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 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 static tree build_field_call (tree, tree, tree);
44 static struct z_candidate * tourney (struct z_candidate *);
45 static int equal_functions (tree, tree);
46 static int joust (struct z_candidate *, struct z_candidate *, bool);
47 static int compare_ics (tree, tree);
48 static tree build_over_call (struct z_candidate *, int);
49 static tree build_java_interface_fn_ref (tree, tree);
50 #define convert_like(CONV, EXPR) \
51 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
52 /*issue_conversion_warnings=*/true)
53 #define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
54 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
55 /*issue_conversion_warnings=*/true)
56 static tree convert_like_real (tree, tree, tree, int, int, bool);
57 static void op_error (enum tree_code, enum tree_code, tree, tree,
59 static tree build_object_call (tree, tree);
60 static tree resolve_args (tree);
61 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
62 static void print_z_candidate (const char *, struct z_candidate *);
63 static void print_z_candidates (struct z_candidate *);
64 static tree build_this (tree);
65 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
66 static bool any_strictly_viable (struct z_candidate *);
67 static struct z_candidate *add_template_candidate
68 (struct z_candidate **, tree, tree, tree, tree, tree,
69 tree, tree, int, unification_kind_t);
70 static struct z_candidate *add_template_candidate_real
71 (struct z_candidate **, tree, tree, tree, tree, tree,
72 tree, tree, int, tree, unification_kind_t);
73 static struct z_candidate *add_template_conv_candidate
74 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
75 static void add_builtin_candidates
76 (struct z_candidate **, enum tree_code, enum tree_code,
78 static void add_builtin_candidate
79 (struct z_candidate **, enum tree_code, enum tree_code,
80 tree, tree, tree, tree *, tree *, int);
81 static bool is_complete (tree);
82 static void build_builtin_candidate
83 (struct z_candidate **, tree, tree, tree, tree *, tree *,
85 static struct z_candidate *add_conv_candidate
86 (struct z_candidate **, tree, tree, tree, tree, tree);
87 static struct z_candidate *add_function_candidate
88 (struct z_candidate **, tree, tree, tree, tree, tree, int);
89 static tree implicit_conversion (tree, tree, tree, int);
90 static tree standard_conversion (tree, tree, tree);
91 static tree reference_binding (tree, tree, tree, int);
92 static tree build_conv (enum tree_code, tree, tree);
93 static bool is_subseq (tree, tree);
94 static tree maybe_handle_ref_bind (tree *);
95 static void maybe_handle_implicit_object (tree *);
96 static struct z_candidate *add_candidate
97 (struct z_candidate **, tree, tree, tree, tree, tree, int);
98 static tree source_type (tree);
99 static void add_warning (struct z_candidate *, struct z_candidate *);
100 static bool reference_related_p (tree, tree);
101 static bool reference_compatible_p (tree, tree);
102 static tree convert_class_to_reference (tree, tree, tree);
103 static tree direct_reference_binding (tree, tree);
104 static bool promoted_arithmetic_type_p (tree);
105 static tree conditional_conversion (tree, tree);
106 static char *name_as_c_string (tree, tree, bool *);
107 static tree call_builtin_trap (void);
108 static tree prep_operand (tree);
109 static void add_candidates (tree, tree, tree, bool, tree, tree,
110 int, struct z_candidate **);
111 static tree merge_conversion_sequences (tree, tree);
114 build_vfield_ref (tree datum, tree type)
116 if (datum == error_mark_node)
117 return error_mark_node;
119 if (TREE_CODE (TREE_TYPE (datum)) == REFERENCE_TYPE)
120 datum = convert_from_reference (datum);
122 if (TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
123 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
124 datum = convert_to_base (datum, type, /*check_access=*/false);
126 return build (COMPONENT_REF, TREE_TYPE (TYPE_VFIELD (type)),
127 datum, TYPE_VFIELD (type));
130 /* Build a call to a member of an object. I.e., one that overloads
131 operator ()(), or is a pointer-to-function or pointer-to-method. */
134 build_field_call (tree instance_ptr, tree decl, tree parms)
138 if (decl == error_mark_node || decl == NULL_TREE)
141 if (TREE_CODE (decl) == FIELD_DECL || TREE_CODE (decl) == VAR_DECL)
143 /* If it's a field, try overloading operator (),
144 or calling if the field is a pointer-to-function. */
145 instance = build_indirect_ref (instance_ptr, NULL);
146 instance = build_class_member_access_expr (instance, decl,
147 /*access_path=*/NULL_TREE,
148 /*preserve_reference=*/false);
150 if (instance == error_mark_node)
151 return error_mark_node;
153 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
154 return build_new_op (CALL_EXPR, LOOKUP_NORMAL,
155 instance, parms, NULL_TREE);
156 else if (TREE_CODE (TREE_TYPE (instance)) == FUNCTION_TYPE
157 || (TREE_CODE (TREE_TYPE (instance)) == POINTER_TYPE
158 && (TREE_CODE (TREE_TYPE (TREE_TYPE (instance)))
160 return build_function_call (instance, parms);
166 /* Returns nonzero iff the destructor name specified in NAME
167 (a BIT_NOT_EXPR) matches BASETYPE. The operand of NAME can take many
171 check_dtor_name (tree basetype, tree name)
173 name = TREE_OPERAND (name, 0);
175 /* Just accept something we've already complained about. */
176 if (name == error_mark_node)
179 if (TREE_CODE (name) == TYPE_DECL)
180 name = TREE_TYPE (name);
181 else if (TYPE_P (name))
183 else if (TREE_CODE (name) == IDENTIFIER_NODE)
185 if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
186 || (TREE_CODE (basetype) == ENUMERAL_TYPE
187 && name == TYPE_IDENTIFIER (basetype)))
190 name = get_type_value (name);
194 template <class T> struct S { ~S(); };
198 NAME will be a class template. */
199 else if (DECL_CLASS_TEMPLATE_P (name))
204 if (name && TYPE_MAIN_VARIANT (basetype) == TYPE_MAIN_VARIANT (name))
209 /* We want the address of a function or method. We avoid creating a
210 pointer-to-member function. */
213 build_addr_func (tree function)
215 tree type = TREE_TYPE (function);
217 /* We have to do these by hand to avoid real pointer to member
219 if (TREE_CODE (type) == METHOD_TYPE)
221 if (TREE_CODE (function) == OFFSET_REF)
223 tree object = build_address (TREE_OPERAND (function, 0));
224 return get_member_function_from_ptrfunc (&object,
225 TREE_OPERAND (function, 1));
227 function = build_address (function);
230 function = decay_conversion (function);
235 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
236 POINTER_TYPE to those. Note, pointer to member function types
237 (TYPE_PTRMEMFUNC_P) must be handled by our callers. */
240 build_call (tree function, tree parms)
242 int is_constructor = 0;
249 function = build_addr_func (function);
251 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
253 sorry ("unable to call pointer to member function here");
254 return error_mark_node;
257 fntype = TREE_TYPE (TREE_TYPE (function));
258 result_type = TREE_TYPE (fntype);
260 if (TREE_CODE (function) == ADDR_EXPR
261 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
262 decl = TREE_OPERAND (function, 0);
266 /* We check both the decl and the type; a function may be known not to
267 throw without being declared throw(). */
268 nothrow = ((decl && TREE_NOTHROW (decl))
269 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
271 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
272 current_function_returns_abnormally = 1;
274 if (decl && TREE_DEPRECATED (decl))
275 warn_deprecated_use (decl);
276 require_complete_eh_spec_types (fntype, decl);
278 if (decl && DECL_CONSTRUCTOR_P (decl))
281 if (decl && ! TREE_USED (decl))
283 /* We invoke build_call directly for several library functions.
284 These may have been declared normally if we're building libgcc,
285 so we can't just check DECL_ARTIFICIAL. */
286 if (DECL_ARTIFICIAL (decl)
287 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), "__", 2))
293 /* Don't pass empty class objects by value. This is useful
294 for tags in STL, which are used to control overload resolution.
295 We don't need to handle other cases of copying empty classes. */
296 if (! decl || ! DECL_BUILT_IN (decl))
297 for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
298 if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
299 && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
301 tree t = build (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
302 TREE_VALUE (tmp) = build (COMPOUND_EXPR, TREE_TYPE (t),
303 TREE_VALUE (tmp), t);
306 function = build (CALL_EXPR, result_type, function, parms);
307 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
308 TREE_NOTHROW (function) = nothrow;
313 /* Build something of the form ptr->method (args)
314 or object.method (args). This can also build
315 calls to constructors, and find friends.
317 Member functions always take their class variable
320 INSTANCE is a class instance.
322 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
324 PARMS help to figure out what that NAME really refers to.
326 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
327 down to the real instance type to use for access checking. We need this
328 information to get protected accesses correct.
330 FLAGS is the logical disjunction of zero or more LOOKUP_
331 flags. See cp-tree.h for more info.
333 If this is all OK, calls build_function_call with the resolved
336 This function must also handle being called to perform
337 initialization, promotion/coercion of arguments, and
338 instantiation of default parameters.
340 Note that NAME may refer to an instance variable name. If
341 `operator()()' is defined for the type of that field, then we return
344 #ifdef GATHER_STATISTICS
345 extern int n_build_method_call;
349 build_method_call (tree instance, tree name, tree parms,
350 tree basetype_path, int flags)
354 tree template_args = NULL_TREE;
355 bool has_template_args = false;
357 #ifdef GATHER_STATISTICS
358 n_build_method_call++;
361 if (error_operand_p (instance)
362 || name == error_mark_node
363 || parms == error_mark_node)
364 return error_mark_node;
366 my_friendly_assert (!processing_template_decl, 20030707);
368 if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
369 instance = convert_from_reference (instance);
370 object_type = TREE_TYPE (instance);
372 if (TREE_CODE (name) == BIT_NOT_EXPR)
377 error ("destructors take no parameters");
379 if (! check_dtor_name (object_type, name))
381 ("destructor name `~%T' does not match type `%T' of expression",
382 TREE_OPERAND (name, 0), object_type);
384 if (! TYPE_HAS_DESTRUCTOR (complete_type (object_type)))
385 return convert_to_void (instance, /*implicit=*/NULL);
386 instance = default_conversion (instance);
387 instance_ptr = build_unary_op (ADDR_EXPR, instance, 0);
388 return build_delete (build_pointer_type (object_type),
389 instance_ptr, sfk_complete_destructor,
390 LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 0);
393 if (!CLASS_TYPE_P (object_type))
395 if ((flags & LOOKUP_COMPLAIN)
396 && TREE_TYPE (instance) != error_mark_node)
397 error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
398 name, instance, object_type);
399 return error_mark_node;
402 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
404 template_args = TREE_OPERAND (name, 1);
405 has_template_args = true;
406 name = TREE_OPERAND (name, 0);
408 if (TREE_CODE (name) == OVERLOAD)
409 name = DECL_NAME (get_first_fn (name));
410 else if (DECL_P (name))
411 name = DECL_NAME (name);
412 if (has_template_args)
413 fn = lookup_fnfields (object_type, name, /*protect=*/2);
415 fn = lookup_member (object_type, name, /*protect=*/2, /*want_type=*/false);
417 if (fn && TREE_CODE (fn) == TREE_LIST)
419 error ("request for member `%D' is ambiguous", name);
420 print_candidates (fn);
421 return error_mark_node;
424 /* If the name could not be found, issue an error. */
426 return unqualified_name_lookup_error (name);
428 if (BASELINK_P (fn) && has_template_args)
429 BASELINK_FUNCTIONS (fn)
430 = build_nt (TEMPLATE_ID_EXPR,
431 BASELINK_FUNCTIONS (fn),
433 if (BASELINK_P (fn) && basetype_path)
434 BASELINK_ACCESS_BINFO (fn) = basetype_path;
436 return build_new_method_call (instance, fn, parms,
437 /*conversion_path=*/NULL_TREE, flags);
440 /* New overloading code. */
442 struct z_candidate GTY(()) {
443 /* The FUNCTION_DECL that will be called if this candidate is
444 selected by overload resolution. */
446 /* The arguments to use when calling this function. */
448 /* The implicit conversion sequences for each of the arguments to
451 /* If FN is a user-defined conversion, the standard conversion
452 sequence from the type returned by FN to the desired destination
456 /* If FN is a member function, the binfo indicating the path used to
457 qualify the name of FN at the call site. This path is used to
458 determine whether or not FN is accessible if it is selected by
459 overload resolution. The DECL_CONTEXT of FN will always be a
460 (possibly improper) base of this binfo. */
462 /* If FN is a non-static member function, the binfo indicating the
463 subobject to which the `this' pointer should be converted if FN
464 is selected by overload resolution. The type pointed to the by
465 the `this' pointer must correspond to the most derived class
466 indicated by the CONVERSION_PATH. */
467 tree conversion_path;
470 struct z_candidate *next;
473 #define IDENTITY_RANK 0
479 #define ELLIPSIS_RANK 6
482 #define ICS_RANK(NODE) \
483 (ICS_BAD_FLAG (NODE) ? BAD_RANK \
484 : ICS_ELLIPSIS_FLAG (NODE) ? ELLIPSIS_RANK \
485 : ICS_USER_FLAG (NODE) ? USER_RANK \
486 : ICS_STD_RANK (NODE))
488 #define ICS_STD_RANK(NODE) TREE_COMPLEXITY (NODE)
490 #define ICS_USER_FLAG(NODE) TREE_LANG_FLAG_0 (NODE)
491 #define ICS_ELLIPSIS_FLAG(NODE) TREE_LANG_FLAG_1 (NODE)
492 #define ICS_THIS_FLAG(NODE) TREE_LANG_FLAG_2 (NODE)
493 #define ICS_BAD_FLAG(NODE) TREE_LANG_FLAG_3 (NODE)
495 /* In a REF_BIND or a BASE_CONV, this indicates that a temporary
496 should be created to hold the result of the conversion. */
497 #define NEED_TEMPORARY_P(NODE) TREE_LANG_FLAG_4 (NODE)
499 #define USER_CONV_CAND(NODE) WRAPPER_ZC (TREE_OPERAND (NODE, 1))
500 #define USER_CONV_FN(NODE) (USER_CONV_CAND (NODE)->fn)
503 null_ptr_cst_p (tree t)
507 A null pointer constant is an integral constant expression
508 (_expr.const_) rvalue of integer type that evaluates to zero. */
510 || (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
516 /* Returns nonzero if PARMLIST consists of only default parms and/or
520 sufficient_parms_p (tree parmlist)
522 for (; parmlist && parmlist != void_list_node;
523 parmlist = TREE_CHAIN (parmlist))
524 if (!TREE_PURPOSE (parmlist))
530 build_conv (enum tree_code code, tree type, tree from)
533 int rank = ICS_STD_RANK (from);
535 /* We can't use buildl1 here because CODE could be USER_CONV, which
536 takes two arguments. In that case, the caller is responsible for
537 filling in the second argument. */
538 t = make_node (code);
539 TREE_TYPE (t) = type;
540 TREE_OPERAND (t, 0) = from;
553 if (rank < EXACT_RANK)
559 ICS_STD_RANK (t) = rank;
560 ICS_USER_FLAG (t) = (code == USER_CONV || ICS_USER_FLAG (from));
561 ICS_BAD_FLAG (t) = ICS_BAD_FLAG (from);
566 strip_top_quals (tree t)
568 if (TREE_CODE (t) == ARRAY_TYPE)
570 return cp_build_qualified_type (t, 0);
573 /* Returns the standard conversion path (see [conv]) from type FROM to type
574 TO, if any. For proper handling of null pointer constants, you must
575 also pass the expression EXPR to convert from. */
578 standard_conversion (tree to, tree from, tree expr)
580 enum tree_code fcode, tcode;
582 bool fromref = false;
584 to = non_reference (to);
585 if (TREE_CODE (from) == REFERENCE_TYPE)
588 from = TREE_TYPE (from);
590 to = strip_top_quals (to);
591 from = strip_top_quals (from);
593 if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
594 && expr && type_unknown_p (expr))
596 expr = instantiate_type (to, expr, tf_none);
597 if (expr == error_mark_node)
599 from = TREE_TYPE (expr);
602 fcode = TREE_CODE (from);
603 tcode = TREE_CODE (to);
605 conv = build1 (IDENTITY_CONV, from, expr);
607 if (fcode == FUNCTION_TYPE)
609 from = build_pointer_type (from);
610 fcode = TREE_CODE (from);
611 conv = build_conv (LVALUE_CONV, from, conv);
613 else if (fcode == ARRAY_TYPE)
615 from = build_pointer_type (TREE_TYPE (from));
616 fcode = TREE_CODE (from);
617 conv = build_conv (LVALUE_CONV, from, conv);
619 else if (fromref || (expr && lvalue_p (expr)))
620 conv = build_conv (RVALUE_CONV, from, conv);
622 /* Allow conversion between `__complex__' data types */
623 if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
625 /* The standard conversion sequence to convert FROM to TO is
626 the standard conversion sequence to perform componentwise
628 tree part_conv = standard_conversion
629 (TREE_TYPE (to), TREE_TYPE (from), NULL_TREE);
633 conv = build_conv (TREE_CODE (part_conv), to, conv);
634 ICS_STD_RANK (conv) = ICS_STD_RANK (part_conv);
642 if (same_type_p (from, to))
645 if ((tcode == POINTER_TYPE || TYPE_PTR_TO_MEMBER_P (to))
646 && expr && null_ptr_cst_p (expr))
647 conv = build_conv (STD_CONV, to, conv);
648 else if (tcode == POINTER_TYPE && fcode == POINTER_TYPE
649 && TREE_CODE (TREE_TYPE (to)) == VECTOR_TYPE
650 && TREE_CODE (TREE_TYPE (from)) == VECTOR_TYPE
651 && ((*targetm.vector_opaque_p) (TREE_TYPE (to))
652 || (*targetm.vector_opaque_p) (TREE_TYPE (from))))
653 conv = build_conv (STD_CONV, to, conv);
654 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
655 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
657 /* For backwards brain damage compatibility, allow interconversion of
658 pointers and integers with a pedwarn. */
659 conv = build_conv (STD_CONV, to, conv);
660 ICS_BAD_FLAG (conv) = 1;
662 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE)
664 /* For backwards brain damage compatibility, allow interconversion of
665 enums and integers with a pedwarn. */
666 conv = build_conv (STD_CONV, to, conv);
667 ICS_BAD_FLAG (conv) = 1;
669 else if ((tcode == POINTER_TYPE && fcode == POINTER_TYPE)
670 || (TYPE_PTRMEM_P (to) && TYPE_PTRMEM_P (from)))
675 if (tcode == POINTER_TYPE
676 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
679 else if (VOID_TYPE_P (TREE_TYPE (to))
680 && !TYPE_PTRMEM_P (from)
681 && TREE_CODE (TREE_TYPE (from)) != FUNCTION_TYPE)
683 from = build_pointer_type
684 (cp_build_qualified_type (void_type_node,
685 cp_type_quals (TREE_TYPE (from))));
686 conv = build_conv (PTR_CONV, from, conv);
688 else if (TYPE_PTRMEM_P (from))
690 tree fbase = TYPE_PTRMEM_CLASS_TYPE (from);
691 tree tbase = TYPE_PTRMEM_CLASS_TYPE (to);
693 if (DERIVED_FROM_P (fbase, tbase)
694 && (same_type_ignoring_top_level_qualifiers_p
695 (TYPE_PTRMEM_POINTED_TO_TYPE (from),
696 TYPE_PTRMEM_POINTED_TO_TYPE (to))))
698 from = build_ptrmem_type (tbase,
699 TYPE_PTRMEM_POINTED_TO_TYPE (from));
700 conv = build_conv (PMEM_CONV, from, conv);
703 else if (IS_AGGR_TYPE (TREE_TYPE (from))
704 && IS_AGGR_TYPE (TREE_TYPE (to)))
706 if (DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
709 cp_build_qualified_type (TREE_TYPE (to),
710 cp_type_quals (TREE_TYPE (from)));
711 from = build_pointer_type (from);
712 conv = build_conv (PTR_CONV, from, conv);
716 if (tcode == POINTER_TYPE)
718 to_pointee = TREE_TYPE (to);
719 from_pointee = TREE_TYPE (from);
723 to_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (to);
724 from_pointee = TYPE_PTRMEM_POINTED_TO_TYPE (from);
727 if (same_type_p (from, to))
729 else if (comp_ptr_ttypes (to_pointee, from_pointee))
730 conv = build_conv (QUAL_CONV, to, conv);
731 else if (expr && string_conv_p (to, expr, 0))
732 /* converting from string constant to char *. */
733 conv = build_conv (QUAL_CONV, to, conv);
734 else if (ptr_reasonably_similar (to_pointee, from_pointee))
736 conv = build_conv (PTR_CONV, to, conv);
737 ICS_BAD_FLAG (conv) = 1;
744 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
746 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
747 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
748 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
749 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
751 if (!DERIVED_FROM_P (fbase, tbase)
752 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
753 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
754 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
755 || cp_type_quals (fbase) != cp_type_quals (tbase))
758 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
759 from = build_method_type_directly (from,
761 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
762 from = build_ptrmemfunc_type (build_pointer_type (from));
763 conv = build_conv (PMEM_CONV, from, conv);
765 else if (tcode == BOOLEAN_TYPE)
769 An rvalue of arithmetic, enumeration, pointer, or pointer to
770 member type can be converted to an rvalue of type bool. */
771 if (ARITHMETIC_TYPE_P (from)
772 || fcode == ENUMERAL_TYPE
773 || fcode == POINTER_TYPE
774 || TYPE_PTR_TO_MEMBER_P (from))
776 conv = build_conv (STD_CONV, to, conv);
777 if (fcode == POINTER_TYPE
778 || TYPE_PTRMEM_P (from)
779 || (TYPE_PTRMEMFUNC_P (from)
780 && ICS_STD_RANK (conv) < PBOOL_RANK))
781 ICS_STD_RANK (conv) = PBOOL_RANK;
787 /* We don't check for ENUMERAL_TYPE here because there are no standard
788 conversions to enum type. */
789 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
790 || tcode == REAL_TYPE)
792 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
794 conv = build_conv (STD_CONV, to, conv);
796 /* Give this a better rank if it's a promotion. */
797 if (same_type_p (to, type_promotes_to (from))
798 && ICS_STD_RANK (TREE_OPERAND (conv, 0)) <= PROMO_RANK)
799 ICS_STD_RANK (conv) = PROMO_RANK;
801 else if (fcode == VECTOR_TYPE && tcode == VECTOR_TYPE
802 && ((*targetm.vector_opaque_p) (from)
803 || (*targetm.vector_opaque_p) (to)))
804 return build_conv (STD_CONV, to, conv);
805 else if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
806 && is_properly_derived_from (from, to))
808 if (TREE_CODE (conv) == RVALUE_CONV)
809 conv = TREE_OPERAND (conv, 0);
810 conv = build_conv (BASE_CONV, to, conv);
811 /* The derived-to-base conversion indicates the initialization
812 of a parameter with base type from an object of a derived
813 type. A temporary object is created to hold the result of
815 NEED_TEMPORARY_P (conv) = 1;
823 /* Returns nonzero if T1 is reference-related to T2. */
826 reference_related_p (tree t1, tree t2)
828 t1 = TYPE_MAIN_VARIANT (t1);
829 t2 = TYPE_MAIN_VARIANT (t2);
833 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
834 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
836 return (same_type_p (t1, t2)
837 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
838 && DERIVED_FROM_P (t1, t2)));
841 /* Returns nonzero if T1 is reference-compatible with T2. */
844 reference_compatible_p (tree t1, tree t2)
848 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
849 reference-related to T2 and cv1 is the same cv-qualification as,
850 or greater cv-qualification than, cv2. */
851 return (reference_related_p (t1, t2)
852 && at_least_as_qualified_p (t1, t2));
855 /* Determine whether or not the EXPR (of class type S) can be
856 converted to T as in [over.match.ref]. */
859 convert_class_to_reference (tree t, tree s, tree expr)
865 struct z_candidate *candidates;
866 struct z_candidate *cand;
869 conversions = lookup_conversions (s);
875 Assuming that "cv1 T" is the underlying type of the reference
876 being initialized, and "cv S" is the type of the initializer
877 expression, with S a class type, the candidate functions are
880 --The conversion functions of S and its base classes are
881 considered. Those that are not hidden within S and yield type
882 "reference to cv2 T2", where "cv1 T" is reference-compatible
883 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
885 The argument list has one argument, which is the initializer
890 /* Conceptually, we should take the address of EXPR and put it in
891 the argument list. Unfortunately, however, that can result in
892 error messages, which we should not issue now because we are just
893 trying to find a conversion operator. Therefore, we use NULL,
894 cast to the appropriate type. */
895 arglist = build_int_2 (0, 0);
896 TREE_TYPE (arglist) = build_pointer_type (s);
897 arglist = build_tree_list (NULL_TREE, arglist);
899 reference_type = build_reference_type (t);
903 tree fns = TREE_VALUE (conversions);
905 for (; fns; fns = OVL_NEXT (fns))
907 tree f = OVL_CURRENT (fns);
908 tree t2 = TREE_TYPE (TREE_TYPE (f));
912 /* If this is a template function, try to get an exact
914 if (TREE_CODE (f) == TEMPLATE_DECL)
916 cand = add_template_candidate (&candidates,
922 TREE_PURPOSE (conversions),
928 /* Now, see if the conversion function really returns
929 an lvalue of the appropriate type. From the
930 point of view of unification, simply returning an
931 rvalue of the right type is good enough. */
933 t2 = TREE_TYPE (TREE_TYPE (f));
934 if (TREE_CODE (t2) != REFERENCE_TYPE
935 || !reference_compatible_p (t, TREE_TYPE (t2)))
937 candidates = candidates->next;
942 else if (TREE_CODE (t2) == REFERENCE_TYPE
943 && reference_compatible_p (t, TREE_TYPE (t2)))
944 cand = add_function_candidate (&candidates, f, s, arglist,
946 TREE_PURPOSE (conversions),
950 /* Build a standard conversion sequence indicating the
951 binding from the reference type returned by the
952 function to the desired REFERENCE_TYPE. */
954 = (direct_reference_binding
956 build1 (IDENTITY_CONV,
957 TREE_TYPE (TREE_TYPE (TREE_TYPE (cand->fn))),
960 conversions = TREE_CHAIN (conversions);
963 candidates = splice_viable (candidates, pedantic, &any_viable_p);
964 /* If none of the conversion functions worked out, let our caller
969 cand = tourney (candidates);
973 /* Now that we know that this is the function we're going to use fix
974 the dummy first argument. */
975 cand->args = tree_cons (NULL_TREE,
977 TREE_CHAIN (cand->args));
979 /* Build a user-defined conversion sequence representing the
981 conv = build_conv (USER_CONV,
982 TREE_TYPE (TREE_TYPE (cand->fn)),
983 build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
984 TREE_OPERAND (conv, 1) = build_zc_wrapper (cand);
986 /* Merge it with the standard conversion sequence from the
987 conversion function's return type to the desired type. */
988 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
990 if (cand->viable == -1)
991 ICS_BAD_FLAG (conv) = 1;
993 return cand->second_conv;
996 /* A reference of the indicated TYPE is being bound directly to the
997 expression represented by the implicit conversion sequence CONV.
998 Return a conversion sequence for this binding. */
1001 direct_reference_binding (tree type, tree conv)
1005 my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 20030306);
1006 my_friendly_assert (TREE_CODE (TREE_TYPE (conv)) != REFERENCE_TYPE,
1009 t = TREE_TYPE (type);
1013 When a parameter of reference type binds directly
1014 (_dcl.init.ref_) to an argument expression, the implicit
1015 conversion sequence is the identity conversion, unless the
1016 argument expression has a type that is a derived class of the
1017 parameter type, in which case the implicit conversion sequence is
1018 a derived-to-base Conversion.
1020 If the parameter binds directly to the result of applying a
1021 conversion function to the argument expression, the implicit
1022 conversion sequence is a user-defined conversion sequence
1023 (_over.ics.user_), with the second standard conversion sequence
1024 either an identity conversion or, if the conversion function
1025 returns an entity of a type that is a derived class of the
1026 parameter type, a derived-to-base conversion. */
1027 if (!same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (conv)))
1029 /* Represent the derived-to-base conversion. */
1030 conv = build_conv (BASE_CONV, t, conv);
1031 /* We will actually be binding to the base-class subobject in
1032 the derived class, so we mark this conversion appropriately.
1033 That way, convert_like knows not to generate a temporary. */
1034 NEED_TEMPORARY_P (conv) = 0;
1036 return build_conv (REF_BIND, type, conv);
1039 /* Returns the conversion path from type FROM to reference type TO for
1040 purposes of reference binding. For lvalue binding, either pass a
1041 reference type to FROM or an lvalue expression to EXPR. If the
1042 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1043 the conversion returned. */
1046 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1048 tree conv = NULL_TREE;
1049 tree to = TREE_TYPE (rto);
1053 cp_lvalue_kind lvalue_p = clk_none;
1055 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1057 expr = instantiate_type (to, expr, tf_none);
1058 if (expr == error_mark_node)
1060 from = TREE_TYPE (expr);
1063 if (TREE_CODE (from) == REFERENCE_TYPE)
1065 /* Anything with reference type is an lvalue. */
1066 lvalue_p = clk_ordinary;
1067 from = TREE_TYPE (from);
1070 lvalue_p = real_lvalue_p (expr);
1072 /* Figure out whether or not the types are reference-related and
1073 reference compatible. We have do do this after stripping
1074 references from FROM. */
1075 related_p = reference_related_p (to, from);
1076 compatible_p = reference_compatible_p (to, from);
1078 if (lvalue_p && compatible_p)
1082 If the initializer expression
1084 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1085 is reference-compatible with "cv2 T2,"
1087 the reference is bound directly to the initializer expression
1089 conv = build1 (IDENTITY_CONV, from, expr);
1090 conv = direct_reference_binding (rto, conv);
1091 if ((lvalue_p & clk_bitfield) != 0
1092 || ((lvalue_p & clk_packed) != 0 && !TYPE_PACKED (to)))
1093 /* For the purposes of overload resolution, we ignore the fact
1094 this expression is a bitfield or packed field. (In particular,
1095 [over.ics.ref] says specifically that a function with a
1096 non-const reference parameter is viable even if the
1097 argument is a bitfield.)
1099 However, when we actually call the function we must create
1100 a temporary to which to bind the reference. If the
1101 reference is volatile, or isn't const, then we cannot make
1102 a temporary, so we just issue an error when the conversion
1104 NEED_TEMPORARY_P (conv) = 1;
1108 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1112 If the initializer expression
1114 -- has a class type (i.e., T2 is a class type) can be
1115 implicitly converted to an lvalue of type "cv3 T3," where
1116 "cv1 T1" is reference-compatible with "cv3 T3". (this
1117 conversion is selected by enumerating the applicable
1118 conversion functions (_over.match.ref_) and choosing the
1119 best one through overload resolution. (_over.match_).
1121 the reference is bound to the lvalue result of the conversion
1122 in the second case. */
1123 conv = convert_class_to_reference (to, from, expr);
1128 /* From this point on, we conceptually need temporaries, even if we
1129 elide them. Only the cases above are "direct bindings". */
1130 if (flags & LOOKUP_NO_TEMP_BIND)
1135 When a parameter of reference type is not bound directly to an
1136 argument expression, the conversion sequence is the one required
1137 to convert the argument expression to the underlying type of the
1138 reference according to _over.best.ics_. Conceptually, this
1139 conversion sequence corresponds to copy-initializing a temporary
1140 of the underlying type with the argument expression. Any
1141 difference in top-level cv-qualification is subsumed by the
1142 initialization itself and does not constitute a conversion. */
1146 Otherwise, the reference shall be to a non-volatile const type. */
1147 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1152 If the initializer expression is an rvalue, with T2 a class type,
1153 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1154 is bound in one of the following ways:
1156 -- The reference is bound to the object represented by the rvalue
1157 or to a sub-object within that object.
1161 We use the first alternative. The implicit conversion sequence
1162 is supposed to be same as we would obtain by generating a
1163 temporary. Fortunately, if the types are reference compatible,
1164 then this is either an identity conversion or the derived-to-base
1165 conversion, just as for direct binding. */
1166 if (CLASS_TYPE_P (from) && compatible_p)
1168 conv = build1 (IDENTITY_CONV, from, expr);
1169 return direct_reference_binding (rto, conv);
1174 Otherwise, a temporary of type "cv1 T1" is created and
1175 initialized from the initializer expression using the rules for a
1176 non-reference copy initialization. If T1 is reference-related to
1177 T2, cv1 must be the same cv-qualification as, or greater
1178 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1179 if (related_p && !at_least_as_qualified_p (to, from))
1182 conv = implicit_conversion (to, from, expr, flags);
1186 conv = build_conv (REF_BIND, rto, conv);
1187 /* This reference binding, unlike those above, requires the
1188 creation of a temporary. */
1189 NEED_TEMPORARY_P (conv) = 1;
1194 /* Returns the implicit conversion sequence (see [over.ics]) from type FROM
1195 to type TO. The optional expression EXPR may affect the conversion.
1196 FLAGS are the usual overloading flags. Only LOOKUP_NO_CONVERSION is
1200 implicit_conversion (tree to, tree from, tree expr, int flags)
1204 if (from == error_mark_node || to == error_mark_node
1205 || expr == error_mark_node)
1208 if (TREE_CODE (to) == REFERENCE_TYPE)
1209 conv = reference_binding (to, from, expr, flags);
1211 conv = standard_conversion (to, from, expr);
1216 if (expr != NULL_TREE
1217 && (IS_AGGR_TYPE (from)
1218 || IS_AGGR_TYPE (to))
1219 && (flags & LOOKUP_NO_CONVERSION) == 0)
1221 struct z_candidate *cand;
1223 cand = build_user_type_conversion_1
1224 (to, expr, LOOKUP_ONLYCONVERTING);
1226 conv = cand->second_conv;
1228 /* We used to try to bind a reference to a temporary here, but that
1229 is now handled by the recursive call to this function at the end
1230 of reference_binding. */
1237 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1240 static struct z_candidate *
1241 add_candidate (struct z_candidate **candidates,
1242 tree fn, tree args, tree convs, tree access_path,
1243 tree conversion_path, int viable)
1245 struct z_candidate *cand = ggc_alloc_cleared (sizeof (struct z_candidate));
1249 cand->convs = convs;
1250 cand->access_path = access_path;
1251 cand->conversion_path = conversion_path;
1252 cand->viable = viable;
1253 cand->next = *candidates;
1259 /* Create an overload candidate for the function or method FN called with
1260 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1261 to implicit_conversion.
1263 CTYPE, if non-NULL, is the type we want to pretend this function
1264 comes from for purposes of overload resolution. */
1266 static struct z_candidate *
1267 add_function_candidate (struct z_candidate **candidates,
1268 tree fn, tree ctype, tree arglist,
1269 tree access_path, tree conversion_path,
1272 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1275 tree parmnode, argnode;
1279 /* Built-in functions that haven't been declared don't really
1281 if (DECL_ANTICIPATED (fn))
1284 /* The `this', `in_chrg' and VTT arguments to constructors are not
1285 considered in overload resolution. */
1286 if (DECL_CONSTRUCTOR_P (fn))
1288 parmlist = skip_artificial_parms_for (fn, parmlist);
1289 orig_arglist = arglist;
1290 arglist = skip_artificial_parms_for (fn, arglist);
1293 orig_arglist = arglist;
1295 len = list_length (arglist);
1296 convs = make_tree_vec (len);
1298 /* 13.3.2 - Viable functions [over.match.viable]
1299 First, to be a viable function, a candidate function shall have enough
1300 parameters to agree in number with the arguments in the list.
1302 We need to check this first; otherwise, checking the ICSes might cause
1303 us to produce an ill-formed template instantiation. */
1305 parmnode = parmlist;
1306 for (i = 0; i < len; ++i)
1308 if (parmnode == NULL_TREE || parmnode == void_list_node)
1310 parmnode = TREE_CHAIN (parmnode);
1313 if (i < len && parmnode)
1316 /* Make sure there are default args for the rest of the parms. */
1317 else if (!sufficient_parms_p (parmnode))
1323 /* Second, for F to be a viable function, there shall exist for each
1324 argument an implicit conversion sequence that converts that argument
1325 to the corresponding parameter of F. */
1327 parmnode = parmlist;
1330 for (i = 0; i < len; ++i)
1332 tree arg = TREE_VALUE (argnode);
1333 tree argtype = lvalue_type (arg);
1337 if (parmnode == void_list_node)
1340 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1341 && ! DECL_CONSTRUCTOR_P (fn));
1345 tree parmtype = TREE_VALUE (parmnode);
1347 /* The type of the implicit object parameter ('this') for
1348 overload resolution is not always the same as for the
1349 function itself; conversion functions are considered to
1350 be members of the class being converted, and functions
1351 introduced by a using-declaration are considered to be
1352 members of the class that uses them.
1354 Since build_over_call ignores the ICS for the `this'
1355 parameter, we can just change the parm type. */
1356 if (ctype && is_this)
1359 = build_qualified_type (ctype,
1360 TYPE_QUALS (TREE_TYPE (parmtype)));
1361 parmtype = build_pointer_type (parmtype);
1364 t = implicit_conversion (parmtype, argtype, arg, flags);
1368 t = build1 (IDENTITY_CONV, argtype, arg);
1369 ICS_ELLIPSIS_FLAG (t) = 1;
1373 ICS_THIS_FLAG (t) = 1;
1375 TREE_VEC_ELT (convs, i) = t;
1382 if (ICS_BAD_FLAG (t))
1386 parmnode = TREE_CHAIN (parmnode);
1387 argnode = TREE_CHAIN (argnode);
1391 return add_candidate (candidates, fn, orig_arglist, convs, access_path,
1392 conversion_path, viable);
1395 /* Create an overload candidate for the conversion function FN which will
1396 be invoked for expression OBJ, producing a pointer-to-function which
1397 will in turn be called with the argument list ARGLIST, and add it to
1398 CANDIDATES. FLAGS is passed on to implicit_conversion.
1400 Actually, we don't really care about FN; we care about the type it
1401 converts to. There may be multiple conversion functions that will
1402 convert to that type, and we rely on build_user_type_conversion_1 to
1403 choose the best one; so when we create our candidate, we record the type
1404 instead of the function. */
1406 static struct z_candidate *
1407 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1408 tree arglist, tree access_path, tree conversion_path)
1410 tree totype = TREE_TYPE (TREE_TYPE (fn));
1411 int i, len, viable, flags;
1412 tree parmlist, convs, parmnode, argnode;
1414 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1415 parmlist = TREE_TYPE (parmlist);
1416 parmlist = TYPE_ARG_TYPES (parmlist);
1418 len = list_length (arglist) + 1;
1419 convs = make_tree_vec (len);
1420 parmnode = parmlist;
1423 flags = LOOKUP_NORMAL;
1425 /* Don't bother looking up the same type twice. */
1426 if (*candidates && (*candidates)->fn == totype)
1429 for (i = 0; i < len; ++i)
1431 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1432 tree argtype = lvalue_type (arg);
1436 t = implicit_conversion (totype, argtype, arg, flags);
1437 else if (parmnode == void_list_node)
1440 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, flags);
1443 t = build1 (IDENTITY_CONV, argtype, arg);
1444 ICS_ELLIPSIS_FLAG (t) = 1;
1447 TREE_VEC_ELT (convs, i) = t;
1451 if (ICS_BAD_FLAG (t))
1458 parmnode = TREE_CHAIN (parmnode);
1459 argnode = TREE_CHAIN (argnode);
1465 if (!sufficient_parms_p (parmnode))
1468 return add_candidate (candidates, totype, arglist, convs, access_path,
1469 conversion_path, viable);
1473 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1474 tree type1, tree type2, tree *args, tree *argtypes,
1484 convs = make_tree_vec (args[2] ? 3 : (args[1] ? 2 : 1));
1486 for (i = 0; i < 2; ++i)
1491 t = implicit_conversion (types[i], argtypes[i], args[i], flags);
1495 /* We need something for printing the candidate. */
1496 t = build1 (IDENTITY_CONV, types[i], NULL_TREE);
1498 else if (ICS_BAD_FLAG (t))
1500 TREE_VEC_ELT (convs, i) = t;
1503 /* For COND_EXPR we rearranged the arguments; undo that now. */
1506 TREE_VEC_ELT (convs, 2) = TREE_VEC_ELT (convs, 1);
1507 TREE_VEC_ELT (convs, 1) = TREE_VEC_ELT (convs, 0);
1508 t = implicit_conversion (boolean_type_node, argtypes[2], args[2], flags);
1510 TREE_VEC_ELT (convs, 0) = t;
1515 add_candidate (candidates, fnname, /*args=*/NULL_TREE, convs,
1516 /*access_path=*/NULL_TREE,
1517 /*conversion_path=*/NULL_TREE,
1522 is_complete (tree t)
1524 return COMPLETE_TYPE_P (complete_type (t));
1527 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1530 promoted_arithmetic_type_p (tree type)
1534 In this section, the term promoted integral type is used to refer
1535 to those integral types which are preserved by integral promotion
1536 (including e.g. int and long but excluding e.g. char).
1537 Similarly, the term promoted arithmetic type refers to promoted
1538 integral types plus floating types. */
1539 return ((INTEGRAL_TYPE_P (type)
1540 && same_type_p (type_promotes_to (type), type))
1541 || TREE_CODE (type) == REAL_TYPE);
1544 /* Create any builtin operator overload candidates for the operator in
1545 question given the converted operand types TYPE1 and TYPE2. The other
1546 args are passed through from add_builtin_candidates to
1547 build_builtin_candidate.
1549 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1550 If CODE is requires candidates operands of the same type of the kind
1551 of which TYPE1 and TYPE2 are, we add both candidates
1552 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1555 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1556 enum tree_code code2, tree fnname, tree type1,
1557 tree type2, tree *args, tree *argtypes, int flags)
1561 case POSTINCREMENT_EXPR:
1562 case POSTDECREMENT_EXPR:
1563 args[1] = integer_zero_node;
1564 type2 = integer_type_node;
1573 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1574 and VQ is either volatile or empty, there exist candidate operator
1575 functions of the form
1576 VQ T& operator++(VQ T&);
1577 T operator++(VQ T&, int);
1578 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1579 type other than bool, and VQ is either volatile or empty, there exist
1580 candidate operator functions of the form
1581 VQ T& operator--(VQ T&);
1582 T operator--(VQ T&, int);
1583 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1584 complete object type, and VQ is either volatile or empty, there exist
1585 candidate operator functions of the form
1586 T*VQ& operator++(T*VQ&);
1587 T*VQ& operator--(T*VQ&);
1588 T* operator++(T*VQ&, int);
1589 T* operator--(T*VQ&, int); */
1591 case POSTDECREMENT_EXPR:
1592 case PREDECREMENT_EXPR:
1593 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1595 case POSTINCREMENT_EXPR:
1596 case PREINCREMENT_EXPR:
1597 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1599 type1 = build_reference_type (type1);
1604 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1605 exist candidate operator functions of the form
1609 8 For every function type T, there exist candidate operator functions of
1611 T& operator*(T*); */
1614 if (TREE_CODE (type1) == POINTER_TYPE
1615 && (TYPE_PTROB_P (type1)
1616 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1620 /* 9 For every type T, there exist candidate operator functions of the form
1623 10For every promoted arithmetic type T, there exist candidate operator
1624 functions of the form
1628 case CONVERT_EXPR: /* unary + */
1629 if (TREE_CODE (type1) == POINTER_TYPE)
1632 if (ARITHMETIC_TYPE_P (type1))
1636 /* 11For every promoted integral type T, there exist candidate operator
1637 functions of the form
1641 if (INTEGRAL_TYPE_P (type1))
1645 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1646 is the same type as C2 or is a derived class of C2, T is a complete
1647 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1648 there exist candidate operator functions of the form
1649 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1650 where CV12 is the union of CV1 and CV2. */
1653 if (TREE_CODE (type1) == POINTER_TYPE
1654 && TYPE_PTR_TO_MEMBER_P (type2))
1656 tree c1 = TREE_TYPE (type1);
1657 tree c2 = TYPE_PTRMEM_CLASS_TYPE (type2);
1659 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1660 && (TYPE_PTRMEMFUNC_P (type2)
1661 || is_complete (TREE_TYPE (TREE_TYPE (type2)))))
1666 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1667 didate operator functions of the form
1672 bool operator<(L, R);
1673 bool operator>(L, R);
1674 bool operator<=(L, R);
1675 bool operator>=(L, R);
1676 bool operator==(L, R);
1677 bool operator!=(L, R);
1678 where LR is the result of the usual arithmetic conversions between
1681 14For every pair of types T and I, where T is a cv-qualified or cv-
1682 unqualified complete object type and I is a promoted integral type,
1683 there exist candidate operator functions of the form
1684 T* operator+(T*, I);
1685 T& operator[](T*, I);
1686 T* operator-(T*, I);
1687 T* operator+(I, T*);
1688 T& operator[](I, T*);
1690 15For every T, where T is a pointer to complete object type, there exist
1691 candidate operator functions of the form112)
1692 ptrdiff_t operator-(T, T);
1694 16For every pointer or enumeration type T, there exist candidate operator
1695 functions of the form
1696 bool operator<(T, T);
1697 bool operator>(T, T);
1698 bool operator<=(T, T);
1699 bool operator>=(T, T);
1700 bool operator==(T, T);
1701 bool operator!=(T, T);
1703 17For every pointer to member type T, there exist candidate operator
1704 functions of the form
1705 bool operator==(T, T);
1706 bool operator!=(T, T); */
1709 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1711 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1713 type2 = ptrdiff_type_node;
1717 case TRUNC_DIV_EXPR:
1718 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1724 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1725 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1727 if (TYPE_PTR_TO_MEMBER_P (type1) && null_ptr_cst_p (args[1]))
1732 if (TYPE_PTR_TO_MEMBER_P (type2) && null_ptr_cst_p (args[0]))
1744 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1746 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1748 if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
1750 if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
1755 if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
1763 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1766 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1768 type1 = ptrdiff_type_node;
1771 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1773 type2 = ptrdiff_type_node;
1778 /* 18For every pair of promoted integral types L and R, there exist candi-
1779 date operator functions of the form
1786 where LR is the result of the usual arithmetic conversions between
1789 case TRUNC_MOD_EXPR:
1795 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1799 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1800 type, VQ is either volatile or empty, and R is a promoted arithmetic
1801 type, there exist candidate operator functions of the form
1802 VQ L& operator=(VQ L&, R);
1803 VQ L& operator*=(VQ L&, R);
1804 VQ L& operator/=(VQ L&, R);
1805 VQ L& operator+=(VQ L&, R);
1806 VQ L& operator-=(VQ L&, R);
1808 20For every pair T, VQ), where T is any type and VQ is either volatile
1809 or empty, there exist candidate operator functions of the form
1810 T*VQ& operator=(T*VQ&, T*);
1812 21For every pair T, VQ), where T is a pointer to member type and VQ is
1813 either volatile or empty, there exist candidate operator functions of
1815 VQ T& operator=(VQ T&, T);
1817 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1818 unqualified complete object type, VQ is either volatile or empty, and
1819 I is a promoted integral type, there exist candidate operator func-
1821 T*VQ& operator+=(T*VQ&, I);
1822 T*VQ& operator-=(T*VQ&, I);
1824 23For every triple L, VQ, R), where L is an integral or enumeration
1825 type, VQ is either volatile or empty, and R is a promoted integral
1826 type, there exist candidate operator functions of the form
1828 VQ L& operator%=(VQ L&, R);
1829 VQ L& operator<<=(VQ L&, R);
1830 VQ L& operator>>=(VQ L&, R);
1831 VQ L& operator&=(VQ L&, R);
1832 VQ L& operator^=(VQ L&, R);
1833 VQ L& operator|=(VQ L&, R); */
1840 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1842 type2 = ptrdiff_type_node;
1846 case TRUNC_DIV_EXPR:
1847 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1851 case TRUNC_MOD_EXPR:
1857 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1862 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1864 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1865 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1866 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1867 || ((TYPE_PTRMEMFUNC_P (type1)
1868 || TREE_CODE (type1) == POINTER_TYPE)
1869 && null_ptr_cst_p (args[1])))
1879 type1 = build_reference_type (type1);
1885 For every pair of promoted arithmetic types L and R, there
1886 exist candidate operator functions of the form
1888 LR operator?(bool, L, R);
1890 where LR is the result of the usual arithmetic conversions
1891 between types L and R.
1893 For every type T, where T is a pointer or pointer-to-member
1894 type, there exist candidate operator functions of the form T
1895 operator?(bool, T, T); */
1897 if (promoted_arithmetic_type_p (type1)
1898 && promoted_arithmetic_type_p (type2))
1902 /* Otherwise, the types should be pointers. */
1903 if (!(TYPE_PTR_P (type1) || TYPE_PTR_TO_MEMBER_P (type1))
1904 || !(TYPE_PTR_P (type2) || TYPE_PTR_TO_MEMBER_P (type2)))
1907 /* We don't check that the two types are the same; the logic
1908 below will actually create two candidates; one in which both
1909 parameter types are TYPE1, and one in which both parameter
1917 /* If we're dealing with two pointer types or two enumeral types,
1918 we need candidates for both of them. */
1919 if (type2 && !same_type_p (type1, type2)
1920 && TREE_CODE (type1) == TREE_CODE (type2)
1921 && (TREE_CODE (type1) == REFERENCE_TYPE
1922 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1923 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1924 || TYPE_PTRMEMFUNC_P (type1)
1925 || IS_AGGR_TYPE (type1)
1926 || TREE_CODE (type1) == ENUMERAL_TYPE))
1928 build_builtin_candidate
1929 (candidates, fnname, type1, type1, args, argtypes, flags);
1930 build_builtin_candidate
1931 (candidates, fnname, type2, type2, args, argtypes, flags);
1935 build_builtin_candidate
1936 (candidates, fnname, type1, type2, args, argtypes, flags);
1940 type_decays_to (tree type)
1942 if (TREE_CODE (type) == ARRAY_TYPE)
1943 return build_pointer_type (TREE_TYPE (type));
1944 if (TREE_CODE (type) == FUNCTION_TYPE)
1945 return build_pointer_type (type);
1949 /* There are three conditions of builtin candidates:
1951 1) bool-taking candidates. These are the same regardless of the input.
1952 2) pointer-pair taking candidates. These are generated for each type
1953 one of the input types converts to.
1954 3) arithmetic candidates. According to the standard, we should generate
1955 all of these, but I'm trying not to...
1957 Here we generate a superset of the possible candidates for this particular
1958 case. That is a subset of the full set the standard defines, plus some
1959 other cases which the standard disallows. add_builtin_candidate will
1960 filter out the invalid set. */
1963 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
1964 enum tree_code code2, tree fnname, tree *args,
1969 tree type, argtypes[3];
1970 /* TYPES[i] is the set of possible builtin-operator parameter types
1971 we will consider for the Ith argument. These are represented as
1972 a TREE_LIST; the TREE_VALUE of each node is the potential
1976 for (i = 0; i < 3; ++i)
1979 argtypes[i] = lvalue_type (args[i]);
1981 argtypes[i] = NULL_TREE;
1986 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1987 and VQ is either volatile or empty, there exist candidate operator
1988 functions of the form
1989 VQ T& operator++(VQ T&); */
1991 case POSTINCREMENT_EXPR:
1992 case PREINCREMENT_EXPR:
1993 case POSTDECREMENT_EXPR:
1994 case PREDECREMENT_EXPR:
1999 /* 24There also exist candidate operator functions of the form
2000 bool operator!(bool);
2001 bool operator&&(bool, bool);
2002 bool operator||(bool, bool); */
2004 case TRUTH_NOT_EXPR:
2005 build_builtin_candidate
2006 (candidates, fnname, boolean_type_node,
2007 NULL_TREE, args, argtypes, flags);
2010 case TRUTH_ORIF_EXPR:
2011 case TRUTH_ANDIF_EXPR:
2012 build_builtin_candidate
2013 (candidates, fnname, boolean_type_node,
2014 boolean_type_node, args, argtypes, flags);
2036 types[0] = types[1] = NULL_TREE;
2038 for (i = 0; i < 2; ++i)
2042 else if (IS_AGGR_TYPE (argtypes[i]))
2046 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2049 convs = lookup_conversions (argtypes[i]);
2051 if (code == COND_EXPR)
2053 if (real_lvalue_p (args[i]))
2054 types[i] = tree_cons
2055 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2057 types[i] = tree_cons
2058 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2064 for (; convs; convs = TREE_CHAIN (convs))
2066 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2069 && (TREE_CODE (type) != REFERENCE_TYPE
2070 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2073 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2074 types[i] = tree_cons (NULL_TREE, type, types[i]);
2076 type = non_reference (type);
2077 if (i != 0 || ! ref1)
2079 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2080 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2081 types[i] = tree_cons (NULL_TREE, type, types[i]);
2082 if (INTEGRAL_TYPE_P (type))
2083 type = type_promotes_to (type);
2086 if (! value_member (type, types[i]))
2087 types[i] = tree_cons (NULL_TREE, type, types[i]);
2092 if (code == COND_EXPR && real_lvalue_p (args[i]))
2093 types[i] = tree_cons
2094 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2095 type = non_reference (argtypes[i]);
2096 if (i != 0 || ! ref1)
2098 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2099 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2100 types[i] = tree_cons (NULL_TREE, type, types[i]);
2101 if (INTEGRAL_TYPE_P (type))
2102 type = type_promotes_to (type);
2104 types[i] = tree_cons (NULL_TREE, type, types[i]);
2108 /* Run through the possible parameter types of both arguments,
2109 creating candidates with those parameter types. */
2110 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2113 for (type = types[1]; type; type = TREE_CHAIN (type))
2114 add_builtin_candidate
2115 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2116 TREE_VALUE (type), args, argtypes, flags);
2118 add_builtin_candidate
2119 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2120 NULL_TREE, args, argtypes, flags);
2127 /* If TMPL can be successfully instantiated as indicated by
2128 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2130 TMPL is the template. EXPLICIT_TARGS are any explicit template
2131 arguments. ARGLIST is the arguments provided at the call-site.
2132 The RETURN_TYPE is the desired type for conversion operators. If
2133 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2134 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2135 add_conv_candidate. */
2137 static struct z_candidate*
2138 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2139 tree ctype, tree explicit_targs, tree arglist,
2140 tree return_type, tree access_path,
2141 tree conversion_path, int flags, tree obj,
2142 unification_kind_t strict)
2144 int ntparms = DECL_NTPARMS (tmpl);
2145 tree targs = make_tree_vec (ntparms);
2146 tree args_without_in_chrg = arglist;
2147 struct z_candidate *cand;
2151 /* We don't do deduction on the in-charge parameter, the VTT
2152 parameter or 'this'. */
2153 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2154 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2156 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2157 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2158 && TYPE_USES_VIRTUAL_BASECLASSES (DECL_CONTEXT (tmpl)))
2159 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2161 i = fn_type_unification (tmpl, explicit_targs, targs,
2162 args_without_in_chrg,
2163 return_type, strict, -1);
2168 fn = instantiate_template (tmpl, targs, tf_none);
2169 if (fn == error_mark_node)
2174 A member function template is never instantiated to perform the
2175 copy of a class object to an object of its class type.
2177 It's a little unclear what this means; the standard explicitly
2178 does allow a template to be used to copy a class. For example,
2183 template <class T> A(const T&);
2186 void g () { A a (f ()); }
2188 the member template will be used to make the copy. The section
2189 quoted above appears in the paragraph that forbids constructors
2190 whose only parameter is (a possibly cv-qualified variant of) the
2191 class type, and a logical interpretation is that the intent was
2192 to forbid the instantiation of member templates which would then
2194 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2196 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2197 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2202 if (obj != NULL_TREE)
2203 /* Aha, this is a conversion function. */
2204 cand = add_conv_candidate (candidates, fn, obj, access_path,
2205 conversion_path, arglist);
2207 cand = add_function_candidate (candidates, fn, ctype,
2208 arglist, access_path,
2209 conversion_path, flags);
2210 if (DECL_TI_TEMPLATE (fn) != tmpl)
2211 /* This situation can occur if a member template of a template
2212 class is specialized. Then, instantiate_template might return
2213 an instantiation of the specialization, in which case the
2214 DECL_TI_TEMPLATE field will point at the original
2215 specialization. For example:
2217 template <class T> struct S { template <class U> void f(U);
2218 template <> void f(int) {}; };
2222 Here, TMPL will be template <class U> S<double>::f(U).
2223 And, instantiate template will give us the specialization
2224 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2225 for this will point at template <class T> template <> S<T>::f(int),
2226 so that we can find the definition. For the purposes of
2227 overload resolution, however, we want the original TMPL. */
2228 cand->template = tree_cons (tmpl, targs, NULL_TREE);
2230 cand->template = DECL_TEMPLATE_INFO (fn);
2236 static struct z_candidate *
2237 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2238 tree explicit_targs, tree arglist, tree return_type,
2239 tree access_path, tree conversion_path, int flags,
2240 unification_kind_t strict)
2243 add_template_candidate_real (candidates, tmpl, ctype,
2244 explicit_targs, arglist, return_type,
2245 access_path, conversion_path,
2246 flags, NULL_TREE, strict);
2250 static struct z_candidate *
2251 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2252 tree obj, tree arglist, tree return_type,
2253 tree access_path, tree conversion_path)
2256 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2257 arglist, return_type, access_path,
2258 conversion_path, 0, obj, DEDUCE_CONV);
2261 /* The CANDS are the set of candidates that were considered for
2262 overload resolution. Return the set of viable candidates. If none
2263 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2264 is true if a candidate should be considered viable only if it is
2267 static struct z_candidate*
2268 splice_viable (struct z_candidate *cands,
2272 struct z_candidate *viable;
2273 struct z_candidate **last_viable;
2274 struct z_candidate **cand;
2277 last_viable = &viable;
2278 *any_viable_p = false;
2283 struct z_candidate *c = *cand;
2284 if (strict_p ? c->viable == 1 : c->viable)
2289 last_viable = &c->next;
2290 *any_viable_p = true;
2296 return viable ? viable : cands;
2300 any_strictly_viable (struct z_candidate *cands)
2302 for (; cands; cands = cands->next)
2303 if (cands->viable == 1)
2309 build_this (tree obj)
2311 /* Fix this to work on non-lvalues. */
2312 return build_unary_op (ADDR_EXPR, obj, 0);
2315 /* Returns true iff functions are equivalent. Equivalent functions are
2316 not '==' only if one is a function-local extern function or if
2317 both are extern "C". */
2320 equal_functions (tree fn1, tree fn2)
2322 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2323 || DECL_EXTERN_C_FUNCTION_P (fn1))
2324 return decls_match (fn1, fn2);
2328 /* Print information about one overload candidate CANDIDATE. MSGSTR
2329 is the text to print before the candidate itself.
2331 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2332 to have been run through gettext by the caller. This wart makes
2333 life simpler in print_z_candidates and for the translators. */
2336 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2338 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2340 if (TREE_VEC_LENGTH (candidate->convs) == 3)
2341 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2342 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
2343 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)),
2344 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 2)));
2345 else if (TREE_VEC_LENGTH (candidate->convs) == 2)
2346 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2347 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
2348 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)));
2350 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2351 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)));
2353 else if (TYPE_P (candidate->fn))
2354 inform ("%s %T <conversion>", msgstr, candidate->fn);
2355 else if (candidate->viable == -1)
2356 inform ("%H%s %+#D <near match>",
2357 &DECL_SOURCE_LOCATION (candidate->fn), msgstr, candidate->fn);
2359 inform ("%H%s %+#D",
2360 &DECL_SOURCE_LOCATION (candidate->fn), msgstr, candidate->fn);
2364 print_z_candidates (struct z_candidate *candidates)
2367 struct z_candidate *cand1;
2368 struct z_candidate **cand2;
2370 /* There may be duplicates in the set of candidates. We put off
2371 checking this condition as long as possible, since we have no way
2372 to eliminate duplicates from a set of functions in less than n^2
2373 time. Now we are about to emit an error message, so it is more
2374 permissible to go slowly. */
2375 for (cand1 = candidates; cand1; cand1 = cand1->next)
2377 tree fn = cand1->fn;
2378 /* Skip builtin candidates and conversion functions. */
2379 if (TREE_CODE (fn) != FUNCTION_DECL)
2381 cand2 = &cand1->next;
2384 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2385 && equal_functions (fn, (*cand2)->fn))
2386 *cand2 = (*cand2)->next;
2388 cand2 = &(*cand2)->next;
2395 str = _("candidates are:");
2396 print_z_candidate (str, candidates);
2397 if (candidates->next)
2399 /* Indent successive candidates by the width of the translation
2400 of the above string. */
2401 size_t len = gcc_gettext_width (str) + 1;
2402 char *spaces = alloca (len);
2403 memset (spaces, ' ', len-1);
2404 spaces[len - 1] = '\0';
2406 candidates = candidates->next;
2409 print_z_candidate (spaces, candidates);
2410 candidates = candidates->next;
2416 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2417 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2418 the result of the conversion function to convert it to the final
2419 desired type. Merge the the two sequences into a single sequence,
2420 and return the merged sequence. */
2423 merge_conversion_sequences (tree user_seq, tree std_seq)
2427 my_friendly_assert (TREE_CODE (user_seq) == USER_CONV,
2430 /* Find the end of the second conversion sequence. */
2432 while (TREE_CODE (*t) != IDENTITY_CONV)
2433 t = &TREE_OPERAND (*t, 0);
2435 /* Replace the identity conversion with the user conversion
2439 /* The entire sequence is a user-conversion sequence. */
2440 ICS_USER_FLAG (std_seq) = 1;
2445 /* Returns the best overload candidate to perform the requested
2446 conversion. This function is used for three the overloading situations
2447 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2448 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2449 per [dcl.init.ref], so we ignore temporary bindings. */
2451 static struct z_candidate *
2452 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2454 struct z_candidate *candidates, *cand;
2455 tree fromtype = TREE_TYPE (expr);
2456 tree ctors = NULL_TREE, convs = NULL_TREE;
2457 tree args = NULL_TREE;
2460 /* We represent conversion within a hierarchy using RVALUE_CONV and
2461 BASE_CONV, as specified by [over.best.ics]; these become plain
2462 constructor calls, as specified in [dcl.init]. */
2463 my_friendly_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2464 || !DERIVED_FROM_P (totype, fromtype), 20011226);
2466 if (IS_AGGR_TYPE (totype))
2467 ctors = lookup_fnfields (TYPE_BINFO (totype),
2468 complete_ctor_identifier,
2471 if (IS_AGGR_TYPE (fromtype))
2472 convs = lookup_conversions (fromtype);
2475 flags |= LOOKUP_NO_CONVERSION;
2481 ctors = BASELINK_FUNCTIONS (ctors);
2483 t = build_int_2 (0, 0);
2484 TREE_TYPE (t) = build_pointer_type (totype);
2485 args = build_tree_list (NULL_TREE, expr);
2486 /* We should never try to call the abstract or base constructor
2488 my_friendly_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2489 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)),
2491 args = tree_cons (NULL_TREE, t, args);
2493 for (; ctors; ctors = OVL_NEXT (ctors))
2495 tree ctor = OVL_CURRENT (ctors);
2496 if (DECL_NONCONVERTING_P (ctor))
2499 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2500 cand = add_template_candidate (&candidates, ctor, totype,
2501 NULL_TREE, args, NULL_TREE,
2502 TYPE_BINFO (totype),
2503 TYPE_BINFO (totype),
2507 cand = add_function_candidate (&candidates, ctor, totype,
2508 args, TYPE_BINFO (totype),
2509 TYPE_BINFO (totype),
2513 cand->second_conv = build1 (IDENTITY_CONV, totype, NULL_TREE);
2517 args = build_tree_list (NULL_TREE, build_this (expr));
2519 for (; convs; convs = TREE_CHAIN (convs))
2522 tree conversion_path = TREE_PURPOSE (convs);
2523 int convflags = LOOKUP_NO_CONVERSION;
2525 /* If we are called to convert to a reference type, we are trying to
2526 find an lvalue binding, so don't even consider temporaries. If
2527 we don't find an lvalue binding, the caller will try again to
2528 look for a temporary binding. */
2529 if (TREE_CODE (totype) == REFERENCE_TYPE)
2530 convflags |= LOOKUP_NO_TEMP_BIND;
2532 for (fns = TREE_VALUE (convs); fns; fns = OVL_NEXT (fns))
2534 tree fn = OVL_CURRENT (fns);
2536 /* [over.match.funcs] For conversion functions, the function
2537 is considered to be a member of the class of the implicit
2538 object argument for the purpose of defining the type of
2539 the implicit object parameter.
2541 So we pass fromtype as CTYPE to add_*_candidate. */
2543 if (TREE_CODE (fn) == TEMPLATE_DECL)
2544 cand = add_template_candidate (&candidates, fn, fromtype,
2547 TYPE_BINFO (fromtype),
2552 cand = add_function_candidate (&candidates, fn, fromtype,
2554 TYPE_BINFO (fromtype),
2560 tree ics = implicit_conversion (totype,
2561 TREE_TYPE (TREE_TYPE (cand->fn)),
2564 cand->second_conv = ics;
2566 if (ics == NULL_TREE)
2568 else if (candidates->viable == 1 && ICS_BAD_FLAG (ics))
2574 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2578 cand = tourney (candidates);
2581 if (flags & LOOKUP_COMPLAIN)
2583 error ("conversion from `%T' to `%T' is ambiguous",
2585 print_z_candidates (candidates);
2588 cand = candidates; /* any one will do */
2589 cand->second_conv = build1 (AMBIG_CONV, totype, expr);
2590 ICS_USER_FLAG (cand->second_conv) = 1;
2591 if (!any_strictly_viable (candidates))
2592 ICS_BAD_FLAG (cand->second_conv) = 1;
2593 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2594 ambiguous conversion is no worse than another user-defined
2600 /* Build the user conversion sequence. */
2603 (DECL_CONSTRUCTOR_P (cand->fn)
2604 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2605 build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
2606 TREE_OPERAND (convs, 1) = build_zc_wrapper (cand);
2608 /* Combine it with the second conversion sequence. */
2609 cand->second_conv = merge_conversion_sequences (convs,
2612 if (cand->viable == -1)
2613 ICS_BAD_FLAG (cand->second_conv) = 1;
2619 build_user_type_conversion (tree totype, tree expr, int flags)
2621 struct z_candidate *cand
2622 = build_user_type_conversion_1 (totype, expr, flags);
2626 if (TREE_CODE (cand->second_conv) == AMBIG_CONV)
2627 return error_mark_node;
2628 return convert_from_reference (convert_like (cand->second_conv, expr));
2633 /* Do any initial processing on the arguments to a function call. */
2636 resolve_args (tree args)
2639 for (t = args; t; t = TREE_CHAIN (t))
2641 tree arg = TREE_VALUE (t);
2643 if (arg == error_mark_node)
2644 return error_mark_node;
2645 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2647 error ("invalid use of void expression");
2648 return error_mark_node;
2650 arg = convert_from_reference (arg);
2651 TREE_VALUE (t) = arg;
2656 /* Perform overload resolution on FN, which is called with the ARGS.
2658 Return the candidate function selected by overload resolution, or
2659 NULL if the event that overload resolution failed. In the case
2660 that overload resolution fails, *CANDIDATES will be the set of
2661 candidates considered, and ANY_VIABLE_P will be set to true or
2662 false to indicate whether or not any of the candidates were
2665 The ARGS should already have gone through RESOLVE_ARGS before this
2666 function is called. */
2668 static struct z_candidate *
2669 perform_overload_resolution (tree fn,
2671 struct z_candidate **candidates,
2674 struct z_candidate *cand;
2675 tree explicit_targs = NULL_TREE;
2676 int template_only = 0;
2679 *any_viable_p = true;
2681 /* Check FN and ARGS. */
2682 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
2683 || TREE_CODE (fn) == TEMPLATE_DECL
2684 || TREE_CODE (fn) == OVERLOAD
2685 || TREE_CODE (fn) == TEMPLATE_ID_EXPR,
2687 my_friendly_assert (!args || TREE_CODE (args) == TREE_LIST,
2690 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2692 explicit_targs = TREE_OPERAND (fn, 1);
2693 fn = TREE_OPERAND (fn, 0);
2697 /* Add the various candidate functions. */
2698 add_candidates (fn, args, explicit_targs, template_only,
2699 /*conversion_path=*/NULL_TREE,
2700 /*access_path=*/NULL_TREE,
2704 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2708 cand = tourney (*candidates);
2712 /* Return an expression for a call to FN (a namespace-scope function,
2713 or a static member function) with the ARGS. */
2716 build_new_function_call (tree fn, tree args)
2718 struct z_candidate *candidates, *cand;
2721 args = resolve_args (args);
2722 if (args == error_mark_node)
2723 return error_mark_node;
2725 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2729 if (!any_viable_p && candidates && ! candidates->next)
2730 return build_function_call (candidates->fn, args);
2731 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2732 fn = TREE_OPERAND (fn, 0);
2734 error ("no matching function for call to `%D(%A)'",
2735 DECL_NAME (OVL_CURRENT (fn)), args);
2737 error ("call of overloaded `%D(%A)' is ambiguous",
2738 DECL_NAME (OVL_CURRENT (fn)), args);
2740 print_z_candidates (candidates);
2741 return error_mark_node;
2744 return build_over_call (cand, LOOKUP_NORMAL);
2747 /* Build a call to a global operator new. FNNAME is the name of the
2748 operator (either "operator new" or "operator new[]") and ARGS are
2749 the arguments provided. *SIZE points to the total number of bytes
2750 required by the allocation, and is updated if that is changed here.
2751 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2752 function determines that no cookie should be used, after all,
2753 *COOKIE_SIZE is set to NULL_TREE. */
2756 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2759 struct z_candidate *candidates;
2760 struct z_candidate *cand;
2763 args = tree_cons (NULL_TREE, *size, args);
2764 args = resolve_args (args);
2765 if (args == error_mark_node)
2768 fns = lookup_function_nonclass (fnname, args);
2770 /* Figure out what function is being called. */
2771 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2773 /* If no suitable function could be found, issue an error message
2778 error ("no matching function for call to `%D(%A)'",
2779 DECL_NAME (OVL_CURRENT (fns)), args);
2781 error ("call of overloaded `%D(%A)' is ambiguous",
2782 DECL_NAME (OVL_CURRENT (fns)), args);
2784 print_z_candidates (candidates);
2785 return error_mark_node;
2788 /* If a cookie is required, add some extra space. Whether
2789 or not a cookie is required cannot be determined until
2790 after we know which function was called. */
2793 bool use_cookie = true;
2794 if (!abi_version_at_least (2))
2796 tree placement = TREE_CHAIN (args);
2797 /* In G++ 3.2, the check was implemented incorrectly; it
2798 looked at the placement expression, rather than the
2799 type of the function. */
2800 if (placement && !TREE_CHAIN (placement)
2801 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2809 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2810 /* Skip the size_t parameter. */
2811 arg_types = TREE_CHAIN (arg_types);
2812 /* Check the remaining parameters (if any). */
2814 && TREE_CHAIN (arg_types) == void_list_node
2815 && same_type_p (TREE_VALUE (arg_types),
2819 /* If we need a cookie, adjust the number of bytes allocated. */
2822 /* Update the total size. */
2823 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2824 /* Update the argument list to reflect the adjusted size. */
2825 TREE_VALUE (args) = *size;
2828 *cookie_size = NULL_TREE;
2831 /* Build the CALL_EXPR. */
2832 return build_over_call (cand, LOOKUP_NORMAL);
2836 build_object_call (tree obj, tree args)
2838 struct z_candidate *candidates = 0, *cand;
2839 tree fns, convs, mem_args = NULL_TREE;
2840 tree type = TREE_TYPE (obj);
2843 if (TYPE_PTRMEMFUNC_P (type))
2845 /* It's no good looking for an overloaded operator() on a
2846 pointer-to-member-function. */
2847 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2848 return error_mark_node;
2851 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2852 if (fns == error_mark_node)
2853 return error_mark_node;
2855 args = resolve_args (args);
2857 if (args == error_mark_node)
2858 return error_mark_node;
2862 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2863 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2865 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2867 tree fn = OVL_CURRENT (fns);
2868 if (TREE_CODE (fn) == TEMPLATE_DECL)
2869 add_template_candidate (&candidates, fn, base, NULL_TREE,
2870 mem_args, NULL_TREE,
2873 LOOKUP_NORMAL, DEDUCE_CALL);
2875 add_function_candidate
2876 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2877 TYPE_BINFO (type), LOOKUP_NORMAL);
2881 convs = lookup_conversions (type);
2883 for (; convs; convs = TREE_CHAIN (convs))
2885 tree fns = TREE_VALUE (convs);
2886 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2888 if ((TREE_CODE (totype) == POINTER_TYPE
2889 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2890 || (TREE_CODE (totype) == REFERENCE_TYPE
2891 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2892 || (TREE_CODE (totype) == REFERENCE_TYPE
2893 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2894 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2895 for (; fns; fns = OVL_NEXT (fns))
2897 tree fn = OVL_CURRENT (fns);
2898 if (TREE_CODE (fn) == TEMPLATE_DECL)
2899 add_template_conv_candidate
2900 (&candidates, fn, obj, args, totype,
2901 /*access_path=*/NULL_TREE,
2902 /*conversion_path=*/NULL_TREE);
2904 add_conv_candidate (&candidates, fn, obj, args,
2905 /*conversion_path=*/NULL_TREE,
2906 /*access_path=*/NULL_TREE);
2910 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2913 error ("no match for call to `(%T) (%A)'", TREE_TYPE (obj), args);
2914 print_z_candidates (candidates);
2915 return error_mark_node;
2918 cand = tourney (candidates);
2921 error ("call of `(%T) (%A)' is ambiguous", TREE_TYPE (obj), args);
2922 print_z_candidates (candidates);
2923 return error_mark_node;
2926 /* Since cand->fn will be a type, not a function, for a conversion
2927 function, we must be careful not to unconditionally look at
2929 if (TREE_CODE (cand->fn) == FUNCTION_DECL
2930 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
2931 return build_over_call (cand, LOOKUP_NORMAL);
2933 obj = convert_like_with_context
2934 (TREE_VEC_ELT (cand->convs, 0), obj, cand->fn, -1);
2937 return build_function_call (obj, args);
2941 op_error (enum tree_code code, enum tree_code code2,
2942 tree arg1, tree arg2, tree arg3, const char *problem)
2946 if (code == MODIFY_EXPR)
2947 opname = assignment_operator_name_info[code2].name;
2949 opname = operator_name_info[code].name;
2954 error ("%s for ternary 'operator?:' in '%E ? %E : %E'",
2955 problem, arg1, arg2, arg3);
2958 case POSTINCREMENT_EXPR:
2959 case POSTDECREMENT_EXPR:
2960 error ("%s for 'operator%s' in '%E%s'", problem, opname, arg1, opname);
2964 error ("%s for 'operator[]' in '%E[%E]'", problem, arg1, arg2);
2969 error ("%s for '%s' in '%s %E'", problem, opname, opname, arg1);
2974 error ("%s for 'operator%s' in '%E %s %E'",
2975 problem, opname, arg1, opname, arg2);
2977 error ("%s for 'operator%s' in '%s%E'",
2978 problem, opname, opname, arg1);
2983 /* Return the implicit conversion sequence that could be used to
2984 convert E1 to E2 in [expr.cond]. */
2987 conditional_conversion (tree e1, tree e2)
2989 tree t1 = non_reference (TREE_TYPE (e1));
2990 tree t2 = non_reference (TREE_TYPE (e2));
2996 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
2997 implicitly converted (clause _conv_) to the type "reference to
2998 T2", subject to the constraint that in the conversion the
2999 reference must bind directly (_dcl.init.ref_) to E1. */
3000 if (real_lvalue_p (e2))
3002 conv = implicit_conversion (build_reference_type (t2),
3005 LOOKUP_NO_TEMP_BIND);
3012 If E1 and E2 have class type, and the underlying class types are
3013 the same or one is a base class of the other: E1 can be converted
3014 to match E2 if the class of T2 is the same type as, or a base
3015 class of, the class of T1, and the cv-qualification of T2 is the
3016 same cv-qualification as, or a greater cv-qualification than, the
3017 cv-qualification of T1. If the conversion is applied, E1 is
3018 changed to an rvalue of type T2 that still refers to the original
3019 source class object (or the appropriate subobject thereof).
3021 FIXME we can't express an rvalue that refers to the original object;
3022 we have to create a new one. */
3023 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3024 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3026 if (good_base && at_least_as_qualified_p (t2, t1))
3028 conv = build1 (IDENTITY_CONV, t1, e1);
3029 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3030 TYPE_MAIN_VARIANT (t2)))
3032 conv = build_conv (BASE_CONV, t2, conv);
3033 NEED_TEMPORARY_P (conv) = 1;
3036 conv = build_conv (RVALUE_CONV, t2, conv);
3045 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3046 converted to the type that expression E2 would have if E2 were
3047 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3048 return implicit_conversion (t2, t1, e1, LOOKUP_NORMAL);
3051 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3052 arguments to the conditional expression. */
3055 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3060 tree result_type = NULL_TREE;
3061 bool lvalue_p = true;
3062 struct z_candidate *candidates = 0;
3063 struct z_candidate *cand;
3065 /* As a G++ extension, the second argument to the conditional can be
3066 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3067 c'.) If the second operand is omitted, make sure it is
3068 calculated only once. */
3072 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3074 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3075 if (real_lvalue_p (arg1))
3076 arg2 = arg1 = stabilize_reference (arg1);
3078 arg2 = arg1 = save_expr (arg1);
3083 The first expr ession is implicitly converted to bool (clause
3085 arg1 = perform_implicit_conversion (boolean_type_node, arg1);
3087 /* If something has already gone wrong, just pass that fact up the
3089 if (error_operand_p (arg1)
3090 || error_operand_p (arg2)
3091 || error_operand_p (arg3))
3092 return error_mark_node;
3096 If either the second or the third operand has type (possibly
3097 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3098 array-to-pointer (_conv.array_), and function-to-pointer
3099 (_conv.func_) standard conversions are performed on the second
3100 and third operands. */
3101 arg2_type = TREE_TYPE (arg2);
3102 arg3_type = TREE_TYPE (arg3);
3103 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3105 /* Do the conversions. We don't these for `void' type arguments
3106 since it can't have any effect and since decay_conversion
3107 does not handle that case gracefully. */
3108 if (!VOID_TYPE_P (arg2_type))
3109 arg2 = decay_conversion (arg2);
3110 if (!VOID_TYPE_P (arg3_type))
3111 arg3 = decay_conversion (arg3);
3112 arg2_type = TREE_TYPE (arg2);
3113 arg3_type = TREE_TYPE (arg3);
3117 One of the following shall hold:
3119 --The second or the third operand (but not both) is a
3120 throw-expression (_except.throw_); the result is of the
3121 type of the other and is an rvalue.
3123 --Both the second and the third operands have type void; the
3124 result is of type void and is an rvalue. */
3125 if ((TREE_CODE (arg2) == THROW_EXPR)
3126 ^ (TREE_CODE (arg3) == THROW_EXPR))
3127 result_type = ((TREE_CODE (arg2) == THROW_EXPR)
3128 ? arg3_type : arg2_type);
3129 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3130 result_type = void_type_node;
3133 error ("`%E' has type `void' and is not a throw-expression",
3134 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3135 return error_mark_node;
3139 goto valid_operands;
3143 Otherwise, if the second and third operand have different types,
3144 and either has (possibly cv-qualified) class type, an attempt is
3145 made to convert each of those operands to the type of the other. */
3146 else if (!same_type_p (arg2_type, arg3_type)
3147 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3149 tree conv2 = conditional_conversion (arg2, arg3);
3150 tree conv3 = conditional_conversion (arg3, arg2);
3154 If both can be converted, or one can be converted but the
3155 conversion is ambiguous, the program is ill-formed. If
3156 neither can be converted, the operands are left unchanged and
3157 further checking is performed as described below. If exactly
3158 one conversion is possible, that conversion is applied to the
3159 chosen operand and the converted operand is used in place of
3160 the original operand for the remainder of this section. */
3161 if ((conv2 && !ICS_BAD_FLAG (conv2)
3162 && conv3 && !ICS_BAD_FLAG (conv3))
3163 || (conv2 && TREE_CODE (conv2) == AMBIG_CONV)
3164 || (conv3 && TREE_CODE (conv3) == AMBIG_CONV))
3166 error ("operands to ?: have different types");
3167 return error_mark_node;
3169 else if (conv2 && !ICS_BAD_FLAG (conv2))
3171 arg2 = convert_like (conv2, arg2);
3172 arg2 = convert_from_reference (arg2);
3173 if (!same_type_p (TREE_TYPE (arg2), arg3_type)
3174 && CLASS_TYPE_P (arg3_type))
3175 /* The types need to match if we're converting to a class type.
3176 If not, we don't care about cv-qual mismatches, since
3177 non-class rvalues are not cv-qualified. */
3179 arg2_type = TREE_TYPE (arg2);
3181 else if (conv3 && !ICS_BAD_FLAG (conv3))
3183 arg3 = convert_like (conv3, arg3);
3184 arg3 = convert_from_reference (arg3);
3185 if (!same_type_p (TREE_TYPE (arg3), arg2_type)
3186 && CLASS_TYPE_P (arg2_type))
3188 arg3_type = TREE_TYPE (arg3);
3194 If the second and third operands are lvalues and have the same
3195 type, the result is of that type and is an lvalue. */
3196 if (real_lvalue_p (arg2)
3197 && real_lvalue_p (arg3)
3198 && same_type_p (arg2_type, arg3_type))
3200 result_type = arg2_type;
3201 goto valid_operands;
3206 Otherwise, the result is an rvalue. If the second and third
3207 operand do not have the same type, and either has (possibly
3208 cv-qualified) class type, overload resolution is used to
3209 determine the conversions (if any) to be applied to the operands
3210 (_over.match.oper_, _over.built_). */
3212 if (!same_type_p (arg2_type, arg3_type)
3213 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3219 /* Rearrange the arguments so that add_builtin_candidate only has
3220 to know about two args. In build_builtin_candidates, the
3221 arguments are unscrambled. */
3225 add_builtin_candidates (&candidates,
3228 ansi_opname (COND_EXPR),
3234 If the overload resolution fails, the program is
3236 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3239 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3240 print_z_candidates (candidates);
3241 return error_mark_node;
3243 cand = tourney (candidates);
3246 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3247 print_z_candidates (candidates);
3248 return error_mark_node;
3253 Otherwise, the conversions thus determined are applied, and
3254 the converted operands are used in place of the original
3255 operands for the remainder of this section. */
3256 conv = TREE_VEC_ELT (cand->convs, 0);
3257 arg1 = convert_like (conv, arg1);
3258 conv = TREE_VEC_ELT (cand->convs, 1);
3259 arg2 = convert_like (conv, arg2);
3260 conv = TREE_VEC_ELT (cand->convs, 2);
3261 arg3 = convert_like (conv, arg3);
3266 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3267 and function-to-pointer (_conv.func_) standard conversions are
3268 performed on the second and third operands.
3270 We need to force the lvalue-to-rvalue conversion here for class types,
3271 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3272 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3275 We use ocp_convert rather than build_user_type_conversion because the
3276 latter returns NULL_TREE on failure, while the former gives an error. */
3278 arg2 = force_rvalue (arg2);
3279 arg2_type = TREE_TYPE (arg2);
3281 arg3 = force_rvalue (arg3);
3282 arg3_type = TREE_TYPE (arg3);
3284 if (arg2 == error_mark_node || arg3 == error_mark_node)
3285 return error_mark_node;
3289 After those conversions, one of the following shall hold:
3291 --The second and third operands have the same type; the result is of
3293 if (same_type_p (arg2_type, arg3_type))
3294 result_type = arg2_type;
3297 --The second and third operands have arithmetic or enumeration
3298 type; the usual arithmetic conversions are performed to bring
3299 them to a common type, and the result is of that type. */
3300 else if ((ARITHMETIC_TYPE_P (arg2_type)
3301 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3302 && (ARITHMETIC_TYPE_P (arg3_type)
3303 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3305 /* In this case, there is always a common type. */
3306 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3309 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3310 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3311 warning ("enumeral mismatch in conditional expression: `%T' vs `%T'",
3312 arg2_type, arg3_type);
3313 else if (extra_warnings
3314 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3315 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3316 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3317 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3318 warning ("enumeral and non-enumeral type in conditional expression");
3320 arg2 = perform_implicit_conversion (result_type, arg2);
3321 arg3 = perform_implicit_conversion (result_type, arg3);
3325 --The second and third operands have pointer type, or one has
3326 pointer type and the other is a null pointer constant; pointer
3327 conversions (_conv.ptr_) and qualification conversions
3328 (_conv.qual_) are performed to bring them to their composite
3329 pointer type (_expr.rel_). The result is of the composite
3332 --The second and third operands have pointer to member type, or
3333 one has pointer to member type and the other is a null pointer
3334 constant; pointer to member conversions (_conv.mem_) and
3335 qualification conversions (_conv.qual_) are performed to bring
3336 them to a common type, whose cv-qualification shall match the
3337 cv-qualification of either the second or the third operand.
3338 The result is of the common type. */
3339 else if ((null_ptr_cst_p (arg2)
3340 && (TYPE_PTR_P (arg3_type) || TYPE_PTR_TO_MEMBER_P (arg3_type)))
3341 || (null_ptr_cst_p (arg3)
3342 && (TYPE_PTR_P (arg2_type) || TYPE_PTR_TO_MEMBER_P (arg2_type)))
3343 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3344 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3345 || (TYPE_PTRMEMFUNC_P (arg2_type) && TYPE_PTRMEMFUNC_P (arg3_type)))
3347 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3348 arg3, "conditional expression");
3349 if (result_type == error_mark_node)
3350 return error_mark_node;
3351 arg2 = perform_implicit_conversion (result_type, arg2);
3352 arg3 = perform_implicit_conversion (result_type, arg3);
3357 error ("operands to ?: have different types");
3358 return error_mark_node;
3362 result = fold (build (COND_EXPR, result_type, arg1, arg2, arg3));
3363 /* We can't use result_type below, as fold might have returned a
3366 /* Expand both sides into the same slot, hopefully the target of the
3367 ?: expression. We used to check for TARGET_EXPRs here, but now we
3368 sometimes wrap them in NOP_EXPRs so the test would fail. */
3369 if (!lvalue_p && IS_AGGR_TYPE (TREE_TYPE (result)))
3370 result = get_target_expr (result);
3372 /* If this expression is an rvalue, but might be mistaken for an
3373 lvalue, we must add a NON_LVALUE_EXPR. */
3374 if (!lvalue_p && real_lvalue_p (result))
3375 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
3380 /* OPERAND is an operand to an expression. Perform necessary steps
3381 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3385 prep_operand (tree operand)
3389 operand = convert_from_reference (operand);
3390 if (CLASS_TYPE_P (TREE_TYPE (operand))
3391 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3392 /* Make sure the template type is instantiated now. */
3393 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3399 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3400 OVERLOAD) to the CANDIDATES, returning an updated list of
3401 CANDIDATES. The ARGS are the arguments provided to the call,
3402 without any implicit object parameter. The EXPLICIT_TARGS are
3403 explicit template arguments provided. TEMPLATE_ONLY is true if
3404 only template fucntions should be considered. CONVERSION_PATH,
3405 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3408 add_candidates (tree fns, tree args,
3409 tree explicit_targs, bool template_only,
3410 tree conversion_path, tree access_path,
3412 struct z_candidate **candidates)
3415 tree non_static_args;
3417 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3418 /* Delay creating the implicit this parameter until it is needed. */
3419 non_static_args = NULL_TREE;
3426 fn = OVL_CURRENT (fns);
3427 /* Figure out which set of arguments to use. */
3428 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3430 /* If this function is a non-static member, prepend the implicit
3431 object parameter. */
3432 if (!non_static_args)
3433 non_static_args = tree_cons (NULL_TREE,
3434 build_this (TREE_VALUE (args)),
3436 fn_args = non_static_args;
3439 /* Otherwise, just use the list of arguments provided. */
3442 if (TREE_CODE (fn) == TEMPLATE_DECL)
3443 add_template_candidate (candidates,
3453 else if (!template_only)
3454 add_function_candidate (candidates,
3461 fns = OVL_NEXT (fns);
3466 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3)
3468 struct z_candidate *candidates = 0, *cand;
3469 tree arglist, fnname;
3471 enum tree_code code2 = NOP_EXPR;
3476 if (error_operand_p (arg1)
3477 || error_operand_p (arg2)
3478 || error_operand_p (arg3))
3479 return error_mark_node;
3481 if (code == MODIFY_EXPR)
3483 code2 = TREE_CODE (arg3);
3485 fnname = ansi_assopname (code2);
3488 fnname = ansi_opname (code);
3490 arg1 = prep_operand (arg1);
3496 case VEC_DELETE_EXPR:
3498 /* Use build_op_new_call and build_op_delete_call instead. */
3502 return build_object_call (arg1, arg2);
3508 arg2 = prep_operand (arg2);
3509 arg3 = prep_operand (arg3);
3511 if (code == COND_EXPR)
3513 if (arg2 == NULL_TREE
3514 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3515 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3516 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3517 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3520 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3521 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3524 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3525 arg2 = integer_zero_node;
3527 arglist = NULL_TREE;
3529 arglist = tree_cons (NULL_TREE, arg3, arglist);
3531 arglist = tree_cons (NULL_TREE, arg2, arglist);
3532 arglist = tree_cons (NULL_TREE, arg1, arglist);
3534 /* Add namespace-scope operators to the list of functions to
3536 add_candidates (lookup_function_nonclass (fnname, arglist),
3537 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3538 flags, &candidates);
3539 /* Add class-member operators to the candidate set. */
3540 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3544 fns = lookup_fnfields (TYPE_BINFO (TREE_TYPE (arg1)), fnname, 1);
3545 if (fns == error_mark_node)
3548 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3550 BASELINK_BINFO (fns),
3551 TYPE_BINFO (TREE_TYPE (arg1)),
3552 flags, &candidates);
3555 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3556 to know about two args; a builtin candidate will always have a first
3557 parameter of type bool. We'll handle that in
3558 build_builtin_candidate. */
3559 if (code == COND_EXPR)
3569 args[2] = NULL_TREE;
3572 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3578 /* For these, the built-in candidates set is empty
3579 [over.match.oper]/3. We don't want non-strict matches
3580 because exact matches are always possible with built-in
3581 operators. The built-in candidate set for COMPONENT_REF
3582 would be empty too, but since there are no such built-in
3583 operators, we accept non-strict matches for them. */
3588 strict_p = pedantic;
3592 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3597 case POSTINCREMENT_EXPR:
3598 case POSTDECREMENT_EXPR:
3599 /* Look for an `operator++ (int)'. If they didn't have
3600 one, then we fall back to the old way of doing things. */
3601 if (flags & LOOKUP_COMPLAIN)
3602 pedwarn ("no `%D(int)' declared for postfix `%s', trying prefix operator instead",
3604 operator_name_info[code].name);
3605 if (code == POSTINCREMENT_EXPR)
3606 code = PREINCREMENT_EXPR;
3608 code = PREDECREMENT_EXPR;
3609 return build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE);
3611 /* The caller will deal with these. */
3620 if (flags & LOOKUP_COMPLAIN)
3622 op_error (code, code2, arg1, arg2, arg3, "no match");
3623 print_z_candidates (candidates);
3625 return error_mark_node;
3628 cand = tourney (candidates);
3631 if (flags & LOOKUP_COMPLAIN)
3633 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3634 print_z_candidates (candidates);
3636 return error_mark_node;
3639 if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3642 && fnname == ansi_assopname (NOP_EXPR)
3643 && DECL_ARTIFICIAL (cand->fn)
3645 && ! candidates->next->next)
3647 warning ("using synthesized `%#D' for copy assignment",
3649 cp_warning_at (" where cfront would use `%#D'",
3651 ? candidates->next->fn
3655 return build_over_call (cand, LOOKUP_NORMAL);
3658 /* Check for comparison of different enum types. */
3667 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3668 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3669 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3670 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3672 warning ("comparison between `%#T' and `%#T'",
3673 TREE_TYPE (arg1), TREE_TYPE (arg2));
3680 /* We need to strip any leading REF_BIND so that bitfields don't cause
3681 errors. This should not remove any important conversions, because
3682 builtins don't apply to class objects directly. */
3683 conv = TREE_VEC_ELT (cand->convs, 0);
3684 if (TREE_CODE (conv) == REF_BIND)
3685 conv = TREE_OPERAND (conv, 0);
3686 arg1 = convert_like (conv, arg1);
3689 conv = TREE_VEC_ELT (cand->convs, 1);
3690 if (TREE_CODE (conv) == REF_BIND)
3691 conv = TREE_OPERAND (conv, 0);
3692 arg2 = convert_like (conv, arg2);
3696 conv = TREE_VEC_ELT (cand->convs, 2);
3697 if (TREE_CODE (conv) == REF_BIND)
3698 conv = TREE_OPERAND (conv, 0);
3699 arg3 = convert_like (conv, arg3);
3706 return build_modify_expr (arg1, code2, arg2);
3709 return build_indirect_ref (arg1, "unary *");
3714 case TRUNC_DIV_EXPR:
3725 case TRUNC_MOD_EXPR:
3729 case TRUTH_ANDIF_EXPR:
3730 case TRUTH_ORIF_EXPR:
3731 return cp_build_binary_op (code, arg1, arg2);
3736 case TRUTH_NOT_EXPR:
3737 case PREINCREMENT_EXPR:
3738 case POSTINCREMENT_EXPR:
3739 case PREDECREMENT_EXPR:
3740 case POSTDECREMENT_EXPR:
3743 return build_unary_op (code, arg1, candidates != 0);
3746 return build_array_ref (arg1, arg2);
3749 return build_conditional_expr (arg1, arg2, arg3);
3752 return build_m_component_ref
3753 (build_indirect_ref (arg1, NULL), arg2);
3755 /* The caller will deal with these. */
3767 /* Build a call to operator delete. This has to be handled very specially,
3768 because the restrictions on what signatures match are different from all
3769 other call instances. For a normal delete, only a delete taking (void *)
3770 or (void *, size_t) is accepted. For a placement delete, only an exact
3771 match with the placement new is accepted.
3773 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3774 ADDR is the pointer to be deleted.
3775 SIZE is the size of the memory block to be deleted.
3776 FLAGS are the usual overloading flags.
3777 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3780 build_op_delete_call (enum tree_code code, tree addr, tree size,
3781 int flags, tree placement)
3783 tree fn = NULL_TREE;
3784 tree fns, fnname, argtypes, args, type;
3787 if (addr == error_mark_node)
3788 return error_mark_node;
3790 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3792 fnname = ansi_opname (code);
3794 if (IS_AGGR_TYPE (type) && ! (flags & LOOKUP_GLOBAL))
3797 If the result of the lookup is ambiguous or inaccessible, or if
3798 the lookup selects a placement deallocation function, the
3799 program is ill-formed.
3801 Therefore, we ask lookup_fnfields to complain ambout ambiguity. */
3803 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3804 if (fns == error_mark_node)
3805 return error_mark_node;
3810 if (fns == NULL_TREE)
3811 fns = lookup_name_nonclass (fnname);
3818 /* Find the allocation function that is being called. */
3819 call_expr = placement;
3820 /* Sometimes we have a COMPOUND_EXPR, rather than a simple
3822 while (TREE_CODE (call_expr) == COMPOUND_EXPR)
3823 call_expr = TREE_OPERAND (call_expr, 1);
3824 /* Extract the function. */
3825 alloc_fn = get_callee_fndecl (call_expr);
3826 my_friendly_assert (alloc_fn != NULL_TREE, 20020327);
3827 /* Then the second parm type. */
3828 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3829 /* Also the second argument. */
3830 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3834 /* First try it without the size argument. */
3835 argtypes = void_list_node;
3839 /* Strip const and volatile from addr. */
3840 addr = cp_convert (ptr_type_node, addr);
3842 /* We make two tries at finding a matching `operator delete'. On
3843 the first pass, we look for a one-operator (or placement)
3844 operator delete. If we're not doing placement delete, then on
3845 the second pass we look for a two-argument delete. */
3846 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
3848 /* Go through the `operator delete' functions looking for one
3849 with a matching type. */
3850 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
3856 /* The first argument must be "void *". */
3857 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
3858 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
3861 /* On the first pass, check the rest of the arguments. */
3864 while (argtypes && t)
3866 if (!same_type_p (TREE_VALUE (argtypes),
3869 argtypes = TREE_CHAIN (argtypes);
3872 if (!argtypes && !t)
3875 /* On the second pass, the second argument must be
3878 && same_type_p (TREE_VALUE (t), sizetype)
3879 && TREE_CHAIN (t) == void_list_node)
3883 /* If we found a match, we're done. */
3888 /* If we have a matching function, call it. */
3891 /* Make sure we have the actual function, and not an
3893 fn = OVL_CURRENT (fn);
3895 /* If the FN is a member function, make sure that it is
3897 if (DECL_CLASS_SCOPE_P (fn))
3898 perform_or_defer_access_check (TYPE_BINFO (type), fn);
3901 args = tree_cons (NULL_TREE, addr, args);
3903 args = tree_cons (NULL_TREE, addr,
3904 build_tree_list (NULL_TREE, size));
3906 return build_function_call (fn, args);
3909 /* If we are doing placement delete we do nothing if we don't find a
3910 matching op delete. */
3914 error ("no suitable `operator %s' for `%T'",
3915 operator_name_info[(int)code].name, type);
3916 return error_mark_node;
3919 /* If the current scope isn't allowed to access DECL along
3920 BASETYPE_PATH, give an error. The most derived class in
3921 BASETYPE_PATH is the one used to qualify DECL. */
3924 enforce_access (tree basetype_path, tree decl)
3926 my_friendly_assert (TREE_CODE (basetype_path) == TREE_VEC, 20030624);
3928 if (!accessible_p (basetype_path, decl))
3930 if (TREE_PRIVATE (decl))
3931 cp_error_at ("`%+#D' is private", decl);
3932 else if (TREE_PROTECTED (decl))
3933 cp_error_at ("`%+#D' is protected", decl);
3935 cp_error_at ("`%+#D' is inaccessible", decl);
3936 error ("within this context");
3943 /* Perform the conversions in CONVS on the expression EXPR. FN and
3944 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
3945 indicates the `this' argument of a method. INNER is nonzero when
3946 being called to continue a conversion chain. It is negative when a
3947 reference binding will be applied, positive otherwise. If
3948 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
3949 conversions will be emitted if appropriate. */
3952 convert_like_real (tree convs, tree expr, tree fn, int argnum, int inner,
3953 bool issue_conversion_warnings)
3957 tree totype = TREE_TYPE (convs);
3959 if (ICS_BAD_FLAG (convs)
3960 && TREE_CODE (convs) != USER_CONV
3961 && TREE_CODE (convs) != AMBIG_CONV
3962 && TREE_CODE (convs) != REF_BIND)
3965 for (; t; t = TREE_OPERAND (t, 0))
3967 if (TREE_CODE (t) == USER_CONV || !ICS_BAD_FLAG (t))
3969 expr = convert_like_real (t, expr, fn, argnum, 1,
3970 /*issue_conversion_warnings=*/false);
3973 else if (TREE_CODE (t) == AMBIG_CONV)
3974 return convert_like_real (t, expr, fn, argnum, 1,
3975 /*issue_conversion_warnings=*/false);
3976 else if (TREE_CODE (t) == IDENTITY_CONV)
3979 pedwarn ("invalid conversion from `%T' to `%T'", TREE_TYPE (expr), totype);
3981 pedwarn (" initializing argument %P of `%D'", argnum, fn);
3982 return cp_convert (totype, expr);
3985 if (issue_conversion_warnings)
3986 expr = dubious_conversion_warnings
3987 (totype, expr, "argument", fn, argnum);
3988 switch (TREE_CODE (convs))
3992 struct z_candidate *cand = USER_CONV_CAND (convs);
3993 tree convfn = cand->fn;
3996 if (DECL_CONSTRUCTOR_P (convfn))
3998 tree t = build_int_2 (0, 0);
3999 TREE_TYPE (t) = build_pointer_type (DECL_CONTEXT (convfn));
4001 args = build_tree_list (NULL_TREE, expr);
4002 if (DECL_HAS_IN_CHARGE_PARM_P (convfn)
4003 || DECL_HAS_VTT_PARM_P (convfn))
4004 /* We should never try to call the abstract or base constructor
4007 args = tree_cons (NULL_TREE, t, args);
4010 args = build_this (expr);
4011 expr = build_over_call (cand, LOOKUP_NORMAL);
4013 /* If this is a constructor or a function returning an aggr type,
4014 we need to build up a TARGET_EXPR. */
4015 if (DECL_CONSTRUCTOR_P (convfn))
4016 expr = build_cplus_new (totype, expr);
4018 /* The result of the call is then used to direct-initialize the object
4019 that is the destination of the copy-initialization. [dcl.init]
4021 Note that this step is not reflected in the conversion sequence;
4022 it affects the semantics when we actually perform the
4023 conversion, but is not considered during overload resolution.
4025 If the target is a class, that means call a ctor. */
4026 if (IS_AGGR_TYPE (totype)
4027 && (inner >= 0 || !lvalue_p (expr)))
4029 savew = warningcount, savee = errorcount;
4030 expr = build_special_member_call
4031 (NULL_TREE, complete_ctor_identifier,
4032 build_tree_list (NULL_TREE, expr), TYPE_BINFO (totype),
4033 /* Core issue 84, now a DR, says that we don't allow UDCs
4034 for these args (which deliberately breaks copy-init of an
4035 auto_ptr<Base> from an auto_ptr<Derived>). */
4036 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION);
4038 /* Tell the user where this failing constructor call came from. */
4041 if (warningcount > savew)
4043 (" initializing argument %P of `%D' from result of `%D'",
4044 argnum, fn, convfn);
4045 else if (errorcount > savee)
4047 (" initializing argument %P of `%D' from result of `%D'",
4048 argnum, fn, convfn);
4052 if (warningcount > savew)
4053 warning (" initializing temporary from result of `%D'",
4055 else if (errorcount > savee)
4056 error (" initializing temporary from result of `%D'",
4059 expr = build_cplus_new (totype, expr);
4064 if (type_unknown_p (expr))
4065 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4066 /* Convert a non-array constant variable to its underlying value, unless we
4067 are about to bind it to a reference, in which case we need to
4068 leave it as an lvalue. */
4070 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
4071 expr = decl_constant_value (expr);
4074 /* Call build_user_type_conversion again for the error. */
4075 return build_user_type_conversion
4076 (totype, TREE_OPERAND (convs, 0), LOOKUP_NORMAL);
4082 expr = convert_like_real (TREE_OPERAND (convs, 0), expr, fn, argnum,
4083 TREE_CODE (convs) == REF_BIND ? -1 : 1,
4084 /*issue_conversion_warnings=*/false);
4085 if (expr == error_mark_node)
4086 return error_mark_node;
4088 switch (TREE_CODE (convs))
4091 if (! IS_AGGR_TYPE (totype))
4093 /* else fall through */
4095 if (TREE_CODE (convs) == BASE_CONV && !NEED_TEMPORARY_P (convs))
4097 /* We are going to bind a reference directly to a base-class
4098 subobject of EXPR. */
4099 tree base_ptr = build_pointer_type (totype);
4101 /* Build an expression for `*((base*) &expr)'. */
4102 expr = build_unary_op (ADDR_EXPR, expr, 0);
4103 expr = perform_implicit_conversion (base_ptr, expr);
4104 expr = build_indirect_ref (expr, "implicit conversion");
4108 /* Copy-initialization where the cv-unqualified version of the source
4109 type is the same class as, or a derived class of, the class of the
4110 destination [is treated as direct-initialization]. [dcl.init] */
4111 savew = warningcount, savee = errorcount;
4112 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4113 build_tree_list (NULL_TREE, expr),
4114 TYPE_BINFO (totype),
4115 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING);
4118 if (warningcount > savew)
4119 warning (" initializing argument %P of `%D'", argnum, fn);
4120 else if (errorcount > savee)
4121 error (" initializing argument %P of `%D'", argnum, fn);
4123 return build_cplus_new (totype, expr);
4127 tree ref_type = totype;
4129 /* If necessary, create a temporary. */
4130 if (NEED_TEMPORARY_P (convs) || !lvalue_p (expr))
4132 tree type = TREE_TYPE (TREE_OPERAND (convs, 0));
4134 if (!CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (ref_type)))
4136 /* If the reference is volatile or non-const, we
4137 cannot create a temporary. */
4138 cp_lvalue_kind lvalue = real_lvalue_p (expr);
4140 if (lvalue & clk_bitfield)
4141 error ("cannot bind bitfield `%E' to `%T'",
4143 else if (lvalue & clk_packed)
4144 error ("cannot bind packed field `%E' to `%T'",
4147 error ("cannot bind rvalue `%E' to `%T'", expr, ref_type);
4148 return error_mark_node;
4150 expr = build_target_expr_with_type (expr, type);
4153 /* Take the address of the thing to which we will bind the
4155 expr = build_unary_op (ADDR_EXPR, expr, 1);
4156 if (expr == error_mark_node)
4157 return error_mark_node;
4159 /* Convert it to a pointer to the type referred to by the
4160 reference. This will adjust the pointer if a derived to
4161 base conversion is being performed. */
4162 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4164 /* Convert the pointer to the desired reference type. */
4165 return build_nop (ref_type, expr);
4169 return decay_conversion (expr);
4172 /* Warn about deprecated conversion if appropriate. */
4173 string_conv_p (totype, expr, 1);
4179 return ocp_convert (totype, expr, CONV_IMPLICIT,
4180 LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
4183 /* Build a call to __builtin_trap which can be used in an expression. */
4186 call_builtin_trap (void)
4188 tree fn = get_identifier ("__builtin_trap");
4189 if (IDENTIFIER_GLOBAL_VALUE (fn))
4190 fn = IDENTIFIER_GLOBAL_VALUE (fn);
4194 fn = build_call (fn, NULL_TREE);
4195 fn = build (COMPOUND_EXPR, integer_type_node, fn, integer_zero_node);
4199 /* ARG is being passed to a varargs function. Perform any conversions
4200 required. Return the converted value. */
4203 convert_arg_to_ellipsis (tree arg)
4207 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4208 standard conversions are performed. */
4209 arg = decay_conversion (arg);
4212 If the argument has integral or enumeration type that is subject
4213 to the integral promotions (_conv.prom_), or a floating point
4214 type that is subject to the floating point promotion
4215 (_conv.fpprom_), the value of the argument is converted to the
4216 promoted type before the call. */
4217 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4218 && (TYPE_PRECISION (TREE_TYPE (arg))
4219 < TYPE_PRECISION (double_type_node)))
4220 arg = convert_to_real (double_type_node, arg);
4221 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4222 arg = perform_integral_promotions (arg);
4224 arg = require_complete_type (arg);
4226 if (arg != error_mark_node && ! pod_type_p (TREE_TYPE (arg)))
4228 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4229 here and do a bitwise copy, but now cp_expr_size will abort if we
4231 warning ("cannot pass objects of non-POD type `%#T' through `...'; \
4232 call will abort at runtime",
4234 arg = call_builtin_trap ();
4240 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4243 build_x_va_arg (tree expr, tree type)
4245 if (processing_template_decl)
4246 return build_min (VA_ARG_EXPR, type, expr);
4248 type = complete_type_or_else (type, NULL_TREE);
4250 if (expr == error_mark_node || !type)
4251 return error_mark_node;
4253 if (! pod_type_p (type))
4255 /* Undefined behavior [expr.call] 5.2.2/7. */
4256 warning ("cannot receive objects of non-POD type `%#T' through `...'",
4260 return build_va_arg (expr, type);
4263 /* TYPE has been given to va_arg. Apply the default conversions which
4264 would have happened when passed via ellipsis. Return the promoted
4265 type, or the passed type if there is no change. */
4268 cxx_type_promotes_to (tree type)
4272 if (TREE_CODE (type) == ARRAY_TYPE)
4273 return build_pointer_type (TREE_TYPE (type));
4275 if (TREE_CODE (type) == FUNCTION_TYPE)
4276 return build_pointer_type (type);
4278 promote = type_promotes_to (type);
4279 if (same_type_p (type, promote))
4285 /* ARG is a default argument expression being passed to a parameter of
4286 the indicated TYPE, which is a parameter to FN. Do any required
4287 conversions. Return the converted value. */
4290 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4292 /* If the ARG is an unparsed default argument expression, the
4293 conversion cannot be performed. */
4294 if (TREE_CODE (arg) == DEFAULT_ARG)
4296 error ("the default argument for parameter %d of `%D' has "
4297 "not yet been parsed",
4299 return error_mark_node;
4302 if (fn && DECL_TEMPLATE_INFO (fn))
4303 arg = tsubst_default_argument (fn, type, arg);
4305 arg = break_out_target_exprs (arg);
4307 if (TREE_CODE (arg) == CONSTRUCTOR)
4309 arg = digest_init (type, arg, 0);
4310 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4311 "default argument", fn, parmnum);
4315 /* This could get clobbered by the following call. */
4316 if (TREE_HAS_CONSTRUCTOR (arg))
4317 arg = copy_node (arg);
4319 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4320 "default argument", fn, parmnum);
4321 arg = convert_for_arg_passing (type, arg);
4327 /* Returns the type which will really be used for passing an argument of
4331 type_passed_as (tree type)
4333 /* Pass classes with copy ctors by invisible reference. */
4334 if (TREE_ADDRESSABLE (type))
4335 type = build_reference_type (type);
4336 else if (PROMOTE_PROTOTYPES
4337 && INTEGRAL_TYPE_P (type)
4338 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4339 TYPE_SIZE (integer_type_node)))
4340 type = integer_type_node;
4345 /* Actually perform the appropriate conversion. */
4348 convert_for_arg_passing (tree type, tree val)
4350 if (val == error_mark_node)
4352 /* Pass classes with copy ctors by invisible reference. */
4353 else if (TREE_ADDRESSABLE (type))
4354 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4355 else if (PROMOTE_PROTOTYPES
4356 && INTEGRAL_TYPE_P (type)
4357 && INT_CST_LT_UNSIGNED (TYPE_SIZE (type),
4358 TYPE_SIZE (integer_type_node)))
4359 val = perform_integral_promotions (val);
4363 /* Subroutine of the various build_*_call functions. Overload resolution
4364 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4365 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4366 bitmask of various LOOKUP_* flags which apply to the call itself. */
4369 build_over_call (struct z_candidate *cand, int flags)
4372 tree args = cand->args;
4373 tree convs = cand->convs;
4374 tree converted_args = NULL_TREE;
4375 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4376 tree conv, arg, val;
4380 /* Give any warnings we noticed during overload resolution. */
4382 for (val = cand->warnings; val; val = TREE_CHAIN (val))
4383 joust (cand, WRAPPER_ZC (TREE_VALUE (val)), 1);
4385 if (DECL_FUNCTION_MEMBER_P (fn))
4386 perform_or_defer_access_check (cand->access_path, fn);
4388 if (args && TREE_CODE (args) != TREE_LIST)
4389 args = build_tree_list (NULL_TREE, args);
4392 /* The implicit parameters to a constructor are not considered by overload
4393 resolution, and must be of the proper type. */
4394 if (DECL_CONSTRUCTOR_P (fn))
4396 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4397 arg = TREE_CHAIN (arg);
4398 parm = TREE_CHAIN (parm);
4399 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
4400 /* We should never try to call the abstract constructor. */
4402 if (DECL_HAS_VTT_PARM_P (fn))
4404 converted_args = tree_cons
4405 (NULL_TREE, TREE_VALUE (arg), converted_args);
4406 arg = TREE_CHAIN (arg);
4407 parm = TREE_CHAIN (parm);
4410 /* Bypass access control for 'this' parameter. */
4411 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4413 tree parmtype = TREE_VALUE (parm);
4414 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4418 if (ICS_BAD_FLAG (TREE_VEC_ELT (convs, i)))
4419 pedwarn ("passing `%T' as `this' argument of `%#D' discards qualifiers",
4420 TREE_TYPE (argtype), fn);
4422 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4423 X is called for an object that is not of type X, or of a type
4424 derived from X, the behavior is undefined.
4426 So we can assume that anything passed as 'this' is non-null, and
4427 optimize accordingly. */
4428 my_friendly_assert (TREE_CODE (parmtype) == POINTER_TYPE, 19990811);
4429 /* Convert to the base in which the function was declared. */
4430 my_friendly_assert (cand->conversion_path != NULL_TREE, 20020730);
4431 converted_arg = build_base_path (PLUS_EXPR,
4433 cand->conversion_path,
4435 /* Check that the base class is accessible. */
4436 if (!accessible_base_p (TREE_TYPE (argtype),
4437 BINFO_TYPE (cand->conversion_path)))
4438 error ("`%T' is not an accessible base of `%T'",
4439 BINFO_TYPE (cand->conversion_path),
4440 TREE_TYPE (argtype));
4441 /* If fn was found by a using declaration, the conversion path
4442 will be to the derived class, not the base declaring fn. We
4443 must convert from derived to base. */
4444 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4445 TREE_TYPE (parmtype), ba_ignore, NULL);
4446 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4449 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4450 parm = TREE_CHAIN (parm);
4451 arg = TREE_CHAIN (arg);
4457 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4459 tree type = TREE_VALUE (parm);
4461 conv = TREE_VEC_ELT (convs, i);
4462 val = convert_like_with_context
4463 (conv, TREE_VALUE (arg), fn, i - is_method);
4465 val = convert_for_arg_passing (type, val);
4466 converted_args = tree_cons (NULL_TREE, val, converted_args);
4469 /* Default arguments */
4470 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4472 = tree_cons (NULL_TREE,
4473 convert_default_arg (TREE_VALUE (parm),
4474 TREE_PURPOSE (parm),
4479 for (; arg; arg = TREE_CHAIN (arg))
4481 = tree_cons (NULL_TREE,
4482 convert_arg_to_ellipsis (TREE_VALUE (arg)),
4485 converted_args = nreverse (converted_args);
4488 check_function_format (NULL, TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4491 /* Avoid actually calling copy constructors and copy assignment operators,
4494 if (! flag_elide_constructors)
4495 /* Do things the hard way. */;
4496 else if (TREE_VEC_LENGTH (convs) == 1
4497 && DECL_COPY_CONSTRUCTOR_P (fn))
4500 arg = skip_artificial_parms_for (fn, converted_args);
4501 arg = TREE_VALUE (arg);
4503 /* Pull out the real argument, disregarding const-correctness. */
4505 while (TREE_CODE (targ) == NOP_EXPR
4506 || TREE_CODE (targ) == NON_LVALUE_EXPR
4507 || TREE_CODE (targ) == CONVERT_EXPR)
4508 targ = TREE_OPERAND (targ, 0);
4509 if (TREE_CODE (targ) == ADDR_EXPR)
4511 targ = TREE_OPERAND (targ, 0);
4512 if (!same_type_ignoring_top_level_qualifiers_p
4513 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4522 arg = build_indirect_ref (arg, 0);
4524 /* [class.copy]: the copy constructor is implicitly defined even if
4525 the implementation elided its use. */
4526 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4529 /* If we're creating a temp and we already have one, don't create a
4530 new one. If we're not creating a temp but we get one, use
4531 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4532 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4533 temp or an INIT_EXPR otherwise. */
4534 if (integer_zerop (TREE_VALUE (args)))
4536 if (TREE_CODE (arg) == TARGET_EXPR)
4538 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4539 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4541 else if (TREE_CODE (arg) == TARGET_EXPR
4542 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4545 tree to = stabilize_reference
4546 (build_indirect_ref (TREE_VALUE (args), 0));
4548 val = build (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4549 address = build_unary_op (ADDR_EXPR, val, 0);
4550 /* Avoid a warning about this expression, if the address is
4552 TREE_USED (address) = 1;
4556 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4558 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4560 tree to = stabilize_reference
4561 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4563 arg = build_indirect_ref (TREE_VALUE (TREE_CHAIN (converted_args)), 0);
4564 val = build (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4570 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4572 tree t, *p = &TREE_VALUE (converted_args);
4573 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4576 my_friendly_assert (binfo && binfo != error_mark_node, 20010730);
4578 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4579 if (TREE_SIDE_EFFECTS (*p))
4580 *p = save_expr (*p);
4581 t = build_pointer_type (TREE_TYPE (fn));
4582 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4583 fn = build_java_interface_fn_ref (fn, *p);
4585 fn = build_vfn_ref (build_indirect_ref (*p, 0), DECL_VINDEX (fn));
4588 else if (DECL_INLINE (fn))
4589 fn = inline_conversion (fn);
4591 fn = build_addr_func (fn);
4593 return build_cxx_call (fn, args, converted_args);
4596 /* Build and return a call to FN, using the the CONVERTED_ARGS. ARGS
4597 gives the original form of the arguments. This function performs
4598 no overload resolution, conversion, or other high-level
4602 build_cxx_call(tree fn, tree args, tree converted_args)
4606 /* Recognize certain built-in functions so we can make tree-codes
4607 other than CALL_EXPR. We do this when it enables fold-const.c
4608 to do something useful. */
4609 if (TREE_CODE (fn) == ADDR_EXPR
4610 && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL
4611 && DECL_BUILT_IN (TREE_OPERAND (fn, 0)))
4614 exp = expand_tree_builtin (TREE_OPERAND (fn, 0), args, converted_args);
4619 fn = build_call (fn, converted_args);
4621 /* If this call might throw an exception, note that fact. */
4622 fndecl = get_callee_fndecl (fn);
4623 if ((!fndecl || !TREE_NOTHROW (fndecl))
4624 && at_function_scope_p ()
4626 cp_function_chain->can_throw = 1;
4628 /* Some built-in function calls will be evaluated at compile-time in
4632 if (VOID_TYPE_P (TREE_TYPE (fn)))
4635 fn = require_complete_type (fn);
4636 if (fn == error_mark_node)
4637 return error_mark_node;
4639 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4640 fn = build_cplus_new (TREE_TYPE (fn), fn);
4641 return convert_from_reference (fn);
4644 static GTY(()) tree java_iface_lookup_fn;
4646 /* Make an expression which yields the address of the Java interface
4647 method FN. This is achieved by generating a call to libjava's
4648 _Jv_LookupInterfaceMethodIdx(). */
4651 build_java_interface_fn_ref (tree fn, tree instance)
4653 tree lookup_args, lookup_fn, method, idx;
4654 tree klass_ref, iface, iface_ref;
4657 if (!java_iface_lookup_fn)
4659 tree endlink = build_void_list_node ();
4660 tree t = tree_cons (NULL_TREE, ptr_type_node,
4661 tree_cons (NULL_TREE, ptr_type_node,
4662 tree_cons (NULL_TREE, java_int_type_node,
4664 java_iface_lookup_fn
4665 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
4666 build_function_type (ptr_type_node, t),
4667 0, NOT_BUILT_IN, NULL, NULL_TREE);
4670 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
4671 This is the first entry in the vtable. */
4672 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
4675 /* Get the java.lang.Class pointer for the interface being called. */
4676 iface = DECL_CONTEXT (fn);
4677 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
4678 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
4679 || DECL_CONTEXT (iface_ref) != iface)
4681 error ("could not find class$ field in java interface type `%T'",
4683 return error_mark_node;
4685 iface_ref = build1 (ADDR_EXPR, build_pointer_type (iface), iface_ref);
4687 /* Determine the itable index of FN. */
4689 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
4691 if (!DECL_VIRTUAL_P (method))
4697 idx = build_int_2 (i, 0);
4699 lookup_args = tree_cons (NULL_TREE, klass_ref,
4700 tree_cons (NULL_TREE, iface_ref,
4701 build_tree_list (NULL_TREE, idx)));
4702 lookup_fn = build1 (ADDR_EXPR,
4703 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
4704 java_iface_lookup_fn);
4705 return build (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
4708 /* Returns the value to use for the in-charge parameter when making a
4709 call to a function with the indicated NAME. */
4712 in_charge_arg_for_name (tree name)
4714 if (name == base_ctor_identifier
4715 || name == base_dtor_identifier)
4716 return integer_zero_node;
4717 else if (name == complete_ctor_identifier)
4718 return integer_one_node;
4719 else if (name == complete_dtor_identifier)
4720 return integer_two_node;
4721 else if (name == deleting_dtor_identifier)
4722 return integer_three_node;
4724 /* This function should only be called with one of the names listed
4730 /* Build a call to a constructor, destructor, or an assignment
4731 operator for INSTANCE, an expression with class type. NAME
4732 indicates the special member function to call; ARGS are the
4733 arguments. BINFO indicates the base of INSTANCE that is to be
4734 passed as the `this' parameter to the member function called.
4736 FLAGS are the LOOKUP_* flags to use when processing the call.
4738 If NAME indicates a complete object constructor, INSTANCE may be
4739 NULL_TREE. In this case, the caller will call build_cplus_new to
4740 store the newly constructed object into a VAR_DECL. */
4743 build_special_member_call (tree instance, tree name, tree args,
4744 tree binfo, int flags)
4747 /* The type of the subobject to be constructed or destroyed. */
4750 my_friendly_assert (name == complete_ctor_identifier
4751 || name == base_ctor_identifier
4752 || name == complete_dtor_identifier
4753 || name == base_dtor_identifier
4754 || name == deleting_dtor_identifier
4755 || name == ansi_assopname (NOP_EXPR),
4757 my_friendly_assert (binfo != NULL_TREE, 20020712);
4759 class_type = BINFO_TYPE (binfo);
4761 /* Handle the special case where INSTANCE is NULL_TREE. */
4762 if (name == complete_ctor_identifier && !instance)
4764 instance = build_int_2 (0, 0);
4765 TREE_TYPE (instance) = build_pointer_type (class_type);
4766 instance = build1 (INDIRECT_REF, class_type, instance);
4770 if (name == complete_dtor_identifier
4771 || name == base_dtor_identifier
4772 || name == deleting_dtor_identifier)
4773 my_friendly_assert (args == NULL_TREE, 20020712);
4775 /* We must perform the conversion here so that we do not
4776 subsequently check to see whether BINFO is an accessible
4777 base. (It is OK for a constructor to call a constructor in
4778 an inaccessible base as long as the constructor being called
4780 if (!same_type_ignoring_top_level_qualifiers_p
4781 (TREE_TYPE (instance), BINFO_TYPE (binfo)))
4782 instance = convert_to_base_statically (instance, binfo);
4785 my_friendly_assert (instance != NULL_TREE, 20020712);
4787 /* Resolve the name. */
4788 if (!complete_type_or_else (BINFO_TYPE (binfo), NULL_TREE))
4789 return error_mark_node;
4791 fns = lookup_fnfields (binfo, name, 1);
4793 /* When making a call to a constructor or destructor for a subobject
4794 that uses virtual base classes, pass down a pointer to a VTT for
4796 if ((name == base_ctor_identifier
4797 || name == base_dtor_identifier)
4798 && TYPE_USES_VIRTUAL_BASECLASSES (class_type))
4803 /* If the current function is a complete object constructor
4804 or destructor, then we fetch the VTT directly.
4805 Otherwise, we look it up using the VTT we were given. */
4806 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
4807 vtt = decay_conversion (vtt);
4808 vtt = build (COND_EXPR, TREE_TYPE (vtt),
4809 build (EQ_EXPR, boolean_type_node,
4810 current_in_charge_parm, integer_zero_node),
4813 my_friendly_assert (BINFO_SUBVTT_INDEX (binfo), 20010110);
4814 sub_vtt = build (PLUS_EXPR, TREE_TYPE (vtt), vtt,
4815 BINFO_SUBVTT_INDEX (binfo));
4817 args = tree_cons (NULL_TREE, sub_vtt, args);
4820 return build_new_method_call (instance, fns, args,
4821 TYPE_BINFO (BINFO_TYPE (binfo)),
4825 /* Return the NAME, as a C string. The NAME indicates a function that
4826 is a member of TYPE. *FREE_P is set to true if the caller must
4827 free the memory returned.
4829 Rather than go through all of this, we should simply set the names
4830 of constructors and destructors appropriately, and dispense with
4831 ctor_identifier, dtor_identifier, etc. */
4834 name_as_c_string (tree name, tree type, bool *free_p)
4838 /* Assume that we will not allocate memory. */
4840 /* Constructors and destructors are special. */
4841 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
4844 = (char *) IDENTIFIER_POINTER (constructor_name (type));
4845 /* For a destructor, add the '~'. */
4846 if (name == complete_dtor_identifier
4847 || name == base_dtor_identifier
4848 || name == deleting_dtor_identifier)
4850 pretty_name = concat ("~", pretty_name, NULL);
4851 /* Remember that we need to free the memory allocated. */
4856 pretty_name = (char *) IDENTIFIER_POINTER (name);
4861 /* Build a call to "INSTANCE.FN (ARGS)". */
4864 build_new_method_call (tree instance, tree fns, tree args,
4865 tree conversion_path, int flags)
4867 struct z_candidate *candidates = 0, *cand;
4868 tree explicit_targs = NULL_TREE;
4869 tree basetype = NULL_TREE;
4872 tree mem_args = NULL_TREE, instance_ptr;
4878 int template_only = 0;
4884 my_friendly_assert (instance != NULL_TREE, 20020729);
4886 if (error_operand_p (instance)
4887 || error_operand_p (fns)
4888 || args == error_mark_node)
4889 return error_mark_node;
4891 orig_instance = instance;
4895 if (processing_template_decl)
4897 instance = build_non_dependent_expr (instance);
4898 if (!BASELINK_P (fns)
4899 && TREE_CODE (fns) != PSEUDO_DTOR_EXPR
4900 && TREE_TYPE (fns) != unknown_type_node)
4901 fns = build_non_dependent_expr (fns);
4902 args = build_non_dependent_args (orig_args);
4905 /* Process the argument list. */
4907 args = resolve_args (args);
4908 if (args == error_mark_node)
4909 return error_mark_node;
4911 if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
4912 instance = convert_from_reference (instance);
4913 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
4914 instance_ptr = build_this (instance);
4916 if (!BASELINK_P (fns))
4918 call = build_field_call (instance_ptr, fns, args);
4921 error ("call to non-function `%D'", fns);
4922 return error_mark_node;
4925 if (!conversion_path)
4926 conversion_path = BASELINK_BINFO (fns);
4927 access_binfo = BASELINK_ACCESS_BINFO (fns);
4928 optype = BASELINK_OPTYPE (fns);
4929 fns = BASELINK_FUNCTIONS (fns);
4931 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
4933 explicit_targs = TREE_OPERAND (fns, 1);
4934 fns = TREE_OPERAND (fns, 0);
4938 my_friendly_assert (TREE_CODE (fns) == FUNCTION_DECL
4939 || TREE_CODE (fns) == TEMPLATE_DECL
4940 || TREE_CODE (fns) == OVERLOAD,
4943 /* XXX this should be handled before we get here. */
4944 if (! IS_AGGR_TYPE (basetype))
4946 if ((flags & LOOKUP_COMPLAIN) && basetype != error_mark_node)
4947 error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
4948 fns, instance, basetype);
4950 return error_mark_node;
4953 fn = get_first_fn (fns);
4954 name = DECL_NAME (fn);
4956 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
4958 /* Callers should explicitly indicate whether they want to construct
4959 the complete object or just the part without virtual bases. */
4960 my_friendly_assert (name != ctor_identifier, 20000408);
4961 /* Similarly for destructors. */
4962 my_friendly_assert (name != dtor_identifier, 20000408);
4965 /* It's OK to call destructors on cv-qualified objects. Therefore,
4966 convert the INSTANCE_PTR to the unqualified type, if necessary. */
4967 if (DECL_DESTRUCTOR_P (fn))
4969 tree type = build_pointer_type (basetype);
4970 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
4971 instance_ptr = build_nop (type, instance_ptr);
4974 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
4975 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
4977 for (fn = fns; fn; fn = OVL_NEXT (fn))
4979 tree t = OVL_CURRENT (fn);
4982 /* We can end up here for copy-init of same or base class. */
4983 if ((flags & LOOKUP_ONLYCONVERTING)
4984 && DECL_NONCONVERTING_P (t))
4987 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
4988 this_arglist = mem_args;
4990 this_arglist = args;
4992 if (TREE_CODE (t) == TEMPLATE_DECL)
4993 /* A member template. */
4994 add_template_candidate (&candidates, t,
4997 this_arglist, optype,
5002 else if (! template_only)
5003 add_function_candidate (&candidates, t,
5011 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5014 /* XXX will LOOKUP_SPECULATIVELY be needed when this is done? */
5015 if (flags & LOOKUP_SPECULATIVELY)
5017 if (!COMPLETE_TYPE_P (basetype))
5018 cxx_incomplete_type_error (instance_ptr, basetype);
5024 pretty_name = name_as_c_string (name, basetype, &free_p);
5025 error ("no matching function for call to `%T::%s(%A)%#V'",
5026 basetype, pretty_name, user_args,
5027 TREE_TYPE (TREE_TYPE (instance_ptr)));
5031 print_z_candidates (candidates);
5032 return error_mark_node;
5035 cand = tourney (candidates);
5041 pretty_name = name_as_c_string (name, basetype, &free_p);
5042 error ("call of overloaded `%s(%A)' is ambiguous", pretty_name,
5044 print_z_candidates (candidates);
5047 return error_mark_node;
5050 if (DECL_PURE_VIRTUAL_P (cand->fn)
5051 && instance == current_class_ref
5052 && (DECL_CONSTRUCTOR_P (current_function_decl)
5053 || DECL_DESTRUCTOR_P (current_function_decl))
5054 && ! (flags & LOOKUP_NONVIRTUAL)
5055 && value_member (cand->fn, CLASSTYPE_PURE_VIRTUALS (basetype)))
5056 error ((DECL_CONSTRUCTOR_P (current_function_decl) ?
5057 "abstract virtual `%#D' called from constructor"
5058 : "abstract virtual `%#D' called from destructor"),
5060 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5061 && is_dummy_object (instance_ptr))
5063 error ("cannot call member function `%D' without object", cand->fn);
5064 return error_mark_node;
5067 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5068 && resolves_to_fixed_type_p (instance, 0))
5069 flags |= LOOKUP_NONVIRTUAL;
5071 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE)
5072 call = build_over_call (cand, flags);
5075 call = build_over_call (cand, flags);
5076 /* In an expression of the form `a->f()' where `f' turns out to
5077 be a static member function, `a' is none-the-less evaluated. */
5078 if (!is_dummy_object (instance_ptr) && TREE_SIDE_EFFECTS (instance))
5079 call = build (COMPOUND_EXPR, TREE_TYPE (call), instance, call);
5083 if (processing_template_decl && call != error_mark_node)
5084 return build_min_non_dep
5086 build_min_nt (COMPONENT_REF, orig_instance, orig_fns),
5091 /* Returns true iff standard conversion sequence ICS1 is a proper
5092 subsequence of ICS2. */
5095 is_subseq (tree ics1, tree ics2)
5097 /* We can assume that a conversion of the same code
5098 between the same types indicates a subsequence since we only get
5099 here if the types we are converting from are the same. */
5101 while (TREE_CODE (ics1) == RVALUE_CONV
5102 || TREE_CODE (ics1) == LVALUE_CONV)
5103 ics1 = TREE_OPERAND (ics1, 0);
5107 while (TREE_CODE (ics2) == RVALUE_CONV
5108 || TREE_CODE (ics2) == LVALUE_CONV)
5109 ics2 = TREE_OPERAND (ics2, 0);
5111 if (TREE_CODE (ics2) == USER_CONV
5112 || TREE_CODE (ics2) == AMBIG_CONV
5113 || TREE_CODE (ics2) == IDENTITY_CONV)
5114 /* At this point, ICS1 cannot be a proper subsequence of
5115 ICS2. We can get a USER_CONV when we are comparing the
5116 second standard conversion sequence of two user conversion
5120 ics2 = TREE_OPERAND (ics2, 0);
5122 if (TREE_CODE (ics2) == TREE_CODE (ics1)
5123 && same_type_p (TREE_TYPE (ics2), TREE_TYPE (ics1))
5124 && same_type_p (TREE_TYPE (TREE_OPERAND (ics2, 0)),
5125 TREE_TYPE (TREE_OPERAND (ics1, 0))))
5130 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5131 be any _TYPE nodes. */
5134 is_properly_derived_from (tree derived, tree base)
5136 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5137 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5140 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5141 considers every class derived from itself. */
5142 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5143 && DERIVED_FROM_P (base, derived));
5146 /* We build the ICS for an implicit object parameter as a pointer
5147 conversion sequence. However, such a sequence should be compared
5148 as if it were a reference conversion sequence. If ICS is the
5149 implicit conversion sequence for an implicit object parameter,
5150 modify it accordingly. */
5153 maybe_handle_implicit_object (tree *ics)
5155 if (ICS_THIS_FLAG (*ics))
5157 /* [over.match.funcs]
5159 For non-static member functions, the type of the
5160 implicit object parameter is "reference to cv X"
5161 where X is the class of which the function is a
5162 member and cv is the cv-qualification on the member
5163 function declaration. */
5165 tree reference_type;
5167 /* The `this' parameter is a pointer to a class type. Make the
5168 implicit conversion talk about a reference to that same class
5170 reference_type = TREE_TYPE (TREE_TYPE (*ics));
5171 reference_type = build_reference_type (reference_type);
5173 if (TREE_CODE (t) == QUAL_CONV)
5174 t = TREE_OPERAND (t, 0);
5175 if (TREE_CODE (t) == PTR_CONV)
5176 t = TREE_OPERAND (t, 0);
5177 t = build1 (IDENTITY_CONV, TREE_TYPE (TREE_TYPE (t)), NULL_TREE);
5178 t = direct_reference_binding (reference_type, t);
5183 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5184 and return the type to which the reference refers. Otherwise,
5185 leave *ICS unchanged and return NULL_TREE. */
5188 maybe_handle_ref_bind (tree *ics)
5190 if (TREE_CODE (*ics) == REF_BIND)
5192 tree old_ics = *ics;
5193 tree type = TREE_TYPE (TREE_TYPE (old_ics));
5194 *ics = TREE_OPERAND (old_ics, 0);
5195 ICS_USER_FLAG (*ics) = ICS_USER_FLAG (old_ics);
5196 ICS_BAD_FLAG (*ics) = ICS_BAD_FLAG (old_ics);
5203 /* Compare two implicit conversion sequences according to the rules set out in
5204 [over.ics.rank]. Return values:
5206 1: ics1 is better than ics2
5207 -1: ics2 is better than ics1
5208 0: ics1 and ics2 are indistinguishable */
5211 compare_ics (tree ics1, tree ics2)
5217 tree deref_from_type1 = NULL_TREE;
5218 tree deref_from_type2 = NULL_TREE;
5219 tree deref_to_type1 = NULL_TREE;
5220 tree deref_to_type2 = NULL_TREE;
5223 /* REF_BINDING is nonzero if the result of the conversion sequence
5224 is a reference type. In that case TARGET_TYPE is the
5225 type referred to by the reference. */
5229 /* Handle implicit object parameters. */
5230 maybe_handle_implicit_object (&ics1);
5231 maybe_handle_implicit_object (&ics2);
5233 /* Handle reference parameters. */
5234 target_type1 = maybe_handle_ref_bind (&ics1);
5235 target_type2 = maybe_handle_ref_bind (&ics2);
5239 When comparing the basic forms of implicit conversion sequences (as
5240 defined in _over.best.ics_)
5242 --a standard conversion sequence (_over.ics.scs_) is a better
5243 conversion sequence than a user-defined conversion sequence
5244 or an ellipsis conversion sequence, and
5246 --a user-defined conversion sequence (_over.ics.user_) is a
5247 better conversion sequence than an ellipsis conversion sequence
5248 (_over.ics.ellipsis_). */
5249 rank1 = ICS_RANK (ics1);
5250 rank2 = ICS_RANK (ics2);
5254 else if (rank1 < rank2)
5257 if (rank1 == BAD_RANK)
5259 /* XXX Isn't this an extension? */
5260 /* Both ICS are bad. We try to make a decision based on what
5261 would have happenned if they'd been good. */
5262 if (ICS_USER_FLAG (ics1) > ICS_USER_FLAG (ics2)
5263 || ICS_STD_RANK (ics1) > ICS_STD_RANK (ics2))
5265 else if (ICS_USER_FLAG (ics1) < ICS_USER_FLAG (ics2)
5266 || ICS_STD_RANK (ics1) < ICS_STD_RANK (ics2))
5269 /* We couldn't make up our minds; try to figure it out below. */
5272 if (ICS_ELLIPSIS_FLAG (ics1))
5273 /* Both conversions are ellipsis conversions. */
5276 /* User-defined conversion sequence U1 is a better conversion sequence
5277 than another user-defined conversion sequence U2 if they contain the
5278 same user-defined conversion operator or constructor and if the sec-
5279 ond standard conversion sequence of U1 is better than the second
5280 standard conversion sequence of U2. */
5282 if (ICS_USER_FLAG (ics1))
5286 for (t1 = ics1; TREE_CODE (t1) != USER_CONV; t1 = TREE_OPERAND (t1, 0))
5287 if (TREE_CODE (t1) == AMBIG_CONV)
5289 for (t2 = ics2; TREE_CODE (t2) != USER_CONV; t2 = TREE_OPERAND (t2, 0))
5290 if (TREE_CODE (t2) == AMBIG_CONV)
5293 if (USER_CONV_FN (t1) != USER_CONV_FN (t2))
5296 /* We can just fall through here, after setting up
5297 FROM_TYPE1 and FROM_TYPE2. */
5298 from_type1 = TREE_TYPE (t1);
5299 from_type2 = TREE_TYPE (t2);
5303 /* We're dealing with two standard conversion sequences.
5307 Standard conversion sequence S1 is a better conversion
5308 sequence than standard conversion sequence S2 if
5310 --S1 is a proper subsequence of S2 (comparing the conversion
5311 sequences in the canonical form defined by _over.ics.scs_,
5312 excluding any Lvalue Transformation; the identity
5313 conversion sequence is considered to be a subsequence of
5314 any non-identity conversion sequence */
5317 while (TREE_CODE (from_type1) != IDENTITY_CONV)
5318 from_type1 = TREE_OPERAND (from_type1, 0);
5319 from_type1 = TREE_TYPE (from_type1);
5322 while (TREE_CODE (from_type2) != IDENTITY_CONV)
5323 from_type2 = TREE_OPERAND (from_type2, 0);
5324 from_type2 = TREE_TYPE (from_type2);
5327 if (same_type_p (from_type1, from_type2))
5329 if (is_subseq (ics1, ics2))
5331 if (is_subseq (ics2, ics1))
5334 /* Otherwise, one sequence cannot be a subsequence of the other; they
5335 don't start with the same type. This can happen when comparing the
5336 second standard conversion sequence in two user-defined conversion
5343 --the rank of S1 is better than the rank of S2 (by the rules
5346 Standard conversion sequences are ordered by their ranks: an Exact
5347 Match is a better conversion than a Promotion, which is a better
5348 conversion than a Conversion.
5350 Two conversion sequences with the same rank are indistinguishable
5351 unless one of the following rules applies:
5353 --A conversion that is not a conversion of a pointer, or pointer
5354 to member, to bool is better than another conversion that is such
5357 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5358 so that we do not have to check it explicitly. */
5359 if (ICS_STD_RANK (ics1) < ICS_STD_RANK (ics2))
5361 else if (ICS_STD_RANK (ics2) < ICS_STD_RANK (ics1))
5364 to_type1 = TREE_TYPE (ics1);
5365 to_type2 = TREE_TYPE (ics2);
5367 if (TYPE_PTR_P (from_type1)
5368 && TYPE_PTR_P (from_type2)
5369 && TYPE_PTR_P (to_type1)
5370 && TYPE_PTR_P (to_type2))
5372 deref_from_type1 = TREE_TYPE (from_type1);
5373 deref_from_type2 = TREE_TYPE (from_type2);
5374 deref_to_type1 = TREE_TYPE (to_type1);
5375 deref_to_type2 = TREE_TYPE (to_type2);
5377 /* The rules for pointers to members A::* are just like the rules
5378 for pointers A*, except opposite: if B is derived from A then
5379 A::* converts to B::*, not vice versa. For that reason, we
5380 switch the from_ and to_ variables here. */
5381 else if ((TYPE_PTRMEM_P (from_type1) && TYPE_PTRMEM_P (from_type2)
5382 && TYPE_PTRMEM_P (to_type1) && TYPE_PTRMEM_P (to_type2))
5383 || (TYPE_PTRMEMFUNC_P (from_type1)
5384 && TYPE_PTRMEMFUNC_P (from_type2)
5385 && TYPE_PTRMEMFUNC_P (to_type1)
5386 && TYPE_PTRMEMFUNC_P (to_type2)))
5388 deref_to_type1 = TYPE_PTRMEM_CLASS_TYPE (from_type1);
5389 deref_to_type2 = TYPE_PTRMEM_CLASS_TYPE (from_type2);
5390 deref_from_type1 = TYPE_PTRMEM_CLASS_TYPE (to_type1);
5391 deref_from_type2 = TYPE_PTRMEM_CLASS_TYPE (to_type2);
5394 if (deref_from_type1 != NULL_TREE
5395 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5396 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5398 /* This was one of the pointer or pointer-like conversions.
5402 --If class B is derived directly or indirectly from class A,
5403 conversion of B* to A* is better than conversion of B* to
5404 void*, and conversion of A* to void* is better than
5405 conversion of B* to void*. */
5406 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5407 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5409 if (is_properly_derived_from (deref_from_type1,
5412 else if (is_properly_derived_from (deref_from_type2,
5416 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5417 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5419 if (same_type_p (deref_from_type1, deref_from_type2))
5421 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5423 if (is_properly_derived_from (deref_from_type1,
5427 /* We know that DEREF_TO_TYPE1 is `void' here. */
5428 else if (is_properly_derived_from (deref_from_type1,
5433 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5434 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5438 --If class B is derived directly or indirectly from class A
5439 and class C is derived directly or indirectly from B,
5441 --conversion of C* to B* is better than conversion of C* to
5444 --conversion of B* to A* is better than conversion of C* to
5446 if (same_type_p (deref_from_type1, deref_from_type2))
5448 if (is_properly_derived_from (deref_to_type1,
5451 else if (is_properly_derived_from (deref_to_type2,
5455 else if (same_type_p (deref_to_type1, deref_to_type2))
5457 if (is_properly_derived_from (deref_from_type2,
5460 else if (is_properly_derived_from (deref_from_type1,
5466 else if (CLASS_TYPE_P (non_reference (from_type1))
5467 && same_type_p (from_type1, from_type2))
5469 tree from = non_reference (from_type1);
5473 --binding of an expression of type C to a reference of type
5474 B& is better than binding an expression of type C to a
5475 reference of type A&
5477 --conversion of C to B is better than conversion of C to A, */
5478 if (is_properly_derived_from (from, to_type1)
5479 && is_properly_derived_from (from, to_type2))
5481 if (is_properly_derived_from (to_type1, to_type2))
5483 else if (is_properly_derived_from (to_type2, to_type1))
5487 else if (CLASS_TYPE_P (non_reference (to_type1))
5488 && same_type_p (to_type1, to_type2))
5490 tree to = non_reference (to_type1);
5494 --binding of an expression of type B to a reference of type
5495 A& is better than binding an expression of type C to a
5496 reference of type A&,
5498 --onversion of B to A is better than conversion of C to A */
5499 if (is_properly_derived_from (from_type1, to)
5500 && is_properly_derived_from (from_type2, to))
5502 if (is_properly_derived_from (from_type2, from_type1))
5504 else if (is_properly_derived_from (from_type1, from_type2))
5511 --S1 and S2 differ only in their qualification conversion and yield
5512 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5513 qualification signature of type T1 is a proper subset of the cv-
5514 qualification signature of type T2 */
5515 if (TREE_CODE (ics1) == QUAL_CONV
5516 && TREE_CODE (ics2) == QUAL_CONV
5517 && same_type_p (from_type1, from_type2))
5518 return comp_cv_qual_signature (to_type1, to_type2);
5522 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5523 types to which the references refer are the same type except for
5524 top-level cv-qualifiers, and the type to which the reference
5525 initialized by S2 refers is more cv-qualified than the type to
5526 which the reference initialized by S1 refers */
5528 if (target_type1 && target_type2
5529 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5530 return comp_cv_qualification (target_type2, target_type1);
5532 /* Neither conversion sequence is better than the other. */
5536 /* The source type for this standard conversion sequence. */
5539 source_type (tree t)
5541 for (;; t = TREE_OPERAND (t, 0))
5543 if (TREE_CODE (t) == USER_CONV
5544 || TREE_CODE (t) == AMBIG_CONV
5545 || TREE_CODE (t) == IDENTITY_CONV)
5546 return TREE_TYPE (t);
5551 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5552 a pointer to LOSER and re-running joust to produce the warning if WINNER
5553 is actually used. */
5556 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5558 winner->warnings = tree_cons (NULL_TREE,
5559 build_zc_wrapper (loser),
5563 /* Compare two candidates for overloading as described in
5564 [over.match.best]. Return values:
5566 1: cand1 is better than cand2
5567 -1: cand2 is better than cand1
5568 0: cand1 and cand2 are indistinguishable */
5571 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5574 int i, off1 = 0, off2 = 0, len;
5576 /* Candidates that involve bad conversions are always worse than those
5578 if (cand1->viable > cand2->viable)
5580 if (cand1->viable < cand2->viable)
5583 /* If we have two pseudo-candidates for conversions to the same type,
5584 or two candidates for the same function, arbitrarily pick one. */
5585 if (cand1->fn == cand2->fn
5586 && (TYPE_P (cand1->fn) || DECL_P (cand1->fn)))
5589 /* a viable function F1
5590 is defined to be a better function than another viable function F2 if
5591 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5592 ICSi(F2), and then */
5594 /* for some argument j, ICSj(F1) is a better conversion sequence than
5597 /* For comparing static and non-static member functions, we ignore
5598 the implicit object parameter of the non-static function. The
5599 standard says to pretend that the static function has an object
5600 parm, but that won't work with operator overloading. */
5601 len = TREE_VEC_LENGTH (cand1->convs);
5602 if (len != TREE_VEC_LENGTH (cand2->convs))
5604 if (DECL_STATIC_FUNCTION_P (cand1->fn)
5605 && ! DECL_STATIC_FUNCTION_P (cand2->fn))
5607 else if (! DECL_STATIC_FUNCTION_P (cand1->fn)
5608 && DECL_STATIC_FUNCTION_P (cand2->fn))
5617 for (i = 0; i < len; ++i)
5619 tree t1 = TREE_VEC_ELT (cand1->convs, i+off1);
5620 tree t2 = TREE_VEC_ELT (cand2->convs, i+off2);
5621 int comp = compare_ics (t1, t2);
5626 && ICS_RANK (t1) + ICS_RANK (t2) == STD_RANK + PROMO_RANK
5627 && TREE_CODE (t1) == STD_CONV
5628 && TREE_CODE (t2) == STD_CONV
5629 && TREE_CODE (TREE_TYPE (t1)) == INTEGER_TYPE
5630 && TREE_CODE (TREE_TYPE (t2)) == INTEGER_TYPE
5631 && (TYPE_PRECISION (TREE_TYPE (t1))
5632 == TYPE_PRECISION (TREE_TYPE (t2)))
5633 && (TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (t1, 0)))
5634 || (TREE_CODE (TREE_TYPE (TREE_OPERAND (t1, 0)))
5637 tree type = TREE_TYPE (TREE_OPERAND (t1, 0));
5639 struct z_candidate *w, *l;
5641 type1 = TREE_TYPE (t1), type2 = TREE_TYPE (t2),
5642 w = cand1, l = cand2;
5644 type1 = TREE_TYPE (t2), type2 = TREE_TYPE (t1),
5645 w = cand2, l = cand1;
5649 warning ("passing `%T' chooses `%T' over `%T'",
5650 type, type1, type2);
5651 warning (" in call to `%D'", w->fn);
5657 if (winner && comp != winner)
5666 /* warn about confusing overload resolution for user-defined conversions,
5667 either between a constructor and a conversion op, or between two
5669 if (winner && warn_conversion && cand1->second_conv
5670 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
5671 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
5673 struct z_candidate *w, *l;
5674 bool give_warning = false;
5677 w = cand1, l = cand2;
5679 w = cand2, l = cand1;
5681 /* We don't want to complain about `X::operator T1 ()'
5682 beating `X::operator T2 () const', when T2 is a no less
5683 cv-qualified version of T1. */
5684 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
5685 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
5687 tree t = TREE_TYPE (TREE_TYPE (l->fn));
5688 tree f = TREE_TYPE (TREE_TYPE (w->fn));
5690 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
5695 if (!comp_ptr_ttypes (t, f))
5696 give_warning = true;
5699 give_warning = true;
5705 tree source = source_type (TREE_VEC_ELT (w->convs, 0));
5706 if (! DECL_CONSTRUCTOR_P (w->fn))
5707 source = TREE_TYPE (source);
5708 warning ("choosing `%D' over `%D'", w->fn, l->fn);
5709 warning (" for conversion from `%T' to `%T'",
5710 source, TREE_TYPE (w->second_conv));
5711 warning (" because conversion sequence for the argument is better");
5721 F1 is a non-template function and F2 is a template function
5724 if (! cand1->template && cand2->template)
5726 else if (cand1->template && ! cand2->template)
5730 F1 and F2 are template functions and the function template for F1 is
5731 more specialized than the template for F2 according to the partial
5734 if (cand1->template && cand2->template)
5736 winner = more_specialized
5737 (TI_TEMPLATE (cand1->template), TI_TEMPLATE (cand2->template),
5739 /* Tell the deduction code how many real function arguments
5740 we saw, not counting the implicit 'this' argument. But,
5741 add_function_candidate() suppresses the "this" argument
5744 [temp.func.order]: The presence of unused ellipsis and default
5745 arguments has no effect on the partial ordering of function
5747 TREE_VEC_LENGTH (cand1->convs)
5748 - (DECL_NONSTATIC_MEMBER_FUNCTION_P (cand1->fn)
5749 - DECL_CONSTRUCTOR_P (cand1->fn)));
5755 the context is an initialization by user-defined conversion (see
5756 _dcl.init_ and _over.match.user_) and the standard conversion
5757 sequence from the return type of F1 to the destination type (i.e.,
5758 the type of the entity being initialized) is a better conversion
5759 sequence than the standard conversion sequence from the return type
5760 of F2 to the destination type. */
5762 if (cand1->second_conv)
5764 winner = compare_ics (cand1->second_conv, cand2->second_conv);
5769 /* Check whether we can discard a builtin candidate, either because we
5770 have two identical ones or matching builtin and non-builtin candidates.
5772 (Pedantically in the latter case the builtin which matched the user
5773 function should not be added to the overload set, but we spot it here.
5776 ... the builtin candidates include ...
5777 - do not have the same parameter type list as any non-template
5778 non-member candidate. */
5780 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
5781 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
5783 for (i = 0; i < len; ++i)
5784 if (!same_type_p (TREE_TYPE (TREE_VEC_ELT (cand1->convs, i)),
5785 TREE_TYPE (TREE_VEC_ELT (cand2->convs, i))))
5787 if (i == TREE_VEC_LENGTH (cand1->convs))
5789 if (cand1->fn == cand2->fn)
5790 /* Two built-in candidates; arbitrarily pick one. */
5792 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
5793 /* cand1 is built-in; prefer cand2. */
5796 /* cand2 is built-in; prefer cand1. */
5801 /* If the two functions are the same (this can happen with declarations
5802 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
5803 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
5804 && equal_functions (cand1->fn, cand2->fn))
5809 /* Extension: If the worst conversion for one candidate is worse than the
5810 worst conversion for the other, take the first. */
5813 int rank1 = IDENTITY_RANK, rank2 = IDENTITY_RANK;
5814 struct z_candidate *w = 0, *l = 0;
5816 for (i = 0; i < len; ++i)
5818 if (ICS_RANK (TREE_VEC_ELT (cand1->convs, i+off1)) > rank1)
5819 rank1 = ICS_RANK (TREE_VEC_ELT (cand1->convs, i+off1));
5820 if (ICS_RANK (TREE_VEC_ELT (cand2->convs, i+off2)) > rank2)
5821 rank2 = ICS_RANK (TREE_VEC_ELT (cand2->convs, i+off2));
5824 winner = 1, w = cand1, l = cand2;
5826 winner = -1, w = cand2, l = cand1;
5832 ISO C++ says that these are ambiguous, even \
5833 though the worst conversion for the first is better than \
5834 the worst conversion for the second:");
5835 print_z_candidate (_("candidate 1:"), w);
5836 print_z_candidate (_("candidate 2:"), l);
5844 my_friendly_assert (!winner, 20010121);
5848 /* Given a list of candidates for overloading, find the best one, if any.
5849 This algorithm has a worst case of O(2n) (winner is last), and a best
5850 case of O(n/2) (totally ambiguous); much better than a sorting
5853 static struct z_candidate *
5854 tourney (struct z_candidate *candidates)
5856 struct z_candidate *champ = candidates, *challenger;
5858 int champ_compared_to_predecessor = 0;
5860 /* Walk through the list once, comparing each current champ to the next
5861 candidate, knocking out a candidate or two with each comparison. */
5863 for (challenger = champ->next; challenger; )
5865 fate = joust (champ, challenger, 0);
5867 challenger = challenger->next;
5872 champ = challenger->next;
5875 champ_compared_to_predecessor = 0;
5880 champ_compared_to_predecessor = 1;
5883 challenger = champ->next;
5887 /* Make sure the champ is better than all the candidates it hasn't yet
5888 been compared to. */
5890 for (challenger = candidates;
5892 && !(champ_compared_to_predecessor && challenger->next == champ);
5893 challenger = challenger->next)
5895 fate = joust (champ, challenger, 0);
5903 /* Returns nonzero if things of type FROM can be converted to TO. */
5906 can_convert (tree to, tree from)
5908 return can_convert_arg (to, from, NULL_TREE);
5911 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
5914 can_convert_arg (tree to, tree from, tree arg)
5916 tree t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
5917 return (t && ! ICS_BAD_FLAG (t));
5920 /* Like can_convert_arg, but allows dubious conversions as well. */
5923 can_convert_arg_bad (tree to, tree from, tree arg)
5925 return implicit_conversion (to, from, arg, LOOKUP_NORMAL) != 0;
5928 /* Convert EXPR to TYPE. Return the converted expression.
5930 Note that we allow bad conversions here because by the time we get to
5931 this point we are committed to doing the conversion. If we end up
5932 doing a bad conversion, convert_like will complain. */
5935 perform_implicit_conversion (tree type, tree expr)
5939 if (error_operand_p (expr))
5940 return error_mark_node;
5941 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
5945 error ("could not convert `%E' to `%T'", expr, type);
5946 return error_mark_node;
5949 return convert_like (conv, expr);
5952 /* Convert EXPR to TYPE (as a direct-initialization) if that is
5953 permitted. If the conversion is valid, the converted expression is
5954 returned. Otherwise, NULL_TREE is returned. */
5957 perform_direct_initialization_if_possible (tree type, tree expr)
5961 if (type == error_mark_node || error_operand_p (expr))
5962 return error_mark_node;
5963 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
5965 if (!conv || ICS_BAD_FLAG (conv))
5967 return convert_like_real (conv, expr, NULL_TREE, 0, 0,
5968 /*issue_conversion_warnings=*/false);
5971 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
5972 is being bound to a temporary. Create and return a new VAR_DECL
5973 with the indicated TYPE; this variable will store the value to
5974 which the reference is bound. */
5977 make_temporary_var_for_ref_to_temp (tree decl, tree type)
5981 /* Create the variable. */
5982 var = build_decl (VAR_DECL, NULL_TREE, type);
5983 DECL_ARTIFICIAL (var) = 1;
5984 TREE_USED (var) = 1;
5986 /* Register the variable. */
5987 if (TREE_STATIC (decl))
5989 /* Namespace-scope or local static; give it a mangled name. */
5992 TREE_STATIC (var) = 1;
5993 name = mangle_ref_init_variable (decl);
5994 DECL_NAME (var) = name;
5995 SET_DECL_ASSEMBLER_NAME (var, name);
5996 var = pushdecl_top_level (var);
6000 /* Create a new cleanup level if necessary. */
6001 maybe_push_cleanup_level (type);
6002 /* Don't push unnamed temps. Do set DECL_CONTEXT, though. */
6003 DECL_CONTEXT (var) = current_function_decl;
6009 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6010 initializing a variable of that TYPE. If DECL is non-NULL, it is
6011 the VAR_DECL being initialized with the EXPR. (In that case, the
6012 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
6013 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
6014 return, if *CLEANUP is no longer NULL, it will be a CLEANUP_STMT
6015 that should be inserted after the returned expression is used to
6018 Return the converted expression. */
6021 initialize_reference (tree type, tree expr, tree decl, tree *cleanup)
6025 if (type == error_mark_node || error_operand_p (expr))
6026 return error_mark_node;
6028 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6029 if (!conv || ICS_BAD_FLAG (conv))
6031 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6032 && !real_lvalue_p (expr))
6033 error ("invalid initialization of non-const reference of "
6034 "type '%T' from a temporary of type '%T'",
6035 type, TREE_TYPE (expr));
6037 error ("could not convert `%E' to `%T'", expr, type);
6038 return error_mark_node;
6041 /* If DECL is non-NULL, then this special rule applies:
6045 The temporary to which the reference is bound or the temporary
6046 that is the complete object to which the reference is bound
6047 persists for the lifetime of the reference.
6049 The temporaries created during the evaluation of the expression
6050 initializing the reference, except the temporary to which the
6051 reference is bound, are destroyed at the end of the
6052 full-expression in which they are created.
6054 In that case, we store the converted expression into a new
6055 VAR_DECL in a new scope.
6057 However, we want to be careful not to create temporaries when
6058 they are not required. For example, given:
6061 struct D : public B {};
6065 there is no need to copy the return value from "f"; we can just
6066 extend its lifetime. Similarly, given:
6069 struct T { operator S(); };
6073 we can extend the lifetime of the return value of the conversion
6075 my_friendly_assert (TREE_CODE (conv) == REF_BIND, 20030302);
6079 tree base_conv_type;
6081 /* Skip over the REF_BIND. */
6082 conv = TREE_OPERAND (conv, 0);
6083 /* If the next conversion is a BASE_CONV, skip that too -- but
6084 remember that the conversion was required. */
6085 if (TREE_CODE (conv) == BASE_CONV && !NEED_TEMPORARY_P (conv))
6087 base_conv_type = TREE_TYPE (conv);
6088 conv = TREE_OPERAND (conv, 0);
6091 base_conv_type = NULL_TREE;
6092 /* Perform the remainder of the conversion. */
6093 expr = convert_like (conv, expr);
6094 if (!real_lvalue_p (expr))
6099 /* Create the temporary variable. */
6100 type = TREE_TYPE (expr);
6101 var = make_temporary_var_for_ref_to_temp (decl, type);
6102 layout_decl (var, 0);
6103 /* Create the INIT_EXPR that will initialize the temporary
6105 init = build (INIT_EXPR, type, var, expr);
6106 if (at_function_scope_p ())
6108 add_decl_stmt (var);
6109 *cleanup = cxx_maybe_build_cleanup (var);
6111 /* We must be careful to destroy the temporary only
6112 after its initialization has taken place. If the
6113 initialization throws an exception, then the
6114 destructor should not be run. We cannot simply
6115 transform INIT into something like:
6117 (INIT, ({ CLEANUP_STMT; }))
6119 because emit_local_var always treats the
6120 initializer as a full-expression. Thus, the
6121 destructor would run too early; it would run at the
6122 end of initializing the reference variable, rather
6123 than at the end of the block enclosing the
6126 The solution is to pass back a CLEANUP_STMT which
6127 the caller is responsible for attaching to the
6129 *cleanup = build_stmt (CLEANUP_STMT, var, *cleanup);
6133 rest_of_decl_compilation (var, NULL, /*toplev=*/1, at_eof);
6134 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6135 static_aggregates = tree_cons (NULL_TREE, var,
6138 /* Use its address to initialize the reference variable. */
6139 expr = build_address (var);
6140 expr = build (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6143 /* Take the address of EXPR. */
6144 expr = build_unary_op (ADDR_EXPR, expr, 0);
6145 /* If a BASE_CONV was required, perform it now. */
6147 expr = (perform_implicit_conversion
6148 (build_pointer_type (base_conv_type), expr));
6149 return build_nop (type, expr);
6152 /* Perform the conversion. */
6153 return convert_like (conv, expr);
6156 #include "gt-cp-call.h"