438 memset (spaces, ' ', len-1);
2439 spaces[len - 1] = '\0';
2441 candidates = candidates->next;
2444 print_z_candidate (spaces, candidates);
2445 candidates = candidates->next;
2451 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2452 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2453 the result of the conversion function to convert it to the final
2454 desired type. Merge the the two sequences into a single sequence,
2455 and return the merged sequence. */
2458 merge_conversion_sequences (conversion *user_seq, conversion *std_seq)
2462 my_friendly_assert (user_seq->kind == ck_user, 20030306);
2464 /* Find the end of the second conversion sequence. */
2466 while ((*t)->kind != ck_identity)
2467 t = &((*t)->u.next);
2469 /* Replace the identity conversion with the user conversion
2473 /* The entire sequence is a user-conversion sequence. */
2474 std_seq->user_conv_p = true;
2479 /* Returns the best overload candidate to perform the requested
2480 conversion. This function is used for three the overloading situations
2481 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2482 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2483 per [dcl.init.ref], so we ignore temporary bindings. */
2485 static struct z_candidate *
2486 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2488 struct z_candidate *candidates, *cand;
2489 tree fromtype = TREE_TYPE (expr);
2490 tree ctors = NULL_TREE;
2491 tree conv_fns = NULL_TREE;
2492 conversion *conv = NULL;
2493 tree args = NULL_TREE;
2496 /* We represent conversion within a hierarchy using RVALUE_CONV and
2497 BASE_CONV, as specified by [over.best.ics]; these become plain
2498 constructor calls, as specified in [dcl.init]. */
2499 my_friendly_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2500 || !DERIVED_FROM_P (totype, fromtype), 20011226);
2502 if (IS_AGGR_TYPE (totype))
2503 ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
2505 if (IS_AGGR_TYPE (fromtype))
2506 conv_fns = lookup_conversions (fromtype);
2509 flags |= LOOKUP_NO_CONVERSION;
2515 ctors = BASELINK_FUNCTIONS (ctors);
2517 t = build_int_2 (0, 0);
2518 TREE_TYPE (t) = build_pointer_type (totype);
2519 args = build_tree_list (NULL_TREE, expr);
2520 /* We should never try to call the abstract or base constructor
2522 my_friendly_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2523 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)),
2525 args = tree_cons (NULL_TREE, t, args);
2527 for (; ctors; ctors = OVL_NEXT (ctors))
2529 tree ctor = OVL_CURRENT (ctors);
2530 if (DECL_NONCONVERTING_P (ctor))
2533 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2534 cand = add_template_candidate (&candidates, ctor, totype,
2535 NULL_TREE, args, NULL_TREE,
2536 TYPE_BINFO (totype),
2537 TYPE_BINFO (totype),
2541 cand = add_function_candidate (&candidates, ctor, totype,
2542 args, TYPE_BINFO (totype),
2543 TYPE_BINFO (totype),
2547 cand->second_conv = build_identity_conv (totype, NULL_TREE);
2551 args = build_tree_list (NULL_TREE, build_this (expr));
2553 for (; conv_fns; conv_fns = TREE_CHAIN (conv_fns))
2556 tree conversion_path = TREE_PURPOSE (conv_fns);
2557 int convflags = LOOKUP_NO_CONVERSION;
2559 /* If we are called to convert to a reference type, we are trying to
2560 find an lvalue binding, so don't even consider temporaries. If
2561 we don't find an lvalue binding, the caller will try again to
2562 look for a temporary binding. */
2563 if (TREE_CODE (totype) == REFERENCE_TYPE)
2564 convflags |= LOOKUP_NO_TEMP_BIND;
2566 for (fns = TREE_VALUE (conv_fns); fns; fns = OVL_NEXT (fns))
2568 tree fn = OVL_CURRENT (fns);
2570 /* [over.match.funcs] For conversion functions, the function
2571 is considered to be a member of the class of the implicit
2572 object argument for the purpose of defining the type of
2573 the implicit object parameter.
2575 So we pass fromtype as CTYPE to add_*_candidate. */
2577 if (TREE_CODE (fn) == TEMPLATE_DECL)
2578 cand = add_template_candidate (&candidates, fn, fromtype,
2581 TYPE_BINFO (fromtype),
2586 cand = add_function_candidate (&candidates, fn, fromtype,
2588 TYPE_BINFO (fromtype),
2595 = implicit_conversion (totype,
2596 TREE_TYPE (TREE_TYPE (cand->fn)),
2599 cand->second_conv = ics;
2603 else if (candidates->viable == 1 && ics->bad_p)
2609 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2613 cand = tourney (candidates);
2616 if (flags & LOOKUP_COMPLAIN)
2618 error ("conversion from `%T' to `%T' is ambiguous",
2620 print_z_candidates (candidates);
2623 cand = candidates; /* any one will do */
2624 cand->second_conv = build_ambiguous_conv (totype, expr);
2625 cand->second_conv->user_conv_p = true;
2626 if (!any_strictly_viable (candidates))
2627 cand->second_conv->bad_p = true;
2628 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2629 ambiguous conversion is no worse than another user-defined
2635 /* Build the user conversion sequence. */
2638 (DECL_CONSTRUCTOR_P (cand->fn)
2639 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2640 build_identity_conv (TREE_TYPE (expr), expr));
2643 /* Combine it with the second conversion sequence. */
2644 cand->second_conv = merge_conversion_sequences (conv,
2647 if (cand->viable == -1)
2648 cand->second_conv->bad_p = true;
2654 build_user_type_conversion (tree totype, tree expr, int flags)
2656 struct z_candidate *cand
2657 = build_user_type_conversion_1 (totype, expr, flags);
2661 if (cand->second_conv->kind == ck_ambig)
2662 return error_mark_node;
2663 return convert_from_reference (convert_like (cand->second_conv, expr));
2668 /* Do any initial processing on the arguments to a function call. */
2671 resolve_args (tree args)
2674 for (t = args; t; t = TREE_CHAIN (t))
2676 tree arg = TREE_VALUE (t);
2678 if (arg == error_mark_node)
2679 return error_mark_node;
2680 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2682 error ("invalid use of void expression");
2683 return error_mark_node;
2685 arg = convert_from_reference (arg);
2686 TREE_VALUE (t) = arg;
2691 /* Perform overload resolution on FN, which is called with the ARGS.
2693 Return the candidate function selected by overload resolution, or
2694 NULL if the event that overload resolution failed. In the case
2695 that overload resolution fails, *CANDIDATES will be the set of
2696 candidates considered, and ANY_VIABLE_P will be set to true or
2697 false to indicate whether or not any of the candidates were
2700 The ARGS should already have gone through RESOLVE_ARGS before this
2701 function is called. */
2703 static struct z_candidate *
2704 perform_overload_resolution (tree fn,
2706 struct z_candidate **candidates,
2709 struct z_candidate *cand;
2710 tree explicit_targs = NULL_TREE;
2711 int template_only = 0;
2714 *any_viable_p = true;
2716 /* Check FN and ARGS. */
2717 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
2718 || TREE_CODE (fn) == TEMPLATE_DECL
2719 || TREE_CODE (fn) == OVERLOAD
2720 || TREE_CODE (fn) == TEMPLATE_ID_EXPR,
2722 my_friendly_assert (!args || TREE_CODE (args) == TREE_LIST,
2725 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2727 explicit_targs = TREE_OPERAND (fn, 1);
2728 fn = TREE_OPERAND (fn, 0);
2732 /* Add the various candidate functions. */
2733 add_candidates (fn, args, explicit_targs, template_only,
2734 /*conversion_path=*/NULL_TREE,
2735 /*access_path=*/NULL_TREE,
2739 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2743 cand = tourney (*candidates);
2747 /* Return an expression for a call to FN (a namespace-scope function,
2748 or a static member function) with the ARGS. */
2751 build_new_function_call (tree fn, tree args)
2753 struct z_candidate *candidates, *cand;
2758 args = resolve_args (args);
2759 if (args == error_mark_node)
2760 return error_mark_node;
2762 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2763 p = conversion_obstack_alloc (0);
2765 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2769 if (!any_viable_p && candidates && ! candidates->next)
2770 return build_function_call (candidates->fn, args);
2771 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2772 fn = TREE_OPERAND (fn, 0);
2774 error ("no matching function for call to `%D(%A)'",
2775 DECL_NAME (OVL_CURRENT (fn)), args);
2777 error ("call of overloaded `%D(%A)' is ambiguous",
2778 DECL_NAME (OVL_CURRENT (fn)), args);
2780 print_z_candidates (candidates);
2781 result = error_mark_node;
2784 result = build_over_call (cand, LOOKUP_NORMAL);
2786 /* Free all the conversions we allocated. */
2787 obstack_free (&conversion_obstack, p);
2792 /* Build a call to a global operator new. FNNAME is the name of the
2793 operator (either "operator new" or "operator new[]") and ARGS are
2794 the arguments provided. *SIZE points to the total number of bytes
2795 required by the allocation, and is updated if that is changed here.
2796 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2797 function determines that no cookie should be used, after all,
2798 *COOKIE_SIZE is set to NULL_TREE. */
2801 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2804 struct z_candidate *candidates;
2805 struct z_candidate *cand;
2808 args = tree_cons (NULL_TREE, *size, args);
2809 args = resolve_args (args);
2810 if (args == error_mark_node)
2817 If this lookup fails to find the name, or if the allocated type
2818 is not a class type, the allocation function's name is looked
2819 up in the global scope.
2821 we disregard block-scope declarations of "operator new". */
2822 fns = lookup_function_nonclass (fnname, args, /*block_p=*/false);
2824 /* Figure out what function is being called. */
2825 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2827 /* If no suitable function could be found, issue an error message
2832 error ("no matching function for call to `%D(%A)'",
2833 DECL_NAME (OVL_CURRENT (fns)), args);
2835 error ("call of overloaded `%D(%A)' is ambiguous",
2836 DECL_NAME (OVL_CURRENT (fns)), args);
2838 print_z_candidates (candidates);
2839 return error_mark_node;
2842 /* If a cookie is required, add some extra space. Whether
2843 or not a cookie is required cannot be determined until
2844 after we know which function was called. */
2847 bool use_cookie = true;
2848 if (!abi_version_at_least (2))
2850 tree placement = TREE_CHAIN (args);
2851 /* In G++ 3.2, the check was implemented incorrectly; it
2852 looked at the placement expression, rather than the
2853 type of the function. */
2854 if (placement && !TREE_CHAIN (placement)
2855 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2863 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2864 /* Skip the size_t parameter. */
2865 arg_types = TREE_CHAIN (arg_types);
2866 /* Check the remaining parameters (if any). */
2868 && TREE_CHAIN (arg_types) == void_list_node
2869 && same_type_p (TREE_VALUE (arg_types),
2873 /* If we need a cookie, adjust the number of bytes allocated. */
2876 /* Update the total size. */
2877 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2878 /* Update the argument list to reflect the adjusted size. */
2879 TREE_VALUE (args) = *size;
2882 *cookie_size = NULL_TREE;
2885 /* Build the CALL_EXPR. */
2886 return build_over_call (cand, LOOKUP_NORMAL);
2890 build_object_call (tree obj, tree args)
2892 struct z_candidate *candidates = 0, *cand;
2893 tree fns, convs, mem_args = NULL_TREE;
2894 tree type = TREE_TYPE (obj);
2896 tree result = NULL_TREE;
2899 if (TYPE_PTRMEMFUNC_P (type))
2901 /* It's no good looking for an overloaded operator() on a
2902 pointer-to-member-function. */
2903 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2904 return error_mark_node;
2907 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2908 if (fns == error_mark_node)
2909 return error_mark_node;
2911 args = resolve_args (args);
2913 if (args == error_mark_node)
2914 return error_mark_node;
2916 /* Get the high-water mark for the CONVERSION_OBSTACK. */
2917 p = conversion_obstack_alloc (0);
2921 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2922 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2924 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2926 tree fn = OVL_CURRENT (fns);
2927 if (TREE_CODE (fn) == TEMPLATE_DECL)
2928 add_template_candidate (&candidates, fn, base, NULL_TREE,
2929 mem_args, NULL_TREE,
2932 LOOKUP_NORMAL, DEDUCE_CALL);
2934 add_function_candidate
2935 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2936 TYPE_BINFO (type), LOOKUP_NORMAL);
2940 convs = lookup_conversions (type);
2942 for (; convs; convs = TREE_CHAIN (convs))
2944 tree fns = TREE_VALUE (convs);
2945 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2947 if ((TREE_CODE (totype) == POINTER_TYPE
2948 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2949 || (TREE_CODE (totype) == REFERENCE_TYPE
2950 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2951 || (TREE_CODE (totype) == REFERENCE_TYPE
2952 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2953 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2954 for (; fns; fns = OVL_NEXT (fns))
2956 tree fn = OVL_CURRENT (fns);
2957 if (TREE_CODE (fn) == TEMPLATE_DECL)
2958 add_template_conv_candidate
2959 (&candidates, fn, obj, args, totype,
2960 /*access_path=*/NULL_TREE,
2961 /*conversion_path=*/NULL_TREE);
2963 add_conv_candidate (&candidates, fn, obj, args,
2964 /*conversion_path=*/NULL_TREE,
2965 /*access_path=*/NULL_TREE);
2969 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2972 error ("no match for call to `(%T) (%A)'", TREE_TYPE (obj), args);
2973 print_z_candidates (candidates);
2974 result = error_mark_node;
2978 cand = tourney (candidates);
2981 error ("call of `(%T) (%A)' is ambiguous", TREE_TYPE (obj), args);
2982 print_z_candidates (candidates);
2983 result = error_mark_node;
2985 /* Since cand->fn will be a type, not a function, for a conversion
2986 function, we must be careful not to unconditionally look at
2988 else if (TREE_CODE (cand->fn) == FUNCTION_DECL
2989 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
2990 result = build_over_call (cand, LOOKUP_NORMAL);
2993 obj = convert_like_with_context (cand->convs[0], obj, cand->fn, -1);
2994 result = build_function_call (obj, args);
2998 /* Free all the conversions we allocated. */
2999 obstack_free (&conversion_obstack, p);
3005 op_error (enum tree_code code, enum tree_code code2,
3006 tree arg1, tree arg2, tree arg3, const char *problem)
3010 if (code == MODIFY_EXPR)
3011 opname = assignment_operator_name_info[code2].name;
3013 opname = operator_name_info[code].name;
3018 error ("%s for ternary 'operator?:' in '%E ? %E : %E'",
3019 problem, arg1, arg2, arg3);
3022 case POSTINCREMENT_EXPR:
3023 case POSTDECREMENT_EXPR:
3024 error ("%s for 'operator%s' in '%E%s'", problem, opname, arg1, opname);
3028 error ("%s for 'operator[]' in '%E[%E]'", problem, arg1, arg2);
3033 error ("%s for '%s' in '%s %E'", problem, opname, opname, arg1);
3038 error ("%s for 'operator%s' in '%E %s %E'",
3039 problem, opname, arg1, opname, arg2);
3041 error ("%s for 'operator%s' in '%s%E'",
3042 problem, opname, opname, arg1);
3047 /* Return the implicit conversion sequence that could be used to
3048 convert E1 to E2 in [expr.cond]. */
3051 conditional_conversion (tree e1, tree e2)
3053 tree t1 = non_reference (TREE_TYPE (e1));
3054 tree t2 = non_reference (TREE_TYPE (e2));
3060 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3061 implicitly converted (clause _conv_) to the type "reference to
3062 T2", subject to the constraint that in the conversion the
3063 reference must bind directly (_dcl.init.ref_) to E1. */
3064 if (real_lvalue_p (e2))
3066 conv = implicit_conversion (build_reference_type (t2),
3069 LOOKUP_NO_TEMP_BIND);
3076 If E1 and E2 have class type, and the underlying class types are
3077 the same or one is a base class of the other: E1 can be converted
3078 to match E2 if the class of T2 is the same type as, or a base
3079 class of, the class of T1, and the cv-qualification of T2 is the
3080 same cv-qualification as, or a greater cv-qualification than, the
3081 cv-qualification of T1. If the conversion is applied, E1 is
3082 changed to an rvalue of type T2 that still refers to the original
3083 source class object (or the appropriate subobject thereof). */
3084 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3085 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3087 if (good_base && at_least_as_qualified_p (t2, t1))
3089 conv = build_identity_conv (t1, e1);
3090 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3091 TYPE_MAIN_VARIANT (t2)))
3092 conv = build_conv (ck_base, t2, conv);
3094 conv = build_conv (ck_rvalue, t2, conv);
3103 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3104 converted to the type that expression E2 would have if E2 were
3105 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3106 return implicit_conversion (t2, t1, e1, LOOKUP_NORMAL);
3109 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3110 arguments to the conditional expression. */
3113 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3117 tree result = NULL_TREE;
3118 tree result_type = NULL_TREE;
3119 bool lvalue_p = true;
3120 struct z_candidate *candidates = 0;
3121 struct z_candidate *cand;
3124 /* As a G++ extension, the second argument to the conditional can be
3125 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3126 c'.) If the second operand is omitted, make sure it is
3127 calculated only once. */
3131 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3133 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3134 if (real_lvalue_p (arg1))
3135 arg2 = arg1 = stabilize_reference (arg1);
3137 arg2 = arg1 = save_expr (arg1);
3142 The first expr ession is implicitly converted to bool (clause
3144 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3146 /* If something has already gone wrong, just pass that fact up the
3148 if (error_operand_p (arg1)
3149 || error_operand_p (arg2)
3150 || error_operand_p (arg3))
3151 return error_mark_node;
3155 If either the second or the third operand has type (possibly
3156 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3157 array-to-pointer (_conv.array_), and function-to-pointer
3158 (_conv.func_) standard conversions are performed on the second
3159 and third operands. */
3160 arg2_type = TREE_TYPE (arg2);
3161 arg3_type = TREE_TYPE (arg3);
3162 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3164 /* Do the conversions. We don't these for `void' type arguments
3165 since it can't have any effect and since decay_conversion
3166 does not handle that case gracefully. */
3167 if (!VOID_TYPE_P (arg2_type))
3168 arg2 = decay_conversion (arg2);
3169 if (!VOID_TYPE_P (arg3_type))
3170 arg3 = decay_conversion (arg3);
3171 arg2_type = TREE_TYPE (arg2);
3172 arg3_type = TREE_TYPE (arg3);
3176 One of the following shall hold:
3178 --The second or the third operand (but not both) is a
3179 throw-expression (_except.throw_); the result is of the
3180 type of the other and is an rvalue.
3182 --Both the second and the third operands have type void; the
3183 result is of type void and is an rvalue.
3185 We must avoid calling force_rvalue for expressions of type
3186 "void" because it will complain that their value is being
3188 if (TREE_CODE (arg2) == THROW_EXPR
3189 && TREE_CODE (arg3) != THROW_EXPR)
3191 if (!VOID_TYPE_P (arg3_type))
3192 arg3 = force_rvalue (arg3);
3193 arg3_type = TREE_TYPE (arg3);
3194 result_type = arg3_type;
3196 else if (TREE_CODE (arg2) != THROW_EXPR
3197 && TREE_CODE (arg3) == THROW_EXPR)
3199 if (!VOID_TYPE_P (arg2_type))
3200 arg2 = force_rvalue (arg2);
3201 arg2_type = TREE_TYPE (arg2);
3202 result_type = arg2_type;
3204 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3205 result_type = void_type_node;
3208 error ("`%E' has type `void' and is not a throw-expression",
3209 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3210 return error_mark_node;
3214 goto valid_operands;
3218 Otherwise, if the second and third operand have different types,
3219 and either has (possibly cv-qualified) class type, an attempt is
3220 made to convert each of those operands to the type of the other. */
3221 else if (!same_type_p (arg2_type, arg3_type)
3222 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3227 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3228 p = conversion_obstack_alloc (0);
3230 conv2 = conditional_conversion (arg2, arg3);
3231 conv3 = conditional_conversion (arg3, arg2);
3235 If both can be converted, or one can be converted but the
3236 conversion is ambiguous, the program is ill-formed. If
3237 neither can be converted, the operands are left unchanged and
3238 further checking is performed as described below. If exactly
3239 one conversion is possible, that conversion is applied to the
3240 chosen operand and the converted operand is used in place of
3241 the original operand for the remainder of this section. */
3242 if ((conv2 && !conv2->bad_p
3243 && conv3 && !conv3->bad_p)
3244 || (conv2 && conv2->kind == ck_ambig)
3245 || (conv3 && conv3->kind == ck_ambig))
3247 error ("operands to ?: have different types");
3248 result = error_mark_node;
3250 else if (conv2 && !conv2->bad_p)
3252 arg2 = convert_like (conv2, arg2);
3253 arg2 = convert_from_reference (arg2);
3254 arg2_type = TREE_TYPE (arg2);
3256 else if (conv3 && !conv3->bad_p)
3258 arg3 = convert_like (conv3, arg3);
3259 arg3 = convert_from_reference (arg3);
3260 arg3_type = TREE_TYPE (arg3);
3263 /* Free all the conversions we allocated. */
3264 obstack_free (&conversion_obstack, p);
3269 /* If, after the conversion, both operands have class type,
3270 treat the cv-qualification of both operands as if it were the
3271 union of the cv-qualification of the operands.
3273 The standard is not clear about what to do in this
3274 circumstance. For example, if the first operand has type
3275 "const X" and the second operand has a user-defined
3276 conversion to "volatile X", what is the type of the second
3277 operand after this step? Making it be "const X" (matching
3278 the first operand) seems wrong, as that discards the
3279 qualification without actually performing a copy. Leaving it
3280 as "volatile X" seems wrong as that will result in the
3281 conditional expression failing altogether, even though,
3282 according to this step, the one operand could be converted to
3283 the type of the other. */
3284 if ((conv2 || conv3)
3285 && CLASS_TYPE_P (arg2_type)
3286 && TYPE_QUALS (arg2_type) != TYPE_QUALS (arg3_type))
3287 arg2_type = arg3_type =
3288 cp_build_qualified_type (arg2_type,
3289 TYPE_QUALS (arg2_type)
3290 | TYPE_QUALS (arg3_type));
3295 If the second and third operands are lvalues and have the same
3296 type, the result is of that type and is an lvalue. */
3297 if (real_lvalue_p (arg2)
3298 && real_lvalue_p (arg3)
3299 && same_type_p (arg2_type, arg3_type))
3301 result_type = arg2_type;
3302 goto valid_operands;
3307 Otherwise, the result is an rvalue. If the second and third
3308 operand do not have the same type, and either has (possibly
3309 cv-qualified) class type, overload resolution is used to
3310 determine the conversions (if any) to be applied to the operands
3311 (_over.match.oper_, _over.built_). */
3313 if (!same_type_p (arg2_type, arg3_type)
3314 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3320 /* Rearrange the arguments so that add_builtin_candidate only has
3321 to know about two args. In build_builtin_candidates, the
3322 arguments are unscrambled. */
3326 add_builtin_candidates (&candidates,
3329 ansi_opname (COND_EXPR),
3335 If the overload resolution fails, the program is
3337 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3340 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3341 print_z_candidates (candidates);
3342 return error_mark_node;
3344 cand = tourney (candidates);
3347 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3348 print_z_candidates (candidates);
3349 return error_mark_node;
3354 Otherwise, the conversions thus determined are applied, and
3355 the converted operands are used in place of the original
3356 operands for the remainder of this section. */
3357 conv = cand->convs[0];
3358 arg1 = convert_like (conv, arg1);
3359 conv = cand->convs[1];
3360 arg2 = convert_like (conv, arg2);
3361 conv = cand->convs[2];
3362 arg3 = convert_like (conv, arg3);
3367 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3368 and function-to-pointer (_conv.func_) standard conversions are
3369 performed on the second and third operands.
3371 We need to force the lvalue-to-rvalue conversion here for class types,
3372 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3373 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3376 arg2 = force_rvalue (arg2);
3377 if (!CLASS_TYPE_P (arg2_type))
3378 arg2_type = TREE_TYPE (arg2);
3380 arg3 = force_rvalue (arg3);
3381 if (!CLASS_TYPE_P (arg2_type))
3382 arg3_type = TREE_TYPE (arg3);
3384 if (arg2 == error_mark_node || arg3 == error_mark_node)
3385 return error_mark_node;
3389 After those conversions, one of the following shall hold:
3391 --The second and third operands have the same type; the result is of
3393 if (same_type_p (arg2_type, arg3_type))
3394 result_type = arg2_type;
3397 --The second and third operands have arithmetic or enumeration
3398 type; the usual arithmetic conversions are performed to bring
3399 them to a common type, and the result is of that type. */
3400 else if ((ARITHMETIC_TYPE_P (arg2_type)
3401 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3402 && (ARITHMETIC_TYPE_P (arg3_type)
3403 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3405 /* In this case, there is always a common type. */
3406 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3409 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3410 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3411 warning ("enumeral mismatch in conditional expression: `%T' vs `%T'",
3412 arg2_type, arg3_type);
3413 else if (extra_warnings
3414 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3415 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3416 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3417 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3418 warning ("enumeral and non-enumeral type in conditional expression");
3420 arg2 = perform_implicit_conversion (result_type, arg2);
3421 arg3 = perform_implicit_conversion (result_type, arg3);
3425 --The second and third operands have pointer type, or one has
3426 pointer type and the other is a null pointer constant; pointer
3427 conversions (_conv.ptr_) and qualification conversions
3428 (_conv.qual_) are performed to bring them to their composite
3429 pointer type (_expr.rel_). The result is of the composite
3432 --The second and third operands have pointer to member type, or
3433 one has pointer to member type and the other is a null pointer
3434 constant; pointer to member conversions (_conv.mem_) and
3435 qualification conversions (_conv.qual_) are performed to bring
3436 them to a common type, whose cv-qualification shall match the
3437 cv-qualification of either the second or the third operand.
3438 The result is of the common type. */
3439 else if ((null_ptr_cst_p (arg2)
3440 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3441 || (null_ptr_cst_p (arg3)
3442 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3443 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3444 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3445 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3447 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3448 arg3, "conditional expression");
3449 if (result_type == error_mark_node)
3450 return error_mark_node;
3451 arg2 = perform_implicit_conversion (result_type, arg2);
3452 arg3 = perform_implicit_conversion (result_type, arg3);
3457 error ("operands to ?: have different types");
3458 return error_mark_node;
3462 result = fold (build (COND_EXPR, result_type, arg1, arg2, arg3));
3463 /* We can't use result_type below, as fold might have returned a
3466 /* Expand both sides into the same slot, hopefully the target of the
3467 ?: expression. We used to check for TARGET_EXPRs here, but now we
3468 sometimes wrap them in NOP_EXPRs so the test would fail. */
3469 if (!lvalue_p && CLASS_TYPE_P (TREE_TYPE (result)))
3470 result = get_target_expr (result);
3472 /* If this expression is an rvalue, but might be mistaken for an
3473 lvalue, we must add a NON_LVALUE_EXPR. */
3474 if (!lvalue_p && real_lvalue_p (result))
3475 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
3480 /* OPERAND is an operand to an expression. Perform necessary steps
3481 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3485 prep_operand (tree operand)
3489 operand = convert_from_reference (operand);
3490 if (CLASS_TYPE_P (TREE_TYPE (operand))
3491 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3492 /* Make sure the template type is instantiated now. */
3493 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3499 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3500 OVERLOAD) to the CANDIDATES, returning an updated list of
3501 CANDIDATES. The ARGS are the arguments provided to the call,
3502 without any implicit object parameter. The EXPLICIT_TARGS are
3503 explicit template arguments provided. TEMPLATE_ONLY is true if
3504 only template functions should be considered. CONVERSION_PATH,
3505 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3508 add_candidates (tree fns, tree args,
3509 tree explicit_targs, bool template_only,
3510 tree conversion_path, tree access_path,
3512 struct z_candidate **candidates)
3515 tree non_static_args;
3517 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3518 /* Delay creating the implicit this parameter until it is needed. */
3519 non_static_args = NULL_TREE;
3526 fn = OVL_CURRENT (fns);
3527 /* Figure out which set of arguments to use. */
3528 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3530 /* If this function is a non-static member, prepend the implicit
3531 object parameter. */
3532 if (!non_static_args)
3533 non_static_args = tree_cons (NULL_TREE,
3534 build_this (TREE_VALUE (args)),
3536 fn_args = non_static_args;
3539 /* Otherwise, just use the list of arguments provided. */
3542 if (TREE_CODE (fn) == TEMPLATE_DECL)
3543 add_template_candidate (candidates,
3553 else if (!template_only)
3554 add_function_candidate (candidates,
3561 fns = OVL_NEXT (fns);
3566 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3,
3569 struct z_candidate *candidates = 0, *cand;
3570 tree arglist, fnname;
3572 tree result = NULL_TREE;
3573 bool result_valid_p = false;
3574 enum tree_code code2 = NOP_EXPR;
3580 if (error_operand_p (arg1)
3581 || error_operand_p (arg2)
3582 || error_operand_p (arg3))
3583 return error_mark_node;
3585 if (code == MODIFY_EXPR)
3587 code2 = TREE_CODE (arg3);
3589 fnname = ansi_assopname (code2);
3592 fnname = ansi_opname (code);
3594 arg1 = prep_operand (arg1);
3600 case VEC_DELETE_EXPR:
3602 /* Use build_op_new_call and build_op_delete_call instead. */
3606 return build_object_call (arg1, arg2);
3612 arg2 = prep_operand (arg2);
3613 arg3 = prep_operand (arg3);
3615 if (code == COND_EXPR)
3617 if (arg2 == NULL_TREE
3618 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3619 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3620 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3621 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3624 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3625 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3628 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3629 arg2 = integer_zero_node;
3631 arglist = NULL_TREE;
3633 arglist = tree_cons (NULL_TREE, arg3, arglist);
3635 arglist = tree_cons (NULL_TREE, arg2, arglist);
3636 arglist = tree_cons (NULL_TREE, arg1, arglist);
3638 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3639 p = conversion_obstack_alloc (0);
3641 /* Add namespace-scope operators to the list of functions to
3643 add_candidates (lookup_function_nonclass (fnname, arglist, /*block_p=*/true),
3644 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3645 flags, &candidates);
3646 /* Add class-member operators to the candidate set. */
3647 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3651 fns = lookup_fnfields (TREE_TYPE (arg1), fnname, 1);
3652 if (fns == error_mark_node)
3654 result = error_mark_node;
3655 goto user_defined_result_ready;
3658 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3660 BASELINK_BINFO (fns),
3661 TYPE_BINFO (TREE_TYPE (arg1)),
3662 flags, &candidates);
3665 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3666 to know about two args; a builtin candidate will always have a first
3667 parameter of type bool. We'll handle that in
3668 build_builtin_candidate. */
3669 if (code == COND_EXPR)
3679 args[2] = NULL_TREE;
3682 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3688 /* For these, the built-in candidates set is empty
3689 [over.match.oper]/3. We don't want non-strict matches
3690 because exact matches are always possible with built-in
3691 operators. The built-in candidate set for COMPONENT_REF
3692 would be empty too, but since there are no such built-in
3693 operators, we accept non-strict matches for them. */
3698 strict_p = pedantic;
3702 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3707 case POSTINCREMENT_EXPR:
3708 case POSTDECREMENT_EXPR:
3709 /* Look for an `operator++ (int)'. If they didn't have
3710 one, then we fall back to the old way of doing things. */
3711 if (flags & LOOKUP_COMPLAIN)
3712 pedwarn ("no `%D(int)' declared for postfix `%s', trying prefix operator instead",
3714 operator_name_info[code].name);
3715 if (code == POSTINCREMENT_EXPR)
3716 code = PREINCREMENT_EXPR;
3718 code = PREDECREMENT_EXPR;
3719 result = build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE,
3723 /* The caller will deal with these. */
3728 result_valid_p = true;
3732 if (flags & LOOKUP_COMPLAIN)
3734 op_error (code, code2, arg1, arg2, arg3, "no match");
3735 print_z_candidates (candidates);
3737 result = error_mark_node;
3743 cand = tourney (candidates);
3746 if (flags & LOOKUP_COMPLAIN)
3748 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3749 print_z_candidates (candidates);
3751 result = error_mark_node;
3753 else if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3756 *overloaded_p = true;
3759 && fnname == ansi_assopname (NOP_EXPR)
3760 && DECL_ARTIFICIAL (cand->fn)
3762 && ! candidates->next->next)
3764 warning ("using synthesized `%#D' for copy assignment",
3766 cp_warning_at (" where cfront would use `%#D'",
3768 ? candidates->next->fn
3772 result = build_over_call (cand, LOOKUP_NORMAL);
3776 /* Give any warnings we noticed during overload resolution. */
3779 struct candidate_warning *w;
3780 for (w = cand->warnings; w; w = w->next)
3781 joust (cand, w->loser, 1);
3784 /* Check for comparison of different enum types. */
3793 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3794 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3795 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3796 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3798 warning ("comparison between `%#T' and `%#T'",
3799 TREE_TYPE (arg1), TREE_TYPE (arg2));
3806 /* We need to strip any leading REF_BIND so that bitfields
3807 don't cause errors. This should not remove any important
3808 conversions, because builtins don't apply to class
3809 objects directly. */
3810 conv = cand->convs[0];
3811 if (conv->kind == ck_ref_bind)
3812 conv = conv->u.next;
3813 arg1 = convert_like (conv, arg1);
3816 conv = cand->convs[1];
3817 if (conv->kind == ck_ref_bind)
3818 conv = conv->u.next;
3819 arg2 = convert_like (conv, arg2);
3823 conv = cand->convs[2];
3824 if (conv->kind == ck_ref_bind)
3825 conv = conv->u.next;
3826 arg3 = convert_like (conv, arg3);
3831 user_defined_result_ready:
3833 /* Free all the conversions we allocated. */
3834 obstack_free (&conversion_obstack, p);
3836 if (result || result_valid_p)
3843 return build_modify_expr (arg1, code2, arg2);
3846 return build_indirect_ref (arg1, "unary *");
3851 case TRUNC_DIV_EXPR:
3862 case TRUNC_MOD_EXPR:
3866 case TRUTH_ANDIF_EXPR:
3867 case TRUTH_ORIF_EXPR:
3868 return cp_build_binary_op (code, arg1, arg2);
3873 case TRUTH_NOT_EXPR:
3874 case PREINCREMENT_EXPR:
3875 case POSTINCREMENT_EXPR:
3876 case PREDECREMENT_EXPR:
3877 case POSTDECREMENT_EXPR:
3880 return build_unary_op (code, arg1, candidates != 0);
3883 return build_array_ref (arg1, arg2);
3886 return build_conditional_expr (arg1, arg2, arg3);
3889 return build_m_component_ref (build_indirect_ref (arg1, NULL), arg2);
3891 /* The caller will deal with these. */
3903 /* Build a call to operator delete. This has to be handled very specially,
3904 because the restrictions on what signatures match are different from all
3905 other call instances. For a normal delete, only a delete taking (void *)
3906 or (void *, size_t) is accepted. For a placement delete, only an exact
3907 match with the placement new is accepted.
3909 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3910 ADDR is the pointer to be deleted.
3911 SIZE is the size of the memory block to be deleted.
3912 GLOBAL_P is true if the delete-expression should not consider
3913 class-specific delete operators.
3914 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3917 build_op_delete_call (enum tree_code code, tree addr, tree size,
3918 bool global_p, tree placement)
3920 tree fn = NULL_TREE;
3921 tree fns, fnname, argtypes, args, type;
3924 if (addr == error_mark_node)
3925 return error_mark_node;
3927 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3929 fnname = ansi_opname (code);
3931 if (IS_AGGR_TYPE (type) && !global_p)
3934 If the result of the lookup is ambiguous or inaccessible, or if
3935 the lookup selects a placement deallocation function, the
3936 program is ill-formed.
3938 Therefore, we ask lookup_fnfields to complain about ambiguity. */
3940 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3941 if (fns == error_mark_node)
3942 return error_mark_node;
3947 if (fns == NULL_TREE)
3948 fns = lookup_name_nonclass (fnname);
3955 /* Find the allocation function that is being called. */
3956 call_expr = placement;
3957 /* Extract the function. */
3958 alloc_fn = get_callee_fndecl (call_expr);
3959 my_friendly_assert (alloc_fn != NULL_TREE, 20020327);
3960 /* Then the second parm type. */
3961 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3962 /* Also the second argument. */
3963 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3967 /* First try it without the size argument. */
3968 argtypes = void_list_node;
3972 /* Strip const and volatile from addr. */
3973 addr = cp_convert (ptr_type_node, addr);
3975 /* We make two tries at finding a matching `operator delete'. On
3976 the first pass, we look for a one-operator (or placement)
3977 operator delete. If we're not doing placement delete, then on
3978 the second pass we look for a two-argument delete. */
3979 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
3981 /* Go through the `operator delete' functions looking for one
3982 with a matching type. */
3983 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
3989 /* The first argument must be "void *". */
3990 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
3991 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
3994 /* On the first pass, check the rest of the arguments. */
4000 if (!same_type_p (TREE_VALUE (a), TREE_VALUE (t)))
4008 /* On the second pass, the second argument must be
4011 && same_type_p (TREE_VALUE (t), sizetype)
4012 && TREE_CHAIN (t) == void_list_node)
4016 /* If we found a match, we're done. */
4021 /* If we have a matching function, call it. */
4024 /* Make sure we have the actual function, and not an
4026 fn = OVL_CURRENT (fn);
4028 /* If the FN is a member function, make sure that it is
4030 if (DECL_CLASS_SCOPE_P (fn))
4031 perform_or_defer_access_check (TYPE_BINFO (type), fn);
4034 args = tree_cons (NULL_TREE, addr, args);
4036 args = tree_cons (NULL_TREE, addr,
4037 build_tree_list (NULL_TREE, size));
4041 /* The placement args might not be suitable for overload
4042 resolution at this point, so build the call directly. */
4044 return build_cxx_call (fn, args);
4047 return build_function_call (fn, args);
4050 /* If we are doing placement delete we do nothing if we don't find a
4051 matching op delete. */
4055 error ("no suitable `operator %s' for `%T'",
4056 operator_name_info[(int)code].name, type);
4057 return error_mark_node;
4060 /* If the current scope isn't allowed to access DECL along
4061 BASETYPE_PATH, give an error. The most derived class in
4062 BASETYPE_PATH is the one used to qualify DECL. */
4065 enforce_access (tree basetype_path, tree decl)
4067 my_friendly_assert (TREE_CODE (basetype_path) == TREE_BINFO, 20030624);
4069 if (!accessible_p (basetype_path, decl))
4071 if (TREE_PRIVATE (decl))
4072 cp_error_at ("`%+#D' is private", decl);
4073 else if (TREE_PROTECTED (decl))
4074 cp_error_at ("`%+#D' is protected", decl);
4076 cp_error_at ("`%+#D' is inaccessible", decl);
4077 error ("within this context");
4084 /* Check that a callable constructor to initialize a temporary of
4085 TYPE from an EXPR exists. */
4088 check_constructor_callable (tree type, tree expr)
4090 build_special_member_call (NULL_TREE,
4091 complete_ctor_identifier,
4092 build_tree_list (NULL_TREE, expr),
4094 LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING
4095 | LOOKUP_CONSTRUCTOR_CALLABLE);
4098 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4099 bitwise or of LOOKUP_* values. If any errors are warnings are
4100 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4101 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4105 build_temp (tree expr, tree type, int flags,
4106 void (**diagnostic_fn)(const char *, ...))
4110 savew = warningcount, savee = errorcount;
4111 expr = build_special_member_call (NULL_TREE,
4112 complete_ctor_identifier,
4113 build_tree_list (NULL_TREE, expr),
4115 if (warningcount > savew)
4116 *diagnostic_fn = warning;
4117 else if (errorcount > savee)
4118 *diagnostic_fn = error;
4120 *diagnostic_fn = NULL;
4125 /* Perform the conversions in CONVS on the expression EXPR. FN and
4126 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4127 indicates the `this' argument of a method. INNER is nonzero when
4128 being called to continue a conversion chain. It is negative when a
4129 reference binding will be applied, positive otherwise. If
4130 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4131 conversions will be emitted if appropriate. */
4134 convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
4135 int inner, bool issue_conversion_warnings)
4137 tree totype = convs->type;
4138 void (*diagnostic_fn)(const char *, ...);
4141 && convs->kind != ck_user
4142 && convs->kind != ck_ambig
4143 && convs->kind != ck_ref_bind)
4145 conversion *t = convs;
4146 for (; t; t = convs->u.next)
4148 if (t->kind == ck_user || !t->bad_p)
4150 expr = convert_like_real (t, expr, fn, argnum, 1,
4151 /*issue_conversion_warnings=*/false);
4154 else if (t->kind == ck_ambig)
4155 return convert_like_real (t, expr, fn, argnum, 1,
4156 /*issue_conversion_warnings=*/false);
4157 else if (t->kind == ck_identity)
4160 pedwarn ("invalid conversion from `%T' to `%T'", TREE_TYPE (expr), totype);
4162 pedwarn (" initializing argument %P of `%D'", argnum, fn);
4163 return cp_convert (totype, expr);
4166 if (issue_conversion_warnings)
4167 expr = dubious_conversion_warnings
4168 (totype, expr, "converting", fn, argnum);
4169 switch (convs->kind)
4173 struct z_candidate *cand = convs->cand;
4174 tree convfn = cand->fn;
4177 if (DECL_CONSTRUCTOR_P (convfn))
4179 tree t = build_int_2 (0, 0);
4180 TREE_TYPE (t) = build_pointer_type (DECL_CONTEXT (convfn));
4182 args = build_tree_list (NULL_TREE, expr);
4183 if (DECL_HAS_IN_CHARGE_PARM_P (convfn)
4184 || DECL_HAS_VTT_PARM_P (convfn))
4185 /* We should never try to call the abstract or base constructor
4188 args = tree_cons (NULL_TREE, t, args);
4191 args = build_this (expr);
4192 expr = build_over_call (cand, LOOKUP_NORMAL);
4194 /* If this is a constructor or a function returning an aggr type,
4195 we need to build up a TARGET_EXPR. */
4196 if (DECL_CONSTRUCTOR_P (convfn))
4197 expr = build_cplus_new (totype, expr);
4199 /* The result of the call is then used to direct-initialize the object
4200 that is the destination of the copy-initialization. [dcl.init]
4202 Note that this step is not reflected in the conversion sequence;
4203 it affects the semantics when we actually perform the
4204 conversion, but is not considered during overload resolution.
4206 If the target is a class, that means call a ctor. */
4207 if (IS_AGGR_TYPE (totype)
4208 && (inner >= 0 || !lvalue_p (expr)))
4212 /* Core issue 84, now a DR, says that we don't
4213 allow UDCs for these args (which deliberately
4214 breaks copy-init of an auto_ptr<Base> from an
4215 auto_ptr<Derived>). */
4216 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION,
4223 (" initializing argument %P of `%D' from result of `%D'",
4224 argnum, fn, convfn);
4227 (" initializing temporary from result of `%D'", convfn);
4229 expr = build_cplus_new (totype, expr);
4234 if (type_unknown_p (expr))
4235 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4236 /* Convert a non-array constant variable to its underlying value, unless we
4237 are about to bind it to a reference, in which case we need to
4238 leave it as an lvalue. */
4240 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
4241 expr = decl_constant_value (expr);
4242 if (convs->check_copy_constructor_p)
4243 check_constructor_callable (totype, expr);
4246 /* Call build_user_type_conversion again for the error. */
4247 return build_user_type_conversion
4248 (totype, convs->u.expr, LOOKUP_NORMAL);
4254 expr = convert_like_real (convs->u.next, expr, fn, argnum,
4255 convs->kind == ck_ref_bind ? -1 : 1,
4256 /*issue_conversion_warnings=*/false);
4257 if (expr == error_mark_node)
4258 return error_mark_node;
4260 switch (convs->kind)
4263 if (! IS_AGGR_TYPE (totype))
4265 /* Else fall through. */
4267 if (convs->kind == ck_base && !convs->need_temporary_p)
4269 /* We are going to bind a reference directly to a base-class
4270 subobject of EXPR. */
4271 if (convs->check_copy_constructor_p)
4272 check_constructor_callable (TREE_TYPE (expr), expr);
4273 /* Build an expression for `*((base*) &expr)'. */
4274 expr = build_unary_op (ADDR_EXPR, expr, 0);
4275 expr = perform_implicit_conversion (build_pointer_type (totype),
4277 expr = build_indirect_ref (expr, "implicit conversion");
4281 /* Copy-initialization where the cv-unqualified version of the source
4282 type is the same class as, or a derived class of, the class of the
4283 destination [is treated as direct-initialization]. [dcl.init] */
4284 expr = build_temp (expr, totype, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
4286 if (diagnostic_fn && fn)
4287 diagnostic_fn (" initializing argument %P of `%D'", argnum, fn);
4288 return build_cplus_new (totype, expr);
4292 tree ref_type = totype;
4294 /* If necessary, create a temporary. */
4295 if (convs->need_temporary_p || !lvalue_p (expr))
4297 tree type = convs->u.next->type;
4299 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
4301 /* If the reference is volatile or non-const, we
4302 cannot create a temporary. */
4303 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4305 if (lvalue & clk_bitfield)
4306 error ("cannot bind bitfield `%E' to `%T'",
4308 else if (lvalue & clk_packed)
4309 error ("cannot bind packed field `%E' to `%T'",
4312 error ("cannot bind rvalue `%E' to `%T'", expr, ref_type);
4313 return error_mark_node;
4315 expr = build_target_expr_with_type (expr, type);
4318 /* Take the address of the thing to which we will bind the
4320 expr = build_unary_op (ADDR_EXPR, expr, 1);
4321 if (expr == error_mark_node)
4322 return error_mark_node;
4324 /* Convert it to a pointer to the type referred to by the
4325 reference. This will adjust the pointer if a derived to
4326 base conversion is being performed. */
4327 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4329 /* Convert the pointer to the desired reference type. */
4330 return build_nop (ref_type, expr);
4334 return decay_conversion (expr);
4337 /* Warn about deprecated conversion if appropriate. */
4338 string_conv_p (totype, expr, 1);
4344 return ocp_convert (totype, expr, CONV_IMPLICIT,
4345 LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
4348 /* Build a call to __builtin_trap. */
4351 call_builtin_trap (void)
4353 tree fn = implicit_built_in_decls[BUILT_IN_TRAP];
4355 my_friendly_assert (fn != NULL, 20030927);
4356 fn = build_call (fn, NULL_TREE);
4360 /* ARG is being passed to a varargs function. Perform any conversions
4361 required. Return the converted value. */
4364 convert_arg_to_ellipsis (tree arg)
4368 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4369 standard conversions are performed. */
4370 arg = decay_conversion (arg);
4373 If the argument has integral or enumeration type that is subject
4374 to the integral promotions (_conv.prom_), or a floating point
4375 type that is subject to the floating point promotion
4376 (_conv.fpprom_), the value of the argument is converted to the
4377 promoted type before the call. */
4378 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4379 && (TYPE_PRECISION (TREE_TYPE (arg))
4380 < TYPE_PRECISION (double_type_node)))
4381 arg = convert_to_real (double_type_node, arg);
4382 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4383 arg = perform_integral_promotions (arg);
4385 arg = require_complete_type (arg);
4387 if (arg != error_mark_node
4388 && !pod_type_p (TREE_TYPE (arg)))
4390 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4391 here and do a bitwise copy, but now cp_expr_size will abort if we
4393 If the call appears in the context of a sizeof expression,
4394 there is no need to emit a warning, since the expression won't be
4395 evaluated. We keep the builtin_trap just as a safety check. */
4396 if (!skip_evaluation)
4397 warning ("cannot pass objects of non-POD type `%#T' through `...'; "
4398 "call will abort at runtime", TREE_TYPE (arg));
4399 arg = call_builtin_trap ();
4400 arg = build (COMPOUND_EXPR, integer_type_node, arg,
4407 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4410 build_x_va_arg (tree expr, tree type)
4412 if (processing_template_decl)
4413 return build_min (VA_ARG_EXPR, type, expr);
4415 type = complete_type_or_else (type, NULL_TREE);
4417 if (expr == error_mark_node || !type)
4418 return error_mark_node;
4420 if (! pod_type_p (type))
4422 /* Undefined behavior [expr.call] 5.2.2/7. */
4423 warning ("cannot receive objects of non-POD type `%#T' through `...'; \
4424 call will abort at runtime",
4426 expr = convert (build_pointer_type (type), null_node);
4427 expr = build (COMPOUND_EXPR, TREE_TYPE (expr),
4428 call_builtin_trap (), expr);
4429 expr = build_indirect_ref (expr, NULL);
4433 return build_va_arg (expr, type);
4436 /* TYPE has been given to va_arg. Apply the default conversions which
4437 would have happened when passed via ellipsis. Return the promoted
4438 type, or the passed type if there is no change. */
4441 cxx_type_promotes_to (tree type)
4445 /* Perform the array-to-pointer and function-to-pointer
4447 type = type_decays_to (type);
4449 promote = type_promotes_to (type);
4450 if (same_type_p (type, promote))
4456 /* ARG is a default argument expression being passed to a parameter of
4457 the indicated TYPE, which is a parameter to FN. Do any required
4458 conversions. Return the converted value. */
4461 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4463 /* If the ARG is an unparsed default argument expression, the
4464 conversion cannot be performed. */
4465 if (TREE_CODE (arg) == DEFAULT_ARG)
4467 error ("the default argument for parameter %d of `%D' has "
4468 "not yet been parsed",
4470 return error_mark_node;
4473 if (fn && DECL_TEMPLATE_INFO (fn))
4474 arg = tsubst_default_argument (fn, type, arg);
4476 arg = break_out_target_exprs (arg);
4478 if (TREE_CODE (arg) == CONSTRUCTOR)
4480 arg = digest_init (type, arg, 0);
4481 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4482 "default argument", fn, parmnum);
4486 /* This could get clobbered by the following call. */
4487 if (TREE_HAS_CONSTRUCTOR (arg))
4488 arg = copy_node (arg);
4490 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4491 "default argument", fn, parmnum);
4492 arg = convert_for_arg_passing (type, arg);
4498 /* Returns the type which will really be used for passing an argument of
4502 type_passed_as (tree type)
4504 /* Pass classes with copy ctors by invisible reference. */
4505 if (TREE_ADDRESSABLE (type))
4507 type = build_reference_type (type);
4508 /* There are no other pointers to this temporary. */
4509 type = build_qualified_type (type, TYPE_QUAL_RESTRICT);
4511 else if (targetm.calls.promote_prototypes (type)
4512 && INTEGRAL_TYPE_P (type)
4513 && COMPLETE_TYPE_P (type)
4514 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4515 TYPE_SIZE (integer_type_node)))
4516 type = integer_type_node;
4521 /* Actually perform the appropriate conversion. */
4524 convert_for_arg_passing (tree type, tree val)
4526 if (val == error_mark_node)
4528 /* Pass classes with copy ctors by invisible reference. */
4529 else if (TREE_ADDRESSABLE (type))
4530 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4531 else if (targetm.calls.promote_prototypes (type)
4532 && INTEGRAL_TYPE_P (type)
4533 && COMPLETE_TYPE_P (type)
4534 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4535 TYPE_SIZE (integer_type_node)))
4536 val = perform_integral_promotions (val);
4540 /* Returns true iff FN is a function with magic varargs, i.e. ones for
4541 which no conversions at all should be done. This is true for some
4542 builtins which don't act like normal functions. */
4545 magic_varargs_p (tree fn)
4547 if (DECL_BUILT_IN (fn))
4548 switch (DECL_FUNCTION_CODE (fn))
4550 case BUILT_IN_CLASSIFY_TYPE:
4551 case BUILT_IN_CONSTANT_P:
4552 case BUILT_IN_NEXT_ARG:
4553 case BUILT_IN_STDARG_START:
4554 case BUILT_IN_VA_START:
4563 /* Subroutine of the various build_*_call functions. Overload resolution
4564 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4565 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4566 bitmask of various LOOKUP_* flags which apply to the call itself. */
4569 build_over_call (struct z_candidate *cand, int flags)
4572 tree args = cand->args;
4573 conversion **convs = cand->convs;
4575 tree converted_args = NULL_TREE;
4576 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4581 /* In a template, there is no need to perform all of the work that
4582 is normally done. We are only interested in the type of the call
4583 expression, i.e., the return type of the function. Any semantic
4584 errors will be deferred until the template is instantiated. */
4585 if (processing_template_decl)
4589 return_type = TREE_TYPE (TREE_TYPE (fn));
4590 expr = build (CALL_EXPR, return_type, fn, args, NULL_TREE);
4591 if (TREE_THIS_VOLATILE (fn) && cfun)
4592 current_function_returns_abnormally = 1;
4593 if (!VOID_TYPE_P (return_type))
4594 require_complete_type (return_type);
4595 return convert_from_reference (expr);
4598 /* Give any warnings we noticed during overload resolution. */
4601 struct candidate_warning *w;
4602 for (w = cand->warnings; w; w = w->next)
4603 joust (cand, w->loser, 1);
4606 if (DECL_FUNCTION_MEMBER_P (fn))
4608 /* If FN is a template function, two cases must be considered.
4613 template <class T> void f();
4615 template <class T> struct B {
4619 struct C : A, B<int> {
4621 using B<int>::g; // #2
4624 In case #1 where `A::f' is a member template, DECL_ACCESS is
4625 recorded in the primary template but not in its specialization.
4626 We check access of FN using its primary template.
4628 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
4629 because it is a member of class template B, DECL_ACCESS is
4630 recorded in the specialization `B<int>::g'. We cannot use its
4631 primary template because `B<T>::g' and `B<int>::g' may have
4632 different access. */
4633 if (DECL_TEMPLATE_INFO (fn)
4634 && is_member_template (DECL_TI_TEMPLATE (fn)))
4635 perform_or_defer_access_check (cand->access_path,
4636 DECL_TI_TEMPLATE (fn));
4638 perform_or_defer_access_check (cand->access_path, fn);
4641 if (args && TREE_CODE (args) != TREE_LIST)
4642 args = build_tree_list (NULL_TREE, args);
4645 /* The implicit parameters to a constructor are not considered by overload
4646 resolution, and must be of the proper type. */
4647 if (DECL_CONSTRUCTOR_P (fn))
4649 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4650 arg = TREE_CHAIN (arg);
4651 parm = TREE_CHAIN (parm);
4652 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
4653 /* We should never try to call the abstract constructor. */
4655 if (DECL_HAS_VTT_PARM_P (fn))
4657 converted_args = tree_cons
4658 (NULL_TREE, TREE_VALUE (arg), converted_args);
4659 arg = TREE_CHAIN (arg);
4660 parm = TREE_CHAIN (parm);
4663 /* Bypass access control for 'this' parameter. */
4664 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4666 tree parmtype = TREE_VALUE (parm);
4667 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4671 if (convs[i]->bad_p)
4672 pedwarn ("passing `%T' as `this' argument of `%#D' discards qualifiers",
4673 TREE_TYPE (argtype), fn);
4675 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4676 X is called for an object that is not of type X, or of a type
4677 derived from X, the behavior is undefined.
4679 So we can assume that anything passed as 'this' is non-null, and
4680 optimize accordingly. */
4681 my_friendly_assert (TREE_CODE (parmtype) == POINTER_TYPE, 19990811);
4682 /* Convert to the base in which the function was declared. */
4683 my_friendly_assert (cand->conversion_path != NULL_TREE, 20020730);
4684 converted_arg = build_base_path (PLUS_EXPR,
4686 cand->conversion_path,
4688 /* Check that the base class is accessible. */
4689 if (!accessible_base_p (TREE_TYPE (argtype),
4690 BINFO_TYPE (cand->conversion_path)))
4691 error ("`%T' is not an accessible base of `%T'",
4692 BINFO_TYPE (cand->conversion_path),
4693 TREE_TYPE (argtype));
4694 /* If fn was found by a using declaration, the conversion path
4695 will be to the derived class, not the base declaring fn. We
4696 must convert from derived to base. */
4697 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4698 TREE_TYPE (parmtype), ba_ignore, NULL);
4699 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4702 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4703 parm = TREE_CHAIN (parm);
4704 arg = TREE_CHAIN (arg);
4710 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4712 tree type = TREE_VALUE (parm);
4715 val = convert_like_with_context
4716 (conv, TREE_VALUE (arg), fn, i - is_method);
4718 val = convert_for_arg_passing (type, val);
4719 converted_args = tree_cons (NULL_TREE, val, converted_args);
4722 /* Default arguments */
4723 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4725 = tree_cons (NULL_TREE,
4726 convert_default_arg (TREE_VALUE (parm),
4727 TREE_PURPOSE (parm),
4732 for (; arg; arg = TREE_CHAIN (arg))
4734 tree a = TREE_VALUE (arg);
4735 if (magic_varargs_p (fn))
4736 /* Do no conversions for magic varargs. */;
4738 a = convert_arg_to_ellipsis (a);
4739 converted_args = tree_cons (NULL_TREE, a, converted_args);
4742 converted_args = nreverse (converted_args);
4744 check_function_arguments (TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4747 /* Avoid actually calling copy constructors and copy assignment operators,
4750 if (! flag_elide_constructors)
4751 /* Do things the hard way. */;
4752 else if (cand->num_convs == 1 && DECL_COPY_CONSTRUCTOR_P (fn))
4755 arg = skip_artificial_parms_for (fn, converted_args);
4756 arg = TREE_VALUE (arg);
4758 /* Pull out the real argument, disregarding const-correctness. */
4760 while (TREE_CODE (targ) == NOP_EXPR
4761 || TREE_CODE (targ) == NON_LVALUE_EXPR
4762 || TREE_CODE (targ) == CONVERT_EXPR)
4763 targ = TREE_OPERAND (targ, 0);
4764 if (TREE_CODE (targ) == ADDR_EXPR)
4766 targ = TREE_OPERAND (targ, 0);
4767 if (!same_type_ignoring_top_level_qualifiers_p
4768 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4777 arg = build_indirect_ref (arg, 0);
4779 /* [class.copy]: the copy constructor is implicitly defined even if
4780 the implementation elided its use. */
4781 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4784 /* If we're creating a temp and we already have one, don't create a
4785 new one. If we're not creating a temp but we get one, use
4786 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4787 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4788 temp or an INIT_EXPR otherwise. */
4789 if (integer_zerop (TREE_VALUE (args)))
4791 if (TREE_CODE (arg) == TARGET_EXPR)
4793 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4794 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4796 else if (TREE_CODE (arg) == TARGET_EXPR
4797 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4799 tree to = stabilize_reference
4800 (build_indirect_ref (TREE_VALUE (args), 0));
4802 val = build (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4806 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4808 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4810 tree to = stabilize_reference
4811 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4812 tree type = TREE_TYPE (to);
4813 tree as_base = CLASSTYPE_AS_BASE (type);
4815 arg = TREE_VALUE (TREE_CHAIN (converted_args));
4816 if (tree_int_cst_equal (TYPE_SIZE (type), TYPE_SIZE (as_base)))
4818 arg = build_indirect_ref (arg, 0);
4819 val = build (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4823 /* We must only copy the non-tail padding parts.
4824 Use __builtin_memcpy for the bitwise copy. */
4828 args = tree_cons (NULL, TYPE_SIZE_UNIT (as_base), NULL);
4829 args = tree_cons (NULL, arg, args);
4830 t = build_unary_op (ADDR_EXPR, to, 0);
4831 args = tree_cons (NULL, t, args);
4832 t = implicit_built_in_decls[BUILT_IN_MEMCPY];
4833 t = build_call (t, args);
4835 t = convert (TREE_TYPE (TREE_VALUE (args)), t);
4836 val = build_indirect_ref (t, 0);
4844 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4846 tree t, *p = &TREE_VALUE (converted_args);
4847 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4850 my_friendly_assert (binfo && binfo != error_mark_node, 20010730);
4852 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4853 if (TREE_SIDE_EFFECTS (*p))
4854 *p = save_expr (*p);
4855 t = build_pointer_type (TREE_TYPE (fn));
4856 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4857 fn = build_java_interface_fn_ref (fn, *p);
4859 fn = build_vfn_ref (*p, DECL_VINDEX (fn));
4862 else if (DECL_INLINE (fn))
4863 fn = inline_conversion (fn);
4865 fn = build_addr_func (fn);
4867 return build_cxx_call (fn, converted_args);
4870 /* Build and return a call to FN, using ARGS. This function performs
4871 no overload resolution, conversion, or other high-level
4875 build_cxx_call (tree fn, tree args)
4879 fn = build_call (fn, args);
4881 /* If this call might throw an exception, note that fact. */
4882 fndecl = get_callee_fndecl (fn);
4883 if ((!fndecl || !TREE_NOTHROW (fndecl))
4884 && at_function_scope_p ()
4886 cp_function_chain->can_throw = 1;
4888 /* Some built-in function calls will be evaluated at compile-time in
4892 if (VOID_TYPE_P (TREE_TYPE (fn)))
4895 fn = require_complete_type (fn);
4896 if (fn == error_mark_node)
4897 return error_mark_node;
4899 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4900 fn = build_cplus_new (TREE_TYPE (fn), fn);
4901 return convert_from_reference (fn);
4904 static GTY(()) tree java_iface_lookup_fn;
4906 /* Make an expression which yields the address of the Java interface
4907 method FN. This is achieved by generating a call to libjava's
4908 _Jv_LookupInterfaceMethodIdx(). */
4911 build_java_interface_fn_ref (tree fn, tree instance)
4913 tree lookup_args, lookup_fn, method, idx;
4914 tree klass_ref, iface, iface_ref;
4917 if (!java_iface_lookup_fn)
4919 tree endlink = build_void_list_node ();
4920 tree t = tree_cons (NULL_TREE, ptr_type_node,
4921 tree_cons (NULL_TREE, ptr_type_node,
4922 tree_cons (NULL_TREE, java_int_type_node,
4924 java_iface_lookup_fn
4925 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
4926 build_function_type (ptr_type_node, t),
4927 0, NOT_BUILT_IN, NULL, NULL_TREE);
4930 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
4931 This is the first entry in the vtable. */
4932 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
4935 /* Get the java.lang.Class pointer for the interface being called. */
4936 iface = DECL_CONTEXT (fn);
4937 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
4938 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
4939 || DECL_CONTEXT (iface_ref) != iface)
4941 error ("could not find class$ field in java interface type `%T'",
4943 return error_mark_node;
4945 iface_ref = build_address (iface_ref);
4946 iface_ref = convert (build_pointer_type (iface), iface_ref);
4948 /* Determine the itable index of FN. */
4950 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
4952 if (!DECL_VIRTUAL_P (method))
4958 idx = build_int_2 (i, 0);
4960 lookup_args = tree_cons (NULL_TREE, klass_ref,
4961 tree_cons (NULL_TREE, iface_ref,
4962 build_tree_list (NULL_TREE, idx)));
4963 lookup_fn = build1 (ADDR_EXPR,
4964 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
4965 java_iface_lookup_fn);
4966 return build (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
4969 /* Returns the value to use for the in-charge parameter when making a
4970 call to a function with the indicated NAME. */
4973 in_charge_arg_for_name (tree name)
4975 if (name == base_ctor_identifier
4976 || name == base_dtor_identifier)
4977 return integer_zero_node;
4978 else if (name == complete_ctor_identifier)
4979 return integer_one_node;
4980 else if (name == complete_dtor_identifier)
4981 return integer_two_node;
4982 else if (name == deleting_dtor_identifier)
4983 return integer_three_node;
4985 /* This function should only be called with one of the names listed
4991 /* Build a call to a constructor, destructor, or an assignment
4992 operator for INSTANCE, an expression with class type. NAME
4993 indicates the special member function to call; ARGS are the
4994 arguments. BINFO indicates the base of INSTANCE that is to be
4995 passed as the `this' parameter to the member function called.
4997 FLAGS are the LOOKUP_* flags to use when processing the call.
4999 If NAME indicates a complete object constructor, INSTANCE may be
5000 NULL_TREE. In this case, the caller will call build_cplus_new to
5001 store the newly constructed object into a VAR_DECL. */
5004 build_special_member_call (tree instance, tree name, tree args,
5005 tree binfo, int flags)
5008 /* The type of the subobject to be constructed or destroyed. */
5011 my_friendly_assert (name == complete_ctor_identifier
5012 || name == base_ctor_identifier
5013 || name == complete_dtor_identifier
5014 || name == base_dtor_identifier
5015 || name == deleting_dtor_identifier
5016 || name == ansi_assopname (NOP_EXPR),
5020 /* Resolve the name. */
5021 if (!complete_type_or_else (binfo, NULL_TREE))
5022 return error_mark_node;
5024 binfo = TYPE_BINFO (binfo);
5027 my_friendly_assert (binfo != NULL_TREE, 20020712);
5029 class_type = BINFO_TYPE (binfo);
5031 /* Handle the special case where INSTANCE is NULL_TREE. */
5032 if (name == complete_ctor_identifier && !instance)
5034 instance = build_int_2 (0, 0);
5035 TREE_TYPE (instance) = build_pointer_type (class_type);
5036 instance = build1 (INDIRECT_REF, class_type, instance);
5040 if (name == complete_dtor_identifier
5041 || name == base_dtor_identifier
5042 || name == deleting_dtor_identifier)
5043 my_friendly_assert (args == NULL_TREE, 20020712);
5045 /* Convert to the base class, if necessary. */
5046 if (!same_type_ignoring_top_level_qualifiers_p
5047 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
5049 if (name != ansi_assopname (NOP_EXPR))
5050 /* For constructors and destructors, either the base is
5051 non-virtual, or it is virtual but we are doing the
5052 conversion from a constructor or destructor for the
5053 complete object. In either case, we can convert
5055 instance = convert_to_base_statically (instance, binfo);
5057 /* However, for assignment operators, we must convert
5058 dynamically if the base is virtual. */
5059 instance = build_base_path (PLUS_EXPR, instance,
5060 binfo, /*nonnull=*/1);
5064 my_friendly_assert (instance != NULL_TREE, 20020712);
5066 fns = lookup_fnfields (binfo, name, 1);
5068 /* When making a call to a constructor or destructor for a subobject
5069 that uses virtual base classes, pass down a pointer to a VTT for
5071 if ((name == base_ctor_identifier
5072 || name == base_dtor_identifier)
5073 && TYPE_USES_VIRTUAL_BASECLASSES (class_type))
5078 /* If the current function is a complete object constructor
5079 or destructor, then we fetch the VTT directly.
5080 Otherwise, we look it up using the VTT we were given. */
5081 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
5082 vtt = decay_conversion (vtt);
5083 vtt = build (COND_EXPR, TREE_TYPE (vtt),
5084 build (EQ_EXPR, boolean_type_node,
5085 current_in_charge_parm, integer_zero_node),
5088 my_friendly_assert (BINFO_SUBVTT_INDEX (binfo), 20010110);
5089 sub_vtt = build (PLUS_EXPR, TREE_TYPE (vtt), vtt,
5090 BINFO_SUBVTT_INDEX (binfo));
5092 args = tree_cons (NULL_TREE, sub_vtt, args);
5095 return build_new_method_call (instance, fns, args,
5096 TYPE_BINFO (BINFO_TYPE (binfo)),
5100 /* Return the NAME, as a C string. The NAME indicates a function that
5101 is a member of TYPE. *FREE_P is set to true if the caller must
5102 free the memory returned.
5104 Rather than go through all of this, we should simply set the names
5105 of constructors and destructors appropriately, and dispense with
5106 ctor_identifier, dtor_identifier, etc. */
5109 name_as_c_string (tree name, tree type, bool *free_p)
5113 /* Assume that we will not allocate memory. */
5115 /* Constructors and destructors are special. */
5116 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5119 = (char *) IDENTIFIER_POINTER (constructor_name (type));
5120 /* For a destructor, add the '~'. */
5121 if (name == complete_dtor_identifier
5122 || name == base_dtor_identifier
5123 || name == deleting_dtor_identifier)
5125 pretty_name = concat ("~", pretty_name, NULL);
5126 /* Remember that we need to free the memory allocated. */
5130 else if (IDENTIFIER_TYPENAME_P (name))
5132 pretty_name = concat ("operator ",
5133 type_as_string (TREE_TYPE (name),
5134 TFF_PLAIN_IDENTIFIER),
5136 /* Remember that we need to free the memory allocated. */
5140 pretty_name = (char *) IDENTIFIER_POINTER (name);
5145 /* Build a call to "INSTANCE.FN (ARGS)". */
5148 build_new_method_call (tree instance, tree fns, tree args,
5149 tree conversion_path, int flags)
5151 struct z_candidate *candidates = 0, *cand;
5152 tree explicit_targs = NULL_TREE;
5153 tree basetype = NULL_TREE;
5156 tree mem_args = NULL_TREE, instance_ptr;
5162 int template_only = 0;
5169 my_friendly_assert (instance != NULL_TREE, 20020729);
5171 if (error_operand_p (instance)
5172 || error_operand_p (fns)
5173 || args == error_mark_node)
5174 return error_mark_node;
5176 orig_instance = instance;
5180 if (processing_template_decl)
5182 instance = build_non_dependent_expr (instance);
5183 if (!BASELINK_P (fns)
5184 && TREE_CODE (fns) != PSEUDO_DTOR_EXPR
5185 && TREE_TYPE (fns) != unknown_type_node)
5186 fns = build_non_dependent_expr (fns);
5187 args = build_non_dependent_args (orig_args);
5190 /* Process the argument list. */
5192 args = resolve_args (args);
5193 if (args == error_mark_node)
5194 return error_mark_node;
5196 if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
5197 instance = convert_from_reference (instance);
5198 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
5199 instance_ptr = build_this (instance);
5201 if (!BASELINK_P (fns))
5203 error ("call to non-function `%D'", fns);
5204 return error_mark_node;
5207 if (!conversion_path)
5208 conversion_path = BASELINK_BINFO (fns);
5209 access_binfo = BASELINK_ACCESS_BINFO (fns);
5210 optype = BASELINK_OPTYPE (fns);
5211 fns = BASELINK_FUNCTIONS (fns);
5213 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
5215 explicit_targs = TREE_OPERAND (fns, 1);
5216 fns = TREE_OPERAND (fns, 0);
5220 my_friendly_assert (TREE_CODE (fns) == FUNCTION_DECL
5221 || TREE_CODE (fns) == TEMPLATE_DECL
5222 || TREE_CODE (fns) == OVERLOAD,
5225 /* XXX this should be handled before we get here. */
5226 if (! IS_AGGR_TYPE (basetype))
5228 if ((flags & LOOKUP_COMPLAIN) && basetype != error_mark_node)
5229 error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
5230 fns, instance, basetype);
5232 return error_mark_node;
5235 fn = get_first_fn (fns);
5236 name = DECL_NAME (fn);
5238 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
5240 /* Callers should explicitly indicate whether they want to construct
5241 the complete object or just the part without virtual bases. */
5242 my_friendly_assert (name != ctor_identifier, 20000408);
5243 /* Similarly for destructors. */
5244 my_friendly_assert (name != dtor_identifier, 20000408);
5247 /* It's OK to call destructors on cv-qualified objects. Therefore,
5248 convert the INSTANCE_PTR to the unqualified type, if necessary. */
5249 if (DECL_DESTRUCTOR_P (fn))
5251 tree type = build_pointer_type (basetype);
5252 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
5253 instance_ptr = build_nop (type, instance_ptr);
5256 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
5257 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
5259 /* Get the high-water mark for the CONVERSION_OBSTACK. */
5260 p = conversion_obstack_alloc (0);
5262 for (fn = fns; fn; fn = OVL_NEXT (fn))
5264 tree t = OVL_CURRENT (fn);
5267 /* We can end up here for copy-init of same or base class. */
5268 if ((flags & LOOKUP_ONLYCONVERTING)
5269 && DECL_NONCONVERTING_P (t))
5272 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
5273 this_arglist = mem_args;
5275 this_arglist = args;
5277 if (TREE_CODE (t) == TEMPLATE_DECL)
5278 /* A member template. */
5279 add_template_candidate (&candidates, t,
5282 this_arglist, optype,
5287 else if (! template_only)
5288 add_function_candidate (&candidates, t,
5296 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5299 if (!COMPLETE_TYPE_P (basetype))
5300 cxx_incomplete_type_error (instance_ptr, basetype);
5306 pretty_name = name_as_c_string (name, basetype, &free_p);
5307 error ("no matching function for call to `%T::%s(%A)%#V'",
5308 basetype, pretty_name, user_args,
5309 TREE_TYPE (TREE_TYPE (instance_ptr)));
5313 print_z_candidates (candidates);
5314 call = error_mark_node;
5318 cand = tourney (candidates);
5324 pretty_name = name_as_c_string (name, basetype, &free_p);
5325 error ("call of overloaded `%s(%A)' is ambiguous", pretty_name,
5327 print_z_candidates (candidates);
5330 call = error_mark_node;
5334 if (DECL_PURE_VIRTUAL_P (cand->fn)
5335 && instance == current_class_ref
5336 && (DECL_CONSTRUCTOR_P (current_function_decl)
5337 || DECL_DESTRUCTOR_P (current_function_decl))
5338 && ! (flags & LOOKUP_NONVIRTUAL)
5339 && value_member (cand->fn, CLASSTYPE_PURE_VIRTUALS (basetype)))
5340 error ((DECL_CONSTRUCTOR_P (current_function_decl) ?
5341 "abstract virtual `%#D' called from constructor"
5342 : "abstract virtual `%#D' called from destructor"),
5344 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5345 && is_dummy_object (instance_ptr))
5347 error ("cannot call member function `%D' without object",
5349 call = error_mark_node;
5353 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5354 && resolves_to_fixed_type_p (instance, 0))
5355 flags |= LOOKUP_NONVIRTUAL;
5357 call = build_over_call (cand, flags);
5359 /* In an expression of the form `a->f()' where `f' turns
5360 out to be a static member function, `a' is
5361 none-the-less evaluated. */
5362 if (TREE_CODE (TREE_TYPE (cand->fn)) != METHOD_TYPE
5363 && !is_dummy_object (instance_ptr)
5364 && TREE_SIDE_EFFECTS (instance))
5365 call = build (COMPOUND_EXPR, TREE_TYPE (call),
5371 if (processing_template_decl && call != error_mark_node)
5372 call = (build_min_non_dep
5374 build_min_nt (COMPONENT_REF, orig_instance, orig_fns, NULL_TREE),
5375 orig_args, NULL_TREE));
5377 /* Free all the conversions we allocated. */
5378 obstack_free (&conversion_obstack, p);
5383 /* Returns true iff standard conversion sequence ICS1 is a proper
5384 subsequence of ICS2. */
5387 is_subseq (conversion *ics1, conversion *ics2)
5389 /* We can assume that a conversion of the same code
5390 between the same types indicates a subsequence since we only get
5391 here if the types we are converting from are the same. */
5393 while (ics1->kind == ck_rvalue
5394 || ics1->kind == ck_lvalue)
5395 ics1 = ics1->u.next;
5399 while (ics2->kind == ck_rvalue
5400 || ics2->kind == ck_lvalue)
5401 ics2 = ics2->u.next;
5403 if (ics2->kind == ck_user
5404 || ics2->kind == ck_ambig
5405 || ics2->kind == ck_identity)
5406 /* At this point, ICS1 cannot be a proper subsequence of
5407 ICS2. We can get a USER_CONV when we are comparing the
5408 second standard conversion sequence of two user conversion
5412 ics2 = ics2->u.next;
5414 if (ics2->kind == ics1->kind
5415 && same_type_p (ics2->type, ics1->type)
5416 && same_type_p (ics2->u.next->type,
5417 ics1->u.next->type))
5422 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5423 be any _TYPE nodes. */
5426 is_properly_derived_from (tree derived, tree base)
5428 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5429 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5432 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5433 considers every class derived from itself. */
5434 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5435 && DERIVED_FROM_P (base, derived));
5438 /* We build the ICS for an implicit object parameter as a pointer
5439 conversion sequence. However, such a sequence should be compared
5440 as if it were a reference conversion sequence. If ICS is the
5441 implicit conversion sequence for an implicit object parameter,
5442 modify it accordingly. */
5445 maybe_handle_implicit_object (conversion **ics)
5449 /* [over.match.funcs]
5451 For non-static member functions, the type of the
5452 implicit object parameter is "reference to cv X"
5453 where X is the class of which the function is a
5454 member and cv is the cv-qualification on the member
5455 function declaration. */
5456 conversion *t = *ics;
5457 tree reference_type;
5459 /* The `this' parameter is a pointer to a class type. Make the
5460 implicit conversion talk about a reference to that same class
5462 reference_type = TREE_TYPE (t->type);
5463 reference_type = build_reference_type (reference_type);
5465 if (t->kind == ck_qual)
5467 if (t->kind == ck_ptr)
5469 t = build_identity_conv (TREE_TYPE (t->type), NULL_TREE);
5470 t = direct_reference_binding (reference_type, t);
5475 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5476 and return the type to which the reference refers. Otherwise,
5477 leave *ICS unchanged and return NULL_TREE. */
5480 maybe_handle_ref_bind (conversion **ics)
5482 if ((*ics)->kind == ck_ref_bind)
5484 conversion *old_ics = *ics;
5485 tree type = TREE_TYPE (old_ics->type);
5486 *ics = old_ics->u.next;
5487 (*ics)->user_conv_p = old_ics->user_conv_p;
5488 (*ics)->bad_p = old_ics->bad_p;
5495 /* Compare two implicit conversion sequences according to the rules set out in
5496 [over.ics.rank]. Return values:
5498 1: ics1 is better than ics2
5499 -1: ics2 is better than ics1
5500 0: ics1 and ics2 are indistinguishable */
5503 compare_ics (conversion *ics1, conversion *ics2)
5509 tree deref_from_type1 = NULL_TREE;
5510 tree deref_from_type2 = NULL_TREE;
5511 tree deref_to_type1 = NULL_TREE;
5512 tree deref_to_type2 = NULL_TREE;
5513 conversion_rank rank1, rank2;
5515 /* REF_BINDING is nonzero if the result of the conversion sequence
5516 is a reference type. In that case TARGET_TYPE is the
5517 type referred to by the reference. */
5521 /* Handle implicit object parameters. */
5522 maybe_handle_implicit_object (&ics1);
5523 maybe_handle_implicit_object (&ics2);
5525 /* Handle reference parameters. */
5526 target_type1 = maybe_handle_ref_bind (&ics1);
5527 target_type2 = maybe_handle_ref_bind (&ics2);
5531 When comparing the basic forms of implicit conversion sequences (as
5532 defined in _over.best.ics_)
5534 --a standard conversion sequence (_over.ics.scs_) is a better
5535 conversion sequence than a user-defined conversion sequence
5536 or an ellipsis conversion sequence, and
5538 --a user-defined conversion sequence (_over.ics.user_) is a
5539 better conversion sequence than an ellipsis conversion sequence
5540 (_over.ics.ellipsis_). */
5541 rank1 = CONVERSION_RANK (ics1);
5542 rank2 = CONVERSION_RANK (ics2);
5546 else if (rank1 < rank2)
5549 if (rank1 == cr_bad)
5551 /* XXX Isn't this an extension? */
5552 /* Both ICS are bad. We try to make a decision based on what
5553 would have happened if they'd been good. */
5554 if (ics1->user_conv_p > ics2->user_conv_p
5555 || ics1->rank > ics2->rank)
5557 else if (ics1->user_conv_p < ics2->user_conv_p
5558 || ics1->rank < ics2->rank)
5561 /* We couldn't make up our minds; try to figure it out below. */
5564 if (ics1->ellipsis_p)
5565 /* Both conversions are ellipsis conversions. */
5568 /* User-defined conversion sequence U1 is a better conversion sequence
5569 than another user-defined conversion sequence U2 if they contain the
5570 same user-defined conversion operator or constructor and if the sec-
5571 ond standard conversion sequence of U1 is better than the second
5572 standard conversion sequence of U2. */
5574 if (ics1->user_conv_p)
5579 for (t1 = ics1; t1->kind != ck_user; t1 = t1->u.next)
5580 if (t1->kind == ck_ambig)
5582 for (t2 = ics2; t2->kind != ck_user; t2 = t2->u.next)
5583 if (t2->kind == ck_ambig)
5586 if (t1->cand->fn != t2->cand->fn)
5589 /* We can just fall through here, after setting up
5590 FROM_TYPE1 and FROM_TYPE2. */
5591 from_type1 = t1->type;
5592 from_type2 = t2->type;
5599 /* We're dealing with two standard conversion sequences.
5603 Standard conversion sequence S1 is a better conversion
5604 sequence than standard conversion sequence S2 if
5606 --S1 is a proper subsequence of S2 (comparing the conversion
5607 sequences in the canonical form defined by _over.ics.scs_,
5608 excluding any Lvalue Transformation; the identity
5609 conversion sequence is considered to be a subsequence of
5610 any non-identity conversion sequence */
5613 while (t1->kind != ck_identity)
5615 from_type1 = t1->type;
5618 while (t2->kind != ck_identity)
5620 from_type2 = t2->type;
5623 if (same_type_p (from_type1, from_type2))
5625 if (is_subseq (ics1, ics2))
5627 if (is_subseq (ics2, ics1))
5630 /* Otherwise, one sequence cannot be a subsequence of the other; they
5631 don't start with the same type. This can happen when comparing the
5632 second standard conversion sequence in two user-defined conversion
5639 --the rank of S1 is better than the rank of S2 (by the rules
5642 Standard conversion sequences are ordered by their ranks: an Exact
5643 Match is a better conversion than a Promotion, which is a better
5644 conversion than a Conversion.
5646 Two conversion sequences with the same rank are indistinguishable
5647 unless one of the following rules applies:
5649 --A conversion that is not a conversion of a pointer, or pointer
5650 to member, to bool is better than another conversion that is such
5653 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5654 so that we do not have to check it explicitly. */
5655 if (ics1->rank < ics2->rank)
5657 else if (ics2->rank < ics1->rank)
5660 to_type1 = ics1->type;
5661 to_type2 = ics2->type;
5663 if (TYPE_PTR_P (from_type1)
5664 && TYPE_PTR_P (from_type2)
5665 && TYPE_PTR_P (to_type1)
5666 && TYPE_PTR_P (to_type2))
5668 deref_from_type1 = TREE_TYPE (from_type1);
5669 deref_from_type2 = TREE_TYPE (from_type2);
5670 deref_to_type1 = TREE_TYPE (to_type1);
5671 deref_to_type2 = TREE_TYPE (to_type2);
5673 /* The rules for pointers to members A::* are just like the rules
5674 for pointers A*, except opposite: if B is derived from A then
5675 A::* converts to B::*, not vice versa. For that reason, we
5676 switch the from_ and to_ variables here. */
5677 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5678 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5679 || (TYPE_PTRMEMFUNC_P (from_type1)
5680 && TYPE_PTRMEMFUNC_P (from_type2)
5681 && TYPE_PTRMEMFUNC_P (to_type1)
5682 && TYPE_PTRMEMFUNC_P (to_type2)))
5684 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5685 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5686 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5687 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5690 if (deref_from_type1 != NULL_TREE
5691 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5692 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5694 /* This was one of the pointer or pointer-like conversions.
5698 --If class B is derived directly or indirectly from class A,
5699 conversion of B* to A* is better than conversion of B* to
5700 void*, and conversion of A* to void* is better than
5701 conversion of B* to void*. */
5702 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5703 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5705 if (is_properly_derived_from (deref_from_type1,
5708 else if (is_properly_derived_from (deref_from_type2,
5712 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5713 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5715 if (same_type_p (deref_from_type1, deref_from_type2))
5717 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5719 if (is_properly_derived_from (deref_from_type1,
5723 /* We know that DEREF_TO_TYPE1 is `void' here. */
5724 else if (is_properly_derived_from (deref_from_type1,
5729 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5730 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5734 --If class B is derived directly or indirectly from class A
5735 and class C is derived directly or indirectly from B,
5737 --conversion of C* to B* is better than conversion of C* to
5740 --conversion of B* to A* is better than conversion of C* to
5742 if (same_type_p (deref_from_type1, deref_from_type2))
5744 if (is_properly_derived_from (deref_to_type1,
5747 else if (is_properly_derived_from (deref_to_type2,
5751 else if (same_type_p (deref_to_type1, deref_to_type2))
5753 if (is_properly_derived_from (deref_from_type2,
5756 else if (is_properly_derived_from (deref_from_type1,
5762 else if (CLASS_TYPE_P (non_reference (from_type1))
5763 && same_type_p (from_type1, from_type2))
5765 tree from = non_reference (from_type1);
5769 --binding of an expression of type C to a reference of type
5770 B& is better than binding an expression of type C to a
5771 reference of type A&
5773 --conversion of C to B is better than conversion of C to A, */
5774 if (is_properly_derived_from (from, to_type1)
5775 && is_properly_derived_from (from, to_type2))
5777 if (is_properly_derived_from (to_type1, to_type2))
5779 else if (is_properly_derived_from (to_type2, to_type1))
5783 else if (CLASS_TYPE_P (non_reference (to_type1))
5784 && same_type_p (to_type1, to_type2))
5786 tree to = non_reference (to_type1);
5790 --binding of an expression of type B to a reference of type
5791 A& is better than binding an expression of type C to a
5792 reference of type A&,
5794 --conversion of B to A is better than conversion of C to A */
5795 if (is_properly_derived_from (from_type1, to)
5796 && is_properly_derived_from (from_type2, to))
5798 if (is_properly_derived_from (from_type2, from_type1))
5800 else if (is_properly_derived_from (from_type1, from_type2))
5807 --S1 and S2 differ only in their qualification conversion and yield
5808 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5809 qualification signature of type T1 is a proper subset of the cv-
5810 qualification signature of type T2 */
5811 if (ics1->kind == ck_qual
5812 && ics2->kind == ck_qual
5813 && same_type_p (from_type1, from_type2))
5814 return comp_cv_qual_signature (to_type1, to_type2);
5818 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5819 types to which the references refer are the same type except for
5820 top-level cv-qualifiers, and the type to which the reference
5821 initialized by S2 refers is more cv-qualified than the type to
5822 which the reference initialized by S1 refers */
5824 if (target_type1 && target_type2
5825 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5826 return comp_cv_qualification (target_type2, target_type1);
5828 /* Neither conversion sequence is better than the other. */
5832 /* The source type for this standard conversion sequence. */
5835 source_type (conversion *t)
5837 for (;; t = t->u.next)
5839 if (t->kind == ck_user
5840 || t->kind == ck_ambig
5841 || t->kind == ck_identity)
5847 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5848 a pointer to LOSER and re-running joust to produce the warning if WINNER
5849 is actually used. */
5852 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5854 candidate_warning *cw;
5856 cw = conversion_obstack_alloc (sizeof (candidate_warning));
5858 cw->next = winner->warnings;
5859 winner->warnings = cw;
5862 /* Compare two candidates for overloading as described in
5863 [over.match.best]. Return values:
5865 1: cand1 is better than cand2
5866 -1: cand2 is better than cand1
5867 0: cand1 and cand2 are indistinguishable */
5870 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5873 int off1 = 0, off2 = 0;
5877 /* Candidates that involve bad conversions are always worse than those
5879 if (cand1->viable > cand2->viable)
5881 if (cand1->viable < cand2->viable)
5884 /* If we have two pseudo-candidates for conversions to the same type,
5885 or two candidates for the same function, arbitrarily pick one. */
5886 if (cand1->fn == cand2->fn
5887 && (TYPE_P (cand1->fn) || DECL_P (cand1->fn)))
5890 /* a viable function F1
5891 is defined to be a better function than another viable function F2 if
5892 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5893 ICSi(F2), and then */
5895 /* for some argument j, ICSj(F1) is a better conversion sequence than
5898 /* For comparing static and non-static member functions, we ignore
5899 the implicit object parameter of the non-static function. The
5900 standard says to pretend that the static function has an object
5901 parm, but that won't work with operator overloading. */
5902 len = cand1->num_convs;
5903 if (len != cand2->num_convs)
5905 if (DECL_STATIC_FUNCTION_P (cand1->fn)
5906 && ! DECL_STATIC_FUNCTION_P (cand2->fn))
5908 else if (! DECL_STATIC_FUNCTION_P (cand1->fn)
5909 && DECL_STATIC_FUNCTION_P (cand2->fn))
5918 for (i = 0; i < len; ++i)
5920 conversion *t1 = cand1->convs[i + off1];
5921 conversion *t2 = cand2->convs[i + off2];
5922 int comp = compare_ics (t1, t2);
5927 && (CONVERSION_RANK (t1) + CONVERSION_RANK (t2)
5928 == cr_std + cr_promotion)
5929 && t1->kind == ck_std
5930 && t2->kind == ck_std
5931 && TREE_CODE (t1->type) == INTEGER_TYPE
5932 && TREE_CODE (t2->type) == INTEGER_TYPE
5933 && (TYPE_PRECISION (t1->type)
5934 == TYPE_PRECISION (t2->type))
5935 && (TYPE_UNSIGNED (t1->u.next->type)
5936 || (TREE_CODE (t1->u.next->type)
5939 tree type = t1->u.next->type;
5941 struct z_candidate *w, *l;
5943 type1 = t1->type, type2 = t2->type,
5944 w = cand1, l = cand2;
5946 type1 = t2->type, type2 = t1->type,
5947 w = cand2, l = cand1;
5951 warning ("passing `%T' chooses `%T' over `%T'",
5952 type, type1, type2);
5953 warning (" in call to `%D'", w->fn);
5959 if (winner && comp != winner)
5968 /* warn about confusing overload resolution for user-defined conversions,
5969 either between a constructor and a conversion op, or between two
5971 if (winner && warn_conversion && cand1->second_conv
5972 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
5973 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
5975 struct z_candidate *w, *l;
5976 bool give_warning = false;
5979 w = cand1, l = cand2;
5981 w = cand2, l = cand1;
5983 /* We don't want to complain about `X::operator T1 ()'
5984 beating `X::operator T2 () const', when T2 is a no less
5985 cv-qualified version of T1. */
5986 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
5987 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
5989 tree t = TREE_TYPE (TREE_TYPE (l->fn));
5990 tree f = TREE_TYPE (TREE_TYPE (w->fn));
5992 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
5997 if (!comp_ptr_ttypes (t, f))
5998 give_warning = true;
6001 give_warning = true;
6007 tree source = source_type (w->convs[0]);
6008 if (! DECL_CONSTRUCTOR_P (w->fn))
6009 source = TREE_TYPE (source);
6010 warning ("choosing `%D' over `%D'", w->fn, l->fn);
6011 warning (" for conversion from `%T' to `%T'",
6012 source, w->second_conv->type);
6013 warning (" because conversion sequence for the argument is better");
6023 F1 is a non-template function and F2 is a template function
6026 if (! cand1->template && cand2->template)
6028 else if (cand1->template && ! cand2->template)
6032 F1 and F2 are template functions and the function template for F1 is
6033 more specialized than the template for F2 according to the partial
6036 if (cand1->template && cand2->template)
6038 winner = more_specialized
6039 (TI_TEMPLATE (cand1->template), TI_TEMPLATE (cand2->template),
6041 /* Tell the deduction code how many real function arguments
6042 we saw, not counting the implicit 'this' argument. But,
6043 add_function_candidate() suppresses the "this" argument
6046 [temp.func.order]: The presence of unused ellipsis and default
6047 arguments has no effect on the partial ordering of function
6050 - (DECL_NONSTATIC_MEMBER_FUNCTION_P (cand1->fn)
6051 - DECL_CONSTRUCTOR_P (cand1->fn)));
6057 the context is an initialization by user-defined conversion (see
6058 _dcl.init_ and _over.match.user_) and the standard conversion
6059 sequence from the return type of F1 to the destination type (i.e.,
6060 the type of the entity being initialized) is a better conversion
6061 sequence than the standard conversion sequence from the return type
6062 of F2 to the destination type. */
6064 if (cand1->second_conv)
6066 winner = compare_ics (cand1->second_conv, cand2->second_conv);
6071 /* Check whether we can discard a builtin candidate, either because we
6072 have two identical ones or matching builtin and non-builtin candidates.
6074 (Pedantically in the latter case the builtin which matched the user
6075 function should not be added to the overload set, but we spot it here.
6078 ... the builtin candidates include ...
6079 - do not have the same parameter type list as any non-template
6080 non-member candidate. */
6082 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
6083 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
6085 for (i = 0; i < len; ++i)
6086 if (!same_type_p (cand1->convs[i]->type,
6087 cand2->convs[i]->type))
6089 if (i == cand1->num_convs)
6091 if (cand1->fn == cand2->fn)
6092 /* Two built-in candidates; arbitrarily pick one. */
6094 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
6095 /* cand1 is built-in; prefer cand2. */
6098 /* cand2 is built-in; prefer cand1. */
6103 /* If the two functions are the same (this can happen with declarations
6104 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
6105 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
6106 && equal_functions (cand1->fn, cand2->fn))
6111 /* Extension: If the worst conversion for one candidate is worse than the
6112 worst conversion for the other, take the first. */
6115 conversion_rank rank1 = cr_identity, rank2 = cr_identity;
6116 struct z_candidate *w = 0, *l = 0;
6118 for (i = 0; i < len; ++i)
6120 if (CONVERSION_RANK (cand1->convs[i+off1]) > rank1)
6121 rank1 = CONVERSION_RANK (cand1->convs[i+off1]);
6122 if (CONVERSION_RANK (cand2->convs[i + off2]) > rank2)
6123 rank2 = CONVERSION_RANK (cand2->convs[i + off2]);
6126 winner = 1, w = cand1, l = cand2;
6128 winner = -1, w = cand2, l = cand1;
6134 ISO C++ says that these are ambiguous, even \
6135 though the worst conversion for the first is better than \
6136 the worst conversion for the second:");
6137 print_z_candidate (_("candidate 1:"), w);
6138 print_z_candidate (_("candidate 2:"), l);
6146 my_friendly_assert (!winner, 20010121);
6150 /* Given a list of candidates for overloading, find the best one, if any.
6151 This algorithm has a worst case of O(2n) (winner is last), and a best
6152 case of O(n/2) (totally ambiguous); much better than a sorting
6155 static struct z_candidate *
6156 tourney (struct z_candidate *candidates)
6158 struct z_candidate *champ = candidates, *challenger;
6160 int champ_compared_to_predecessor = 0;
6162 /* Walk through the list once, comparing each current champ to the next
6163 candidate, knocking out a candidate or two with each comparison. */
6165 for (challenger = champ->next; challenger; )
6167 fate = joust (champ, challenger, 0);
6169 challenger = challenger->next;
6174 champ = challenger->next;
6177 champ_compared_to_predecessor = 0;
6182 champ_compared_to_predecessor = 1;
6185 challenger = champ->next;
6189 /* Make sure the champ is better than all the candidates it hasn't yet
6190 been compared to. */
6192 for (challenger = candidates;
6194 && !(champ_compared_to_predecessor && challenger->next == champ);
6195 challenger = challenger->next)
6197 fate = joust (champ, challenger, 0);
6205 /* Returns nonzero if things of type FROM can be converted to TO. */
6208 can_convert (tree to, tree from)
6210 return can_convert_arg (to, from, NULL_TREE);
6213 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
6216 can_convert_arg (tree to, tree from, tree arg)
6222 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6223 p = conversion_obstack_alloc (0);
6225 t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
6226 ok_p = (t && !t->bad_p);
6228 /* Free all the conversions we allocated. */
6229 obstack_free (&conversion_obstack, p);
6234 /* Like can_convert_arg, but allows dubious conversions as well. */
6237 can_convert_arg_bad (tree to, tree from, tree arg)
6242 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6243 p = conversion_obstack_alloc (0);
6244 /* Try to perform the conversion. */
6245 t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
6246 /* Free all the conversions we allocated. */
6247 obstack_free (&conversion_obstack, p);
6252 /* Convert EXPR to TYPE. Return the converted expression.
6254 Note that we allow bad conversions here because by the time we get to
6255 this point we are committed to doing the conversion. If we end up
6256 doing a bad conversion, convert_like will complain. */
6259 perform_implicit_conversion (tree type, tree expr)
6264 if (error_operand_p (expr))
6265 return error_mark_node;
6267 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6268 p = conversion_obstack_alloc (0);
6270 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6274 error ("could not convert `%E' to `%T'", expr, type);
6275 expr = error_mark_node;
6278 expr = convert_like (conv, expr);
6280 /* Free all the conversions we allocated. */
6281 obstack_free (&conversion_obstack, p);
6286 /* Convert EXPR to TYPE (as a direct-initialization) if that is
6287 permitted. If the conversion is valid, the converted expression is
6288 returned. Otherwise, NULL_TREE is returned, except in the case
6289 that TYPE is a class type; in that case, an error is issued. */
6292 perform_direct_initialization_if_possible (tree type, tree expr)
6297 if (type == error_mark_node || error_operand_p (expr))
6298 return error_mark_node;
6301 If the destination type is a (possibly cv-qualified) class type:
6303 -- If the initialization is direct-initialization ...,
6304 constructors are considered. ... If no constructor applies, or
6305 the overload resolution is ambiguous, the initialization is
6307 if (CLASS_TYPE_P (type))
6309 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
6310 build_tree_list (NULL_TREE, expr),
6311 type, LOOKUP_NORMAL);
6312 return build_cplus_new (type, expr);
6315 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6316 p = conversion_obstack_alloc (0);
6318 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
6320 if (!conv || conv->bad_p)
6323 expr = convert_like_real (conv, expr, NULL_TREE, 0, 0,
6324 /*issue_conversion_warnings=*/false);
6326 /* Free all the conversions we allocated. */
6327 obstack_free (&conversion_obstack, p);
6332 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
6333 is being bound to a temporary. Create and return a new VAR_DECL
6334 with the indicated TYPE; this variable will store the value to
6335 which the reference is bound. */
6338 make_temporary_var_for_ref_to_temp (tree decl, tree type)
6342 /* Create the variable. */
6343 var = build_decl (VAR_DECL, NULL_TREE, type);
6344 DECL_ARTIFICIAL (var) = 1;
6345 TREE_USED (var) = 1;
6347 /* Register the variable. */
6348 if (TREE_STATIC (decl))
6350 /* Namespace-scope or local static; give it a mangled name. */
6353 TREE_STATIC (var) = 1;
6354 name = mangle_ref_init_variable (decl);
6355 DECL_NAME (var) = name;
6356 SET_DECL_ASSEMBLER_NAME (var, name);
6357 var = pushdecl_top_level (var);
6361 /* Create a new cleanup level if necessary. */
6362 maybe_push_cleanup_level (type);
6363 /* Don't push unnamed temps. Do set DECL_CONTEXT, though. */
6364 DECL_CONTEXT (var) = current_function_decl;
6370 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6371 initializing a variable of that TYPE. If DECL is non-NULL, it is
6372 the VAR_DECL being initialized with the EXPR. (In that case, the
6373 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6374 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6375 return, if *CLEANUP is no longer NULL, it will be an expression
6376 that should be pushed as a cleanup after the returned expression
6377 is used to initialize DECL.
6379 Return the converted expression. */
6382 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6387 if (type == error_mark_node || error_operand_p (expr))
6388 return error_mark_node;
6390 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6391 p = conversion_obstack_alloc (0);
6393 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6394 if (!conv || conv->bad_p)
6396 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6397 && !real_lvalue_p (expr))
6398 error ("invalid initialization of non-const reference of "
6399 "type '%T' from a temporary of type '%T'",
6400 type, TREE_TYPE (expr));
6402 error ("invalid initialization of reference of type "
6403 "'%T' from expression of type '%T'", type,
6405 return error_mark_node;
6408 /* If DECL is non-NULL, then this special rule applies:
6412 The temporary to which the reference is bound or the temporary
6413 that is the complete object to which the reference is bound
6414 persists for the lifetime of the reference.
6416 The temporaries created during the evaluation of the expression
6417 initializing the reference, except the temporary to which the
6418 reference is bound, are destroyed at the end of the
6419 full-expression in which they are created.
6421 In that case, we store the converted expression into a new
6422 VAR_DECL in a new scope.
6424 However, we want to be careful not to create temporaries when
6425 they are not required. For example, given:
6428 struct D : public B {};
6432 there is no need to copy the return value from "f"; we can just
6433 extend its lifetime. Similarly, given:
6436 struct T { operator S(); };
6440 we can extend the lifetime of the return value of the conversion
6442 my_friendly_assert (conv->kind == ck_ref_bind, 20030302);
6446 tree base_conv_type;
6448 /* Skip over the REF_BIND. */
6449 conv = conv->u.next;
6450 /* If the next conversion is a BASE_CONV, skip that too -- but
6451 remember that the conversion was required. */
6452 if (conv->kind == ck_base && conv->need_temporary_p)
6454 if (conv->check_copy_constructor_p)
6455 check_constructor_callable (TREE_TYPE (expr), expr);
6456 base_conv_type = conv->type;
6457 conv = conv->u.next;
6460 base_conv_type = NULL_TREE;
6461 /* Perform the remainder of the conversion. */
6462 expr = convert_like_real (conv, expr,
6463 /*fn=*/NULL_TREE, /*argnum=*/0,
6465 /*issue_conversion_warnings=*/true);
6466 if (!real_lvalue_p (expr))
6471 /* Create the temporary variable. */
6472 type = TREE_TYPE (expr);
6473 var = make_temporary_var_for_ref_to_temp (decl, type);
6474 layout_decl (var, 0);
6475 /* If the rvalue is the result of a function call it will be
6476 a TARGET_EXPR. If it is some other construct (such as a
6477 member access expression where the underlying object is
6478 itself the result of a function call), turn it into a
6479 TARGET_EXPR here. It is important that EXPR be a
6480 TARGET_EXPR below since otherwise the INIT_EXPR will
6481 attempt to make a bitwise copy of EXPR to initialize
6483 if (TREE_CODE (expr) != TARGET_EXPR)
6484 expr = get_target_expr (expr);
6485 /* Create the INIT_EXPR that will initialize the temporary
6487 init = build (INIT_EXPR, type, var, expr);
6488 if (at_function_scope_p ())
6490 add_decl_expr (var);
6491 *cleanup = cxx_maybe_build_cleanup (var);
6493 /* We must be careful to destroy the temporary only
6494 after its initialization has taken place. If the
6495 initialization throws an exception, then the
6496 destructor should not be run. We cannot simply
6497 transform INIT into something like:
6499 (INIT, ({ CLEANUP_STMT; }))
6501 because emit_local_var always treats the
6502 initializer as a full-expression. Thus, the
6503 destructor would run too early; it would run at the
6504 end of initializing the reference variable, rather
6505 than at the end of the block enclosing the
6508 The solution is to pass back a cleanup expression
6509 which the caller is responsible for attaching to
6510 the statement tree. */
6514 rest_of_decl_compilation (var, NULL, /*toplev=*/1, at_eof);
6515 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6516 static_aggregates = tree_cons (NULL_TREE, var,
6519 /* Use its address to initialize the reference variable. */
6520 expr = build_address (var);
6521 expr = build (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6524 /* Take the address of EXPR. */
6525 expr = build_unary_op (ADDR_EXPR, expr, 0);
6526 /* If a BASE_CONV was required, perform it now. */
6528 expr = (perform_implicit_conversion
6529 (build_pointer_type (base_conv_type), expr));
6530 expr = build_nop (type, expr);
6533 /* Perform the conversion. */
6534 expr = convert_like (conv, expr);
6536 /* Free all the conversions we allocated. */
6537 obstack_free (&conversion_obstack, p);
6542 #include "gt-cp-call.h"