| blob | f0350423e7ce8f0f2b104c6fbf79a681b87a8a28 |
1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
12 any later version.
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
46 /* The type of functions taking a tree, and some additional data, and
47 returning an int. */
50 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
51 instantiations have been deferred, either because their definitions
52 were not yet available, or because we were putting off doing the work.
53 The TREE_PURPOSE of each entry is either a DECL (for a function or
54 static data member), or a TYPE (for a class) indicating what we are
55 hoping to instantiate. The TREE_VALUE is not used. */
70 /* A map from local variable declarations in the body of the template
71 presently being instantiated to the corresponding instantiated
72 local variables. */
75 #define UNIFY_ALLOW_NONE 0
76 #define UNIFY_ALLOW_MORE_CV_QUAL 1
77 #define UNIFY_ALLOW_LESS_CV_QUAL 2
78 #define UNIFY_ALLOW_DERIVED 4
79 #define UNIFY_ALLOW_INTEGER 8
80 #define UNIFY_ALLOW_OUTER_LEVEL 16
81 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
82 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
83 #define UNIFY_ALLOW_MAX_CORRECTION 128
86 virtual, or a base class of a virtual
87 base. */
89 type with the desired type. */
171 /* Make the current scope suitable for access checking when we are
172 processing T. T can be FUNCTION_DECL for instantiated function
173 template, or VAR_DECL for static member variable (need by
174 instantiate_decl). */
176 static void
178 {
185 else
189 {
190 saved_access_scope = tree_cons
193 }
194 }
196 /* Restore the scope set up by push_access_scope. T is the node we
197 are processing. */
199 static void
201 {
203 {
206 }
210 else
212 }
214 /* Do any processing required when DECL (a member template
215 declaration) is finished. Returns the TEMPLATE_DECL corresponding
216 to DECL, unless it is a specialization, in which case the DECL
217 itself is returned. */
219 tree
221 {
228 {
229 tree type;
235 {
239 }
241 }
245 {
247 {
250 }
251 else
253 }
254 else
258 }
260 /* Returns the template nesting level of the indicated class TYPE.
262 For example, in:
263 template <class T>
264 struct A
265 {
266 template <class U>
267 struct B {};
268 };
270 A<T>::B<U> has depth two, while A<T> has depth one.
271 Both A<T>::B<int> and A<int>::B<U> have depth one, if
272 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
273 specializations.
275 This function is guaranteed to return 0 if passed NULL_TREE so
276 that, for example, `template_class_depth (current_class_type)' is
277 always safe. */
279 static int
281 {
288 {
290 {
293 && ((count_specializations
297 }
298 else
299 {
302 && ((count_specializations
306 }
307 }
310 }
312 /* Returns the template nesting level of the indicated class TYPE.
313 Like template_class_depth_real, but instantiations do not count in
314 the depth. */
316 int
318 {
320 }
322 /* Returns 1 if processing DECL as part of do_pending_inlines
323 needs us to push template parms. */
325 static int
327 {
333 }
335 /* Subroutine of maybe_begin_member_template_processing.
336 Push the template parms in PARMS, starting from LEVELS steps into the
337 chain, and ending at the beginning, since template parms are listed
338 innermost first. */
340 static void
342 {
350 current_template_parms
356 NULL);
358 {
363 {
370 {
371 /* Make a CONST_DECL as is done in process_template_parm.
372 It is ugly that we recreate this here; the original
373 version built in process_template_parm is no longer
374 available. */
382 }
387 }
388 }
389 }
391 /* Restore the template parameter context for a member template or
392 a friend template defined in a class definition. */
394 void
396 {
397 tree parms;
401 {
406 {
409 }
412 }
414 /* Remember how many levels of template parameters we pushed so that
415 we can pop them later. */
422 }
424 /* Undo the effects of begin_member_template_processing. */
426 void
428 {
438 {
442 }
443 }
445 /* Returns nonzero iff T is a member template function. We must be
446 careful as in
448 template <class T> class C { void f(); }
450 Here, f is a template function, and a member, but not a member
451 template. This function does not concern itself with the origin of
452 T, only its present state. So if we have
454 template <class T> class C { template <class U> void f(U); }
456 then neither C<int>::f<char> nor C<T>::f<double> is considered
457 to be a member template. But, `template <class U> void
458 C<int>::f(U)' is considered a member template. */
460 int
462 {
464 /* Anything that isn't a function or a template function is
465 certainly not a member template. */
468 /* A local class can't have member templates. */
473 /* If there are more levels of template parameters than
474 there are template classes surrounding the declaration,
475 then we have a member template. */
478 }
481 /* Returns nonzero iff T is a member template class. See
482 is_member_template for a description of what precisely constitutes
483 a member template. */
485 int
487 {
489 /* Anything that isn't a class template, is certainly not a member
490 template. */
494 /* Anything whose context isn't a class type is surely not a
495 member template. */
498 /* If there are more levels of template parameters than there are
499 template classes surrounding the declaration, then we have a
500 member template. */
503 }
504 #endif
506 /* Return a new template argument vector which contains all of ARGS,
507 but has as its innermost set of arguments the EXTRA_ARGS. */
509 static tree
511 {
512 tree new_args;
527 }
529 /* Like add_to_template_args, but only the outermost ARGS are added to
530 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
531 (EXTRA_ARGS) levels are added. This function is used to combine
532 the template arguments from a partial instantiation with the
533 template arguments used to attain the full instantiation from the
534 partial instantiation. */
536 static tree
538 {
539 tree new_args;
541 /* If there are more levels of EXTRA_ARGS than there are ARGS,
542 something very fishy is going on. */
546 /* If *all* the new arguments will be the EXTRA_ARGS, just return
547 them. */
551 /* For the moment, we make ARGS look like it contains fewer levels. */
556 /* Now, we restore ARGS to its full dimensions. */
560 }
562 /* Return the N levels of innermost template arguments from the ARGS. */
564 tree
566 {
567 tree new_args;
573 /* If N is 1, just return the innermost set of template arguments. */
577 /* If we're not removing anything, just return the arguments we were
578 given. */
584 /* Make a new set of arguments, not containing the outer arguments. */
591 }
593 /* We've got a template header coming up; push to a new level for storing
594 the parms. */
596 void
598 {
599 /* We use a non-tag-transparent scope here, which causes pushtag to
600 put tags in this scope, rather than in the enclosing class or
601 namespace scope. This is the right thing, since we want
602 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
603 global template class, push_template_decl handles putting the
604 TEMPLATE_DECL into top-level scope. For a nested template class,
605 e.g.:
607 template <class T> struct S1 {
608 template <class T> struct S2 {};
609 };
611 pushtag contains special code to call pushdecl_with_scope on the
612 TEMPLATE_DECL for S2. */
617 }
619 /* This routine is called when a specialization is declared. If it is
620 invalid to declare a specialization here, an error is reported. */
622 static void
624 {
627 /* [temp.expl.spec]
629 An explicit specialization shall be declared in the namespace of
630 which the template is a member, or, for member templates, in the
631 namespace of which the enclosing class or enclosing class
632 template is a member. An explicit specialization of a member
633 function, member class or static data member of a class template
634 shall be declared in the namespace of which the class template
635 is a member. */
638 scope);
640 /* [temp.expl.spec]
642 In an explicit specialization declaration for a member of a class
643 template or a member template that appears in namespace scope,
644 the member template and some of its enclosing class templates may
645 remain unspecialized, except that the declaration shall not
646 explicitly specialize a class member template if its enclosing
647 class templates are not explicitly specialized as well. */
650 }
652 /* We've just seen template <>. */
654 void
656 {
660 }
662 /* Called at then end of processing a declaration preceded by
663 template<>. */
665 void
667 {
670 }
672 /* Any template <>'s that we have seen thus far are not referring to a
673 function specialization. */
675 void
677 {
680 }
682 /* We've just seen a template header. If SPECIALIZATION is nonzero,
683 it was of the form template <>. */
685 static void
687 {
689 template_header_count++;
690 }
692 /* We're beginning an explicit instantiation. */
694 void
696 {
699 }
702 void
704 {
707 }
709 /* The TYPE is being declared. If it is a template type, that means it
710 is a partial specialization. Do appropriate error-checking. */
712 void
714 {
715 /* TYPE maybe an ERROR_MARK_NODE. */
719 {
720 /* This is for ordinary explicit specialization and partial
721 specialization of a template class such as:
723 template <> class C<int>;
725 or:
727 template <class T> class C<T*>;
729 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
733 {
737 else
738 {
742 }
746 }
749 }
755 {
756 /* This is for an explicit specialization of member class
757 template according to [temp.expl.spec/18]:
759 template <> template <class U> class C<int>::D;
761 The context `C<int>' must be an implicit instantiation.
762 Otherwise this is just a member class template declared
763 earlier like:
765 template <> class C<int> { template <class U> class D; };
766 template <> template <class U> class C<int>::D;
768 In the first case, `C<int>::D' is a specialization of `C<T>::D'
769 while in the second case, `C<int>::D' is a primary template
770 and `C<T>::D' may not exist. */
774 {
775 tree t;
779 {
783 }
785 /* Check for invalid specialization after instantiation:
787 template <> template <> class C<int>::D<int>;
788 template <> template <class U> class C<int>::D; */
798 /* Mark TYPE as a specialization. And as a result, we only
799 have one level of template argument for the innermost
800 class template. */
804 }
805 }
808 }
810 /* Retrieve the specialization (in the sense of [temp.spec] - a
811 specialization is either an instantiation or an explicit
812 specialization) of TMPL for the given template ARGS. If there is
813 no such specialization, return NULL_TREE. The ARGS are a vector of
814 arguments, or a vector of vectors of arguments, in the case of
815 templates with more than one level of parameters. */
817 static tree
819 {
820 tree s;
824 /* There should be as many levels of arguments as there are
825 levels of parameters. */
837 }
839 /* Like retrieve_specialization, but for local declarations. */
841 static tree
843 {
847 }
849 /* Returns nonzero iff DECL is a specialization of TMPL. */
851 int
853 {
854 tree t;
857 {
863 }
864 else
865 {
874 }
877 }
879 /* Returns nonzero iff DECL is a specialization of friend declaration
880 FRIEND according to [temp.friend]. */
882 bool
884 {
890 /* For [temp.friend/6] when FRIEND is an ordinary member function
891 of a template class, we want to check if DECL is a specialization
892 if this. */
896 {
899 }
901 /* There is nothing to do if this is not a template friend. */
908 /* [temp.friend/6]
909 A member of a class template may be declared to be a friend of a
910 non-template class. In this case, the corresponding member of
911 every specialization of the class template is a friend of the
912 class granting friendship.
914 For example, given a template friend declaration
916 template <class T> friend void A<T>::f();
918 the member function below is considered a friend
920 template <> struct A<int> {
921 void f();
922 };
924 For this type of template friend, TEMPLATE_DEPTH below will be
925 nonzero. To determine if DECL is a friend of FRIEND, we first
926 check if the enclosing class is a specialization of another. */
933 {
934 /* Next, we check the members themselves. In order to handle
935 a few tricky cases like
937 template <class T> friend void A<T>::g(T t);
938 template <class T> template <T t> friend void A<T>::h();
940 we need to figure out what ARGS is (corresponding to `T' in above
941 examples) from DECL for later processing. */
947 {
949 {
952 else
954 current_depth++;
955 }
957 }
960 {
962 tree friend_type;
963 tree decl_type;
964 tree friend_args_type;
965 tree decl_args_type;
967 /* Make sure that both DECL and FRIEND are templates or
968 non-templates. */
974 {
975 /* If both are templates, check template parameter list. */
976 tree friend_parms
981 friend_parms))
985 }
986 else
994 /* Check if return types match. */
998 /* Check if function parameter types match, ignoring the
999 `this' parameter. */
1008 }
1009 }
1011 }
1013 /* Register the specialization SPEC as a specialization of TMPL with
1014 the indicated ARGS. Returns SPEC, or an equivalent prior
1015 declaration, if available. */
1017 static tree
1019 {
1020 tree s;
1026 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1027 register it; we want the corresponding TEMPLATE_DECL instead.
1028 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1029 the more obvious `uses_template_parms (spec)' to avoid problems
1030 with default function arguments. In particular, given
1031 something like this:
1033 template <class T> void f(T t1, T t = T())
1035 the default argument expression is not substituted for in an
1036 instantiation unless and until it is actually needed. */
1039 /* There should be as many levels of arguments as there are
1040 levels of parameters. */
1048 {
1051 /* We can sometimes try to re-register a specialization that we've
1052 already got. In particular, regenerate_decl_from_template
1053 calls duplicate_decls which will update the specialization
1054 list. But, we'll still get called again here anyhow. It's
1055 more convenient to simply allow this than to try to prevent it. */
1059 {
1061 {
1063 {
1066 {
1068 fn);
1070 }
1071 else
1072 {
1073 /* This situation should occur only if the first
1074 specialization is an implicit instantiation,
1075 the second is an explicit specialization, and
1076 the implicit instantiation has not yet been
1077 used. That situation can occur if we have
1078 implicitly instantiated a member function and
1079 then specialized it later.
1081 We can also wind up here if a friend
1082 declaration that looked like an instantiation
1083 turns out to be a specialization:
1085 template <class T> void foo(T);
1086 class S { friend void foo<>(int) };
1087 template <> void foo(int);
1089 We transform the existing DECL in place so that
1090 any pointers to it become pointers to the
1091 updated declaration.
1093 If there was a definition for the template, but
1094 not for the specialization, we want this to
1095 look as if there were no definition, and vice
1096 versa. */
1101 }
1102 }
1104 {
1106 /* Dup decl failed, but this is a new
1107 definition. Set the line number so any errors
1108 match this new definition. */
1112 }
1113 }
1114 }
1115 }
1121 }
1123 /* Unregister the specialization SPEC as a specialization of TMPL.
1124 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1125 if the SPEC was listed as a specialization of TMPL. */
1127 bool
1129 {
1136 {
1139 else
1142 }
1145 }
1147 /* Compare an entry in the local specializations hash table P1 (which
1148 is really a pointer to a TREE_LIST) with P2 (which is really a
1149 DECL). */
1151 static int
1153 {
1155 }
1157 /* Hash P1, an entry in the local specializations table. */
1159 static hashval_t
1161 {
1163 }
1165 /* Like register_specialization, but for local declarations. We are
1166 registering SPEC, an instantiation of TMPL. */
1168 static void
1170 {
1176 }
1178 /* Print the list of candidate FNS in an error message. */
1180 void
1182 {
1183 tree fn;
1188 {
1189 tree f;
1194 }
1195 }
1197 /* Returns the template (one of the functions given by TEMPLATE_ID)
1198 which can be specialized to match the indicated DECL with the
1199 explicit template args given in TEMPLATE_ID. The DECL may be
1200 NULL_TREE if none is available. In that case, the functions in
1201 TEMPLATE_ID are non-members.
1203 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1204 specialization of a member template.
1206 The template args (those explicitly specified and those deduced)
1207 are output in a newly created vector *TARGS_OUT.
1209 If it is impossible to determine the result, an error message is
1210 issued. The error_mark_node is returned to indicate failure. */
1212 static tree
1214 tree decl,
1217 {
1218 tree fns;
1219 tree targs;
1220 tree explicit_targs;
1235 /* Check for baselinks. */
1240 {
1243 }
1246 {
1250 {
1251 tree decl_arg_types;
1253 /* DECL might be a specialization of FN. */
1255 /* Adjust the type of DECL in case FN is a static member. */
1261 /* Check that the number of function parameters matches.
1262 For example,
1263 template <class T> void f(int i = 0);
1264 template <> void f<int>();
1265 The specialization f<int> is invalid but is not caught
1266 by get_bindings below. */
1272 /* See whether this function might be a specialization of this
1273 template. */
1277 /* We cannot deduce template arguments that when used to
1278 specialize TMPL will produce DECL. */
1281 /* Save this template, and the arguments deduced. */
1283 }
1285 /* FN is an ordinary member function, and we need a
1286 specialization of a member template. */
1287 ;
1289 /* We can get IDENTIFIER_NODEs here in certain erroneous
1290 cases. */
1291 ;
1293 /* This is just an ordinary non-member function. Nothing can
1294 be a specialization of that. */
1295 ;
1297 /* Cannot specialize functions that are created implicitly. */
1298 ;
1299 else
1300 {
1301 tree decl_arg_types;
1303 /* This is an ordinary member function. However, since
1304 we're here, we can assume it's enclosing class is a
1305 template class. For example,
1307 template <typename T> struct S { void f(); };
1308 template <> void S<int>::f() {}
1310 Here, S<int>::f is a non-template, but S<int> is a
1311 template class. If FN has the same type as DECL, we
1312 might be in business. */
1315 /* Its enclosing class is an explicit specialization
1316 of a template class. This is not a candidate. */
1321 /* The return types differ. */
1324 /* Adjust the type of DECL in case FN is a static member. */
1331 decl_arg_types))
1332 /* They match! */
1334 }
1335 }
1338 {
1339 /* We have:
1341 [temp.expl.spec]
1343 It is possible for a specialization with a given function
1344 signature to be instantiated from more than one function
1345 template. In such cases, explicit specification of the
1346 template arguments must be used to uniquely identify the
1347 function template specialization being specialized.
1349 Note that here, there's no suggestion that we're supposed to
1350 determine which of the candidate templates is most
1351 specialized. However, we, also have:
1353 [temp.func.order]
1355 Partial ordering of overloaded function template
1356 declarations is used in the following contexts to select
1357 the function template to which a function template
1358 specialization refers:
1360 -- when an explicit specialization refers to a function
1361 template.
1363 So, we do use the partial ordering rules, at least for now.
1364 This extension can only serve to make invalid programs valid,
1365 so it's safe. And, there is strong anecdotal evidence that
1366 the committee intended the partial ordering rules to apply;
1367 the EDG front-end has that behavior, and John Spicer claims
1368 that the committee simply forgot to delete the wording in
1369 [temp.expl.spec]. */
1372 {
1375 }
1376 }
1379 {
1383 }
1387 {
1393 }
1395 /* We have one, and exactly one, match. */
1397 {
1398 /* It was a specialization of an ordinary member function in a
1399 template class. */
1402 }
1404 /* It was a specialization of a template. */
1407 {
1412 }
1413 else
1416 }
1418 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1419 but with the default argument values filled in from those in the
1420 TMPL_TYPES. */
1422 static tree
1424 tree tmpl_types)
1425 {
1426 tree new_spec_types;
1434 /* Substitute into the rest of the list. */
1435 new_spec_types =
1439 /* Add the default argument for this parameter. */
1442 new_spec_types);
1443 }
1445 /* DECL is an explicit specialization. Replicate default arguments
1446 from the template it specializes. (That way, code like:
1448 template <class T> void f(T = 3);
1449 template <> void f(double);
1450 void g () { f (); }
1452 works, as required.) An alternative approach would be to look up
1453 the correct default arguments at the call-site, but this approach
1454 is consistent with how implicit instantiations are handled. */
1456 static void
1458 {
1459 tree tmpl;
1460 tree spec_types;
1461 tree tmpl_types;
1462 tree new_spec_types;
1463 tree old_type;
1464 tree new_type;
1465 tree t;
1470 /* See if there's anything we need to do. */
1483 {
1484 /* Remove the this pointer, but remember the object's type for
1485 CV quals. */
1491 {
1492 /* DECL may contain more parameters than TMPL due to the extra
1493 in-charge parameter in constructors and destructors. */
1496 }
1498 {
1501 }
1502 }
1504 /* Compute the merged default arguments. */
1505 new_spec_types =
1508 /* Compute the new FUNCTION_TYPE. */
1510 {
1514 new_spec_types);
1517 /* Put the in-charge parameter back. */
1520 new_spec_types);
1524 new_spec_types);
1525 }
1526 else
1528 new_spec_types);
1534 }
1536 /* Check to see if the function just declared, as indicated in
1537 DECLARATOR, and in DECL, is a specialization of a function
1538 template. We may also discover that the declaration is an explicit
1539 instantiation at this point.
1541 Returns DECL, or an equivalent declaration that should be used
1542 instead if all goes well. Issues an error message if something is
1543 amiss. Returns error_mark_node if the error is not easily
1544 recoverable.
1546 FLAGS is a bitmask consisting of the following flags:
1548 2: The function has a definition.
1549 4: The function is a friend.
1551 The TEMPLATE_COUNT is the number of references to qualifying
1552 template classes that appeared in the name of the function. For
1553 example, in
1555 template <class T> struct S { void f(); };
1556 void S<int>::f();
1558 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1559 classes are not counted in the TEMPLATE_COUNT, so that in
1561 template <class T> struct S {};
1562 template <> struct S<int> { void f(); }
1563 template <> void S<int>::f();
1565 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1566 invalid; there should be no template <>.)
1568 If the function is a specialization, it is marked as such via
1569 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1570 is set up correctly, and it is added to the list of specializations
1571 for that template. */
1573 tree
1575 tree decl,
1578 {
1586 tmpl_spec_kind tsk;
1591 {
1594 {
1597 }
1599 {
1601 /* This could be something like:
1603 template <class T> void f(T);
1604 class S { friend void f<>(int); } */
1606 else
1607 {
1608 /* This case handles bogus declarations like template <>
1609 template <class T> void f<int>(); */
1612 declarator);
1614 }
1615 }
1619 /* The error has already been reported in
1620 check_specialization_scope. */
1626 /* Fall through. */
1637 decl);
1640 /* Fall through. */
1645 else
1651 {
1653 decl);
1655 }
1660 {
1661 /* For backwards compatibility, we accept:
1663 template <class T> struct S { void f(); };
1664 void S<int>::f() {} // Missing template <>
1666 That used to be valid C++. */
1668 pedwarn
1672 }
1677 {
1678 /* This case handles bogus declarations like template <>
1679 template <class T> void f<int>(); */
1683 declarator);
1684 else
1686 declarator);
1688 }
1691 /* This is a specialization of a member template, without
1692 specialization the containing class. Something like:
1694 template <class T> struct S {
1695 template <class U> void f (U);
1696 };
1697 template <> template <class U> void S<int>::f(U) {}
1699 That's a specialization -- but of the entire template. */
1705 }
1708 {
1712 {
1713 pedwarn
1716 }
1719 }
1722 {
1726 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1728 {
1729 tree fns;
1734 else
1735 {
1736 /* If there is no class context, the explicit instantiation
1737 must be at namespace scope. */
1740 /* Find the namespace binding, using the declaration
1741 context. */
1743 }
1746 }
1752 {
1754 /* A specialization in class scope. This is invalid,
1755 but the error will already have been flagged by
1756 check_specialization_scope. */
1758 else
1759 {
1760 /* It's not valid to write an explicit instantiation in
1761 class scope, e.g.:
1763 class C { template void f(); }
1765 This case is caught by the parser. However, on
1766 something like:
1768 template class C { void f(); };
1770 (which is invalid) we can get here. The error will be
1771 issued later. */
1772 ;
1773 }
1776 }
1779 IDENTIFIER_NODE))
1780 {
1781 /* Find the list of functions in ctype that have the same
1782 name as the declared function. */
1788 {
1793 {
1794 /* From [temp.expl.spec]:
1796 If such an explicit specialization for the member
1797 of a class template names an implicitly-declared
1798 special member function (clause _special_), the
1799 program is ill-formed.
1801 Similar language is found in [temp.explicit]. */
1804 }
1807 }
1810 {
1814 }
1815 else
1816 {
1817 tree methods;
1819 /* For a type-conversion operator, we cannot do a
1820 name-based lookup. We might be looking for `operator
1821 int' which will be a specialization of `operator T'.
1822 So, we find *all* the conversion operators, and then
1823 select from them. */
1830 {
1834 /* There are no more conversion functions. */
1837 /* Glue all these conversion functions together
1838 with those we already have. */
1841 }
1842 }
1845 {
1849 }
1850 else
1852 }
1854 /* Figure out what exactly is being specialized at this point.
1855 Note that for an explicit instantiation, even one for a
1856 member function, we cannot tell apriori whether the
1857 instantiation is for a member template, or just a member
1858 function of a template class. Even if a member template is
1859 being instantiated, the member template arguments may be
1860 elided if they can be deduced from the rest of the
1861 declaration. */
1864 member_specialization);
1867 /* We couldn't figure out what this declaration was
1868 specializing. */
1870 else
1871 {
1875 {
1876 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1877 is done by do_decl_instantiation later. */
1883 {
1884 /* If TMPL is not the most general template (for
1885 example, if TMPL is a friend template that is
1886 injected into namespace scope), then there will
1887 be too many levels of TARGS. Remove some of them
1888 here. */
1890 tree new_targs;
1897 }
1900 }
1902 /* If we thought that the DECL was a member function, but it
1903 turns out to be specializing a static member function,
1904 make DECL a static member function as well. We also have
1905 to adjust last_function_parms to avoid confusing
1906 start_function later. */
1909 {
1912 }
1914 /* If this is a specialization of a member template of a
1915 template class. In we want to return the TEMPLATE_DECL,
1916 not the specialization of it. */
1918 {
1922 {
1926 }
1928 }
1930 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1933 /* Inherit default function arguments from the template
1934 DECL is specializing. */
1937 /* This specialization has the same protection as the
1938 template it specializes. */
1943 /* This is not really a declaration of a specialization.
1944 It's just the name of an instantiation. But, it's not
1945 a request for an instantiation, either. */
1948 /* This is indeed a specialization. In case of constructors
1949 and destructors, we need in-charge and not-in-charge
1950 versions in V3 ABI. */
1953 /* Register this specialization so that we can find it
1954 again. */
1956 }
1957 }
1960 }
1962 /* TYPE is being declared. Verify that the use of template headers
1963 and such is reasonable. Issue error messages if not. */
1965 void
1967 {
1969 {
1970 /* We are in the scope of some `template <...>' header. */
1972 int context_depth
1977 /* This is OK; the template headers are for the context. We
1978 are actually too lenient here; like
1979 check_explicit_specialization we should consider the number
1980 of template types included in the actual declaration. For
1981 example,
1983 template <class T> struct S {
1984 template <class U> template <class V>
1985 struct I {};
1986 };
1988 is invalid, but:
1990 template <class T> struct S {
1991 template <class U> struct I;
1992 };
1994 template <class T> template <class U.
1995 struct S<T>::I {};
1997 is not. */
1998 ;
2000 /* There are two many template parameter lists. */
2002 }
2003 }
2005 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2006 parameters. These are represented in the same format used for
2007 DECL_TEMPLATE_PARMS. */
2010 {
2011 tree p1;
2012 tree p2;
2020 {
2032 {
2043 }
2044 }
2047 /* One set of parameters has more parameters lists than the
2048 other. */
2052 }
2054 /* Complain if DECL shadows a template parameter.
2056 [temp.local]: A template-parameter shall not be redeclared within its
2057 scope (including nested scopes). */
2059 void
2061 {
2062 tree olddecl;
2064 /* If we're not in a template, we can't possibly shadow a template
2065 parameter. */
2069 /* Figure out what we're shadowing. */
2074 /* If there's no previous binding for this name, we're not shadowing
2075 anything, let alone a template parameter. */
2079 /* If we're not shadowing a template parameter, we're done. Note
2080 that OLDDECL might be an OVERLOAD (or perhaps even an
2081 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2082 node. */
2086 /* We check for decl != olddecl to avoid bogus errors for using a
2087 name inside a class. We check TPFI to avoid duplicate errors for
2088 inline member templates. */
2095 }
2097 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2098 ORIG_LEVEL, DECL, and TYPE. */
2100 static tree
2104 tree decl,
2105 tree type)
2106 {
2117 }
2119 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2120 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2121 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2122 new one is created. */
2124 static tree
2126 {
2130 {
2146 /* Template template parameters need this. */
2149 }
2152 }
2154 /* Process information from new template parameter NEXT and append it to the
2155 LIST being built. */
2157 tree
2159 {
2160 tree parm;
2162 tree defval;
2172 {
2177 else
2180 }
2181 else
2185 {
2187 /* is a const-param */
2192 /* [temp.param]
2194 The top-level cv-qualifiers on the template-parameter are
2195 ignored when determining its type. */
2198 /* A template parameter is not modifiable. */
2206 processing_template_decl,
2208 }
2209 else
2210 {
2211 tree t;
2215 {
2217 /* This is for distinguishing between real templates and template
2218 template parameters */
2222 }
2223 else
2224 {
2226 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2228 }
2235 processing_template_decl,
2237 }
2243 }
2245 /* The end of a template parameter list has been reached. Process the
2246 tree list into a parameter vector, converting each parameter into a more
2247 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2248 as PARM_DECLs. */
2250 tree
2252 {
2257 current_template_parms
2262 {
2266 }
2271 }
2273 /* end_template_decl is called after a template declaration is seen. */
2275 void
2277 {
2283 /* This matches the pushlevel in begin_template_parm_list. */
2288 }
2290 /* Given a template argument vector containing the template PARMS.
2291 The innermost PARMS are given first. */
2293 tree
2295 {
2296 tree header;
2301 /* If there is only one level of template parameters, we do not
2302 create a TREE_VEC of TREE_VECs. Instead, we return a single
2303 TREE_VEC containing the arguments. */
2308 {
2314 {
2317 /* T will be a list if we are called from within a
2318 begin/end_template_parm_list pair, but a vector directly
2319 if within a begin/end_member_template_processing pair. */
2321 {
2327 else
2330 }
2331 }
2335 else
2337 }
2340 }
2342 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2343 template PARMS. Used by push_template_decl below. */
2345 static tree
2347 {
2352 {
2361 }
2364 }
2366 struct template_parm_data
2367 {
2368 /* The level of the template parameters we are currently
2369 processing. */
2372 /* The index of the specialization argument we are currently
2373 processing. */
2376 /* An array whose size is the number of template parameters. The
2377 elements are nonzero if the parameter has been used in any one
2378 of the arguments processed so far. */
2381 /* An array whose size is the number of template arguments. The
2382 elements are nonzero if the argument makes use of template
2383 parameters of this level. */
2385 };
2387 /* Subroutine of push_template_decl used to see if each template
2388 parameter in a partial specialization is used in the explicit
2389 argument list. If T is of the LEVEL given in DATA (which is
2390 treated as a template_parm_data*), then DATA->PARMS is marked
2391 appropriately. */
2393 static int
2395 {
2401 {
2404 }
2405 else
2406 {
2409 }
2412 {
2415 }
2417 /* Return zero so that for_each_template_parm will continue the
2418 traversal of the tree; we want to mark *every* template parm. */
2420 }
2422 /* Process the partial specialization DECL. */
2424 static tree
2426 {
2440 /* We check that each of the template parameters given in the
2441 partial specialization is used in the argument list to the
2442 specialization. For example:
2444 template <class T> struct S;
2445 template <class T> struct S<T*>;
2447 The second declaration is OK because `T*' uses the template
2448 parameter T, whereas
2450 template <class T> struct S<int>;
2452 is no good. Even trickier is:
2454 template <class T>
2455 struct S1
2456 {
2457 template <class U>
2458 struct S2;
2459 template <class U>
2460 struct S2<T>;
2461 };
2463 The S2<T> declaration is actually invalid; it is a
2464 full-specialization. Of course,
2466 template <class U>
2467 struct S2<T (*)(U)>;
2469 or some such would have been OK. */
2477 {
2482 NULL);
2483 }
2486 {
2487 /* One of the template parms was not used in the
2488 specialization. */
2490 {
2493 }
2497 }
2499 /* [temp.class.spec]
2501 The argument list of the specialization shall not be identical to
2502 the implicit argument list of the primary template. */
2509 /* [temp.class.spec]
2511 A partially specialized non-type argument expression shall not
2512 involve template parameters of the partial specialization except
2513 when the argument expression is a simple identifier.
2515 The type of a template parameter corresponding to a specialized
2516 non-type argument shall not be dependent on a parameter of the
2517 specialization. */
2521 {
2526 /* This next line is the `argument expression is not just a
2527 simple identifier' condition and also the `specialized
2528 non-type argument' bit. */
2530 {
2533 else
2534 {
2535 /* Look at the corresponding template parameter,
2536 marking which template parameters its type depends
2537 upon. */
2538 tree type =
2540 i)));
2543 {
2544 /* We haven't yet initialized TPD2. Do so now. */
2545 tpd2.arg_uses_template_parms
2547 /* The number of parameters here is the number in the
2548 main template, which, as checked in the assertion
2549 above, is NARGS. */
2553 }
2555 /* Mark the template parameters. But this time, we're
2556 looking for the template parameters of the main
2557 template, not in the specialization. */
2564 NULL);
2567 {
2568 /* The type depended on some template parameters.
2569 If they are fully specialized in the
2570 specialization, that's OK. */
2575 {
2577 type,
2578 arg);
2580 }
2581 }
2582 }
2583 }
2584 }
2587 /* We've already got this specialization. */
2595 }
2597 /* Check that a template declaration's use of default arguments is not
2598 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2599 nonzero if DECL is the thing declared by a primary template.
2600 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2602 static void
2604 {
2607 tree parm_level;
2609 /* [temp.param]
2611 A default template-argument shall not be specified in a
2612 function template declaration or a function template definition, nor
2613 in the template-parameter-list of the definition of a member of a
2614 class template. */
2617 /* You can't have a function template declaration in a local
2618 scope, nor you can you define a member of a class template in a
2619 local scope. */
2625 /* If this is either a friend defined in the scope of the class
2626 or a member function. */
2632 /* And, if it was a member function, it really was defined in
2633 the scope of the class. */
2636 /* We already checked these parameters when the template was
2637 declared, so there's no need to do it again now. This function
2638 was defined in class scope, but we're processing it's body now
2639 that the class is complete. */
2642 /* [temp.param]
2644 If a template-parameter has a default template-argument, all
2645 subsequent template-parameters shall have a default
2646 template-argument supplied. */
2648 {
2655 {
2660 {
2662 /* For better subsequent error-recovery, we indicate that
2663 there should have been a default argument. */
2665 }
2666 }
2667 }
2670 /* For an ordinary class template, default template arguments are
2671 allowed at the innermost level, e.g.:
2672 template <class T = int>
2673 struct S {};
2674 but, in a partial specialization, they're not allowed even
2675 there, as we have in [temp.class.spec]:
2677 The template parameter list of a specialization shall not
2678 contain default template argument values.
2680 So, for a partial specialization, or for a function template,
2681 we look at all of them. */
2682 ;
2683 else
2684 /* But, for a primary class template that is not a partial
2685 specialization we look at all template parameters except the
2686 innermost ones. */
2689 /* Figure out what error message to issue. */
2694 else
2698 /* If we're inside a class definition, there's no need to
2699 examine the parameters to the class itself. On the one
2700 hand, they will be checked when the class is defined, and,
2701 on the other, default arguments are valid in things like:
2702 template <class T = double>
2703 struct S { template <class U> void f(U); };
2704 Here the default argument for `S' has no bearing on the
2705 declaration of `f'. */
2707 else
2708 /* Check everything. */
2714 {
2722 {
2724 {
2727 }
2729 /* Clear out the default argument so that we are not
2730 confused later. */
2732 }
2734 /* At this point, if we're still interested in issuing messages,
2735 they must apply to classes surrounding the object declared. */
2738 }
2739 }
2741 /* Worker for push_template_decl_real, called via
2742 for_each_template_parm. DATA is really an int, indicating the
2743 level of the parameters we are interested in. If T is a template
2744 parameter of that level, return nonzero. */
2746 static int
2748 {
2754 else
2757 }
2759 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2760 parameters given by current_template_args, or reuses a
2761 previously existing one, if appropriate. Returns the DECL, or an
2762 equivalent one, if it is replaced via a call to duplicate_decls.
2764 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2766 tree
2768 {
2769 tree tmpl;
2770 tree args;
2771 tree info;
2772 tree ctx;
2777 /* See if this is a partial specialization. */
2785 /* For a friend, we want the context of the friend function, not
2786 the type of which it is a friend. */
2790 /* In the case of a virtual function, we want the class in which
2791 it is defined. */
2793 else
2794 /* Otherwise, if we're currently defining some class, the DECL
2795 is assumed to be a member of the class. */
2804 /* See if this is a primary template. */
2808 {
2816 {
2817 /* [temp.mem]
2819 A destructor shall not be a member template. */
2822 }
2828 else
2829 {
2832 }
2833 }
2835 /* Check to see that the rules regarding the use of default
2836 arguments are not being violated. */
2849 {
2854 /* If DECL is a TYPE_DECL for a class-template, then there won't
2855 be DECL_LANG_SPECIFIC. The information equivalent to
2856 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2860 {
2861 /* Since a template declaration already existed for this
2862 class-type, we must be redeclaring it here. Make sure
2863 that the redeclaration is valid. */
2865 current_template_parms);
2866 /* We don't need to create a new TEMPLATE_DECL; just use the
2867 one we already had. */
2869 }
2870 else
2871 {
2877 {
2878 /* A specialization of a member template of a template
2879 class. */
2883 }
2884 }
2885 }
2886 else
2887 {
2892 {
2898 else
2899 {
2902 }
2903 }
2905 {
2908 }
2909 else
2916 {
2917 tree new_tmpl;
2919 /* The declaration is a specialization of a member
2920 template, declared outside the class. Therefore, the
2921 innermost template arguments will be NULL, so we
2922 replace them with the arguments determined by the
2923 earlier call to check_explicit_specialization. */
2926 new_tmpl
2937 args);
2939 }
2941 /* Make sure the template headers we got make sense. */
2946 {
2949 }
2950 else
2952 {
2957 {
2961 else
2965 }
2967 /* Perhaps we should also check that the parms are used in the
2968 appropriate qualifying scopes in the declarator? */
2972 else
2974 }
2975 }
2980 /* Push template declarations for global functions and types. Note
2981 that we do not try to push a global template friend declared in a
2982 template class; such a thing may well depend on the template
2983 parameters of the class. */
2989 {
2992 {
2995 /* It is a conversion operator. See if the type converted to
2996 depends on innermost template operands. */
2999 depth))
3001 }
3002 }
3007 {
3011 /* Don't change the name if we've already set it up. */
3014 }
3019 }
3021 tree
3023 {
3025 }
3027 /* Called when a class template TYPE is redeclared with the indicated
3028 template PARMS, e.g.:
3030 template <class T> struct S;
3031 template <class T> struct S {}; */
3033 void
3035 {
3036 tree tmpl;
3037 tree tmpl_parms;
3041 {
3044 }
3048 /* The type is nested in some template class. Nothing to worry
3049 about here; there are no new template parameters for the nested
3050 type. */
3057 {
3064 }
3067 {
3074 {
3078 }
3081 {
3082 /* We have in [temp.param]:
3084 A template-parameter may not be given default arguments
3085 by two different declarations in the same scope. */
3089 }
3092 /* Update the previous template parameters (which are the ones
3093 that will really count) with the new default value. */
3096 /* Update the new parameters, too; they'll be used as the
3097 parameters for any members. */
3099 }
3100 }
3102 /* Attempt to convert the non-type template parameter EXPR to the
3103 indicated TYPE. If the conversion is successful, return the
3104 converted value. If the conversion is unsuccessful, return
3105 NULL_TREE if we issued an error message, or error_mark_node if we
3106 did not. We issue error messages for out-and-out bad template
3107 parameters, but not simply because the conversion failed, since we
3108 might be just trying to do argument deduction. By the time this
3109 function is called, neither TYPE nor EXPR may make use of template
3110 parameters. */
3112 static tree
3114 {
3117 /* A template-argument for a non-type, non-template
3118 template-parameter shall be one of:
3120 --an integral constant-expression of integral or enumeration
3121 type; or
3123 --the name of a non-type template-parameter; or
3125 --the name of an object or function with external linkage,
3126 including function templates and function template-ids but
3127 excluding non-static class members, expressed as id-expression;
3128 or
3130 --the address of an object or function with external linkage,
3131 including function templates and function template-ids but
3132 excluding non-static class members, expressed as & id-expression
3133 where the & is optional if the name refers to a function or
3134 array; or
3136 --a pointer to member expressed as described in _expr.unary.op_. */
3138 /* An integral constant-expression can include const variables or
3139 enumerators. Simplify things by folding them to their values,
3140 unless we're about to bind the declaration to a reference
3141 parameter. */
3147 /* OK for now. We'll check that it has external linkage later.
3148 Check this first since if expr_type is the unknown_type_node
3149 we would otherwise complain below. */
3150 ;
3152 {
3155 }
3159 /* If expr is the address of an overloaded function, we
3160 will get the unknown_type_node at this point. */
3162 {
3163 tree referent;
3171 else
3172 {
3174 {
3175 bad_argument:
3178 {
3181 else
3183 }
3188 }
3192 }
3195 {
3196 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3197 referent);
3199 }
3205 /* We'll check that it has external linkage later. */
3206 ;
3210 {
3213 }
3214 }
3216 {
3218 {
3219 non_constant:
3221 expr);
3223 }
3224 }
3225 else
3226 {
3232 else
3236 }
3239 {
3243 /* For a non-type template-parameter of integral or enumeration
3244 type, integral promotions (_conv.prom_) and integral
3245 conversions (_conv.integral_) are applied. */
3249 /* It's safe to call digest_init in this case; we know we're
3250 just converting one integral constant expression to another. */
3254 /* Curiously, some TREE_CONSTANT integral expressions do not
3255 simplify to integer constants. For example, `3 % 0',
3256 remains a TRUNC_MOD_EXPR. */
3262 {
3263 tree e;
3265 /* For a non-type template-parameter of type pointer to data
3266 member, qualification conversions (_conv.qual_) are
3267 applied. */
3270 /* The call to perform_qualification_conversions will
3271 insert a NOP_EXPR over EXPR to do express conversion,
3272 if necessary. But, that will confuse us if we use
3273 this (converted) template parameter to instantiate
3274 another template; then the thing will not look like a
3275 valid template argument. So, just make a new
3276 constant, of the appropriate type. */
3279 }
3282 {
3286 {
3287 /* For a non-type template-parameter of type pointer to
3288 function, only the function-to-pointer conversion
3289 (_conv.func_) is applied. If the template-argument
3290 represents a set of overloaded functions (or a pointer to
3291 such), the matching function is selected from the set
3292 (_over.over_). */
3293 tree fns;
3294 tree fn;
3298 else
3307 {
3310 else
3312 }
3319 }
3320 else
3321 {
3322 /* For a non-type template-parameter of type pointer to
3323 object, qualification conversions (_conv.qual_) and the
3324 array-to-pointer conversion (_conv.array_) are applied.
3325 [Note: In particular, neither the null pointer conversion
3326 (_conv.ptr_) nor the derived-to-base conversion
3327 (_conv.ptr_) are applied. Although 0 is a valid
3328 template-argument for a non-type template-parameter of
3329 integral type, it is not a valid template-argument for a
3330 non-type template-parameter of pointer type.]
3332 The call to decay_conversion performs the
3333 array-to-pointer conversion, if appropriate. */
3338 else
3340 }
3341 }
3345 {
3348 /* If this expression already has reference type, get the
3349 underlying object. */
3351 {
3358 }
3361 {
3362 /* For a non-type template-parameter of type reference to
3363 function, no conversions apply. If the
3364 template-argument represents a set of overloaded
3365 functions, the matching function is selected from the
3366 set (_over.over_). */
3367 tree fn;
3375 {
3377 /* Don't issue an error here; we might get a different
3378 function if the overloading had worked out
3379 differently. */
3381 else
3383 }
3390 }
3391 else
3392 {
3393 /* For a non-type template-parameter of type reference to
3394 object, no conversions apply. The type referred to by the
3395 reference may be more cv-qualified than the (otherwise
3396 identical) type of the template-argument. The
3397 template-parameter is bound directly to the
3398 template-argument, which must be an lvalue. */
3402 expr_type)
3405 }
3409 }
3413 {
3416 /* For a non-type template-parameter of type pointer to member
3417 function, no conversions apply. If the template-argument
3418 represents a set of overloaded member functions, the
3419 matching member function is selected from the set
3420 (_over.over_). */
3427 {
3428 /* A ptr-to-member constant. */
3431 else
3433 }
3447 }
3451 /* All non-type parameters must have one of these types. */
3454 }
3457 }
3459 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3460 template template parameters. Both PARM_PARMS and ARG_PARMS are
3461 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3462 or PARM_DECL.
3464 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3465 the case, then extra parameters must have default arguments.
3467 Consider the example:
3468 template <class T, class Allocator = allocator> class vector;
3469 template<template <class U> class TT> class C;
3471 C<vector> is a valid instantiation. PARM_PARMS for the above code
3472 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3473 T and Allocator) and OUTER_ARGS contains the argument that is used to
3474 substitute the TT parameter. */
3476 static int
3478 tree arg_parms,
3479 tsubst_flags_t complain,
3480 tree in_decl,
3481 tree outer_args)
3482 {
3492 /* The rule here is opposite of coerce_template_parms. */
3499 {
3511 {
3516 /* We encounter instantiations of templates like
3517 template <template <template <class> class> class TT>
3518 class C; */
3519 {
3526 }
3530 /* The tsubst call is used to handle cases such as
3531 template <class T, template <T> class TT> class D;
3532 i.e. the parameter list of TT depends on earlier parameters. */
3541 }
3542 }
3544 }
3546 /* Convert the indicated template ARG as necessary to match the
3547 indicated template PARM. Returns the converted ARG, or
3548 error_mark_node if the conversion was unsuccessful. Error and
3549 warning messages are issued under control of COMPLAIN. This
3550 conversion is for the Ith parameter in the parameter list. ARGS is
3551 the full set of template arguments deduced so far. */
3553 static tree
3555 tree arg,
3556 tree args,
3557 tsubst_flags_t complain,
3559 tree in_decl)
3560 {
3561 tree val;
3562 tree inner_args;
3569 {
3570 /* The template argument was the name of some
3571 member function. That's usually
3572 invalid, but static members are OK. In any
3573 case, grab the underlying fields/functions
3574 and issue an error later if required. */
3577 }
3597 {
3604 }
3606 {
3608 {
3610 {
3619 else
3621 }
3622 }
3624 }
3626 {
3628 {
3633 else
3635 }
3637 }
3640 {
3642 {
3644 /* The number of argument required is not known yet.
3645 Just accept it for now. */
3647 else
3648 {
3654 inner_args))
3655 {
3658 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3659 TEMPLATE_DECL. */
3663 }
3664 else
3665 {
3667 {
3671 }
3674 }
3675 }
3676 }
3677 else
3679 }
3680 else
3681 {
3688 /* We used to call digest_init here. However, digest_init
3689 will report errors, which we don't want when complain
3690 is zero. More importantly, digest_init will try too
3691 hard to convert things: for example, `0' should not be
3692 converted to pointer type at this point according to
3693 the standard. Accepting this is not merely an
3694 extension, since deciding whether or not these
3695 conversions can occur is part of determining which
3696 function template to call, or whether a given explicit
3697 argument specification is valid. */
3699 else
3707 }
3710 }
3712 /* Convert all template arguments to their appropriate types, and
3713 return a vector containing the innermost resulting template
3714 arguments. If any error occurs, return error_mark_node. Error and
3715 warning messages are issued under control of COMPLAIN.
3717 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3718 provided in ARGLIST, or else trailing parameters must have default
3719 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3720 deduction for any unspecified trailing arguments. */
3722 static tree
3724 tree args,
3725 tree in_decl,
3726 tsubst_flags_t complain,
3728 {
3730 tree inner_args;
3731 tree new_args;
3732 tree new_inner_args;
3740 && require_all_arguments
3742 {
3744 {
3750 }
3753 }
3758 {
3759 tree arg;
3760 tree parm;
3762 /* Get the Ith template parameter. */
3765 /* Calculate the Ith argument. */
3769 /* There must be a default arg in this case. */
3772 else
3778 else
3781 in_decl);
3784 lost++;
3786 }
3792 }
3794 /* Returns 1 if template args OT and NT are equivalent. */
3796 static int
3798 {
3803 /* For member templates */
3809 else
3811 }
3813 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3814 of template arguments. Returns 0 otherwise. */
3816 int
3818 {
3825 {
3831 }
3833 }
3835 /* Given class template name and parameter list, produce a user-friendly name
3836 for the instantiation. */
3840 {
3847 else
3851 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3852 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3860 {
3868 {
3871 }
3873 {
3875 {
3876 /* Already substituted with real template. Just output
3877 the template name here */
3880 {
3881 /* The template may be defined in a namespace, or
3882 may be a member template. */
3888 }
3890 }
3891 else
3892 /* Output the parameter declaration. */
3895 }
3896 else
3899 /* No need to check arglist against parmlist here; we did that
3900 in coerce_template_parms, called from lookup_template_class. */
3902 }
3903 {
3907 offset--;
3910 /* B<C<char> >, not B<C<char>> */
3913 }
3917 }
3919 static tree
3921 {
3923 /* Specializations have already had their names set up in
3924 lookup_template_class. */
3926 {
3929 /* For non-primary templates, the template parameters are
3930 implicit from their surrounding context. */
3932 {
3941 }
3942 }
3945 }
3947 static void
3949 {
3953 tree pt;
3959 /* We are called both from instantiate_decl, where we've already had a
3960 tinst_level pushed, and instantiate_template, where we haven't.
3961 Compensate. */
3970 else
3979 }
3982 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
3983 ARGLIST. Valid choices for FNS are given in the cp-tree.def
3984 documentation for TEMPLATE_ID_EXPR. */
3986 tree
3988 {
3989 tree type;
3997 {
4000 }
4009 {
4011 unknown_type_node,
4013 arglist);
4015 }
4022 }
4024 /* Within the scope of a template class S<T>, the name S gets bound
4025 (in build_self_reference) to a TYPE_DECL for the class, not a
4026 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4027 or one of its enclosing classes, and that type is a template,
4028 return the associated TEMPLATE_DECL. Otherwise, the original
4029 DECL is returned. */
4031 tree
4033 {
4040 }
4042 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4043 parameters, find the desired type.
4045 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4047 IN_DECL, if non-NULL, is the template declaration we are trying to
4048 instantiate.
4050 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4051 the class we are looking up.
4053 Issue error and warning messages under control of COMPLAIN.
4055 If the template class is really a local class in a template
4056 function, then the FUNCTION_CONTEXT is the function in which it is
4057 being instantiated. */
4059 tree
4061 tree arglist,
4062 tree in_decl,
4063 tree context,
4065 tsubst_flags_t complain)
4066 {
4068 tree t;
4073 {
4077 else
4078 {
4085 }
4088 }
4090 {
4093 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4094 an implicit typename for the second A. Deal with it. */
4099 {
4102 }
4103 }
4106 {
4109 }
4112 {
4116 }
4118 /* With something like `template <class T> class X class X { ... };'
4119 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
4120 We don't want to do that, but we have to deal with the situation,
4121 so let's give them some syntax errors to chew on instead of a
4122 crash. Alternatively D1 might not be a template type at all. */
4124 {
4128 }
4131 /* Make sure it's a user visible template, if it was named by
4132 the user. */
4135 {
4137 {
4141 }
4143 }
4148 {
4149 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4150 template arguments */
4152 tree parm;
4153 tree arglist2;
4157 /* Consider an example where a template template parameter declared as
4159 template <class T, class U = std::allocator<T> > class TT
4161 The template parameter level of T and U are one level larger than
4162 of TT. To proper process the default argument of U, say when an
4163 instantiation `TT<int>' is seen, we need to build the full
4164 arguments containing {int} as the innermost level. Outer levels,
4165 available when not appearing as default template argument, can be
4166 obtained from `current_template_args ()'.
4168 Suppose that TT is later substituted with std::vector. The above
4169 instantiation is `TT<int, std::allocator<T> >' with TT at
4170 level 1, and T at level 2, while the template arguments at level 1
4171 becomes {std::vector} and the inner level 2 is {int}. */
4185 }
4186 else
4187 {
4189 tree gen_tmpl;
4190 tree type_decl;
4203 {
4204 /* We've been given an incomplete set of template arguments.
4205 For example, given:
4207 template <class T> struct S1 {
4208 template <class U> struct S2 {};
4209 template <class U> struct S2<U*> {};
4210 };
4212 we will be called with an ARGLIST of `U*', but the
4213 TEMPLATE will be `template <class T> template
4214 <class U> struct S1<T>::S2'. We must fill in the missing
4215 arguments. */
4216 arglist
4218 arglist);
4220 }
4222 /* Now we should have enough arguments. */
4225 /* From here on, we're only interested in the most general
4226 template. */
4229 /* Calculate the BOUND_ARGS. These will be the args that are
4230 actually tsubst'd into the definition to create the
4231 instantiation. */
4233 {
4234 /* We have multiple levels of arguments to coerce, at once. */
4244 {
4249 /* Don't process further if one of the levels fails. */
4251 {
4252 /* Restore the ARGLIST to its full size. */
4255 }
4259 /* We temporarily reduce the length of the ARGLIST so
4260 that coerce_template_parms will see only the arguments
4261 corresponding to the template parameters it is
4262 examining. */
4264 }
4266 /* Restore the ARGLIST to its full size. */
4270 }
4271 else
4272 arglist
4279 /* We were unable to bind the arguments. */
4282 /* In the scope of a template class, explicit references to the
4283 template class refer to the type of the template, not any
4284 instantiation of it. For example, in:
4286 template <class T> class C { void f(C<T>); }
4288 the `C<T>' is just the same as `C'. Outside of the
4289 class, however, such a reference is an instantiation. */
4291 arglist))
4292 {
4296 {
4297 tree ctx;
4307 /* We're not in the scope of the class, so the
4308 TEMPLATE_TYPE is not the type we want after all. */
4310 found_ctx:;
4311 }
4312 }
4320 {
4323 /* Use the move-to-front heuristic to speed up future
4324 searches. */
4331 }
4333 /* This type is a "partial instantiation" if any of the template
4334 arguments still involve template parameters. Note that we set
4335 IS_PARTIAL_INSTANTIATION for partial specializations as
4336 well. */
4339 /* If the deduced arguments are invalid, then the binding
4340 failed. */
4344 complain))
4350 {
4355 }
4362 /* Create the type. */
4364 {
4366 {
4369 }
4370 else
4371 /* We don't want to call start_enum for this type, since
4372 the values for the enumeration constants may involve
4373 template parameters. And, no one should be interested
4374 in the enumeration constants for such a type. */
4376 }
4377 else
4378 {
4385 /* A local class. Make sure the decl gets registered properly. */
4388 }
4390 /* If we called start_enum or pushtag above, this information
4391 will already be set up. */
4393 {
4401 }
4402 else
4410 /* Set up the template information. We have to figure out which
4411 template is the immediate parent if this is a full
4412 instantiation. */
4415 /* This case is easy; there are no member templates involved. */
4417 else
4418 {
4419 /* This is a full instantiation of a member template. Look
4420 for a partial instantiation of which this is an instance. */
4424 {
4428 /* We only want partial instantiations, here, not
4429 specializations or full instantiations. */
4434 /* Temporarily reduce by one the number of levels in the
4435 ARGLIST and in FOUND so as to avoid comparing the
4436 last set of arguments. */
4440 /* See if the arguments match. If they do, then TMPL is
4441 the partial instantiation we want. */
4444 /* Restore the argument vectors to their full size. */
4449 {
4452 }
4453 }
4456 {
4457 /* There was no partial instantiation. This happens
4458 where C<T> is a member template of A<T> and it's used
4459 in something like
4461 template <typename T> struct B { A<T>::C<int> m; };
4462 B<float>;
4464 Create the partial instantiation.
4465 */
4469 }
4470 }
4479 /* Now that the type has been registered on the instantiations
4480 list, we set up the enumerators. Because the enumeration
4481 constants may involve the enumeration type itself, we make
4482 sure to register the type first, and then create the
4483 constants. That way, doing tsubst_expr for the enumeration
4484 constants won't result in recursive calls here; we'll find
4485 the instantiation and exit above. */
4488 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4489 is set up. */
4493 /* If the type makes use of template parameters, the
4494 code that generates debugging information will crash. */
4498 }
4500 }
4501 \f
4502 struct pair_fn_data
4503 {
4504 tree_fn_t fn;
4506 htab_t visited;
4507 };
4509 /* Called from for_each_template_parm via walk_tree. */
4511 static tree
4513 {
4524 {
4528 /* Fall through. */
4540 /* Since we're not going to walk subtrees, we have to do this
4541 explicitly here. */
4545 /* Fall through. */
4548 /* Check the return type. */
4552 /* Check the parameter types. Since default arguments are not
4553 instantiated until they are needed, the TYPE_ARG_TYPES may
4554 contain expressions that involve template parameters. But,
4555 no-one should be looking at them yet. And, once they're
4556 instantiated, they don't contain template parameters, so
4557 there's no point in looking at them then, either. */
4558 {
4559 tree parm;
4566 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4567 want walk_tree walking into them itself. */
4569 }
4584 /* Fall through. */
4599 /* Record template parameters such as `T' inside `TT<T>'. */
4602 /* Fall through. */
4614 /* A template template parameter is encountered. */
4619 /* Already substituted template template parameter */
4640 /* If there's no type, then this thing must be some expression
4641 involving template parameters. */
4661 /* If we do not handle this case specially, we end up walking
4662 the BINFO hierarchy, which is circular, and therefore
4663 confuses walk_tree. */
4672 }
4674 /* We didn't find any template parameters we liked. */
4676 }
4678 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4679 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4680 call FN with the parameter and the DATA.
4681 If FN returns nonzero, the iteration is terminated, and
4682 for_each_template_parm returns 1. Otherwise, the iteration
4683 continues. If FN never returns a nonzero value, the value
4684 returned by for_each_template_parm is 0. If FN is NULL, it is
4685 considered to be the function which always returns 1. */
4687 static int
4689 {
4693 /* Set up. */
4697 /* Walk the tree. (Conceptually, we would like to walk without
4698 duplicates, but for_each_template_parm_r recursively calls
4699 for_each_template_parm, so we would need to reorganize a fair
4700 bit to use walk_tree_without_duplicates, so we keep our own
4701 visited list.) */
4704 else
4706 NULL);
4708 for_each_template_parm_r,
4712 /* Clean up. */
4717 }
4719 /* Returns true if T depends on any template parameter. */
4721 int
4723 {
4747 else
4752 }
4754 /* Returns true if T depends on any template parameter with level LEVEL. */
4756 int
4758 {
4760 }
4764 #ifdef GATHER_STATISTICS
4766 #endif
4770 /* We're starting to instantiate D; record the template instantiation context
4771 for diagnostics and to restore it later. */
4773 int
4775 {
4779 {
4780 /* If the instantiation in question still has unbound template parms,
4781 we don't really care if we can't instantiate it, so just return.
4782 This happens with base instantiation for implicit `typename'. */
4787 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4793 }
4800 #ifdef GATHER_STATISTICS
4803 #endif
4807 }
4809 /* We're done instantiating this template; return to the instantiation
4810 context. */
4812 void
4814 {
4817 /* Restore the filename and line number stashed away when we started
4818 this instantiation. */
4826 }
4828 /* We're instantiating a deferred template; restore the template
4829 instantiation context in which the instantiation was requested, which
4830 is one step out from LEVEL. */
4832 static void
4834 {
4835 tree t;
4843 }
4845 /* Return the outermost template instantiation context, for use with
4846 -falt-external-templates. */
4848 tree
4850 {
4855 ;
4857 }
4859 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4860 vector of template arguments, as for tsubst.
4862 Returns an appropriate tsubst'd friend declaration. */
4864 static tree
4866 {
4867 tree new_friend;
4875 /* This was a friend declared with an explicit template
4876 argument list, e.g.:
4878 friend void f<>(T);
4880 to indicate that f was a template instantiation, not a new
4881 function declaration. Now, we have to figure out what
4882 instantiation of what template. */
4883 {
4885 tree new_args;
4886 tree tmpl;
4889 /* Friend functions are looked up in the containing namespace scope.
4890 We must enter that scope, to avoid finding member functions of the
4891 current cless with same name. */
4906 }
4910 /* The NEW_FRIEND will look like an instantiation, to the
4911 compiler, but is not an instantiation from the point of view of
4912 the language. For example, we might have had:
4914 template <class T> struct S {
4915 template <class U> friend void f(T, U);
4916 };
4918 Then, in S<int>, template <class U> void f(int, U) is not an
4919 instantiation of anything. */
4925 {
4929 }
4931 /* The mangled name for the NEW_FRIEND is incorrect. The function
4932 is not a template instantiation and should not be mangled like
4933 one. Therefore, we forget the mangling here; we'll recompute it
4934 later if we need it. */
4936 {
4939 }
4942 {
4943 tree old_decl;
4944 tree new_friend_template_info;
4945 tree new_friend_result_template_info;
4946 tree ns;
4949 /* We must save some information from NEW_FRIEND before calling
4950 duplicate decls since that function will free NEW_FRIEND if
4951 possible. */
4954 {
4955 /* This declaration is a `primary' template. */
4958 new_friend_is_defn
4960 new_friend_result_template_info
4962 }
4963 else
4964 {
4967 }
4969 /* Inside pushdecl_namespace_level, we will push into the
4970 current namespace. However, the friend function should go
4971 into the namespace of the template. */
4978 {
4979 /* This new friend declaration matched an existing
4980 declaration. For example, given:
4982 template <class T> void f(T);
4983 template <class U> class C {
4984 template <class T> friend void f(T) {}
4985 };
4987 the friend declaration actually provides the definition
4988 of `f', once C has been instantiated for some type. So,
4989 old_decl will be the out-of-class template declaration,
4990 while new_friend is the in-class definition.
4992 But, if `f' was called before this point, the
4993 instantiation of `f' will have DECL_TI_ARGS corresponding
4994 to `T' but not to `U', references to which might appear
4995 in the definition of `f'. Previously, the most general
4996 template for an instantiation of `f' was the out-of-class
4997 version; now it is the in-class version. Therefore, we
4998 run through all specialization of `f', adding to their
4999 DECL_TI_ARGS appropriately. In particular, they need a
5000 new set of outer arguments, corresponding to the
5001 arguments for this class instantiation.
5003 The same situation can arise with something like this:
5005 friend void f(int);
5006 template <class T> class C {
5007 friend void f(T) {}
5008 };
5010 when `C<int>' is instantiated. Now, `f(int)' is defined
5011 in the class. */
5014 /* On the other hand, if the in-class declaration does
5015 *not* provide a definition, then we don't want to alter
5016 existing definitions. We can just leave everything
5017 alone. */
5018 ;
5019 else
5020 {
5021 /* Overwrite whatever template info was there before, if
5022 any, with the new template information pertaining to
5023 the declaration. */
5029 old_decl);
5030 else
5031 {
5032 tree t;
5033 tree new_friend_args;
5042 {
5048 }
5050 /* Now, since specializations are always supposed to
5051 hang off of the most general template, we must move
5052 them. */
5055 {
5060 }
5061 }
5062 }
5064 /* The information from NEW_FRIEND has been merged into OLD_DECL
5065 by duplicate_decls. */
5067 }
5068 }
5070 {
5071 /* Check to see that the declaration is really present, and,
5072 possibly obtain an improved declaration. */
5078 }
5080 done:
5083 }
5085 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5086 template arguments, as for tsubst.
5088 Returns an appropriate tsubst'd friend type or error_mark_node on
5089 failure. */
5091 static tree
5093 {
5094 tree friend_type;
5095 tree tmpl;
5096 tree context;
5101 {
5104 else
5106 }
5108 /* First, we look for a class template. */
5111 /* But, if we don't find one, it might be because we're in a
5112 situation like this:
5114 template <class T>
5115 struct S {
5116 template <class U>
5117 friend struct S;
5118 };
5120 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5121 for `S<int>', not the TEMPLATE_DECL. */
5123 {
5126 }
5129 {
5130 /* The friend template has already been declared. Just
5131 check to see that the declarations match, and install any new
5132 default parameters. We must tsubst the default parameters,
5133 of course. We only need the innermost template parameters
5134 because that is all that redeclare_class_template will look
5135 at. */
5138 {
5139 tree parms;
5143 }
5146 }
5147 else
5148 {
5149 /* The friend template has not already been declared. In this
5150 case, the instantiation of the template class will cause the
5151 injection of this template into the global scope. */
5154 /* The new TMPL is not an instantiation of anything, so we
5155 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5156 the new type because that is supposed to be the corresponding
5157 template decl, i.e., TMPL. */
5164 /* Inject this template into the global scope. */
5166 }
5169 {
5172 else
5174 }
5177 }
5179 /* Returns zero if TYPE cannot be completed later due to circularity.
5180 Otherwise returns one. */
5182 static int
5184 {
5194 else
5196 }
5198 tree
5200 {
5202 tree typedecl;
5203 tree pbinfo;
5213 /* Figure out which template is being instantiated. */
5217 /* Figure out which arguments are being used to do the
5218 instantiation. */
5221 /* Determine what specialization of the original template to
5222 instantiate. */
5225 {
5230 {
5232 {
5235 }
5236 }
5239 }
5243 else
5246 /* If the template we're instantiating is incomplete, then clearly
5247 there's nothing we can do. */
5251 /* If we've recursively instantiated too many templates, stop. */
5255 /* Now we're really doing the instantiation. Mark the type as in
5256 the process of being defined. */
5259 /* We may be in the middle of deferred access check. Disable
5260 it now. */
5266 {
5267 /* This TYPE is actually an instantiation of a partial
5268 specialization. We replace the innermost set of ARGS with
5269 the arguments appropriate for substitution. For example,
5270 given:
5272 template <class T> struct S {};
5273 template <class T> struct S<T*> {};
5275 and supposing that we are instantiating S<int*>, ARGS will
5276 present be {int*} but we need {int}. */
5277 tree inner_args
5279 args);
5281 /* If there were multiple levels in ARGS, replacing the
5282 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5283 want, so we make a copy first. */
5285 {
5288 }
5289 else
5291 }
5295 /* Set the input location to the template definition. This is needed
5296 if tsubsting causes an error. */
5326 #ifdef ENABLE_CHECKING
5330 /* We should never instantiate a nested class before its enclosing
5331 class; we need to look up the nested class by name before we can
5332 instantiate it, and that lookup should instantiate the enclosing
5333 class. */
5335 #endif
5338 {
5345 /* We must enter the scope containing the type, as that is where
5346 the accessibility of types named in dependent bases are
5347 looked up from. */
5350 /* Substitute into each of the bases to determine the actual
5351 basetypes. */
5353 {
5354 tree base;
5355 tree access;
5356 tree pbase;
5361 /* Substitute to figure out the base class. */
5368 }
5370 /* The list is now in reverse order; correct that. */
5373 /* Now call xref_basetypes to set up all the base-class
5374 information. */
5378 }
5380 /* Now that our base classes are set up, enter the scope of the
5381 class, so that name lookups into base classes, etc. will work
5382 correctly. This is precisely analogous to what we do in
5383 begin_class_definition when defining an ordinary non-template
5384 class. */
5387 /* Now members are processed in the order of declaration. */
5390 {
5394 {
5396 {
5397 /* Build new CLASSTYPE_NESTED_UTDS. */
5401 tree newtag;
5408 {
5410 /* Unfortunately, lookup_template_class sets
5411 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5412 instantiation (i.e., for the type of a member
5413 template class nested within a template class.)
5414 This behavior is required for
5415 maybe_process_partial_specialization to work
5416 correctly, but is not accurate in this case;
5417 the TAG is not an instantiation of anything.
5418 (The corresponding TEMPLATE_DECL is an
5419 instantiation, but the TYPE is not.) */
5422 /* Now, we call pushtag to put this NEWTAG into the scope of
5423 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5424 pushtag calling push_template_decl. We don't have to do
5425 this for enums because it will already have been done in
5426 tsubst_enum. */
5430 }
5431 }
5434 {
5435 /* Build new TYPE_METHODS. */
5436 tree r;
5446 }
5447 else
5448 {
5449 /* Build new TYPE_FIELDS. */
5452 {
5453 tree r;
5455 /* The the file and line for this declaration, to
5456 assist in error message reporting. Since we
5457 called push_tinst_level above, we don't need to
5458 restore these. */
5467 {
5468 tree init;
5473 else
5476 finish_static_data_member_decl
5481 }
5483 {
5484 /* Determine whether R has a valid type and can be
5485 completed later. If R is invalid, then it is
5486 replaced by error_mark_node so that it will not be
5487 added to TYPE_FIELDS. */
5493 {
5496 }
5497 }
5499 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5500 such a thing will already have been added to the field
5501 list by tsubst_enum in finish_member_declaration in the
5502 CLASSTYPE_NESTED_UTDS case above. */
5506 {
5509 }
5510 }
5511 }
5512 }
5513 else
5514 {
5516 {
5517 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5520 tree new_friend_type;
5529 else
5530 {
5533 /* The call to xref_tag_from_type does injection for friend
5534 classes. */
5536 new_friend_type =
5539 }
5542 /* Trick make_friend_class into realizing that the friend
5543 we're adding is a template, not an ordinary class. It's
5544 important that we use make_friend_class since it will
5545 perform some error-checking and output cross-reference
5546 information. */
5555 }
5556 else
5557 {
5558 /* Build new DECL_FRIENDLIST. */
5559 tree r;
5567 }
5568 }
5569 }
5571 /* Set the file and line number information to whatever is given for
5572 the class itself. This puts error messages involving generated
5573 implicit functions at a predictable point, and the same point
5574 that would be used for non-template classes. */
5581 /* Clear this now so repo_template_used is happy. */
5585 /* Now that the class is complete, instantiate default arguments for
5586 any member functions. We don't do this earlier because the
5587 default arguments may reference members of the class. */
5591 /* Implicitly generated member functions will not have template
5592 information; they are not instantiations, but instead are
5593 created "fresh" for each instantiation. */
5606 }
5608 static tree
5610 {
5611 tree r;
5617 else
5618 {
5622 {
5623 /* Sometimes, one of the args was an expression involving a
5624 template constant parameter, like N - 1. Now that we've
5625 tsubst'd, we might have something like 2 - 1. This will
5626 confuse lookup_template_class, so we do constant folding
5627 here. We have to unset processing_template_decl, to fool
5628 tsubst_copy_and_build() into building an actual tree. */
5630 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5631 as simple as it's going to get, and trying to reprocess
5632 the trees will break. Once tsubst_expr et al DTRT for
5633 non-dependent exprs, this code can go away, as the type
5634 will always be set. */
5636 {
5643 }
5645 }
5646 }
5648 }
5650 /* Substitute ARGS into the vector or list of template arguments T. */
5652 static tree
5654 {
5660 {
5662 tree new_arg;
5666 else
5675 }
5685 }
5687 /* Return the result of substituting ARGS into the template parameters
5688 given by PARMS. If there are m levels of ARGS and m + n levels of
5689 PARMS, then the result will contain n levels of PARMS. For
5690 example, if PARMS is `template <class T> template <class U>
5691 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5692 result will be `template <int*, double, class V>'. */
5694 static tree
5696 {
5704 {
5705 tree new_vec =
5710 {
5721 }
5727 }
5730 }
5732 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5733 type T. If T is not an aggregate or enumeration type, it is
5734 handled as if by tsubst. IN_DECL is as for tsubst. If
5735 ENTERING_SCOPE is nonzero, T is the context for a template which
5736 we are presently tsubst'ing. Return the substituted value. */
5738 static tree
5740 tree args,
5741 tsubst_flags_t complain,
5742 tree in_decl,
5744 {
5749 {
5754 /* Else fall through. */
5758 {
5759 tree argvec;
5760 tree context;
5761 tree r;
5763 /* First, determine the context for the type we are looking
5764 up. */
5770 /* Then, figure out what arguments are appropriate for the
5771 type we are trying to find. For example, given:
5773 template <class T> struct S;
5774 template <class T, class U> void f(T, U) { S<U> su; }
5776 and supposing that we are instantiating f<int, double>,
5777 then our ARGS will be {int, double}, but, when looking up
5778 S we only want {double}. */
5788 }
5789 else
5790 /* This is not a template type, so there's nothing to do. */
5795 }
5796 }
5798 /* Substitute into the default argument ARG (a default argument for
5799 FN), which has the indicated TYPE. */
5801 tree
5803 {
5804 /* This default argument came from a template. Instantiate the
5805 default argument here, not in tsubst. In the case of
5806 something like:
5808 template <class T>
5809 struct S {
5810 static T t();
5811 void f(T = t());
5812 };
5814 we must be careful to do name lookup in the scope of S<T>,
5815 rather than in the current class.
5817 ??? current_class_type affects a lot more than name lookup. This is
5818 very fragile. Fortunately, it will go away when we do 2-phase name
5819 binding properly. */
5821 /* FN is already the desired FUNCTION_DECL. */
5829 /* Make sure the default argument is reasonable. */
5833 }
5835 /* Substitute into all the default arguments for FN. */
5837 static void
5839 {
5840 tree arg;
5841 tree tmpl_args;
5845 /* If this function is not yet instantiated, we certainly don't need
5846 its default arguments. */
5851 arg;
5857 }
5859 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5860 (already computed) substitution of ARGS into TREE_TYPE (T), if
5861 appropriate. Return the result of the substitution. Issue error
5862 and warning messages under control of COMPLAIN. */
5864 static tree
5866 {
5867 location_t saved_loc;
5871 /* Set the filename and linenumber to improve error-reporting. */
5876 {
5878 {
5879 /* We can get here when processing a member template function
5880 of a template class. */
5882 tree spec;
5886 {
5887 /* We might already have an instance of this template.
5888 The ARGS are for the surrounding class type, so the
5889 full args contain the tsubst'd args for the context,
5890 plus the innermost args from the template decl. */
5894 tree full_args;
5899 /* tsubst_template_args doesn't copy the vector if
5900 nothing changed. But, *something* should have
5901 changed. */
5906 {
5909 }
5910 }
5912 /* Make a new template decl. It will be similar to the
5913 original, but will record the current template arguments.
5914 We also create a new function declaration, which is just
5915 like the old one, but points to this new template, rather
5916 than the old one. */
5922 {
5927 }
5936 {
5945 }
5946 else
5947 {
5956 }
5962 /* The template parameters for this new template are all the
5963 template parameters for the old template, except the
5964 outermost level of parameters. */
5967 complain);
5973 /* Record this non-type partial instantiation. */
5976 }
5980 {
5981 tree ctx;
5984 tree gen_tmpl;
5989 /* Nobody should be tsubst'ing into non-template functions. */
5993 {
5994 tree spec;
5997 /* If T is not dependent, just return it. We have to
5998 increment PROCESSING_TEMPLATE_DECL because
5999 value_dependent_expression_p assumes that nothing is
6000 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6007 /* Calculate the most general template of which R is a
6008 specialization, and the complete set of arguments used to
6009 specialize R. */
6015 /* Check to see if we already have this specialization. */
6019 {
6022 }
6024 /* We can see more levels of arguments than parameters if
6025 there was a specialization of a member template, like
6026 this:
6028 template <class T> struct S { template <class U> void f(); }
6029 template <> template <class U> void S<int>::f(U);
6031 Here, we'll be substituting into the specialization,
6032 because that's where we can find the code we actually
6033 want to generate, but we'll have enough arguments for
6034 the most general template.
6036 We also deal with the peculiar case:
6038 template <class T> struct S {
6039 template <class U> friend void f();
6040 };
6041 template <class U> void f() {}
6042 template S<int>;
6043 template void f<double>();
6045 Here, the ARGS for the instantiation of will be {int,
6046 double}. But, we only need as many ARGS as there are
6047 levels of template parameters in CODE_PATTERN. We are
6048 careful not to get fooled into reducing the ARGS in
6049 situations like:
6051 template <class T> struct S { template <class U> void f(U); }
6052 template <class T> template <> void S<T>::f(int) {}
6054 which we can spot because the pattern will be a
6055 specialization in this case. */
6057 parms_depth =
6062 }
6063 else
6064 {
6065 /* This special case arises when we have something like this:
6067 template <class T> struct S {
6068 friend void f<int>(int, double);
6069 };
6071 Here, the DECL_TI_TEMPLATE for the friend declaration
6072 will be an IDENTIFIER_NODE. We are being called from
6073 tsubst_friend_function, and we want only to create a
6074 new decl (R) with appropriate types so that we can call
6075 determine_specialization. */
6077 }
6080 {
6083 else
6087 }
6088 else
6089 {
6092 }
6097 /* We do NOT check for matching decls pushed separately at this
6098 point, as they may not represent instantiations of this
6099 template, and in any case are considered separate under the
6100 discrete model. */
6104 /* Clear out the mangled name and RTL for the instantiation. */
6111 /* Type-conversion operator. Reconstruct the name, in
6112 case it's the name of one of the template's parameters. */
6130 {
6135 }
6137 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6138 this in the special friend case mentioned above where
6139 GEN_TMPL is NULL. */
6141 {
6147 /* We're not supposed to instantiate default arguments
6148 until they are called, for a template. But, for a
6149 declaration like:
6151 template <class T> void f ()
6152 { extern void g(int i = T()); }
6154 we should do the substitution when the template is
6155 instantiated. We handle the member function case in
6156 instantiate_class_template since the default arguments
6157 might refer to other members of the class. */
6162 }
6164 /* Copy the list of befriending classes. */
6168 {
6172 in_decl);
6173 }
6176 {
6180 /* If this is an instantiation of a member template, clone it.
6181 If it isn't, that'll be handled by
6182 clone_constructors_and_destructors. */
6185 }
6189 }
6193 {
6202 {
6205 else
6208 }
6217 }
6221 {
6226 /* We don't have to set DECL_CONTEXT here; it is set by
6227 finish_member_declaration. */
6233 }
6237 {
6239 /* It is not a dependent using decl any more. */
6246 }
6252 {
6253 /* If this is the canonical decl, we don't have to mess with
6254 instantiations, and often we can't (for typename, template
6255 type parms and such). Note that TYPE_NAME is not correct for
6256 the above test if we've copied the type for a typedef. */
6259 }
6261 /* Fall through. */
6264 {
6267 tree spec;
6269 tree ctx;
6272 /* Assume this is a non-local variable. */
6277 complain,
6281 else
6282 {
6283 /* Subsequent calls to pushdecl will fill this in. */
6286 }
6288 /* Check to see if we already have this specialization. */
6290 {
6295 }
6296 else
6300 {
6303 }
6307 {
6311 }
6317 /* Clear out the mangled name and RTL for the instantiation. */
6321 /* Don't try to expand the initializer until someone tries to use
6322 this variable; otherwise we run into circular dependencies. */
6327 /* Even if the original location is out of scope, the newly
6328 substituted one is not. */
6330 {
6333 }
6336 {
6337 /* A static data member declaration is always marked
6338 external when it is declared in-class, even if an
6339 initializer is present. We mimic the non-template
6340 processing here. */
6346 }
6347 else
6353 /* Compute the size, alignment, etc. of R. */
6355 }
6360 }
6362 /* Restore the file and line information. */
6366 }
6368 /* Substitute into the ARG_TYPES of a function type. */
6370 static tree
6372 tree args,
6373 tsubst_flags_t complain,
6374 tree in_decl)
6375 {
6376 tree remaining_arg_types;
6377 tree type;
6391 {
6393 {
6397 }
6399 }
6401 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6402 top-level qualifiers as required. */
6405 /* Note that we do not substitute into default arguments here. The
6406 standard mandates that they be instantiated only when needed,
6407 which is done in build_over_call. */
6409 remaining_arg_types);
6411 }
6413 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6414 *not* handle the exception-specification for FNTYPE, because the
6415 initial substitution of explicitly provided template parameters
6416 during argument deduction forbids substitution into the
6417 exception-specification:
6419 [temp.deduct]
6421 All references in the function type of the function template to the
6422 corresponding template parameters are replaced by the specified tem-
6423 plate argument values. If a substitution in a template parameter or
6424 in the function type of the function template results in an invalid
6425 type, type deduction fails. [Note: The equivalent substitution in
6426 exception specifications is done only when the function is instanti-
6427 ated, at which point a program is ill-formed if the substitution
6428 results in an invalid type.] */
6430 static tree
6432 tree args,
6433 tsubst_flags_t complain,
6434 tree in_decl)
6435 {
6436 tree return_type;
6437 tree arg_types;
6438 tree fntype;
6440 /* The TYPE_CONTEXT is not used for function/method types. */
6443 /* Substitute the return type. */
6448 /* Substitute the argument types. */
6454 /* Construct a new type node and return it. */
6457 else
6458 {
6461 {
6462 /* [temp.deduct]
6464 Type deduction may fail for any of the following
6465 reasons:
6467 -- Attempting to create "pointer to member of T" when T
6468 is not a class type. */
6471 r);
6473 }
6477 }
6482 }
6484 /* Substitute into the PARMS of a call-declarator. */
6486 static tree
6488 tree args,
6489 tsubst_flags_t complain,
6490 tree in_decl)
6491 {
6492 tree new_parms;
6493 tree type;
6494 tree defarg;
6502 /* Figure out the type of this parameter. */
6505 /* Figure out the default argument as well. Note that we use
6506 tsubst_expr since the default argument is really an expression. */
6509 /* Chain this parameter on to the front of those we have already
6510 processed. We don't use hash_tree_cons because that function
6511 doesn't check TREE_PARMLIST. */
6514 /* And note that these are parameters. */
6518 }
6520 /* Take the tree structure T and replace template parameters used
6521 therein with the argument vector ARGS. IN_DECL is an associated
6522 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6523 Issue error and warning messages under control of COMPLAIN. Note
6524 that we must be relatively non-tolerant of extensions here, in
6525 order to preserve conformance; if we allow substitutions that
6526 should not be allowed, we may allow argument deductions that should
6527 not succeed, and therefore report ambiguous overload situations
6528 where there are none. In theory, we could allow the substitution,
6529 but indicate that it should have failed, and allow our caller to
6530 make sure that the right thing happens, but we don't try to do this
6531 yet.
6533 This function is used for dealing with types, decls and the like;
6534 for expressions, use tsubst_expr or tsubst_copy. */
6536 static tree
6538 {
6550 else
6569 {
6596 {
6599 /* The array dimension behaves like a non-type template arg,
6600 in that we want to fold it as much as possible. */
6606 {
6607 /* Still allow an explicit array of size zero. */
6610 }
6614 {
6615 /* [temp.deduct]
6617 Type deduction may fail for any of the following
6618 reasons:
6620 Attempting to create an array with a size that is
6621 zero or negative. */
6626 }
6629 }
6635 {
6645 {
6648 }
6649 else
6650 {
6653 }
6656 {
6666 {
6668 {
6670 return cp_build_qualified_type_real
6673 }
6675 {
6676 /* We are processing a type constructed from
6677 a template template parameter. */
6683 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6684 we are resolving nested-types in the signature of
6685 a member function templates.
6686 Otherwise ARG is a TEMPLATE_DECL and is the real
6687 template to be instantiated. */
6695 complain);
6696 return cp_build_qualified_type_real
6698 }
6699 else
6700 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6702 }
6703 }
6704 else
6708 /* This can happen during the attempted tsubst'ing in
6709 unify. This means that we don't yet have any information
6710 about the template parameter in question. */
6713 /* If we get here, we must have been looking at a parm for a
6714 more deeply nested template. Make a new version of this
6715 template parameter, but with a lower level. */
6717 {
6722 {
6724 r = cp_build_qualified_type_real
6728 }
6729 else
6730 {
6741 {
6749 }
6750 }
6759 }
6762 }
6765 {
6773 {
6777 }
6780 {
6784 }
6787 {
6791 }
6797 {
6800 }
6801 else
6804 }
6807 {
6808 /* A binfo node. We always need to make a copy, of the node
6809 itself and of its BINFO_BASETYPES. */
6813 /* Make sure type isn't a typedef copy. */
6818 {
6823 }
6825 }
6827 /* Otherwise, a vector of template arguments. */
6832 {
6841 /* [temp.deduct]
6843 Type deduction may fail for any of the following
6844 reasons:
6846 -- Attempting to create a pointer to reference type.
6847 -- Attempting to create a reference to a reference type or
6848 a reference to void. */
6851 {
6854 /* We keep track of the last time we issued this error
6855 message to avoid spewing a ton of messages during a
6856 single bad template instantiation. */
6860 {
6863 else
6866 type);
6868 }
6871 }
6873 {
6877 }
6878 else
6883 /* Will this ever be needed for TYPE_..._TO values? */
6887 }
6889 {
6892 {
6893 /* [temp.deduct]
6895 Type deduction may fail for any of the following
6896 reasons:
6898 -- Attempting to create "pointer to member of T" when T
6899 is not a class type. */
6903 }
6905 {
6910 }
6913 {
6914 /* This is really a method type. The cv qualifiers of the
6915 this pointer should _not_ be determined by the cv
6916 qualifiers of the class type. They should be held
6917 somewhere in the FUNCTION_TYPE, but we don't do that at
6918 the moment. Consider
6919 typedef void (Func) () const;
6921 template <typename T1> void Foo (Func T1::*);
6923 */
6924 tree method_type;
6930 }
6931 else
6934 complain);
6935 }
6938 {
6939 tree fntype;
6940 tree raises;
6946 /* Substitute the exception specification. */
6949 {
6954 else
6956 {
6963 }
6965 }
6967 }
6969 {
6974 /* As an optimization, we avoid regenerating the array type if
6975 it will obviously be the same as T. */
6979 /* These checks should match the ones in grokdeclarator.
6981 [temp.deduct]
6983 The deduction may fail for any of the following reasons:
6985 -- Attempting to create an array with an element type that
6986 is void, a function type, or a reference type, or [DR337]
6987 an abstract class type. */
6991 {
6995 }
6997 {
7000 type);
7002 }
7006 }
7010 {
7018 }
7022 {
7028 }
7031 {
7041 {
7044 ctx);
7046 }
7048 {
7049 /* Normally, make_typename_type does not require that the CTX
7050 have complete type in order to allow things like:
7052 template <class T> struct S { typename S<T>::X Y; };
7054 But, such constructs have already been resolved by this
7055 point, so here CTX really should have complete type, unless
7056 it's a partial instantiation. */
7059 {
7063 }
7064 }
7071 {
7074 }
7076 return cp_build_qualified_type_real
7078 }
7081 {
7090 }
7093 {
7098 }
7101 {
7106 }
7109 {
7116 }
7119 {
7121 tree e2 = (tsubst_call_declarator_parms
7131 }
7134 {
7141 }
7144 {
7145 tree type;
7148 in_decl));
7152 complain);
7153 }
7159 }
7160 }
7162 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7163 type of the expression on the left-hand side of the "." or "->"
7164 operator. */
7166 static tree
7169 {
7170 tree name;
7171 tree qualifying_scope;
7172 tree fns;
7176 /* A baselink indicates a function from a base class. The
7177 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7178 non-dependent types; otherwise, the lookup could not have
7179 succeeded. However, they may indicate bases of the template
7180 class, rather than the instantiated class.
7182 In addition, lookups that were not ambiguous before may be
7183 ambiguous now. Therefore, we perform the lookup again. */
7187 {
7194 }
7201 template_args);
7205 qualifying_scope,
7206 object_type);
7207 }
7209 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7210 true if the qualified-id will be a postfix-expression in-and-of
7211 itself; false if more of the postfix-expression follows the
7212 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7213 of "&". */
7215 static tree
7219 {
7220 tree expr;
7221 tree scope;
7222 tree name;
7224 tree template_args;
7228 /* Figure out what name to look up. */
7231 {
7238 }
7239 else
7240 {
7243 }
7245 /* Substitute into the qualifying scope. When there are no ARGS, we
7246 are just trying to simplify a non-dependent expression. In that
7247 case the qualifying scope may be dependent, and, in any case,
7248 substituting will not help. */
7251 {
7254 }
7255 else
7261 {
7265 {
7267 {
7271 }
7273 }
7274 }
7278 scope);
7280 /* Remember that there was a reference to this entity. */
7282 {
7286 }
7294 {
7295 expr = (adjust_result_of_qualified_name_lookup
7298 }
7301 }
7303 /* Like tsubst, but deals with expressions. This function just replaces
7304 template parms; to finish processing the resultant expression, use
7305 tsubst_expr. */
7307 static tree
7309 {
7311 tree r;
7319 {
7326 {
7327 tree enum_type;
7328 tree v;
7332 /* There is no need to substitute into namespace-scope
7333 enumerators. */
7337 /* Unfortunately, we cannot just call lookup_name here.
7338 Consider:
7340 template <int I> int f() {
7341 enum E { a = I };
7342 struct S { void g() { E e = a; } };
7343 };
7345 When we instantiate f<7>::S::g(), say, lookup_name is not
7346 clever enough to find f<7>::a. */
7347 enum_type
7357 /* We didn't find the name. That should never happen; if
7358 name-lookup found it during preliminary parsing, we
7359 should find it again here during instantiation. */
7361 }
7366 {
7367 tree ctx;
7373 }
7395 {
7396 /* Template template argument like the following example need
7397 special treatment:
7399 template <template <class> class TT> struct C {};
7400 template <class T> struct D {
7401 template <class U> struct E {};
7402 C<E> c; // #1
7403 };
7404 D<int> d; // #2
7406 We are processing the template argument `E' in #1 for
7407 the template instantiation #2. Originally, `E' is a
7408 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7409 have to substitute this with one having context `D<int>'. */
7413 }
7414 else
7415 /* Ordinary template template argument. */
7424 return build1
7441 return build1
7446 {
7447 tree object;
7448 tree name;
7453 {
7457 }
7460 {
7468 }
7473 in_decl);
7474 else
7477 }
7517 return build_nt
7526 in_decl),
7527 NULL_TREE);
7530 /* This processing should really occur in tsubst_expr. However,
7531 tsubst_expr does not recurse into expressions, since it
7532 assumes that there aren't any statements inside them. So, we
7533 need to expand the STMT_EXPR here. */
7535 {
7541 }
7548 {
7549 r = build_nt
7554 }
7557 {
7558 r = build_nt
7564 }
7567 {
7568 r = build_nt
7574 }
7577 {
7578 /* Substituted template arguments */
7587 }
7590 {
7610 }
7634 {
7637 }
7638 else
7642 {
7643 r = build_constructor
7648 }
7652 in_decl),
7657 }
7658 }
7660 /* Like tsubst_copy for expressions, etc. but also does semantic
7661 processing. */
7663 static tree
7665 {
7667 tsubst_flags_t stmt_expr
7682 {
7696 {
7697 tree r;
7704 else
7707 }
7716 {
7717 tree decl;
7718 tree init;
7725 {
7728 tree decl;
7736 else
7738 }
7739 else
7740 {
7744 {
7747 /* By marking the declaration as instantiated, we avoid
7748 trying to instantiate it. Since instantiate_decl can't
7749 handle local variables, and since we've already done
7750 all that needs to be done, that's the right thing to
7751 do. */
7756 /* Anonymous aggregates are a special case. */
7758 else
7759 {
7763 {
7764 /* For __PRETTY_FUNCTION__ we have to adjust the
7765 initializer. */
7769 }
7770 else
7773 }
7774 }
7775 }
7777 /* A DECL_STMT can also be used as an expression, in the condition
7778 clause of an if/for/while construct. If we aren't followed by
7779 another statement, return our decl. */
7782 }
7786 {
7794 stmt);
7799 }
7803 {
7808 stmt);
7811 }
7815 {
7822 stmt);
7823 }
7827 {
7832 stmt);
7835 {
7838 }
7841 {
7845 }
7848 }
7852 {
7856 else
7861 in_decl);
7865 else
7867 }
7881 {
7882 tree val;
7890 }
7897 in_decl));
7914 /* Computed goto's must be tsubst'd into. On the other hand,
7915 non-computed gotos must not be; the identifier in question
7916 will have no binding. */
7918 else
7925 tmp = finish_asm_stmt
7937 {
7943 stmt);
7944 }
7945 else
7946 {
7949 else
7956 else
7962 else
7964 }
7968 {
7969 tree decl;
7974 {
7977 /* Prevent instantiate_decl from trying to instantiate
7978 this variable. We've already done all that needs to be
7979 done. */
7981 }
7982 else
7987 }
7997 }
8000 }
8002 /* T is a postfix-expression that is not being used in a function
8003 call. Return the substituted version of T. */
8005 static tree
8007 tsubst_flags_t complain,
8008 tree in_decl)
8009 {
8013 else
8018 }
8020 /* Like tsubst but deals with expressions and performs semantic
8021 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8023 tree
8025 tree args,
8026 tsubst_flags_t complain,
8027 tree in_decl,
8029 {
8030 #define RECUR(NODE) \
8033 tree op1;
8039 {
8042 /* Fall through. */
8044 {
8045 tree decl;
8046 cp_id_kind idk;
8047 tree qualifying_class;
8052 {
8055 }
8057 /* Look up the name. */
8060 /* By convention, expressions use ERROR_MARK_NODE to indicate
8061 failure, not NULL_TREE. */
8077 }
8080 {
8081 tree object;
8089 {
8092 }
8093 else
8100 else
8102 }
8108 return build_functional_cast
8113 return build_reinterpret_cast
8118 return build_const_cast
8123 return build_dynamic_cast
8128 return build_static_cast
8154 else
8156 in_decl);
8192 return build_x_binary_op
8204 /* new-type-id */
8209 /* Remember that there was a reference to this entity. */
8218 {
8219 /* When there are no ARGS, we are trying to evaluate a
8220 non-dependent expression from the parser. Trying to do
8221 the substitutions may not work. */
8224 }
8225 else
8226 {
8230 }
8233 else
8237 return build_x_modify_expr
8245 /* Remember that there was a reference to this entity. */
8251 return build_new
8258 return delete_sanity
8269 {
8270 tree function;
8271 tree call_args;
8276 /* When we parsed the expression, we determined whether or
8277 not Koenig lookup should be performed. */
8280 {
8285 }
8286 else
8287 {
8292 in_decl,
8296 }
8307 {
8310 }
8312 /* Remember that there was a reference to this entity. */
8321 {
8326 else
8332 }
8335 koenig_p);
8336 }
8339 return build_x_conditional_expr
8345 return finish_pseudo_destructor_expr
8351 {
8371 }
8374 {
8375 tree object;
8376 tree member;
8380 /* Remember that there was a reference to this entity. */
8389 else
8393 {
8396 NULL_TREE,
8401 object,
8403 }
8406 {
8407 tree tmpl;
8408 tree args;
8410 /* Lookup the template functions now that we know what the
8411 scope is. */
8420 args);
8421 else
8422 {
8425 }
8426 }
8431 }
8434 return build_throw
8438 {
8439 tree r;
8440 tree elts;
8444 /* digest_init will do the wrong thing if we let it. */
8449 /* We do not want to process the purpose of aggregate
8450 initializers as they are identifier nodes which will be
8451 looked up by digest_init. */
8454 elts;
8456 {
8464 }
8472 }
8475 {
8480 }
8488 else
8489 /* If there are no ARGS, then we are evaluating a
8490 non-dependent expression. If the expression is
8491 non-dependent, the variable must be a constant. */
8498 in_decl));
8502 }
8504 #undef RECUR
8505 }
8507 /* Verify that the instantiated ARGS are valid. For type arguments,
8508 make sure that the type's linkage is ok. For non-type arguments,
8509 make sure they are constants if they are integral or enumerations.
8510 Emit an error under control of COMPLAIN, and return TRUE on error. */
8512 static bool
8514 {
8519 {
8523 {
8524 /* [basic.link]: A name with no linkage (notably, the name
8525 of a class or enumeration declared in a local scope)
8526 shall not be used to declare an entity with linkage.
8527 This implies that names with no linkage cannot be used as
8528 template arguments. */
8532 {
8537 else
8540 }
8541 /* In order to avoid all sorts of complications, we do not
8542 allow variably-modified types as template arguments. */
8544 {
8548 }
8549 }
8550 /* A non-type argument of integral or enumerated type must be a
8551 constant. */
8555 {
8559 }
8560 }
8564 }
8566 /* Instantiate the indicated variable or function template TMPL with
8567 the template arguments in TARG_PTR. */
8569 tree
8571 {
8572 tree fndecl;
8573 tree gen_tmpl;
8574 tree spec;
8581 /* If this function is a clone, handle it specially. */
8583 {
8585 complain);
8586 tree clone;
8588 /* Look for the clone. */
8594 /* We should always have found the clone by now. */
8597 }
8599 /* Check to see if we already have this specialization. */
8606 {
8607 /* The TMPL is a partial instantiation. To get a full set of
8608 arguments we must add the arguments used to perform the
8609 partial instantiation. */
8611 targ_ptr);
8613 /* Check to see if we already have this specialization. */
8617 }
8620 complain))
8623 /* We are building a FUNCTION_DECL, during which the access of its
8624 parameters and return types have to be checked. However this
8625 FUNCTION_DECL which is the desired context for access checking
8626 is not built yet. We solve this chicken-and-egg problem by
8627 deferring all checks until we have the FUNCTION_DECL. */
8630 /* Substitute template parameters. */
8634 /* Now we know the specialization, compute access previously
8635 deferred. */
8641 /* The DECL_TI_TEMPLATE should always be the immediate parent
8642 template, not the most general template. */
8645 /* If we've just instantiated the main entry point for a function,
8646 instantiate all the alternate entry points as well. We do this
8647 by cloning the instantiation of the main entry point, not by
8648 instantiating the template clones. */
8653 }
8655 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8656 arguments that are being used when calling it. TARGS is a vector
8657 into which the deduced template arguments are placed.
8659 Return zero for success, 2 for an incomplete match that doesn't resolve
8660 all the types, and 1 for complete failure. An error message will be
8661 printed only for an incomplete match.
8663 If FN is a conversion operator, or we are trying to produce a specific
8664 specialization, RETURN_TYPE is the return type desired.
8666 The EXPLICIT_TARGS are explicit template arguments provided via a
8667 template-id.
8669 The parameter STRICT is one of:
8671 DEDUCE_CALL:
8672 We are deducing arguments for a function call, as in
8673 [temp.deduct.call].
8675 DEDUCE_CONV:
8676 We are deducing arguments for a conversion function, as in
8677 [temp.deduct.conv].
8679 DEDUCE_EXACT:
8680 We are deducing arguments when doing an explicit instantiation
8681 as in [temp.explicit], when determining an explicit specialization
8682 as in [temp.expl.spec], or when taking the address of a function
8683 template, as in [temp.deduct.funcaddr].
8685 DEDUCE_ORDER:
8686 We are deducing arguments when calculating the partial
8687 ordering between specializations of function or class
8688 templates, as in [temp.func.order] and [temp.class.order].
8690 LEN is the number of parms to consider before returning success, or -1
8691 for all. This is used in partial ordering to avoid comparing parms for
8692 which no actual argument was passed, since they are not considered in
8693 overload resolution (and are explicitly excluded from consideration in
8694 partial ordering in [temp.func.order]/6). */
8696 int
8698 tree explicit_targs,
8699 tree targs,
8700 tree args,
8701 tree return_type,
8702 unification_kind_t strict,
8704 {
8705 tree parms;
8706 tree fntype;
8713 {
8714 /* [temp.deduct]
8716 The specified template arguments must match the template
8717 parameters in kind (i.e., type, nontype, template), and there
8718 must not be more arguments than there are parameters;
8719 otherwise type deduction fails.
8721 Nontype arguments must match the types of the corresponding
8722 nontype template parameters, or must be convertible to the
8723 types of the corresponding nontype parameters as specified in
8724 _temp.arg.nontype_, otherwise type deduction fails.
8726 All references in the function type of the function template
8727 to the corresponding template parameters are replaced by the
8728 specified template argument values. If a substitution in a
8729 template parameter or in the function type of the function
8730 template results in an invalid type, type deduction fails. */
8732 tree converted_args;
8735 converted_args
8742 /* Substitute the explicit args into the function type. This is
8743 necessary so that, for instance, explicitly declared function
8744 arguments can match null pointed constants. If we were given
8745 an incomplete set of explicit args, we must not do semantic
8746 processing during substitution as we could create partial
8747 instantiations. */
8756 /* Place the explicitly specified arguments in TARGS. */
8759 }
8762 /* Never do unification on the 'this' parameter. */
8767 {
8768 /* We've been given a return type to match, prepend it. */
8773 }
8775 /* We allow incomplete unification without an error message here
8776 because the standard doesn't seem to explicitly prohibit it. Our
8777 callers must be ready to deal with unification failures in any
8778 event. */
8784 /* All is well so far. Now, check:
8786 [temp.deduct]
8788 When all template arguments have been deduced, all uses of
8789 template parameters in nondeduced contexts are replaced with
8790 the corresponding deduced argument values. If the
8791 substitution results in an invalid type, as described above,
8792 type deduction fails. */
8798 }
8800 /* Adjust types before performing type deduction, as described in
8801 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8802 sections are symmetric. PARM is the type of a function parameter
8803 or the return type of the conversion function. ARG is the type of
8804 the argument passed to the call, or the type of the value
8805 initialized with the result of the conversion function. */
8807 static int
8811 {
8815 {
8820 {
8821 /* Swap PARM and ARG throughout the remainder of this
8822 function; the handling is precisely symmetric since PARM
8823 will initialize ARG rather than vice versa. */
8828 }
8831 /* There is nothing to do in this case. */
8835 /* DR 214. [temp.func.order] is underspecified, and leads to no
8836 ordering between things like `T *' and `T const &' for `U *'.
8837 The former has T=U and the latter T=U*. The former looks more
8838 specialized and John Spicer considers it well-formed (the EDG
8839 compiler accepts it).
8841 John also confirms that deduction should proceed as in a function
8842 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8843 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8844 to an actual call can have such a type.
8846 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8847 If only ARG is a REFERENCE_TYPE, we look through that and then
8848 proceed as with DEDUCE_CALL (which could further convert it). */
8850 {
8854 }
8858 }
8861 {
8862 /* [temp.deduct.call]
8864 If P is not a reference type:
8866 --If A is an array type, the pointer type produced by the
8867 array-to-pointer standard conversion (_conv.array_) is
8868 used in place of A for type deduction; otherwise,
8870 --If A is a function type, the pointer type produced by
8871 the function-to-pointer standard conversion
8872 (_conv.func_) is used in place of A for type deduction;
8873 otherwise,
8875 --If A is a cv-qualified type, the top level
8876 cv-qualifiers of A's type are ignored for type
8877 deduction. */
8882 else
8884 }
8886 /* [temp.deduct.call]
8888 If P is a cv-qualified type, the top level cv-qualifiers
8889 of P's type are ignored for type deduction. If P is a
8890 reference type, the type referred to by P is used for
8891 type deduction. */
8894 {
8897 }
8899 /* DR 322. For conversion deduction, remove a reference type on parm
8900 too (which has been swapped into ARG). */
8905 }
8907 /* Most parms like fn_type_unification.
8909 If SUBR is 1, we're being called recursively (to unify the
8910 arguments of a function or method parameter of a function
8911 template). */
8913 static int
8915 tree targs,
8916 tree xparms,
8917 tree xargs,
8919 unification_kind_t strict,
8922 {
8938 {
8958 }
8963 again:
8970 && args
8972 {
8981 /* We can't deduce anything from this, but we might get all the
8982 template args from other function args. */
8985 /* Conversions will be performed on a function argument that
8986 corresponds with a function parameter that contains only
8987 non-deducible template parameters and explicitly specified
8988 template parameters. */
8990 {
8991 tree type;
8995 else
8999 {
9002 }
9003 else
9004 /* It might work; we shouldn't check now, because we might
9005 get into infinite recursion. Overload resolution will
9006 handle it. */
9010 }
9013 {
9016 {
9017 /* [temp.deduct.type] A template-argument can be deduced from
9018 a pointer to function or pointer to member function
9019 argument if the set of overloaded functions does not
9020 contain function templates and at most one of a set of
9021 overloaded functions provides a unique match. */
9028 }
9032 }
9034 {
9042 }
9044 /* Are we done with the interesting parms? */
9047 }
9048 /* Fail if we've reached the end of the parm list, and more args
9049 are present, and the parm list isn't variadic. */
9052 /* Fail if parms are left and they don't have default values. */
9058 done:
9062 {
9065 /* If this is an undeduced nontype parameter that depends on
9066 a type parameter, try another pass; its type may have been
9067 deduced from a later argument than the one from which
9068 this parameter can be deduced. */
9077 }
9079 }
9081 /* Subroutine of type_unification_real. Args are like the variables at the
9082 call site. ARG is an overloaded function (or template-id); we try
9083 deducing template args from each of the overloads, and if only one
9084 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9086 static int
9088 tree targs,
9089 tree parm,
9090 tree arg,
9091 unification_kind_t strict,
9093 {
9099 {
9102 }
9103 else
9107 /* Handle `&x' where `x' is some static or non-static member
9108 function name. */
9114 /* Strip baselink information. */
9119 {
9120 /* If we got some explicit template args, we need to plug them into
9121 the affected templates before we try to unify, in case the
9122 explicit args will completely resolve the templates in question. */
9128 {
9136 expl_subargs);
9138 {
9142 }
9143 }
9144 }
9147 {
9152 }
9153 else
9156 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9157 to function or pointer to member function argument if the set of
9158 overloaded functions does not contain function templates and at most
9159 one of a set of overloaded functions provides a unique match.
9161 So if we found multiple possibilities, we return success but don't
9162 deduce anything. */
9165 {
9170 }
9175 }
9177 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9178 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9179 different overloads deduce different arguments for a given parm.
9180 ADDR_P is true if the expression for which deduction is being
9181 performed was of the form "& fn" rather than simply "fn".
9183 Returns 1 on success. */
9185 static int
9187 tree orig_targs,
9188 tree targs,
9189 tree parm,
9190 tree arg,
9191 unification_kind_t strict,
9194 {
9196 tree tempargs;
9199 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9200 to function or pointer to member function argument if the set of
9201 overloaded functions does not contain function templates and at most
9202 one of a set of overloaded functions provides a unique match.
9204 So if this is a template, just return success. */
9216 /* We don't copy orig_targs for this because if we have already deduced
9217 some template args from previous args, unify would complain when we
9218 try to deduce a template parameter for the same argument, even though
9219 there isn't really a conflict. */
9226 /* First make sure we didn't deduce anything that conflicts with
9227 explicitly specified args. */
9229 {
9236 {
9237 /* Since we're unifying against ourselves, we will fill in template
9238 args used in the function parm list with our own template parms.
9239 Discard them. */
9242 }
9245 }
9248 {
9253 }
9256 }
9258 /* Verify that nondeduce template argument agrees with the type
9259 obtained from argument deduction. Return nonzero if the
9260 verification fails.
9262 For example:
9264 struct A { typedef int X; };
9265 template <class T, class U> struct C {};
9266 template <class T> struct C<T, typename T::X> {};
9268 Then with the instantiation `C<A, int>', we can deduce that
9269 `T' is `A' but unify () does not check whether `typename T::X'
9270 is `int'. This function ensure that they agree.
9272 TARGS, PARMS are the same as the arguments of unify.
9273 ARGS contains template arguments from all levels. */
9275 static int
9277 {
9284 }
9286 /* PARM is a template class (perhaps with unbound template
9287 parameters). ARG is a fully instantiated type. If ARG can be
9288 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9289 TARGS are as for unify. */
9291 static tree
9293 {
9294 tree copy_of_targs;
9301 /* We need to make a new template argument vector for the call to
9302 unify. If we used TARGS, we'd clutter it up with the result of
9303 the attempted unification, even if this class didn't work out.
9304 We also don't want to commit ourselves to all the unifications
9305 we've already done, since unification is supposed to be done on
9306 an argument-by-argument basis. In other words, consider the
9307 following pathological case:
9309 template <int I, int J, int K>
9310 struct S {};
9312 template <int I, int J>
9313 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9315 template <int I, int J, int K>
9316 void f(S<I, J, K>, S<I, I, I>);
9318 void g() {
9319 S<0, 0, 0> s0;
9320 S<0, 1, 2> s2;
9322 f(s0, s2);
9323 }
9325 Now, by the time we consider the unification involving `s2', we
9326 already know that we must have `f<0, 0, 0>'. But, even though
9327 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9328 because there are two ways to unify base classes of S<0, 1, 2>
9329 with S<I, I, I>. If we kept the already deduced knowledge, we
9330 would reject the possibility I=1. */
9333 /* If unification failed, we're done. */
9339 }
9341 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9342 have already discovered to be satisfactory. ARG_BINFO is the binfo
9343 for the base class of ARG that we are currently examining. */
9345 static tree
9347 tree targs,
9348 tree parm,
9349 tree arg_binfo,
9350 tree rval,
9352 {
9353 tree binfos;
9358 {
9362 /* If there is more than one satisfactory baseclass, then:
9364 [temp.deduct.call]
9366 If they yield more than one possible deduced A, the type
9367 deduction fails.
9369 applies. */
9374 }
9379 /* Process base types. */
9381 {
9385 /* Skip this base, if we've already seen it. */
9389 this_virtual =
9392 /* When searching for a non-virtual, we cannot mark virtually
9393 found binfos. */
9398 parm,
9399 base_binfo,
9400 rval,
9403 /* If we discovered more than one matching base class, we can
9404 stop now. */
9407 }
9410 }
9412 /* Given a template type PARM and a class type ARG, find the unique
9413 base type in ARG that is an instance of PARM. We do not examine
9414 ARG itself; only its base-classes. If there is no appropriate base
9415 class, return NULL_TREE. If there is more than one, return
9416 error_mark_node. PARM may be the type of a partial specialization,
9417 as well as a plain template type. Used by unify. */
9419 static tree
9421 {
9422 tree rval;
9423 tree arg_binfo;
9430 NULL_TREE,
9431 GTB_IGNORE_TYPE);
9433 /* Since get_template_base_recursive marks the bases classes, we
9434 must unmark them here. */
9438 }
9440 /* Returns the level of DECL, which declares a template parameter. */
9442 static int
9444 {
9446 {
9457 }
9458 }
9460 /* Decide whether ARG can be unified with PARM, considering only the
9461 cv-qualifiers of each type, given STRICT as documented for unify.
9462 Returns nonzero iff the unification is OK on that basis.*/
9464 static int
9466 {
9471 {
9472 /* If the cvr quals of parm will not unify with ARG, they'll be
9473 ignored in instantiation, so we have to do the same here. */
9479 }
9490 }
9492 /* Takes parameters as for type_unification. Returns 0 if the
9493 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9494 bitwise or of the following flags:
9496 UNIFY_ALLOW_NONE:
9497 Require an exact match between PARM and ARG.
9498 UNIFY_ALLOW_MORE_CV_QUAL:
9499 Allow the deduced ARG to be more cv-qualified (by qualification
9500 conversion) than ARG.
9501 UNIFY_ALLOW_LESS_CV_QUAL:
9502 Allow the deduced ARG to be less cv-qualified than ARG.
9503 UNIFY_ALLOW_DERIVED:
9504 Allow the deduced ARG to be a template base class of ARG,
9505 or a pointer to a template base class of the type pointed to by
9506 ARG.
9507 UNIFY_ALLOW_INTEGER:
9508 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9509 case for more information.
9510 UNIFY_ALLOW_OUTER_LEVEL:
9511 This is the outermost level of a deduction. Used to determine validity
9512 of qualification conversions. A valid qualification conversion must
9513 have const qualified pointers leading up to the inner type which
9514 requires additional CV quals, except at the outer level, where const
9515 is not required [conv.qual]. It would be normal to set this flag in
9516 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9517 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9518 This is the outermost level of a deduction, and PARM can be more CV
9519 qualified at this point.
9520 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9521 This is the outermost level of a deduction, and PARM can be less CV
9522 qualified at this point.
9523 UNIFY_ALLOW_MAX_CORRECTION:
9524 This is an INTEGER_TYPE's maximum value. Used if the range may
9525 have been derived from a size specification, such as an array size.
9526 If the size was given by a nontype template parameter N, the maximum
9527 value will have the form N-1. The flag says that we can (and indeed
9528 must) unify N with (ARG + 1), an exception to the normal rules on
9529 folding PARM. */
9531 static int
9533 {
9535 tree targ;
9536 tree tparm;
9539 /* I don't think this will do the right thing with respect to types.
9540 But the only case I've seen it in so far has been array bounds, where
9541 signedness is the only information lost, and I think that will be
9542 okay. */
9549 /* We can't deduce anything from this, but we might get all the
9550 template args from other function args. */
9553 /* If PARM uses template parameters, then we can't bail out here,
9554 even if ARG == PARM, since we won't record unifications for the
9555 template parameters. We might need them if we're trying to
9556 figure out which of two things is more specialized. */
9560 /* Immediately reject some pairs that won't unify because of
9561 cv-qualification mismatches. */
9564 /* It is the elements of the array which hold the cv quals of an array
9565 type, and the elements might be template type parms. We'll check
9566 when we recurse. */
9568 /* We check the cv-qualifiers when unifying with template type
9569 parameters below. We want to allow ARG `const T' to unify with
9570 PARM `T' for example, when computing which of two templates
9571 is more specialized, for example. */
9586 {
9590 /* In a type which contains a nested-name-specifier, template
9591 argument values cannot be deduced for template parameters used
9592 within the nested-name-specifier. */
9602 /* The PARM is not one we're trying to unify. Just check
9603 to see if it matches ARG. */
9610 /* Check for mixed types and values. */
9618 {
9619 /* ARG must be constructed from a template class or a template
9620 template parameter. */
9625 {
9629 tree argtmplvec
9633 /* The parameter and argument roles have to be switched here
9634 in order to handle default arguments properly. For example,
9635 template<template <class> class TT> void f(TT<int>)
9636 should be able to accept vector<int> which comes from
9637 template <class T, class Allocator = allocator>
9638 class vector. */
9644 /* Deduce arguments T, i from TT<T> or TT<i>.
9645 We check each element of PARMVEC and ARGVEC individually
9646 rather than the whole TREE_VEC since they can have
9647 different number of elements. */
9650 {
9655 UNIFY_ALLOW_NONE))
9657 }
9658 }
9661 /* Fall through to deduce template name. */
9662 }
9666 {
9667 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9669 /* Simple cases: Value already set, does match or doesn't. */
9674 }
9675 else
9676 {
9677 /* If PARM is `const T' and ARG is only `int', we don't have
9678 a match unless we are allowing additional qualification.
9679 If ARG is `const int' and PARM is just `T' that's OK;
9680 that binds `const int' to `T'. */
9685 /* Consider the case where ARG is `const volatile int' and
9686 PARM is `const T'. Then, T should be `volatile int'. */
9687 arg = cp_build_qualified_type_real
9692 /* Simple cases: Value already set, does match or doesn't. */
9698 /* Make sure that ARG is not a variable-sized array. (Note
9699 that were talking about variable-sized arrays (like
9700 `int[n]'), rather than arrays of unknown size (like
9701 `int[]').) We'll get very confused by such a type since
9702 the bound of the array will not be computable in an
9703 instantiation. Besides, such types are not allowed in
9704 ISO C++, so we can do as we please here. */
9707 }
9717 /* The PARM is not one we're trying to unify. Just check
9718 to see if it matches ARG. */
9728 /* [temp.deduct.type] If, in the declaration of a function template
9729 with a non-type template-parameter, the non-type
9730 template-parameter is used in an expression in the function
9731 parameter-list and, if the corresponding template-argument is
9732 deduced, the template-argument type shall match the type of the
9733 template-parameter exactly, except that a template-argument
9734 deduced from an array bound may be of any integral type.
9735 The non-type parameter might use already deduced type parameters. */
9738 /* Template-parameter dependent expression. Just accept it for now.
9739 It will later be processed in convert_template_argument. */
9740 ;
9748 /* We haven't deduced the type of this parameter yet. Try again
9749 later. */
9751 else
9758 {
9759 /* A pointer-to-member constant can be unified only with
9760 another constant. */
9764 /* Just unify the class member. It would be useless (and possibly
9765 wrong, depending on the strict flags) to unify also
9766 PTRMEM_CST_CLASS, because we want to be sure that both parm and
9767 arg refer to the same variable, even if through different
9768 classes. For instance:
9770 struct A { int x; };
9771 struct B : A { };
9773 Unification of &A::x and &B::x must succeed. */
9776 }
9779 {
9783 /* [temp.deduct.call]
9785 A can be another pointer or pointer to member type that can
9786 be converted to the deduced A via a qualification
9787 conversion (_conv.qual_).
9789 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9790 This will allow for additional cv-qualification of the
9791 pointed-to types if appropriate. */
9794 /* The derived-to-base conversion only persists through one
9795 level of pointers. */
9800 }
9832 {
9842 }
9843 /* We have already checked cv-qualification at the top of the
9844 function. */
9848 /* As far as unification is concerned, this wins. Later checks
9849 will invalidate it if necessary. */
9852 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9853 /* Type INTEGER_CST can come from ordinary constant template args. */
9863 {
9872 UNIFY_ALLOW_NONE))
9875 }
9883 {
9890 strict);
9891 }
9894 {
9898 {
9899 /* First, we try to unify the PARM and ARG directly. */
9904 {
9905 /* Fallback to the special case allowed in
9906 [temp.deduct.call]:
9908 If P is a class, and P has the form
9909 template-id, then A can be a derived class of
9910 the deduced A. Likewise, if P is a pointer to
9911 a class of the form template-id, A can be a
9912 pointer to a derived class pointed to by the
9913 deduced A. */
9919 }
9920 }
9924 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9925 Then, we should unify `int' and `U'. */
9927 else
9928 /* There's no chance of unification succeeding. */
9933 }
9957 strict);
9968 /* Matched cases are handled by the ARG == PARM test above. */
9974 {
9975 /* We handle this case specially, since it comes up with
9976 arrays. In particular, something like:
9978 template <int N> void f(int (&x)[N]);
9980 Here, we are trying to unify the range type, which
9981 looks like [0 ... (N - 1)]. */
9989 }
9990 /* Else fall through. */
9994 {
9996 /* We're looking at an expression. This can happen with
9997 something like:
9999 template <int I>
10000 void foo(S<I>, S<I + 2>);
10002 This is a "nondeduced context":
10004 [deduct.type]
10006 The nondeduced contexts are:
10008 --A type that is a template-id in which one or more of
10009 the template-arguments is an expression that references
10010 a template-parameter.
10012 In these cases, we assume deduction succeeded, but don't
10013 actually infer any unifications. */
10018 else
10020 }
10021 else
10026 }
10027 }
10028 \f
10029 /* Called if RESULT is explicitly instantiated, or is a member of an
10030 explicitly instantiated class, or if using -frepo and the
10031 instantiation of RESULT has been assigned to this file. */
10033 void
10035 {
10036 /* We used to set this unconditionally; we moved that to
10037 do_decl_instantiation so it wouldn't get set on members of
10038 explicit class template instantiations. But we still need to set
10039 it here for the 'extern template' case in order to suppress
10040 implicit instantiations. */
10044 /* If this entity has already been written out, it's too late to
10045 make any modifications. */
10050 /* The TREE_PUBLIC flag for function declarations will have been
10051 set correctly by tsubst. */
10054 /* This might have been set by an earlier implicit instantiation. */
10058 {
10062 /* Always make artificials weak. */
10065 /* For WIN32 we also want to put explicit instantiations in
10066 linkonce sections. */
10069 }
10073 }
10075 /* Given two function templates PAT1 and PAT2, return:
10077 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
10079 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10080 -1 if PAT2 is more specialized than PAT1.
10081 0 if neither is more specialized.
10083 LEN is passed through to fn_type_unification. */
10085 int
10087 {
10088 tree targs;
10091 /* If template argument deduction succeeds, we substitute the
10092 resulting arguments into non-deduced contexts. While doing that,
10093 we must be aware that we may encounter dependent types. */
10107 }
10109 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10111 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10112 -1 if PAT2 is more specialized than PAT1.
10113 0 if neither is more specialized.
10115 FULL_ARGS is the full set of template arguments that triggers this
10116 partial ordering. */
10118 int
10120 {
10121 tree targs;
10135 }
10137 /* Return the template arguments that will produce the function signature
10138 DECL from the function template FN, with the explicit template
10139 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
10140 also match. Return NULL_TREE if no satisfactory arguments could be
10141 found. DEDUCE and LEN are passed through to fn_type_unification. */
10143 static tree
10145 tree decl,
10146 tree explicit_args,
10150 {
10153 tree decl_type;
10154 tree decl_arg_types;
10157 /* Substitute the explicit template arguments into the type of DECL.
10158 The call to fn_type_unification will handle substitution into the
10159 FN. */
10162 {
10163 tree tmpl;
10164 tree converted_args;
10168 else
10169 /* We can get here for some invalid specializations. */
10172 converted_args
10182 }
10185 /* Never do unification on the 'this' parameter. */
10190 decl_arg_types,
10199 }
10201 /* For most uses, we want to check the return type. */
10203 static tree
10205 {
10207 }
10209 /* But for resolve_overloaded_unification, we only care about the parameter
10210 types. */
10212 static tree
10214 {
10216 }
10218 /* Return the innermost template arguments that, when applied to a
10219 template specialization whose innermost template parameters are
10220 TPARMS, and whose specialization arguments are PARMS, yield the
10221 ARGS.
10223 For example, suppose we have:
10225 template <class T, class U> struct S {};
10226 template <class T> struct S<T*, int> {};
10228 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10229 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10230 int}. The resulting vector will be {double}, indicating that `T'
10231 is bound to `double'. */
10233 static tree
10235 {
10240 UNIFY_ALLOW_NONE))
10251 }
10253 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10254 Pick the most specialized template, and return the corresponding
10255 instantiation, or if there is no corresponding instantiation, the
10256 template itself. If there is no most specialized template,
10257 error_mark_node is returned. If there are no templates at all,
10258 NULL_TREE is returned. */
10260 tree
10262 {
10271 {
10275 ;
10276 else
10277 {
10279 {
10283 }
10285 }
10286 }
10289 {
10294 }
10297 }
10299 /* Return the most specialized of the list of templates in FNS that can
10300 produce an instantiation matching DECL, given the explicit template
10301 arguments EXPLICIT_ARGS. */
10303 static tree
10305 {
10310 {
10316 }
10319 }
10321 /* If DECL is a specialization of some template, return the most
10322 general such template. Otherwise, returns NULL_TREE.
10324 For example, given:
10326 template <class T> struct S { template <class U> void f(U); };
10328 if TMPL is `template <class U> void S<int>::f(U)' this will return
10329 the full template. This function will not trace past partial
10330 specializations, however. For example, given in addition:
10332 template <class T> struct S<T*> { template <class U> void f(U); };
10334 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10335 `template <class T> template <class U> S<T*>::f(U)'. */
10337 tree
10339 {
10340 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10341 an immediate specialization. */
10343 {
10347 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10348 template friend. */
10353 }
10355 /* Look for more and more general templates. */
10357 {
10358 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10359 (See cp-tree.h for details.) */
10367 /* Stop if we run into an explicitly specialized class template. */
10374 }
10377 }
10379 /* Return the most specialized of the class template specializations
10380 of TMPL which can produce an instantiation matching ARGS, or
10381 error_mark_node if the choice is ambiguous. */
10383 static tree
10385 {
10387 tree t;
10388 tree champ;
10393 {
10394 tree spec_args
10397 {
10400 }
10401 }
10410 {
10413 ;
10414 else
10415 {
10417 {
10421 }
10423 }
10424 }
10427 {
10431 }
10434 }
10436 /* Explicitly instantiate DECL. */
10438 void
10440 {
10445 /* An error occurred, for which grokdeclarator has already issued
10446 an appropriate message. */
10449 {
10452 }
10454 {
10455 /* There is an asymmetry here in the way VAR_DECLs and
10456 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10457 the latter, the DECL we get back will be marked as a
10458 template instantiation, and the appropriate
10459 DECL_TEMPLATE_INFO will be set up. This does not happen for
10460 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10461 should handle VAR_DECLs as it currently handles
10462 FUNCTION_DECLs. */
10465 {
10468 }
10469 }
10471 {
10474 }
10475 else
10478 /* Check for various error cases. Note that if the explicit
10479 instantiation is valid the RESULT will currently be marked as an
10480 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10481 until we get here. */
10484 {
10485 /* DR 259 [temp.spec].
10487 Both an explicit instantiation and a declaration of an explicit
10488 specialization shall not appear in a program unless the explicit
10489 instantiation follows a declaration of the explicit specialization.
10491 For a given set of template parameters, if an explicit
10492 instantiation of a template appears after a declaration of an
10493 explicit specialization for that template, the explicit
10494 instantiation has no effect. */
10496 }
10498 {
10499 /* [temp.spec]
10501 No program shall explicitly instantiate any template more
10502 than once.
10504 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10505 instantiation was `extern' and the second is not, and EXTERN_P for
10506 the opposite case. If -frepo, chances are we already got marked
10507 as an explicit instantiation because of the repo file. */
10511 /* If we've already instantiated the template, just return now. */
10514 }
10516 {
10519 }
10521 {
10524 }
10527 ;
10529 {
10533 }
10534 else
10536 storage);
10543 }
10545 void
10547 {
10553 {
10556 }
10557 }
10559 /* Called from do_type_instantiation through binding_table_foreach to
10560 do recursive instantiation for the type bound in ENTRY. */
10561 static void
10563 {
10569 }
10571 /* Perform an explicit instantiation of template class T. STORAGE, if
10572 non-null, is the RID for extern, inline or static. COMPLAIN is
10573 nonzero if this is called from the parser, zero if called recursively,
10574 since the standard is unclear (as detailed below). */
10576 void
10578 {
10587 {
10590 }
10595 {
10598 t);
10600 }
10603 {
10614 else
10615 {
10617 storage);
10619 }
10620 }
10623 {
10624 /* DR 259 [temp.spec].
10626 Both an explicit instantiation and a declaration of an explicit
10627 specialization shall not appear in a program unless the explicit
10628 instantiation follows a declaration of the explicit specialization.
10630 For a given set of template parameters, if an explicit
10631 instantiation of a template appears after a declaration of an
10632 explicit specialization for that template, the explicit
10633 instantiation has no effect. */
10635 }
10637 {
10638 /* [temp.spec]
10640 No program shall explicitly instantiate any template more
10641 than once.
10643 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10644 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10645 are we already got marked as an explicit instantiation because of the
10646 repo file. All these cases are OK. */
10651 /* If we've already instantiated the template, just return now. */
10654 }
10662 {
10663 tree tmp;
10665 /* In contrast to implicit instantiation, where only the
10666 declarations, and not the definitions, of members are
10667 instantiated, we have here:
10669 [temp.explicit]
10671 The explicit instantiation of a class template specialization
10672 implies the instantiation of all of its members not
10673 previously explicitly specialized in the translation unit
10674 containing the explicit instantiation.
10676 Of course, we can't instantiate member template classes, since
10677 we don't have any arguments for them. Note that the standard
10678 is unclear on whether the instantiation of the members are
10679 *explicit* instantiations or not. We choose to be generous,
10680 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10681 the explicit instantiation of a class where some of the members
10682 have no definition in the current translation unit. */
10688 {
10693 }
10697 {
10702 }
10707 }
10708 }
10710 /* Given a function DECL, which is a specialization of TMPL, modify
10711 DECL to be a re-instantiation of TMPL with the same template
10712 arguments. TMPL should be the template into which tsubst'ing
10713 should occur for DECL, not the most general template.
10715 One reason for doing this is a scenario like this:
10717 template <class T>
10718 void f(const T&, int i);
10720 void g() { f(3, 7); }
10722 template <class T>
10723 void f(const T& t, const int i) { }
10725 Note that when the template is first instantiated, with
10726 instantiate_template, the resulting DECL will have no name for the
10727 first parameter, and the wrong type for the second. So, when we go
10728 to instantiate the DECL, we regenerate it. */
10730 static void
10732 {
10733 /* The most general version of TMPL. */
10734 tree gen_tmpl;
10735 /* The arguments used to instantiate DECL, from the most general
10736 template. */
10737 tree args;
10738 tree code_pattern;
10739 tree new_decl;
10745 /* Unregister the specialization so that when we tsubst we will not
10746 just return DECL. We don't have to unregister DECL from TMPL
10747 because if would only be registered there if it were a partial
10748 instantiation of a specialization, which it isn't: it's a full
10749 instantiation. */
10754 /* If the DECL was not unregistered then something peculiar is
10755 happening: we created a specialization but did not call
10756 register_specialization for it. */
10759 /* Make sure that we can see identifiers, and compute access
10760 correctly. */
10763 /* Do the substitution to get the new declaration. */
10767 {
10768 /* Set up DECL_INITIAL, since tsubst doesn't. */
10773 }
10775 {
10776 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10777 new decl. */
10779 /* And don't complain about a duplicate definition. */
10781 }
10785 /* The immediate parent of the new template is still whatever it was
10786 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10787 general template. We also reset the DECL_ASSEMBLER_NAME since
10788 tsubst always calculates the name as if the function in question
10789 were really a template instance, and sometimes, with friend
10790 functions, this is not so. See tsubst_friend_function for
10791 details. */
10797 /* Call duplicate decls to merge the old and new declarations. */
10800 /* Now, re-register the specialization. */
10802 }
10804 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10805 substituted to get DECL. */
10807 tree
10809 {
10812 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10813 for the instantiation. This is not always the most general
10814 template. Consider, for example:
10816 template <class T>
10817 struct S { template <class U> void f();
10818 template <> void f<int>(); };
10820 and an instantiation of S<double>::f<int>. We want TD to be the
10821 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10823 more general template. */
10825 /* We must also deal with friend templates. Given:
10827 template <class T> struct S {
10828 template <class U> friend void f() {};
10829 };
10831 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10832 so far as the language is concerned, but that's still
10833 where we get the pattern for the instantiation from. On
10834 other hand, if the definition comes outside the class, say:
10836 template <class T> struct S {
10837 template <class U> friend void f();
10838 };
10839 template <class U> friend void f() {}
10841 we don't need to look any further. That's what the check for
10842 DECL_INITIAL is for. */
10846 {
10847 /* The present template, TD, should not be a definition. If it
10848 were a definition, we should be using it! Note that we
10849 cannot restructure the loop to just keep going until we find
10850 a template with a definition, since that might go too far if
10851 a specialization was declared, but not defined. */
10856 /* Fetch the more general template. */
10858 }
10861 }
10863 /* Produce the definition of D, a _DECL generated from a template. If
10864 DEFER_OK is nonzero, then we don't have to actually do the
10865 instantiation now; we just have to do it sometime. */
10867 tree
10869 {
10871 tree gen_args;
10872 tree args;
10873 tree td;
10874 tree code_pattern;
10875 tree spec;
10876 tree gen_tmpl;
10881 /* This function should only be used to instantiate templates for
10882 functions and static member variables. */
10886 /* Variables are never deferred; if instantiation is required, they
10887 are instantiated right away. That allows for better code in the
10888 case that an expression refers to the value of the variable --
10889 if the variable has a constant value the referring expression can
10890 take advantage of that fact. */
10894 /* Don't instantiate cloned functions. Instead, instantiate the
10895 functions they cloned. */
10900 /* D has already been instantiated. It might seem reasonable to
10901 check whether or not D is an explicit instantiation, and, if so,
10902 stop here. But when an explicit instantiation is deferred
10903 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10904 is set, even though we still need to do the instantiation. */
10907 /* If we already have a specialization of this declaration, then
10908 there's no reason to instantiate it. Note that
10909 retrieve_specialization gives us both instantiations and
10910 specializations, so we must explicitly check
10911 DECL_TEMPLATE_SPECIALIZATION. */
10918 /* This needs to happen before any tsubsting. */
10924 /* We may be in the middle of deferred access check. Disable it now. */
10927 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10928 for the instantiation. */
10934 /* In the case of a friend template whose definition is provided
10935 outside the class, we may have too many arguments. Drop the
10936 ones we don't need. The same is true for specializations. */
10937 args = get_innermost_template_args
10939 else
10944 else
10950 {
10951 /* Let the repository code that this template definition is
10952 available.
10954 The repository doesn't need to know about cloned functions
10955 because they never actually show up in the object file. It
10956 does need to know about the clones; those are the symbols
10957 that the linker will be emitting error messages about. */
10960 {
10961 tree t;
10967 }
10968 else
10973 }
10976 {
10977 /* Recheck the substitutions to obtain any warning messages
10978 about ignoring cv qualifiers. */
10982 /* Make sure that we can see identifiers, and compute access
10983 correctly. D is already the target FUNCTION_DECL with the
10984 right context. */
10988 {
10992 /* Don't simply tsubst the function type, as that will give
10993 duplicate warnings about poor parameter qualifications.
10994 The function arguments are the same as the decl_arguments
10995 without the top level cv qualifiers. */
10997 }
11001 }
11005 /* We should have set up DECL_INITIAL in instantiate_class_template. */
11007 /* Reject all external templates except inline functions. */
11013 /* Defer all other templates, unless we have been explicitly
11014 forbidden from doing so. We restore the source position here
11015 because it's used by add_pending_template. */
11017 {
11022 /* [temp.explicit]
11024 The definition of a non-exported function template, a
11025 non-exported member function template, or a non-exported
11026 member function or static data member of a class template
11027 shall be present in every translation unit in which it is
11028 explicitly instantiated. */
11029 pedwarn
11034 }
11040 /* Mark D as instantiated so that recursive calls to
11041 instantiate_decl do not try to instantiate it again. */
11044 /* Regenerate the declaration in case the template has been modified
11045 by a subsequent redeclaration. */
11048 /* We already set the file and line above. Reset them now in case
11049 they changed as a result of calling
11050 regenerate_decl_from_template. */
11054 {
11055 /* Clear out DECL_RTL; whatever was there before may not be right
11056 since we've reset the type of the declaration. */
11064 {
11065 /* The fact that this code is executing indicates that:
11067 (1) D is a template static data member, for which a
11068 definition is available.
11070 (2) An implicit or explicit instantiation has occurred.
11072 (3) We are not going to emit a definition of the static
11073 data member at this time.
11075 This situation is peculiar, but it occurs on platforms
11076 without weak symbols when performing an implicit
11077 instantiation. There, we cannot implicitly instantiate a
11078 defined static data member in more than one translation
11079 unit, so import_export_decl marks the declaration as
11080 external; we must rely on explicit instantiation.
11082 Reset instantiated marker to make sure that later
11083 explicit instantiation will be processed. */
11085 }
11086 else
11087 {
11088 /* This is done in analogous to `start_decl'. It is
11089 required for correct access checking. */
11095 /* Normally, pop_nested_class is called by cp_finish_decl
11096 above. But when instantiate_decl is triggered during
11097 instantiate_class_template processing, its DECL_CONTEXT
11098 is still not completed yet, and pop_nested_class isn't
11099 called. */
11102 }
11103 }
11105 {
11106 htab_t saved_local_specializations;
11107 tree subst_decl;
11108 tree tmpl_parm;
11109 tree spec_parm;
11111 /* Mark D as instantiated so that recursive calls to
11112 instantiate_decl do not try to instantiate it again. */
11115 /* Save away the current list, in case we are instantiating one
11116 template from within the body of another. */
11119 /* Set up the list of local specializations. */
11121 hash_local_specialization,
11122 eq_local_specializations,
11123 NULL);
11125 /* Set up context. */
11129 /* Create substitution entries for the parameters. */
11134 {
11138 }
11140 {
11144 }
11147 /* Substitute into the body of the function. */
11151 /* We don't need the local specializations any more. */
11155 /* Finish the function. */
11158 }
11160 /* We're not deferring instantiation any more. */
11166 out:
11174 }
11176 /* Run through the list of templates that we wish we could
11177 instantiate, and instantiate any we can. */
11179 int
11181 {
11188 do
11189 {
11194 {
11200 {
11201 tree fn;
11204 {
11208 fn;
11213 {
11216 }
11217 }
11220 /* If INSTANTIATION has been instantiated, then we don't
11221 need to consider it again in the future. */
11223 else
11224 {
11227 }
11228 }
11229 else
11230 {
11233 {
11237 {
11240 }
11241 }
11245 /* If INSTANTIATION has been instantiated, then we don't
11246 need to consider it again in the future. */
11248 else
11249 {
11252 }
11253 }
11256 }
11258 }
11263 }
11265 /* Substitute ARGVEC into T, which is a list of initializers for
11266 either base class or a non-static data member. The TREE_PURPOSEs
11267 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11268 instantiate_decl. */
11270 static tree
11272 {
11276 {
11277 tree decl;
11278 tree init;
11279 tree val;
11282 NULL_TREE);
11288 NULL_TREE);
11290 ;
11300 {
11304 }
11305 }
11307 }
11309 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11311 static void
11313 {
11318 else
11320 }
11322 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11323 is the instantiation (which should have been created with
11324 start_enum) and ARGS are the template arguments to use. */
11326 static void
11328 {
11329 tree e;
11332 {
11333 tree value;
11334 tree decl;
11337 /* Note that in a template enum, the TREE_VALUE is the
11338 CONST_DECL, not the corresponding INTEGER_CST. */
11341 NULL_TREE);
11343 /* Give this enumeration constant the correct access. */
11346 /* Actually build the enumerator itself. */
11348 }
11353 }
11355 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11356 its type -- but without substituting the innermost set of template
11357 arguments. So, innermost set of template parameters will appear in
11358 the type. */
11360 tree
11362 {
11363 tree fn_type;
11364 tree tmpl;
11365 tree targs;
11366 tree tparms;
11374 /* There should be as many levels of arguments as there are levels
11375 of parameters. */
11381 /* No substitution is necessary. */
11382 ;
11383 else
11384 {
11386 tree partial_args;
11388 /* Replace the innermost level of the TARGS with NULL_TREEs to
11389 let tsubst know not to substitute for those parameters. */
11398 /* Make sure that we can see identifiers, and compute access
11399 correctly. We can just use the context of DECL for the
11400 partial substitution here. It depends only on outer template
11401 parameters, regardless of whether the innermost level is
11402 specialized or not. */
11406 /* Now, do the (partial) substitution to figure out the
11407 appropriate function type. */
11411 /* Substitute into the template parameters to obtain the real
11412 innermost set of parameters. This step is important if the
11413 innermost set of template parameters contains value
11414 parameters whose types depend on outer template parameters. */
11419 }
11422 }
11424 /* Return truthvalue if we're processing a template different from
11425 the last one involved in diagnostics. */
11426 int
11428 {
11430 }
11432 /* Remember current template involved in diagnostics. */
11433 void
11435 {
11437 }
11439 tree
11441 {
11443 }
11445 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11446 type. Return zero for ok, nonzero for disallowed. Issue error and
11447 warning messages under control of COMPLAIN. */
11449 static int
11451 {
11465 type);
11467 }
11469 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11470 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11472 static bool
11474 {
11475 tree scope;
11477 /* [temp.dep.type]
11479 A type is dependent if it is:
11481 -- a template parameter. */
11484 /* -- a qualified-id with a nested-name-specifier which contains a
11485 class-name that names a dependent type or whose unqualified-id
11486 names a dependent type. */
11489 /* -- a cv-qualified type where the cv-unqualified type is
11490 dependent. */
11492 /* -- a compound type constructed from any dependent type. */
11502 {
11503 tree arg_type;
11508 arg_type;
11513 }
11514 /* -- an array type constructed from any dependent type or whose
11515 size is specified by a constant expression that is
11516 value-dependent. */
11518 {
11520 && ((value_dependent_expression_p
11522 || (type_dependent_expression_p
11526 }
11528 /* -- a template-id in which either the template name is a template
11529 parameter ... */
11532 /* ... or any of the template arguments is a dependent type or
11533 an expression that is type-dependent or value-dependent. */
11535 && (any_dependent_template_arguments_p
11539 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11540 expression is not type-dependent, then it should already been
11541 have resolved. */
11545 /* The standard does not specifically mention types that are local
11546 to template functions or local classes, but they should be
11547 considered dependent too. For example:
11549 template <int I> void f() {
11550 enum E { a = I };
11551 S<sizeof (E)> s;
11552 }
11554 The size of `E' cannot be known until the value of `I' has been
11555 determined. Therefore, `E' must be considered dependent. */
11562 /* Other types are non-dependent. */
11564 }
11566 /* Returns TRUE if TYPE is dependent, in the sense of
11567 [temp.dep.type]. */
11569 bool
11571 {
11572 /* If there are no template parameters in scope, then there can't be
11573 any dependent types. */
11577 /* If the type is NULL, we have not computed a type for the entity
11578 in question; in that case, the type is dependent. */
11582 /* Erroneous types can be considered non-dependent. */
11586 /* If we have not already computed the appropriate value for TYPE,
11587 do so now. */
11589 {
11592 }
11595 }
11597 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11599 static bool
11601 {
11602 tree scope;
11603 tree name;
11613 /* [temp.dep.expr]
11615 An id-expression is type-dependent if it contains a
11616 nested-name-specifier that contains a class-name that names a
11617 dependent type. */
11618 /* The suggested resolution to Core Issue 2 implies that if the
11619 qualifying type is the current class, then we must peek
11620 inside it. */
11629 }
11631 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11632 [temp.dep.constexpr] */
11634 bool
11636 {
11640 /* A name declared with a dependent type. */
11645 /* A non-type template parameter. */
11650 /* A constant with integral or enumeration type and is initialized
11651 with an expression that is value-dependent. */
11657 /* These expressions are value-dependent if the type to which the
11658 cast occurs is dependent or the expression being casted is
11659 value-dependent. */
11665 {
11668 /* A functional cast has a list of operands. */
11671 {
11672 do
11673 {
11677 }
11680 }
11681 else
11683 }
11684 /* A `sizeof' expression is value-dependent if the operand is
11685 type-dependent. */
11688 {
11693 }
11699 /* A constant expression is value-dependent if any subexpression is
11700 value-dependent. */
11702 {
11704 {
11712 || (value_dependent_expression_p
11715 {
11718 /* In some cases, some of the operands may be missing.
11719 (For example, in the case of PREDECREMENT_EXPR, the
11720 amount to increment by may be missing.) That doesn't
11721 make the expression dependent. */
11723 && (value_dependent_expression_p
11727 }
11728 }
11729 }
11731 /* The expression is not value-dependent. */
11733 }
11735 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11736 [temp.dep.expr]. */
11738 bool
11740 {
11747 /* An unresolved name is always dependent. */
11751 /* Some expression forms are never type-dependent. */
11761 /* The types of these expressions depends only on the type to which
11762 the cast occurs. */
11770 /* The types of these expressions depends only on the type created
11771 by the expression. */
11774 {
11775 /* For NEW_EXPR tree nodes created inside a template, either
11776 the object type itself or a TREE_LIST may appear as the
11777 operand 1. */
11780 /* This is an array type. We need to check array dimensions
11781 as well. */
11783 || value_dependent_expression_p
11785 else
11787 }
11791 type_dependent_expression_p))
11797 && (any_dependent_template_arguments_p
11806 {
11811 {
11817 }
11822 {
11827 }
11829 {
11831 {
11835 }
11837 }
11839 }
11842 }
11844 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11845 contains a type-dependent expression. */
11847 bool
11849 {
11851 {
11857 }
11859 }
11861 /* Returns TRUE if the ARG (a template argument) is dependent. */
11863 static bool
11865 {
11874 else
11877 }
11879 /* Returns true if ARGS (a collection of template arguments) contains
11880 any dependent arguments. */
11882 bool
11884 {
11892 {
11897 }
11900 }
11902 /* Returns TRUE if the template TMPL is dependent. */
11904 bool
11906 {
11908 {
11910 {
11914 }
11916 }
11918 /* Template template parameters are dependent. */
11922 /* So are qualified names that have not been looked up. */
11925 /* So are member templates of dependent classes. */
11929 }
11931 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11933 bool
11935 {
11938 }
11940 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11941 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11942 can be found. Note that this function peers inside uninstantiated
11943 templates and therefore should be used only in extremely limited
11944 situations. */
11946 tree
11948 {
11949 tree scope;
11950 tree name;
11951 tree decl;
11960 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11961 it first before we can figure out what NAME refers to. */
11964 /* If we don't know what SCOPE refers to, then we cannot resolve the
11965 TYPENAME_TYPE. */
11968 /* If the SCOPE is a template type parameter, we have no way of
11969 resolving the name. */
11972 /* If the SCOPE is not the current instantiation, there's no reason
11973 to look inside it. */
11976 /* If SCOPE is a partial instantiation, it will not have a valid
11977 TYPE_FIELDS list, so use the original template. */
11979 /* Enter the SCOPE so that name lookup will be resolved as if we
11980 were in the class definition. In particular, SCOPE will no
11981 longer be considered a dependent type. */
11983 /* Look up the declaration. */
11985 /* Obtain the set of qualifiers applied to the TYPE. */
11987 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11988 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11996 {
11997 tree tmpl;
11998 tree args;
11999 /* Obtain the template and the arguments. */
12002 /* Instantiate the template. */
12005 }
12006 else
12008 /* Qualify the resulting type. */
12011 /* Leave the SCOPE. */
12015 }
12017 /* EXPR is an expression which is not type-dependent. Return a proxy
12018 for EXPR that can be used to compute the types of larger
12019 expressions containing EXPR. */
12021 tree
12023 {
12024 /* Preserve null pointer constants so that the type of things like
12025 "p == 0" where "p" is a pointer can be determined. */
12028 /* Preserve OVERLOADs; the functions must be available to resolve
12029 types. */
12032 /* Preserve string constants; conversions from string constants to
12033 "char *" are allowed, even though normally a "const char *"
12034 cannot be used to initialize a "char *". */
12037 /* Preserve arithmetic constants, as an optimization -- there is no
12038 reason to create a new node. */
12057 /* Otherwise, build a NON_DEPENDENT_EXPR.
12059 REFERENCE_TYPEs are not stripped for expressions in templates
12060 because doing so would play havoc with mangling. Consider, for
12061 example:
12063 template <typename T> void f<T& g>() { g(); }
12065 In the body of "f", the expression for "g" will have
12066 REFERENCE_TYPE, even though the standard says that it should
12067 not. The reason is that we must preserve the syntactic form of
12068 the expression so that mangling (say) "f<g>" inside the body of
12069 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12070 stripped here. */
12072 }
12074 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12075 Return a new TREE_LIST with the various arguments replaced with
12076 equivalent non-dependent expressions. */
12078 tree
12080 {
12081 tree a;
12082 tree new_args;
12088 new_args);
12090 }