| blob | 0ba0994d1a6d9fafa2f11104f828425ca70c0cb8 |
1 /* Functions related to invoking methods and overloaded functions.
2 Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com) and
6 modified by Brendan Kehoe (brendan@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
13 any later version.
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
25 /* High-level class interface. */
44 /* The various kinds of conversion. */
47 ck_identity,
48 ck_lvalue,
49 ck_qual,
50 ck_std,
51 ck_ptr,
52 ck_pmem,
53 ck_base,
54 ck_ref_bind,
55 ck_user,
56 ck_ambig,
57 ck_list,
58 ck_aggr,
59 ck_rvalue
62 /* The rank of the conversion. Order of the enumerals matters; better
63 conversions should come earlier in the list. */
66 cr_identity,
67 cr_exact,
68 cr_promotion,
69 cr_std,
70 cr_pbool,
71 cr_user,
72 cr_ellipsis,
73 cr_bad
76 /* An implicit conversion sequence, in the sense of [over.best.ics].
77 The first conversion to be performed is at the end of the chain.
78 That conversion is always a cr_identity conversion. */
82 /* The kind of conversion represented by this step. */
83 conversion_kind kind;
84 /* The rank of this conversion. */
85 conversion_rank rank;
90 /* If KIND is ck_ref_bind ck_base_conv, true to indicate that a
91 temporary should be created to hold the result of the
92 conversion. */
94 /* If KIND is ck_ptr or ck_pmem, true to indicate that a conversion
95 from a pointer-to-derived to pointer-to-base is being performed. */
97 /* If KIND is ck_ref_bind, true when either an lvalue reference is
98 being bound to an lvalue expression or an rvalue reference is
99 being bound to an rvalue expression. */
102 /* The type of the expression resulting from the conversion. */
103 tree type;
105 /* The next conversion in the chain. Since the conversions are
106 arranged from outermost to innermost, the NEXT conversion will
107 actually be performed before this conversion. This variant is
108 used only when KIND is neither ck_identity nor ck_ambig. */
110 /* The expression at the beginning of the conversion chain. This
111 variant is used only if KIND is ck_identity or ck_ambig. */
112 tree expr;
113 /* The array of conversions for an initializer_list. */
116 /* The function candidate corresponding to this conversion
117 sequence. This field is only used if KIND is ck_user. */
119 };
121 #define CONVERSION_RANK(NODE) \
122 ((NODE)->bad_p ? cr_bad \
123 : (NODE)->ellipsis_p ? cr_ellipsis \
124 : (NODE)->user_conv_p ? cr_user \
125 : (NODE)->rank)
136 #define convert_like(CONV, EXPR, COMPLAIN) \
137 convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
140 #define convert_like_with_context(CONV, EXPR, FN, ARGNO, COMPLAIN ) \
141 convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
164 static void add_builtin_candidates
167 static void add_builtin_candidate
171 static void build_builtin_candidate
176 tree);
206 /* Returns nonzero iff the destructor name specified in NAME matches BASETYPE.
207 NAME can take many forms... */
209 bool
211 {
212 /* Just accept something we've already complained about. */
221 {
227 else
229 }
230 else
231 {
232 /* In the case of:
234 template <class T> struct S { ~S(); };
235 int i;
236 i.~S();
238 NAME will be a class template. */
241 }
246 }
248 /* We want the address of a function or method. We avoid creating a
249 pointer-to-member function. */
251 tree
253 {
256 /* We have to do these by hand to avoid real pointer to member
257 functions. */
259 {
261 {
265 }
267 }
268 else
272 }
274 /* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
275 POINTER_TYPE to those. Note, pointer to member function types
276 (TYPE_PTRMEMFUNC_P) must be handled by our callers. There are
277 two variants. build_call_a is the primitive taking an array of
278 arguments, while build_call_n is a wrapper that handles varargs. */
280 tree
282 {
285 else
286 {
296 }
297 }
299 tree
301 {
304 tree decl;
305 tree result_type;
306 tree fntype;
316 /* An rvalue has no cv-qualifiers. */
322 {
325 {
326 /* We invoke build_call directly for several library
327 functions. These may have been declared normally if
328 we're building libgcc, so we can't just check
329 DECL_ARTIFICIAL. */
334 }
335 }
336 else
339 /* We check both the decl and the type; a function may be known not to
340 throw without being declared throw(). */
354 /* Don't pass empty class objects by value. This is useful
355 for tags in STL, which are used to control overload resolution.
356 We don't need to handle other cases of copying empty classes. */
361 {
365 }
373 }
375 /* Build something of the form ptr->method (args)
376 or object.method (args). This can also build
377 calls to constructors, and find friends.
379 Member functions always take their class variable
380 as a pointer.
382 INSTANCE is a class instance.
384 NAME is the name of the method desired, usually an IDENTIFIER_NODE.
386 PARMS help to figure out what that NAME really refers to.
388 BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
389 down to the real instance type to use for access checking. We need this
390 information to get protected accesses correct.
392 FLAGS is the logical disjunction of zero or more LOOKUP_
393 flags. See cp-tree.h for more info.
395 If this is all OK, calls build_function_call with the resolved
396 member function.
398 This function must also handle being called to perform
399 initialization, promotion/coercion of arguments, and
400 instantiation of default parameters.
402 Note that NAME may refer to an instance variable name. If
403 `operator()()' is defined for the type of that field, then we return
404 that result. */
406 /* New overloading code. */
414 };
417 /* The FUNCTION_DECL that will be called if this candidate is
418 selected by overload resolution. */
419 tree fn;
420 /* If not NULL_TREE, the first argument to use when calling this
421 function. */
422 tree first_arg;
423 /* The rest of the arguments to use when calling this function. If
424 there are no further arguments this may be NULL or it may be an
425 empty vector. */
427 /* The implicit conversion sequences for each of the arguments to
428 FN. */
430 /* The number of implicit conversion sequences. */
432 /* If FN is a user-defined conversion, the standard conversion
433 sequence from the type returned by FN to the desired destination
434 type. */
437 /* If FN is a member function, the binfo indicating the path used to
438 qualify the name of FN at the call site. This path is used to
439 determine whether or not FN is accessible if it is selected by
440 overload resolution. The DECL_CONTEXT of FN will always be a
441 (possibly improper) base of this binfo. */
442 tree access_path;
443 /* If FN is a non-static member function, the binfo indicating the
444 subobject to which the `this' pointer should be converted if FN
445 is selected by overload resolution. The type pointed to the by
446 the `this' pointer must correspond to the most derived class
447 indicated by the CONVERSION_PATH. */
448 tree conversion_path;
449 tree template_decl;
452 };
454 /* Returns true iff T is a null pointer constant in the sense of
455 [conv.ptr]. */
457 bool
459 {
460 /* [conv.ptr]
462 A null pointer constant is an integral constant expression
463 (_expr.const_) rvalue of integer type that evaluates to zero. */
468 {
472 }
474 }
476 /* Returns nonzero if PARMLIST consists of only default parms and/or
477 ellipsis. */
479 bool
481 {
487 }
489 /* Allocate N bytes of memory from the conversion obstack. The memory
490 is zeroed before being returned. */
494 {
497 {
500 }
504 }
506 /* Dynamically allocate a conversion. */
510 {
515 }
517 #ifdef ENABLE_CHECKING
519 /* Make sure that all memory on the conversion obstack has been
520 freed. */
522 void
524 {
528 }
532 /* Dynamically allocate an array of N conversions. */
536 {
538 }
542 {
546 /* Note that the caller is responsible for filling in t->cand for
547 user-defined conversions. */
553 {
569 }
575 }
577 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, a
578 specialization of std::initializer_list<T>, if such a conversion is
579 possible. */
583 {
589 tree val;
592 {
593 conversion *sub
600 }
608 {
616 }
619 }
621 /* Represent a conversion from CTOR, a braced-init-list, to TYPE, an
622 aggregate class, if such a conversion is possible. */
626 {
632 {
634 {
642 }
645 }
656 }
658 /* Build a representation of the identity conversion from EXPR to
659 itself. The TYPE should match the type of EXPR, if EXPR is non-NULL. */
663 {
671 }
673 /* Converting from EXPR to TYPE was ambiguous in the sense that there
674 were multiple user-defined conversions to accomplish the job.
675 Build a conversion that indicates that ambiguity. */
679 {
687 }
689 tree
691 {
695 }
697 /* Returns the standard conversion path (see [conv]) from type FROM to type
698 TO, if any. For proper handling of null pointer constants, you must
699 also pass the expression EXPR to convert from. If C_CAST_P is true,
700 this conversion is coming from a C-style cast. */
705 {
712 {
715 }
721 {
729 }
736 {
740 }
742 {
744 {
745 tree bitfield_type;
748 {
751 }
752 }
754 }
756 /* Allow conversion between `__complex__' data types. */
758 {
759 /* The standard conversion sequence to convert FROM to TO is
760 the standard conversion sequence to perform componentwise
761 conversion. */
766 {
769 }
770 else
774 }
784 {
785 /* For backwards brain damage compatibility, allow interconversion of
786 pointers and integers with a pedwarn. */
789 }
791 {
792 /* For backwards brain damage compatibility, allow interconversion of
793 enums and integers with a pedwarn. */
796 }
799 {
800 tree to_pointee;
801 tree from_pointee;
806 ;
810 {
811 from = build_pointer_type
815 }
817 {
822 && (same_type_ignoring_top_level_qualifiers_p
825 {
829 }
832 }
835 /* [conv.ptr]
837 An rvalue of type "pointer to cv D," where D is a
838 class type, can be converted to an rvalue of type
839 "pointer to cv B," where B is a base class (clause
840 _class.derived_) of D. If B is an inaccessible
841 (clause _class.access_) or ambiguous
842 (_class.member.lookup_) base class of D, a program
843 that necessitates this conversion is ill-formed.
844 Therefore, we use DERIVED_FROM_P, and do not check
845 access or uniqueness. */
847 {
848 from =
854 }
857 {
860 }
861 else
862 {
865 }
870 /* In a C-style cast, we ignore CV-qualification because we
871 are allowed to perform a static_cast followed by a
872 const_cast. */
877 /* converting from string constant to char *. */
880 {
883 }
884 else
888 }
890 {
907 }
909 {
910 /* [conv.bool]
912 An rvalue of arithmetic, unscoped enumeration, pointer, or
913 pointer to member type can be converted to an rvalue of type
914 bool. */
919 {
927 }
930 }
931 /* We don't check for ENUMERAL_TYPE here because there are no standard
932 conversions to enum type. */
933 /* As an extension, allow conversion to complex type. */
935 {
941 /* Give this a better rank if it's a promotion. */
945 }
951 {
955 /* The derived-to-base conversion indicates the initialization
956 of a parameter with base type from an object of a derived
957 type. A temporary object is created to hold the result of
958 the conversion unless we're binding directly to a reference. */
960 }
961 else
968 }
970 /* Returns nonzero if T1 is reference-related to T2. */
972 bool
974 {
978 /* [dcl.init.ref]
980 Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
981 to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
982 of T2. */
986 }
988 /* Returns nonzero if T1 is reference-compatible with T2. */
990 static bool
992 {
993 /* [dcl.init.ref]
995 "cv1 T1" is reference compatible with "cv2 T2" if T1 is
996 reference-related to T2 and cv1 is the same cv-qualification as,
997 or greater cv-qualification than, cv2. */
1000 }
1002 /* Determine whether or not the EXPR (of class type S) can be
1003 converted to T as in [over.match.ref]. */
1007 {
1008 tree conversions;
1009 tree first_arg;
1011 tree t;
1020 /* [over.match.ref]
1022 Assuming that "cv1 T" is the underlying type of the reference
1023 being initialized, and "cv S" is the type of the initializer
1024 expression, with S a class type, the candidate functions are
1025 selected as follows:
1027 --The conversion functions of S and its base classes are
1028 considered. Those that are not hidden within S and yield type
1029 "reference to cv2 T2", where "cv1 T" is reference-compatible
1030 (_dcl.init.ref_) with "cv2 T2", are candidate functions.
1032 The argument list has one argument, which is the initializer
1033 expression. */
1037 /* Conceptually, we should take the address of EXPR and put it in
1038 the argument list. Unfortunately, however, that can result in
1039 error messages, which we should not issue now because we are just
1040 trying to find a conversion operator. Therefore, we use NULL,
1041 cast to the appropriate type. */
1047 {
1051 {
1061 /* If this is a template function, try to get an exact
1062 match. */
1064 {
1067 NULL_TREE,
1068 first_arg,
1069 NULL,
1070 reference_type,
1073 LOOKUP_NORMAL,
1074 DEDUCE_CONV);
1077 {
1078 /* Now, see if the conversion function really returns
1079 an lvalue of the appropriate type. From the
1080 point of view of unification, simply returning an
1081 rvalue of the right type is good enough. */
1086 {
1089 }
1090 }
1091 }
1097 LOOKUP_NORMAL);
1100 {
1102 /* Build a standard conversion sequence indicating the
1103 binding from the reference type returned by the
1104 function to the desired REFERENCE_TYPE. */
1105 identity_conv
1108 NULL_TREE);
1109 cand->second_conv
1110 = (direct_reference_binding
1117 /* Don't allow binding of lvalues to rvalue references. */
1121 }
1122 }
1123 }
1126 /* If none of the conversion functions worked out, let our caller
1127 know. */
1135 /* Now that we know that this is the function we're going to use fix
1136 the dummy first argument. */
1141 /* Build a user-defined conversion sequence representing the
1142 conversion. */
1151 /* Merge it with the standard conversion sequence from the
1152 conversion function's return type to the desired type. */
1156 }
1158 /* A reference of the indicated TYPE is being bound directly to the
1159 expression represented by the implicit conversion sequence CONV.
1160 Return a conversion sequence for this binding. */
1164 {
1165 tree t;
1172 /* [over.ics.rank]
1174 When a parameter of reference type binds directly
1175 (_dcl.init.ref_) to an argument expression, the implicit
1176 conversion sequence is the identity conversion, unless the
1177 argument expression has a type that is a derived class of the
1178 parameter type, in which case the implicit conversion sequence is
1179 a derived-to-base Conversion.
1181 If the parameter binds directly to the result of applying a
1182 conversion function to the argument expression, the implicit
1183 conversion sequence is a user-defined conversion sequence
1184 (_over.ics.user_), with the second standard conversion sequence
1185 either an identity conversion or, if the conversion function
1186 returns an entity of a type that is a derived class of the
1187 parameter type, a derived-to-base conversion. */
1189 {
1190 /* Represent the derived-to-base conversion. */
1192 /* We will actually be binding to the base-class subobject in
1193 the derived class, so we mark this conversion appropriately.
1194 That way, convert_like knows not to generate a temporary. */
1196 }
1198 }
1200 /* Returns the conversion path from type FROM to reference type TO for
1201 purposes of reference binding. For lvalue binding, either pass a
1202 reference type to FROM or an lvalue expression to EXPR. If the
1203 reference will be bound to a temporary, NEED_TEMPORARY_P is set for
1204 the conversion returned. If C_CAST_P is true, this
1205 conversion is coming from a C-style cast. */
1209 {
1213 tree tfrom;
1219 {
1224 }
1227 {
1228 /* Anything with reference type is an lvalue. */
1231 }
1234 {
1237 flags);
1240 {
1245 }
1246 }
1255 /* Figure out whether or not the types are reference-related and
1256 reference compatible. We have do do this after stripping
1257 references from FROM. */
1259 /* If this is a C cast, first convert to an appropriately qualified
1260 type, so that we can later do a const_cast to the desired type. */
1266 /* Directly bind reference when target expression's type is compatible with
1267 the reference and expression is an lvalue. In DR391, the wording in
1268 [8.5.3/5 dcl.init.ref] is changed to also require direct bindings for
1269 const and rvalue references to rvalues of compatible class type.
1270 We should also do direct bindings for non-class "rvalues" derived from
1271 rvalue references. */
1273 && (is_lvalue
1278 {
1279 /* [dcl.init.ref]
1281 If the initializer expression
1283 -- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
1284 is reference-compatible with "cv2 T2,"
1286 the reference is bound directly to the initializer expression
1287 lvalue.
1289 [...]
1290 If the initializer expression is an rvalue, with T2 a class type,
1291 and "cv1 T1" is reference-compatible with "cv2 T2", the reference
1292 is bound to the object represented by the rvalue or to a sub-object
1293 within that object. */
1299 /* The top-level caller requested that we pretend that the lvalue
1300 be treated as an rvalue. */
1302 else
1303 conv->rvaluedness_matches_p
1308 /* For the purposes of overload resolution, we ignore the fact
1309 this expression is a bitfield or packed field. (In particular,
1310 [over.ics.ref] says specifically that a function with a
1311 non-const reference parameter is viable even if the
1312 argument is a bitfield.)
1314 However, when we actually call the function we must create
1315 a temporary to which to bind the reference. If the
1316 reference is volatile, or isn't const, then we cannot make
1317 a temporary, so we just issue an error when the conversion
1318 actually occurs. */
1321 /* Don't allow binding of lvalues to rvalue references. */
1327 }
1328 /* [class.conv.fct] A conversion function is never used to convert a
1329 (possibly cv-qualified) object to the (possibly cv-qualified) same
1330 object type (or a reference to it), to a (possibly cv-qualified) base
1331 class of that type (or a reference to it).... */
1334 {
1335 /* [dcl.init.ref]
1337 If the initializer expression
1339 -- has a class type (i.e., T2 is a class type) can be
1340 implicitly converted to an lvalue of type "cv3 T3," where
1341 "cv1 T1" is reference-compatible with "cv3 T3". (this
1342 conversion is selected by enumerating the applicable
1343 conversion functions (_over.match.ref_) and choosing the
1344 best one through overload resolution. (_over.match_).
1346 the reference is bound to the lvalue result of the conversion
1347 in the second case. */
1351 }
1353 /* From this point on, we conceptually need temporaries, even if we
1354 elide them. Only the cases above are "direct bindings". */
1358 /* [over.ics.rank]
1360 When a parameter of reference type is not bound directly to an
1361 argument expression, the conversion sequence is the one required
1362 to convert the argument expression to the underlying type of the
1363 reference according to _over.best.ics_. Conceptually, this
1364 conversion sequence corresponds to copy-initializing a temporary
1365 of the underlying type with the argument expression. Any
1366 difference in top-level cv-qualification is subsumed by the
1367 initialization itself and does not constitute a conversion. */
1369 /* [dcl.init.ref]
1371 Otherwise, the reference shall be to a non-volatile const type.
1373 Under C++0x, [8.5.3/5 dcl.init.ref] it may also be an rvalue reference */
1377 /* [dcl.init.ref]
1379 Otherwise, a temporary of type "cv1 T1" is created and
1380 initialized from the initializer expression using the rules for a
1381 non-reference copy initialization. If T1 is reference-related to
1382 T2, cv1 must be the same cv-qualification as, or greater
1383 cv-qualification than, cv2; otherwise, the program is ill-formed. */
1387 /* We're generating a temporary now, but don't bind any more in the
1388 conversion (specifically, don't slice the temporary returned by a
1389 conversion operator). */
1392 /* Temporaries are copy-initialized, except for this hack to allow
1393 explicit conversion ops to the copy ctor. See also
1394 add_function_candidate. */
1400 flags);
1405 /* This reference binding, unlike those above, requires the
1406 creation of a temporary. */
1411 }
1413 /* Returns the implicit conversion sequence (see [over.ics]) from type
1414 FROM to type TO. The optional expression EXPR may affect the
1415 conversion. FLAGS are the usual overloading flags. If C_CAST_P is
1416 true, this conversion is coming from a C-style cast. */
1421 {
1430 else
1437 {
1441 /* Allow conversion from an initializer-list with one element to a
1442 scalar type. */
1444 {
1446 tree elt;
1452 else
1458 {
1461 /* Too many levels of braces, i.e. '{{1}}'. */
1464 }
1465 }
1466 }
1472 {
1485 /* We used to try to bind a reference to a temporary here, but that
1486 is now handled after the recursive call to this function at the end
1487 of reference_binding. */
1489 }
1492 }
1494 /* Add a new entry to the list of candidates. Used by the add_*_candidate
1495 functions. ARGS will not be changed until a single candidate is
1496 selected. */
1504 {
1520 }
1522 /* Create an overload candidate for the function or method FN called
1523 with the argument list FIRST_ARG/ARGS and add it to CANDIDATES.
1524 FLAGS is passed on to implicit_conversion.
1526 This does not change ARGS.
1528 CTYPE, if non-NULL, is the type we want to pretend this function
1529 comes from for purposes of overload resolution. */
1536 {
1540 tree parmnode;
1545 /* At this point we should not see any functions which haven't been
1546 explicitly declared, except for friend functions which will have
1547 been found using argument dependent lookup. */
1550 /* The `this', `in_chrg' and VTT arguments to constructors are not
1551 considered in overload resolution. */
1553 {
1557 {
1560 }
1561 }
1562 else
1568 /* 13.3.2 - Viable functions [over.match.viable]
1569 First, to be a viable function, a candidate function shall have enough
1570 parameters to agree in number with the arguments in the list.
1572 We need to check this first; otherwise, checking the ICSes might cause
1573 us to produce an ill-formed template instantiation. */
1577 {
1581 }
1586 /* Make sure there are default args for the rest of the parms. */
1593 /* Second, for F to be a viable function, there shall exist for each
1594 argument an implicit conversion sequence that converts that argument
1595 to the corresponding parameter of F. */
1600 {
1610 else
1619 {
1623 /* The type of the implicit object parameter ('this') for
1624 overload resolution is not always the same as for the
1625 function itself; conversion functions are considered to
1626 be members of the class being converted, and functions
1627 introduced by a using-declaration are considered to be
1628 members of the class that uses them.
1630 Since build_over_call ignores the ICS for the `this'
1631 parameter, we can just change the parm type. */
1633 {
1634 parmtype
1638 }
1642 {
1643 /* Hack: Direct-initialize copy parm (i.e. suppress
1644 LOOKUP_ONLYCONVERTING) to make explicit conversion ops
1645 work. See also reference_binding. */
1649 }
1650 else
1655 }
1656 else
1657 {
1660 }
1667 {
1670 }
1677 }
1679 out:
1682 }
1684 /* Create an overload candidate for the conversion function FN which will
1685 be invoked for expression OBJ, producing a pointer-to-function which
1686 will in turn be called with the argument list FIRST_ARG/ARGLIST,
1687 and add it to CANDIDATES. This does not change ARGLIST. FLAGS is
1688 passed on to implicit_conversion.
1690 Actually, we don't really care about FN; we care about the type it
1691 converts to. There may be multiple conversion functions that will
1692 convert to that type, and we rely on build_user_type_conversion_1 to
1693 choose the best one; so when we create our candidate, we record the type
1694 instead of the function. */
1700 {
1716 /* Don't bother looking up the same type twice. */
1721 {
1729 else
1736 flags);
1742 else
1743 {
1746 }
1760 }
1770 }
1772 static void
1776 {
1789 /* TRUTH_*_EXPR do "contextual conversion to bool", which means explicit
1790 conversion ops are allowed. We handle that here by just checking for
1791 boolean_type_node because other operators don't ask for it. COND_EXPR
1792 also does contextual conversion to bool for the first operand, but we
1793 handle that in build_conditional_expr, and type1 here is operand 2. */
1798 {
1805 {
1807 /* We need something for printing the candidate. */
1809 }
1813 }
1815 /* For COND_EXPR we rearranged the arguments; undo that now. */
1817 {
1824 else
1826 }
1832 viable);
1833 }
1835 static bool
1837 {
1839 }
1841 /* Returns nonzero if TYPE is a promoted arithmetic type. */
1843 static bool
1845 {
1846 /* [over.built]
1848 In this section, the term promoted integral type is used to refer
1849 to those integral types which are preserved by integral promotion
1850 (including e.g. int and long but excluding e.g. char).
1851 Similarly, the term promoted arithmetic type refers to promoted
1852 integral types plus floating types. */
1856 }
1858 /* Create any builtin operator overload candidates for the operator in
1859 question given the converted operand types TYPE1 and TYPE2. The other
1860 args are passed through from add_builtin_candidates to
1861 build_builtin_candidate.
1863 TYPE1 and TYPE2 may not be permissible, and we must filter them.
1864 If CODE is requires candidates operands of the same type of the kind
1865 of which TYPE1 and TYPE2 are, we add both candidates
1866 CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
1868 static void
1872 {
1874 {
1882 }
1885 {
1887 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
1888 and VQ is either volatile or empty, there exist candidate operator
1889 functions of the form
1890 VQ T& operator++(VQ T&);
1891 T operator++(VQ T&, int);
1892 5 For every pair T, VQ), where T is an enumeration type or an arithmetic
1893 type other than bool, and VQ is either volatile or empty, there exist
1894 candidate operator functions of the form
1895 VQ T& operator--(VQ T&);
1896 T operator--(VQ T&, int);
1897 6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
1898 complete object type, and VQ is either volatile or empty, there exist
1899 candidate operator functions of the form
1900 T*VQ& operator++(T*VQ&);
1901 T*VQ& operator--(T*VQ&);
1902 T* operator++(T*VQ&, int);
1903 T* operator--(T*VQ&, int); */
1912 {
1915 }
1918 /* 7 For every cv-qualified or cv-unqualified complete object type T, there
1919 exist candidate operator functions of the form
1921 T& operator*(T*);
1923 8 For every function type T, there exist candidate operator functions of
1924 the form
1925 T& operator*(T*); */
1934 /* 9 For every type T, there exist candidate operator functions of the form
1935 T* operator+(T*);
1937 10For every promoted arithmetic type T, there exist candidate operator
1938 functions of the form
1939 T operator+(T);
1940 T operator-(T); */
1950 /* 11For every promoted integral type T, there exist candidate operator
1951 functions of the form
1952 T operator~(T); */
1959 /* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
1960 is the same type as C2 or is a derived class of C2, T is a complete
1961 object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
1962 there exist candidate operator functions of the form
1963 CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
1964 where CV12 is the union of CV1 and CV2. */
1969 {
1977 }
1980 /* 13For every pair of promoted arithmetic types L and R, there exist can-
1981 didate operator functions of the form
1982 LR operator*(L, R);
1983 LR operator/(L, R);
1984 LR operator+(L, R);
1985 LR operator-(L, R);
1986 bool operator<(L, R);
1987 bool operator>(L, R);
1988 bool operator<=(L, R);
1989 bool operator>=(L, R);
1990 bool operator==(L, R);
1991 bool operator!=(L, R);
1992 where LR is the result of the usual arithmetic conversions between
1993 types L and R.
1995 14For every pair of types T and I, where T is a cv-qualified or cv-
1996 unqualified complete object type and I is a promoted integral type,
1997 there exist candidate operator functions of the form
1998 T* operator+(T*, I);
1999 T& operator[](T*, I);
2000 T* operator-(T*, I);
2001 T* operator+(I, T*);
2002 T& operator[](I, T*);
2004 15For every T, where T is a pointer to complete object type, there exist
2005 candidate operator functions of the form112)
2006 ptrdiff_t operator-(T, T);
2008 16For every pointer or enumeration type T, there exist candidate operator
2009 functions of the form
2010 bool operator<(T, T);
2011 bool operator>(T, T);
2012 bool operator<=(T, T);
2013 bool operator>=(T, T);
2014 bool operator==(T, T);
2015 bool operator!=(T, T);
2017 17For every pointer to member type T, there exist candidate operator
2018 functions of the form
2019 bool operator==(T, T);
2020 bool operator!=(T, T); */
2027 {
2030 }
2043 {
2046 }
2048 {
2051 }
2052 /* Fall through. */
2069 {
2072 }
2076 {
2079 }
2087 {
2090 }
2092 {
2095 }
2098 /* 18For every pair of promoted integral types L and R, there exist candi-
2099 date operator functions of the form
2100 LR operator%(L, R);
2101 LR operator&(L, R);
2102 LR operator^(L, R);
2103 LR operator|(L, R);
2104 L operator<<(L, R);
2105 L operator>>(L, R);
2106 where LR is the result of the usual arithmetic conversions between
2107 types L and R. */
2115 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2119 /* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
2120 type, VQ is either volatile or empty, and R is a promoted arithmetic
2121 type, there exist candidate operator functions of the form
2122 VQ L& operator=(VQ L&, R);
2123 VQ L& operator*=(VQ L&, R);
2124 VQ L& operator/=(VQ L&, R);
2125 VQ L& operator+=(VQ L&, R);
2126 VQ L& operator-=(VQ L&, R);
2128 20For every pair T, VQ), where T is any type and VQ is either volatile
2129 or empty, there exist candidate operator functions of the form
2130 T*VQ& operator=(T*VQ&, T*);
2132 21For every pair T, VQ), where T is a pointer to member type and VQ is
2133 either volatile or empty, there exist candidate operator functions of
2134 the form
2135 VQ T& operator=(VQ T&, T);
2137 22For every triple T, VQ, I), where T is a cv-qualified or cv-
2138 unqualified complete object type, VQ is either volatile or empty, and
2139 I is a promoted integral type, there exist candidate operator func-
2140 tions of the form
2141 T*VQ& operator+=(T*VQ&, I);
2142 T*VQ& operator-=(T*VQ&, I);
2144 23For every triple L, VQ, R), where L is an integral or enumeration
2145 type, VQ is either volatile or empty, and R is a promoted integral
2146 type, there exist candidate operator functions of the form
2148 VQ L& operator%=(VQ L&, R);
2149 VQ L& operator<<=(VQ L&, R);
2150 VQ L& operator>>=(VQ L&, R);
2151 VQ L& operator&=(VQ L&, R);
2152 VQ L& operator^=(VQ L&, R);
2153 VQ L& operator|=(VQ L&, R); */
2157 {
2161 {
2164 }
2177 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type1) && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type2))
2190 {
2193 }
2198 }
2203 /* [over.built]
2205 For every pair of promoted arithmetic types L and R, there
2206 exist candidate operator functions of the form
2208 LR operator?(bool, L, R);
2210 where LR is the result of the usual arithmetic conversions
2211 between types L and R.
2213 For every type T, where T is a pointer or pointer-to-member
2214 type, there exist candidate operator functions of the form T
2215 operator?(bool, T, T); */
2219 /* That's OK. */
2222 /* Otherwise, the types should be pointers. */
2227 /* We don't check that the two types are the same; the logic
2228 below will actually create two candidates; one in which both
2229 parameter types are TYPE1, and one in which both parameter
2230 types are TYPE2. */
2235 }
2237 /* If we're dealing with two pointer types or two enumeral types,
2238 we need candidates for both of them. */
2247 {
2248 build_builtin_candidate
2250 build_builtin_candidate
2253 }
2255 build_builtin_candidate
2257 }
2259 tree
2261 {
2269 }
2271 /* There are three conditions of builtin candidates:
2273 1) bool-taking candidates. These are the same regardless of the input.
2274 2) pointer-pair taking candidates. These are generated for each type
2275 one of the input types converts to.
2276 3) arithmetic candidates. According to the standard, we should generate
2277 all of these, but I'm trying not to...
2279 Here we generate a superset of the possible candidates for this particular
2280 case. That is a subset of the full set the standard defines, plus some
2281 other cases which the standard disallows. add_builtin_candidate will
2282 filter out the invalid set. */
2284 static void
2288 {
2292 /* TYPES[i] is the set of possible builtin-operator parameter types
2293 we will consider for the Ith argument. These are represented as
2294 a TREE_LIST; the TREE_VALUE of each node is the potential
2295 parameter type. */
2299 {
2302 else
2304 }
2307 {
2308 /* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
2309 and VQ is either volatile or empty, there exist candidate operator
2310 functions of the form
2311 VQ T& operator++(VQ T&); */
2321 /* 24There also exist candidate operator functions of the form
2322 bool operator!(bool);
2323 bool operator&&(bool, bool);
2324 bool operator||(bool, bool); */
2327 build_builtin_candidate
2334 build_builtin_candidate
2352 /* Fall through. */
2356 }
2361 {
2363 ;
2365 {
2366 tree convs;
2375 {
2382 }
2388 {
2401 {
2407 }
2411 }
2412 }
2413 else
2414 {
2420 {
2426 }
2428 }
2429 }
2431 /* Run through the possible parameter types of both arguments,
2432 creating candidates with those parameter types. */
2434 {
2437 add_builtin_candidate
2440 else
2441 add_builtin_candidate
2444 }
2445 }
2448 /* If TMPL can be successfully instantiated as indicated by
2449 EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
2451 TMPL is the template. EXPLICIT_TARGS are any explicit template
2452 arguments. ARGLIST is the arguments provided at the call-site.
2453 This does not change ARGLIST. The RETURN_TYPE is the desired type
2454 for conversion operators. If OBJ is NULL_TREE, FLAGS and CTYPE are
2455 as for add_function_candidate. If an OBJ is supplied, FLAGS and
2456 CTYPE are ignored, and OBJ is as for add_conv_candidate. */
2464 {
2474 tree arg;
2477 tree fn;
2479 /* We don't do deduction on the in-charge parameter, the VTT
2480 parameter or 'this'. */
2482 {
2485 else
2487 }
2492 {
2495 else
2497 }
2507 {
2510 }
2514 {
2517 }
2521 args_without_in_chrg,
2522 nargs_without_in_chrg,
2532 /* In [class.copy]:
2534 A member function template is never instantiated to perform the
2535 copy of a class object to an object of its class type.
2537 It's a little unclear what this means; the standard explicitly
2538 does allow a template to be used to copy a class. For example,
2539 in:
2541 struct A {
2542 A(A&);
2543 template <class T> A(const T&);
2544 };
2545 const A f ();
2546 void g () { A a (f ()); }
2548 the member template will be used to make the copy. The section
2549 quoted above appears in the paragraph that forbids constructors
2550 whose only parameter is (a possibly cv-qualified variant of) the
2551 class type, and a logical interpretation is that the intent was
2552 to forbid the instantiation of member templates which would then
2553 have that form. */
2555 {
2558 ctype))
2560 }
2563 /* Aha, this is a conversion function. */
2566 else
2571 /* This situation can occur if a member template of a template
2572 class is specialized. Then, instantiate_template might return
2573 an instantiation of the specialization, in which case the
2574 DECL_TI_TEMPLATE field will point at the original
2575 specialization. For example:
2577 template <class T> struct S { template <class U> void f(U);
2578 template <> void f(int) {}; };
2579 S<double> sd;
2580 sd.f(3);
2582 Here, TMPL will be template <class U> S<double>::f(U).
2583 And, instantiate template will give us the specialization
2584 template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
2585 for this will point at template <class T> template <> S<T>::f(int),
2586 so that we can find the definition. For the purposes of
2587 overload resolution, however, we want the original TMPL. */
2589 else
2593 }
2601 unification_kind_t strict)
2602 {
2603 return
2608 }
2616 tree conversion_path)
2617 {
2618 return
2622 }
2624 /* The CANDS are the set of candidates that were considered for
2625 overload resolution. Return the set of viable candidates. If none
2626 of the candidates were viable, set *ANY_VIABLE_P to true. STRICT_P
2627 is true if a candidate should be considered viable only if it is
2628 strictly viable. */
2634 {
2645 {
2648 {
2654 }
2655 else
2657 }
2660 }
2662 static bool
2664 {
2669 }
2671 /* OBJ is being used in an expression like "OBJ.f (...)". In other
2672 words, it is about to become the "this" pointer for a member
2673 function call. Take the address of the object. */
2675 static tree
2677 {
2678 /* In a template, we are only concerned about the type of the
2679 expression, so we can take a shortcut. */
2684 }
2686 /* Returns true iff functions are equivalent. Equivalent functions are
2687 not '==' only if one is a function-local extern function or if
2688 both are extern "C". */
2692 {
2697 }
2699 /* Print information about one overload candidate CANDIDATE. MSGSTR
2700 is the text to print before the candidate itself.
2702 NOTE: Unlike most diagnostic functions in GCC, MSGSTR is expected
2703 to have been run through gettext by the caller. This wart makes
2704 life simpler in print_z_candidates and for the translators. */
2706 static void
2708 {
2710 {
2720 else
2723 }
2730 else
2732 }
2734 static void
2736 {
2745 /* Remove deleted candidates. */
2748 {
2752 else
2754 }
2755 /* ...if there are any non-deleted ones. */
2759 /* There may be duplicates in the set of candidates. We put off
2760 checking this condition as long as possible, since we have no way
2761 to eliminate duplicates from a set of functions in less than n^2
2762 time. Now we are about to emit an error message, so it is more
2763 permissible to go slowly. */
2765 {
2767 /* Skip builtin candidates and conversion functions. */
2772 {
2776 else
2778 }
2779 }
2784 {
2787 }
2789 }
2791 /* USER_SEQ is a user-defined conversion sequence, beginning with a
2792 USER_CONV. STD_SEQ is the standard conversion sequence applied to
2793 the result of the conversion function to convert it to the final
2794 desired type. Merge the two sequences into a single sequence,
2795 and return the merged sequence. */
2799 {
2804 /* Find the end of the second conversion sequence. */
2809 /* Replace the identity conversion with the user conversion
2810 sequence. */
2813 /* The entire sequence is a user-conversion sequence. */
2817 }
2819 /* Returns the best overload candidate to perform the requested
2820 conversion. This function is used for three the overloading situations
2821 described in [over.match.copy], [over.match.conv], and [over.match.ref].
2822 If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
2823 per [dcl.init.ref], so we ignore temporary bindings. */
2827 {
2838 /* We represent conversion within a hierarchy using RVALUE_CONV and
2839 BASE_CONV, as specified by [over.best.ics]; these become plain
2840 constructor calls, as specified in [dcl.init]. */
2848 {
2853 {
2854 /* [class.conv.fct] A conversion function is never used to
2855 convert a (possibly cv-qualified) object to the (possibly
2856 cv-qualified) same object type (or a reference to it), to a
2857 (possibly cv-qualified) base class of that type (or a
2858 reference to it)... */
2859 }
2860 else
2863 }
2868 /* It's OK to bind a temporary for converting constructor arguments, but
2869 not in converting the return value of a conversion operator. */
2874 {
2880 {
2882 /* We still allow more conversions within an init-list. */
2884 /* But not for the copy ctor. */
2885 |LOOKUP_NO_COPY_CTOR_CONVERSION
2887 }
2888 else
2891 /* We should never try to call the abstract or base constructor
2892 from here. */
2895 }
2897 {
2908 flags,
2909 DEDUCE_CALL);
2910 else
2914 flags);
2917 {
2920 /* If totype isn't a reference, and LOOKUP_NO_TEMP_BIND isn't
2921 set, then this is copy-initialization. In that case, "The
2922 result of the call is then used to direct-initialize the
2923 object that is the destination of the copy-initialization."
2924 [dcl.init]
2926 We represent this in the conversion sequence with an
2927 rvalue conversion, which means a constructor call. */
2930 cand->second_conv
2932 }
2933 }
2939 {
2940 tree fns;
2943 /* If we are called to convert to a reference type, we are trying to
2944 find an lvalue binding, so don't even consider temporaries. If
2945 we don't find an lvalue binding, the caller will try again to
2946 look for a temporary binding. */
2951 {
2958 /* [over.match.funcs] For conversion functions, the function
2959 is considered to be a member of the class of the implicit
2960 object argument for the purpose of defining the type of
2961 the implicit object parameter.
2963 So we pass fromtype as CTYPE to add_*_candidate. */
2967 NULL_TREE,
2970 conversion_path,
2971 flags,
2972 DEDUCE_CONV);
2973 else
2977 conversion_path,
2978 flags);
2981 {
2982 conversion *ics
2988 /* If LOOKUP_NO_TEMP_BIND isn't set, then this is
2989 copy-initialization. In that case, "The result of the
2990 call is then used to direct-initialize the object that is
2991 the destination of the copy-initialization." [dcl.init]
2993 We represent this in the conversion sequence with an
2994 rvalue conversion, which means a constructor call. But
2995 don't add a second rvalue conversion if there's already
2996 one there. Which there really shouldn't be, but it's
2997 harmless since we'd add it here anyway. */
3008 }
3009 }
3010 }
3018 {
3020 {
3024 }
3031 /* If there are viable candidates, don't set ICS_BAD_FLAG; an
3032 ambiguous conversion is no worse than another user-defined
3033 conversion. */
3036 }
3038 /* Build the user conversion sequence. */
3039 conv = build_conv
3046 /* Remember that this was a list-initialization. */
3050 /* Combine it with the second conversion sequence. */
3058 }
3060 tree
3062 {
3067 {
3072 }
3074 }
3076 /* Do any initial processing on the arguments to a function call. */
3080 {
3082 tree arg;
3085 {
3089 {
3092 }
3095 }
3097 }
3099 /* Perform overload resolution on FN, which is called with the ARGS.
3101 Return the candidate function selected by overload resolution, or
3102 NULL if the event that overload resolution failed. In the case
3103 that overload resolution fails, *CANDIDATES will be the set of
3104 candidates considered, and ANY_VIABLE_P will be set to true or
3105 false to indicate whether or not any of the candidates were
3106 viable.
3108 The ARGS should already have gone through RESOLVE_ARGS before this
3109 function is called. */
3116 {
3124 /* Check FN. */
3131 {
3135 }
3137 /* Add the various candidate functions. */
3141 LOOKUP_NORMAL,
3142 candidates);
3150 }
3152 /* Return an expression for a call to FN (a namespace-scope function,
3153 or a static member function) with the ARGS. This may change
3154 ARGS. */
3156 tree
3158 tsubst_flags_t complain)
3159 {
3163 tree result;
3166 {
3170 }
3172 /* If this function was found without using argument dependent
3173 lookup, then we want to ignore any undeclared friend
3174 functions. */
3176 {
3181 {
3187 }
3188 }
3190 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3196 {
3198 {
3206 else
3211 }
3213 }
3214 else
3217 /* Free all the conversions we allocated. */
3221 }
3223 /* Build a call to a global operator new. FNNAME is the name of the
3224 operator (either "operator new" or "operator new[]") and ARGS are
3225 the arguments provided. This may change ARGS. *SIZE points to the
3226 total number of bytes required by the allocation, and is updated if
3227 that is changed here. *COOKIE_SIZE is non-NULL if a cookie should
3228 be used. If this function determines that no cookie should be
3229 used, after all, *COOKIE_SIZE is set to NULL_TREE. If FN is
3230 non-NULL, it will be set, upon return, to the allocation function
3231 called. */
3233 tree
3237 {
3238 tree fns;
3250 /* Based on:
3252 [expr.new]
3254 If this lookup fails to find the name, or if the allocated type
3255 is not a class type, the allocation function's name is looked
3256 up in the global scope.
3258 we disregard block-scope declarations of "operator new". */
3261 /* Figure out what function is being called. */
3264 /* If no suitable function could be found, issue an error message
3265 and give up. */
3267 {
3271 else
3277 }
3279 /* If a cookie is required, add some extra space. Whether
3280 or not a cookie is required cannot be determined until
3281 after we know which function was called. */
3283 {
3286 {
3287 /* In G++ 3.2, the check was implemented incorrectly; it
3288 looked at the placement expression, rather than the
3289 type of the function. */
3292 ptr_type_node))
3294 }
3295 else
3296 {
3297 tree arg_types;
3300 /* Skip the size_t parameter. */
3302 /* Check the remaining parameters (if any). */
3306 ptr_type_node))
3308 }
3309 /* If we need a cookie, adjust the number of bytes allocated. */
3311 {
3312 /* Update the total size. */
3314 /* Update the argument list to reflect the adjusted size. */
3316 }
3317 else
3319 }
3321 /* Tell our caller which function we decided to call. */
3325 /* Build the CALL_EXPR. */
3327 }
3329 /* Build a new call to operator(). This may change ARGS. */
3331 tree
3333 {
3347 {
3349 /* It's no good looking for an overloaded operator() on a
3350 pointer-to-member-function. */
3351 error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
3353 }
3356 {
3360 }
3361 else
3365 {
3369 }
3371 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3375 {
3380 {
3389 else
3390 add_function_candidate
3393 }
3394 }
3399 {
3411 {
3418 add_template_conv_candidate
3422 else
3426 }
3427 }
3431 {
3433 {
3437 }
3439 }
3440 else
3441 {
3444 {
3446 {
3450 }
3452 }
3453 /* Since cand->fn will be a type, not a function, for a conversion
3454 function, we must be careful not to unconditionally look at
3455 DECL_NAME here. */
3459 else
3460 {
3462 complain);
3465 }
3466 }
3468 /* Free all the conversions we allocated. */
3472 }
3474 static void
3477 {
3482 else
3486 {
3491 else
3501 else
3510 else
3520 else
3530 else
3533 else
3537 else
3541 }
3542 }
3544 /* Return the implicit conversion sequence that could be used to
3545 convert E1 to E2 in [expr.cond]. */
3549 {
3555 /* [expr.cond]
3557 If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
3558 implicitly converted (clause _conv_) to the type "reference to
3559 T2", subject to the constraint that in the conversion the
3560 reference must bind directly (_dcl.init.ref_) to E1. */
3562 {
3564 t1,
3565 e1,
3570 }
3572 /* [expr.cond]
3574 If E1 and E2 have class type, and the underlying class types are
3575 the same or one is a base class of the other: E1 can be converted
3576 to match E2 if the class of T2 is the same type as, or a base
3577 class of, the class of T1, and the cv-qualification of T2 is the
3578 same cv-qualification as, or a greater cv-qualification than, the
3579 cv-qualification of T1. If the conversion is applied, E1 is
3580 changed to an rvalue of type T2 that still refers to the original
3581 source class object (or the appropriate subobject thereof). */
3584 {
3586 {
3591 else
3594 }
3595 else
3597 }
3598 else
3599 /* [expr.cond]
3601 Otherwise: E1 can be converted to match E2 if E1 can be implicitly
3602 converted to the type that expression E2 would have if E2 were
3603 converted to an rvalue (or the type it has, if E2 is an rvalue). */
3605 LOOKUP_IMPLICIT);
3606 }
3608 /* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
3609 arguments to the conditional expression. */
3611 tree
3613 tsubst_flags_t complain)
3614 {
3615 tree arg2_type;
3616 tree arg3_type;
3618 tree result_save;
3625 /* As a G++ extension, the second argument to the conditional can be
3626 omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
3627 c'.) If the second operand is omitted, make sure it is
3628 calculated only once. */
3630 {
3635 /* Make sure that lvalues remain lvalues. See g++.oliva/ext1.C. */
3638 else
3640 }
3642 /* [expr.cond]
3644 The first expression is implicitly converted to bool (clause
3645 _conv_). */
3647 LOOKUP_NORMAL);
3649 /* If something has already gone wrong, just pass that fact up the
3650 tree. */
3656 /* [expr.cond]
3658 If either the second or the third operand has type (possibly
3659 cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
3660 array-to-pointer (_conv.array_), and function-to-pointer
3661 (_conv.func_) standard conversions are performed on the second
3662 and third operands. */
3666 {
3667 /* Do the conversions. We don't these for `void' type arguments
3668 since it can't have any effect and since decay_conversion
3669 does not handle that case gracefully. */
3677 /* [expr.cond]
3679 One of the following shall hold:
3681 --The second or the third operand (but not both) is a
3682 throw-expression (_except.throw_); the result is of the
3683 type of the other and is an rvalue.
3685 --Both the second and the third operands have type void; the
3686 result is of type void and is an rvalue.
3688 We must avoid calling force_rvalue for expressions of type
3689 "void" because it will complain that their value is being
3690 used. */
3693 {
3698 }
3701 {
3706 }
3709 else
3710 {
3712 {
3715 "is of type %<void%>, "
3716 "but the third operand is neither a throw-expression "
3718 else
3720 "is of type %<void%>, "
3721 "but the second operand is neither a throw-expression "
3723 }
3725 }
3729 }
3730 /* [expr.cond]
3732 Otherwise, if the second and third operand have different types,
3733 and either has (possibly cv-qualified) class type, an attempt is
3734 made to convert each of those operands to the type of the other. */
3737 {
3741 /* Get the high-water mark for the CONVERSION_OBSTACK. */
3747 /* [expr.cond]
3749 If both can be converted, or one can be converted but the
3750 conversion is ambiguous, the program is ill-formed. If
3751 neither can be converted, the operands are left unchanged and
3752 further checking is performed as described below. If exactly
3753 one conversion is possible, that conversion is applied to the
3754 chosen operand and the converted operand is used in place of
3755 the original operand for the remainder of this section. */
3760 {
3764 }
3766 {
3770 /* Even if CONV2 is a valid conversion, the result of the
3771 conversion may be invalid. For example, if ARG3 has type
3772 "volatile X", and X does not have a copy constructor
3773 accepting a "volatile X&", then even if ARG2 can be
3774 converted to X, the conversion will fail. */
3777 }
3779 {
3785 }
3787 /* Free all the conversions we allocated. */
3793 /* If, after the conversion, both operands have class type,
3794 treat the cv-qualification of both operands as if it were the
3795 union of the cv-qualification of the operands.
3797 The standard is not clear about what to do in this
3798 circumstance. For example, if the first operand has type
3799 "const X" and the second operand has a user-defined
3800 conversion to "volatile X", what is the type of the second
3801 operand after this step? Making it be "const X" (matching
3802 the first operand) seems wrong, as that discards the
3803 qualification without actually performing a copy. Leaving it
3804 as "volatile X" seems wrong as that will result in the
3805 conditional expression failing altogether, even though,
3806 according to this step, the one operand could be converted to
3807 the type of the other. */
3815 }
3817 /* [expr.cond]
3819 If the second and third operands are lvalues and have the same
3820 type, the result is of that type and is an lvalue. */
3824 {
3827 }
3829 /* [expr.cond]
3831 Otherwise, the result is an rvalue. If the second and third
3832 operand do not have the same type, and either has (possibly
3833 cv-qualified) class type, overload resolution is used to
3834 determine the conversions (if any) to be applied to the operands
3835 (_over.match.oper_, _over.built_). */
3839 {
3844 /* Rearrange the arguments so that add_builtin_candidate only has
3845 to know about two args. In build_builtin_candidate, the
3846 arguments are unscrambled. */
3851 COND_EXPR,
3852 NOP_EXPR,
3854 args,
3855 LOOKUP_NORMAL);
3857 /* [expr.cond]
3859 If the overload resolution fails, the program is
3860 ill-formed. */
3863 {
3865 {
3868 }
3870 }
3873 {
3875 {
3878 }
3880 }
3882 /* [expr.cond]
3884 Otherwise, the conversions thus determined are applied, and
3885 the converted operands are used in place of the original
3886 operands for the remainder of this section. */
3895 }
3897 /* [expr.cond]
3899 Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
3900 and function-to-pointer (_conv.func_) standard conversions are
3901 performed on the second and third operands.
3903 We need to force the lvalue-to-rvalue conversion here for class types,
3904 so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
3905 that isn't wrapped with a TARGET_EXPR plays havoc with exception
3906 regions. */
3919 /* [expr.cond]
3921 After those conversions, one of the following shall hold:
3923 --The second and third operands have the same type; the result is of
3924 that type. */
3927 /* [expr.cond]
3929 --The second and third operands have arithmetic or enumeration
3930 type; the usual arithmetic conversions are performed to bring
3931 them to a common type, and the result is of that type. */
3936 {
3937 /* In this case, there is always a common type. */
3939 arg3_type);
3943 {
3948 }
3954 {
3958 }
3962 }
3963 /* [expr.cond]
3965 --The second and third operands have pointer type, or one has
3966 pointer type and the other is a null pointer constant; pointer
3967 conversions (_conv.ptr_) and qualification conversions
3968 (_conv.qual_) are performed to bring them to their composite
3969 pointer type (_expr.rel_). The result is of the composite
3970 pointer type.
3972 --The second and third operands have pointer to member type, or
3973 one has pointer to member type and the other is a null pointer
3974 constant; pointer to member conversions (_conv.mem_) and
3975 qualification conversions (_conv.qual_) are performed to bring
3976 them to a common type, whose cv-qualification shall match the
3977 cv-qualification of either the second or the third operand.
3978 The result is of the common type. */
3986 {
3989 complain);
3994 }
3997 {
4002 }
4004 valid_operands:
4009 /* Avoid folding to a CALL_EXPR within decltype (c++/42013). */
4012 /* We can't use result_type below, as fold might have returned a
4013 throw_expr. */
4016 {
4017 /* Expand both sides into the same slot, hopefully the target of
4018 the ?: expression. We used to check for TARGET_EXPRs here,
4019 but now we sometimes wrap them in NOP_EXPRs so the test would
4020 fail. */
4023 /* If this expression is an rvalue, but might be mistaken for an
4024 lvalue, we must add a NON_LVALUE_EXPR. */
4026 }
4029 }
4031 /* OPERAND is an operand to an expression. Perform necessary steps
4032 required before using it. If OPERAND is NULL_TREE, NULL_TREE is
4033 returned. */
4035 static tree
4037 {
4039 {
4042 /* Make sure the template type is instantiated now. */
4044 }
4047 }
4049 /* Add each of the viable functions in FNS (a FUNCTION_DECL or
4050 OVERLOAD) to the CANDIDATES, returning an updated list of
4051 CANDIDATES. The ARGS are the arguments provided to the call,
4052 without any implicit object parameter. This may change ARGS. The
4053 EXPLICIT_TARGS are explicit template arguments provided.
4054 TEMPLATE_ONLY is true if only template functions should be
4055 considered. CONVERSION_PATH, ACCESS_PATH, and FLAGS are as for
4056 add_function_candidate. */
4058 static void
4064 {
4065 tree ctype;
4067 tree first_arg;
4070 /* Delay creating the implicit this parameter until it is needed. */
4075 {
4076 tree fn;
4077 tree fn_first_arg;
4081 /* Figure out which set of arguments to use. */
4083 {
4084 /* If this function is a non-static member, prepend the implicit
4085 object parameter. */
4087 {
4089 tree arg;
4095 }
4100 }
4101 else
4102 {
4103 /* Otherwise, just use the list of arguments provided. */
4106 }
4110 fn,
4111 ctype,
4112 explicit_targs,
4113 fn_first_arg,
4114 fn_args,
4115 NULL_TREE,
4116 access_path,
4117 conversion_path,
4118 flags,
4119 DEDUCE_CALL);
4122 fn,
4123 ctype,
4124 fn_first_arg,
4125 fn_args,
4126 access_path,
4127 conversion_path,
4128 flags);
4130 }
4131 }
4133 /* Even unsigned enum types promote to signed int. We don't want to
4134 issue -Wsign-compare warnings for this case. Here ORIG_ARG is the
4135 original argument and ARG is the argument after any conversions
4136 have been applied. We set TREE_NO_WARNING if we have added a cast
4137 from an unsigned enum type to a signed integer type. */
4139 static void
4141 {
4150 }
4152 tree
4155 {
4161 tree fnname;
4179 {
4183 }
4184 else
4190 {
4195 /* Use build_op_new_call and build_op_delete_call instead. */
4199 /* Use build_op_call instead. */
4206 /* These are saved for the sake of warn_logical_operator. */
4212 }
4218 /* Use build_conditional_expr instead. */
4234 /* Get the high-water mark for the CONVERSION_OBSTACK. */
4237 /* Add namespace-scope operators to the list of functions to
4238 consider. */
4242 /* Add class-member operators to the candidate set. */
4244 {
4245 tree fns;
4249 {
4252 }
4259 }
4268 {
4271 /* For these, the built-in candidates set is empty
4272 [over.match.oper]/3. We don't want non-strict matches
4273 because exact matches are always possible with built-in
4274 operators. The built-in candidate set for COMPONENT_REF
4275 would be empty too, but since there are no such built-in
4276 operators, we accept non-strict matches for them. */
4283 }
4287 {
4289 {
4292 /* Don't try anything fancy if we're not allowed to produce
4293 errors. */
4297 /* Look for an `operator++ (int)'. Pre-1985 C++ didn't
4298 distinguish between prefix and postfix ++ and
4299 operator++() was used for both, so we allow this with
4300 -fpermissive. */
4302 {
4309 }
4316 else
4322 /* The caller will deal with these. */
4332 {
4333 /* If one of the arguments of the operator represents
4334 an invalid use of member function pointer, try to report
4335 a meaningful error ... */
4340 else
4341 {
4342 /* ... Otherwise, report the more generic
4343 "no matching operator found" error */
4346 }
4347 }
4350 }
4351 }
4352 else
4353 {
4356 {
4358 {
4361 }
4363 }
4365 {
4371 else
4373 }
4374 else
4375 {
4376 /* Give any warnings we noticed during overload resolution. */
4378 {
4382 }
4384 /* Check for comparison of different enum types. */
4386 {
4398 {
4402 }
4406 }
4408 /* We need to strip any leading REF_BIND so that bitfields
4409 don't cause errors. This should not remove any important
4410 conversions, because builtins don't apply to class
4411 objects directly. */
4418 {
4419 /* We need to call warn_logical_operator before
4420 converting arg2 to a boolean_type. */
4430 }
4432 {
4437 }
4439 }
4440 }
4442 user_defined_result_ready:
4444 /* Free all the conversions we allocated. */
4450 builtin:
4456 {
4469 /* Fall through. */
4507 complain),
4508 arg2);
4510 /* The caller will deal with these. */
4518 }
4520 }
4522 /* Returns true iff T, an element of an OVERLOAD chain, is a usual
4523 deallocation function (3.7.4.2 [basic.stc.dynamic.deallocation]). */
4525 static bool
4527 {
4528 /* A template instance is never a usual deallocation function,
4529 regardless of its signature. */
4534 /* If a class T has a member deallocation function named operator delete
4535 with exactly one parameter, then that function is a usual
4536 (non-placement) deallocation function. If class T does not declare
4537 such an operator delete but does declare a member deallocation
4538 function named operator delete with exactly two parameters, the second
4539 of which has type std::size_t (18.2), then this function is a usual
4540 deallocation function. */
4547 }
4549 /* Build a call to operator delete. This has to be handled very specially,
4550 because the restrictions on what signatures match are different from all
4551 other call instances. For a normal delete, only a delete taking (void *)
4552 or (void *, size_t) is accepted. For a placement delete, only an exact
4553 match with the placement new is accepted.
4555 CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
4556 ADDR is the pointer to be deleted.
4557 SIZE is the size of the memory block to be deleted.
4558 GLOBAL_P is true if the delete-expression should not consider
4559 class-specific delete operators.
4560 PLACEMENT is the corresponding placement new call, or NULL_TREE.
4562 If this call to "operator delete" is being generated as part to
4563 deallocate memory allocated via a new-expression (as per [expr.new]
4564 which requires that if the initialization throws an exception then
4565 we call a deallocation function), then ALLOC_FN is the allocation
4566 function. */
4568 tree
4571 tree alloc_fn)
4572 {
4586 /* In [class.free]
4588 If the result of the lookup is ambiguous or inaccessible, or if
4589 the lookup selects a placement deallocation function, the
4590 program is ill-formed.
4592 Therefore, we ask lookup_fnfields to complain about ambiguity. */
4593 {
4597 }
4598 else
4604 /* Strip const and volatile from addr. */
4608 {
4609 /* "A declaration of a placement deallocation function matches the
4610 declaration of a placement allocation function if it has the same
4611 number of parameters and, after parameter transformations (8.3.5),
4612 all parameter types except the first are identical."
4614 So we build up the function type we want and ask instantiate_type
4615 to get it for us. */
4627 /* "If the lookup finds the two-parameter form of a usual deallocation
4628 function (3.7.4.2) and that function, considered as a placement
4629 deallocation function, would have been selected as a match for the
4630 allocation function, the program is ill-formed." */
4632 {
4633 /* But if the class has an operator delete (void *), then that is
4634 the usual deallocation function, so we shouldn't complain
4635 about using the operator delete (void *, size_t). */
4638 {
4643 }
4646 ok:;
4647 }
4648 }
4649 else
4650 /* "Any non-placement deallocation function matches a non-placement
4651 allocation function. If the lookup finds a single matching
4652 deallocation function, that function will be called; otherwise, no
4653 deallocation function will be called." */
4656 {
4659 {
4661 /* "If a class T has a member deallocation function named
4662 operator delete with exactly one parameter, then that
4663 function is a usual (non-placement) deallocation
4664 function. If class T does not declare such an operator
4665 delete but does declare a member deallocation function named
4666 operator delete with exactly two parameters, the second of
4667 which has type std::size_t (18.2), then this function is a
4668 usual deallocation function."
4670 So (void*) beats (void*, size_t). */
4673 }
4674 }
4676 /* If we have a matching function, call it. */
4678 {
4681 /* If the FN is a member function, make sure that it is
4682 accessible. */
4686 /* Core issue 901: It's ok to new a type with deleted delete. */
4691 {
4692 /* The placement args might not be suitable for overload
4693 resolution at this point, so build the call directly. */
4702 }
4703 else
4704 {
4705 tree ret;
4713 }
4714 }
4716 /* [expr.new]
4718 If no unambiguous matching deallocation function can be found,
4719 propagating the exception does not cause the object's memory to
4720 be freed. */
4722 {
4725 alloc_fn);
4727 }
4732 }
4734 /* If the current scope isn't allowed to access DECL along
4735 BASETYPE_PATH, give an error. The most derived class in
4736 BASETYPE_PATH is the one used to qualify DECL. DIAG_DECL is
4737 the declaration to use in the error diagnostic. */
4739 bool
4741 {
4745 {
4750 else
4754 }
4757 }
4759 /* Initialize a temporary of type TYPE with EXPR. The FLAGS are a
4760 bitwise or of LOOKUP_* values. If any errors are warnings are
4761 generated, set *DIAGNOSTIC_FN to "error" or "warning",
4762 respectively. If no diagnostics are generated, set *DIAGNOSTIC_FN
4763 to NULL. */
4765 static tree
4768 {
4781 else
4784 }
4786 /* Perform warnings about peculiar, but valid, conversions from/to NULL.
4787 EXPR is implicitly converted to type TOTYPE.
4788 FN and ARGNUM are used for diagnostics. */
4790 static void
4792 {
4795 /* Issue warnings about peculiar, but valid, uses of NULL. */
4797 {
4802 else
4805 }
4807 /* Issue warnings if "false" is converted to a NULL pointer */
4812 }
4814 /* Perform the conversions in CONVS on the expression EXPR. FN and
4815 ARGNUM are used for diagnostics. ARGNUM is zero based, -1
4816 indicates the `this' argument of a method. INNER is nonzero when
4817 being called to continue a conversion chain. It is negative when a
4818 reference binding will be applied, positive otherwise. If
4819 ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
4820 conversions will be emitted if appropriate. If C_CAST_P is true,
4821 this conversion is coming from a C-style cast; in that case,
4822 conversions to inaccessible bases are permitted. */
4824 static tree
4828 {
4830 diagnostic_t diag_kind;
4840 {
4843 /* Give a helpful error if this is bad because of excess braces. */
4851 {
4853 {
4857 complain);
4859 }
4864 complain);
4867 }
4869 {
4873 }
4874 else
4878 }
4884 {
4886 {
4891 /* When converting from an init list we consider explicit
4892 constructors, but actually trying to call one is an error. */
4894 {
4898 else
4900 }
4902 /* Set user_conv_p on the argument conversions, so rvalue/base
4903 handling knows not to allow any more UDCs. */
4909 /* If this is a constructor or a function returning an aggr type,
4910 we need to build up a TARGET_EXPR. */
4912 {
4915 /* Remember that this was list-initialization. */
4918 }
4921 }
4924 {
4930 else
4932 }
4936 /* Convert a constant to its underlying value, unless we are
4937 about to bind it to a reference, in which case we need to
4938 leave it as an lvalue. */
4940 {
4943 /* If __null has been converted to an integer type, we do not
4944 want to warn about uses of EXPR as an integer, rather than
4945 as a pointer. */
4947 }
4952 /* Call build_user_type_conversion again for the error. */
4953 return build_user_type_conversion
4957 {
4958 /* Conversion to std::initializer_list<T>. */
4966 /* Convert all the elements. */
4968 {
4975 }
4976 /* Build up the array. */
4977 elttype = cp_build_qualified_type
4985 /* Call the private constructor. */
4987 new_ctor = build_special_member_call
4992 }
4999 };
5004 c_cast_p,
5005 complain);
5010 {
5015 /* Else fall through. */
5018 {
5019 /* We are going to bind a reference directly to a base-class
5020 subobject of EXPR. */
5021 /* Build an expression for `*((base*) &expr)'. */
5027 }
5029 /* Copy-initialization where the cv-unqualified version of the source
5030 type is the same class as, or a derived class of, the class of the
5031 destination [is treated as direct-initialization]. [dcl.init] */
5034 /* This conversion is being done in the context of a user-defined
5035 conversion (i.e. the second step of copy-initialization), so
5036 don't allow any more. */
5040 {
5046 }
5050 {
5055 {
5057 {
5062 }
5064 }
5066 /* If necessary, create a temporary.
5068 VA_ARG_EXPR and CONSTRUCTOR expressions are special cases
5069 that need temporaries, even when their types are reference
5070 compatible with the type of reference being bound, so the
5071 upcoming call to cp_build_unary_op (ADDR_EXPR, expr, ...)
5072 doesn't fail. */
5076 {
5082 {
5084 {
5085 /* If the reference is volatile or non-const, we
5086 cannot create a temporary. */
5093 else
5095 }
5097 }
5098 /* If the source is a packed field, and we must use a copy
5099 constructor, then building the target expr will require
5100 binding the field to the reference parameter to the
5101 copy constructor, and we'll end up with an infinite
5102 loop. If we can use a bitwise copy, then we'll be
5103 OK. */
5107 {
5112 }
5114 {
5117 }
5119 }
5121 /* Take the address of the thing to which we will bind the
5122 reference. */
5127 /* Convert it to a pointer to the type referred to by the
5128 reference. This will adjust the pointer if a derived to
5129 base conversion is being performed. */
5131 expr);
5132 /* Convert the pointer to the desired reference type. */
5134 }
5140 /* Warn about deprecated conversion if appropriate. */
5152 c_cast_p);
5156 }
5163 else
5167 }
5169 /* ARG is being passed to a varargs function. Perform any conversions
5170 required. Return the converted value. */
5172 tree
5174 {
5175 /* [expr.call]
5177 The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5178 standard conversions are performed. */
5180 /* [expr.call]
5182 If the argument has integral or enumeration type that is subject
5183 to the integral promotions (_conv.prom_), or a floating point
5184 type that is subject to the floating point promotion
5185 (_conv.fpprom_), the value of the argument is converted to the
5186 promoted type before the call. */
5200 {
5201 /* [expr.call] 5.2.2/7:
5202 Passing a potentially-evaluated argument of class type (Clause 9)
5203 with a non-trivial copy constructor or a non-trivial destructor
5204 with no corresponding parameter is conditionally-supported, with
5205 implementation-defined semantics.
5207 We used to just warn here and do a bitwise copy, but now
5208 cp_expr_size will abort if we try to do that.
5210 If the call appears in the context of a sizeof expression,
5211 it is not potentially-evaluated. */
5215 }
5218 }
5220 /* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
5222 tree
5224 {
5236 {
5237 /* Remove reference types so we don't ICE later on. */
5239 /* conditionally-supported behavior [expr.call] 5.2.2/7. */
5245 }
5248 }
5250 /* TYPE has been given to va_arg. Apply the default conversions which
5251 would have happened when passed via ellipsis. Return the promoted
5252 type, or the passed type if there is no change. */
5254 tree
5256 {
5257 tree promote;
5259 /* Perform the array-to-pointer and function-to-pointer
5260 conversions. */
5268 }
5270 /* ARG is a default argument expression being passed to a parameter of
5271 the indicated TYPE, which is a parameter to FN. Do any required
5272 conversions. Return the converted value. */
5276 tree
5278 {
5280 tree t;
5282 /* If the ARG is an unparsed default argument expression, the
5283 conversion cannot be performed. */
5285 {
5290 }
5292 /* Detect recursion. */
5295 {
5298 }
5304 /* Due to:
5306 [dcl.fct.default]
5308 The names in the expression are bound, and the semantic
5309 constraints are checked, at the point where the default
5310 expressions appears.
5312 we must not perform access checks here. */
5316 {
5320 tf_warning_or_error);
5321 }
5322 else
5323 {
5324 /* We must make a copy of ARG, in case subsequent processing
5325 alters any part of it. For example, during gimplification a
5326 cast of the form (T) &X::f (where "f" is a member function)
5327 will lead to replacing the PTRMEM_CST for &X::f with a
5328 VAR_DECL. We can avoid the copy for constants, since they
5329 are never modified in place. */
5334 tf_warning_or_error);
5336 }
5342 }
5344 /* Returns the type which will really be used for passing an argument of
5345 type TYPE. */
5347 tree
5349 {
5350 /* Pass classes with copy ctors by invisible reference. */
5352 {
5354 /* There are no other pointers to this temporary. */
5356 }
5365 }
5367 /* Actually perform the appropriate conversion. */
5369 tree
5371 {
5372 tree bitfield_type;
5374 /* If VAL is a bitfield, then -- since it has already been converted
5375 to TYPE -- it cannot have a precision greater than TYPE.
5377 If it has a smaller precision, we must widen it here. For
5378 example, passing "int f:3;" to a function expecting an "int" will
5379 not result in any conversion before this point.
5381 If the precision is the same we must not risk widening. For
5382 example, the COMPONENT_REF for a 32-bit "long long" bitfield will
5383 often have type "int", even though the C++ type for the field is
5384 "long long". If the value is being passed to a function
5385 expecting an "int", then no conversions will be required. But,
5386 if we call convert_bitfield_to_declared_type, the bitfield will
5387 be converted to "long long". */
5394 ;
5395 /* Pass classes with copy ctors by invisible reference. */
5405 {
5414 }
5416 }
5418 /* Returns true iff FN is a function with magic varargs, i.e. ones for
5419 which no conversions at all should be done. This is true for some
5420 builtins which don't act like normal functions. */
5422 static bool
5424 {
5427 {
5437 }
5440 }
5442 /* Subroutine of the various build_*_call functions. Overload resolution
5443 has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
5444 ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
5445 bitmask of various LOOKUP_* flags which apply to the call itself. */
5447 static tree
5449 {
5457 tree val;
5466 /* In a template, there is no need to perform all of the work that
5467 is normally done. We are only interested in the type of the call
5468 expression, i.e., the return type of the function. Any semantic
5469 errors will be deferred until the template is instantiated. */
5471 {
5472 tree expr;
5473 tree return_type;
5481 else
5482 {
5485 tree arg;
5493 }
5496 argarray);
5502 }
5504 /* Give any warnings we noticed during overload resolution. */
5506 {
5510 }
5512 /* Make =delete work with SFINAE. */
5517 {
5518 /* If FN is a template function, two cases must be considered.
5519 For example:
5521 struct A {
5522 protected:
5523 template <class T> void f();
5524 };
5525 template <class T> struct B {
5526 protected:
5527 void g();
5528 };
5529 struct C : A, B<int> {
5530 using A::f; // #1
5531 using B<int>::g; // #2
5532 };
5534 In case #1 where `A::f' is a member template, DECL_ACCESS is
5535 recorded in the primary template but not in its specialization.
5536 We check access of FN using its primary template.
5538 In case #2, where `B<int>::g' has a DECL_TEMPLATE_INFO simply
5539 because it is a member of class template B, DECL_ACCESS is
5540 recorded in the specialization `B<int>::g'. We cannot use its
5541 primary template because `B<T>::g' and `B<int>::g' may have
5542 different access. */
5547 else
5549 }
5551 /* Find maximum size of vector to hold converted arguments. */
5558 /* The implicit parameters to a constructor are not considered by overload
5559 resolution, and must be of the proper type. */
5561 {
5563 {
5566 }
5567 else
5568 {
5571 }
5573 /* We should never try to call the abstract constructor. */
5577 {
5581 }
5582 }
5583 /* Bypass access control for 'this' parameter. */
5585 {
5588 ? first_arg
5591 tree converted_arg;
5592 tree base_binfo;
5595 {
5599 else
5601 }
5603 /* [class.mfct.nonstatic]: If a nonstatic member function of a class
5604 X is called for an object that is not of type X, or of a type
5605 derived from X, the behavior is undefined.
5607 So we can assume that anything passed as 'this' is non-null, and
5608 optimize accordingly. */
5610 /* Convert to the base in which the function was declared. */
5613 arg,
5616 /* Check that the base class is accessible. */
5622 /* If fn was found by a using declaration, the conversion path
5623 will be to the derived class, not the base declaring fn. We
5624 must convert from derived to base. */
5634 else
5638 }
5643 {
5648 /* Don't make a copy here if build_call is going to. */
5654 /* Warn about initializer_list deduction that isn't currently in the
5655 working draft. */
5657 && flag_deduce_init_list
5660 {
5670 {
5677 }
5678 }
5680 val = convert_like_with_context
5682 complain);
5687 else
5689 }
5691 /* Default arguments */
5696 /* Ellipsis */
5698 {
5702 else
5705 }
5713 /* Avoid actually calling copy constructors and copy assignment operators,
5714 if possible. */
5721 {
5722 tree targ;
5724 tree fa;
5726 /* Pull out the real argument, disregarding const-correctness. */
5732 {
5737 }
5738 else
5743 else
5748 {
5749 /* Copy-list-initialization doesn't require the copy constructor
5750 to be defined. */
5751 }
5752 /* [class.copy]: the copy constructor is implicitly defined even if
5753 the implementation elided its use. */
5755 {
5758 }
5760 /* If we're creating a temp and we already have one, don't create a
5761 new one. If we're not creating a temp but we get one, use
5762 INIT_EXPR to collapse the temp into our target. Otherwise, if the
5763 ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
5764 temp or an INIT_EXPR otherwise. */
5769 {
5774 }
5778 {
5780 complain));
5784 }
5785 }
5789 {
5790 tree to = stabilize_reference
5797 {
5798 /* Avoid copying empty classes. */
5803 }
5805 {
5808 }
5809 else
5810 {
5811 /* We must only copy the non-tail padding parts.
5812 Use __builtin_memcpy for the bitwise copy.
5813 FIXME fix 22488 so we can go back to using MODIFY_EXPR
5814 instead of an explicit call to memcpy. */
5824 {
5825 /* If we can't be sure about pointer alignment, a call
5826 to __builtin_memcpy is expanded as a call to memcpy, which
5827 is invalid with identical args. Otherwise it is
5828 expanded as a block move, which should be safe. */
5832 }
5841 }
5844 }
5850 {
5851 tree t;
5857 /* Warn about deprecated virtual functions now, since we're about
5858 to throw away the decl. */
5868 else
5871 }
5872 else
5876 }
5878 /* Build and return a call to FN, using NARGS arguments in ARGARRAY.
5879 This function performs no overload resolution, conversion, or other
5880 high-level operations. */
5882 tree
5884 {
5885 tree fndecl;
5889 /* If this call might throw an exception, note that fact. */
5896 /* Check that arguments to builtin functions match the expectations. */
5903 /* Some built-in function calls will be evaluated at compile-time in
5904 fold (). */
5917 }
5921 /* Make an expression which yields the address of the Java interface
5922 method FN. This is achieved by generating a call to libjava's
5923 _Jv_LookupInterfaceMethodIdx(). */
5925 static tree
5927 {
5933 {
5938 endlink)));
5939 java_iface_lookup_fn
5943 }
5945 /* Look up the pointer to the runtime java.lang.Class object for `instance'.
5946 This is the first entry in the vtable. */
5948 tf_warning_or_error),
5949 integer_zero_node);
5951 /* Get the java.lang.Class pointer for the interface being called. */
5956 {
5958 iface);
5960 }
5964 /* Determine the itable index of FN. */
5967 {
5972 i++;
5973 }
5978 java_iface_lookup_fn);
5981 }
5983 /* Returns the value to use for the in-charge parameter when making a
5984 call to a function with the indicated NAME.
5986 FIXME:Can't we find a neater way to do this mapping? */
5988 tree
5990 {
6001 /* This function should only be called with one of the names listed
6002 above. */
6005 }
6007 /* Build a call to a constructor, destructor, or an assignment
6008 operator for INSTANCE, an expression with class type. NAME
6009 indicates the special member function to call; *ARGS are the
6010 arguments. ARGS may be NULL. This may change ARGS. BINFO
6011 indicates the base of INSTANCE that is to be passed as the `this'
6012 parameter to the member function called.
6014 FLAGS are the LOOKUP_* flags to use when processing the call.
6016 If NAME indicates a complete object constructor, INSTANCE may be
6017 NULL_TREE. In this case, the caller will call build_cplus_new to
6018 store the newly constructed object into a VAR_DECL. */
6020 tree
6023 {
6024 tree fns;
6025 /* The type of the subobject to be constructed or destroyed. */
6026 tree class_type;
6028 tree ret;
6037 {
6038 /* Resolve the name. */
6043 }
6049 /* Handle the special case where INSTANCE is NULL_TREE. */
6051 {
6054 }
6055 else
6056 {
6062 /* Convert to the base class, if necessary. */
6065 {
6067 /* For constructors and destructors, either the base is
6068 non-virtual, or it is virtual but we are doing the
6069 conversion from a constructor or destructor for the
6070 complete object. In either case, we can convert
6071 statically. */
6073 else
6074 /* However, for assignment operators, we must convert
6075 dynamically if the base is virtual. */
6078 }
6079 }
6085 /* When making a call to a constructor or destructor for a subobject
6086 that uses virtual base classes, pass down a pointer to a VTT for
6087 the subobject. */
6091 {
6092 tree vtt;
6093 tree sub_vtt;
6095 /* If the current function is a complete object constructor
6096 or destructor, then we fetch the VTT directly.
6097 Otherwise, we look it up using the VTT we were given. */
6103 current_vtt_parm,
6104 vtt);
6110 {
6113 }
6116 }
6121 complain);
6127 }
6129 /* Return the NAME, as a C string. The NAME indicates a function that
6130 is a member of TYPE. *FREE_P is set to true if the caller must
6131 free the memory returned.
6133 Rather than go through all of this, we should simply set the names
6134 of constructors and destructors appropriately, and dispense with
6135 ctor_identifier, dtor_identifier, etc. */
6139 {
6142 /* Assume that we will not allocate memory. */
6144 /* Constructors and destructors are special. */
6146 {
6147 pretty_name
6149 /* For a destructor, add the '~'. */
6153 {
6155 /* Remember that we need to free the memory allocated. */
6157 }
6158 }
6160 {
6163 TFF_PLAIN_IDENTIFIER),
6164 NULL);
6165 /* Remember that we need to free the memory allocated. */
6167 }
6168 else
6172 }
6174 /* Build a call to "INSTANCE.FN (ARGS)". If FN_P is non-NULL, it will
6175 be set, upon return, to the function called. ARGS may be NULL.
6176 This may change ARGS. */
6178 tree
6182 {
6186 tree access_binfo;
6187 tree optype;
6189 tree instance_ptr;
6190 tree name;
6193 tree call;
6194 tree fn;
6195 tree class_type;
6198 tree orig_instance;
6199 tree orig_fns;
6205 /* We don't know what function we're going to call, yet. */
6214 {
6218 }
6223 /* Dismantle the baselink to collect all the information we need. */
6230 {
6234 }
6245 {
6250 }
6253 /* Under DR 147 A::A() is an invalid constructor call,
6254 not a functional cast. */
6256 {
6266 complain);
6268 }
6270 /* Figure out whether to skip the first argument for the error
6271 message we will display to users if an error occurs. We don't
6272 want to display any compiler-generated arguments. The "this"
6273 pointer hasn't been added yet. However, we must remove the VTT
6274 pointer if this is a call to a base-class constructor or
6275 destructor. */
6278 {
6279 /* Callers should explicitly indicate whether they want to construct
6280 the complete object or just the part without virtual bases. */
6282 /* Similarly for destructors. */
6284 /* Remove the VTT pointer, if present. */
6288 }
6290 /* Process the argument list. */
6292 {
6296 }
6300 /* It's OK to call destructors and constructors on cv-qualified objects.
6301 Therefore, convert the INSTANCE_PTR to the unqualified type, if
6302 necessary. */
6305 {
6309 }
6313 /* If CONSTRUCTOR_IS_DIRECT_INIT is set, this was a T{ } form
6314 initializer, not T({ }). If the type doesn't have a list ctor,
6315 break apart the list into separate ctor args. */
6320 {
6323 }
6328 /* Get the high-water mark for the CONVERSION_OBSTACK. */
6332 {
6334 tree this_first_arg;
6336 /* We can end up here for copy-init of same or base class. */
6343 else
6347 /* A member template. */
6349 class_type,
6350 explicit_targs,
6351 this_first_arg,
6353 optype,
6354 access_binfo,
6355 conversion_path,
6356 flags,
6357 DEDUCE_CALL);
6360 class_type,
6361 this_first_arg,
6363 access_binfo,
6364 conversion_path,
6365 flags);
6366 }
6370 {
6372 {
6375 else
6376 {
6379 tree arglist;
6390 }
6392 }
6394 }
6395 else
6396 {
6399 {
6402 tree arglist;
6405 {
6411 arglist);
6415 }
6417 }
6418 else
6419 {
6428 /* This is not an error, it is runtime undefined
6429 behavior. */
6431 "abstract virtual %q#D called from constructor"
6433 fn);
6437 {
6440 fn);
6442 }
6443 else
6444 {
6448 /* Now we know what function is being called. */
6451 /* Build the actual CALL_EXPR. */
6453 /* In an expression of the form `a->f()' where `f' turns
6454 out to be a static member function, `a' is
6455 none-the-less evaluated. */
6464 /* An explicit call of the form "x->~X()" has type
6465 "void". However, on platforms where destructors
6466 return "this" (i.e., those where
6467 targetm.cxx.cdtor_returns_this is true), such calls
6468 will appear to have a return value of pointer type
6469 to the low-level call machinery. We do not want to
6470 change the low-level machinery, since we want to be
6471 able to optimize "delete f()" on such platforms as
6472 "operator delete(~X(f()))" (rather than generating
6473 "t = f(), ~X(t), operator delete (t)"). */
6475 }
6476 }
6477 }
6480 {
6486 {
6489 }
6492 call = (build_min_non_dep_call_vec
6496 orig_args));
6500 }
6502 /* Free all the conversions we allocated. */
6509 }
6511 /* Returns true iff standard conversion sequence ICS1 is a proper
6512 subsequence of ICS2. */
6514 static bool
6516 {
6517 /* We can assume that a conversion of the same code
6518 between the same types indicates a subsequence since we only get
6519 here if the types we are converting from are the same. */
6526 {
6534 /* At this point, ICS1 cannot be a proper subsequence of
6535 ICS2. We can get a USER_CONV when we are comparing the
6536 second standard conversion sequence of two user conversion
6537 sequences. */
6547 }
6548 }
6550 /* Returns nonzero iff DERIVED is derived from BASE. The inputs may
6551 be any _TYPE nodes. */
6553 bool
6555 {
6559 /* We only allow proper derivation here. The DERIVED_FROM_P macro
6560 considers every class derived from itself. */
6563 }
6565 /* We build the ICS for an implicit object parameter as a pointer
6566 conversion sequence. However, such a sequence should be compared
6567 as if it were a reference conversion sequence. If ICS is the
6568 implicit conversion sequence for an implicit object parameter,
6569 modify it accordingly. */
6571 static void
6573 {
6575 {
6576 /* [over.match.funcs]
6578 For non-static member functions, the type of the
6579 implicit object parameter is "reference to cv X"
6580 where X is the class of which the function is a
6581 member and cv is the cv-qualification on the member
6582 function declaration. */
6584 tree reference_type;
6586 /* The `this' parameter is a pointer to a class type. Make the
6587 implicit conversion talk about a reference to that same class
6588 type. */
6601 }
6602 }
6604 /* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
6605 and return the initial reference binding conversion. Otherwise,
6606 leave *ICS unchanged and return NULL. */
6610 {
6612 {
6617 }
6620 }
6622 /* Compare two implicit conversion sequences according to the rules set out in
6623 [over.ics.rank]. Return values:
6625 1: ics1 is better than ics2
6626 -1: ics2 is better than ics1
6627 0: ics1 and ics2 are indistinguishable */
6629 static int
6631 {
6632 tree from_type1;
6633 tree from_type2;
6634 tree to_type1;
6635 tree to_type2;
6642 /* REF_BINDING is nonzero if the result of the conversion sequence
6643 is a reference type. In that case REF_CONV is the reference
6644 binding conversion. */
6648 /* Handle implicit object parameters. */
6652 /* Handle reference parameters. */
6656 /* List-initialization sequence L1 is a better conversion sequence than
6657 list-initialization sequence L2 if L1 converts to
6658 std::initializer_list<X> for some X and L2 does not. */
6664 /* [over.ics.rank]
6666 When comparing the basic forms of implicit conversion sequences (as
6667 defined in _over.best.ics_)
6669 --a standard conversion sequence (_over.ics.scs_) is a better
6670 conversion sequence than a user-defined conversion sequence
6671 or an ellipsis conversion sequence, and
6673 --a user-defined conversion sequence (_over.ics.user_) is a
6674 better conversion sequence than an ellipsis conversion sequence
6675 (_over.ics.ellipsis_). */
6685 {
6686 /* XXX Isn't this an extension? */
6687 /* Both ICS are bad. We try to make a decision based on what
6688 would have happened if they'd been good. */
6696 /* We couldn't make up our minds; try to figure it out below. */
6697 }
6700 /* Both conversions are ellipsis conversions or both are building a
6701 std::initializer_list. */
6704 /* User-defined conversion sequence U1 is a better conversion sequence
6705 than another user-defined conversion sequence U2 if they contain the
6706 same user-defined conversion operator or constructor and if the sec-
6707 ond standard conversion sequence of U1 is better than the second
6708 standard conversion sequence of U2. */
6711 {
6725 /* We can just fall through here, after setting up
6726 FROM_TYPE1 and FROM_TYPE2. */
6729 }
6730 else
6731 {
6735 /* We're dealing with two standard conversion sequences.
6737 [over.ics.rank]
6739 Standard conversion sequence S1 is a better conversion
6740 sequence than standard conversion sequence S2 if
6742 --S1 is a proper subsequence of S2 (comparing the conversion
6743 sequences in the canonical form defined by _over.ics.scs_,
6744 excluding any Lvalue Transformation; the identity
6745 conversion sequence is considered to be a subsequence of
6746 any non-identity conversion sequence */
6757 }
6759 /* One sequence can only be a subsequence of the other if they start with
6760 the same type. They can start with different types when comparing the
6761 second standard conversion sequence in two user-defined conversion
6762 sequences. */
6764 {
6769 }
6771 /* [over.ics.rank]
6773 Or, if not that,
6775 --the rank of S1 is better than the rank of S2 (by the rules
6776 defined below):
6778 Standard conversion sequences are ordered by their ranks: an Exact
6779 Match is a better conversion than a Promotion, which is a better
6780 conversion than a Conversion.
6782 Two conversion sequences with the same rank are indistinguishable
6783 unless one of the following rules applies:
6785 --A conversion that is not a conversion of a pointer, or pointer
6786 to member, to bool is better than another conversion that is such
6787 a conversion.
6789 The ICS_STD_RANK automatically handles the pointer-to-bool rule,
6790 so that we do not have to check it explicitly. */
6799 /* A conversion from scalar arithmetic type to complex is worse than a
6800 conversion between scalar arithmetic types. */
6807 {
6810 else
6812 }
6818 {
6823 }
6824 /* The rules for pointers to members A::* are just like the rules
6825 for pointers A*, except opposite: if B is derived from A then
6826 A::* converts to B::*, not vice versa. For that reason, we
6827 switch the from_ and to_ variables here. */
6834 {
6839 }
6844 {
6845 /* This was one of the pointer or pointer-like conversions.
6847 [over.ics.rank]
6849 --If class B is derived directly or indirectly from class A,
6850 conversion of B* to A* is better than conversion of B* to
6851 void*, and conversion of A* to void* is better than
6852 conversion of B* to void*. */
6855 {
6857 deref_from_type2))
6860 deref_from_type1))
6862 }
6865 {
6867 {
6869 {
6871 deref_to_type1))
6873 }
6874 /* We know that DEREF_TO_TYPE1 is `void' here. */
6876 deref_to_type2))
6878 }
6879 }
6882 {
6883 /* [over.ics.rank]
6885 --If class B is derived directly or indirectly from class A
6886 and class C is derived directly or indirectly from B,
6888 --conversion of C* to B* is better than conversion of C* to
6889 A*,
6891 --conversion of B* to A* is better than conversion of C* to
6892 A* */
6894 {
6896 deref_to_type2))
6899 deref_to_type1))
6901 }
6903 {
6905 deref_from_type1))
6908 deref_from_type2))
6910 }
6911 }
6912 }
6915 {
6918 /* [over.ics.rank]
6920 --binding of an expression of type C to a reference of type
6921 B& is better than binding an expression of type C to a
6922 reference of type A&
6924 --conversion of C to B is better than conversion of C to A, */
6927 {
6932 }
6933 }
6936 {
6939 /* [over.ics.rank]
6941 --binding of an expression of type B to a reference of type
6942 A& is better than binding an expression of type C to a
6943 reference of type A&,
6945 --conversion of B to A is better than conversion of C to A */
6948 {
6953 }
6954 }
6956 /* [over.ics.rank]
6958 --S1 and S2 differ only in their qualification conversion and yield
6959 similar types T1 and T2 (_conv.qual_), respectively, and the cv-
6960 qualification signature of type T1 is a proper subset of the cv-
6961 qualification signature of type T2 */
6965 {
6969 }
6971 /* [over.ics.rank]
6973 --S1 and S2 are reference bindings (_dcl.init.ref_) and neither refers
6974 to an implicit object parameter, and either S1 binds an lvalue reference
6975 to an lvalue and S2 binds an rvalue reference or S1 binds an rvalue
6976 reference to an rvalue and S2 binds an lvalue reference
6977 (C++0x draft standard, 13.3.3.2)
6979 --S1 and S2 are reference bindings (_dcl.init.ref_), and the
6980 types to which the references refer are the same type except for
6981 top-level cv-qualifiers, and the type to which the reference
6982 initialized by S2 refers is more cv-qualified than the type to
6983 which the reference initialized by S1 refers */
6986 {
6990 {
6995 }
7000 }
7002 /* Neither conversion sequence is better than the other. */
7004 }
7006 /* The source type for this standard conversion sequence. */
7008 static tree
7010 {
7012 {
7017 }
7019 }
7021 /* Note a warning about preferring WINNER to LOSER. We do this by storing
7022 a pointer to LOSER and re-running joust to produce the warning if WINNER
7023 is actually used. */
7025 static void
7027 {
7033 }
7035 /* Compare two candidates for overloading as described in
7036 [over.match.best]. Return values:
7038 1: cand1 is better than cand2
7039 -1: cand2 is better than cand1
7040 0: cand1 and cand2 are indistinguishable */
7042 static int
7044 {
7050 /* Candidates that involve bad conversions are always worse than those
7051 that don't. */
7057 /* If we have two pseudo-candidates for conversions to the same type,
7058 or two candidates for the same function, arbitrarily pick one. */
7063 /* a viable function F1
7064 is defined to be a better function than another viable function F2 if
7065 for all arguments i, ICSi(F1) is not a worse conversion sequence than
7066 ICSi(F2), and then */
7068 /* for some argument j, ICSj(F1) is a better conversion sequence than
7069 ICSj(F2) */
7071 /* For comparing static and non-static member functions, we ignore
7072 the implicit object parameter of the non-static function. The
7073 standard says to pretend that the static function has an object
7074 parm, but that won't work with operator overloading. */
7077 {
7085 else
7086 {
7089 }
7090 }
7093 {
7099 {
7112 {
7119 else
7124 {
7128 }
7129 else
7131 }
7134 {
7137 }
7139 }
7140 }
7142 /* warn about confusing overload resolution for user-defined conversions,
7143 either between a constructor and a conversion op, or between two
7144 conversion ops. */
7148 {
7154 else
7157 /* We don't want to complain about `X::operator T1 ()'
7158 beating `X::operator T2 () const', when T2 is a no less
7159 cv-qualified version of T1. */
7162 {
7167 {
7170 }
7173 }
7174 else
7180 {
7187 {
7189 }
7190 }
7191 else
7193 }
7198 /* or, if not that,
7199 F1 is a non-template function and F2 is a template function
7200 specialization. */
7207 /* or, if not that,
7208 F1 and F2 are template functions and the function template for F1 is
7209 more specialized than the template for F2 according to the partial
7210 ordering rules. */
7213 {
7214 winner = more_specialized_fn
7217 /* [temp.func.order]: The presence of unused ellipsis and default
7218 arguments has no effect on the partial ordering of function
7219 templates. add_function_candidate() will not have
7220 counted the "this" argument for constructors. */
7224 }
7226 /* or, if not that,
7227 the context is an initialization by user-defined conversion (see
7228 _dcl.init_ and _over.match.user_) and the standard conversion
7229 sequence from the return type of F1 to the destination type (i.e.,
7230 the type of the entity being initialized) is a better conversion
7231 sequence than the standard conversion sequence from the return type
7232 of F2 to the destination type. */
7235 {
7239 }
7241 /* Check whether we can discard a builtin candidate, either because we
7242 have two identical ones or matching builtin and non-builtin candidates.
7244 (Pedantically in the latter case the builtin which matched the user
7245 function should not be added to the overload set, but we spot it here.
7247 [over.match.oper]
7248 ... the builtin candidates include ...
7249 - do not have the same parameter type list as any non-template
7250 non-member candidate. */
7254 {
7260 {
7262 /* Two built-in candidates; arbitrarily pick one. */
7265 /* cand1 is built-in; prefer cand2. */
7267 else
7268 /* cand2 is built-in; prefer cand1. */
7270 }
7271 }
7273 /* If the two function declarations represent the same function (this can
7274 happen with declarations in multiple scopes and arg-dependent lookup),
7275 arbitrarily choose one. But first make sure the default args we're
7276 using match. */
7279 {
7286 {
7287 /* Don't crash if the fn is variadic. */
7292 }
7300 {
7303 {
7305 {
7312 }
7313 else
7316 }
7319 }
7322 }
7324 tweak:
7326 /* Extension: If the worst conversion for one candidate is worse than the
7327 worst conversion for the other, take the first. */
7329 {
7334 {
7339 }
7345 {
7347 {
7349 "ISO C++ says that these are ambiguous, even "
7350 "though the worst conversion for the first is better than "
7354 }
7355 else
7358 }
7359 }
7363 }
7365 /* Given a list of candidates for overloading, find the best one, if any.
7366 This algorithm has a worst case of O(2n) (winner is last), and a best
7367 case of O(n/2) (totally ambiguous); much better than a sorting
7368 algorithm. */
7372 {
7377 /* Walk through the list once, comparing each current champ to the next
7378 candidate, knocking out a candidate or two with each comparison. */
7381 {
7385 else
7386 {
7388 {
7393 }
7394 else
7395 {
7398 }
7401 }
7402 }
7404 /* Make sure the champ is better than all the candidates it hasn't yet
7405 been compared to. */
7408 challenger != champ
7411 {
7415 }
7418 }
7420 /* Returns nonzero if things of type FROM can be converted to TO. */
7422 bool
7424 {
7426 }
7428 /* Returns nonzero if ARG (of type FROM) can be converted to TO. */
7430 bool
7432 {
7437 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7441 flags);
7444 /* Free all the conversions we allocated. */
7448 }
7450 /* Like can_convert_arg, but allows dubious conversions as well. */
7452 bool
7454 {
7458 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7460 /* Try to perform the conversion. */
7462 flags);
7463 /* Free all the conversions we allocated. */
7467 }
7469 /* Convert EXPR to TYPE. Return the converted expression.
7471 Note that we allow bad conversions here because by the time we get to
7472 this point we are committed to doing the conversion. If we end up
7473 doing a bad conversion, convert_like will complain. */
7475 tree
7477 {
7484 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7489 flags);
7492 {
7494 {
7495 /* If expr has unknown type, then it is an overloaded function.
7496 Call instantiate_type to get good error messages. */
7501 else
7503 }
7505 }
7507 {
7508 /* In a template, we are only concerned about determining the
7509 type of non-dependent expressions, so we do not have to
7510 perform the actual conversion. */
7513 }
7514 else
7517 /* Free all the conversions we allocated. */
7521 }
7523 tree
7525 {
7527 }
7529 /* Convert EXPR to TYPE (as a direct-initialization) if that is
7530 permitted. If the conversion is valid, the converted expression is
7531 returned. Otherwise, NULL_TREE is returned, except in the case
7532 that TYPE is a class type; in that case, an error is issued. If
7533 C_CAST_P is true, then this direction initialization is taking
7534 place as part of a static_cast being attempted as part of a C-style
7535 cast. */
7537 tree
7539 tree expr,
7541 tsubst_flags_t complain)
7542 {
7548 /* [dcl.init]
7550 If the destination type is a (possibly cv-qualified) class type:
7552 -- If the initialization is direct-initialization ...,
7553 constructors are considered. ... If no constructor applies, or
7554 the overload resolution is ambiguous, the initialization is
7555 ill-formed. */
7557 {
7563 }
7565 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7569 c_cast_p,
7570 LOOKUP_NORMAL);
7573 else
7576 c_cast_p,
7577 complain);
7579 /* Free all the conversions we allocated. */
7583 }
7585 /* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
7586 is being bound to a temporary. Create and return a new VAR_DECL
7587 with the indicated TYPE; this variable will store the value to
7588 which the reference is bound. */
7590 tree
7592 {
7593 tree var;
7595 /* Create the variable. */
7598 /* Register the variable. */
7600 {
7601 /* Namespace-scope or local static; give it a mangled name. */
7602 tree name;
7609 }
7610 else
7611 /* Create a new cleanup level if necessary. */
7615 }
7617 /* EXPR is the initializer for a variable DECL of reference or
7618 std::initializer_list type. Create, push and return a new VAR_DECL
7619 for the initializer so that it will live as long as DECL. Any
7620 cleanup for the new variable is returned through CLEANUP, and the
7621 code to initialize the new variable is returned through INITP. */
7623 tree
7625 {
7626 tree init;
7627 tree type;
7628 tree var;
7630 /* Create the temporary variable. */
7634 /* If the rvalue is the result of a function call it will be
7635 a TARGET_EXPR. If it is some other construct (such as a
7636 member access expression where the underlying object is
7637 itself the result of a function call), turn it into a
7638 TARGET_EXPR here. It is important that EXPR be a
7639 TARGET_EXPR below since otherwise the INIT_EXPR will
7640 attempt to make a bitwise copy of EXPR to initialize
7641 VAR. */
7644 /* Create the INIT_EXPR that will initialize the temporary
7645 variable. */
7648 {
7653 else
7656 /* We must be careful to destroy the temporary only
7657 after its initialization has taken place. If the
7658 initialization throws an exception, then the
7659 destructor should not be run. We cannot simply
7660 transform INIT into something like:
7662 (INIT, ({ CLEANUP_STMT; }))
7664 because emit_local_var always treats the
7665 initializer as a full-expression. Thus, the
7666 destructor would run too early; it would run at the
7667 end of initializing the reference variable, rather
7668 than at the end of the block enclosing the
7669 reference variable.
7671 The solution is to pass back a cleanup expression
7672 which the caller is responsible for attaching to
7673 the statement tree. */
7674 }
7675 else
7676 {
7680 static_aggregates);
7681 }
7685 }
7687 /* Convert EXPR to the indicated reference TYPE, in a way suitable for
7688 initializing a variable of that TYPE. If DECL is non-NULL, it is
7689 the VAR_DECL being initialized with the EXPR. (In that case, the
7690 type of DECL will be TYPE.) If DECL is non-NULL, then CLEANUP must
7691 also be non-NULL, and with *CLEANUP initialized to NULL. Upon
7692 return, if *CLEANUP is no longer NULL, it will be an expression
7693 that should be pushed as a cleanup after the returned expression
7694 is used to initialize DECL.
7696 Return the converted expression. */
7698 tree
7700 tsubst_flags_t complain)
7701 {
7708 /* Get the high-water mark for the CONVERSION_OBSTACK. */
7712 LOOKUP_NORMAL);
7714 {
7716 {
7723 else
7727 }
7729 }
7731 /* If DECL is non-NULL, then this special rule applies:
7733 [class.temporary]
7735 The temporary to which the reference is bound or the temporary
7736 that is the complete object to which the reference is bound
7737 persists for the lifetime of the reference.
7739 The temporaries created during the evaluation of the expression
7740 initializing the reference, except the temporary to which the
7741 reference is bound, are destroyed at the end of the
7742 full-expression in which they are created.
7744 In that case, we store the converted expression into a new
7745 VAR_DECL in a new scope.
7747 However, we want to be careful not to create temporaries when
7748 they are not required. For example, given:
7750 struct B {};
7751 struct D : public B {};
7752 D f();
7753 const B& b = f();
7755 there is no need to copy the return value from "f"; we can just
7756 extend its lifetime. Similarly, given:
7758 struct S {};
7759 struct T { operator S(); };
7760 T t;
7761 const S& s = t;
7763 we can extend the lifetime of the return value of the conversion
7764 operator. */
7767 {
7768 tree var;
7769 tree base_conv_type;
7771 /* Skip over the REF_BIND. */
7773 /* If the next conversion is a BASE_CONV, skip that too -- but
7774 remember that the conversion was required. */
7776 {
7779 }
7780 else
7782 /* Perform the remainder of the conversion. */
7788 tf_warning_or_error);
7791 else
7792 {
7794 {
7795 tree init;
7797 /* Use its address to initialize the reference variable. */
7805 }
7806 else
7807 /* Take the address of EXPR. */
7809 /* If a BASE_CONV was required, perform it now. */
7811 expr = (perform_implicit_conversion
7813 tf_warning_or_error));
7815 }
7816 }
7817 else
7818 /* Perform the conversion. */
7821 /* Free all the conversions we allocated. */
7825 }
7827 /* Returns true iff TYPE is some variant of std::initializer_list. */
7829 bool
7831 {
7835 }
7837 /* Returns true iff DECL is a list constructor: i.e. a constructor which
7838 will accept an argument list of a single std::initializer_list<T>. */
7840 bool
7842 {
7844 tree arg;
7856 /* There are more non-defaulted parms. */
7860 }