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"
41 static tree build_field_call (tree, tree, tree);
42 static struct z_candidate * tourney (struct z_candidate *);
43 static int equal_functions (tree, tree);
44 static int joust (struct z_candidate *, struct z_candidate *, bool);
45 static int compare_ics (tree, tree);
46 static tree build_over_call (struct z_candidate *, int);
47 static tree build_java_interface_fn_ref (tree, tree);
48 #define convert_like(CONV, EXPR) \
49 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
50 /*issue_conversion_warnings=*/true)
51 #define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
52 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
53 /*issue_conversion_warnings=*/true)
54 static tree convert_like_real (tree, tree, tree, int, int, bool);
55 static void op_error (enum tree_code, enum tree_code, tree, tree,
57 static tree build_object_call (tree, tree);
58 static tree resolve_args (tree);
59 static struct z_candidate *build_user_type_conversion_1 (tree, tree, int);
60 static void print_z_candidate (const char *, struct z_candidate *);
61 static void print_z_candidates (struct z_candidate *);
62 static tree build_this (tree);
63 static struct z_candidate *splice_viable (struct z_candidate *, bool, bool *);
64 static bool any_strictly_viable (struct z_candidate *);
65 static struct z_candidate *add_template_candidate
66 (struct z_candidate **, tree, tree, tree, tree, tree,
67 tree, tree, int, unification_kind_t);
68 static struct z_candidate *add_template_candidate_real
69 (struct z_candidate **, tree, tree, tree, tree, tree,
70 tree, tree, int, tree, unification_kind_t);
71 static struct z_candidate *add_template_conv_candidate
72 (struct z_candidate **, tree, tree, tree, tree, tree, tree);
73 static void add_builtin_candidates
74 (struct z_candidate **, enum tree_code, enum tree_code,
76 static void add_builtin_candidate
77 (struct z_candidate **, enum tree_code, enum tree_code,
78 tree, tree, tree, tree *, tree *, int);
79 static bool is_complete (tree);
80 static void build_builtin_candidate
81 (struct z_candidate **, tree, tree, tree, tree *, tree *,
83 static struct z_candidate *add_conv_candidate
84 (struct z_candidate **, tree, tree, tree, tree, tree);
85 static struct z_candidate *add_function_candidate
86 (struct z_candidate **, tree, tree, tree, tree, tree, int);
87 static tree implicit_conversion (tree, tree, tree, int);
88 static tree standard_conversion (tree, tree, tree);
89 static tree reference_binding (tree, tree, tree, int);
90 static tree build_conv (enum tree_code, tree, tree);
91 static bool is_subseq (tree, tree);
92 static tree maybe_handle_ref_bind (tree *);
93 static void maybe_handle_implicit_object (tree *);
94 static struct z_candidate *add_candidate
95 (struct z_candidate **, tree, tree, tree, tree, tree, int);
96 static tree source_type (tree);
97 static void add_warning (struct z_candidate *, struct z_candidate *);
98 static bool reference_related_p (tree, tree);
99 static bool reference_compatible_p (tree, tree);
100 static tree convert_class_to_reference (tree, tree, tree);
101 static tree direct_reference_binding (tree, tree);
102 static bool promoted_arithmetic_type_p (tree);
103 static tree conditional_conversion (tree, tree);
104 static char *name_as_c_string (tree, tree, bool *);
105 static tree call_builtin_trap (void);
106 static tree prep_operand (tree);
107 static void add_candidates (tree, tree, tree, bool, tree, tree,
108 int, struct z_candidate **);
109 static tree merge_conversion_sequences (tree, tree);
112 build_vfield_ref (tree datum, tree type)
114 if (datum == error_mark_node)
115 return error_mark_node;
117 if (TREE_CODE (TREE_TYPE (datum)) == REFERENCE_TYPE)
118 datum = convert_from_reference (datum);
120 if (TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
121 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
122 datum = convert_to_base (datum, type, /*check_access=*/false);
124 return build (COMPONENT_REF, TREE_TYPE (TYPE_VFIELD (type)),
125 datum, TYPE_VFIELD (type));
128 /* Build a call to a member of an object. I.e., one that overloads
129 operator ()(), or is a pointer-to-function or pointer-to-method. */
132 build_field_call (tree instance_ptr, tree decl, tree parms)
136 if (decl == error_mark_node || decl == NULL_TREE)
139 if (TREE_CODE (decl) == FIELD_DECL || TREE_CODE (decl) == VAR_DECL)
141 /* If it's a field, try overloading operator (),
142 or calling if the field is a pointer-to-function. */
143 instance = build_indirect_ref (instance_ptr, NULL);
144 instance = build_class_member_access_expr (instance, decl,
145 /*access_path=*/NULL_TREE,
146 /*preserve_reference=*/false);
148 if (instance == error_mark_node)
149 return error_mark_node;
151 if (IS_AGGR_TYPE (TREE_TYPE (instance)))
152 return build_new_op (CALL_EXPR, LOOKUP_NORMAL,
153 instance, parms, NULL_TREE);
154 else if (TREE_CODE (TREE_TYPE (instance)) == FUNCTION_TYPE
155 || (TREE_CODE (TREE_TYPE (instance)) == POINTER_TYPE
156 && (TREE_CODE (TREE_TYPE (TREE_TYPE (instance)))
158 return build_function_call (instance, parms);
164 /* Returns nonzero iff the destructor name specified in NAME
165 (a BIT_NOT_EXPR) matches BASETYPE. The operand of NAME can take many
169 check_dtor_name (tree basetype, tree name)
171 name = TREE_OPERAND (name, 0);
173 /* Just accept something we've already complained about. */
174 if (name == error_mark_node)
177 if (TREE_CODE (name) == TYPE_DECL)
178 name = TREE_TYPE (name);
179 else if (TYPE_P (name))
181 else if (TREE_CODE (name) == IDENTIFIER_NODE)
183 if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
184 || (TREE_CODE (basetype) == ENUMERAL_TYPE
185 && name == TYPE_IDENTIFIER (basetype)))
188 name = get_type_value (name);
192 template <class T> struct S { ~S(); };
196 NAME will be a class template. */
197 else if (DECL_CLASS_TEMPLATE_P (name))
202 if (name && TYPE_MAIN_VARIANT (basetype) == TYPE_MAIN_VARIANT (name))
207 /* We want the address of a function or method. We avoid creating a
208 pointer-to-member function. */
211 build_addr_func (tree function)
213 tree type = TREE_TYPE (function);
215 /* We have to do these by hand to avoid real pointer to member
217 if (TREE_CODE (type) == METHOD_TYPE)
219 if (TREE_CODE (function) == OFFSET_REF)
221 tree object = build_address (TREE_OPERAND (function, 0));
222 return get_member_function_from_ptrfunc (&object,
223 TREE_OPERAND (function, 1));
225 function = build_address (function);
228 function = decay_conversion (function);
233 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
234 POINTER_TYPE to those. Note, pointer to member function types
235 (TYPE_PTRMEMFUNC_P) must be handled by our callers. */
238 build_call (tree function, tree parms)
240 int is_constructor = 0;
247 function = build_addr_func (function);
249 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
251 sorry ("unable to call pointer to member function here");
252 return error_mark_node;
255 fntype = TREE_TYPE (TREE_TYPE (function));
256 result_type = TREE_TYPE (fntype);
258 if (TREE_CODE (function) == ADDR_EXPR
259 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
260 decl = TREE_OPERAND (function, 0);
264 /* We check both the decl and the type; a function may be known not to
265 throw without being declared throw(). */
266 nothrow = ((decl && TREE_NOTHROW (decl))
267 || TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
269 if (decl && TREE_THIS_VOLATILE (decl) && cfun)
270 current_function_returns_abnormally = 1;
272 if (decl && TREE_DEPRECATED (decl))
273 warn_deprecated_use (decl);
274 require_complete_eh_spec_types (fntype, decl);
276 if (decl && DECL_CONSTRUCTOR_P (decl))
279 if (decl && ! TREE_USED (decl))
281 /* We invoke build_call directly for several library functions.
282 These may have been declared normally if we're building libgcc,
283 so we can't just check DECL_ARTIFICIAL. */
284 if (DECL_ARTIFICIAL (decl)
285 || !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), "__", 2))
291 /* Don't pass empty class objects by value. This is useful
292 for tags in STL, which are used to control overload resolution.
293 We don't need to handle other cases of copying empty classes. */
294 if (! decl || ! DECL_BUILT_IN (decl))
295 for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
296 if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
297 && ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
299 tree t = build (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
300 TREE_VALUE (tmp) = build (COMPOUND_EXPR, TREE_TYPE (t),
301 TREE_VALUE (tmp), t);
304 function = build_nt (CALL_EXPR, function, parms, NULL_TREE);
305 TREE_HAS_CONSTRUCTOR (function) = is_constructor;
306 TREE_TYPE (function) = result_type;
307 TREE_SIDE_EFFECTS (function) = 1;
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 TYPE_MAIN_VARIANT (t);
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_PTRMEMFUNC_P (to))
646 && expr && null_ptr_cst_p (expr))
648 conv = build_conv (STD_CONV, to, conv);
650 else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
651 || (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
653 /* For backwards brain damage compatibility, allow interconversion of
654 pointers and integers with a pedwarn. */
655 conv = build_conv (STD_CONV, to, conv);
656 ICS_BAD_FLAG (conv) = 1;
658 else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE
659 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
661 /* For backwards brain damage compatibility, allow interconversion of
662 enums and integers with a pedwarn. */
663 conv = build_conv (STD_CONV, to, conv);
664 ICS_BAD_FLAG (conv) = 1;
666 else if (tcode == POINTER_TYPE && fcode == POINTER_TYPE)
668 enum tree_code ufcode = TREE_CODE (TREE_TYPE (from));
669 enum tree_code utcode = TREE_CODE (TREE_TYPE (to));
671 if (same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
674 else if (utcode == VOID_TYPE && ufcode != OFFSET_TYPE
675 && ufcode != FUNCTION_TYPE)
677 from = build_pointer_type
678 (cp_build_qualified_type (void_type_node,
679 cp_type_quals (TREE_TYPE (from))));
680 conv = build_conv (PTR_CONV, from, conv);
682 else if (ufcode == OFFSET_TYPE && utcode == OFFSET_TYPE)
684 tree fbase = TYPE_OFFSET_BASETYPE (TREE_TYPE (from));
685 tree tbase = TYPE_OFFSET_BASETYPE (TREE_TYPE (to));
687 if (DERIVED_FROM_P (fbase, tbase)
688 && (same_type_ignoring_top_level_qualifiers_p
689 (TREE_TYPE (TREE_TYPE (from)),
690 TREE_TYPE (TREE_TYPE (to)))))
692 from = build_ptrmem_type (tbase, TREE_TYPE (TREE_TYPE (from)));
693 conv = build_conv (PMEM_CONV, from, conv);
696 else if (IS_AGGR_TYPE (TREE_TYPE (from))
697 && IS_AGGR_TYPE (TREE_TYPE (to)))
699 if (DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
702 cp_build_qualified_type (TREE_TYPE (to),
703 cp_type_quals (TREE_TYPE (from)));
704 from = build_pointer_type (from);
705 conv = build_conv (PTR_CONV, from, conv);
709 if (same_type_p (from, to))
711 else if (comp_ptr_ttypes (TREE_TYPE (to), TREE_TYPE (from)))
712 conv = build_conv (QUAL_CONV, to, conv);
713 else if (expr && string_conv_p (to, expr, 0))
714 /* converting from string constant to char *. */
715 conv = build_conv (QUAL_CONV, to, conv);
716 else if (ptr_reasonably_similar (TREE_TYPE (to), TREE_TYPE (from)))
718 conv = build_conv (PTR_CONV, to, conv);
719 ICS_BAD_FLAG (conv) = 1;
726 else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
728 tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
729 tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
730 tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
731 tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
733 if (!DERIVED_FROM_P (fbase, tbase)
734 || !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
735 || !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
736 TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
737 || cp_type_quals (fbase) != cp_type_quals (tbase))
740 from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
741 from = build_cplus_method_type (from, TREE_TYPE (fromfn),
742 TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
743 from = build_ptrmemfunc_type (build_pointer_type (from));
744 conv = build_conv (PMEM_CONV, from, conv);
746 else if (tcode == BOOLEAN_TYPE)
748 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE
749 || fcode == POINTER_TYPE || TYPE_PTRMEMFUNC_P (from)))
752 conv = build_conv (STD_CONV, to, conv);
753 if (fcode == POINTER_TYPE
754 || (TYPE_PTRMEMFUNC_P (from) && ICS_STD_RANK (conv) < PBOOL_RANK))
755 ICS_STD_RANK (conv) = PBOOL_RANK;
757 /* We don't check for ENUMERAL_TYPE here because there are no standard
758 conversions to enum type. */
759 else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
760 || tcode == REAL_TYPE)
762 if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
764 conv = build_conv (STD_CONV, to, conv);
766 /* Give this a better rank if it's a promotion. */
767 if (to == type_promotes_to (from)
768 && ICS_STD_RANK (TREE_OPERAND (conv, 0)) <= PROMO_RANK)
769 ICS_STD_RANK (conv) = PROMO_RANK;
771 else if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
772 && is_properly_derived_from (from, to))
774 if (TREE_CODE (conv) == RVALUE_CONV)
775 conv = TREE_OPERAND (conv, 0);
776 conv = build_conv (BASE_CONV, to, conv);
777 /* The derived-to-base conversion indicates the initialization
778 of a parameter with base type from an object of a derived
779 type. A temporary object is created to hold the result of
781 NEED_TEMPORARY_P (conv) = 1;
789 /* Returns nonzero if T1 is reference-related to T2. */
792 reference_related_p (tree t1, tree t2)
794 t1 = TYPE_MAIN_VARIANT (t1);
795 t2 = TYPE_MAIN_VARIANT (t2);
799 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
800 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
802 return (same_type_p (t1, t2)
803 || (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
804 && DERIVED_FROM_P (t1, t2)));
807 /* Returns nonzero if T1 is reference-compatible with T2. */
810 reference_compatible_p (tree t1, tree t2)
814 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
815 reference-related to T2 and cv1 is the same cv-qualification as,
816 or greater cv-qualification than, cv2. */
817 return (reference_related_p (t1, t2)
818 && at_least_as_qualified_p (t1, t2));
821 /* Determine whether or not the EXPR (of class type S) can be
822 converted to T as in [over.match.ref]. */
825 convert_class_to_reference (tree t, tree s, tree expr)
831 struct z_candidate *candidates;
832 struct z_candidate *cand;
835 conversions = lookup_conversions (s);
841 Assuming that "cv1 T" is the underlying type of the reference
842 being initialized, and "cv S" is the type of the initializer
843 expression, with S a class type, the candidate functions are
846 --The conversion functions of S and its base classes are
847 considered. Those that are not hidden within S and yield type
848 "reference to cv2 T2", where "cv1 T" is reference-compatible
849 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
851 The argument list has one argument, which is the initializer
856 /* Conceptually, we should take the address of EXPR and put it in
857 the argument list. Unfortunately, however, that can result in
858 error messages, which we should not issue now because we are just
859 trying to find a conversion operator. Therefore, we use NULL,
860 cast to the appropriate type. */
861 arglist = build_int_2 (0, 0);
862 TREE_TYPE (arglist) = build_pointer_type (s);
863 arglist = build_tree_list (NULL_TREE, arglist);
865 reference_type = build_reference_type (t);
869 tree fns = TREE_VALUE (conversions);
871 for (; fns; fns = OVL_NEXT (fns))
873 tree f = OVL_CURRENT (fns);
874 tree t2 = TREE_TYPE (TREE_TYPE (f));
878 /* If this is a template function, try to get an exact
880 if (TREE_CODE (f) == TEMPLATE_DECL)
882 cand = add_template_candidate (&candidates,
888 TREE_PURPOSE (conversions),
894 /* Now, see if the conversion function really returns
895 an lvalue of the appropriate type. From the
896 point of view of unification, simply returning an
897 rvalue of the right type is good enough. */
899 t2 = TREE_TYPE (TREE_TYPE (f));
900 if (TREE_CODE (t2) != REFERENCE_TYPE
901 || !reference_compatible_p (t, TREE_TYPE (t2)))
903 candidates = candidates->next;
908 else if (TREE_CODE (t2) == REFERENCE_TYPE
909 && reference_compatible_p (t, TREE_TYPE (t2)))
910 cand = add_function_candidate (&candidates, f, s, arglist,
912 TREE_PURPOSE (conversions),
916 /* Build a standard conversion sequence indicating the
917 binding from the reference type returned by the
918 function to the desired REFERENCE_TYPE. */
920 = (direct_reference_binding
922 build1 (IDENTITY_CONV,
923 TREE_TYPE (TREE_TYPE (TREE_TYPE (cand->fn))),
926 conversions = TREE_CHAIN (conversions);
929 candidates = splice_viable (candidates, pedantic, &any_viable_p);
930 /* If none of the conversion functions worked out, let our caller
935 cand = tourney (candidates);
939 /* Now that we know that this is the function we're going to use fix
940 the dummy first argument. */
941 cand->args = tree_cons (NULL_TREE,
943 TREE_CHAIN (cand->args));
945 /* Build a user-defined conversion sequence representing the
947 conv = build_conv (USER_CONV,
948 TREE_TYPE (TREE_TYPE (cand->fn)),
949 build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
950 TREE_OPERAND (conv, 1) = build_zc_wrapper (cand);
952 /* Merge it with the standard conversion sequence from the
953 conversion function's return type to the desired type. */
954 cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
956 if (cand->viable == -1)
957 ICS_BAD_FLAG (conv) = 1;
959 return cand->second_conv;
962 /* A reference of the indicated TYPE is being bound directly to the
963 expression represented by the implicit conversion sequence CONV.
964 Return a conversion sequence for this binding. */
967 direct_reference_binding (tree type, tree conv)
971 my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 20030306);
972 my_friendly_assert (TREE_CODE (TREE_TYPE (conv)) != REFERENCE_TYPE,
975 t = TREE_TYPE (type);
979 When a parameter of reference type binds directly
980 (_dcl.init.ref_) to an argument expression, the implicit
981 conversion sequence is the identity conversion, unless the
982 argument expression has a type that is a derived class of the
983 parameter type, in which case the implicit conversion sequence is
984 a derived-to-base Conversion.
986 If the parameter binds directly to the result of applying a
987 conversion function to the argument expression, the implicit
988 conversion sequence is a user-defined conversion sequence
989 (_over.ics.user_), with the second standard conversion sequence
990 either an identity conversion or, if the conversion function
991 returns an entity of a type that is a derived class of the
992 parameter type, a derived-to-base conversion. */
993 if (!same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (conv)))
995 /* Represent the derived-to-base conversion. */
996 conv = build_conv (BASE_CONV, t, conv);
997 /* We will actually be binding to the base-class subobject in
998 the derived class, so we mark this conversion appropriately.
999 That way, convert_like knows not to generate a temporary. */
1000 NEED_TEMPORARY_P (conv) = 0;
1002 return build_conv (REF_BIND, type, conv);
1005 /* Returns the conversion path from type FROM to reference type TO for
1006 purposes of reference binding. For lvalue binding, either pass a
1007 reference type to FROM or an lvalue expression to EXPR. If the
1008 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1009 the conversion returned. */
1012 reference_binding (tree rto, tree rfrom, tree expr, int flags)
1014 tree conv = NULL_TREE;
1015 tree to = TREE_TYPE (rto);
1019 cp_lvalue_kind lvalue_p = clk_none;
1021 if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
1023 expr = instantiate_type (to, expr, tf_none);
1024 if (expr == error_mark_node)
1026 from = TREE_TYPE (expr);
1029 if (TREE_CODE (from) == REFERENCE_TYPE)
1031 /* Anything with reference type is an lvalue. */
1032 lvalue_p = clk_ordinary;
1033 from = TREE_TYPE (from);
1036 lvalue_p = real_lvalue_p (expr);
1038 /* Figure out whether or not the types are reference-related and
1039 reference compatible. We have do do this after stripping
1040 references from FROM. */
1041 related_p = reference_related_p (to, from);
1042 compatible_p = reference_compatible_p (to, from);
1044 if (lvalue_p && compatible_p)
1048 If the initializer expression
1050 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1051 is reference-compatible with "cv2 T2,"
1053 the reference is bound directly to the initializer expression
1055 conv = build1 (IDENTITY_CONV, from, expr);
1056 conv = direct_reference_binding (rto, conv);
1057 if ((lvalue_p & clk_bitfield) != 0
1058 && CP_TYPE_CONST_NON_VOLATILE_P (to))
1059 /* For the purposes of overload resolution, we ignore the fact
1060 this expression is a bitfield. (In particular,
1061 [over.ics.ref] says specifically that a function with a
1062 non-const reference parameter is viable even if the
1063 argument is a bitfield.)
1065 However, when we actually call the function we must create
1066 a temporary to which to bind the reference. If the
1067 reference is volatile, or isn't const, then we cannot make
1068 a temporary, so we just issue an error when the conversion
1070 NEED_TEMPORARY_P (conv) = 1;
1073 else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
1077 If the initializer expression
1079 -- has a class type (i.e., T2 is a class type) can be
1080 implicitly converted to an lvalue of type "cv3 T3," where
1081 "cv1 T1" is reference-compatible with "cv3 T3". (this
1082 conversion is selected by enumerating the applicable
1083 conversion functions (_over.match.ref_) and choosing the
1084 best one through overload resolution. (_over.match_).
1086 the reference is bound to the lvalue result of the conversion
1087 in the second case. */
1088 conv = convert_class_to_reference (to, from, expr);
1093 /* From this point on, we conceptually need temporaries, even if we
1094 elide them. Only the cases above are "direct bindings". */
1095 if (flags & LOOKUP_NO_TEMP_BIND)
1100 When a parameter of reference type is not bound directly to an
1101 argument expression, the conversion sequence is the one required
1102 to convert the argument expression to the underlying type of the
1103 reference according to _over.best.ics_. Conceptually, this
1104 conversion sequence corresponds to copy-initializing a temporary
1105 of the underlying type with the argument expression. Any
1106 difference in top-level cv-qualification is subsumed by the
1107 initialization itself and does not constitute a conversion. */
1111 Otherwise, the reference shall be to a non-volatile const type. */
1112 if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
1117 If the initializer expression is an rvalue, with T2 a class type,
1118 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1119 is bound in one of the following ways:
1121 -- The reference is bound to the object represented by the rvalue
1122 or to a sub-object within that object.
1126 We use the first alternative. The implicit conversion sequence
1127 is supposed to be same as we would obtain by generating a
1128 temporary. Fortunately, if the types are reference compatible,
1129 then this is either an identity conversion or the derived-to-base
1130 conversion, just as for direct binding. */
1131 if (CLASS_TYPE_P (from) && compatible_p)
1133 conv = build1 (IDENTITY_CONV, from, expr);
1134 return direct_reference_binding (rto, conv);
1139 Otherwise, a temporary of type "cv1 T1" is created and
1140 initialized from the initializer expression using the rules for a
1141 non-reference copy initialization. If T1 is reference-related to
1142 T2, cv1 must be the same cv-qualification as, or greater
1143 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1144 if (related_p && !at_least_as_qualified_p (to, from))
1147 conv = implicit_conversion (to, from, expr, flags);
1151 conv = build_conv (REF_BIND, rto, conv);
1152 /* This reference binding, unlike those above, requires the
1153 creation of a temporary. */
1154 NEED_TEMPORARY_P (conv) = 1;
1159 /* Returns the implicit conversion sequence (see [over.ics]) from type FROM
1160 to type TO. The optional expression EXPR may affect the conversion.
1161 FLAGS are the usual overloading flags. Only LOOKUP_NO_CONVERSION is
1165 implicit_conversion (tree to, tree from, tree expr, int flags)
1169 if (from == error_mark_node || to == error_mark_node
1170 || expr == error_mark_node)
1173 if (TREE_CODE (to) == REFERENCE_TYPE)
1174 conv = reference_binding (to, from, expr, flags);
1176 conv = standard_conversion (to, from, expr);
1181 if (expr != NULL_TREE
1182 && (IS_AGGR_TYPE (from)
1183 || IS_AGGR_TYPE (to))
1184 && (flags & LOOKUP_NO_CONVERSION) == 0)
1186 struct z_candidate *cand;
1188 cand = build_user_type_conversion_1
1189 (to, expr, LOOKUP_ONLYCONVERTING);
1191 conv = cand->second_conv;
1193 /* We used to try to bind a reference to a temporary here, but that
1194 is now handled by the recursive call to this function at the end
1195 of reference_binding. */
1202 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1205 static struct z_candidate *
1206 add_candidate (struct z_candidate **candidates,
1207 tree fn, tree args, tree convs, tree access_path,
1208 tree conversion_path, int viable)
1210 struct z_candidate *cand
1211 = (struct z_candidate *) ggc_alloc_cleared (sizeof (struct z_candidate));
1215 cand->convs = convs;
1216 cand->access_path = access_path;
1217 cand->conversion_path = conversion_path;
1218 cand->viable = viable;
1219 cand->next = *candidates;
1225 /* Create an overload candidate for the function or method FN called with
1226 the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
1227 to implicit_conversion.
1229 CTYPE, if non-NULL, is the type we want to pretend this function
1230 comes from for purposes of overload resolution. */
1232 static struct z_candidate *
1233 add_function_candidate (struct z_candidate **candidates,
1234 tree fn, tree ctype, tree arglist,
1235 tree access_path, tree conversion_path,
1238 tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
1241 tree parmnode, argnode;
1245 /* Built-in functions that haven't been declared don't really
1247 if (DECL_ANTICIPATED (fn))
1250 /* The `this', `in_chrg' and VTT arguments to constructors are not
1251 considered in overload resolution. */
1252 if (DECL_CONSTRUCTOR_P (fn))
1254 parmlist = skip_artificial_parms_for (fn, parmlist);
1255 orig_arglist = arglist;
1256 arglist = skip_artificial_parms_for (fn, arglist);
1259 orig_arglist = arglist;
1261 len = list_length (arglist);
1262 convs = make_tree_vec (len);
1264 /* 13.3.2 - Viable functions [over.match.viable]
1265 First, to be a viable function, a candidate function shall have enough
1266 parameters to agree in number with the arguments in the list.
1268 We need to check this first; otherwise, checking the ICSes might cause
1269 us to produce an ill-formed template instantiation. */
1271 parmnode = parmlist;
1272 for (i = 0; i < len; ++i)
1274 if (parmnode == NULL_TREE || parmnode == void_list_node)
1276 parmnode = TREE_CHAIN (parmnode);
1279 if (i < len && parmnode)
1282 /* Make sure there are default args for the rest of the parms. */
1283 else if (!sufficient_parms_p (parmnode))
1289 /* Second, for F to be a viable function, there shall exist for each
1290 argument an implicit conversion sequence that converts that argument
1291 to the corresponding parameter of F. */
1293 parmnode = parmlist;
1296 for (i = 0; i < len; ++i)
1298 tree arg = TREE_VALUE (argnode);
1299 tree argtype = lvalue_type (arg);
1303 if (parmnode == void_list_node)
1306 is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1307 && ! DECL_CONSTRUCTOR_P (fn));
1311 tree parmtype = TREE_VALUE (parmnode);
1313 /* The type of the implicit object parameter ('this') for
1314 overload resolution is not always the same as for the
1315 function itself; conversion functions are considered to
1316 be members of the class being converted, and functions
1317 introduced by a using-declaration are considered to be
1318 members of the class that uses them.
1320 Since build_over_call ignores the ICS for the `this'
1321 parameter, we can just change the parm type. */
1322 if (ctype && is_this)
1325 = build_qualified_type (ctype,
1326 TYPE_QUALS (TREE_TYPE (parmtype)));
1327 parmtype = build_pointer_type (parmtype);
1330 t = implicit_conversion (parmtype, argtype, arg, flags);
1334 t = build1 (IDENTITY_CONV, argtype, arg);
1335 ICS_ELLIPSIS_FLAG (t) = 1;
1339 ICS_THIS_FLAG (t) = 1;
1341 TREE_VEC_ELT (convs, i) = t;
1348 if (ICS_BAD_FLAG (t))
1352 parmnode = TREE_CHAIN (parmnode);
1353 argnode = TREE_CHAIN (argnode);
1357 return add_candidate (candidates, fn, orig_arglist, convs, access_path,
1358 conversion_path, viable);
1361 /* Create an overload candidate for the conversion function FN which will
1362 be invoked for expression OBJ, producing a pointer-to-function which
1363 will in turn be called with the argument list ARGLIST, and add it to
1364 CANDIDATES. FLAGS is passed on to implicit_conversion.
1366 Actually, we don't really care about FN; we care about the type it
1367 converts to. There may be multiple conversion functions that will
1368 convert to that type, and we rely on build_user_type_conversion_1 to
1369 choose the best one; so when we create our candidate, we record the type
1370 instead of the function. */
1372 static struct z_candidate *
1373 add_conv_candidate (struct z_candidate **candidates, tree fn, tree obj,
1374 tree arglist, tree access_path, tree conversion_path)
1376 tree totype = TREE_TYPE (TREE_TYPE (fn));
1377 int i, len, viable, flags;
1378 tree parmlist, convs, parmnode, argnode;
1380 for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
1381 parmlist = TREE_TYPE (parmlist);
1382 parmlist = TYPE_ARG_TYPES (parmlist);
1384 len = list_length (arglist) + 1;
1385 convs = make_tree_vec (len);
1386 parmnode = parmlist;
1389 flags = LOOKUP_NORMAL;
1391 /* Don't bother looking up the same type twice. */
1392 if (*candidates && (*candidates)->fn == totype)
1395 for (i = 0; i < len; ++i)
1397 tree arg = i == 0 ? obj : TREE_VALUE (argnode);
1398 tree argtype = lvalue_type (arg);
1402 t = implicit_conversion (totype, argtype, arg, flags);
1403 else if (parmnode == void_list_node)
1406 t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, flags);
1409 t = build1 (IDENTITY_CONV, argtype, arg);
1410 ICS_ELLIPSIS_FLAG (t) = 1;
1413 TREE_VEC_ELT (convs, i) = t;
1417 if (ICS_BAD_FLAG (t))
1424 parmnode = TREE_CHAIN (parmnode);
1425 argnode = TREE_CHAIN (argnode);
1431 if (!sufficient_parms_p (parmnode))
1434 return add_candidate (candidates, totype, arglist, convs, access_path,
1435 conversion_path, viable);
1439 build_builtin_candidate (struct z_candidate **candidates, tree fnname,
1440 tree type1, tree type2, tree *args, tree *argtypes,
1450 convs = make_tree_vec (args[2] ? 3 : (args[1] ? 2 : 1));
1452 for (i = 0; i < 2; ++i)
1457 t = implicit_conversion (types[i], argtypes[i], args[i], flags);
1461 /* We need something for printing the candidate. */
1462 t = build1 (IDENTITY_CONV, types[i], NULL_TREE);
1464 else if (ICS_BAD_FLAG (t))
1466 TREE_VEC_ELT (convs, i) = t;
1469 /* For COND_EXPR we rearranged the arguments; undo that now. */
1472 TREE_VEC_ELT (convs, 2) = TREE_VEC_ELT (convs, 1);
1473 TREE_VEC_ELT (convs, 1) = TREE_VEC_ELT (convs, 0);
1474 t = implicit_conversion (boolean_type_node, argtypes[2], args[2], flags);
1476 TREE_VEC_ELT (convs, 0) = t;
1481 add_candidate (candidates, fnname, /*args=*/NULL_TREE, convs,
1482 /*access_path=*/NULL_TREE,
1483 /*conversion_path=*/NULL_TREE,
1488 is_complete (tree t)
1490 return COMPLETE_TYPE_P (complete_type (t));
1493 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1496 promoted_arithmetic_type_p (tree type)
1500 In this section, the term promoted integral type is used to refer
1501 to those integral types which are preserved by integral promotion
1502 (including e.g. int and long but excluding e.g. char).
1503 Similarly, the term promoted arithmetic type refers to promoted
1504 integral types plus floating types. */
1505 return ((INTEGRAL_TYPE_P (type)
1506 && same_type_p (type_promotes_to (type), type))
1507 || TREE_CODE (type) == REAL_TYPE);
1510 /* Create any builtin operator overload candidates for the operator in
1511 question given the converted operand types TYPE1 and TYPE2. The other
1512 args are passed through from add_builtin_candidates to
1513 build_builtin_candidate.
1515 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1516 If CODE is requires candidates operands of the same type of the kind
1517 of which TYPE1 and TYPE2 are, we add both candidates
1518 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1521 add_builtin_candidate (struct z_candidate **candidates, enum tree_code code,
1522 enum tree_code code2, tree fnname, tree type1,
1523 tree type2, tree *args, tree *argtypes, int flags)
1527 case POSTINCREMENT_EXPR:
1528 case POSTDECREMENT_EXPR:
1529 args[1] = integer_zero_node;
1530 type2 = integer_type_node;
1539 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1540 and VQ is either volatile or empty, there exist candidate operator
1541 functions of the form
1542 VQ T& operator++(VQ T&);
1543 T operator++(VQ T&, int);
1544 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1545 type other than bool, and VQ is either volatile or empty, there exist
1546 candidate operator functions of the form
1547 VQ T& operator--(VQ T&);
1548 T operator--(VQ T&, int);
1549 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1550 complete object type, and VQ is either volatile or empty, there exist
1551 candidate operator functions of the form
1552 T*VQ& operator++(T*VQ&);
1553 T*VQ& operator--(T*VQ&);
1554 T* operator++(T*VQ&, int);
1555 T* operator--(T*VQ&, int); */
1557 case POSTDECREMENT_EXPR:
1558 case PREDECREMENT_EXPR:
1559 if (TREE_CODE (type1) == BOOLEAN_TYPE)
1561 case POSTINCREMENT_EXPR:
1562 case PREINCREMENT_EXPR:
1563 if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
1565 type1 = build_reference_type (type1);
1570 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1571 exist candidate operator functions of the form
1575 8 For every function type T, there exist candidate operator functions of
1577 T& operator*(T*); */
1580 if (TREE_CODE (type1) == POINTER_TYPE
1581 && (TYPE_PTROB_P (type1)
1582 || TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
1586 /* 9 For every type T, there exist candidate operator functions of the form
1589 10For every promoted arithmetic type T, there exist candidate operator
1590 functions of the form
1594 case CONVERT_EXPR: /* unary + */
1595 if (TREE_CODE (type1) == POINTER_TYPE
1596 && TREE_CODE (TREE_TYPE (type1)) != OFFSET_TYPE)
1599 if (ARITHMETIC_TYPE_P (type1))
1603 /* 11For every promoted integral type T, there exist candidate operator
1604 functions of the form
1608 if (INTEGRAL_TYPE_P (type1))
1612 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1613 is the same type as C2 or is a derived class of C2, T is a complete
1614 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1615 there exist candidate operator functions of the form
1616 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1617 where CV12 is the union of CV1 and CV2. */
1620 if (TREE_CODE (type1) == POINTER_TYPE
1621 && (TYPE_PTRMEMFUNC_P (type2) || TYPE_PTRMEM_P (type2)))
1623 tree c1 = TREE_TYPE (type1);
1624 tree c2 = (TYPE_PTRMEMFUNC_P (type2)
1625 ? TYPE_METHOD_BASETYPE (TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (type2)))
1626 : TYPE_OFFSET_BASETYPE (TREE_TYPE (type2)));
1628 if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
1629 && (TYPE_PTRMEMFUNC_P (type2)
1630 || is_complete (TREE_TYPE (TREE_TYPE (type2)))))
1635 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1636 didate operator functions of the form
1641 bool operator<(L, R);
1642 bool operator>(L, R);
1643 bool operator<=(L, R);
1644 bool operator>=(L, R);
1645 bool operator==(L, R);
1646 bool operator!=(L, R);
1647 where LR is the result of the usual arithmetic conversions between
1650 14For every pair of types T and I, where T is a cv-qualified or cv-
1651 unqualified complete object type and I is a promoted integral type,
1652 there exist candidate operator functions of the form
1653 T* operator+(T*, I);
1654 T& operator[](T*, I);
1655 T* operator-(T*, I);
1656 T* operator+(I, T*);
1657 T& operator[](I, T*);
1659 15For every T, where T is a pointer to complete object type, there exist
1660 candidate operator functions of the form112)
1661 ptrdiff_t operator-(T, T);
1663 16For every pointer or enumeration type T, there exist candidate operator
1664 functions of the form
1665 bool operator<(T, T);
1666 bool operator>(T, T);
1667 bool operator<=(T, T);
1668 bool operator>=(T, T);
1669 bool operator==(T, T);
1670 bool operator!=(T, T);
1672 17For every pointer to member type T, there exist candidate operator
1673 functions of the form
1674 bool operator==(T, T);
1675 bool operator!=(T, T); */
1678 if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
1680 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1682 type2 = ptrdiff_type_node;
1686 case TRUNC_DIV_EXPR:
1687 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1693 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1694 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
1696 if ((TYPE_PTRMEMFUNC_P (type1) || TYPE_PTRMEM_P (type1))
1697 && null_ptr_cst_p (args[1]))
1702 if ((TYPE_PTRMEMFUNC_P (type2) || TYPE_PTRMEM_P (type2))
1703 && null_ptr_cst_p (args[0]))
1715 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1717 if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1719 if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
1721 if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
1726 if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
1734 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1737 if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
1739 type1 = ptrdiff_type_node;
1742 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1744 type2 = ptrdiff_type_node;
1749 /* 18For every pair of promoted integral types L and R, there exist candi-
1750 date operator functions of the form
1757 where LR is the result of the usual arithmetic conversions between
1760 case TRUNC_MOD_EXPR:
1766 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1770 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
1771 type, VQ is either volatile or empty, and R is a promoted arithmetic
1772 type, there exist candidate operator functions of the form
1773 VQ L& operator=(VQ L&, R);
1774 VQ L& operator*=(VQ L&, R);
1775 VQ L& operator/=(VQ L&, R);
1776 VQ L& operator+=(VQ L&, R);
1777 VQ L& operator-=(VQ L&, R);
1779 20For every pair T, VQ), where T is any type and VQ is either volatile
1780 or empty, there exist candidate operator functions of the form
1781 T*VQ& operator=(T*VQ&, T*);
1783 21For every pair T, VQ), where T is a pointer to member type and VQ is
1784 either volatile or empty, there exist candidate operator functions of
1786 VQ T& operator=(VQ T&, T);
1788 22For every triple T, VQ, I), where T is a cv-qualified or cv-
1789 unqualified complete object type, VQ is either volatile or empty, and
1790 I is a promoted integral type, there exist candidate operator func-
1792 T*VQ& operator+=(T*VQ&, I);
1793 T*VQ& operator-=(T*VQ&, I);
1795 23For every triple L, VQ, R), where L is an integral or enumeration
1796 type, VQ is either volatile or empty, and R is a promoted integral
1797 type, there exist candidate operator functions of the form
1799 VQ L& operator%=(VQ L&, R);
1800 VQ L& operator<<=(VQ L&, R);
1801 VQ L& operator>>=(VQ L&, R);
1802 VQ L& operator&=(VQ L&, R);
1803 VQ L& operator^=(VQ L&, R);
1804 VQ L& operator|=(VQ L&, R); */
1811 if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
1813 type2 = ptrdiff_type_node;
1817 case TRUNC_DIV_EXPR:
1818 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1822 case TRUNC_MOD_EXPR:
1828 if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
1833 if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
1835 if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
1836 || (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
1837 || (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
1838 || ((TYPE_PTRMEMFUNC_P (type1)
1839 || TREE_CODE (type1) == POINTER_TYPE)
1840 && null_ptr_cst_p (args[1])))
1850 type1 = build_reference_type (type1);
1856 For every pair of promoted arithmetic types L and R, there
1857 exist candidate operator functions of the form
1859 LR operator?(bool, L, R);
1861 where LR is the result of the usual arithmetic conversions
1862 between types L and R.
1864 For every type T, where T is a pointer or pointer-to-member
1865 type, there exist candidate operator functions of the form T
1866 operator?(bool, T, T); */
1868 if (promoted_arithmetic_type_p (type1)
1869 && promoted_arithmetic_type_p (type2))
1873 /* Otherwise, the types should be pointers. */
1874 if (!(TREE_CODE (type1) == POINTER_TYPE
1875 || TYPE_PTRMEM_P (type1)
1876 || TYPE_PTRMEMFUNC_P (type1))
1877 || !(TREE_CODE (type2) == POINTER_TYPE
1878 || TYPE_PTRMEM_P (type2)
1879 || TYPE_PTRMEMFUNC_P (type2)))
1882 /* We don't check that the two types are the same; the logic
1883 below will actually create two candidates; one in which both
1884 parameter types are TYPE1, and one in which both parameter
1892 /* If we're dealing with two pointer types or two enumeral types,
1893 we need candidates for both of them. */
1894 if (type2 && !same_type_p (type1, type2)
1895 && TREE_CODE (type1) == TREE_CODE (type2)
1896 && (TREE_CODE (type1) == REFERENCE_TYPE
1897 || (TREE_CODE (type1) == POINTER_TYPE
1898 && TYPE_PTRMEM_P (type1) == TYPE_PTRMEM_P (type2))
1899 || TYPE_PTRMEMFUNC_P (type1)
1900 || IS_AGGR_TYPE (type1)
1901 || TREE_CODE (type1) == ENUMERAL_TYPE))
1903 build_builtin_candidate
1904 (candidates, fnname, type1, type1, args, argtypes, flags);
1905 build_builtin_candidate
1906 (candidates, fnname, type2, type2, args, argtypes, flags);
1910 build_builtin_candidate
1911 (candidates, fnname, type1, type2, args, argtypes, flags);
1915 type_decays_to (tree type)
1917 if (TREE_CODE (type) == ARRAY_TYPE)
1918 return build_pointer_type (TREE_TYPE (type));
1919 if (TREE_CODE (type) == FUNCTION_TYPE)
1920 return build_pointer_type (type);
1924 /* There are three conditions of builtin candidates:
1926 1) bool-taking candidates. These are the same regardless of the input.
1927 2) pointer-pair taking candidates. These are generated for each type
1928 one of the input types converts to.
1929 3) arithmetic candidates. According to the standard, we should generate
1930 all of these, but I'm trying not to...
1932 Here we generate a superset of the possible candidates for this particular
1933 case. That is a subset of the full set the standard defines, plus some
1934 other cases which the standard disallows. add_builtin_candidate will
1935 filter out the invalid set. */
1938 add_builtin_candidates (struct z_candidate **candidates, enum tree_code code,
1939 enum tree_code code2, tree fnname, tree *args,
1944 tree type, argtypes[3];
1945 /* TYPES[i] is the set of possible builtin-operator parameter types
1946 we will consider for the Ith argument. These are represented as
1947 a TREE_LIST; the TREE_VALUE of each node is the potential
1951 for (i = 0; i < 3; ++i)
1954 argtypes[i] = lvalue_type (args[i]);
1956 argtypes[i] = NULL_TREE;
1961 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1962 and VQ is either volatile or empty, there exist candidate operator
1963 functions of the form
1964 VQ T& operator++(VQ T&); */
1966 case POSTINCREMENT_EXPR:
1967 case PREINCREMENT_EXPR:
1968 case POSTDECREMENT_EXPR:
1969 case PREDECREMENT_EXPR:
1974 /* 24There also exist candidate operator functions of the form
1975 bool operator!(bool);
1976 bool operator&&(bool, bool);
1977 bool operator||(bool, bool); */
1979 case TRUTH_NOT_EXPR:
1980 build_builtin_candidate
1981 (candidates, fnname, boolean_type_node,
1982 NULL_TREE, args, argtypes, flags);
1985 case TRUTH_ORIF_EXPR:
1986 case TRUTH_ANDIF_EXPR:
1987 build_builtin_candidate
1988 (candidates, fnname, boolean_type_node,
1989 boolean_type_node, args, argtypes, flags);
2011 types[0] = types[1] = NULL_TREE;
2013 for (i = 0; i < 2; ++i)
2017 else if (IS_AGGR_TYPE (argtypes[i]))
2021 if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
2024 convs = lookup_conversions (argtypes[i]);
2026 if (code == COND_EXPR)
2028 if (real_lvalue_p (args[i]))
2029 types[i] = tree_cons
2030 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2032 types[i] = tree_cons
2033 (NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
2039 for (; convs; convs = TREE_CHAIN (convs))
2041 type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
2044 && (TREE_CODE (type) != REFERENCE_TYPE
2045 || CP_TYPE_CONST_P (TREE_TYPE (type))))
2048 if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
2049 types[i] = tree_cons (NULL_TREE, type, types[i]);
2051 type = non_reference (type);
2052 if (i != 0 || ! ref1)
2054 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2055 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2056 types[i] = tree_cons (NULL_TREE, type, types[i]);
2057 if (INTEGRAL_TYPE_P (type))
2058 type = type_promotes_to (type);
2061 if (! value_member (type, types[i]))
2062 types[i] = tree_cons (NULL_TREE, type, types[i]);
2067 if (code == COND_EXPR && real_lvalue_p (args[i]))
2068 types[i] = tree_cons
2069 (NULL_TREE, build_reference_type (argtypes[i]), types[i]);
2070 type = non_reference (argtypes[i]);
2071 if (i != 0 || ! ref1)
2073 type = TYPE_MAIN_VARIANT (type_decays_to (type));
2074 if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
2075 types[i] = tree_cons (NULL_TREE, type, types[i]);
2076 if (INTEGRAL_TYPE_P (type))
2077 type = type_promotes_to (type);
2079 types[i] = tree_cons (NULL_TREE, type, types[i]);
2083 /* Run through the possible parameter types of both arguments,
2084 creating candidates with those parameter types. */
2085 for (; types[0]; types[0] = TREE_CHAIN (types[0]))
2088 for (type = types[1]; type; type = TREE_CHAIN (type))
2089 add_builtin_candidate
2090 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2091 TREE_VALUE (type), args, argtypes, flags);
2093 add_builtin_candidate
2094 (candidates, code, code2, fnname, TREE_VALUE (types[0]),
2095 NULL_TREE, args, argtypes, flags);
2102 /* If TMPL can be successfully instantiated as indicated by
2103 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2105 TMPL is the template. EXPLICIT_TARGS are any explicit template
2106 arguments. ARGLIST is the arguments provided at the call-site.
2107 The RETURN_TYPE is the desired type for conversion operators. If
2108 OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
2109 If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
2110 add_conv_candidate. */
2112 static struct z_candidate*
2113 add_template_candidate_real (struct z_candidate **candidates, tree tmpl,
2114 tree ctype, tree explicit_targs, tree arglist,
2115 tree return_type, tree access_path,
2116 tree conversion_path, int flags, tree obj,
2117 unification_kind_t strict)
2119 int ntparms = DECL_NTPARMS (tmpl);
2120 tree targs = make_tree_vec (ntparms);
2121 tree args_without_in_chrg = arglist;
2122 struct z_candidate *cand;
2126 /* We don't do deduction on the in-charge parameter, the VTT
2127 parameter or 'this'. */
2128 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
2129 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2131 if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
2132 || DECL_BASE_CONSTRUCTOR_P (tmpl))
2133 && TYPE_USES_VIRTUAL_BASECLASSES (DECL_CONTEXT (tmpl)))
2134 args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
2136 i = fn_type_unification (tmpl, explicit_targs, targs,
2137 args_without_in_chrg,
2138 return_type, strict, -1);
2143 fn = instantiate_template (tmpl, targs, tf_none);
2144 if (fn == error_mark_node)
2149 A member function template is never instantiated to perform the
2150 copy of a class object to an object of its class type.
2152 It's a little unclear what this means; the standard explicitly
2153 does allow a template to be used to copy a class. For example,
2158 template <class T> A(const T&);
2161 void g () { A a (f ()); }
2163 the member template will be used to make the copy. The section
2164 quoted above appears in the paragraph that forbids constructors
2165 whose only parameter is (a possibly cv-qualified variant of) the
2166 class type, and a logical interpretation is that the intent was
2167 to forbid the instantiation of member templates which would then
2169 if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
2171 tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
2172 if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
2177 if (obj != NULL_TREE)
2178 /* Aha, this is a conversion function. */
2179 cand = add_conv_candidate (candidates, fn, obj, access_path,
2180 conversion_path, arglist);
2182 cand = add_function_candidate (candidates, fn, ctype,
2183 arglist, access_path,
2184 conversion_path, flags);
2185 if (DECL_TI_TEMPLATE (fn) != tmpl)
2186 /* This situation can occur if a member template of a template
2187 class is specialized. Then, instantiate_template might return
2188 an instantiation of the specialization, in which case the
2189 DECL_TI_TEMPLATE field will point at the original
2190 specialization. For example:
2192 template <class T> struct S { template <class U> void f(U);
2193 template <> void f(int) {}; };
2197 Here, TMPL will be template <class U> S<double>::f(U).
2198 And, instantiate template will give us the specialization
2199 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2200 for this will point at template <class T> template <> S<T>::f(int),
2201 so that we can find the definition. For the purposes of
2202 overload resolution, however, we want the original TMPL. */
2203 cand->template = tree_cons (tmpl, targs, NULL_TREE);
2205 cand->template = DECL_TEMPLATE_INFO (fn);
2211 static struct z_candidate *
2212 add_template_candidate (struct z_candidate **candidates, tree tmpl, tree ctype,
2213 tree explicit_targs, tree arglist, tree return_type,
2214 tree access_path, tree conversion_path, int flags,
2215 unification_kind_t strict)
2218 add_template_candidate_real (candidates, tmpl, ctype,
2219 explicit_targs, arglist, return_type,
2220 access_path, conversion_path,
2221 flags, NULL_TREE, strict);
2225 static struct z_candidate *
2226 add_template_conv_candidate (struct z_candidate **candidates, tree tmpl,
2227 tree obj, tree arglist, tree return_type,
2228 tree access_path, tree conversion_path)
2231 add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
2232 arglist, return_type, access_path,
2233 conversion_path, 0, obj, DEDUCE_CONV);
2236 /* The CANDS are the set of candidates that were considered for
2237 overload resolution. Return the set of viable candidates. If none
2238 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2239 is true if a candidate should be considered viable only if it is
2242 static struct z_candidate*
2243 splice_viable (struct z_candidate *cands,
2247 struct z_candidate *viable;
2248 struct z_candidate **last_viable;
2249 struct z_candidate **cand;
2252 last_viable = &viable;
2253 *any_viable_p = false;
2258 struct z_candidate *c = *cand;
2259 if (strict_p ? c->viable == 1 : c->viable)
2264 last_viable = &c->next;
2265 *any_viable_p = true;
2271 return viable ? viable : cands;
2275 any_strictly_viable (struct z_candidate *cands)
2277 for (; cands; cands = cands->next)
2278 if (cands->viable == 1)
2284 build_this (tree obj)
2286 /* Fix this to work on non-lvalues. */
2287 return build_unary_op (ADDR_EXPR, obj, 0);
2290 /* Returns true iff functions are equivalent. Equivalent functions are
2291 not '==' only if one is a function-local extern function or if
2292 both are extern "C". */
2295 equal_functions (tree fn1, tree fn2)
2297 if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
2298 || DECL_EXTERN_C_FUNCTION_P (fn1))
2299 return decls_match (fn1, fn2);
2303 /* Print information about one overload candidate CANDIDATE. MSGSTR
2304 is the text to print before the candidate itself.
2306 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2307 to have been run through gettext by the caller. This wart makes
2308 life simpler in print_z_candidates and for the translators. */
2311 print_z_candidate (const char *msgstr, struct z_candidate *candidate)
2313 if (TREE_CODE (candidate->fn) == IDENTIFIER_NODE)
2315 if (TREE_VEC_LENGTH (candidate->convs) == 3)
2316 inform ("%s %D(%T, %T, %T) <built-in>", msgstr, candidate->fn,
2317 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
2318 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)),
2319 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 2)));
2320 else if (TREE_VEC_LENGTH (candidate->convs) == 2)
2321 inform ("%s %D(%T, %T) <built-in>", msgstr, candidate->fn,
2322 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)),
2323 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 1)));
2325 inform ("%s %D(%T) <built-in>", msgstr, candidate->fn,
2326 TREE_TYPE (TREE_VEC_ELT (candidate->convs, 0)));
2328 else if (TYPE_P (candidate->fn))
2329 inform ("%s %T <conversion>", msgstr, candidate->fn);
2330 else if (candidate->viable == -1)
2331 inform ("%H%s %+#D <near match>",
2332 &DECL_SOURCE_LOCATION (candidate->fn), msgstr, candidate->fn);
2334 inform ("%H%s %+#D",
2335 &DECL_SOURCE_LOCATION (candidate->fn), msgstr, candidate->fn);
2339 print_z_candidates (struct z_candidate *candidates)
2342 struct z_candidate *cand1;
2343 struct z_candidate **cand2;
2345 /* There may be duplicates in the set of candidates. We put off
2346 checking this condition as long as possible, since we have no way
2347 to eliminate duplicates from a set of functions in less than n^2
2348 time. Now we are about to emit an error message, so it is more
2349 permissible to go slowly. */
2350 for (cand1 = candidates; cand1; cand1 = cand1->next)
2352 tree fn = cand1->fn;
2353 /* Skip builtin candidates and conversion functions. */
2354 if (TREE_CODE (fn) != FUNCTION_DECL)
2356 cand2 = &cand1->next;
2359 if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
2360 && equal_functions (fn, (*cand2)->fn))
2361 *cand2 = (*cand2)->next;
2363 cand2 = &(*cand2)->next;
2370 str = _("candidates are:");
2371 print_z_candidate (str, candidates);
2372 if (candidates->next)
2374 /* Indent successive candidates by the width of the translation
2375 of the above string. */
2376 size_t len = gcc_gettext_width (str) + 1;
2377 char *spaces = alloca (len);
2378 memset (spaces, ' ', len-1);
2379 spaces[len - 1] = '\0';
2381 candidates = candidates->next;
2384 print_z_candidate (spaces, candidates);
2385 candidates = candidates->next;
2391 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2392 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2393 the result of the conversion function to convert it to the final
2394 desired type. Merge the the two sequences into a single sequence,
2395 and return the merged sequence. */
2398 merge_conversion_sequences (tree user_seq, tree std_seq)
2402 my_friendly_assert (TREE_CODE (user_seq) == USER_CONV,
2405 /* Find the end of the second conversion sequence. */
2407 while (TREE_CODE (*t) != IDENTITY_CONV)
2408 t = &TREE_OPERAND (*t, 0);
2410 /* Replace the identity conversion with the user conversion
2414 /* The entire sequence is a user-conversion sequence. */
2415 ICS_USER_FLAG (std_seq) = 1;
2420 /* Returns the best overload candidate to perform the requested
2421 conversion. This function is used for three the overloading situations
2422 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2423 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2424 per [dcl.init.ref], so we ignore temporary bindings. */
2426 static struct z_candidate *
2427 build_user_type_conversion_1 (tree totype, tree expr, int flags)
2429 struct z_candidate *candidates, *cand;
2430 tree fromtype = TREE_TYPE (expr);
2431 tree ctors = NULL_TREE, convs = NULL_TREE;
2432 tree args = NULL_TREE;
2435 /* We represent conversion within a hierarchy using RVALUE_CONV and
2436 BASE_CONV, as specified by [over.best.ics]; these become plain
2437 constructor calls, as specified in [dcl.init]. */
2438 my_friendly_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
2439 || !DERIVED_FROM_P (totype, fromtype), 20011226);
2441 if (IS_AGGR_TYPE (totype))
2442 ctors = lookup_fnfields (TYPE_BINFO (totype),
2443 complete_ctor_identifier,
2446 if (IS_AGGR_TYPE (fromtype))
2447 convs = lookup_conversions (fromtype);
2450 flags |= LOOKUP_NO_CONVERSION;
2456 ctors = BASELINK_FUNCTIONS (ctors);
2458 t = build_int_2 (0, 0);
2459 TREE_TYPE (t) = build_pointer_type (totype);
2460 args = build_tree_list (NULL_TREE, expr);
2461 /* We should never try to call the abstract or base constructor
2463 my_friendly_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
2464 && !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)),
2466 args = tree_cons (NULL_TREE, t, args);
2468 for (; ctors; ctors = OVL_NEXT (ctors))
2470 tree ctor = OVL_CURRENT (ctors);
2471 if (DECL_NONCONVERTING_P (ctor))
2474 if (TREE_CODE (ctor) == TEMPLATE_DECL)
2475 cand = add_template_candidate (&candidates, ctor, totype,
2476 NULL_TREE, args, NULL_TREE,
2477 TYPE_BINFO (totype),
2478 TYPE_BINFO (totype),
2482 cand = add_function_candidate (&candidates, ctor, totype,
2483 args, TYPE_BINFO (totype),
2484 TYPE_BINFO (totype),
2488 cand->second_conv = build1 (IDENTITY_CONV, totype, NULL_TREE);
2492 args = build_tree_list (NULL_TREE, build_this (expr));
2494 for (; convs; convs = TREE_CHAIN (convs))
2497 tree conversion_path = TREE_PURPOSE (convs);
2498 int convflags = LOOKUP_NO_CONVERSION;
2500 /* If we are called to convert to a reference type, we are trying to
2501 find an lvalue binding, so don't even consider temporaries. If
2502 we don't find an lvalue binding, the caller will try again to
2503 look for a temporary binding. */
2504 if (TREE_CODE (totype) == REFERENCE_TYPE)
2505 convflags |= LOOKUP_NO_TEMP_BIND;
2507 for (fns = TREE_VALUE (convs); fns; fns = OVL_NEXT (fns))
2509 tree fn = OVL_CURRENT (fns);
2511 /* [over.match.funcs] For conversion functions, the function
2512 is considered to be a member of the class of the implicit
2513 object argument for the purpose of defining the type of
2514 the implicit object parameter.
2516 So we pass fromtype as CTYPE to add_*_candidate. */
2518 if (TREE_CODE (fn) == TEMPLATE_DECL)
2519 cand = add_template_candidate (&candidates, fn, fromtype,
2522 TYPE_BINFO (fromtype),
2527 cand = add_function_candidate (&candidates, fn, fromtype,
2529 TYPE_BINFO (fromtype),
2535 tree ics = implicit_conversion (totype,
2536 TREE_TYPE (TREE_TYPE (cand->fn)),
2539 cand->second_conv = ics;
2541 if (ics == NULL_TREE)
2543 else if (candidates->viable == 1 && ICS_BAD_FLAG (ics))
2549 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2553 cand = tourney (candidates);
2556 if (flags & LOOKUP_COMPLAIN)
2558 error ("conversion from `%T' to `%T' is ambiguous",
2560 print_z_candidates (candidates);
2563 cand = candidates; /* any one will do */
2564 cand->second_conv = build1 (AMBIG_CONV, totype, expr);
2565 ICS_USER_FLAG (cand->second_conv) = 1;
2566 if (!any_strictly_viable (candidates))
2567 ICS_BAD_FLAG (cand->second_conv) = 1;
2568 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
2569 ambiguous conversion is no worse than another user-defined
2575 /* Build the user conversion sequence. */
2578 (DECL_CONSTRUCTOR_P (cand->fn)
2579 ? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
2580 build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
2581 TREE_OPERAND (convs, 1) = build_zc_wrapper (cand);
2583 /* Combine it with the second conversion sequence. */
2584 cand->second_conv = merge_conversion_sequences (convs,
2587 if (cand->viable == -1)
2588 ICS_BAD_FLAG (cand->second_conv) = 1;
2594 build_user_type_conversion (tree totype, tree expr, int flags)
2596 struct z_candidate *cand
2597 = build_user_type_conversion_1 (totype, expr, flags);
2601 if (TREE_CODE (cand->second_conv) == AMBIG_CONV)
2602 return error_mark_node;
2603 return convert_from_reference (convert_like (cand->second_conv, expr));
2608 /* Find the possibly overloaded set of functions corresponding to a
2609 call of the form SCOPE::NAME (...). NAME might be a
2610 TEMPLATE_ID_EXPR, OVERLOAD, _DECL, or IDENTIFIER_NODE. */
2613 resolve_scoped_fn_name (tree scope, tree name)
2615 tree fn = NULL_TREE;
2616 tree template_args = NULL_TREE;
2617 bool is_template_id = TREE_CODE (name) == TEMPLATE_ID_EXPR;
2621 template_args = TREE_OPERAND (name, 1);
2622 name = TREE_OPERAND (name, 0);
2624 if (TREE_CODE (name) == OVERLOAD)
2625 name = DECL_NAME (get_first_fn (name));
2627 if (TREE_CODE (scope) == NAMESPACE_DECL)
2628 fn = lookup_namespace_name (scope, name);
2629 else if (!CLASS_TYPE_P (scope))
2631 error ("`%T' is not a class type", scope);
2632 return error_mark_node;
2636 if (!TYPE_BEING_DEFINED (scope)
2637 && !COMPLETE_TYPE_P (complete_type (scope)))
2639 error ("incomplete type '%T' cannot be used to name a scope",
2641 return error_mark_node;
2644 if (BASELINK_P (name))
2647 fn = lookup_member (scope, name, /*protect=*/1, /*want_type=*/false);
2648 if (fn && current_class_type)
2649 fn = (adjust_result_of_qualified_name_lookup
2650 (fn, scope, current_class_type));
2652 /* It might be the name of a function pointer member. */
2653 if (fn && TREE_CODE (fn) == FIELD_DECL)
2654 fn = finish_non_static_data_member (fn, scope);
2659 error ("'%D' has no member named '%E'", scope, name);
2660 return error_mark_node;
2666 if (BASELINK_P (fn))
2667 fns = BASELINK_FUNCTIONS (fns);
2668 fns = build_nt (TEMPLATE_ID_EXPR, fns, template_args);
2669 if (BASELINK_P (fn))
2670 BASELINK_FUNCTIONS (fn) = fns;
2678 /* Do any initial processing on the arguments to a function call. */
2681 resolve_args (tree args)
2684 for (t = args; t; t = TREE_CHAIN (t))
2686 tree arg = TREE_VALUE (t);
2688 if (arg == error_mark_node)
2689 return error_mark_node;
2690 else if (VOID_TYPE_P (TREE_TYPE (arg)))
2692 error ("invalid use of void expression");
2693 return error_mark_node;
2695 arg = convert_from_reference (arg);
2696 TREE_VALUE (t) = arg;
2701 /* Perform overload resolution on FN, which is called with the ARGS.
2703 Return the candidate function selected by overload resolution, or
2704 NULL if the event that overload resolution failed. In the case
2705 that overload resolution fails, *CANDIDATES will be the set of
2706 candidates considered, and ANY_VIABLE_P will be set to true or
2707 false to indicate whether or not any of the candidates were
2710 The ARGS should already have gone through RESOLVE_ARGS before this
2711 function is called. */
2713 static struct z_candidate *
2714 perform_overload_resolution (tree fn,
2716 struct z_candidate **candidates,
2719 struct z_candidate *cand;
2720 tree explicit_targs = NULL_TREE;
2721 int template_only = 0;
2724 *any_viable_p = true;
2726 /* Check FN and ARGS. */
2727 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
2728 || TREE_CODE (fn) == TEMPLATE_DECL
2729 || TREE_CODE (fn) == OVERLOAD
2730 || TREE_CODE (fn) == TEMPLATE_ID_EXPR,
2732 my_friendly_assert (!args || TREE_CODE (args) == TREE_LIST,
2735 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2737 explicit_targs = TREE_OPERAND (fn, 1);
2738 fn = TREE_OPERAND (fn, 0);
2742 /* Add the various candidate functions. */
2743 add_candidates (fn, args, explicit_targs, template_only,
2744 /*conversion_path=*/NULL_TREE,
2745 /*access_path=*/NULL_TREE,
2749 *candidates = splice_viable (*candidates, pedantic, any_viable_p);
2753 cand = tourney (*candidates);
2757 /* Return an expression for a call to FN (a namespace-scope function,
2758 or a static member function) with the ARGS. */
2761 build_new_function_call (tree fn, tree args)
2763 struct z_candidate *candidates, *cand;
2766 args = resolve_args (args);
2767 if (args == error_mark_node)
2768 return error_mark_node;
2770 cand = perform_overload_resolution (fn, args, &candidates, &any_viable_p);
2774 if (!any_viable_p && candidates && ! candidates->next)
2775 return build_function_call (candidates->fn, args);
2776 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2777 fn = TREE_OPERAND (fn, 0);
2779 error ("no matching function for call to `%D(%A)'",
2780 DECL_NAME (OVL_CURRENT (fn)), args);
2782 error ("call of overloaded `%D(%A)' is ambiguous",
2783 DECL_NAME (OVL_CURRENT (fn)), args);
2785 print_z_candidates (candidates);
2786 return error_mark_node;
2789 return build_over_call (cand, LOOKUP_NORMAL);
2792 /* Build a call to a global operator new. FNNAME is the name of the
2793 operator (either "operator new" or "operator new[]") and ARGS are
2794 the arguments provided. *SIZE points to the total number of bytes
2795 required by the allocation, and is updated if that is changed here.
2796 *COOKIE_SIZE is non-NULL if a cookie should be used. If this
2797 function determines that no cookie should be used, after all,
2798 *COOKIE_SIZE is set to NULL_TREE. */
2801 build_operator_new_call (tree fnname, tree args, tree *size, tree *cookie_size)
2804 struct z_candidate *candidates;
2805 struct z_candidate *cand;
2808 args = tree_cons (NULL_TREE, *size, args);
2809 args = resolve_args (args);
2810 if (args == error_mark_node)
2813 fns = lookup_function_nonclass (fnname, args);
2815 /* Figure out what function is being called. */
2816 cand = perform_overload_resolution (fns, args, &candidates, &any_viable_p);
2818 /* If no suitable function could be found, issue an error message
2823 error ("no matching function for call to `%D(%A)'",
2824 DECL_NAME (OVL_CURRENT (fns)), args);
2826 error ("call of overloaded `%D(%A)' is ambiguous",
2827 DECL_NAME (OVL_CURRENT (fns)), args);
2829 print_z_candidates (candidates);
2830 return error_mark_node;
2833 /* If a cookie is required, add some extra space. Whether
2834 or not a cookie is required cannot be determined until
2835 after we know which function was called. */
2838 bool use_cookie = true;
2839 if (!abi_version_at_least (2))
2841 tree placement = TREE_CHAIN (args);
2842 /* In G++ 3.2, the check was implemented incorrectly; it
2843 looked at the placement expression, rather than the
2844 type of the function. */
2845 if (placement && !TREE_CHAIN (placement)
2846 && same_type_p (TREE_TYPE (TREE_VALUE (placement)),
2854 arg_types = TYPE_ARG_TYPES (TREE_TYPE (cand->fn));
2855 /* Skip the size_t parameter. */
2856 arg_types = TREE_CHAIN (arg_types);
2857 /* Check the remaining parameters (if any). */
2859 && TREE_CHAIN (arg_types) == void_list_node
2860 && same_type_p (TREE_VALUE (arg_types),
2864 /* If we need a cookie, adjust the number of bytes allocated. */
2867 /* Update the total size. */
2868 *size = size_binop (PLUS_EXPR, *size, *cookie_size);
2869 /* Update the argument list to reflect the adjusted size. */
2870 TREE_VALUE (args) = *size;
2873 *cookie_size = NULL_TREE;
2876 /* Build the CALL_EXPR. */
2877 return build_over_call (cand, LOOKUP_NORMAL);
2881 build_object_call (tree obj, tree args)
2883 struct z_candidate *candidates = 0, *cand;
2884 tree fns, convs, mem_args = NULL_TREE;
2885 tree type = TREE_TYPE (obj);
2888 if (TYPE_PTRMEMFUNC_P (type))
2890 /* It's no good looking for an overloaded operator() on a
2891 pointer-to-member-function. */
2892 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
2893 return error_mark_node;
2896 fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
2897 if (fns == error_mark_node)
2898 return error_mark_node;
2900 args = resolve_args (args);
2902 if (args == error_mark_node)
2903 return error_mark_node;
2907 tree base = BINFO_TYPE (BASELINK_BINFO (fns));
2908 mem_args = tree_cons (NULL_TREE, build_this (obj), args);
2910 for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
2912 tree fn = OVL_CURRENT (fns);
2913 if (TREE_CODE (fn) == TEMPLATE_DECL)
2914 add_template_candidate (&candidates, fn, base, NULL_TREE,
2915 mem_args, NULL_TREE,
2918 LOOKUP_NORMAL, DEDUCE_CALL);
2920 add_function_candidate
2921 (&candidates, fn, base, mem_args, TYPE_BINFO (type),
2922 TYPE_BINFO (type), LOOKUP_NORMAL);
2926 convs = lookup_conversions (type);
2928 for (; convs; convs = TREE_CHAIN (convs))
2930 tree fns = TREE_VALUE (convs);
2931 tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
2933 if ((TREE_CODE (totype) == POINTER_TYPE
2934 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2935 || (TREE_CODE (totype) == REFERENCE_TYPE
2936 && TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
2937 || (TREE_CODE (totype) == REFERENCE_TYPE
2938 && TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
2939 && TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
2940 for (; fns; fns = OVL_NEXT (fns))
2942 tree fn = OVL_CURRENT (fns);
2943 if (TREE_CODE (fn) == TEMPLATE_DECL)
2944 add_template_conv_candidate
2945 (&candidates, fn, obj, args, totype,
2946 /*access_path=*/NULL_TREE,
2947 /*conversion_path=*/NULL_TREE);
2949 add_conv_candidate (&candidates, fn, obj, args,
2950 /*conversion_path=*/NULL_TREE,
2951 /*access_path=*/NULL_TREE);
2955 candidates = splice_viable (candidates, pedantic, &any_viable_p);
2958 error ("no match for call to `(%T) (%A)'", TREE_TYPE (obj), args);
2959 print_z_candidates (candidates);
2960 return error_mark_node;
2963 cand = tourney (candidates);
2966 error ("call of `(%T) (%A)' is ambiguous", TREE_TYPE (obj), args);
2967 print_z_candidates (candidates);
2968 return error_mark_node;
2971 /* Since cand->fn will be a type, not a function, for a conversion
2972 function, we must be careful not to unconditionally look at
2974 if (TREE_CODE (cand->fn) == FUNCTION_DECL
2975 && DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
2976 return build_over_call (cand, LOOKUP_NORMAL);
2978 obj = convert_like_with_context
2979 (TREE_VEC_ELT (cand->convs, 0), obj, cand->fn, -1);
2982 return build_function_call (obj, args);
2986 op_error (enum tree_code code, enum tree_code code2,
2987 tree arg1, tree arg2, tree arg3, const char *problem)
2991 if (code == MODIFY_EXPR)
2992 opname = assignment_operator_name_info[code2].name;
2994 opname = operator_name_info[code].name;
2999 error ("%s for ternary 'operator?:' in '%E ? %E : %E'",
3000 problem, arg1, arg2, arg3);
3003 case POSTINCREMENT_EXPR:
3004 case POSTDECREMENT_EXPR:
3005 error ("%s for 'operator%s' in '%E%s'", problem, opname, arg1, opname);
3009 error ("%s for 'operator[]' in '%E[%E]'", problem, arg1, arg2);
3014 error ("%s for '%s' in '%s %E'", problem, opname, opname, arg1);
3019 error ("%s for 'operator%s' in '%E %s %E'",
3020 problem, opname, arg1, opname, arg2);
3022 error ("%s for 'operator%s' in '%s%E'",
3023 problem, opname, opname, arg1);
3028 /* Return the implicit conversion sequence that could be used to
3029 convert E1 to E2 in [expr.cond]. */
3032 conditional_conversion (tree e1, tree e2)
3034 tree t1 = non_reference (TREE_TYPE (e1));
3035 tree t2 = non_reference (TREE_TYPE (e2));
3041 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3042 implicitly converted (clause _conv_) to the type "reference to
3043 T2", subject to the constraint that in the conversion the
3044 reference must bind directly (_dcl.init.ref_) to E1. */
3045 if (real_lvalue_p (e2))
3047 conv = implicit_conversion (build_reference_type (t2),
3050 LOOKUP_NO_TEMP_BIND);
3057 If E1 and E2 have class type, and the underlying class types are
3058 the same or one is a base class of the other: E1 can be converted
3059 to match E2 if the class of T2 is the same type as, or a base
3060 class of, the class of T1, and the cv-qualification of T2 is the
3061 same cv-qualification as, or a greater cv-qualification than, the
3062 cv-qualification of T1. If the conversion is applied, E1 is
3063 changed to an rvalue of type T2 that still refers to the original
3064 source class object (or the appropriate subobject thereof).
3066 FIXME we can't express an rvalue that refers to the original object;
3067 we have to create a new one. */
3068 if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
3069 && ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
3071 if (good_base && at_least_as_qualified_p (t2, t1))
3073 conv = build1 (IDENTITY_CONV, t1, e1);
3074 if (!same_type_p (TYPE_MAIN_VARIANT (t1),
3075 TYPE_MAIN_VARIANT (t2)))
3077 conv = build_conv (BASE_CONV, t2, conv);
3078 NEED_TEMPORARY_P (conv) = 1;
3081 conv = build_conv (RVALUE_CONV, t2, conv);
3090 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3091 converted to the type that expression E2 would have if E2 were
3092 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3093 return implicit_conversion (t2, t1, e1, LOOKUP_NORMAL);
3096 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3097 arguments to the conditional expression. */
3100 build_conditional_expr (tree arg1, tree arg2, tree arg3)
3105 tree result_type = NULL_TREE;
3106 bool lvalue_p = true;
3107 struct z_candidate *candidates = 0;
3108 struct z_candidate *cand;
3110 /* As a G++ extension, the second argument to the conditional can be
3111 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3112 c'.) If the second operand is omitted, make sure it is
3113 calculated only once. */
3117 pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
3119 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3120 if (real_lvalue_p (arg1))
3121 arg2 = arg1 = stabilize_reference (arg1);
3123 arg2 = arg1 = save_expr (arg1);
3128 The first expr ession is implicitly converted to bool (clause
3130 arg1 = cp_convert (boolean_type_node, arg1);
3132 /* If something has already gone wrong, just pass that fact up the
3134 if (arg1 == error_mark_node
3135 || arg2 == error_mark_node
3136 || arg3 == error_mark_node
3137 || TREE_TYPE (arg1) == error_mark_node
3138 || TREE_TYPE (arg2) == error_mark_node
3139 || TREE_TYPE (arg3) == error_mark_node)
3140 return error_mark_node;
3144 If either the second or the third operand has type (possibly
3145 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3146 array-to-pointer (_conv.array_), and function-to-pointer
3147 (_conv.func_) standard conversions are performed on the second
3148 and third operands. */
3149 arg2_type = TREE_TYPE (arg2);
3150 arg3_type = TREE_TYPE (arg3);
3151 if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
3153 /* Do the conversions. We don't these for `void' type arguments
3154 since it can't have any effect and since decay_conversion
3155 does not handle that case gracefully. */
3156 if (!VOID_TYPE_P (arg2_type))
3157 arg2 = decay_conversion (arg2);
3158 if (!VOID_TYPE_P (arg3_type))
3159 arg3 = decay_conversion (arg3);
3160 arg2_type = TREE_TYPE (arg2);
3161 arg3_type = TREE_TYPE (arg3);
3165 One of the following shall hold:
3167 --The second or the third operand (but not both) is a
3168 throw-expression (_except.throw_); the result is of the
3169 type of the other and is an rvalue.
3171 --Both the second and the third operands have type void; the
3172 result is of type void and is an rvalue. */
3173 if ((TREE_CODE (arg2) == THROW_EXPR)
3174 ^ (TREE_CODE (arg3) == THROW_EXPR))
3175 result_type = ((TREE_CODE (arg2) == THROW_EXPR)
3176 ? arg3_type : arg2_type);
3177 else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
3178 result_type = void_type_node;
3181 error ("`%E' has type `void' and is not a throw-expression",
3182 VOID_TYPE_P (arg2_type) ? arg2 : arg3);
3183 return error_mark_node;
3187 goto valid_operands;
3191 Otherwise, if the second and third operand have different types,
3192 and either has (possibly cv-qualified) class type, an attempt is
3193 made to convert each of those operands to the type of the other. */
3194 else if (!same_type_p (arg2_type, arg3_type)
3195 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3197 tree conv2 = conditional_conversion (arg2, arg3);
3198 tree conv3 = conditional_conversion (arg3, arg2);
3202 If both can be converted, or one can be converted but the
3203 conversion is ambiguous, the program is ill-formed. If
3204 neither can be converted, the operands are left unchanged and
3205 further checking is performed as described below. If exactly
3206 one conversion is possible, that conversion is applied to the
3207 chosen operand and the converted operand is used in place of
3208 the original operand for the remainder of this section. */
3209 if ((conv2 && !ICS_BAD_FLAG (conv2)
3210 && conv3 && !ICS_BAD_FLAG (conv3))
3211 || (conv2 && TREE_CODE (conv2) == AMBIG_CONV)
3212 || (conv3 && TREE_CODE (conv3) == AMBIG_CONV))
3214 error ("operands to ?: have different types");
3215 return error_mark_node;
3217 else if (conv2 && !ICS_BAD_FLAG (conv2))
3219 arg2 = convert_like (conv2, arg2);
3220 arg2 = convert_from_reference (arg2);
3221 if (!same_type_p (TREE_TYPE (arg2), arg3_type))
3223 arg2_type = TREE_TYPE (arg2);
3225 else if (conv3 && !ICS_BAD_FLAG (conv3))
3227 arg3 = convert_like (conv3, arg3);
3228 arg3 = convert_from_reference (arg3);
3229 if (!same_type_p (TREE_TYPE (arg3), arg2_type))
3231 arg3_type = TREE_TYPE (arg3);
3237 If the second and third operands are lvalues and have the same
3238 type, the result is of that type and is an lvalue. */
3239 if (real_lvalue_p (arg2) && real_lvalue_p (arg3) &&
3240 same_type_p (arg2_type, arg3_type))
3242 result_type = arg2_type;
3243 goto valid_operands;
3248 Otherwise, the result is an rvalue. If the second and third
3249 operand do not have the same type, and either has (possibly
3250 cv-qualified) class type, overload resolution is used to
3251 determine the conversions (if any) to be applied to the operands
3252 (_over.match.oper_, _over.built_). */
3254 if (!same_type_p (arg2_type, arg3_type)
3255 && (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
3261 /* Rearrange the arguments so that add_builtin_candidate only has
3262 to know about two args. In build_builtin_candidates, the
3263 arguments are unscrambled. */
3267 add_builtin_candidates (&candidates,
3270 ansi_opname (COND_EXPR),
3276 If the overload resolution fails, the program is
3278 candidates = splice_viable (candidates, pedantic, &any_viable_p);
3281 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3282 print_z_candidates (candidates);
3283 return error_mark_node;
3285 cand = tourney (candidates);
3288 op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
3289 print_z_candidates (candidates);
3290 return error_mark_node;
3295 Otherwise, the conversions thus determined are applied, and
3296 the converted operands are used in place of the original
3297 operands for the remainder of this section. */
3298 conv = TREE_VEC_ELT (cand->convs, 0);
3299 arg1 = convert_like (conv, arg1);
3300 conv = TREE_VEC_ELT (cand->convs, 1);
3301 arg2 = convert_like (conv, arg2);
3302 conv = TREE_VEC_ELT (cand->convs, 2);
3303 arg3 = convert_like (conv, arg3);
3308 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3309 and function-to-pointer (_conv.func_) standard conversions are
3310 performed on the second and third operands.
3312 We need to force the lvalue-to-rvalue conversion here for class types,
3313 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3314 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3317 We use ocp_convert rather than build_user_type_conversion because the
3318 latter returns NULL_TREE on failure, while the former gives an error. */
3320 arg2 = force_rvalue (arg2);
3321 arg2_type = TREE_TYPE (arg2);
3323 arg3 = force_rvalue (arg3);
3324 arg3_type = TREE_TYPE (arg3);
3326 if (arg2 == error_mark_node || arg3 == error_mark_node)
3327 return error_mark_node;
3331 After those conversions, one of the following shall hold:
3333 --The second and third operands have the same type; the result is of
3335 if (same_type_p (arg2_type, arg3_type))
3336 result_type = arg2_type;
3339 --The second and third operands have arithmetic or enumeration
3340 type; the usual arithmetic conversions are performed to bring
3341 them to a common type, and the result is of that type. */
3342 else if ((ARITHMETIC_TYPE_P (arg2_type)
3343 || TREE_CODE (arg2_type) == ENUMERAL_TYPE)
3344 && (ARITHMETIC_TYPE_P (arg3_type)
3345 || TREE_CODE (arg3_type) == ENUMERAL_TYPE))
3347 /* In this case, there is always a common type. */
3348 result_type = type_after_usual_arithmetic_conversions (arg2_type,
3351 if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
3352 && TREE_CODE (arg3_type) == ENUMERAL_TYPE)
3353 warning ("enumeral mismatch in conditional expression: `%T' vs `%T'",
3354 arg2_type, arg3_type);
3355 else if (extra_warnings
3356 && ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
3357 && !same_type_p (arg3_type, type_promotes_to (arg2_type)))
3358 || (TREE_CODE (arg3_type) == ENUMERAL_TYPE
3359 && !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
3360 warning ("enumeral and non-enumeral type in conditional expression");
3362 arg2 = perform_implicit_conversion (result_type, arg2);
3363 arg3 = perform_implicit_conversion (result_type, arg3);
3367 --The second and third operands have pointer type, or one has
3368 pointer type and the other is a null pointer constant; pointer
3369 conversions (_conv.ptr_) and qualification conversions
3370 (_conv.qual_) are performed to bring them to their composite
3371 pointer type (_expr.rel_). The result is of the composite
3374 --The second and third operands have pointer to member type, or
3375 one has pointer to member type and the other is a null pointer
3376 constant; pointer to member conversions (_conv.mem_) and
3377 qualification conversions (_conv.qual_) are performed to bring
3378 them to a common type, whose cv-qualification shall match the
3379 cv-qualification of either the second or the third operand.
3380 The result is of the common type. */
3381 else if ((null_ptr_cst_p (arg2)
3382 && (TYPE_PTR_P (arg3_type) || TYPE_PTRMEM_P (arg3_type)
3383 || TYPE_PTRMEMFUNC_P (arg3_type)))
3384 || (null_ptr_cst_p (arg3)
3385 && (TYPE_PTR_P (arg2_type) || TYPE_PTRMEM_P (arg2_type)
3386 || TYPE_PTRMEMFUNC_P (arg2_type)))
3387 || (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
3388 || (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
3389 || (TYPE_PTRMEMFUNC_P (arg2_type)
3390 && TYPE_PTRMEMFUNC_P (arg3_type)))
3392 result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
3393 arg3, "conditional expression");
3394 arg2 = perform_implicit_conversion (result_type, arg2);
3395 arg3 = perform_implicit_conversion (result_type, arg3);
3400 error ("operands to ?: have different types");
3401 return error_mark_node;
3405 result = fold (build (COND_EXPR, result_type, arg1, arg2, arg3));
3406 /* We can't use result_type below, as fold might have returned a
3409 /* Expand both sides into the same slot, hopefully the target of the
3410 ?: expression. We used to check for TARGET_EXPRs here, but now we
3411 sometimes wrap them in NOP_EXPRs so the test would fail. */
3412 if (!lvalue_p && IS_AGGR_TYPE (TREE_TYPE (result)))
3413 result = get_target_expr (result);
3415 /* If this expression is an rvalue, but might be mistaken for an
3416 lvalue, we must add a NON_LVALUE_EXPR. */
3417 if (!lvalue_p && real_lvalue_p (result))
3418 result = build1 (NON_LVALUE_EXPR, TREE_TYPE (result), result);
3423 /* OPERAND is an operand to an expression. Perform necessary steps
3424 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
3428 prep_operand (tree operand)
3432 operand = convert_from_reference (operand);
3433 if (CLASS_TYPE_P (TREE_TYPE (operand))
3434 && CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (operand)))
3435 /* Make sure the template type is instantiated now. */
3436 instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (operand)));
3442 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
3443 OVERLOAD) to the CANDIDATES, returning an updated list of
3444 CANDIDATES. The ARGS are the arguments provided to the call,
3445 without any implicit object parameter. The EXPLICIT_TARGS are
3446 explicit template arguments provided. TEMPLATE_ONLY is true if
3447 only template fucntions should be considered. CONVERSION_PATH,
3448 ACCESS_PATH, and FLAGS are as for add_function_candidate. */
3451 add_candidates (tree fns, tree args,
3452 tree explicit_targs, bool template_only,
3453 tree conversion_path, tree access_path,
3455 struct z_candidate **candidates)
3458 tree non_static_args;
3460 ctype = conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE;
3461 /* Delay creating the implicit this parameter until it is needed. */
3462 non_static_args = NULL_TREE;
3469 fn = OVL_CURRENT (fns);
3470 /* Figure out which set of arguments to use. */
3471 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
3473 /* If this function is a non-static member, prepend the implicit
3474 object parameter. */
3475 if (!non_static_args)
3476 non_static_args = tree_cons (NULL_TREE,
3477 build_this (TREE_VALUE (args)),
3479 fn_args = non_static_args;
3482 /* Otherwise, just use the list of arguments provided. */
3485 if (TREE_CODE (fn) == TEMPLATE_DECL)
3486 add_template_candidate (candidates,
3496 else if (!template_only)
3497 add_function_candidate (candidates,
3504 fns = OVL_NEXT (fns);
3509 build_new_op (enum tree_code code, int flags, tree arg1, tree arg2, tree arg3)
3511 struct z_candidate *candidates = 0, *cand;
3512 tree arglist, fnname;
3514 enum tree_code code2 = NOP_EXPR;
3519 if (error_operand_p (arg1)
3520 || error_operand_p (arg2)
3521 || error_operand_p (arg3))
3522 return error_mark_node;
3524 if (code == MODIFY_EXPR)
3526 code2 = TREE_CODE (arg3);
3528 fnname = ansi_assopname (code2);
3531 fnname = ansi_opname (code);
3533 arg1 = prep_operand (arg1);
3539 case VEC_DELETE_EXPR:
3541 /* Use build_op_new_call and build_op_delete_call instead. */
3545 return build_object_call (arg1, arg2);
3551 arg2 = prep_operand (arg2);
3552 arg3 = prep_operand (arg3);
3554 if (code == COND_EXPR)
3556 if (arg2 == NULL_TREE
3557 || TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
3558 || TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
3559 || (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
3560 && ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
3563 else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
3564 && (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
3567 if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
3568 arg2 = integer_zero_node;
3570 arglist = NULL_TREE;
3572 arglist = tree_cons (NULL_TREE, arg3, arglist);
3574 arglist = tree_cons (NULL_TREE, arg2, arglist);
3575 arglist = tree_cons (NULL_TREE, arg1, arglist);
3577 /* Add namespace-scope operators to the list of functions to
3579 add_candidates (lookup_function_nonclass (fnname, arglist),
3580 arglist, NULL_TREE, false, NULL_TREE, NULL_TREE,
3581 flags, &candidates);
3582 /* Add class-member operators to the candidate set. */
3583 if (CLASS_TYPE_P (TREE_TYPE (arg1)))
3587 fns = lookup_fnfields (TYPE_BINFO (TREE_TYPE (arg1)), fnname, 1);
3588 if (fns == error_mark_node)
3591 add_candidates (BASELINK_FUNCTIONS (fns), arglist,
3593 BASELINK_BINFO (fns),
3594 TYPE_BINFO (TREE_TYPE (arg1)),
3595 flags, &candidates);
3598 /* Rearrange the arguments for ?: so that add_builtin_candidate only has
3599 to know about two args; a builtin candidate will always have a first
3600 parameter of type bool. We'll handle that in
3601 build_builtin_candidate. */
3602 if (code == COND_EXPR)
3612 args[2] = NULL_TREE;
3615 add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
3621 /* For these, the built-in candidates set is empty
3622 [over.match.oper]/3. We don't want non-strict matches
3623 because exact matches are always possible with built-in
3624 operators. The built-in candidate set for COMPONENT_REF
3625 would be empty too, but since there are no such built-in
3626 operators, we accept non-strict matches for them. */
3631 strict_p = pedantic;
3635 candidates = splice_viable (candidates, strict_p, &any_viable_p);
3640 case POSTINCREMENT_EXPR:
3641 case POSTDECREMENT_EXPR:
3642 /* Look for an `operator++ (int)'. If they didn't have
3643 one, then we fall back to the old way of doing things. */
3644 if (flags & LOOKUP_COMPLAIN)
3645 pedwarn ("no `%D(int)' declared for postfix `%s', trying prefix operator instead",
3647 operator_name_info[code].name);
3648 if (code == POSTINCREMENT_EXPR)
3649 code = PREINCREMENT_EXPR;
3651 code = PREDECREMENT_EXPR;
3652 return build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE);
3654 /* The caller will deal with these. */
3663 if (flags & LOOKUP_COMPLAIN)
3665 op_error (code, code2, arg1, arg2, arg3, "no match");
3666 print_z_candidates (candidates);
3668 return error_mark_node;
3671 cand = tourney (candidates);
3674 if (flags & LOOKUP_COMPLAIN)
3676 op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
3677 print_z_candidates (candidates);
3679 return error_mark_node;
3682 if (TREE_CODE (cand->fn) == FUNCTION_DECL)
3685 && fnname == ansi_assopname (NOP_EXPR)
3686 && DECL_ARTIFICIAL (cand->fn)
3688 && ! candidates->next->next)
3690 warning ("using synthesized `%#D' for copy assignment",
3692 cp_warning_at (" where cfront would use `%#D'",
3694 ? candidates->next->fn
3698 return build_over_call (cand, LOOKUP_NORMAL);
3701 /* Check for comparison of different enum types. */
3710 if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
3711 && TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
3712 && (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
3713 != TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
3715 warning ("comparison between `%#T' and `%#T'",
3716 TREE_TYPE (arg1), TREE_TYPE (arg2));
3723 /* We need to strip any leading REF_BIND so that bitfields don't cause
3724 errors. This should not remove any important conversions, because
3725 builtins don't apply to class objects directly. */
3726 conv = TREE_VEC_ELT (cand->convs, 0);
3727 if (TREE_CODE (conv) == REF_BIND)
3728 conv = TREE_OPERAND (conv, 0);
3729 arg1 = convert_like (conv, arg1);
3732 conv = TREE_VEC_ELT (cand->convs, 1);
3733 if (TREE_CODE (conv) == REF_BIND)
3734 conv = TREE_OPERAND (conv, 0);
3735 arg2 = convert_like (conv, arg2);
3739 conv = TREE_VEC_ELT (cand->convs, 2);
3740 if (TREE_CODE (conv) == REF_BIND)
3741 conv = TREE_OPERAND (conv, 0);
3742 arg3 = convert_like (conv, arg3);
3749 return build_modify_expr (arg1, code2, arg2);
3752 return build_indirect_ref (arg1, "unary *");
3757 case TRUNC_DIV_EXPR:
3768 case TRUNC_MOD_EXPR:
3772 case TRUTH_ANDIF_EXPR:
3773 case TRUTH_ORIF_EXPR:
3774 return cp_build_binary_op (code, arg1, arg2);
3779 case TRUTH_NOT_EXPR:
3780 case PREINCREMENT_EXPR:
3781 case POSTINCREMENT_EXPR:
3782 case PREDECREMENT_EXPR:
3783 case POSTDECREMENT_EXPR:
3786 return build_unary_op (code, arg1, candidates != 0);
3789 return build_array_ref (arg1, arg2);
3792 return build_conditional_expr (arg1, arg2, arg3);
3795 return build_m_component_ref
3796 (build_indirect_ref (arg1, NULL), arg2);
3798 /* The caller will deal with these. */
3810 /* Build a call to operator delete. This has to be handled very specially,
3811 because the restrictions on what signatures match are different from all
3812 other call instances. For a normal delete, only a delete taking (void *)
3813 or (void *, size_t) is accepted. For a placement delete, only an exact
3814 match with the placement new is accepted.
3816 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
3817 ADDR is the pointer to be deleted.
3818 SIZE is the size of the memory block to be deleted.
3819 FLAGS are the usual overloading flags.
3820 PLACEMENT is the corresponding placement new call, or NULL_TREE. */
3823 build_op_delete_call (enum tree_code code, tree addr, tree size,
3824 int flags, tree placement)
3826 tree fn = NULL_TREE;
3827 tree fns, fnname, argtypes, args, type;
3830 if (addr == error_mark_node)
3831 return error_mark_node;
3833 type = strip_array_types (TREE_TYPE (TREE_TYPE (addr)));
3835 fnname = ansi_opname (code);
3837 if (IS_AGGR_TYPE (type) && ! (flags & LOOKUP_GLOBAL))
3840 If the result of the lookup is ambiguous or inaccessible, or if
3841 the lookup selects a placement deallocation function, the
3842 program is ill-formed.
3844 Therefore, we ask lookup_fnfields to complain ambout ambiguity. */
3846 fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
3847 if (fns == error_mark_node)
3848 return error_mark_node;
3853 if (fns == NULL_TREE)
3854 fns = lookup_name_nonclass (fnname);
3861 /* Find the allocation function that is being called. */
3862 call_expr = placement;
3863 /* Sometimes we have a COMPOUND_EXPR, rather than a simple
3865 while (TREE_CODE (call_expr) == COMPOUND_EXPR)
3866 call_expr = TREE_OPERAND (call_expr, 1);
3867 /* Extract the function. */
3868 alloc_fn = get_callee_fndecl (call_expr);
3869 my_friendly_assert (alloc_fn != NULL_TREE, 20020327);
3870 /* Then the second parm type. */
3871 argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
3872 /* Also the second argument. */
3873 args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
3877 /* First try it without the size argument. */
3878 argtypes = void_list_node;
3882 /* Strip const and volatile from addr. */
3883 addr = cp_convert (ptr_type_node, addr);
3885 /* We make two tries at finding a matching `operator delete'. On
3886 the first pass, we look for a one-operator (or placement)
3887 operator delete. If we're not doing placement delete, then on
3888 the second pass we look for a two-argument delete. */
3889 for (pass = 0; pass < (placement ? 1 : 2); ++pass)
3891 /* Go through the `operator delete' functions looking for one
3892 with a matching type. */
3893 for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
3899 /* The first argument must be "void *". */
3900 t = TYPE_ARG_TYPES (TREE_TYPE (OVL_CURRENT (fn)));
3901 if (!same_type_p (TREE_VALUE (t), ptr_type_node))
3904 /* On the first pass, check the rest of the arguments. */
3907 while (argtypes && t)
3909 if (!same_type_p (TREE_VALUE (argtypes),
3912 argtypes = TREE_CHAIN (argtypes);
3915 if (!argtypes && !t)
3918 /* On the second pass, the second argument must be
3921 && same_type_p (TREE_VALUE (t), sizetype)
3922 && TREE_CHAIN (t) == void_list_node)
3926 /* If we found a match, we're done. */
3931 /* If we have a matching function, call it. */
3934 /* Make sure we have the actual function, and not an
3936 fn = OVL_CURRENT (fn);
3938 /* If the FN is a member function, make sure that it is
3940 if (DECL_CLASS_SCOPE_P (fn))
3941 perform_or_defer_access_check (TYPE_BINFO (type), fn);
3944 args = tree_cons (NULL_TREE, addr, args);
3946 args = tree_cons (NULL_TREE, addr,
3947 build_tree_list (NULL_TREE, size));
3949 return build_function_call (fn, args);
3952 /* If we are doing placement delete we do nothing if we don't find a
3953 matching op delete. */
3957 error ("no suitable `operator %s' for `%T'",
3958 operator_name_info[(int)code].name, type);
3959 return error_mark_node;
3962 /* If the current scope isn't allowed to access DECL along
3963 BASETYPE_PATH, give an error. The most derived class in
3964 BASETYPE_PATH is the one used to qualify DECL. */
3967 enforce_access (tree basetype_path, tree decl)
3969 my_friendly_assert (TREE_CODE (basetype_path) == TREE_VEC, 20030624);
3971 if (!accessible_p (basetype_path, decl))
3973 if (TREE_PRIVATE (decl))
3974 cp_error_at ("`%+#D' is private", decl);
3975 else if (TREE_PROTECTED (decl))
3976 cp_error_at ("`%+#D' is protected", decl);
3978 cp_error_at ("`%+#D' is inaccessible", decl);
3979 error ("within this context");
3986 /* Perform the conversions in CONVS on the expression EXPR. FN and
3987 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
3988 indicates the `this' argument of a method. INNER is nonzero when
3989 being called to continue a conversion chain. It is negative when a
3990 reference binding will be applied, positive otherwise. If
3991 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
3992 conversions will be emitted if appropriate. */
3995 convert_like_real (tree convs, tree expr, tree fn, int argnum, int inner,
3996 bool issue_conversion_warnings)
4000 tree totype = TREE_TYPE (convs);
4002 if (ICS_BAD_FLAG (convs)
4003 && TREE_CODE (convs) != USER_CONV
4004 && TREE_CODE (convs) != AMBIG_CONV
4005 && TREE_CODE (convs) != REF_BIND)
4008 for (; t; t = TREE_OPERAND (t, 0))
4010 if (TREE_CODE (t) == USER_CONV || !ICS_BAD_FLAG (t))
4012 expr = convert_like_real (t, expr, fn, argnum, 1,
4013 /*issue_conversion_warnings=*/false);
4016 else if (TREE_CODE (t) == AMBIG_CONV)
4017 return convert_like_real (t, expr, fn, argnum, 1,
4018 /*issue_conversion_warnings=*/false);
4019 else if (TREE_CODE (t) == IDENTITY_CONV)
4022 pedwarn ("invalid conversion from `%T' to `%T'", TREE_TYPE (expr), totype);
4024 pedwarn (" initializing argument %P of `%D'", argnum, fn);
4025 return cp_convert (totype, expr);
4028 if (issue_conversion_warnings)
4029 expr = dubious_conversion_warnings
4030 (totype, expr, "argument", fn, argnum);
4031 switch (TREE_CODE (convs))
4035 struct z_candidate *cand = USER_CONV_CAND (convs);
4036 tree convfn = cand->fn;
4039 if (DECL_CONSTRUCTOR_P (convfn))
4041 tree t = build_int_2 (0, 0);
4042 TREE_TYPE (t) = build_pointer_type (DECL_CONTEXT (convfn));
4044 args = build_tree_list (NULL_TREE, expr);
4045 if (DECL_HAS_IN_CHARGE_PARM_P (convfn)
4046 || DECL_HAS_VTT_PARM_P (convfn))
4047 /* We should never try to call the abstract or base constructor
4050 args = tree_cons (NULL_TREE, t, args);
4053 args = build_this (expr);
4054 expr = build_over_call (cand, LOOKUP_NORMAL);
4056 /* If this is a constructor or a function returning an aggr type,
4057 we need to build up a TARGET_EXPR. */
4058 if (DECL_CONSTRUCTOR_P (convfn))
4059 expr = build_cplus_new (totype, expr);
4061 /* The result of the call is then used to direct-initialize the object
4062 that is the destination of the copy-initialization. [dcl.init]
4064 Note that this step is not reflected in the conversion sequence;
4065 it affects the semantics when we actually perform the
4066 conversion, but is not considered during overload resolution.
4068 If the target is a class, that means call a ctor. */
4069 if (IS_AGGR_TYPE (totype)
4070 && (inner >= 0 || !lvalue_p (expr)))
4072 savew = warningcount, savee = errorcount;
4073 expr = build_special_member_call
4074 (NULL_TREE, complete_ctor_identifier,
4075 build_tree_list (NULL_TREE, expr), TYPE_BINFO (totype),
4076 /* Core issue 84, now a DR, says that we don't allow UDCs
4077 for these args (which deliberately breaks copy-init of an
4078 auto_ptr<Base> from an auto_ptr<Derived>). */
4079 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION);
4081 /* Tell the user where this failing constructor call came from. */
4084 if (warningcount > savew)
4086 (" initializing argument %P of `%D' from result of `%D'",
4087 argnum, fn, convfn);
4088 else if (errorcount > savee)
4090 (" initializing argument %P of `%D' from result of `%D'",
4091 argnum, fn, convfn);
4095 if (warningcount > savew)
4096 warning (" initializing temporary from result of `%D'",
4098 else if (errorcount > savee)
4099 error (" initializing temporary from result of `%D'",
4102 expr = build_cplus_new (totype, expr);
4107 if (type_unknown_p (expr))
4108 expr = instantiate_type (totype, expr, tf_error | tf_warning);
4109 /* Convert a non-array constant variable to its underlying value, unless we
4110 are about to bind it to a reference, in which case we need to
4111 leave it as an lvalue. */
4113 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
4114 expr = decl_constant_value (expr);
4117 /* Call build_user_type_conversion again for the error. */
4118 return build_user_type_conversion
4119 (totype, TREE_OPERAND (convs, 0), LOOKUP_NORMAL);
4125 expr = convert_like_real (TREE_OPERAND (convs, 0), expr, fn, argnum,
4126 TREE_CODE (convs) == REF_BIND ? -1 : 1,
4127 /*issue_conversion_warnings=*/false);
4128 if (expr == error_mark_node)
4129 return error_mark_node;
4131 switch (TREE_CODE (convs))
4134 if (! IS_AGGR_TYPE (totype))
4136 /* else fall through */
4138 if (TREE_CODE (convs) == BASE_CONV && !NEED_TEMPORARY_P (convs))
4140 /* We are going to bind a reference directly to a base-class
4141 subobject of EXPR. */
4142 tree base_ptr = build_pointer_type (totype);
4144 /* Build an expression for `*((base*) &expr)'. */
4145 expr = build_unary_op (ADDR_EXPR, expr, 0);
4146 expr = perform_implicit_conversion (base_ptr, expr);
4147 expr = build_indirect_ref (expr, "implicit conversion");
4151 /* Copy-initialization where the cv-unqualified version of the source
4152 type is the same class as, or a derived class of, the class of the
4153 destination [is treated as direct-initialization]. [dcl.init] */
4154 savew = warningcount, savee = errorcount;
4155 expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
4156 build_tree_list (NULL_TREE, expr),
4157 TYPE_BINFO (totype),
4158 LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING);
4161 if (warningcount > savew)
4162 warning (" initializing argument %P of `%D'", argnum, fn);
4163 else if (errorcount > savee)
4164 error (" initializing argument %P of `%D'", argnum, fn);
4166 return build_cplus_new (totype, expr);
4170 tree ref_type = totype;
4172 /* If necessary, create a temporary. */
4173 if (NEED_TEMPORARY_P (convs) || !non_cast_lvalue_p (expr))
4175 tree type = TREE_TYPE (TREE_OPERAND (convs, 0));
4176 expr = build_target_expr_with_type (expr, type);
4179 /* Take the address of the thing to which we will bind the
4181 expr = build_unary_op (ADDR_EXPR, expr, 1);
4182 if (expr == error_mark_node)
4183 return error_mark_node;
4185 /* Convert it to a pointer to the type referred to by the
4186 reference. This will adjust the pointer if a derived to
4187 base conversion is being performed. */
4188 expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
4190 /* Convert the pointer to the desired reference type. */
4191 return build_nop (ref_type, expr);
4195 return decay_conversion (expr);
4198 /* Warn about deprecated conversion if appropriate. */
4199 string_conv_p (totype, expr, 1);
4205 return ocp_convert (totype, expr, CONV_IMPLICIT,
4206 LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
4209 /* Build a call to __builtin_trap which can be used in an expression. */
4212 call_builtin_trap (void)
4214 tree fn = get_identifier ("__builtin_trap");
4215 if (IDENTIFIER_GLOBAL_VALUE (fn))
4216 fn = IDENTIFIER_GLOBAL_VALUE (fn);
4220 fn = build_call (fn, NULL_TREE);
4221 fn = build (COMPOUND_EXPR, integer_type_node, fn, integer_zero_node);
4225 /* ARG is being passed to a varargs function. Perform any conversions
4226 required. Return the converted value. */
4229 convert_arg_to_ellipsis (tree arg)
4233 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
4234 standard conversions are performed. */
4235 arg = decay_conversion (arg);
4238 If the argument has integral or enumeration type that is subject
4239 to the integral promotions (_conv.prom_), or a floating point
4240 type that is subject to the floating point promotion
4241 (_conv.fpprom_), the value of the argument is converted to the
4242 promoted type before the call. */
4243 if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
4244 && (TYPE_PRECISION (TREE_TYPE (arg))
4245 < TYPE_PRECISION (double_type_node)))
4246 arg = cp_convert (double_type_node, arg);
4247 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (arg)))
4248 arg = perform_integral_promotions (arg);
4250 arg = require_complete_type (arg);
4252 if (arg != error_mark_node && ! pod_type_p (TREE_TYPE (arg)))
4254 /* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
4255 here and do a bitwise copy, but now cp_expr_size will abort if we
4257 warning ("cannot pass objects of non-POD type `%#T' through `...'; \
4258 call will abort at runtime",
4260 arg = call_builtin_trap ();
4266 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
4269 build_x_va_arg (tree expr, tree type)
4271 if (processing_template_decl)
4272 return build_min (VA_ARG_EXPR, type, expr);
4274 type = complete_type_or_else (type, NULL_TREE);
4276 if (expr == error_mark_node || !type)
4277 return error_mark_node;
4279 if (! pod_type_p (type))
4281 /* Undefined behavior [expr.call] 5.2.2/7. */
4282 warning ("cannot receive objects of non-POD type `%#T' through `...'",
4286 return build_va_arg (expr, type);
4289 /* TYPE has been given to va_arg. Apply the default conversions which
4290 would have happened when passed via ellipsis. Return the promoted
4291 type, or the passed type if there is no change. */
4294 cxx_type_promotes_to (tree type)
4298 if (TREE_CODE (type) == ARRAY_TYPE)
4299 return build_pointer_type (TREE_TYPE (type));
4301 if (TREE_CODE (type) == FUNCTION_TYPE)
4302 return build_pointer_type (type);
4304 promote = type_promotes_to (type);
4305 if (same_type_p (type, promote))
4311 /* ARG is a default argument expression being passed to a parameter of
4312 the indicated TYPE, which is a parameter to FN. Do any required
4313 conversions. Return the converted value. */
4316 convert_default_arg (tree type, tree arg, tree fn, int parmnum)
4318 /* If the ARG is an unparsed default argument expression, the
4319 conversion cannot be performed. */
4320 if (TREE_CODE (arg) == DEFAULT_ARG)
4322 error ("the default argument for parameter %d of `%D' has "
4323 "not yet been parsed",
4325 return error_mark_node;
4328 if (fn && DECL_TEMPLATE_INFO (fn))
4329 arg = tsubst_default_argument (fn, type, arg);
4331 arg = break_out_target_exprs (arg);
4333 if (TREE_CODE (arg) == CONSTRUCTOR)
4335 arg = digest_init (type, arg, 0);
4336 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4337 "default argument", fn, parmnum);
4341 /* This could get clobbered by the following call. */
4342 if (TREE_HAS_CONSTRUCTOR (arg))
4343 arg = copy_node (arg);
4345 arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
4346 "default argument", fn, parmnum);
4347 arg = convert_for_arg_passing (type, arg);
4353 /* Returns the type which will really be used for passing an argument of
4357 type_passed_as (tree type)
4359 /* Pass classes with copy ctors by invisible reference. */
4360 if (TREE_ADDRESSABLE (type))
4361 type = build_reference_type (type);
4362 else if (PROMOTE_PROTOTYPES
4363 && INTEGRAL_TYPE_P (type)
4364 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
4365 type = integer_type_node;
4370 /* Actually perform the appropriate conversion. */
4373 convert_for_arg_passing (tree type, tree val)
4375 if (val == error_mark_node)
4377 /* Pass classes with copy ctors by invisible reference. */
4378 else if (TREE_ADDRESSABLE (type))
4379 val = build1 (ADDR_EXPR, build_reference_type (type), val);
4380 else if (PROMOTE_PROTOTYPES
4381 && INTEGRAL_TYPE_P (type)
4382 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
4383 val = perform_integral_promotions (val);
4387 /* Subroutine of the various build_*_call functions. Overload resolution
4388 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
4389 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
4390 bitmask of various LOOKUP_* flags which apply to the call itself. */
4393 build_over_call (struct z_candidate *cand, int flags)
4396 tree args = cand->args;
4397 tree convs = cand->convs;
4398 tree converted_args = NULL_TREE;
4399 tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
4400 tree conv, arg, val;
4404 /* Give any warnings we noticed during overload resolution. */
4406 for (val = cand->warnings; val; val = TREE_CHAIN (val))
4407 joust (cand, WRAPPER_ZC (TREE_VALUE (val)), 1);
4409 if (DECL_FUNCTION_MEMBER_P (fn))
4410 perform_or_defer_access_check (cand->access_path, fn);
4412 if (args && TREE_CODE (args) != TREE_LIST)
4413 args = build_tree_list (NULL_TREE, args);
4416 /* The implicit parameters to a constructor are not considered by overload
4417 resolution, and must be of the proper type. */
4418 if (DECL_CONSTRUCTOR_P (fn))
4420 converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
4421 arg = TREE_CHAIN (arg);
4422 parm = TREE_CHAIN (parm);
4423 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
4424 /* We should never try to call the abstract constructor. */
4426 if (DECL_HAS_VTT_PARM_P (fn))
4428 converted_args = tree_cons
4429 (NULL_TREE, TREE_VALUE (arg), converted_args);
4430 arg = TREE_CHAIN (arg);
4431 parm = TREE_CHAIN (parm);
4434 /* Bypass access control for 'this' parameter. */
4435 else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4437 tree parmtype = TREE_VALUE (parm);
4438 tree argtype = TREE_TYPE (TREE_VALUE (arg));
4442 if (ICS_BAD_FLAG (TREE_VEC_ELT (convs, i)))
4443 pedwarn ("passing `%T' as `this' argument of `%#D' discards qualifiers",
4444 TREE_TYPE (argtype), fn);
4446 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
4447 X is called for an object that is not of type X, or of a type
4448 derived from X, the behavior is undefined.
4450 So we can assume that anything passed as 'this' is non-null, and
4451 optimize accordingly. */
4452 my_friendly_assert (TREE_CODE (parmtype) == POINTER_TYPE, 19990811);
4453 /* Convert to the base in which the function was declared. */
4454 my_friendly_assert (cand->conversion_path != NULL_TREE, 20020730);
4455 converted_arg = build_base_path (PLUS_EXPR,
4457 cand->conversion_path,
4459 /* If fn was found by a using declaration, the conversion path
4460 will be to the derived class, not the base declaring fn. We
4461 must convert from derived to base. */
4462 base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
4463 TREE_TYPE (parmtype), ba_ignore, NULL);
4465 converted_arg = build_base_path (PLUS_EXPR, converted_arg,
4468 converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
4469 parm = TREE_CHAIN (parm);
4470 arg = TREE_CHAIN (arg);
4476 parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
4478 tree type = TREE_VALUE (parm);
4480 conv = TREE_VEC_ELT (convs, i);
4481 val = convert_like_with_context
4482 (conv, TREE_VALUE (arg), fn, i - is_method);
4484 val = convert_for_arg_passing (type, val);
4485 converted_args = tree_cons (NULL_TREE, val, converted_args);
4488 /* Default arguments */
4489 for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
4491 = tree_cons (NULL_TREE,
4492 convert_default_arg (TREE_VALUE (parm),
4493 TREE_PURPOSE (parm),
4498 for (; arg; arg = TREE_CHAIN (arg))
4500 = tree_cons (NULL_TREE,
4501 convert_arg_to_ellipsis (TREE_VALUE (arg)),
4504 converted_args = nreverse (converted_args);
4507 check_function_format (NULL, TYPE_ATTRIBUTES (TREE_TYPE (fn)),
4510 /* Avoid actually calling copy constructors and copy assignment operators,
4513 if (! flag_elide_constructors)
4514 /* Do things the hard way. */;
4515 else if (TREE_VEC_LENGTH (convs) == 1
4516 && DECL_COPY_CONSTRUCTOR_P (fn))
4519 arg = skip_artificial_parms_for (fn, converted_args);
4520 arg = TREE_VALUE (arg);
4522 /* Pull out the real argument, disregarding const-correctness. */
4524 while (TREE_CODE (targ) == NOP_EXPR
4525 || TREE_CODE (targ) == NON_LVALUE_EXPR
4526 || TREE_CODE (targ) == CONVERT_EXPR)
4527 targ = TREE_OPERAND (targ, 0);
4528 if (TREE_CODE (targ) == ADDR_EXPR)
4530 targ = TREE_OPERAND (targ, 0);
4531 if (!same_type_ignoring_top_level_qualifiers_p
4532 (TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
4541 arg = build_indirect_ref (arg, 0);
4543 /* [class.copy]: the copy constructor is implicitly defined even if
4544 the implementation elided its use. */
4545 if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
4548 /* If we're creating a temp and we already have one, don't create a
4549 new one. If we're not creating a temp but we get one, use
4550 INIT_EXPR to collapse the temp into our target. Otherwise, if the
4551 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
4552 temp or an INIT_EXPR otherwise. */
4553 if (integer_zerop (TREE_VALUE (args)))
4555 if (TREE_CODE (arg) == TARGET_EXPR)
4557 else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4558 return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
4560 else if (TREE_CODE (arg) == TARGET_EXPR
4561 || TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
4564 tree to = stabilize_reference
4565 (build_indirect_ref (TREE_VALUE (args), 0));
4567 val = build (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
4568 address = build_unary_op (ADDR_EXPR, val, 0);
4569 /* Avoid a warning about this expression, if the address is
4571 TREE_USED (address) = 1;
4575 else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
4577 && TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
4579 tree to = stabilize_reference
4580 (build_indirect_ref (TREE_VALUE (converted_args), 0));
4582 arg = build_indirect_ref (TREE_VALUE (TREE_CHAIN (converted_args)), 0);
4583 val = build (MODIFY_EXPR, TREE_TYPE (to), to, arg);
4589 if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
4591 tree t, *p = &TREE_VALUE (converted_args);
4592 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
4595 my_friendly_assert (binfo && binfo != error_mark_node, 20010730);
4597 *p = build_base_path (PLUS_EXPR, *p, binfo, 1);
4598 if (TREE_SIDE_EFFECTS (*p))
4599 *p = save_expr (*p);
4600 t = build_pointer_type (TREE_TYPE (fn));
4601 if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
4602 fn = build_java_interface_fn_ref (fn, *p);
4604 fn = build_vfn_ref (build_indirect_ref (*p, 0), DECL_VINDEX (fn));
4607 else if (DECL_INLINE (fn))
4608 fn = inline_conversion (fn);
4610 fn = build_addr_func (fn);
4612 return build_cxx_call (fn, args, converted_args);
4615 /* Build and return a call to FN, using the the CONVERTED_ARGS. ARGS
4616 gives the original form of the arguments. This function performs
4617 no overload resolution, conversion, or other high-level
4621 build_cxx_call(tree fn, tree args, tree converted_args)
4625 /* Recognize certain built-in functions so we can make tree-codes
4626 other than CALL_EXPR. We do this when it enables fold-const.c
4627 to do something useful. */
4628 if (TREE_CODE (fn) == ADDR_EXPR
4629 && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL
4630 && DECL_BUILT_IN (TREE_OPERAND (fn, 0)))
4633 exp = expand_tree_builtin (TREE_OPERAND (fn, 0), args, converted_args);
4638 fn = build_call (fn, converted_args);
4640 /* If this call might throw an exception, note that fact. */
4641 fndecl = get_callee_fndecl (fn);
4642 if ((!fndecl || !TREE_NOTHROW (fndecl))
4643 && at_function_scope_p ()
4645 cp_function_chain->can_throw = 1;
4647 /* Some built-in function calls will be evaluated at compile-time in
4651 if (VOID_TYPE_P (TREE_TYPE (fn)))
4654 fn = require_complete_type (fn);
4655 if (fn == error_mark_node)
4656 return error_mark_node;
4658 if (IS_AGGR_TYPE (TREE_TYPE (fn)))
4659 fn = build_cplus_new (TREE_TYPE (fn), fn);
4660 return convert_from_reference (fn);
4663 static GTY(()) tree java_iface_lookup_fn;
4665 /* Make an expression which yields the address of the Java interface
4666 method FN. This is achieved by generating a call to libjava's
4667 _Jv_LookupInterfaceMethodIdx(). */
4670 build_java_interface_fn_ref (tree fn, tree instance)
4672 tree lookup_args, lookup_fn, method, idx;
4673 tree klass_ref, iface, iface_ref;
4676 if (!java_iface_lookup_fn)
4678 tree endlink = build_void_list_node ();
4679 tree t = tree_cons (NULL_TREE, ptr_type_node,
4680 tree_cons (NULL_TREE, ptr_type_node,
4681 tree_cons (NULL_TREE, java_int_type_node,
4683 java_iface_lookup_fn
4684 = builtin_function ("_Jv_LookupInterfaceMethodIdx",
4685 build_function_type (ptr_type_node, t),
4686 0, NOT_BUILT_IN, NULL, NULL_TREE);
4689 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
4690 This is the first entry in the vtable. */
4691 klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
4694 /* Get the java.lang.Class pointer for the interface being called. */
4695 iface = DECL_CONTEXT (fn);
4696 iface_ref = lookup_field (iface, get_identifier ("class$"), 0, false);
4697 if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
4698 || DECL_CONTEXT (iface_ref) != iface)
4700 error ("could not find class$ field in java interface type `%T'",
4702 return error_mark_node;
4704 iface_ref = build1 (ADDR_EXPR, build_pointer_type (iface), iface_ref);
4706 /* Determine the itable index of FN. */
4708 for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
4710 if (!DECL_VIRTUAL_P (method))
4716 idx = build_int_2 (i, 0);
4718 lookup_args = tree_cons (NULL_TREE, klass_ref,
4719 tree_cons (NULL_TREE, iface_ref,
4720 build_tree_list (NULL_TREE, idx)));
4721 lookup_fn = build1 (ADDR_EXPR,
4722 build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
4723 java_iface_lookup_fn);
4724 return build (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
4727 /* Returns the value to use for the in-charge parameter when making a
4728 call to a function with the indicated NAME. */
4731 in_charge_arg_for_name (tree name)
4733 if (name == base_ctor_identifier
4734 || name == base_dtor_identifier)
4735 return integer_zero_node;
4736 else if (name == complete_ctor_identifier)
4737 return integer_one_node;
4738 else if (name == complete_dtor_identifier)
4739 return integer_two_node;
4740 else if (name == deleting_dtor_identifier)
4741 return integer_three_node;
4743 /* This function should only be called with one of the names listed
4749 /* Build a call to a constructor, destructor, or an assignment
4750 operator for INSTANCE, an expression with class type. NAME
4751 indicates the special member function to call; ARGS are the
4752 arguments. BINFO indicates the base of INSTANCE that is to be
4753 passed as the `this' parameter to the member function called.
4755 FLAGS are the LOOKUP_* flags to use when processing the call.
4757 If NAME indicates a complete object constructor, INSTANCE may be
4758 NULL_TREE. In this case, the caller will call build_cplus_new to
4759 store the newly constructed object into a VAR_DECL. */
4762 build_special_member_call (tree instance, tree name, tree args,
4763 tree binfo, int flags)
4766 /* The type of the subobject to be constructed or destroyed. */
4769 my_friendly_assert (name == complete_ctor_identifier
4770 || name == base_ctor_identifier
4771 || name == complete_dtor_identifier
4772 || name == base_dtor_identifier
4773 || name == deleting_dtor_identifier
4774 || name == ansi_assopname (NOP_EXPR),
4776 my_friendly_assert (binfo != NULL_TREE, 20020712);
4778 class_type = BINFO_TYPE (binfo);
4780 /* Handle the special case where INSTANCE is NULL_TREE. */
4781 if (name == complete_ctor_identifier && !instance)
4783 instance = build_int_2 (0, 0);
4784 TREE_TYPE (instance) = build_pointer_type (class_type);
4785 instance = build1 (INDIRECT_REF, class_type, instance);
4787 else if (name == complete_dtor_identifier
4788 || name == base_dtor_identifier
4789 || name == deleting_dtor_identifier)
4790 my_friendly_assert (args == NULL_TREE, 20020712);
4792 my_friendly_assert (instance != NULL_TREE, 20020712);
4794 /* Resolve the name. */
4795 if (!complete_type_or_else (BINFO_TYPE (binfo), NULL_TREE))
4796 return error_mark_node;
4798 fns = lookup_fnfields (binfo, name, 1);
4800 /* When making a call to a constructor or destructor for a subobject
4801 that uses virtual base classes, pass down a pointer to a VTT for
4803 if ((name == base_ctor_identifier
4804 || name == base_dtor_identifier)
4805 && TYPE_USES_VIRTUAL_BASECLASSES (class_type))
4810 /* If the current function is a complete object constructor
4811 or destructor, then we fetch the VTT directly.
4812 Otherwise, we look it up using the VTT we were given. */
4813 vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
4814 vtt = decay_conversion (vtt);
4815 vtt = build (COND_EXPR, TREE_TYPE (vtt),
4816 build (EQ_EXPR, boolean_type_node,
4817 current_in_charge_parm, integer_zero_node),
4820 my_friendly_assert (BINFO_SUBVTT_INDEX (binfo), 20010110);
4821 sub_vtt = build (PLUS_EXPR, TREE_TYPE (vtt), vtt,
4822 BINFO_SUBVTT_INDEX (binfo));
4824 args = tree_cons (NULL_TREE, sub_vtt, args);
4827 return build_new_method_call (instance, fns, args, binfo, flags);
4830 /* Return the NAME, as a C string. The NAME indicates a function that
4831 is a member of TYPE. *FREE_P is set to true if the caller must
4832 free the memory returned.
4834 Rather than go through all of this, we should simply set the names
4835 of constructors and destructors appropriately, and dispense with
4836 ctor_identifier, dtor_identifier, etc. */
4839 name_as_c_string (tree name, tree type, bool *free_p)
4843 /* Assume that we will not allocate memory. */
4845 /* Constructors and destructors are special. */
4846 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
4849 = (char *) IDENTIFIER_POINTER (constructor_name (type));
4850 /* For a destructor, add the '~'. */
4851 if (name == complete_dtor_identifier
4852 || name == base_dtor_identifier
4853 || name == deleting_dtor_identifier)
4855 pretty_name = concat ("~", pretty_name, NULL);
4856 /* Remember that we need to free the memory allocated. */
4861 pretty_name = (char *) IDENTIFIER_POINTER (name);
4866 /* Build a call to "INSTANCE.FN (ARGS)". */
4869 build_new_method_call (tree instance, tree fns, tree args,
4870 tree conversion_path, int flags)
4872 struct z_candidate *candidates = 0, *cand;
4873 tree explicit_targs = NULL_TREE;
4874 tree basetype = NULL_TREE;
4877 tree mem_args = NULL_TREE, instance_ptr;
4883 int template_only = 0;
4889 my_friendly_assert (instance != NULL_TREE, 20020729);
4891 if (error_operand_p (instance)
4892 || error_operand_p (fns)
4893 || args == error_mark_node)
4894 return error_mark_node;
4896 orig_instance = instance;
4900 if (processing_template_decl)
4902 instance = build_non_dependent_expr (instance);
4903 if (!BASELINK_P (fns)
4904 && TREE_CODE (fns) != PSEUDO_DTOR_EXPR
4905 && TREE_TYPE (fns) != unknown_type_node)
4906 fns = build_non_dependent_expr (fns);
4907 args = build_non_dependent_args (orig_args);
4910 /* Process the argument list. */
4912 args = resolve_args (args);
4913 if (args == error_mark_node)
4914 return error_mark_node;
4916 if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
4917 instance = convert_from_reference (instance);
4918 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
4919 instance_ptr = build_this (instance);
4921 if (!BASELINK_P (fns))
4923 call = build_field_call (instance_ptr, fns, args);
4926 error ("call to non-function `%D'", fns);
4927 return error_mark_node;
4930 if (!conversion_path)
4931 conversion_path = BASELINK_BINFO (fns);
4932 access_binfo = BASELINK_ACCESS_BINFO (fns);
4933 optype = BASELINK_OPTYPE (fns);
4934 fns = BASELINK_FUNCTIONS (fns);
4936 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
4938 explicit_targs = TREE_OPERAND (fns, 1);
4939 fns = TREE_OPERAND (fns, 0);
4943 my_friendly_assert (TREE_CODE (fns) == FUNCTION_DECL
4944 || TREE_CODE (fns) == TEMPLATE_DECL
4945 || TREE_CODE (fns) == OVERLOAD,
4948 /* XXX this should be handled before we get here. */
4949 if (! IS_AGGR_TYPE (basetype))
4951 if ((flags & LOOKUP_COMPLAIN) && basetype != error_mark_node)
4952 error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
4953 fns, instance, basetype);
4955 return error_mark_node;
4958 fn = get_first_fn (fns);
4959 name = DECL_NAME (fn);
4961 if (IDENTIFIER_CTOR_OR_DTOR_P (name))
4963 /* Callers should explicitly indicate whether they want to construct
4964 the complete object or just the part without virtual bases. */
4965 my_friendly_assert (name != ctor_identifier, 20000408);
4966 /* Similarly for destructors. */
4967 my_friendly_assert (name != dtor_identifier, 20000408);
4970 /* It's OK to call destructors on cv-qualified objects. Therefore,
4971 convert the INSTANCE_PTR to the unqualified type, if necessary. */
4972 if (DECL_DESTRUCTOR_P (fn))
4974 tree type = build_pointer_type (basetype);
4975 if (!same_type_p (type, TREE_TYPE (instance_ptr)))
4976 instance_ptr = build_nop (type, instance_ptr);
4979 class_type = (conversion_path ? BINFO_TYPE (conversion_path) : NULL_TREE);
4980 mem_args = tree_cons (NULL_TREE, instance_ptr, args);
4982 for (fn = fns; fn; fn = OVL_NEXT (fn))
4984 tree t = OVL_CURRENT (fn);
4987 /* We can end up here for copy-init of same or base class. */
4988 if ((flags & LOOKUP_ONLYCONVERTING)
4989 && DECL_NONCONVERTING_P (t))
4992 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
4993 this_arglist = mem_args;
4995 this_arglist = args;
4997 if (TREE_CODE (t) == TEMPLATE_DECL)
4998 /* A member template. */
4999 add_template_candidate (&candidates, t,
5002 this_arglist, optype,
5007 else if (! template_only)
5008 add_function_candidate (&candidates, t,
5016 candidates = splice_viable (candidates, pedantic, &any_viable_p);
5019 /* XXX will LOOKUP_SPECULATIVELY be needed when this is done? */
5020 if (flags & LOOKUP_SPECULATIVELY)
5022 if (!COMPLETE_TYPE_P (basetype))
5023 cxx_incomplete_type_error (instance_ptr, basetype);
5029 pretty_name = name_as_c_string (name, basetype, &free_p);
5030 error ("no matching function for call to `%T::%s(%A)%#V'",
5031 basetype, pretty_name, user_args,
5032 TREE_TYPE (TREE_TYPE (instance_ptr)));
5036 print_z_candidates (candidates);
5037 return error_mark_node;
5040 cand = tourney (candidates);
5046 pretty_name = name_as_c_string (name, basetype, &free_p);
5047 error ("call of overloaded `%s(%A)' is ambiguous", pretty_name,
5049 print_z_candidates (candidates);
5052 return error_mark_node;
5055 if (DECL_PURE_VIRTUAL_P (cand->fn)
5056 && instance == current_class_ref
5057 && (DECL_CONSTRUCTOR_P (current_function_decl)
5058 || DECL_DESTRUCTOR_P (current_function_decl))
5059 && ! (flags & LOOKUP_NONVIRTUAL)
5060 && value_member (cand->fn, CLASSTYPE_PURE_VIRTUALS (basetype)))
5061 error ((DECL_CONSTRUCTOR_P (current_function_decl) ?
5062 "abstract virtual `%#D' called from constructor"
5063 : "abstract virtual `%#D' called from destructor"),
5065 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
5066 && is_dummy_object (instance_ptr))
5068 error ("cannot call member function `%D' without object", cand->fn);
5069 return error_mark_node;
5072 if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
5073 && resolves_to_fixed_type_p (instance, 0))
5074 flags |= LOOKUP_NONVIRTUAL;
5076 if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE)
5077 call = build_over_call (cand, flags);
5080 call = build_over_call (cand, flags);
5081 /* In an expression of the form `a->f()' where `f' turns out to
5082 be a static member function, `a' is none-the-less evaluated. */
5083 if (!is_dummy_object (instance_ptr) && TREE_SIDE_EFFECTS (instance))
5084 call = build (COMPOUND_EXPR, TREE_TYPE (call), instance, call);
5087 if (processing_template_decl && call != error_mark_node)
5088 return build_min (CALL_EXPR,
5090 build_min_nt (COMPONENT_REF,
5097 /* Returns true iff standard conversion sequence ICS1 is a proper
5098 subsequence of ICS2. */
5101 is_subseq (tree ics1, tree ics2)
5103 /* We can assume that a conversion of the same code
5104 between the same types indicates a subsequence since we only get
5105 here if the types we are converting from are the same. */
5107 while (TREE_CODE (ics1) == RVALUE_CONV
5108 || TREE_CODE (ics1) == LVALUE_CONV)
5109 ics1 = TREE_OPERAND (ics1, 0);
5113 while (TREE_CODE (ics2) == RVALUE_CONV
5114 || TREE_CODE (ics2) == LVALUE_CONV)
5115 ics2 = TREE_OPERAND (ics2, 0);
5117 if (TREE_CODE (ics2) == USER_CONV
5118 || TREE_CODE (ics2) == AMBIG_CONV
5119 || TREE_CODE (ics2) == IDENTITY_CONV)
5120 /* At this point, ICS1 cannot be a proper subsequence of
5121 ICS2. We can get a USER_CONV when we are comparing the
5122 second standard conversion sequence of two user conversion
5126 ics2 = TREE_OPERAND (ics2, 0);
5128 if (TREE_CODE (ics2) == TREE_CODE (ics1)
5129 && same_type_p (TREE_TYPE (ics2), TREE_TYPE (ics1))
5130 && same_type_p (TREE_TYPE (TREE_OPERAND (ics2, 0)),
5131 TREE_TYPE (TREE_OPERAND (ics1, 0))))
5136 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
5137 be any _TYPE nodes. */
5140 is_properly_derived_from (tree derived, tree base)
5142 if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
5143 || !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
5146 /* We only allow proper derivation here. The DERIVED_FROM_P macro
5147 considers every class derived from itself. */
5148 return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
5149 && DERIVED_FROM_P (base, derived));
5152 /* We build the ICS for an implicit object parameter as a pointer
5153 conversion sequence. However, such a sequence should be compared
5154 as if it were a reference conversion sequence. If ICS is the
5155 implicit conversion sequence for an implicit object parameter,
5156 modify it accordingly. */
5159 maybe_handle_implicit_object (tree *ics)
5161 if (ICS_THIS_FLAG (*ics))
5163 /* [over.match.funcs]
5165 For non-static member functions, the type of the
5166 implicit object parameter is "reference to cv X"
5167 where X is the class of which the function is a
5168 member and cv is the cv-qualification on the member
5169 function declaration. */
5171 tree reference_type;
5173 /* The `this' parameter is a pointer to a class type. Make the
5174 implicit conversion talk about a reference to that same class
5176 reference_type = TREE_TYPE (TREE_TYPE (*ics));
5177 reference_type = build_reference_type (reference_type);
5179 if (TREE_CODE (t) == QUAL_CONV)
5180 t = TREE_OPERAND (t, 0);
5181 if (TREE_CODE (t) == PTR_CONV)
5182 t = TREE_OPERAND (t, 0);
5183 t = build1 (IDENTITY_CONV, TREE_TYPE (TREE_TYPE (t)), NULL_TREE);
5184 t = direct_reference_binding (reference_type, t);
5189 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
5190 and return the type to which the reference refers. Otherwise,
5191 leave *ICS unchanged and return NULL_TREE. */
5194 maybe_handle_ref_bind (tree *ics)
5196 if (TREE_CODE (*ics) == REF_BIND)
5198 tree old_ics = *ics;
5199 tree type = TREE_TYPE (TREE_TYPE (old_ics));
5200 *ics = TREE_OPERAND (old_ics, 0);
5201 ICS_USER_FLAG (*ics) = ICS_USER_FLAG (old_ics);
5202 ICS_BAD_FLAG (*ics) = ICS_BAD_FLAG (old_ics);
5209 /* Compare two implicit conversion sequences according to the rules set out in
5210 [over.ics.rank]. Return values:
5212 1: ics1 is better than ics2
5213 -1: ics2 is better than ics1
5214 0: ics1 and ics2 are indistinguishable */
5217 compare_ics (tree ics1, tree ics2)
5223 tree deref_from_type1 = NULL_TREE;
5224 tree deref_from_type2 = NULL_TREE;
5225 tree deref_to_type1 = NULL_TREE;
5226 tree deref_to_type2 = NULL_TREE;
5229 /* REF_BINDING is nonzero if the result of the conversion sequence
5230 is a reference type. In that case TARGET_TYPE is the
5231 type referred to by the reference. */
5235 /* Handle implicit object parameters. */
5236 maybe_handle_implicit_object (&ics1);
5237 maybe_handle_implicit_object (&ics2);
5239 /* Handle reference parameters. */
5240 target_type1 = maybe_handle_ref_bind (&ics1);
5241 target_type2 = maybe_handle_ref_bind (&ics2);
5245 When comparing the basic forms of implicit conversion sequences (as
5246 defined in _over.best.ics_)
5248 --a standard conversion sequence (_over.ics.scs_) is a better
5249 conversion sequence than a user-defined conversion sequence
5250 or an ellipsis conversion sequence, and
5252 --a user-defined conversion sequence (_over.ics.user_) is a
5253 better conversion sequence than an ellipsis conversion sequence
5254 (_over.ics.ellipsis_). */
5255 rank1 = ICS_RANK (ics1);
5256 rank2 = ICS_RANK (ics2);
5260 else if (rank1 < rank2)
5263 if (rank1 == BAD_RANK)
5265 /* XXX Isn't this an extension? */
5266 /* Both ICS are bad. We try to make a decision based on what
5267 would have happenned if they'd been good. */
5268 if (ICS_USER_FLAG (ics1) > ICS_USER_FLAG (ics2)
5269 || ICS_STD_RANK (ics1) > ICS_STD_RANK (ics2))
5271 else if (ICS_USER_FLAG (ics1) < ICS_USER_FLAG (ics2)
5272 || ICS_STD_RANK (ics1) < ICS_STD_RANK (ics2))
5275 /* We couldn't make up our minds; try to figure it out below. */
5278 if (ICS_ELLIPSIS_FLAG (ics1))
5279 /* Both conversions are ellipsis conversions. */
5282 /* User-defined conversion sequence U1 is a better conversion sequence
5283 than another user-defined conversion sequence U2 if they contain the
5284 same user-defined conversion operator or constructor and if the sec-
5285 ond standard conversion sequence of U1 is better than the second
5286 standard conversion sequence of U2. */
5288 if (ICS_USER_FLAG (ics1))
5292 for (t1 = ics1; TREE_CODE (t1) != USER_CONV; t1 = TREE_OPERAND (t1, 0))
5293 if (TREE_CODE (t1) == AMBIG_CONV)
5295 for (t2 = ics2; TREE_CODE (t2) != USER_CONV; t2 = TREE_OPERAND (t2, 0))
5296 if (TREE_CODE (t2) == AMBIG_CONV)
5299 if (USER_CONV_FN (t1) != USER_CONV_FN (t2))
5302 /* We can just fall through here, after setting up
5303 FROM_TYPE1 and FROM_TYPE2. */
5304 from_type1 = TREE_TYPE (t1);
5305 from_type2 = TREE_TYPE (t2);
5309 /* We're dealing with two standard conversion sequences.
5313 Standard conversion sequence S1 is a better conversion
5314 sequence than standard conversion sequence S2 if
5316 --S1 is a proper subsequence of S2 (comparing the conversion
5317 sequences in the canonical form defined by _over.ics.scs_,
5318 excluding any Lvalue Transformation; the identity
5319 conversion sequence is considered to be a subsequence of
5320 any non-identity conversion sequence */
5323 while (TREE_CODE (from_type1) != IDENTITY_CONV)
5324 from_type1 = TREE_OPERAND (from_type1, 0);
5325 from_type1 = TREE_TYPE (from_type1);
5328 while (TREE_CODE (from_type2) != IDENTITY_CONV)
5329 from_type2 = TREE_OPERAND (from_type2, 0);
5330 from_type2 = TREE_TYPE (from_type2);
5333 if (same_type_p (from_type1, from_type2))
5335 if (is_subseq (ics1, ics2))
5337 if (is_subseq (ics2, ics1))
5340 /* Otherwise, one sequence cannot be a subsequence of the other; they
5341 don't start with the same type. This can happen when comparing the
5342 second standard conversion sequence in two user-defined conversion
5349 --the rank of S1 is better than the rank of S2 (by the rules
5352 Standard conversion sequences are ordered by their ranks: an Exact
5353 Match is a better conversion than a Promotion, which is a better
5354 conversion than a Conversion.
5356 Two conversion sequences with the same rank are indistinguishable
5357 unless one of the following rules applies:
5359 --A conversion that is not a conversion of a pointer, or pointer
5360 to member, to bool is better than another conversion that is such
5363 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
5364 so that we do not have to check it explicitly. */
5365 if (ICS_STD_RANK (ics1) < ICS_STD_RANK (ics2))
5367 else if (ICS_STD_RANK (ics2) < ICS_STD_RANK (ics1))
5370 to_type1 = TREE_TYPE (ics1);
5371 to_type2 = TREE_TYPE (ics2);
5373 if (TYPE_PTR_P (from_type1)
5374 && TYPE_PTR_P (from_type2)
5375 && TYPE_PTR_P (to_type1)
5376 && TYPE_PTR_P (to_type2))
5378 deref_from_type1 = TREE_TYPE (from_type1);
5379 deref_from_type2 = TREE_TYPE (from_type2);
5380 deref_to_type1 = TREE_TYPE (to_type1);
5381 deref_to_type2 = TREE_TYPE (to_type2);
5383 /* The rules for pointers to members A::* are just like the rules
5384 for pointers A*, except opposite: if B is derived from A then
5385 A::* converts to B::*, not vice versa. For that reason, we
5386 switch the from_ and to_ variables here. */
5387 else if (TYPE_PTRMEM_P (from_type1)
5388 && TYPE_PTRMEM_P (from_type2)
5389 && TYPE_PTRMEM_P (to_type1)
5390 && TYPE_PTRMEM_P (to_type2))
5392 deref_to_type1 = TYPE_OFFSET_BASETYPE (TREE_TYPE (from_type1));
5393 deref_to_type2 = TYPE_OFFSET_BASETYPE (TREE_TYPE (from_type2));
5394 deref_from_type1 = TYPE_OFFSET_BASETYPE (TREE_TYPE (to_type1));
5395 deref_from_type2 = TYPE_OFFSET_BASETYPE (TREE_TYPE (to_type2));
5397 else if (TYPE_PTRMEMFUNC_P (from_type1)
5398 && TYPE_PTRMEMFUNC_P (from_type2)
5399 && TYPE_PTRMEMFUNC_P (to_type1)
5400 && TYPE_PTRMEMFUNC_P (to_type2))
5402 deref_to_type1 = TYPE_PTRMEMFUNC_OBJECT_TYPE (from_type1);
5403 deref_to_type2 = TYPE_PTRMEMFUNC_OBJECT_TYPE (from_type2);
5404 deref_from_type1 = TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type1);
5405 deref_from_type2 = TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type2);
5408 if (deref_from_type1 != NULL_TREE
5409 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
5410 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
5412 /* This was one of the pointer or pointer-like conversions.
5416 --If class B is derived directly or indirectly from class A,
5417 conversion of B* to A* is better than conversion of B* to
5418 void*, and conversion of A* to void* is better than
5419 conversion of B* to void*. */
5420 if (TREE_CODE (deref_to_type1) == VOID_TYPE
5421 && TREE_CODE (deref_to_type2) == VOID_TYPE)
5423 if (is_properly_derived_from (deref_from_type1,
5426 else if (is_properly_derived_from (deref_from_type2,
5430 else if (TREE_CODE (deref_to_type1) == VOID_TYPE
5431 || TREE_CODE (deref_to_type2) == VOID_TYPE)
5433 if (same_type_p (deref_from_type1, deref_from_type2))
5435 if (TREE_CODE (deref_to_type2) == VOID_TYPE)
5437 if (is_properly_derived_from (deref_from_type1,
5441 /* We know that DEREF_TO_TYPE1 is `void' here. */
5442 else if (is_properly_derived_from (deref_from_type1,
5447 else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
5448 && IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
5452 --If class B is derived directly or indirectly from class A
5453 and class C is derived directly or indirectly from B,
5455 --conversion of C* to B* is better than conversion of C* to
5458 --conversion of B* to A* is better than conversion of C* to
5460 if (same_type_p (deref_from_type1, deref_from_type2))
5462 if (is_properly_derived_from (deref_to_type1,
5465 else if (is_properly_derived_from (deref_to_type2,
5469 else if (same_type_p (deref_to_type1, deref_to_type2))
5471 if (is_properly_derived_from (deref_from_type2,
5474 else if (is_properly_derived_from (deref_from_type1,
5480 else if (CLASS_TYPE_P (non_reference (from_type1))
5481 && same_type_p (from_type1, from_type2))
5483 tree from = non_reference (from_type1);
5487 --binding of an expression of type C to a reference of type
5488 B& is better than binding an expression of type C to a
5489 reference of type A&
5491 --conversion of C to B is better than conversion of C to A, */
5492 if (is_properly_derived_from (from, to_type1)
5493 && is_properly_derived_from (from, to_type2))
5495 if (is_properly_derived_from (to_type1, to_type2))
5497 else if (is_properly_derived_from (to_type2, to_type1))
5501 else if (CLASS_TYPE_P (non_reference (to_type1))
5502 && same_type_p (to_type1, to_type2))
5504 tree to = non_reference (to_type1);
5508 --binding of an expression of type B to a reference of type
5509 A& is better than binding an expression of type C to a
5510 reference of type A&,
5512 --onversion of B to A is better than conversion of C to A */
5513 if (is_properly_derived_from (from_type1, to)
5514 && is_properly_derived_from (from_type2, to))
5516 if (is_properly_derived_from (from_type2, from_type1))
5518 else if (is_properly_derived_from (from_type1, from_type2))
5525 --S1 and S2 differ only in their qualification conversion and yield
5526 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
5527 qualification signature of type T1 is a proper subset of the cv-
5528 qualification signature of type T2 */
5529 if (TREE_CODE (ics1) == QUAL_CONV
5530 && TREE_CODE (ics2) == QUAL_CONV
5531 && same_type_p (from_type1, from_type2))
5532 return comp_cv_qual_signature (to_type1, to_type2);
5536 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
5537 types to which the references refer are the same type except for
5538 top-level cv-qualifiers, and the type to which the reference
5539 initialized by S2 refers is more cv-qualified than the type to
5540 which the reference initialized by S1 refers */
5542 if (target_type1 && target_type2
5543 && same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
5544 return comp_cv_qualification (target_type2, target_type1);
5546 /* Neither conversion sequence is better than the other. */
5550 /* The source type for this standard conversion sequence. */
5553 source_type (tree t)
5555 for (;; t = TREE_OPERAND (t, 0))
5557 if (TREE_CODE (t) == USER_CONV
5558 || TREE_CODE (t) == AMBIG_CONV
5559 || TREE_CODE (t) == IDENTITY_CONV)
5560 return TREE_TYPE (t);
5565 /* Note a warning about preferring WINNER to LOSER. We do this by storing
5566 a pointer to LOSER and re-running joust to produce the warning if WINNER
5567 is actually used. */
5570 add_warning (struct z_candidate *winner, struct z_candidate *loser)
5572 winner->warnings = tree_cons (NULL_TREE,
5573 build_zc_wrapper (loser),
5577 /* Compare two candidates for overloading as described in
5578 [over.match.best]. Return values:
5580 1: cand1 is better than cand2
5581 -1: cand2 is better than cand1
5582 0: cand1 and cand2 are indistinguishable */
5585 joust (struct z_candidate *cand1, struct z_candidate *cand2, bool warn)
5588 int i, off1 = 0, off2 = 0, len;
5590 /* Candidates that involve bad conversions are always worse than those
5592 if (cand1->viable > cand2->viable)
5594 if (cand1->viable < cand2->viable)
5597 /* If we have two pseudo-candidates for conversions to the same type,
5598 or two candidates for the same function, arbitrarily pick one. */
5599 if (cand1->fn == cand2->fn
5600 && (TYPE_P (cand1->fn) || DECL_P (cand1->fn)))
5603 /* a viable function F1
5604 is defined to be a better function than another viable function F2 if
5605 for all arguments i, ICSi(F1) is not a worse conversion sequence than
5606 ICSi(F2), and then */
5608 /* for some argument j, ICSj(F1) is a better conversion sequence than
5611 /* For comparing static and non-static member functions, we ignore
5612 the implicit object parameter of the non-static function. The
5613 standard says to pretend that the static function has an object
5614 parm, but that won't work with operator overloading. */
5615 len = TREE_VEC_LENGTH (cand1->convs);
5616 if (len != TREE_VEC_LENGTH (cand2->convs))
5618 if (DECL_STATIC_FUNCTION_P (cand1->fn)
5619 && ! DECL_STATIC_FUNCTION_P (cand2->fn))
5621 else if (! DECL_STATIC_FUNCTION_P (cand1->fn)
5622 && DECL_STATIC_FUNCTION_P (cand2->fn))
5631 for (i = 0; i < len; ++i)
5633 tree t1 = TREE_VEC_ELT (cand1->convs, i+off1);
5634 tree t2 = TREE_VEC_ELT (cand2->convs, i+off2);
5635 int comp = compare_ics (t1, t2);
5640 && ICS_RANK (t1) + ICS_RANK (t2) == STD_RANK + PROMO_RANK
5641 && TREE_CODE (t1) == STD_CONV
5642 && TREE_CODE (t2) == STD_CONV
5643 && TREE_CODE (TREE_TYPE (t1)) == INTEGER_TYPE
5644 && TREE_CODE (TREE_TYPE (t2)) == INTEGER_TYPE
5645 && (TYPE_PRECISION (TREE_TYPE (t1))
5646 == TYPE_PRECISION (TREE_TYPE (t2)))
5647 && (TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (t1, 0)))
5648 || (TREE_CODE (TREE_TYPE (TREE_OPERAND (t1, 0)))
5651 tree type = TREE_TYPE (TREE_OPERAND (t1, 0));
5653 struct z_candidate *w, *l;
5655 type1 = TREE_TYPE (t1), type2 = TREE_TYPE (t2),
5656 w = cand1, l = cand2;
5658 type1 = TREE_TYPE (t2), type2 = TREE_TYPE (t1),
5659 w = cand2, l = cand1;
5663 warning ("passing `%T' chooses `%T' over `%T'",
5664 type, type1, type2);
5665 warning (" in call to `%D'", w->fn);
5671 if (winner && comp != winner)
5680 /* warn about confusing overload resolution for user-defined conversions,
5681 either between a constructor and a conversion op, or between two
5683 if (winner && warn_conversion && cand1->second_conv
5684 && (!DECL_CONSTRUCTOR_P (cand1->fn) || !DECL_CONSTRUCTOR_P (cand2->fn))
5685 && winner != compare_ics (cand1->second_conv, cand2->second_conv))
5687 struct z_candidate *w, *l;
5688 bool give_warning = false;
5691 w = cand1, l = cand2;
5693 w = cand2, l = cand1;
5695 /* We don't want to complain about `X::operator T1 ()'
5696 beating `X::operator T2 () const', when T2 is a no less
5697 cv-qualified version of T1. */
5698 if (DECL_CONTEXT (w->fn) == DECL_CONTEXT (l->fn)
5699 && !DECL_CONSTRUCTOR_P (w->fn) && !DECL_CONSTRUCTOR_P (l->fn))
5701 tree t = TREE_TYPE (TREE_TYPE (l->fn));
5702 tree f = TREE_TYPE (TREE_TYPE (w->fn));
5704 if (TREE_CODE (t) == TREE_CODE (f) && POINTER_TYPE_P (t))
5709 if (!comp_ptr_ttypes (t, f))
5710 give_warning = true;
5713 give_warning = true;
5719 tree source = source_type (TREE_VEC_ELT (w->convs, 0));
5720 if (! DECL_CONSTRUCTOR_P (w->fn))
5721 source = TREE_TYPE (source);
5722 warning ("choosing `%D' over `%D'", w->fn, l->fn);
5723 warning (" for conversion from `%T' to `%T'",
5724 source, TREE_TYPE (w->second_conv));
5725 warning (" because conversion sequence for the argument is better");
5735 F1 is a non-template function and F2 is a template function
5738 if (! cand1->template && cand2->template)
5740 else if (cand1->template && ! cand2->template)
5744 F1 and F2 are template functions and the function template for F1 is
5745 more specialized than the template for F2 according to the partial
5748 if (cand1->template && cand2->template)
5750 winner = more_specialized
5751 (TI_TEMPLATE (cand1->template), TI_TEMPLATE (cand2->template),
5753 /* Tell the deduction code how many real function arguments
5754 we saw, not counting the implicit 'this' argument. But,
5755 add_function_candidate() suppresses the "this" argument
5758 [temp.func.order]: The presence of unused ellipsis and default
5759 arguments has no effect on the partial ordering of function
5761 TREE_VEC_LENGTH (cand1->convs)
5762 - (DECL_NONSTATIC_MEMBER_FUNCTION_P (cand1->fn)
5763 - DECL_CONSTRUCTOR_P (cand1->fn)));
5769 the context is an initialization by user-defined conversion (see
5770 _dcl.init_ and _over.match.user_) and the standard conversion
5771 sequence from the return type of F1 to the destination type (i.e.,
5772 the type of the entity being initialized) is a better conversion
5773 sequence than the standard conversion sequence from the return type
5774 of F2 to the destination type. */
5776 if (cand1->second_conv)
5778 winner = compare_ics (cand1->second_conv, cand2->second_conv);
5783 /* Check whether we can discard a builtin candidate, either because we
5784 have two identical ones or matching builtin and non-builtin candidates.
5786 (Pedantically in the latter case the builtin which matched the user
5787 function should not be added to the overload set, but we spot it here.
5790 ... the builtin candidates include ...
5791 - do not have the same parameter type list as any non-template
5792 non-member candidate. */
5794 if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
5795 || TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
5797 for (i = 0; i < len; ++i)
5798 if (!same_type_p (TREE_TYPE (TREE_VEC_ELT (cand1->convs, i)),
5799 TREE_TYPE (TREE_VEC_ELT (cand2->convs, i))))
5801 if (i == TREE_VEC_LENGTH (cand1->convs))
5803 if (cand1->fn == cand2->fn)
5804 /* Two built-in candidates; arbitrarily pick one. */
5806 else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
5807 /* cand1 is built-in; prefer cand2. */
5810 /* cand2 is built-in; prefer cand1. */
5815 /* If the two functions are the same (this can happen with declarations
5816 in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
5817 if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
5818 && equal_functions (cand1->fn, cand2->fn))
5823 /* Extension: If the worst conversion for one candidate is worse than the
5824 worst conversion for the other, take the first. */
5827 int rank1 = IDENTITY_RANK, rank2 = IDENTITY_RANK;
5828 struct z_candidate *w = 0, *l = 0;
5830 for (i = 0; i < len; ++i)
5832 if (ICS_RANK (TREE_VEC_ELT (cand1->convs, i+off1)) > rank1)
5833 rank1 = ICS_RANK (TREE_VEC_ELT (cand1->convs, i+off1));
5834 if (ICS_RANK (TREE_VEC_ELT (cand2->convs, i+off2)) > rank2)
5835 rank2 = ICS_RANK (TREE_VEC_ELT (cand2->convs, i+off2));
5838 winner = 1, w = cand1, l = cand2;
5840 winner = -1, w = cand2, l = cand1;
5846 ISO C++ says that these are ambiguous, even \
5847 though the worst conversion for the first is better than \
5848 the worst conversion for the second:");
5849 print_z_candidate (_("candidate 1:"), w);
5850 print_z_candidate (_("candidate 2:"), l);
5858 my_friendly_assert (!winner, 20010121);
5862 /* Given a list of candidates for overloading, find the best one, if any.
5863 This algorithm has a worst case of O(2n) (winner is last), and a best
5864 case of O(n/2) (totally ambiguous); much better than a sorting
5867 static struct z_candidate *
5868 tourney (struct z_candidate *candidates)
5870 struct z_candidate *champ = candidates, *challenger;
5872 int champ_compared_to_predecessor = 0;
5874 /* Walk through the list once, comparing each current champ to the next
5875 candidate, knocking out a candidate or two with each comparison. */
5877 for (challenger = champ->next; challenger; )
5879 fate = joust (champ, challenger, 0);
5881 challenger = challenger->next;
5886 champ = challenger->next;
5889 champ_compared_to_predecessor = 0;
5894 champ_compared_to_predecessor = 1;
5897 challenger = champ->next;
5901 /* Make sure the champ is better than all the candidates it hasn't yet
5902 been compared to. */
5904 for (challenger = candidates;
5906 && !(champ_compared_to_predecessor && challenger->next == champ);
5907 challenger = challenger->next)
5909 fate = joust (champ, challenger, 0);
5917 /* Returns nonzero if things of type FROM can be converted to TO. */
5920 can_convert (tree to, tree from)
5922 return can_convert_arg (to, from, NULL_TREE);
5925 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
5928 can_convert_arg (tree to, tree from, tree arg)
5930 tree t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
5931 return (t && ! ICS_BAD_FLAG (t));
5934 /* Like can_convert_arg, but allows dubious conversions as well. */
5937 can_convert_arg_bad (tree to, tree from, tree arg)
5939 return implicit_conversion (to, from, arg, LOOKUP_NORMAL) != 0;
5942 /* Convert EXPR to TYPE. Return the converted expression.
5944 Note that we allow bad conversions here because by the time we get to
5945 this point we are committed to doing the conversion. If we end up
5946 doing a bad conversion, convert_like will complain. */
5949 perform_implicit_conversion (tree type, tree expr)
5953 if (error_operand_p (expr))
5954 return error_mark_node;
5955 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
5959 error ("could not convert `%E' to `%T'", expr, type);
5960 return error_mark_node;
5963 return convert_like (conv, expr);
5966 /* Convert EXPR to TYPE (as a direct-initialization) if that is
5967 permitted. If the conversion is valid, the converted expression is
5968 returned. Otherwise, NULL_TREE is returned. */
5971 perform_direct_initialization_if_possible (tree type, tree expr)
5975 if (type == error_mark_node || error_operand_p (expr))
5976 return error_mark_node;
5977 conv = implicit_conversion (type, TREE_TYPE (expr), expr,
5979 if (!conv || ICS_BAD_FLAG (conv))
5981 return convert_like_real (conv, expr, NULL_TREE, 0, 0,
5982 /*issue_conversion_warnings=*/false);
5985 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
5986 is being bound to a temporary. Create and return a new VAR_DECL
5987 with the indicated TYPE; this variable will store the value to
5988 which the reference is bound. */
5991 make_temporary_var_for_ref_to_temp (tree decl, tree type)
5995 /* Create the variable. */
5996 var = build_decl (VAR_DECL, NULL_TREE, type);
5997 DECL_ARTIFICIAL (var) = 1;
5998 TREE_USED (var) = 1;
6000 /* Register the variable. */
6001 if (TREE_STATIC (decl))
6003 /* Namespace-scope or local static; give it a mangled name. */
6006 TREE_STATIC (var) = 1;
6007 name = mangle_ref_init_variable (decl);
6008 DECL_NAME (var) = name;
6009 SET_DECL_ASSEMBLER_NAME (var, name);
6010 var = pushdecl_top_level (var);
6014 /* Create a new cleanup level if necessary. */
6015 maybe_push_cleanup_level (type);
6016 /* Don't push unnamed temps. Do set DECL_CONTEXT, though. */
6017 DECL_CONTEXT (var) = current_function_decl;
6023 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
6024 initializing a variable of that TYPE. If DECL is non-NULL, it is
6025 the VAR_DECL being initialized with the EXPR. (In that case, the
6026 type of DECL will be TYPE.)
6028 Return the converted expression. */
6031 initialize_reference (tree type, tree expr, tree decl)
6035 if (type == error_mark_node || error_operand_p (expr))
6036 return error_mark_node;
6038 conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
6039 if (!conv || ICS_BAD_FLAG (conv))
6041 if (!(TYPE_QUALS (TREE_TYPE (type)) & TYPE_QUAL_CONST)
6042 && !real_lvalue_p (expr))
6043 error ("invalid initialization of non-const reference of "
6044 "type '%T' from a temporary of type '%T'",
6045 type, TREE_TYPE (expr));
6047 error ("could not convert `%E' to `%T'", expr, type);
6048 return error_mark_node;
6051 /* If DECL is non-NULL, then this special rule applies:
6055 The temporary to which the reference is bound or the temporary
6056 that is the complete object to which the reference is bound
6057 persists for the lifetime of the reference.
6059 The temporaries created during the evaluation of the expression
6060 initializing the reference, except the temporary to which the
6061 reference is bound, are destroyed at the end of the
6062 full-expression in which they are created.
6064 In that case, we store the converted expression into a new
6065 VAR_DECL in a new scope.
6067 However, we want to be careful not to create temporaries when
6068 they are not required. For example, given:
6071 struct D : public B {};
6075 there is no need to copy the return value from "f"; we can just
6076 extend its lifetime. Similarly, given:
6079 struct T { operator S(); };
6083 we can extend the lifetime of the return value of the conversion
6085 my_friendly_assert (TREE_CODE (conv) == REF_BIND, 20030302);
6089 tree base_conv_type;
6091 /* Skip over the REF_BIND. */
6092 conv = TREE_OPERAND (conv, 0);
6093 /* If the next conversion is a BASE_CONV, skip that too -- but
6094 remember that the conversion was required. */
6095 if (TREE_CODE (conv) == BASE_CONV && !NEED_TEMPORARY_P (conv))
6097 base_conv_type = TREE_TYPE (conv);
6098 conv = TREE_OPERAND (conv, 0);
6101 base_conv_type = NULL_TREE;
6102 /* Perform the remainder of the conversion. */
6103 expr = convert_like (conv, expr);
6104 if (!real_non_cast_lvalue_p (expr))
6109 /* Create the temporary variable. */
6110 type = TREE_TYPE (expr);
6111 var = make_temporary_var_for_ref_to_temp (decl, type);
6112 layout_decl (var, 0);
6113 if (at_function_scope_p ())
6117 add_decl_stmt (var);
6118 cleanup = cxx_maybe_build_cleanup (var);
6120 finish_decl_cleanup (var, cleanup);
6124 rest_of_decl_compilation (var, NULL, /*toplev=*/1, at_eof);
6125 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
6126 static_aggregates = tree_cons (NULL_TREE, var,
6129 init = build (INIT_EXPR, type, var, expr);
6130 /* Use its address to initialize the reference variable. */
6131 expr = build_address (var);
6132 expr = build (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
6135 /* Take the address of EXPR. */
6136 expr = build_unary_op (ADDR_EXPR, expr, 0);
6137 /* If a BASE_CONV was required, perform it now. */
6139 expr = (perform_implicit_conversion
6140 (build_pointer_type (base_conv_type), expr));
6141 return build_nop (type, expr);
6144 /* Perform the conversion. */
6145 return convert_like (conv, expr);
6148 #include "gt-cp-call.h"